Protective effect of 17-β-estradiol on the cultured human umbilical vein endothelial cells damaged by hypoxia.

Objective To explore the effects of hypoxia on cultured human umbilical vein endothelial cells (HUVECs) and investigate the protective role of 17-β-estradiol (E_2 ) in this injury. Methods The primary cultures of HUVECs were harvested by trypsin. The hypoxic cell model was established. Five groups were randomly divided: control, hypoxic 12h, hypoxic 24h, E_2+hypoxic 12h, E_2+hypoxic 24h. The control cells were cultured under normoxia, hypoxic group were cultured under hypoxia, E_2+hypoxic group: 17-β-estradiol were added into before hypoxic culture. The culture fluid were collected for measuring nitric oxide (NO) and endothelin (ET-1) respectively by Griess reaction and radioimmunoassay. The HUVECs were subjected to cell counting and cytoskeleton staining. Results After cultured under hypoxic condition for 12h, the endothelial cells (ECs) counting decreased from (4.33±0.24)×106/ml in the control group to ( 3.23± 0.21)×106/ml(P0.01), NO also decreased from (19.28±2.08)nmol/106cell to(12.77±1.90) nmol/106cell(P 0.01), but the ET-1 increased from( 95.7±11.32 )pg/ml to (138.3±10.37 )pg/ml(P0.01), the cells didn't appear significant morphy change. After cultured under hypoxic condition for 24h, the ECs counting decreased from (4.33± 0.24)×106/ml in the control group to(2.73±0.19)×106/ml (P0.01), NO also decreased from (19.28±2.08)nmol/106cell to(10.76±1.57)nmol/106cell(P0.01), but the ET-1 increased from( 95.7±11.32)pg/ml to (150.1± 15.41)pg/ml(P0.01), the cells appeared longer morphy and smaller volume. After pretreated with 17-β-estradiol, these changes were markedly inhibited(P0.01). Conclusion The structure and function of HUVECs are damaged during hypoxia and 17-β-estradiol has a protective role for this injury.