丹参二萜醌对黄嘌呤氧化酶活性的抑制作用(英文)

Inhibition of diterpenoid tanshinones from Salvia miltiorrhiza Bge. on xanthine oxidase activity

目的黄嘌呤氧化酶(XOD)抑制剂对痛风或其他XOD诱导的疾病有潜在的治疗作用,因此探讨了从丹参(Salvia miltiorrhiza Bge.)中分离的丹参二萜醌---隐丹参酮(CT)和次甲丹参酮(MT)对XOD的抑制作用。方法在分子氧存在的条件下,XOD催化黄嘌呤产生尿酸和超氧阴离子。在黄嘌呤/XOD的反应媒介中加入CT或MT,通过测量波长290nm处吸光度的增加测定尿酸形成速率。结果CT和MT对XOD有抑制作用,酶动力学曲线Dixon图显示抑制方式是竞争型。CT和MT的Ki值分别为17.8和25.9μmol.L-1,抑制活性与浓度正相关。CT和MT的IC50值分别为70和67μmol.L-1,阳性对照别黄嘌呤醇的IC50值为60μmol.L-1。结论CT和MT对XOD活性有抑制作用,对痛风或其他XOD诱导的疾病可能有一定的治疗作用。

AIM Inhibitors of xanthine oxidase （XOD） may be potentially useful for the treatment of gout or other XOD inducing diseases, so the inhibition on XOD activity of diterpenoid tanshinones such as cyptotanshinone （CT） and methylenetanshinone （MT） from Tanshen （Salvia miltiorrhiza Bge. ） was studied. METHODS The formation rate of uric acid from xanthine was determined by measuring the absorbance increment at 290 nm （△A290m ） in the reactive medium of xanthine/ XOD when CT or MT was added. RESULTS It was found that CT and MT inhibited XOD activity. Dixon plots showed that the inhibition mode was competitive type. The Ki values of CT and MT were 17.8 μmol·L^- 1 and 25.9 μmol· L^- 1, respectively. Their inhibitory potencies positively correlated with their concentrations and the IC50 values of CT and MT were 70 and 67 μmol·L^- 1, respectively. The IC50 value of allopurinol, the positive control, was 60 μmol· L^-1. CONCLU- SION CT and MT have inhibitory effects on XOD activity and may be potentially useful for the treatment of gout or other XOD inducing diseases.