Aldose reductase inhibitors from the leaves of Myrdaria dubia (H. B. & K.) McVaugh

Kobe Pharmaceutical University, Higashinada-ku, Kobe, 658-8558 Japan.
Phytomedicine (Impact Factor: 2.88). 11/2004; 11(7-8):652-6. DOI: 10.1016/j.phymed.2003.12.002
Source: PubMed

ABSTRACT Ellagic acid (1) and its two derivatives, 4-O-methylellagic acid (2) and 4-(alpha-rhamnopyranosyl)ellagic acid (3) were isolated as inhibitors of aldose reductase (AR) from Myrciaria dubia (H. B. & K.) McVaugh. Compound 2 was the first isolated from the nature. Compound 3 showed the strongest inhibition against human recombinant AR (HRAR) and rat lens AR (RLAR). Inhibitory activity of compound 3 against HRAR (IC50 value = 4.1 x 10(-8) M) was 60 times more than that of quercetin (2.5 x 10(-6) M). The type of inhibition against HRAR was uncompetitive.

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