title: Inhibitory effects of Colocasia esculenta (L.) Schott constituents on aldose reductase.
abstract: The goal of this study was to determine the rat lens aldose reductase-inhibitory effects of 95% ethanol extracts from the leaves of C. esculenta and, its organic solvent soluble fractions, including the dichloromethane (CH2Cl2), ethyl acetate (EtOAc), n-butanol (BuOH) and water (H2O) layers, using dl-glyceraldehyde as a substrate. Ten compounds, namely tryptophan (1), orientin (2), isoorientin (3), vitexin (4), isovitexin (5), luteolin-7-O-glucoside (6), luteolin-7-O-rutinoside (7), rosmarinic acid (8), 1-O-feruloyl-d-glucoside (9) and 1-O-caffeoyl-d-glucoside (10) were isolated from the EtOAc and BuOH fractions of C. esculenta. The structures of compounds 1-10 were elucidated by spectroscopic methods and comparison with previous reports. All the isolates were subjected to an in vitro bioassay to evaluate their inhibitory activity against rat lens aldose reductase. Among tested compounds, compounds 2 and 3 significantly inhibited rat lens aldose reductase, with IC50 values of 1.65 and 1.92 μM, respectively. Notably, the inhibitory activity of orientin was 3.9 times greater than that of the positive control, quercetin (4.12 μM). However, the isolated compounds showed only moderate ABTS+ [2,29-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)] activity. These results suggest that flavonoid derivatives from Colocasia esculenta (L.) Schott represent potential compounds for the prevention and/or treatment of diabetic complications.
authors.affiliation: Department of Pharmacology, College of Medicine, Hallym University, 200-702 Chuncheon, Korea. lihm@hallym.ac.kr.
authors.forename: Hong Mei
authors.initials: HM
authors.lastname: Li
authors.affiliation: Department of Food and Nutrition, Hallym University, 200-702 Chuncheon, Korea. isohsh@gmail.com.
authors.forename: Seung Hwan
authors.initials: SH
authors.lastname: Hwang
authors.affiliation: Department of Food and Nutrition, Hallym University, 200-702 Chuncheon, Korea. kbgda87@naver.com.
authors.forename: Beom Goo
authors.initials: BG
authors.lastname: Kang
authors.affiliation: Department of Physical Education, Hallym University, 200-702 Chuncheon, Korea. jayshong@hallym.ac.kr.
authors.forename: Jae Seung
authors.initials: JS
authors.lastname: Hong
authors.affiliation: Department of Food and Nutrition, Hallym University, 200-702 Chuncheon, Korea. limss@hallym.ac.kr.
authors.forename: Soon Sung
authors.initials: SS
authors.lastname: Lim
mesh_terms: D000449:Aldehyde Reductase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D000818:Animals; D031060:Colocasia / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D000449:Aldehyde Reductase