Muscle Glycogen Content Research Articles

Synergistic effect of combined oyster peptide and ginseng extracts on anti-exercise-fatigue and promotion of sexual interest activity in male ICR mice

• Novelty, a synergistic effect of OPGE on anti-fatigue and sexual ability was explored. • OPGE promoted physical recovery and accelerated fatigue elimination. • OPGE increased sexual behavior of male mice after exhausted swimming. • OPGE enhanced the expression of testosterone synthesis related protease. Traditionally, ginseng and oyster are regarded as biological tonics for enhancing vital energy. In this study, a post-exercise fatigue model and copulatory test were performed to evaluate the effects of combined oyster peptide and ginseng extracts (OPGE) on anti-fatigue and sexual function. The forced swimming time of mice was prolonged by taking OPGE. Moreover, the level of serum lactic acid, blood urea nitrogen, and lactate dehydrogenase activity were decreased, while the liver glycogen content and antioxidant ability in skeletal muscles were increased. Furthermore, OPGE statistically improved the sexual behavioral indexes of exercise-fatigue mice. The levels of testosterone and follicle-stimulating hormone in serum, and the expression of testosterone synthesis-related-protease in testis were increased by OPGE administration, while phosphodiesterase-5 content was decreased. Overall, our study suggested that OPGE could be a potential androgen-like dietary supplement to accelerate the elimination of fatigue and improve testosterone-deficiency symptom after intensive training.

Effect of Early Feeding (in Ovo) With Nano-Selenium and Vitamin E on Body Weight and Glycogen Level in Broiler Chickens Exposed to Fasting Condition

This study aimed to reduce the severity of stress on incubating chicks as a result of long staying in hatcheries and exposure to food fasting as well as evaluate its subsequent growth performance. In present study, 750 fertilized eggs were used with divided into 5 treatments, each treatment contains 150 eggs, the first treatment (T1) is a negative control treatment without injection and the second treatment (T2) is a positive control treatment injected with distilled water. The treatments (T3, T4, and T5) were injected with a solution containing vitamin E, nano-selenium at concentrations of (15, 30, 45 mg/ml), respectively. The hatching chicks were divided from the injected egg treatments, where each treatment was divided into 3 replicates and the chicks were starved for 48 hours without providing them feed and they provided with water only. According to results, a significant increase occurred for the treatments (T3, T4, and T5) in weight at hatching and weight at age of 48 hours compared to positive and negative control treatments (T1 and T2). Significant increase occurred for the T5 treatment in the glycogen content of liver with a significant level and for the age at the hatching of (12, 24, 48 hr of bird age), respectively. Significant increase occurred for the treatments (T3 and T5) in the concentration of cardiac glycogen at hatching and at the age of (12 hr). The significant of the T5 treatment continued at the age of (24 and 48 hr) compared to the rest of the treatments. Significant increase occurred for the treatments (T3, T4 and T5) in the concentration of muscle glycogen compared to the treatments (T1 and T2). The results showed that nano-selenium and vitamin E improved the performance of embryonic growth and increased the weight of hatching chicks as well as increasing the level of glycogen in the liver, muscles and heart muscles.

Salbutamol Increases Leg Glucose Uptake and Metabolic Rate but not Muscle Glycogen Resynthesis in Recovery From Exercise.

Exercise blunts the effect of beta2-agonists on peripheral glucose uptake and energy expenditure. Whether such attenuation extends into recovery is unknown. To examine the effect of a beta2-agonist on leg glucose uptake and metabolic rate in recovery from exercise. Using leg arteriovenous balance technique and analyses of thigh muscle biopsies, we investigated the effect of a beta2-agonist (24 mg of oral salbutamol) vs placebo on leg glucose, lactate, and oxygen exchange before and during quadriceps exercise, and 0.5 to 5 hours in recovery from quadriceps exercise, as well as on muscle glycogen resynthesis and activity in recovery. Twelve healthy, lean, young men participated. Before exercise, leg glucose uptake was 0.42 ± 0.12 and 0.20 ± 0.02 mmol × min-1 (mean ± SD) for salbutamol and placebo (P = .06), respectively, while leg oxygen consumption was around 2-fold higher (P < .01) for salbutamol than for placebo (25 ± 3 vs 14 ± 1 mL × min-1). No treatment differences were observed in leg glucose uptake, lactate release, and oxygen consumption during exercise. But in recovery, cumulated leg glucose uptake, lactate release, and oxygen consumption was 21 mmol (95% CI 18-24, P = .018), 19 mmol (95% CI 16-23, P < .01), and 1.8 L (95% CI 1.6-2.0, P < .01) higher for salbutamol than for placebo, respectively. Muscle glycogen content was around 30% lower (P < .01) for salbutamol than for placebo in recovery, whereas no treatment differences were observed in muscle glycogen resynthesis or glycogen synthase activity. Exercise blunts the effect of beta2-agonist salbutamol on leg glucose uptake, but this attenuation diminishes in recovery. Salbutamol increases leg lactate release in recovery, which may relate to glycolytic trafficking due to excessive myocellular glucose uptake.

