Department of Microbiology, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand.
J Proteome Res. 2010 May 7;9(5):2076-86. doi: 10.1021/pr100049v.
Beta-amyloid (A beta) plays a key role in the pathogenesis of Alzheimer's disease (AD) by inducing neurotoxicity and cell death mainly through production of reactive oxygen species (ROS). Garcinia mangostana L. (mangosteen) has been recognized as a major source of natural antioxidants that could decrease ROS. However, its role in protection of A beta-induced cytotoxicity and apoptosis in neuronal cells remains unclear. We therefore examined such a protective effect of mangosteen extract (ME) by evaluating cell viability using MTT test, ROS level, caspase-3 activity, and cellular proteome. Treating SK-N-SH cells with 5-20 microM A beta((1-42)) for 24 h caused morphologically cytotoxic changes, decreased cell viability and increased ROS level, whereas preincubation with 50-400 microg/mL ME 30 min before the induction by A beta((1-42)) successfully prevented such cytotoxic effects in a dose-dependent manner (completely at 400 microg/mL). The A beta-induced increase in caspase-3 activity was also preventable by 400 microg/mL ME. Proteomic analysis using 2-D gel electrophoresis (n = 5 gels/group) followed by mass spectrometry revealed 63 proteins whose levels were significantly altered by A beta((1-42)) induction. Interestingly, changes in 10 proteins were successfully prevented by the ME pretreatment. In summary, we report herein the significant protective effects of ME against A beta-induced cytotoxicity, increased ROS, and increased caspase activity in SK-N-SH cells. Moreover, proteomic analysis revealed some proteins that might be responsible for these protective effects by ME. Further characterizations of these proteins may lead to identification of novel therapeutic targets for successful prevention and/or decreasing the severity of AD.
β-淀粉样蛋白（Aβ）通过产生活性氧物种（ROS）诱导神经毒性和细胞死亡，在阿尔茨海默病（AD）的发病机制中起关键作用。藤黄果（山竹）已被公认为天然抗氧化剂的主要来源，可减少 ROS。然而，其在保护神经元细胞免受 Aβ诱导的细胞毒性和细胞凋亡中的作用尚不清楚。因此，我们通过使用 MTT 试验评估细胞活力、ROS 水平、caspase-3 活性和细胞蛋白质组来研究藤黄果提取物（ME）的这种保护作用。用 5-20μM Aβ((1-42))处理 SK-N-SH 细胞 24 h 会引起形态学上的细胞毒性变化，降低细胞活力并增加 ROS 水平，而在用 Aβ((1-42))诱导之前用 50-400μg/mL ME 预孵育 30 min 可以成功地以剂量依赖的方式预防这种细胞毒性作用（完全在 400μg/mL 时）。400μg/mL ME 还可以预防 Aβ诱导的 caspase-3 活性增加。使用 2-D 凝胶电泳（每组 n = 5 凝胶）和质谱进行蛋白质组分析显示，63 种蛋白质的水平因 Aβ((1-42))诱导而显著改变。有趣的是，通过 ME 预处理可以成功预防 10 种蛋白质的变化。总之，我们在此报告 ME 对 SK-N-SH 细胞中 Aβ诱导的细胞毒性、ROS 增加和 caspase 活性增加的显著保护作用。此外，蛋白质组分析显示，ME 的一些保护作用可能与某些蛋白质有关。对这些蛋白质的进一步特征分析可能会导致确定用于成功预防和/或降低 AD 严重程度的新的治疗靶点。
