scholarly journals X-linked Inhibitor of Apoptosis Protein Functions as a Cofactor in Transforming Growth Factor-β Signaling

2001 ◽  
Vol 276 (28) ◽  
pp. 26542-26549 ◽  
Author(s):  
Stephanie Birkey Reffey ◽  
Jens U. Wurthner ◽  
W. Tony Parks ◽  
Anita B. Roberts ◽  
Colin S. Duckett
Keyword(s):  
Growth Factor ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
Inhibitor Of Apoptosis ◽  
Inhibitor Of Apoptosis Protein ◽  
Apoptosis Protein ◽  
Protein Functions

Cellular inhibitor of apoptosis protein 2 controls human colonic epithelial restitution, migration, and Rac1 activation

2015 ◽  
Vol 308 (2) ◽  
pp. G92-G99 ◽  
Author(s):  
Jakob Benedict Seidelin ◽  
Sylvester Larsen ◽  
Dorte Linnemann ◽  
Ben Vainer ◽  
Mehmet Coskun ◽  
...  
Keyword(s):  
Wound Healing ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
Human Colon ◽  
Inhibitor Of Apoptosis ◽  
Experimental Ulcer ◽  
Inhibitor Of Apoptosis Protein ◽  
Apoptosis Protein

Identification of pathways involved in wound healing is important for understanding the pathogenesis of various intestinal diseases. Cellular inhibitor of apoptosis protein 2 (cIAP2) regulates proliferation and migration in nonepithelial cells and is expressed in human colonocytes. The aim of the study was to investigate the role of cIAP2 for wound healing in the normal human colon. Wound tissue was generated by taking rectosigmoidal biopsies across an experimental ulcer in healthy subjects after 5, 24, and 48 h. In experimental ulcers, the expression of cIAP2 in regenerating intestinal epithelial cells (IECs) was increased at the wound edge after 24 h ( P < 0.05), returned to normal after reepithelialization, and correlated with the inflammatory reaction in the experimental wounds ( P < 0.001). cIAP2 was induced in vitro in regenerating Caco2 IECs after wound infliction ( P < 0.01). Knockdown of cIAP2 caused a substantial impairment of the IEC regeneration through inhibition of migration ( P < 0.005). cIAP2 overexpression lead to formation of migrating IECs and upregulation of expression of RhoA and Rac1 as well as GTP-activation of Rac1. Transforming growth factor-β1 enhanced the expression of cIAP2 but was not upregulated in wounds in vivo and in vitro. NF-κB and MAPK pathways did not affect cIAP2 expression. cIAP2 is in conclusion a regulator of human intestinal wound healing through enhanced migration along with activation of Rac1, and the findings suggest that cIAP2 could be a future therapeutic target to improve intestinal wound healing.

X-linked inhibitor of apoptosis protein (XIAP) inhibition in systemic sclerosis (SSc)

2021 ◽  
pp. annrheumdis-2020-219822
Author(s):  
Christina Bergmann ◽  
Ludwig Hallenberger ◽  
Sara Chenguiti Fakhouri ◽  
Benita Merlevede ◽  
Amelie Brandt ◽  
...  
Keyword(s):  
Systemic Sclerosis ◽  
Transforming Growth Factor Beta ◽  
Topoisomerase I ◽  
Transforming Growth Factor ◽  
Inhibitor Of Apoptosis ◽  
Dependent Manner ◽  
Cultured Fibroblasts ◽  
Multifunctional Protein ◽  
Inhibitor Of Apoptosis Protein ◽  
Apoptosis Protein

ObjectiveX-linked inhibitor of apoptosis protein (XIAP) is a multifunctional protein with important functions in apoptosis, cellular differentiation and cytoskeletal organisation and is emerging as potential target for the treatment of various cancers. The aim of the current study was to investigate the role of XIAP in the pathogenesis of systemic sclerosis (SSc).MethodsThe expression of XIAP in human skin samples of patients with SSc and chronic graft versus host disease (cGvHD) and healthy individuals was analysed by quantitative PCR, immunofluorescence (IF) and western blot. XIAP was inactivated by siRNA-mediated knockdown and pharmacological inhibition. The effects of XIAP inactivation were analysed in cultured fibroblasts and in the fibrosis models bleomycin-induced and topoisomerase-I-(topoI)-induced fibrosis and in Wnt10b-transgenic mice.ResultsThe expression of XIAP, but not of other inhibitor of apoptosis protein family members, was increased in fibroblasts in SSc and sclerodermatous cGvHD. Transforming growth factor beta (TGF-β) induced the expression of XIAP in a SMAD3-dependent manner. Inactivation of XIAP reduced WNT-induced fibroblast activation and collagen release. Inhibition of XIAP also ameliorated fibrosis induced by bleomycin, topoI and overexpression of Wnt10b in well-tolerated doses. The profibrotic effects of XIAP were mediated via WNT/β-catenin signalling. Inactivation of XIAP reduces binding of β-catenin to TCF to in a TLE-dependent manner to block WNT/β-catenin-dependent transcription.ConclusionsOur data characterise XIAP as a novel link between two core pathways of fibrosis. XIAP is overexpressed in SSc and cGvHD in a TGF-β/SMAD3-dependent manner and in turn amplifies the profibrotic effects of WNT/β-catenin signalling on fibroblasts via transducin-like enhancer of split 3. Targeted inactivation of XIAP inhibits the aberrant activation of fibroblasts in murine models of SSc.

Perianale Fisteln bei CED: vom Mausmodell zur Klinik

2018 ◽  
Vol 75 (5) ◽  
pp. 287-294
Author(s):  
Michael Scharl
Keyword(s):  
Growth Factor ◽  
Morbus Crohn ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
Interleukin 13

Zusammenfassung. Fisteln stellen nach wie vor eine der wichtigsten Komplikationen bei Patienten mit Morbus Crohn dar. Bei mindestens einem Drittel aller Morbus Crohn Patienten treten im Laufe der Erkrankung Fisteln auf. Eine dauerhafte Heilung der Fistel wird jedoch, auch unter Ausschöpfung sämtlicher medikamentöser und chirurgischer Therapieoptionen, nur in rund einem Drittel dieser Patienten erreicht. Der genaue molekulare Mechanismus der Fistelentstehung ist bis heute nicht ganz klar. Aus histopathologischer Sichtweise stellen Fisteln eine röhrenartige Struktur dar, welche von flachen epithelartigen Zellen ausgekleidet ist. Als ursächlicher Entstehungsmechanismus wird dabei die sogenannte epitheliale-zu-mesenchymale Transition (EMT) angesehen und es kann eine starke Expression der Entzündungsmediatoren Tumor Nekrose Faktor, Interleukin-13 und Transforming Growth Factor β in den Fistelarealen nachgewiesen werden. Zusätzlich zu den bereits etablierten, medikamentösen Therapieoptionen, also Antibiotika, Immunmodulatoren und anti-TNF Antikörper, stellt insbesondere der Einsatz der mesenchymalen Stammzelltherapie einen erfolgversprechenden Therapieansatz für die Zukunft dar.

Sign in / Sign up

Export Citation Format

Share Document