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result(s) for
"Hayashi, Shusaku"
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Peptidylarginine deiminase 2 contributes to pathogenesis in trinitrobenzenesulfonic acid-induced colitis through macrophage extracellular trap-independent pathways
by
Kato, Shinichi
,
Hayashi, Shusaku
,
Yasuda, Hiroyuki
in
12-O-Tetradecanoylphorbol-13-acetate
,
631/250/1933
,
692/699/1503/257
2025
Peptidylarginine deiminase 2 (PAD2) is an enzyme that converts arginine to citrulline and is involved in diseases, such as Alzheimer’s diseases, fibrosis and cancer. However, its role in inflammatory bowel disease remains unclear. In this study, we investigated the pathogenic effects of PAD2 on inflammatory bowel disease using a trinitrobenzene sulfonic acid (TNBS)-induced murine colitis model. PAD2-deficient (PAD2KO) mice were generated using CRISPR/Cas9-mediated genomic editing. TNBS injection resulted in body weight loss, extensive colonic erosion, and ulceration in wild-type (WT) mice. However, these responses were significantly attenuated in PAD2KO mice. TNBS-induced increases in myeloperoxidase activity, inflammatory cytokine expression, and macrophage extracellular traps (METs) induction in the colon were significantly reduced in PAD2KO. Furthermore, METs were triggered in peritoneal macrophages obtained from WT mice by A23187 and phorbol myristate acetate, and notably, these responses were not abolished in PAD2KO mice. Moreover, inflammatory cytokine expression and M1 macrophage polarization in peritoneal macrophages obtained from PAD2KO mice was lower than that in peritoneal macrophages from WT mice. Overall, PAD2 contributes to the pathogenesis of TNBS-induced colitis by regulating inflammatory cytokine expression in macrophages through METs-independent pathways. Therefore, PAD2 is a promising target for treating inflammatory bowel disease.
Journal Article
Cholinergic anti-inflammatory pathway ameliorates murine experimental Th2-type colitis by suppressing the migration of plasmacytoid dendritic cells
by
Yamamoto, Takeshi
,
Yoshida, Minako
,
Lee, Jaemin
in
631/250/2504/133/1412
,
631/250/347
,
631/378/1959/1315/1951
2022
Ulcerative colitis (UC) is a chronic inflammatory bowel disease. Several studies have demonstrated that α7 nicotinic acetylcholine receptors (α7nAChRs) exert anti-inflammatory effects on immune cells and nicotine suppress UC onset and relapse. Plasmacytoid dendritic cells (pDCs) reportedly accumulate in the colon of UC patients. Therefore, we investigated the pathophysiological roles of α7nAChRs on pDCs in the pathology of UC using oxazolone (OXZ)-induced Th2-type colitis with BALB/c mice. 2-deoxy-D-glucose, a central vagal stimulant suppressed OXZ colitis, and nicotine also ameliorated OXZ colitis with suppressing Th2 cytokines, which was reversed by α7nAChR antagonist methyllycaconitine. Additionally, α7nAChRs were expressed on pDCs, which were located very close to cholinergic nerve fibers in the colon of OXZ mice. Furthermore, nicotine suppressed CCL21-induced bone marrow-derived pDC migration due to Rac 1 inactivation, which was reversed by methyllycaconitine, a JAK2 inhibitor AG490 or caspase-3 inhibitor AZ-10417808. CCL21 was mainly expressed in the isolated lymphoid follicles (ILFs) of the colon during OXZ colitis. The therapeutic effect of cholinergic pathway on OXZ colitis probably through α7nAChRs on pDCs were attributed to the suppression of pDC migration toward the ILFs. Therefore, the activation of α7nAChRs has innovative therapeutic potential for the treatment of UC.
