RESUMEN
Rugosin G, an ellagitannin trimer, was isolated from the water-soluble fraction of red rose petals, and its inhibitory activity against recombinant human histidine decarboxylase was investigated. Rugosin G showed potent inhibition compared to ellagitannin monomers and a dimer with macrocyclic structure (oenothein B), suggesting the potent inhibition of rugosin G was attributed to its linear oligomeric conformation. Abbreviations: HDC, histidine decarboxylase; Me2CO, acetone; EtOAc, ethyl acetate.
Asunto(s)
Histidina Descarboxilasa/antagonistas & inhibidores , Taninos Hidrolizables/química , Taninos Hidrolizables/farmacología , Estructura Molecular , Extractos Vegetales/química , Proteínas Recombinantes/efectos de los fármacos , Rosa/químicaRESUMEN
Histidine decarboxylase (HDC) catalyses the formation of histamine, a bioactive amine. Agents that control HDC activity are beneficial for treating histamine-mediated symptoms, such as allergies and stomach ulceration. We searched for inhibitors of HDC from the ethyl acetate extract of the petal of Filipendula ulmaria, also called meadowsweet. Rugosin D, rugosin A, rugosin A methyl ester (a novel compound), and tellimagrandin II were the main components; these 4 ellagitannins exhibited a non-competitive type of inhibition, with K(i) values of approximately 0.35-1 µM. These K(i) values are nearly equal to that of histidine methyl ester (K(i)=0.46 µM), an existing substrate analogue inhibitor. Our results show that food products contain potent HDC inhibitors and that these active food constituents might be useful for designing clinically available HDC inhibitors.