Showing 4 results for Skeletal Muscle
Abbas Saremi,
Volume 12, Issue 2 (9-2009)
Abstract
Background: Muscle mass is known to be a significant predictor of bone mineral density (BMD), and myostatin is a negative regulator of muscle growth. The aim of present study was investigate the effects of resistance training on bone mineral density and serum myostatin in healthy young men. Methods and Materials: In this clinical trial thirty young men were assigned to resistance training (n=15) and control (n=15) groups. The training group participated in 6 mounths of progressive whole-body resistance training. Total body fat, lean body mass, total body BMD, femoral neck BMD and L2-L4 spine BMD were determined by Dual-Energy X-ray Absorptiometry (DEXA) before and after 6 mounths of resistance training. Serum level myostatin measured by enzyme immnoassay. Results: Resistance training caused significant increases in chest press (52.36±6.36 vs 62.20±8.96 kg), leg press (135.24±13.77 vs 146.91±17.66 kg), lean body mass (61.00±0.96 vs 62.58±2.08 kg) and femoral neck BMD (1.115±0.078 vs 1.131±0.088 g/cm2), whereas myostatin were decreased (102.91±10.18 vs 94.03±13.93 ng/ml) (P<0.05). Total body BMD and L2-L4 spine BMD did not change with 6 months resistance training. Conclusion: A 6 month resistance training program increases muscle mass, power and improves BMD of the femoral neck in young men, and myostatin inhibition may play an important role in increasing BMD which is induced by resistance training.
Moein Rahimi Sadegh, Amir Rashidlamir, Ali Akbar Haddad Mashhad Rizeh, Mohammad Soukhtanloo,
Volume 20, Issue 12 (3-2018)
Abstract
Abstract
Background: Recent Research has pointed to the involvement of lysyl oxidase (LOX) in the muscle development. Despite the fact, there is currently no direct evidence that lox is involved in the myogenic factors and exercise-induced hypertrophy. Therefore, the purpose of this study was to investigate the effect of lysyl oxidase inhibition on exercise-induced hypertrophy, as well as the gene expression of MyoD1, myogenin, TGF-β and LOX in FHL muscle of wistar rats.
Material and Methods: In this experimental research, 32 male Wister rats with an average weight of 220±15 were divided into four groups: resistance training, normal control, treated control and treated resistance training. Rats performed a resistance training for 8 weeks in which animals climbed a vertical ladder of 1m and inclined at 85° with weights attached to their tails. In order to inhibit lysyl oxidase, treatment group rats received daily injection of intraperitoneal β-aminopropionitrile (120 mg/kg/day). FHL muscle was extracted to measure relative muscle weight, as well as genes expression of MyoD1, myogenin, TGF-β and LOX by real time-PCR.
Results: Relative weight of FHL muscle was decreased significantly in the treated groups with BAPN, compared with normal groups (p<0.05). Lysyl oxidase showed a significant increase compared to the normal control group following a resistance training (p<0.05). LOX gene expression in treatment groups showed a significant increase compared to normal control group (p<0.05). TGF-β gene expression in BAPN-treated groups significantly was increased (p<0.05) and Myogenin in treatment groups showed a significant decrease compared to normal control groups (p<0.05). The expression of MyoD1 gene in treatment groups was only decreased significantly in the treated control groups compared to normal control groups (p<0.05).
Conclusion: Results showed that inhibiting the lysine oxidase enzyme could affect the genes involved in hypertrophy and reduce the hypertrophy induced by resistance training.
Mahdi Bayati, Reza Gharakhanlou, Maryam Nikkhah, Sadegh Amani Shalamzari,
Volume 21, Issue 3 (6-2018)
Abstract
Background and Aim: Low-volume, high-intensity interval training (HIT) increase skeletal muscle aerobic capacity, yet little is known about the potential mechanisms in improvement of this adaptability. The purpose of present study was to examine the effect of four weeks of HIT on peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) and vascular endothelial growth factor (VEGF) protein contents in skeletal muscle of active men.
Materials and Methods: Eight active male students voluntarily and purposefully participated in this study. One week before the experiment started; subjects were familiar with protocol of research. Needle biopsy samples vastus lateralis were obtained 48 h before training and 72 h after the final training session. HIT protocol consisted of 11-15 bouts of 1 min cycling at ∼85-90% of reserve heart rate separated by 1 min of active recovery between each, 3 sessions per week for 4 weeks. Variables were measured by ELISA. All data were analyzed using paired t-test and at the level of significance of p ≤ 0.05.
Findings: Results of study showed the four weeks of HIT lead to significant increase in PGC-1α and VEGF (p < 0.001).
Conclusion: Our findings suggest that activation of VEGF from PGC-1α pathway is part of cellular-molecular mechanisms of high-intensity interval training. So, probably angiogenesis in skeletal muscle is one of the most important factors in improving of aerobic performance, which requires more studies. |
Mis Mahnaz Najafi, Mohammad Reza Asad, Mostafa Rahimi, Rahman Souri, Ali Ahvar,
Volume 21, Issue 4 (8-2018)
Abstract
Background and Aim: The aim of study was to investigate the effect of 8 weeks of moderate-intensity continuous training (MICT) and high intensity interval training (HIIT) on the GLUT4 gene expression in skeletal muscle of obese male rats.
Materials and Methods: Twenty-eight male Wistar rats with 150 ± 25 grams body weight were divided into base control (n = 6), obese control (n = 6), MICT (n = 8), and (n = 8) HIIT groups as study sample. At the beginning of the study, base control group rats were sacrificed. In other groups, rats underwent high fat regime diet for 8 weeks. After one week of familiarization, rats in training groups run on treadmill for 8 weeks and 5 days per week. Forty-eight hours after the last session, the rats were scarified and gastrocnemius muscle tissue sample were removed. GLUT4 gene expression was measured by Real-Time PCR methods.
Findings: Results indicated that high fat diet for 8 weeks significantly increased rats body weight (p= 0.001), whereas both of MICT and HIIT training significantly decreased body weight (p= 0.001). Moreover, the MICT and HIIT had significant increase in GLUT4 gene expression in gastrocnemius muscle of obese rats (p = 0.001). Although, there were no differences between two experimental groups (p = 0.99).
Conclusion: According to the results, the MICT and HIIT increase gene expression of GLUT4 in mixed muscle fibers in obese rats. |
