Publications by authors named "Nagatake T"

Article Synopsis
  • Bisphenol A (BPA) is a chemical found in many plastic products, and breathing or swallowing it can make allergies worse.
  • When exposed to BPA through eye drops, mice showed increased immune responses and allergic reactions in their bodies.
  • A special protein called DAP12 is important for helping the immune system react correctly to BPA when it touches the eyes.
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Introduction: spp. are a public health concern, yet there is still no effective vaccine or medicine available.

Methods: Here, we developed a -specific antibody and found that it targeted a menaquinol cytochrome reductase complex QcrC.

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Intestinal bacteria metabolize dietary substances to produce bioactive postbiotics, among which some are recognized for their role in promoting host health. We here explored the postbiotic potential of two omega-3 α-linolenic acid-derived metabolites: -10--15-octadecadienoic acid (t10,c15-18:2) and -9--15-octadecadienoic acid (c9,c15-18:2). Dietary intake of lipids rich in omega-3 α-linolenic acid elevated levels of t10,c15-18:2 and c9,c15-18:2 in the serum and feces of mice, an effect dependent on the presence of intestinal bacteria.

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The acetal (-glycoside) bonds of glycans and glycoconjugates are chemically and biologically vulnerable, and therefore -glycosides are of interest as more stable analogs. We hypothesized that, if the -glycoside linkage plays a vital role in glycan function, the biological activities of -glycoside analogs would vary depending on their substituents. Based on this idea, we adopted a "linkage-editing strategy" for the creation of glycan analogs (pseudo-glycans).

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  • The study compares Alcaligenes-derived lipid A (ALA) with a licensed adjuvant, monophosphoryl lipid A (MPLA), to assess their effectiveness in inducing immune responses in mice.
  • While ALA showed slightly better results than MPLA in subcutaneous immunization, it significantly enhanced IgA antibody production during nasal immunization.
  • The mechanism behind ALA's effectiveness is its ability to activate specific dendritic cells in nasal tissue, showcasing its potential as a superior mucosal adjuvant.
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Immune cell activation is essential for cancer rejection; however, the tumor microenvironment leads to deterioration of immune function, which enables cancer cells to survive and proliferate. We previously reported that oral ingestion of Lentinula Edodes Mycelia (L.E.

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Macrophages manifest as various subtypes that play diverse and important roles in immunosurveillance and the maintenance of immunological homeostasis in various tissues. Many studies divide macrophages into two broad groups: M1 macrophages induced by lipopolysaccharide (LPS), and M2 macrophages induced by interleukin 4 (IL-4). However, considering the complex and diverse microenvironment , the concept of M1 and M2 is not enough to explain diversity of macrophages.

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  • * In a mouse model of allergic rhinitis, LBI reduced allergy symptoms by decreasing the production of allergen-specific IgE and affecting germinal center reactions in lymph nodes.
  • * The study suggests that LBI's antiallergic effects are linked to higher serum iodine levels, which induce ferroptosis (a type of cell death) in activated B cells by increasing reactive oxygen species (ROS), potentially leading to reduced allergic reactions.
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Retinol is widely used in topical skincare products to ameliorate skin aging and treat acne and wrinkles; however, retinol and its derivatives occasionally have adverse side effects, including the induction of irritant contact dermatitis. Previously, we reported that mead acid (5,8,11-eicosatrienoic acid), an oleic acid metabolite, ameliorated skin inflammation in dinitrofluorobenzene-induced allergic contact hypersensitivity by inhibiting neutrophil infiltration and leukotriene B production by neutrophils. Here, we showed that mead acid also suppresses retinol-induced irritant contact dermatitis.

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Alcaligenes faecalis was previously identified as an intestinal lymphoid tissue-resident commensal bacteria, and our subsequent studies showed that lipopolysaccharide and its core active element (i.e., lipid A) have a potent adjuvant activity to promote preferentially antigen-specific Th17 response and antibody production.

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Phytoestrogens play pivotal roles in controlling not only the endocrine system but also inflammatory metabolic disorders. However, the effects of dietary phytoestrogens on allergic diseases and underlying mechanisms remain unclear. In this study, we revealed the unique metabolic conversion of phytoestrogen to exert anti-allergic properties, using an ovalbumin-induced allergic rhinitis mouse model.

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  • The study focuses on the gut microbiome's role in diseases, particularly highlighting the Blautia genus, especially B. wexlerae, as beneficial bacteria linked to lower obesity and type 2 diabetes rates in Japanese adults.
  • Administering B. wexlerae to mice led to positive metabolic changes and reduced inflammation, which helped combat obesity and diabetes caused by high-fat diets.
  • The beneficial effects of B. wexlerae stem from its unique amino-acid and carbohydrate metabolism, suggesting potential new ways to prevent and treat metabolic disorders through gut microbiome regulation.
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Dietary ω3 fatty acids have important health benefits and exert their potent bioactivity through conversion to lipid mediators. Here, we demonstrate that microbiota play an essential role in the body's use of dietary lipids for the control of inflammatory diseases. We found that amounts of 10-hydroxy-cis-12-cis-15-octadecadienoic acid (αHYA) and 10-oxo-cis-12-cis-15-octadecadienoic acid (αKetoA) increased in the feces and serum of specific-pathogen-free, but not germ-free, mice when they were maintained on a linseed oil diet, which is high in α-linolenic acid.

