The accumulation of advanced glycation endproducts (AGEs) in the body due to glycative stress is one of the factors that contribute to the progression of aging and age-related degeneration, such as reduced tissue elasticity, inflammation, and deteriorated physical function. To suppress glycation in the body, there are measures including suppressing postprandial hyperglycemia, preventing the formation of AGEs, and decomposing and excreting AGEs. In recent years, various plant materials have been recognized for their inhibitory effects on AGE formation, and are used in health foods, supplements, and skincare products that target glycation inhibition. Polyphenols and other plant materials have been identified as components that inhibit AGE formation. On the other hand, amino acids in food are important nutrients that also play a role in maintaining muscle and health by regulating protein and lipid metabolism. However, amino acids can quickly form AGEs through glycation, so when they coexist with proteins, they can act as a substitute and subsequently prevent the glycation of proteins. In this study, we used a protein-glucose glycation model with human serum albumin (HSA) and bovine collagen Type I (COL) to investigate the inhibitory effect of amino acids (23 types) on formation of the fluorescent AGEs (F-AGEs) and pentosidine. Inhibitory effects on F-AGE formation were observed for 17 amino acids in the HSA model and 20 amino acids in the COL model. Pentosidine formation was inhibited by 22 amino acids in both the HSA and COL model. The inhibitory rates of amino acids on both F-AGE and pentosidine formation were correlated between the HSA and COL models. No correlation was observed between the F-AGE and pentosidine formation inhibitory rate in the COL model. Based on these findings, it can be speculated that since amino acids have an inhibitory effect on AGE formation, their active intake may help prevent glycation-related aging.

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Accumulation of endogenous AGEs (advanced glycation endproducts) in the body due to glycative stress is one of the factors contributing to aging and the progression of age-related degenerative diseases. Methods to control glycative stress include controlling postprandial hyperglycemia, inhibiting AGE formation, and degrading and excreting AGEs. Since there are multiple pathways for glycation in vivo, in order to prevent AGE accumulation, it is necessary to inhibit the multifactorial pathways of the glycation. From these perspectives, a combination of materials is important for inhibition of AGE formation. Previous studies have shown that amino acids inhibit the formation of fluorescent AGEs (F-AGEs) and pentosidine. In this study, we prepared mixed solutions containing either two or six amino acids, selected seven amino acids known to have inhibitory effects on AGE formation, and examined their effectiveness based on their varying inhibitory effects on F-AGE and pentosidine formation. A model in which glucose was reacted with human serum albumin or type 1 collagen was used for the experiment. The results showed that the amino acid mixture had a higher inhibition rate of pentosidine formation than F-AGE formation. Ultimately, we identified to the combination with highest rate of inhibition for both F-AGE and pentosidine formation. This amino acid mixture may inhibit pentosidine formation, thereby reducing its cross-linking potentially preventing protein denaturation and dysfunction.

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Wine has the ability to inhibit the formation of advanced glycation end products (AGEs), an attractive health function for daily glycative stress management. On the other hand, the alcohol content of wine limits its intake, even in the absence of alcohol intolerance or underlying diseases that are adversely affected by alcohol consumption. Therefore, to enable selection of wines with stronger anti-glycation effects, we evaluated the anti-glycation effects of 277 wines and examined how wine color, grape variety, producing country, and vinification method affected the anti-glycation effects of the wines. In parallel with the evaluation of anti-glycation activity, the total polyphenol content in terms of gallic acid was also determined. The results showed that there was a strong correlation between the inhibition ratio of fluorescence AGE formation and total polyphenol content in wine at various concentrations (R² = 0.736 ~ 0.863). Red wine was significantly higher in terms of total polyphenol content, but there was no significant difference between orange and red wines in terms of IC₅₀, a measure of AGE formation inhibition. On the other hand, there was no significant difference in total polyphenol content between white wine and rosé wine, but rosé wine showed a significantly lower value in IC₅₀. Analysis by grape variety showed that wines made from Saperavi generally had significantly higher total polyphenol content than other varieties, while wines made from Pinot Noir/Pinot Nero and Rkatsiteli tended to have significantly lower total polyphenol content. However, there were no significant differences in IC₅₀ among grape varieties. These suggest that while total polyphenol content is a major contributor to the antiglycation effect of wine, other factors may also contribute.

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Objectives : “Quality of sleep” plays an important role in maintaining the body`s homeostasis. Deterioration of sleep quality is related to stress and can induce various stresses in the body. The present study, an open-label trial, aimed to verify the effects of a test product, a bed mattress with a distinctive 4-layer, 3-dimensional structure, on sleep quality and the secretion of salivary oxytocin (OT). Methods : Potential research participants included 27 adults (men and postmenopausal women aged 45–64) who reported complaints about sleep quality. From the potential participants, 12 subjects, whose scores of the Pittsburgh Sleep Quality Index (PSQI-J) were six or higher, were selected (age : 54.0 ± 1.8). Test product mattresses from Nishikawa Co., Ltd. (Tokyo) were used for one week, and alternations in physical information were examined in an open trial. The open trial focused on subjective and objective symptom assessments such as Obstructive Sleep Apnea (OSA), Profile of Mood States (POMS2), and State-Trait Anxiety Inventory (STAI), as well as assessments of salivary OT and metabolites of urinary catecholamine were included. The present study was conducted with the approval of an ethics committee. Results: Regarding subjective and objective symptoms, the following showed significant improvement: in OSA, factor 1 (sleepiness upon rising), factor 2 (initiation and maintenance of sleep), factor 4 (refreshing feeling), and factor 5 (sleep duration). Scores in POM2 for feeling conditions, and STAI for trait anxiety significantly improved. No significant differences were observed in salivary and urinary OT. However, the results of the analysis separated by sex showed that salivary OT levels at wake-up time for women were significantly reduced (2.21 ± 0.25 pg/mL → 1.83 ± 0.16 pg/mL, p = 0.028) and the OT level at bedtime was higher than OT level at wake-up time (p = 0.035). Regarding catecholamine metabolites, vanillylmandelic acid (VMA) significantly increased in both total of men and women (p = 0.042) as well as women alone (p = 0.035). Conclusion: The conditions of subjects before the intervention suggested that OT secretion at wake-up time was accelerated due to responses to stress related sleep quality deterioration. However, it suggested that the usage of the test product could mitigate stresses so that OT, a stress-regulating hormone, decreased. Simultaneously, it was considered that effective stimuli recovered OT secretion capacity and OT secretion at bedtime improved. Improvement in “sleep quality” is important for alleviating mental and physiological stress and maintaining homeostasis in OT secretion.

