CB2-mediated attenuation of nucleus pulposus degeneration via the amelioration of inflammation and oxidative stress in vivo and in vitro

Abstract

Background Nucleus pulposus cell (NPC) degeneration is widely accepted as one of the major causes of intervertebral disc (IVD) degeneration (IVDD). The pathogenesis of IVDD is complex and consists of inflammation, oxidative stress, and the loss of extracellular matrix (ECM). Cannabinoid type 2 receptor (CB2) has been shown to be involved in the pathological mechanism of a variety of diseases due to its anti-inflammatory effects and antioxidative stress capacity. Method In Vitro, H2O2 was used to induce degeneration of nucleus pulposus cells, mRNA and protein expression level was determined by RT-PCR and Western Blot, and Immunocytochemical staining were used to detect expression of collagen II, aggrecan, MMP3/13, superoxide dismutase 2 (SOD2) and inducible nitric oxide synthase (iNOS). In vivo, the potential therapeutic effect of CB2 was detected in the rat acupuncture model. Result In vitro, we found that the CB2 agonist (JWH133) treatment reduced the oxidative stress level in NPCs induced by hydrogen peroxide (H2O2) treatment. Furthermore, the expression of inflammatory cytokines was also decreased by JWH133 treatment. We found that collagen II and aggrecan expression was preserved, whereas matrix metalloproteinase levels were reduced. In vivo, we established a rat model by needle puncture. Imaging assessment revealed that the disc height index (DHI) and morphology of IVD were significantly improved, and the disc degeneration process was delayed by treatment of JWH133. Furthermore, immunohistochemical (IHC) staining revealed that JWH133 could inhibit the degradation of collagen II and decrease the expression of MMP3. Conclusions The experiment indicates the oxidative stress and inflammatory response of rat NPCs induced by H2O2 could be inhibited by activating CB2. This study reveals that CB2 activation can effectively delay the development of IVDD, providing an effective therapeutic target for IVDD.

Scientific literature landscape analysis of researches on oxidative stress in intervertebral disc degeneration in web of science

“…The top ten high-yield research directions were presented in Table 3 . Cell Biology occupied the most records ( n = 111), the highest H-index of 26, the highest total citations ( n = 2091) and average citations ( n = 18.84) ( Cheng et al, 2021 ). Rheumatology occupied the most average citations ( n = 43.40).…”

Scutellarin Protects Against Mitochondrial Reactive Oxygen Species-Dependent NLRP3 Inflammasome Activation to Attenuate Intervertebral Disc Degeneration

“…The needle puncture rat IVDD model is widely used for investigating IVD degeneration in vivo ( Cheng et al, 2021 ; Wu et al, 2021 ). The degenerative phenotype of IVD is displayed in this model, including alteration of disc signal in MRI, a decrease of disc height through X-ray, and loss of ECM component as well as disorganized expression of metabolic markers through histological analysis ( Zhao et al, 2020 ).…”

Optineurin-mediated mitophagy as a potential therapeutic target for intervertebral disc degeneration

“…To study OPTN expression levels in NPCs during oxidative stress, H 2 O 2 was used to induce cellular oxidative damage ( Lin et al, 2021a ; Cheng et al, 2021 ). NPCs were exposed to different concentrations of H 2 O 2 (0, 200, 400, 500, 600, 800 μM) for 2 h. The optimal conditions for inducing cellular senescence were determined by treating NPCs with the same concentration of H 2 O 2 (400 μM) for different times (0, 0.5,1, 2, 4, 6 h).…”