Journal Article
Changes in vaginal Ureaplasma and Lactobacillus due to antibiotic regimen for premature rupture of membranes
2025
Preterm premature rupture of membranes (PPROM) is associated with preterm delivery and neonatal complications. PPROM is often complicated by intra-amniotic inflammation and/or microbial invasion of the amniotic cavity with Ureaplasma or Mycoplasma . Various prophylactic antibiotic therapies have been proposed to prolong latency between PPROM and delivery, reduce the risk of clinical chorioamnionitis, and improve neonatal complications. However, information on the potential of azithromycin administration to reduce the microbial load of vaginal Ureaplasma and Mycoplasma remains lacking. This prospective cohort study included singleton pregnancies managed with prophylactic antibiotics for PPROM at less than 36 weeks of gestation. All patients received the standard antibiotic regimen for PPROM, which consisted of a single oral azithromycin and intravenous ampicillin every for 2 days followed by 5 days of oral amoxicillin. Vaginal swabs samples were collected when PPROM was confirmed and after the antibiotic regimen administration. The main outcome measures were to investigate the changes in vaginal Ureaplasma, Mycoplasma, and Lactobacillus spp. due to the antibiotic regimen. In addition, the association between the presence and changes in vaginal Ureaplasma and Mycoplasma , pregnancy outcomes, and neonatal complications were examined. Out of 82 eligible PPROM, 51 had positive vaginal Ureaplasma . Thirty-six patients (52.2%) completed the antibiotic regimen. Among those with positive vaginal Ureaplasma who completed the antibiotic regimen, 75% experienced an increase in vaginal Ureaplasma levels. For those who delivered before completing all antibiotic doses, 40% had increased vaginal Ureaplasma levels. Furthermore, the antibiotic regimen resulted in decreased Lactobacillus spp. in almost all cases. It was suggested that azithromycin and ampicillin may not be effective when targeting Ureaplasma or Mycoplasma . Since this study did not search for resistance genes, it cannot be determined that azithromycin resistance in Ureaplasma or Mycoplasma is responsible for the present results. In addition, vaginal Ureaplasma changes were not found to be associated with neonatal sepsis or bronchopulmonary dysplasia. Future studies are needed to revalidate current antibiotic therapy for PPROM.
Journal Article
Improvement of Therapeutic Efficacy of Oral Immunotherapy in Combination with Regulatory T Cell-Inducer Kakkonto in a Murine Food Allergy Model
2017
Oral immunotherapy (OIT) has been considered a promising approach for food allergies (FAs). However, the current OIT strategy is limited in terms of the long-term efficacy and safety. We have previously demonstrated that kakkonto, a traditional Japanese herbal medicine, suppresses the occurrence of allergic symptoms in a murine model of ovalbumin (OVA)-induced FA, which is attributed to the induction of the Foxp3+ CD4+ regulatory T cells. In this study, we established an OIT model using the FA mice with already established allergic symptoms and determined whether kakkonto could improve the efficacy of OIT. The OIT method consisted of initially administrating a very small amount of OVA and slowly increasing the amount. Allergic symptoms decreased in the OIT-treated FA mice. OIT significantly downregulated Th2 immune response-related gene expression in the FA mouse colon, and decreased the level of mouse mast cell protease-1, a marker of mast cell degranulation in the FA mouse plasma. Moreover, the concomitant use of kakkonto significantly enhanced the effectiveness of OIT on the allergic symptoms, and the combination therapy further suppressed the Th2 immune responses and the mast cell degranulation. In addition, OIT significantly increased the population of Foxp3+ CD4+ regulatory T cells in the FA mouse colon, and this population was further increased by OIT in combination with kakkonto. Furthermore, the combined therapy with kakkonto reduced the expression of RA-degrading enzyme CYP26B1 mRNA in the FA mouse colon. These findings indicated that the combination of OIT with kakkonto represents a promising approach for FA treatment.
Journal Article
Indigenous gut microbiota constitutively drive release of ciliary neurotrophic factor from mucosal enteric glia to maintain the homeostasis of enteric neural circuits
by
Yamamoto, Takeshi
,
Gershon, Michael D.
