BACKGROUND

Recent studies, mostly conducted in Western countries, showed that gut microbes are involved in the pathogenesis of multiple sclerosis (MS).

OBJECTIVE

The aim of this study was to investigate whether gut dysbiosis is relevant to the initiation and progression of MS in a Chinese population.

METHODS

Next-generation sequencing (NGS) and gas chromatography (GC) were integrated and used to compare the fecal bacterial communities and the short-chain fatty acid (SCFA) levels among relapsing-remitting MS (RRMS) patients (n = 34), neuromyelitis optica spectrum disorder (NMOSD) patients (n = 34), and healthy controls (HCs) (n = 34). T-cell profile analyses were performed by flow cytometry for MS patients and matched controls (n = 12).

RESULTS

(1) The gut microbiome of MS patients was characterized by an increase of Streptococcus and a decrease of Prevotella_9; additionally, compared to NMOSD patients, Prevotella_9 was found to be much more abundant in MS patients. (2) A striking depletion of fecal acetate, propionate, and butyrate was observed in MS patients compared to HCs. (3) The abundance of Streptococcus was negatively correlated with the proportion of pTregs (P < 0.05) and positively correlated with Th17 cells (P < 0.05) in the peripheral blood, while the abundance of Prevotella_9 was negatively correlated with the Th17 cell frequency (P < 0.01), and the fecal SCFA level was positively correlated with pTreg frequency (P < 0.05).

CONCLUSIONS

Gut dysbiosis and a lack of SCFAs exist in Chinese MS patients, which might be related to an aberrant immune response of MS; this relationship may have a diagnostic and therapeutic value for patients with MS.