The Mechanism Of Hsya On Inhibiting The IL-1β Inducing Degeneration Of Endplate Chondrocytes

Objectives and Significancesr:The fundamental pathological change of disc degenerative disease(such as cervical spondylosis) is intervertebral disc degeneration. Such diseases become recognized as a refractory disease for its prevalence increasing on young age year by year, which have a serious impact on the patients'life quality. Reducing the injury of endplate cartilage is important to prevent the intervertebral disc degeneration. Therefore, the protection of the endplate chondrocyte for the prevention and treatment of intervertebral disc degenerative disease is essential.The injection of Safflower extracts is better for the treatment of osteoarthritis, synovial inflammation and cervical spondylosis. Hydroxysafflower yellow A(HSYA) is the main active ingredient of traditional Chinese medicine with a wide range of pharmacological effects. The preliminary experimental results suggest that HSYA has the potential function to delay the course of disc degeneration. Further exploration on the protective mechanism of HSYA on endplate chondrocytes induced by inflammation which base on the preliminary work is of great significant for the development of new drugs and the expansion of the new drug indications.Methods:Establishing inflammatory degeneration model is induced by IL-1p at a concentration of10ng/ml on normal mouse cartilage endplate cells. Through cytochemical staining, immunofluorescence, and transmission electron microscopy observation, cck-8cell proliferation assay,flow cytometry analysis, Real-time RT-PCR detecting mRNA expression and western blot detecting protein expression and other experimental methods for investigating the concrete effect mechanism of HSYA.Results:IL-1β with a concentration of10ng/ml could induce inflammation degeneration of the endplate chondrocytes. HSYA at different concentrations can antagonize the inhibition of IL-1β in chondrocytes proliferation and promote chondrocytes proliferation. Besides, HSYA at a concentration of10-5mol/L is the most significant. HSYA can reduce the expression levels of Bax mRNA and Bax protein in inducd-cells, and increase the expression levels of Bcl-2mRNA and Bcl-2protein at the same time. HSYA can sustain the normal morphology of cartilage endplate cells induced by IL-1β and reduce the proportion of cell hypertrophy.HSYA can also decrease the mRNA expression level of cytokine IL-1β, TNF-a, IL-6and iNOs. HSYA not only reduce the expression level of colⅩ and MMP-1, but also increase the expression level of colⅡ, aggrecan and TIMP-1of cytoplasm in degeneration chondrocytes. Meanwhile, it can reduce the mRNA expression levels of colX, MMP-1, MMP-13and increase the mRNA expression levels of colll and aggrecan. The regulation of HSYA on TIMP-1is biphasic. HSYA reduce the mRNA expression level of TIMP-1in the early degeneration, but increase its expression in the latter phase.Conclusions:IL-1β can induce degeneration of mouse endplate chondrocytes. HSYA can antagonise the inhibition of IL-1(3in the proliferation of chondrocytes and promote its proliferation. HSYA can also antagonise the inhibition of IL-1(3which induced apoptosis of mouse intervertebral disc endplate chondrocyte and its degeneration. In conclusion, HSYA has a protective effect on endplate chondrocytes induced by IL-1β.Figure9, table4, reference91...