Advanced glycation endproducts in food and their effects on health

Synergistic effects of polymethoxyflavonoids from citrus peel extracts on harmful compound formation and flavor quality in grilled beef patties

Three polymethoxyflavonoids (PMFs) from citrus peel: tangeretin (TG), isosinensetin (ISN), and 3',4',5,7-tetramethoxyflavone (TMHF) and their combination significantly inhibited heterocyclic amines (HAs) and advanced glycation-end products (AGEs) formation. In particular, ISN with five methoxyl structure and B-ring distribution was significantly effective reduce HAs to 50.1 %-77.9 %. The PMF mixture was effective reduce both HAs and AGEs at rates of 52.2 %-77.3 % and 16.4 %-66.8 %, respectively. For ISN, the radical scavenging activity and inhibitory effects of HAs and AGEs were highly correlated. However, the inhibitory action of mixed PMFs against harmful substances was related to free radical scavenging activity and their impact on water distribution. Furthermore, GC-IMS analysis revealed the PMF mixture did not significantly change the key aldehyde and ketone compounds in grilled meat. This study provides insights into the effect of PMF mixtures, which appear to synergistically regulate the formation of aromatic and harmful compounds in grilled meat products.

High-moisture extruded pea balls exhibit lower (glyc)oxidative stability than pork balls following barbecuing and simulated gastrointestinal digestion

The (glyc)oxidation of model meat and plant-based balls during barbeque heating and subsequent simulated gastrointestinal digestion was investigated. For this purpose, balls were formulated with pork, or high-moisture extruded (HME) pea isolate, to which three types of carbohydrates (glucose, sucrose or starch) and/or a herbal mixture were added. Heated protein products were evaluated before and after digestion for the various (glyc)oxidation products, including α-oxoaldehydes (glyoxal, methylglyoxal, 3-deoxyglucosone), lipid oxidation products (4-hydroxy-2-nonenal, hexanal, propanal, thiobarbituric acid reactive substances), protein oxidation products (protein carbonyl compound), and advanced glycation endproducts (Nε-(carboxymethyl)lysine, Nε-(carboxyethyl)-lysine, pentosidine, Nd-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine, argpyrimidine). Overall, digested pea balls contained similar or significantly higher levels of various (glyc)oxidation products compared to their pork counterparts. These differences could be related to several factors, including the initial (glyc)oxidative status of the raw materials, the addition of carbohydrates, and the progression of (glyc)oxidative reactions during heating and gastrointestinal digestion. Herbs only marginally affected these reactions.

Preparation, identification and application of lipid-Maillard reaction products during the drying process of squid fillets

Squid fillets are susceptible to lipid oxidation and Maillard reaction during the drying process. In this study, a novel additive agent lipid-Maillard reaction products (L-MRPs) was optimized by response surface methodology, then the main antioxidant components of L-MRPs were identified. Finally, L-MRPs was applied to the drying process of squid fillets (LMSF) by comparing with the control group. The results showed that the optimal reaction conditions were pH 10.90, lipid content 1.70 %, reaction temperature 104 °C, reaction time 105 min. The DPPH radical scavenging activity of final L-MRPs was 89.78 %. The main antioxidant components of L-MRPs were Fru-Arg (19.31 μg/g), pyrroles (762.04 μg/g) and other HCCs (293.97 μg/kg). Besides, compared to the control group, LMSF group showed lower thiobarbituric acid reactive substances value (4.58 mg/kg) and formaldehyde content (17.00 mg/kg), but more flavor compounds (455.78 μg/kg) and higher sensory scores. Finally, the potential antioxidant and flavor-enhancing mechanism of L-MRPs was proposed.

Interlinking diabetes and Alzheimer's disease: A pathway through medicinal plant-based treatments

ETHNOPHARMACOLOGICAL RELEVANCE

Indian traditional medicine has long utilized medicinal plants for the management of chronic diseases such as Diabetes mellitus (DM) and related neurological complications, Alzheimer's disease (AD). The growing global burden of DM and its associated complications continues to rise; hence, it seems essential to explore effective, targeted therapies to mitigate their progression. Plant-based therapeutics have garnered significant attention for their safety, efficacy and ability to modulate multiple biological pathways. Indigenous medicinal plants, such as Sesbania grandiflora (L.) Poir., Moringa oleifera Lam., Centella asiatica (L.) Urb., Psidium guajava (L.), Aegle marmelos (L.) Corrêa, and Catharanthus roseus (L.) G. Don has been historically employed in ethnomedicine such as classical Ayurvedic texts, scientific literature and has a comprehensive and synergistic approach to address symptoms associated with DM and cognitive decline.

AIM OF THE STUDY

This review explores the interwined pathophysiological pathways between DM and AD, highlighting the potential of medicinal plants through (pre-clinical and clinical evidence), bridging the therapeutic gap. Additionally, we also discussed the currently used conventional antidiabetic drug that has been employed for managing AD.

RESULTS

In this study, six ayurvedic plants with dual activity against DM and AD are thoroughly reviewed with historical context, preclinical and clinical context. The plant's secondary metabolites have demonstrated significant antidiabetic and neuroprotective activities by regulating glucose metabolism, reducing oxidative stress, preventing amyloid-beta accumulation, etc. CONCLUSION: DM and AD share pathophysiology and multifaceted causes, requiring multi-targeted herbal remedies. The selected six Ayurveda medicinal plants showcase the dual benefits for both diseases. The obstacles, such as stability, pharmacokinetics, and safety, remain substantial barriers; addressing these challenges could constrain the clinical translation. This review demands further research to address the challenges to facilitate the effective integration of traditional medicinal knowledge with contemporary practice.

Cooking methods affect advanced glycation end products and lipid profiles: A randomized cross-over study in healthy subjects

Thermal treatments used in ultra-processed foods (UPFs) lead to advanced glycation end products (AGEs). UPFs and serum AGEs are associated with cardiometabolic disease. We explore differential cooking methods as a mechanistic link between UPFs and detrimental health outcomes through a randomized cross-over cooking method trial in healthy subjects using identical ingredients and a deep profiling analysis. We show that low-AGE-generating cooking methods such as boiling and steaming decrease serum AGEs, improve lipid profiles, and increase serum protein 4E-BP1. In contrast, high-AGE-generating cooking methods such as grilling and baking increase fecal butyrate. In sum, this suggests that low-AGE-generating cooking methods should be considered in cardiovascular risk prevention. Since current dietary guidelines focus on ingredients, but not cooking methods, our results suggest that culinary techniques should be considered as an important factor in cardiometabolic preventive strategies and future dietary trial design. This study was registered at ClinicalTrials.gov (NCT06547190).

Variation in albumin glycation rates in birds suggests resistance to relative hyperglycaemia rather than conformity to the pace of life syndrome hypothesis

The pace of life syndrome (POLS) hypothesis suggests that organisms' life history and physiological and behavioural traits should co-evolve. In this framework, how glycaemia (i.e. blood glucose levels) and its reaction with proteins and other compounds (i.e. glycation) covary with life history traits remain relatively under-investigated, despite the well-documented consequences of glucose and glycation on ageing, and therefore potentially on life history evolution. Birds are particularly relevant in this context given that they have the highest blood glucose levels within vertebrates and still higher mass-adjusted longevity compared to organisms with similar physiology as mammals. We thus performed a comparative analysis on glucose and albumin glycation rates of 88 bird species from 22 orders in relation to life history traits (body mass, clutch mass, maximum lifespan, and developmental time) and diet. Glucose levels correlated positively with albumin glycation rates in a non-linear fashion, suggesting resistance to glycation in species with higher glucose levels. Plasma glucose levels decreased with increasing body mass, but, contrary to what is predicted in the POLS hypothesis, glucose levels increased with maximum lifespan before reaching a plateau. Finally, terrestrial carnivores showed higher albumin glycation compared to omnivores despite not showing higher glucose, which we discuss may be related to additional factors as differential antioxidant levels or dietary composition in terms of fibres or polyunsaturated fatty acids. These results increase our knowledge about the diversity of glycaemia and glycation patterns across birds, pointing towards the existence of glycation resistance mechanisms within comparatively high glycaemic birds.

