Abstract

Sinomenine (SIN) is an isoquinoline derived from Caulis Sinomenii that has been used to treat rheumatoid arthritis and osteoarthritis for several decades in China. This study aims to reveal the effects of SIN on mouse chondrogenic ATDC5 cells growth and inflammation. SIN was used to treat ATDC5 cells injured by lipopolysaccharides (LPS). The following parameters were determined for evaluating the treatment effects of SIN: cell viability, apoptosis, reactive oxygen species generation, and pro‐inflammatory cytokines release. Besides, the expression of LPS‐sensitive miRNA (miR‐192) and the activation of NF‐κB and MAPK signaling were studied to explain SIN's function. SIN with concentration of 30 μM significantly attenuated LPS‐induced cell damage via increasing cell viability, inhibiting apoptosis and reactive oxygen species generation, and declining IL‐6 and TNF‐α release. miR‐192 was downregulated by SIN treatment. Restoration of miR‐192 expression by miRNA transfection could significantly impede SIN's protective action. Besides, the inhibitory effects of SIN on the activation of NF‐κB and MAPK signaling were attenuated by miR‐192 overexpression. Furthermore, GDF11 was found to be a target gene of miR‐192. LPS‐mediated injury to chondrogenic ATDC5 cells can be relieved by SIN via downregulating miR‐192 and subsequently repressing the activation of NF‐κB and MAPK signaling.