Is the composition of intestinal microbiota a marker for psoriasis?

According to a new study, psoriasis could be characterized by the depletion of the bacterium Akkermansia muciniphila in the intestinal microbiota. This study opens new avenues of investigation into this skin disorder.

 

Psoriasis is a chronic inflammatory skin disorder, in which specific immunity cells (Th17) likely play a significant part. Since the intestinal microbiota seems to regulate the maturation and activity of these cells, it could be directly involved in the onset of psoriasis, as it is in that of obesity and several intestinal inflammatory diseases. It should be reminded that these disorders share several characteristics with psoriasis, such as the type of immune response and the type of inflammatory molecules produced.

In order to validate this assumption, a team of researchers analyzed the intestinal microbiota of about thirty volunteers, half of which had psoriasis. The main differences observed were centered on two bacteria: Clostridium citroniae, which was much more abundant in psoriatic patients, and Akkermansia muciniphila, which was significantly less abundant. The researchers pointed out that this is also the case in obese patients or with a chronic intestinal disorder.

In a healthy adult, Akkermansia muciniphila is one of the most abundant bacteria in the colon, representing between 3% and 5% of the microbial species in the microbiota. It could be involved in the intestinal barrier function and be an indicator of an individual’s good health. It thus seems that the pathogenesis of psoriasis has another common feature with that of diseases such as obesity or Crohn’s disease, and this could provide a new research focus.

 

Sources:

Tan et al. The Akkermansia-muciniphila is a gut microbiota signature in psoriasis. doi: 10.1111/exd.13463