Effect of endurance training on the expression profile of circRNA-lncRNA-miRNA-mRNA in myocardial tissues of mice after exhaustive exercise

Objective:To clarify the effect of endurance training on the expression profile of circRNA-lncRNA-miRNA-mRNA in myocardial tissues of mice after exhaustive exercise.Methods:A total of 45 male C57BL/6 mice were randomly divided into control(C),low-strength endurance training(LSET)and high-strength endurance training(HSET)groups(n=15).The mice in the control group were not conducted to platform training.The mice in the LSET and HSET groups were conducted to platform training at 30%and 60%of exhaustive exercise once a day for 5 days a week,respectively.The exhaustion exercise was performed after 5 weeks of platform training.Total RNA was extracted from myocardial tissues,and the expression profile of circRNA-lncRNA-miRNA-mRNA in myocardial tissues was analyzed using Illimina transcriptome sequencing.Results:The distance and time of exhaustive exercise were longer in the LSET and HSET groups than in the control group,and the distance and time of exhaustive exercise were longer in the HSET group than in the LSET group(P<0.05).A total of 54 differentially expressed circRNAs(28 down-regulated and 26 up-regulated),7 differentially expressed lncRNAs(all down-regulated),3 differentially expressed miRNAs(1 down-regulated and 2 up-regulated)and 99 differentially expressed mRNAs(81 down-regulated and 18 up-regulated)were identified by transcriptome sequencing(P<0.05).Interaction network analysis revealed that ENSMUSG00000113041,MSTRG.79740,mmu-miR-374c-5p,18 down-regulated mRNAs and 3 up-regulated mRNAs formed a regulatory network.GO functional analysis revealed that the differentially expressed mRNAs were mainly enriched in primary metabolic processes and macromolecular synthesis and metabolic processes.KEGG pathway analysis revealed that the differentially expressed mRNAs were mainly enriched in complement and coagulation cascade pathways,estrogen signaling pathway and glucagon signaling pathway.Conclusion:Endurance training could alter the expression profile of circRNA-lncRNA-miRNA-mRNA in myocardial tissues of mice after exhaustive exercise,and these differentially expressed RNAs form a regulatory network that affects cardiomyocyte synthesis and metabolism and thus participates in the regulation of myocardial injury.

Hippocampal ultrastructural changes and apoptotic cell death in rats following endurance training and acute exhaustive exercise

BACKGROUND： Exhaustive exercise can lead to apoptosis of skeletal muscle cells and myocardial cells as a result of pathological changes in the corresponding cellular ultrastructure. It is hypothesized that such changes could also occur in neurons. OBJECTIVE： To observe brain cell apoptosis and ultrastructural changes in hippocampal neurons in rats following endurance training and acute exhaustive exercise. DESIGN, TIME AND SETTING： A randomized, controlled, morphological analysis was performed at the Medical Laboratory Center of Zhengzhou University between July and November 2007. MATERIALS： Forty male, 8-week-old, Sprague Dawley rats were included in this study. METHODS： Endurance training consisted of treadmill running once a day, 6 days a week, for 4. weeks. For acute exhaustive exercise, graded treadmill running was conducted. Rats were exposed to exercise at an increasing speed （10 m/min, increasing to 20 and 36 m/min for moderate- and high-intensity exhaustive exercise, respectively, and then was continued until exhaustion）. A total of 40 rats were evenly distributed into the following 4. groups： Group A rats were not exercised; Group B rats were not trained but sacrificed 24 hours after acute exhaustive treadmill running exercise; Group C-rats were subjected to endurance training and sacrificed immediately after acute exhaustive treadmill running exercise; Group D rats were subjected to endurance training and sacrificed 24 hours after acute exhaustive treadmill running exercise. MAIN OUTCOME MEASURES： Apoptotic cell death was detected by the TUNEL method and hippocampal neuronal ultrastructural change was observed through using transmission electron microscopy. RESULTS： All 40 rats were included in the final analysis. Subsequent to exhaustive exercise, rat cerebral cortex and hippocampal neurons appeared contracted and degenerated. In addition, high amount of lipofuscin was visible in the hippocampal region, Necrotic neurons encased by glial cells appeared in the cerebral cortex and hippocampus. Glial cells exhibited different degrees of swelling. Subsequent to exhaustive exercise, brain cell apoptosis rate significantly increased, and reached over 30% in some regions, compared with group A （P 〈 0.05）. No significant difference in apoptosis rate existed between groups B, C, and D （P 〈 0.05）. CONCLUSION： Endurance training and acute exhaustive exercise cause, to some degree, injuries to glial cells, resulting in apoptosis of numerous brain cells. Subsequent to exhaustive exercise, high amounts of lipofuscin appear in the hippocampus, indicating that exhaustive exercise possibly contributes to neural cell aging or dysmetabolism.