Anti-fatigue effect of quercetin on enhancing muscle function and antioxidant capacity.

The aim of this study was to evaluate the anti-fatigue effect of quercetin in mice. Three-week-old male BALB/c mice, fed with/without 0.005% quercetin for 6weeks, were randomly divided into two experimental sets (loaded swimming and non-loading swimming tests). Our data indicated that dietary quercetin supplementation prolonged the exhaustive swimming time. In addition, lactic acid (LD) and blood urea nitrogen (BUN) levels, lactate dehydrogenase (LDH) and creatine kinase (CK) activities in serum were significantly decreased, while the levels of non-esterified free fatty acids (NEFA) in serum and the content of liver glycogen and muscle glycogen were significantly enhanced in dietary quercetin supplementation group. Furthermore, dietary quercetin supplementation significantly enhanced the glutathione peroxidase (GPx) and catalase (CAT) activities in serum, liver and gastrocnemius muscle and enhanced the total superoxide dismutase (T-SOD) activity in gastrocnemius muscle, but decreased the malondialdehyde (MDA) content and reactive oxygen species (ROS) level. Meanwhile, dietary quercetin supplementation affected the mRNA expression of regulators factors involved in muscle damage and inflammation, glucose metabolism and gluconeogenesis, muscle mitochondrial fatty acid β-oxidation and antioxidant related genes. Together, our data confirm that dietary quercetin supplementation can promote anti-fatigue capacity by promoting the antioxidant capacity and glycogen storage, as well as enhancing muscle function. PRACTICAL APPLICATIONS: Quercetin is a natural polyphenolic flavonoid substance. Here we confirm that quercetin has anti-fatigue activity. Our study indicates that quercetin may be used as natural anti-fatigue functional food or drugs.

TRPV1 Receptor-Mediated Hypoglycemic Mechanism of Capsaicin in Streptozotocin-Induced Diabetic Rats.

Our previous research showed that capsaicin exhibits hypoglycemic effects by activating the transient receptor potential vanilloid 1 (TRPV1) channel in diabetic rats. Interestingly, capsiate was also able to activate the TRPV1 channel, but with a non-significant hypoglycemic effect. This study aimed to investigate the effect of capsaicin on the glycometabolism of streptozotocin (STZ)-induced diabetic rats by blocking the TRPV1 channel. After a 4-week capsaicin treatment (6 mg/kg·bw), the serum insulin level of STZ-induced diabetic rats increased from 15.2 to 22.1 mIU/L, the content of hepatic glycogen and muscle glycogen increased by 81.2 and 20.2%, respectively, and the blood glucose level decreased significantly from 19.3 to 14.7 mmol/L. When the TRPV1 channel was blocked, capsaicin lost the above-mentioned effects, and the hypoglycemic effect was no longer significant. It was concluded that a combined up-regulation of both TRPV1 receptors and pancreatic duodenal homeobox-1 (PDX-1) led to the hypoglycemic effect of capsaicin, which partially explains our previous observation: capsiate activating TRPV1 without showing a significant hypoglycemic effect was due to the lack of a significant up-regulation of PDX-1. Based on the experimental results, we speculated that two signaling pathways [TRPV1-(PDX1)-(GLUT2/GK) and TRPV1-(PDX-1)-(IRS1/2)] exist in the pancreas of STZ-induced diabetic rats.

