Selenium effectively inhibits 1,2-dihydroxynaphthalene-induced apoptosis in human lens epithelial cells through activation of PI3-K/Akt pathway

[摘要] Purpose: To investigate whetheractivation of the phosphatidylinositol 3-kinase (PI3-K)/protein kinaseB (Akt) pathway was necessary for selenium in protecting human lensepithelial cells (hLECs) from 1,2-dihydroxynaphthalene(1,2-DHN)-induced apoptosis. In addition, we studied the link betweenheat shock protein 70 (HSP70) expression and Akt phosphorylation inselenium-induced cell protection. Methods: Cell viabilities were assessedby Cell Counting Kit-8 (CCK-8) kit and trypan blue exclusion. Theeffect of sodium selenite on Akt phosphorylation was studied. After thepretreatment with 30 μM of LY294002, a PI3-K/Akt pathway inhibitor,apoptosis was assessed by flow cytometry, protein levels of phospho-Aktand Akt were quantified by western blot, and cell localization ofphospho-Akt was determined by immunofluorescence staining. Time-courseeffect of sodium selenite on HSP70 expression was studied by reversetranscription polymerase chain reaction (RT–PCR) and western blot.Moreover, effect of LY294002 on HSP70 expression was also examined. Results: Our data showed that sodiumselenite increased cell viabilities and prevented 1,2-DHN-inducedapoptosis through phosphorylation and nuclear translocation of Akt.Furthermore, pretreatment of LY294002 inhibited the phosphorylation ofAkt. However, it failed to block the selenium-induced upregulation ofHSP70. Conclusions: The activation of PI3-K/Aktpathway was necessary for selenium in protecting hLECs from1,2-DHN-induced apoptosis. However, this pathway was not involved inthe selenium-induced upregulation of HSP70.

[学科分类] 生物化学/生物物理