Iranian Journal of

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Background: Irisin was identified as a myokine secreted by exercise which plays an important role in energy metabolism and regulation of metabolic diseases such as diabetes. The aim of the present study is to investigate the effects of high intensity interval exercise (HIIE) and moderate intensity continuous exercise (MICE) on serum irisin and Subcutaneous UCP-1 in diabetic male rats.

Methods: In this study, 29 diabetic Wistar rats (12 week- age, 220-240 gr- weight) were assigned to 5 groups: immediately and 2 hours after high intensity interval exercise (HIIE0, HIIE2), immediately and 2 hours after moderate intensity continuous exercise (MICE0, MICE2) and control (C). Both MICE groups performed on the treadmill with intensity 60-65% vo2max for 40 minutes and both HIIE groups with intensity 90-95% vo2max in the 12 interval-one minute period and 1 minute rest intervals. ELISA was used to measure serum irisin and subcutaneous fat UCP-1. One-way ANOVA and Tukey post hoc test has used to data analysis, the level of significance has been considered at P≤0/05.

Results: Data analysis showed serum irisin levels in the HIIE0 group and subcutaneous fat UCP-1 in the HIIE2 significantly increased compared to the control group (p˂0/05). However, there was no significant difference between other research groups (P>0/05).

Conclusion: It seems high intensity of exercise had important roles in significant changes of serum irisin levels and subcutaneous fat UCP-1in diabetic rats.

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Background: Nesfetin-1 is known as the peptide which interfere in appetite and glucose hemostasis. The aim of the present study is to investigate the effects of two kinds of acute exercise to nesfatin-1 gene expression of diabetic rats.
Methods: In this study, has utilized the diabetic vistar staggy rats with STZ (12 week-age, 220-240 gr-weight). Animals were divided into four group: high DIABETIC MALE RATSintensity interval exercise (HIIE-0), control (C-0), (witch immediately has murdered after the exercise) and high intensity interval exercise (HIIE-2), and control (C-2), (which has murdered 2 hours after the exercise). HIIE group activated on the treadmill with 25 and 14 meter/minute in the 12 interval-one-minute period.
 Results: After removing hypothalamus and extraction of RNA, has down RT.PCR. The Independent T test analyzed and level of significance has been considering at 0/01 The exercise activity caused the significant increase of gene expression in the HIIE-0 group (P=0/001). But there was not significant increase in the HIIE-2 group (P=0/234).
 Conclusion: The results of this study displayed that one session of high intensity interval activity caused an increase immediately after the exercise in the hypothalamic nesfatin-1 gene expression of vistar staggy rats.
 

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Background: Fibroblast growth factor 21 (FGF21) plays an important role in regulation of energy metabolism and insulin resistance; however, the synergistic effects of high intensity interval training (HIIT) on FGF21 and insulin resistance are not elucidated which was focused in this study.
Methods: This experimental research was conducted by pretest- posttest design with control group. In this study, 24 obese men were assigned into two groups including
HIIT (n=12, age: 39.83 ± 5.63 years, weight: 100.83 ± 5.81 kg and body mass index: 32.73 ± 2.8 kg/m2) and Control (n=12, age: 39.41 ± 5.23 years, weight: 100.08 ± 4.71 kg, and body mass index: 32.34 ± 1.43 kg/m2). The HIIT group experienced eight weeks of intensive exercises (three sessions per week, four bouts in each session at the intensity of 85-90% of maximum heart rate (MHR) with 3-minute active rest intervals (at 60-50% of MHR) between exercise bouts. Blood samples were collected at baseline and also 48 hours following to the last training session. The data were compared using paired and independent samples t tests.
Results: HIIT resulted in a contemporary reduction of plasma glucose and serum insulin and FGF21 and also improved HOMA index (P˂0/05).
Conclusion: High intensity interval training plays an effective role in improvement of insulin resistance and reduction of serum FGF21 in obese subjects, which may be due to an improved FGF21 resistance.

