Modulation of intestinal epithelial cell proliferation and apoptosis by Lactobacillus gasseri SF1183

Abstract

The gut microbiota exerts a variety of positive effects on the intestinal homeostasis, including the production of beneficial molecules, control of the epithelial barrier integrity and the regulation of the balance between host’s cell death and proliferation. The interactions between commensal bacteria and intestinal cells are still under-investigated and is then of paramount importance to address such interactions at the molecular and cellular levels. We report an in vitro analysis of the effects of molecules secreted by Lactobacillus gasseri SF1183 on HCT116 cells, selected as a model of intestinal epithelial cells. SF1183 is a L. gasseri strain isolated from an ileal biopsy of a human healthy volunteer, able to prevent colitis symptoms in vivo. Expanding previous findings, we show that bioactive molecules secreted by SF1183 reduce the proliferation of HCT116 cells in a reversible manner determining a variation in cell cycle markers (p21WAF, p53, cyclin D1) and resulting in the protection of HCT116 cells from TNF-alfa induced apoptosis, an effect potentially relevant for the protection of the epithelial barrier integrity and reconstitution of tissue homeostasis. Consistently, SF1183 secreted molecules increase the recruitment of occludin, a major component of TJ, at the cell–cell contacts, suggesting a reinforcement of the barrier function.

Probiotics as an Alternative to Antibiotics: Genomic and Physiological Characterization of Aerobic Spore Formers from the Human Intestine

“…At 80% confluence, cells were harvested and diluted in 6-well plates to a total concentration of 5.5 × 10 6 cells per well. Bacterial conditioned medium (CM), required for the treatment of the HT-29 cells, was obtained by growing bacterial cells in minimal S7 medium, aerobically, for 16 h at 37 °C [ 44 ]. The culture was then centrifuged (7000 rpm for 10 min) and the supernatant (CM) was filtered through a 0.22 µm low protein binding filter (Millex, Millipore, Bedford, MA, USA).…”

“…The culture was then centrifuged (7000 rpm for 10 min) and the supernatant (CM) was filtered through a 0.22 µm low protein binding filter (Millex, Millipore, Bedford, MA, USA). The obtained CM was used for HT-29 cells treatment at a concentration of 20% v / v in a complete growth medium as previously reported [ 44 ]. After 24 h incubation of HT-29 cells with 20% CM, the cells were harvested, lysed, and cell extracts were prepared for Western blot analysis as described below.…”

Genetic and dietary determinants of gut microbiome-bile acid interactions in the BXD recombinant inbred mouse population

“…3B), with the most correlated genus being Lactobacillus (CCA coe cient: -0.67). Lactobacillus has been shown to modulate cell growth 42 , and indeed, C1_CD was related to genes involved in cell proliferation and cellular stress, notably MYC targets v1 43 , oxidative phosphorylation (OXPHOS) 44 , and heat shock factor 1 45 (HSF1) targets (Fig. 3D).…”

Exopolysaccharide production by Lactobacillus plantarum T10 is responsible for the probiotic activity in enhancing intestinal barrier function in vitro and in vivo

“…Previous reports have also highlighted the ability of lactobacilli to alleviate stress-induced apoptosis. [37][38][39] Notably, some studies have demonstrated that the production of EPS by Lactobacillus strains plays a critical role in reducing apoptosis. 38,40 We hypothesize that L. plantarum T10 may protect against intestinal apoptosis through EPS based on these findings.…”