Effect of moxibustion at Shenque （CV 8） on free radical metabolism in rat＇s hippocampus after different degrees of exhaustive exercise

Objective： To investigate the effect of moxibustion at Shenque （CV 8） on free radical metabolism in rat＇s hippocampus after different degrees of exhaustive exercise. Methods： A total of 72 male Sprague-Dawley （SD） rats were randomly divided into a normal group （n=8）, a model group （n=32） and a moxibustion group （n=32）. According to the times of modeling or treatment, the model group was further randomly divided into different subgroups of a 1-time model subgroup, a 4-time model subgroup, a 7-time model subgroup and a 10-time model subgroup （n=8）; the moxibustion group was also further randomly divided into different subgroups of a 1-time moxibustion subgroup, a 4-time moxibustion subgroup, a 7-time moxibustion subgroup and a 10-time moxibustion subgroup （n=8）. Rats in both model and moxibustion subgroups were subjected to establishing the swimming exhaustive model. Rats in each moxibustion subgroup received mild moxibustion at Shenque （CV 8） for 15 min immediately after modeling, once every other day. The concentration of malic dialdehyde （MDA）, as well as the activities of superoxide dismutase （SOD）, glutathione peroxidase （GSH-Px） and total antioxidant capacity （T-AOC） in rat＇s hippocampus in each group were detected 24 h after the exhaustive exercise. Results： Compared with the 1-time model subgroup, the exhaustive swimming time of rats was significantly prolonged in the 4-time model subgroup （P〈0.01）, while it was significantly shortened in the 7-time and 10-time model subgroups （both P〈0.01）. Compared with the matched model subgroup, the exhaustive swimming time of rats in the 7-time and 10-time moxibustion subgroups was significantly prolonged （both P〈0.01）. Compared with the normal group, the MDA concentration was increased significantly （P〈0.01）, and the activities stress response of SOD and T-AOC were increased in the 1-time model subgroup （both P〈0.05）; the MDA concentration was increased （all P〈0.01）, and the activities of SOD, GSH-Px and T-AOC were decreased differently （P〈0.05 or P〈0.01） in the 4-time, 7-time and 10-time model subgroups. Compared with the matched model subgroup, the concentration of MDA was significantly reduced （P〈0.05 or P〈0.01）, and the activities of SOD, GSH-Px and T-AOC were significantly increased in the 4-time, 7-time and 10-time moxibustion subgroups （all P〈0.01）. Conclusion： Moxibustion at Shenque （CV 8） can improve the fatigue status of the body after long-term exhaustive exercise by regulating free radical metabolism in rat＇s hippocampus. To some extent, this provides an experimental basis for moxibustion at Shenque （CV 8） against exercise-induced fatigue.

