Emerging role of gut microbiota in autoimmune diseases

Abstract

Accumulating studies have indicated that the gut microbiota plays a pivotal role in the onset of autoimmune diseases by engaging in complex interactions with the host. This review aims to provide a comprehensive overview of the existing literatures concerning the relationship between the gut microbiota and autoimmune diseases, shedding light on the complex interplay between the gut microbiota, the host and the immune system. Furthermore, we aim to summarize the impacts and potential mechanisms that underlie the interactions between the gut microbiota and the host in autoimmune diseases, primarily focusing on systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, type 1 diabetes mellitus, ulcerative colitis and psoriasis. The present review will emphasize the clinical significance and potential applications of interventions based on the gut microbiota as innovative adjunctive therapies for autoimmune diseases.

Keywords: autoimmune disease; gut microbiota; homeostasis; microbiome; probiotics.

Figure 1

Role of the gut microbiota in autoimmune disease. The gut microbiota contributes to the pathogenesis of autoimmune diseases through various complicated mechanisms, such as the secretion of SCFAs, modulation of NF-κB and Nrf2 signaling pathways, disruption of the balance between Treg, Th1, and Th17 cells, and modulation the release of inflammatory factors. The image was created utilizing the FigDraw online platform (https://www.figdraw.com/#/) and was identified by the in-house image ID: UPORSc4cf4. SCFAs: Short chain fatty acids; MUC2: Recombinant Mucin 2; ROS: Reactive oxygen species; GPR109a: G protein-coupled receptor 109a; FFAR2/3: Recombinant Free Fatty Acid Receptor 2/3; NF-κB: Nuclear factor kappa-B; COX-2: Cyclooxygenase 2; iNOS: Inducible nitric oxide synthase; ZO-1: Zona Occludens 1; MAPK: Mitogen-activated protein kinase; IL-1β: Interleukin-1 beta; TNF-α: Tumor necrosis factor alpha; Est-1: Estrogen sulfotransferase-1; SHP-2: SH2 domain-containing protein-tyrosine phosphatase-2; Nrf-2: NF-E2-related factor 2; HO-1: Recombinant Heme Oxygenase 1; IL-6: Interleukin-6; IL-10: Interleukin-10; TGF-β: Transforming growth factor beta; IFN-γ: Interferon gamma; IL-17: Interleukin-17; IL-21/IL-22: Interleukin-21/Interleukin-22; IL-12 p40: Interleukin-12 p40.