Advanced glycation end products (AGEs) are formed by the Maillard reaction, a nonenzymatic process that occurs widely in cooking, food processing, and within the human body. Primarily, AGEs are formed by the glycation of reducing sugars with amino groups, and this process is heat-dependent. With changes in lifestyle, there has been an increase in the diversity of dietary habits, including those patterns associated with Western diets, which include the consumption of processed foods that are rich in AGEs. Excessive intake and exposure to AGEs are known to cause abnormalities in body function such as obesity, diabetes, and fatty liver, and the beneficial effects of AGEs in food processing in improving food flavor and quality. To obtain meaningful data regarding AGEs in a variety of food and human samples, it is necessary to more precisely characterize and analyze the AGEs extracted from samples to obtain accurate results. This review explores the recent analytical research and characterization of AGEs in foods, including casein, β-lactoglobulin, soy protein, and meat protein, and in human samples, such as glycated-albumin, hemoglobin, and plasma. Additionally, it explores the metabolic fate of AGEs in the body and the mechanisms of disease associated with metabolic abnormalities that may be caused by the consumption of foods containing AGEs. This review aims to provide an overview of the perspectives of relevant recent and future research on metabolic abnormalities caused by foods containing AGEs or by AGEs produced in the body.

Advanced 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. Serum samples from patients with diabetes, with or without macrovascular complications (Mac or non-Mac) or microvascular complications (Mic or non-Mic), were processed with the established methods. Free and total AGE levels in sera were measured using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). In patients with diabetes, both free and total AGE levels were elevated in those with complications compared to those without complications. In Mac and Mic groups, free and total AGE levels and z-scores (the sum of normalized AGE levels) also increased. AGE z-scores were markedly higher than those of single AGE levels in distinguishing each complication. Our study demonstrated that the free AGE z-score, measured using a new analytical method without hydrolysis, correlated with the presence of vascular complications and may serve as a marker of disease complications.

BACKGROUND: Glycated albumin (GA) is an indicator of glycemic variability over the past 2-4 weeks and has suitable characteristics for predicting the prognosis of ischemic stroke during the acute phase. This study evaluated the association between early neurological deterioration (END) and GA values in patients with acute ischemic stroke (AIS).
METHODS: We assessed consecutive patients with AIS between 2022 and 2023 at two large medical centers in Korea. END was defined as an increase of ≥ 2 in the total National Institutes of Health Stroke Scale (NIHSS) score or ≥ 1 in the motor NIHSS score within the first 72 h of admission. We evaluated various glycemic parameters including fasting glucose (mg/dL), hemoglobin A1c (%), and GA (%).
RESULTS: In total, 531 patients with AIS were evaluated (median age: 69 years, male sex: 66.3%). In the multivariable logistic regression analysis, GA value was positively associated with END (adjusted odds ratio [aOR] = 3.24, 95% confidence interval [CI]: 1.10-9.50). Initial NIHSS score (aOR = 1.04, 95% CI: 1.01-1.08) and thrombolytic therapy (aOR = 2.06, 95% CI: 1.14-3.73) were also associated with END. In a comparison of the predictive power of glycemic parameters for END, GA showed a higher area under the curve value on the receiver operating characteristic curve than fasting glucose and hemoglobin A1c.
CONCLUSIONS: High GA values were associated with END in patients with AIS. Furthermore, GA was a better predictor of END than fasting glucose or hemoglobin A1c.

