The protective role of Lactobacillus rhamnosus GG postbiotic on the alteration of autophagy and inflammation pathways induced by gliadin in intestinal models

Francesca Furone; Claudia Bellomo; Martina Carpinelli; Martina Nicoletti; Francesca Natasha Hewa-Munasinghege; Majed Mordaa; Roberta Mandile; Maria Vittoria Barone; Merlin Nanayakkara

doi:10.3389/fmed.2023.1085578

The protective role of Lactobacillus rhamnosus GG postbiotic on the alteration of autophagy and inflammation pathways induced by gliadin in intestinal models

Front Med (Lausanne). 2023 May 4:10:1085578. doi: 10.3389/fmed.2023.1085578. eCollection 2023.

Affiliations

¹ Department of Translational Medical Science (Section of Paediatrics), University of Naples Federico II, Naples, Italy.
² Department of Translational Medical Sciences, School of Medicine and Surgery, University of Naples Federico II, Naples, Italy.
³ European Laboratory for the Investigation of Food Induced Diseases (ELFID), University of Naples Federico II, Naples, Italy.

^# Contributed equally.

Abstract

Celiac disease (CD) is an autoimmune enteropathy caused by an abnormal immune response to gliadin peptides in genetically predisposed individuals. For people with CD, the only available therapy thus far is the lifelong necessity for a gluten-free diet (GFD). Innovative therapies include probiotics and postbiotics as dietary supplements, both of which may benefit the host. Therefore, the present study aimed to investigate the possible beneficial effects of the postbiotic Lactobacillus rhamnosus GG (LGG) in preventing the effects induced by indigested gliadin peptides on the intestinal epithelium. In this study, these effects on the mTOR pathway, autophagic function, and inflammation have been evaluated. Furthermore, in this study, we stimulated the Caco-2 cells with the undigested gliadin peptide (P31-43) and with the crude gliadin peptic-tryptic peptides (PTG) and pretreated the samples with LGG postbiotics (ATCC 53103) (1 × 108). In this study, the effects induced by gliadin before and after pretreatment have also been investigated. The phosphorylation levels of mTOR, p70S6K, and p4EBP-1 were increased after treatment with PTG and P31-43, indicating that the intestinal epithelial cells responded to the gliadin peptides by activating the mTOR pathway. Moreover, in this study, an increase in the phosphorylation of NF-κβ was observed. Pretreatment with LGG postbiotic prevented both the activation of the mTOR pathway and the NF-κβ phosphorylation. In addition, P31-43 reduced LC3II staining, and the postbiotic treatment was able to prevent this reduction. Subsequently, to evaluate the inflammation in a more complex intestinal model, the intestinal organoids derived from celiac disease patient biopsies (GCD-CD) and controls (CTR) were cultured. Stimulation with peptide 31-43 in the CD intestinal organoids induced NF-κβ activation, and pretreatment with LGG postbiotic could prevent it. These data showed that the LGG postbiotic can prevent the P31-43-mediated increase in inflammation in both Caco-2 cells and in intestinal organoids derived from CD patients.

Keywords: autophagy; gliadin; inflammation; organoids; p31-43; postbiotic.

Grants and funding

The work was partially supported by Dicofarm S.p.A. with a specific contribution to the European Laboratory for the Research of Food-Induced Diseases (ELFID). However, Dicofarm S.p.A. had no role in (1) the design of the study, (2) the collection, analysis, and interpretation of the data, (3) the writing of the manuscript, and (4) the decision to submit the manuscript for the publication. The authors have no other conflicts of interest directly relevant to the content of this manuscript, which remains their sole responsibility. The work was also supported by a project funded by the National Recovery and Resilience Plan (NRRP), Mission 4 Component 2 Investment 1.3—Call for Proposals No. 341 of 15 March 2022 of the Italian Ministry of University and Research funded by the European Union—Next Generation EU; Award No. Project code PE00000003, Concession Decree No. 1550 of 11 October 2022 adopted by the Italian Ministry of University and Research, CUP D93C22000890001, Project title ON Foods—Research and innovation network on food and nutrition sustainability, safety and security—Working ON foods.