Association of Dietary Advanced Glycation End Products with Overall and Site-Specific Cancer Risk and Mortality: A Systematic Review and Meta-Analysis

Background/Objectives: Dietary advanced glycation end products (dAGEs) have a pro-inflammatory effect and increase oxidative stress, potentially leading to cancer. The aim of this study was to estimate the association between dAGEs consumption and risk and mortality from overall cancer and according to its site. Methods: A systematic search was conducted in Medline, Scopus, Web of Science, and the Cochrane Library from inception to April 2025. The search strategy was conducted according to the PECO structure adapted to this study, as well as the inclusion criteria, in which the population (P) was the adult population, the exposure (E) was the highest level of dAGEs intake, the comparator (C) was the lowest level of dAGEs intake, and the outcomes (O) were the overall cancer risk, cancer risk by site, and cancer mortality. Results across studies were summarised using random effects and fixed effects. Results: Fourteen studies were included in the systematic review. In the random-effects meta-analysis, high dAGEs intake was associated with Hazard Ratio (HR) = 0.99 [95% Confidence Interval (95% CI): 0.98, 1.00] for overall cancer risk. However, although there was no association with breast cancer (BC), there was an association with invasive BC, with HR = 1.14 (95% CI: 1.05, 1.23). In contrast, in other tumours, there were opposite results depending on the site of the cancer. Conclusions: The reduction in cancer risk is not clinically significant. However, high consumption of dAGEs may increase the risk of BC, particularly the invasive BC, which is a challenge for cancer prevention and subsequent mortality. Due to the limited evidence, further studies are needed to confirm the potential impact of dAGEs, as well as other dietary factors that may play a larger role in cancer development.

Monitoring furanic and dicarbonyl compounds in pea-based and wheat-based sponge cakes during in vitro digestion

The increasing tendency to use animal-free and gluten-free proteins leads to replacing traditional with legume-based ingredients. Of these, refined pea (Pisum sativum L.) is gaining momentum due to its availability, nutritional value and low allergenicity. However, little is known of the propensity of pea ingredients to generate process-induced compounds in high-temperature processed foods, and the reactivity of contaminant during digestion. This study explored the levels and behavior of selected newly formed compounds (NFCs) (furfural, 5-(hydroxymethyl)furfural (HMF), 3-deoxyglucosone (3-DG), 1-deoxyglucosone (1-DG), glyoxal (GO), methylglyoxal (MGO), dimethylglyoxal (DMGO), glucosone (GCO)) in a pea-based sponge cake baked at 200 °C and subjected to in vitro digestion, by comparison with a reference wheat-based cake. The pea formulation generated the highest levels of furanic and dicarbonyl compounds, with 3-DG and HMF being the most abundant (162.44 ± 2.79 and 270.61 ± 14.91 μg/g dry cake, respectively), compared to the wheat-based formulation (131.43 ± 4.34 and 166.83 ± 0.88 μg/g dry cake, respectively). The differences in NFC levels between pea- and wheat-based cakes were maintained during in vitro digestion. Generally, furanic compounds decreased, glyoxales increased and deoxyglucosones were more stable during digestion. Surprisingly, even after any decrease, NFC levels remained high at the end of digestion in both pea- and wheat-based products (up to 215.18 ± 0.42, 188.96 ± 3.02, and 15.76 ± 0.26 μg/g dry cake for HMF, 3-DG, and MGO, respectively). These amounts resulted from the balance between formation and consumption reactions, influenced by gastric and intestinal environments and cake composition. This study has therefore highlighted key safety aspects by considering the behavior during digestion of process-induced compounds in complex, legume-based food matrices.

Cracking the code of acrylamide and Nε-(carboxymethyl)lysine: Fish oil use and predictive strategies in potato chips during thermal processing

Global high consumption of fried potatoes is driven by appealing taste and edible convenience. However, the occurrence of Maillard reaction hazardous products (MRHPs) and joint control recipes have scarcely been concerned. We aim to reveal and predict how fish oil treatment for potato slices reduces simultaneous formation of typical MRHPs in air-based thermal processed potato chips. Fish oil, for the first time, was considered as a nutritional agent for the mitigation of acrylamide (AA) and Nε-(carboxymethyl)lysine (CML). The addition of fish oil at 30 μL/g significantly reduces the formation of AA, free CML, and bound CML by 39.2 %, 27.3 %, and 14.9 %, respectively, during thermal processing at 160 °C for 20-30 min in air-based thermal processed potato chips. The random forest model demonstrated strong adaptability with R2 > 0.8, indicating high accuracy and reliability for the prediction. These findings significantly contribute to the understanding of MRHP control and food safety in fried food industry.

Effect of myoglobin on the flavor, color and texture of high-moisture soy protein concentrate -wheat gluten extrudates

The rising demand for plant-based meat analogues presents challenges in replicating the sensory qualities of animal meat. This study investigates the impact of Pichia-derived porcine myoglobin (PMb) and bovine hemoglobin (BHb) on the flavor profile, sensory attributes, macrostructure, color, and texture of high-moisture extruded soy protein concentrate-wheat gluten. The addition of PMb and BHb significantly altered the flavor profile by decreasing aldehyde content (hexanal and nonanal), while the contents of ketones (2,3-octanedione and 3,5-octadien-2-one), pyrazines (2-ethyl-6-methylpyrazine), and furans (2-pentylfuran) were increased. The structure of 0.5 % PMb and BHb extrudates exhibited a laminar arrangement, whereas 1 % PMb resulted in a uniform, gelatinous texture. Color analysis showed 0.5 % PMb darkened and reddened the extrudates, with the a⁎ value increasing from 5.51 ± 0.50 to 6.44 ± 0.57, and the a⁎ value reached 8.33 ± 0.37 when 1 % PMb was added. These findings offer valuable insights into the development of plant-based meat analogues.

Advanced Glycation End Products in Disease Development and Potential Interventions

Advanced glycation end products (AGEs) are a group of compounds formed through non-enzymatic reactions between reducing sugars and proteins, lipids, or nucleic acids. AGEs can be generated in the body or introduced through dietary sources and smoking. Recent clinical and animal studies have highlighted the significant role of AGEs in various health conditions. These compounds accumulate in nearly all mammalian tissues and are associated with a range of diseases, including diabetes and its complications, cardiovascular disease, and neurodegeneration. This review summarizes the major diseases linked to AGE accumulation, presenting both clinical and experimental evidence. The pathologies induced by AGEs share common mechanisms across different organs, primarily involving oxidative stress, chronic inflammation, and direct protein cross-linking. Interventions targeting AGE-related diseases focus on inhibiting AGE formation using synthetic or natural antioxidants, as well as reducing dietary AGE intake through lifestyle modifications. AGEs are recognized as significant risk factors that impact health and accelerate aging, particularly in individuals with hyperglycemia. Monitoring AGE level and implementing nutritional interventions can help maintain overall health and reduce the risk of AGE-related complications.

Method validation for analysis of advanced glycation end products in mouse muscle tissue using liquid chromatography-tandem mass spectrometry

Advanced glycation end products (AGEs) in food and biological samples have been analyzed using several chromatographic and immunological methods, but no studies have quantitatively analyzed the major AGEs, Nε-carboxy-methyl-lysine (CML) and Nε-carboxy-ethyl-lysine (CEL), in muscle tissue. In this study, a quantitative profiling method using ultra-performance liquid chromatography-tandem mass spectrometry in mouse muscle tissue was developed and validated. For extraction, acid hydrolysis and solid-phase extraction were performed. The CML and CEL were well separated and analyzed within 5 min in multiple reaction monitoring mode. The method was validated against ICH guidelines to evaluate the linearity, limits of detection and quantification, matrix effects, recovery, accuracy, and precision, and the validated approach was applied to muscle tissue from aged mice to establish a baseline for the typical range of CML and CEL. This quantitative profiling method has the potential to be applied in the study of diseases influenced by AGEs.

