Effect of acupuncture pretreatment on inflammatory response of exercise-induced skeletal muscle damage in rats based on TLR9/MyD88/NF-κB signaling pathway. / 基于TLR9/MyD88/NF­κBä¿¡å·é€šè·¯æŽ¢è®¨é’ˆåˆºé¢„å¤„ç†å¯¹è¿åŠ¨æ€§éª¨éª¼è‚ŒæŸä¼¤å¤§é¼ ç‚Žæ€§ååº”çš„å½±å“.

OBJECTIVES: To observe the effects of acupuncture pretreatment on toll-like receptor 9/myeloid differentiation factor 88/nuclear factor-κB (TLR9/MyD88/NF-κB) signaling pathway and inflammatory response in the rats with exercise-induced skeletal muscle damage (EIMD) and explore the underlying mechanism of this pretreatment for EIMD. METHODS: A total of 88 male SD rats were randomly divided into a blank group (8 rats), a model group (40 rats) and an acupuncture pretreatment group (40 rats). In the model group and the acupuncture pretreatment group, 5 subgroups were randomized according to the sampling time of 0, 12, 24, 48 and 72 h of modeling, with 8 rats in each one, respectively. Before modeling, in the acupuncture pretreatment group, acupuncture was delivered at bilateral "Zusanli" (ST 36) and "Guanyuan" (CV 4) for 20 min, once daily for consecutive 7 days. By one-time intermittent downhill centrifugal exercise on animal experimental treadmill, EIMD model was established in the model group and the acupuncture pretreatment group. The ultrastructure of gastrocnemius muscle was observed under transmission electron microscope. The levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the serum were detected by ELISA. The protein and mRNA expression of TLR9, MyD88 and NF-κB p65 in the gastrocnemius tissue of rats was detected by the Western blot and real-time PCR, respectively. RESULTS: Compared with the blank group, the gastrocnemius ultrastructure in the model group showed the damage of different degrees, with myofilaments disarranged and twisted, mitochondria obviously swollen and mitochondrial crista partially defected. Compared with the model group, the injury was mild, most of muscle fibers were arranged neatly and the number of mitochondria increased remarkably in the acupuncture pretreatment group. Compared with the blank group, in the model group, the serum IL-6 levels increased at 0, 12, 24 and 48 h after modeling in the rats (P<0.01), and TNF-α levels were elevated at each time point after modeling (P<0.05, P<0.01). In the acupuncture pretreatment group, the serum IL-6 levels were reduced at 12, 24 and 48 h after modeling (P<0.01, P<0.05), and the TNF-α levels decreased at 24, 48 and 72 h after modeling (P<0.01) when compared with those in the model group at the same time points separately. The serum IL-6 and TNF-α levels ascended and then tended to decline in the model group and the acupuncture pretreatment group. Compared with the blank group, the protein and mRNA expression of TLR9 and NF-κB p65 in the gastrocnemius tissue increased at 12, 24, 48 and 72 h after modeling (P<0.01, P<0.05), and the protein and mRNA expression levels of MyD88 in the gastrocnemius tissue at each time point after modeling were elevated (P<0.05, P<0.01) in the model group. When compared with the model group at the same time points, in the acupuncture pretreatment group, the protein expression of TLR9 in the gastrocnemius tissue decreased at 12, 24, 48 and 72 h after modeling (P<0.05, P<0.01), and the mRNA expression of TLR9 was declined at 24, 48 and 72 h after modeling (P<0.01, P<0.05); the protein and mRNA expression of MyD88 in the gastrocnemius decreased at 24, 48 and 72 h after modeling (P<0.01, P<0.05), and that of NF-κB p65 was reduced at 24 h and 48 h after modeling (P<0.01). The protein and mRNA expression of TLR9, MyD88 and NF-κB p65 in the gastrocnemius tissue showed a trend of decrease after increase in the model group and the acupuncture pretreatment group. CONCLUSIONS: Acupuncture pretreatment can alleviate exercise-induced skeletal muscle damage, which may be related to modulating the expression of TLR9/MyD88/NF-κB signaling pathway to inhibit the inflammatory response.

Supplementation with Spirulina platensis Prevents Uterine Diseases Related to Muscle Reactivity and Oxidative Stress in Rats Undergoing Strength Training.

