Chromium, the natural lipid-modulating therapy, protects the rat myocardium against ischemic-reperfusion hazards

ABSTRACT

This study was carried out on 20 male albino rats weighing 200-250 grams each. They were divided into 2 groups Group I [n = 10], used as control; Group II [n = 10], chromium supplemented rats at a dose of 20 micro g/ rat/day for 12 weeks. After that, blood samples were collected for estimation of serum triglycerides [TG], total cholesterol [TC], high density lipoprotein-cholesterol [HDL-C] as well as fasting glucose and insulin levels. This was followed by ischemia-reperfusion of isolated hearts. After 30 minutes of reperfusion, the hearts were sent for histopathological examination, LDL-cholesterol [LDL-C] and HDL/total cholesterol ratio were also calculated. The results of this study showed that chromium supplementation induced significant reduction in the levels of serum glucose, insulin, TG, LDL-C and TC accompanied by a significant increase in HDL-C and HDL-C/TC ratio. Chromium supplemented hearts, also showed better recovery of myocardial activity at different periods of reperfusion compared to control hearts in the form of a significant increase in heart rate [HR], peak tension [PT] and myocardial flow rate [MFR] as well as an insignificant reduction in time to peak tension [TPT] and half relaxation time [1/2RT]. Histopathological examination of hearts showed a clear picture of ischemia in control hearts compared to chromium supplemented hearts. We can conclude that chromium supplementation can protect the rat myocardium against ischemic-reperfusion hazards and this may be due to promoting the healthy blood lipid level and reducing fasting insulin levels which may reflect enhancement of tissue sensitivity to insulin