Proteomic research of human retinal microvascular pericytes stimulated with high glucose

Objective To determine the changes of protein expressions in human retinal microvascular pericytes (HRMPCs) stimulated with high glucose by using quantitative proteomics, which provides new clues for future investigation of diabetic retinopathy (DR). Methods HRMPCs were divided into two groups.The cells in control group were cultured in DMEM basic medium with 25 mmol/L glucose, while the cells in high glucose group were cultured in DMEM medium with 35 mmol/L glucose.The amount of living cells was measured by cell counting kit-8(CCK-8). The proteins were collected from the two groups and then were digested with trypsin.Peptides of 2 μg were injected into the time of flight-mass spectrometer and the acquisition mode was DDA.The results were further analyzed using bioinformatics software. Results CCK-8 results showed that the absorbance (A450) of HRMPCs in high glucose group was 0.75±0.04, which was significantly lower than 0.91±0.05 in control group (t=5.784, P=0.000 2). In total, 1 972 proteins were identified and 54 of them were significantly different between the two groups (fold change >1.5). Among them, 13 proteins were up-regulated, including CTNNB1 and CTBP2; while 41 proteins were down-regulated, including SQSTM1 and HMGCS1.The differentially expressed proteins were mainly involved in citric acid cycle and aerobic respiration. Conclusions The expressions of many proteins in HRMPCs change under the stimulation of high glucose, which may influence the respiration and the ATP production of cells and eventually induce the loss of pericyte. Key words: Diabetic retinopathy; Proteomics; Human retinal microvascular pericyte