Publications by authors named "Yurika Otoki"

Article Synopsis
  • - The study focuses on using near infrared (NIR) spectroscopy to monitor the oxidation causes in vegetable oil, which is key for quality control.
  • - Researchers quantified triacylglycerol hydroperoxide (TGOOH) isomers linked to different oxidation processes through liquid chromatography-mass spectrometry, achieving high accuracy with partial least square regression.
  • - The findings suggest that this NIR method can swiftly and easily evaluate the quality of various vegetable oils by detecting subtle changes in specific infrared spectral peaks associated with oxidation.
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  • The roasting process of sesame oil changes its internal composition, which affects its stability against oxidation, but this effect varies depending on the type of oxidation (thermal or photo).
  • The study compared different sesame oils (raw, refined, and roasted) and rapeseed oils by exposing them to thermal oxidation at 120℃ and photo-oxidation at 50,000 lx for 5 and 10 hours.
  • The findings indicate that roasted sesame oil is more stable during thermal oxidation due to antioxidant changes, while refined sesame oil is more stable under photo-oxidation, highlighting the significant impact of both roasting and refining processes on sesame oil’s oxidative stability.
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  • * This study involved administering labeled forms of these acids and their hydroperoxides to mice and measuring the expired CO levels to determine catabolic rates, finding that the hydroperoxides were broken down more quickly than their corresponding fatty acids.
  • * The research suggests that during digestion, these hydroperoxides decompose into medium-chain compounds, which are then quickly absorbed by the liver and metabolized, supporting the idea that dietary lipid hydroperoxides do not enter the intestine intact but
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Ever since the proposal of ferroptosis, it has been studied as a nonapoptotic cell death caused by iron ion-dependent phospholipid (PL) peroxidation. We previously showed that treatment of human hepatoma cell line HepG2 with prepared PL hydroperoxide (PLOOH) resulted in ferroptosis. However, in human sebum, the major hydroperoxide is not PLOOH but squalene hydroperoxide (SQOOH), and to our knowledge, it is not established yet whether SQOOH induces ferroptosis in the skin.

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As known for quite a long time now, even saturated fatty acids can be oxidized at high temperatures to produce unique aroma compounds, such as 2-alkanones and lactones. Hydroperoxide positional isomers with a hydroperoxy group at the 2-, 3-, 4-, or 5-position are hypothesized to be responsible for the formation of these aroma components, but this hypothesis has not been verified. For the first time, this study successfully prepared a series of glyceryl trioctanoate hydroperoxide (C8TG;OOH) isomers.

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Background: Circulating phospholipid species have been shown to predict Alzheimer's disease (AD) prognosis but the link between phospholipid disturbances and subcortical small vessel cerebrovascular disease (CeVD) common in AD patients is not known.

Objective: Mass-spectrometry lipidomics was applied to quantify serum diacyl, alkenyl (ether), alkyl, and lyso phospholipid species in individuals with extensive CeVD (n = 29), AD with minimal CeVD (n = 16), and AD with extensive CeVD (n = 14), and compared them to age-matched controls (n = 27). Memory was assessed using the California Verbal Learning Test.

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Estrogen receptors (ERs) were known as estrogen-activated transcription factors and function as major reproduction regulators in vertebrates. The presence of er genes had been reported in Molluscan cephalopods and gastropods. However, they were considered as constitutive activators with unknown biological functions since reporter assays for these ERs did not show a specific response to estrogens.

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Background Cerebral small vessel disease is associated with higher ratios of soluble-epoxide hydrolase derived linoleic acid diols (12,13-dihydroxyoctadecenoic acid [DiHOME] and 9,10-DiHOME) to their parent epoxides (12(13)-epoxyoctadecenoic acid [EpOME] and 9(10)-EpOME); however, the relationship has not yet been examined in stroke. Methods and Results Participants with mild to moderate small vessel stroke or large vessel stroke were selected based on clinical and imaging criteria. Metabolites were quantified by ultra-high-performance liquid chromatography-mass spectrometry.

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Food lipid oxidation provides various volatile compounds involved in food flavor via the decomposition of lipid hydroperoxide (LOOH). This study predicted the pathways which can coherently explain LOOH decomposition focusing on hydroperoxy octadecadienoic acid (HpODE) isomers (9-EZ-HpODE, 9-EE-HpODE, 10-HpODE, 12-HpODE, 13-ZE-HpODE, and 13-EE-HpODE) which are the major LOOH contained in edible oils. Each standard was first prepared and thermally decomposed.

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Background: Unresolved inflammation in multiple sclerosis (MS) is associated with progressive demyelination and symptom worsening. In the brain, both inflammation and resolution pathways are mediated by free lipid mediators (i.e.

