Galpha12 Protects Vascular Endothelial Cells from Serum Withdrawal-Induced Apoptosis through Regulation of miR-155
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Purpose: Apoptosis of vascular endothelial cells is a type of endothelial damage that is associated with the pathogenesis of cardiovasculardiseases such as atherosclerosis. Heterotrimeric GTP-binding proteins (G proteins), including the alpha 12 subunit ofG protein (Gα12), have been found to modulate cellular proliferation, differentiation, and apoptosis of numerous cell types. However,the role of Gα12 in the regulation of apoptosis of vascular cells has not been elucidated. We investigated the role of Gα12 inserum withdrawal-induced apoptosis of human umbilical vein endothelial cells (HUVECs) and its underlying mechanisms. Materials and Methods: HUVECs were transfected with Gα12 small-interfering RNA (siRNA) to knockdown the endogenousGα12 expression and were serum-deprived for 6 h to induce apoptosis. The apoptosis of HUVECs were assessed by Western blottingand terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The expressions of microRNAs were analyzedby quantitative real-time PCR. Results: Knockdown of Gα12 with siRNA augmented the serum withdrawal-induced apoptosis of HUVECs and markedly repressedthe expression of microRNA-155 (miR-155). Serum withdrawal-induced apoptosis of HUVECs was inhibited by the overexpressionof miR-155 and increased significantly due to the inhibition of miR-155. Notably, the elevation of miR-155 expressionprevented increased apoptosis of Gα12-deficient HUVECs. Conclusion: From these results, we conclude that Gα12 protects HUVECs from serum withdrawal-induced apoptosis by retainingmiR-155 expression. This suggests that Gα12 might play a protective role in vascular endothelial cells by regulating the expressionof microRNAs.
Abstract
Purpose: Apoptosis of vascular endothelial cells is a type of endothelial damage that is associated with the pathogenesis of cardiovasculardiseases such as atherosclerosis. Heterotrimeric GTP-binding proteins (G proteins), including the alpha 12 subunit ofG protein (Gα12), have been found to modulate cellular proliferation, differentiation, and apoptosis of numerous cell types. However,the role of Gα12 in the regulation of apoptosis of vascular cells has not been elucidated. We investigated the role of Gα12 inserum withdrawal-induced apoptosis of human umbilical vein endothelial cells (HUVECs) and its underlying mechanisms. Materials and Methods: HUVECs were transfected with Gα12 small-interfering RNA (siRNA) to knockdown the endogenousGα12 expression and were serum-deprived for 6 h to induce apoptosis. The apoptosis of HUVECs were assessed by Western blottingand terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The expressions of microRNAs were analyzedby quantitative real-time PCR. Results: Knockdown of Gα12 with siRNA augmented the serum withdrawal-induced apoptosis of HUVECs and markedly repressedthe expression of microRNA-155 (miR-155). Serum withdrawal-induced apoptosis of HUVECs was inhibited by the overexpressionof miR-155 and increased significantly due to the inhibition of miR-155. Notably, the elevation of miR-155 expressionprevented increased apoptosis of Gα12-deficient HUVECs. Conclusion: From these results, we conclude that Gα12 protects HUVECs from serum withdrawal-induced apoptosis by retainingmiR-155 expression. This suggests that Gα12 might play a protective role in vascular endothelial cells by regulating the expressionof microRNAs.
