Li Lin, Hu Guo-ku
*Department of Bioengineering, College of Materials and Chemistry Chemical Engineering, Chengdu University of Technology, Chengdu, 610059, China.
Biosci Rep. 2015 Feb 25;35(1):e00174. doi: 10.1042/BSR20140104.
Apoptosis mediates the precise and programmed natural death of neurons and is a physiologically important process in neurogenesis during maturation of the central nervous system. However, premature apoptosis and/or an aberration in apoptosis regulation are implicated in the pathogenesis of neurodegeneration. Thus, it is important to identify neuronal pathways/factors controlling apoptosis. Pink1 [phosphatase and tensin homologue (PTEN)-induced kinase 1] is a ubiquitously expressed gene and has been reported to have a physiological role in mitochondrial maintenance, suppressing mitochondrial oxidative stress, fission and autophagy. However, how Pink1 is involved in neuronal survival against oxidative stress remains not well understood. In the present paper, we demonstrate that thapsigargin, a specific irreversible inhibitor of endoplasmic reticulum (ER) calcium-ATPase, could lead to dramatic oxidative stress and neuronal apoptosis by ectopic calcium entry. Importantly, the neuronal toxicity of thapsigargin inhibits antioxidant gene Pink1 expression. Although Pink1 knockdown enhances the neuronal apoptosis by thapsigargin, its overexpression restores it. Our findings have established the neuronal protective role of Pink1 against oxidative stress and afford rationale for developing new strategy to the therapy of neurodegenerative diseases.
细胞凋亡介导神经元精确且程序性的自然死亡,是中枢神经系统成熟过程中神经发生的一个重要生理过程。然而,过早的细胞凋亡和/或细胞凋亡调节异常与神经退行性疾病的发病机制有关。因此,识别控制细胞凋亡的神经元途径/因子很重要。Pink1[磷酸酶和张力蛋白同源物(PTEN)诱导激酶1]是一个广泛表达的基因,据报道在维持线粒体、抑制线粒体氧化应激、裂变和自噬方面具有生理作用。然而,Pink1如何参与神经元抵抗氧化应激的存活仍不清楚。在本文中,我们证明了毒胡萝卜素,一种内质网(ER)钙ATP酶的特异性不可逆抑制剂,可通过异位钙内流导致显著的氧化应激和神经元凋亡。重要的是,毒胡萝卜素的神经元毒性会抑制抗氧化基因Pink1的表达。虽然敲低Pink1会增强毒胡萝卜素诱导的神经元凋亡,但过表达Pink1则可恢复神经元凋亡。我们的研究结果确立了Pink1对氧化应激的神经元保护作用,并为开发神经退行性疾病治疗的新策略提供了理论依据。