• Korean Journal of Pharmacognosy
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• v.33 no.4 s.131
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• pp.308-311
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• 2002

Advanced glycation end products(AGEs) are largly involved in the pathogenesis of diabetic nephropathy. It is obvious that inhibition of AGEs formation is important in preventing the occurrence and progression of diabetic nephropathy. In diabetes, this reaction is greatly accerated and is important in the pathogenesis of diabetic complications, especially diabetic nephropathy. Therefore, to seek possible AGEs inhibitors in herbal medicines, unprocessed - and processed Magnolia Bark were examined in vitro as basic data for aniaml experiment. The content of magnolol in unprocessed Magnolia Bark was $0.796{\pm}0.072%$, and after processing was decreased to $0.586{\pm}0.101%(p<0.01)$. The content of AGEs was measured by their intrinsic fluorescence. The $IC_{50}({\mu}g/ml)$ values of aminoguanidine, unprocessed- and procesled Magnolia Bark are $38.845{\pm}8.36{\mu}g/ml$, $54.264{\pm}3.153{\mu}g/ml$ and $27.882{\pm}1.836{\mu}g/ml$, respectively. This result means that prcessed Magnolia Bark was more effective than aminoguanidine, as positive control.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.2
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• pp.193-201
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• 2018

Connective tissue growth factor (CTGF) is a novel fibrotic mediator, which is considered to mediate fibrosis through extracellular matrix (ECM) synthesis in diabetic cardiovascular complications. Statins have significant immunomodulatory effects and reduce vascular injury. We therefore examined whether fluvastatin has anti-fibrotic effects in vascular smooth muscle cells (VSMCs) and elucidated its putative transduction signals. We show that advanced glycation end products (AGEs) stimulated CTGF mRNA and protein expression in a time-dependent manner. AGE-induced CTGF expression was mediated via ERK1/2, JNK, and Egr-1 pathways, but not p38; consequently, cell proliferation and migration and ECM accumulation were regulated by CTGF signaling pathway. AGE-stimulated VSMC proliferation, migration, and ECM accumulation were blocked by fluvastatin. However, the inhibitory effect of fluvastatin was restored by administration of CTGF recombinant protein. AGE-induced VSMC proliferation was dependent on cell cycle arrest, thereby increasing G1/G0 phase. Fluvastatin repressed cell cycle regulatory genes cyclin D1 and Cdk4 and augmented cyclin-dependent kinase inhibitors p27 and p21 in AGE-induced VSMCs. Taken together, fluvastatin suppressed AGE-induced VSMC proliferation, migration, and ECM accumulation by targeting CTGF signaling mechanism. These findings might be evidence for CTGF as a potential therapeutic target in diabetic vasculature complication.

• The Korea Journal of Herbology
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• v.32 no.3
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• pp.63-69
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• 2017

Objectives : Advanced glycation end product (AGEs) is combine formation of glucose and protein. AGEs and reactive oxygen species are potential therapeutic targets for the various disease such as diabetic complications, renal injury, skin damage. The aim of this study was investigated the AGEs inhibitory activity and antioxidant activity of water extracts from 40 Korean medicines and 5 heating-processed Korean medicines. Methods: AGEs formation inhibitory activities of Korean medicines measured using bovine serum albumin (BSA), glucose, and fructose. Then, five effective Korean medicines were selected and heated with 30% ethanol. The AGEs inhibitory activities of heated Korean medicine were measured compared with not-heated Korean medicines. The antioxidant activities were evaluated through radical scavenging assays using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals. Furthermore, we examined total phenol and flavonoids contents. Results: Scutellariae Radix, Corni Fructus, Persimmon Fruit, Paeoniae Radix, Mori Folium respectively reduced AGEs production. Morever, heating-processed Scutellariae Radix has AGEs inhibitory activities better than not-processed Scutellariae Radix. Heating- processed Scutellariae Radix scavenged DPPH and ABTS effectively and $IC_{50}$ of DPPH and ABTS radical scavenging activity of Heat processed Scutellariae Radix were $15.47{\pm}0.26{\mu}g/m{\ell}$ and $12.07{\pm}1.23{\mu}g/m{\ell}$. It caused heat processing methods of Scutellariae Radix up regulated total phenol and flavonoids contents ($26.68{\pm}0.01$ to $46.15{\pm}0.10$, $20.30{\pm}0.38$ to $64.20{\pm}0.52$). Conclusion: It has AGEs inhibitory activities that 20 kind of medicinal plants of 40 medicinal plants. Especially, heat processed Scutellariae Radix has excellent AGEs inhibitory activities and antioxidant effect.

