Regulation of SERCA pumps expression in diabetes

•SERCA2a expression and activity are decreased in diabetic cardiomyopathy.•SERCA2b and SERCA3 transport Ca2+ into the ER lumen maintaining resting Ca2+ levels in ß-cells.•Adequate Ca2+ levels are necessary for insulin secretion in ß-cells.•SERCA2b and SERCA3 expression are decreased in ß-cells from diabetic patients.•AGE, ROS and increased O-GlcNAcylation could be involved in SERCA down-regulation.

Cytosolic calcium concentration ([Ca2+]c) is fundamental for regulation of many cellular processes such metabolism, proliferation, muscle contraction, cell signaling and insulin secretion. In resting conditions, the sarco/endoplasmic reticulum (ER/SR) Ca2+ ATPase's (SERCA) transport Ca2+ from the cytosol to the ER or SR lumen, maintaining the resting [Ca2+]c about 25–100 nM. A reduced activity and expression of SERCA2 protein have been described in heart failure and diabetic cardiomyopathy, resulting in an altered Ca2+ handling and cardiac contractility. In the diabetic pancreas, there has been reported reduction in SERCA2b and SERCA3 expression in β-cells, resulting in diminished insulin secretion. Evidence obtained from different diabetes models has suggested a role for advanced glycation end products formation, oxidative stress and increased O-GlcNAcylation in the lowered SERCA2 expression observed in diabetic cardiomyopathy. However, the role of SERCA2 down-regulation in the pathophysiology of diabetes mellitus and diabetic cardiomyopathy is not yet well described. In this review, we make a comprehensive analysis of the current knowledge of the role of the SERCA pumps in the pathophysiology of insulin-dependent diabetes mellitus type 1 (TIDM) and type 2 (T2DM) in the heart and β-cells in the pancreas.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide