جستجوی مقالات مرتبط با کلیدواژه « sirt1 » در نشریات گروه « پزشکی »

Atrophy of the skeletal system caused by spinal cord injury (SCI) can cause secondary systemic metabolic dysfunction, such as glucose intolerance, type 2 diabetes, and insulin resistance. On the other hand, Sirtun1 (SIRT1) and Peroxisome Proliferator-Activated Receptor-Gamma Coactivator-1alpha (PGC-1α) are known factors and related proteins involved in skeletal muscle atrophy. Therefore, the present study aimed to investigate the effect of aerobic training with resveratrol consumption on SIRT1 and PGC-1α levels in the gastrocnemius muscles of rats after spinal cord injury.

36 male Wistar rats aged eight weeks were randomly placed in 4 groups including control, resveratrol, training, and resveratrol+training (each group n=9). After anesthesia, an incision was made in the midline of the back and over the vertebral ridges. The muscles and lamina of the T9 vertebra were removed without damaging the dura mater, Spinal cord injury was caused by dropping a ten-gram weight from a height of 25 mm on the spinal cord in the T10 segment. After confirmation of SCI, a Resveratrol supplement with a dose of 10 mg/kg was injected intraperitoneally and daily (every morning for 4 weeks), and the rats of other groups were injected with the same amount of saline. The aerobic training was carried out with the help of the weight support system for 4 weeks, 5 sessions per week, each session was 58 minutes and the intensity was 20 m/min. 48 hours after the last training session, the gastrocnemius muscle of right leg of all rats was removed. The SIRT1 and PGC-1α levels in the gastrocnemius muscle were measured by the ELISA method. To analyze the data, one-way analysis of variance and LSD post hoc tests were used at the significance level of P<0.05.

SIRT1 levels in the gastrocnemius muscle of resveratrol and resveratrol+training groups were significantly higher than the control group (P-value respectively 0.023 and 0.007), but despite the increase in the level of this index in the training group compared to the control group, no significant difference was observed (P=0.399). SIRT1 levels in gastrocnemius muscle of resveratrol+training groups were significantly higher than training group (P=0.038). PGC-1α levels in gastrocnemius muscle of training and resveratrol+ training groups were significantly higher than control group (P-value respectively 0.024 and 0.007), but despite the increase in the level of this index in the resveratrol group compared to the control group, no significant difference was observed (P=0.449). PGC-1α levels in gastrocnemius muscle of resveratrol+training groups were significantly higher than reveratrol group (P=0.023).

These results show the positive effect of resveratrol consumption, on SIRT1 level, as well as aerobic exercise on PGC-1α level of the biceps muscle in rats with SCI. It has been pointed out that the increase in SIRT1 expression and the subsequent increase in PGC-1α leads to an increase in the number of myonuclei, which improves the recovery process after injury and plays an active role in muscle hypertrophy by upregulating and reducing catabolic processes. herefore, it appears that a combination of aerobic training and resveratrol supplementation can mitigate muscle atrophy caused by spinal cord injury in muscles below the level of injury by influencing the levels of muscle SIRT1 and PGC-1α

Non- alcoholic fatty liver is a disease that will lead to liver cirrhosis if not treated. Curcumin is the active substance of the rhizome of the turmeric plant, which has antioxidant, anti- inflammatory, antimicrobial, etc. properties. In the present study, the effects of curcumin analog on the expression of SIRT1 and FAS genes and the accumulation of triglycerides in fatty HepG2 cells (fatty liver model) have been investigated.

In this experimental study, after cultivating HepG2 cells in the right medium and conditions, the MTT test is used to choose the right dose for curcumin and it’s analog. After oiling the cells and treating them with the desired compounds, RNA was extracted and cDNA was made. Then, in order to investigate the effect of curcumin and its analog on the expression of SIRT1 and FAS genes, Real- Time PCR was used. SIRT1 activity was measured using a fluorometric kit and intracellular triglyceride levels were also measured using a triglyceride detection kit. And finally, the results were analyzed with t- test and one-way Anova statistical methods with p-value < 0.05.

