In this study, we determined exercise-induced angiogenesis in mice lacking almost all miRNAs by deleting Dicer, an enzyme essential for microRNA (miRNA) processing and in mice lacking specific miRNAs.
First, the tamoxifen-induced Dicer knockout mice died within 5 weeks after tamoxifen administration, suggesting that miRNAs play an important role in maintaining life.
With regard to analysis using specific miRNA-deficient mice, even in the mice lacking miR-23 cluster miRNAs showed normal exercise-induced angiogenesis in response to endurance exercise training. These findings suggest that the role of miR-23 cluster miRNAs in exercise-induced angiogenesis in skeletal muscle is limited.

Using aging-model mice and young mice together with acute exercise model mice and endurance exercise model mice, grobal mRNA sequence and ribosome profiling were performed using next-generation sequencer. Changed variables and factors based on the analyses were further confirmed by real-time PCR and western blotting, and messages and proteins were quantified. In addition, gene network analyses were performed to capture changes at the system level of skeletal muscle, and found interesting genes and their potentially new functions.

The present study investigated the effect of sleep quality on athletic performance, the mechanism underlying decrease in sleep quality, and the effect of replenishment of the deficient substance on sleep and athletic performance. We demonstrated that the sleep quality affected cognitive performance during a relatively intense aerobic exercise. We found using metabolomics that carnosine and ornithine were decreased by poor sleep quality. Furthermore, the present study suggested that intake of carnosine improved sleep and athletic performance.

We developed an in vivo imaging system to combine spining-disc conforcal system with sensitive CCD camera. As a result of this project, we observed that the Nuclear factor of activated T-cells（NFAT）were translocated into nucleus in response to muscle contraction in adult skeletal muscle.
We will apply this technique to see various phenomena in skeletal muscle in near the future

We investigated the role of microRNA on mechanical stress-induced muscle adaptation by using Dicer1 knock-out mice (Dicer1 KO). As a result, the muscle-specific Dicer1KO mice died by 6 weeks due to dysfunction of muscles, suggesting that microRNAs in muscle play important roles in homeostasis of muscles.

In order to explore new biomarkers which respond to exercise and stress, we performed proteomics using blood and urine samples before and after exhaustive exercise and identified the molecules using mass spectrometric analyses. Among the molecules which exhibited remarkable increases, we developed measurement system using ELISA. Also, we identified several microRNAs in the blood circulation in response to acute resistant exercise using microarray, and quantified expression levels using real-time PCR. Furthermore, we set up global analyses of translation dynamics using ribosome profiling for biomarker discovery.

The purpose of this study was evaluating the availability of salivary HSP70 to assess the physical condition in athletes and elderly individuals. The salivary HSP70 was increased after the acute intensive exercise. In athletes, continuous intensive exercise did not markedly change resting salivary HSP70 levels. This result might be influenced by individual differences of HSP70 responses to intensive exercise. In elderly subjects, continuous moderate exercise training enhanced resting salivary HSP70. In addition, HSP70 might be involved with T-cell activation in response to exercise training. In conclusion, salivary HSP70 might be useful to assess the physical condition in elderly subjects, while it might require to consideration in athletes.

Mechanical strain has been reported to affect the proliferation/differentiation of many cell types. however, the effects of mechanotransduction on embryonic stem (ES) cells remains unknown. To investigate the effects of mechanical strain on ES cell fate, we examined the expression of Nanog as well as Nanog-associated intracellular signaling during uniaxial cyclic stretch. The mouse ES cell was plated onto elastic membranes, and we applied 10% strain at 0.16 Hz. The expression of Nanog was reduced during ES cell differentiation in response to the withdrawal of leukemia inhibitory factor (LIF); however, two days of mechanical strain attenuated this reduction of Nanog expression. On the other hand, the mechanical strain promoted PI3K-Akt signaling, which is reported as an upstream of Nanog transcription.These findings imply that mechanical force plays a role in regulating Nanog expression in ES cells through the actin cytoskeleton-PI3K-Akt signaling.

Sex steroid hormones are mainly produced and secreted by the ovary, testis, and adrenal cortex and affect diverse physiological processes of target organs or tissues, such as reproductive organs, bones, liver, heart, vasculature, brain, and skeletal muscles. Previously, we demonstrated that skeletal muscles are capable of locally synthesizing circulating DHEA to testosterone and estrogen. This study examined association of life-style related diseases and sarcopenia in local skeletal and cardiac muscles and intended to apply it to exercise therapy for anti-aging. Our data demonstrated that local steroidogenesis is involved in age-related life-style related diseases and sarcopenia, suggesting that this mechanism provides beneficial information as a basic finding of the exercise therapy for anti-aging prevention.

The aim of this study is to determine gene regulation related to physical exercise, especially focusing on post-transcriptional control due to mechanical stress-induced microRNA (miRNA)s. We first identified several mechanical stress-induced miRNAs by a comprehensive microarray analysis. Among them, we chose miR-23a to analyze with respect to its function in skeletal muscle by using cultured cells and experimental animals. We found that miR-23a inhibits skeletal muscle atrophy by suppressing the translation of two ubiquitin ligases, atrogin-1 and MuRF1 in their 3'UTR dependent manner.

The purpose of this study was to examine the effects of exercise training on immune function in elderly individuals. Moderate exercise training might up-regulate T-cell activation in elderly. In older rat, moderate exercise training might increase splenic lymphocyte-subsets in relation to T-cell activation. Moreover, combined lactobacillus intake and moderate exercise training might bolster mucosal immune function in elderly subjects. Consequently, exercise training might enhance immune function in elderly people.

本研究は,すでに感染し,身体に潜在しているウィルスDNAを指標として個体全体の免疫機能を定量化し,感染症との関係を明らかにしようとする研究である.本研究では以下の3つの目的を設定している:
1.潜在性ウィルスの再活性化と他の免疫学的指標の関連性の検討
2.健常者を対象にウィルス再活性化と感染症罹患リスクとの関係の検討
3.実際のフィールドでスポーツ選手のウィルス再活性化を指標として感染症罹患リスクをモニタリングし,コンディショニングへの応用の可能性を探る
平成19年度は上記の2と3に関する検討を行った.
健常人を対象としたウィルスDNAの変化と他の免疫学的指標の関連の検討では,ウィルスDNAの変化と唾液中SIgA濃度などの免疫学的指標の関連について相関解析を行い,それらの関連性について検討し,論文を本年度3編発表した.また,投稿準備中の論文が2編ある.
全体統括
平成18-19年度に本研究を行った.全体期間を通じて,英文論文5編,和文論文1編を発表した.また投稿準備中の論文が2編あり,2年間の萌芽研究の成果としては十分なものだったと考えられる.今後は本研究で確立したウィルスDNAを唾液から検出する手法をスポーツ競技現場,中高齢者のヘルスケアの現場に応用することで,一層の研究の展開を計りたい.

Little information is available regarding the relationships among human obesity-related genes, cardiorespiratory fitness and metabolic syndrome (MS) or predisposition to MS (MP). The purpose of this study was to investigate the contribution of obese-related genes and cardiorespiratory fitness to the MS in middle-aged and old men and women. Seven hundred fifty eight healthy men and women participated in this study. We measured maximal oxygen uptake (VO2max) during an incremental cycle ergometer exercise test. Serum BDL-cholesterol, triglyceride and plasma glucose levels were measured in all subjects. Total and regional lean soft tissue and fat mass were also measured by dual-energy X-ray absorptiometry (DXA). We analysed the genotype of b3-adrenergic receptor (ADRB3 64 T>A), peroxisome proliferator-activated receptor gamma (PPARG 1431 C>. Pro12Ala), uncoupling protein 1(UCP1 3826 A>G), and fatty acid-binding protein 2(FABP2 54 A>T) using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Significant associations were observed between VO2max less than 32 nil/kg/min in men and 30 ml/kg/min in women and increases in the number of risk factors of MS (P<0.05). Poor VO2max was associated with the prevalence of MS in men and women independently of the 1431 C>T polymorphism in PPAR_Y. It is important to maintain high cardiorespiratory fitness regardless of the obesity gene variance for the prevention of metabolic syndrome.

INTRODUCTION : The non-contact anterior cruciate ligament (ACL) injuries often occur in cutting or single limb landing movement. From the video analysis it appears forceful valgus collapse occurred combined with external foot rotation. On the other hand from bone bruises of MRI and arthroscopic findings it looks the valgus knee impingement combined with the anterior internal rotation of the tibia occurred. The purpose of this study was to prove that internal rotation and abduction of the tibia occur during single limb landing.
METHODS : ten healthy athletes (5male 5female age : 22yrs) participated in this study. All subjects performed a drop landing from a platform 30cm in height. Each trial was recorded using VICON system (Oxford Metrics, Inc). Data were processed using point cluster technique (Andriacchi 1998) with 24 makers on the stance limb. Internal/external rotation and adduction/abduction of the tibia with respect to the femur was analyzed during the first 150ms after toe contact.
RESULTS : all subjects experienced internal rotation of the tibia after a toe contact. About in 50ms after a toe contact, internal rotation of the tibia was maximum degree. The value was 6.1±1.2deg for female and 3.3±0.8deg for males. The female showed significantly larger value that the male (p=0.002). Almost subjects experienced abduction of the tibia after toe contact (4.1±2.7deg for females, 4.9±3.5deg for males).
DISCUSSION & SUMMARY : the increase of the internal tibial rotation with knee valgus lets increase the strain of ACL. This phenomena can be one of the reasons for female athletes have higher risk of ACL injuries than males. This study has shown that the most likely mechanism of non-contact ACL injuries is internal rotation of the tibia combined with knee valgus.

Development of SIgA kit
We tried to develop a SIgA measurement kit by using commercially available monoclonal antibody. However, we could not develop an optimal system of SIgA measurement, because of the titer and/or epitope of monoclonal antibody. So, we are trying to make some monoclonal antibodies to be able to use TIA. Now we are screening the antibody
Determination of the relationship between SIgA level and URTI
Our research which we pointed out the relationship between SIgA and URTI, was published in Japanese Journal of Clinical Sports Medicine. Furthermore, another research which dealt with changes of SIgA and physical and mental stress was published in Medicine and Science in Spurts and Exercise. Resulting from this study, we clarified that there is a certain relationship between SIgA level and risk of URTI, we may be able to apply the relationship to prevent URTI in athletes

骨格筋は活動量の増大や代謝の変化に応じて、その「量」と「質」を変化させる。本稿では、骨格筋の「質」との関連の深い骨格筋の収縮・代謝特性における可塑性に関して、主に筋活動によって誘導されるシグナル伝達経路と可塑性制御においてキーとなる分子について概説する。最後に最近明らかになってきたマイクロRNAの筋収縮・代謝特性への関与についても触れる。(著者抄録)

骨格筋は、多様な外的刺激に適応し、自身の収縮・代謝特性を変化させる高い可塑性を有している。これまでの多くの研究から、転写コアクチベーターであるPeroxisome proliferator-activated receptor γ coactivator-1α(PGC-1α)が、骨格筋の可塑性を制御する中心的な分子の1つであることが理解されている。PGC-1αは、筋ミトコンドリア新生などの収縮・代謝特性の制御に加え、種々の因子を介して骨格筋を栄養する毛細血管ネットワークの再構築にも関与するなど、その作用は広範にわたる。(著者抄録)

Mitochondria play a central role in energy production but also are the main cellular source of reactive oxygen species (ROS). It is widely believed that aging is related to the accumulation of oxidative molecular damage due to ROS. Aging also induces a decrease in muscle function. Recent studies indicate that caloric restriction and physical exercise suppress the decrease in muscle function though the maintaining quality of mitochondria. This review provides the current understanding of the influence of caloric restriction and exercise on mitochondrial quality control in skeletal muscle.

