Abstract：
Vitamin A is an essential fat-soluble vitamin that occurs in various chemical forms. It is essential for several physiological processes. Either hyper- or hypovitaminosis can be harmful. One of the most important vitamin A functions is its involvement in visual phototransduction, where it serves as the crucial part of photopigment, the first molecule in the process of transforming photons of light into electrical signals. In this process, large quantities of vitamin A in the form of 11-cis-retinal are being isomerized to all-trans-retinal and then quickly recycled back to 11-cis-retinal. Complex machinery of transporters and enzymes is involved in this process (i.e., the visual cycle). Any fault in the machinery may not only reduce the efficiency of visual detection but also cause the accumulation of toxic chemicals in the retina. This review provides a comprehensive overview of diseases that are directly or indirectly connected with vitamin A pathways in the retina. It includes the pathophysiological background and clinical presentation of each disease and summarizes the already existing therapeutic and prospective interventions.
摘要：
维生素A是一种必需的脂溶性维生素，以各种化学形式存在。它对几个生理过程至关重要。维生素缺乏症或维生素缺乏症都可能是有害的。维生素A最重要的功能之一是它参与视觉光转导，它是感光颜料的关键部分，将光子转换为电信号的过程中的第一个分子。在这个过程中,大量的维生素A以11-顺式-视黄醛的形式被异构化为全反式-视黄醛，然后迅速循环回11-顺式-视黄醛。转运蛋白和酶的复杂机制参与了这一过程(即，视觉周期)。机械中的任何故障不仅会降低视觉检测的效率，还会导致视网膜中有毒化学物质的积累。这篇综述提供了与视网膜中维生素A途径直接或间接相关的疾病的全面概述。它包括每种疾病的病理生理背景和临床表现，并总结了已经存在的治疗和前瞻性干预措施。
