Effects of intense exercise on biochemical and histological changes in rat liver and pancreas.

Background: Exercise has various effects on hepatic and pancreatic function. There is little information available for effects of exercise on histopathological changes in the liver and pancreas. Objective: Investigate the effect of intensive exercise on blood biochemical changes and histopathology in rat liver and pancreas. Materials and methods: Male Sprague-Dawley rats were randomly divided into five groups: 1 (normal control): no exercise, 2 (exercise 75% VO2max): running on treadmill at 75% VO2max and sacrificed immediately after exercise, 3 (exercise 75% VO2max+6 hours): running on treadmill at 75% VO2max and sacrificed at six hours after exercise, 4 (exercise 90% VO2max): running on treadmill at 90% VO2max and immediately sacrificed after exercise, 5 (exercise 90% VO2max+6 hours): running on treadmill at 90% VO2max and sacrificed at six hours after exercise. Samples of blood, liver and pancreas were collected at the end of each experiment. Results: The levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) increased significantly in group 2 and 4, compared with normal control. Serum total bilirubin (TB) and enzyme lipase increased significantly in group 4 compared with normal control. In all group of exercise, liver histopathology showed hepatocyte edema and necroinflammation, and pancreas showed congestion and edema. Conclusion: High-intensity exercise at 75% and 90% VO2max caused an increase of biochemical parametes in liver and pancreas. The levels of exercise also caused histopathology changes in the liver and pancreas.

Ginseng supplementation does not change lactate threshold and physical performances in physically active Thai men.

BACKGROUND: Ginseng has been one of the most popular herbs said to improve human exercise performance. Unclear and anecdotal information is known about the effect of ginseng on lactate threshold and aerobic performance in humans. OBJECTIVE: The purpose of the present study was to investigate the effect of ginseng supplementation on lactate threshold in physically active young men. MATERIAL AND METHOD: Sixty men from the Naval Medical Corps, Royal Thai Navy, aged 17- 22 years old, were randomized into either the ginseng (n = 30) or placebo (n = 30) group. The ginseng group took 3 grams of 100% ginseng orally, while the placebo group took an equal amount of lactose powder each day, for 8 weeks. Blood lactic acid levels for determination of lactate threshold (LT) were measured during an incremental cycle ergometer work. LT exercise performance, and heart rate (HR) responses to exercise were determined at baseline and after 8 weeks of ginseng and placebo consumption. Substrate oxidation rates during steady state exercise were assessed upon study completion. Selected markers for liver and kidney functions, including serum aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, and creatinine were monitored for possible side effects of ginseng. RESULTS: L T before and after 8 weeks of supplementation in the ginseng group (164.5 +/- 32.8 and 170.9 +/- 26.4 watts), and in the placebo group (163.7 + 25.1 and 163.7 + 17.3 watts) were not different (p = 0.448). Both groups had a similar pattern of exercise heart rate (p = 0.918), total exercise time (p = 0.241), and peak power output (p = 0.411). After 8 weeks, the magnitude of difference between ginseng and placebo groups on oxidation rates of fat (3.82 +/- 10.0 cal. kg(-1). min(-1), p = 0.704) or carbohydrate (4.36 +/- 12.6 cal. kg(-1). min(-1), p = 0.731) was not statistically significant. There were no abnormal changes of markers of liver and renal functions after ginseng administration. CONCLUSION: Daily administration of 3 g of ginseng for an 8-week period did not improve LT nor did it affect physical performances. Therefore, ginseng supplementation did not exert an ergogenic property on aerobic fitness enhancement in well-fit individuals.

Effects of N-acetylcysteine on oxidative stress in rats with non-alcoholic steatohepatitis.

OBJECTIVE: Prove the attenuated effects of N-acetylcysteine (NAC) on oxidative stress in rats with nonalcoholic steatohepatitis (NASH). MATERIAL AND METHOD: Male Sprague-Dawley rats were randomly divided into five groups. Group I (normal control) was fed regular dry rat chow (RC) for 6 weeks. Group 2 (NASH) was fed 100% fat diet for 6 weeks. Group 3-5 were fed 100% fat diet for 6 weeks, and then switched to RC alone (NASH + diet ; group 3), to RC + 20 mg/kg/day of NAC orally (NASH + diet + NAC20; group 4) or to RC + 500 mg/kg/day of NAC orally (NASH + diet + NAC500; group 5) for 4 weeks, respectively. They were sacrificed to collect blood and liver samples at the end of the present study. RESULTS: Levels of total glutathione (GSH), serum cholesterol, and hepatic malondialdehyde (MDA) were increased significantly in the NASH group compared with normal control. Liver histopathology from group 2 showed moderate to severe macrovesicular steatosis, hepatocyte ballooning, and necroinflammation. Treatment with diet or diet plus NAC reduced the levels of GSH, cholesterol, and hepatic MDA back to normal. Liver sections from group 3-5 showed a decrease in fat deposition and necroinflammation in hepatocytes. However, no differences on all variables existed between diet alone and diet plus NAC groups. CONCLUSION: Our data indicate that diet or diet plus NAC treatment could attenuate oxidative stress and improve liver histopathology of NASH. However the addition of NAC is not better than diet treatment alone.