نشریه مطالعات کاربردی علوم زیستی در ورزش
پیاپی 21 (بهار 1401)

It is well recognized that mitochondrial transcription factor A (TFAM) and nuclear respiratory factor-1 (NRF-1) are the key regulators of mitochondrial biogenesis and oxidative phosphorylation. This study investigated whether 12 weeks of interval training with high (HIIT) and moderate (MIIT) intensity influences the key regulatory molecules of mitochondrial biogenesis (TFAM and NRF-1( of skeletal muscle in type 2 diabetic male rats.

Forty male rats (age: 8 weeks, weight: 180±20 g) were divided into two groups: high fat diet (HFD) including 32 rats, and standard diet (C) including 8 rats. After inducing type 2 diabetes via Streptozotocin, 8 diabetic rats (D) and 8 rats in group C were sacrificed and the remaining 24 rats were randomly assigned to three groups including diabetic control (DC), MIIT, and HIIT. The MIIT protocol includes 13 bouts of 4-minute activity with an equivalent intensity of 60-65% VO2max and the HIIT protocol includes 10 bouts of 4-minute activity with the equivalent intensity of 85-90% VO2max with 2 minute active rest periods that was performed for 12 weeks, and 5 sessions per week. Western blotting was used to measure the levels of TFAM and NRF1 proteins; and the parametric and non-parametric tests were used to analyze the data at the p≤0.05 level.

The results showed that TFAM and RNF-1 protein levels were significantly decreased in the D group compared to the C group (p<0.01). Indeed, exercise training resulted in an insignificant increase in protein levels of NRF-1 compared to the DC group (p>0.05); while HIIT and MIIT had no significant effect on protein levels of TFAM (p>0.05).

It seems that the HIIT and MIIT programs improve mitochondrial respiration but have no effect on mitochondrial biogenesis in type 2 diabetic rats. However, further research is needed for definite results.

Endurance training can be associated with reducing body fat. The aim of the present study was to investigate the effects of 12 weeks progressive endurance training and high fat diet on gene expression of β3-Adrenergic (β3-ARs) and cyclic adenosine monophosphate (cAMP-r) receptors of brown adipose tissue in obese male Wistar rats.

Fifteen male Wistar rats were randomly divided into three groups (n=5) including endurance training with high fat diet group, control group with normal diet and control group with high fat diet. High fat diet was composed of 40% fat, 13% protein and 47% carbohydrate. The endurance training included running at speed of 20 m/min for 15 min in 1st week and reached to 25 min for 31 min/day in 12th weeks.  The gene expression of β3-ARs and cAMP-r were examined by RT & PCR methods. To compare the cAMP-r and β3-ARs between groups, the Kruskal-Wallis and Mann-Whitney U tests was applied at the significant level of p<0.05.

There was no significant difference in cAMP-r gene expression (p=0.47) between control groups with high fat diet, control group with normal diet and endurance training group with high fat diet, but there was a significant difference in the expression of β3-ARs gene (p=0.03) between the groups and these changes was higher in the endurance training group with high fat diet than the control groups with normal and high fat diet.

The results of the present study showed the effect of moderate-intensity endurance training with high-fat diet on β3-ARs gene expression, which can lead to increase energy consumption and also reduce the obesity. However, changes in cAMP-r gene expression indicate a non-significant improvement, which may be reflected changes in the intensity and duration of training in future research.

Endurance training can reduce the risk of cardiovascular diseases by affecting on platelet indices, moreover it has been shown that resveratrol supplement also has a similar effect of training on platelet function. The aim of this study was to evaluate the effects of 12 weeks of trans-resveratrol supplementation and endurance training on platelet indices in response to exercise.

In this study, 32 male Wistar rats (age, 8 weeks) were randomly divided into 4 groups including control (C), supplement (S), training (T) and training-supplementation (T+S). T+S and T groups performed a 12 weeks of endurance training, 5 days a week, on a motorized treadmill. The training protocol were started for 10 minutes at a speed of 10 m/min in the first week and reached up to 60 minutes at 25 m/min at the end of the training. S and T+S groups received 10 mg trans-resveratrol per kilogram of body weight per day for 5 days a week. Forty-eight hours after the last training session, all groups performed an acute exercise trial at speed of 25 m/min and slope of 10 degrees up to exhaustion. Blood samples were taken immediately after exercise and analyzed by electrical impedance method for platelet indices include platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW) and platelet percentage (PLC). Data were analyzed by one-way analysis of variance and Bonferroni post hoc test at the significant level of p<0.05.

