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Abstract Determining the content of the nutrient choline in foods and obtaining the required amount from the diet are crucial. One way to measure choline in foods is by converting choline esters to free choline via acid hydrolysis, followed by quantifying the total choline, as adopted by the AOAC method (AOAC-Choline); however, certain choline esters are difficult to hydrolyse. Here, we investigated various acid hydrolysis conditions to establish a reliable method for determining the total choline in foods by detecting free choline using highly sensitive and selective mass spectrometry. Hydrolysis in 0.055 mol/L HCl for 8 h in an autoclave (121 °C) was found to be optimal for the hydrolysis of choline esters in various foods. Twenty-four foods, including grains, seed, vegetables, fruits, mushroom, algae, fish, meats, beverage, processed foods, and egg, were measured. The trends in the total choline content were consistent with previous reports; however, the choline content was 10–20% higher than that measured using AOAC-Choline. Therefore, re-evaluation of the total choline content in foods using our constructed method is recommended. This reassessment will allow for a more reliable determination of choline intake for maintaining health.

While it is well established that the KEAP1-NRF2 pathway regulates the main inducible cellular response to oxidative stress, this cytoprotective function of NRF2 could become deleterious to the host if it confers survival onto irreparably damaged cells. In this regard, we have found that in diseased states, NRF2 promotes the transcriptional activation of a specific subset of the senescence-associated secretory phenotype (SASP) gene program, which we have named the NRF2-induced secretory phenotype (NISP). In two models of hepatic disease using Pten::Keap1 and Keap1::Atg7 double knockout mice, we found that the NISP functions in the liver to recruit CCR2 expressing monocytes, which function as immune system effector cells to directly remove the damaged cells. Through activation of this immune surveillance pathway, in non-transformed cells, NRF2 functions as a tumour suppressor to mitigate the long-term survival of damaged cells which otherwise would be detrimental for host survival. This pathway represents the final stage of the oxidative stress response, as it allows cells to be safely removed if the macromolecular damage caused by the original stressor is so extensive that it is beyond the repair capacity of the cell.

Circadian rhythms are endogenous oscillations that regulate physiological and biochemical processes with approximately 24-h rhythms. Circadian rhythmic disorders caused by a high-fat diet (HFD) are associated with metabolic syndrome and obesity. Herein, we assessed whether black ginger (Kaempferia parviflora) modulates disturbances in the circadian rhythm and improves obesity caused by an HFD in C57BL/6 mice. Three study groups were created: normal diet, HFD, and HFD + K. parviflora extract (KPE). HFD-fed mice showed attenuated circadian locomotor activity, weight gain, and increased serum triglyceride and cholesterol levels, whereas HFD mice administered KPE showed improved circadian locomotor activity and reduced body weight and serum triglyceride levels. Moreover, following RNAi knockdown of clock genes in 3T3-L1 adipocytes, KPE was found to enhance clock gene expression and induce lipolysis-related gene expression in adipocytes. Collectively, these results suggest that KPE improves rhythm disturbances in HFD-fed mice and exhibits anti-obesity effects.

Circadian rhythms are endogenous oscillations of approximately 24-h periods and regulate diel changes in physiological biochemical processes. We examined the effects of black ginger (Kaempferia parviflora) on the expression of circadian clock genes and the disruption of circadian rhythms using in vitro and in vivo assays. K. parviflora extract increased the amplitude of circadian rhythms, extended the circadian period, and caused phase delays in NIH3T3 cells. We identified chemical components involved in the circadian clock gene expression using high-resolution electrospray ionization mass spectrometry and nuclear magnetic resonance. 3,5,7,3′,4′-Pentamethoxyflavone, 5,7,4′-trimethoxyflavone, and 5,7-dimethoxyflavone were identified as components that regulated the circadian clock gene expression. In addition, we examined the effects of K. parviflora on behavioral entrainment in mice subjected to experimental jet lag (6-h phase advance), finding that K. parviflora enhanced adaptation to jet lag. These results suggested that polymethoxyflavones in K. parviflora could regulate the circadian clock and reduce circadian disruption.