,
Ogata, Hanako
in
Animals
,
Anti-Bacterial Agents - pharmacology
,
Antibiotics
2024
It has recently become clear that the gut microbiota influence intestinal motility, intestinal barrier function, and mucosal immune function; therefore, the gut microbiota are deeply involved in the maintenance of intestinal homeostasis. The effects of the gut microbiota on the enteric nervous system (ENS) in the adult intestine, however, remain poorly understood. In the current study, we investigated the effects of the gut microbiota on the ENS. Male C57BL/6 SPF mice at 12 weeks of age were given a cocktail of four antibiotics (ABX) orally to induce dysbiosis (ABX mice). As early as six hours after ABX administration, the weight of the cecum of ABX mice increased to be significantly greater than that of vehicle-treated animals; moreover, ABX-induced dysbiosis reduced the density of enteric nerve fibers (marked by tubulin-β3 immunoreactivity) in the lamina propria of the proximal colon to approximately 60% that of control. TAK242, a TLR4 antagonist, significantly lowered the nerve fiber density in the lamina propria of the proximal colonic mucosa to approximately 60% that of vehicle-treated SPF mice. We thus developed and tested the hypothesis that mucosal glia expressing TLR4 are activated by enteric bacteria and release neurotrophic factors that contribute to the maintenance of enteric neural circuits. Neurotrophic factors in the mucosa of the SPF mouse proximal colon were examined immunohistochemically. Ciliary neurotrophic factor (CNTF) was abundantly expressed in the lamina propria; most of the CNTF immunoreactivity was observed in mucosal glia (marked by S100β immunoreactivity). Administration of CNTF (subcutaneously, 0.3 mg/kg, 3 doses, 2 hours apart) to ABX mice significantly increased mucosal nerve fiber density in the ABX mouse proximal colon to nearly control levels. The effect of CNTF on enteric mucosal nerve fibers was examined in isolated preparations of proximal colon of ABX mice. As it did in vivo , exposure to CNTF in vitro significantly increased enteric mucosal nerve fiber density in the ABX-treated colon. In conclusion, our evidence suggests that gut microbiota constitutively activate TLR4 signaling in enteric mucosal glia, which secrete CNTF in response. The resulting bacterial-driven glial release of CNTF helps to maintain the integrity of enteric mucosal nerve fibers.
Journal Article
Saireito (TJ-114), a Japanese Traditional Herbal Medicine, Reduces 5-Fluorouracil-Induced Intestinal Mucositis in Mice by Inhibiting Cytokine-Mediated Apoptosis in Intestinal Crypt Cells
by
Utsumi, Daichi
,
Kato, Shinichi
,
Shibata, Junichiro
in
5-Fluorouracil
,
Animals
,
Antimetabolites, Antineoplastic - toxicity
2015
Clinical chemotherapy frequently causes intestinal mucositis as a side effect, which is accompanied by severe diarrhea. We recently showed that the cytokine-mediated apoptotic pathway might be important for the development of intestinal mucositis induced by 5-fluorouracil (5-FU). Saireito, the traditional Japanese herbal (Kampo) medicine, is widely used to treat diarrhea and various inflammatory diseases in Japan. In the present study, we investigated the effect of saireito on 5-FU-induced intestinal mucositis in mice, especially in relation to apoptosis in the intestinal crypt. Male C57BL/6 mice were given 5-FU (50 mg/kg), i.p. once daily for 6 days. Intestinal mucositis was evaluated histochemically. Saireito (100-1000 mg/kg) was administered p.o. twice daily for 6 days. Repeated 5-FU treatment caused severe intestinal mucositis including morphological damage, which was accompanied by body weight loss and diarrhea. Daily administration of saireito reduced the severity of intestinal mucositis in a dose-dependent manner. Body weight loss and diarrhea during 5-FU treatment were also significantly attenuated by saireito administration. The number of apoptotic and caspase-3-activated cells in the intestinal crypt was increased, and was accompanied by up-regulated tumor necrosis factor (TNF)-α and interleukin (IL)-1β mRNA within 24 h of the first 5-FU injection. However, all of these measures were significantly lower after saireito administration. These results suggest that saireito attenuates 5-FU-induced intestinal mucositis. This action may come from the reduction of apoptosis in the intestinal crypt via suppression of the up-regulation of inflammatory cytokines. Therefore, saireito may be clinically useful for the prevention of intestinal mucositis during cancer chemotherapy.
