Alleviation Of Hydrogen Peroxide Induced Oxidative Stress In The Rats’ Chondrocyte:Effects Of The Amniotic Mesenchymal Stem Cells Derived Exosome

Objective:To explore the role of amniotic mesenchymal stem cells derived exosome in alleviating oxidative stress in temporomandibular condylar articular cartilage cells and to provide experimental evidence for the treatment of temporomandibular arthritis by constructing the oxidative stress cell model of rat temporomandibular joint arthritis.Methods:The rat temporomandibular joint chondrocytes were isolated by trypsin and collagenase digestion.Identification of condylar chondrocyte through toluidine blue staining and collagen Ⅱ staining.The selection of suitable concentration of hydrogen peroxide through CCK8 and β-gal staining.The amniotic membrane layer was collected from the abandoned human placenta tissue,and amniotic mesenchymal stem cells were isolated and obtained.After the preliminary identification of its mesenchymal cell special markers and multi differentiation ability,the exosome derived from amniotic mesenchymal stem cells was isolated by ultracentrifugation.Under the stimulation of hydrogen peroxide,the oxidative and antioxidant indices in the condylar chondrocytes of rats in the control group and the expression level of inflammatory related factor proteins were detected.After treated with conditioned medium and exosome,the levels of oxidation and antioxidant indexes and the expression of inflammatory related factor protein were dectected in each group.Results:The experimental results showed that the cells of toluidine blue staining and type Ⅱ collagen cytochemical staining were positive,and the optimum concentration of CCK8 and beta-gal staining for hydrogen peroxide was 100 mol/L.The cultured human amniotic mesenchymal stem cells are fibroblast like cells with adherent growth.It is identified by FCM to prove that the cells are the source of mesenchymal cells and have multi differentiation ability in different induced microenvironments.The diameter of the exosome ranged from 40 to 200nm,can be internalized by cartilage cells,and does not have cytotoxicity to chondrocytes in the range of 0 to 1000 mμg/ml.After adding exosome and the conditioned medium of amniotic mesenchymal stem cells,the level of oxidative stress index,the level of inflammatory related factor protein decreased obviously,the level of antioxidant index increased obviously,and the alteration of exosome group were more significant.Conclusion:This study found that the exosome derived from amniotic mesenchymal stem cells decreased the level of oxidative stress and the level of inflammatory factor related proteins in the cartilage of the temporomandibular joint after oxidative stress whereas the capacity of antioxidation were enhanced.