참고문헌 (24)
- Hepler JR, "G proteins", Trends Biochem Sci, 17, pp.383~387 (1992)
- Xu N, "A mutant alpha subunit of G12 potentiates the eicosanoid pathway and is highly oncogenic in NIH 3T3 cells", Proc Natl Acad Sci U S A, 90, pp.6741~6745 (1993)
- Gan CP, "Heterotrimeric G-protein alpha-12 (Gα12) subunit promotes oral cancer metastasis", Oncotarget, 5, pp.9626~9640 (2014)
- Lu J, "MicroRNA expression profiles classify human cancers", Nature, 435, pp.834~838 (2005)
- Quintavalle M, "Arterial remodeling and atherosclerosis:miRNAs involvement", Vascul Pharmacol, 55, pp.106~110 (2011)
- Ma X, "MicroRNA-155 in the pathogenesis of atherosclerosis: a conflicting role?", Heart Lung Circ, 22, pp.811~818 (2013)
- Yanamadala V, "Heterotrimeric G proteins and apoptosis: intersecting signaling pathways leading to context dependent phenotypes", Curr Mol Med, 9, pp.527~545 (2009)
- Seo M, "Cdc42-dependent mediation of UV-induced p38 activation by G protein betagamma subunits", J Biol Chem, 279, pp.17366~17375 (2004)
- Ro S, "A PCR-based method for detection and quantification of small RNAs", Biochem Biophys Res Commun, 351, pp.756~763 (2006)
- Suárez Y, "Cutting edge: TNF-induced microRNAs regulate TNF-induced expression of E-selectin and intercellular adhesion molecule-1 on human endothelial cells: feedback control of inflammation", J Immunol, 184, pp.21~25 (2010)
- Liu T, "Attenuation of exogenous angiotensin II stress-induced damage and apoptosis in human vascular endothelial cells via microRNA-155 expression", Int J Mol Med, 31, pp.188~196 (2013)
- Goldsmith ZG, "Lysophosphatidic Acid Stimulates the Proliferation of Ovarian Cancer Cells via the gep Proto-Oncogene Gα(12)", Genes Cancer, 2, pp.563~575 (2011)
- Kumar RN, "Proliferation-specific genes activated by Galpha(12): a role for PDG-FRalpha and JAK3 in Galpha(12)-mediated cell proliferation", Cell Biochem Biophys, 41, pp.63~73 (2004)
- Kelly P, "A role for the G12 family of heterotrimeric G proteins in prostate cancer invasion", J Biol Chem, 281, pp.26483~26490 (2006)
- Kelly P, "The G12 family of heterotrimeric G proteins promotes breast cancer invasion and metastasis", Proc Natl Acad Sci U S A, 103, pp.8173~8178 (2006)
- Kim YM, "G(alpha)12", 13 induction of CYR61 in association with arteriosclerotic intimal hyperplasia: effect of sphingosine-1-phosphate, 2011, pp.31, 861~869
- Yanamadala V, "Galpha12 stimulates apoptosis in epithelial cells through JNK1-mediated Bcl-2 degradation and up-regulation of IkappaBalpha", J Biol Chem, 282, pp.24352~24363 (2007)
- Berestetskaya YV, "Regulation of apoptosis by alpha-subunits of G12 and G13 proteins via apoptosis signal-regulating kinase-1", J Biol Chem, 273, pp.27816~27823 (1998)
- Choy JC, "Endothelial cell apoptosis: biochemical characteristics and potential implications for atherosclerosis", J Mol Cell Cardiol, 33, pp.1673~1690 (2001)
- Xu F, "Endothelial cell apoptosis is responsible for the formation of coronary thrombotic atherosclerotic plaques", Tohoku J Exp Med, 218, pp.25~33 (2009)
- Li S, "microRNA-155 silencing inhibits proliferation and migration and induces apoptosis by upregulating BACH1 in renal cancer cells", Mol Med Rep, 5, pp.949~954 (2012)
- Huang RS, "MicroRNA-155 silencing enhances inflammatory response and lipid uptake in oxidized low-density lipoprotein-stimulated human THP-1 macrophages", J Investig Med, 58, pp.961~967 (2010)
- Nazari-Jahantigh M, "MicroRNA-155 promotes atherosclerosis by repressing Bcl6 in macrophages", J Clin Invest, 122, pp.4190~4202 (2012)
- Zhu N, "Endothelial enriched microRNAs regulate angiotensin II-induced endothelial inflammation and migration", Atherosclerosis, 215, pp.286~293 (2011)