Abstract
In our continuing efforts to identify effective naturally sourced agents for
diabetic complications, five caffeoylated phenylpropanoid glycosides,
acteoside (1 ), isoacteoside (2 ), poliumoside (3 ),
brandioside (4 ), and pheliposide (5 ) were isolated from the
80 % EtOH extract of Brandisia hancei stems and leaves. These
isolates (1 –5 ) were subjected to an in vitro bioassay
evaluating their inhibitory activity on advanced glycation end product
formation and rat lens aldose reductase activity. All tested compounds
exhibited significant inhibition of advanced glycation end product formation
with IC50 values of 4.6–25.7 µM, compared with those of
aminoguanidine (IC50 = 1056 µM) and quercetin
(IC50 = 28.4 µM) as positive controls. In the rat lens aldose
reductase assay, acteoside, isoacteoside, and poliumoside exhibited greater
inhibitory effects on rat lens aldose reductase with IC50 values
of 0.83, 0.83, and 0.85 µM, respectively, than those of the positive
controls, 3,3-tetramethyleneglutaric acid (IC50 = 4.03 µM) and
quercetin (IC50 = 7.2 µM). In addition, the effect of acteoside
on the dilation of hyaloid-retinal vessels induced by high glucose in larval
zebrafish was investigated. Acteoside reduced the diameters of high
glucose-induced hyaloid-retinal vessels by 69 % at 10 µM and 81 % at 20 µM,
compared to the high glucose-treated control group. These results suggest
that B. hancei and its active components might be beneficial in the
treatment and prevention of diabetic vascular complications.
Key words
Brandisia hancei
- Scrophulariaceae - phenylpropanoid glycoside - advanced glycation end-product -
rat lens aldose reductase - zebrafish - diabetic vascular complications