Strength training increases systemic oxygen consumption, causing the excessive generation of reactive oxygen species, which in turn, provokes oxidative stress reactions and cellular processes that induce uterine contraction. The aim of this study was to evaluate the possible protective effect of Spirulina platensis (SP), an antioxidant blue algae, on the contractile and relaxation reactivity of rat uterus and the balance of oxidative stress/antioxidant defenses. Female Wistar rats were divided into sedentary (CG), trained (TG), and T + supplemented (TG50, TG100) groups. Reactivity was analyzed by AQCAD, oxidative stress was evaluated by the malondialdehyde (MDA) formation, and the antioxidant capacity was measured by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Strength training increased contractile reactivity and decreased the pharmaco-mechanical component of relaxing reactivity in rat uterus. In addition, training decreased oxidation inhibition in the plasma and exercise increased oxidative stress in the uterine tissue; however, supplementation with algae prevented this effect and potentiated the increase in antioxidant capacity. Therefore, this study demonstrated that food supplementation prevents changes in reactivity and oxidative stress induced by strength training in a rat uterus, showing for the first time, that the uterus is a target for this exercise modality and antioxidant supplementation with S. platensis is an alternative means of preventing uterine dysfunction.

Fermented Deer Blood Ameliorates Intense Exercise-Induced Fatigue via Modulating Small Intestine Microbiota and Metabolites in Mice.

Intense and excessive exercise-induced fatigue has become an important health issue and can damage intestinal health. Deer blood, as a food byproduct with nutritional value, has been found to restore physical strength. However, little is known about the antifatigue effect of fermented deer blood (FDB) on intense exercise mice. The purpose of the present study is to investigate the antifatigue effect of FDB, and whether this effect is correlated with the altered small intestinal microbiota and metabolites in exercise mice. In this study, 5-week-old male C57BL/6J mice are given treadmill exercise with or without FDB supplementation (30 and 150 mg/kg/d) for 3 weeks. FDB significantly reduces metabolic byproduct accumulation, liver and intestinal damage, and enhances glycogen storage and antioxidant capacity in intense exercise mice. Moreover, FDB restructures the small intestinal microbiota by increasing the abundance of probiotics and butyric acid producing bacteria and decreasing the abundance of pathogenic bacteria. FDB also regulates the levels of metabolites involved in TCA cycle and amino acid metabolism in urine and small intestine content. Correlation analysis shows that FDB-modulated microbiota is highly associated with its antifatigue effect. FDB may ameliorate fatigue and intestinal injury through targeting small intestinal microbiota.

Polymethoxyflavones in orange peel extract prevent skeletal muscle damage induced by eccentric exercise in rats.

Polymethoxyflavones (PMFs) contained in the peel of citrus fruits have anti-inflammatory, anticancer, and antidepressant effects. However, their effects on skeletal muscle are unknown. We investigated whether PMFs could prevent skeletal muscle damage induced by eccentric exercise in rats. Downhill running for 90 min increased the levels of the inflammatory cytokines, monocyte chemotactic protein-1 (MCP-1), and interleukin-1ß (IL-1ß) in skeletal muscles, especially in vastus lateralis, and the plasma creatine kinase levels. These increases were attenuated by a single oral administration of orange peel extract (OPE) 30 min before downhill running. A mixture of nobiletin, sinensetin, 3,5,6,7,8,3',4'-heptamethoxyflavone, and tangeretin, which are the major PMFs of OPE, also showed similar effects on muscle damage. These results suggest that OPE has a protective effect against eccentric exercise-induced skeletal muscle damage, and that the effects may be attributed to the 4 major PMFs.

[Follow-up study in German Hunting Terrier dogs with exercise induced metabolic myopathy]. / Verlaufsuntersuchungen bei Deutschen Jagdterriern mit belastungsabhängiger metabolischer Myopathie.

