title: Altered expression pattern of molecular factors involved in colonic smooth muscle functions: an immunohistochemical study in patients with diverticular disease.
abstract: BACKGROUND
  The pathogenesis of diverticular disease (DD) is thought to result from complex interactions among dietary habits, genetic factors and coexistence of other bowel abnormalities. These conditions lead to alterations in colonic pressure and motility, facilitating the formation of diverticula. Although electrophysiological studies on smooth muscle cells (SMCs) have investigated colonic motor dysfunctions, scarce attention has been paid to their molecular abnormalities, and data on SMCs in DD are lacking. Accordingly, the main purpose of this study was to evaluate the expression patterns of molecular factors involved in the contractile functions of SMCs in the tunica muscularis of colonic specimens from patients with DD.
  
  
  RESULTS
  By means of immunohistochemistry and image analysis, we examined the expression of Cx26 and Cx43, which are prominent components of gap junctions in human colonic SMCs, as well as pS368-Cx43, PKCps, RhoA and αSMA, all known to regulate the functions of gap junctions and the contractile activity of SMCs. The immunohistochemical analysis revealed significant abnormalities in DD samples, concerning both the expression and distribution patterns of most of the investigated molecular factors.
  
  
  CONCLUSIONS
  This study demonstrates, for the first time, that an altered pattern of factors involved in SMC contractility is present at level of the tunica muscularis of DD patients. Moreover, considering that our analysis was conducted on colonic tissues not directly affected by diverticular lesions or inflammatory reactions, it is conceivable that these molecular alterations may precede and predispose to the formation of diverticula, rather than being mere consequences of the disease.
authors: Unit of Histology and Medical Embriology, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy. letizia.mattii@med.unipi.it
authors: Letizia
authors: L
authors: Mattii
authors: Chiara
authors: C
authors: Ippolito
authors: Cristina
authors: C
authors: Segnani
authors: Barbara
authors: B
authors: Battolla
authors: Rocchina
authors: R
authors: Colucci
authors: Amelio
authors: A
authors: Dolfi
authors: Gabrio
authors: G
authors: Bassotti
authors: Corrado
authors: C
authors: Blandizzi
authors: Nunzia
authors: N
authors: Bernardini
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003106:Colon / Q000378:metabolism* / Q000473:pathology; D000072259:Connexin 26; D018031:Connexin 43 / Q000235:genetics / Q000378:metabolism; D017630:Connexins / Q000235:genetics / Q000378:metabolism; D004241:Diverticulum, Colon / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009130:Muscle, Smooth / Q000378:metabolism* / Q000473:pathology; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics / Q000378:metabolism; D020742:rhoA GTP-Binding Protein / Q000235:genetics / Q000378:metabolism
chemical_list: D018031:Connexin 43; D017630:Connexins; C000607042:GJB2 protein, human; D000072259:Connexin 26; D019009:Proto-Oncogene Proteins c-kit; D011493:Protein Kinase C; D020742:rhoA GTP-Binding Protein