The Preliminary Studies On The Effects Of Riparsaponin On The Activity Of The Gout-related Enzymes

【OBJECTIVE】To study the activity of Riparsaponin on some enzymes related to gout and hyperuricemia that include XOD,HGPRT,PRPP,PRPS and phosphoribosyl pyrophosphate transferase amide in vitro.【METHOD】Fluorimetric analysis.was used to evaluate Riparsaponin on the effects of xanthine oxidase with 96 well plate in vitro,The final concentrations of allopurinol group were 2.20nmol/ml,4.41nmol/ml,8.82nmol/ml,17.63nmol/ml,35.27nmol/ml and 70.53nmol/ml respectively,that of Riparsaponin were 4.84nmol/ml,9.68nmol/ml,19.36nmol/ml,40.32nmol/ml,80.65nmol/ml and 161.29nmol/ml respectively.each concentration with five parallel wells.The value of fluorescence were determined by the chemiluminescence fluorescence detector at the excitation wave/launch wave of 380nm/440nm.inhibition ratio and value of IC50 were calculated for evaluating the influence of Riparsaponin to XOD in vitro.The m-RNA expression of HGPRT,PRPP,PRPS and PRPPAT on action of various concentrations of Riparsaponin were detected with Western Blot.The final concentrations of Riparsaponin were 4.84nmol/ml,9.68 nmol/ml,19.36nmol/ml,40.32nmol/ml and 80.65nmol/ml.That of allopurinol were 4.41nmol/ml,8.82nmol/ml ane 17.63nmol/ml,each concentration with 3 parallel wells.The cells for RNA extraction were assembled after 24h.【RESULT】The method of fluorimetric analysis used in detection of activity of xanthine oxidase was convenient and reliable.The inhibition of Riparsaponin to xanthine oxidase enhance with the concentration.IC50 was 11.16nmol/ml for Riparsaponin and 11.84 nmol/ml for allopurinol.The diagram of inhibition ratio of xanthine oxidase showed that both are the competitive inhibitors of xanthinoxidase.The mRNA expression quantity of HGPRT in five different dosage-groups was significant increased compared with comtrol group(p＜0.01)in the experiment.The mRNA expression quantity of PRPS in the 9.68 nmol/ml-dosage-group was reduced compared with comtrol group(p＜0.05),and the 19.36nmol/ml,40.32nmol/ml,80.65nmol/ml-dosage-groups were significant reduced compared with comtrol group(p＜0.01).Also The mRNA expression quantity of PRPPAT in five different dosage-groups was significant reduced compared with comtrol group(p＜0.01).【CONCLUSION】This study shows that to evaluate the Riparsaponin on the effects of enzyme correlate with gout(XOD,HGPRT,PRPP,PRPS,PRPP)by fluorimetric analysis and RT-PCR in vitro,Riparsaponin showed the inhibite action on activities of XOD,PRPS,PRPPAT,and enhance on HGPRT.