Decreased Bacterial Diversity Characterizes the Altered Gut Microbiota in Patients With Psoriatic Arthritis, Resembling Dysbiosis in Inflammatory Bowel Disease

Abstract

Objective To characterize the diversity and taxonomic relative abundance of the gut microbiota in patients with never-treated, recent-onset psoriatic arthritis (PsA). Methods High-throughput 16S rRNA pyrosequencing was utilized to compare community composition of gut microbiota in PsA patients (n=16), subjects with psoriasis of the skin (Ps) (n=15) and healthy, matched-controls (n=17). Samples were further assessed for the presence and levels of fecal and serum secretory immunoglobulin A (sIgA), pro-inflammatory proteins and fatty-acids. Results The gut microbiota observed in PsA and Ps patients was less diverse when compared to healthy controls. These could be attributed to the reduced presence of several taxa. While both groups showed a relative decrease in Coprococcus spp., PsA samples were characterized by a significant reduction in Akkermansia, Ruminococcus, and Pseudobutyrivibrio. Supernatants of fecal samples from PsA patients revealed an increase in sIgA and a decrease in receptor activator of nuclear factor kappa-B ligand (RANKL) levels. Fatty acid analysis revealed low levels of hexanoate and heptanoate in PsA and Ps patients. Conclusion PsA and Ps patients had a lower relative abundance of multiple intestinal bacteria. Although some genera were concomitantly decreased in both conditions, PsA samples had lower abundance of reportedly beneficial taxa. This gut microbiota profile in PsA was similar to that published for patients with IBD and was associated with changes in specific inflammatory proteins unique to this group, and distinct from Ps and controls. Thus, the role of gut microbiota in the continuum of Ps-PsA pathogenesis and the associated immune response merits further study.

The role of the gastrointestinal tract in the pathogenesis of rheumatic diseases

“…Analysis of fatty acids revealed low fecal quantities of hexanoate and heptanoate in both patients with PsA and patients with psoriasis. A similar gut microbiota profile was present in patients with inflammatory bowel disease [43]. In children with enthesitis-related arthritis (ERA) a different microbiome signature has been observed characterized by (i) less Faecalibacterium prausnitzii and lachnospiraceae family, (ii) a statistically significant increase in Bifidobacterium, and (iii) an abundance of Akkermansia muciniphila [44].…”

“…This finding was further supported by the low frequency of Dialister observed in non-inflamed SpA samples and healthy controls. A recent study evaluated the community composition of gut microbiota in patients with PsA, patients with isolated psoriasis of the skin, and healthy control subjects [43]. Samples were further assessed for the presence and levels of fecal and serum secretory IgA (sIgA), proinflammatory proteins, and fatty acids.…”

GUT-the Trojan Horse in Remote Organs’ Autoimmunity

“…Analysis of their fatty acids revealed low fecal quantities of hexanoate and heptanoate, attesting for a different luminal metabolome [90]. Once again, like in comparable gut axes, Th17 has a crucial function in the mechanism [91].…”

“…Hypochloredia, intestinal bacterial over growth, increased intestinal permeability, increased intestinal transit time, expansion of intestinal Bacteroides spp and beneficial probiotic therapy, amelioration on omega-3 fatty acids intake, were described in acne [88,90].…”

SPARTAN annual meeting, New York City 2014

“…A comprehensive review on the potential role of genetic, immunologic, cytokine, and growth factors that may be useful to diagnose, assess disease activity, and progression follows. It should be of great interest to expand the study of the potential contribution of microbes and the microbiota in the pathogenesis of spondyloarthritis and elucidate their role in diagnosis, prevention, and therapy [1,2].…”