Department of Neurosurgery, The Third Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China.
Department of Urology, The Fourth Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, P.R. China.
Int J Mol Med. 2014 Apr;33(4):987-93. doi: 10.3892/ijmm.2014.1660. Epub 2014 Feb 17.
In a previous study, we reported that resveratrol exerts antitumor effects through the estrogen receptor in prolactinoma. The autophagy/lysosomal degradation pathway plays an important role in damage control and energy efficiency. In this study, we investigated the involvement of autophagy and the related signaling pathways in resveratrol-induced apoptosis of GH3 cells. We demonstrate that resveratrol inhibits cell proliferation and induces apoptosis in a dose-dependent manner in GH3 cells. The cleavage of PARP was also observed, and the activation of caspase-3 and caspase-8 was detected. Consistent with this finding, the inhibition of caspase activation effectively attenuated resveratrol-induced cell apoptosis. In addition, the decreased level of Bcl-2 was also observed. The induction of autophagy was confirmed by the detection of the formation of autophagic vacuoles, and the increase in microtubule-associated protein 1 light chain 3 (LC3)-II and beclin-1 levels, two hallmarks of autophagy. Pre-treatment with bafilomycin A1 or 3-methyladenine, inhibitors of autophagy, enhanced the resveratrol-mediated caspase activation and cell death. Moreover, resveratrol induced the activation of ERK1/2, as well as the downregulation of Akt and mTOR phosphorylation. Taken together, these findings indicate that resveratrol induces caspase-dependent apoptosis and decreases Bcl-2 levels. In addition, resveratrol-induced autophagy is regulated by the PI3K/Akt/mTOR and ERK1/2 pathways. Furthermore, the inhibition of autophagy increases the cytotoxicity of resveratrol to GH3 cells.
在之前的研究中，我们报道白藜芦醇通过催乳素瘤中的雌激素受体发挥抗肿瘤作用。自噬/溶酶体降解途径在损伤控制和能量效率方面起着重要作用。在这项研究中，我们研究了自噬及其相关信号通路在白藜芦醇诱导 GH3 细胞凋亡中的作用。我们证明白藜芦醇以剂量依赖性方式抑制 GH3 细胞的增殖并诱导其凋亡。还观察到 PARP 的裂解，并且检测到 caspase-3 和 caspase-8 的激活。与这一发现一致，抑制半胱天冬酶激活有效地减弱了白藜芦醇诱导的细胞凋亡。此外，还观察到 Bcl-2 水平降低。通过检测自噬小体的形成以及微管相关蛋白 1 轻链 3（LC3）-II 和 beclin-1 水平的增加来确认自噬的诱导，这是自噬的两个标志。用巴弗洛霉素 A1 或 3-甲基腺嘌呤（自噬的抑制剂）预处理增强了白藜芦醇介导的半胱天冬酶激活和细胞死亡。此外，白藜芦醇诱导 ERK1/2 的激活以及 Akt 和 mTOR 磷酸化的下调。综上所述，这些发现表明白藜芦醇诱导 caspase 依赖性凋亡并降低 Bcl-2 水平。此外，白藜芦醇诱导的自噬受 PI3K/Akt/mTOR 和 ERK1/2 途径的调节。此外，自噬的抑制增加了白藜芦醇对 GH3 细胞的细胞毒性。
