RESUMEN
A novel 13-membered ring thiocyclitol, isolated from an aqueous extract of Kothala-himbutu (Salacia reticulata), inhibited alpha-glucosidase in vitro. The inhibitory activity was investigated by maltose- and sucrose-loading on Wistar rats. This study found significant lowering of postprandial glucose levels, and the potency of 13-membered ring thiocyclitol was confirmed in vivo.
Asunto(s)
Ciclitoles/farmacología , Inhibidores Enzimáticos/farmacología , Inhibidores de Glicósido Hidrolasas , Salacia/química , Animales , Glucemia/efectos de los fármacos , Ciclitoles/aislamiento & purificación , Inhibidores Enzimáticos/aislamiento & purificación , Hipoglucemiantes/aislamiento & purificación , Hipoglucemiantes/farmacología , Maltosa/sangre , Periodo Posprandial , Ratas , Ratas Wistar , Sacarosa/sangreRESUMEN
A polyhydroxylated cyclic 13-membered sulfoxide (1) was isolated from an aqueous extract of Kothala-himbutu ( Salacia reticulata WIGHT). The structure of compound 1 was elucidated by 1D and 2D NMR and APCI-MS methods. The alpha-glucosidase inhibitory activity of compound 1 (IC 50: maltase, 0.227 microM; sucrase, 0.186 microM; isomaltase, 0.099 microM) was much greater than the inhibitory activity of salacinol and kotalanol, which were previously isolated from Kothala-himbutu.
Asunto(s)
Inhibidores de Glicósido Hidrolasas , Compuestos Heterocíclicos con 1 Anillo/aislamiento & purificación , Compuestos Heterocíclicos con 1 Anillo/farmacología , Plantas Medicinales/química , Salacia/química , Compuestos de Azufre/aislamiento & purificación , Compuestos de Azufre/farmacología , Animales , Compuestos Heterocíclicos con 1 Anillo/química , Intestino Delgado/enzimología , Estructura Molecular , Monosacáridos/química , Monosacáridos/aislamiento & purificación , Páncreas/enzimología , Ratas , Sri Lanka , Sacarasa/efectos de los fármacos , Alcoholes del Azúcar/química , Alcoholes del Azúcar/aislamiento & purificación , Sulfatos/química , Sulfatos/aislamiento & purificación , Compuestos de Azufre/química , Porcinos , alfa-Amilasas/antagonistas & inhibidores , alfa-Glucosidasas/efectos de los fármacosRESUMEN
B. Ludvik et al., have recently shown the effect of Caiapo (Ipomoea batatas L.) on reducing fasting blood glucose and insulin resistance in type-2 diabetic patients. It, however, was required 2-4 weeks after the single administration of Caiapo. The present study aimed to determine if the combination therapy of Caiapo with a mulberry leaf powder, which inhibits alpha-glucosidase, or with a loquat leaf extract, which shows an insulin-like effect, could make it possible to enhance the antidiabetic activities of Caiapo, and to shorten the time necessary for the inhibition of increasing blood glucose levels. A mixture of the pulverized tuber of Caiapo (357 mg/kg) and the mulberry leaf powder (143 mg/kg), or a mixture of the pulverized skin of Caiapo (194 mg/kg) and the powdered loquat leaf extract (6 mg/kg) was orally administered to 6 weeks-old male KK-Ay mice for 28 days and the glucose loading test was conducted every 7 days. In the glucose loading test after one week feeding, a reduction in blood glucose concentration after 60 minutes of the administration of glucose was observed in both mixture groups against the control group (p < 0.05) in the case of Caiapo only, similar delayed effects were seen in 2-3 weeks after feeding.