Comparison of Metabolic and Hormonal Profiles between Low-Advanced Glycation End Products (AGEs) and Standard AGEs-Containing Weight-Loss Diets in Overweight Phenotype-A PCOS Patients: A Randomized Clinical Trial

This study aims to investigate the effects of a low-advanced glycation end products(AGEs) diet versus a standard AGE-containing weight-loss diet on metabolic and hormonal profiles of overweight phenotype-A polycystic ovary syndrome(PCOS) patients.A randomized controlled interventional study.A total of 44 Rotterdam phenotype-A PCOS patients aged 19-35 were enrolled between January 2022 and May 2023. They were randomly assigned to 12-weeks of an energy-restricted Standard-AGEs diet(S-AGEs) or an energy-restricted Low-AGEs diet(L-AGEs). At baseline and after 12-weeks of intervention, weight loss, oligo-amenorrhea, hormonal profiles, plasma lipid profiles, and inflammation markers were evaluated. During the intervention, 8 participants from the L-AGEs group and 6 from the S-AGEs group dropped out. Completers had similar baseline characteristics to dropouts. In the per-protocol analysis, similar weight loss was observed in the L-AGEs(n = 14) and S-AGEs(n = 16) groups compared to baseline weight [-8.4 [-10.3 to -5.8] vs. -5.2 [-8.8 to -4.6] kg, respectively, p = 0.183]. However, in the L-AGEs group, fasting glucose levels decreased significantly more compared to the S-AGEs group (-8.5 [-11.5 to -3.5] vs. -0.5 [-3.7 to 0.7] mmol/L, respectively, p = 0.027). Following the diet intervention in the L-AGEs group, the waist-to-hip circumference ratio, LDL-cholesterol, TNF-α, total testosterone (TT), free-androgen index (FAI), and anti-Müllerian hormone (AMH) levels significantly decreased compared to baseline levels, while sex hormone-binding globulin (SHBG) levels increased. In contrast, there was no statistically significant change in these parameters in the S-AGEs group.In addition to weight-loss, reducing dietary AGEs intake resulted in significantly greater improvements in metabolic and hormonal profiles among phenotype-A PCOS patients. Clinicaltrials.gov registration no. NCT05830487.

The role of AGEs in muscle ageing and sarcopenia

Sarcopenia is an ageing-related disease featured by the loss of skeletal muscle quality and function. Advanced glycation end-products (AGEs) are a complex set of modified proteins or lipids by non-enzymatic glycosylation and oxidation. The formation of AGEs is irreversible, and they accumulate in tissues with increasing age. Currently, AGEs, as a biomarker of ageing, are viewed as a risk factor for sarcopenia. AGE accumulation could cause harmful effects in the human body such as elevated inflammation levels, enhanced oxidative stress, and targeted glycosylation of proteins inside and outside the cells. Several studies have illustrated the pathogenic role of AGEs in sarcopenia, which includes promoting skeletal muscle atrophy, impairing muscle regeneration, disrupting the normal structure of skeletal muscle extracellular matrix, and contributing to neuromuscular junction lesion and vascular disorders. This article reviews studies focused on the pathogenic role of AGEs in sarcopenia and the potential mechanisms of the detrimental effects, aiming to provide new insights into the pathogenesis of sarcopenia and develop novel methods for the prevention and therapy of sarcopenia.

Joint control of multiple food processing contaminants in Maillard reaction: A comprehensive review of health risks and prevention

There is an urgent need to address food safety concerns associated with multiple Maillard reaction‒derived chemical contaminants, such as acrylamide, heterocyclic aromatic amines, advanced glycation end products, and 5-hydroxymethylfurfural, which are present in processed foods. Current studies have focused on single contaminant generated by the Maillard reaction; however, there is a dearth of information regarding the interactions of multiple contaminants and their joint control methods. This review article comprehensively summarizes the state-of-the-art progress in the simultaneous analysis, coformation, joint hazardous control, and risk assessment of multiple food processing contaminants generated by the Maillard reaction. The Maillard reaction is associated with caramelization, lipid oxidation, protein oxidation, and ascorbic acid browning reactions. Mass spectrometry‒based chromatography is currently the preferred method for the simultaneous quantification of multiple contaminants, with metabolomics and indirect detection methodologies providing new insights. Mitigation strategies for multiple contaminants include optimizing pretreatment, introducing exogenous additives, regulating processing parameters, and utilizing emerging technologies. Limited animal studies on the metabolism of various contaminants have yielded diverse results, guided by biomarkers for deep understanding. Integrated risk assessment should be conducted to quantify multihazard health impacts. In future research, a unique framework should be developed for assessing multiple contaminants, characterizing their metabolic profiles, and optimizing control measures for Maillard reaction‒derived contaminants.

Formation of acrylamide in commercially available plant-based meat alternatives during domestic cooking

The formation and occurrence of acrylamide in carbohydrate-rich foods has been extensively studied over the course of the past few decades. However, the emergence of plant-based meat alternatives presents a new challenge in this field. The aim of this study was to evaluate the levels of acrylamide in commercially available plant-based meat alternatives before and after heat treatment. Trace levels of acrylamide were detected in all samples before heat-treatment, while the concentrations increased in 11 samples out of 16 after heat-treatment. The highest concentration of acrylamide increased from 65.7 ± 6.6 µg kg-1 before to 119 ± 12 µg kg-1 after heat-treatment. Principal component analysis (PCA) indicated that besides macronutrient composition, the use of additives and processing techniques have a strong influence on acrylamide formation in plant-based meat alternatives. The latter was supported by the analysis of self-made meat alternative models that were prepared using only the base ingredients.

Emerging technologies in reducing dietary advanced glycation end products in ultra-processed foods: Formation, health risks, and innovative mitigation strategies

The widespread consumption of ultra-processed foods (UPFs) results from industrialization and globalization, with their elevated content of sugar, fat, salt, and additives, alongside the formation of dietary advanced glycation end products (AGEs), generating considerable health risks. These risks include an increased incidence of diabetes, cardiovascular diseases, and neurodegenerative disorders. This review explores the mechanisms of AGE formation in UPFs and evaluates emerging technologies and additives aimed at mitigating these risks. Both thermal methods (air frying, low-temperature vacuum heating, microwave heating, and infrared heating) and non-thermal techniques (high-pressure processing, pulsed electric fields, ultrasound, and cold plasma) are discussed for their potential in AGE reduction. Additionally, the review evaluates the efficacy of exogenous additives, including amino acids, polysaccharides, phenolic compounds, and nanomaterials, in inhibiting AGE formation, though results may vary depending on the specific additive and food matrix. The findings demonstrate the promise of these technologies and additives for reducing AGEs, potentially contributing to healthier food processing practices and the promotion of improved public health outcomes.

Health Benefits of Olive Leaf: The Focus on Efficacy of Antiglycation Mechanisms

Olive leaves have been a therapeutic herbal agent for diseases for centuries. Olive leaves contain many health-beneficial nutrients and bioactive components. There is much evidence for the positive effects of the phenolic compounds they contain on health. The main active phenolic component in olive leaves is oleuropein, which can constitute 6%-9% of the leaf's dry matter and has been intensively studied for its promising results/effects on human health. In addition, olive leaf provides health benefits through bioactive components, such as secoiridoids, flavonoids, triterpenes, and lignans. The anti-inflammatory, antioxidant, anticancer, antidiabetic, and antihypertensive properties of bioactive components, especially oleuropein, are well known. In addition, various health benefits, such as neuroprotective effects and microbiota modulation, are also mentioned. In recent years, in vitro studies have shown that olive leaves and bioactive components from olive leaves may have antiglycation effects. Currently, it is thought that the components found in olive leaves have a direct or indirect antiglycation effect. It is thought that, their direct effects include reducing the interaction between sugars and amino acids, nucleic acids, and lipids and sequestering reactive dicarbonyl species, and their indirect effects include preventing the formation of advanced glycation end-products (AGEs) by reducing inflammation and oxidative stress. However, in vivo and clinical studies are needed to prove these mechanisms and understand how their metabolism works in the human body. This review examines the beneficial health effects of olive leaves and their potential antiglycation role.

Accumulation of Nε-carboxymethyllysine and Nε-carboxyethyllysine in precooked pork during cold storage and subsequent reheating

This research aimed to investigate the levels of Nε-carboxymethyllysine (CML) and Nε-carboxyethyllysine (CEL) in precooked pork (100 °C, 10 min) as affected by storage (0 °C, 0-11 d) and subsequent reheating (100 °C, 5 min). A longer storage duration led to more CML (average increased: 69-128 %) and CEL (average increased: 11-44 %) in precooked pork, while the reheating resulted in average increases of 86 % CML and 32 % CEL compared to their initial levels in precooked pork. However, the storage duration did not significantly (p > 0.05) affect CML/CEL formation in precooked pork during the subsequent reheating. The levels of CML/CEL and glyoxal/methylglyoxal had no obvious relationship, but CML formation was linked to lipid oxidation in precooked or reheated pork. The accumulation of CML and CEL in precooked meat produced during the initial precooking, storage, and reheating implies the necessity to control their generation in these products.

