Ontology highlight
ABSTRACT: Objective
Decreased expression of collagen type II in favour of collagen type I or X is one hallmark of chondrocyte phenotype changes in osteoarthritic (OA) cartilage. MicroRNA- (miR-) 29b was previously shown to target collagens in several tissues. We studied whether it could contribute to collagen imbalance in chondrocytes with an impaired phenotype.Methods
After preliminary microarrays screening, miR-29b levels were measured by RT- quantitative PCR in in vitro models of chondrocyte phenotype changes (IL-1? challenge or serial subculturing) and in chondrocytes from OA and non-OA patients. Potential miR-29b targets identified in silico in 3'-UTRs of collagens mRNAs were tested with luciferase reporter assays. The impact of premiR-29b overexpression in ATDC5 cells was studied on collagen mRNA levels and synthesis (Sirius red staining) during chondrogenesis.Results
MiR-29b level increased significantly in IL-1?-stimulated and weakly in subcultured chondrocytes. A 5.8-fold increase was observed in chondrocytes from OA versus non-OA patients. Reporter assays showed that miR-29b targeted COL2A1 and COL1A2 3'-UTRs although with a variable recovery upon mutation. In ATDC5 cells overexpressing premiR-29b, collagen production was reduced while mRNA levels increased.Conclusions
By acting probably as a posttranscriptional regulator with a different efficacy on COL2A1 and COL1A2 expression, miR-29b can contribute to the collagens imbalance associated with an abnormal chondrocyte phenotype.
SUBMITTER: Moulin D
PROVIDER: S-EPMC5458373 | biostudies-literature | 2017
REPOSITORIES: biostudies-literature
Moulin David D Salone Véronique V Koufany Meriem M Clément Thomas T Behm-Ansmant Isabelle I Branlant Christiane C Charpentier Bruno B Jouzeau Jean-Yves JY
BioMed research international 20170522
<h4>Objective</h4>Decreased expression of collagen type II in favour of collagen type I or X is one hallmark of chondrocyte phenotype changes in osteoarthritic (OA) cartilage. MicroRNA- (miR-) 29b was previously shown to target collagens in several tissues. We studied whether it could contribute to collagen imbalance in chondrocytes with an impaired phenotype.<h4>Methods</h4>After preliminary microarrays screening, miR-29b levels were measured by RT- quantitative PCR in <i>in vitro</i> models of ...[more]