外泌体在年龄相关性黄斑变性发病机制中的作用研究进展

外泌体是细胞分泌的纳米级膜性小泡,分布于多种体液,包括外周血、尿液、唾液等.目前多步差速离心是较为有效的外泌体提取方法.外泌体来源多样,可来自各种类型细胞,携带其来源细胞的蛋白质及核酸,参与细胞间的信息交流,在免疫调节、炎症反应等许多病理生理过程中发挥重要功能.年龄相关性黄斑变性(AMD)是引起50岁以上人群严重视力障碍的主要疾病,其发病机制尚不明确,目前认为AMD的发生与多种因素相关.最新研究表明,视网膜色素上皮(RPE)细胞分泌的外泌体可能与AMD的发生有关,RPE细胞通过外泌体释放的αB晶体蛋白等相关蛋白的增加可能导致玻璃膜疣的形成,氧化应激下的外泌体蛋白参与了RPE细胞的凋亡和存活.外泌体中的补体调节因子CD46、CD59通过损伤外层视网膜及Bruch膜参与AMD病程的进展.此外,RPE细胞的外泌体可能与脉络膜血管生成有关.随着对外泌体的深入研究,未来可能为AMD的诊治提供新的途径.

Effects of exosomes in pathogenesis of age-related macular degeneration

Exosomes are nanometer membranous vesicles which can be distributed in a variety of biological fluids,including peripheral blood,urine,saliva and so on.Currently,the multi-step differential centrifugation is a efficient method which can be used to isolate exosomes.Exosomes are released by all types of cells.Exosomes can carry proteins and RNAs from derived cells,involve in exchange of information between cells,and play an important role in physiological and pathological processes of immunoregulation and inflammatory responses.Age-related macular degeneration (AMD) is the leading indication of severe visual impairment in adults over 50 years old.The exact etiology of AMD is still unknown,and its pathogenesis may involve various factors.New studies showed that exosomes secreted by retinal pigment epithelium (RPE) cells may be associated with AMD.The elevated levels of protein in exosomes from RPE,such as αB-crystalline,are associated with druse in AMD.Stress-altered exosomes proteins were found involving in regulation of apoptosis and survival of RPE.RPE cells membrane complement regulators,CD46 and CD59,could contribute to lesion formation in the outer retina and Bruch's membrane during the development of AMD.Further,exosomes from RPE cells may be associated with the genesis of choroidal angiogenesis.There remain thorough studies to be conducted,which would reveal new approaches for the diagnosis and treatment of AMD in the future.