Maternal AGE Precursors During Lactation Alters Offspring Glycemic Homeostasis Early in Life

BACKGROUND

Advanced glycation end-products (AGEs) are linked to the development of oxidative stress, insulin resistance, and impaired insulin secretion. Adverse early life conditions, such as exposure to AGEs and their precursors, may lead offspring to the development of metabolic dysfunction in adulthood. Nonetheless, the early impact in offspring metabolism by maternal intake of AGEs precursors during lactation is not known.

OBJECTIVE

Investigate early life metabolism of the offspring whose breastfeeding dams were orally exposed to AGEs precursor.

METHODS

Breastfeeding Wistar rats were daily treated with the glycation precursor methylglyoxal (MG-60 mg/kg of bodyweight) by gavage or saline 0.9% control (CO) until weaning. In vivo glycemic homeostasis in male offspring was assessed, followed by euthanasia for tissue sample collection for ex vivo assessments.

RESULTS

At weaning, MG offspring presented decreased bodyweight (p < 0.05), perigonadal (p < 0.01) and retroperitoneal (p < 0.01) fat. MG offspring presented decreased glucose tolerance (p < 0.05), lower basal insulinemia (p < 0.001), reduced high-glucose static insulin secretion (p < 0.05), and reduced pancreatic islet area (p < 0.05). Accordingly, MG offspring pancreas showed lower GSH and SOD activity (p < 0.05; p < 0.001, respectively) and increased MPO (p < 0.05) activity.

CONCLUSIONS

The consumption of AGE precursors by breastfeeding dams impaired offspring pancreatic function and glycemic homeostasis early in life.

Long-term effects of Nε-carboxymethyllysine intake on intestinal barrier permeability: Associations with gut microbiota and bile acids

Advanced glycation end products (AGEs) in processed foods are closely linked to intestinal injury. However, the long-term effects of exposure to free Nɛ-carboxymethyl lysine (CML), a prevalent AGE molecule, on intestinal barrier integrity have been rarely evaluated. This study investigated the temporal effects of CML exposure on intestinal barrier permeability in C57BL/6N mice at diet-related doses over 12, 14, and 16 weeks. No significant changes were observed at 12 weeks, but CML exposure significantly increased intestinal permeability at 14 and 16 weeks, accompanied by elevated serum LPS levels, colonic histological damage, and reduced tight junction protein expression at 16 weeks. CML exposure also altered gut microbiota composition and intestinal bile acid (BA) profiles, specifically reducing TDCA, GDCA, and GCDCA levels. Given the important role of colonic BA receptor signaling in maintaining the intestinal barrier integrity, the impact of CML on BA receptor signaling was assessed. CML exposure significantly downregulated BA receptor TGR5-YAP signaling in mice, while no significant effects were observed in vitro, suggesting that the changes observed in TGR5-YAP signaling in vivo may not result from the direct effects of CML. Spearman's correlation analysis revealed strong associations between altered gut microbiota, BA levels, TGR5-YAP signaling, and intestinal barrier injury. This study highlighted the chronic health risks of long-term CML intake and provided new insights into the links between CML-induced intestinal toxicity, gut microbiota, BA profiles, and BA receptor signaling.

Black mulberry (Morus nigra L.) prevents deleterious effects of excess glucose in obese C. elegans decreasing lipofuscin accumulation and ROS production

Black mulberries have been traditionally used as antidiabetic agents and are a source of nutrients and phenolic compounds, particularly anthocyanins. The objective of this work is to determine if Morus nigra berries could prevent metabolic and obesity-related disorders using in vitro systems and in vivo alternative models such as C. elegans. An aqueous solvent-free extract from Morus nigra fruits rich in phenolic compounds like chlorogenic acid, hyperoside, rutin and cyanidin 3-glucoside was evaluated in the C. elegans obese model subjected to high glucose concentrations evaluating different parameters such as lipid droplets, lipofuscin accumulation and ROS production. The capacity of the extract to inhibit advance glycation end products and free radicals as well as pancreatic lipase and α-amylase was also evaluated in vitro. The black mulberry extract showed a significant capacity to inhibit the accumulation of lipid droplets, reducing by 50.40 % the fat deposits. The extract was able to reverse the deleterious effects of excess glucose in C. elegans enhancing stress resistance, preventing the accumulation of lipofuscin, and decreasing the ROS production. The anti-glycation and antioxidant effects in vitro were higher than the reference substances aminoguanidine and quercetin respectively. Morus nigra was also able to inhibit the pancreatic enzymes α-amylase and lipase and could be considered an interesting traditional food ingredient in the prevention of certain metabolic diseases.

Multi-response kinetic study of Maillard reaction hazards in the glucose-lysine model system

BACKGROUND

Nε-carboxymethyllysine (CML), Nε-carboxyethyllysine (CEL) and α-aminoadipic acid (AAA) are important foodborne hazards and their intake can cause a variety of diseases in humans. It is extremely important to investigate the formation mechanism of CML, CEL and AAA, as well as their association with each other when aiming to control their production.

RESULTS

A multi-response kinetic model was developed within the glucose-lysine Maillard reaction model system. The concentrations of glucose, lysine, glyoxal (GO), methylglyoxal (MGO), CML, CEL and AAA were quantified at different temperature (100-160 °C) and at different intervals (0-60 min). The experimental data were fitted to the proposed model to calculate kinetic parameters for the corresponding steps. The results indicated that the production of CML was primarily relied on the direct oxidative cleavage of the Amadori product, rather than the reaction between GO and Lys, whereas CEL and AAA were generated through the reaction of MGO with Lys. Significantly, the reaction between α-dicarbonyl compounds and Lys preferentially generated CML and CEL, resulting in the lower concentrations of AAA compared to CML and CEL.

CONCLUSION

The multi-response kinetic model developed in the present study can be applied well to the Maillard reaction. The relationship between the formation mechanisms of CML, CEL and AAA is also explained. © 2024 Society of Chemical Industry.

Assessing metal-induced glycation in French fries

Non-enzymatic glycation is the chemical reaction between the amine group of an amino acid and the carbonyl group of a reducing sugar. The final products of this reaction, advanced glycation end-products (AGEs), are known to play a key role in aging and many chronic diseases. The kinetics of the AGE formation reaction depends on several factors, including pH, temperature, and the presence of prooxidant metals, such as iron and copper. In this study, the effect of iron and copper on the rate and outcome of non-enzymatic glycation was examined in the test tube and a food model, using chromatography and spectrometry methods. Binding efficiencies of several chelating agents to selected metals were also assessed. Phytic acid was the most efficient of the tested chelating agents. The effect of phytic acid on AGE formation in French fries was evaluated. While phytic acid treatment increased the amounts of UV-absorbing compounds in fries, a food ingredient rich in phytic acid showed the opposite effect. This study suggests that prooxidant metals can affect the rate, outcome, and yield of the non-enzymatic glycation reaction and that they do so differently when free or chelated. Moreover, despite being an excellent iron chelator, phytic acid can promote AGE formation in fried food potentially via mechanisms other than metal-induced glycation.

The Anti-AGEing and RAGEing Potential of Isothiocyanates

Isothiocyanates (ITCs), found in edible plants such as cruciferous vegetables, are a group of reactive organo-sulfur phytochemicals produced by the hydrolysis of precursors known as glucosinolates. ITCs have been studied extensively both in vivo and in vitro to define their therapeutic potential for the treatment of chronic health conditions. Therapeutically, they have shown an intrinsic ability to inhibit oxidative and inflammatory phenotypes to support enhanced health. This review summarizes the current evidence supporting the observation that the antioxidant and anti-inflammatory activities of ITCs temper the pathogenic effects of a group of reactive metabolites called advanced glycation end products (AGEs). AGE exposure has significantly increased across the lifespan due to health risk factors that include dietary intake, a sedentary lifestyle, and comorbid conditions. By contributing to a chronic cycle of inflammatory stress through the aberrant activation of the transmembrane receptor for AGE (RAGE), increased AGE bioavailability is associated with chronic disease onset, progression, and severity. This review debates the potential molecular mechanisms by which ITCs may inhibit AGE bioavailability to reduce RAGE-mediated pro-oxidant and pro-inflammatory phenotypes. Bringing to light the molecular impact that ITCs may have on AGE biogenesis may stimulate novel intervention strategies for reversing or preventing the impact of lifestyle factors on chronic disease risk.

