Javier Conde1, Clara Ruiz-Fernandez1, Vera Francisco1, Morena Scotece1, Rodolfo Gómez2, Francisca Lago3, Miguel Angel Gonzalez-Gay4, Jesús Pino1, Ali Mobasheri5, Oreste Gualillo1. 1. SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), the NEIRID Lab (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Santiago de Compostela, Spain. 2. Musculoskeletal Pathology Laboratory, Institute IDIS, Santiago University Clinical Hospital, Santiago de Compostela, Spain. 3. Molecular and Cellular Cardiology Group, SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), Santiago University Clinical Hospital, Santiago de Compostela, Spain. 4. Epidemiology, Genetics and Atherosclerosis Research Group on Systemic Inflammatory Diseases, Universidad de Cantabria and IDIVAL, Hospital Universitario Marqués de Valdecilla, Santander, Spain. 5. Department of Regenerative Medicine, State Research Institute Centre for Innovative Medicine, Vilnius, Lithuania.
Abstract
OBJECTIVE: Osteoarthritis (OA) is an age-related biomechanical and low-grade inflammometabolic disease of the joints and one of the costliest and disabling forms of arthritis. Studies on matrix-degrading enzymes such as metalloproteases, which are implicated in the increased catabolism of extracellular matrix, are of paramount relevance. DKK3 is a member of DKK family and is best known for its role in cancer. Although there is some information about the participation of DKK3 in cartilage pathophysiology and on metalloproteases regulation, in particular, little is known about DKK3 signaling mechanisms. Thus, the aim of this study is to explore how DKK3 regulates matrix metalloproteinase-13 (MMP-13) expression. DESIGN: Gene, protein expression and protein phosphorylation in primary human chondrocytes and ATDC5 mouse cells were assessed by RT-qPCR and Western blot analysis. Further studies on DKK3 activity were performed by targeting DKK3 gene with a specific siRNA. RESULTS: DKK3 expression was found to be higher in OA human chondrocytes than healthy cells, being its expression decreased in interleukin-1α (IL-1α)-stimulated cells. DKK3 knockdown increased the induction of MMP-13 elicited by IL-1α in human and mouse chondrocytes and after the analysis of different signalling pathways, we observed that NF-κB pathway was involved in the regulation of MMP-13 expression by DKK3. CONCLUSIONS: Herein we have demonstrated, for the first time, that DKK3 gene silencing exacerbated NF-κB activation, resulting in an increased IL-1α-driven induction of MMP-13. Our results further confirm that DKK3 may play a protective role in OA by attenuating NF-κB activation and the subsequent production of metalloproteases.
OBJECTIVE: Osteoarthritis (OA) is an age-related biomechanical and low-grade inflammometabolic disease of the joints and one of the costliest and disabling forms of arthritis. Studies on matrix-degrading enzymes such as metalloproteases, which are implicated in the increased catabolism of extracellular matrix, are of paramount relevance. DKK3 is a member of DKK family and is best known for its role in cancer. Although there is some information about the participation of DKK3 in cartilage pathophysiology and on metalloproteases regulation, in particular, little is known about DKK3 signaling mechanisms. Thus, the aim of this study is to explore how DKK3 regulates matrix metalloproteinase-13 (MMP-13) expression. DESIGN: Gene, protein expression and protein phosphorylation in primary human chondrocytes and ATDC5 mouse cells were assessed by RT-qPCR and Western blot analysis. Further studies on DKK3 activity were performed by targeting DKK3 gene with a specific siRNA. RESULTS: DKK3 expression was found to be higher in OA human chondrocytes than healthy cells, being its expression decreased in interleukin-1α (IL-1α)-stimulated cells. DKK3 knockdown increased the induction of MMP-13 elicited by IL-1α in human and mouse chondrocytes and after the analysis of different signalling pathways, we observed that NF-κB pathway was involved in the regulation of MMP-13 expression by DKK3. CONCLUSIONS: Herein we have demonstrated, for the first time, that DKK3 gene silencing exacerbated NF-κB activation, resulting in an increased IL-1α-driven induction of MMP-13. Our results further confirm that DKK3 may play a protective role in OA by attenuating NF-κB activation and the subsequent production of metalloproteases.
Authors: Kenneth B Marcu; Miguel Otero; Eleonora Olivotto; Rosa Maria Borzi; Mary B Goldring Journal: Curr Drug Targets Date: 2010-05 Impact factor: 3.465
Authors: R Lago; R Gomez; M Otero; F Lago; R Gallego; C Dieguez; J J Gomez-Reino; O Gualillo Journal: Osteoarthritis Cartilage Date: 2008-02-07 Impact factor: 6.576