Effect Of The Recombinant Human Erythropoietin On Mmp9 Expression In Astrocyte After Hypoxia Culture

Objective: To investigation the effect of recombinant human erythropoietin preconditioning on the injury of astrocytes and expression of MMP-9 after hypoxia.Method: Rat cerebral cortical astrocytes from 2 days newbron SD rat were undergone the pure culture and the astrocytes were divided into control group, hypoxia group and rhEPO preconditioning group. The survival rate of astrocytes on 12h, 24h and 36h were determined by MTT assay. Inverted microscope and transmission electron microscope were used to observe the cells changes. The expression of MMP9 mRNA and protein of astrocytes were detected by immunofluorescence and RT-PCR.Reasult:he astrocytes were swelled after hypoxia cultured 12h, maximal cell swelling was observed at 36h. The rhEPO preconditioning lightened the cell swelling remarkably.Ultrastructural alterations of astrocytes such as mitochondrial swelling after hypoxia were also alleviated remarkably by rhEPO preconditioning.The results of MTT assay showed that the survival rate of rhEPO preconditioning group were obviously higher than that of the hypoxia group (P<0.05).RT-PCR and immunocytochemistry analysis confirmed that the expression of MMP9 mRNA and protein was remarkably increased at 12h, peaked at 24h and declined at 36h after hypoxia cultured.Compared with hypoxia group ,the expression of MMP9 mRNA and protein in the rhEPO preconditioning group was significantly lower at 12h, 24h and 36h (P<0.05).Conclusion: rhEPO can improve the survival rate of astrocytes under hypoxia by inhibition MMP-9.