OBJECTIVE: Exercise induced metabolic myopathy in German Hunting Terrier dogs is an autosomal-recessively inherited disorder, caused by a nonsense variant of the gene encoding for the very long-chain acyl-CoA-dehydrogenase (VLCAD) enzyme. Clinical signs include exercise- induced fatigue, muscle pain and weakness. In the present study, the long-term course of this disease was investigated over a period of 1 year in 9 affected German Hunting Terriers. The dogs were treated symptomatically with oral L-carnitine, coenzyme Q10 and a special diet characterized by a low content of long-chain fatty acids and a high proportion of carbohydrates. MATERIAL AND METHODS: In 9 affected dogs, the phenotype as well as clinical, laboratory parameters, and histopathological findings are described (time point 1) and compared to follow-up examinations 1 year later (time point 2). At both time points clinical and neurological examinations, complete blood cell count, clinical chemistry profile and the concentration of brain natriuretic peptide (NT-proBNP) were investigated. RESULTS: In the follow-up examinations, the same post-exercise clinical signs were present as in the initial presentation of the homozygous dogs. Dark-brownish discoloration of the urine, weakness, myalgia as well as stiff and tetraparetic gait were apparant. All hematological values and the concentration of NT-proBNP were within the relevant reference ranges. Plasma CK and ALT activities were compared between the first presentation and the follow- up examination and no significant differences were detected (pCK = 0.31, pALT = 0.64). Signs of myopathy remained unchanged throughout the examination period. CONCLUSION AND CLINICAL RELEVANCE: Oral supplementation with L-carnitine, coenzyme Q10 and the special dietary management did not result in any improvement of clinical signs or laboratory parameters. No progression of the disease was observed. The prognosis for affected dogs remains cautious as long-term observations of affected dogs over several years are lacking. Our findings provide further important information on inherited disorders of mitochondrial ß-oxidation in dogs, especially focused on the exercise induced metabolic myopathy in the German Hunting Terrier. This may provide new insights for novel treatment modalities in conjuntion with the development of improved breeding guidelines.

Silibinin Alleviates the Learning and Memory Defects in Overtrained Rats Accompanying Reduced Neuronal Apoptosis and Senescence.

Excessive physical exercise (overtraining; OT) increases oxidative stress and induces damage in multiple organs including the brain, especially the hippocampus that plays an important role in learning and memory. Silibinin, a natural flavonoid derived from milk thistle of Silybum marianum, has been reported to exert neuroprotective effect. In this study, rats were subjected to overtraining exercise, and the protective effects of silibinin were investigated in these models. Morris water maze and novel object recognition tests showed that silibinin significantly attenuated memory defects in overtrained rats. At the same time, the results of Nissl, TUNEL and SA-ß-gal staining showed that silibinin reversed neuronal loss caused by apoptosis, and delayed cell senescence of the hippocampus in the overtrained rats, respectively. In addition, silibinin decreased malondialdehyde (MDA) levels which is associated with reactive oxygen species (ROS) generation. Silibinin prevented impairment of learning and memory caused by excessive physical exercise in rats, accompanied by reduced apoptosis and senescence in hippocampus cells.

Protective effects of photobiomodulation against resistance exercise-induced muscle damage and inflammation in rats.

We investigated whether low-level laser therapy (LLLT) prior to or post resistance exercise could attenuate muscle damage and inflammation. Female Wistar rats were assigned to non-LLLT or LLLT groups. An 830-nm DMC Laser Photon III was used to irradiate their hind legs with 2J, 4J, and 8J doses. Irradiations were performed prior to or post (4J) resistance exercise bouts. Resistance exercise consisted of four maximum load climbs. The load work during a resistance exercise bout was similar between Control (non-LLLT, 225 ± 10 g), 2J (215 ± 8 g), 4J (210 ± 9 g), and 8J (226 ± 9 g) groups. Prior LLLT did not induce climbing performance improvement, but exposure to 4J irradiation resulted in lower blood lactate levels post-exercise. The 4J dose decreased creatine kinase and lactic dehydrogenase levels post-exercise regardless of the time of application. Moreover, 4-J irradiation exposure significantly attenuated tumor necrosis factor alpha, interleukin-6, interleukin-1ß, cytokine-induced neutrophil chemoattractant-1, and monocyte chemoattractant protein-1. There was minor macrophage muscle infiltration in 4J-exposed rats. These data indicate that LLLT prior to or post resistance exercise can reduce muscle damage and inflammation, resulting in muscle recovery improvement. We attempted to determine an ideal LLLT dose for suitable results, wherein 4J irradiation exposure showed a significant protective role.

