Polysaccharides from Polygonatum kingianum Collett & Hemsl ameliorated fatigue by regulating NRF2/HO-1/NQO1 and AMPK/PGC-1α/TFAM signaling pathways, and gut microbiota.

Polygonatum kingianum Coll & Hemsl is an important Chinese medicine used for enhancing physical function and anti-fatigue, and polysaccharides (PKPs) are considered as the main bioactive components. However, the mechanisms through which PKPs exert their anti-fatigue effects are not fully understood. This study aimed more comprehensively to explore the anti-fatigue mechanisms of PKPs, focusing on metabolism, protein expression, and gut flora, by using exhaustive swimming experiments in mice. Results showed a significant increase in the exhaustive swimming time of the mice treated with PKPs, especially in the high-dose group (200 mg/kg/day). Further studies showed that PKPs remarkably improves several fatigue-related physiological indices. Additionally, 16S rRNA sequence analysis showed that PKPs increased antioxidant bacteria (e.g., g_norank_f_Muribaculaceae) and the production of short-chain fatty acids (SCFAs), while reducing the abundance of harmful bacteria (e.g., g_Escherichia-Shigella and g_Helicobacter). PKPs also mitigated oxidative stress through activating the NRF2/HO-1 signaling pathway, and promoted energy metabolism by upregulating the expression of AMPK/PGC-1α/TFAM signaling pathway proteins. This research may offer theoretical support for incorporating PKPs as a novel dietary supplement in functional foods targeting anti-fatigue properties.

Antifatigue effects and antioxidant activity in polysaccharide fractions from Chinese yam bulbils.

Polysaccharides are the principal component in Chinese yam (Dioscorea opposita Thunb.) bulbils. The properties and antifatigue of polysaccharides from yam bulbils (PYB) were identified and compared. Their molecular weights (PYB-1 and PYB-2) were approximately 145 and 11 kDa, respectively, with active ß-configurations. Meanwhile, the antifatigue activities of PYBs were tested in mice via exhaustive swimming tests (EST). The EST results indicated that PYB-1 and PYB-2 significantly prolonged swimming time in mice (p < .05). Associated with this increase was a rise in hepatic glycogen content and antioxidant enzyme (superoxide dismutase (SOD), glutathione peroxidase (GSH-Px)) activity, along with a decline in blood urea nitrogen, lactic acid, and malondialdehyde levels. The results showed that molecular weight might contribute to the antifatigue effects of PYBs. Additionally, antioxidant tests showed that PYB-1 had stronger free-radical scavenging activity than PYB-2. Taken together, the findings indicated that PYBs exhibited effective antifatigue and antioxidant activities providing additional evidence supporting the use of PYBs as functional food ingredients for relieving fatigue.

Antifatigue effect of sea buckthorn seed oil on swimming fatigue in mice.

The effect of sea buckthorn seed oil (SSO) on exercise-induced fatigue in mice was explored. The animals were randomly divided into a normal control group, exercise-induced fatigue group (EFG), SSO low-dose group, SSO medium-dose group, and SSO high-dose group. The mice in all the groups underwent swimming training for 10 days. Those in the treatment groups received different amounts of SSO (0.85, 1.68, and 3.35 g/kg BW [body weight]) before the exercise. All the animals were sacrificed on the last day after an exhaustive swimming test, and serum, liver, and brain specimens were collected. In the exhaustive swimming test, the swimming durations in the SSO-treated animals were longer than those in the EFG. Furthermore, SSO reduced serum lactic acid, blood urea nitrogen, and hepatic malondialdehyde levels and increased liver glycogen level, hepatic superoxide dismutase level, hypothalamic dopamine content, and glutathione peroxidase level. The SSO treatment decreased hypothalamic 5-hydroxytryptamine content, lipid hydroperoxide level, NLRP3 inflammasome, and interleukin-1ß protein expression in the prefrontal cortex. Furthermore, it promoted the protein expression of nuclear factor erythroid 2-related factor 2 in the liver. SSO exhibited an excellent antifatigue effect, which may be related to its inhibition of oxidative and inflammatory injury and regulation of hypothalamic neurotransmitters. PRACTICAL APPLICATION: In the present study, the effect of sea buckthorn seed oil on fatigue in mice and its potential mechanism were explored. Taken together, the findings provide insight into the potential role of sea buckthorn seed oil in the development of antifatigue drugs.

