Peroxiredoxin 1 plays a primary role in protecting pancreatic ß-cells from hydrogen peroxide and peroxynitrite.

Peroxiredoxin 1 plays a primary role in protecting pancreatic ß-cells from hydrogen peroxide and peroxynitrite. Am J Physiol Regul Integr Comp Physiol. 2020 Apr 15;: Authors: Stancill JS, Happ JT, Broniowska KA, Hogg N, Corbett JA Abstract Both reactive nitrogen and oxygen species (RNS and ROS) such as nitric oxide, peroxynitrite, and hydrogen peroxide have been implicated as mediators of pancreatic ß-cell damage during the pathogenesis of autoimmune diabetes. While ß-cells are thought to be vulnerable to oxidative damage due to reportedly low levels of antioxidant enzymes such as catalase and glutathione peroxidase, we have shown that they use thioredoxin reductase to detoxify hydrogen peroxide. Thioredoxin reductase is an enzyme that participates in the peroxiredoxin antioxidant cycle. Peroxiredoxins are expressed in ß-cells and, when overexpressed, protect against oxidative stress, but the endogenous roles of peroxiredoxins in the protection of ß-cells from oxidative damage are unclear. Here, using either glucose oxidase or menadione to continuously deliver hydrogen peroxide, or the combination of DPTA/NO and menadione to continuously deliver peroxynitrite, we tested the hypothesis that b-cells use peroxiredoxins to detoxify both of these reactive species. Either pharmacological inhibition with peroxiredoxin inhibitor conoidin A or specific depletion of cytoplasmic peroxiredoxin 1 (Prdx1) using siRNAs sensitizes INS 832/13 ce...
Source: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology - Category: Physiology Authors: Tags: Am J Physiol Regul Integr Comp Physiol Source Type: research