Scutellarin suppresses cartilage destruction in osteoarthritis mouse model by inhibiting the NF-κB and PI3K/AKT signaling pathways.

Osteoarthritis (OA), a common and severe disease, is predominantly characterized by cartilage destruction, which results in the degeneration of joint surfaces. Nowadays, it is accepted that TNFα plays a critical role in OA. Scutellarin, the main bioactive flavonoid glycoside extracted form Erigeron breviscapus, has been reported to exert positive effects on anti-inflammatory reactions. However, the effect of scutellarin in OA is still unknown. In this study, we isolated and cultured primary murine chondrocytes, stimulating TNF-α, in the presence or absence of scutellarin treatment. We found that the inflammatory response stimulated by TNF-α was significantly inhibited by the addition of scutellarin. Moreover, we established OA mouse models induced by surgery. In this mouse model, both inflammatory reaction and cartilage degeneration were markedly inhibited by oral administration of scutellarin. Furthermore, the cellular mechanism underlying the protective effect of scutellarin in OA was clearly associated with the NF-κB and PI3K/AKT signaling pathways. Collectively, this study proposes scutellarin as a potential therapeutic to treat joint degenerative diseases, including OA.

Wang W ，Li J ，Li F ，Peng J ，Xu M ，Shangguan Y ，Li Y ，Zhao Y ，Qiu C ，Qu R ，Li W ，Zhang C ，Zhang T ... -  《-》

Scutellarin ameliorates cartilage degeneration in osteoarthritis by inhibiting the Wnt/β-catenin and MAPK signaling pathways.

Osteoarthritis (OA) is a chronic inflammatory disease that is the basis of cartilage extracellular matrix degeneration and joint inflammation. Scutellarin is an herbal flavonoid glucuronide, isolated from the Chinese traditional herb Erigeron breviscapus, has been reported to have anti-inflammatory effect. Here, we showed that Scutellarin could inhibit inflammation and protects cartilage from degeneration in vitro and in vivo. Scutellarin downregulate the mRNA and protein expression of MMP1, MMP13, and ADAMTS-5, Wnt3a, Frizzled7 and promote the expression of Collagen II and Aggrecan. Moreover, scutellarin inhibit the migration of β-catenin and phosphorylation of p38 into the nucleus, which may relate to the mediation of the Wnt/β-catenin and MAPK signaling pathway. Furthermore, scutellarin significantly inhibit the cartilage degradation of DMM-induced OA mice by safranin-O and fast green staining. In conclusion, our study indicates that scutellarin may be a potential drug for the treatment of OA.

Liu F ，Li L ，Lu W ，Ding Z ，Huang W ，Li YT ，Cheng C ，Shan WS ，Xu J ，He W ，Zhanghui ，Yin Z ... -  《-》

Scutellarin regulates osteoarthritis in vitro by inhibiting the PI3K/AKT/mTOR signaling pathway.

Ju SH ，Tan LR ，Liu PW ，Tan YL ，Zhang YT ，Li XH ，Wang MJ ，He BX ... -  《-》

Scutellarin ameliorates osteoarthritis by protecting chondrocytes and subchondral bone microstructure by inactivating NF-κB/MAPK signal transduction.

Osteoarthritis (OA), a chronic degenerative disease, is a major cause of pain, disability, and reduced quality of life among the elderly worldwide. The key to treating it is early prevention and effective intervention. The anti-inflammatory effects of scutellarin (SCU), a flavonoid derived from Erigeron breviscapus, have been increasingly reported. However, the mechanism by which SCU affects OA remains unclear. This study aimed to investigate the therapeutic effects and potential molecular mechanisms of SCU in the development of OA. Here, we found that SCU inhibited interleukin (IL)- 1β-induced degradation of the extracellular matrix (ECM) of cartilage through the NF-kappaB/mitogen-activated protein kinases (NF-κB/MAPK) signaling pathway. In addition, in vivo data showed that SCU significantly reduced cartilage damage in the destabilization of the medial meniscus (DMM) mouse model and ovariectomy (OVX)-induced subchondral bone loss and cartilage degeneration in mice. In summary, our data showed that SCU is expected to become a potentially effective candidate treatment strategy for OA.

Yang H ，Wang Z ，Wang L ，Li Y ，Guo J ，Yang X ，Zhao J ，Rong K ，Zhang P ，Ye B ，Zhang K ，Ma H ... -  《-》

Sinomenine contributes to the inhibition of the inflammatory response and the improvement of osteoarthritis in mouse-cartilage cells by acting on the Nrf2/HO-1 and NF-κB signaling pathways.

Pathological changes, such as articular cartilage degeneration, destruction, and hyperosteogeny, are regarded as the main features of osteoarthritis (OA). Sinomenine (SIN) is a monomeric component purified from the plant Sinomenium acutum which has been found to have anti-inflammatory effects, however, the mechanism of action of SIN on OA is not clear. In this study, we evaluated whether SIN could regulate the inflammatory response induced by interleukin (IL)-1β and improve outcomes in the instability model of OA (medial meniscus mice (DMM)) by acting on the Nrf2/HO-1 and NF-κ B signaling pathways in chondrocytes. From our experiments, which include Griess reaction, ELISA, Western blot, and immunofluorescence, we found that SIN not only down-regulated the expression of pro-inflammatory factors induced by IL-1β, including; inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), nitricoxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), but also decreased the production of IL-1β-induced cartilage matrix catabolic enzymes including; ADAMTS-5 and MMPs, in mouse chondrocytes. In addition, the degradation of aggrecan and type II collagen protein in the extracellular matrix (ECM) stimulated by IL-1β was reversed. Most importantly, we have revealed for the first time that in OA, SIN inhibited the inflammatory response and ECM degradation by activating the Nrf2/HO-1 signaling pathways and inhibiting NF-κB activity in mouse-cartilage cells. In in vivo experiments, SIN treatment helped to improve the cartilage destruction in OA model mice. In conclusion, this study has demonstrated that SIN inhibits the IL-1β-induced inflammatory response and cartilage destruction by activating the Nrf2/HO-1 signaling pathway and inhibiting the NF-κB signaling pathway in mouse chondrocytes, suggesting a new use for SIN in the treatment of OA.

Wu Y ，Lin Z ，Yan Z ，Wang Z ，Fu X ，Yu K ... -  《-》