Effects of glimepiride on growth, glucose metabolism and expression of p38MAPK, JNK in skeletal muscles of GIFT tilapia

This study aimed to investigate the effects of glimepiride on the growth, glucose metabolism and the expressions of p38 mitogen-activated protein kinases (p38MAPK), C-JUN N-terminal kinase (JNK) in skeletal muscle of genetically improved farmed tilapia (GIFT). The tilapia were categorized into five feed groups: normal starch group (32%, LS), high starch group (53%, HS), HS+ glimepiride group 1 (10 mg/kg, G1), HS+ glimepiride group 2 (20 mg/kg, G2), and HS+ glimepiride group 3 (30 mg/kg, G3). The results showed that the final body weight and specific growth rate of the G2 group increased (P > 0.05), and the protein efficiency ratio of groups G1 and G2 was significantly higher than that of the HS group (P < 0.05). The blood glucose content of groups G2 and G3 decreased, compared to that of the HS group. An increase in the glimepiride concentration led to the decreased serum glucose content of the G1 and G2 groups. Compared with the HS group, the insulin content of the G1, G2, and G3 groups significantly decreased, and the hepatic and muscle glycogen content in these three groups increased gradually with an increase in the glimepiride concentration (P > 0.05). The expression of p38MAPK and JNK mRNAs in the G1 and G2 groups were significantly lower than those in the HS groups (P < 0.05). In the G2 and G3 groups, p-p38MAPK and p-JNK protein expression were significantly lower than that in the HS group (P < 0.05); meanwhile, the p-JNK protein expression in G1 and G2 groups was lower than that in the HS group (P > 0.05). Thus, GIFT tilapia can tolerate a high amount of starch, and the addition of glimepiride at an optimal dosage of 10–20 mg/kg does not significantly impact the growth index. However, it can improve glucose metabolism by promoting insulin secretion and liver/muscle glycogen synthesis.

Effects of Nanometer Hydroxyapatite Aqueous Solution on Anaerobic Motor Ability of Mice

Nanometer hydroxyapatite is a new biomaterial with development potential. Its main components are very similar to those found in animal teeth. It has good biocompatibility and bioactivity. Can be closely bound to human tissue, repair tissue. With relatively more biosorption sites, it can be used as a protein carrier as an important strategy to fight cancer or promote the efficiency of tissue repair. It is widely used in biomedical fields, such as release carrier and tissue repair. With the development of modern medicine, the performance and application of nanometer hydroxyapatite are required. The purpose of this paper is to observe the effect of nanometer hydroxyapatite hydrosol on the anaerobic exercise ability of mice, and explore the mechanism of nanometer hydroxyapatite hydrosol on the anaerobic exercise ability of mice, which is of great significance for the application of nanometer hydroxyapatite in medicine and competitive sports. In this experiment, mathematical statistics were used to analyze the anaerobic swimming exhaustion time of mice in the nanometer hydroxyapatite injection group, sodium bicarbonate injection group, distilled water injection group and blank control group. The blood lactic acid content and immediate skeletal muscle lactic acid content of mice after anaerobic exercise were determined by statistical method. Finally, big data analysis method was used to fit the data and analyze the myocardial lactic acid value, skeletal muscle glycogen content and myocardial muscle glycogen content of mice injected with nano-hydroxyapatite sol after anaerobic swimming exhaustion. The experimental data showed that after the injection of nanometer hydroxyapatite hydrosol, the movement ability of mice increased. Experimental data showed that the nanometer hydroxyapatite hydrosol could improve the anaerobic exercise ability of mice, by neutralizing the lactic acid produced by the anaerobic exercise blood cells and cardiac muscle cells of mice, and prevent the accumulation of lactic acid, thereby increasing the anaerobic exercise ability by 40%, which is of great significance for athletes' exercise guidance in competitive sports.

Effects of post-exercise glucose ingestion at different solution temperatures on glycogen repletion in mice.

Carbohydrate ingestion is essential for glycogen recovery after exercise. Although studies have investigated methods for enhancement of glycogen repletion with regard to nutrients and their amounts, no studies have examined the effect of temperature of the ingested solution on glycogen recovery. Therefore, this study aimed to investigate the effect of the temperature of glucose solution ingested after exercise on glycogen recovery. Seven‐week‐old male ICR mice were fasted for 16 h and subjected to treadmill running exercise (20 m/min for 60 min) to decrease glycogen storage. Then, the mice were administered glucose (1.5 mg/g body weight) at three different solution temperatures: 4°C, cold solution group (Cold); 37°C, mild solution group (Mild); and 55°C, hot solution group (Hot). Our results revealed that blood glucose, plasma insulin, and muscle glycogen concentrations did not differ among the three groups. In contrast, liver glycogen concentration in the Hot group was significantly higher than that in the post‐exercise and Cold groups (p < 0.05). Furthermore, portal glucose concentration was significantly higher in the Hot group than in the Cold group (p < 0.01). These observations suggest that postexercise muscle glycogen repletion occurs regardless of glucose solution temperature, and that ingesting hot glucose solution after exercise can be an effective means for liver glycogen repletion compared with cold glucose solution ingestion.

