The present study was designed to examine the effect of heme oxygenase-1 (HO-1) induction by cobalt protoporphyrin (CoPP) on the cardiac functions and morphology, electrocardiogram (ECG) changes, myocardial antioxidants (superoxide dismutase [SOD] and glutathione [GSH]), and expression of heat shock protein (Hsp) 70 and connexin 43 (Cx-43) in myocardial muscles in isoproterenol (ISO) induced myocardial infarction (MI). Thirty two adult male Sprague Dawely rats were divided into 4 groups (each 8 rats): normal control (NC) group, ISO group: received ISO at dose of 150 mg/kg body weight intraperitoneally (i.p.) for 2 successive days; ISO + Trizma group: received (ISO) and Trizma (solvent of CoPP) at dose of 5 mg/kg i.p. injection 2 days before injection of ISO, with ISO at day 0 and at day 2 after ISO injections; and ISO + CoPP group: received ISO and CoPP at a dose of 5 mg/kg dissolved in Trizma i.p. injection as Trizma. We found that, administration of ISO caused significant increase in heart rate, corrected QT interval, ST segment, cardiac enzymes (lactate dehydrogenase, creatine kinase-muscle/brain), cardiac HO-1, Hsp70 with significant attenuation in myocardial GSH, SOD, and Cx-43. On the other hand, administration of CoPP caused significant improvement in ECG parameters, cardiac enzymes, cardiac morphology; antioxidants induced by ISO with significant increase in HO-1, Cx-43, and Hsp70 expression in myocardium. In conclusions, we concluded that induction of HO-1 by CoPP ameliorates ISO-induced myocardial injury, which might be due to up-regulation of Hsp70 and gap junction protein (Cx-43).

Introduction: Nonalcoholic fatty liver disease (NAFLD) is a prevalent chronic liver disease, which threatens the health of both adults and children. It is strongly associated with type 2 diabetes mellitus, obesity and insulin resistance. In the present study, we evaluate the effect of Stevia rebaudiana and exercise on fatty liver in T2DM. Methods: Thirty-two male Sprague Dawely rats were divided into normal control, diabetic, Stevia treated diabetic, and exercise treated diabetic rats. Biochemical parameters, oxidative stress markers, and histopathological examination for liver tissue were done. Results: in diabetic group, blood glucose level, HOMA index, cholesterol level, triglycerides level, bilirubin level, liver enzymes (ALT& AST), and MDA were significantly increased. While insulin level, GSH, and CAT activity were significantly decreased when compared to normal control group. Biochemical parameters and Oxidative stress markers were improved in the treated groups, the improvement was more significant in exercise treated group than Stevia treated group. Histopathological examination confirmed our results. Conclusion: Stevia rebaudiana and exercise could protect against liver injury induced by T2DM, as they improve glycemic state, liver enzymes, and oxidative stress markers Keywords -NAFLD -T2DM -Stevia -Exercise Bull. of Egyp. Soc. Physiol. Sci.