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Glycation ascorbic acid and AGEs

Seung Hwan Hwang, Zhiqiang Wang, Soon Sung Lim
This study successfully established the feasibility of a two-step chemo-enzymatic synthesis of l-ascorbyl phenolates. Intermediate vinyl phenolates were first chemically produced and then underwent trans-esterification with l-ascorbic acid in the presence of Novozyme 435® (Candida Antarctica lipase B) as a catalyst. Twenty vinyl phenolates and 11 ascorbyl phenolates were subjected to in vitro bioassays to investigate their inhibitory activity against advanced glycation end products (AGEs). Among them, vinyl 4-hydroxycinnamate (17VP), vinyl 4-hydroxy-3-methoxycinnamate (18VP), vinyl 4-hydroxy-3,5-dimethoxycinnamate (20VP), ascorbyl 4-hydroxy-3-methoxycinnamate (18AP) and ascorbyl 3,4-dimethoxycinnamate (19AP) showed 2-10 times stronger inhibitory activities than positive control (aminoguanidine and its precursors)...
January 1, 2017: Food Chemistry
Chamira Dilanka Fernando, Diyathi Tharindhi Karunaratne, Sachith Dilshan Gunasinghe, M C Dilusha Cooray, Prabuddhi Kanchana, Chandani Udawatte, Pathirage Kamal Perera
BACKGROUND: Advanced glycation end products (AGEs) and free radicals are inflammatory mediators and are implicated in many diseases such as diabetes, cancer, rheumatoid arthritis etc. Multi targeted poly herbal drug systems like Nawarathne Kalka (NK) are able to quench the overall effect of these mediators as they contain good combinations of phytochemicals that have least side effects in contrast to modern medicinal drugs. The objectives of this study were to evaluate phytochemical composition, free radical scavenging activity, cytotoxicity and the inhibitory action on the formation of AGEs by aqueous extract of NK...
2016: BMC Complementary and Alternative Medicine
Antonio Dario Troise, Daniele Vitiello, Catherine Tsang, Alberto Fiore
The presence of amino groups and carbonyls renders fortified milk with ascorbic acid particularly susceptible to the reduction of available lysine and to the formation of Maillard reaction products (MRPs), as Nε-(carboxyethyl)-l-lysine (CEL), Nε-(carboxymethyl)-l-lysine (CML), Amadori products (APs) and off-flavors. A novel approach was proposed to control the Maillard reaction (MR) in fortified milk: ascorbic acid was encapsulated in a lipid coating and the effects were tested after a lab scale UHT treatment...
June 15, 2016: Food & Function
Ganeshan Shakambari, Balasubramaniem Ashokkumar, Perumal Varalakshmi
Advanced Glycation End products (AGE) generated in a non enzymatic protein glycation process are frequently associated with diabetes, aging and other chronic diseases. Here, we explored the protective effect of phlorotannins from brown algae Padina pavonica, Sargassum polycystum and Turbinaria ornata against AGEs formation. Phlorotannins were extracted from brown algae with methanol and its purity was analyzed by TLC and RP-HPLC-DAD. Twenty five grams of P. pavonica, S. polycystum, T. ornata yielded 27.6 ± 0...
June 2015: Indian Journal of Experimental Biology
Tanyawan Suantawee, Krittaporn Wesarachanon, Kanokphat Anantsuphasak, Tanuch Daenphetploy, Sroshin Thien-Ngern, Thavaree Thilavech, Porntip Pasukamonset, Sathaporn Ngamukote, Sirichai Adisakwattana
Syzygium aromaticum (L.) (clove) is one of the most widely cultivated spices in many tropical countries. The aim of this study was to determine the phytochemical content, the antioxidant properties and the antiglycation properties of aqueous extract of clove against fructose-mediated protein glycation and oxidation. The result showed that the content of total phenolics and flavonoids in clove extract was 239.58 ± 0.70 mg gallic acid equivalents/g dried extract and 65.67 ± 0.01 mg catechin equivalents/g dried extract, respectively...
June 2015: Journal of Food Science and Technology
Benedetto Marelli, Damien Le Nihouannen, S Adam Hacking, Simon Tran, Jingjing Li, Monzur Murshed, Charles J Doillon, Chiara E Ghezzi, Yu Ling Zhang, Showan N Nazhat, Jake E Barralet
Copper is becoming recognised as a key cation in a variety of biological processes. Copper chelation has been studied as a potential anti-angiogenic strategy for arresting tumour growth. Conversely the delivery of copper ions and complexes in vivo can elicit a pro-angiogenic effect. Previously we unexpectedly found that copper-stimulated intraperitoneal angiogenesis was accompanied by collagen deposition. Here, in hard tissue, not only was healing accelerated by copper, but again enhanced deposition of collagen was detected at 2 weeks...
