Department of Experimental Medicine, Sapienza University, Viale Regina Elena 321, 00161 Rome, Italy.
Nutrients. 2020 Oct 28;12(11):3302. doi: 10.3390/nu12113302.
Non-alcoholic fatty liver disease (NAFLD) is the first cause of chronic liver disease worldwide; it ranges from simple steatosis to steatohepatitis (NASH) and, potentially, cirrhosis and hepatocarcinoma. NAFLD is also an independent risk factor for type 2 diabetes, cardiovascular diseases, and mortality. As it is largely associated with insulin resistance and related disorders, NAFLD has been recently re-named as Metabolic dysfunction-Associated Fatty Liver Disease (MAFLD). At present, there are no approved pharmacological treatments for this condition. Vitamin D is a molecule with extensive anti-fibrotic, anti-inflammatory, and insulin-sensitizing properties, which have been proven also in hepatic cells and is involved in immune-metabolic pathways within the gut-adipose tissue-liver axis. Epidemiological data support a relationship hypovitaminosis D and the presence of NAFLD and steatohepatitis (NASH); however, results from vitamin D supplementation trials on liver outcomes are controversial. This narrative review provides an overview of the latest evidence on pathophysiological pathways connecting vitamin D to NAFLD, with emphasis on the effects of vitamin D treatment in MAFLD by a nonsystematic literature review of PubMed published clinical trials. This article conforms to the Scale for Assessment of Narrative Review Articles (SANRA) guidelines. Evidence so far available supports the hypothesis of potential benefits of vitamin D supplementation in selected populations of NAFLD patients, as those with shorter disease duration and mild to moderate liver damage.
非酒精性脂肪性肝病 (NAFLD) 是全球慢性肝病的首要病因；其疾病谱从单纯性脂肪变性发展为脂肪性肝炎 (NASH)，并可能进展为肝硬化和肝癌。NAFLD 也是 2 型糖尿病、心血管疾病和死亡率的独立危险因素。由于其与胰岛素抵抗和相关代谢紊乱密切相关，NAFLD 最近被重新命名为代谢相关脂肪性肝病 (MAFLD)。目前，尚无针对该疾病的获批药物治疗方法。维生素 D 是一种具有广泛抗纤维化、抗炎和胰岛素增敏特性的分子，其在肝细胞中的作用已得到证实，并参与了肠道-脂肪组织-肝脏轴内的免疫代谢途径。流行病学数据支持维生素 D 缺乏与 NAFLD 和脂肪性肝炎 (NASH) 的发生之间存在关联；然而，维生素 D 补充试验对肝脏结局的研究结果存在争议。本综述概述了将维生素 D 与 NAFLD 联系起来的最新病理生理学途径的证据，并通过对 Pubmed 发表的临床试验进行非系统性文献回顾，重点介绍了维生素 D 治疗 MAFLD 的效果。本文符合叙事性综述评估工具 (SANRA) 指南。迄今为止的证据支持在具有较短疾病病程和轻度至中度肝损伤的 NAFLD 患者中补充维生素 D 可能具有潜在益处的假设。