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Subjects: Most of the biological effects of glycative stress are caused by the reaction of carbohydrate- and lipid-derived aldehydes with proteins in the body, resulting in the formation of advanced glycation end products (AGEs). These reactions are called glycation, and when AGEs are formed and accumulate in the body, they cause various disorders in tissues and cells. On the other hand, melanoidin has been reported to suppress elevated blood glucose levels, act as an antioxidant, and promote prebiotic activity (growth of bifidobacteria). Japanese people have a habit of consuming soy sauce, which is rich in AGEs and melanoidin. In this study, we examined the anti-glycation and anti-oxidation actions of ingredients in soy sauce. Methods: 13 commercial soy sauce products were used as samples. The soy sauce samples were filtered through an ultrafiltration filter with a molecular weight of 3,000 and divided into three fractions: unfiltered (fraction A), membrane filtrate (nonmelanoid fraction) (fraction B), and membrane residue (melanoidin fraction) (fraction C). After measuring fluorescent AGEs and pentosidine in the glycation reaction solution, the percentage inhibition of formation (%) or IC50 was calculated. The DPPH radical scavenging activity of the samples was determined. Glycine - Glucose melanoidin (GGM) was synthesized in the laboratory, and the melanoidin content in soy sauce was measured by absorbance (400 nm). The fluorescent AGE content in soy sauce was calculated as argpyrimidine equivalents. Results: All soy sauce samples inhibited the formation of fluorescent AGEs and pentosidine. Also, DPPH radical scavenging activity was observed. In fraction C, the IC50 of fluorescent AGEs was 3.4 times lower than that of fraction B. The DPPH radical scavenging activity of fraction C was greater than that of fractions A and B (p < 0.05). Fraction C was 2.51 times (0.36 mg/mL) more potent than GGM in inhibiting fluorescent AGE formation and 1.23 times (0.41 mg/mL) more potent in scavenging DPPH radicals. Conclusion: The components of soy sauce were found to have potentials of anti-glycation (inhibiting AGE formation) and anti-oxidation (scavenging DPPH radical). The melanoidin efficacy in soy sauce varies depending on the glycation time and raw ingredients (i.e., sugars, amino acids), however, suggesting that it may contribute to both anti-glycation and anti-oxidation.

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In the brains of elderly dementia patients, important proteins (i.e., amyloid β [Aβ], tau, and α-synuclein) undergo post-translational modification, polymerization, aggregation, and deposition in tissues. Glycative stress, a non-physiological factor inducing these phenomena, is a state of excess aldehydes, and is induced by hyperglycemia, a high-fat diet, and alcohol consumption. In the lipid-rich brain, concurrently with carbohydrate-derived aldehydes, FA-derived aldehydes generated by the oxidation of FAs modify brain proteins like a double punch. Our previous reports have shown that glycated Aβ can become resistant to microglia phagocytosis and may interfere with clearance. In this study, we created an Aβ phagocytosis evaluation model using microglia-derived BV2 cells and evaluated the effects of mesenchymal stem cell secretome (SCST). SCST contains various growth factors and extracellular vesicles (EVs), and it has been reported that nasal administration improves symptoms in elderly dementia patients. Present results showed that SCST promotes Aβ phagocytosis in a dose-dependent manner. These findings suggest that SCST may activate microglia and contribute to the homeostasis of Aβ clearance. We speculate that it may also be important from the perspective of gliaprotection.

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Objective: As a preliminary study, we focused on the effects of the intake of processed brown rice on pregnant women and their children. In particular, we focused on the weight of the newborns. Method: This study involved participants answering questionnaires twice, once when they applied to participate and once after giving birth. The method for providing processed brown rice, sub-aleurone layer residual wash-free rice (SARFR), during pregnancy was to have participants apply for it themselves, so that they could consume the rice without interruption. Results: Pregnant women showed improvements in early satiety, constipation, edema, sweating, sensitivity to the cold, and sleep quality. The more satisfied participants were with the project, the greater the improvements in their eyes, weight, colds, and headaches. There was a significant increase in the weight of infants at the one-month checkup compared to the average weight from FY2019 to FY2022. Conclusion: The intake of SARFR reduced physical discomfort and skin problems during pregnancy, suggesting an increase in the weight of the newborn. In the future, it will be necessary to conduct a large-scale study to examine the effects of the intake of processed brown rice during pregnancy on the weight of newborns.

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