Brain-derived neurotrophic factor, insulin-like growth factor 1 and its binding protein responses to a session of endurance exercises in healthy elderly men

This study investigated the effect of endurance activity on brain-derived neurotrophic factor [BDNF], insulin-like growth factor 1 [IGF-1] and its binding protein 3 [IGFBP-3] in elderly healthy individuals. Eleven healthy old males [mean age of 68 +/- 2.31 years old, height of 177 +/- 3.1 cm and weight of 79 +/- 1.5 kg] were studied. Seventy two hours after maximal oxygen consumption [VO[2] max] evaluation, the participants performed an endurance activity at the intensity of 70% of their VO[2] max. Three blood samples were collected from the antecubital vein before, immediately and 30 minutes after the activity. The data were analyzed by repeated measures [P

[Effects of various time courses of endurance training on antioxidant enzymes activity in rat Serum]

Due to the importance of antioxidative system and its effective intervention on cascade reactions of free radicals, this study was run to determine the alterations in antioxidant enzymes activity Superoxide dismutase [SOD], Catalase [CAT], and Glutathione peroxidase [GPX] after various time courses of endurance training in rat serum. In this study, 62 male Wistar rats were selected randomly and were divided into 3 control [n[1]=10, n[2]=10, n[3]=11] and 3 experimental [n[1]=10, n[2]=10, n[3]=11] groups. Experimental rats trained for 6, 9 and 12 weeks, running for 5 days/week on treadmill with initial speed of 10 m/min for 10 minute, which was gradually incrased to reach the ultimate speed of 25 m/min for 60 minute. For control groups, the protocol was walking on treadmill with the speed of 10 m/min for 3 days/week. After each course [6, 9 and 12 w], rats were anesthetized and serum samples were collected. Determination of antioxidant enzymes activity was done using Cayman chemical company kits [MI, USA], using enzymatic color assay method. The results were analyzed by t - test [alpha=0.05]. The results of this study showed that 6, 9 and 12 weeks of endurance training had no significant effects on Serum SOD and GPX activity, but 9 weeks of endurance training increased the activity of CAT significantly [CAT activity in experimental group was 24.09 +/- 2.43 U/mL while it was 18.76 +/- 3.81 U/m in the control group, p

[Effect of short term L-carnitine supplementation on endurance performance and markers of cellular damage in acute hypoxia]

Exercise in high altitude and hypoxia decreases aerobic power and increases oxidative stress and lactic acid. Due to the metabolic and antioxidant properties of L-Carnitine, the purpose of this study was to investigate the effect of short-term L-Carnitine supplementation on endurance performance and cell damage in acute hypoxia. For this purpose, 16 active men after VO2max measurement in normoxia were divided into 2 groups of supplement and placebo. Supplement group received L-Carnitine and placebo group received placebo [sugar] for 10 days [3 g every day]. After eight days of supplementation period, VO2max in hypoxia condition was determined as well as normoxia. Then 1 day after supplementation, individuals participated in submaximal test [60%VO2max for 1 hour]. Blood samples were taken before, immediately after and 1 hour after recovery for determining lactic acid, lactate dehydrogenase [LDH], creatin kinase [CK] and malondialdehyde [MDA]. The result showed that short-term supplementation with L-Carnitine had no effect on VO2max [p=0.83], respiratory exchange ratio [RER] [p=0.314] and lactic acid, but it caused significant decrease in LDH [p=0.001], CH [p=0.001] and MDA [p=0.001] after submaximal activity. It can be concluded that short-term supplementation of L-Carnitine doesn't influence VO2max and lactate, but it may decrease cell damage.

[Effect of short term supplementation with L-carnitin and coenzyme Q10 on aerobic and anaerobic exercise performance in sedentary college men]

In skeletal muscle, carnitine plays an essential role in translocation of long-chain fatty-acids for subsequent beta-oxidation; in addition, coenzyme Q10 [ubiquinone, CoQ10] is a component of the mitochondrial electron transport chain and also an important antioxidant. Despite abundant literature describing the basic mechanism of L-carnitine and CoQ10 metabolism, there remains some uncertainty regarding the effect of oral L-carnitine and CoQ10 supplementation. The aim of this study was to investigate effect of CoQ10 and L-carnitine supplementation on aerobic and anaerobic exercise performance in healthy inactive collegiate men. In a randomized double-blind placebo-controlled trial, 40 subjects [age: 23.01 +/- 2.97 y, weight: 72.9 +/- 11.71 kg and height: 176.80 +/- 5.36 cm] participated in two test sessions separated by 10 days. Subjects were randomly allocated into parallel groups to receive either CoQ10 [3 mg/kg/day], L-carnitin [30 mg/kg/day], both of them, or placebo, for 10 days. A 30-second Wingate anaerobic capacity test for determination of fatigue index [FI], and a maximal cardiopulmonary graded exercise test [modified Bruce protocol], for direct determination of VO2max by gas analyzer, were performed on the day before and after supplementation period. Data was analyzed using repeated measures ANOVA and paired sample T test. Results showed that co-supplementation with L-carnitine and CoQ10 had a significant incremental effect on VO2max [p< 0.05]. In the L-carnitine group, VO2max showed a tendency to increase but it was not significant [p=0.096]. FI decreased by 7.7% with L-carnitine + CoQ10, compared with 4.9% increase in placebo group; however this difference was not statistically significant [p=0.099]. Only supplementation with L-carnitine could significantly improve the fatigue index [p<0.05]. Short term co-supplementation with L-carnitine and CoQ10 may improve aerobic and anaerobic exercise performance in inactive collegiate men

[Effect of various time courses of endurance training on alterations of antioxidant enzymes activity in rat liver tissue]

Anti oxidative enzymes activity is an important issue in oxidative stress. Most previous researches have dealt with the effect of brief and anaerobic exercise on these enzymes; the purpose of this study was to determine the alterations of antioxidant enzymes viz. superoxide desmutase, catalase and glutathione [SOD, CAT, and GPX] activity after endurance training in rat liver tissue. In this experimental study, 62 male Wistar rats were selected randomly and divided into 3 control and 3 experimental groups. Experimental rats trained for 6, 9 and 12 weeks, 5 days/week running on treadmill with initial speed of 10 m/min for 10 minute to the ultimate speed of 25 m/min for 60 minute. For control groups the protocol was walking on treadmill with 10 m/min speed for 3 days/ week. After each course [6, 9, 12 wk.], rats were anesthetized and samples taken from the livers of all animals in the study. Determination of antioxidant enzymes activity was done with enzymatic color assay method. The results showed that 6, 9 and 12 weeks of endurance training have no significant effect on GPX activity. Also, 6 and 9 weeks of endurance training did not alter the activity of SOD and CAT in liver tissue, but, 12 weeks of endurance training decreased SOD and CAT activity significantly, [CAT activity in experimental group was 23.11 +/- 7.27 U/mL and in control group it was 31.43 +/- 7.21 U/mL; SOD activity in experimental group was 47.70 +/- 0.56 U/mL and in control group it was 48.20 +/- 0.48 U/mL, [P<0.05]]. Results of this study reveal that participating in 9 weeks of moderate exercise does not have detectable effects on the anti oxidative system, but when the exercise continues until 12 weeks, it decreases the SOD and CAT enzyme activity