Curcumin-Added Whey Protein Positively Modulates Skeletal Muscle Inflammation and Oxidative Damage after Exhaustive Exercise.

(1) Background: Exhaustive exercise can induce muscle damage. The consumption of nutritional compounds with the ability to positively influence the oxidative balance and an exacerbated inflammatory process has been previously studied. However, little is known about the nutritional value of curcumin (CCM) when mixed with whey protein concentrate (WPC). This study was developed to evaluate the effect of CCM-added WPC on inflammatory and oxidative process control and histopathological consequences in muscle tissue submitted to an exhaustive swimming test (ET). (2) Methods: 48 animals were randomly allocated to six groups (n = 8). An ET was performed 4 weeks after the start of the diet and animals were euthanized 24 h post ET. (3) Results: WPC + CCM and CCM groups reduced IL-6 and increased IL-10 expression in muscle tissue. CCM reduced carbonyl protein after ET compared to standard AIN-93M ET and WPC + CCM ET diets. Higher nitric oxide concentrations were observed in animals that consumed WPC + CCM and CCM. Consumption of WPC + CCM or isolated CCM reduced areas of inflammatory infiltrate and fibrotic tissue in the muscle. (4) Conclusions: WPC + CCM and isolated CCM contribute to the reduction in inflammation and oxidative damage caused by the exhaustive swimming test.

Prediction of exercise sudden death in rabbit exhaustive swimming using deep neural network.

BACKGROUND AND OBJECTIVE: Moderate exercise contributes to good health. However, excessive exercise may lead to cardiac fatigue, myocardial damage and even exercise sudden death. Monitoring the heart health has important implication to prevent exercise sudden death. Diagnosis methods such as electrocardiogram, echocardiogram, blood pressure and histological analysis have shown that arrhythmia and left ventricular fibrosis are early warning symptoms of exercise sudden death. Heart sounds (HS) can reflect the changes of cardiac valve, cardiac blood flow and myocardial function. Deep learning has drawn wide attention because of its ability to recognize disease. Therefore, a deep learning method combined with HS was proposed to predict exercise sudden death in New Zealand rabbits. The objective is to develop a method to predict exercise sudden death in New Zealand rabbits. METHODS: This paper proposed a method to predict exercise sudden death in New Zealand rabbits based on convolutional neural network (CNN) and gated recurrent unit (GRU). The weight-bearing exhaustive swimming experiment was conducted to obtain the HS of exercise sudden death and surviving New Zealand rabbits (n = 11/10) at four different time points. Then, the improved Viola integral method and double threshold method were employed to segment HS signals. The segmented HS frames at different time points were taken as the input of a combined CNN and GRU called CNN-GRU network to complete the prediction of exercise sudden death. RESULTS: In order to evaluate the performance of proposed network, CNN and GRU were used for comparison. When the fourth time point segmented HS frames were taken as input, the result shows that the proposed network has better performance with an accuracy of 89.57%, a sensitivity of 89.38% and a specificity of 92.20%. In addition, the segmented HS frames at different time points were input into CNN-GRU network, and the result shows that with the progress of the experiment, the prediction accuracy of exercise sudden death in New Zealand rabbits increased from 50.98 to 89.57%. CONCLUSION: The proposed network shows good performance in classifying HS, which proves the feasibility of deep learning in exploring exercise sudden death. Further, it may have important implications in helping humans explore exercise sudden death.

Oral treatment with the Chinese herbal supplements B307 enhances muscle endurance of ICR mice after exhaustive swimming via suppressing fatigue, oxidative stress, and inflammation.