Acute Administration of Exogenous Lactate Increases Carbohydrate Metabolism during Exercise in Mice.

In this study, we investigated the effects of exogenous lactate administration before exercise on energy substrate utilization during exercise. Mice were divided into exercise control (EX) and exercise with lactate intake (EXLA) groups; saline/lactate was administered 30 min before exercise. Respiratory gas was measured during moderate intensity treadmill exercise (30 min). Immediately after exercise, blood, liver, and skeletal muscle samples were collected and mRNA levels of energy metabolism-related and metabolic factors were analyzed. At 16–30 min of exercise, the respiratory exchange ratio (p = 0.045) and carbohydrate oxidation level (p = 0.014) were significantly higher in the EXLA than in the EX group. Immediately after exercise, the muscle and liver glycogen content and blood glucose level of the EXLA group were lower than those of the EX group. In addition, muscle mRNA levels of HK2 (hexokinase 2; p = 0.009), a carbohydrate oxidation-related factor, were higher in the EXLA than in the EX group, whereas the expression of PDK4 (pyruvate dehydrogenase kinase 4; p = 0.001), CS (citrate synthase; p = 0.045), and CD36 (cluster of differentiation 36; p = 0.002), factors related to oxidative metabolism, was higher in the EX than in the EXLA group. These results suggest that lactate can be used in various research fields to promote carbohydrate metabolism.

Dietary oxidized fish oil negatively affected the feed utilization, health status and fillet quality of juvenile Amur sturgeon, A. schrenckii

This study was carried out to explore the effects of dietary oxidized fish oil on growth, feed utilization, health status and fillet quality of juvenile Amur sturgeon (A. schrenckii) (initial mean body weight = 70.0 ± 0.02 g). An 8-week experiment with diets containing 6% fresh fish oil (FFO) or 6% oxidized fish oil (OFO) was conducted. The peroxide values (POV) of fresh and oxidized fish oil were 9.14 and 384.73 meq/kg, respectively. The results indicated that compared to the FFO group, dietary OFO had no significant influence on growth (P > 0.05), but increased feeding rate (FR) and decreased productive protein value (PPV) significantly (P < 0.05). The fish in the OFO group had lower serum high-density lipoprotein cholesterol (HDL-C), albumin (ALB), and the ratio of ALB to globulin (GLOB), and higher serum malonaldehyde (MDA) and superoxide anion free radical (O2−) than those in the FFO group (P < 0.05). OFO induced inflammatory cell infiltration in the liver, and the expressions of hepatic inflammatory cytokines were significantly up regulated in the fish fed with OFO (P < 0.05). The fish in the OFO group showed abnormal yellow skin, and the yellowness value of the dorsal muscle was significantly elevated in comparison with the FFO group (P < 0.05). The contents of muscle protein, lipid, and glycogen were significantly declined by dietary OFO (P < 0.05). Dietary OFO affected the muscle essential amino acid (EAA) composition remarkably, among which the proportions of Ile and Met were reduced while Leu was promoted significantly (P < 0.05). The fish fed with OFO had significantly higher n-6 polyunsaturated fatty acids (PUFA) proportion and n-6 PUFA/n-3 PUFA ratio (P < 0.05) than the fish fed with FFO, but there were no changes in the proportion of saturated (SFA), monounsaturated fatty acid (MUFA) and n-3 PUFA (P > 0.05). The total free amino acid (FAA) was enhanced significantly by dietary OFO, but the delicious amino acid (DAA) proportion was decreased in the muscle of the fish fed with OFO (P < 0.05). In summary, dietary OFO had no significant influence on growth, but decreased feed utilization of Amur sturgeon. Dietary OFO impaired the health status of Amur sturgeon by inducing oxidative stress, lowering serum HDL-C, ALB and causing liver damage. Dietary OFO adversely affected the fillet quality of Amur sturgeon by altering body color, muscle proximate composition, glycogen content, EAA, fatty acid and FAA profiles.

The Validity of Ultrasound Technology in Providing an Indirect Estimate of Muscle Glycogen Concentrations Is Equivocal.

