MCU and Hyperglycemia: MCU is a mitochondrial inner membrane uniporter that mediates mitochondrial uptake of Ca2+ and controls its concentration within this organelle.20 Previous studies have shown that excessive mitochondrial Ca2+ uptake has deleterious effects, including ROS overproduction,21 sensitization to apoptosis,22 and activation of the permeability transition pore and subsequent cell death pathways.23,24 Our results demonstrate that hyperglycaemia results in increased MCU expression and impaired cell function.