Effect of moxibustion at Shenque (CV8) on immune system in rats with different degrees of exhaustive exercise

Objective: To investigate the effect of moxibustion at Shenque (CV8) on the immune system in rats with different levels of exhaustive exercise. Methods: Fifty-six male Sprague-Dawley (SD) rats were randomly divided into a blank group (n=8), an exhaustive group (n=24), and a moxibustion group (n=24). The exhaustive group was randomly divided into a 1-time exhaustive group, a 4-time exhaustive group and a 7-time exhaustive group, with 8 rats in each group. According to the treatment time, the moxibustion group was randomly divided into a 1-time moxibustion group, a 4-time moxibustion group and a 7-time moxibustion group, with 8 rats in each group. Rats in the exhaustive groups and the moxibustion groups were subjected to replicating the exhaustive swimming models. Rats in each moxibustion group received mild moxibustion for 15 min immediately after the exhaustive modeling, once every other day. Twenty-four hours after the corresponding exhaustive exercise, the rats in each group were tested for the levels of serum immunoglobulin (Ig) G, IgA, IgM and acid phosphatase (ACP), and the morphological changes of spleen tissues were observed. The level of IgA was detected by immunoturbidimetric assay, and the levels of IgG, IgM and ACP were detected by en zyme-linked imm uno sorb ent assay (ELISA). Results: Compared with the 1-time exhaustive group, swimming time of rats in the 4-time exhaustive group was significantly proIonged (P<0.01), and swimming time of rats in the 7-time exhaustive group was significantly shortened (P<0.01). Compared with the 7-time exhaustive group, exhaustive swimming time of rats in the 7-time moxibustion group was significantly proIonged (P<0.01). Compared with the blank group, the IgG level in the 1-time exhaustive group was significantly decreased (PvO.Ol), and the levels of IgG, IgA and IgM in the 4-time exhaustive group and the 7-time exhaustive group were all sign ifica ntly decreased (P<0.05 or PvO.Ol), while the ACP level was in creased sign ifica ntly (both P<0.01). Microscopically, the number of splenic corpuscles in the 1-time exhaustive group was reduced;the center of some splenic corpuscles in the 4-time exhaustive group was damaged;the number of splenic corpuscles in the 7-time exhaustive group was reduced, and there was no obvious germinal center. Compared with the 4-time exhaustive group, the IgA level in the 4-time moxibusti on group was sign ifica ntly in creased (P<0.01), and the ACP level was sign ifica ntly decreased (P<0.01). Compared with the 7-time exhaustive group, the levels of IgG, IgA and IgM in the 7-time moxibustion group were sign ifica ntly in creased (all PvO.Ol), and the ACP level was sign ifica ntly decreased (P<0.01). Microscopically, the nu mber of splenic corpuscles in the 1-time moxibustion group was reduced;the center of some splenic corpuscles in the 4-time moxibustion group was damaged together with hyperplasia of some splenic corpuscles;blast cells were proliferated in the center of some splenic corpuscles in the 7-time moxibustion group. Conclusion: Moxibustion at Shenque (CV 8) can improve the levels of IgG, IgA and IgM, reduce the ACP level, repair damaged spleen tissues, and enhance the immunity of the body to some extent in the Iong-term fatigue rats.

Exhaustive Exercise Does Not Affect Humoral Immunity and Protection after Rabies Vaccination in a Mouse Model

Rabies is one of the most dangerous and widespread zoonosis and is characterized by severe neurological signs and a high case-mortality rate of nearly 100%. Vaccination is the most effective way to prevent rabies in humans and animals. In this study, the relationship between exhaustive exercise and the humoral immune response after immunization with inactivated rabies vaccine was investigated in a mouse model with one-time exhaustive exercise. It was found that compared with the mice with no exercise after vaccination, no significant differences were found in those with exhaustive exercise after vaccination on body-weight changes, virus-neutralizing antibody(VNA) titers, antibody subtypes and survivor ratio after lethal rabies virus(RABV) challenge. This study indicated that exhaustive exercise does not reduce the effects of the rabies inactivated vaccine.

