Effects Of Zinc On Preventing Vascular Endothelial Cells From Oxidative Stress

Vascular endothelialcell dysfunction is closely relatedto the occurrence and development of many diseases.Many diseases are early in the presence of vascular endothelial dysfunction,and endothelial cell dysfunction is the beginning and the central link of diabetic vascular complications.Oxidative stress is one of the important causes of diabetic vascular endothelial dysfunction.Oxidative stress has appeares in the abnormal glucose tolerance,meanwhile the abnormal increase in glucose metabolism exacerbates,oxidative stress.Complications of microvascular and macrovascular disease,lead to a significant increase in the incidence and mortality of diabetes.Therefore,finding the right protecting oxidative stress from vascular endothelial cells would be most important drug for the prevention and treatment of cardiovascular complications of diabetes.Zinc（Zn）,as one of the essential trace elements in the human body,has many biological functions.Zn is involved in the synthesis and secretion of insulin,regulating the biological activity and antigenicity of insulin.Therefore,Zn is closely related to the occurrence and development of diabetes and the occurrence of complications.Zn can also act as a cofactor for multipleenzymes and proteins to participate in antioxidant effects.Our previous study has found serum ion disorder in elderly patients with type 2 diabetes,in which zinc ions,magnesium ions in patients with diabetes significantly decreased serum.in the patients,there were serious oxidative damage with endothelial dysfunction.The findings suggest that Zn supplement with diabetics patients,especially elderly diabetic patients,may alleviate diabetes and associate with vascular complications.Therefore,this article aims to study the protective effect of zinc on vascular endothelial cells injured by oxidative stress,and to provide experimental basis and theoretical basis for the prevention and adjuvant treatment of diabetic vascular complications.Objective:To investigate the effects of Zinc sulfate on preventing human umbilical veins endothelial cells（HUVECs）from oxidative stress.Methods:Hydrogen peroxide was used to stimulate HUVECs to build the oxidative stress model in Vitro.HUVECs were divided into normal group,H₂O₂ group,Zinc sulfate group and Zinc sulfate treated group.Nitric oxide（NO）was measured by nitric acid reductase method.The content of endothelin（ET）in the culture medium was determined by enzyme-linked immunosorbent assay（ELISA）.The level of HO-1,SOD and CAT of HUVECs were measured by Western blot.Apoptosis of HUVECs was examined by TUNEL as well.Results:Zinc sulfate could enhance the content of NO and decrease the content of ET in the supernatant,which induced by hydrogen peroxide on HUVECs.Zinc sulfate could also increase the level of HO-1,SOD and CAT obviously and decrease the apoptosis cells significantly induced by H₂O₂ Conclusion:（1）Oxidative stress injury is associated with diabetic endothelial dysfunction.（2）Zinc sulfate can increase the NO content of endothelial cells cultured in vitro,decrease ET content,increase cell HO-1,SOD and CAT levels,reduce oxidative stress-induced apoptosis of endothelial cells.（3）Zinc sulfate can improve the antioxidant capacity ofvascular endothelium,vascular endothelial cell oxidative stress injury have a certain degree of prevention and treatment.