| Objective:To observe the key inflammation cytokines and their expression aftercarotid artery stenting,to distinguish the high expression and duration ofMMP-9and other inflammation cytokines, for providing experimentalbasis for drug intervention. To investigate effect of injured endothelial cellsupernatant on THP-1monocytes, and establish a simple vitro model ofmechanical injury in carotid artery stenting. Observe the mechanism duringTHP-1monocytes was induced by injured endothelial cell supernatant andMatrix metalloproteinase-9(MMP-9) expression. To explore weathertelmisartan involved in the mechanism, and clinical prospect of patientswith carotid artery stenting.Methods:Part one: A following up survey was carried up in the patients withcarotid artery stenting before and at24hours,3months and6months afteroperation, including baseline characteristics, medications andcomplications. ELISA was applied to measure the expression of interleukin-1β (IL-1β), interleukin-6(IL-6), Transforming frowth factor-β(TGF-β) and MMP-9in serum. Toll like receptor-4(TLR-4) expression ofperipheral blood monocytes were detected by flow cytometry.Part two: THP-1cells treated with normal endothelial cell supernatantas negative control group, to test the adhesion ability of THP-1exposed tothe supernatant of endothelial cells injury to a different extent.Transwellwas used to evaluate the changes of migration and invasion of THP-1monocytes in each group treated with injured or uninjured endothelial cellsupernatant. Immunofluorescence was applied to analysis the time andlocation of phosphorylation-extracellular regulated kinase1/2(P-ERK1/2)expression.Part three: THP-1cells were treated with normal endothelial cellsupernatant as negative control group. With the use of Western blot, timecourse of P-ERK1/2, phosphorylation-ETS-like1(P-ELK-1), MMP-9expression were determined. MTT was used for screening Optimumconcentration of telmisartan. P-ERK1/,P-ELK-1,MMP-9expression is alsomeasured under circumstance of adding PD98059(ERK1/2inhibitor)andTelmisartan.Results:Part one:74patients were included in the study,48males and26females, the average age of them is66.15±7.39years. In the following halfof the year after stenting, one patient with transient ischemic attack (TIA), two with stroke, one death, three with hemorrhagic tendency,and norestenosis was found. Inflammation cytokines of IL-1β, IL-6, TGF-β,MMP-9obviously elevated at24hours after stenting(P＜0.05). IL-1β,IL-6,TGF-β returned to the preoperative levels3months after operation(P>0.05), but high expression of MMP-9continued for3months afterstenting(P＜0.05). TLR-4had little changes before and after carotidstenting (P>0.05) and the following3months (P>0.05), TLR-4had beenfound no significant difference before and after stenting (P>0.05).Part two: Injured endothelial cell supernatant enhanced cell adhesion,migration and invasion of THP-1monocytes(P＜0.05). P-ERK1/2translocated from cytoplasma into nuclei.Part three: Injured endothelial cell supernatant induced P-ERK1/2,P-ELK-1and MMP-9expression in THP-1cell, and P-ERK1/2reach to thepeak at15min, P-ELK-1at15min and MMP-9at6hours(P＜0.05).PD98059can reduce P-ELK-1expression and so dose MMP-9(P＜0.05).Optimum concentration of telmisartan is10μ mol/L. It suppressedexpression of MMP-9via inhibition of ELK-1(P＜0.05).Conclusions:1. expression of IL-1β,IL-6,TGF-β,MMP-9were elevated aftercarotid artery stenting,high expression of MMP-9may related tothe vascular stenosis.2. It is uclear weather the TLR-4take part in the inflammation and restenosis prosess after stening, more reaserchs are needed.3. Supernatant of mechanic injured endothelial cells can effectivelyactivate THP-1monocytes.4. ERK1/2regulated MMP-9expression of THP-1cell induced bymechanic injury of endothelial cell supernatant through ELK-1.5. Telmisartan can effectively inhibit ELK-1expression to decreasethe expression of MMP-9.
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