Researchers and practitioners in sports nutrition would greatly benefit from a rapid, portable, and non-invasive technique to measure muscle glycogen, both in the laboratory and field. This explains the interest in MuscleSound®, the first commercial system to use high-frequency ultrasound technology and image analysis from patented cloud-based software to estimate muscle glycogen content from the echogenicity of the ultrasound image. This technique is based largely on muscle water content, which is presumed to act as a proxy for glycogen. Despite the promise of early validation studies, newer studies from independent groups reported discrepant results, with MuscleSound® scores failing to correlate with the glycogen content of biopsy-derived mixed muscle samples or to show the expected changes in muscle glycogen associated with various diet and exercise strategies. The explanation of issues related to the site of assessment do not account for these discrepancies, and there are substantial problems with the premise that the ratio of glycogen to water in the muscle is constant. Although further studies investigating this technique are warranted, current evidence that MuscleSound® technology can provide valid and actionable information around muscle glycogen stores is at best equivocal.

Augmented muscle glycogen utilization following a single session of sprint training in hypoxia.

This study determined the effect of a single session of sprint interval training in hypoxia on muscle glycogen content among athletes. Ten male college track and field sprinters (mean ± standard error of the mean: age, 21.1 ± 0.2years; height, 177 ± 2cm; body weight, 67 ± 2kg) performed two exercise trials under either hypoxia [HYPO; fraction of inspired oxygen (FiO2), 14.5%] or normoxia (NOR: FiO2, 20.9%). The exercise consisted of 3 × 30s maximal cycle sprints with 8-min rest periods between sets. Before and immediately after the exercise, the muscle glycogen content was measured using carbon magnetic resonance spectroscopy in vastus lateralis and vastus intermedius muscles. Moreover, power output, blood lactate concentrations, metabolic responses (respiratory oxygen uptake and carbon dioxide output), and muscle oxygenation were evaluated. Exercise significantly decreased muscle glycogen content in both trials (interaction, P = 0.03; main effect for time, P < 0.01). Relative changes in muscle glycogen content following exercise were significantly higher in the HYPO trial (- 43.5 ± 0.4%) than in the NOR trial (- 34.0 ± 0.3%; P < 0.01). The mean power output did not significantly differ between the two trials (P = 0.80). The blood lactate concentration after exercise was not significantly different between trials (P = 0.31). A single session of sprint interval training (3 × 30s sprints) in hypoxia caused a greater decrease in muscle glycogen content compared with the same exercise under normoxia without interfering with the power output.

FOSL2 Is Involved in the Regulation of Glycogen Content in Chicken Breast Muscle Tissue.

The glycogen content in muscle of livestock and poultry animals affects the homeostasis of their body, growth performance, and meat quality after slaughter. FOS-like 2, AP-1 transcription factor subunit (FOSL2) was identified as a candidate gene related to muscle glycogen (MG) content in chicken in our previous study, but the role of FOSL2 in the regulation of MG content remains to be elucidated. Differential gene expression analysis and weighted gene coexpression network analysis (WGCNA) were performed on differentially expressed genes (DEGs) in breast muscle tissues from the high-MG-content (HMG) group and low-MG-content (LMG) group of Jingxing yellow chickens. Analysis of the 1,171 DEGs (LMG vs. HMG) identified, besides FOSL2, some additional genes related to MG metabolism pathway, namely PRKAG3, CEBPB, FOXO1, AMPK, and PIK3CB. Additionally, WGCNA revealed that FOSL2, CEBPB, MAP3K14, SLC2A14, PPP2CA, SLC38A2, PPP2R5E, and other genes related to the classical glycogen metabolism in the same coexpressed module are associated with MG content. Also, besides finding that FOSL2 expression is negatively correlated with MG content, a possible interaction between FOSL2 and CEBPB was predicted using the STRING (Search Tool for the Retrieval of Interacting Genes) database. Furthermore, we investigated the effects of lentiviral overexpression of FOSL2 on the regulation of the glycogen content in vitro, and the result indicated that FOSL2 decreases the glycogen content in DF1 cells. Collectively, our results confirm that FOSL2 has a key role in the regulation of the MG content in chicken. This finding is helpful to understand the mechanism of MG metabolism regulation in chicken and provides a new perspective for the production of high-quality broiler and the development of a comprehensive nutritional control strategy.