1,2,4-Triazine derivatives as agents for the prevention of AGE-RAGE-mediated inflammatory cascade in THP-1 monocytes: An approach to prevent inflammation-induced late diabetic complications

INTRODUCTION

Monocytes mainly contribute to the development and progression of vascular inflammatory conditions via the M1 polarization. The elevated levels of advanced glycation end products (AGEs) in diabetic environment lead to severe inflammation, and the release of pro-inflammatory mediators. This shifts the balance towards the pro-inflammatory state of monocytes.

OBJECTIVE

The current study was aimed to determine the antiglycation activity of 1,2,4-triazine derivatives, and study of their molecular basis in regulating the AGEs-mediated inflammatory responses in THP-1 monocytes.

METHODS

Primarily, the antiglycation activity of a series of 1,2,4-triazine derivatives was evaluated against MGO-AGEs in vitro. The toxicity of antiglycation compounds was determined by a metabolic assay, using human hepatocyte (HepG2) and monocyte (THP-1) cell lines. DCFH-DA probe was used to evaluate the antioxidant potential of the compounds. Immunocytochemistry, Western blotting, and ELISA techniques were employed to determine the levels of pro-inflammatory markers (NF-κB, RAGE, COX-1, COX-2, and PGE2) in THP-1 monocytes under in-vitro hyperglycemic conditions.

RESULTS

Results indicate that the triazine derivatives 22, and 23 were the most potent antiglycation agents among the entire series, while non-toxic to HepG2, and THP-1 cells. Both compounds inhibited the AGEs-induced upstream and downstream signaling of NADPH oxidase and inflammatory mediators p38 and NF-κβ, respectively, in THP-1 monocytes. They also inhibited the induction of COX-2 and its product PGE2 by suppressing AGE-RAGE interactions. Moreover, compounds 22, and 23 reversed the AGEs-mediated suppression of COX-1 in THP-1 monocytes.

CONCLUSION

In conclusion, 1,2,4-triazine derivatives 22, and 23 have the potential to suppress inflammatory responses under the diabetic environment through AGE-RAGE-NF-κβ/p38 nexus in THP-1 monocytes. These findings identify triazines 22, and 23 as compelling candidates for drug development, potentially beneficial for the diabetic patients with an elevated risk of vascular complications, such as atherosclerosis.

Formation and kinetic analysis of AGEs in Pacific white shrimp during frying

Advanced glycation end products (AGEs) are complex and heterogeneous compounds closely associated with various chronic diseases. The changes in Nε-carboxymethyllysine (CML), Nε-carboxyethyllysine (CEL), Nε-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1), and fluorescent AGEs (F-AGEs) in fried shrimp during frying (170 °C, 0-210 s) were described by kinetic models. Besides,the correlations between AGEs contents and physicochemical indicators were analyzed to reveal their intrinsic relationship. Results showed that the changes of four AGEs contents followed the zero-order kinetic, and their rate constants were ranked as kCML < kCEL ≈ kMG-H1 < kF-AGEs. Oil content and lipid oxidation were critical factors that affected the AGEs levels of the surface layer. Protein content and Maillard reaction were major factors in enhancing the CML and CEL levels of the interior layer. Furthermore, the impact of temperature on the generation of CML and CEL was greater than that of MG-H1 and F-AGEs.

Toxic AGEs (TAGE) Cause Lifestyle-Related Diseases

Advanced glycation end-products (AGEs) play a role in the onset/progression of lifestyle-related diseases (LSRD), suggesting that the suppression of AGE-induced effects can be exploited to prevent and treat LSRD. However, AGEs have a variety of structures with different biological effects. Glyceraldehyde (GA) is an intermediate of glucose, and fructose metabolism and GA-derived AGEs (GA-AGEs) have been associated with LSRD, leading to the concept of toxic AGEs (TAGE). Elevated blood TAGE levels have been implicated in the onset/progression of LSRD; therefore, the measurement of TAGE levels may enable disease prediction at an early stage. Moreover, recent studies have revealed the structures and degradation pathways of TAGE. Herein, we provide an overview of the research on TAGE. The TAGE theory provides novel insights into LSRD and is expected to elucidate new targets for many diseases.

Anhydrous microwave synthesis as efficient method for obtaining model advanced glycation end-products

Introduction

Advanced glycation end-products (AGEs) are capable of stimulating oxidative stress and inflammation. This study investigates the synthesis of medium crosslinked AGEs (the most optimal form of AGEs because of soluble in water, used in many assays as markers) and their biochemical properties.

Methods

One of model protein-myoglobin from horse heart muscle (MB) and a chosen respective glycation factor - D-melibiose (mel), acrolein (ACR), D-glucose (glc), 4-hydroksynonenal (4HNE), trans-2-nonenal (T2N), methylglyoxal (MGO) - were subjected to high temperature water synthesis (HTWS) and high temperature microwave synthesis in anhydrous conditions (HTMS). The syntheses were deliberately carried out in two different conditions to check whether adding an additional energy source (microwaves) while lowering the temperature and shortening the reaction time would allow for more effective obtaining of medium-cross-linked AGEs, monitored with SDS-PAGE. Products were analyzed using fluorescence measurements, Enzyme-Linked Immunosorbent Assay (ELISA) and immunoblotting tests and electrophoretic mobility shift assay to evaluate their ability to activate nuclear factor kappa-light-chain-enhancer (NF-κB).

Results

Medium cross-linked AGEs were more efficiently obtained in HTMS. Fluorescence was high for MB-ACR, MB-T2N and MB-glc products. Anti-MAGE antibodies showed reactivity towards MB-mels of HTMS and HTWS, and the MB-4HNEs from HTMS. HTWS products, apart from MB-ACR, did not activate NF-κB, whereas MB-ACR, MB-4HNE, MB-mel, and MB-T2N products of HTMS strongly activated this factor that indicates their strong pro-inflammatory properties.

Conclusion

HTMS is a fast and efficient method of synthesizing medium cross-linked AGEs.

Dietary Restriction of Advanced Glycation End-Products (AGEs) in Patients with Diabetes: A Systematic Review of Randomized Controlled Trials

Advanced Glycation End Products (AGEs) are formed through non-enzymatic reactions between reducing sugars and proteins, nucleic acids or lipids (for example through hyperoxidation). In diabetes, elevated glucose levels provide more substrate for AGEs formation. AGEs can also be ingested through the diet from foods cooked at high temperatures, or containing much sugar. The present work aimed to review all published randomized controlled trials (RCT) on low-dietary AGE (L-dAGEs) interventions in patients with diabetes. Pubmed, Scopus and Cochrane databases were searched (until 29 February 2024) with appropriate keywords (inclusion criteria: RCT, patients with diabetes, age > 18 years, outcomes related to inflammation, glucose, and lipids; exclusion criteria: non-RCTs, case-series, case reports and Letter to the Editor, or animal studies). The present review was registered to the Open Science Framework (OSF). From 7091 studies, seven were ultimately included. Bias was assessed with the updated Cochrane Risk of Bias tool. A reduction in circulating AGEs was documented in 3/3 studies. No particular differences were documented in glycemic parameters after a L-dAGEs diet. Reductions in glucose levels were observed in one out of six studies (1/6), while HbA1c and HOMA did not change in any study (0/6 and 0/3, correspondingly). Lipid profile also changed in one out of four studies (1/4). More consistent results were observed for oxidative stress (beneficial effects in 3/3 studies) and inflammatory markers (beneficial effects in 4/4 studies). Other athero-protective effects, such as adiponectin increases, were reported. Limitations included the small sample size and the fact that dietary and physical activity habits were not considered in most studies. In conclusion, a L-dAGEs pattern may minimize AGEs accumulation and have beneficial effects on oxidative stress and inflammation indices, while its effects on glycemic and lipemic parameters are inconsistent and modest in patients with diabetes.