A Yang-invigorating compound mixture alters neurotransmitters in rat telencephalon after exercise-induced fatigue

The aim of this study was to observe the changes in monoamine and amino acid neurotransmitters in the telencephalon of rats at four functional states after exhaustive exercise and treatment with a Yang-invigorating compound recipe.The main components of this Chinese traditional medicine preparation included Radix Ginseng,Rhizoma Chuanxiong,Fructus Schisandrae,Cortex Cinnamomi,Cornu Cervi Pantotrichum,Radix Morindae Officinalis,and Gecko.This experiment showed that dopamine（DA）,5-hydroxyindole acetic acid（5-HIAA）,and γ-aminobutyric acid levels noticeably decreased,while DA/5-hydroxytryptamine（5-HT） increased.Furthermore,glutamate（Glu） and Glu/γ-aminobutyric acid significantly increased after 1 hour of exercise in rats in the exercise ＋ medication group.The 5-HT and 5-HT/5-HIAA levels noticeably decreased,and DA/5-HT and Glu levels showed a robust and significant increase immediately after exhaustive exercise.The 5-HT,5-HT/5-HIAA levels sharply decreased,while DA/5-HT,Glu and γ-aminobutyric acid levels increased at 12 hours after exhaustion recovery.The results prove that Chinese herbal formula for strengthening Yang can induce changes in neurotransmitters in the telencephalon of rats after exhaustive exercise during the recovery process,and further improve central nervous system function.

Total soy saponins improve the antioxidant capacity of the myocardium and exercise ability in exhausted rats

Purpose：The aim of the present study was to investigate the impact of total soy saponins（TS） on the myocardial antioxidant capacity in rats exercised to exhaustion.Methods：The one-time exhausted treadmill model was used.All rats were divided into 4 groups：the control group,the TS group,the exhausted group,and the TS exhausted group.The TS and TS exhausted groups were fed TS at a dosage of 20 mg/kg body weight,once a day,for 2 weeks.The exhausted group was given a placebo,and the control group was not given any treatment.The treadmill speed was set at 30 m/min,and the rats（exhausted and TS exhausted groups） were trained at this speed until exhausted.The rats were decapitated and anatomized immediately after exhausted.A 10% homogenate of the myocardial tissue was prepared.Results：TS significant y increased the exercise time by 20.62%（p〈0.05）.As compared with the control group,the enzyme activities for catalase（CAT）,glutathione peroxidase（GSH-Px）,and glutathione reductase（GR） were significant y enhanced in the TS group（p〈0.01）;GR and GSH-Px activity was significant y enhanced in the TS exhausted group（p〈0.01）;malondialdehyde（MDA） levels were significant y decreased in the TS exhausted group（p〈0.05）.As compared with the exhausted group,the GSH-Px activity was significant y enhanced in the TS exhausted group（p〈0.01）;CAT,GSH-Px,and GR activities were significant y enhanced in the TS group（p〈0.01）.As compared with the TS group,the CAT and GR activity in the TS exhausted group was significant y decreased（p〈0.01）.Conclusion：TS can improve the exercised rats＇ antioxidant activity in their cardiac muscle to varying degrees,decrease MDA and serum AST and LDH levels,increase the exercise time,and delay the occurrence of sports fatigue.

Effect of moxibustion at Shénquè(神阙 CV 8) on anti-exercise-induced fatigue in exhaustive rats in varying degrees

Objective To explore the effect of moxibustion at Shenque （神阙 CV 8） on the anti-exercise-induced fatigue in rats after exhaustive exercise in varying degrees. Methods Seventy-two SD rats were randomly divided into 3 groups according to the random number table method, including blank group, model group and moxibustion group. The model group and moxibustion group were divided into 4 subgroups respectively, that was 1 time, 4 times, 7 times and 10 times subgroup. There were 9 groups with 8 rats in each group. Except blank group, all the rats were established into exhaustive models through swimming. Mild moxibustion at CV 8 was carried out for 15 min in the rats in moxibustion group after modeling for once every other day. The concentration of serum glucose （GLU）, malonaldehyde （MDA） and blood urea nitrogen （BUN） as well as the activity of aspartate transaminase （AST）, alanine transaminase （ALT） and lactic dehydrogenase （LDH） were detected 24h after the exhaustive exercise by adopting full-automatic analyzer. Results The exhaustive time of rats were long at first but shorter later. The exhaustive time of rats in the model group （4 times） were obviously longer than that in the model group （1 time） （P〈0.01）, the exhaustive time of rats in the model group （7 times） and model group （10 times） were obviously shorter than that in the model group （1 time） （P〈0.01）, and the exhaustive time of rats in the moxibustion group （7 times） and moxibustion group （10 times） were obviously longer than that in the model group with the same number of times （P〈0.01）, the serum GLU level of rats in the model group （7 times） and model group （10 times） increased when compared with the blank group （P〈0.01）, and the serum MDA and BNU levels as well as the activity of AST, ALT and LDH of rats in the model group （4 times）, model group （7 times） and model group （10 times） increased when compared with the blank group （P〈0.05 or P〈0.01）, the serum GLU, MDA and BNU levels as well as the activity of AST and ALT of rats in the moxibustion group （7 times） and moxibustion group （10 times） reduced when compared with the model group with the same number of times （P〈0.05 or P〈0.01）, and the serum LDH activity of rats in the moxibustion group （4 times）, moxibustion group （7 times） and moxibustion group （10 times） reduced when compared with the model group with the same number of times （P〈0.05 or P〈0.01）. Conclusion Moxibustion at CV 8 can reduce the serum MDA and BNU levels as well as the activity of AST, ALT and LDH of organism in a status of long-term fatigue, effectively improve the symptom of long-term fatigue, providing a certain experimental basis for the clinical application of moxibustion at CV 8 in the process of anti-exercise-induced fatigue in the future.

