Wang, Yuji

Abstract Background Osteoarthritis (OA) is one of the most common degenerative diseases. Accumulating evidence suggests that ferroptosis may be important in the progression of OA. Angelica Sinensis polysaccharide (ASP), a traditional Chinese medicine, possesses antioxidative, anti-inflammatory and anti-apoptotic properties. However, it is unclear whether ASP can slow down the progression of osteoarthritis by suppressing ferroptosis. Methods Collection of postoperative joint cartilage from patients who underwent total knee arthroplasty (TKA), detection of ferroptosis-related markers including glutathione peroxidase 4 (GPX4) and ferritin heavy polypeptide 1 (FTH1) expression, as well as glutathione (GSH) and malondialdehyde (MDA) levels, and investigation of the correlation between ferroptosis and osteoarthritis. Chondrocytes were isolated and cultured, stimulated separately with IL-1β or erastin, rescued by ASP and ferroptosis inhibitors, and changes in cell viability and ferroptosis were detected. A destabilization of the medial meniscus surgical model (DMM) model was established in mice, and ASP was administered orally at different dosages to evaluate its therapeutic effect and level of ferroptosis. Results First, the expression of GPX4, FTH1 and reduced GSH was lower while the MDA level was up-regulated in cartilage of the OA group as compared to the control group. Moreover, chondrocyte ferroptosis induced by Erastin or IL-1β was rescued by the application of ASP or ferroptosis inhibitors in vitro. Further, the anti-ferroptotic effect of ASP was related to enhanced nuclear transfer of Nrf2 and decreased activation of NF-κB as indicated by down-regulated expression of p-p65. Next, the in vivo experiments showed that ASP alleviated the cartilage damage of mice joints induced by DMM. Conclusions In summary, ASP can attenuate chondrocyte ferroptosis through the Nrf2/NF-κB pathway in the progression of OA, suggesting that ASP may a potential inhibitor of ferroptosis for the treatment of OA.

Abstract ObjectiveChondrocyte apoptosis plays a vital role in osteoarthritis (OA) progression. Angelica sinensis polysaccharide (ASP), a traditional chinese medicine, possesses anti-inflammatory and anti-apoptotic properties in chondrocytes. This study aimed to determine the protective role of ASP on sodium nitroprusside (SNP)-induced chondrocyte apoptosis, and explore the underlying mechanism.MethodHuman primary chondrocytes isolated from articular cartilage of OA patients were treated with SNP alone or in combination with different doses of ASP. Cell viability and apoptosis were assessed, and apoptosis-related proteins including Bcl-2 and Bax were detected. Autophagy levels were evaluated by light chain 3 (LC3)II immunofluorescence staining, mRFP-GFP-LC3 fluorescence localisation and western blot (LC3II, p62, Beclin-1, Atg5). Meanwhile, activation of ERK 1/2 pathway was determined by western blot. The autophagy inhibitors, 3-Methyladenine (3-MA), chloroquine (CQ) and a specific inhibitor of ERK1/2, SCH772984, were used respectively to confirm the autophagic effect of ASP.ResultsThe results showed that SNP-induced chondrocyte apoptosis was significantly rescued by ASP, whereas ASP alone promoted chondrocytes proliferation. The anti-apoptotic effect of ASP was related to the enhanced autophagy and depended on the activation of ERK1/2 pathway.ConclusionASP markedly rescued SNP-induced apoptosis by activating ERK1/2-dependent autophagy in chondrocytes, and it made ASP a potential therapeutic supplementation for OA treatment.