• Journal of Applied Biological Chemistry
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• v.49 no.1
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• pp.24-27
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• 2006

Four ursane-type triterpenoids, 2${\alpha}$,3${\alpha}$,19${\alpha}$-trihydroxy-24-norurs-4(23),12-dien-28-oic acid (1), 4(R),23-epoxy-2${\alpha}$,3${\alpha}$,19${\alpha}$-trihydroxy-24-norurs-12-en-28-oic acid (2), myrianthic acid (3), and tormentic acid (4), and a phenolic compound, ethyl gallate (5), from an EtOAc-soluble extract of the stems of Rumex japonicus, were subjected to in vitro bioassays to evaluate advanced glycation end products (AGEs) and rat lens aldose reductase (RLAR) inhibitory activity. Compounds 1 and 5 exhibited a significant inhibitory activity on AGEs formation with $IC_{50}$ value of 87 ${\mu}M$ and on RLAR with $IC_{50}$ value of 14.3 ${\mu}M$, respectively. Ethyl gallate (5) was isolated for the first time from this plant.

• The Korea Journal of Herbology
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• v.32 no.4
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• pp.17-24
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• 2017

Objectives : Advanced glycation end products (AGEs) is bind formation of glucose and protein. Acceleration of AGE formation during hyperglycemia is associated with the pathogenesis of diabetic complications and causes kidney and skin damage. The aim of this study was investigated the AGEs inhibitory activity and antioxidant activity of water extracts from young persimmon (YP) and heated young persimmon (HYP). Methods : Paeoniae Radix Alba (YP) is prepared by heating with 30% ethanol. AGEs formation inhibitory activities of YP and HYP measured using bovine serum albumin. To evaluate the protective effects of YP and HYP in diabetic rats induced with streptozotocin (STZ) and methyl glyoxal (MGO), SD rats were distributed into four groups; normal mice (Nor), AGEs-induced rats (Con), AGEs-induced rats treated with 100 mg/kg YP (YP), AGEs-induced rats treated with 100 mg/kg heated YP (HYP) for 3weeks. Heated young persimmon respectively decrease AGEs construction. Results : YP and HYP administration inhibited the biomarkers of AGEs in serum, kidney and skin tissues. AGE-induced rats revealed that the significant decreased collagen however, heat processing methods of young persimmon up regulated inhibits AGEs-induced collagen decrease. The expressions of AGEs were decreased in YP and HYP treated group compared with the control group in tissues. It specifies that HYP has potential to serve as a positive regulator of via AGEs path way. Conclusion : It has proposed that may have an improvement effect on diabetic complications, heated young persimmon has AGEs inhibitory excellent activities and antioxidant effect.

• Korean Journal of Pharmacognosy
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• v.44 no.4
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• pp.372-378
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• 2013

In this study, the inhibitory effect on advanced glycation end products (AGEs) formation of 43 Korean herbal medicines has been evaluated. Among them, 16 Korean herbal medicines were showed to have significant effect ($IC_{50}$; <50 ${\mu}g/ml$) compared to positive reference, aminoguandine ($IC_{50}$: $76.47{\pm}4.81{\mu}g/ml$). Especially, five herbal medicines, Rubus coreanus (leaves, $IC_{50}$: $4.49{\pm}0.03{\mu}g/ml$), Rubus coreanus (twigs, $IC_{50}$: $3.80{\pm}0.34{\mu}g/ml$), Ampleopsis brevipedunculata (stems, $IC_{50}$: $7.43{\pm}0.09{\mu}g/ml$), Lindera erythrocarpa (leave, $IC_{50}$: $8.14{\pm}0.20{\mu}g/ml$), and Lindera erythrocarpa (stems, $IC_{50}$: $3.69{\pm}0.14{\mu}g/ml$) showed more potent inhibitory activity (approximately 9-20 fold) than the positive control aminoguanidine.

• Korean Journal of Pharmacognosy
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• v.39 no.3
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• pp.249-254
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• 2008

An 80% EtOH extract and the solvent fractions of the seeds of Cornus officinalis were evaluated for their inhibitory activities against advanced glycation end products (AGEs) formation and AGEs-induced protein cross-linking in vitro. In vitro assay for AGEs-bovine serum albumin (BSA) formation showed that the 80% EtOH extract, n-hexane, EtOAc, n-BuOH and water fractions significantly inhibited AGEs formation with observed $IC_{50}$ values of 1.13, 17.64, 1.52, 1.24 and $3.27{\mu}g/ml$, respectively. In indirect AGEs-ELISA assay, the 800% EtOH extract, EtOAc and n-BuOH fractions exhibited more potent inhibitory activity on AGEs-BSA formation than aminoguanidine, a well know AGEs inhibitor. Furthermore, the 80% EtOH extract and all the solvent fractions inhibited concentration-dependently AGE-BSA cross-linking to collagen. The 80% EtOH extract, EtOAc, n-BuOH and water fractions also had a breaking activity against preformed AGE-BSA cross-linking concentration dependently. Thus these results suggest that the 80% EtOH extract and fractions of the seeds of C. officinalis could be an inhibitor as well as breaker of AGE-BSA cross-linking.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.47 no.2
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• pp.147-153
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• 2021

