Search

Background: Diosgenin, a steroidal saponin from plants, exhibits many biological potentials. Herein, the cardioprotective role of diosgenin is studied. Materials and Methods: The effect of diosgenin, isolated from Dioscorea bulbifera, was studied on hypoxia-reoxygenation (HR) in H9c2 cardiomyoblast cells. The amount of diosgenin in the plant extract was analyzed by high-performance thin layer chromatography using a solvent system comprising of chloroform:methanol:acetic acid:formic acid (13:4.5:1.5:1). Cardioprotection was checked by (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Further, the release of lactate dehydrogenase, an enzyme released during cell death was checked. The proteins responsible for cell death (Bax) and cell survival (Bcl-2, hemeoxygenase-1 and Akt) were analyzed using Western blot to check the cardioprotective role of diosgenin. Conclusion: Supplementation of diosgenin mitigates HR injury, thereby exhibiting cardioprotective potential. SUMMARY The cardioprotective effect of Diosgenin was evidenced from the improved cell survival after hypoxia-reoxygenation injury demonstrated through MTT cell survival assay.The release of lactate dehydrogenase, an enzyme released during cell death was decreased by Diosgenin.Diosgenin upregulated the pro-survival molecules like B-cell lymphoma 2 (Bcl-2), heme oxygenase-1 and the phosphorylation of ATK (at serine 473); and at the same time pro-.death molecules like Bax was downregulated.Thus, Diosgenin as a plant based steroidal saponin is confirmed to mitigate ischemic reperfusion injury. Figure

Altered membrane integrity has been suggested as a major factor in the development of cellular injury during myocardial necrosis. The present study was designed to investigate the effect of diosgenin on lysosomal hydrolases, membrane-bound enzymes, and electrolytes during isoproterenol (ISO)-induced myocardial necrosis in rats. Animals were pretreated with DIOS (80 mg/kg) for a period of 35 days. Myocardial infarction was experimentally induced with ISO (85 mg/kg) twice at 24 h interval. Experimental myocardial infarction was evidenced with marked elevation of creatine kinase-MB (CK-MB) in serum with concomitant increase in lipid peroxidation (plasma thiobarbituric acid reactive substances (TBARS) and hydroperoxides (HP)). Activity of lysosomal hydrolases (beta-glucuronidase, beta-N-acetyl glucosaminidase, beta-D-galactosidase, cathepsin D, and acid phosphatase) was found to be increased in serum and heart tissue of ISO-alone treated animals. DIOS (80 mg/kg) pretreated groups showed significant decrease in CK-MB, lipid peroxidation, and lysosomal hydrolases activity. The membrane-bound enzymes such as Ca2+-ATPase and Mg2+-ATPase activity was increased and Na+/K+-ATPase activity was decreased in the heart tissues of ISO-alone treated animals. These enzyme alterations lead to the change in the electrolytes content such as sodium, potassium, and calcium in the heart tissue. However, DIOS (80 mg/kg) pretreatment reversed the membrane-bound enzymes activity and thereby maintained the normal electrolyte concentration. These results suggest the protective action of diosgenin in ISO-induced myocardial infarction. The salubrious effect observed in this study might be due to the antioxidant and membrane stabilizing potential of diosgenin.

Isoproterenol is a synthetic catecholamine found to cause toxicity leading to severe stress in the myocardium of experimental animals. The aim of the present study is to evaluate the cardioprotective effect of Cymbopogon citratus, which is used as a culinary item and commonly known as lemon grass (LG), in isoproterenol-induced cardiotoxicity. Male Wistar albino rats were segregated into five different groups as follows. Groups I and II rats were treated with vehicle. Groups III and IV rats were treated with 100 and 200 mg/kg b.wt. of LG. Group V with 100 mg/kg b.wt. of vitamin E. Myocardial necrosis was induced in Groups II, III, IV and V on 58th and 59th day using isoproterenol at a dose of 85 mg/kg twice at 24-hour interval. Animals were sacrificed on the 60 th day. LG pretreatment exhibited cardioprotective activity as evidenced by decreased activity of cardiac markers in serum and increased the same in heart homogenate (p < 0.05). LG administration decreased the toxic events of lipid peroxidation (TBARS) in both serum and heart tissue, by increasing the level of enzymatic antioxidants and non-enzymatic antioxidants significantly in both heart homogenate and serum sample (p < 0.05). The histopathological observations also revealed that the cardioprotective effect of LG extract was observed at a dose of 200 mg/kg b.wt. The results of the present study reveal that LG is cardioprotective and antilipid peroxidative by increasing various antioxidants at a dose of 200 mg/kg b.wt., which is comparable with that of vitamin E.

With recent advances in nutrition sciences, natural products and health-promoting foods have received extensive attention from both health professionals and the common population. The flavonoid rich fraction (FRF) of Dioscorea bulbifera Linn. has a strong free radical scavenging activity. FRF (150 mg/kg) when intervened for a period of 35 days prior to isoproterenol (ISO) challenge to rats maintained the creatine kinase - MB (CK-MB) activity in serum without elevation. Alterations in the antioxidant status in the mitochondria were recognized in the heart tissue of ISO induced rats. ISO induced rats pretreated with FRF (150 mg/kg) ameliorated the lipid peroxidation and thereby enhanced the antioxidant status as evidenced by the increase in the reduced glutathione (GSH) content and the activity of antioxidant enzymes. Moreover, the tricarboxylic acid cycle enzymes such isocitrate dehydrogenase (ICDH), succinate dehydrogenase (SDH), malate dehydrogenase (MDH) and α-ketoglutarate dehydrogenase (α-KGDH), which were found decreased in the ISO induced rats showed an enhanced activity in FRF (150 mg/kg) pretreated rats. The activity of NADH dehydrogenase and cytochrome-C-oxidase the enzymes, which transfer the electron in the electron transport chain (ETC) was also increased significantly (p