June 2015: Biomaterials
Yingdong Zhu, Yantao Zhao, Pei Wang, Mohamed Ahmedna, Chi-Tang Ho, Shengmin Sang
Growing evidence has shown that ascorbic acid (ASA) can contribute to protein glycation and the formation of advanced glycation end products (AGEs), especially in the lens. The mechanism by which ascorbic acid can cause protein glycation probably originates from its oxidized form, dehydroascorbic acid (DASA), which is a reactive dicarbonyl species. In the present study, we demonstrated for the first time that four tea flavanols, (-)-epigallocatechin 3-O-gallate (EGCG), (-)-epigallocatechin (EGC), (-)-epicatechin 3-O-gallate (ECG), and (-)-epicatechin (EC), could significantly trap DASA and consequently form 6C- or 8C-ascorbyl conjugates...
January 20, 2015: Chemical Research in Toxicology
Christian Henning, Kristin Liehr, Matthias Girndt, Christof Ulrich, Marcus A Glomb
Maillard α-dicarbonyl compounds are known as central intermediates in advanced glycation end product (AGE) formation. Glucose is the primary source of energy for the human body, whereas l-threo-ascorbic acid (vitamin C) is an essential nutrient, involved in a variety of enzymatic reactions. Thus, the Maillard degradation of glucose and ascorbic acid is of major importance in vivo. To understand the complex mechanistic pathways of AGE formation, it is crucial to extend the knowledge on plasma concentrations of reactive key α-dicarbonyl compounds (e...
October 10, 2014: Journal of Biological Chemistry
Bharathinagar S Suresha, Krishnapura Srinivasan
Elevated polyol pathway enzyme activities and oxidative stress play an important role in the development and progression of diabetic nephropathy. Here, we investigated the beneficial influence of nigerloxin, a fungal metabolite and a potent aldose reductase inhibitor and free radical scavenger in the kidney of streptozotocin-induced diabetic rats. A group of diabetic rats was orally administered with nigerloxin for 30 days (100 mg/kg). Diabetic rats showed increased lipid peroxides, advanced glycation end products (AGEs), elevated activities of polyol pathway enzymes, and lowered antioxidant defense system in kidney...
September 2014: Naunyn-Schmiedeberg's Archives of Pharmacology
Mikhail Linetsky, Cibin T Raghavan, Kaid Johar, Xingjun Fan, Vincent M Monnier, Abhay R Vasavada, Ram H Nagaraj
Advanced glycation end products (AGEs) contribute to lens protein pigmentation and cross-linking during aging and cataract formation. In vitro experiments have shown that ascorbate (ASC) oxidation products can form AGEs in proteins. However, the mechanisms of ASC oxidation and AGE formation in the human lens are poorly understood. Kynurenines are tryptophan oxidation products produced from the indoleamine 2,3-dioxygenase (IDO)-mediated kynurenine pathway and are present in the human lens. This study investigated the ability of UVA light-excited kynurenines to photooxidize ASC and to form AGEs in lens proteins...
June 13, 2014: Journal of Biological Chemistry
Ji-Young Lee, Jun-Gu Oh, Jin Sook Kim, Kwang-Won Lee
Advanced glycation end-products (AGEs) have been implicated in the development of diabetic complications. We report the antiglycating activity of chebulic acid (CA), isolated from Terminalia chebula on breaking the cross-links of proteins induced by AGEs and inhibiting the formation of AGEs. Aminoguanidine (AG) reduced 50% of glycated bovine serum albumin (BSA) with glycolaldehyde (glycol-BSA)-induced cross-links of collagen at a concentration of 67.8 ± 2.5 mM, the level of CA required for exerting a similar antiglycating activity was 38...
2014: Biological & Pharmaceutical Bulletin
Andrej Frolov, Rico Schmidt, Sandro Spiller, Uta Greifenhagen, Ralf Hoffmann
Glycation refers to the reaction of amino groups, for example in proteins, with reducing sugars. Intermediately formed Amadori products can be degraded by oxidation (Maillard reactions) leading to a heterogeneous class of advanced glycation end-products (AGEs), especially during exposure to heat. AGEs are considered to be toxic in vivo due to their pronounced local and systemic inflammatory effects. At high temperatures, these reactions have been mostly investigated at the amino acid level. Here, we studied the formation of arginine-related AGEs in peptides under conditions simulating household cooking at physiological d-glucose concentrations...
April 23, 2014: Journal of Agricultural and Food Chemistry
Zoe Diana Draelos
The role of diet in aging skin is highly controversial with limited available scientific data. There are recommended daily allowances for vitamins and other essential nutrients necessary for the maintenance of health, but these allowances were arrived at by consensus rather than science. These nutritional allowances are set at the minimum required for health, providing little advice as to the optimal nutritional intake for a given age. We now know that the requirements set for vitamin D intake were too low and not properly age adjusted...