Collagen hydrolysate (CH) is known to prevent skin aging by stimulating skin dermal fibroblasts to promote synthesis of extracellular matrix such as collagen and elastin. Recently, among the various factors that cause skin aging, advanced glycation end products (AGEs) have received particular attention. However, the effect of CH on AGE accumulation has not been studied. Since CH could affect AGE accumulation by promoting production of skin structural proteins, clinical trial was performed using low molecule collagen peptide (LMCP), which were CH containing 25% tripeptide and 4% Gly-Pro-Hyp. Skin autofluorescence (SAF) values were measured using an AGE reader to evaluate accumulation of AGE in skin. As a result of applying 0.5% and 1.0% LMCP solutions to the subject's forearm for 8 weeks, the SAF value at the test site significantly decreased compared to the control site. Additionally, in vitro test was performed using CCD-986sk to evaluate the promotion of collagen synthesis in skin fibroblasts by LMCP. As a result, 800 ㎍/mL of LMCP significantly increased synthesis of human pro-collagen Iα1 (COL1A1) in CCD-986sk. Through this study, we have confirmed that tropical LMCP applications can promote collagen synthesis to help anti-glycation effects, suggesting that LMCP has potential as an anti-aging cosmetic material.

• Korean Journal of Pharmacognosy
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• v.37 no.2 s.145
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• pp.103-109
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• 2006

Advanced glycation end products (AGEs) formation plays an important role in the progression of diabetic complications. To develop effective herbal formulations with suppression of diabetic nephropathy, a common complication in diabetic patients, we evaluated inhibitory activities of KIOM-79, a new herbal prescription, on the formation of AGEs using in vitro and in vivo model systems. Effects of KIOM-79 on the expression of AGEs, RAGEs (receptor for Advanced glycation end products), type IV collagen and renal $TGF-{\beta}1$ mRNA was also examined in streptozotocon (STZ)-induced diabetic rats. STZ-induced diabetic rats were treated orally with KIOM-79 (250 and $500\;kg^{-1}$ once a day for 13 weeks). In vitro system KIOM-79 suppressed the formation of AGEs $(18.12\;{\mu}g/ml)$. In STZ-induced diabetic rats showing accumulation of AGE and RAGE, pathological examination revealed that KIOM-79 prevented AGE and RAGE deposition in the kidney. In STZ induced diabetic rats, the expansion of mesangial matrix and the glomerular tufts seemed to be larger than those in normal rats. Howεver, after administration with KIOM-79, mesangial metrix and glomerular volume were decreased, and overexpression of type IV collagen was also decreased. Overexpression of renal $TGF-{\beta}1$ mRNA was inhibited significantly. These results suggest that the KIOM-79 might be an effective herbal prescription to prevent or alleviate the progression of diabetic nephropathy.

• The Korea Journal of Herbology
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• v.33 no.4
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• pp.95-100
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• 2018

Objectives : Ligustri Fructus has been used since ancient times as a medicinal usages in folk medicines against antitumor purpose. Many biological active constituents have been identified from this biomass such as several terpenoids and lignans. In current study, the properties of antioxidant and anti-diabetic complications using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)($ABTS^+$) radicals scavenging, and advanced glycation end products (AGEs) inhibition assays were evaluated by different extraction methods of Ligustri Fructus. Methods : In present continuing research for development of bioactive natural ingredients, antioxidant and AGEs formation inhibitory capacities of Ligustri Fructus extracts using different organic solvents were prepared and the biological potentials were investigated using in vitro bioassays. Antioxidant properties were evaluated employing radical scavenging assays using DPPH and $ABTS^+$ radicals. In addition, the anti-diabetic complications effects of Ligustri Fructus extracts were tested via AGEs formation inhibitory assay. The total phenolic contents were determined using a spectrophotometric method. Results : All the tested extracts exhibited dose-dependent radical scavenging and AGEs formation inhibitory activities. Among the tested samples, hot water extract of Ligustri Fructus was showed the most potent activity with $IC_{50}$ value of $494.8{\pm}6.7{\mu}g/m{\ell}$ against DPPH radical scavenging assay. Also, $ABTS^+$ radical scavenging activity of hot water extract was higher than those of other extracts. In addition, AGEs formation inhibitory effects of each extacts and total phenolic contents were evaluated. Conclusions : These results suggested that Ligustri Fructus can be considered as a new effective source of natural antioxidant and anti-diabetic complications resources.