• The Korean Journal of Physiology and Pharmacology
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• 제18권1호
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• pp.1-14
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• 2014

During long standing hyperglycaemic state in diabetes mellitus, glucose forms covalent adducts with the plasma proteins through a non-enzymatic process known as glycation. Protein glycation and formation of advanced glycation end products (AGEs) play an important role in the pathogenesis of diabetic complications like retinopathy, nephropathy, neuropathy, cardiomyopathy along with some other diseases such as rheumatoid arthritis, osteoporosis and aging. Glycation of proteins interferes with their normal functions by disrupting molecular conformation, altering enzymatic activity, and interfering with receptor functioning. AGEs form intra- and extracellular cross linking not only with proteins, but with some other endogenous key molecules including lipids and nucleic acids to contribute in the development of diabetic complications. Recent studies suggest that AGEs interact with plasma membrane localized receptors for AGEs (RAGE) to alter intracellular signaling, gene expression, release of pro-inflammatory molecules and free radicals. The present review discusses the glycation of plasma proteins such as albumin, fibrinogen, globulins and collagen to form different types of AGEs. Furthermore, the role of AGEs in the pathogenesis of diabetic complications including retinopathy, cataract, neuropathy, nephropathy and cardiomyopathy is also discussed.

• 생약학회지
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• 제37권1호통권144호
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• pp.48-52
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• 2006

Advanced glycation end products (AGEs) are largely involved in the pathogenesis of diabetic complications. As part of our ongoing project directed toward the discovery of preventive and/or delay agents for diabetic complications from natural sources, 92 Korean traditional herbal medicines have been investigated with an in vitro evaluation system using AGEs inhibitory activity. Of these, 17 herbal medicines exhibited a significant inhibitory activity against AGEs formation. Particularly, 9 herbal medicines, i.e., Cinnamomi Cortex, Artemisiae Argyi Herba, Ammoni Tsao-ko Fructus, Menthae Herba, Amomi Semen, Polygoni Avicularis Herba, Lycopi Herba, Salviae Radix, and Nelumbinis Semen showed more potent inhibitory activity (2-4 fold) than the positive control aminoguanidine.

• Natural Product Sciences
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• 제14권3호
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• pp.192-195
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• 2008

Three known compounds, puerarol (1), pueroside B (2), and ononin (3), were isolated from an EtOAc-soluble fraction of the roots of Pueraria lobata. The isolates (1 - 3) were subjected to an in vitro bioassay to evaluate their inhibitory activity on the formation of advanced glycation end products (AGEs). Puerarol (1) exhibited a remarkable inhibitory activity on AGEs formation with $IC_{50}$ value of $2.05{\pm}0.32{\mu}M$ as compared with positive control, aminoguanidine ($IC_{50}$ value : $905.32{\pm}7.58{\mu}M$).

• Archives of Pharmacal Research
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• 제29권7호
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• pp.587-590
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• 2006

Three naphthopyrone glucosides, cassiaside (1), $rubrofusarin-6-O-{\beta}-D-gentiobioside$ (2), and $toralactone-9-O-{\beta}-D-gentiobioside$ (3), were isolated from the BuOH-soluble extract of the seeds of Cassia tora as active constituents, using an in vitro bioassay based on the inhibition of advanced glycation end products (AGEs) to monitor chromatographic fractionation. The structures of 1-3 were determined by spectroscopic data interpretation, particularly by extensive 1D and 2D NMR studies. All the isolates (1-3) were evaluated for the inhibitory activity on AGEs formation in vitro.

• Journal of Nutrition and Health
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• 제49권4호
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• pp.233-240
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• 2016

항산화, 항암 및 항염증 효능 등의 생리 활성이 보고된 우엉 뿌리의 열수 추출물을 제조하여 advanced glycation end products (AGEs) 형성 저해 효과를 확인하였다. AGEs는 bovine serum albumin (BSA)과 단당류인 glucose, fructose, galactose를 혼합하여 $37^{\circ}C$에서 3주간 배양하여 생성하였고 매주 형광도 측정, fructosamine 분석, ${\alpha}$-dicarbonyl compounds 함량 분석을 통해 AGEs의 생성량을 확인하였다. 우엉 뿌리 추출물의 AGEs 생성 저해능을 AGEs 생성 억제제로 알려져 있는 aminoguanidine (AG)의 저해능과 비교하였다. 우엉 뿌리 추출물은 BSA와 단당류인 glucose, fructose, galactose 각각의 당화반응을 억제하였으며 특히 배양 3주차에서 BSA와 glucose의 당화반응 결과물인 AGEs 생성을 유의적으로 저해하였다. 농도 2 mg/mL 이상의 우엉 뿌리 추출물은 1 mM AG보다 AGEs 생성 저해능이 우수하였으며 농도 4 mg/mL의 우엉 뿌리 추출물은 배양 3주차에서 AGEs 생성을 약 80% 이상 억제하는 효능을 나타냈다. 체내 혈당은 당뇨병과 같은 질환과 식이의 영향을 받으므로 다양한 glucose 농도에서 우엉 뿌리 추출물의 AGEs 생성 억제능을 조사하였다. 그 결과 AGEs 생성은 glucose의 농도에 비례하여 증가하였으며 우엉 뿌리 추출물은 당뇨환자의 식후에 관찰되는 혈당인 25 mM glucose 군에서 1 mM의 AG보다 높은 우수한 저해 효과를 확인하였다. 본 연구 결과는 우엉 뿌리 추출물의 AGEs 생성 억제라는 새로운 기능성을 밝히며 향후 당뇨 합병증 예방 효능을 가진 기능성 식품으로의 개발 가능성을 제시한다.

