Synthesis And Activity Of Some Serum Aromatic Esterase Activators And Inhibitors

Paraoxonase 1（PON1）is an important hydrolytic enzyme in the human body and it can hydrolyze many substrates such as paraoxon,aromatic esters,and lactones.Furthermore,its activity is related to cardiovascular diseases,type 2 diabetes,and cancer.Therefore,activators of PON1 are expected to prevent or treat the above diseases.Ginger shows anti-oxidation,anti-atherosclerosis,immunity enhancement and other pharmacological effects.The previous research of our group found that that ginger extract and the pure components of ginger 6-shogaol can stimulate PON1 activity.Therefore,it is of great significance to further confirm the effect and mechanism of the activator or inhibitor of PON1 in ginger.The activator 6-shogaol is derived in order to obtain compounds with stronger activating effects.The effects on serum PON1 activity of p-coumaric acid and 6-gingerol,which were extracted from ginger,were evaluated by ultraviolet spectrophotometry with phenyl acetate as substrate and chemiluminescence with acridinium ester as substrate.Both p-coumaric acid and 6-gingerol inhibited the PON1 activity,reducing the binding affinity between the enzyme and the substrate.According to the inhibition constant,IC₅₀,hydrolysis kinetic constant,6-gingerol showed a greater inhibitory effect than p-coumaric acid.And p-coumaric acid inhibited the hydrolysis of acridinium ester and phenyl acetate in serum PON1 in a mixed manner,while 6-gingerol was mixed inhibitor of serum PON1 hydrolyzes phenyl acetate,and competitively inhibited enzymatic hydrolysis of acridinium esters.Mono-or poly-substituted benzaldehydes such as nitro,methoxy,hydroxy,etc.undergo Aldol reaction to synthesize short-chain analogues of 6-shogaol.The benzaldehyde substituted with electron withdrawing group reacted with acetone more easily,and the reaction time was shorter,but it was easier to produce by-products.After structural characterization,ultraviolet spectrometry using dihydrocoumarin as substrate and the chemiluminescence method with acridinium ester as the substrate were used to evaluate the effects of 6-shogaol short-chain analogues on the activity of serum PON1lactonase and aromatic esterase.The activity evaluation found that among the 9synthesized short-chain analogues,compound D1 showed the strongest activated activity of serum PON1 aromatic esterase,but its activated effect was weaker than that of 6-shogaol.And compounds B2 and H1 had the strongest inhibitory effects,but the inhibitory effects were weaker than the inhibitory effect of 6-gingerol.Compound G2had the strongest activated effect on serum PON1 lactonase activity,while compound B2 had the strongest inhibitory effect.Finally,using GOLD software for molecular docking,selected PON1 crystal structure（PDB ID:3SRG）to establish a docking model,and explored the affinity of small molecules with PON1.The results of molecular docking with 2-hydroxyquinoline as the docking center were consistent with the results of the activity test,which is more suitable for the docking of the inhibitors with PON1.