Abstract ObjectiveChondrocyte apoptosis plays a vital role in osteoarthritis (OA) progression. Angelica sinensis polysaccharide (ASP), a traditional Chinese medicine, possesses anti-inflammatory and anti-apoptotic properties in chondrocytes. This study aimed to determine the protective role of ASP on sodium nitroprusside (SNP)-induced chondrocyte apoptosis, and explore the underlying mechanism.MethodHuman primary chondrocytes isolated from articular cartilage of OA patients were treated with SNP alone or in combination with different doses of ASP. Cell viability and apoptosis were assessed, and apoptosis-related proteins including Bcl-2 and Bax were detected. Autophagy levels were evaluated by light chain 3 (LC3)-II immunofluorescence staining, mRFP-GFP-LC3 fluorescence localisation and western blot (LC3II, p62, Beclin-1, Atg5). Meanwhile，activation of ERK 1/2 pathway was determined by western blot. The autophagy inhibitors 3-Methyladenine (3-MA), chloroquine (CQ) and a specific inhibitor of ERK1/2, SCH772984, were used respectively to confirm the autophagic effect of ASP.ResultsThe results showed that SNP-induced chondrocyte apoptosis was significantly rescued by ASP, whereas ASP alone promoted chondrocytes proliferation. The anti-apoptotic effect of ASP was related to the enhanced autophagy and depended on the activation of ERK1/2 pathway.ConclusionASP markedly rescued SNP-induced chondrocyte apoptosis by activating ERK1/2-dependent autophagy in chondrocytes, and it made ASP a potential therapeutic supplementation for OA treatment.

Abstract Objective Chondrocyte apoptosis plays a vital role in osteoarthritis (OA) progression. Angelica sinensis polysaccharide (ASP), a traditional Chinese medicine, possesses anti-inflammatory and anti-apoptotic properties in chondrocytes. This study aimed to determine the protective role of ASP on sodium nitroprusside (SNP)-induced chondrocyte apoptosis, and explore the underlying mechanism. Method Human primary chondrocytes isolated from articular cartilage of OA patients were treated with SNP alone or in combination with different dose of ASP. Cell viability and apoptosis were assessed, and apoptosis-related proteins including Bcl-2 and Bax were detected. Autophagy levels were evaluated by light chain 3 (LC3)-II immunofluorescence staining, mRFP-GFP-LC3 fluorescence localisation and western blot (LC3II, p62, Beclin-1, Atg5). Meanwhile,activation of ERK 1/2 pathway was determined by western blot. The autophagy inhibitors 3-Methyladenine (3-MA), chloroquine (CQ) and a specific inhibitor of ERK1/2, SCH772984, were used respectively to confirm the autophagic effect of ASP. Results The results showed that SNP-induced chondrocyte apoptosis was significantly rescued by ASP, whereas ASP alone promoted chondrocytes proliferation. The anti-apoptotic effect of ASP was related to the enhanced autophagy and depended on the activation of ERK1/2 pathway.Conclusion ASP markedly rescued SNP-induced chondrocyte apoptosis by activating ERK1/2-dependent autophagy in chondrocytes, and it made ASP a potential therapeutic supplementation for OA treatment.

Elevated levels of follistatin‐like protein 1 (FSTL1) have been found both in mouse models for human rheumatoid arthritis (RA) and collagen‐induced arthritis (CIA). In this study, we elucidated the potential mechanisms by which FSTL1 contributes to the pathogenesis of RA. Fibroblast‐like synoviocytes (FLSs) were established from synovial tissues of RA patients and stimulated with human recombinant FSTL1. Protein and mRNA expression levels of select matrix metalloproteinases (i.e., MMP1, MMP3, MMP13) in FLS were measured by, respectively, real‐time RT‐qPCR and ELISA. Activation of MAPK and other pathways that affect MMPs were evaluated by Western blotting. We also compared concentrations of MMPs in plasma in RA patients versus healthy controls (HC). Expression levels of MMP1, MMP3, and MMP13 were clearly stimulated by FSTL1 in vitro. FSTL1 activated the inflammation‐related NF‐κB signaling pathway, as well as all three mitogen‐activated protein kinase (MAPK) pathways and the JAK/STAT3 pathway. Moreover, select chemical inhibitors that target p38 (SB203580), Erk1/2 (SP600125), JNK (SCH772984), STAT3 (AG490), and NF‐κB (BAY 11–7082) significantly attenuated MMP expression. Inhibition of Toll‐like receptor 4 by compound TAK‐242 significantly abolished those effects of FSTL1. Importantly, elevated plasma concentrations of MMP3 were found to correlate with plasma FSTL1 levels in RA patients. These findings suggest that FSTL1 accelerates RA progression by activating MAPK, JAK/STAT3, and NF‐κB pathways to enhance secretion of different MMPs and this enhancement is via TLR4. Targeting FSTL1 may provide a promising pharmacological drug therapy to ameliorate RA symptoms and perhaps reverse disease progression.