• 생약학회지
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• 제37권4호
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• pp.307-313
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• 2006

Reactive oxygen species (ROS) and formation of advanced glycation end products (AGEs) play an important role in the pathogenesis of diabetic nephropathy by hyperglycemia. To find natural agents improving diabetic nephropathy, 63 natural resources which used to the treatment of diabetes mellitus in a folk remedy were investigated with an in vitro system employing radical scavenging activity and inhibitory activity of AGEs formation. In results, the extracts of Aspalathus linearis, Rubus coreanus, Rosa rugosa, and Epimedium koreanum significantly inhibited the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical with $IC_{50}$ values less than $10{\mu}g/ml$. The extracts of Zea mays, Cucurbita moschata, Cudrania tricuspidata, and Aspalathus linearis effectively reduced the formation of AGEs compared with the positive control $N-acetyl-_L-cystenine$ (NAC) and aminoguanidine (AG). In addition, the extracts of Aspalathus linearis, Commelina communis, Cornus officinalis, and Lespodeza cuneata showed the all inhibitory activity against DPPH radical and AGEs formation. Also, these resources definitely showed the radical scavenging activity against peroxynitrite $(ONOO^-)$ and hydroxyl radical $({\cdot}OH)$ relating to high glucose-induced ROS production. Thus, these results suggest that some natural resources may regulate the initiation and progression of diabetic nephropathy through inhibition of ROS production and AGEs formation.

• 생약학회지
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• 제40권4호
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• pp.388-393
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• 2009

Advanced glycation end products (AGEs) have been implicated in the development of diabetic complications. The AGEs inhibitors or cross-link breakers attenuate various functional and structural manifestations of diabetic complications. In this study, 64 herbal medicines from China and Vietnam have been investigated with an in vitro evaluation system using AGEs inhibitory activity. Of these, eight herbal medicines ($IC_{50}$<50 ${\mu}g$/ml) were found to have strong AGEs inhibitory activity compared with aminoguanidine (14 days, $IC_{50}$=75.98 ${\mu}g$/ml; 28 days, $IC_{50}$=88.27 ${\mu}g$/ml). Particularly, four herbal medicines, Buddleja officinalis (whole plant), Syzygium cuminii (leaf), Eugenia caryophyllate (seed), and Paeonia suffruticosa (root) showed more potent inhibitory activity (approximately 5-6 fold) than the positive control aminoguanidine.

• 생약학회지
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• 제42권1호
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• pp.46-53
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• 2011

Advanced glycation end products (AGEs) have been postulated to play a central role in the development of diabetic complications. A variety of different agents that inhibit AGEs have been under investigation. In this study, 66 herbal medicines from China have been investigated with an in vitro evaluation system using AGEs formation inhibitory activity. Of these, 31 herbal medicines ($IC_{50}$ < $50\;{\mu}g/ml$) were found to have significant AGEs formation inhibitory activity. Particularly, 5 herbal medicines, Camptotheca acuminata (branches and leaves), Quercus franchetii (branches), Camellia pitardii (leaves, branches, and fruits), Antidesma bunius (whole plants), and Loranthus parasiticus (whole plants) showed more potent inhibitory activity (approximately 6-20 fold) than the positive control aminoguanidine ($IC_{50}=52.96\;{\mu}g/ml$).

• 생약학회지
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• 제44권3호
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• pp.305-311
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• 2013

Advanced glycation end products (AGEs) have been postulated to play a central role in the development of diabetic complications. A variety of different agents that inhibit AGEs have been under investigation. In this study, 54 herbal medicines from China have been investigated with an in vitro evaluation system using AGEs formation inhibitory activity. Of these, 6 herbal medicines ($IC_{50}&lt;5{\mu}g/ml$) were found to have significant AGEs formation inhibitory activity. Particularly, herbal medicines Punica granatum (peels), Terminalia chebula (fruits), Rheum palmatum (roots), Oxyria digyna (stems and leaves), Anisodus luridus (roots) and Quercus schottkyana(stems and leaves) showed more potent inhibitory activity (approximately 9-43 fold) than the positive control aminoguanidine ($IC_{50}=77.04{\mu}g/ml$).

• 생약학회지
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• 제46권3호
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• pp.260-267
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• 2015

Advanced glycation end products (AGEs) have been postulated to play a central role in the development of diabetic complications. A variety of different agents that inhibit AGEs have been under investigation. In this study, 111 herbal medicines from China have been investigated with an in vitro evaluation system using AGEs formation inhibitory activity. Of these, 9 herbal medicines (IC₅₀: <5 μg/ml) were found to have significant AGEs formation inhibitory activity. Particularly, herbal medicines Barleria cristata (leaves), Calotropis gigantea (stems), Ardisia virens (leaves), Dalbergia yunnanensis (leaves) Pittosporum runcatum (leaves), Ardisia japonica (leaves), Rhododendron racemosum (twigs), Oxyria sinensiss (aerial parts), Pyrrosia calvata (whole plants), showed more potent inhibitory activity (approximately 15-40 fold) than the positive control aminoguanidine (IC₅₀: 76.47 μg/ml).