الفهرس | Only 14 pages are availabe for public view |
Abstract Ulcerative colitis is a chronic inflammatory disease of the rectum and colon . Results from many studies in people and animals of intestinal inflammation suggest that ulcerative colitis results from environmental factors triggering a loss of tolerance for normal intestinal flora in genetically susceptible individuals. The timely breakdown of extracellular matrix (ECM) is essential for embryonic development, morphogenesis, reproduction, and tissue resorption and remodeling. The matrix metalloproteinases (MMPs) also called matrixins are thought to play a central role in these processes. The expression of most matrixins is transcriptionally regulated by growth factors, hormones, cytokines, and cellular transformation. The proteolytic activities of MMPs are precisely controlled during activation from their precursors and inhibition by endogenous inhibitors, α-macroglobulins , and tissue inhibitors of metalloproteinases (timps). Degradation and remodelling of the extra cellular matrix (ECM) is increasingly implicated in the pathogenesis of many inflammatory diseases such as inflammatory bowel disease, MMPs play a key role in these events. MMPs can cleave all components of the ECM and in health act in harmony as part of normal tissue turn over. During inflammation their dysregulation leads to excess degradation of the matrix components and loss of tissue integrity. MMPs are released from almost all connective tissue cells in response to inflammatory stimuli such as cytokines The plasma mean concentration of MMP3 & MMP9 in ulcerative colitis is increasing according to disease activity so can be used as a bio marker of disease activity In conclusion, our informations confirm the role of both MMP-3 and MMP-9 in the pathogenesis of ulcerative colitis. However may be useful as a biomarker of the disease activity. |