Journal Article

Anti-hypoxic effect of ginsenoside Rbl on neonatal rat cardio- myocytes is mediated through the specific activation of glucose transporter-4 ex vivo

Hong-liang KONG Jian-ping WANG Zhan-quan LI Shu-mei ZHAO Jing DONG Wei-wei ZHANG

2009

Overview

Aim： The aim of this study was to investigate whether Gs-Rbl relieves the CoC12-induced apoptosis of hypoxic neonatal rat cardiomyocytes and in which the role of glucose transporter-4 （GLUT-4）. Methods： Gs-Rbl （0, 10, 50, 100, 200, 400, and 500 μmol/L）, adenine 9-β-D-arabinofuranoside （ara A, 500 μmol/L; AMPK inhibitor） and wortmannin （0.5μmol/L; PI3K inhibitor） only in combination with 200 μmol/L Gs-Rbl were administered in hypoxic cardiomyocytes, which were induced by 500μmol/L COCl2 for 12 h. Then, the apoptotic rate （AR）, 2-[3H]-deoxy- D-glucose （2-[3H]-DG） uptake, and the expression of GLUT-4 （including in plasma membrane, PM）, phospho-AMPKa （Thr172）, AMPKa and Akt in cells were assayed. Results： Compared with simple hypoxia （0μmol/L Gs-Rbl）, Gs-Rbl greater than 10μmol/L significantly decreased the apoptotic rate （P〈0.01） and significantly increased 2-[3H]-DG uptake （P〈0.01）, GLUT-4 content in cells and PM （P〈0.01）, AMPK activity （P〈0.01） and Akt （P〈0.01） levels in a dose-dependent manner. AMPK activity was completely suppressed by ara-A, just as Akt was suppressed by wortmannin. The AR, glucose uptake and GLUT-4 levels in cells and PM were partly down-regulated by ara-A or wortmannin. Conclusion： Gs-Rbl may protect neonatal rat cardiomyocytes from apoptosis induced by CoCl2. The anti-apoptotic effect of Gs-Rbl may occur by improving glucose uptake, in which GLUT-4 translocation and expression played a key role. Both the AMPK and the PI3K/Akt pathways may take part in the anti-hypoxic efficacy of Gs-Rbl.

• Subject: PI3K/Akt / wortmannin / 人参皂甙 / 保护心肌细胞 / 抗缺氧作用 / 新生大鼠 / 细胞凋亡率 / 葡萄糖转运体4