Robust Detection of Advanced Glycation Endproducts in Milk Powder Using Ultrahigh Performance Liquid Chromatography Tandem Mass Spectrometry (UHPLC-MS/MS)

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.

Formation of advanced glycation end products in glucose-amino acid models of Maillard reaction under dry- and wet-heating conditions

BACKGROUND

Advanced glycation end products (AGEs) are compounds formed by non-enzymatic processes in the Maillard reaction and can cause various chronic diseases. This study explores the AGE formation process in a glucose-amino acid system under both wet- and dry-heating conditions, and analyzes the effect of cysteine in AGE formation.

RESULTS

Under wet-heating conditions, Nε-carboxymethyllysine (CML) and Nε-carboxyethyllysine (CEL) concentrations rose for the initial 90 min and subsequently declined after 120 min; after 90 min of heating, the maximum yields in the absence of cysteine were 1151.04 ± 14.01 and 3386.90 ± 26.55 ng mL-1, respectively. The concentration of pyrraline (Pyr) increased after 30 min and then decreased after 60 min with a maximum yield of 777.68 ± 23.36 ng mL-1. However, in dry-heating models, the AGE concentrations consistently increased with increasing heating time; the maximum yields for CML, CEL and Pyr were 468.66 ± 10.96, 1993.57 ± 14.81 and 1085.74 ± 58.06 ng mL-1, respectively. The addition of cysteine showed an inhibitory effect on AGE formation, especially for Pyr in the dry-heating model, with inhibition rates ranging from 17.14% to 95.60%.

CONCLUSION

Although wet-heating models produced more CML and CEL, they produced less Pyr than dry-heating models. The AGE formation in wet-heating models positively correlated with the reaction rate; however, the dry-heating reaction demonstrated a more complex relationship between reaction rate and reaction protocol. Moreover, cysteine exhibited a significant inhibitory effect on AGE production, and the degree of inhibition was proportional to the cysteine concentration. This study provides important insights into the mechanisms for AGE formation under various heating conditions, such as those representing baking (dry-heating) and steaming conditions (wet-heating). © 2024 Society of Chemical Industry.

Recent Trends in Advanced Glycation End Products in Foods: Formation, Toxicity, and Innovative Strategies for Extraction, Detection, and Inhibition

Advanced glycation end products (AGEs) are produced in foods during their thermal treatment through routes like the Maillard reaction. They have been linked to various health issues such as diabetes, neurodegenerative disorders, and cardiovascular diseases. There are multiple pathways through which AGEs can form in foods and the body. Therefore, this review work aims to explore multiple formation pathways of AGEs to gain insights into their generation mechanisms. Furthermore, this review work has analyzed the recent trends in the detection and inhibition of AGEs in food matrices. It can be highlighted, based on the surveyed literature, that UHPLC-Orbitrap-Q-Exactive-MS and UPLC-ESI-MS/MS can produce highly sensitive results with a low limit of detection levels for AGEs in food matrices. Moreover, various works on inhibitory agents like spices, herbs, fruits, vegetables, hydrocolloids, plasma-activated water, and probiotic bacteria were assessed for their capacity to suppress the formation of AGEs in food products and simulation models. Overall, it is essential to decrease the occurrence of AGEs in food products, and future scope might include studying the interaction of macromolecular components in food products to minimize the production of AGEs without sacrificing the organoleptic qualities of processed foods.

Simultaneous analysis of advanced glycation end products using dansyl derivatization

Herein, new pre-column derivatization based on dansylation is present to resolve analytical difficulties, such as chromatographic separation difficulty, in identifying and quantifying advanced glycation end products (AGEs) owing to their high hydrophilicity, wide variety, and structural similarity. The proposed analytical method facilitated the separation of 14 AGEs, including structural isomers. Limits of detection of 1.0-43.3 ng/mL and linear ranges of the double- or triple-digit were achieved. Intra- and inter-day precisions of 1.1-3.0% and 1.3-3.1%, respectively, were achieved for standard solutions, while those for food specimens were 1.4-11.2% and 1.7-15.7%, respectively. The matrix effect was insignificant with regard to the percent recoveries and differences between slopes for both the standard solutions and food specimens. Furthermore, the quantitation results of AGEs in foods (coffee, beer, and sausage) and glycated proteins revealed the potential applicability of the developed method in various fields of food chemistry and biochemistry.

Isotope dilution-HPLC-MS/MS to investigate the production patterns and possible pathways of free and protein-bound AGEs and 4-MI in cookies

A qualitative and quantitative method for detecting free and protein-bound advanced glycation end products (AGEs) and 4-methylimidazole (4-MI) was established using isotope dilution-HPLC-MS/MS, and successfully applied in cookies and model systems. The effects of different temperatures (160-220 °C) on the formation of free and protein-bound AGEs and 4-MI in cookies were discussed, and the possible model systems (Maillard reaction pathway 1 using wheat gluten protein + glucose + sucrose; direct addition pathway 1 using wheat gluten protein + CML/CEL/4-MI) of protein-bound AGEs and 4-MI were verified. The results showed that the contents of protein-bound CML, CEL, and 4-MI were higher than free content with a tendency of increasing first and subsequently decreasing with temperature, reaching a maximum at 200 °C in cookies. In the model systems, the levels of protein-bound CML, CEL, and 4-MI are higher than those of free CML, CEL, and 4-MI. The protein-bound CML, CEL, and 4-MI accounted for 90.73, 87.64, and 97.56% of the total amount in the model system 1, while accounting for 68.19, 59.00, and 50.96% in the model system 2, respectively. In comparison, protein-bound CML, CEL, and 4-MI could be easily generated directly by Maillard reaction.