As a result of the treatment of HepG2 fatty cells (fatty liver model) with Cur, the relative expression of SIRT1 gene (1.52 ± 0.8) and its enzyme activity (2.1 ± 0.7) increased significantly compared to the control group (for gene expression: 0.9 ± 1.79 and for enzyme activity: 0.8 ± 1.66). On the other hand, the relative expression of the FAS gene (0.6 ± 1.69) compared to the control group (0.8 ± 2.03), as well as the accumulated triglycerides in these cells, and has decreased significantly. Also, in the group treated with FCur compared to the control group, the level of SIRT1 gene expression (2.76 ± 1.16) and enzyme activity (3.2 ± 1.21) increased significantly, and the level of FAS gene expression (0.2 ± 1.1) decreased significantly compared to the control group. The increase in SIRT1 enzyme activity in the FCur group has increased more compared to Cur, and the decrease in FAS gene expression in the treatment of cells with FCur has been significantly higher compared to Cur. The reduction of intracellular lipid was somewhat higher in the treatment with FCur compared to the treatment with Cur. (In all evaluations, p-value < 0.01 for curcumin and p-value < 0.001 for its derivative).

It seems that curcumin analog (FCur) can be used as a medicinal supplement in the treatment of fatty liver, along with other common treatment methods, due to its wide range of pharmacological activities, including its effects on lipid metabolism in the liver.

 SIRT proteins are involved in the body's metabolic processes and homeostasis and are associated with oxidative stress due to aging and age-related diseases. Changes in these proteins in aging and the effect of physical activity on them have been less studied, so the aim of the present study was to investigate the effect of eight weeks of interval training on plasma levels of sirt1 and sirt3 proteins in inactive elderly men.

 In this study, 20 inactive elderly men aged 70-60 years were selected by available sampling and divided into experimental and control groups by simple random sampling. To investigate the effect of aging on plasma levels of Sirt1 and Sirt3 proteins, 10 inactive young men were selected by purposive sampling. The training program consisted of eight weeks of interval training with a moderate intensity of 50% of the reserve heart rate based on the principle of overload. Plasma levels of Sirt1 and Sirt3 proteins were measured in two stages of pre-test and post-test. One-way analysis of variance (ANOVA) was used to compare the pre-test of the three groups and the analysis of covariance was used to compare the post-test of the two groups of training elderly and control elderly.

 The results showed that plasma levels of Sirt1 and Sirt3 proteins in the elderly group were significantly lower than the young group (P <0.05). Also, due to eight weeks of interval training, the levels of the above proteins increased significantly (P <0.05).

According to the results of this study, it seems that  moderate interval exercise with increasing the Sirt1 and Sirt3 proteins, can reduce the oxidative stress caused by aging and lead to increased antioxidant defense and improve the quality of life in the elderly.

Mitochondrial function is regulated by the dark-light cycle under physiological and pathological conditions. Time-dependent exercise interventions may affect metabolic health in diabetic patients by regulating hyperglycemia. However, limited data are available about the correlation between the time of exercise and the regulation of muscle circadian rhythm in diabetes conditions. This study aimed to investigate the effect of time of exercise in the dark-light cycle on SIRT1 protein expression and the NAD+/NADH ratio in the gastrocnemius muscle of diabetic mice.

In this experimental study, thirty healthy male NMRI mice were randomly divided into three groups: control, diabetic, and diabetic+exercise. Type 2 diabetes was induced using a combination of a high-fat diet (five weeks) and streptozotocin injection (20 mg/kg body weight). Eight weeks of aerobic exercise with moderate intensity (5 days, 80-60 minutes) were performed on a treadmill at two times of the day, the early light phase (ZT3) at 9:00 AM and the early dark phase (ZT15) at 9:00 PM. Gastrocnemius muscles were collected at two times of the day, and SIRT1 protein expression was evaluated by Western blot analysis. The cellular NAD+/NADH content and glucose concentrations were measured using the colorimetric method. A two-way analysis of variance was used to analyze the data.

Eight weeks of aerobic exercise significantly increased SIRT1 protein and NADH levels (P<0.001) and improved hyperglycemia (P=0.005) only in the early dark phase. Aerobic exercise increased the NAD+/NADH ratio independently of time (P=0.003).

