Succination is a non-enzymatic post-translational modification of cysteine (Cys) residues, resulting in the formation of -(2-succino)cysteine (2SC). While hundreds of 2SC-modified proteins have been identified and are associated with the dysfunction of proteins, the underlying molecular mechanisms remain poorly understood. Conventional methods for synthesizing succinated compounds, such as 2SC, often require prolonged reaction times and/or HCl hydrolysis.
View Article and Find Full Text PDFAdvanced glycation end-products (AGEs) have been extensively studied because of their close association with the onset and progression of diabetic complications. However, owing to their formation through diverse metabolic pathways, AGEs often reflect a wide range of pathological conditions rather than being specific to diabetic complications. Consequently, identifying an AGE that directly correlates only with diabetic complications remains a challenge.
View Article and Find Full Text PDF-(Carboxymethyl)lysine (CML) is a major advanced glycation end-product (AGE) involved in protein dysfunction and inflammation . Its accumulation increases with age and is enhanced with the pathogenesis of diabetic complications. Therefore, the pathways involved in CML formation should be elucidated to understand the pathological conditions involved in CML.
View Article and Find Full Text PDFAdvanced glycation end-products (AGEs) formation increases with metabolic disorders, leading to higher serum AGE levels in patients with progressive vascular complications. Measuring AGE levels in biological samples requires multiple pre-analytical processing steps, rendering analysis of multiple samples challenging. This study evaluated the progression of diabetic complications by analyzing AGE levels using a pre-analytical processing strategy based on a fully automated solid phase-extraction system.
View Article and Find Full Text PDFAs inhibitors of advanced glycation end products (AGEs), such as pyridoxamine, significantly inhibit the development of retinopathy and neuropathy in rats with streptozotocin-induced diabetes, treatment with AGE inhibitors is believed to be a potential strategy for the prevention of aging, age-related diseases, and lifestyle-related diseases, including diabetic complications. In the present study, the MeOH extract of (EH; aerial parts of spp.) was found to inhibit the formation of -(carboxymethyl)lysine (CML) and -(carboxymethyl) arginine (CMA) during the incubation of collagen-derived gelatin with ribose.
View Article and Find Full Text PDFGlucoselysine (GL) is an unique advanced glycation end-product derived from fructose. The main source of fructose in vivo is the polyol pathway, and an increase in its activity leads to diabetic complications. Here, we aimed to demonstrate that GL can serve as an indicator of the polyol pathway activity.
View Article and Find Full Text PDFPentosidine (PEN) is an advanced glycation end-product (AGEs), where a fluorescent cross-link is formed between lysine and arginine residues in proteins. Accumulation of PEN is associated with aging and various diseases. We previously reported that a subpopulation of patients with schizophrenia showed PEN accumulation in the blood, having severe clinical features.
View Article and Find Full Text PDFMitochondrial stress increases the production of fumarate, an intermediate of the Krebs cycle. Fumarate non-enzymatically reacts with the thiol group of cysteine, leading to the production of -(2-succinyl)cysteine. Here, we quantified the concentration of fumarate, the free form of -(2-succinyl)cysteine, and advanced glycation end-products, including -(carboxymethyl)lysine and -(5-hydro-5-methyl-4-imidazolone-2-yl)-ornithine, in the serum of chronic kidney disease patients, using liquid chromatography-tandem mass spectrometry and an enzymatic assay.
View Article and Find Full Text PDFBackground: In recent years, immune checkpoint inhibitors (ICI) have been often used for several types of cancers. Immune-related adverse events (irAEs) are autoimmune responses caused by ICI. Among the different types of irAEs, uveitis is common in ophthalmology.
View Article and Find Full Text PDFIt is suggested that activation of receptor for advanced glycation end products (RAGE) induces proinflammatory response in diabetic nerve tissues. Macrophage infiltration is invoked in the pathogenesis of diabetic polyneuropathy (DPN), while the association between macrophage and RAGE activation and the downstream effects of macrophages remain to be fully clarified in DPN. This study explored the role of RAGE in the pathogenesis of DPN through the modified macrophages.
View Article and Find Full Text PDFAdvanced glycation end products (AGEs), produced by the Maillard reaction between carbohydrates and proteins, may be involved in diabetes and its complications. Accurate quantification of AGEs can demonstrate the relation between AGEs and pathological conditions, but it is not widely used in clinical practice because of the multiple pretreatment steps before analyses. We developed a fully automated solid-phase extraction system (FSPES) to simplify rate-limiting pretreatment using a cation exchange column.
View Article and Find Full Text PDFReducing sugars can covalently react with proteins to generate a heterogeneous and complex group of compounds called advanced glycation end products (AGEs). AGEs are generally considered as pathogenic molecules, mediating a pro-inflammatory response and contributing to the development of a number of human diseases. However, the intrinsic function of AGEs remains to be elucidated.
