Department of Anatomy, Faculty of Science, Mahidol University, Bangkok 10400, Thailand.
Chulabhorn International College of Medicine, Thammasat University, Pathumthani 12120, Thailand.
Int J Mol Sci. 2023 May 10;24(10):8528. doi: 10.3390/ijms24108528.
Parkinson's disease (PD) is associated with dopaminergic neuron loss and alpha-synuclein aggregation caused by ROS overproduction, leading to mitochondrial dysfunction and autophagy impairment. Recently, andrographolide (Andro) has been extensively studied for various pharmacological properties, such as anti-diabetic, anti-cancer, anti-inflammatory, and anti-atherosclerosis. However, its potential neuroprotective effects on neurotoxin MPP-induced SH-SY5Y cells, a cellular PD model, remain uninvestigated. In this study, we hypothesized that Andro has neuroprotective effects against MPP-induced apoptosis, which may be mediated through the clearance of dysfunctional mitochondria by mitophagy and ROS by antioxidant activities. Herein, Andro pretreatment could attenuate MPP-induced neuronal cell death that was reflected by reducing mitochondrial membrane potential (MMP) depolarization, alpha-synuclein, and pro-apoptotic proteins expressions. Concomitantly, Andro attenuated MPP-induced oxidative stress through mitophagy, as indicated by increasing colocalization of MitoTracker Red with LC3, upregulations of the PINK1-Parkin pathway, and autophagy-related proteins. On the contrary, Andro-activated autophagy was compromised when pretreated with 3-MA. Furthermore, Andro activated the Nrf2/KEAP1 pathway, leading to increasing genes encoding antioxidant enzymes and activities. This study elucidated that Andro exhibited significant neuroprotective effects against MPP-induced SH-SY5Y cell death in vitro by enhancing mitophagy and clearance of alpha-synuclein through autophagy, as well as increasing antioxidant capacity. Our results provide evidence that Andro could be considered a potential supplement for PD prevention.
帕金森病（PD）与多巴胺能神经元丧失和由 ROS 过度产生引起的α-突触核蛋白聚集有关，导致线粒体功能障碍和自噬受损。最近，穿心莲内酯（Andro）因其各种药理学特性而被广泛研究，例如抗糖尿病、抗癌、抗炎和抗动脉粥样硬化。然而，其对 MPP 诱导的 SH-SY5Y 细胞（一种细胞 PD 模型）的潜在神经保护作用尚未得到研究。在本研究中，我们假设 Andro 对 MPP 诱导的凋亡具有神经保护作用，这可能是通过自噬清除功能失调的线粒体和抗氧化活性清除 ROS 来介导的。在此，Andro 预处理可以减轻 MPP 诱导的神经元细胞死亡，这反映在减少线粒体膜电位（MMP）去极化、α-突触核蛋白和促凋亡蛋白的表达。同时，Andro 通过自噬减轻 MPP 诱导的氧化应激，如 MitoTracker Red 与 LC3 的共定位增加、PINK1-Parkin 通路的上调以及自噬相关蛋白的上调所表明的。相反，当用 3-MA 预处理时，Andro 激活的自噬受到损害。此外，Andro 激活了 Nrf2/KEAP1 通路，导致编码抗氧化酶和活性的基因增加。这项研究阐明了 Andro 通过增强自噬和清除α-突触核蛋白来增强自噬，以及增加抗氧化能力，在体外对 MPP 诱导的 SH-SY5Y 细胞死亡表现出显著的神经保护作用。我们的结果提供了证据表明，Andro 可以被认为是预防 PD 的潜在补充剂。
