Mechanism of protective action of mangiferin on suppression of inflammatory response and lysosomal instability in rat model of myocardial infarction.

Lysosomal instability has been suggested as a major factor in the development of cellular injury during myocardial necrosis through the formation of inflammatory mediators. The present study was designed to investigate the effect of mangiferin on lysosomal hydrolases and TNF-alpha production during isoproterenol (ISPH) induced myocardial necrosis in rats. The rats given ISPH (200 mg/kg body weight twice, subcutaneous) for 2 days showed a significant increase in plasma TNF-alpha production, serum and heart lysosomal hydrolases activity. ISPH administration to rats resulted in decreased stability of the membranes, which was reflected by the lowered activity of cathepsin-D and beta-glucuronidase in mitochondrial, nuclear, lysosomal and microsomal fractions. Pretreatment with mangiferin (100 mg/kg body weight, intraperitoneally) for 28 days, significantly prevented the alterations and restored the enzyme activities to near-normal status. These findings demonstrate that mangiferin could preserve lysosomal integrity through decrease in the inflammatory process and hence establish the cardioprotective effect of mangiferin. (c) 2009 John Wiley & Sons, Ltd.