Flavonoids from Litsea japonica Inhibit AGEs Formation and Rat Lense Aldose Reductase In Vitro and Vessel Dilation in Zebrafish.
In our ongoing efforts to identify effective naturally sourced agents for the treating of diabetic complications, two new (1and2) and 11 known phenolic compounds (3-13) were isolated from an 80 % ethanol extract ofLitsea japonicaleaves. The structures of the new compounds were established by spectroscopic and chemical studies. These isolates (1-13) were subjected to anin vitrobioassay evaluating their inhibitory activity on advanced glycation end products formation and rat lens aldose reductase activity. Of the compounds evaluated, the flavonoids (3, 4, 6-8, 11, and12) markedly inhibited advanced glycation end products formation, with IC50values of 7.4-72.0 µM, compared with the positive control, aminoguanidine (IC50= 975.9 µM). In the rat lens aldose reductase assay, consistent with the inhibition of advanced glycation end products formation, the flavonoids (3, 4, 6-8, 11, and12) exhibited considerable inhibition of rat lens aldose reductase activity, with IC50values of 1.1-12.5 µM. In addition, the effects of kaempferol (4) and tiliroside (7) on the dilation of hyaloid-retinal vessels induced by high glucose in larval zebrafish were investigated. Only kaempferol significantly reduced the diameters of high glucose-induced hyaloid-retinal vessels, by 52.2 % at 10 µM, compared with those in the high glucose-treated control group.
KM Convergence Research Division, Korea Institute of Oriental Medicine, Daejeon, Republic of Korea.
Ik-Soo
IS
Lee
KM Convergence Research Division, Korea Institute of Oriental Medicine, Daejeon, Republic of Korea.
Yu Jin
YJ
Kim
KM Convergence Research Division, Korea Institute of Oriental Medicine, Daejeon, Republic of Korea.
Seung-Hyun
SH
Jung
Department of Life Science, Gachon University, Seongnam, Republic of Korea.
Joo-Hwan
JH
Kim
KM Convergence Research Division, Korea Institute of Oriental Medicine, Daejeon, Republic of Korea.
Jin Sook
JS
Kim
D000449:Aldehyde Reductase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D000818:Animals; D003925:Diabetic Angiopathies / Q000139:chemically induced; D004195:Disease Models, Animal; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D017127:Glycation End Products, Advanced / Q000037:antagonists & inhibitors* / Q000378:metabolism; D006146:Guanidines / Q000494:pharmacology; D066298:In Vitro Techniques; D020128:Inhibitory Concentration 50; D007908:Lens, Crystalline / Q000201:enzymology*; D032862:Litsea / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D012171:Retinal Vessels / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D015027:Zebrafish
D005419:Flavonoids; D017127:Glycation End Products, Advanced; D006146:Guanidines; D010936:Plant Extracts; C052083:tiliroside; D000449:Aldehyde Reductase; C004479:pimagedine