TRB3 mediates advanced glycation end product-induced apoptosis of pancreatic -cells through the protein kinase C pathway.
Academic Article
Overview
Research
Identity
Additional Document Info
Other
View All
Overview
abstract
Advanced glycation end products(AGEs), which accumulate in the body during the development of diabetes, may be one of the factors leading to pancreatic -cell failure and reduced -cellmass. However, the mechanisms responsible for AGEinduced apoptosis remain unclear. This study identified the role and mechanisms of action of tribbles homolog3(TRB3) in AGE-induced -cell oxidative damage and apoptosis. Rat insulinoma cells(INS-1) were treated with 200g/ml AGEs for 48h, and cell apoptosis was then detected by TUNEL staining and flow cytometry. The level of intracellular reactive oxygen species(ROS) was measured by a fluorescence assay. The expression levels of receptor of AGEs(RAGE), TRB3, protein kinaseC2(PKC2) and nicotinamide adenine dinucleotide phosphate(NADPH) oxidase4(NOX4) were evaluated by RT-qPCR and western blot analysis. siRNA was used to knockdown TRB3expression through lipofection, followed by an analysis of the effects of TRB3 on PKC2 and NOX4. Furthermore, the PKC2-specific inhibitor, LY333531, was used to analyze the effects of PKC2 on ROS levels and apoptosis. We found that AGEs induced the apoptosis of INS-1cells and upregulated RAGE andTRB3expression. AGEs also increased ROS levels in -cells. Following the knockdown of TRB3, the AGE-induced apoptosis and intracellular ROS levels were significantly decreased, suggesting that TRB3 mediated AGE-induced apoptosis. Further experiments demonstrated that the knockdown of TRB3 decreased the PKC2 andNOX4 expression levels. When TRB3 was knocked down, the cells expressed decreased levels of PKC2 and NOX4. The PKC2specific inhibitor, LY333531, also reduced AGE-induced apoptosis and intracellular ROS levels. Taken together, our data suggest that TRB3 mediates AGE-induced oxidative injury in -cells through the PKC2pathway.