β-Conglycinin (β-CG), a major soy protein, has been associated with the reduction of body fat and triglycerides in the blood. Quantitation of the α, α, and β subunits in β-CG is desirable to establish the functional properties of β-CG in soybean. Therefore, in this study, we used the Jess System, a capillary electrophoresis-based immunoassay system, for quantifying β-CG in soybean foods. The validity of this method was confirmed using soybeans and processed soy milk. The within-laboratory reproducibility of the total β-CG amount was < 15 %, and its trueness was > 80 %. The β-CG content in the commercially available soybeans, Kori-tofu, soy milk, soy yogurt, Okara powder, and soy meat was determined to be 40.3-148.5, 65.2-97.2, 6.1-7.8, 3.5, 18.0, and 57.5 mg/g, respectively. For the first time in the literature, this method enables the quantitation of individual subunits of β-CG, despite the large variation in the amount of each subunit. [ABSTRACT FROM AUTHOR]

The glycosylation of proteins and lipids is known to be closely related to the mechanisms of various diseases such as influenza, cancer, and muscular dystrophy. Therefore, it has become clear that the analysis of post-translational modifications of proteins, including glycosylation, is important to accurately understand the functions of each protein molecule and the interactions among them. In order to conduct large-scale analyses more efficiently, it is essential to promote the accumulation, sharing, and reuse of experimental and analytical data in accordance with the FAIR (Findability, Accessibility, Interoperability, and Re-usability) data principles. However, a FAIR data repository for storing and sharing glycoconjugate information, including glycopeptides and glycoproteins, in a standardized format did not exist. Therefore, we have developed GlyComb (https://glycomb.glycosmos.org) as a new standardized data repository for glycoconjugate data. Currently, GlyComb can assign a unique identifier to a set of glycosylation information associated with a specific peptide sequence or UniProt ID. By standardizing glycoconjugate data via GlyComb identifiers and coordinating with existing web resources such as GlyTouCan and GlycoPOST, a comprehensive system for data submission and data sharing among researchers can be established. Here we introduce how GlyComb is able to integrate the variety of glycoconjugate data already registered in existing data repositories to obtain a better understanding of the available glycopeptides and glycoproteins, and their glycosylation patterns. We also explain how this system can serve as a foundation for a better understanding of glycan function. [ABSTRACT FROM AUTHOR]

Foreign amylase addition to honey in an effort to disguise diastase activity has become a widespread form of food fraud. However, since there is no report on the investigation in Japan, we investigated foreign amylases in 67 commercial honeys in Japan. First, the α-glucosidase and diastase activities of honeys were measured, which revealed that only α-glucosidase activity was significantly low in several samples. As both enzymes are secreted from honeybee glands, it is unlikely that only one enzyme was inactivated during processing. Therefore, we suspected the presence of foreign amylase. α-Amylase in honey were assigned using protein analysis software based on LC-QTOF-MS. As a result, α-amylases from Aspergillus and Geobacillus were detected in 13 and 6 out of 67 honeys, respectively. To detect foreign amylases easily, we developed a cost-effective method using native PAGE. Conventional native PAGE failed to separate the α-amylase derived from honeybee and Geobacillus. However, when native PAGE was performed using a gel containing 1 % maltodextrin, the α-amylase from honeybee did not migrated in the gel and the α-amylase could be separated from the other two α-amylases. The results from this method were consistent with those of LC-QTOF-MS method, suggesting that the novel native PAGE method can be used to detect foreign amylases. [ABSTRACT FROM AUTHOR]

Activating mutations in KEAP1-NRF2 are frequently found in tumors of the lung, esophagus, and liver, where they are associated with aggressive growth, resistance to cancer therapies, and low overall survival. Despite the fact that NRF2 is a validated driver of tumorigenesis and chemotherapeutic resistance, there are currently no approved drugs which can inhibit its activity. Therefore, there is an urgent clinical need to identify NRF2-selective cancer therapies. To this end, we developed a novel synthetic lethal assay, based on fluorescently labeled isogenic wild-type and Keap1 knockout cell lines, in order to screen for compounds which selectively kill cells in an NRF2-dependent manner. Through this approach, we identified three compounds based on the geldanamycin scaffold which display synthetic lethality with NRF2. Mechanistically, we show that products of NRF2 target genes metabolize the quinone-containing geldanamycin compounds into more potent HSP90 inhibitors, which enhances their cytotoxicity while simultaneously restricting the synthetic lethal effect to cells with aberrant NRF2 activity. As all three of the geldanamycinderived compounds have been used in clinical trials, they represent ideal candidates for drug repositioning to target the currently untreatable NRF2 activity in cancer. [ABSTRACT FROM AUTHOR]