November 2013: Clinics in Dermatology
Silvia Isabel Rech Franke, Luiza Louzada Müller, Maria Carolina Santos, Arcênio Fishborn, Liziane Hermes, Patrícia Molz, Camila Schreiner Pereira, Francisca Maria Assmann Wichmann, Jorge André Horta, Sharbel Weidner Maluf, Daniel Prá
Hyperglycemia leads to the formation of free radicals and advanced glycation end-products (AGEs). Antioxidants can reduce the level of protein glycation and DNA damage. In this study, we compared the levels of vitamin C intake, which is among the most abundant antioxidants obtained from diet, with the levels of fasting plasma glucose (FPG), glycated hemoglobin (A1C), DNA damage, and cytotoxicity in prediabetic subjects and type 2 diabetic subjects. Our results indicated that there was no significant correlation between FPG or A1C and DNA damage parameters (micronuclei, nucleoplasmic bridges, and nuclear buds)...
2013: BioMed Research International
Vincent M Monnier, Wanjie Sun, David R Sell, Xingjun Fan, Ina Nemet, Saul Genuth
Advanced glycation end products (AGEs) represent a family of protein, peptide, amino acid, nucleic acid and lipid adducts formed by the reaction of carbonyl compounds derived directly or indirectly from glucose, ascorbic acid and other metabolites such as methylglyoxal. AGE formation in diabetes is of growing importance for their role as markers and potential culprits of diabetic complications, in particular retinopathy, nephropathy and neuropathy. Development of sensitive and specific assays utilizing liquid chromatography mass spectrometry with isotope dilution method has made it possible to detect and quantitate non-UV active AGEs such as carboxymethyl-lysine and glucosepane, the most prevalent AGE and protein crosslink of the extracellular matrix...
January 1, 2014: Clinical Chemistry and Laboratory Medicine: CCLM
Natália Kamodyová, L'ubomíra Tóthová, Peter Celec
BACKGROUND: Salivary markers of oxidative stress and antioxidant status represent promising tool for the research of oral diseases. One of the criteria is the validation of these biomarkers from the perspective of the confounding and modifying factors. AIM: To examine the effect of circadian rhythm, tooth-brushing and ascorbic acid treatment on selected salivary markers of oxidative and carbonyl stress, and antioxidant status. SUBJECTS AND METHODS: Whole unstimulated saliva samples were collected from 19 healthy participants three times during a day, before and after tooth-brushing, and before and after the administration of vitamin C (250 mg)...
2013: Disease Markers
Mareen Smuda, Marcus A Glomb
The Maillard reaction network with focus on the chemistry of dicarbonyl structures causes considerable interest of research groups in food chemistry and medical science, respectively. Dicarbonyl compounds are well established as the central intermediates in the nonenzymatic browning reaction and have been verified to be responsible for advanced glycation endproduct (AGE) formation. A multitude of Maillard dicarbonyls covering the range of the intact carbon backbone down to C3 and C2 fragments were detected in several carbohydrate systems, for example, in glucose, maltose, or ascorbic acid reactions...
October 30, 2013: Journal of Agricultural and Food Chemistry
Elena Fitzenberger, Michael Boll, Uwe Wenzel
Hyperglycemia is a hallmark of diabetes that is associated with diabetic complications and a reduction of lifespan. Using the mev-1 mutant of the nematode Caenorhabditis elegans we here tried to identify molecular mechanisms underlying the lifespan reducing effects of glucose. The lowest glucose concentration tested (10mM) caused a significant lifespan reduction at 37°C and was used to assess effects on mitochondrial efficiency, formation of protein carbonyls and levels of methylglyoxal, a precursor of advanced glycation end products (AGEs)...
April 2013: Biochimica et Biophysica Acta
Lin Li, Lipeng Han, Quanyi Fu, Yuting Li, Zhili Liang, Jianyu Su, Bing Li
N(ε)-(carboxymethyl) lysine (CML) is the most abundant advanced glycation end product (AGE), and frequently selected as an AGEs marker in laboratory studies. In this paper, the formation and inhibition of N(ε)-(carboxymethyl)lysine in saccharide-lysine model systems during microwave heating have been studied. The microwave heating treatment significantly promoted the formation of CML during Maillard reactions, which was related to the reaction temperature, time and type of saccharide. The order of CML formation for different saccharides was lactose > glucose > sucrose...
2012: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Fawzi M Mahomoodally, Anwar H Subratty, Ameenah Gurib-Fakim, Muhammad Iqbal Choudhary
BACKGROUND: Many indigenous plants of Mascarene Islands have been used in folkloric medicine to manage diabetes but few species have received scientific attention. Selected traditional medicinal plants (Antidesma madagascariense Lam. -Euphorbiaceae (AM), Erythroxylum macrocarpum O.E.Schulz -Erythroxylaceae (EM), Pittosporum senacia Putterl -Pittosporaceae (PS), Faujasiopsis flexuosa Lam. C.Jeffrey -Asteraceae (FF), Momordica charantia Linn -Cucurbitaceae (MC) and Ocimum tenuiflorum L -Lamiaceae (OT) were evaluated for their antioxidant, antiglycation and cytotoxic potential in vitro...
2012: BMC Complementary and Alternative Medicine
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