Journal Article
Interleukin-4 Receptor α Subunit Deficiency Alleviates Murine Intestinal Inflammation In Vivo Through the Enhancement of Intestinal Mucosal Barrier Function
2020
Disturbance of epithelial barrier function causes chronic intestinal inflammation such as inflammatory bowel disease. Several studies have reported that Th2 cytokines such as interleukin (IL)-4 and IL-13 play an important role in the regulation of intestinal barrier function. However, the precise role of the IL-4 receptor α subunit (IL-4Rα) in intestinal inflammation remains unclear. Thus, we used an experimental colitis model to investigate the role of IL-4Rα in intestinal inflammation. IL-4Rα-deficient (IL-4Rα-/-) mice and their littermate wild-type (WT) mice were used. Experimental colitis was induced by administration of 3% dextran sulfate sodium (DSS) in the drinking water for seven days. Treatment with DSS caused body weight loss, an increase in the disease activity index and histological abnormalities in WT colitis mice, all of which were significantly attenuated in IL-4Rα-/- colitis mice. Neutrophil infiltration in the colonic mucosa was reduced in IL-4Rα-/- colitis mice compared with WT colitis mice. NADPH oxidase 1 expression and reactive oxygen species production were increased in the colons of IL-4Rα-/- mice. Furthermore, elevated intestinal permeability induced by DSS treatment was suppressed in IL-4Rα-/- colitis mice. These results demonstrate that IL-4Rα-/- mice exhibit reduced susceptibility to DSS-induced colitis. Our present findings suggest that IL-4Rα deficiency enhances intestinal mucosal barrier function through the upregulation of NADPH oxidase 1-dependent reactive oxygen species production, thereby suppressing the development of intestinal inflammation.
Journal Article
Anti-Allergic Role of Cholinergic Neuronal Pathway via α7 Nicotinic ACh Receptors on Mucosal Mast Cells in a Murine Food Allergy Model
by
Yamamoto, Takeshi
,
Sakamoto, Hiroshi
,
Kuramoto, Hirofumi
in
Acetylcholine receptors (nicotinic)
,
Allergies
,
alpha7 Nicotinic Acetylcholine Receptor - physiology
2014
The prevalence of food allergy (FA) has increased in developed countries over the past few decades. However, no effective drug therapies are currently available. Therefore, we investigated cholinergic anti-inflammatory pathway as a regulatory system to ameliorate disrupted mucosal immune homeostasis in the gut based on the pathophysiological elucidation of mucosal mast cells (MMCs) in a murine FA model. BALB/c mice sensitized with ovalbumin received repeated oral ovalbumin for the development of FA. FA mice developed severe allergic diarrhea and exhibited enhanced type 2 helper T (Th2) cell immune responses in both systemic immunity and mucosal immunity, along with MMCs hyperplasia in the colon. MMCs were localized primarily in the strategic position of the mucosal epithelium. Furthermore, the allergic symptoms did not develop in p85α disrupted phosphoinositide-3 kinase-deficient mice that lacked mast cells in the gut. Vagal stimulation by 2-deoxy-D-glucose and drug treatment with nicotinic ACh receptor (nAChR) agonists (nicotine and α7 nAChR agonist GTS-21) alleviated the allergic symptoms in the FA mice. Nicotine treatment suppressed MMCs hyperplasia, enhanced MPO and upregulated mRNA expression of Th1 and Th2 cytokines in the FA mice colon. MMCs, which are negatively regulated by α7 nAChRs, were often located in close proximity to cholinergic CGRP-immunoreactive nerve fibers in the FA mice colon. The present results reveal that the cholinergic neuroimmune interaction via α7 nAChRs on MMCs is largely involved in maintaining intestinal immune homeostasis and can be a target for a new therapy against mucosal immune diseases with homeostatic disturbances such as FA.
