School of Life Science, Sichuan University, Chengdu, Sichuan, China.
Horm Metab Res. 2012 Jan;44(1):33-40. doi: 10.1055/s-0031-1295416. Epub 2011 Dec 28.
The present study was designed to determine the antihyperglycemic function of ginsenoside Rh2 (GS-Rh2) by the regeneration of β-cells in mice that underwent 70% partial pancreatectomy (PPx), and to explore the mechanisms of GS-Rh2-induced β-cell proliferation. Adult C57BL/6J mice were subjected to PPx or a sham operation. Within 14 days post-PPx, mice that underwent PPx received GS-Rh2 (1 mg/kg body weight) or saline injection. GS-Rh2-treated mice exhibited an improved glycemia and glucose tolerance, an increased serum insulin levels, and β-cell hyperplasia. Meanwhile, increased β-cell proliferation percentages and decreased β-cell apoptosis percentages were also observed in GS-Rh2-treated mice. Further studies on the Akt/Foxo1/PDX-1 signaling pathway revealed that GS-Rh2 probably induced β-cell proliferation via activation of Akt and PDX-1 and inactivation of Foxo1. Studies on the abundance and activity of cell cycle proteins suggested that GS-Rh2-induced β-cell proliferation may ultimately be achieved through the regulation of cell cycle proteins. These findings demonstrate that GS-Rh2 administration could inhibit the tendency of apoptosis, and reverse the impaired β-cell growth potential by modulating Akt/Foxo1/PDX-1 signaling pathway and regulating cell cycle proteins. Induction of islet β-cell proliferation by GS-Rh2 suggests its therapeutic potential in the treatment of diabetes.
本研究旨在通过在接受 70%部分胰切除术 (PPx) 的小鼠中β细胞的再生来确定人参皂苷 Rh2 (GS-Rh2) 的抗高血糖功能,并探讨 GS-Rh2 诱导β细胞增殖的机制。成年 C57BL/6J 小鼠接受 PPx 或假手术。在 PPx 后 14 天内,接受 PPx 的小鼠接受 GS-Rh2 (1 mg/kg 体重) 或生理盐水注射。GS-Rh2 治疗的小鼠表现出改善的血糖和葡萄糖耐量、血清胰岛素水平升高和β细胞增生。同时,在 GS-Rh2 治疗的小鼠中也观察到β细胞增殖百分比增加和β细胞凋亡百分比降低。对 Akt/Foxo1/PDX-1 信号通路的进一步研究表明,GS-Rh2 可能通过激活 Akt 和 PDX-1 以及失活 Foxo1 来诱导β细胞增殖。对细胞周期蛋白丰度和活性的研究表明,GS-Rh2 诱导的β细胞增殖可能最终通过调节细胞周期蛋白来实现。这些发现表明,GS-Rh2 给药可通过调节 Akt/Foxo1/PDX-1 信号通路和调节细胞周期蛋白来抑制细胞凋亡趋势并逆转受损的β细胞生长潜力。GS-Rh2 诱导胰岛β细胞增殖表明其在糖尿病治疗中的潜在治疗作用。