Exhaustive exercise may damage muscles due to oxidative stress and inflammation and cause muscle fatigue and soreness. The study investigated the effects of Chinese herbal supplements (CHS) B307 on muscle endurance after exhaustive swimming (ES). Thirty-two male ICR mice were randomly divided into 4 groups: Sham + ES, pretreatment of CHS B307 + ES (Pre + ES), post-treatment of CHS B307 + ES (Post + ES), and dual treatment of CHS B307 + ES (Dual + ES). All mice were subjected to ES in the form of a forced swimming test. Then, we compared ES time (EST) as the index of muscular endurance. Also, we examined the fatigue, oxidative stress, inflammation, and damage in the muscle tissue among these groups by using immunohistochemistry (IHC), chemiluminescence, and biochemical analysis. Our results revealed that those mice of Pre + ES and Dual + ES groups had remarkably better EST than those mice of Sham + ES and Post + ES groups. Those mice with oral treatment of CHS B307(Pre + ES, Post + ES, and Dual + ES groups) showed significantly reduced leukocyte counts in the urine, and reduced levels of reactive oxygen species (ROS), neutrophils, and lactic acid in the blood than those mice of Sham + ES. In addition, those mice with oral treatment of CHS B307 (Pre + ES, Post + ES, and Dual + ES groups) showed significant alleviation of oxidative stress, inflammation, and damage in the muscle tissue than those mice of Sham + ES. Thus, we suggested that CHS B307 can be a functional sports supplement because it can enhance muscle endurance after exhaustive swimming via suppressing fatigue, oxidative stress, and inflammation.

Anti-Fatigue Activity of a Mixture of Stauntonia hexaphylla (Thunb.) Decaisne and Vaccinium bracteatum Thunb. Fruit Extract.

Stauntonia hexaphylla (Thunb.) Decaisne and Vaccinium bracteatum Thunb. are commonly used in traditional herbal medicine and food and both exhibit antioxidant and anti-inflammatory effects. Herein, hot-water extracts of Stauntonia hexaphylla (Thunb.) Decaisne and Vaccinium bracteatum Thunb. fruits (1:1 mixture) were used to produce a complex extract NET-1601. The anti-fatigue activity of NET-1601 was evaluated in an in vitro oxidative stress model induced by treating C2C12 myotubes with H2O2. An exhaustive swimming test (EST) in vivo model was established using ICR mice. NET-1601-treated C2C12 myotubes (50, 100, and 200 mg/mL) with H2O2-induced oxidative stress displayed significantly increased cell viability and ATP content, but significantly decreased levels of reactive oxygen species. All NET-1601-treated EST models demonstrated significantly higher maximum swimming rates than control mice. Furthermore, serum lactate, lactate dehydrogenase activity, non-esterified fatty acid, and intramuscular glycogen levels were higher in NET-1601-treated mice than in control mice. In addition, mRNA levels of regulatory factors involved in muscle mitochondrial fatty acid ß-oxidation increased upon NET-1601 treatment. Moreover, catalase, superoxide dismutase, glutathione-S-transferase, and liver glutathione content, and antioxidant activity were higher in NET-1601-treated mice than in control mice. Reduced malondialdehyde levels indicated that NET-1601 treatment inhibited exercise-induced lipid peroxidation. Together, these results suggest that NET-1601 retains antioxidant enzyme activity during oxidative stress, simultaneously enhancing both muscle function via glycogen and fatty acid oxidation, thereby exerting a positive effect on recovery from fatigue.

Diclofenac attenuates inflammation through TLR4 pathway and improves exercise performance after exhaustive swimming.

BACKGROUND: The use of NSAIDs has become a common practice to counteract the pro-inflammatory acute effects of exercise, in order to improve sports performance. The liver, due to its central role in energy metabolism, may be involved primarily in the process of ROS generation and consequently inflammation after exhaustive exercise. OBJECTIVE: To analyze the influence of diclofenac on the liver TLR4 pathway and time to exhaustion in rats submitted to repeated exhaustive swimming. METHODS: An exhaustive test was performed in order to mimic athletes' routine, and inflammatory status and oxidative stress markers were evaluated in the liver. Animals were divided into sedentary and exhaustion groups, with this last performing three exhaustive swimming bouts. At the same time, diclofenac or saline was pre-administered once a day for nine days. RESULTS: Data showed significantly increased COX-2, TLR4, and MyD88 protein content in the liver after exhaustive swimming bouts. The levels of pro-inflammatory cytokines also increased after exhaustive exercise, while these effects were attenuated in the group treated with diclofenac plus exhaustive swimming bouts. The anti-inflammatory modulation provoked by diclofenac treatment was associated with an increased time to exhaustion in the exercise bouts. The exhaustive exercise increased TBARS formation, but diclofenac treatment blunted this elevation, while GSH/GSSG ratios in both exhaustion-saline and exhaustion-diclofenac-treated groups were lower than in the sedentary-saline group. CONCLUSIONS: Our findings suggest that diclofenac may improve exercise performance and represent an effective tool to ameliorate the pro-inflammatory status in liver when associated with exhaustive exercise, and the liver may be a possible therapeutic target.