The MPV responses to acute exercise were significantly different among the 4 groups (p=0.03). Comparison of the couples showed that the MPV in group S was significantly lower than C (p=0.01) and T (p= 0.01) groups. There was no significant difference between the responses of other indicators to exercise (p>0.05).

Consumption of the trans-resveratrol supplementation for 12 weeks, significantly reduced the mean platelet volume of group S in response to acute exercise. Combining the supplement with training and training had no effect on the response of platelet indices to acute exercise.

Adipolin is an anti-inflammatory and insulin sensitive adipocytokine that can be considered as modulating glucose intolerance and also insulin resistance. It is secreted from white adipose tissue and its level can decrease in obese and diabetes people. The aim of this study was to evaluate the effect of eight weeks of continuous training with 45-60% maximum heart rate on plasma levels of adipolin, insulin sensitivity, and body fat percent in overweight and obese women.

In this semi experimental study, 30 overweight and obese women were selected and randomly divided into experimental (n=15) and control (n=15) groups. The experimental group performed running protocol at an intensity of 45-60% maximum heart rate for 30 minutes. The exercise started with a 45% maximum heart rate in the first session, while the intensity was gradually added about 5% every week, based on the subject’s physical fitness level. Further, it was maintained up to the end of the program when the subjects reached their 60% maximum heart rate. The blood sample was measured after 12 hours of fasting in pre and post-test phases to measure the variables. The Shapiro-Wilk normality test was done while intra–inter group changes were identified by paired t and independent t-tests respectively, at the significance level of p<0.05.

After eight weeks of continuous training with light to moderate intensity, plasma adipolin levels (p<0.001) and insulin sensitivity (p<0.001) increased significantly as compared to pre-workout while body fat percentage was significantly decreased (p<0.0001). The comparison between the groups showed that plasma adipolin levels (p<0.001) and insulin sensitivity (p<0.001) significantly increased in the experimental group compared to the control group, that the body fat percentage also indicated a significantly (p<0.001) decrease.

Based on the results of this study, light to moderate intensity continuous training can be considered in some disorders associated with overweight and obesity, by increasing adipolin, insulin sensitivity, and reducing body fat percentage.

Little is known about the concomitant effects of high intensity interval training (HIIT) and curcumin on arsenic toxicity in the brain. The aim of the present study was to evaluate the effects of HIIT and curcumin supplementation on cerebral malondialdehyde (MDA), nitrite, homocysteine and also expression of caspase3, caspae-8 and caspase-9 protein in rats exposed to arsenic.

In this experimental study, 48 male rats were randomly divided into six groups: arsenic+training, arsenic+curcumin, arsenic+training+curcumin (concomitant), arsenic, ethanol-control and normal-control. Arsenic five mg/kg/day and curcumin 15 mg/kg/day were consumed orally (gavaged) for six weeks. HIIT were conducted for six weeks (five sessions/week, each session lasted 60 min) consisted of four min running bouts at 85-90% of vVO2max with two min recovery intervals at 50-60% of vVO2max. Elisa, Western blot and also TBARS as well as Grace reaction methods were used to quantify cerebral homocysteine, caspase expression, MDA and nitrite levels respectively. Data were analyzed by one-way analysis of variance and Tukey post hoc tests at the p<0.05 level.

Arsenic exposure significantly elevated brain caspase-3, -8 and -9 expression, as well as MDA and homocysteine levels (p<0.05). All of three interventions including HIIT, curcumin and their concomitance obviated arsenic induced cerebral MDA elevation compared to normal control group (p<0.05), however; it could not fully corrected homocysteine levels (p>0.05). Caspae-8 and -9 protein expression levels were restored to normal control group level, just in concomitant group (p<0.05).

Arsenic exposure leads to an increased rat cerebral homocysteine, lipid peroxidation as well as intrinsic and extrinsic apoptotic pathways activation. While HIIT, curcumin and their concomitance prevented arsenic induced cerebral lipid peroxidation, only with curcumin supplementation remarkable benefits were observed for rest of variables. Further, only in the concomitant group, the arsenic induced elevations in the activity of both the intrinsic and extrinsic apoptotic pathways were fully prevented. However, more researches should to be done because of the study limitations and lack of similar evidence in human population.

The protective role of glutamine against protein breakdown and also its potential effect on rehabilitation after exhaustive activities is not well understood. The aim of this study was to investigate the effect of acute glutamine supplementation before an exhaustive activity on blood lactate levels and pain index in young athletes.

