No abstract

Acylated phenylethanoid glycosides, echinacoside (1) and acteoside (2), principal constituents in stems of Cistanche tubulosa (Orobanchaceae), inhibited the increase in postprandial blood glucose levels in starch-loaded mice at doses of 250-500 mg/kg p.o. These compounds (1 and 2) also significantly improved glucose tolerance in starch-loaded mice after 2 weeks of continuous administration at doses of 125 and/or 250 mg/kg/day p.o. without producing significant changes in body weight or food intake. In addition, several constituents from C. tubulosa, including 1 (IC50 = 3.1 μM), 2 (1.2 μM), isoacteoside (3, 4.6 μM), 2'-acetylacteoside (4, 0.071 μM), tubulosides A (5, 8.8 μM) and B (9, 4.0 μM), syringalide A 3-O-α-L-rhamnopyranoside (10, 1.1 μM), campneoside I (13, 0.53 μM), and kankanoside J1 (14, 9.3 μM), demonstrated potent rat lens aldose reductase inhibitory activity. In particular, the potency of compound 4 was similar to that of epalrestat (0.072 μM), a clinical aldose reductase inhibitor.

No abstract