[ effect of high intensity interval training on the serum levels of irisin and fibroblastic growth factor-21 [FGF-21], and insulin resistance in obese male rats]

Introduction: the purpose of this study was to investigate the effects of high intensity interval training [HIIT] and moderate intensity continuous training [MICT] on irisin, FGF-21 and insulin resistance in obese male rats

Material and Methods: forty male rats were divided into two groups: high-fat diet [n=32] and standard diet [n=8], for 10 weeks. After inducing obesity, eight rats from the high-fat diet group [O] and eight from the standard dietary group [C] were sacrificed, and the other obese rats were randomly divided into three groups: obesity control [OC], moderate intensity continuous training [MICT] and high intensity interval training [HIIT]. The HIIT protocol, including 10 bouts of 4-minute activity with equivalent intensity of 85-90% vo2max and 2 minute active rest periods, and the MICT protocol with equivalent intensity of 65-70% VO2max, with covered distance matched to that of the HIIT protocol, were performed for 12 weeks and 5 sessions per week. Serum samples were collected in two steps [after completion of diet and training protocols] to measure serum levels of irisin, FGF-21, insulin and glucose by ELISA

Results: in the comparison of the HIIT group to the OC group, serum levels of irisin [6.43 +/- 0.93 ng/ml vs. 4.61 +/- 0.61 ng/ml, p=0.003] and FGF-21 [1658 +/- 206.5 ng/l vs. 1093 +/- 125.97 ng/l, P=0.007] significantly increased, while MICT had no significant effect on these two hormones [P=0.29, P=1.00 respectively]. Also, when comparing both the HIIT and MICT groups to the OC group, serum levels of glucose [HIIT: 111.16 +/- 4.07 mg/dl, MICT: 117.5 +/- 1.37 mg/dl vs. 154.66 +/- 13.21 mg/dl, P=0.001, P=0.001 respectively] and insulin resistance index [HIIT: 1.96 +/- 0.20, MICT: 2.53 +/- 0.46 vs. 3.89 +/- 0.54, P=0.001, P=0.01 respectively] significantly decreased; although, serum insulin reduction [1.49 +/- 0.15 ng/ml vs. 2.14 +/- 0.43 ng/ml, P=0.018] was only significant in the HIIT group [P=0.018]

Conclusion: it seems that both HIIT and MICT training protocols lead to improved insulin resistance in obese rats. However the increase in serum irisin and FGF-21 was significant only in the HIIT group, suggesting that exercise intensity plays an important role in regulating the secretion of these hormones

[ effect of eight weeks of aerobic training on serotonin and tryptophan hydroxylase levels in hippocampus in type 2 diabetic rats]

Backgrounds and Aim: Aerobic exercise has proven benefits in treating and reducing the incidence of complications of chronic diseases such as diabetes. In this study we evaluated the effect of aerobic training on serotonin and tryptophan hydroxylase levels in hippocampus in type 2 diabetic rats

Materials and Methods: 30 rats were randomly divided into healthy control,diabetic control, exercise diabetic groups. 2[nd] and 3[rd] groups were made diabetic by intraperitoneal injection of streptozotocin [37mg/kg], two weeks after receiving high-fat diet. Groups of aerobic exercise performed treadmill exercise 5 times/ week for 8 weeks with duration and intensity of 55min /d and 26m/min respectively in the final weeks. 24 hours after the last exercise blood samples and hippocampus tissue samples were obtained and concentrations of serotonin [micro g/g] and tryptophan hydroxylase were measured by Elisa and western blotting methods respectively. We used ANOVA and Tukey post hoc test for data analysis

Results: Statistical analysis showed that the diabetic group had significantly lower serotonin levels compared to the healthy control group [P=0.001] and exercise diabetic group [P=0.01].The mean tryptophan hydroxylase level of the diabetic groups were significantly lower than that of the healthy control group [P=0.001]. The amount of tryptophan hydroxylase was significantly higher in the exercise diabetic group compared to that in the diabetic control group [P=0.001]

Conclusion: In this study, diabetes led to reduction of serotonin and tryptophan hydroxylase levels in the hippocampus. Also eight weeks of aerobic exercise increased tryptophan hydroxylase level in the hippocampus of the diabetic rats

Distribution of hepatitis C virus genotypes in iranian patients with congenital bleeding disorders