Lifetime overproduction of circulating angiotensin-(1-7) in rats attenuates the increase in skeletal muscle damage biomarkers after exhaustive exercise.

Angiotensin-(1-7) (Ang-[1-7]) can modulate glucose metabolism and protect against muscular damage. The aim of this study was to investigate the influence of lifetime increase of circulating levels of Ang-(1-7) at exhaustive swimming exercise (ESE). Sprague-Dawley (SD) and transgenic rats TGR(A1-7)3292 (TR) which overproduce Ang-(1-7) (2.5-fold increase) were submitted to ESE. The data showed no differences in time to exhaustion (SD: 4.90 ± 1.37 h vs. TR: 5.15 ± 1.15 h), creatine kinase, and transforming growth factor beta (TGF-ß). Lactate dehydrogenase (SD: 219.9 ± 12.04 U/L vs. TR: 143.9 ± 35.21 U/L) and α-actinin (SD: 336.7 ± 104.5 U/L vs. TR: 224.6 ± 82.45 U/L) values were significantly lower in TR. There was a significant decrease in the range of blood glucose levels (SD: -41.4 ± 28.32 mg/dl vs. TR: -13.08 ± 39.63 mg/dl) in SD rats. Muscle (SD: 0.06 ± 0.02 mg/g vs. TR: 0.13 ± 0.01 mg/g) and hepatic glycogen (SD: 0.66 ± 0.36 mg/g vs. TG: 2.24 ± 1.85 mg/g) in TR were higher. The TR presented attenuation of the increase in skeletal muscle damage biomarkers and of the changes in glucose metabolism after ESE.

Moxibustion Reduces Inflammatory Response in the Hippocampus of a Chronic Exercise-Induced Fatigue Rat.

Accumulating data indicates that brain inflammation plays an important role in the pathophysiology of chronic exercise-induced fatigue. Moxibustion in traditional Chinese medicine has been found to alleviate exercise-induced fatigue. However, it remains unclear whether the effect of moxibustion is related to its anti-inflammatory properties. In this study, rats were exposed to 3-week exhaustive swimming to induce chronic exercise-induced fatigue. The body weight, exhaustive swimming time, tail suspension test and open-field test were observed. Real-time polymerase chain reaction (RT-PCR) was used to determine the mRNA expression of proinflammatory cytokines (interleukin-1ß [IL-1ß], interleukin-6 [IL-6], and tumor necrosis factor-α[TNF-α]), and enzyme-linked immunosorbent assay (ELISA) was used to detect IL-1ß, IL-6, and TNF-α concentrations. Chronic exhaustive exercise significantly reduced the body weight and exhaustive swimming time, and increased tail suspension immobility time, which were reversed by moxibustion treatment. Compared with control rats, the mRNA and protein expression of IL-1ß, IL-6, and TNF-α in the hippocampus was significantly increased in exhaustive swimming trained rats. Moxibustion significantly decreased the level of IL-6 in the hippocampus, but not affected IL-1ß and TNF-α level significantly. Our results suggested that a potential inflammatory damage in the brain may be involved during chronic exhaustive exercise-induced fatigue. Moxibustion could attenuate the inflammatory impairment in exercise-induced fatigue, which might be mediated by inhibition of the proinflammatory cytokine IL-6 levels in the brain region.

Effects of sildenafil citrate on peripheral fatigue and exercise performance after exhaustive swimming exercise in rats.

