RESUMO
Lipid peroxidation by ROS at the membrane level disturbs the inherit integrity of components activating subsequent alterations in the function. In this study, the protective effect of purified Sundakai (Solanum torvum) seed protein (SP) was tested against oxidative membrane damage in erythrocyte membrane. SP prevented oxidative RBC lysis induced by pro-oxidants; Fe:As (2:20 µmol), periodate (0.4 mM), and t-BOOH (1 mM) up to 86, 81, and 86 %, respectively. Further, SP prevented the Fe:As-induced K(+) leakage up to the tune of 95 %. The inhibition offered by SP on K(+) leakage was comparable to inhibition offered by quinine sulfate, a known K(+) channel blocker. SP dose dependently restored Na(+)K(+) ATPase and Ca(2+)Mg(2+) ATPase activities in erythrocyte membrane. The restoration of ATPase activity by SP was two times more than standard antioxidants BHA and α-tocopherol. Besides, SP at 1.6 µmol restored the membrane proteins over Fe:As induction when analyzed by SDS-PAGE, which was comparable to protection offered by BHA. In conclusion, SP is an effective antioxidant in preventing oxidative membrane damage and associated functions mediated by ROS. As SP is non-toxic, it can be used as an effective bioprotective antioxidant agent to cellular components.
Assuntos
Antioxidantes/farmacologia , Membrana Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteínas de Plantas/farmacologia , Substâncias Protetoras/farmacologia , Sementes/química , Solanum/química , ATPase de Ca(2+) e Mg(2+)/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eritrócitos/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Oxirredução/efeitos dos fármacos , Potássio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismoRESUMO
Organic fuel smoke is a hazardous agent, which pushes the cells towards"prooxidant state'', leading to 4,46,400 strand breaks/cell/day as against 47,000 strand breaks/cell/day produced by constitutive oxygen radicals. This prooxidants scenario switches on a plethora of intercellular events. Here we report a novel DNA damaging factor released by lymphocytes, upon treatment with smoke condensate. Human lymphocytes, when exposed to cow dung cake smoke condensate, were found to release a low molecular weight factor into the media at 20 min of exposure. The conditioned media, displayed a propensity of inducing DNA damage in fresh, normal lymphocytes, which were not exposed to any damaging agent. The above DNA damaging effect of the conditioned media was not due to any residual presence of Polycyclic Aromatic Hydrocarbons, which were present in the smoke. The release of this factor was in correlation with the DNA damaging event, taking place in the cells. This secondary DNA damaging factor had a molecular weight less than 5 kd. The factor had the cell death inducing propensity when allowed to act on lymphocytes.