Diet as a Modulator of Intestinal Microbiota in Rheumatoid Arthritis

Abstract

Rheumatoid arthritis (RA) is a chronic immune-driven inflammatory disease characterised by synovial inflammation, leading to progressive cartilage and bone destruction, impacting patients’ functional capacity and quality of life. Patients with RA have significant differences in gut microbiota composition when compared to controls. Intestinal dysbiosis influences the intestinal barrier strength, integrity and function, and diet is considered the main environmental factor impacting gut microbiota. Over the last few years, researchers have focused on the influence of single components of the diet in the modulation of intestinal microbiota in RA rather than whole dietary patterns. In this review, we focus on how the Mediterranean diet (MD), a whole dietary pattern, could possibly act as an adjuvant therapeutic approach, modulating intestinal microbiota and intestinal barrier function in order to improve RA-related outcomes. We also review the potential effects of particular components of the MD, such as n-3 polyunsaturated fatty acids (PUFAs), polyphenols and fibre.

Impact of Mediterranean Diet on Disease Activity and Gut Microbiota Composition of Rheumatoid Arthritis Patients

“…It has also been suggested that the gut microbiota can be significantly modulated by different environmental factors such as diet, smoke, and therapy [ 1 , 10 ]. On the other hand, it has been reported, with contrasting results, that diet regimen can influence arthritis onset and outcome [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ]. Unlike the western diet, the Mediterranean diet is composed of a variety of foods and has been reported as the best-balanced and complete diet that provides antioxidant, anti-inflammatory, and prebiotic effects [ 12 , 13 ].…”

“…Foods rich in fibers, such as those present in the Mediterranean diet, indeed, are degraded by Firmicutes and Bacteroidetes into short-chain fatty acids (SCFA), such as butyrate, [ 17 , 18 ], which can result in a protective effect on the intestinal barrier by reducing its permeability [ 19 ]. A number of studies have also suggested associations between dietary habits, and RA development and outcome; however, the results are still scarce and contrasting [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ]. In this study, we found a protective role of the Mediterranean diet on the disease activity of RA patients supported by a healthy impact on microbiota composition.…”

Omega-3 Polyunsaturated Fatty Acids and the Intestinal Epithelium—A Review

“…Djuric et al have recently described that ω-3 PUFA consumption induced small changes to gut microbial populations in humans, which were associated with increased colonic EPA to arachidonic acid ratios and a reduction in colonic PGE 2 expression [ 76 ]. Associations between increased favourable gut microbial populations and improved disease outcomes with ω-3 PUFA treatment have also been reported in obesity [ 77 ], rheumatoid arthritis [ 78 ] and cancer [ 79 ]. The microbial populations that appear to be promoted by increased ω-3 PUFA intake, including Bacteroidetes , Firmicutes , Lachnospiraceae , Bifidobacteria , and Enterobacteria , exhibit anti-inflammatory properties through increased production of SCFAs, particularly butyrate, and reduced endotoxaemia [ 80 ].…”

Gut Microbiota Interaction with the Central Nervous System throughout Life

“…Moreover, pro and prebiotics have emerged as a prominent alternative for the dietary industry to relieve aging-associated diseases [ 197 , 198 ]. Diet has been proposed as a modulator of gut microbiota in different conditions, such as rheumatoid arthritis, osteoarthritis, epilepsy, Parkinson’s disease (PD), and Alzheimer’s diasease (AD), among others [ 199 , 200 , 201 , 202 , 203 ]. Interestingly, in elderly subjects defined as community dwellers, a direct correlation was found between gut microbiota diversity and a diet rich in fibre and low in fat compared with elderly subjects that live long-term in residential care [ 169 ].…”