骨格筋はおもに遅筋線維、速筋線維の2つの線維から構成され、これらの線維が各筋ごとに一定の割合でモザイク状に配列している。遅筋線維はおもに糖質および脂質の有酸素的な代謝を行い、収縮速度は遅いが疲労耐性が高い。一方の速筋線維は主として糖質の無酸素的分解をATP再合成に用い、収縮速度は速いが疲労しやすい。骨格筋の収縮特性は優位に発現しているミオシン重鎖によって規定されている。齧歯類の遅筋はおもに1型と2A型ミオシン重鎖、速筋は2X型、2B型ミオシン重鎖を発現している。骨格筋の収縮・代謝特性はスポーツ活動によりダイナミックに変化する。たとえば、持久性トレーニングによって骨格筋の筋線維タイプが速筋型から遅筋型へと変化することが知られている。スポーツ活動による筋線維タイプ移行のメカニズムは完全には明らかではないが、筋収縮に伴う細胞内カルシウム関連のシグナル伝達がこの過程に重要な役割を果たしていると考えられている。(著者抄録)

近年のmicroRNA(miRNA)の発見と、血中にmiRNAが安定に存在しているという知見は、バイオマーカーとしてのmiRNAの可能性を示した。さらに最近、血中に分泌されたmiRNAが他所にて遺伝子発現を抑制しうると報告されるに及び、従来のホルモンやサイトカインを中心とした細胞間情報伝達の概念は大きく変更を余儀なくされる可能性がある。そこで本総説では、血中miRNAの種類や機能について概説し、バイオマーカーとしてのmiRNAに関する最新の知見をまとめ、身体運動の影響を含めたストレス負荷条件における変化や予測される機能に関して概説する。(著者抄録)

Bone tissue is constantly deconstructed by osteoclasts and reconstructed by osteoblasts. This dynamic metabolism makes bone mass stable. After menopause, rapid bone loss is commonly occurred by a decrease in circulating estrogen, leading to osteoporosis. Exercise (mechanical loading) can effectively prevent the rapid bone loss. On the other hand, the exercise also increases circulating sex steroid hormones such as dehydroepiandrosterone (DHEA) and estradiol (E_2). The exercise-induced circulating sex steroid hormones may be of significance for mechanical loading-induced changes in bone metabolism. This short review focuses on role of the sex steroid hormones in the process of mechanical loading-induced bone metabolism among elderly women.

Skeletal muscle is the dominant organ in locomotion and energy metabolism so that maintaining skeletal muscle function is a prerequisite for our health and independent living throughout the life. A loss or decrease in skeletal muscle function leads to increased morbid-ity and mortality through the development of secondary diseases such as metabolic syndrome, type 2 diabetes, obesity, cardiovascular and respiratory disease. Identifying mechanisms which influence the processes regulating skeletal muscle function is a key priority. The recent discov-ery of microRNAs (miRNAs) provides a new knowledge controlling skeletal muscle function. miRNAs suppress gene expression through either in inhibition of protein translation or in deg-radation of the mRNA transcripts through a process similar to RNA interference (RNAi). This review provides the current understanding in skeletal muscle miRNA biology and focuses on their role and regulation under physiological conditions with exercise.

Shimizu, K, Aizawa, K, Suzuki, N, Masuchi, K, Okada, H, Akimoto, T, Mesaki, N, and Akama, T. Influences of weight loss on monocytes and T-cell subpopulations in male judo athletes. J Strength Cond Res 25(7): 1943-1950, 2011-The purpose of this study was to examine weight loss effects on immune function in judo athletes. Six elite male Japanese judo athletes (20.3 +/- 0.4 years) were enrolled in this study. They completed usual weight loss programs during 2 weeks preceding an actual competition. Subjects noted the appearance of upper-respiratory tract infection (URTI) symptoms during the study period. Blood samples were obtained at 40 (baseline period: BL) and 3 (weight loss period: WL) days before and 1 day after the competition (AC). The CD3(+), CD4(+), CD8(+), CD56(+)CD3(-), CD28(+)CD4(+), CD28(+)CD8(+), and Toll-like-receptor-4(+) (TLR-4) CD14(+) cells were counted by using flow cytometer analysis. The 6 subjects reported 1 headache, 3 runny nose conditions, and 1 coughing instance during the WL. The CD3(+), CD4(+), CD8(+), and CD28(+)CD4(+) cell counts were significantly lower at WL than at BL (p <= 0.05); they reverted to the baseline value at AC. The TLR-4(+)CD14(+) cells were significantly fewer at WL (p <= 0.05); they remained fewer than they had been at BL, even at AC. These results suggest that 2 weeks of weight loss before a competition can impair cell-mediated immune function and induce high susceptibility to URTI in judo athletes. Coaches, support staff, and athletes should monitor athletes' weight loss, hydration status, appearance of URTI symptoms, and immunocompetence such as lymphocytes and monocytes to prevent the physical condition from becoming worse.

Epidemiological studies suggest that highly trained athletes are more susceptible to upper respiratory tract infections (URTI) compared with the general population. Upper respiratory symptoms (URS) often appear as either primary invasion of pathogenic organisms and/or reactivation of latent viruses such as Epstein-Barr virus (EBV). The purpose of this study was to examine the relationship between EBV reactivation and the appearance of URS during intensive training in collegiate rugby football players. We evaluated EBV-DNA expression in saliva and examined the relationship between onset of URS and daily changes in EBV-DNA as well as secretory immunoglobulin A (SIgA) levels among 32 male collegiate rugby football players during a 1-month training camp. The EBV-DNA expression tended to be higher in subjects who exhibited sore throat (p=0.07) and cough (p=0.18) than that of those who had no symptoms, although their differences were not significant. The SIgA level was significantly lower 1 day before the EBV-DNA expression (p&lt
0.05). The number of URS increased along with the EBV-DNA expression and decrease of SIgA levels. These results suggest that the appearance of URS is associated with reactivation of EBV and reduction of SIgA during training. © 2010 Georg Thieme Verlag KG Stuttgart · New York.

Kon, M, Iizuka, T, Maegawa, T, Hashimoto, E, Yuda, J, Aoyanagi, T, Akimoto, T, and Takahashi, H. Salivary secretory immunoglobulin A response of elite speed skaters during a competition period. J Strength Cond Res 24(8): 2249-2254, 2010-We aimed to determine the responses of salivary secretory immunoglobulin A (SIgA) and the incidence of upper respiratory tract infections (URTI) symptoms among elite speed skaters during an actual competition period. The subjects were 8 international-class elite speed skaters. Saliva samples were obtained 3, 2, and 1 days before the race, the day of the race, and 1 day after the race. Salivary secretory immunoglobulin A concentration was measured by enzyme immunoassay, and SIgA secretion rate was calculated. A visual analogue scale was used to subjectively assess fatigue and tension. Daily URTI symptoms were recorded by using a questionnaire. There was no statistically significant difference in the saliva flow rate (p = 0.69), SIgA concentration (p = 0.07), and subjective fatigue (p = 0.07) during the competition period. The SIgA secretion rate recorded for the day of the race was significantly high compared with that of 3 and 2 days before and 1 day after the race (p < 0.05). The subjective tension recorded on the race day was significantly high compared with that for 3, 2, and 1 days before the race (p < 0.05). Two subjects exhibited URTI symptoms after the race. These findings suggest that salivary SIgA in elite speed skaters increased after a tapering period and that an actual high-intensity speed skating race decreased salivary SIgA in elite speed skaters. These data also suggest that the incidence of URTI symptoms might be related to the SIgA level. Coaches may need to take precautions after competitions to minimize their athletes' contact with cold viruses and adjust training load for a few days after competition to improve the decreased mucosal immune function.

KON, M., T. IKEDA, T. HOMMA, T. AKIMOTO, Y. SUZUKI, and T. KAWAHARA. Effects of Acute Hypoxia on Metabolic and Hormonal Responses to Resistance Exercise. Med. Sci. Sports Exerc., Vol. 42, No. 7, pp. 1279-1285, 2010. Introduction: Several recent studies have shown that resistance exercise combined with vascular occlusion effectively causes increases in muscular size and strength. Researchers speculated that the vascular occlusion-induced local hypoxia may contribute to the adaptations via promoting anabolic hormone secretions stimulated by local accumulation of metabolic subproducts. Here, we examined whether acute systemic hypoxia affects metabolic and hormonal responses to resistance exercise. Methods: Twelve male subjects participated in two experimental trials: 1) resistance exercise while breathing normoxic air [normoxic resistance exercise (NR)] and 2) resistance exercise while breathing 13% oxygen [hypoxic resistance exercise (HR)]. The resistance exercises (bench press and leg press) consisted of 10 repetitions for five sets at 70% of maximum strength with 1-min rest between sets. Blood lactate, serum growth hormone (GH), epinephrine (E), norepinephrine (NE), insulin-like growth factor 1, testosterone, and cortisol concentrations were measured before normoxia and hypoxia exposures, 15 min after the exposures, and at 0, 15, 30, and 60 min after the exercises. Results: Lactate significantly increased after exercises in both trials (P < 0.05). In the HR trial, GH and cortisol significantly increased after the exercise (P < 0.05) but not in the NR trial. The E, NE, insulin-like growth factor 1, and testosterone significantly increased after the exercises in both trials (P < 0.05). The mean values of lactate, GH, E, and NE after exercises were significantly higher in the HR trial than those in the NR trial (P < 0.05). Conclusions: These findings suggest that resistance exercise in hypoxic condition caused greater accumulation of metabolites and strong anabolic hormone response.

Mohawk(Mkx) is a member of the Three Amino acid Loop Extension superclass of atypical homeobox genes that is expressed in developing tendons. To investigate the in vivo functions of Mkx, we generated Mkx(-/-) mice. These mice had hypoplastic tendons throughout the body. Despite the reduction in tendon mass, the cell number in tail tendon fiber bundles was similar between wild-type and Mkx(-/-) mice. We also observed small collagen fibril diameters and a down-regulation of type I collagen in Mkx(-/-) tendons. These data indicate that Mkx plays a critical role in tendon differentiation by regulating type I collagen production in tendon cells.