Journal Article
KampoDB, database of predicted targets and functional annotations of natural medicines
2018
Natural medicines (i.e., herbal medicines, traditional formulas) are useful for treatment of multifactorial and chronic diseases. Here, we present KampoDB (
http://wakanmoview.inm.u-toyama.ac.jp/kampo/
), a novel platform for the analysis of natural medicines, which provides various useful scientific resources on Japanese traditional formulas Kampo medicines, constituent herbal drugs, constituent compounds, and target proteins of these constituent compounds. Potential target proteins of these constituent compounds were predicted by docking simulations and machine learning methods based on large-scale omics data (e.g., genome, proteome, metabolome, interactome). The current version of KampoDB contains 42 Kampo medicines, 54 crude drugs, 1230 constituent compounds, 460 known target proteins, and 1369 potential target proteins, and has functional annotations for biological pathways and molecular functions. KampoDB is useful for mode-of-action analysis of natural medicines and prediction of new indications for a wide range of diseases.
Journal Article
Therapeutic Benefit in Allergic Dermatitis Derived from the Inhibitory Effect of Byakkokaninjinto on the Migration of Plasmacytoid Dendritic Cells
by
Yamamoto, Takeshi
,
Kadowaki, Makoto
,
Hayashi, Shusaku
in
Adaptive immunity
,
Allergic reaction
,
Allergy
2020
Dendritic cells (DCs) are well known to be essential immunocytes involved in innate and adaptive immunity. DCs are classified as conventional dendritic cells (cDCs) and plasmacytoid dendritic cells (pDCs). Recently, the accumulation of pDCs in inflamed tissues and lymphoid tissues has been considered to be a possible contributing factor in the development of immunological diseases, but little is known about the pathophysiological roles of pDCs in immunological diseases. To date, many studies have demonstrated that many kinds of Kampo formulas can regulate immunological reactions in human immune diseases. Thus, we screened Kampo formulas to identify an agent that inhibits pDC migration. Furthermore, we investigated the therapeutic effects of these formulas on a murine DNFB-induced allergic contact dermatitis model. Bone marrow-derived pDCs (BMpDCs) were derived from the bone marrow cells of BALB/c mice in a culture medium with Flt3 ligand. The effects of Kampo formulas on BMpDC migration were evaluated by assessing the number, velocity, and directionality of BMpDCs chemotaxing toward the more concentrated side of a chemokine (C-C motif) ligand 21 (CCL21) gradient. The Kampo formulas that exerted inhibitory effects on pDC migration were orally administered to DNFB-induced allergic contact dermatitis model mice. Byakkokaninjinto reduced the number of migrated BMpDCs and suppressed the velocity and directionality of BMpDC migration in a chemotaxis assay. Gypsum Fibrosum and Ginseng Radix, which are components of byakkokaninjinto, obviously suppressed the velocity of BMpDC migration. Furthermore, Gypsum Fibrosum significantly suppressed the directionality of BMpDC migration. In DNFB-induced allergic contact dermatitis model mice, byakkokaninjinto markedly abrogated ear swelling in late-phase allergic reactions. In conclusions, byakkokaninjinto, which has an inhibitory effect on pDC migration, was able to prevent the occurrence of allergic contact dermatitis, suggesting that pDCs were involved in the onset of allergic contact dermatitis in the mouse model. Therefore, byakkokaninjinto is anticipated to be a therapeutic agent for disorders related to pDC migration.
Journal Article