Blocking circadian clock factor Rev-erbα inhibits growth plate chondrogenesis via up-regulating MAPK-ERK1/2 pathway

Emerging evidence indicated circadian clock gene Rev-erbα was involved in cartilage metabolism, however the contribution of Rev-erbα to growth plate chondrogenesis remains unknown. Here, we found that Rev-erbα exhibited the spatiotemporal expression model in growth plate. Moreover, Rev-erbα antagonist SR8278 inhibited longitudinal elongation of metatarsal bone ex vivo. And morphological analysis exhibited SR8278 led to the reduced height of growth plate and hypertrophic zone. Furthermore, blocking Rev-erbα suppressed the proliferation and hypertrophic differentiation of chondrocytes in growth plate. Similarly, knock-down Rev-erbα inhibited the proliferation and differentiation of primary chondrocytes in vitro. The mechanistic study indicated that knock-down Rev-erbα up-regulated MAPK-ERK1/2 pathway in chondrocytes. However, restraint of MAPK-ERK1/2 pathway alleviated partially SR8278-inhibited longitudinal elongation of metatarsal bone and growth plate development. Therefore, our results provide evidence of the vital role of Rev-erbα on growth plate chondrogenesis.