In the field of athletics, acupuncture has been used for treatment of injury, reduction of fatigue and management of physical condition. However, there is little information on the effect of acupuncture on the immune function in response to exercise.Purpose The aim of this study was to examine the effect of acupuncture treatment on the mucosal immune function after a single period of intense exercise by measuring salivary immunoglobulin A (SIgA).Methods 12 healthy men (23.6 +/- SEv 0.3 years) participated in this study with a crossover design. The subjects exercised on a bicycle equipped with an ergometer at 75% VO(2)max for 60 min. Acupuncture treatment was applied at LU6, LI4, ST36 and ST6, for 30 min after the exercise. The control treatment was rest without acupuncture and that the order of the treatment was randomised. We measured parameters including saliva flow rate, SIgA concentration, SIgA secretion rate, heart rate and plasma catecholamine concentration all before the exercise and at 1 h, 2 h, 3 h, 4 h and 24 h after the exercise. The visual analogue scale for self-perceived tiredness and the profile of mood states questionnaires were recorded before the exercise and at 24 h after the exercise.Result Intense exercise-induced decrease of SIgA levels was attenuated by the acupuncture treatment. In contrast, the subjective fatigue score and psychological measurement were not affected by the acupuncture.Conclusion Acupuncture treatment may attenuate the decrease in SIgA level induced by intense exercise.

Androgens, Such as testosterone, play important roles in regulation of diverse physiological process of target tissues. Recently, we reported that steroidogenic enzymes exist in skeletal Muscle and regulate local production of testosterone in response to exercise. Testosterone is transformed into a bioactive androgen metabolite, dihydrotestosterone (DHT) by 5 alpha-reductase. However, it is unclear whether exercise stimulates local bioactive androgen metabolism in the skeletal muscle in both sexes. In the present study, we examined sex differences in the levels of dehydroepiandrosterone (DHEA), free testosterone, DHT, and steroidogenesis-related enzymes 5 alpha-reductase and androgen receptor (AR) in rat's skeletal muscle before and after a single bout of exercise. Basal muscular free testosterone and DHT levels were higher in males than females, whereas the levels of DHEA did not differ between the sexes. Muscular DHEA, free testosterone, and DHT levels were increased in both sexes after the exercise. There were no differences of 5 alpha-reductase and AR transcripts and proteins between the sexes, and the expression of 5 alpha-reductase was significantly increased in both sexes after the exercise. Finally, the expression of AR was significantly higher in female rats, but not in males after the exercise. These data Suggest that acute exercise enhances the local bioactive androgen metabolism in the skeletal Muscle of both sexes. (C) 2009 Elsevier Inc. All rights reserved.

Aim. The authors hypothesized that inconsistent SIgA response to exercise is caused by the different adaptative status of subjects to a cold environment. The purposes of the study were to examine whether moderate-intense exercise in a cold environment decreases SIgA and whether adaptation to a cold environment has any effect on SIgA.
Methods. Young male skaters, short track (N=9) and inline (N=10), participated in this study. All subjects cycled for 60 min at 65% (V) over dot(2max) in cold (ambient temperature: 5+/-1 degrees C, relative humidity 41+/-9%) and thermoneutral (ambient temperature: 21+/-1 degrees C, relative humidity 35+/-5%) conditions. Saliva samples were collected as follows: before and after 1 hour of environmental exposure; immediately, 30-min, 60-min and 120-min after the exercise.
Results and conclusion. Salivary SIgA and saliva flow rate decreased after the exercise in both groups only in thermoneutral conditions. The SIgA secretion rate did not decrease after moderate-high intensity exercise in a cold environment, and the SIgA response to exercise was not affected by the different adaptative status of subjects to the cold environment.

生体には常に様々な物理刺激が負荷されており,それらの刺激に応答して生体機能が調節されていることや,生体組織の維持・再構築が行われていることが徐々に明らかになってきた。本稿では伸展刺激や静水圧刺激が細胞の機能や分化に与える影響について論じ,再生医工学における物理刺激の利用例を紹介する。再生医工学において,物理刺激負荷は培養細胞の分化コントロールの手段として,成長因子などの生化学的刺激および培養担体などの材料からの刺激に並んでティッシュエンジニアリングに適用されていくことが期待される。(著者抄録)

中高齢女性を対象として、日常の身体活動量の違いが口腔内粘膜免疫能および全身免疫能に及ぼす影響を検討した。健康な中高齢女性101例を対象とした。計測した歩数を階層化し、3分位数値によって3等分することで3群(T1、T2、T3)に分けた。SIgA分泌量およびT細胞の各サブセットにおいて身体活動レベルによる影響の違いは認めなかった。T1群はT2群に比べて明らかに低い身体活動量を維持していた。T2群の歩数は60歳代の平均歩数にやや近似した。また、T1群の歩数は一般に比べても低い値であった。年齢と唾液SIgA分泌速度の間に弱いながらも有意な負の相関関係を認めた。CD28発現Th細胞数と年齢との間には、有意ではないが弱い負の相関関係を認めた。CD28発現と日常の身体活動量の間に関係がない可能性が考えられた。身体活動量と各免疫学的指標との間に関係を認めなかった。

大学ラグビー選手32例を対象とし、約1ヵ月間の夏期合宿期間における日毎の唾液中分泌型免疫グロブリンA(SIgA)の変動及び上気道感染症(URTI)症状の有無や主観的な疲労状態について調査し、SIgAの変動との関連性について検討した。唾液分泌速度は合宿開始から7、8日目と12、13日目、16日目においてBaselineと比較して有意に低下した。SIgA濃度は期間中を通し、いずれの日においてもBaselineと比較して有意差は認めなかった。SIgA分泌速度は合宿開始から8日目と11、12日目においてBaselineと比較して有意に低下した。URTI症状を有した期間のSIgA分泌速度は症状を有していなかった期間と比較して、有意に低値を示した。主観的疲労感は合宿開始から2、3、6、9、10、19日目においてBaselineと比較して有意に増加した。

Objective.-Considering the adverse effects of exercise-induced cortisol secretion on health in athletes, it is important to determine the environmental and individual factors that contribute to the variations in exercise-induced cortisol secretion. In this study, the effects of cold environment exposure and cold acclimatization on exercise-induced salivary cortisol responses were investigated. Methods.-Short track skaters (n = 11), who usually practice under cold conditions, and inline skaters (n = 11), who usually practice under room temperature conditions, participated in a randomized crossover study. All participants cycled for 60 minutes at 65% V̇o2 max under cold (ambient temperature: 5 ± 1°C, relative humidity 41% ± 9%) and room temperature (ambient temperature: 21 ± 1°C, relative humidity 35% ± 5%) conditions. The participants had a 120-minute bed rest recovery phase at room temperature after both exercise bouts. Cortisol levels were measured in saliva samples collected pre-exercise and postexercise at 1 minute, 30 minutes, 60 minutes, and 120 minutes. Results.-Both short track and inline skaters exhibited clear cortisol responses to exercise under cold and room temperature conditions. The magnitude of the cortisol response, however, was different between skaters and conditions. The inline skaters exhibited significantly higher cortisol values under cold conditions than under room temperature conditions (7.6 nmol/L and 4.2 nmol/L, respectively). However, the short track skaters exhibited significantly higher cortisol values under cold conditions compared to room temperature conditions (8.7 nmol/L and 5.4 nmol/L, respectively). Conclusions.-The effects of cold environment exposure on exercise-induced cortisol response were different between skaters who usually practice under cold or room temperature conditions. These results can be interpreted as acclimatization to either cold or room temperature conditions attenuating the cortisol response, suggesting that acclimatization may be beneficial in reducing the exercise-induced cortisol response. © 2009 Wilderness Medical Society.

intensive physical exercise may cause muscular injury and increase oxidative stress. The purpose of this study was to examine the effect of an antioxidant. coenzyme Q(10) (CoQ(10)), on muscular injury and oxidative stress during exercise training. Eighteen male students, all elite Japanese kendo athletes. were randomly assigned to either a CoQ(10) group (n 10) or a placebo group n 8) in a double-blind manner. Subjects in the CoQ(10) group took 300 mg CoQ(10) per d for 20d, while subjects in the placebo group took the same dosage of a placebo. All subjects practised kendo 5.5 h per d for 6d during the experimental period. Blood samples were taken 2 weeks before, during (1d, 3d, 5d) and I week after the training. Serum creatine kinase (CK) activity and myoglobin (Mb) concentration significantly increased in both groups (at 3d and 5d). Serum CK (at 3d), Mb (at 3d) and lipid peroxide (at 3d and 5d) of the CoQ(10) group were lower than those of the placebo group. The leucocyte counts in the placebo group significantly increased (at 3d) and neutrophils significantly increased in both groups (at 3d and 5d). Serum scavenging activity against superoxide anion did not change in either group. These results indicate that CoQ(10) supplementation reduced exercise-induced Muscular injury in athletes.

近年、メカニカルストレスが細胞の機能や分化に与える影響が注目されるようになってきた。本稿では再生医工学におけるメカニカルストレス利用の例として、静水圧が再生軟骨に与える影響について論じる。現在、関節軟骨組織の再構築のためには、in vitroでの培養・増殖に伴い脱分化した軟骨細胞を再分化させる基盤技術が必要となる。関節軟骨組織に生理的に負荷されている静水圧という物理刺激下での培養は、脱分化した軟骨細胞の再分化において促進的な効果がある。メカニカルストレスによる細胞の分化コントロールは、再生医療において汚染の原因となる外来因子を必要としない再生医工学の新たなアプローチとなる可能性があると考えられる。(著者抄録)

Realtime optical bioluminescence imaging is a powerful tool for studies of gene regulation in living animals. To elucidate exercise-induced signaling/transcriptional control of the peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (Pgc-1 alpha) gene in skeletal muscle, we combined this technology with electric pulse-mediated gene transfer to cotransfect the Pgc-1 alpha reporter gene with plasmid DNA encoding mutant/deletion forms of putative regulatory factors and, thereby, assess the responsiveness of the promoter to skeletal muscle contraction. We show that each of the myocyte enhancer factor 2 sites on the Pgc-1 alpha promoter is required for contractile activity-induced Pgc-1 alpha transcription. The responsiveness of the Pgc-1 alpha promoter to contractile activity could be completely blocked by overexpression of the dominant-negative form of activating transcription factor 2 (ATF2), the signaling-resistant form of histone deacetylase (HDAC) 5 (HDAC5), or protein kinase D (PKD), but not by HDAC4. These findings provide in vivo evidence for functional interactions between PKD/HDAC5 and ATF2 regulatory factors and the Pgc-1 alpha gene in adult skeletal muscle.

We aimed to develop a valid model of immunosuppression induced by intense exercise in rats. Rats were divided into three groups. In the rest (Rest) group, saliva was collected from resting rats on 4 consecutive days. In the exercise (Ex) group, rats ran on a treadmill untill exhaustion (exercise time: 60.0 +/- 3.7 min), and their saliva was collected before and after exercise; the salivary glands were removed after exercise. In the control (Con) group, saliva collection and gland removal were also performed, but the rats did not exercise. Secretory immunoglobulin A (SIgA) concentrations in saliva and polymeric immunoglobulin receptor (pIgR) mRNA expression in the glands were measured. There was no significant change in SIgA concentration in the Rest group over 4 days. In the Ex group, SIgA concentration decreased significantly after exercise compared with before, whereas there was no significant change in the Con group. The expression of pIgR mRNA was significantly lower in the Ex group post-exercise than in the Con group. Our procedure for saliva collection appeared suitable, and the exercise-induced SIgA suppression was probably caused by a decline in pIgR mRNA expression. We propose to use this reproducible and reliable rat model of exercise-induced SIgA suppression in future studies.

