• 생명과학회지
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• 제14권3호
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• pp.406-410
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• 2004

Glycation 반응은 glucose와 amino group 간에 일어나는 비효소적 축합 반응인 maillard 반응의 초기 반응으로 non enzymatic glycation 이라고도 한다. 생체내 glycation 반응을 통해 다수의 dicarbonyl화합물이 생성되고, 이들 dicarbonyl들 중에서 매우 반응성이 큰 것으로 확인된 glyoxal과 methylglyoxal과 catalase를 반응 시켜 glycation catalase의 활성 변화를 확인하였다. Non-glycated catalase에 비해 glycation catalase에서 구조적 인 modification과 degradation이 일어났으며, glycation반응 시간에 따라 활성이 크게 저하되는 것으로 확인 할 수 있었다. 특히 glycation 반응 시간 20일 경과 이후 glycation catalase 경우 활성이 거의 상실한 것으로 나타났다 Glyoxal과 methylglyoxal의 농도를 달리 해서 DNA와 반응 시켜 glycation propagator에 의한 직접적인 DNA damage를 확인 한 결과 Glyoxal과 methylglyoxal의 농도와 반응 시간에 따라 DNA mobility sit의 차이를 나타냈다. Fenton reaction 조건에 glyoxal과 methylglyoxal에 의해 활성이 저하된 catalase를 첨가 시켜 8-OH-dG의 생성을 확인한 결과 두 glycation propagator와의 반응 시간 의존적으로 8-OH-dG의 생성이 증가함을 보였다. 이상의 결과를 통해 glyoxal과 methylglyoxal의 antioxidant의 glycation은 oxidative stress의 증사를 유발해 생체내 활성 산소로부터 방어 기작에 심각한 문제를 야기하는 것으로 사료된다.

• Food Science and Biotechnology
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• 제15권4호
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• pp.603-605
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• 2006

Our previous study demonstrated that aqueous ethanolic extract of hardy rubber tree (HRT; Eucommia ulmoides Oliver) leaves potently inhibited glycation, and that two known flavonols and one new flavonol were the active compounds in protein glycation in vitro using the model system of bovine serum albumin and fructose. The aim of this study was to examine the effectiveness of HRT extract and its flavonols against the glycation of hemoglobin (Hb) in primary cultured rat erythrocytes. The extract at $40-400\;{\mu}g/mL$ and the flavonols at $0.2-20\;{\mu}g/mL$ significantly inhibited Hb glycation in a concentration-dependent manner. They were more effective than aminoguanidine, a well-known inhibitor of glycation. Three flavonols seemed to be responsible for the inhibitory activity of the extract, furthermore, the extract of HRT leaves showed advantages over single isolated flavonols in the inhibition of Hb glycation.

• 대한약리학회지
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• 제31권1호
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• pp.135-140
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• 1995

Glycation이란 단당류의 카보릴기와 아미노산의 입실론 아미노기가 공유결합에 의하여 형성되는 반응으로 이는 단백질의 생리적 기능을 변화시키며 아울러 당뇨합병증을 유발한다. 본 연구에서는 warfarin과 dansylsarcosine의 단백질결합에 미치는 glycation의 영향을 평형투석법을 이용하여 연구하였으며 평형투석은 섭씨 37도의 진탕수조에서 3시간 동안 실시하였다. 약물의 농도가 알부민의 농도보다 높을 경우, $50{\pm}16%$가 glycation된 알부민은 $8.5{\pm}5.28%$ glycation 알부민을 함유한 정상알부민에 비해 약물과의 결합도가 낮았으나 warfarin의 농도가 알부민의 3배가 될 경우에만 유의성이 인정되었고(P<0.05) 6%의 차이를 보였다. 본 실험에 나타난 glycation에 의한 유리약물의 미미한 상승효과는 glycated albumin 농도가 낮은 생체내의 여건과, 실제로 사용되는 약물의 적정 치료농도가 낮고 또한 과도한 유리약물은 신장을 통하여 신속히 배설되는 이유로 당뇨환자의 신기능 손상이 없는한 glycation에 의한 유리약물의 상승은 약물중독의 위험요소로 작용되지 않으리라 생각된다.

• Preventive Nutrition and Food Science
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• 제1권1호
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• pp.134-142
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• 1996

Diabetes carries an increased risk of atherosclerotic disease that is not fully explained by known car-diovascular risk factors. There is accumulating evidence that advanced glycation of structural proteins, and oxidation and glycation of circulating lipoproteins, are implicated in the pathogenesis of diabetic ather-osclerosis. Reactions involving glycation and oxidation of proteins and lipids are believed to contribute to atherogenesis. Glycation, the nonenzymatic binding of glucose to protein molecules, can increase the ather-ogenic potential of certain plasma constituents, including low density lipoptotein(LDL). Glycation of LDL is significant increased in diabetic patients compared with normal subjects, even in the presence of good glycemic control. Metabolic abnormalities associated with glycation of LDL include diminished recognition of LDL by the classic LDL receptor; increased covalent binding of LDL in vessel walls ; enhanced uptake of LDL by the macrophages, thus stimulating foam cell formation ; increased platelet aggregation; formation of LDL-immune complexes ; and generation of oxygen free radicals, resulting on oxidative damage to both the lipid and protein components of LDL and to any nearby macromolecules. Oxidized lipoproteins are characterzied by cytotoxicity, potent stimulation of foam cell formation by macrophages, and procoagulant effects. Combined glycation and oxidation, "glycoxidation" occurs when oxidative reactions affect the initial products of glycation, and results in irreversible structural alterations of proteins. Glycoxidation is of greatest significance in long lived proteins such as collagen. In these proteins, glycoxidation products, believed to be atherogenic, accumulate with advancing age : in diabetes, their rate of accumulate is accelerated. Inhibition of glycation, oxidation and glycoxidation may form the basis of future antiaterogenic strategies in both diabetic and nondiabetic individuals.dividuals.