Influence of Intravenous Injection of Hydroxyapatite on Mouse Movement Ability

Lactic acid is usually formed during strenuous exercise, and a large amount of lactic acid and slow anaerobic glycolysis in muscle lead to limitations of movement ability. Hydroxyapatite（HAp） is an alkaline inorganic material with a good biocompatibility. It slowly degrades in vivo and releases trace amounts of calcium ions, reducing cell damage by reacting with polylactic acid and neutralizing local acid environment. Whether HAp can reduce the concentration of lactic acid in vivo and improve movement ability is not yet clear. Here, after eight days of training, 40 mice were randomly divided into four groups： control, distilled water, sodium bicarbonate and HAp group. After one day of rest, the mice were intravenously injected via the lateral tail veins with 1 ml distilled water, sodium bicarbonate and HAp suspension（2.2 mg/ml）, respectively, and subjected to a swimming exhaustive experiment（load 10%）. The swimming time of mice in the water, under water and total time were recorded. The exhaustive exercise mice were immediately subject to abdominal cavity anaesthesia. The concentrations of blood, gastrocnemius and myocardial lactic acid as well as serum LDH activity were detected. We demonstrate that HAp can significantly prolong swimming time and improve serum LDH activity, but does not affect lactic acid concentration. In conclusion, intravenous injection of HAp nanoparticles can significantly improve the exhaustive swimming ability of mice mainly because of the elevated blood LDH activity induced by HAp.

Evaluation of silymarin extract from Silybum marianum in mice: anti-fatigue activity

Silymarin has been used for centuries for its hepatoprotective properties. The specific objective of this study was to evaluate the anti-fatigue properties of silymarin. The silymarin was administered orally at doses of 50, 100, and 200 mg/kg for 4 weeks;the fatigue level and exercise performance were evaluated using exhaustive swimming time and pole-climbing time, as well as levels of plasma lactate, ammonia, glucose, creatine kinase(CK), serum urea nitrogen(SUN), blood lactic acid(BLA), muscle glycogen(MG), and liver glycogen(LG) contents after an intensive swimming session. The results demonstrated that silymarin treatment decreased the BLA and SUN levels while increased the LG and MG levels. In addition, silymarin decreased plasma lactate and ammonia levels and CK activity after swimming test, this is related to the mechanism that increases energy storage(as glycogen) and release(as blood glucose), and decreases plasma levels of lactate, ammonia, and CK. The observation of the skeletal muscle structures of mice also confirmed that skeletal muscles became more damaged in the control group compared with the silymarin-treated mice after prolonged endurance exercise. Therefore, it is reasonable to infer that silymarin may bear potential pharmacological effects in combating fatigue.