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We previously identified spp. as a commensal bacterium that resides in lymphoid tissues, including Peyer's patches. We found that -derived lipopolysaccharide acted as a weak agonist of Toll-like receptor four due to the unique structure of lipid A, which lies in the core of lipopolysaccharide.

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spp., including , is a gram-negative facultative bacterium uniquely residing inside the Peyer's patches. We previously showed that -derived lipopolysaccharides ( LPS) acts as a weak agonist of toll-like receptor 4 to activate dendritic cells and shows adjuvant activity by enhancing IgG and Th17 responses to systemic vaccination.

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Atherosclerosis is a chronic inflammatory disease associated with macrophage aggregate and transformation into foam cells. In this study, we sought to investigate the impact of dietary intake of ω3 fatty acid on the development of atherosclerosis, and demonstrate the mechanism of action by identifying anti-inflammatory lipid metabolite. Mice were exposed to a high-fat diet (HFD) supplemented with either conventional soybean oil or α-linolenic acid-rich linseed oil.

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We analyzed the mechanisms underlying enhanced IgA production in the cells of Peyer's patch cells via membrane vesicles derived from Lactobacillus sakei subsp. sakei NBRC 15893. Depletion of CD11c+ cells from Peyer's patch cells suppressed the enhanced IgA production mediated by membrane vesicles.

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ω3 fatty acids show potent bioactivities via conversion into lipid mediators; therefore, metabolism of dietary lipids is a critical determinant in the properties of ω3 fatty acids in the control of allergic inflammatory diseases. However, metabolic progression of ω3 fatty acids in the skin and their roles in the regulation of skin inflammation remains to be clarified. In this study, we found that 12-hydroxyeicosapentaenoic acid (12-HEPE), which is a 12-lipoxygenase metabolite of eicosapentaenoic acid, was the prominent metabolite accumulated in the skin of mice fed ω3 fatty acid-rich linseed oil.

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Lymphoid-tissue-resident commensal bacteria (LRCs), including , are present in intestinal lymphoid tissue including the Peyer's patches (PPs) of mammals and modulate the host immune system. Although LRCs can colonize within dendritic cells (DCs), the mechanisms through which LRCs persist in DCs and the symbiotic relationships between LRCs and DCs remain to be investigated. Here, we show an intracellular symbiotic system in which the LRC creates a unique energy shift in DCs.

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Article Synopsis
  • T-cell development relies on the thymus environment, where endothelial cells (ECs) play a key role in controlling access to different thymic regions.
  • The thymic cortex has a lower vascular permeability, indicating a blood-thymus barrier (BTB), while the medulla allows access to blood-borne molecules and cells for T-cell tolerance.
  • Claudin-5 (Cld5), a tight junction protein, is critical for maintaining this barrier, as it prevents leakage in the cortex but allows access in the medulla, influencing the movement of mature thymocytes into the bloodstream.
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Homeostatic generation of T cells, which occurs in the thymus, is controlled at least in part by endogenous cytokines and ligands. In addition, nutritional factors are other key regulators for the homeostasis of host immunity, but whether and how nutrition affects the homeostatic generation of thymocytes remains to be established. Here, we showed that vitamin B1 deficiency resulted in a bias toward the maturation of γδ thymocytes accompanied by decreased differentiation into double-positive thymocytes during thymic involution.

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Effective and safe vaccine adjuvants are needed to appropriately augment mucosal vaccine effects. Our previous study demonstrated that lipopolysaccharide (LPS) from Peyer's patch resident stimulated dendritic cells to promote the production of mucosal immunity-enhancing cytokines (e.g.

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spp. are identified as commensal bacteria and have been found to inhabit Peyer's patches in the gut. We previously reported that -derived lipopolysaccharides (LPS) exerted adjuvant activity in systemic vaccination, without excessive inflammation.

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Nasal mucosal tissues are equipped with physical barriers, mucus and cilia, on their surface. The mucus layer captures inhaled materials, and the cilia remove the inhaled materials from the epithelial layer by asymmetrical beating. The effect of nasal physical barriers on the vaccine efficacy remains to be investigated.

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Dietary intake of ω3 polyunsaturated fatty acids such as eicosapentaenoic acid and docosahexaenoic acid is beneficial for health control. We recently identified 17,18-epoxyeicosatetraenoic acid (17,18-EpETE) as a lipid metabolite endogenously generated from eicosapentaenoic acid that exhibits potent anti-allergic and anti-inflammatory properties. However, chemically synthesized 17,18-EpETE is enantiomeric due to its epoxy group-17(),18()-EpETE and 17(),18()-EpETE.

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