AIM: To investigate the angiogenesis effect and protective mechanism of cordycepin on rhesus macaque choroid-retinal endothelial(RF/6A)cell line cultured in high glucose condition.

METHODS: Cultured RF/6A cells were divided into normal control group, high glucose group and high glucose(HG)+ different concentration cordycepin groups(HG+10μg/mL group, HG+50μg/mL group, HG+100μg/mL group). The cell proliferation was assessed using cholecystokinin octapeptide dye after treated for 48h. The cell migration was investigated by a Transwell assay. The tube formation was measured on Matrigel. Furthermore, the impact of cordycepin on high glucose-induced activation of VEGF and VEGF receptor 2(VEGFR-2)was tested by Western blot analysis.

RESULTS: Compared with normal control group, cell viability markedly increased in high glucose group(P<0.05). Cordycepin inhibited RF/6A cell proliferation in a dose-dependent fashion: 10.2±0.9%, 23.4±1.5% and 31.1±1.2% inhibition as the concentrations of cordycepin were 10, 50 and 100μg/mL, respectively. The difference had statistically significant(P<0.05)compared with high glucose group. The number of cell migration were 55.6±2.70, 87.4±2.40, 65.4±2.7, 57.8±2.38, 62.4±2.77 in normal control group, high glucose group and HG+10μg/mL group, HG+50μg/mL group, HG+100μg/mL group respectively. Migration of RF/6A conspicuously increased in high glucose group(P<0.05)compared with normal control group; while showing a gradually reducing trend with the increase of cordycepin dose and a statistically significant difference compared with high glucose group(P<0.05). The number of tube formation were 18.7±2.08, 25.7±1.52, 19.9±1.57, 16.3± 2.51, 5.67±1.72 in the abovementioned group. Similarly showing a gradually reducing trend with the increase of cordycepin dose and a statistically significant difference with high glucose group(P<0.05). In addition, the number of tube formation of RF/6A in high glucose group significant increased compared with normal control group(P<0.05). The expression of VEGF and VEGFR-2 dramaticlly increased in high glucose group vs normal control group, oppositely gradually decreased with the increase of cordycepin concentrations, and had a statistically significant difference vs high glucose group(P<0.05).

CONCLUSION: Cordycepin can suppress the proliferation, migration and tubu formation of RF/6A in high glucose condition, might via inhibiting expression of VEGF and VEGFR-2.