The role of microbiome in rheumatoid arthritis treatment

Abstract

Rheumatoid arthritis (RA) is an autoimmune disorder with multifactorial etiology; both genetic and environmental factors are known to be involved in pathogenesis. Treatment with disease-modifying antirheumatic drugs (DMARDs) plays an essential role in controlling disease progression and symptoms. DMARDs have immunomodulatory properties and suppress immune response by interfering in various pro-inflammatory pathways. Recent evidence has shown that the gut microbiota directly and indirectly modulates the host immune system. RA has been associated with dysbiosis of the gut microbiota. Patients with RA treated with DMARDs show partial restoration of eubiotic gut microbiome. Hence, it is essential to understand the impact of DMARDs on the microbial composition and its consequent influences on the host immune system to identify novel therapies for RA. In this review, we discuss the importance of antirheumatic-drug-induced host microbiota modulations and possible probiotics that can generate eubiosis.

Keywords: disease-modifying antirheumatic drugs; gut microbiota; immune modulation; microbial modulation; probiotics; rheumatoid arthritis.

Figure 1.

Disease-modifying drugs partially normalize the gut microbiomes of responders. The pivotal contribution of gut microbiome in rheumatoid arthritis has been evidenced. Dynamic changes in gut microbiota during a lifetime determine host immunity. Expansion of certain clades of opportunistic commensals likely drives alterations in host’s microbial diversity, metabolic profile, and immune activation before and postdisease onset. Certain drugs like sulfasalazine require gut microbes for activity. Thus, distinct microbial profiles may determine the treatment with disease-modifying antirheumatic drugs (DMARDs). Responders to DMARDs show a partial normalization of the gut microbiota suggesting a crucial role of microbiota in treatment efficacy.