Occurrence of dietary advanced glycation end-products in commercial cow, goat and soy protein based infant formulas

Thermal treatment is a key step during infant formula (IF) processing which causes protein glycation and formation of dietary advanced glycation end-products (dAGEs). This study aimed to evaluate the glycation degree in IF in relation to the ingredients of the formula. dAGEs concentrations have been determined by UPLC-MS/MS in a range of commercial cow-based, goat-based, and soy-based IF. Results indicated that the protein source, protein composition, and amount and type of carbohydrates determines the level of protein glycation in IFs. The investigated soy-based formula had significant higher concentrations of arginine and arginine-derived dAGEs than cow-based and goat-based formulas. IF containing hydrolyzed proteins had higher dAGEs concentrations than those containing intact proteins. Lactose-containing formula was more prone to glycation than those containing sucrose and maltodextrin. Data showed glycation degree in IF cannot be estimated by a single compound, but the complete picture of the dAGEs should be considered.

Advanced Glycation End Products: A Comprehensive Review of Their Detection and Occurrence in Food

The Maillard reaction (MR) is a complicated chemical process that has been extensively studied. Harmful chemicals known as advanced glycation end products (AGEs), with complex structures and stable chemical characteristics, are created during the final stage of the MR. AGEs can be formed both during the thermal processing of food and in the human body. The number of AGEs formed in food is much higher compared to endogenous AGEs. A direct connection exists between human health and the build-up of AGEs in the body, which can result in diseases. Therefore, it is essential to understand the content of AGEs in the food we consume. The detection methods of AGEs in food are expounded upon in this review, and the advantages, disadvantages, and application fields of these detection methods are discussed in depth. Additionally, the production of AGEs in food, their content in typical foods, and the mechanisms influencing their formation are summarized. Since AGEs are closely related to the food industry and human health, it is hoped that this review will further the detection of AGEs in food so that their content can be evaluated more conveniently and accurately.

Magnetically Controlled Nanorobots Based on Red Emissive Peptide Dots and Artificial Antibodies for Specific Recognition and Smart Scavenging of Nε-(Carboxymethyl)lysine in Dairy Products

Food-borne advanced glycation end products (AGEs) are highly related to various irreversible diseases, and N^ε-(carboxymethyl)lysine (CML) is the typical hazardous AGE. The development of feasible strategies to monitor and reduce CML exposure has become desirable to address the problems. In this work, we proposed magnetically controlled nanorobots by integrating an optosensing platform with specific recognition and binding capability, realizing specific anchoring and accurate determination as well as efficient scavenging of CML in dairy products. The artificial antibodies offered CML imprinted cavities for highly selective absorption, and the optosensing strategy was designed based on electron transfer from red emissive self-assembling peptide dots (r-SAPDs) to CML, which was responsible for the identity, response, and loading process. The r-SAPDs overcame the interference from autofluorescence, and the limit of detection was 0.29 μg L^-1, which bestowed accuracy and reliability for in situ monitoring. The selective binding process was accomplished within 20 min with an adsorption capacity of 23.2 mg g^-1. Through an external magnetic field, CML-loaded nanorobots were oriented, moved, and separated from the matrix, which enabled their scavenging effects and reusability. The fast stimuli-responsive performance and recyclability of the nanorobots provided a versatility strategy for effective detection and control of hazards in food.

Research advances of advanced glycation end products in milk and dairy products: Formation, determination, control strategy and immunometabolism via gut microbiota

Advanced glycosylation end products (AGEs) are a series of complex compounds which generate in the advanced phase of Maillard reaction, which can pose a non-negligible risk to human health. This article systematically encompasses AGEs in milk and dairy products under different processing conditions, influencing factors, inhibition mechanism and levels among the different categories of dairy products. In particular, it describes the effects of various sterilization techniques on the Maillard reaction. Different processing techniques have a significant effect on AGEs content. In addition, it clearly articulates the determination methods of AGEs and even discusses its immunometabolism via gut microbiota. It is observed that the metabolism of AGEs can affect the composition of the gut microbiota, which further has an impact on intestinal function and the gut-brain axis. This research also provides a suggestion for AGEs mitigation strategies, which are beneficial to optimize the dairy production, especially innovative processing technology application.

Comparison of metabolic fate, target organs, and microbiota interactions of free and bound dietary advanced glycation end products

Increased intake of Western diets and ultra-processed foods is accompanied by increased intake of advanced glycation end products (AGEs). AGEs can be generated exogenously in the thermal processing of food and endogenously in the human body, which associated with various chronic diseases. In food, AGEs can be divided into free and bound forms, which differ in their bioavailability, digestion, absorption, gut microbial interactions and untargeted metabolites. We summarized the measurements and contents of free and bound AGE in foods. Moreover, the ingestion, digestion, absorption, excretion, gut microbiota interactions, and metabolites and metabolic pathways between free and bound AGEs based on animal and human studies were compared. Bound AGEs were predominant in most of the selected foods, while beer and soy sauce were rich in free AGEs. Only 10%-30% of AGEs were absorbed into the systemic circulation when orally administered. The excretion of ingested free and bound AGEs was approximately 90% and 60%, respectively. Dietary free CML has a detrimental effect on gut microbiota composition, while bound AGEs have both detrimental and beneficial impacts. Free and bound dietary AGEs changed amino acid metabolism, energy metabolism and carbohydrate metabolism. And besides, bound dietary AGEs altered vitamin metabolism, and glycerolipid metabolism.