Metabolomics analysis of serum reveals the effect of Danggui Buxue Tang on fatigued mice induced by exhausting physical exercise.

Danggui Buxue Tang (DBT), believed to invigorate 'Qi' (vital energy) and nourish 'Blood' (body circulation), is a traditional Chinese medicine formula. In this study, a metabolomics approach with gas chromatography coupled to mass spectrometry combined with pattern recognition was adopted to investigate the underlying mechanism of the antifatigue effect of DBT on fatigue of mice induced by weight-loaded forced swimming. Fourteen endogenous metabolites, up-regulated or down-regulated, were identified in the model mice by analysis tools of partial least-squares discriminant analysis (PLS-DA) and XCMS online software. Furthermore, the metabolites were reversed by DBT treatment, offering evidence for the antifatigue effect. In addition, intervention of DBT changed the levels of biochemical parameters. DBT showed obvious efficacy on the fatigued mice possibly by regulating the pathways of phenylalanine, tyrosine and tryptophan metabolism, glycine, serine, and threonine metabolism, glyoxylate and dicarboxylate metabolism, pyruvate metabolism, and TCA cycle. This study demonstrated that DBT has a good antifatigue effect and that metabolomics is a powerful means to gain insights into the therapeutic effect of traditional Chinese medicine formulas.

Capillarisin attenuates exercise-induced muscle damage through MAPK and NF-κB signaling.

BACKGROUND: Intense exercise has the potential to increase oxidative stress and cause muscle damage. Mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB) are two major regulators of gene transcription in response to oxidative stress in the skeletal muscle. Pure capillarisin (CAP) isolated from Artemisia capillaris Thunberg is known to have antioxidant and anti-inflammatory effects. HYPOTHESIS/PURPOSE: We hypothesized CAP to exert antioxidant activity against exercise-induced oxidative stress and suppress acute inflammatory response. We aimed to investigate skeletal muscle recovery after intense exercise with or without CAP administration. STUDY DESIGN: Eccentric exercise was conducted to induce muscle damage (C57BL6 mice, 13m/min for 60min downhill running). Mice were divided into four groups (n=6): the rested control, exercised, and exercised with CAP treatments (20mg/kg and 80mg/kg, ip injection 24h prior to exercise) groups. METHOD: After the intense exercise, mice were sacrificed immediately, and after 24h the gastrocnemius muscles and blood plasma were collected for further study. The DCFH-DA and TBARS assays were conducted for anti-oxidative capacity. Muscle damage markers, creatinine phosphate kinase (CPK) and lactate dehydrogenase (LDH) were investigated at plasma level. Muscle data were examined with H&E staining and microscopy. MAPK and NF-κB pathway, chemokine and cytokine productions were confirmed by western blotting and RT-PCR. RESULTS: From DCFH-DA and TBARS assays, exercise increased the level of ROS production, but these changes were suppressed by CAP treatment. Exercise induced muscle damage by raising the levels of soluble muscle enzymes, such as CPK and LDH. However, this result was improved in CAP-treated groups at plasma level. Exercise activated MAPK (ERK 1/2 and JNK but not p38) and NF-κB (nuclear p50 and p65, and cytosolic p-IκBα) subunits at protein level but CAP attenuated these increase in a dose dependent manner. At the mRNA level, the chemokines CINC-1 and MCP-1, and cytokine IL-6 in gastrocnemius muscle were increased by exercise, whereas CAP suppressed these increase. CONCLUSION: Overall, our results indicate that CAP, as a single compound, can attenuate muscle damage by exerting antioxidant and anti-inflammatory effects. Thus, CAP is a potential candidate for the muscle protective agent in the future.

Vitamin A Oral Supplementation Induces Oxidative Stress and Suppresses IL-10 and HSP70 in Skeletal Muscle of Trained Rats.