Advanced glycated end products (AGEs) are cytotoxic compounds that are mainly increased in diabetes mellitus (DM), kidney failure, inflammation, and in response to the ingestion of AGE-rich diets. AGEs can also impair glycemic homeostasis by decreasing the expression of the Slc2a4 (solute carrier family 2 member 4) gene and its GLUT4 (solute carrier family 2, facilitated glucose transporter member 4) protein in muscle. However, the mechanisms underlying AGE\'s effect on adipocytes have not been demonstrated yet. This study investigated the effects of AGEs upon Slc2a4/GLUT4 expression in 3T3-L1 adipocytes, as well as the potential role of NFKB (nuclear factor NF-kappa-B) activity in the effects observed. Adipocytes were cultured in the presence of control albumin (CA) or advanced glycated albumin (GA) at concentrations of 0.4, 3.6, and 5.4 mg/mL for 24 h or 72 h. Slc2a4, Rela, and Nfkb1mRNAs were measured by RT-qPCR, GLUT4, IKKA/B, and p50/p65 NFKB subunits using Western blotting, and p50/p65 binding into the Slc2a4 promoter was analyzed by chromatin immunoprecipitation (ChIP) assay. GA at 0.4 mg/mL increased Slc2a4/GLUT4 expression after 24 h and 72 h (from 50% to 100%), but at 5.4 mg/mL, Slc2a4/GLUT4 expression decreased at 72 h (by 50%). Rela and Nfkb1 expression increased after 24 h at all concentrations, but this effect was not observed at 72 h. Furthermore, 5.4 mg/mL of GA increased the p50/p65 nuclear content and binding into Slc2a4 at 72 h. In summary, this study reveals AGE-induced and NFKB-mediated repression of Slc2a4/GLUT4 expression. This can compromise the adipocyte glucose utilization, contributing not only to the worsening of glycemic control in DM subjects but also the impairment of glycemic homeostasis in non-DM subjects under the high intake of AGE-rich foods.

The aim of this study was to evaluate the association between the Mediterranean diet (MD) and the accumulation of advanced glycation end products (AGEs) measured by skin autofluorescence. This cross-sectional study included 1016 healthy students from the University of Split, Croatia. Participants completed a self-administered questionnaire. Adherence to the MD was assessed using the Mediterranean Diet Serving Score (MDSS), and tissue AGEs accumulation was measured using the AGE Reader mu (DiagnOptics). Multivariate linear regression was used in the analysis. Students\' age and female gender were associated with higher levels of AGEs, which was likewise found for greater coffee intake, adequate olive oil consumption, smoking, and lower levels of physical activity. Higher consummation of vegetables and eating breakfast regularly were associated with lower AGEs levels. The overall MD adherence was not associated with AGEs, possibly due to very low overall compliance to the MD principles among students (8.3% in women and 3.8% in men). Health perception was positively associated with the MD and nonsmoking and negatively with the perceived stress level, while AGEs did not show significant association with self-rated students\' health. These results indicate that various lifestyle habits are associated with AGEs accumulation even in young and generally healthy people. Hence, health promotion and preventive measures are necessary from an early age.

The aim of the study was to evaluate the association of the quality of diet as calculated by the Nutrient Rich Food index (NRF9.3), and length of service (LS) (≤10 years vs. >10 years) with selected serum biochemical parameters, the proportions of different lipid profile fractions and advanced glycation endproduct (AGE) values of 108 firefighters from the State Fire Service in Wroclaw. The LS officers > 10 years had significantly higher total cholesterol (211.50 (184.00-254.00) vs. 184.00 (166.00-194.00)), LDL (123.75 (108.20-167.90) vs. 105.18 (90.24-119.00)) non-HDL (151.70 (132.00-196.70) vs. 122.00 (106.00-140.00)), triglycerides (118.50 (96.00-158.00) vs. 78.00 (67.00-103.00)) and lower HDL concentrations (51.30 (45.60-56.70) vs. 58.00 (51.70-66.10)) compared to firefighters in the LS ≤ 10 years group. Significant differences between the seniority groups were also noted for all lipid profile ratios. Regardless of the officers\' seniority, systolic blood pressure was observed at the highest normal level of 134.4 ± 14.4 in the LS ≤ 10 years group and 139.5 ± 14.3 in the LS > 10 years group. Advanced glycation endproduct values were significantly dependent on diet quality, as expressed by the NRF9.3 index and on the TG/HDL ratio, but not on seniority. Diet quality, as expressed by the NRF9.3 index, had a significant association with GLU and FI levels, and components of the lipid profile between seniority groups. As NRF9.3 increased, TG/HDL, LDL/HDL, TC/HDL, and non-HDL/HDL ratios decreased. AGEs were significantly affected by NRF9.3 and significantly associated with TG/HDL. Firefighters\' diets, as assessed by the NRF9.3 index, had a significant association with predictors of insulin resistance, diabetes, and cardiometabolic predictors between seniority groups. The nutritional education of firefighters (and other professional groups working irregularly), especially those with longer tenure (e.g., >10 years), is necessary to prevent the development of, e.g., CVD, MetS, and T2DM, which contribute towards a reduced ability to perform professional duties.