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Article Synopsis
  • The study focuses on understanding the oxidation mechanisms of extra virgin olive oil (EVOO), specifically through radical and singlet oxygen oxidation.
  • Researchers used LC-MS/MS to quantitatively analyze triacylglycerol hydroperoxide (TGOOH) isomers in EVOO, including key standards for specific hydroperoxy triacylglycerols.
  • The findings align with existing knowledge about the oxidation of oils and highlight how factors like olive species and extraction methods affect EVOO's quality and stability.
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Plasmalogen localized in the raft of mammalian cell membranes plays a role in the storage of polyunsaturated fatty acid (PUFA), and exists to a higher extent in malignant cells that survive, and even grow in hypoxic conditions. The biosynthesis of plasmalogen in mammalian cells has been reported to depend on aerobic conditions. Using liquid chromatography-tandem mass spectrometry, we found that the intracellular concentration of plasmalogen species containing a PUFA at the sn-2-position did not change for two days from the start of hypoxic culture in human colorectal cancer-derived Caco2 cells.

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  • 2-Propenal (acrolein) is a toxic compound produced when edible oils break down, and previous studies attributed its formation primarily to radical oxidation of fatty acids.
  • This study examines an alternative pathway for acrolein generation through singlet oxygen oxidation, revealing that certain fatty acid hydroperoxide isomers are key contributors to acrolein production.
  • The findings indicate that oils rich in linoleic acid become more acrolein-rich when exposed to light, suggesting that oil storage and processing conditions can be optimized to minimize acrolein exposure.
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  • The study investigates the effects of hypercapnia/ischemia and brain dissection on brain energy metabolites, using rats and Nuclear Magnetic Resonance to measure changes.
  • It finds that postmortem conditions lead to significant reductions in high-energy phosphates and glucose, while levels of β-hydroxybutyrate and lactate increase across different treatment groups.
  • The research reveals that brain dissection and previous hypoxic conditions cause major alterations in various metabolites, indicating extensive metabolic changes occurring after death.
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Alcoholic fatty liver disease (AFLD) is characterized by lipid accumulation and inflammation and can progress to cirrhosis and cancer in the liver. AFLD diagnosis currently relies on histological analysis of liver biopsies. Early detection permits interventions that would prevent progression to cirrhosis or later stages of the disease.

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Dietary ethanolamine plasmalogen (PlsEtn) has been reported to have several health benefits; however, its functional role during colon pathophysiology remains elusive. The present study investigated the anticolitis effect of dietary ethanolamine glycerophospholipids (EtnGpls) with high PlsEtn from ascidian muscle (86.2 mol %) and low PlsEtn from porcine liver (7.

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Article Synopsis
  • Lipid oxidation plays a role in biological processes like oxidative stress and oxylipin production, making understanding lipid hydroperoxides (LOOHs) crucial.
  • Traditional methods for determining hydroperoxyl group positions in LOOHs have limitations in selectivity, prompting this study to explore how different alkali metals affect LOOH fragmentation.
  • The results showed that fragmentation is influenced by the type and position of alkali metals, with methods developed that can analyze a variety of lipid structures, potentially advancing lipid oxidation research.
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A concise synthesis of a plasmenylethanolamine (PlsEtn-[16:0/18:1 n-9]), known as antioxidative phospholipids commonly found in cell membranes, has been achieved from an optically active known diol through 8 steps. The key transformations for the synthesis of PlsEtn-[16:0/18:1 n-9] are (1) regio- and Z-selective vinyl ether formation via the alkylation of a lithioalkoxy allyl intermediate with an alkyl iodide, and (2) a one-pot phosphite esterification-oxidation sequence to construct the ethanolamine phosphonate moiety in the presence of the vinyl ether functionality. The piperidine salt of synthetic PlsEtn-[16:0/18:1 n-9] was desalinated through reversed-phase high-performance liquid chromatography purification.

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Ethanolamine plasmalogen (PlsEtn) is a subtype of ethanolamine glycerophospholipids (EtnGpl). Recently, PlsEtn has attracted increasing research interest due to its beneficial effects in health and disease; however, its functional role in colonic health has not been well established. This study was conducted to determine the mechanism underlying the antiapoptotic effect of PlsEtn in human intestinal tract cells under induced inflammatory stress.

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Alzheimer's disease (AD) is a progressive and incurable brain disorder that has been associated with structural changes in brain phospholipids (PLs), including diacyl species and ether-linked PLs known as plasmalogens. Most studies have characterized total changes in brain PL pools (e.g.

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Article Synopsis
  • * Researchers compared PlsEtn absorption from two sources: intact ethanolamine glycerophospholipids (EtnGpl) versus hydrolyzed EtnGpl, finding that hydrolysis significantly enhanced PlsEtn levels in the plasma.
  • * The findings suggest that pre-hydrolyzing EtnGpl boosts the absorption of PlsEtn, indicating a more effective method for increasing its bioavailability.
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Ethanolamine plasmalogen (PlsEtn), a sub-class of ethanolamine glycerophospholipids (EtnGpl), is a universal phospholipid in mammalian membranes. Several researchers are interested in the relationship between colon carcinogenesis and colon PlsEtn levels. Here, we evaluated the functional role of dietary purified EtnGpl from the ascidian muscle (87.

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A more comprehensive picture of tissue biology can be obtained through the application and integration of multiple omic technologies. However, the common challenge in working with a precious sample is having a sample too small to separately extract analytes of interest for each experiment. Considering the high heterogeneity that can be present in a single tissue sample, extracting all biomolecules from a single and undivided tissue is preferable because it allows direct comparison of results.

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