Executioner caspases 3 and 7 are dispensable for intestinal epithelium turnover and homeostasis at steady state

Ghazavi, Farzaneh; Huysentruyt, Jelle; De Coninck, Jordy; Kourula, Stephanie; Martens, Sofie; Hassannia, Behrouz; Wartewig, Tim; Divert, Tatyana; Roelandt, Ria; Popper, Bastian; Hiergeist, Andreas; Tougaard, Peter; Berghe, Tom Vanden; Joossens, Marie; Berx, Geert; Takahashi, Nozomi; Wahida, Adam und Vandenabeele, Peter (2022): Executioner caspases 3 and 7 are dispensable for intestinal epithelium turnover and homeostasis at steady state. In: Proceedings of the National Academy of Sciences of the United States of America, Bd. 119, Nr. 6, e2024508119

Abstract

Apoptosis is widely believed to be crucial for epithelial cell death and shedding in the intestine, thereby shaping the overall architecture of the gastrointestinal tract, but also regulating tolerance induction, pinpointing a role of apoptosis intestinal epithelial cell (IEC) turnover and maintenance of barrier function, and in maintaining immune homeostasis. To experimentally address this concept, we generated IEC-specific knockout mice that lack both executioner caspase-3 and caspase-7 (Casp3/7(Delta IEC)), which are the converging point of the extrinsic and intrinsic apoptotic pathway. Surprisingly, the overall architecture, cellular landscape, and proliferation rate remained unchanged in these mice. However, nonapoptotic cell extrusion was increased in Casp3/7(Delta IEC) mice, compensating apoptosis deficiency, maintaining the same physiological level of IEC shedding. Microbiome richness and composition stayed unaffected, bearing no sign of dysbiosis. Transcriptome and single-cell RNA sequencing analyses of IECs and immune cells revealed no differences in signaling pathways of differentiation and inflammation. These findings demonstrate that during homeostasis, apoptosis per se is dispensable for IEC turnover at the top of intestinal villi intestinal tissue dynamics, microbiome, and immune cell composition.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Medizin
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• ISSN: 0027-8424
• Sprache: Englisch
• DFG: Gefördert durch die Deutsche Forschungsgemeinschaft (DFG) - 395357507