Pubblicazioni AAT

Lactobacillus crispatus M247-derived H2O2 acts as a signal transducing molecule activating peroxisom

Data: 06/10/2009

Sandra Voltan, Diego Martines, Marina Elli, Paola Brun, Stefano Longo, Andrea Porzionato, Raffaele DeCaro, Giorgio Palù, Giacomo C. Sturniolo, Lorenzo Morelli, Ignazio Castagliuolo (2008) Gastroenterology 135(4):1216-27.

BACKGROUND & AIMS: Accumulating evidence indicates that the peroxisome proliferator activated receptor (PPAR)-gamma is a major player in maintaining intestinal mucosa homeostasis, but whether PPAR-gamma is directly involved in probiotic-mediated effects and the molecular events involved in its activation are not known. METHODS: We investigated the role of PPAR-gamma in the immunomodulatory effects of Lactobacillus crispatus M247 on intestinal epithelial cells (IEC) and the role of probiotic-derived H(2)O(2) on PPAR-gamma activity. RESULTS: L crispatus M247 supplementation in mice significantly increased PPAR-gamma levels and transcriptional activity in the colonic mucosa. L crispatus M247 induced PPAR-gamma nuclear translocation and enhanced transcriptional activity in epithelial (CMT-93) cells, as demonstrated by the increased luciferase activity of a PPAR-gamma-responsive element, PPAR-gamma-responsive gene up-regulation, and reduced activity of an nuclear factor-kappaB-responsive element. Pharmacologic PPAR-gamma inhibition or silencing by small interfering RNA cancelled the L crispatus M247-mediated effects in CMT-93 cells. Because Lactobacillus strains producing little H(2)O(2) failed to activate PPAR-gamma, we investigated the role of L crispatus M247-derived H(2)O(2) in PPAR-gamma activation. L crispatus M247 induced a transient rise in intracellular H(2)O(2) and PPAR-gamma transcriptional activity was cancelled by antioxidant or H(2)O(2) scavenger. Toll-like receptor (TLR)-2 was not required for PPAR-gamma up-regulation mediated by L crispatus M247 in mice, although the protective effects of L crispatus M247 on dextran sodium sulfate-induced colitis were less pronounced in TLR-2(-/-) mice. CONCLUSIONS: L crispatus M247 uses H(2)O(2) as a signal transducing molecule to induce PPAR-gamma activation in IEC, directly modulating epithelial cell responsiveness to inflammatory stimuli.

Beneficial effect of auto-aggregating Lactobacillus crispatus on experimentally induced colitis

Data: 04/01/2010

Aggregating phenotype in Lactobacillus crispatus determines intestinal colonization and TLR2 and TLR

Data: 04/01/2010

Proteomic investigation of the aggregation phenomenon in Lactobacillus crispatus

Data: 04/01/2010

Assessment of susceptibility towards biocides within lactic acid bacteria

Data: 30/01/2013

Biocide susceptibility within bifidobacteria of animal and human origin

Data: 30/01/2013

Assessment of susceptibility of moulds isolates towards biocides

Kalkanci A, Elli M, Adil Fouad A, Yesilyurt E, Jabban Khalil I. Assessment of susceptibility of moulds isolates towards biocides. J Mycol Med. 2015 Dec;25(4):280-6. doi: 10.1016/j.mycmed.2015.08.001. Epub 2015 Sep 26.