Impact of quinoa and food processing on gastrointestinal health: a narrative review

Due to exceptional nutritional quality, quinoa is an ideal candidate to solve food insecurity in many countries. Quinoa's profile of polyphenols, essential amino acids, and lipids make it ideal for digestive health. How the nutrient profile and bioavailability of quinoa metabolites differs across cooking methods such as heat, pressure, and time employed has yet to be elucidated. The objective of this review is to compile available research pertaining to the impact of various cooking methods on quinoa's nutritional properties with specific emphasis on how those properties affect gut health. Replacing small percentages of wheat flour with quinoa flour in baked bread increases the antioxidant activity, essential amino acids, fiber, minerals, and polyphenols. Extruding quinoa flour reduces amino acid, lipid, and polyphenol content of the raw seed, however direct quinoa and cereal grain extrudate comparisons are absent. Boiling quinoa leads to an increase of dietary fiber as well as exceptional retention of amino acids, lipids, and polyphenols. Baking and extruding with quinoa flour results in less optimal texture due to higher density, however minor substitutions can retain acceptable texture and even improve taste. Future research on quinoa's substitution in common processing methods will create equally desirable, yet more nutritious food products.

Effects of myricetin and its derivatives on nonenzymatic glycation: A mechanism study based on proteomic modification and fluorescence spectroscopy analysis

Myricetin and its derivatives, myricitrin and dihydromyricetin, are flavonoids widely presented in foods and phytomedicine that possess tremendous health potential. In this study, we compared the antiglycation activity of myricetin and its derivatives, then investigated the underlying mechanism using proteomic modification and fluorescence spectroscopy analysis. All three compounds exhibited thorough inhibition on nonenzymatic glycation process, with the inhibitory effects on AGEs reaching 85% at 40 μmol/L. They effectively protected bovine serum albumin (BSA) structure by inhibiting protein oxidation, preventing the conversion from α-helix to β-sheet, and reducing amyloid-like cross-β structure formation. Among the three compounds, myricetin showed a predominant antiglycation activity. Proteomic analysis identified the early glycated sites that were protected by myricetin, including lysine K235, 256, 336, 421, 420, 489, etc. Additionally, fluorescence spectroscopy revealed spontaneous interactions between BSA and myricetin. Overall, myricetin holds promise as an antiglycation agent in both the food and drug industries.

Cyclic Continuous Glycation Enhanced Dispersibility of Myofibrillar Protein: Reaction Efficiency and Sites Modification

Reaction efficiency in glycation lacks sufficient attention, leading to the waste of process costs. Cyclic continuous glycation (CCG) is an effective approach to accelerate covalent binding between myofibrillar protein (MP) and glucose. This study elucidated that CCG promoted the exposure of reactive glycated sites in MP with full unfolding of secondary and tertiary structures. Notably, the glycation rate was significantly increased by 65.43%. Physicochemical properties indicated that MP-glucose conjugates with high graft degree exhibited favorable solubility, dispersibility, and thermal stability. Furthermore, proteomics was applied to reveal the glycated sites and products in glycoconjugates of MP. Glycation preferentially acted on the tails of the myosin heavy chain. The glucosylation modification on the head region was enhanced by CCG contributing to the inhibition of the head-head interaction. Overall, this study systematically clarifies the mechanism of CCG, providing a theoretical basis for the application of glycation in innovative meat products.

Development and standardization of spectrophotometric assay for quantification of thermal hydrolysis-origin melanoidins and its implication in antioxidant activity evaluation

Melanoidins are brown recalcitrant polymers originating from the thermal hydrolysis pretreatment (THP) of organic solid waste (OSW). Owing to their various formation pathways and complex structures, there is currently no reliable method to quantify melanoidins. In this study, a spectrophotometric method was developed to determine melanoidins concentration in different OSW. Three typical model Maillard reaction systems (glucose-glycine, glucose/fructose-20 amino acids, and dextran-bovine serum albumin) were used to acquire the characteristic peaks and establish standard curves. The results showed that a standard curve using glucose/fructose-20 amino acids model melanoidins at 280 nm was the optimal quantification method, because it had the best correlation with the physicochemical indicators of melanoidins and semi-quantification results calculated by excitation-emission matrix fluorescence. In addition, the applicability of the proposed method was evaluated using multiple real melanoidins samples extracted from thermally pretreated OSW under different THP conditions and food-derived melanoidins as well, demonstrating its validity and advantages. This study is the first to provide a simple, effective, and accurate method for quantifying THP-origin melanoidins from different sources. Remarkably, as a specific and important application scenario, the proposed quantification method was employed to investigate the concentration dependence of melanoidins antioxidation in thermally pretreated OSW.

Computational study on the Maillard reactions of glucose and galactose with lysine

CONTEXT

Milk has nutrient-rich but thermal sensitive matrix that undergoes varying degrees of Maillard reaction (MR) at heating conditions. The MR mainly occurs between lysine residues (Lys) and lactose composed of glucose (Glc) and galactose (Gal), which are abundantly sourced from dairy products. In the present study, the MRs of Glc and Gal with Lys at the initial and intermediate stages have been investigated theoretically using density functional theory (DFT) to simulate the gaseous and aqueous phases. Reaction mechanisms have been proposed, and relative energy changes of different steps were calculated according to the total mass balance. The calculations reveal that both Nα- and Nε-amine groups of Lys can react with the carbonyl functional group of Glc and Gal with the similar potential energy profiles, and Gal is more reactive than Glc. However, the barrier in Nε-channel is lower than in Nα-channel, indicating a faster reaction rate through the former channel compared with the latter. The 5-hydroxymethyl-2-furfural (HMF) and derivative are formed under 3-deoxysone route in the intermediate stage. The calculation results are helpful for proposing a reasonable MR mechanism and suggesting possible control methods of the MRs.

METHODS

In this study, different levels of DFT calculations have been conducted to investigate the mechanisms and favorability of generating MR products in Glc-Lys and Gal-Lys models at initial and intermediate stages in the gaseous and aqueous conditions. In order to elucidate the molecular models from the perspectives of chemistry and geometry, DFT calculations were performed by the mean of B3LYP functional at basis sets of 6-311 +  + G (d, p) and 6-311 +  + G (2df, 2p) with optional solvation settings. To examine the solvation effect, the study further constructed models with solvent H2O and calculated in wB97XD functional with 6-31 + G (d) basis set. All computations were carried out Gaussian 09 suite of quantum chemistry software.

Inhibitory effect of homemade hawthorn vinegar-based marinade on Nε-(carboxymethyl)lysine and Nε-(carboxyethyl)lysine formation in beef tenderloins

In this study, the inhibitory effects of homemade hawthorn vinegar-based marinade on the formation of Nε-(carboxymethyl) lysine (CML) and Nε-(carboxyethyl) lysine (CEL) during the cooking of beef tenderloins investigated. Additionally, the goal was to determine the bioactive compounds present in hawthorn vinegar that could contribute to these effects, both quantitatively and qualitatively. For this purpose, hawthorn vinegar was first produced from hawthorn fruit and characterized. Then, beef tenderloins were marinated at two different concentrations (25% and 50%) and three different marination times (2, 6 and 24 h) and cooked in a airfryer at 200 °C for 12 min. After the cooking process, analyses were conducted for CML, CEL, thiobarbituric acid reactive substances (TBARS), sensory and color. Hawthorn vinegar was found to have high phytochemical and bioactivity properties. It was found that hawthorn vinegar significantly altered the color properties (L*, a*, and b*) of raw beef tenderloin samples (P < 0.05). The marinating process did not adversely affect the sensory properties of the beef tenderloin, other than odour, and even improved its texture and appearance. Increasing the marination concentration and time significantly inhibited CML and CEL formation (P < 0.05), marinating the meat for 24 h reduced CML formation from 13.75 μg/g to 2.5 μg/g, while CEL formation decreased from 17.58 μg/g to 16.63 μg/g. Although CEL was inhibited at low levels during marination, it remained stable. In conclusion, this study showed that hawthorn vinegar contains bioactive compounds that significantly inhibit the formation of CML and stabilize the formation of CEL.

Glyoxal and methylglyoxal formation in chocolate and their bioaccessibility

The objective of this study was to assess the effects of simulated digestion on the formation of α-dicarbonyl compounds (α-DCs) in chocolates. For that purpose, the concentrations of glyoxal and methylglyoxal in chocolates were determined through High-Performance Liquid Chromatography (HPLC) analysis before and after in vitro digestion. The initial concentrations ranged from 0.0 and 228.2 µg/100 g, and 0.0 and 555.1 for glyoxal and methylglyoxal, respectively. Following digestion, there was a significant increase in both glyoxal and methylglyoxal levels, reaching up to 1804 % and 859 %, respectively. The findings indicate that digestive system conditions facilitate the formation of advanced glycation end product (AGE) precursors. Also, glyoxal and methylglyoxal levels were found to be low in chocolate samples containing dark chocolate. In contrast, they were found to be high in samples containing hazelnuts, almonds, pistache, and milk. Further studies should focus on α-DCs formation under digestive system conditions, including the colon, to determine the effects of gut microbiota.

