benzyloxycarbonylvalyl-alanyl-aspartyl-fluoromethyl-ketone and Crohn-Disease

Necroptosis is an inflammatory form of programmed cell death requiring receptor-interacting protein kinase 3 (RIP3) and mixed lineage kinase domain-like protein (MLKL).. The aim of this study is to examine in depth in vitro and ex vivo the contribution of necroptosis to intestinal inflammation.. In vitro: we used an intestinal cell line, HCT116RIP3, produced in our laboratory and overexpressing RIP3. Ex vivo: intestinal mucosal biopsies were taken from patients with inflammatory bowel disease (IBD) (20 with Crohn's disease; 20 with ulcerative colitis) and from 20 controls.. RIP3-induced necroptosis triggers MLKL activation, increases cytokine/alarmin expression (IL-8, IL-1β, IL-33, HMGB1), NF-kBp65 translocation and NALP3 inflammasome assembly. It also affects membrane permeability by altering cell-cell junctional proteins (E-cadherin, Occludin, Zonulin-1). Targeting necroptosis through Necrostatin-1 significantly reduces intestinal inflammation in vitro and in cultured intestinal explants from IBD.. We show for the first time in vitro and ex vivo that RIP3-driven necroptosis seriously affects intestinal inflammation by increasing pMLKL, activating different cytokines and alarmins, and altering epithelial permeability. The inhibition of necroptosis causes a significant decrease of all these effects. These data strongly support the view that targeting necroptosis may represent a promising new option for the treatment of inflammatory enteropathies.

Topics: Adolescent; Amino Acid Chloromethyl Ketones; Apoptosis; Cadherins; Caspase 1; Cell Adhesion; Cell Membrane Permeability; Cell Survival; Child; Child, Preschool; Colitis, Ulcerative; Crohn Disease; Epithelial Cells; HCT116 Cells; HMGB1 Protein; Humans; Imidazoles; Indoles; Inflammasomes; Inflammation; Interleukin-1beta; Interleukin-8; Intestinal Mucosa; Necrosis; NLR Family, Pyrin Domain-Containing 3 Protein; Phosphorylation; Protein Kinases; Protein Transport; Receptor-Interacting Protein Serine-Threonine Kinases; RNA, Messenger; Transcription Factor RelA; Tumor Necrosis Factor-alpha