Baicalein Inhibits the IL-1β-Induced Inflammatory Response in Nucleus Pulposus Cells and Attenuates Disc Degeneration In vivo


Intervertebral disc degeneration (IDD) is widely considered one of the main causes of low back pain, which is a chronic progressive disease closely related to inflammation and degeneration of nucleus pulposus (NP) cells. Baicalein is a natural bioactive compound with anti-inflammatory effects in different diseases, including inhibition of the inflammatory response in chondrocytes, whose morphology and avascular supply are similar to those of NP cells. Therefore, we hypothesized that baicalein may have a therapeutic effect on IDD by suppressing the inflammatory response. In vitro, NP cells were pretreated with baicalein for 2 h and then incubated with IL-1β for 24 h. We found that baicalein not only inhibited the overexpression of inflammatory cytokine production, including NO, PGE2, TNF-α, and IL-6, but also suppressed the expression of COX-2 and iNOS. The IL-1β-induced overexpression of MMP13 and ADAMTS5 and degradation of aggrecan and type II collagen were reversed by baicalein in a dose-dependent manner. Mechanistically, we found that baicalein suppressed the IL-1β-induced activation of the NF-κB and MAPK pathways. Moreover, an in vivo study demonstrated that baicalein treatment could ameliorate IDD in a puncture-induced rat model. Thus, baicalein has great value as a potential therapeutic agent for IDD.

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This work was supported by the National Natural Science Foundation of China (81871806 and 81501933), the Zhejiang Public Service Technology Research Program/Social Development (LGF18H060008), the Major Scientific and Technological Project of the Medical and Health Ministry of Zhejiang Province (WKJ-ZJ-1527), the Wenzhou Science and Technology Project (Y20170080), and the Zhejiang Provincial Natural Science Foundation of China (LY17H060008).

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Correspondence to Aimin Wu or Xiangyang Wang.

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The study was performed in accordance with the Declaration of Helsinki and relevant policies in China.

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This study was approved by the Committee of Wenzhou Medical University, and all surgical interventions, treatments, and postoperative animal care procedures were performed in accordance with the NIH Guide for the Care and Use of Laboratory Animals.

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Jin, H., Wang, Q., Wu, J. et al. Baicalein Inhibits the IL-1β-Induced Inflammatory Response in Nucleus Pulposus Cells and Attenuates Disc Degeneration In vivo. Inflammation 42, 1032–1044 (2019).

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  • intervertebral disc degeneration
  • baicalein
  • inflammation
  • NF-κB
  • MAPK