Sildenafil citrate is a potent and selective inhibitor of phosphodiesterase type-5 used to treat erectile dysfunction. We investigated the effects of sildenafil citrate treatment on peripheral fatigue and exercise performance after exhaustive swimming exercise in rats. The rats in the sildenafil citrate-treated groups received sildenafil citrate orally once a day for 14 consecutive days at respective dosage. On the 14 days after starting experiment, each animal was submitted to swimming test with intensity equivalent to overload. The exhaustion was defined as a state in which coordinated movements did not return to the water surface for breathing within 10 sec. Western blot for monocarboxylate transporter (MCT)1, MCT4, and neuronal nitric oxide synthase (nNOS) were performed. Exhaustive swimming exercise decreased time of exhaustion and increased lactate concentration, however, sildenafil citrate enhanced time of exhaustion and decreased lactate concentration. Exhaustive swimming exercise increased MCT1 and MCT4 expressions in the gastrocnemius muscles and sildenafil citrate further enhanced MCT1 and MCT4 expressions in the exhaustive swimming exercise rats. Exhaustive swimming exercise decreased nNOS expression in the gastrocnemius muscles and sildenafil citrate enhanced nNOS expression in the exhaustive swimming exercise rats. The most potent effect appeared in the 20-mg/kg sildenafil citrate. Sildenafil citrate might be proposed as a potential ergogenic aid through antiperipheral fatigue.

[Study on establishment of an animal model of Qi deficiency syndrome base on theory of over exertion leading to Qi consumption in traditional Chinese medicine].

Based on the theory of "overexertion leading to Qi consumption", this study aimed to compare the intervention factors of nervous and physical fatigue to establish a rat model of Qi deficiency syndrome, moreover, the systematic evaluationsystem was necessary with the standard of syndrome diagnosis of Qi deficiency. According to the clinical-mimetic principle the Qi deficiency syndrome animal model is established by the factors of sleep deprivation(SD) and exhaustive swimming(ES). Rats were randomly divided into four groups, normal group, SD group, ES group and compound group (exhaustion swimming complex sleep deprivation). The method of ES was force rats to swim until the exhaustion with 5% of weight, and the SD method by using multi-platform sleep deprivation of water environment randomly 14-16 h daily, and the complex set by using of two methods was combined. The movement distance, average speed, activity time and numbers into the central area were detected by open field test, swimming exhaustion time was detected by swimming exhaustion method, the cardiac function (LVEF, CO, FS, LVDd) was detected by echocardiography, tongue imaging analysis and pulsedistention as the index of tongue and pulse diagnosis, the content of ATP and ADP in serum was detected by ELISA, the blood coagulation indexes for blood stasis syndrome as the additional. These results indicated that independent activity, body weight and exercise capacity were decreased significantly, the neurological function injured significantly, heart function was decreased significantly, the tongue surface color was pale white, and the pulse distention was decreased significantly. The content of ATP decreased significantly and the ADP increased significantly. By the method of four-diagnostic evaluation system to compare the factors of SD and ES, the Qi deficiency syndrome animalmodel could be successfully established by sleep deprivation method.

Experimental studies on anti-fatigue effects and spectra-effect relationship of different extracts from black Lepidium meyenii (Maca) / 中草药

Objective To investigate the anti-fatigue effects and the relationship between UPLC and anti-fatigue effects of different extracts of black Maca, and to provide a basis for clarifying the material basis of anti-fatigue effects of black Maca. Methods Anti- fatigue effects of eight different extracts of black Maca were evaluated through exhaustive swimming time, contents of liver glycogen, and lactic acid in serum; UPLC-Q-TOF/MS was applied to establish the fingerprints for black Maca from eight extracts; Using the anti-fatigue effects of exhaustive swimming experiment as pharmacodynamic indicators, spectra-effect relationship was analyzed by using PLSR. Results 60%, 80%, and 95% ethanol extracts of black Maca could significantly prolong the exhaustive swimming time of mice, with the effects of 95% ethanol extract of black Maca was the strongest; The treatment of 80% ethanol extract of black Maca significantly increased the level of depressed hepatic glycogen due to excessive exercise; Moreover, 95% ethanol extract of black Maca substantially decreased the serum lactic acid accumulation after loaded-swimming. A total of 23 characteristic peaks were characterized by HPLC fingerprints of eight different extracts of black Maca. N-benzylhexadecanamide, N-benzyl-5-oxo-6E,8E-octadecadienamide, 1,3-dibenzyl-2-phenyl-4,5-dimethylimidazilium, and N-octadecanamide were found to be positively related to the anti-fatigue effects with VIP > 1 in extracts of black Maca from PLSR analysis by using anti-fatigue effects of exhaustive swimming time as pharmacodynamic indicators. Conclusion 95% and 80% ethanol extracts of black Maca showed the obvious anti-fatigue function. It is clear that four components N-benzylhexadecanamide, N-benzyl-5-oxo-6E,8E-octadecadienamide, 1,3-dibenzyl-2-phenyl-4,5-dimethylimidazilium, and N-octadecanamide are the principal anti-fatigue substances in black Maca. The study has the contribution to to explore the material basis of anti-fatigue effects and provides new ideas for the omprehensive and reliable quality control of black Maca.

