Ginkgolide B Inhibit The Molecular Mechanisms Of Human Umbilical Vein Endothelial Cells In Inflammatory Injury Induced By Ox-ldl

This study consists of two parts: literature summarization and experimental study, which will set a strong foundation for further clinical application.Literature summarization1. Literature research of GBGinkgo leaf is the dried leaf of Ginkgo biloba L and has been used in clinic for about five thousand years. It was firstly recorded in Bencao Pinhui Jingyao which said:"GB belongs to the lung channel and can astringe the lungs to treat cough and asthma. It can also tonify the heart and relieve pain". By reviewing literature from the past dynasties, we summarized GB's flavour, channel entered, distribution and action which offer the theoretical basis for the research.2. The chemistry and pharmacology research of GBGinkgo leaf contains many chemical compounds: 24% flavonoid glycosides and 6% terpenes. Flavanoid mainly removes free radicals and anti-lipid peroxidation. Meanwhile, terpenoid is an effective receptor antagonist of PAF and can suppress the platelet aggregation and prevent coagulation. GB is the most effective among all terpenes and is widely used in clinic.3. Research about ASThe mechanism and onset of AS was clearly reviewed with molecular biology in order to identify several main elements in the signal transduction passageway which were chosen as the experimental focus.4. Traditional Chinese Medicine research regarding ASThe syndrome, pathogenesis and therapeutical principle will be treated based on differentiation of syndrome, meanwhile the recent medication used for treating AS will be summarized.Experimental Studies1. The protective effect of GB against oxidationMethods: ROS was measured by the flow of cytometry. The phosphorylation of p38MAPK induced by ox-LDL was determined by Western blot. Oxidized LDL was quantified by TBARS evaluation.Results: A small dose of GB (25μg/ml) inhibited the oxidation of LDL. The oxidative degree of MDA was almost equal to that of the LDL group, however, high doses of GB didn't have the inhibitory effect. ROS generation and p38MAPK phosphorylation was individually increased after stimulation with ox-LDL (300μg/ml) for 5 hours and ox-LDL (1mg/ml) for 16 hours in HUVEC. Ginkgolide B inhibited the production of ROS according to the concentration of dose and manner. Meanwhile, GB (300μg/ml) inhibited p38MAPK phosphorylation effectively.2. The inhibitory effect of GB on inflammatory proteinMethods: The activation of NF-kB was determined by immuno-fluorescence evaluation. The expression of ICAM-1 and COX-2 as well as phosphorylation of IkB were determined by Western blot.Results: After stimulation with ox-LDL(1mg/ml)we detected with the fluorescent microscope that the activated NF-kB entered the intranuclear portion. GB(500μg/ml)effectively inhibited the activation. The same results were confirmed indirectly by measuring the tendency of IkB phosphorylation. After administrating ox-LDL(1mg/ml), GB inhibited the increase of the phosphorylation of p38MAPK and expression of ICAM-1, but had no inhibitory effect on COX-2.