The current study intended to investigate the role of new natural compounds derived from the Sesuvium sesuvioides plant in mitigating symptoms of diabetes and insulin resistance in the diabetic mice model. Anti-advanced glycation activity, insulin, and adiponectin were quantified by enzyme-linked immunosorbent assay (ELISA). Glucose uptake was performed using enzymatic fluorescence assay, and glycogen synthesis was measured using PAS staining. Gene and protein expression was assessed using real time PCR (RT-PCR), and immunoblotting and fluorescent microscopy, respectively. The new flavonoid glycoside eupalitin 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside 1 isolated from S. sesuvioides exhibited anti-AGE activity by reducing human glycated albumin in liver cells. In a diabetic mouse model treated with compound 1, we observed improved glucose tolerance, increased adiponectin levels, and decreased insulin resistance. We also observed alleviated AGEs induced reduction in glucose uptake and restored glycogen synthesis in the compound 1-treated diabetic mice muscles. Exploring the molecular mechanism of action in skeletal muscle tissue of diabetic mice, we found that 1 reduced AGE-induced reactive oxygen species and the inflammatory gene in the muscle of diabetic mice. Additionally, 1 exhibited these effects by reducing the gene and protein expression of receptor for advanced glycation end products (RAGE) and inhibiting protein kinase C (PKC) delta activation. This further led us to demonstrate that compound 1 reduced serine phosphorylation of IRS-1, thereby restoring insulin sensitivity. We conclude that a new flavonoid glycoside from S. sesuvioides could be a therapeutic target for the treatment of symptoms of insulin resistance and diabetes.

Diabetes mellitus, characterized by dysregulated glucose metabolism, oxidative stress, and the formation of advanced glycation end products, poses a significant global health burden. In this study, we explored the potential of sorghum (Sorghum bicolor) seeds, known for their abundant phytochemical composition, as a natural remedy for diabetes and its associated damage. High-performance liquid chromatography/high-resolution mass spectrometry analysis revealed a remarkable phenolic richness in sorghum grains, including gallic acid, quercetin, and the predominant procyanidin B-1, with ecotype-specific variations in flavonoid distribution. Elemental analysis by ICP showed an abundance of macro-elements (Ca, K, Mg), trace elements (Fe, Mn, Si, Zn), and ultra-trace elements (B, Co, Cr, Cu, Mo, Se, V) essential for human health, supporting its therapeutic and nutritional potential. Additionally, the results demonstrated variable total phenolic contents (188-297 mg GAE/g dE) and total flavonoid contents (66-78 mg QE/g dE), with corresponding differences in antioxidant activities across the five ecotypes. Treatment with sorghum seed extract (SE1) significantly reduced oxidative stress markers, such as malondialdehyde (MDA)by 40% and hydrogen peroxide (H2O2) by 63%, in diabetic mice, compared to untreated diabetic controls. Moreover, sorghum extracts exhibited a remarkable increase in antioxidant enzyme activities, including a 50% increase in superoxide dismutase (SOD) activity and a 60% increase in glutathione peroxidase (GPx) activity, indicating their potential to bolster antioxidant defenses against diabetes-induced oxidative stress. These findings underscore the therapeutic potential of sorghum seeds in diabetes management and prevention, paving the way for the development of functional foods with enhanced health benefits.