Effect of ginger extract ingestion on skeletal muscle glycogen contents and endurance exercise in male rats

[Purpose]Skeletal muscle glycogen is a determinant of endurance capacity for some athletes. Ginger is well known to possess nutritional effects, such as anti-diabetic effects. We hypothesized that ginger extract (GE) ingestion increases skeletal muscle glycogen by enhancing fat oxidation. Thus, we investigated the effect of GE ingestion on exercise capacity, skeletal muscle glycogen, and certain blood metabolites in exercised rats. [Methods]First, we evaluated the influence of GE ingestion on body weight and elevation of exercise performance in rats fed with different volumes of GE. Next, we measured the skeletal muscle glycogen content and free fatty acid (FFA) levels in GE-fed rats. Finally, we demonstrated that GE ingestion contributes to endurance capacity during intermittent exercise to exhaustion. [Results]We confirmed that GE ingestion increased exercise performance (p<0.05) and elevated the skeletal muscle glycogen content compared to the non-GE-fed (CE, control exercise) group before exercise (Soleus: p<0.01, Plantaris: p<0.01, Gastrocnemius: p<0.05). Blood FFA levels in the GE group were significantly higher than those in the CE group after exercise (p<0.05). Moreover, we demonstrated that exercise capacity was maintained in the CE group during intermittent exercise (p<0.05). [Conclusion]These findings indicate that GE ingestion increases skeletal muscle glycogen content and exercise performance through the upregulation of fat oxidation.

Environmental modulators of diluted bitumen effects in juvenile pink salmon (Oncorhynchus gorbuscha)

Recent and potential expansions in the transportation of diluted bitumen (dilbit) through marine terminals in coastal regions of British Columbia require the examination of potential risks to estuarine species such as Pacific salmon. The estuarine habitat of out-migrated pink salmon (Oncorhynchus gorbuscha) exhibits dynamic temperature and salinity regimes, possibly modifying dilbit exposure, bioavailability and/or its effects. To examine dilbit toxicity and its modification by environmental stressors, juvenile pinks were subchronically exposed for 3 months to the water-accommodated fraction (WAF) of Cold Lake Blend dilbit (winter) in seawater at three salinities (7, 14, and 28‰ [temperature 12.5 °C]) and three temperatures (8.5, 12.5, and 16.5 °C [salinity of 28‰]). Temperature and salinity alone did not affect any measured endpoints in control fish. Dilbit exposure induced higher mortality at high (16.5 °C) and low temperatures (8.5 °C) as well as at higher salinity (28‰) in fish exposed to the highest dilution of WAF [total polycyclic aromatic compounds (TPAC) = 128.9 μg/L]. A concentration-dependent reduction of growth was evident in fish exposed to the medium (TPAC = 97.3 μg/L) and high dilution of WAF at higher temperatures (12.5 and 16.5 °C) and high salinity (28‰). At 28‰, swimming performance (Uburst) was decreased in fish exposed to the highest concentration of dilbit at all 3 temperatures. Gill Na+-K+-ATPase activity, white muscle lactate, glycogen, and triglyceride concentrations were altered by dilbit exposure and modified by temperature and salinity. In addition, gene expression associated with phase I biotransformation, energy metabolism, mitochondrial activity, and inflammation showed significant upregulation with exposure and temperature stress. Dilbit exposure at PAC concentrations in the ppb range, affected pink salmon at the molecular, biochemical, and whole organism level; effects that were exacerbated by environmental temperature and salinity.

Neither Peristaltic Pulse Dynamic Compressions nor Heat Therapy Accelerate Glycogen Resynthesis after Intermittent Running.

To investigate the effects of a single session of either peristaltic pulse dynamic leg compressions (PPDC) or local heat therapy (HT) after prolonged intermittent shuttle running on skeletal muscle glycogen content, muscle function, and the expression of factors involved in skeletal muscle remodeling. Twenty-six trained individuals were randomly allocated to either a PPDC (n = 13) or a HT (n = 13) group. After completing a 90-min session of intermittent shuttle running, participants consumed 0.3 g·kg-1 protein plus 1.0 g·kg-1 carbohydrate and received either PPDC or HT for 60 min in one randomly selected leg, while the opposite leg served as control. Muscle biopsies from both legs were obtained before and after exposure to the treatments. Muscle function and soreness were also evaluated before, immediately after, and 24 h after the exercise bout. The changes in glycogen content were similar (P > 0.05) between the thigh exposed to PPDC and the control thigh ~90 min (Control: 14.9 ± 34.3 vs PPDC: 29.6 ± 34 mmol·kg-1 wet wt) and ~210 min (Control: 45.8 ± 40.7 vs PPDC: 52 ± 25.3 mmol·kg-1 wet wt) after the treatment. There were also no differences in the change in glycogen content between thighs ~90 min (Control: 35.9 ± 26.1 vs HT: 38.7 ± 21.3 mmol·kg-1 wet wt) and ~210 min (Control: 61.4 ± 50.6 vs HT: 63.4 ± 17.5 mmol·kg-1 wet wt) after local HT. The changes in peak torque and fatigue resistance of the knee extensors, muscle soreness, and the mRNA expression and protein abundance of select factors were also similar (P > 0.05) in both thighs, irrespective of the treatment. A single 1-h session of either PPDC or local HT does not accelerate glycogen resynthesis and the recovery of muscle function after prolonged intermittent shuttle running.