The Maillard reactions: Pathways, consequences, and control

The century old Maillard reactions continue to draw the interest of researchers in the fields of Food Science and Technology, and Health and Medical Sciences. This chapter seeks to simplify and update this highly complicated, multifaceted topic. The simple nucleophilic attack of an amine onto a carbonyl group gives rise to a series of parallel and subsequent reactions, occurring simultaneously, resulting into a vast array of low and high mass compounds. Recent research has focused on: (1) the formation and transformation of α-dicarbonyl compounds, highly reactive intermediates which are essential in the development of the desired color and flavor of foods, but also lead to the production of the detrimental advanced glycation end products (AGEs); (2) elucidation of the structures of melanoidins in different foods and their beneficial effects on human health; and (3) harmful effects of AGEs on human health. Considering that MRs have both positive and negative consequences, their control to accentuate the former and to mitigate the latter, is also being conscientiously investigated with the use of modern techniques and technology.

Proteomics-based identification of biomarkers reflecting endogenous and exogenous exposure to the advanced glycation end product precursor methylglyoxal in SH-SY5Y human neuroblastoma cells

Methylglyoxal (MGO), a highly reactive precursor of advanced glycation end products, is endogenously produced and prevalent in various food products. This study aimed to characterize protein modifications in SH-SY5Y human neuroblastoma cells induced by MGO and identify potential biomarkers for its exposure and toxicity. A shot-gun proteomic analysis was applied to characterize protein modifications in cells incubated with and without exogenous MGO. Seventy-seven proteins were identified as highly susceptible to MGO modification, among which eight, including vimentin and histone H2B type 2-F, showing concentration-dependent modifications by externally added MGO, were defined as biomarkers for exogenous MGO exposure. Remarkably, up to 10 modification sites were identified on vimentin. Myosin light polypeptide 6 emerged as a biomarker for MGO toxicity, with modifications exclusively observed under cytotoxic MGO levels. Additionally, proteins like serine/threonine-protein kinase SIK2 and calcyphosin, exhibiting comparable or even higher modification levels in control compared to exogenous MGO-treated cells, were defined as biomarkers for endogenous exposure. Bioinformatics analysis revealed that motor proteins, cytoskeleton components, and glycolysis proteins were overrepresented among those highly susceptible to MGO modification. These results identify biomarkers for both endogenous and exogenous MGO exposure and provide insights into the cellular effects of endogenously formed versus externally added MGO.

Inhibition of polyphenols on Maillard reaction products and their induction of related diseases: A comprehensive review

BACKGROUND

Food products undergo a pronounced Maillard reaction (MR) during the cooking process, leading to the generation of substantial quantities of Maillard reaction products (MRPs). Within this category, advanced glycation end products (AGEs), acrylamide (AA), and heterocyclic amines (HAs) have been implicated as potential risk factors associated with the development of diseases.

PURPOSE

To explore the effects of polyphenols, a class of bioactive compounds found in plants, on the inhibition of MRPs and related diseases. Previous research has mainly focused on their interactions with proteins and their effects on the gastrointestinal tract and other diseases, while fewer studies have examined their inhibitory effects on MRPs. The aim is to offer a scientific reference for future research investigating the inhibitory role of polyphenols in the MR.

METHODS

The databases PubMed, Embase, Web of Science and The Cochrane Library were searched for appropriate research.

RESULTS

Polyphenols have the potential to inhibit the formation of harmful MRPs and prevent related diseases. The inhibition of MRPs by polyphenols primarily occurs through the following mechanisms: trapping α-dicarbonyl compounds, scavenging free radicals, chelating metal ions, and preserving protein structure. Simultaneously, polyphenols exhibit the ability to impede the onset and progression of related diseases such as diabetes, atherosclerosis, cancer, and Alzheimer's disease through diverse pathways.

CONCLUSION

This review presents that inhibition of polyphenols on Maillard reaction products and their induction of related diseases. Further research is imperative to enhance our comprehension of additional pathways affected by polyphenols and to fully uncover their potential application value in inhibiting MRPs.

Exploring Maternal Diet-Epigenetic-Gut Microbiome Crosstalk as an Intervention Strategy to Counter Early Obesity Programming

Alterations in a mother's metabolism and endocrine system, due to unbalanced nutrition, may increase the risk of both metabolic and non-metabolic disorders in the offspring's childhood and adulthood. The risk of obesity in the offspring can be determined by the interplay between maternal nutrition and lifestyle, intrauterine environment, epigenetic modifications, and early postnatal factors. Several studies have indicated that the fetal bowel begins to colonize before birth and that, during birth and nursing, the gut microbiota continues to change. The mother's gut microbiota is primarily transferred to the fetus through maternal nutrition and the environment. In this way, it is able to impact the establishment of the early fetal and neonatal microbiome, resulting in epigenetic signatures that can possibly predispose the offspring to the development of obesity in later life. However, antioxidants and exercise in the mother have been shown to improve the offspring's metabolism, with improvements in leptin, triglycerides, adiponectin, and insulin resistance, as well as in the fetal birth weight through epigenetic mechanisms. Therefore, in this extensive literature review, we aimed to investigate the relationship between maternal diet, epigenetics, and gut microbiota in order to expand on current knowledge and identify novel potential preventative strategies for lowering the risk of obesity in children and adults.

Association of four differently processed diets with plasma and urine advanced glycation end products and serum soluble receptor for advanced glycation end products concentration in healthy dogs

Advanced glycation end products (AGEs), formed via the Maillard reaction (MR) during processing of foods, have been implicated in inflammatory and degenerative diseases in human beings. Cellular damage is primarily caused by AGE binding with the receptor for AGEs (RAGE) on cell membranes. An isoform of RAGE, soluble RAGE (sRAGE), acts as a decoy receptor binding circulating AGEs preventing cellular activation. Pet food manufacturing involves processing methods similar to human food processing that may increase dietary AGEs (dAGEs). We hypothesized that diet, plasma and urine AGEs, and serum sRAGE concentrations would differ between thermally processed diets. This study examined the association of four differently processed diets: ultra-processed canned wet food (WF); ultra-processed dry food (DF); moderately processed air-dried food (ADF) and minimally processed mildly cooked food (MF) on total plasma levels of the AGEs, carboxymethyllysine (CML), carboxyethyllysine (CEL), methylglyoxal hydroimidazolone-1, glyoxal hydroimidazolone-1, argpyrimidine, urine CML, CEL and lysinoalanine, and serum sRAGE concentration. Ultra-high-performance liquid chromatography-tandem mass spectrometry was used to measure AGEs. sRAGE concentration was measured using a commercial canine-specific enzyme-linked immunosorbent assay kit. Total dAGEs (mg/100 kcal as fed) were higher in WF than in other diets. Plasma total AGEs (nM/50 μL) were significantly higher with WF, with no difference found between DF, ADF, and MF; however, ADF was significantly higher than MF. Urine CML (nmol AGEs/mmol creatinine) was significantly higher with DF than with WF and MF. There were no significant differences in total urine AGEs or serum sRAGE concentration between diets. In conclusion, different methods of processing pet foods are associated with varied quantities of AGEs influencing total plasma AGE concentration in healthy dogs. Serum sRAGE concentration did not vary across diets but differences in total AGE/sRAGE ratio were observed between MF and WF and, ADF and DF.

Potential inhibitory effect of highland barley protein hydrolysates on the formation of advanced glycation end-products (AGEs): A mechanism study

Advanced glycation end products (AGEs) can be caused during a glycoxidation reaction. This reaction is associated with complications of diabetes and the consequences of health problems. Therefore, we are exploring the prohibitory effect of highland barley protein hydrolysates (HBPHs) on AGE formation. Herein, first extracted the protein from highland barley with various pH conditions and then hydrolyzed using four different proteolytic enzymes (flavourzyme, trypsin, papain, pepsin) under different degrees of hydrolysis. We assessed three degrees of hydrolysates (lowest, middle, highest) of enzymes used to characterize the antioxidant activity and physicochemical properties. Among all the hydrolysates, flavourzyme-treated hydrolysates F-1, F-2, and F-3 indicated the high ability to scavenge DPPH (IC50 values of 0.97 %, 0.63 %, and 0.90 %), structural and functional properties. Finally, the inhibitory effect of the most active hydrolysates F-1, F-2, and F-3 against the AGEs formation was evaluated in multiple glucose-glycated bovine serum albumin (BSA) systems. Additionally, in a BSA system, F-3 exhibited the strong antiglycation activity, effectively suppressed the non-fluorescent AGE (CML), and the fructosamine level. Moreover, it decreased carbonyl compounds while also preventing the loss of thiol groups. Our results would be beneficial in the application of the food industry as a potential antiglycation agent for several chronic diseases.