Type 2 diabetes mellitus (T2DM) can lead to multiple complications. T2DM-related bone damage has been linked to abnormal bone turnover, but it cannot fully explain the mechanisms of T2DM bone disease. This study attempts to elucidate the underlying mechanisms of poor bone quality in T2DM. Hence, T2DM model was induced by a high-fat diet combined with a single streptozotocin injection in 7-week-old male SD rats. Osteoblasts derived from SD rats were cultured in high glucose to mimic hyperglycemia. Low bone turnover was observed in T2DM bone with elevated levels of advanced glycation end-products (AGEs) and receptor for AGEs (RAGE). Additionally, higher levels of oxidative stress and inflammatory factors were found in T2DM bone. AGEs content in bone was pairwise correlated with RAGE, hydrogen peroxide, and inflammatory factors. Serum levels of RAGE, oxidative stress, and inflammatory factors were higher in T2DM, while AGEs content tended to be lower. Besides, 35 differentially expressed metabolites were screened in T2DM serum. Osteoblasts exposed to high glucose displayed analogous abnormal changes in these biomarkers. Thus, low bone turnover in T2DM might be partially due to excess oxidative stress and inflammation induced by AGE-RAGE signaling. Furthermore, these biomarker levels in serum were mostly consistent with bone, demonstrating their possibility for predicting bone quality in T2DM.

OBJECTIVE: To clarify the role of advanced glycation end products (AGEs) and inflammation in the development of vascular calcification and cardiovascular complications at different stages of chronic kidney disease (CKD) G1-G5D.
METHODS: We examined 105 patients aged 19 to 75 years with stage C1-C5D CKD, 77 (74%) of whom were patients with diabetic nephropathy. The concentration of AGEs, interleukin (IL)-1, IL-6 and tumor necrosis factor α (TNF-α), troponin I, parathyroid hormone was determined by enzyme-linked immunosorbent assay (ELISA) using kits from BluGene biotech (Shanghai, China), Cloud-Clone Corp. (USA), ELISA Kit (Biomedica, Austria).
RESULTS: A high content of AGEs, IL-1, IL-6, TNF-α was established, which directly correlated with the increase in renal failure and changes in the morpho-functional parameters of the left ventricle and aorta.
CONCLUSIONS: An increase in serum concentrations of AGEs and inflammatory mediators, correlating with a decrease in renal function and changes in the morpho- functional parameters of the left ventricle and aorta, indicate their significant role in the processes of damage to the cardiovascular system in CKD.
Цель. Уточнить роль конечных продуктов гликирования (advanced glycation end products – AGEs) и воспаления в развитии сосудистой кальцификации и сердечно-сосудистых осложнений на разных стадиях хронической болезни почек (ХБП) – С1–С5Д. Материалы и методы. Обследованы 105 пациентов в возрасте от 19 до 75 лет с ХБП С1–С5Д-стадии, 77 (74%) из которых были больные с диабетической нефропатией. Концентрацию AGEs, интерлейкина (ИЛ)-1, ИЛ-6 и фактора некроза опухоли α (ФНО-α), тропонина I, паратиреоидного гормона определяли методом иммуноферментного анализа с применением наборов фирм BluGene biotech (Shanghai, Китай), Cloud-Clone Corp. (США), ELISA Kit (Biomedica, Австрия). Результаты. Установлено высокое содержание показателей AGEs, ИЛ-1, ИЛ-6, ФНО-α, прямо коррелировавших с нарастанием почечной недостаточности и изменениями морфофункциональных параметров левого желудочка и аорты. Заключение. Повышение сывороточных концентраций AGEs и медиаторов воспаления, коррелирующее со снижением функции почек и изменениями морфофункциональных параметров левого желудочка и аорты, свидетельствуют об их значительной роли в процессах поражения кардиоваскулярной системы при ХБП.