AIM:To evaluate cell proliferation, apoptosis and migration of human retinal pigment epithelial cells(RPE)when co-cultured with human marrow mesenchymal stem cells(hMSCs)in condition of hypoxia and hyperglycemia so as to explore possible mechanisms of diabetes aggravating choroidal neovascularization(CNV)preliminarily.

METHODS:Both hMSCs and RPE cells were co-cultured in a transwell system. The experiment was divided into four groups: 21% O₂ with 5.56mmol/L glucose(control group, A), 21% O₂ with 30mmol/L glucose(hyperglycemia and normoxia group, B), 5% O₂ with 5.56mmol/L glucose(normoglycemia and hypoxia group, C)and 5% O₂ with 30mmol/L glucose(hyperglycemia and hypoxia group, D). Cell Counting Kit-8(CCK-8)was used to detect the proliferation of RPE cells in each group at 12, 24 and 48h respectively. Flow cytometry was performed to observe apoptosis of RPE cells at 24h. Additionally, we assessed migration capabilities of RPE via transwell assay under the condition of hyperglycemia and hypoxia by co-culturing of hMSCs.

RESULTS:In this co-culturing system, at 12, 24 and 48h, group B(1.61±0.41, 1.80±0.34; 1.91±0.35), C(1.34±0.46, 1.94±0.40, 2.14±0.41)and D(1.98±0.47, 2.26±0.42, 2.55±0.40)showed significantly higher proliferation rate than group A(0.92±0.45, 1.27±0.32, 1.59±0.41, P<0.05). The migration capabilities of RPE in group B(149.5±9.19), C(140±9.90)and D(170.5±7.78)increased dramatically compared with group A(114.5±7.78, P<0.05)at 24h, whereas there was no significant difference of apoptosis ratio among four groups(P>0.05).

CONCLUSION:By coexistence with hMSCs, the synergy of hyperglycemia and hypoxia can improve migration and proliferation of RPE cells, and have no effect on apoptosis of RPE cells within short period.