Study on establishment of an animal model of Qi deficiency syndrome base on theory of over exertion leading to Qi consumption in traditional Chinese medicine / 中国中药杂志

Based on the theory of "overexertion leading to Qi consumption", this study aimed to compare the intervention factors of nervous and physical fatigue to establish a rat model of Qi deficiency syndrome, moreover, the systematic evaluationsystem was necessary with the standard of syndrome diagnosis of Qi deficiency. According to the clinical-mimetic principle the Qi deficiency syndrome animal model is established by the factors of sleep deprivation(SD) and exhaustive swimming(ES). Rats were randomly divided into four groups, normal group, SD group, ES group and compound group (exhaustion swimming complex sleep deprivation). The method of ES was force rats to swim until the exhaustion with 5% of weight, and the SD method by using multi-platform sleep deprivation of water environment randomly 14-16 h daily, and the complex set by using of two methods was combined. The movement distance, average speed, activity time and numbers into the central area were detected by open field test, swimming exhaustion time was detected by swimming exhaustion method, the cardiac function (LVEF, CO, FS, LVDd) was detected by echocardiography, tongue imaging analysis and pulsedistention as the index of tongue and pulse diagnosis, the content of ATP and ADP in serum was detected by ELISA, the blood coagulation indexes for blood stasis syndrome as the additional. These results indicated that independent activity, body weight and exercise capacity were decreased significantly, the neurological function injured significantly, heart function was decreased significantly, the tongue surface color was pale white, and the pulse distention was decreased significantly. The content of ATP decreased significantly and the ADP increased significantly. By the method of four-diagnostic evaluation system to compare the factors of SD and ES, the Qi deficiency syndrome animalmodel could be successfully established by sleep deprivation method.

Content Determination of Phenylpropanoids and Enhancing Exercise Ability of Effective Fractions in Pedicularis densispica.

BACKGROUND: Most researches were focused on chemical constituents and bioactivities of Pedicularis. However, there were a few reports on simultaneous determination of the series phenylpropanoids compounds in Pedicularis by High Performance Liquid Chromatography (HPLC). OBJECTIVE: To establish an HPLC method for simultaneous determination of salidroside, verbascoside, iso-verbascoside, leucoseptoside A, jionoside D and martynoside in Pedicularis densispica (PD), and to assess the enhancing exercise ability of effective fractions of phenylpropanoids (EFP). MATERIALS AND METHODS: The separation was performed on C18 column with step-wise gradient elution with water (A)-methanol (B) as the mobile phase at a flow rate of 1.0 mL/min, with detection wavelength at 275 nm (0-4 min) and 330 nm (4-40 min). The EFP were obtained from extracts of PD by resin gradient dilution. The enhancing exercise ability of EFP was exerted in exhaustive swimming and anoxia endurance tests in vivo. RESULTS: The contents of six marker compounds had good linear relationship in the ranges of 2.10-8.40, 13.60-54.40, 0.93-3.72, 0.53-2.12, 1.50-6.00, 0.37-1.28, respectively, and the average recoveries of the six phenylpropanoids were all in the range of 98-103%. Total contents of phenylpropanoids in EFP were more than 60%. Three medicine groups of exhaustive swimming and anoxia endurance time were higher than those of the water group. CONCLUSION: The analytical method is reliable, simple and accurate, and can be used for the comprehensive quality control of PD. This experiment suggests that PD has the effect of promoting the recovery and elimination of fatigue and improving the exercise capacity. SUMMARY: A simple, practical and low-cost RP-HPLC method has been developed for the simultaneous determination of six marker phenylpropanoids in Pedicularis densispica.Three effective fractions of phenylpropanoids groups of exhaustive swimming and anoxia endurance time were higher than those of the water group.The separation was performed on C18 column with stepwise gradient elution with water-methanol. The enhancing exercise ability was exerted in exhaustive swimming and anoxia endurance tests in vivo.This plant has the effect of promoting the recovery and elimination of fatigue and improving the exercise capacity. Abbreviation used: PD: Pedicularis densispica, EFP: Effective fractions of phenylpropanoids, DAD: Diode array detector, HPLC: High performance liquid chromatography, LOD: Limits of detection, LOQ: Limits of quantification, RSD: Relative standard deviation, BV: Bed volumes.

