Glucocorticoids Inducing Vascular Repair Disorders under Hypoxia via Inhibiting Cell Migration and Autocrine/paracrine:Bioinformatical Analysis Combined with Cytological Experiment

MA Jun; YANG Pei; WANG Kun-zheng

摘要：The exact molecular and cytological mechanism of how glucocorticoids induce vascular repair disorders in glucocorticoid-induced avascular necrosis of the femoral head is still unclear.We used bioinformatical tools for data mining and detected the biological behavior of endothelial cells(Ecs)under hypoxia conditions and high dose dexamethasone to reveal the mechanisms above.Six differential expression miRNAs(DE-miRNAs)were filtered from Gene Expression Omnibus(GEO)database GSE60093 which contained Ecs treated with high dose glucocorticoid and control samples.Enrichment and PPI network analyses of the DE-miRNAs target genes showed the most remarkable pathway was HIF-1 signaling pathway and high dose glucocorticoid as a negative regulator of cell differentiation,energy metabolism,migration and cytokines secretion.Glucocorticoids also reduced the activity of autocrine/paracrine via limiting ion channels and transmembrane transporter process.In cytological experiment,HUVECs were divided into four groups:hypoxia group(H),hypoxia+dexamethasone group(HD),dexamethasone group(D),the normal group(N).Cell activity detection and Live/Dead dyeing showed cell activity and the number of live cells in Group H was higher than the other three groups at 24 h after intervention,while cell activity,number and proportion of live cells in HD group were worst.Cytoskeleton staining showed HD group met cytoskeleton form disorders.The scratch assay showed cell migration ability of Group H was strongest while cell migration ability of the HD group was worst.MIF expression in HD group showed a trend of bimodal,the peak of VEGF-A secretion lagged behind the MIF's.Expression of MIF and VEGF-A in the HD group were low.High dose dexamethasone suppressed the active response of Ecs to hypoxia stimulation via directly inhibiting the expression of MIF and interdicting autocrine/paracrine mechanism.We infered that the treatment with high dose glucocorticoid would inhibit neo-angiogenesis under hypoxia followed by aggravating hypoxia/ischemia and osteonecrosis.