Study On 10-gingerol Delaying The Progression Of Osteoarthritis Through Keap1-Nrf2-ARE Signal Pathway

Osteoarthritis(OA)is a joint degenerative disease with a high incidence rate.It is one of the important causes of disability and seriously affects the quality of life of patients.However,no drugs have been developed that can effectively delay the progression of OA.Oxidative stress is a negative effect produced by reactive oxygen species(ROS)in the body.Oxidative stress can stimulate inflammatory reactions and induce chondrocyte apoptosis,which plays an important role in the progress of OA.Current research shows that antioxidants can protect chondrocytes and prevent the degradation of extracellular matrix(ECM),thereby delaying the development of OA.Ginger has been proven to be a natural plant with antioxidant properties,and 10Gingerol is one of the main active components in ginger.However,the efficacy of 10Gingerol in the treatment of OA is unclear.This study explored the effect of 10-Gingerol on significantly delaying the progression of OA through in vitro and in vivo experiments,and explored the mechanism of action of 10-Gingerol,thereby revealing that 10-Gingerol may become a new drug for the treatment of OA.Chapter 1 In vitro experimental study of 10-Gingerol protecting chondrocytes and cartilage tissueObjective:To investigate whether 10-Gingerol has a protective effect on cartilage ECM,identify its core targets,clarify the specific mechanism of action of 10-Gingerol,and evaluate the therapeutic effect of 10-Gingerol on OA.Methods:Screening core targets through network pharmacology,molecular docking,and other technologies,determining the optimal concentration range of 10-gingerol through CCK-8,and evaluating the synthesis and decomposition of cartilage ECM and the expression of related signal pathways through RT-qPCR,WB,immunofluorescence staining,safranine O staining,alcian blue staining,immunohistochemical staining,and flow cytometry.Results:The enrichment analysis of intersection targets between 10-gingerol and OA mainly reflected in oxidative stress,inflammation and apoptosis Molecular docking showed that 10-Gingerol could bind to Keapl,which may be an inducer of Nrf2,and may become a potential target for the treatment of OA.CCK-8 results showed that the safe concentration range of 10-Gingerol was 0-10 μM。In phenotypic studies of OA,10-Gingerol reduced the expression of MMP13 and ADAMTS5,and promoted the expression of ACAN,COL2A1,SOX9-and PRG4.In the study of the mechanism of OA,10-Gingerol can upregulate the expression of Nrf2 in the nucleus,while upregulating the expression of HMOX1,GCLC,NQO1,GPX1,SOD2,and CAT,reducing the level of ROS in chondrocytes.10-Gingerol can also downregulate IL-6,COX2,iNOS,and TNFα,while reducing the phosphorylation modification levels of p65 and IκBα in chondrocytes,which inhibiting the inflammatory response of chondrocytes.In addition,10-Gingerol can downregulate the expression levels of BAX and Cleared Caspase3,reduce the phosphorylation modification levels of JNK and p38 MAPK,and upregulate the expression level of BCL2,which inhibiting the apoptosis of chondrocytes.However,when Nrf2 was knocked down,the protective effect of 10Gingerol on chondrocytes was reversed.Conclusion:10-Gingerol can activate the Keap1-Nrf2-ARE signaling pathway and inhibit NF-κB and JNK/p38 MAPK signaling pathways,which reducing the ROS level of chondrocytes,alleviating oxidative stress and inflammatory reactions in chondrocytes and reducing apoptosis of chondrocytes.10-Gingerol can inhibit the degradation of cartilage ECM,promote its synthesis,which delaying the progress of OA.Chapter 2 In vivo experimental study of 10-Gingerol delaying the development of osteoarthritis in ratsObjective:To evaluate the therapeutic effect of 10-Gingerol on OA in vivo by intervening the knee joints of OA rats with 10-Gingerol.Methods:A rat model of OA was established,and 10-Gingerol was injected into the knee joint cavity of the rats for 8 consecutive weeks.The hot plate test and weight bearing test were performed.The knee joint tissues of the rats were taken and stained with HE,safranine O-solid green,alcian blue,immunohistochemistry,and OARSI scores.The knee joint function and cartilage wear were evaluated.Results:The functional test results showed that 10-Gingerol could increase the reaction time to pain in OA rats,and reduce the weight bearing gap in both hind limbs of OA rats.Histological evaluation and OARSI score indicate that 10-Gingerol can promote the synthesis of cartilage proteoglycans,glycosaminoglycans,and type Ⅱ collagen fibers,reducing cartilage loss and destruction.Conclusion:10-Gingerol-can improve the pain tolerance of the knee joint and the weight bearing ability of the hind limbs in OA rats,while preventing the loss and destruction of ECM in the knee cartilage of rats,and delaying the progress of OA.