Proper exercise timing in the early dark, along with SIRT1 protein and NAD+ level circadian changes, may strengthen the effects of exercise and correct hyperglycemia more effectively.

Azoospermia is defined as the absence of sperm from semen. Spermatogenesis may be highly sensitive to compounds that interfere with mitochondrial energy metabolism and control of cellular respiration. The aim of this study was to evaluate the expression of SIRT1 and PGC-1α genes in testicular tissue of azoospermic rats treated with busulfan after a period of swimming training.

In this experimental study, 20 adult male wistar rats were randomly divided into four groups of healthy control: sham, azoospermia, exercise + azoospermia after azoospermia model was created. Exercise + azoospermia group, one month after azoospermia, performed low-intensity swimming exercises for 8 weeks, five days a week for 30 minutes each day. One-way analysis of variance was used to analyze the data.

The results showed that azoospermia group significantly reduced the expression level of SIRT1 and PGC-1α genes compared to healthy control group and 8 weeks of low intensity aerobic training caused a significant increase in Azoospermia + exercise group compared to azoospermia group. Has been.

In general, the results of the present study indicate that regular aerobic exercise such as low-intensity swimming in controlling the effects of infertility through the maintenance and development of mitochondrial biogenesis helps to improve the process of spermatogenesis.

Previous studies have shown the positive effect of aerobic exercise and curcumin on various variables in diabetes. Combination of these interventions may have an additive effect on these variables. The present study investigates the independent and combined effect of aerobic exercise and curcumin supplementation on cardiac SIRT1 gene expression and plasma resistin concentration in diabetic rats.

Forty male rats were equally divided into healthy control, diabetic control, diabetic exercise, diabetic curcumin, and diabetic curcumin+exercise. Aerobic exercise (five sessions/week, each session 30 minutes at a speed of 22 meters/minute, slope: five percent) and supplementation (30 mg/kg body weight, three days/week) were performed for eight weeks. Rats were sacrificed 48 hours after receiving the last intervention.

Diabetes decreased the expression of cardiac SIRT1 gene (p=0.001) and increased plasma resistin concentration (p =0.001). Exercise increased the expression of SIRT1 gene (p= 0.044) and decreased the resistance of resistin (p = 0.001) in diabetic rats. Curcumin also increased SIRT1 gene expression (p=0.048) and decreased resistin concentration (p=0.001) in diabetic rats. Compared to exercise or supplementation, combination of exercise and supplementation had more significant effect on increasing the expression of SIRT1 gene and decreasing the plasma concentration of resistin (p < 0.05).

In diabetic rats, aerobic exercise combined with curcumin has more pronounced beneficial effects on myocardial SIRT1 gene expression and plasma resistin concentrations from each alone.
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SIRT1 protein has been investigated as a key factor in many biological functions, such as longevity, oxidative stress, and bone mass in interaction with physical activity. The purpose of the present study was to compare the effect of combined and isometric exercise training on plasma level of SIRT1 in elderly women with osteopenia.

For this purpose, 45 women, aged 50-60 years, with osteopenia who were eligible for the present study, were selected and randomly divided into three groups of 15, each consisting of two exercise groups (Combined group and Isometric group) and one control group. After grouping the participants' initial blood sampling, Co group was trained 45-90 min per session (stretch, strength, endurance) and Iso group was trained 20-40 min (set, frequency, contraction time), three sessions per week, for 12 weeks. Data were analyzed using SPSS, version 24, running using paired t-test, One-way ANOVA, and Tukey post hoc test with the significance level set at 0.05.   

The ELISA results showed that both exercise methods had significant effects on SIRT1 compared to baseline (p=0/01). There was a significant difference between the two methods of training with control group on SIRT 1 level in the elderly women with osteopenia (p=0/001), but the difference between the two was not statistically significant (p=0/979). 

It seems that elevated SIRT1 level in aged people is compensatory mechanism of stress oxidative system and decreased activity in growth factor such as IGF1 in old age. It can be concluded that combined and isometric exercise could have positive effects on SIRT1 level in elderly women with osteopenia.