In vivo protein kinases A and G (PKA and PKG) coordinately phosphorylate a broad range of substrates to mediate their various physiological effects. The functions of many of these substrates have yet to be defined genetically. Herein we show a role for smoothelin-like protein 1 (SMTNL1), a novel in vivo target of PKG/PKA, in mediating vascular adaptations to exercise. Aortas from smtnl1(-/-) mice exhibited strikingly enhanced vasorelaxation before exercise, similar in extent to that achieved after endurance training of wild-type littermates. Additionally, contractile responses to alpha-adrenergic agonists were greatly attenuated. Immunological studies showed SMTNL1 is expressed in smooth muscle and type 2a striated muscle fibers. Consistent with a role in adaptations to exercise, smtnl1(-/-) mice also exhibited increased type 2a fibers before training and better performance after forced endurance training compared smtnl1(-/-) mice. Furthermore, exercise was found to reduce expression of SMTNL1, particularly in female mice. In both muscle types, SMTNL1 is phosphorylated at Ser-301 in response to adrenergic signals. In vitro SMTNL1 suppresses myosin phosphatase activity through a substrate-directed effect, which is relieved by Ser-301 phosphorylation. Our findings suggest roles for SMTNL1 in cGMP/cAMP-mediated adaptations to exercise through mechanisms involving direct modulation of contractile activity.

CD28 molecule expression on the surface of T cells plays a critical role in up-regulation of various cytokines synthesis and T-helper (Th) cell proliferation and differentiation. However aging induces a decrease in CD28 expression and unbalance of Th1/Th2, leading to impairment of Th-cell mediated immune function. The purpose of this study was to assess the affects of moderate exercise training on CD28 expression and the balance of Th1/Th2 cells in elderly people. Forty-eight elderly subjects were assigned to an exercise training group (EXC: 13 males, 15 females; aged 61-76) or a non-exercise control group (CON: 7 males, 13 females; aged 62-79). Subjects in EXC participated in exercise sessions 5-days a week for 6 months. Meanwhile, subjects in CON maintained their normal physical activity levels during the study period. Blood samples were collected before and after the training period. Samples were measured for the number of leukocytes and lymphocytes, as well as for CD3(+), CD4(+), CD28(+)CD4(+), IFN-gamma(+)CD4(+), IL-4(+)CD4(+) cells. The number of leukocytes, lymphocytes, and CD3+ cells did not change after 6 months in both EXC and CON. The number of CD4(+) and CD28(+)CD4(+) cells significantly increased after the training in EXC (P < 0.05), while CON did not show significant changes. In the EXC group, IFN-gamma(+)CD4(+) cell numbers were significantly higher following the training (P < 0.05), but the number of IL-4(+)CD4(+) cells was not changed. In the CON group, there were no significant alterations in IFN-gamma(+)CD4(+) and IL-4(+)CD4(+) cell numbers. In conclusion, moderate exercise training in the elderly is associated with improvement of expression of CD28 on Th cells and Th1/Th2 balances. Therefore, exercise training could up-regulate Th cell-mediated immune functions and be helpful for a decrease in the risk of infections and autoimmune diseases in elderly people.

Endurance exercise promotes mitochondrial biogenesis in skeletal muscle possibly by inducing peroxisome proliferator-activated receptor gamma coactivator la gene transcription through activation of the p38 mitogen-activated protein kinase pathway. A novel imaging analysis revealed the importance of activating transcription factor 2 and histone deacetylase 5/myocyte enhancer factor 2 in the regulation of the Pgc-1 alpha gene in skeletal muscle in vivo.

Purpose: The aim of this work was to assess the relationship in elderly subjects between free-living daily physical activity and mucosal immunity, especially salivary secretory immunoglobulin A (SIgA). Methods: Elderly volunteers (114 men and 170 women) aged 71.3 +/- 0.3 yr (range: 65-86 yr) participated in this study. Resting saliva samples were collected in the morning. Saliva samples stimulated by chewing a sterile cotton ball at a frequency of 60/60 s were collected. The SIgA concentration was measured using enzyme-linked immunosorbent assay (ELISA), and the SIgA secretion rate was calculated. Free-living step count (steps per day), energy expenditure (kJ(.)kg(-1)-d(-1)), and activity durations (min(.)d(-1)) at specific intensity levels (inactive, light, moderate, and vigorous) were evaluated using an electric pedometer. The data obtained were stratified by pedometer-determined steps per day using quartiles (Q1-Q4) for distribution. Results: Elderly in quartiles showed step counts of 2962 94, 5118 62, 6832 59, and 9951 264 steps per day. Significant differences were found in the mean step count (P < 0.0001), energy expenditure (P < 0.0001), and activity duration (P < 0.0001) with increasing pedometer-determined activity quartiles. Both SIgA concentration and SIgA-secretion rate were significantly higher for Q3 than for Q1 (P < 0.05). Meanwhile, saliva flow rates showed no significant differences across quartiles. Conclusion: These results suggest that a free-living daily physical activity level of approximately 7000 steps per day might be regarded as a moderate daily physical activity target for elderly people to improve mucosal immune function.

The purpose of this study was to examine oxidative stress in skeletal muscle after eccentric and concentric muscle contractions. Eight-week-old Institute of Cancer Research (ICR) mice (n = 90) were divided into 3 groups: eccentric muscle contraction group (ECC, n = 42), concentric muscle contraction group (CON, n = 42), and control group (pre, n = 6). The tibialis anterior muscle was stimulated via the peroneal nerve to contract either eccentrically or concentrically. The tibialis anterior muscle was isolated before and 0, 6, 12, 18, 24, 72, and 168 h after muscle contraction. Immediately after muscle contractions, thiobarbituric acid reactive substances (TBARS) in skeletal muscle significantly increased (p < 0.05) in both ECC and CON conditions. However, in the ECC group alone, the TBARS level peaked at 12 and 72 h after the contractions. There was greater migration of mononuclear cells in ECC than in CON muscle. In addition, there was a correlation between TBARS in skeletal muscle and migration of mononuclear cells in ECC muscle (r = 0.773, p < 0.01), but this correlation was not apparent in CON muscle (r = 0.324, p = 0.12). The increased mononuclear cells may reflect inflammatory cells. These data suggest that eccentric muscle contraction induces greater oxidative stress in skeletal muscle, which may in turn be due to enhanced generation of reactive oxygen species (ROS) by migrating inflammatory cells.

Aim: We aimed to examine the effect of Coenzyme Q(10) (CoQ(10)) supplementation on the exhaustive exercise-induced injury and oxidative stress in skeletal muscle and liver.Methods: Rats were divided into four groups: rest group [control (Con)-Rest; n = 6)], exercise group (Con-Ex; n = 6), rest group with CoQ(10) supplement (CoQ(10)-Rest; n = 6), and exercise group with CoQ(10) supplement (CoQ(10)-Ex; n = 6). The exercise groups were run on a treadmill until exhaustion. The CoQ(10) supplemented groups received an oral administration of CoQ(10) (300 mg kg(-1), 4 weeks). After 4 weeks, total CoQ concentration, creatine kinase (CK), glutamic-oxaloacetic transaminase (GOT), malondialdehyde (MDA), scavenging activity against reactive oxygen species [ROS; superoxide anions (0(2)(.-)) and hydroxyl radicals (HO.)] were measured.Results: Total CoQ concentration in plasma, slow-twitch muscles (soleus and gastronemius deep portion), and liver were significantly increased by CoQ(10) supplementation. Plasma CK was significantly higher in Con-Ex compared with Con-Rest, whereas there was no difference between CoQ(10)-Rest and CoQ(10)-Ex. There were no significant differences in muscle MDA in each group. Plasma GOT and liver MDA in exercise groups were significantly higher than that of rest groups, but not significantly different between CoQ(10) supplemented groups and control groups. CoQ(10) supplementation was not able to favorably influence ROS scavenging activity in skeletal muscle and liverConclusions: These data indicated that CoQ(10) supplementation increased total CoQ concentration in the slow-twitch muscles, and was useful for reducing exhaustive exercise-induced muscular injury by enhancing stabilization of muscle cell membrane.

Aim. The purpose of this study was to investigate the relationship between the influence of music on RPE during sub-maximal exercise and on the autonomic nervous system before and after sub-maximal exercise.
Methods. Heart rate (HR), HR variability (HRV) and rates of physical fatigue (RPE) during exercise at 60% and at 40% (V) over dot O-2max with and without music were measured. The exercise protocol consisted of a 30-min seated rest (control) period followed by a 30-min submaximal cycling exercise and a 35-min recovery period. Autonomic-nervous activity was measured before and after exercise. During exercise, RPE was recorded every 3 min and HR was recorded for every minute.
Results. Although RPE did not differ during exercise at 60% (V) over dot O-2max, this value was lower during exercise at 40% (V) over dot O-2max in the presence, than in the absence of a favorite piece music (P&lt;0.05). HR, HFA and LFA/HFA of HRV significantly differed with exercise intensity in the absence (P&lt;0.05), but not in the presence of music.
Conclusions. These findings suggested that music evokes a "distraction effect" during low intensity exercise, but might not influence the autonomic nervous system. Therefore, when jogging or walking at comparatively low exercise intensity, listening to a favorite piece of music might decrease the influence of stress caused by fatigue, thus increasing the "comfort" level of performing the exercise.

Aim. The purpose of this study was to investigate the relationship between the influence of music on RPE during sub-maximal exercise and on the autonomic nervous system before and after sub-maximal exercise.
Methods. Heart rate (HR), HR variability (HRV) and rates of physical fatigue (RPE) during exercise at 60% and at 40% (V) over dot O-2max with and without music were measured. The exercise protocol consisted of a 30-min seated rest (control) period followed by a 30-min submaximal cycling exercise and a 35-min recovery period. Autonomic-nervous activity was measured before and after exercise. During exercise, RPE was recorded every 3 min and HR was recorded for every minute.
Results. Although RPE did not differ during exercise at 60% (V) over dot O-2max, this value was lower during exercise at 40% (V) over dot O-2max in the presence, than in the absence of a favorite piece music (P&lt;0.05). HR, HFA and LFA/HFA of HRV significantly differed with exercise intensity in the absence (P&lt;0.05), but not in the presence of music.
Conclusions. These findings suggested that music evokes a "distraction effect" during low intensity exercise, but might not influence the autonomic nervous system. Therefore, when jogging or walking at comparatively low exercise intensity, listening to a favorite piece of music might decrease the influence of stress caused by fatigue, thus increasing the "comfort" level of performing the exercise.

