Identification of bacterial lipopeptides as key players in irritable bowel syndrome (IBS)

"Objectives Clinical studies revealed that early-life adverse events contribute to the development of IBS in adulthood. The aim of our study was to investigate the relationship between prenatal stress (PS), gut microbiota and visceral hypersensitivity with a focus on bacterial lipopeptides containing γ-aminobutyric acid (GABA).

Design We developed a model of PS in mice and evaluated, in adult offspring, visceral hypersensitivity to colorectal distension (CRD), colon inflammation, barrier function and gut microbiota taxonomy. We quantified the production of lipopeptides containing GABA by mass spectrometry in a specific strain of bacteria decreased in PS, in PS mouse colons, and in faeces of patients with IBS and healthy volunteers (HVs). Finally, we assessed their effect on PS-induced visceral hypersensitivity.

Results Prenatally stressed mice of both sexes presented visceral hypersensitivity, no overt colon inflammation or barrier dysfunction but a gut microbiota dysbiosis. The dysbiosis was distinguished by a decreased abundance of Ligilactobacillus murinus, in both sexes, inversely correlated with visceral hypersensitivity to CRD in mice. An isolate from this bacterial species produced several lipopeptides containing GABA including C14AsnGABA. Interestingly, intracolonic treatment with C14AsnGABA decreased the visceral sensitivity of PS mice to CRD. The concentration of C16LeuGABA, a lipopeptide which inhibited sensory neurons activation, was decreased in faeces of patients with IBS compared with HVs.

Conclusion PS impacts the gut microbiota composition and metabolic function in adulthood. The reduced capacity of the gut microbiota to produce GABA lipopeptides could be one of the mechanisms linking PS and visceral hypersensitivity in adulthood."

Authors

Camille Petitfils, Sarah Maurel, Gaelle Payros, Amandine Hueber, Bahija Agaiz, Géraldine Gazzo, Rémi Marrocco, Frédéric Auvray, Geoffrey Langevin, Jean-Paul Motta, Pauline Floch, Marie Tremblay-Franco, Jean-Marie Galano, Alexandre Guy, Thierry Durand, Simon Lachambre, Anaëlle Durbec, Hind Hussein, Lisse Decraecker, Justine Bertrand-Michel, Abdelhadi Saoudi, Eric Oswald, Pierrick Poisbeau, Gilles Dietrich, Chloe Melchior, Guy Boeckxstaens, Matteo Serino, Pauline Le Faouder, Nicolas Cenac

See the publication