Abstract: Non-alcoholic fatty liver disease (NAFLD) is one of the most prevalent chronic liver diseases worldwide. Its pathogenesis is closely related to gut microbiota dysbiosis and it is a typical metabolic liver disease. Currently, there are no specific therapeutic drugs, and clinical intervention is still mainly based on lifestyle modifications, with limited efficacy and a high relapse rate. Dysfunction of the gut-liver axis plays a crucial role in the occurrence and progression of NAFLD. Gut microbiota dysbiosis can drive hepatic lipid metabolism disorders and fibrosis by disrupting the intestinal barrier, promoting endotoxin translocation, and inducing systemic low-grade inflammation. This article systematically reviews the structural and functional characteristics of the gut microbiota associated with NAFLD, focusing on the gut-liver axis, a core pathological regulatory axis. It highlights recent progress in understanding how probiotics alleviate NAFLD through multiple mechanisms, including regulating gut microbiota homeostasis, enhancing intestinal barrier function, and regulating short-chain fatty acid and bile acid metabolism. This paper further discusses the applicability and limitations of various microecological intervention strategies, including traditional probiotics, next-generation probiotics, prebiotics, synbiotics, and fecal microbiota transplantation, under different research backgrounds, emphasizing the decisive influence of strain specificity, individual differences, and intervention timing on efficacy. Based on this, this paper points out that current clinical research still lacks significant evidence regarding long-term efficacy verification and precise microecological intervention. Taking into account the development trends of multi-omics technologies and synthetic biology, this article proposes that future efforts should focus on integrating host-microbe interaction network data and constructing individualized efficacy prediction models to promote the transformation of probiotic intervention from empirical application to a precise microecological treatment model with clear mechanisms and hierarchical management, providing a systematic and forward-looking theoretical basis for the prevention and treatment of NAFLD.

Key words: non-alcoholic fatty liver disease; probiotics; gut microbiota; gut-liver axis

摘要： 非酒精性脂肪性肝病（non-alcoholic fatty liver disease，NAFLD）是全球最流行的慢性肝病之一，其发病与肠道菌群失调密切相关，属于一种典型的代谢性肝病，目前缺乏特异性治疗药物，临床干预仍以调整生活方式为主，疗效有限且易复发。“肠-肝轴”功能紊乱在NAFLD的发生与发展中发挥关键作用。肠道菌群失调可通过破坏肠道屏障、促进内毒素易位及诱导全身性低度炎症驱动肝脏脂质代谢紊乱和纤维化进程。本文围绕“肠-肝轴”这一核心病理调控轴，系统梳理NAFLD相关肠道菌群结构与功能特征，重点总结益生菌通过调节菌群稳态、增强肠道屏障功能以及调控短链脂肪酸和胆汁酸代谢等多重机制缓解NAFLD的研究进展。同时进一步论述传统益生菌、下一代益生菌、益生元、合生元及粪菌移植等多种微生态干预策略在不同研究背景下的适用性与局限性，强调菌株特异性、个体差异及干预时机对疗效的决定性影响。在此基础上，本文指出当前临床研究在长期疗效验证及精准微生态干预方面仍存在显著证据不足，并结合多组学技术与合成生物学的发展趋势，提出未来应通过整合宿主-微生物相互作用网络数据、构建个体化疗效预测模型推动益生菌干预由经验性应用向机制明确、分层管理的精准微生态治疗模式转变，为NAFLD防治提供系统性和前瞻性的理论依据。

关键词: 非酒精性脂肪性肝病；益生菌；肠道菌群；肠-肝轴