Background: Renal injury following ischemia - reperfusion (I/R) is still an unavoidable problem in many remedial and medical situations. Portulaca oleracea (PO) has been known for its anti-oxidative effects. Then, the present study aimed to investigate the effect of ethanolic extract of PO (EEPO) on the renal function and antioxidant status after induction of I/R injury in the rat kidney.

Materials and Methods: A total of 30 rats (Wistar) were divided into five groups (n = 6 each). Sham group: underwent laparotomy without I/R, EEPO group: EEPO administered 300 mg/kg then was operated like sham, I/R group: was underwent renal ischemia/reperfusion only, EEPO150+ I/R and AEPO300+ I/R groups: were administered PO 150 and 300 mg/kg then underwent I/R operation. PO extract was administered for 5 days in the relevant groups by gavage. Serum urea and creatinine (Scr), the level of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH) and total antioxidant activity (TAA) were determined. Data were analyzed by ANOVA and post hoc LSD test. P values of 0.05 or less were considered statistically significant.

Results: Induction of I/R and pretreatment with PO extract, increased the level of superoxide dismutase (SOD) in comparison with sham group (p<0.05, p<0.001). There were no significant differences in the levels of MDA, GSH and TAA among different groups. On the other hand, the Scr and serum urea of the I/R and treated groups were elevated compared to the sham group (p<0.001).

Conclusion: Ethanolic extract of PO did not strongly affect the renal antioxidant status and could not prevent the renal injury following I/R.

Abstract

Background: Recently a myokine named irisin has been discovered that effects on obesity, metabolism and glucose homeostasis through browning white adipose tissue and thermogenesis. However, the effects of type and intensity of exercises on it have remained unclear. The purpose of this study was to evaluate the effects of two acute eccentric and concentric exercises on serum irisin level and insulin resistance in obese sedentary women.

Materials and Methods: The study was quasi-experimental. 15 female students with a body mass index above 30 kg/m² and mean age 24.86±2.87 years participated in the study. After measuring the maximal uptake oxygen of participants, they did two acute eccentric and concentric exercises using treadmill in a cross-over design within 10 days. After at least 8 hours- fasting, blood samples were collected before and immediately after each activity, to measure the levels of irisin, glucose and insulin. Data were analyzed using paired t-test and repeated measures ANOVA. In addition, Pearson correlation was used to examine the relationship between variables.

Results: the irisin levels increased significantly after both types of exercises (p<0.05), that this increase in concentric activity was more than eccentric activity. Insulin resistance increased immediately after both exercises as well, that this increase in concentric exercise was statistically significant (p<0.05).

Conclusion: However, both eccentric and concentric exercises had no effect on improving insulin resistance in obese women, but they can be considered as a good stimulus for the secretion of Irisin.