In this quasi-experimental double-blind study, 16 male athletes (age: 21.87±1.77 years, weight: 72.65±6.02 kg, body mass index: 23±1.75 kg/m2) were randomly divided into two groups including glutamine (n= 8) and placebo (n= 8) groups. The experimental group consumed 0.6 g of glutamine supplement per kg in body weight with 500 ml of water half an hour before activity. Moreover, the placebo group used 2% dextrin solution without glutamine. Lactate level was measured using a lactometer and pain index was evaluated with the numerical pain raiting scale (NPRS) questionnaire before, immediately, 30 minutes and 60 minutes after an exhaustive protocol. Data were analyzed using repeated measures analysis of variance and Beferroni post hoc test was applied at the significance level of p<0.05.

Blood lactate level and pain index significantly increased after exhaustive activity in both groups (p<0.05). However, blood lactate levels and pain index were significantly lower 30 minutes after activity as compare of the initial phase after exercise in both groups (p<0.05). The decreasing process of lactate level and pain index continued up to 60 minutes after the end of activity, but this decrease was greater in the glutamine supplement than in the placebo group (p<0.05). There was also a significant difference between blood lactate levels (30 and 60 minutes) and pain index (immediately, 30 and 60 minutes) after the exhaustive activity (p<0.05).

It is recommended that athletes can use glutamine supplementation to reduce blood lactate levels and pain index before their performing exhaustive activities.

Although exercise training and antioxidants improve brain health, interactive effect of resistance training and Royal jelly has not yet been well established. Therefore, the aim of the current study was to investigate the effect of resistance training along with Royal jelly supplementation on hippocampal gene expression of nerve growth factor (NGF) and tyrosine kinase A (TrkA) receptor in rat model of Alzheimer’s disease.

In this experimental study, 42 male Sprague-Dawley rats were injected by Trimethyltin (8 mg/kg/body weight). Then, the rats were randomly divided into 7 equal groups including control, resistance training, resistance training+100 mg/kg Royal jelly supplementation, resistance training+200 mg/kg Royal jelly supplementation, 100 mg/kg Royal jelly supplementation, 200 mg/kg Royal jelly supplementation and sham groups. The resistance training protocol was performed for 8 weeks, three sessions per week at intensity to 30-100% of their body weight. Gene expression was assessed using Real-Time PCR and all primers were designed by Allele IDv7.8 software. Data were analyzed using two-way analysis of variance and Bonferroni post hoc tests at the p<0.05.

The resistance training induced a significant increase in NGF expression (p= 0.001). Moreover, 100 and 200 mg/kg Royal jelly supplementation, resistance training+100 and 200 mg/kg Royal jelly supplementation resulted in a significant increases in expression of NGF and TrkA receptor (p=0.001). In addition, the effect of royal jelly supplementation on NGF and TrkA receptor expression was dependent on its dosage, where the dose of 200 mg/kg was significantly higher than the dose of 100 mg/kg (p=0.001).

Both resistance training and Royal jelly supplementation, alone and synergistically, can increase neurotrophins expression in the hippocampus of Alzheimer’s rats; however higher dose of Royal jelly supplementation may induce more improvement.

Chitinase-3-like protein (YKL-40) is an inflammatory biomarker associated with asthma and allergic diseases; While exercising may reduce the inflammatory effects of asthma. The present study has been undertaken to investigate the effects of 8 weeks of interval, resistance and concurrent training on YKL-40 and immunoglobulin E (IgE) levels in the lung of asthmatic Wistar rats.

Twenty five male Wistar rats were randomly divided into five groups including control (C), interval training (IT), resistance training (RT), concurrent training (CO), and salin (S) groups. The asthmatic groups (C, IT, RT and CO) received (1 ml) of Ovalbumin intraperitoneally injection after exercise and exposed to Ovalbumin challenge three times per week for 20 minutes. The IT group (three times per week, 60-80% maximum capacity, 30 minutes), RT group (three times per week, 60% one-repetition maximum, three sets of 10 repetitions) and CO group (combination of IT+RT) also completed intervention training protocols for eight weeks. YKL-40 and IgE levels were measured by ELISA method. One-way analysis of variance and LSD post hoc tests were used for data analysis at the p≤0.05 level.

YKL40 levels in IT (p= 0.05), RT (p=0.005) and CO (p=0.001) groups significantly increased compared to the control group; so that, CO training induced more changes in YKL40 compare to other training intervention groups (p<0.05). Moreover, IgE level increased significantly in the IT (p<0.005), RT (p<0.03) and CO (p<0.004) groups than control group.

It seems that the use of eight weeks interval, resistance and concurrent training cannot counteract the effects of inflammatory of YKL-40 in the asthma and play a protective role.