Zinc supplement modulates oxidative stress and antioxidant values in rats with severe acute pancreatitis.

Oxidative stress is a main factor in the pathogenesis of severe acute pancreatitis (SAP). The ability of zinc (Zn) to retard oxidative processes has been recognized for many years. This study aims to examine the levels of free oxygen radicals and antioxidant enzyme in SAP rats and know the effect of Zn supplementation on free oxygen radicals and antioxidant system in rats with SAP. Forty-five male Wistar rats were divided into three groups-the SAP group (n=15), the Zn-treated group (n=15), and the controlled group (n=15). For the SAP group, sodium taurocholate is injected into the pancreatic duct to induce SAP; for the Zn-treated group, Zn (5 mg/kg) is subcutaneously injected immediately after injection of 5% sodium taurocholate. Firstly, the activity of erythrocyte glutathione peroxidase (GSH-Px), erythrocyte superoxide dismutase (SOD), and the content of plasma malondialdehyde (MDA), which are the toxic products of oxidative stress, is measured. Secondly, the levels of free oxygen radicals in the liver and kidney are detected. The result showed that the activity of GSH-Px and SOD was lower in the SAP group than that in the controlled group, although the content of plasma MDA increased. However, the activity of SOD and GSH-Px in the Zn-treated group was not significantly decreased after comparing with the controlled group; in the mean time, the content of MDA was not significantly increased either. Moreover, the content of free radical in liver and kidney was higher in the SAP group compared with the controlled group, but the content of free radical in the Zn-treated group was not higher than that in the controlled group (p>0.05). All of the above indicated that Zn may recover the activity of free radical-scavenging enzymes and decrease the content of free radical for the SAP group rats. In conclusion, the content of free radical increase may be one of the reasons that SAP rats are injured, and it is possible for Zn to be used to treat SAP through scavenging free radical and increasing the activity of SOD and GSH-Px of erythrocyte.