A proprietary herbal drug Young Yum Pill ameliorates chronic fatigue syndrome in mice

BackgroundChronic fatigue syndrome (CFS) is a complex disease with few effective and safe therapies. Young Yum Pill (YYP), a proprietary herbal drug, has been used to relieve CFS-like symptoms. The pharmacological basis of this application of YYP is unknown. PurposeThis study aimed to investigate the pharmacological effects and mechanisms of action of YYP in a mouse model of CFS. Study design and methodsA food restriction and exhaustive swimming-induced mouse CFS model was used to evaluate the effects of YYP. Lymphocyte proliferation was assessed by MTT assays. T-lymphocyte subsets were analyzed by flow cytometry. Serum biochemical parameters were determined using commercial kits. Protein levels were measured by immunoblotting. ResultsIntragastric administration of YYP (2.85, 5.70, 11.40 g/kg) daily for 21 consecutive days significantly prolonged swimming time and diminished body weight loss of CFS mice. Mechanistic investigations revealed that YYP increased thymus and spleen indices of CFS mice, enhanced proliferation of lipopolysaccharide- or concanavalin A-stimulated spleen lymphocytes, and increased CD3+CD4+ and CD3+CD8+ T-cells in the spleen. YYP increased glycogen content in gastrocnemius muscle and liver, and lowered levels of triglyceride, lactic acid and urea nitrogen in sera of CFS mice. YYP suppressed the elevation of serum level of malondialdehyde, the increase of activities of lactic dehydrogenase and creatine phosphokinase, and the decrease of activity of the serum antioxidant enzyme superoxide dismutase in CFS mice. Moreover, YYP upregulated protein level of activated AMPK in gastrocnemius muscle and liver of CFS mice. ConclusionsYYP ameliorates CFS by reversing metabolic changes, reducing oxidative damage, and improving some immune function parameters in mice. This study provides pharmacological justifications for the use of YYP in treating fatigue, including CFS.

The Effect of Lactobacillus plantarum CQPC02 on Fatigue and Biochemical Oxidation Levels in a Mouse Model of Physical Exhaustion.

Chinese Sichuan pickle is a fermented food rich in microorganisms. Microorganisms have the potential to become an important new form of potent future therapeutic capable of treating human disease. Selecting vitamin C as a positive control, a lactic acid bacteria (Lactobacillus plantarum CQPC02, LP-CQPC02) isolated from Sichuan pickle was given to mice over 4 weeks to investigate the effect of CQPC02 on fatigue levels and biochemical oxidation phenomena in exercise-exhausted Institute of Cancer Research (ICR) mice. The fatigue model was established by forced swimming of mice, the levels of hepatic glycogen, skeletal muscle glycogen, lactic acid, blood urea nitrogen and free fatty acid were measured by physicochemical methods, serum serum creatine kinase (CK), aspartate aminotransferase (AST) and alanine aminotransferase (ALT), superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) levels were measured by kits, the histopathological changes in the livers of mice were observed by H&E slicing, and the mRNA changes in the livers and skeletal muscles were observed by quantitative polymerase chain reaction (qPCR). Both vitamin C and LP-CQPC02 increased swimming exhaustion time. The concentration of LP-CQPC02 and exhaustion time were positively correlated. LP-CQPC02 also increased liver glycogen, skeletal muscle glycogen and free fatty acid content in mice and reduced lactic acid and blood urea nitrogen content in a dose-dependent manner. As walnut albumin antioxidant peptide concentration increased, levels of mouse CK, AST, and AST gradually decreased. LP-CQPC02 increased SOD and CAT levels and decreased MDA levels in a dose-dependent fashion. LP-CQPC02 up-regulated expression of mRNA encoding copper/zinc-superoxide dismutase (Cu/Zn-SOD), manganese-superoxide dismutase (Mn-SOD), and CAT in swimming exhaustion mouse liver tissue. LP-CQPC02 also up-regulated alanine/serine/cysteine/threonine transporter 1 (ASCT1) expression while down-regulating syncytin-1, inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNF-α) expression in swimming exhaustion mouse skeletal muscle. Overall, LP-CQPC02 had a clear anti-fatigue and anti-oxidation effect. This suggests that LP-CQPC02 can be developed as a microbiological therapeutic agent.