The purpose of this study was to evaluate the conditioning of elite mogul skiers through the 2001-2002 Federation International de Ski season (that is, the World Cup freestyle competition and the Salt Lake City Winter Olympic Games) using a single-case study method. Four elite mogul skiers were observed independently and measured in parameters such as athletic condition. The results indicated that during the competition season there was no significant change in the conditioning of the world-class skiers of this group. However, the conditioning of the intermediate skiers did change. It was concluded that it is preferable to use the single-case study method when analyzing physical conditioning.

Transcriptional profiling in mouse skeletal muscle following a single bout of voluntary running: evidence of increased cell proliferation. J Appl Physiol 99: 2406-2415, 2005. First published August 4, 2005; doi: 10.1152/japplphysiol.00545.2005.-Skeletal muscle undergoes adaptation following repetitive bouts of exercise. We hypothesize that transcriptional reprogramming and cellular remodeling start in the early phase of long-term training and play an important role in skeletal muscle adaptation. The aim of this study was to define the global mRNA expression in mouse plantaris muscle during (run for 3 and 12 h) and after (3, 6, 12, and 24 h postexercise) a single bout of voluntary running and compare it with that after long-term training (4 wk of running). Among 15,832 gene elements surveyed in a high-density cDNA microarray analysis, 900 showed more than twofold changes at one or more time points. K-means clustering and cumulative hypergeometric probability distribution analyses revealed a significant enrichment of genes involved in defense, cell cycle, cell adhesion and motility, signal transduction, and apoptosis, with induced expression patterns sharing similar patterns with that of peroxisome proliferator activator receptor-gamma coactivator-1 alpha and vascular endothelial growth factor A. We focused on the finding of a delayed (at 24 h postexercise) induction of mRNA expression of cell cycle genes origin recognition complex 1, cyclin A2, and cell division 2 homolog A (Schizoccharomyces pombe) and confirmed increased cell proliferation by in vivo 5-bromo-2'-deoxyuridine labeling following voluntary running. X-ray irradiation of the hindlimb significantly diminished exercise-induced 5-bromo-2'-deoxyuridine incorporation. These findings suggest that a single bout of voluntary running activates the transcriptional network and promotes adaptive processes in skeletal muscle, including cell proliferation.

Transcriptional profiling in mouse skeletal muscle following a single bout of voluntary running: evidence of increased cell proliferation. J Appl Physiol 99: 2406-2415, 2005. First published August 4, 2005; doi: 10.1152/japplphysiol.00545.2005.-Skeletal muscle undergoes adaptation following repetitive bouts of exercise. We hypothesize that transcriptional reprogramming and cellular remodeling start in the early phase of long-term training and play an important role in skeletal muscle adaptation. The aim of this study was to define the global mRNA expression in mouse plantaris muscle during (run for 3 and 12 h) and after (3, 6, 12, and 24 h postexercise) a single bout of voluntary running and compare it with that after long-term training (4 wk of running). Among 15,832 gene elements surveyed in a high-density cDNA microarray analysis, 900 showed more than twofold changes at one or more time points. K-means clustering and cumulative hypergeometric probability distribution analyses revealed a significant enrichment of genes involved in defense, cell cycle, cell adhesion and motility, signal transduction, and apoptosis, with induced expression patterns sharing similar patterns with that of peroxisome proliferator activator receptor-gamma coactivator-1 alpha and vascular endothelial growth factor A. We focused on the finding of a delayed (at 24 h postexercise) induction of mRNA expression of cell cycle genes origin recognition complex 1, cyclin A2, and cell division 2 homolog A (Schizoccharomyces pombe) and confirmed increased cell proliferation by in vivo 5-bromo-2'-deoxyuridine labeling following voluntary running. X-ray irradiation of the hindlimb significantly diminished exercise-induced 5-bromo-2'-deoxyuridine incorporation. These findings suggest that a single bout of voluntary running activates the transcriptional network and promotes adaptive processes in skeletal muscle, including cell proliferation.

Peroxisome proliferator-activated receptor-gamma co- activator 1 alpha (PGC1 alpha) is a promiscuous co- activator that plays a key role in regulating mitochondrial biogenesis and fuel homeostasis. Emergent evidence links decreased skeletal muscle PGC1 alpha activity and coincident impairments in mitochondrial performance to the development of insulin resistance in humans. Here we used rodent models to demonstrate that muscle mitochondrial efficiency is compromised by diet-induced obesity and is subsequently rescued by exercise training. Chronic high fat feeding caused accelerated rates of incomplete fatty acid oxidation and accumulation of beta-oxidative intermediates. The capacity of muscle mitochondria to fully oxidize a heavy influx of fatty acid depended on factors such as fiber type and exercise training and was positively correlated with expression levels of PGC1 alpha. Likewise, an efficient lipid-induced substrate switch in cultured myocytes depended on adenovirus-mediated increases in PGC1 alpha expression. Our results supported a novel paradigm in which a high lipid supply, occurring under conditions of low PGC1 alpha, provokes a disconnect between mitochondrial beta-oxidation and tricarboxylic acid cycle activity. Conversely, the metabolic remodeling that occurred in response to PGC1 alpha overexpression favored a shift from incomplete to complete beta-oxidation. We proposed that PGC1 alpha enables muscle mitochondria to better cope with a high lipid load, possibly reflecting a fundamental metabolic benefit of exercise training.

Purpose: To examine effects of local tissue cooling on contusion-induced microvascular hemodynamics and leukocytes behavior using real-time intravital microscopy. Methods: Male Wistar rats (N = 21, 130-150 g) were randomly assigned to intensive cooling group (3°C, N = 7), a moderate cooling group (27°C, N = 7), or control group (37°C, N = 7). Contusion was induced by dropping a plastic ball on exposed cremaster muscle. After 5 min, the cremaster muscle was superfused with a saline solution for 10 min at controlled temperature of either 3°C (cooling), 27°C (moderate cooling), or 37°C (control). Microvascular hemodynamics (vessel internal diameter, blood flow rate and erythrocyte velocity) and leukocyte behavior (rolling and adhesion) were measured from recorded videotapes in the same venules before and after contusion, and after cooling. Results: Cooling-induced vasoconstriction was marked at 3°C and moderate at 27°C compared with that at 37°C. Blood flow rate and erythrocyte velocity were markedly lower at 3°C compared to 37°C. At 27°C, erythrocyte velocity was higher than that at 37°C, but blood flow rate was maintained at a level similar to that at 37°C. The number of rolling and adhering leukocytes at 3°C and 27°C were significantly less than at 37°C. Conclusion: Our results suggest that local tissue cooling, similar to cryotherapy, improves edema and inflammatory reaction, and may be useful for reducing inflammatory response without inhibiting blood flow after contusion. Copyright © 2005 by the American College of Sports Medicine.

Purpose: To examine effects of local tissue cooling on contusion-induced microvascular hemodynamics and leukocytes behavior using real-time intravital microscopy. Methods: Male Wistar rats (N = 21, 130-150 g) were randomly assigned to intensive cooling group (3°C, N = 7), a moderate cooling group (27°C, N = 7), or control group (37°C, N = 7). Contusion was induced by dropping a plastic ball on exposed cremaster muscle. After 5 min, the cremaster muscle was superfused with a saline solution for 10 min at controlled temperature of either 3°C (cooling), 27°C (moderate cooling), or 37°C (control). Microvascular hemodynamics (vessel internal diameter, blood flow rate and erythrocyte velocity) and leukocyte behavior (rolling and adhesion) were measured from recorded videotapes in the same venules before and after contusion, and after cooling. Results: Cooling-induced vasoconstriction was marked at 3°C and moderate at 27°C compared with that at 37°C. Blood flow rate and erythrocyte velocity were markedly lower at 3°C compared to 37°C. At 27°C, erythrocyte velocity was higher than that at 37°C, but blood flow rate was maintained at a level similar to that at 37°C. The number of rolling and adhering leukocytes at 3°C and 27°C were significantly less than at 37°C. Conclusion: Our results suggest that local tissue cooling, similar to cryotherapy, improves edema and inflammatory reaction, and may be useful for reducing inflammatory response without inhibiting blood flow after contusion. Copyright © 2005 by the American College of Sports Medicine.

Peroxisome proliferator-activated receptor gamma co-activator 1 alpha (PGC-1 alpha) promotes mitochondrial biogenesis and slow fiber formation in skeletal muscle. We hypothesized that activation of the p38 mitogen-activated protein kinase ( MAPK) pathway in response to increased muscle activity stimulated Pgc-1 alpha gene transcription as part of the mechanisms for skeletal muscle adaptation. Here we report that a single bout of voluntary running induced a transient increase of Pgc-1 alpha mRNA expression in mouse plantaris muscle, concurrent with an activation of the p38 MAPK pathway. Activation of the p38 MAPK pathway in cultured C2C12 myocytes stimulated Pgc-1 alpha promoter activity, which could be blocked by the specific inhibitors of p38, SB203580 and SB202190, or a dominant negative p38. Furthermore, the p38-mediated increase in Pgc-1 alpha promoter activity was enhanced by increased expression of the downstream transcription factor ATF2 and completely blocked by ATF2 Delta N, a dominant negative ATF2. Skeletal muscle-specific expression of a constitutively active activator of p38, MKK6E, in transgenic mice resulted in enhanced Pgc-1 alpha and cytochrome oxidase IV protein expression in fast-twitch skeletal muscles. These findings suggest that contractile activity-induced activation of the p38 MAPK pathway promotes Pgc-1 alpha gene expression and skeletal muscle adaptation.

Peroxisome proliferator-activated receptor gamma co-activator 1 alpha (PGC-1 alpha) promotes mitochondrial biogenesis and slow fiber formation in skeletal muscle. We hypothesized that activation of the p38 mitogen-activated protein kinase ( MAPK) pathway in response to increased muscle activity stimulated Pgc-1 alpha gene transcription as part of the mechanisms for skeletal muscle adaptation. Here we report that a single bout of voluntary running induced a transient increase of Pgc-1 alpha mRNA expression in mouse plantaris muscle, concurrent with an activation of the p38 MAPK pathway. Activation of the p38 MAPK pathway in cultured C2C12 myocytes stimulated Pgc-1 alpha promoter activity, which could be blocked by the specific inhibitors of p38, SB203580 and SB202190, or a dominant negative p38. Furthermore, the p38-mediated increase in Pgc-1 alpha promoter activity was enhanced by increased expression of the downstream transcription factor ATF2 and completely blocked by ATF2 Delta N, a dominant negative ATF2. Skeletal muscle-specific expression of a constitutively active activator of p38, MKK6E, in transgenic mice resulted in enhanced Pgc-1 alpha and cytochrome oxidase IV protein expression in fast-twitch skeletal muscles. These findings suggest that contractile activity-induced activation of the p38 MAPK pathway promotes Pgc-1 alpha gene expression and skeletal muscle adaptation.

