RESUMO
The prevention of amyloid aggregation is promising for the treatment of age-related diseases such as Alzheimer's (AD) and type 2 diabetes (T2D). Ten antioxidant flavonoids isolated from the medicinal halophyte Tamarix gallica were tested for their amyloid aggregation inhibition potential. Glucuronosylated flavonoids show relatively strong inhibitory activity of Amyloid ß (Aß) and human islet amyloid polypeptide (hIAPP) aggregation compared to their aglycone analogs. Structure-activity relationship of the flavonoids suggests that the catechol moiety is important for amyloid aggregation inhibition, while the methylation of the carboxyl group in the glucuronide moiety and of the hydroxyl group in the aglycone flavonoids decreased it.
Assuntos
Doença de Alzheimer/metabolismo , Amiloide/metabolismo , Antioxidantes/farmacologia , Diabetes Mellitus Tipo 2/metabolismo , Flavonoides/farmacologia , Tamaricaceae , Amiloide/antagonistas & inibidores , Antioxidantes/isolamento & purificação , Flavonoides/isolamento & purificação , Humanos , Componentes Aéreos da Planta , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Agregação Patológica de Proteínas/metabolismoRESUMO
O-Methylated and glucuronosylated flavonoids were isolated from Tamarix gallica as α-glucosidase inhibitors. Structure-activity relationship of these flavonoids suggests that catechol moiety and glucuronic acid at C-3 are factors in the increase in α-glucosidase inhibitory activity. Furthermore, rhamnetin, tamarixetin, rhamnazin, KGlcA, KGlcA-Me, QGlcA, and QGlcA-Me exhibit synergistic potential when applied with a very low concentration of acarbose to α-glucosidase from rat intestine.
