Pro-apoptotic effect of endogenous H2S on human aorta smooth muscle cells.
Cystathionine gamma-lyase (CSE) is a key enzyme in the trans-sulfuration pathway, which uses L-cysteine to produce hydrogen sulfide (H2S). The CSE/H2S system has been shown to play an important role in regulating cellular functions in different systems. In the present study, we overexpressed CSE in human aorta smooth muscle cells (HASMCs) using a recombinant defective adenovirus containing CSE gene (Ad-CSE). Infection of HASMCs with Ad-CSE resulted in a significant increase in the expression of CSE protein and H2S production. Ad-CSE transfection inhibited cell growth and stimulated apoptosis, as evidenced by cell viability assay, Hoechst 33258 staining, TUNEL, and caspase 3 activation. CSE-mediated apoptosis was associated with an increased ERK and p38 MAPK activation, up-regulation of p21(Cip/WAK-1), and down-regulation of cyclin D1 expression. After inhibiting endogenous background CSE gene expression, direct administration of H2S at 100 microM induced apoptosis of HASMCs. The other two endproducts of CSE-catalyzed enzymatic reaction, ammonium and pyruvate, failed to do so. These results demonstrate that overexpression of CSE stimulates SMC apoptosis due to an increased endogenous production of H2S. Adenovirus-mediated transfer of CSE gene may provide a novel therapeutic approach in treating vascular diseases linked to abnormal cellular proliferation and vascular remodeling.
Yang
Guangdong
G
Department of Physiology, College of Medicine, University of Saskatchewan, Saskatoon, Canada.
Wu
Lingyun
L
Wang
Rui
R
D001011:Aorta; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000096:biosynthesis / Q000235:genetics; D002455:Cell Division; D002478:Cells, Cultured / Q000166:cytology / Q000187:drug effects; D019938:Cyclin D1 / Q000096:biosynthesis / Q000235:genetics; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000096:biosynthesis / Q000235:genetics; D003542:Cystathionine gamma-Lyase / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D005822:Genetic Vectors / Q000235:genetics / Q000494:pharmacology; D006801:Humans; D006862:Hydrogen Sulfide / Q000378:metabolism* / Q000494:pharmacology; D020935:MAP Kinase Signaling System / Q000235:genetics; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000502:physiology*; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000187:drug effects*; D034741:RNA, Small Interfering / Q000494:pharmacology; D011993:Recombinant Fusion Proteins / Q000502:physiology; D014161:Transduction, Genetic; D014162:Transfection
C493956:CDKN1A protein, human; D018797:Cell Cycle Proteins; D050759:Cyclin-Dependent Kinase Inhibitor p21; D034741:RNA, Small Interfering; D011993:Recombinant Fusion Proteins; D019938:Cyclin D1; D003542:Cystathionine gamma-Lyase; D006862:Hydrogen Sulfide