AIMTo study whether tacrine and donepezil can prevent cell apoptosis induced by staurosporine in NG108-15 and Hela cell lines.

METHODSMTT assay was used to examine if staurosporine impairs cell metabolism. Phase-contrast and fluorescence microscope were used to examine cell morphological changes. DNA was isolated and electrophoretically separated on 1% agarose gel to observe if there were DNA fragments. Western blot was made to analyse protein levels of anti-apoptotic Bcl-2 and proapoptotic Bax.

RESULTSNG108-15 cells treated with 0.1 mumol.L-1 staurosporine for 12-24 hours exhibited marked cell death and DNA fragmentation. Pre-treatment with 0.1 mmol.L-1 tacrine provided approximately 40% protective effect and resulted in obvious inhibition or delay of DNA fragmentation. Moreover, NG108-15 cells treated with tacrine became elongated and polarized, and showed longer processes than control cells. Pretreatment with 0.1 mmol.L-1 tacrine significantly increased the expression of Bcl-2 protein level and delayed the staurosporine-induced increase of Bax protein expression. However, donepezil did not show any protective effect on the cell impairment induced by staurosporine in NG108-15 cells. In Hela cells 0.1 mumol.L-1 staurosporine also induced significant cell injury, but pretreatment with tacrine and donepezil did not provide any obvious protective effect against this cell damage.

CONCLUSIONDonepezil did not provide obvious protective effect against apoptosis, and protective effects of tacrine might not be mediated through AChE inhibition. Protective effects of tacrine against staurosporine-induced injury might be selective to different cells.