The Research Of Drug-Drug Interaction Leads By The Innihbition Effect Of Ginsenoside Metabolites And Glabridin Toward Carboxylesterases

ObjectiveThe purpose of the experiment is to research the drug-drug interaction（DDI）of ginsenoside matebolites and glabridin with the coadministrating drug that hydrolysed by carboxylesterase 1 and carboxylesterase 2,which is induced by the inhibition effect of ginaenosides and glabridin toward carboxylesterase 1（h CE1）and carboxylesterase 2（h CE2）.Coadministrate ginsenosides and carboxylesterase metabolite’s drugs may have a synergy effect or will reduce some adverse reaction.Furthermore,providing a more favorable dosing regimen for clinical application and increaseing the safety and effectiveness of drugs coadministrating.MethodsA vitro typical incubation mixture with a total volume of 0.2m L contain human liver microsomes（HLM）（2μg/m L）,0.1 M potassium phosphate（PH=7.4）to simulate the condition of human physiological environment to process the enzymatic reaction.Adding inhibitors and fluorescent substrate to initiate the enzymatic reaction,ethanol instead of inhibitor act as a negative control.Decteced by Synergy H1 Hybrid Multi-Mode Microplate Reader to calculate the residual activity（%）.With the common strong inhibitor Bis-p-nitrophenyl phosphate as a positive control to verify the reliability of the experimental results.Through further kinetic inhibition experimental to determinate the half inhibitory concentration(IC₅₀),inhibition constant（Ki）and inhibition kinetic type of ginsenosides and glabridin towards carboxylesterases.ResultsAs the result that the seventeen ginsenosides and glabridin have no significant inhibition effect toward carboxulesterase 1.However 20（S）-protopanaxadiol（Ppd）,20（S）-protopanaxatriol（Ppt）,ginsenoside compound K,ginsenoside F2,panaxadiol and glabridin have strong inhibition effect toward carboxylesterase 2.The half inhibitory concentration(IC₅₀)values of 20（S）-protopanaxadiol（Ppd）,20（S）-protopanaxatriol（Ppt）,ginsenoside compound K,panaxadiol,ginsenoside F2 and glabridin are 2.658±0.758 μM,9.800±0.791 μM,8.707±2.077 μM,9.619±1.937 μM,20.770±4.779 μM and 0.891±0.127 μM respectively.The inhibition constant（Ki）values of 20（S）-protopanaxadiol（Ppd）,20（S）-protopanaxatriol（Ppt）,ginsenoside compound K,panaxadiol,ginsenoside F2 and glabridin are 1.523 μM,8.929 μM,7.563 μM,5.455 μM,6.287 μM and 1.955 μM respectively.The inhibition type of 20（S）-protopanaxadiol（Ppd）,20（S）-protopanaxatriol（Ppt）and ginsenoside compound K are uncompetive inhibition type,and the inhibition type of panaxadiol,ginsenoside F2 and glabridin are mixed inhibition type.Conclusions Reference to the half inhibitory concentration(IC₅₀)value and the inhibition constant values of 20（S）-protopanaxadiol（Ppd）,20（S）-protopanaxatriol（Ppt）,ginsenoside compound K,panaxadiol,ginsenoside F2 and glabridin,draw a conclusion that 20（S）-protopanaxadiol（Ppd）,20（S）-protopanaxatriol（Ppt）and ginsenoside compound K（C-K）,panaxadiol and glabridin are the Strong inhibitors of carboxylesterase 2.The anti-cancer drug irinotecan,commonly used in clinical,hydrolysed by h CE2 to the metabolic activity product SN-38 in the gut can cause delayed diarrhea adverse symptoms,induced by the accumulation of a large number SN-38.There had reported that the inhibitors of carboxylesterase 2 will reduce the delayed diarrhea adverse symptoms.Such as fluorene analogs,nitrobenzene derivatives and sulfonamide derivatives as selective inhibitors of intestinal carboxylesterase 2 is expected to reduce the delayed diarrhea adverse symptoms of SN-38.Reference to the previous reports,the maximum concentration values of 20（S）-protopanaxadiol（Ppd）,20（S）-protopanaxatriol（Ppt）and ginsenoside compound K,in human gut.Draw this conclusion: Ppd,Ppt and C-K as the strong inhibitors can effectively inhibitate the intestinal h CE2 activity to mitigate the delayed diarrhea adverse symptoms.Thus not only achieve the synergistic anti-tumor effect after common use of ginsenosides and irinotecan,but also reduce the delayed diarrhea symptoms.Glabridin also can be used as the strong inhibitor of carboxylesterase 2 to reduce the delayed diarrhea side effects of irinotecan.There remains a need for further animal experiments to vertificate.As the same time,according to the analysis of the regularity between the hydrolytic activity and ginsenosides’ structure,a new more strong inhibitor is design to reduce or prevent the delayed diarrhea side effects of irinotecan,without any side effects.