• ALGAE
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• 제19권4호
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• pp.349-352
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• 2004

We examined MeOH extracts of the marine plants from Korea for their inhibitory activities on rat lens aldose reductase in vitro. Among the MeOH extracts tested, the extracts of Enteromorpha prolifera, Ecklonia cava, Pelvetia siliquosa and Salicornia herbacea exhibited a rat lens aldose reductase inhibition (IC$_{50}$: 3.04, 8.84, 11.42 and 4.99 $\mu$g-ml$^{-1}$, respectively) in vitro.

• Journal of the Korean Wood Science and Technology
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• 제38권2호
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• pp.159-164
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• 2010

Nine compounds, caffeic acid, naringenin, apigenin, luteolin, kaempferol, verbascoside, isoverbascoside, isocampneoside II, and cistanoside F, were isolated from the EtOAc and n-BuOH fractions of P. coreana bark. The structures of these compounds (1-9) were elucidated by spectroscopic methods and literature data. All the isolates were subjected to in vitro bioassay to evaluate their inhibitory activity against rat lens aldose reductase. Among these, compounds 6 and 8 indicated the significant inhibitory activity on rat lens aldose reductase with $IC_{50}$ values of 2.67 and 5.59 ${\mu}M$, respectively. Especially, The inhibition activity of acteoside was 3.9 times better than that of quercetin as a positive control (10.6 ${\mu}M$). These results suggested that phenylethanoid glycosides are likely to be the potential compounds for the prevention and/or treatment of diabetic complications.

• Preventive Nutrition and Food Science
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• 제14권4호
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• pp.358-361
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• 2009

Aldose reductase was purified to electrophoretic homogeneity from porcine liver. The purified enzyme was a monomer of 36 kDa. The enzyme was strongly inhibited by $Cu^{2+}\;and\;Mg^{2+}$ ions. Incubation of the enzyme with pyridoxal 5'-phosphate led to complete inhibition of enzymatic activity, suggesting that lysine residue is involved at or near the active site of the enzyme. The enzyme exhibited a broad substrate specificity. Furthermore, the enzyme was capable of decolorizing Alizarin, an anthraquinone dye.

• Archives of Pharmacal Research
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• 제8권4호
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• pp.273-275
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• 1985

Carvomethone, (+) pulegone, (-)isopulegol and (-) menthone, which are natural and widely distributed in the plantkingdom, were examined for their Lens Aldose Reductase inhibitory effects. All monoterpenes tested showed that the mild inhibitory effects. Inhibition percents of four monoterpenes were in the range of 23-42% at $10^{-3}M$ and 5-21% at $10^{-4}M$.

• 농업과학연구
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• 제39권1호
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• pp.69-73
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• 2012

The purpose of this study was to evaluate the potential of naturally occurring aldose reductase (AR) inhibitors from white-color natural products (Aruncus dioicus var. kamtschaticus, Chionanthus retusa, Cosmos bipinnatus, Hibiscus syriacus, Hydrangea paniculata, Magnolia denudata, Prunus padus, Robinia pseudo-accacia, Rhododendron mucronulatum for. albiflorum, Spiraea blumei, and Spiraea prunifolia var. simpliciflora). The MeOH extract of white-color natural products were tested on rat lens AR inhibition in vitro. Among them, the MeOH extract of R. mucronulatum for. albiflorum showed highest inhibition on AR ($IC_{50}$ value, 1.07 ${\mu}g/ml$). These results suggested that R. mucronulatum for. albiflorum, a white-color natural product, could be a useful resource in the development of a novel AR inhibitory agent against diabetic complications.

• Journal of Applied Biological Chemistry
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• 제60권1호
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• pp.29-33
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• 2017

The methanol extract of Rhododendron mucronulatum for. albiflorum (RMFA) stems inhibited aldose reductase (AR) activity. The RMFA fractions obtained by stepwise extraction with solvents of different polarity were tested for AR inhibition in vitro using the lens of a rat. Among them, the ethyl acetate (EtOAc) fraction inhibited AR more than the other fractions. Quercetin (1) from the EtOAc fraction showed a high AR inhibition with $IC_{50}$ of $2.11{\mu}M$. The stems of RMFA contained the highest amount (5.12 mg/g extract) of quercetin. Our results suggest that RMFA, which contained quercetin, could be a useful material for the development of supplementary functional foods.

• 농업과학연구
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• 제40권1호
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• pp.47-51
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• 2013

To search for the aldose reductase (AR) inhibitors from Korean folk plants, the inhibition of rat lens AR in vitro using the methanol (MeOH) extracts from Korean folk plants in Chungcheong Province was investigated. Among Korean folk plants tested, the MeOH extract of Persicaria longiseta showed highest inhibition of AR ($IC_{50}$ value, $5.14{\mu}g/ml$). Consequently, P. longiseta has a possibility of new natural resources for the development of AR inhibitor for the prevention of diabetic complications.

• Archives of Pharmacal Research
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• 제18권2호
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• pp.65-68
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• 1995

The methanol extract from the whole parts of the flowers of Chrysanthemum boreals was found to exhibit a significant inhibition of a rat lens aldose reductase (RLAR) activity in vitro. Bioassay guided systematic fractionation of the methanol extract led to the isolation of four flavonoids which were identified as acacetin (1), apigenin (II), luteolin (III) and linarin (IV). Compounds I-III were demonstrated to exhibit a significant inhibition of RLAR. Luteolin (II) was found to be the most potent AR inhibitor with $IC_{50}$ value of $5{\times}10^{-7}M$.

• Bulletin of the Korean Chemical Society
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• 제25권12호
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• pp.1874-1876
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• 2004

Quantitative structure activity relationship has been probed for spirosuccinimide-fused tetrahydropyrrolo[1,2-a]pyrazine-1,3-dione derivatives acting as aldose reductase inhibitors. While the spirosuccinimide compounds contain a chiral center, the aldose reductase inhibition assay was performed with racemic mixtures in the published work. As the physicochemical descriptors of the QSAR analysis must be evaluated for a definite molecular structure, we devise a new 'racemic' descriptor as the arithmetic mean of the (R)-enantiomer descriptor and the (S)-enantiomer descriptor. The resultant QSAR model derived from the racemic descriptors outperforms the original QSAR models, closely reproducing the observed activity of optically pure enantiomers as well as racemic mixtures.

• Natural Product Sciences
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• 제10권1호
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• pp.35-39
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• 2004

Aldose reductase (AR), the key enzyme of the polyol pathway, is known to play important roles in the diabetic complications. The inhibitors of AR, therefore, would be potential agents for the prevention of diabetic complications. In order to clarify the structural requirements of flavonoids for aldose reductase inhibitory activity, thirty flavonoids were examined. Among the thirty flavonoids, flavonols such as quercetin (5), reyneutrin (7), quercitrin (9), isoquercitrin (11), and avicularin (14) were found to exhibit much stronger AR inhibition. Lonicerin (10), amentoflavone (27) and sophoraflavanone B (30) were also showed strong inhibitory activity. Especially, quercitrin and reyneutrin exhibited the most inhibitory potency on rat lens (RL) AR. The results suggested that flavonol having the 7-hydroxyl and/or catechol moiety at the B ring exhibit strong activity. In addition, flavonols having 3-O-monosaccharide also showed stronger inhibition than free flavonols at the 3-position. These results suggested that quercitrin and reyneutrin are attributed to be the promising compounds for the prevention and/or treatment of diabetic complications.