Myoblasts are able to differentiate into other mesenchymal lineages including adipocytes and osteoblasts. However, it is not known how this differentiation is normally regulated in intact animals and humans. Here, we subjected cultured C2CI2 myoblasts to cyclic mechanical stretch (20% elongation) during differentiation into adipocytes. Mechanical stretch inhibited the myoblast-toadipocyte differentiation significantly, concurrent with an enhanced expression of WntlOb mRNA. Inhibition of the Writ signaling by incubation of the myoblasts with a soluble Writ ligand, sFRP-2, abolished the inhibitory function of mechanical stretch on adipogenesis. These findings provide evidence that mechanical stretch inhibits myoblast-to-adipocyte differentiation possibly through Writ signaling. (C) 2005 Elsevier Inc. All rights reserved.

Myoblasts are able to differentiate into other mesenchymal lineages including adipocytes and osteoblasts. However, it is not known how this differentiation is normally regulated in intact animals and humans. Here, we subjected cultured C2CI2 myoblasts to cyclic mechanical stretch (20% elongation) during differentiation into adipocytes. Mechanical stretch inhibited the myoblast-toadipocyte differentiation significantly, concurrent with an enhanced expression of WntlOb mRNA. Inhibition of the Writ signaling by incubation of the myoblasts with a soluble Writ ligand, sFRP-2, abolished the inhibitory function of mechanical stretch on adipogenesis. These findings provide evidence that mechanical stretch inhibits myoblast-to-adipocyte differentiation possibly through Writ signaling. (C) 2005 Elsevier Inc. All rights reserved.

日本代表選手の国外への移動に伴うコンディションの変化とそれらへの対応策の実態について調査した.第14回アジア競技大会に参加した日本代表選手を対象とした.有効回答数は526例で,オリンピック出場経験者72例,世界選手権などの国際大会出場者は309例であった.過去の国外遠征において不快症状を訴えた競技者は全体の47.5%で,長時間の移動によりコンディションを崩した経験を持つ競技者は26.8%であった.具体的な不快症状は,下腿のむくみ,腰痛,下腿の痛みなど下半身の症状が顕著であった.長時間の移動中に崩れたコンディションが試合に影響を及ぼした割合は29.1%であった

Mammalian skeletal muscles undergo adaptation in response to alteration in functional demands by means of a variety of cellular signaling events. Previous experiments in transgenic mice showed that an active form of Ca2+/calmodulin-dependent protein kinase IV (CaMKIV) is capable of stimulating peroxisome proliferator-activated receptor gamma-coactivator 1alpha (PGC-1alpha) gene expression, promoting fast-to-slow fiber type switching and augmenting mitochondrial biogenesis in skeletal muscle. However, a role for endogenous CaMKIV in skeletal muscle has not been investigated rigorously. We report that genetically modified mice devoid of CaMKIV have normal fiber type composition and mitochondrial enzyme expression in fast-twitch skeletal muscles and responded to long-term ( 4 wk) voluntary running with increased expression of myosin heavy chain type IIa, myoglobin, PGC-1alpha, and cytochrome c oxidase IV proteins in plantaris muscle in a manner similar to that of wild-type mice. Short-term motor nerve stimulation ( 2 h at 10 Hz) likewise increased PGC-1alpha mRNA expression in tibialis anterior muscles in both Camk4(-/-) and wild-type mice. In addition, we have confirmed that no detectable CaMKIV protein is expressed in murine skeletal muscle. Thus CaMKIV is not required for the maintenance of slow-twitch muscle phenotype and endurance training-induced mitochondrial biogenesis and IIb-to-IIa fiber type switching in murine skeletal muscle. Other protein kinases sharing substrates with constitutively active CaMKIV may function as endogenous mediators of activity-dependent changes in myofiber phenotype.

Mammalian skeletal muscles undergo adaptation in response to alteration in functional demands by means of a variety of cellular signaling events. Previous experiments in transgenic mice showed that an active form of Ca 2+/calmodulin-dependent protein kinase IV (CaMKIV) is capable of stimulating peroxisome proliferator-activated receptor γ-coactivator 1α (PGC-1α) gene expression, promoting fast-to-slow fiber type switching and augmenting mitochondrial biogenesis in skeletal muscle. However, a role for endogenous CaMKIV in skeletal muscle has not been investigated rigorously. We report that genetically modified mice devoid of CaMKIV have normal fiber type composition and mitochondrial enzyme expression in fast-twitch skeletal muscles and responded to long-term (4 wk) voluntary running with increased expression of myosin heavy chain type IIa, myoglobin, PGC-1α, and cytochrome c oxidase IV proteins in plantaris muscle in a manner similar to that of wild-type mice. Short-term motor nerve stimulation (2 h at 10 Hz) likewise increased PGC-1α mRNA expression in tibialis anterior muscles in both Camk4-/- and wild-type mice. In addition, we have confirmed that no detectable CaMKIV protein is expressed in murine skeletal muscle. Thus CaMKIV is not required for the maintenance of slow-twitch muscle phenotype and endurance training-induced mitochondrial biogenesis and IIb-to-IIa fiber type switching in murine skeletal muscle. Other protein kinases sharing substrates with constitutively active CaMKIV may function as endogenous mediators of activity-dependent changes in myofiber phenotype.

In response to sustained increase in contractile activity, mammalian skeletal muscle undergoes adaptation with enhanced mitochondrial biogenesis and fiber type switching. The peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha) was recently identified as a key regulator for these adaptive processes. To investigate the sequence elements in the PGC-1alpha gene that are responsible for activity-dependent transcriptional activation, we have established a unique system to analyze promoter activity in skeletal muscle of living mice. Expression of PGC-1alpha-firefly luciferase reporter gene in mouse tibialis anterior muscle transfected by electric pulse-mediated gene transfer was assessed repeatedly in the same muscle by using optical bioluminescence imaging analysis before and after low-frequency ( 10 Hz) motor nerve stimulation. Nerve stimulation ( 2 h) resulted in a transient 3-fold increase ( P &lt; 0.05) in PGC-1&alpha; promoter activity along with a 1.6-fold increase (P &lt; 0.05) in endogenous PGC-1alpha mRNA. Mutation of two consensus myocyte enhancer factor 2 (MEF2) binding sites ( - 2901 and - 1539) or a cAMP response element (CRE) ( - 222) completely abolished nerve stimulation-induced increase in PGC-1alpha promoter activity. These findings provide direct evidence that contractile activity-induced PGC-1alpha promoter activity in skeletal muscle is dependent on the MEF2 and the CRE sequence elements. The experimental methods used in the present study have general applicability to studies of gene regulation in muscle.

The effect of ascorbic acid 2-phosphate (Asc2P) was tested on porcine and rat mature hepatocytes in vitro. Asc2P enhanced the porcine albumin mRNA expression. The albumin secretion released into the culture medium from the porcine hepatocytes was also increased by Asc2P. However, Asc2P did not give any effects to rat hepatocytes on albumin mRNA expression and albumin secretion. This result shows that Asc2P is one of the important factors to enhance porcine hepatocyte activity. © 2004 Published by Elsevier B.V.

Bone marrow-derived mesenchymal stem cells (BMDMSCs) possess pluripotent differentiation potential including differentiation into osteoblasts, chondrocytes, adipocytes, and muscle cells. Using tissue engineering technology, the treatment of osteochondral lesions has been attempted with chondrocytes differentiated from mesenchymal stem cells in vitro. However, the capability of these stem cells for chondrogenic differentiation becomes gradually decreased with the passage of cell culture. Furthermore, previous studies showed that the cells from patients with osteoarthritis (OA) seemed to have reduced chondrogenic differentiation potential. It was reported that basic fibroblast growth factor (b-FGF) retained the multilinage differentiation potential of mesenchymal cells during expansion at the monolayer culture. In this study, we determined whether the BMDMSCs from patients with osteoarthritis could maintain their capability to differentiate into chondrocytes in the presence or absence of b-FGF in culture medium. We demonstrated that the chondrogenic differentiation capability of the BMDMSCs was improved by the addition of b-FGF. We concluded that bone marrow-derived stem cells from patients with osteoarthritis might be an acceptable cell source for cartilage tissue engineering. (C) 2004 Published by Elsevier B.V.

Ligament injuries are one of most common injuries to the knee joint; however, little is known about how ligaments heal and what kinds of precursor cells participate in ligament repair. Ligament cells were thought to be members of one of the lineages from mesenchymal stem cells (MSCs). However, there have been no reports on the differentiation mechanism of MSC to ligament cells because they do not have known phenotypic markers. To identify the anterior cruciate ligament (ACL)-specific phenotypic marker, we screened a cDNA library derived from rabbit ACL cells, using the signal sequence trap by the retrovirus-mediated expression screening (SST-REX) method. We detected known clones representing 135 independent proteins. Among them, 120 were secreted proteins and 15 were membrane proteins. Some of the clones encoded proteins that have never been reported to be expressed in ACLs. Therefore, the data could provide a better understanding of ACL cells and could help in finding their phenotypic markers. (C) 2004 Published by Elsevier B.V.

The purpose of this study was to examine whether mechanical stretch altered the expression of transforming growth factor (TGF)-beta1 in cultured myogenic satellite cell. C2C12 myogenic satellite cell was plated on collagenized silastic membrane and cultured in growth medium and stretched 20% elongation for 24 h. The expression of TGF-beta1 was determined by semiquantitive reverse transcriptional polymerase chain reaction (RT-PCR) analysis. Mechanical stretch decreased myogenic regulatory factors. The expression of TGF-beta1 was increased in stretched C2C12 as compared to control. This result demonstrates that mechanical stretch inhibits myogenic differentiation by an increase of TGF-beta1 expression on C2C12 myogenic satellite cell. (C) 2004 Published by Elsevier B.V.

The purpose of this study was to examine whether mechanical stretch altered the expression of transforming growth factor (TGF)-beta1 in cultured myogenic satellite cell. C2C12 myogenic satellite cell was plated on collagenized silastic membrane and cultured in growth medium and stretched 20% elongation for 24 h. The expression of TGF-beta1 was determined by semiquantitive reverse transcriptional polymerase chain reaction (RT-PCR) analysis. Mechanical stretch decreased myogenic regulatory factors. The expression of TGF-beta1 was increased in stretched C2C12 as compared to control. This result demonstrates that mechanical stretch inhibits myogenic differentiation by an increase of TGF-beta1 expression on C2C12 myogenic satellite cell. (C) 2004 Published by Elsevier B.V.

Ligament injuries are one of most common injuries to the knee joint; however, little is known about how ligaments heal and what kinds of precursor cells participate in ligament repair. Ligament cells were thought to be members of one of the lineages from mesenchymal stem cells (MSCs). However, there have been no reports on the differentiation mechanism of MSC to ligament cells because they do not have known phenotypic markers. To identify the anterior cruciate ligament (ACL)-specific phenotypic marker, we screened a cDNA library derived from rabbit ACL cells, using the signal sequence trap by the retrovirus-mediated expression screening (SST-REX) method. We detected known clones representing 135 independent proteins. Among them, 120 were secreted proteins and 15 were membrane proteins. Some of the clones encoded proteins that have never been reported to be expressed in ACLs. Therefore, the data could provide a better understanding of ACL cells and could help in finding their phenotypic markers. (C) 2004 Published by Elsevier B.V.

