视网膜中小胶质细胞对光感受器细胞的作用

Effect of microglia on photoreceptor in retina

小胶质细胞作为视网膜的固有免疫细胞,能够主动监测周围微环境的变化。光感受器细胞作为视网膜的一级神经元,能够将光信号转换为电信号。在视网膜的多种生理、病理环境中,小胶质细胞对光感受器细胞的功能或存活具有重要影响。在视网膜发育过程中,小胶质细胞吞噬细胞碎片、促进神经发生及突触塑形。在健康视网膜环境中,小胶质细胞能够维持内环境稳定、维持神经元突触结构和功能、分泌营养因子。关于视网膜疾病的研究,既往多关注小胶质细胞的损害作用。随着研究进展发现,在视网膜急性损伤和应激(视网膜脱离、朊病毒损伤、光损伤)中,小胶质细胞对光感受器细胞的保护作用大于损害作用。在视网膜慢性炎性疾病,如视网膜色素变性、年龄相关性黄斑变性、糖尿病视网膜病变中,免疫微环境失衡,小胶质细胞被过度激活,释放大量炎性因子,吞噬非凋亡光感受器细胞,其损害作用大于保护作用。如何发挥小胶质细胞的保护作用而抑制其损害作用,对视网膜疾病,尤其是慢性炎性疾病的治疗具有重要意义。本文就不同视网膜条件下小胶质细胞对光感受器细胞的作用进行综述。

Microglia,the innate immune cells of the retina,can actively monitor changes in the surrounding microenvironment.Photoreceptors,as the primary neurons of the retina,can convert light signals into electrical signals.Microglia play an important role in the function or survival of photoreceptors in various physiological and pathological conditions of the retina.During the development of the retina,microglia phagocytize cell debris and promote neurogenesis and synaptic plasticity.In a healthy retinal environment,microglia can maintain retinal homeostasis,maintain synaptic structure and function of neurons,and secrete neurotrophic factors.In the past,more attention has been paid to the damage of microglia in retinal diseases.In acute retinal injury and stress(retinal detachment,prion-induced damage,light-induced damage),the protective effect of microglial cells on photoreceptors is greater than damage.In retinal chronic inflammatory diseases such as retinitis pigmentosa,age-related macular degeneration and diabetic retinopathy,the immune microenvironment is imbalanced,microglia are overactivated,release a large number of inflammatory factors,phagocytize non-apoptotic photoreceptors,the damage is greater than protective effect.How to utilize the protective effect of microglia and inhibit their damage is of great significance for the treatment of retinal diseases,especially chronic inflammatory diseases.This article reviews the effects of microglia on photoreceptor cells under different retinal conditions.