Genetically engineered E. coli Nissle attenuates hyperammonemia and prevents memory impairment in bile‐duct ligated rats


Article
Version acceptée / Accepted Manuscript

Date de publication

Identifiant ORCID de l’auteur

Contributrices et contributeurs

Direction de recherche

Publié dans

Liver international

Date de la Conférence

Lieu de la Conférence

Éditeur

Wiley

Cycle d'études

Programme

Mots-clés

  • Ammonia
  • Arginine
  • Bile‐duct ligature
  • Butyrate
  • Cirrhosis
  • E. coli Nissle
  • Hepatic encephalopathy
  • Inflammation
  • Memory
  • Probiotics

Organisme subventionnaire

Résumé

Résumé

Hyperammonemia associated with chronic liver disease (CLD) is implicated in the pathogenesis of hepatic encephalopathy (HE). The gut is a major source of ammonia production that contributes to hyperammonemia in CLD and HE and remains the primary therapeutic target for lowering hyperammonemia. As an ammonia‐lowering strategy, Escherichia coli Nissle 1917 bacterium was genetically modified to consume and convert ammonia to arginine (S‐ARG). S‐ARG was further modified to additionally synthesize butyrate (S‐ARG+BUT). Both strains were evaluated in bile‐duct ligated (BDL) rats; experimental model of CLD and HE. Methods One‐week post‐surgery, BDLs received non‐modified EcN (EcN), S‐ARG, S‐ARG+BUT (3x1011 CFU/day) or vehicle until sacrifice at 3‐ or 5‐weeks. Plasma (ammonia/pro‐inflammatory/liver‐function), liver fibrosis (hydroxyproline), liver mRNA (pro‐inflammatory/fibrogenic/anti‐apoptotic) and colon mRNA (pro‐inflammatory) biomarkers were measured post‐sacrifice. Memory, motor‐coordination, muscle‐strength, and locomotion were assessed at 5‐weeks. Results In BDL‐Veh rats, hyperammonemia developed at 3‐ and further increased at 5‐weeks. This rise was prevented by S‐ARG and S‐ARG+BUT, whereas EcN was ineffective. Memory impairment was prevented only in S‐ARG+BUT vs BDL‐Veh. Systemic inflammation (IL‐10/MCP‐1/endotoxin) increased at 3‐ and 5‐weeks in BDL‐Veh. S‐ARG+BUT attenuated inflammation at both timepoints (except 5‐week endotoxin) vs BDL‐Veh, whereas S‐ARG only attenuated IP‐10 and MCP‐1 at 3‐weeks. Circulating (ALT/AST/ALP/GGT/albumin/bilirubin) and gene expression liver‐function markers (IL‐10/IL‐6/IL‐1β/TGF‐β/α‐SMA/collagen‐1α1/Bcl‐2) were not normalized by either strain. Colonic mRNA (TNF‐α/IL‐1β/occludin) markers were attenuated by synthetic strains at both timepoints vs BDL‐Veh. Conclusion S‐ARG and S‐ARG+BUT attenuated hyperammonemia, with S‐ARG+BUT additional memory protection likely due to greater anti‐inflammatory effect. These innovative strategies, particularly S‐ARG+BUT, have potential to prevent HE.

Table des matières

Notes

Notes

Autre version linguistique

Ensemble de données lié

Licence

Approbation

Évaluation

Complété par

Référencé par

Ce document diffusé sur Papyrus est la propriété exclusive des titulaires des droits d'auteur et est protégé par la Loi sur le droit d'auteur (L.R.C. (1985), ch. C-42). Sauf si le document est diffusé sous une licence Creative Commons, il ne peut être utilisé que dans le cadre d'une utilisation équitable et non commerciale comme le prévoit la Loi (i.e. à des fins d'étude privée ou de recherche, de critique ou de compte-rendu). Pour toute autre utilisation, une autorisation écrite des titulaires des droits d'auteur sera nécessaire.