Bone marrow-derived mesenchymal stem cells (BMDMSCs) possess pluripotent differentiation potential including differentiation into osteoblasts, chondrocytes, adipocytes, and muscle cells. Using tissue engineering technology, the treatment of osteochondral lesions has been attempted with chondrocytes differentiated from mesenchymal stem cells in vitro. However, the capability of these stem cells for chondrogenic differentiation becomes gradually decreased with the passage of cell culture. Furthermore, previous studies showed that the cells from patients with osteoarthritis (OA) seemed to have reduced chondrogenic differentiation potential. It was reported that basic fibroblast growth factor (b-FGF) retained the multilinage differentiation potential of mesenchymal cells during expansion at the monolayer culture. In this study, we determined whether the BMDMSCs from patients with osteoarthritis could maintain their capability to differentiate into chondrocytes in the presence or absence of b-FGF in culture medium. We demonstrated that the chondrogenic differentiation capability of the BMDMSCs was improved by the addition of b-FGF. We concluded that bone marrow-derived stem cells from patients with osteoarthritis might be an acceptable cell source for cartilage tissue engineering. (C) 2004 Published by Elsevier B.V.

The effect of ascorbic acid 2-phosphate (Asc2P) was tested on porcine and rat mature hepatocytes in vitro. Asc2P enhanced the porcine albumin mRNA expression. The albumin secretion released into the culture medium from the porcine hepatocytes was also increased by Asc2P. However, Asc2P did not give any effects to rat hepatocytes on albumin mRNA expression and albumin secretion. This result shows that Asc2P is one of the important factors to enhance porcine hepatocyte activity. (C) 2004 Published by Elsevier B.V.

This study examined changes among young females of resting serum dehydroepiandrosterone sulfate (DHEAS) concentration after an 8-week period of resistance training. Nineteen healthy untrained young females [training group: age 18.9 (0.3) years, n=10, control group: age 19.3 (1.0) years, n=9; mean (SD)] were recruited in this study. The training group participated in an 8-week resistance training program (2 days per week on nonconsecutive days). The control group did not involve in any resistance training or regular exercise during the study period. Muscular strength, anthropometry, and resting hormonal levels were measured before and after training in both groups. Serum concentrations of DHEAS, dehydroepiandrosterone (DHEA), testosterone and cortisol were measured by radioimmunoassay. Body mass (2.4%) and lean body mass (2.4%) were significantly increased in the training group (P&lt;0.05), but not in the control group. The training also significantly increased one-repetition maximum (1-RM) values (P&lt;0.05). In the training group, resting concentration of serum DHEAS significantly increased after training (P&lt;0.05). Percent change of DHEAS in the training group was greater than that of the control group (P&lt;0.05). In the training group, the change of DHEAS level was positively correlated with the change of lean body mass during the training (r=0.61; P&lt;0.05). Serum DHEA, testosterone and cortisol concentrations did not change in either group during the training. The dramatic increase of resting serum DHEAS concentration after training indicates that DHEAS might be an anabolic hormone marker of adaptation to resistance training among young females. Results are presented as mean (SD).

Introduction: Acupuncture is used to modulate the physical well-being of athletes in Asian countries. However, there is little information on the immediate effects of acupuncture treatment on physiological or psychological responses to exercise. Purpose: The purpose of this study was to examine the effect of acupuncture treatment on the physical well-being of elite female soccer players during a competition period. Methods: Subjects were divided into two groups: those who received acupuncture treatment (18.1 +/- 2.3 yr [+/-SD], N = 9) and a control group (17.7 +/- 2.8 yr, N = 12). In the treatment group, acupuncture stimulus was applied at LI 4 (Goukoku), ST 36 (Ashi-sanri) for 20 min, and ST 6 (Kyosya), LU 6 (Ko-sai) points for 15 min 4 h after the game every night during the competition period. The measured parameters included salivary secretory immunoglobulin A (SIgA) level, cortisol level in saliva, subjective rating of physical well-being, and profile of mood states (POMS). Results: The following were the main results: 1) Exercise-induced decrease of salivary SIgA and increase of salivary cortisol were inhibited by acupuncture. 2) Acupuncture improved subjective rating of muscle tension and fatigue. 3) The POMS score was modulated by acupuncture. Conclusion: These results support the effectiveness of acupuncture for physical and mental well-being of athletes.

Introduction: Acupuncture is used to modulate the physical well-being of athletes in Asian countries. However, there is little information on the immediate effects of acupuncture treatment on physiological or psychological responses to exercise. Purpose: The purpose of this study was to examine the effect of acupuncture treatment on the physical well-being of elite female soccer players during a competition period. Methods: Subjects were divided into two groups: those who received acupuncture treatment (18.1 +/- 2.3 yr [+/-SD], N = 9) and a control group (17.7 +/- 2.8 yr, N = 12). In the treatment group, acupuncture stimulus was applied at LI 4 (Goukoku), ST 36 (Ashi-sanri) for 20 min, and ST 6 (Kyosya), LU 6 (Ko-sai) points for 15 min 4 h after the game every night during the competition period. The measured parameters included salivary secretory immunoglobulin A (SIgA) level, cortisol level in saliva, subjective rating of physical well-being, and profile of mood states (POMS). Results: The following were the main results: 1) Exercise-induced decrease of salivary SIgA and increase of salivary cortisol were inhibited by acupuncture. 2) Acupuncture improved subjective rating of muscle tension and fatigue. 3) The POMS score was modulated by acupuncture. Conclusion: These results support the effectiveness of acupuncture for physical and mental well-being of athletes.

Background: The immune system declines in efficiency with advancing age, making the elderly less resistant to pathogenic microorganisms. Upper respiratory tract infection (URTI) is a common illness. Recent studies have shown that suppression of secretory immunoglobulin A (SIgA) is associated with increased incidence of URTL
Objective: To assess the effect of exercise on salivary SIgA in elderly subjects.
Methods: Forty five elderly subjects (18 men, 27 women; mean (SD) age 64.9 (8.4) years) performed both 60 minute resistance and 60 minute moderate endurance training a week for 12 months. Saliva samples were obtained before training, and at four and 12 months during the training period. Salivary SIgA concentrations were measured by enzyme linked immunosorbent assay, and the SIgA secretion rate was calculated.
Results: SlgA concentrations before training, and at four and 12 months during training were 24.7 (14.4), 27.2 (14.2), and 33.8 (18.5) mug/ml respectively. SIgA secretion rates were 29.5 (26.0), 33.8 (27.2) and 46.5 (35.1) mug/min respectively. The results indicate that both the concentration and secretion rate of SlgA significantly (p&lt;0.01) increased during 12 months of exercise in these elderly subjects.
Conclusion: Regular moderate exercise seems to enhance mucosal immune function in elderly subjects.

Background: The immune system declines in efficiency with advancing age, making the elderly less resistant to pathogenic microorganisms. Upper respiratory tract infection (URTI) is a common illness. Recent studies have shown that suppression of secretory immunoglobulin A (SIgA) is associated with increased incidence of URTI. Objective: To assess the effect of exercise on salivary SIgA in elderly subjects. Methods: Forty five elderly subjects (18 men, 27 women
mean (SD) age 64.9 (8.4) years) performed both 60 minute resistance and 60 minute moderate endurance training a week for 12 months. Saliva samples were obtained before training, and at four and 12 months during the training period. Salivary SIgA concentrations were measured by enzyme linked immunosorbent assay, and the SIgA secretion rate was calculated. Results: SIgA concentrations before training, and at four and 12 months during training were 24.7 (14.4), 27.2 (14.2), and 33.8 (18.5) μg/ml respectively. SIgA secretion rates were 29.5 (26.0), 33.8 (27.2) and 46.5 (35.1) μg/min respectively. The results indicate that both the concentration and secretion rate of SIgA significantly (p&lt
0.01) increased during 12 months of exercise in these elderly subjects. Conclusion: Regular moderate exercise seems to enhance mucosal immune function in elderly subjects.

大学男子サッカー選手31名を対象に,2ヵ月間練習前に唾液を採取し,分泌型免疫グロブリンA(SIgA)分泌速度の変動と上気道感染症の発症との関係を検討した.その結果,測定期間中に上気道感染症と判断された選手は6名で,内2名は発症前のBase lineと比較して発症後にSIgA分泌速度の低下が確認された.以上の結果より,SIgA分泌速度を定期的にモニタリングすることで上気道感染症の発症のリスク評価をできる可能性が示唆された

[Objective] The purpose of this study was to determine whether icing treatment bas an effect on muscle reaction time and functional performance of a sprained ankle. [Methods] Subjects were six persons (healthy group) and six persons who had an acute ankle sprain (patient group). Anterior talar translation and talar tilt of the six patient group were evaluated by the stress X-ray measure. Ice treatment was applied for 20 minutes. [Results] The following points were clarified: 1) Reaction times of peroneus longus (PL) and peroneus brevis (PB) for the sprained ankle group (SA) were significantly longer than those for the non-sprained ankle group (NA) (p&lt
0.05). Length of time of standing on one leg with closed eyes for SA was significantly shorter than for NA (p&lt
0.05). 2) After icing treatment, reaction time of PL for SA tended to be shorter. Furthermore, PB significantly decreased after icing treatment (p&lt
0.05). Side-steps for SA were significantly increased after icing treatment (p&lt
0.05). 3) Reaction times of PL and PB for NA significantly increased after icing treatment (p&lt
0.05). Standing on one leg with closed eyes for NA significantly decreased after icing treatment (p&lt
0.05). [Conclusion] It was shown that icing treatment of a sprained ankle leads to a shorter muscle reaction time and an increase in the number of side-steps. Therefore, it was concluded that icing treatment of a sprained ankle might be able to improve incapacitated neuromuscular function and functional performance by acute trauma.

Intercellular adhesion molecule-1 (ICAM-1) plays an important role in leukocyte migration from the circulation and intervention it sites of inflammation. We investigated the effects of various types of exercise on circulating levels OF Soluble ICAM-1 (sICAM-1) in normal healthy male adults. Plasma concentrations of sICAM-1 were measured before and after bicycle ergometer exercise at intensity or 80% maximal oxygen consumption (VO2max) (16min). 42 km endurance running and 30-min downhill running at intensity of ventilation threshold (VT). The plasma sICAM-1 level increased I day after the endurance running (12%) and downhill running (14%). but not after ergometer exercise. Plasma C-reactive protein (CRP) and creatine kinase (CK) concentrations also increased I day after running. Our data suggest that exercise associated with muscle damage and, or inflammation results in increased levels of plasma sICAM-1. The physiological significance of post-exercise high plasma sICAM-1 levels is not clear at this stage. but changes in plasma sICAM-1 may reflect the status of the immune system.