Exercise training intensity is the major variant that influences the relationship between exercise, redox balance, and immune response. Supplement intake is a common practice for oxidative stress prevention; the effects of vitamin A (VA) on exercise training are not yet described, even though this molecule exhibits antioxidant properties. We investigated the role of VA supplementation on redox and immune responses of adult Wistar rats subjected to swimming training. Animals were divided into four groups: sedentary, sedentary + VA, exercise training, and exercise training + VA. Over eight weeks, animals were submitted to intense swimming 5 times/week and a VA daily intake of 450 retinol equivalents/day. VA impaired the total serum antioxidant capacity acquired by exercise, with no change in interleukin-1ß and tumor necrosis factor-α levels. In skeletal muscle, VA caused lipid peroxidation and protein damage without differences in antioxidant enzyme activities; however, Western blot analysis showed that expression of superoxide dismutase-1 was downregulated, and upregulation of superoxide dismutase-2 induced by exercise was blunted by VA. Furthermore, VA supplementation decreased anti-inflammatory interleukin-10 and heat shock protein 70 expression, important factors for positive exercise adaptations and tissue damage prevention. Our data showed that VA supplementation did not confer any antioxidative and/or protective effects, attenuating exercise-acquired benefits in the skeletal muscle.

Excessive training is associated with endoplasmic reticulum stress but not apoptosis in the hypothalamus of mice.

Downhill running-based overtraining model increases the hypothalamic levels of IL-1ß, TNF-α, SOCS3, and pSAPK-JNK. The aim of the present study was to verify the effects of 3 overtraining protocols on the levels of BiP, pIRE-1 (Ser724), pPERK (Thr981), pelF2α (Ser52), ATF-6, GRP-94, caspase 4, caspase 12, pAKT (Ser473), pmTOR (Ser2448), and pAMPK (Thr172) proteins in the mouse hypothalamus. The mice were randomized into the control, overtrained by downhill running (OTR/down), overtrained by uphill running (OTR/up), and overtrained by running without inclination (OTR) groups. After the overtraining protocols (i.e., at the end of week 8), hypothalamus was removed and used for immunoblotting. The OTR/down group exhibited increased levels of all of the analyzed endoplasmic reticulum stress markers in the hypothalamus at the end of week 8. The OTR/up and OTR groups exhibited increased levels of BiP, pIRE-1 (Ser724), and pPERK (Thr981) in the hypothalamus at the end of week 8. There were no significant differences in the levels of caspase 4, caspase 12, pAKT (Ser473), pmTOR (Ser2448), and pAMPK (Thr172) between the experimental groups at the end of week 8. In conclusion, the 3 overtraining protocols increased the endoplasmic reticulum stress at the end of week 8.

Neoagarotetraose protects mice against intense exercise-induced fatigue damage by modulating gut microbial composition and function.

SCOPE: Exhaustive exercise stress has emerged as an important health issue, and gastrointestinal problems are a common concern during intense exercise. In this study, we investigated the potential antifatigue effects of neoagarotetraose (NAT) in mice under intense exercise stress. MATERIALS AND METHODS: Exhaustive exercise stress significantly weakened several physiological and physical parameters of the mice, including decreased food intake, reduced body weight, and impaired integrity of the intestinal epithelial barrier. Our data showed that a 16-day NAT treatment resulted in a profound change in microbiome composition, which subsequently led to widespread shifts in the functional potential of the gut microbiome. Furthermore, NAT administration significantly increased the fecal concentration of total short-chain fatty acids (p < 0.01). CONCLUSION: Together, our findings suggest that NAT may protect mice against intense exercise-induced fatigue and provide insights into the mechanisms of NAT as a potential prebiotic.

[The protective effects of Haematococcus pluvialis on the exercise-induced myocardial injury in rat].

