title: TGF-beta1 reverses the effects of matrix anchorage on the gene expression of decorin and procollagen type I in tendon fibroblasts.
abstract: Transforming growth factor-beta1 is known for its effect on the production of extracellular matrix in tendons. Elevated levels of transforming growth factor-beta1 have been reported in tendon adhesion and tendinosis, which suggests that transforming growth factor-beta1 plays an important role in matrix disturbances. Tendon adhesion involves excessive collagen deposition, whereas tendinosis is associated with increased proteoglycan deposition. It seems that other factors also may affect matrix deposition and modulate the effects of transforming growth factor-beta1. We assessed whether matrix anchorage to Type I collagen or fibronectin could change the gene expression of matrix proteins in tendon fibroblasts, and studied whether the effects of transforming growth factor-beta1 were altered by matrix anchorage. Human patellar tendon fibroblast cultures were prepared in different cell anchorages, and the cellular responses to transforming growth factor-beta1 were measured as gene expression of procollagen Type I, Type III, decorin, and biglycan by real-time reverse transcriptase-polymerase chain reaction. Fibronectin anchorage significantly increased the messenger ribonucleic acid level of decorin, and the messenger ribonucleic acid level of procollagen Type I was decreased by matrix anchorage to either fibronectin or Type I collagen. Transforming growth factor-beta1 increased the messenger ribonucleic acid level of procollagen Type I in Type I collagen-coated plates, but it suppressed the messenger ribonucleic acid level of decorin in fibronectin-coated plates. These findings suggest that interaction of matrix anchorage and transforming growth factor-beta1 is an important determinant of matrix deposition in healing tendons and the development of matrix disturbances in tendons.
authors.affiliation: Department of Orthopaedics & Traumatology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong.
authors.forename: Sai-Chuen
authors.initials: SC
authors.lastname: Fu
authors.forename: Yim-Ping
authors.initials: YP
authors.lastname: Wong
authors.forename: Yau-Chuk
authors.initials: YC
authors.lastname: Cheuk
authors.forename: Kwong-Man
authors.initials: KM
authors.lastname: Lee
authors.forename: Kai-Ming
authors.initials: KM
authors.lastname: Chan
mesh_terms: D002478:Cells, Cultured; D024042:Collagen Type I / Q000737:chemistry / Q000378:metabolism*; D058575:Decorin; D005109:Extracellular Matrix / Q000187:drug effects* / Q000378:metabolism; D016326:Extracellular Matrix Proteins; D005347:Fibroblasts / Q000378:metabolism*; D005353:Fibronectins / Q000494:pharmacology; D015870:Gene Expression; D006801:Humans; D011509:Proteoglycans / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D013710:Tendons / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D053773:Transforming Growth Factor beta1
chemical_list: D024042:Collagen Type I; C546878:DCN protein, human; D058575:Decorin; D016326:Extracellular Matrix Proteins; D005353:Fibronectins; D011509:Proteoglycans; D012333:RNA, Messenger; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1