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Background: The purpose of this study was to compare the effects of a 12 weeks interval training with high and moderate intensity on PGC-1α of skeletal muscle in type 2 diabetic male rats.
Methods: 40 male rats were divided into two groups: High fat diet (HFD) (n=32) and standard diet (C) (n=8) for 10 weeks. After inducing type2 diabetes via STZ, 8 diabetic rats (D) and 8 rats in group C rats sacrificed and the remaining 24 Rats were randomly assigned to three groups of diabetic control (DC), moderate intensity interval training (MIIT) and high intensity interval training (HIIT).The MIIT protocol includes 13 bouts of 4-minute activity with equivalent intensity of 60-65% vo2max  and the HIIT protocol includes 10 bouts of 4-minute activity with equivalent intensity of 85-90% vo2max with 2 minute active rest periods that was applied for 12 weeks, 5 sessions per week. Western Blot method was used to measure PGC-1α protein levels.
Results: The results showed that PGC-1α protein levels were significantly lower in the D group compared to the HC group. In contrast, the HIIT protocol resulted in an increase in protein levels of PGC-1α compared to DC2 group. While MICT had no significant effect on protein levels of PGC-1α (P <0.05). Also, there was no significant difference between the two training groups (P<0.05).
Conclusion: It seems that the intensity of interval training plays an important role in the regulation of skeletal muscle PGC-1α and possibly mitochondria biogenesis in type 2 diabetic rats.
 

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Background: Non-alcoholic fatty liver disease (NAFLD) is a pathological syndrome associated with increased serum levels of liver enzymes. The purpose of this study was to investigate the impact of exercise training on liver enzymes (ALT, AST, and GGT) and liver fat content in adults with NAFLD.
Methods: The PubMed, Web of Science, SID, Magiran, and Google scholar databases were searched until February 2022 for English and Persian articles. Meta-analyses were performed to compare the impact of exercise training on liver function in patients with fatty liver. SMD and 95% confidence interval (95% CI) were calculated using effect models. Also, the I2 test was used to determine heterogeneity, and the Funnel plot and Egger tests at a significant level of 0.1 were used to determine publication bias.
Results: The results of meta-analysis of 36 studies with 1602 patient with NAFLD, showed that exercise training caused a significant decrease in ALT enzyme [SMD=-0.73, (95% CI: -0.51 to -0.95), p=0.001], AST enzyme [SMD=-0.61, (95% CI: -0.39 to -0.83), p=0.001], GTT enzyme [SMD=-0.66, (95% CI: -0.18 to -1.14), p =0.007], and intrahepatic fat [SMD=-0.58, (95% CI: -0.78 to -0.38), p=0.001].
Conclusion: The findings of the present meta-analysis show the important role of exercise training (aerobic, resistance, and combined training) in improving liver function. So, all three types of aerobic, resistance, and combined exercise are suggested as a non-drug approach to reduce liver enzymes and intrahepatic fat for adults with NAFLD.

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Background: CTRP3 is known to be an adipose tissue-derived anti-inflammatory hormone that leads to improved insulin resistance. However, the effects of exercise training on this adipokine are poorly understood. Therefore, the aim of the present meta-analysis was to investigate the effect of exercise training on circulating CTRP3 levels in adults with metabolic disorders.
Methods: A comprehensive search was conducted in PubMed and Web of Science databases through October 2022 using the keywords "exercise training" and "CTRP3". The inclusion criteria for the current research included human studies with metabolic disorders, exercise training intervention, and circulating CTRP3 values. Standardized mean difference (SMD) and 95% confidence interval were calculated using random method.
Results: A total of 9 studies including 12 intervention arms and 365 participants with metabolic disorders were included in the meta-analysis. The results of data analysis showed that exercise training led to a significant increase in CTRP3 [0.57, (CI: 1.10 to 0.03) P=0.03]. Also, the results of the I2 test showed that there is a high and significant heterogeneity (I2 =84.59, P=0.001) and the results of the Egger test showed a significant publication bias (P=0.001).
Conclusion: Exercise training with a moderate effect size leads to a significant increase in circulating CTRP3 levels in individual with metabolic and cardiovascular diseases, which may be a mediator of the beneficial effects of exercise training.

