[Effect of arsenic pentaoxide on proliferation and apoptosis of human umbilical vein endothelial cell].

OBJECTIVE: To investigate the effects of arsenic pentaoxide (As2O5) on the proliferation and apoptosis of endothelial cells and compare the effect of As2O5 and arsenic trioxide (As2O3) in vitro. METHODS: Human umbilical vein endothelial cells (HUVEC) were incubated with or without As2O5 or As2O3 for a certain period. The proliferation profile of HUVEC was determined by methyl thiazolyl tetrazolium (MTT) method. The apoptosis of HUVEC was detected by microscopy and flow cytometry (FCM). RESULTS: As shown by MTT assay, the viabilities of HUVEC were (72.5 +/- 13.8)%, (52.9 +/- 6.2)%, (15.0 +/- 12.8)%, and (13.8 +/- 13.2)%, respectively, in 0.5, 1.0, 5.0, and 10.0 mg/L As2O5 groups, of which the viabilities of HUVEC at 1.0, 5.0, and 10.0 mg/L of As2O5 were significantly lower than controls (P = 0.006, 0.007, and 0.008); however, the viability was not significantly different between 5.0 and 10.0 mg/L As2O5 groups (P = 0.119). In 1.0 mg/L As2O5 group, the cell viabilities were (88.4 +/- 6.3)%, (53.1 +/- 8.8)%, (30.7 +/- 7.9)%, and (16.3 +/- 4.6)%, respectively, at 24, 48, 72, and 96 h, of which the cell viabilities at 48, 72, and 96 h were significantly lower than controls (P = 0.042, 0.025, and 0.012). As2O5-induced apoptosis of HUVEC was observed by phase contrast microscope and flow cytometry with Annexin V/PI staining. After 48 hours of incubation, the IC50s of As2O5 and As2O3 were 1.1 and 0.3 mg/L, respectively. CONCLUSIONS: As2O5 can inhibit the proliferation of HUVEC and the minimum effective concentration is 1 mg/L. Apoptosis is the main way that As2O5 induces the death of HUVEC. The inhibitory effect of As2O5 on HUVEC is weaker than that of As2O3.