Hydrogen peroxide production by lactobacilli promotes epithelial restitution during colitis

Abstract

Inflammatory bowel disease (IBD) is a multifactorial chronic inflammatory disease of the gastrointestinal tract, characterized by cycles of acute flares, recovery and remission phases. Treatments for accelerating tissue restitution and prolonging remission are scarce, but altering the microbiota composition to promote intestinal homeostasis is considered a safe, economic and promising approach. Although probiotic bacteria have not yet fulfilled fully their promise in clinical trials, understanding the mechanism of how they exert beneficial effects will permit devising improved therapeutic strategies. Here we probe if one of the defining features of lactobacilli, the ability to generate nanomolar H2O2, contributes to their beneficial role in colitis. H2O2 generation by wild type L. johnsonii was modified by either deleting or overexpressing the enzymatic H2O2 source(s) followed by orally administering the bacteria before and during DSS colitis. Boosting luminal H2O2 concentrations within a physiological range accelerated recovery from colitis, while significantly exceeding this H2O2 level triggered bacteraemia. This study supports a role for increasing H2O2 within the physiological range at the epithelial barrier, independently of the enzymatic source and/or delivery mechanism, for inducing recovery and remission in IBD.

Proteomic analysis of microbial induced redox-dependent intestinal signaling

“…Similar Nox-1 mediated results were observed for Lactobacillus plantarum in drosophila [18] , suggesting that these increases in ROS leads to oxidation of key cysteine residues that modify protein confirmation and cellular function as depicted in Fig. 1 A. Additionally, a recent report has shown that certain strains of lactobacilli generate hydrogen peroxide [37] , indicating that some cellular protein oxidation is caused by ROS produced by the luminal bacteria themselves. We tested the supernatants from overnight cultures of several strains of lactobacilli, including two of our separate lab stocks of LGG (ATCC 53103), and found that while strains of Lactobacillus acidophilus or Lactobacillus gasseri produced high levels of hydrogen peroxide, in comparison LGG by itself did not produce high levels of hydrogen peroxide relative to the untreated control ( Fig.…”

“…Several lactobacilli strains, which are naturally occurring members of the microbiota and commonly used probiotics, have been shown to generate and/or induce reactive oxygen species (ROS) production [24] , [36] , [37] . We reported that certain strains of lactobacilli, in particular Lactobacillus rhamnosus GG (LGG) can induce rapid, and non-microbicidal generation of ROS within colonic epithelial cells [20] .…”

“…We reported that certain strains of lactobacilli, in particular Lactobacillus rhamnosus GG (LGG) can induce rapid, and non-microbicidal generation of ROS within colonic epithelial cells [20] . This evolutionarily conserved generation of ROS mediates cell signaling responses in mammalian cultured cells, in invertebrate models, and in the murine model [17] , [18] , [22] , [24] , [25] , [3] , [36] , [37] , [39] , [41] , [42] . ROS were initially described as functioning in the bactericidal responses of neutrophils, where high levels of ROS are generated by the catalytic activity of the NADPH oxidase (Nox) enzymes, Nox2/gp120phox, also known as ‘respiratory burst’ [23] .…”

Lactobacillus commensals autochthonous to human milk have the hallmarks of potent probiotics

“…The H 2 O 2 produced by NPL-99 was not effective against S. aureus , but could be a therapeutic strategy in correcting irritable bowel disease (IBD)-associated dysbiosis by augmenting gut barrier integrity [77]. Moderate barrier strengthening as seen in NPL-99 through TEER measurements [78] supports the notion of a probiotic role for treating leaky gut [79].…”

Role of the microbiota in ileitis of a mouse model of inflammatory bowel disease—Glutathione peroxide isoenzymes 1 and 2‐double knockout mice on a C57BL background

“…as probiotics in the treatment of inflammatory bowel disease (IBD) (Guandalini & Sansotta, 2019). Stimulation of crypt/gland localized NOX1 oxidant generation may be beneficial by sustaining proliferation and restitution (Alam et al, 2014; Coant et al, 2010; Jones et al, 2013; Kato et al, 2016; Singh, Hertzberger, & Knaus, 2018). Intestinal DUOX2 activation is downstream of NOD2 detection of cytosolic muramyl dipeptide, a component of bacteria cell walls (Lipinski et al, 2009).…”