Detraining after tumor-bearing accelerates tumor growth while continuous training decreases tumor growth in mice

Objective:Previous studies have shown that exercise suppresses tumor growth.However,the effects of exercise with different intensities and exercise detraining after tumor-bearing on tumor progression remain unclear.The purpose of this study was to investigate the effects of continuous and disrupted free and exhausted swimming training after tumor-bearing on tumor progression in melanoma B16-F10-bearing C57BL/6 mice.Methods:C57BL/6 mice were subjected to free or exhausted swimming exercise training for 4 weeks prior to the injection of melanoma B16-F10 cells.Subsequently,the B16-F10-bearing mice were maintained with training consisting of free or exhausted swimming or without exercise for 2 weeks during the tumor challenge.Results:The tumor weight was increased by 42%and 109%in mice with 4-week exhausted swimming prior to B16-F10 tumor cells inoculation followed by 2-week training cessation compared with the tumor-bearing control(P<.05)and continuous training groups(P<.01).Tumor weights in groups with exercise detraining after tumor cell inoculation tended to be increased,while the proliferation of splenic T lymphocytes tended to be decreased compared with the group that maintained exercise intensity.After 6-weeks continuous free or exhausted swimming training,the tumor weight of mice was decreased and the proliferation of splenic T lymphocytes was increased compared with the tumor-bearing control group.The frequency of natural killer cells in tumors was increased in all exercise training groups of mice.Conclusions:These results suggest that maintaining exercise intensity after tumor-bearing slows tumor growth in mice,possibly because of the enhanced proliferative activity of splenic lymphocytes rather than natural killer cell infiltration.However,detraining after tumor-bearing might accelerate tumor progression because of the reduced proliferation of splenic T lymphocytes.

Experimental study on the effect of moxibustion at Shenque(CV 8) for long-term exercise-induced fatigue

Objective:To investigate the effect of moxibustion at Shenque(CV 8)on fatigue in rats with chronic exercise-induced exhaustion.Methods:Thirty male Sprague-Dawley(SD)rats were randomly divided into a blank group,a model group and a moxibustion group,10 rats in each group.Except rats in the blank group,the remaining rats were subjected to create long-term exhaustion models by repeated swimming.After successful modeling,rats in the moxibustion group received mild moxibustion at Shenque(CV 8)for 15 min,once every other day with a total of 10 times.Rats in the model group and the blank group did not receive moxibustion.At the end of the treatment,the exhausted times,and the body weight of rats before and after the experiment were compared among groups.The levels of blood malondialdehyde(MDA)and urea nitrogen(BUN),as well as the activities of aspartate transarninase(AST),alanine aminotransferase(ALT)and lactate dehydrogenase(LDH)were also measured by the automatic biochemical analyzer,24 h after the exhausting excise.Results:The 10 th swimming time was significantly longer in the moxibustion group than that in the model group(P〈0.01).The increase rate of the body weight was lower in the rats of the moxibustion group than that in the model group before the 7 th and the 10 th exhausting excise(P〈0.05,P〈0.01).The levels of serum MDA and BUN,as well as the activities of AST,ALT and LDH in the model group were higher than those in the blank group(all P〈0.01).The levels of serum MDA and BUN,as well as the activities of AST,ALT and LDH in the moxibustion group were lower than those in the model group(P〈0.01).Conclusion:Moxibustion at Shenque(CV 8)can decrease the serum levels of MDA and BUN,as well as activities of AST,ALT and LDH in the long-term fatigue rats,thus to improve the symptoms of fatigue.

Changes in energy metabolism in the quadriceps femoris after a single bout of acute exhaustive swimming in rats： a 31p-magnetic resonance spectroscopy study