ストレスX線画像によるアイシング前と直後に足関節安定性の相違について検討した.対象は急性足関節捻挫群6名で,ストレスX線撮影法によりアイシング前と直後に足関節安定性を評価し,アイシング適用は足関節に20分間実施した.健側と患側の前方引き出し距離は,患側が大きかった.患側における前方引き出し距離は,アイシング前に比べてアイシング直後において有意に減少し,距骨傾斜角においても前方引き出し距離と同様の結果が得られた.足関節捻挫に対するアイシングは足関節安定性が改善される可能性が示唆された

[Objective] The purpose of this study was to determine whether icing treatment bas an effect on muscle reaction time and functional performance of a sprained ankle. [Methods] Subjects were six persons (healthy group) and six persons who had an acute ankle sprain (patient group). Anterior talar translation and talar tilt of the six patient group were evaluated by the stress X-ray measure. Ice treatment was applied for 20 minutes. [Results] The following points were clarified: 1) Reaction times of peroneus longus (PL) and peroneus brevis (PB) for the sprained ankle group (SA) were significantly longer than those for the non-sprained ankle group (NA) (p&lt
0.05). Length of time of standing on one leg with closed eyes for SA was significantly shorter than for NA (p&lt
0.05). 2) After icing treatment, reaction time of PL for SA tended to be shorter. Furthermore, PB significantly decreased after icing treatment (p&lt
0.05). Side-steps for SA were significantly increased after icing treatment (p&lt
0.05). 3) Reaction times of PL and PB for NA significantly increased after icing treatment (p&lt
0.05). Standing on one leg with closed eyes for NA significantly decreased after icing treatment (p&lt
0.05). [Conclusion] It was shown that icing treatment of a sprained ankle leads to a shorter muscle reaction time and an increase in the number of side-steps. Therefore, it was concluded that icing treatment of a sprained ankle might be able to improve incapacitated neuromuscular function and functional performance by acute trauma.

[Objective] The purpose of this study was to determine whether icing treatment bas an effect on muscle reaction time and functional performance of a sprained ankle. [Methods] Subjects were six persons (healthy group) and six persons who had an acute ankle sprain (patient group). Anterior talar translation and talar tilt of the six patient group were evaluated by the stress X-ray measure. Ice treatment was applied for 20 minutes. [Results] The following points were clarified: 1) Reaction times of peroneus longus (PL) and peroneus brevis (PB) for the sprained ankle group (SA) were significantly longer than those for the non-sprained ankle group (NA) (p&lt
0.05). Length of time of standing on one leg with closed eyes for SA was significantly shorter than for NA (p&lt
0.05). 2) After icing treatment, reaction time of PL for SA tended to be shorter. Furthermore, PB significantly decreased after icing treatment (p&lt
0.05). Side-steps for SA were significantly increased after icing treatment (p&lt
0.05). 3) Reaction times of PL and PB for NA significantly increased after icing treatment (p&lt
0.05). Standing on one leg with closed eyes for NA significantly decreased after icing treatment (p&lt
0.05). [Conclusion] It was shown that icing treatment of a sprained ankle leads to a shorter muscle reaction time and an increase in the number of side-steps. Therefore, it was concluded that icing treatment of a sprained ankle might be able to improve incapacitated neuromuscular function and functional performance by acute trauma.

Intercellular adhesion molecule-1 (ICAM-1) plays an important role in leukocyte migration from the circulation and intervention at sites of inflammation. We investigated the effects of various types of exercise on circulating levels of soluble ICAM-1 (sICAM-1) in normal healthy male adults. Plasma concentrations of sICAM-1 were measured before and after bicycle ergometer exercise at intensity of 80% maximal oxygen consumption (VO2max) (16 min), 42 km endurance running and 30-min downhill running at intensity of ventilation threshold (VT). The plasma sICAM-1 level increased 1 day after the endurance running (12%) and downhill running (14%), but not after ergometer exercise. Plasma C-reactive protein (CRP) and creatine kinase (CK) concentrations also increased 1 day after running. Our data suggest that exercise associated with muscle damage and/or inflammation results in increased levels of plasma sICAM-1. The physiological significance of post-exercise high plasma sICAM-1 levels is not clear at this stage, but changes in plasma sICAM-1 may reflect the status of the immune system.

The purpose of this study was to examine whether mechanical stretch alters the expression of myogenic regulatory factors in cultured myogenic satellite cells. C2Cl2 myogenic satellite cells were plated on collagenized silastic membrane and cultured in growth medium and stretched with 20% elongation for 24 h. The expressions of myogenic regulatory factors including MyoD, myogenin, myocyte nuclear factor (MNF)-alpha and -beta were determined by semiquantitive reverse transcriptional-polymerase chain reaction (RT-PCR) analysis, The expressions of MyoD and MNF-alpha were decreased in stretched C2Cl2 as compared to control condition. The expressions of myogenin and MNF-beta were not detected. These results demonstrate that mechanical stretch inhibits differentiation of C2Cl2 myogenic satellite cells to myotube in the cultured condition. (C) 2001 Elsevier Science B.V. All rights reserved.

The purpose of this study was to examine whether mechanical stretch alters the expression of myogenic regulatory factors in cultured myogenic satellite cells. C2Cl2 myogenic satellite cells were plated on collagenized silastic membrane and cultured in growth medium and stretched with 20% elongation for 24 h. The expressions of myogenic regulatory factors including MyoD, myogenin, myocyte nuclear factor (MNF)-alpha and -beta were determined by semiquantitive reverse transcriptional-polymerase chain reaction (RT-PCR) analysis, The expressions of MyoD and MNF-alpha were decreased in stretched C2Cl2 as compared to control condition. The expressions of myogenin and MNF-beta were not detected. These results demonstrate that mechanical stretch inhibits differentiation of C2Cl2 myogenic satellite cells to myotube in the cultured condition. (C) 2001 Elsevier Science B.V. All rights reserved.

女性競技選手の運動による同化ホルモン応答を検討する為,一流女性柔道選手を対象に一過性運動による唾液中DHEA濃度の変動について検討した.その結果,唾液中DHEA濃度は運動前と比べて運動中に明らかに増加した.特に女性においてはtestosteroneの末梢前駆物質であるDHEAは運動による同化ホルモン応答を反映する可能性が考えられる.スポーツ競技者のトレーニング状態あるいはコンディショニングの把握において唾液中DHEA濃度測定の有用性が示唆された

[Objective] The aim of this investigation was to evaluate serum steroid hormone responses to acute resistance exercise. [Methods] Subjects were young healthy males (n=6) and females (n=6). Each group performed three sets of 10 leg press and 10 bench press exercises at an intensity of their individual 10-repetition maximum (10RM), with I min rest between sets. Blood samples were collected before (Pre-Ex) and immediately following the exercise (P0), 30 min (P30), 60 min (P60), and 24 hours (P24 h) after the exercise. Levels of blood lactate, serum testosterone, dehydroepiandrosterone sulfate (DHEAS) and cortisol were determined. [Results] The levels of blood lactate in males and females significantly increased at P0 and P30 compared with Pre-Ex (p &lt;0.05). In males, the serum level of testosterone significantly increased at PO (p &lt;0.05), whereas in females, it significantly decreased at P0, P30, P60, P24 h. (p &lt;0.05). The level of DHEAS significantly increased at P0 in both males and females (p &lt;0.05). [Conclusion] The change in the level of testosterone was different between males and females, but that of DHEAS showed a similar pattern for both sexes. The data suggest that DHEAS could be a useful indicator for evaluating the anabolic status of acute resistance exercise in females.

10日間の剣道寒稽古期間中の一定時刻に唾液を採取し,唾液中sIgAを測定し,継続的な高強度のトレーニングが唾液中sIgAに与える影響を検討した.寒稽古の1日目,10日目に唾液分泌速度,唾液中sIgA分泌速度の有意な低下が認められた.sIgA分泌速度は寒稽古終了4日後,終了10日後では依然,低値を認めたが回復する傾向にあった

16名の健常者を対象とした持久性ランニングでは運動直後に唾液分泌速度,唾液中sIgAレベルの有意な低下が認められた.sIgAレベルは1日後にほぼ運動前の値に戻り,5日後までには完全に運動前のレベルまで回復した.唾液中ラクトフェリン,フィブロネクチンレベルは,高強度運動によって殆ど変化しなかった

1)効果を認知する割合は鍼治療の未経験者の方が低かった.鍼治療未経験者の内13.8%が鍼の適応を知らなかったと答えた. 2)スポーツ障害の経験者は全体の82.1%で,鍼治療の経験率は51.3%であったことから競技スポーツ選手の鍼治療の利用は一般の人に比べて割合,頻度共に高い.競技レベルが高くなればなるほど鍼治療の経験回数が高くなった. 3)治療部位は腰部,足首,大腿部,膝,肩の順に多かった.治療目的は西洋医学的治療法では難しい「痛みの軽減」,「筋肉のハリの除去」,「筋疲労の除去」が多かった. 4)93.6%がスポーツに理解のある鍼師ならば今後利用したいと答えた

晴眼群,弱視群に比べ体力レベルの低い全盲群では,安静時のsIgA分泌速度が有意に低かった.また,運動によって全盲群のsIgA分泌速度は増加する傾向がみられた.以上のことから全盲者は晴眼者,弱視者に比べ,運動による局所免疫能の変化が異なることが考えられる

最近，骨格筋におけるイベントが筋局所だけでなく全身の代謝調節に係っている事が明らかになるとともに，筋機能の維持が近年大きな問題になっているメタボリックシンドローム等の代謝性疾患を防ぐ手段となり得る事が明らかになってきた．特に，骨格筋は最大の血糖処理器官であり，糖のみならず脂質代謝にも重要な働きをしていることから，骨格筋におけるインスリン作用の不全，すなわちインスリン抵抗性は糖尿病をはじめとする多くの生活習慣病の発症基盤となっていると考えられる．本研究では，骨格筋組織の糖取り込み機構について解析するために，まず組織工学技術を応用した筋組織の三次元培養法を確立を試みた．その結果，脱細胞化ブダ大動脈を人工腱として利用し，コラーゲンゲルを基質とした筋芽細胞の三次元培養によって，in vitroで人工筋組織を作製する事に成功した．今後は，作製中の蛍光プローブを用いて，人工筋組織での糖取り込みを観察する．

最近，骨格筋におけるイベントが筋局所だけでなく全身の代謝調節に係っている事が明らかになるとともに，筋機能の維持が近年大きな問題になっているメタボリックシンドローム等の代謝性疾患を防ぐ手段となり得る事が明らかになってきた．特に，骨格筋は最大の血糖処理器官であり，糖のみならず脂質代謝にも重要な働きをしていることから，骨格筋におけるインスリン作用の不全，すなわちインスリン抵抗性は糖尿病をはじめとする多くの生活習慣病の発症基盤となっていると考えられる．本研究では，骨格筋組織の糖取り込み機構について解析するために，まず組織工学技術を応用した筋組織の三次元培養法を確立を試みた．その結果，脱細胞化ブダ大動脈を人工腱として利用し，コラーゲンゲルを基質とした筋芽細胞の三次元培養によって，in vitroで人工筋組織を作製する事に成功した．今後は，作製中の蛍光プローブを用いて，人工筋組織での糖取り込みを観察する．