meysam gholamali

One the major reason of the age-related muscular atrophy, Sarcopenia, is neurogenic atrophy. Despite this issue, the effects of some pathway which have probability effect, such as: kind of training methods, especially high interval intensive training, on the main factors of the neurogenic cascades is not yet clear. Therefore, the aim of this study was to investigate the effects of high interval intensive training period on the expression of the HDAC4, HDAC5, Dch2 and Myogenin gens in the plantaris muscle of the aged male Wistar rats. 28 male Wistar rats randomly assigned in to four groups (N=7, adult control, N=7, adult training, N=7, aged control, N=7, aged training). The training group performed HIT 5 times per week for 6 weeks. 48 hours after the end of the last session of training with control group were anesthetized and sacrificed. Then the plantaris muscle was removed. Real time PCR method was used to determine the gene expression levels of HDAC4, HDAC5, Dch2 and Myogenin. For the statical analyses two-way ANOVA and Tukey were used. The statical significant assumed P≤0.05. The results of this study have been shown that HDAC4, HDAC5 and Myogenin significantly decreased. The amount of the Dch2 increased significantly compared to young control group. According to the results of this study, it seems high interval intensive training suppress the neurogenic atrophy   in the orders adult.

Studies reported conflicting results about the relationship between anthropometric factors, respiratory exchange Ratio, energy expenditure and VO2 max. Therefore the aim of this study was to investigate the relationship between anthropometric factors, respiratory exchange ratio and energy expenditure with VO2 max in sedentary men. Thirty one sedentary healthy men (23.67±2.45 years old age, BMI=22.49±1.58 kg/m2) volunteered for participation this study. After the measurement of anthropometric factors, subjects performed an acute endurance exercise on the ergometer for determination of VO2 max. Subjects performed major protocol, one hour cycling on ergometer via 70% VO2 max for the determination of the respiratory exchange ratio and the rate of energy expenditure, 72 hours later. The results of this study showed that there is not any significant relationship between VO2 max and anthropometric factors, respiratory exchange ratio and energy expenditure. Also, regression analysis indicated that all these variables cannot predicate the VO2 max. According to the results of this study anthropometric factors, respiratory exchange ratio and energy expenditure are not strong predictors of VO2 max in sedentary young men.

Endurance training increases capillary density of skeletal muscle, but the molecular mechanism of this process is not yet clear. Therefore, the purpose of this study was to investigate the effect of acute sub maximal endurance exercise on serum levels of vascular endothelial growth factor (VEGF) and matrix metaloproteinases 2 and 9 (MMP-2 and MMP-9) in sedentary men. Twelve healthy men (22.37±2.30 years, BMI=23.16± 2.61 kg/m2) participated in this study. Subjects exercised for 1h at 70% of VO2 max, 3 days after the VO2 max determination. Antecubital vein blood was collected at rest, immediately and 2h after the exercise. Serum VEGF, MMP-2 and MMP-9 were measured by ELISA methods. Serum levels of VEGF and MMP-2 decreased immediately after the exercise. 2 hours after the exercise, serum levels of VEGF remained at a lower level but serum MMP-2 returned to its basal level. Also, serum levels of MMP-9 did not change significantly in response to exercise. Acute sub-maximal endurance exercise decreased the main factors involved in development of capillary density in sedentary men. This might to due to the fact that, sub maximal exercise could not provide the two main stimulating factors of angiogenesis, i.e. Shear stress and hypoxia. It could also be explained by the fact that the mechanism of development of capillary network following regular endurance training is different from that following an acute exercise.

Concomitant with aging the amount of myostatin، as most important negative regulator of muscular mass، increases. Presumably، this issue has correlation with decrement of muscular mass and muscular strength. On the other hand، the response of this protein to resistance exercise in these people is not perfectly clear. Therefore، the aim of this study was to investigative the relationship between plasma myostatin with muscular volume and muscular maximal strength and it’s response to acute resistance exercise in elderly. 12 healthy old men participated in this study (60-75 years old age). 72 hours after the determination of muscular volume and muscular maximal strength، subjects participated in acute resistance exercise. Three blood samples were collected immediately before، and 4 hours after the exercise from antecubital vein. Plasma myostatin measured by ELISA methods. There was a significant correlation between muscular mass and muscular strength with plasma myostatin in older men (P<0. 05). Immediately and 4 hours after the resistance exercise the amount of myostatin significantly decreased (P<0. 05). Furthermore، the amount of myostatin 4 hours after the exercise showed a non-significant decrease as compared to immediately after the exercise. Our findings indicate that the increment of myostatin is along with decrement of muscular mass and strength in elderly. On the other hand، resistance exercise can decrease the plasma myostatin. This may decrease the prevalence of age-related muscular atrophy (sarcopenia) in the elderly

Endurance training increases capillary density in skeletal and heart muscles. But the molecular mechanism of these processes is not yet clear. Substantial evidence indicates that the vascular endothelial growth factor (VEGF, angiogenic factor) and endostatin (antiangiogenic factor) might play key role in this process. Therefore, we investigated the effect of endurance training on serum levels of VEFG and endostatin in wistar rat. The study was performed in 20 male wistar rats, which were aged between 64 ± 6 days. All rats were subdivided into two groups randomly: endurance training group (n = 10) and sedentary group (n = 10). Therefore, the training group received 8 weeks of treadmill endurance training. At the end of endurance training program, the rats were anesthetized with halothane, and then blood sample was drawn from the descending aorta for measurement of serum levels of VEGF and endostatin. Serum levels of VEGF and endostatin was measured by ELISA method. Results of the study showed that endurance training increased serum levels of VEGF and decreased endostatin significantly. Furthermore, with adaptation to endurance training VEGF/endostatin ratio increased significantly. Also, VEGF has not significant correlation with endostatin. These finding suggested that with adaptation to endurance training the balance between angiogenic and angiostatic factor switched to angiogenic factor. These finding may provide new insight into the mechanisms relating to capillary density increment in response of endurance training.