Osteoarthritis is associated with the irreversible degeneration of articular cartilage. Notably, in this condition, articular cartilage chondrocytes undergo phenotypic and gene expression changes that are reminiscent of their end-stage differentiation in the growth plate during skeletal development. Hedgehog (Hh) signaling regulates normal chondrocyte growth and differentiation; however, the role of Hh signaling in chondrocytes in osteoarthritis is unknown. Here I examined human osteoarthritic samples and mice in which osteoarthritis was surgically induced and find that Hh signaling is activated in osteoarthritis. Using several genetically modified mice, I found that higher levels of Hh signaling in chondrocytes cause a more severe osteoarthritic phenotype. Furthermore, Ishow in mice and in human cartilage explants that pharmacological or genetic inhibition of Hh signaling reduces the severity of osteoarthritis and that runtrelated transcription factor-2 (Runx2) potentially mediates this process by regulating a disintegrin and metalloproteinase with thrombospondin type 1 motif-5 (Adamts5) expression. Together, these findings raise the possibility that Hh blockade can be used as a therapeutic approach to inhibit articular cartilage degeneration.iii ACKNOWLEDGEMENTS
The WHtR further specifies cardiometabolic risk within classifications stratification on the basis of BMI percentile. A significant proportion of obese children with increased WHtRs have abnormal cardiometabolic risk factor levels. The WHtR should be included in the routine screening and assessment of overweight and obese children, and those with an elevated WHtR should undergo a further cardiometabolic risk assessment.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.