OBJECTIVE: To study the protective effects of Haematococcus pluvialis (H. pluvialis) on myocardial injury of rats induced by endurance and intensive exercise. METHODS: The model was based on intensive endurance training. Sixty-five male aged 42 days Wistar rats were randomly divided into 5 groups:control group (C group), general training group (M group), low dose H. pluvialis + training group (HM I group), middle dose H. Pluvialis + training group (HM Ⅱ group), high dose H. pluvialis + training group (HM Ⅲ group). Each group included 12 rats, and the rats were assigned to go on a 42-day swimming training regime. Professional gavage were taken daily. The rats in HM I, HM Ⅱ and HM Ⅲ group were treated with H. pluvialis at the doses of 0.067,0.133 and 0.4 g/kg by ig at 5 ml/kg and the normal saline were given to other groups. After a 42-day swimming training regime, myocardial injury markers such as serum alanine aminotransferase (ALT), myocardial superoxide dismutase(SOD) and malondialdehyde (MDA) were detected, the biochemical indexes such as serum and myocardial endothelin (ET) and calcitonin gene related peptide (CGRP)were detected. RESULTS: Serum ALT, lactate dehydrogenase(LDH), creatine kinase(CK), a-hydroxybutyrate dehydrogenase(a-HBDH), ET, myocardial MDA and ET in M group were significantly higher than those in C group (P<0.05 or P<0.01). The myocardial SOD activity and the myocardial and serum CGRP in M group were significantly lower than those in C group(P<0.05 or P<0.01). The contents of serum ALT, LDH and CK in HM groups were lower than those in the M group but there was no significant difference between the two groups. Compared with M group, H. pluvialis could decrease the levels of serum a-HBDH, ET and myocardial ET in a dose-dependent manner (P<0.05 or P<0.01). The above mentioned three parameters in HM Ⅲ group were lower than those in HM I group (P<0.05). H. pluvialis could decrease the levels of myocardial MDA and increase the levels of myocardial SOD activity and serum or myocardial CGRP in a dose-dependent manner (P<0.05 or P<0.01). CONCLUSIONS: The different doses of H.pluvialis can effectively reduce the free radicals caused by endurance and intensive training and enhance the immune function. Meanwhile H.pluvialis is able to guarantee the relative balance in ET an CGRP`s concentration. Therefore, the myocardial lipid peroxidation and myocardial injury are encumbered. Additionaly, high dose of H. pluvialis is proven to be the most effective.

Acute resistance exercise-induced IGF1 expression and subsequent GLUT4 translocation.

Acute aerobic exercise (AE) is a major physiological stimulus for skeletal muscle glucose uptake through activation of 5' AMP-activated protein kinase (AMPK). However, the regulation of glucose uptake by acute resistance exercise (RE) remains unclear. To investigate the intracellular regulation of glucose uptake after acute RE versus acute AE, male Sprague-Dawley rats were divided into three groups: RE, AE, or nonexercise control. After fasting for 12 h overnight, the right gastrocnemius muscle in the RE group was exercised at maximum isometric contraction via percutaneous electrical stimulation (3 × 10 sec, 5 sets). The AE group ran on a treadmill (25 m/min, 60 min). Muscle samples were taken 0, 1, and 3 h after completion of the exercises. AMPK, Ca(2+)/calmodulin-dependent protein kinase II, and TBC1D1 phosphorylation were increased immediately after both forms of exercise and returned to baseline levels by 3 h. Muscle IGF1 expression was increased by RE but not AE, and maintained until 3 h after RE Additionally, Akt and AS160 phosphorylation were sustained for 3 h after RE, whereas they returned to baseline levels by 3 h after AE Similarly, GLUT4 translocation remained elevated 3 h after RE, although it returned to the baseline level by 3 h after AE Overall, this study showed that AMPK/TBC1D1 and IGF1/Akt/AS160 signaling were enhanced by acute RE, and that GLUT4 translocation after acute RE was more prolonged than after acute AE These results suggest that acute RE-induced increases in intramuscular IGF1 expression might be a distinct regulator of GLUT4 translocation.

The Preventive Effect of Calcium Supplementation on Weak Bones Caused by the Interaction of Exercise and Food Restriction in Young Female Rats During the Period from Acquiring Bone Mass to Maintaining Bone Mass.

Increasing calcium (Ca) intake is important for female athletes with a risk of weak bone caused by inadequate food intake. The aim of the present study was to examine the preventive effect of Ca supplementation on low bone strength in young female athletes with inadequate food intake, using the rats as an experimental model. Seven-week-old female Sprague-Dawley rats were divided into four groups: the sedentary and ad libitum feeding group (SED), voluntary running exercise and ad libitum feeding group (EX), voluntary running exercise and 30% food restriction group (EX-FR), and a voluntary running exercise, 30% food-restricted and high-Ca diet group (EX-FR+Ca). To Ca supplementation, we used 1.2% Ca diet as "high-Ca diet" that contains two-fold Ca of normal Ca diet. The experiment lasted for 12 weeks. As a result, the energy availability, internal organ weight, bone strength, bone mineral density, and Ca absorption in the EX-FR group were significantly lower than those in the EX group. The bone strength and Ca absorption in the EX-FR+Ca group were significantly higher than those in the EX-FR group. However, the bone strength in the EX-FR+Ca group did not reach that in the EX group. These results suggested that Ca supplementation had a positive effect on bone strength, but the effect was not sufficient to prevent lower bone strength caused by food restriction in young female athletes.

