Differential uPA expression by TGF-beta1 in gingival fibroblasts.
Transforming Growth Factor-beta1 (TGF-beta1) plays a key role in connective tissue remodeling and inflammation. Under pathological conditions, like periodontal disease, fibroblasts may display an altered response to this growth factor. To investigate this question, we have studied whether TGF-beta1 may differentially regulate the expression of urokinase at the protein level in primary cultures of fibroblasts derived from healthy gingiva, granulation tissue from gingival wounds, and chronic periodontal disease. We observed that TGF-beta1 may repress urokinase expression in healthy gingival fibroblasts and promote its production in granulation-tissue fibroblasts. A significant correlation was found between expression of the myofibroblast marker alpha-smooth-muscle actin and stimulation of urokinase production by TGF-beta1. Immunostaining of gingival wounds showed that myofibroblasts were involved in urokinase production. TGF-beta1-stimulated urokinase expression was blocked after inhibition of the c-jun-NH2 terminal kinase signaling pathway. We propose that stimulation of urokinase production by TGF-beta1 is involved in the responses of activated fibroblasts to tissue injury.
Smith
P C
PC
Faculty of Odontology, Institute of Nutrition and Food Technology (INTA), University of Chile, Olivos 943, Casilla 1903, Santiago, Chile. patricio.smith@gmail.com
Martínez
J
J
D000199:Actins / Q000096:biosynthesis; D048868:Adaptor Proteins, Signal Transducing / Q000502:physiology; D000328:Adult; D016022:Case-Control Studies; D002478:Cells, Cultured; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D005881:Gingiva / Q000166:cytology / Q000293:injuries / Q000378:metabolism*; D006097:Granulation Tissue / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000502:physiology; D020935:MAP Kinase Signaling System; D008297:Male; D010510:Periodontal Diseases / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000502:physiology*; D053773:Transforming Growth Factor beta1; D014568:Urokinase-Type Plasminogen Activator / Q000096:biosynthesis*; D014945:Wound Healing / Q000502:physiology
D000199:Actins; D048868:Adaptor Proteins, Signal Transducing; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D048031:JNK Mitogen-Activated Protein Kinases; D014568:Urokinase-Type Plasminogen Activator