I Sukhotnik1,2, Y Ben Shahar3,4, Y Pollak3, T Dorfman3, H Kreizman Shefer3, Z E Assi3,4, N Mor-Vaknin5, A G Coran6. 1. Laboratory of Intestinal Adaptation and Recovery, The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel. igor-dr@internet-zahav.net. 2. Department of Pediatric Surgery, Bnai Zion Medical Center, Golomb St., P.O.B. 4940, 31048, Haifa, Israel. igor-dr@internet-zahav.net. 3. Laboratory of Intestinal Adaptation and Recovery, The Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel. 4. Department of Pediatric Surgery, Bnai Zion Medical Center, Golomb St., P.O.B. 4940, 31048, Haifa, Israel. 5. Department of Internal Medicine, C.S. Mott Children's Hospital, University of Michigan Medical School, Ann Arbor, Michigan, USA. 6. Section of Pediatric Surgery, C.S. Mott Children's Hospital, University of Michigan Medical School, Ann Arbor, Michigan, USA.
Abstract
PURPOSE: Intermediate filaments (IFs) are a part of the cytoskeleton that extend throughout the cytoplasm of all cells and function in the maintenance of cell-shape by bearing tension and serving as structural components of the nuclear lamina. In normal intestine, IFs provide a tissue-specific three-dimensional scaffolding with unique context-dependent organizational features. The purpose of this study was to evaluate the role of IFs during intestinal adaptation in a rat model of short bowel syndrome (SBS). MATERIALS AND METHODS: Male rats were divided into two groups: Sham rats underwent bowel transection and SBS rats underwent a 75% bowel resection. Parameters of intestinal adaptation, enterocyte proliferation and apoptosis were determined 2 weeks after operation. Illumina's Digital Gene Expression (DGE) analysis was used to determine the cytoskeleton-related gene expression profiling. IF-related genes and protein expression were determined using real-time PCR, Western blotting and immunohistochemistry. RESULTS: Massive small bowel resection resulted in a significant increase in enterocyte proliferation and concomitant increase in cell apoptosis. From the total number of 20,000 probes, 16 cytoskeleton-related genes were investigated. Between these genes, only myosin and tubulin levels were upregulated in SBS compared to sham animals. Between IF-related genes, desmin, vimentin and lamin levels were down-regulated and keratin and neurofilament remain unchanged. The levels of TGF-β, vimentin and desmin gene and protein were down-regulated in resected rats (vs sham animals). CONCLUSIONS: Two weeks following massive bowel resection in rats, the accelerated cell turnover was accompanied by a stimulated microfilaments and microtubules, and by inhibited intermediate filaments. Resistance to cell compression rather that maintenance of cell-shape by bearing tension are responsible for contraction, motility and postmitotic cell separation in a late stage of intestinal adaptation.
PURPOSE: Intermediate filaments (IFs) are a part of the cytoskeleton that extend throughout the cytoplasm of all cells and function in the maintenance of cell-shape by bearing tension and serving as structural components of the nuclear lamina. In normal intestine, IFs provide a tissue-specific three-dimensional scaffolding with unique context-dependent organizational features. The purpose of this study was to evaluate the role of IFs during intestinal adaptation in a rat model of short bowel syndrome (SBS). MATERIALS AND METHODS: Male rats were divided into two groups: Sham rats underwent bowel transection and SBSrats underwent a 75% bowel resection. Parameters of intestinal adaptation, enterocyte proliferation and apoptosis were determined 2 weeks after operation. Illumina's Digital Gene Expression (DGE) analysis was used to determine the cytoskeleton-related gene expression profiling. IF-related genes and protein expression were determined using real-time PCR, Western blotting and immunohistochemistry. RESULTS: Massive small bowel resection resulted in a significant increase in enterocyte proliferation and concomitant increase in cell apoptosis. From the total number of 20,000 probes, 16 cytoskeleton-related genes were investigated. Between these genes, only myosin and tubulin levels were upregulated in SBS compared to sham animals. Between IF-related genes, desmin, vimentin and lamin levels were down-regulated and keratin and neurofilament remain unchanged. The levels of TGF-β, vimentin and desmin gene and protein were down-regulated in resected rats (vs sham animals). CONCLUSIONS: Two weeks following massive bowel resection in rats, the accelerated cell turnover was accompanied by a stimulated microfilaments and microtubules, and by inhibited intermediate filaments. Resistance to cell compression rather that maintenance of cell-shape by bearing tension are responsible for contraction, motility and postmitotic cell separation in a late stage of intestinal adaptation.
Authors: C Schaeffer; M Diab-Assef; M Plateroti; F Laurent-Huck; J M Reimund; M Kedinger; C Foltzer-Jourdainne Journal: Gut Date: 2000-08 Impact factor: 23.059