Evaluation of anti-fatigue property of Porphyridium cruentum in mice

Purpose: To evaluate the potential effects of Porphyridium cruentum (PC) on fatigue induced by forced swimming test in mice.&#x0D; Methods: Mice were randomly divided into normal control group (NC, i.e., untreated non-swimming); model control group (MC, untreated swimming); Spirulina treated group (SP, 800 mg/kg); PC-treated groups (50, 100, and 200 mg/kg), respectively. After intragastric administration for 14 consecutive days, a weight-bearing swimming experiment was conducted for the mice, and the biochemical indicators related to fatigue were examined, including exhaustive swimming time, glucose levels (Glu), hepatic glycogen contents (HG), muscle glycogen contents (MG), glutathione peroxidase activities (GSH-Px), creatine kinase (CK), malondialdehyde (MDA), urea nitrogen levels (SUN), lactate dehydrogenase activities (LDH), lactic acid (LA) as well as superoxide dismutase (SOD).&#x0D; Results: PC significantly prolonged the swimming endurance time compared to MC. After PC treatment, Glu, HG and MG were effectively increased dose-dependently, SUN, LA, LDH and CK levels in serum were significantly reduced. Moreover, PC treatment elevated the bioactivities of two antioxidant enzymes, namely, GSH-Px and SOD, while MDA content decreased when compared to MC group.&#x0D; Conclusion: These results indicate that PC exhibits strong anti-fatigue effect. Thus, PC may be suitable for incorporation in functional food to counter fatigue.

Interactions of dietary carbohydrate and vitamin D3 on growth performance, insulin signaling pathway and glucose metabolism in juvenile abalone Haliotis discus hannai

A 115-day feeding trial was conducted to investigate the effect of dietary carbohydrate and vitamin D3 levels, and their interactions on growth performance, body composition, insulin signaling pathway and glucose metabolism in juvenile abalone Haliotis discus hannai (initial body weight: 2.06 ± 0.01 g). Nine experimental diets in a 3 × 3 two-factor design were formulated with different carbohydrate levels (27.5%, 32% and 36.5%) and vitamin D3 levels (0, 1000 IU/kg and 5000 IU/kg). Results showed that the highest specific growth rate (SGR) of abalone was observed in the treatment with 36.5% of dietary carbohydrate and 1000 IU/kg of vitamin D3. The serum glucose, body crude lipid and muscle glycogen contents of abalone significantly increased with increasing dietary carbohydrate levels (P < 0.05). Diet with 1000 IU/kg of vitamin D3 significantly reduced the serum glucose and body crude lipid content (P < 0.05). Significant interactions between dietary carbohydrate and vitamin D3 were observed in SGR and crude lipid content (P < 0.05). Diet with 36.5% carbohydrate up-regulated the expression of pyruvate kinase, glucose-6-phosphate dehydrogenase (G6PDH), insulin receptor (IR), insulin receptor substrate (IRS), protein kinase B (Akt), glycogen synthase and glycogen phosphorylase (PYG), whereas decreased the phosphoenolpyruvate carboxykinase (PEPCK), glucose-6-phosphatase (G6P) and glycogen synthesis kinase-3β. Diet with 1000 IU/kg of vitamin D3 significantly up-regulated the hexokinase, IR, IRS, Akt and glucose transporter 1 mRNA levels, whereas decreased the G6PDH (P < 0.05). The interaction between dietary carbohydrate and vitamin D3 were significant on PEPCK, G6P, G6PDH and PYG mRNA levels (P < 0.05). In conclusion, dietary carbohydrates and vitamin D3 could affect glucose metabolism by regulating glycolysis, gluconeogenesis and pentose phosphate pathway in abalone. Besides, they triggered the insulin signaling pathway, and further influence glucose transport and glycogen synthesis, which could promote the utilization of carbohydrate in abalone.