Chronic hepatitis C virus [HCV] infection is the major cause of liver disease related morbidity and mortality in hemophilic patients who needs regular blood product administration. Although genotype of infecting HCV is one of the prime predictors of response to antiviral therapy however, its distribution in hemophilic patients is still unclear and just few studies with low sample sizes have investigated this issue. Therefore, in this study, we aimed to identify this distribution in 367 Iranian hemophilic patients. Blood samples were received from 367 hemophilic patients with chronic hepatitis C detected during a nationwide screening program who referred to our center for therapeutic measures. HCV RNA viral load was detected using Amplicor test [Version 2]. Genotyping was performed by genotype specific primers. HCV genotype distribution was 1a in 58%, 3a in 18.5%, 1b in 14.7%, 4 in 1.1%, 2 in 0.8% and mixed in 6.2% and finally 0.5% of isolates were non-typable. Serum liver enzymes were not associated with HCV viral load and genotypes. Patients with severe bleeding tendency had significantly lower serum liver enzymes than those with a mild bleeding tendency. Genotype 1a followed by 3a and 1b were the most frequently detected HCV genotypes in Iranian hemophilic patients and there was no association between splenomegaly and viral markers and liver enzymes in these patients

Relationship between insulin like growth factor-1 and leptin in type II diabetic patients

Diabetes is a common endocrine disease in humans. Leptin secretion is influenced by many factors and although the growth hormone/insulin like growth factor [GH/IGF] axis plays an important role in the regulation of body composition, the physiological interaction between Leptin and IGF-1 system remain unknown. The aim of this study was to investigate the correlation between Leptin and IGF-1 in type II diabetics and controls. This case-control study was consisted of 38, type 2 diabetics [20 males and 18 females, mean age 49.33 +/- 11.33, years] and 46 healthy controls [16 males and 30 females, mean age 49.52 +/- 7.99, years]. We measured the concentrations of fasting plasma glucose [FPG], IGF-1, hemoglobin A1C [HbA1c] and insulin like growth factor binding protein-3[IGFBP-3] in both groups. FPG was measured by the enzymatic glucose oxidase method and the Hb Gold analyzer HPLC was used to measure HbA1C. For determination of leptin, IGF-1, IGFBP-3 and insulin concentrations, the enzyme linked immunosorbent assay [ELISA] method was used. P< 0.05 was considered statistically significant. Means of BMI and age did not differ significantly between the two groups. Mean serum levels of IGF-1, leptin, insulin, FPG and HbA1c concentrations in type 2 diabetics were significantly higher than in controls [p<0.05]. In both groups, mean serum levels of leptin in males, were statistically lower than in females. Strong correlations were found between IGF-1 and IGFBP-3, leptin and insulin, IGF-1 and age, and between BMI and FPG in both patients and controls [p<0.05]. A negative correlation was observed between IGF-1 and HbA1c in patients and controls [p< 0.05]. It is concluded that leptin and the IGF-1 system, could influence body composition and fat content, particularly in obese and overweight diabetic patients

[Prediction of LV dysfunction in basis of ventricular depolarization time in patients with left bundle brunch block]

Prolongation of ventricular depolarization time [QRS duration] particularly in left bundle branch block [LBBB] is commonly associated with many cardiac diseases. Electrocardiographic study of QRS duration and electrical axis may be predictors of sever LV systolic dysfunction. In this prospective study that was conducted in CCU and out-patient clinic of Shaheed Beheshti hospital in Babol [2000-2003], 150 patients with the diagnosis of LBBB were assigned in two groups [one QRS >/= 160 and the other with QRS<160 millisecond.]. Then relationship between QRS-duration, left axis deviation [LAD] and echocardiographic LV ejection fraction [EF] were analysed using SPSS software and T-test, chi-square and linear regression analysis in step wise manner. There was no significant correlation between age and gender with duration of QRS and LAD among patients with LBBB [NS]. The mean +/- standard deviation of EF in the patients with a QRS duration >/= 160 millisecond was significantly lower than the mean of EF in the patients with a QRS duration <160 millisecond [%[54.50 +/- 10.55] vs.%[23.89 +/- 5.47] p<0.001]. Pearson correlation between EF and LAD was lower than its value between EF and QRS duration [r=0.378 p=0.006 vs. r=0.926 p<0.001, respectively]. Evaluating QRS duration in the presence of LBBB has a significant inverse relation with EF and when its value is greater than 160 millisecond, it could be a simple and appropriate marker of significant left ventricular dysfunction