Nigella sativa seed extract attenuates the fatigue induced by exhaustive swimming in rats.

In previous studies, Nigella sativa (NS) has been studied due to its various physiological and pharmacological activities. However, evidence on the effects of NS on physical fatigue following exhaustive swimming remains limited. In the present study, the authors evaluated the potential beneficial effects of NS against the fatigue activity following exhaustive swimming. Rats were orally administered with NS extract (2 g/kg/day) for 21 days, and the anti-fatigue effect was assessed by exhaustive swimming exercise. The presented results indicated that pre-treatment of NS extract significantly increased the time to exhaustion. In hemodynamic parameters, NS extract increased blood pO2 and O2sat, but decreased pCO2. For underlying mechanisms, NS extract protected depletion of energy, indicated by increased levels of blood pH, glucose and tissue glycogen contents, and decreased levels of blood lactate, tissue lactic dehydrogenase and creatine kinase, when the NS extract was pre-treated. In addition, the NS extract inhibited oxidative stress following exhaustive swimming, as reflected by the results of increased levels of superoxide dismutase and redox ratio, and decreased the level of malondialdehyde when the NS extract was pre-treated. Collectively, the present study demonstrated that NS extract has an anti-fatigue activity against exhaustive swimming by energy restoration and oxidative-stress defense.

Antifatigue effects of troxerutin on exercise endurance capacity, oxidative stress and matrix metalloproteinase-9 levels in trained male rats.

The aim of this study was to investigate effects of troxerutin (TRX) on endurance capacity, oxidative stress and matrix metalloproteinase-9 (MMP-9) levels in trained male rats. Forty male Wistar rats were divided into five groups. The control (Vehicle) and exercise training (5 days/week) with vehicle treatment (Exercise), exercise training with TRX treatment at 75 (Ex-TRX75), 150 (Ex-TRX150), and 300 mg/kg (Ex-TRX300). The treated groups received TRX by gavage every day while the other groups received water for 30 days. On the 30th day, rats were sacrificed immediately after exhaustive swimming test, and some biochemical parameters were measured. Exhaustion swimming time in the Ex-TRX75, Ex-TRX150 and Ex-TRX300 groups significantly increased 1.2-, 1.93- and 2.1-fold compared to the vehicle group, respectively. TRX significantly increased glucose level (P < 0.05) and reduced creatine kinase activity (P < 0.001) compared to the vehicle and exercise groups. TRX300 significantly reduced alkaline phosphatase and lactate dehydrogenase activities (P < 0.05) and blood urea nitrogen (P < 0.05) and MMP-9 levels (P < 0.05) compared to the vehicle and exercise groups. Additionally, TRX300 and TRX150 significantly increased superoxide dismutase activity compared to the vehicle group (P < 0.05). Our results provide experimental evidence in supporting clinical use of TRX as an effective agent against fatigue.

Effects of naringin on physical fatigue and serum MMP-9 concentration in female rats.

CONTEXT: Oxidative stress has a critical role in the development of physical fatigue and activation of matrix metalloproteinases-9 (MMP-9). Naringin (Nar) is a bioflavonoid that has antioxidant activity and suppresses MMP-9 expression. OBJECTIVE: The present study evaluates the anti-fatigue activity of Nar on physical fatigue and serum MMP-9 concentration in rats. MATERIALS AND METHODS: Fifty female Wistar rats were randomly divided into five groups (n = 10); a control group, vehicle group and three Nar treatment groups. The Nar treated groups received different doses of Nar (40, 80 and 160 mg/kg/day) for 30 days. On the 30th day, rats were sacrificed immediately after exhaustive swimming test. Serum MMP-9 concentration and several biochemical parameters related to fatigue were measured. RESULTS: Exhaustive swimming time in the Nar-80 group significantly increased 1.78-, 1.53-, 1.5- and 1.3-fold compared with the control, vehicle, Nar-40 and Nar-160 groups, respectively. In addition, exhaustive swimming time in the Nar-160 group significantly increased 1.36-fold compared with the control group. Nar-80 significantly decreased LDH activity by 60.45% and 57.47% compared with the vehicle and control groups, respectively. Furthermore, Nar-80 and Nar-160 increased blood glucose levels by 19.56% and 18.38% compared with the control group, respectively. Nar-80 and Nar-160 significantly decreased serum MMP-9 concentration by 61.57% and 83.39% compared with the control group, respectively. CONCLUSION: Based on our data, Nar has anti-fatigue effects which may be attributed to its property in modulating energy metabolism and reducing serum MMP-9 concentration. Thus, Nar may be a promising agent for the treatment of physical fatigue.