View Article and Find Full Text PDFCysteine is non-enzymatically modified by fumarate, which is an intermediate of the tricarboxylic acid cycle, leading to the formation of S-(2-succinyl)cysteine (2SC). Post-translational modification of physiological proteins by fumarate causes enzyme dysfunction. The aim of the study was to evaluate the changes in 2SC accumulation in physiological tissues associated with aging.
View Article and Find Full Text PDFAdvanced glycation end products (AGEs) are associated with diabetes and its complications. AGEs are formed by the non-enzymatic reactions of proteins and reducing sugars, such as glucose and ribose. Ribose is widely used in glycation research as it generates AGEs more rapidly than glucose.
View Article and Find Full Text PDFAdvanced glycation end-products (AGEs) are formed when proteins react with carbonyl compounds, and they gradually accumulate with age. However, AGE accumulation with ageing is not fully understood because longevity studies in mammals are time-consuming. Therefore, we used Caenorhabditis elegans to evaluate the correlation between ageing and AGE accumulation.
View Article and Find Full Text PDFMethylglyoxal (MGO) produced during glycolysis is known to react with arginine residues on proteins to generate advanced glycation end products, such as N-(5-hydro-5-methyl-4-imidazolone-2-yl)-ornithine (MG-H1). Since the production of MGO is increased during hyperglycemia or metabolic disorders in vivo, it is considered that the measurement of MG-H1 is useful for evaluating abnormalities in carbohydrate metabolism. Thus, we prepared a monoclonal antibody against MG-H1 to develop a conventional measurement system for MG-H1.
View Article and Find Full Text PDFAdvanced glycation end-products (AGEs) deteriorate bone strength. Among over 40 species identified in vivo, AGEs other than pentosidine were roughly estimated as total fluorescent AGEs (tfAGEs) due to technical difficulties. Using LC-QqTOF-MS, we established a system that enabled the quantitation of five AGEs (CML, CEL, MG-H1, CMA and pentosidine) as well as two mature and three immature enzymatic crosslinks.
View Article and Find Full Text PDFThe accumulation of advanced glycation end-products (AGEs) correlates with aging and accompanies the onset of age-related diseases, such as diabetes and arteriosclerosis. Therefore, a daily intake of natural compounds that inhibit the production of AGEs may be beneficial in preventing these diseases. In this study, we evaluated the inhibitory effects of 14 natural crude extracts, including those of Drosera species, which possess anti-inflammatory activity, on the formation of AGEs, such as N-(carboxymethyl)arginine (CMA) and N-(carboxymethyl)lysine (CML).
View Article and Find Full Text PDFOsteoporosis is an aging-associated disease that is attributed to excessive osteoblast apoptosis. It is known that the accumulation of advanced glycation end products (AGEs) in bone extracellular matrix deteriorates osteoblast functions. However, little is known about the interaction between intracellular AGE accumulation and the induction of osteoblast apoptosis.
View Article and Find Full Text PDFRoxb. is an annual aquatic grass of the citrus family. Although its hot water extract displays antioxidative activity , little is known about its biological effectiveness.
View Article and Find Full Text PDFJ Nutr Sci Vitaminol (Tokyo)
June 2020
Pentosidine is the most well-characterized advanced glycation end product (AGE). It has been measured by HPLC, although this approach cannot be adapted to analyze many clinical samples and is also time-consuming. Furthermore, the detection of pentosidine using a reported ELISA kit and HPLC system requires pretreatment by heating, which generates artificial pentosidine leading to overestimation.
View Article and Find Full Text PDFProlonged hyperglycemia generates advanced glycation end-products (AGEs), which are believed to be involved in the pathogenesis of diabetic complications. In the present study, we developed a polyclonal antibody against fructose-modified proteins (Fru-P antibody) and identified its epitope as glucoselysine (GL) by NMR and LC-electrospray ionization (ESI)- quadrupole TOF (QTOF) analyses and evaluated its potential role in diabetes sequelae. Although the molecular weight of GL was identical to that of fructoselysine (FL), GL was distinguishable from FL because GL was resistant to acid hydrolysis, which converted all of the FLs to furosine.
View Article and Find Full Text PDFAdvanced glycation end products (AGEs) accumulate in proteins during aging in humans. In particular, the AGE structure -(carboxymethyl)arginine (CMA) is produced by oxidation in glycated collagen, accounting for one of the major proteins detected in biological samples. In this study, we investigated the mechanism by which CMA is generated in collagen and detected CMA in collagen-rich tissues.
View Article and Find Full Text PDFApproximately 20% of diabetic patients develop diabetic cataracts. As lens proteins are known to be only slightly metabolized during the lifetime, cataracts are difficult to recover from once they have progressed. Therefore, the daily intake of natural compounds would be an important strategy for the prevention of diabetic cataracts.
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