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Background: Fetuin-A, as a hepatokine, plays an important role in the regulation of whole-body metabolism, which is increased with chronic diseases. Therefore, the aim of this meta-analysis is to investigate the effect of exercise training on Fetuin-A levels in individuals with metabolic and kidney diseases.
Methods: A systematic search was conducted in PubMed, Web of Science, and Google Scholar databases until November 2022 using the keywords "exercise training" and "Fetuin-A". To determine the effect size, standardized mean difference (SMD) and 95% confidence interval were calculated using CMA2 software. Heterogeneity was evaluated using the I2 test, and publication bias was evaluated by visual interpretation of the funnel plot and Egger's test. The quality of the included studies was evaluated using the PEDRO checklist.
Results: A total of 16 studies including 21 trials arms and 554 subjects with type 2 diabetes, obesity and kidney disease were included in the meta-analysis. Exercise training resulted in a significant decrease in Fetuin-A levels [-0.93 (CI: -1.35 to -0.51) P= 0.001]. There was a high heterogeneity (I2= 89.24, P= 0.001) and also a significant publication bias (P= 0.001). The results of subgroup analysis based on the type of exercise training showed that aerobic training resulted in a significant decrease in Fetuin-A (P= 0.001) while the reduction of this marker with combined training was not significant (P= 0.33).
Conclusion: Exercise training, especially aerobic training, results in a decrease in Fetuin-A levels in metabolic patients, which may be contributed to the beneficial effects of exercise.

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Background: Adiponectin is one of the most well-known adipokines with anti-inflammatory effects that plays an important role in regulating the whole-body metabolism. The aim of this study was to investigate the effect of high-intensity interval training (HIIT) versus moderate intensity continuous training (MICT) on the circulating levels of adiponectin in individuals with and without metabolic disorders.
Methods: A systematic search was conducted in the databases of PubMed, Web of Science, Academic Jihad Center and Magiran using the keywords "HIIT" and "adiponectin" to identify Persian and English languages published articles until October 2022. Effect size (SMD) and 95% confidence interval were calculated using CMA2 software. I² test for calculation of the heterogeneity and visual interpretation of funnel plot test and Egger test for assessment of the publication bias were used.
Results: Data analysis of 28 interventions (24 studies) showed that HIIT resulted in a significant increase in adiponectin [0.40 CI: 0.12 to 0.68), P=0.004]. Also, the data analysis of eight interventions showed that HIIT led to a non-significant increase in adiponectin compared to the MICT [0.41 CI: -0.04 to 0.86), P=0.07].
Conclusions: The findings of the present study showed that HIIT is a suitable and efficient training method to increase adiponectin, especially in people with metabolic disorders.

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Background: The purpose of this study was to investigate the effect of two types of interval and continuous training on apolipoprotein M, TNF-α and IL-6 of visceral fat in rats fed a high-fat diet.
Methods: Twenty-four male Wistar rats were randomly divided into four groups including standard diet (ND), high-fat diet (HFD), high-fat diet with moderate intensity continuous exercise (HFD+MICT), high-fat diet with high intensity interval training (HFD+HIIT). The HIIT and MICT groups performed their group specific training for 8 weeks, 5 sessions per week. The HIIT protocol consisted of 6 bouts of 4-minute exercise at 85-90% of the maximum speed, which had a 2-minute active rest, and the MICT protocol performed at 65-70% of the maximum speed. Protein levels of apolipoprotein M, TNF-α and IL-6 in visceral fat were measured using western blot method.
Results: Eight weeks of HFD increased the protein levels of apolipoprotein M, TNF-α, and IL-6 in visceral fat compared to the ND group (P< 0.05). In contrast, both HIIT and MICT protocols led to a significant reduction of visceral fat IL-6 compared to the HFD group (P= 0.001). Also, MICT caused a significant decrease protein levels apolipoprotein M compared to the HFD group (P= 0.04). However, both exercise protocols had no significant effect on TNF-α (P< 0.05). Also, there was no significant difference between training groups (P< 0.05).
Conclusion: Exercise training improves adipose tissue inflammatory markers in high-fat diet-fed rats, and moderate-intensity continuous training may be a more appropriate approach.