Optimization of chronic heart failure model induced by coronary artery ligation in rats with swimming exhaustion / 中国临床药理学与治疗学

AIM:To establish the rat model of ischemic chronic heart failure by coronary artery ligation combining with exhaustive swimming.METHODS:40 adult rats were treated with coronary artery ligation,after 4 weeks cardiac function measurement were conducted by ultrasonography.Rats with LVEF below 40％ are considered as successful model duplication.11 rats were collected for the coronary artery ligation group,while the rest (whose LVEF were bigger than 40％) were pushed to swim for 1h per day by 15 days to promote the model formation which 8 rats were collected for exhaustion with ligation group.Left ventricular function indexes,brain natriuretic peptide (BNP) and cardiac histomorphologic changing were checked,and compared with the Control group (10 rats).RESULTS:LVEF of exhaustion with ligation group was (38.70 ± 10.10) ％,coronary artery ligation group (39.20 ± 11.10)％,which was obviously decreasing (P ＜ 0.01) compared with that of the control group (84.60 ± 3.64) ％.LVEDP of exhaustion with ligation group was (11.5 ± 1.3) mm Hg,coronary artery ligation group [(10.68 ± 4.45)mm Hg],which was obviously increasing (P ＜ 0.01)compared with that of the Control group [(4.4 ± 0.2) mm Hg].The BNP level of exhaustion with ligation group was (561.0 ± 21.0) μg/L,coronary artery ligation group (548.6 ± 25.8) μg/L,which was obviously increasing (P ＜0.01) compared with that of control group [(366.2 ± 21.8) μg/L].There are lots of red myocardial cells with stripe clear in the control group based on Masson's trichrome staining,but there are so many blue collagenous fibers instead of myocardial cells in exhaustion with ligation group and coronary artery ligation group.The standard-reaching rate of model was about 35％ at 4 weeks after operation,while final standard-reaching rate rose to about 62％ after exhausting swimming.Although the difference between the indexes of the coronary artery ligation group and the post ligation group was not significant,the rate of improvement was significant (P ＜ 0.01).CONCLUSION:Ligation of coronary artery combined with swimming exhaustion can establish ischemic chronic heart failure model,which is more economic and can obtain high success rate,thus is suitable to generalization.

Anti-fatigue effect of arginyl fructosyl glucose from red ginseng in mice / 吉林大学学报(医学版)

Objective:To investigate the anti-fatigue phenomenon induced by forced swimming in the mice,and to explore the anti-fatigue effect of argininyl fructoyl glucose (AFG) from red ginseng in the mice and its mechanism.Methods:The AFG was extracted from red ginseng.The ICR mice were divided into blank control group,low dose of AFG group (100 mg · kg-1),middle dose of AFG group (200 mg · kg-1) and high dose of AFG group (400 mg · kg-1) (n=20).The mice mere given a forced swimming test after continuous gavage for 28 d.The weights,organ indexes,time of forced swimming,contents of lactic acid (LD),blood urea nitrogen (BUN),hepatic glycogen (Gly) and expressing levels of PGC-1α in gastrocnemius of the mice in various groups were detected.Results:Compared with blank control group,the weights and organ indexes of the mice in low,middle and high doses of AFG groups had no significant differences (P＞ 0.05).Compared with blank control group,the time of forced swimming,contents of Gly and expressing levels of PGC-1α of the mice in low,middle and high doses of AFG groups were significantly increased (P＜0.05 or P＜0.01) in a dose-dependent manner.Compared with blank control group,The contents of LD and BUN in serum of the mice in low,middle and high doses of AFG groups were significantly decreased (P＜0.01).Conclusion:AFG has anti-fatigue effect in mice,and its mechanism may be related to energy metabolism.