| First Author | Kamiya Y | Year | 2013 |
| Journal | J Bone Miner Res | Volume | 28 |
| Issue | 5 | Pages | 1127-34 |
| PubMed ID | 23197372 | Mgi Jnum | J:222339 |
| Mgi Id | MGI:5644380 | Doi | 10.1002/jbmr.1835 |
| Citation | Kamiya Y, et al. (2013) Increased mandibular condylar growth in mice with estrogen receptor beta deficiency. J Bone Miner Res 28(5):1127-34 |
| abstractText | Temporomandibular joint (TMJ) disorders predominantly afflict women of childbearing age, suggesting a role for female hormones in the disease process. In long bones, estrogen acting via estrogen receptor beta (ERbeta) inhibits axial skeletal growth in female mice. However, the role of ERbeta in the mandibular condyle is largely unknown. We hypothesize that female ERbeta-deficient mice will have increased mandibular condylar growth compared to wild-type (WT) female mice. This study examined female 7-day-old, 49-day-old, and 120-day-old WT and ERbeta knockout (KO) mice. There was a significant increase in mandibular condylar cartilage thickness as a result of an increased number of cells, in the 49-day-old and 120-day-old female ERbeta KO compared with WT controls. Analysis in 49-day-old female ERbeta KO mice revealed a significant increase in collagen type X, parathyroid hormone-related protein (Pthrp), and osteoprotegerin gene expression and a significant decrease in receptor activator for nuclear factor kappa B ligand (Rankl) and Indian hedgehog (Ihh) gene expression, compared with WT controls. Subchondral bone analysis revealed a significant increase in total condylar volume and a decrease in the number of osteoclasts in the 49-day-old ERbeta KO compared with WT female mice. There was no difference in cell proliferation in condylar cartilage between the genotypes. However, there were differences in the expression of proteins that regulate the cell cycle; we found a decrease in the expression of Tieg1 and p57 in the mandibular condylar cartilage from ERbeta KO mice compared with WT mice. Taken together, our results suggest that ERbeta deficiency increases condylar growth in female mice by inhibiting the turnover of fibrocartilage. |
