The function and mechanism of histone deacetylase 4 in osteoarthritis

Many factors contributes the process during the onset and development of osteoarthritis (OA), makes this process extremely complex. Histone deacetylase 4 (HDAC4) is very important to the OA pathological process because it can receive several crucial cellcularfactors’regulation and regulate many cytokines which involved in chondrocyte hypertrophy at the same time. During this process, Parathyroid hormone-related protein (PTHrP) can promote the nuclear location of HDAC4 through maintain phosphorylation of HDAC4 therefor repress runt-related transcription factor-2 (Runx-2)’s production and function at genetic and molecular level. The reduction of Runx-2 can repress the production of matrix metalloproteinase-13 (MMP-13), which on one hand decrease the digestion of type Ⅱ collagen and Aggrecan, on the other hand release the repression of SRY-related high mobility group-box gene (Sox-9). Therefore successfully increase the production of Type Ⅱ collagen. So, knowing the function and mechanism of HDAC4 in OA is important to understand it’ s pathological process. This review aims to summarize the latest progress of HDAC4 and cellcular factors involved in OA. Key words: Osteoarthritis; Histone deacetylase 4; Cytokines