岩藻黄质保护视网膜神经节细胞并促进 parkin 介导的线粒体自噬以抵抗谷氨酸兴奋性毒性。

Fucoxanthin protects retinal ganglion cells and promotes parkin-mediated mitophagy against glutamate excitotoxicity.

机构信息

Department of Ophthalmology, The Affiliated People's Hospital of Ningbo University.

Health Science Center, The Ningbo University.

出版信息

Neuroreport. 2023 May 3;34(7):385-394. doi: 10.1097/WNR.0000000000001902. Epub 2023 Apr 1.

DOI:10.1097/WNR.0000000000001902

PMID:37096783

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10097491/

Abstract

OBJECTIVE

To clarify whether fucoxanthin plays a protective role and regulates parkin-mediated mitophagy on retinal ganglion cells (RGCs) against glutamate excitotoxicity.

METHODS

The excitotoxicity model of primary RGCs was carried out with glutamate. Mitochondrial membrane potential was measured by JC-1 kit (Abcam, USA). The apoptotic rate and cytotoxicity were detected by Hoechst staining and lactate dehydrogenase (LDH) kit (Takara, Japan). Mitochondria was assessed by MitoTracker staining and confocal microscopy. The mRNA levels and protein expression levels of Bax, Bcl-2, parkin, optineurin, LC3, and LAMP1 in RGCs were analyzed by quantitative PCR and immunoblotting. Finally, the mitochondrial health score and mitophagy were assessed by transmission electron microscopy.

RESULTS

Fucoxanthin increased the mitochondrial membrane potential of RGCs, reduced cytotoxicity, and decreased apoptosis in RGCs under glutamate excitotoxicity. It also enhanced expression levels of parkin, optineurin, and LAMP1, and upgraded the ratio of LC3-II to LC3-I. Meanwhile, fucoxanthin increased LC3 and MitoTracker co-localization staining. In addition, up-regulated mitochondrial health score, and the number of autophagosomes and mitophagosomes were observed in fucoxanthin-treated RGCs under glutamate excitotoxicity.

CONCLUSION

Fucoxanthin may exert its neuroprotective effect on RGCs via promoting parkin-mediated mitophagy under glutamate excitotoxicity. The neuroprotective effect of fucoxanthin in glaucomatous neurodegeneration and ocular diseases characterized by impaired mitophagy warrants further investigation.

摘要

目的

阐明岩藻黄质是否对谷氨酸兴奋性毒性发挥保护作用，并调节 parkin 介导的对视网膜神经节细胞（RGCs）的线粒体自噬。

方法

用谷氨酸建立 RGCs 的兴奋性毒性模型。用 JC-1 试剂盒（Abcam，美国）测量线粒体膜电位。通过 Hoechst 染色和乳酸脱氢酶（LDH）试剂盒（Takara，日本）检测细胞凋亡率和细胞毒性。通过 MitoTracker 染色和共聚焦显微镜评估线粒体。通过 qPCR 和免疫印迹分析 RGCs 中 Bax、Bcl-2、parkin、optineurin、LC3 和 LAMP1 的 mRNA 水平和蛋白表达水平。最后，通过透射电子显微镜评估线粒体健康评分和自噬。

结果

岩藻黄质增加了谷氨酸兴奋性毒性下 RGCs 的线粒体膜电位，降低了 RGCs 的细胞毒性和凋亡。它还增强了 parkin、optineurin 和 LAMP1 的表达水平，并提高了 LC3-II/LC3-I 的比值。同时，岩藻黄质增加了 LC3 和 MitoTracker 的共定位染色。此外，在谷氨酸兴奋性毒性下，岩藻黄质处理的 RGCs 中观察到上调的线粒体健康评分，以及自噬体和噬线粒体体的数量增加。