隐丹参酮对高糖损伤大鼠视网膜微血管内皮细胞的保护作用及机制研究OA

Objective To investigate the protective effect of cryptotanshinone(CTS)against high-glucose(HG)-induced injury in primary rat retinal capillary endothelial cells(RCECs)by examining the NOX4/ROS axis and the intracellular antioxidant system.Methods Primary RCECs isolated from Sprague-Dawley(SD)rats were cultured by collagenase-Ⅱ digestion and gelatin adherence.Cells were randomly divided into normal glucose group(with 5.5 mmol/L glucose),high glucose group(with 30 mmol/L glucose),and 5 high glucose plus CTS groups(with 30 mmol/L glucose+0.5,1,2,and 5 µmol/L CTS)for 72 hours intervention.Cell viability was measured by MTT assay;intracellular ROS was detected with fluorescent probe(DCFH-DA)combined with laser scanning confocal microscopy;activities of superoxide dismutase(SOD),catalase(CAT)and glutathione peroxidase(GSH-Px),contents of malondialdehyde(MDA)and reduced/oxidized glutathione(GSH/GSSG)were determined by colorimetric method;protein expression of NADPH oxidase 4(NOX4)was analyzed by Western blot.Results Compared with normal glucose group,high glucose group showed markedly decreased cell viability(P<0.01),increased ROS(P<0.01)and MDA levels(P<0.01);the activities of SOD,CAT and GSH-Px were decreased,GSH/GSSG ratio was reduced(P<0.01),and NOX4 expression was up-regulated(P<0.01).Compare with high glucose group,high glucose plus CTS groups recovered cell viability,restored cell viability,reduced ROS generation,enhanced antioxidant capacity,alleviated lipid peroxidation,and down-regulated NOX4(P<0.05).Conclusion CTS protects RCECs in rats from HG-induced oxidative damage by inhibiting NOX4-mediated ROS overproduction and reinforcing the intracellular antioxidant defence system,offering a potential natural small-molecule strategy for early diabetic retinopathy.