Background Little is known about the value of 31P-magnetic resonance spectroscopy （31P-MRS） in in vivo assessment of exhaustive exercise-induced injury in skeletal muscle.We aimed to evaluate the value of a 31P-MRS study using the quadriceps femoris after a single bout of acute exhaustive swimming in rats,and the correlation between 31P-MRS and histological changes.Methods Sixty male Sprague-Dawley rats were randomly assigned to control,half-exhaustive,and exhaustive exercise groups.31P-MRS of the quadriceps femoris of the right lower limb was performed immediately after swimming exercise to detect Pi,PCr,and β-ATP.The Pi/PCr,Pi/β-ATP,PCr/β-ATP,and PCr/（PCr＋Pi） were calculated and pH measured.Areas under the receiver operating characteristic curve （AUCs） were calculated to evaluate the diagnostic potential of 31P-MRS in identifying and distinguishing the three groups.HE staining,electron microscopy and desmin immunostaining after imaging of the muscle were used as a reference standard.The correlation between 31P-MRS and the mean absorbance （A value） of desmin staining were analyzed with the Pearson correlation test.Results Pi,PCr,Pi/PCr,and PCr/（PCr＋Pi） showed statistically significant intergroup differences （P＜0.05）.AUCs of Pi,PCr,Pi/PCr,and PCr/（PCr＋Pi） were 0.905,0.848,0.930,and 0.930 for the control and half-exhaustive groups,while sensitivity and specificity were 90％/85％,95％/55％,95％/80％,and 90％/85％,respectively.The AUCs of Pi,PCr,Pi/PCr and PCr/（PCr＋Pi） were 0.995,0.980,1.000,and 1.000 for the control and exhaustive groups,while sensitivity and specificity were 95％/90％,100％/90％,100％/95％,and 100％/95％,respectively.The AUCs of Pi,PCr,Pi/PCr,and PCr/（PCr＋Pi） were 0.735,0.865,0.903,and 0.903 for the half-exhaustive and exhaustive groups,while sensitivity and specificity were 80％/60％,90％/75％,95％/65％,and 95％/70％,respectively.In the half-exhaustive group,some muscle fibers exhibited edema in HE staining,and the unclear Z-discs and the mitochondria with vacuolar degeneration under electron microscopy.Compared with the half-exhaustive group,muscle fiber edema was increased in the exhaustive group,and the Z-discs were broken and the mitochondria exhibited marked vacuolar degeneration under electron microscopy.There were significant difference in A values of desmin staining in the right vastus lateralis among the control,half-exhaustive,and exhaustive groups with 0.58±0.06,0.30±0.04,and 0.21±0.02,respectively （P＜0.05）.Histological examination also showed injury-induced changes in the vastus lateralis among the different intensities groups.Statistically a moderate correlation between 31P-MRS and desmin was observed,the correlation coefficients of Pi,PCr,Pi/PCr,and PCr/（PCr＋Pi） were-0.706,0.709,-0.726,and 0.791,respectively （P＜0.01）.Conclusions 31P-MRS can effectively reflect the changes in energy metabolism in the skeletal muscle after a single bout of acute exhaustive swimming in rats.Based on the significant correlation between 31P-MRS parameters and histological changes,the changes of Pi,PCr,Pi/PCr,and PCr/（PCr＋Pi） can indirectly reflect the degree of exercise-induced injury.

Study on the differences between moxibustion at different points in the effects on the anti-fatigue ability of rats undergoing one-time exhaustive swimming

