VEGF165 reduced apoptosis by regulation of CaSR expression in ischemia/reperfusion cardiomyocytes

Abstract

Abstract: AIM: To examine whether anti-apoptotic role of VEGF165 is associated with downregulation of CaSR expression in ischemia/reperfusion cardiomyocytes.METHODS: We incubated primary neonatal rat ventricular cardiomyocytes in ischemia-mimetic solution for 2 h, then re-incubated them in normal culture medium for 24 h to establish a model of simulated ischemia/reperfusion(I/R). Cardiomyocyte apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). The expression of CaSR mRNA was detected by RT-PCR. In addition, the expressions of Bax and Bcl-2 were analyzed by Western blot.RESULTS: The simulated I/R enhanced the expression of CaSR(I/R group:2.6±0.4;control group:1.0±0.3, P<0.01)and TUNEL-positive cardiomyocytes(I/R group:15.3%±2.5%;control group:2.9%±1.4%,P<0.01). GdCl₃, a specific activator of CaSR, further increased the expression of CaSR (GdCl₃ group:4.5±0.6;I/R group:2.6±0.4, P<0.01)and TUNEL-positive cardiomyocytes(GdCl₃ group:25.4%±2.6%;I/R group:15.3%±2.5%, P<0.01), along with upregulation of Bax (GdCl₃ group:1.93±0.28;I/R group:1.50±0.21, P<0.01)and downregulation of Bcl-2(GdCl₃ group:0.82±0.18;I/R group:1.71±0.30, P<0.01). Treatment of VEGF165 decreased I/R- and GdCl₃-induced CaSR(GdCl₃+ VEGF165 group:1.46±0.37;GdCl₃ group:4.46±0.62, P<0.01), Bax expression (GdCl₃+ VEGF165 group:1.12±0.23;GdCl₃ group:1.93±0.28, P<0.05), TUNEL-positive cardiomyocytes (GdCl₃+VEGF165 group:11.8%±1.9%;GdCl₃ group:25.4%±2.6%, P<0.05)and increased Bcl-2 expression(GdCl₃+ VEGF165 group: 2.56±0.54;GdCl₃ group:0.82±0.18, P<0.05).CONCLUSION: VEGF165 decrease cardiomyocyte apoptosis induced with I/R by inhibiting CaSR and Bax, promoting Bcl-2 expression.

Key words: VEGF165, CaSR, Apoptosis, Cardiomyocyte, Ischemia/reperfusion

CLC Number:

R965.2

ZHANG Bin, XU Zhi-hui, TAO Zheng-xian. VEGF165 reduced apoptosis by regulation of CaSR expression in ischemia/reperfusion cardiomyocytes[J]. Chinese Journal of Clinical Pharmacology and Therapeutics, 2011, 16(1): 26-32.

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