UV analysis of Amadori-glycated phosphatidylethanolamine in foods and biological samples

Abstract

Maillard reactions are among the most important of the chemical and oxidative changes occurring in food and biological samples that contribute to food deterioration and to the pathophysiology of human disease. Although the association of lipid glycation with this process has recently been shown, the number of lipid glycation products in food and biological materials has not been clear. In this study, we synthesized the Amadori products derived from the glycation of phosphatidylethanolamine (PE), i.e., Amadori-PEs. Dioleoyl PE was incubated with glucose and lactose for 15 days, and the resultant Amadori-PEs were purified and isolated using solid phase extraction followed by HPLC. With this procedure, essentially pure ( Ͼ 98% purity) Amadori-PEs glycated with glucose (Glc-PE) and with lactose (Lac-PE) were obtained and used as standards in the subsequent studies.To determine the presence of Amadori-PEs in food and biological samples, the carbonyl group of Amadori-PEs was ultraviolet (UV)-labeled with 3-methyl-2-benzothiazolinone hydrazone, and the labeled Amadori-PEs were analyzed with normal phase HPLC-UV (318 nm). The detection limit was 4.5 ng (5 pmol) for Glc-PE and 5.3 ng (5 pmol) for Lac-PE. Among the several food samples examined, infant formula and chocolate contained a high amount of both Glc-PE and Lac-PE over wide concentration ranges, such as 1.5-112 g/g. Testing biological materials showed Amadori-PE (Glc-PE) was detectable in rat plasma. -Oak, J-H., K. Nakagawa, and T. Miyazawa. UV analysis of Amadoriglycated phosphatidylethanolamine in foods and biological samples.

Amadori-glycated phosphatidylethanolamine enhances the physical stability and selective targeting ability of liposomes

“…The synthesis efficiency of glycated PE was determined by HPLC-MS/MS to be greater than 50% for both GPE and LPE. These results are consistent with previous studies conducted in our laboratory [11,12]. On the other hand, liposomes containing glycated PE were found to exhibit a significant reduction in negative zeta potential, compared with liposomes containing non-glycated PE (figure 4c).…”

“…Glycated PE was prepared according to the method previously described by Miyazawa et al [11,12]. In this glycation reaction, the amino group of PE and the hydroxyl group of the saccharide react via a dehydration condensation reaction to form an unstable ring-opening compound known as a Schiff base (-C = N-).…”

“…Unlike PE, glycated PE contains a saccharide moiety in its chemical structure. We previously reported a method to synthesize glycated PE standards with high purity from saccharides and PE [11,12]. We hypothesized that liposomes prepared from mixtures of PC and glycated PE should exhibit enhanced membrane fusion and cellular uptake capacities due to the presence of the PE sites, while the presence of the saccharide moiety should allow for selective targeting of cells that highly express GLUTs on their membranes.…”

Metabolomic signatures for liver tissue and cecum contents in high-fat diet-induced obese mice based on UHPLC-Q-TOF/MS

“…Together with PC, PS, PI, PE represents the backbone of most biological membranes. Phosphoethanolamines in food break down to form phosphoethanolamine-linked amadori products, which act as a part of the Maillard reaction [ 36 ]. These products accelerate membrane lipid peroxidation and cause oxidative stress on cells exposed to them [ 37 ].…”

A preliminary study on the formation pathways of glycated phosphatidylethanolamine of food rich in phospholipid during the heat-processing

“… 4–11 To date, Amadori-glycated phosphatidylethanolamine (Amadori-PE) has been detected in a number of foodstuffs. 8,12 Oak et al examined Amadori-PE presence in several food samples, among which infant formula, chocolate, mayonnaise and soybean milk, found to contain a high amount of Amadori-PE. 8 Utzmann et al found PE-linked glycated products in model systems as well as in spray-dried egg yolk.…”