Protection on NP cells against the CM-induced inflammation and imbalanced ECM homeostasis by the treatment of MLT. NP cells were treated with different CMs collected from the LPS-stimulated RAW 264.7 Mφs in the presence or absence of MLT for 24 h, then followed by different analysis. (A) The relative mRNA levels of pro-inflammation cytokines in NP cells were measured by RT-qPCR analyses (n = 3). The levels of IL-6, TNF-α, iNOS and COX-2 mRNA declined in the presence of MLT treatment to Mφs at different dosages. (B) The relative mRNA levels of matrix anabolic and degrading enzymes in NP cells were measured by RT-qPCR analyses (n = 3). The levels of COL2A1 and TIMP-1 mRNA were upregulated, while the levels of MMP-13, ADAMTS4 and ADAMTS5 mRNA were downregulated in the presence of MLT treatment to Mφs at different dosages. (C,D) The relative protein levels of pro-inflammation cytokines in NP cells were measured by Western blot analyses (n = 3). (C) Western blotting showed the decline of inflammation-associated proteins. (D) Quantitative analysis showed the reduced levels of IL-6, TNF-α, iNOS and COX-2 protein after treatment with MLT to Mφs at different dosages. (E,F) The relative protein levels of matrix anabolic and degrading enzymes in NP cells were measured by Western blot analyses (n = 3). (E) Western blotting showed the different changes of ECM protein productions in NP cells. (F) Quantitative analysis showed the increased levels of COL2A1 and TIMP-1 protein, and the reduced levels of MMP-13, ADAMTS4 and ADAMTS5 protein after the treatment with MLT to Mφs at different dosages. Data are expressed as mean ± standard deviation. The two groups among the five groups are compared by using an independent t-test. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001.