Over-expressed Bcl-2 cannot suppress apoptosis via the mitochondria in buprenorphine hydrochloride-treated NG108-15 cells.
We previously reported that the morphine alkaloid derivative buprenorphine hydrochloride (Bph) induces rapid apoptosis in NG108-15 nerve cells accompanied by the activation of caspase-3. Here, we found this kind of apoptosis was also accompanied by rapid loss of the mitochondrial membrane potential, followed by the efflux of cytochrome c from the mitochondria to the cytosol and the activation of caspases-9 and -3. Together, these results strongly suggested the Bph death signal was routed through the mitochondrial pathway in NG108-15 cells. In these cells, serum-starvation induces a different apoptosis, which we exploited to investigate Bcl-2's role as an apoptosis inhibitor. We made an NG108-15 transfectant, Bcl-2(P2), that stably expressed human Bcl-2, and used it to test Bcl-2's effect on the serum-starvation-induced apoptosis in NG108-15 cells. Cell viability, DNA-ladder formation, and efflux of cytochrome c from the mitochondria were all detected, showing that the human Bcl-2 functioned normally in the Bcl-2(P2) cells. Although the apoptotic events tested were identical in the parental cells and transformants, Bcl-2 expression completely failed to inhibit Bph-induced apoptosis in the Bcl-2(P2) cells.
Kugawa
Fumihiko
F
Department of Biological Pharmaceutical Sciences, College of Pharmacy, Nihon University, 7-7-1 Narashino-dai, Funabashi, Chiba 274-8555, Japan. jfkugawa@pha.nihon-u.ac.jp
Nakamura
Maiko
M
Ueno
Akemichi
A
Aoki
Masatada
M
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002047:Buprenorphine / Q000494:pharmacology*; D045744:Cell Line, Tumor / Q000187:drug effects; D005786:Gene Expression Regulation; D019254:Genes, bcl-2 / Q000187:drug effects; D006822:Hybrid Cells; D007425:Intracellular Membranes / Q000378:metabolism; D008564:Membrane Potentials / Q000187:drug effects; D008928:Mitochondria / Q000378:metabolism / Q000502:physiology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis / Q000502:physiology*
D019253:Proto-Oncogene Proteins c-bcl-2; D002047:Buprenorphine