Abstract:
The first discovered vitamin, vitamin A, exists in a range of forms, primarily retinoids and provitamin carotenoids. The bioactive forms of vitamin A, retinol and retinoic acid, have many critical functions in body systems including the eye and immune system. Vitamin A deficiency is associated with dysfunctional immunity, and presents clinically as a characteristic ocular syndrome, xerophthalmia. The immune functions of vitamin A extend to the gut, where microbiome interactions and nutritional retinoids and carotenoids contribute to the balance of T cell differentiation, thereby determining immune status and contributing to inflammatory disease around the whole body. In the eye, degenerative conditions affecting the retina and uvea are influenced by vitamin A. Stargardt\'s disease (STGD1; MIM 248200) is characterised by bisretinoid deposits such as lipofuscin, produced by retinal photoreceptors as they use and recycle a vitamin A-derived chromophore. Age-related macular degeneration features comparable retinal deposits, such as drusen featuring lipofuscin accumulation; and is characterised by parainflammatory processes. We hypothesise that local parainflammatory processes secondary to lipofuscin deposition in the retina are mediated by T cells interacting with dietary vitamin A derivatives and the gut microbiome, and outline the current evidence for this. No cures exist for Stargardt\'s or age-related macular degeneration, but many vitamin A-based therapeutic approaches have been or are being trialled. The relationship between vitamin A\'s functions in systemic immunology and the eye could be further exploited, and further research may seek to leverage the interactions of the gut-eye immunological axis.
摘要:
最早发现的维生素,维生素A,以各种形式存在,主要是类维生素A和维生素原类胡萝卜素。维生素A的生物活性形式,视黄醇和视黄酸,在身体系统中具有许多关键功能,包括眼睛和免疫系统。维生素A缺乏与免疫功能失调有关,并在临床上表现为一种特征性的眼部综合征,干眼症.维生素A的免疫功能延伸到肠道,其中微生物组相互作用和营养类维生素A和类胡萝卜素有助于T细胞分化的平衡,从而确定免疫状态并导致整个身体周围的炎症性疾病。在眼睛里,影响视网膜和葡萄膜的退行性疾病受维生素A的影响。Stargardt病(STGD1;MIM248200)的特征是双维甲酸沉积物,如脂褐素,由视网膜光感受器在使用和回收维生素A衍生的发色团时产生。年龄相关性黄斑变性的特征相当的视网膜沉积,例如以脂褐素积累为特征的玻璃疣;并以副炎症过程为特征。我们假设视网膜中脂褐素沉积后的局部副炎症过程是由T细胞与膳食维生素A衍生物和肠道微生物组相互作用介导的。并概述目前的证据。没有治疗Stargardt或年龄相关性黄斑变性的方法,但是许多基于维生素A的治疗方法已经或正在试验。维生素A在全身免疫学中的功能与眼睛之间的关系可以进一步利用,进一步的研究可能会寻求利用肠眼免疫轴的相互作用。