Effects of CM-chitosan on the mRNA levels of iNOS, IL-10, JAK1, STAT3 and SOCS3 in LPS-induced rat chondrocytes. Rat chondrocytes were treated with LPS and subsequently increasing concentrations (50, 100 and 200 µg/ml) of CM-chitosan were added. Reverse transcription-quantitative polymerase chain reaction was used to measure the relative mRNA levels of (A) iNOS, (B) IL-10, (C) JAK1 (D) STAT3 and (E) SOCS3. Data are presented as the mean ± standard deviation. #P<0.05 vs. the control group, *P<0.05 vs. the LPS group, **P<0.05 vs. the LPS+50 µg CM-chitosan group, and ***P<0.05 vs. the LPS+100 µg CM-chitosan group. CM, carboxymethyl; iNOS, inducible nitric oxide synthase; IL, interleukin; JAK, janus kinase; STAT, signal transducer and activator of transcription; SOCS suppressor of cytokine signaling; LPS, lipopolysaccharide.