The Impaired Function of Macrophages Induced by Strenuous Exercise Could Not Be Ameliorated by BCAA Supplementation.

The aim of this study was to evaluate the effect of strenuous exercise on the functions of peritoneal macrophages in rats and to test the hypothesis that branched-chain amino acid (BCAA) supplementation will be beneficial to the macrophages of rats from strenuous exercise. Forty male Wistar rats were randomly divided into five groups: (C) Control, E) Exercise, (E1) Exercise with one week to recover, (ES) Exercise + Supplementation and (ES1) Exercise + Supplementation with 1 week to recover. All rats except those of the sedentary control were subjected to four weeks of strenuous exercise. Blood hemoglobin, serum testosterone and BCAA levels were tested. Peritoneal macrophages functions were also determined at the same time. The data showed that hemoglobin, testosterone, BCAA levels, and body weight in group E decreased significantly as compared with that of group C. Meanwhile, phagocytosis capacity (decreased by 17.07%, p = 0.031), reactive oxygen species (ROS) production (decreased by 26%, p = 0.003) and MHC II mRNA (decreased by 22%, p = 0.041) of macrophages decreased in the strenuous exercise group as compared with group C. However, the chemotaxis of macrophages did not change significantly. In addition, BCAA supplementation could slightly increase the serum BCAA levels of rats from strenuous exercise (increased by 6.70%, p > 0.05). Moreover, the body weight, the blood hemoglobin, the serum testosterone and the function of peritoneal macrophages in group ES did not change significantly as compared with group E. These results suggest that long-term intensive exercise impairs the function of macrophages, which is essential for microbicidal capability. This may represent a novel mechanism of immunosuppression induced by strenuous exercise. Moreover, the impaired function of macrophage induced by strenuous exercise could not be ameliorated by BCAA supplementation in the dosing and timing used for this study.

The effect of dry needling and treadmill running on inducing pathological changes in rat Achilles tendon.

Achilles tendinopathy is a common degenerative condition without a definitive treatment. An adequate chronic animal model of Achilles tendinopathy has not yet been developed. The purpose of this study was to evaluate the individual and combined effects of dry needling and treadmill running on the Achilles tendon of rats. Percutaneous dry needling, designed to physically replicate microrupture of collagen fibers in overloaded tendons, was performed on the right Achilles tendon of 80 Sprague-Dawley rats. The rats were randomly divided into two groups: a treadmill group, which included rats that underwent daily uphill treadmill running (n = 40), and a cage group, which included rats that could move freely within their cages (n = 40). At the end of weeks 1 and 4, 20 rats from each group were sacrificed, and bilateral Achilles tendons were collected. The harvested tendons were subjected to mechanical testing and histological analysis. Dry needling induced histological and mechanical changes in the Achilles tendons at week 1, and the changes persisted at week 4. The needled Achilles tendons of the treadmill group tended to show more severe histological and mechanical changes than those of the cage group, although these differences were not statistically significant. Dry needling combined with free cage activity or treadmill running produced tendinopathy-like changes in rat Achilles tendons up to 4 weeks after injury. Dry needling is an easy procedure with a short induction period and a high success rate, suggesting it may have relevance in the design of an Achilles tendinopathy model.

ß-glucan reduces exercise-induced stress through downregulation of c-Fos and c-Jun expression in the brains of exhausted rats.