Ultra-processed foods - a scoping review for Nordic Nutrition Recommendations 2023

Ultra-processed foods (UPFs) are increasingly consumed worldwide and have been linked to several chronic diseases. This paper aims to describe the totality of the available evidence regarding UPFs in relation to health-related outcomes as a basis for setting food-based dietary guidelines for the Nordic Nutrition Recommendations 2023. Systematic literature searches were conducted to identify systematic reviews, meta-analyses, randomized controlled trials (RCTs), and prospective cohort studies examining the association between UPF intake and non-communicable diseases or mortality. A total of 12 systematic reviews (including five meta-analyses) and 44 original research studies (43 prospective cohort studies and one RCT) were included. All original research studies were deemed to be of good methodological quality. The current evidence supports that greater consumption of UPFs is associated with weight gain and increased risk of obesity, cardiovascular disease, type 2 diabetes, and all-cause mortality. The available literature also supports an association between UPFs and hypertension, cancer, and depression; however, the limited number of studies and subjects investigated preclude strong conclusions. Due to the highly diverse nature of UPFs, additional studies are warranted, with special emphasis on disentangling mediating mechanisms, whether nutritional or non-nutrient based. Nevertheless, the available evidence regarding UPFs in relation to weight gain, CVD, type 2 diabetes, and all-cause mortality is considered strong enough to support dietary recommendations to limit their consumption.

Scavenging Glyoxal and Methylglyoxal by Synephrine and Neohesperidin from Flowers of Citrus aurantium L. var. amara Engl. in Mice and Humans

There is considerable research evidence that α-dicarbonyl compounds, including glyoxal (GO) and methylglyoxal (MGO), are closely related to many chronic diseases. In this work, after comparison of the capture capacity, reaction pathway, and reaction rate of synephrine (SYN) and neohesperidin (NEO) on GO/MGO in vitro, experimental mice were administrated with SYN and NEO alone and in combination. Quantitative data from UHPLC-QQQ-MS/MS revealed that SYN/NEO/HES (hesperetin, the metabolite of NEO) could form the GO/MGO-adducts in mice (except SYN-MGO), and the levels of GO/MGO-adducts in mouse urine and fecal samples were dose-dependent. Moreover, SYN and NEO had a synergistic scavenging effect on GO in vivo by promoting each other to form more GO adducts, while SYN could promote NEO to form more MGO-adducts, although it could not form MGO-adducts. Additionally, human experiments showed that the GO/MGO-adducts of SYN/NEO/HES found in mice were also detected in human urine and fecal samples after drinking flowers of Citrus aurantium L. var. amara Engl. (FCAVA) tea using UHPLC-QTOF-MS/MS. These findings provide a novel strategy to reduce endogenous GO/MGO via the consumption of dietary FCAVA rich in SYN and NEO.

Lysozyme amyloid fibril-chitosan double network hydrogel: Preparation, characterization, and application on inhibition of Nε-(carboxyethyl)lysine

Nε-(carboxyethyl)lysine (CML), a typical advanced glycosylation end product produced during the processing of meat under high temperature, poses health risks. Active substances like polyphenols are known to inhibit the formation of harmful products during the processing of food. In this study, our objective was to prepare a double network hydrogel (DN) loaded with gallic acid using amyloid fibers and chitosan as a rigid and flexible network, respectively. The network as well as the interactions between the two networks were observed and analyzed. Chitosan concentration was the key factor regulating the structure and properties of the DN. At a chitosan concentration of 0.7%wt, the structure of DN became dense and its mechanical properties were improved, with the loading capacity and loading efficiency being increased by 143.79 % and 128.21 %, compared with those of amyloid fibril alone. Furthermore, the digestibility of gallic acid in simulated intestinal fluid was increased by 215.10 %. Moreover, adding DN to the beef patties effectively inhibited the formation of CML in a dose-response dependent manner. Addition of 3 wt% DN resulted in the inhibitory rate of CML in roast beef patties reaching a high 73.09 %. The quality and palatability of beef patties were improved. These findings suggest that DN shows great potential as an application that may be utilized to deliver active substances aimed at inhibiting CML in the meat processing industry.

Effects of different reducing carbohydrate types on the physicochemical characteristics of infant formula food stored for special medical purposes

The formula of food for special medical purpose has a direct impact on physicochemical stability, especially in hot climes and high temperature transport storage environments. An accelerated test (50 °C for 7 weeks) was used to analyze the mechanism of the physicochemical instability of formula A with lactose and maltodextrin, and formula B with maltodextrin. Deep dents and wrinkles were observed on the surface of the formula B, and more fat globules covered the surface of formula A particles after storage for a long time. Significantly higher amounts of furosine and Nε-carboxymethl-l-lysine (CML) were formed and the loss of available lysine was greater in formula A than in formula B. No significant difference was observed in lipid oxidation indicators between the two formulas. The results of this research demonstrated lactose was more active than maltodextrin and led to physicochemical instability.

Glycation of tilapia protein hydrolysate decreases cellular antioxidant activity upon in vitro gastrointestinal digestion

Changes in structural characteristics and antioxidant activity of tilapia hydrolysate glycated with glucose, fructose, or xylose at 90 °C for 12 h, and following in vitro gastrointestinal (GI) digestion were investigated. Fourier-transformed infrared (FTIR) band between 1,800 and 1,400 cm-1 confirmed the structural modifications of hydrolysate under glycations. Glycation drastically increased ATBS · + and ONOO - scavenging activities (p < 0.05) as well as ferric-reducing antioxidant power (FRAP). Xylose was the most effective sugar for glycation, yielding the highest chemical antioxidant activities (p < 0.05). However, glycated hydrolysates exhibited lower cellular antioxidant activity (CAA) on HepG2 cell when compared to hydrolysates. The extensive glycation of hydrolysates resulted in lower GI digestibility as confirmed by the FTIR spectra of C[bond, double bond]O, C-N, N-H, C-C, C-O, and C-H stretching vibrations. Glycation of tilapia hydrolysates only improved chemical antioxidant activities, but alleviated CAA, especially upon simulated GI digestion.

Scavenging Glyoxal and Methylglyoxal by Synephrine Alone or in Combination with Neohesperidin at High Temperatures

α-Dicarbonyl compounds, such as glyoxal (GO) and methylglyoxal (MGO), are a series of chemical hazards that exist in vivo and in vitro, posing a threat to human health. We aimed to explore the scavenging effects on GO/MGO by synephrine (SYN) alone or in combination with neohesperidin (NEO). First, through LC-MS/MS, we confirmed that both SYN and NEO could effectively remove GO and form GO adducts, while NEO could also clear MGO by forming MGO adducts, and its ability to clear MGO was stronger than that of GO. Second, a synergistic inhibitory effect on GO was found when SYN and NEO were used in combination by using the Chou-Talalay method; on the other hand, SYN could promote NEO to clear more MGO, although SYN could not capture MGO. Third, after synthesizing four GO/MGO-adducts (SYN-GO-1, SYN-GO-3, NEO-GO-7, and NEO-MGO-2) and identifying their structure through NMR, strict correlations between the GO/MGO-adducts and the GO/MGO-clearance rate were found when using SYN and NEO alone or in combination. Furthermore, it was inferred that the synergistic effect between SYN and NEO stems from their mutual promotion in capturing more GO by the quantitative analysis of the adducts in the combined model. Finally, a study was conducted on flowers of Citrus aurantium L. var. amara Engl. (FCAVA, an edible tea) rich in SYN and NEO, which could serve as an effective GO and MGO scavenger in the presence of both GO and MGO. Therefore, our study provided well-defined evidence that SYN and NEO, alone or in combination, could efficiently scavenge GO/MGO at high temperatures, whether in the pure form or located in FCAVA.