Synthesis And Specific Target Identification Of Piperic Acid Molecule Probe

Lidpid-lowering is one of the important measures to prevent cardiovascular diseases and atherosclerosis.Drug treatment can reduce the patient's serum cholesterol levels and significantly reduce the mortality rate of cardiovascular disease.Statins are effective inhibitors of the rate-limiting enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase during cholesterol biosynthesis in mammals.Statins can reduce blood fat and achieve the purpose of prevention and treatment of cardiovascular disease.So it has been the most extensive clinical application.However,statins have undesirable side effects.Therefore,the research and development of efficient cholesterol-lowering drug with low toxicity has a very important value on China's Population Health.Natural product piperlonguminine has a significant hypolipidemic effect and much lower toxicity compared to statins.In this thesis,first,using succinic anhydride ? propargyl amine hydrochloride ?N-Boc-L-lysine methyl ester hydrochloride?GBH?AEBSF?azidobenzyl alcohol as a raw material,two sets of activity-based small molecule probe(ABP)and their negative control probe contaning piperlonguminine active groups,photocrossling groups and alkynyl groups were synthesized.All compounds were characterized by NMR spectroscopy and mass spectrometry.Secondly,by MTT assay proved that all synthesized active small molecules have negligible cytotoxicity.Total protein is extracted from mouse liver tissue and the concentration was measured by the BCA method.Then,the probes were mixed with the total protein and a bio-orthogonal reaction(Cu-catalyzed "Click" reaction)was conducted after a brief UV crosslinking.Finally,streptavidin was used for enrichment of the piperlonguminine probe-target protein complex.Differences between probes in the experimental and control groups were compared by polyacrylamide gel electrophoresis.The results showed that the experimental group(piperlonguminine probe)specifically bind with a protein with molecular weight of 20 KDa of mouse liver tissue.This result lays the foundation for the follow-up studies on the mechanism of hypolipidemic piperlonguminine.