• 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.

• 대한약침학회지
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• 제21권2호
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• pp.82-89
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• 2018

Objective: Diabetes mellitus (DM) is the most common metabolic disorder that defined by chronic hyperglycemia for the deficiency in insulin secretion or resistance. Hyperglycemia could induce non-enzymatic glycation of proteins. It has been suggested that some traditional plants can improve blood glucose and inhibit glycation process. This work evaluates and compares the anti-glycation activities of four Iranian plant extracts in vitro. Methods: The methanolic extract of "Fumaria officinalis, Stachys lavandulifolia, Salvia hydrangea and Rosa Damascene" was prepared in three different concentrations. Phenolic, flavonoids content and antioxidant activity were evaluated. The multistage glycation markers- fructosamines (early stage), protein carbonyls (intermediate stage) and ${\beta}$ aggregation of albumin were investigated in the bovine serum albumin (BSA)/ glucose systemt. Results: All plants showed the high potency of scavenging free radicals and glycation inhibition in the following order: Fumaria officinalis> Rosa Damascene> Stachys lavandulifolia > Salvia hydrangea. There was a significant correlation between antioxidant and anti-glycation activity. Also, the antioxidant and anti-glycation capacity of extracts correlated with total phenolic and flavonoids content. Conclusion: Our findings demonstrated that the studied plants are good sources of anti-glycation and antioxidant compounds and, these properties can primarily attributable to phenolics, particularly flavonoids.

• 분석과학
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• 제35권1호
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• pp.8-14
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• 2022

Many studies have shown that advanced glycation end-products (AGEs) and glycation adducts are significantly linked to aging and disease. Particularly, the level of glycation in human milk is important because the AGE intake is closely related to AGE levels in infants. In this study, we used human milk samples obtained from four primiparae and four multiparae. We isolated proteins using acetone and trichloroacetic acid (TCA) precipitation. A total of 67 glycated proteins and 122 glycated peptides was quantified; among them, 19 glycated peptides were differentially expressed. We confirmed that the degree of glycation differed according to fertility. The study provides a foundation for using proteomics to evaluate the mother's milk quality and link between maternal health and human milk quality.

• 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.

• 대한화장품학회지
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• 제43권3호
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• pp.239-245
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• 2017

노화는 생리학적으로 비가역적으로 일어나는 과정으로 노화가 진행됨에 따라 단백질의 산화화학반응 등으로 노화징후가 축적된다. 활성산소와 당화된 최종 당화산물(advanced glycation endproducts, AGEs 최종 당화산물)은 생체 조직과 세포를 공격하여 노화를 촉진한다고 알려져 있다. 본 연구에서는 항산화 물질로 알려진 aminoguanidine을 양성 대조군으로 anti-glycation 효과를 확인하였으며, methoxy PEG-45 thioctate(LA-PEG)를 농도별로 처리하여 anti-glycation 효과를 평가하였다. 실험결과 LA-PEG는 매우 우수한 anti-glycation 효과로 최종 당화산물(AGEs) 생성억제 활성이 매우 우수하게 나타났으며, 항산화 효과와 밀접한 연관을 나타냈다. 또, 세포노화 지표물질인 senescence-associated ${\beta}$-galactosidase ($SA-{\beta}-gal$) 활성을 사람 섬유아세포(HDF)를 이용하여 확인한 결과, LA-PEG를 처리하였을 때 염색된 세포의 수가 감소하여 세포의 senescence를 억제하는 것을 확인할 수 있었다. 본 연구결과, LA-PEG의 anti-glycation 효과 및 산화로 인한 단백질 손상에 대한 보호 효과가 우수하게 나타났으며, 항노화 화장품에 적용 시 효과적으로 적용할 수 있을 것으로 사료된다.

• 한국식품저장유통학회지
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• 제24권4호
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• pp.536-541
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• 2017

Hyperglycemia found in diabetes mellitus causes several physiological abnormalities including the formation of advanced glycation end products (AGEs) and oxidative stress. Accumulation of AGEs and elevation of oxidative stress plays major roles in the development of diabetic complications. Adiponectin secreted from adipocytes is known to improve insulin sensitivity and blood glucose level. Curcumin (CCM), a bioactive component of turmeric, has been reported as a potent antioxidant. Present work aimed to elucidate the roles of CCM in high glucose-induced protein glycation and intracellular events in mature adipocytes. The results demonstrated that CCM inhibited the formation of fluorescent AGEs by approximated 52% at 3 weeks of bovine serum albumin (BSA) glycation with glucose. Correspondingly, CCM decreased the levels of fructosamine and ${\alpha}-dicarbonyl$ compounds during BSA glycation with glucose. These data suggested that CCM might be a new promising anti-glycation agent. Also, CCM reduced high glucose-induced oxidative stress in a dose dependent manner, whereas CCM treatment time-dependently elevated the expression of adiponectin gene in 3T3-L1 adipocytes. The findings from this study suggested the possibility of therapeutic use of CCM for the prevention of diabetic complications and obesity-related diseases.