[G-protein-coupled muscarinic acetylcholine receptor activation up-regulates Bcl-2 and phospho-bad via Ras-ERK-1/2 signaling pathway].
Activation of G-protein coupled muscarinic acetylcholine receptors and MAPKs/ERK-1/2 has been found to inhibit neural cell apoptosis and promote neural cell survival. Bcl-2 protein family also plays an important role in regulating neural cell apoptosis and survival. However, signaling pathways coupling muscarinic receptors to Bcl-2 family remains to be elucidated. In the present study, it was found that carbachol not only activated MEK/ERK-1/2 signaling pathways, but also increased the expression levels of Bcl-2 and phospho-Bad proteins in human neuroblastoma SH-SY5Y cells. These effects were blocked by a muscarinic receptor antagonist (atropine) and a MEK inhibitor(PD98059)   and were significantly attenuated by a Src family kinases inhibitor(PP1) and a PKC inhibitor (bisindolymaleimide-I), but were not influenced by a G(i/o)-uncoupling reagent (pertussin toxin) and a PI-3 kinase inhibitor (wortmannin). Furthermore, carbachol also stimulated Bcl-2 promoter-driven luciferase gene expression in transfected SH-SY5Y cells. Co-transfection of Ras or Raf dominant negative mutants with the pBcl-2-Luc plasmid abolished carbachol  s effects. These data suggested that muscarinic acetylcholine receptors regulated the expression of Bcl-2 protein family by Ras-ERK-1/2 signaling pathway involving the pertussin toxin-insensitive G-proteins, PKC and Src.
Li
Jian-Ling
JL
Central Laboratory of Xiang Ya Hospital, Central South University, Changsha 410008, China.
Zhu
Jian-Hua
JH
Jing
Zhao-Zheng
ZZ
Chen
Zhu-Chu
ZC
Xiao
Zhi-Qiang
ZQ
D001285:Atropine / Q000494:pharmacology; D002217:Carbachol / Q000494:pharmacology; D002352:Carrier Proteins / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D008301:Maleimides / Q000494:pharmacology; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010766:Phosphorylation; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D011720:Pyrazoles / Q000494:pharmacology; D011743:Pyrimidines / Q000494:pharmacology; D011976:Receptors, Muscarinic / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D014407:Tumor Cells, Cultured; D015854:Up-Regulation / Q000187:drug effects; D051025:bcl-Associated Death Protein; D018631:ras Proteins / Q000378:metabolism*
C108123:4-amino-5-(4-methylphenyl)-7-(tert-butyl)pyrazolo(3,4-d)pyrimidine; C494819:BAD protein, human; D002352:Carrier Proteins; D004791:Enzyme Inhibitors; D005419:Flavonoids; D007211:Indoles; D008301:Maleimides; D019253:Proto-Oncogene Proteins c-bcl-2; D011720:Pyrazoles; D011743:Pyrimidines; D011976:Receptors, Muscarinic; D051025:bcl-Associated Death Protein; D001285:Atropine; D002217:Carbachol; D011493:Protein Kinase C; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D019204:GTP-Binding Proteins; D018631:ras Proteins; C070515:bisindolylmaleimide I; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one