Key Findings:
Oxygen-derived free radicals cause oxidative damage of membrane lipids, proteins and carbohydrates which can damage myocardium tissue. Isoprenalin (ISO), a synthetic chemical can produce myocardial infarction by causing cytotoxic free radicals through auto-oxidation. In this study, flax lignan concentrate (FLC) effects were assessed on isoprenalin induced cardiotoxicity in Wistar rats. A pretreatment with flaxseed attenuated a hypotensive effect produced by isoprenalin and tachycardia. In the isoprenalin group a significant increase in the enzyme CK-MB (expressed in cardiac tissue) was noted indicating myocyte injury. In the flaxseed group, a lower increase in CK-MB after isoprenalin was shown and supported a cardioprotective activity of flax. The data also showed a link between free radicals and cardiovascular tissue injury, associated mainly with increase in vascular radical oxygen production. A 10-day administration of flaxseed reduced isoprenalin-induced tachycardia. Cardiotoxic effects of isoprenalin in flaxseed-pretreated animals were supported by hemodynamic, biochemical, and histopathological results. The antioxidant effect appears to contribute to the cardioprotective effect of flax lignin concentrate in isoprenalin-induced cardiotoxicity.
ABSTRACT:
The objective of the study was to evaluate the cardioprotective activity of flax lignan concentrate (FLC) in isoprenalin (ISO) induced cardiotoxicity in rats. Male Wistar rats (200–230 g) were divided into three groups. Group I: control, Group II: isoprenalin, Group III: FLC (500 mg/kg, p.o.) orally for 8 days and in group II and III isoprenalin 5.25 mg/kg, s.c. on day 9 and 8.5 mg/kg on day 10. On day 10 estimation of marker enzymes in serum and haemodynamic parameters were recorded. Animals were sacrificed, histology of heart was performed. Isoprenalin showed cardiotoxicity, manifested by increased levels of marker enzymes and increased heart rate. FLC treatment reversed these biochemical changes significantly compared with ISO group. The cardiotoxic effect of isoprenalin was less in FLC pretreated animals, which was confirmed in histopathological alterations. Haemodynamic, biochemical alteration and histopathological results suggest a cardioprotective protective effect of FLC in isoprenalin induced cardiotoxicity. (Authors abstract)