Objective:To observe the effects of moxibustion at Shenshu(BL 23),Zusanli(ST 36)and Shenque(CV 8)on the energy metabolism and endocrine metabolism indicators of rats undergoing one-time exhaustive swimming,and to explore the differences between moxibustion at different points in the effects on anti-exercise fatigue.Methods:Forty-eight male SPF rats were randomly divided into a blank group,a model group,a non-meridian and non-acupoint group,a Shenshu(BL 23)group,a Zusanli(ST 36)group,and a Shenque(CV 8)group using random number table method,with eight rats in each group.Except for the blank group,rats in the other groups were subjected to replicating the one-time exhaustive model using the weight-bearing swimming experiment.Except for the model group,the other model rats received mild moxibustion immediately after swimming.Rats in the non-meridian and non-acupoint group received mild moxibustion at bilateral subcostal non-meridian and non-acupoint points,those in the Shenshu(BL 23)group received mild moxibustion at bilateral Shenshu(BL 23),those in the Zusanli(ST 36)group received mild moxibustion at bilateral Zusanli(ST 36),and those in the Shenque(CV 8)group received mild moxibustion at Shenque(CV 8)for 15 min.Four hours after the exhaustive swimming,femoral artery blood was collected to detect blood lactate(BLA),lactate dehydrogenase(LDH),creatine kinase(CK),creatinine(CRE),blood urea nitrogen(BUN),cortisol(C)and testosterone(T)levels,and calculate the T/C ratio.Results:Compared with the blank group,rat's serum levels of BLA,LDH,CK,BUN and C in the model group and the non-meridian and non-acupoint group were increased,and serum levels of CRE and T,and T/C ratios were decreased(P<0.01 or P<0.05);compared with the model group and the non-meridian and non-acupoint group,the serum levels of BLA,LDH,CK,BUN and C in the Shenshu(BL 23)group,Zusanli(ST 36)group and Shenque(CV 8)group were decreased,and the serum CRE and T levels,and the T/C ratios were increased(all P<0.01);compared with the Shenshu(BL 23)group,the serum CK level was decreased in the Shenque(CV 8)group(P<0.01),the serum levels of T and C were decreased in the Zusanli(ST 36)group and Shenque(CV 8)group(P<0.01 or P<0.05),and the T/C ratio was increased in the Shenque(CV 8)group(P<0.01);compared with the Zusanli(ST 36)group,the serum CK and BUN levels were decreased(P<0.01,P<0.05),and the T/C ratio was increased in the Shenque(CV 8)group(P<0.05).Conclusion:Moxibustion at Shenshu(BL 23),Zusanli(ST 36)and Shenque(CV 8)shows different anti-fatigue effects by regulating the energy metabolism and endocrine metabolism in rats undergoing one-time exhaustive swimming.Moxibustion at Shenshu(BL 23)is better in promoting energy synthesis.Moxibustion at Shenque(CV 8)is more effective in regulating synthesis and decomposition of the skeletal muscle proteins.

Difference in the anti-fatigue effect of moxibustion at different acupoints in one-off exhausted rats

Objective:To explore the difference in the anti-fatigue effect of moxibustion at different acupoints through observing the impacts of moxibustion at"Shènshù(肾俞BL23)","Zúsānlǐ(足三里ST36)","Guānyuán(关元CV4)"and"Shénquè(神阙CV8)"on energy metabolic indexes in the one-off exhausted rats.Methods:A total of 56 SPF male rats were randomized into 7 groups,named a blank group,a model group,a non-acupoint group,a"BL23"group,a"ST36"group,a"CV4"group and a"CV8"group,8 rats in each group.The one-off exhaustion model was established by weight-bearing swimming experiment.Right after the exhaustive swimming of rats in each intervention group,the mild moxibustion was applied at the corresponding acupoints for 15 min immediately.4 h after the exhaustive swimming,the blood was collected from the femoral artery and the quadriceps femoris of the left hindlimb was stripped.The levels of blood lactate(BLD),lactate dehydrogenase(LDH),creatine kinase(CK)and blood urea nitrogen(BUN),the expressions of adenosine triphosphatease(ATP),fructose-6-phosphofructokinase(PFK)and malomdialdehyde(MDA)in the quadriceps femoris and the activity of superoxide dismutase(SOD)and catalase(CAT)were detected.Results:Compared with the model group and the non-acupoint group,the levels of serum BLD,LDH,CK and BUN were all lower those in the"BL23"group,the"ST36"group,the"CV4"group and the"CV8"group,indicating a statistical significance(all P<0.05).Compared with the model group and the nonacupoint group,PFK was higher in the"BL23"group,indicating a statistical significance(both P<0.05).Compared with the model group and the non-acupoint group,PFK was higher in the"ST36"group and the"CV4"group,indicating a statistical significance(all P<0.05).Conclusion:It was found in the research that moxibustion at"BL23""ST36""CV4"and"CV8"regulated the energy metabolism in the one-off exhausted rats so as to bring the anti-fatigue effect into play and the effect was different among the acupoints.Moxibustion at"CV8"may work on the prevention of the protein decomposition in the skeletal muscle and moxibustion at"BL23"may be against the oxidation in the skeletal muscle.