Immediate-early genes are involved in acute stress responses in the central nervous system. ß-glucan stimulates innate immune defenses, exerts an anti-tumor response and increases resistance to a wide variety of types of infection. To date, the effect of ß-glucan on the expression of immediate-early genes under stressful conditions has not been elucidated. In the present study, the effects of ß-glucan on the expression of the oncogenes c-Fos and c-Jun in the hypothalamus, dentate gyrus and dorsal raphe in rats following exhaustive treadmill running were investigated. Male Sprague Dawley rats were randomly divided into five groups (n=10 in each group) as follows: Control, exercise, exercise and 50 mg/kg ß-glucan treatment, exercise and 100 mg/kg ß-glucan treatment, and exercise and 200 mg/kg ß-glucan treatment. Rats in the ß-glucan­treated groups were administered ß-glucan at the respective dose once per day for seven days. Rats in the exercise groups performed treadmill running once per day for six days. On the seventh day of the experiment, the time to exhaustion in response to treadmill running was determined for the exercise groups. The expression of c-Fos and c-Jun in the hypothalamus, dorsal raphe and hippocampus was enhanced by exhaustive treadmill running. Administration of ß-glucan resulted in an increase in the time to exhaustion and the suppression of the exercise-induced increment in c-Fos and c-Jun expression. In conclusion, ß-glucan may exert an alleviating effect on exercise-induced stress through the suppression of c-Fos and c-Jun expression in the brains of exhausted rats.

Oxidative metabolism and muscle biochemical profile of polo horses supplemented with an ADE vitamin complex / Metabolismo oxidativo e perfil bioquímico muscular de cavalos de pólo suplementados com complexo vitamínico ADE

Horses used for the game of polo experience abrupt and frequent changes in exercise intensity. To meet this variable energy demand, the horses use both aerobic and anaerobic pathways in varying proportions and intensities. In this context, there must be a balance between the formation of reactive oxygen species (ROS) and the action of antioxidants to prevent oxidative stress and its consequences. The effect of supplementation with an ADE vitamin complex on oxidative metabolism was evaluated in 18 crossbred horses randomly divided between a treated group (TG) and a control group (CG). The TG animals received the ADE vitamin complex (1mL/50 kg of body weight) by deep intramuscular injection at 30 and 15 days before the game. The CG horses received 10ml of saline by the same administration route and schedule. During the polo match, the animals played for a total of 7.5 min. Blood samples were collected on the same days as the treatments were administered, and immediately before and at 15, 90 and 180 minutes after the game. The concentrations of creatine phosphokinase (CK), lactate dehydrogenase (LDH), lactate, glucose, aspartate aminotransferase (AST), glutathione (GSH), superoxide dismutase (SOD) and malondialdehyde (MDA) were measured in the blood samples. After the game, the TG demonstrated higher levels of AST, lactate and glucose than the CG, suggesting more efficient energy use by the treated animals. The higher GSH and lower lactate levels in the TG before the game suggest the presence of a greater antioxidant supply in the treated animals. The maintenance of the MDA levels indicates that neither of the groups exhibited oxidative stress.

O jogo de pólo se caracteriza por mudanças abruptas e frequentes na intensidade do exercício dos cavalos. Para satisfazer esta demanda inconstante de energia, os animais utilizam as vias aeróbia e anaeróbia em proporções e intensidade variáveis. Neste contexto deve haver equilíbrio entre a formação das espécies reativas de oxigênio (EROs) e a ação das substâncias antioxidantes a fim de evitar o estresse oxidativo e suas consequências. Avaliou-se o efeito da suplementação com vitaminas ADE no metabolismo oxidativo destes animais. Para tanto, 18 equinos mestiços foram distribuídos aleatoriamente em dois grupos: tratado e controle (GT) e controle (GC).Os animais do GT receberam complexo vitamínico ADE (1 mL/50 kg de peso vivo) pela via intramuscular profunda aos 30 e 15 dias antes do jogo. Os cavalos do GC receberam, pela mesma via de administração e nos mesmos momentos, 10mL de solução fisiológica. Os animais jogaram um tempo de 7,5min. Foram coletadas amostras de sangue nos mesmos dias de tratamento e imediatamente antes e aos 15, 90 e 180 minutos após o jogo. Foram determinadas as concentrações sanguíneas de CK, LDH, lactato, glicose, AST, GSH, SOD e MDA. Após o jogo o GT apresentou maiores valores para AST, lactato e glicemia que o GC, sugerindo melhor aproveitamento energético dos animais tratados. Os valores maiores de GSH e menores de lactato no GT antes da prova sugerem maior aporte antioxidante nos animais tratados. A manutenção dos teores de MDA indica que nenhum dos grupos entrou em estresse oxidativo.