생약으로부터 산화적 결합 효소인 갑상선 peroxidase의 저해제 검색

Screening of Inhibitor of Thyroid Perocidase, an Ocidative Coupling Enzyme from Natural Products

Thyroid peroxidase is a biochemical target protein for the antithyroid drugs. Ethanol extracts from one hundred and thirty seven natural products were screened for the inhibition of thyroid peroxidase activity. Thyroid peroxidase was purified from porcine thyroids, and the inhibition of peroxidase activity was evaluated using guaiacol oxidation (C-C coupling) assay. Twenty one natural products expressed a remarkable inhibition (>50%) of peroxidase activity at 330mcg solid weight/ml. The 50% inhibitory concentration (IC50) of 70% ethanol extract from six potent natural products ranged from 3.1 to 31.2mcg solid weight/ml, in contrast to the range (0.33~0.54mcg/ml) of IC50, values for catechin and epigallocatechin gallate as positive controls. Noteworthy, the extract of Camellia taliensis showed an irreversible inhibition of the enzyme. It is suggested that extract from some natural products such as Camellia taliensis, Rheum undulatum or Euphorbia pekinsis, exhibiting a potent inhibition of peroxidase activity, may be developed as sources of potent antithyroid agents.