Supplemental Leuconostoc mesenteroides strain NTM048 attenuates imiquimod-induced psoriasis in mice.

AIMS: Psoriasis, a chronic inflammatory skin disease, is associated with altered intestinal microbiota. Here, we investigated the ameliorative effect of Leuconostoc mesenteroides NTM048 strain in imiquimod (IMQ)-induced psoriasis in mice. METHODS AND RESULTS: Mice were administered NTM048 for 21 days alongside the topical application of IMQ on the dorsal skin for 6 consecutive days. IMQ induced psoriatic symptoms such as erythema and scaling and also upregulated interleukin (IL)-17, a key effector cytokine of psoriasis, in the skin. Supplemental NTM048 suppressed these abnormalities, increased the levels of plasma deoxycholic acid (DCA), a secondary bile acid and altered the faecal microbiota composition, as indicated by the increased abundance of Akkermansia and decreased abundance of Staphylococcus and Streptococcus. Notably, DCA treatment of murine splenocytes reduced IL-17 production. CONCLUSIONS: The NTM048-mediated reduction of psoriasis was shown to involve the downregulation of IL-17 in mouse skin, which was possibly associated with the plasma DCA derived from intestinal microbiota. SIGNIFICANCE AND IMPACT OF THE STUDY: Our findings propose not only a novel approach for psoriasis reduction but also a crosstalk between the skin and intestine in psoriasis.

A thermostable collagenolytic protease with a very large molecular mass produced by thermophilic Bacillus sp. strain MO-1.

A collagenolytic protease was purified to homogeneity from thermophilic Bacillus sp. strain MO-1. The protease from strain MO-1 showed high activity toward type I and IV collagens and gelatin. However, peptide substrates (4-phenylazobenzyloxycarbonyl-Pro-Leu-Gly-Pro-Arg and 2-furylacryloyl-Leu-Gly-Pro-Ala) for collagenases were inert as substrates. The collagenolytic protease cleaved oxidized insulin B-chain at 11 sites and degraded type I and IV collagens into anonymous small pieces, suggesting that the protease digests collagens at multiple sites. The collagenolytic protease was far more thermostable than a mesophilic Clostridium histolyticum collagenase. The collagenolytic protease possesses two salient features: (1) it has a very large molecular mass, 210 kDa, and consists of two, identical 105-kDa subunits; (2) it belongs to a serine protease group. The high molecular mass is unique among serine proteases but common for collagenases. The features of the enzyme from strain MO-1 suggest that it is a new collagenolytic protease which is distinct from previously reported collagenases and serine proteases.