Limonin Inhibits IL-1β-Induced Inflammation and Catabolism in Chondrocytes and Ameliorates Osteoarthritis by Activating Nrf2

Figure 7

The protective effects of limonin in IL-1β-activated chondrocytes were reversed by Nrf2-siRNA and HO-1-siRNA. After Nrf2 was knocked down. (a–d) The protein expression of Nrf2, HO-1, and p65 was evaluated by western blot assay. (e–g) The protein expression of ADAMTS5 and MMP13 was evaluated by western blot assay. (h–k) After HO-1 was knocked down, the protein expression of HO-1, MMP13, and ADAMTS5 was evaluated by western blot assay. (l–o) The synthesis of NO, PGE2, TNF-α, and IL-6 in chondrocytes was evaluated by Griess reaction or ELISA. All results are represented as the . Significant differences among various groups are represented as , ; .

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