The Protective Effect And Mechanism Of Simvastatin Nanoparticles On CLP And Mice A549 Cells

Background:Sepsis is a critical disease that threaten human health and life, and aslo one of the important direction of intensive medical research.After decades of basic research and clinical trials, there is still no fundamental gold standard of treatment.Closer to its diversity of statins, is widely used in the study of the treatment of sepsis. Studies showed that statins may be protected through anti-inflammation and improve blood vessel function and other therapeutic effect on sepsis.But in clinical and basic research, has been for the curative effect of statins and clinical application value.Through the cells and zoological research, We explore simvastatin for protection of sepsis and its mechanism, and the treatment of sepsis possible targets.Objective:This research mainly explores the protective effects and the possible molecular mechanisms of simvastatin on CLP mice and A549 cells. And the improvement of the drug dosage form, nanoparticles,is aslo our goal.Methods:The sepsis cell model of A549 and THP-1 were induced by LPS,and the A549 cells were aslo coculture with THP-1 to simulating sepsis cell model.When the model setted,cells were theated with simvastatin nanoparticles and common vein dosage form.The scratch test detect A549 cell migration ability both in coculture model and alone culture.Using Western blot to detecting the changes of the expression of iNOS and eNOS in A549 and THP-1. The content of TNFαand IL-6 in THP-1 and A549 cell medium were detect by ELISA method.The mice sepsis models was established by CLP method, and the control group was established by the shame method.The mice were given simvastatin by lavage,the common preparation tail vein, nanoparticle preparation tail intravenous injection.The effect of simvastatin to sepsis in mice and the efficacy of different preparations were studied.The lung and the abdomen aorta were collected 24 hours after the treating.The tissues were by HE staining and immunohistochemistry stain, then to investigating the effect of simvastatin on CLP mice pathological changes and regulation of iNOS/eNOS.Results:1) LPS and LPS pretreatment THP-1 medium can promote A549 cell migration, simvastatin inhibiting A549 cell migration.LPS can increase the secretion of IL-6 and TNF-αin THP-1 cells, also can promote the production of IL-6 in A549 cells. Simvastatin decreased the IL-6 and TNF-ainflammatory factor obviously.2) The mice mortality increased significantly in the CLP group, simvastatin reduced mortality. simvastatin can obviously improve the mice lung pathological outcomes. INOS express high in CLP mice lungs and abdominal aorta, and the eNOS expression is suppressed.ENOS expressed in simvastatin group increased.Mice aorta immunohistochemical results suggest that CLP increase the Cav and iNOS expression, and the expressions of PI3K, and AKT, eNOS increased in simvastatin group.3) Each group simvastatin preparations:nanoparticles group curative effect best, worst oral group.Conclusions:1) Simvastatin can inhibit the IL-6, TNF-a release from THP-1,and IL-6 from A549.2) Simvastatin can inhibit A549 cell migration to maintaining the normal function of the alveolar epithelium.3) Simvastatin can directly reduce the mortality of sepsis mice, and can significantly improve sepsis mice lung lesions.Simvastatin has a protective effect in sepsis mice.4) The result of cell western blot and mice immunohistochemical show that simvastatin can inhibit the expression of iNOS directly, and inhibit the negative regulating protein Caveolin expression,and activating the PI3K/AKT pathway to promote the expression of eNOS.It is important to maintain the balance of iNOS/eNOS in mice in sepsis.5) Nanoparticles as a new type of medicine preparations. The effect is superior to other agents in some of our experiment.