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1.
Dig Dis Sci ; 68(1): 155-163, 2023 01.
Article in English | MEDLINE | ID: mdl-35397697

ABSTRACT

BACKGROUND: Postmenopausal estrogen decline increases the risk of developing nonalcoholic steatohepatitis (NASH), and it might accelerate progression to cirrhosis and hepatocellular carcinoma. AIMS: This study aimed to investigate a novel therapy for postmenopausal women who are diagnosed with NASH. METHODS: Seven-week-old female C57BL/6 J mice were divided into three experimental groups as follows: (1) sham operation (SHAM group), (2) ovariectomy (OVX group), and (3) ovariectomy + 0.02% astaxanthin (OVX + ASTX group). These three groups of mice were fed a choline-deficient high-fat (CDHF) diet for 8 weeks. Blood serum and liver tissues were collected to examine liver injury, histological changes, and hepatic genes associated with NASH. An in vitro study was performed with the hepatic stellate cell line LX-2. RESULTS: The administration of ASTX significantly improved pathological NASH with suppressed steatosis, inflammation, and fibrosis, in comparison with those in the OVX-induced estrogen deficiency group. As a result, liver injury was also attenuated with reduced levels of alanine aminotransferase and aspartate transaminase. In addition, our study found that ASTX supplementation decreased hepatic osteoprotegerin (OPG) in vivo, a possible factor that contributes to NASH development. In vitro, this study further confirmed that ASTX has an inhibitory effect on the secretion of OPG in LX-2 human hepatic stellate cells. CONCLUSIONS: Our findings suggest that ASTX alleviates CDHF-OVX-induced pathohistological NASH with downregulated OPG, possibly via suppression of the transforming growth factor beta pathway. ASTX could has promise for use in postmenopausal women diagnosed with NASH.


Subject(s)
Non-alcoholic Fatty Liver Disease , Female , Humans , Mice , Animals , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/metabolism , Choline , Diet, High-Fat/adverse effects , Down-Regulation , Osteoprotegerin/genetics , Osteoprotegerin/metabolism , Osteoprotegerin/pharmacology , Mice, Inbred C57BL , Liver/pathology , Liver Cirrhosis/pathology , Fibrosis , Estrogens/pharmacology , Diet
2.
Immunity ; 38(6): 1187-97, 2013 Jun 27.
Article in English | MEDLINE | ID: mdl-23791646

ABSTRACT

The small intestine harbors a substantial number of commensal bacteria and is sporadically invaded by pathogens, but the response to these microorganisms is fundamentally different. We identified a discriminatory sensor by using Toll-like receptor 3 (TLR3). Double-stranded RNA (dsRNA) of one major commensal species, lactic acid bacteria (LAB), triggered interferon-ß (IFN-ß) production, which protected mice from experimental colitis. The LAB-induced IFN-ß response was diminished by dsRNA digestion and treatment with endosomal inhibitors. Pathogenic bacteria contained less dsRNA and induced much less IFN-ß than LAB, and dsRNA was not involved in pathogen-induced IFN-ß induction. These results identify TLR3 as a sensor to small intestinal commensal bacteria and suggest that dsRNA in commensal bacteria contributes to anti-inflammatory and protective immune responses.


Subject(s)
Colitis/prevention & control , Enterococcaceae/immunology , Gram-Positive Bacterial Infections/immunology , Interferon-beta/metabolism , Lactobacillus/immunology , Macrophages/immunology , Toll-Like Receptor 3/metabolism , Animals , Cells, Cultured , Colitis/etiology , Colitis/immunology , Colitis/microbiology , Disease Models, Animal , Enterococcaceae/pathogenicity , Female , Gram-Positive Bacterial Infections/complications , Gram-Positive Bacterial Infections/microbiology , Intestines/immunology , Intestines/microbiology , Macrophages/microbiology , Membrane Transport Proteins/genetics , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Mutant Strains , RNA, Double-Stranded/immunology
3.
Small ; 13(38)2017 10.
Article in English | MEDLINE | ID: mdl-28834273

ABSTRACT

Appropriate adjuvant aiding in generating robust anticancer immunity is crucial for cancer immunotherapy. Herein, hollow ZnO (HZnO) nanospheres are synthesized by a facile method using carbon nanospheres as the template. The HZnO nanospheres significantly promote the cellular uptake of a model antigen, and cytokine secretion by antigen-presenting cells in vitro. HZnO loaded with ovalbumin and polyinosinic-polycytidylic acid (poly(I:C)) inhibits cancer growth and metastasis to inguinal lymph node in a cancer cell challenge model. Moreover, HZnO loaded with autologous cancer antigens inhibits cancer cell growth in a cancer cell re-challenge model. HZnO nanospheres significantly improve the CD4+ and/or CD8+ T cell population in splenocytes of mice in both cancer cell challenge model and re-challenge model. The HZnO nanospheres can be used for cancer immunotherapy as adjuvant.


Subject(s)
Antineoplastic Agents/pharmacology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Immunity , Nanospheres/chemistry , Zinc Oxide/chemistry , Animals , CD4-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/drug effects , Female , Immunity/drug effects , Mice, Inbred C57BL , Nanospheres/ultrastructure , Poly I-C/pharmacology
4.
Small ; 12(26): 3510-5, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27191183

ABSTRACT

Hollow and non-hollow mesoporous silica nanospheres are synthesized and used for cancer vaccine adjuvants. The hollow structure of mesoporous silica nanospheres significantly promote cellular uptake of a model cancer antigen by macrophage-like cells in vitro, improve anti-cancer immunity, CD4(+) and CD8(+) T cell populations in splenocytes of mice in vivo.


Subject(s)
Adjuvants, Immunologic/chemistry , Nanospheres/chemistry , Silicon Dioxide/chemistry , Adjuvants, Immunologic/adverse effects , Animals , Cancer Vaccines/administration & dosage , Cancer Vaccines/chemistry , Cell Survival/drug effects , Mice , Microscopy, Electrochemical, Scanning , Microscopy, Electron, Transmission , NIH 3T3 Cells , Nanospheres/adverse effects , Nanospheres/ultrastructure , Porosity
5.
Angew Chem Int Ed Engl ; 55(5): 1899-903, 2016 Jan 26.
Article in English | MEDLINE | ID: mdl-26404897

ABSTRACT

The use of appropriate adjuvants that support the generation of robust and long-lasting antitumor immune responses is crucial for tumor immunotherapy owing to the immunosuppressive environment of the growing tumor. However, the most commonly used adjuvant, aluminum hydroxide, is ineffective for generating such immune responses and therefore not suitable for cancer immunotherapy. It is now shown that plain hollow mesoporous silica nanospheres markedly improve the antitumor immunity, the Th1 and Th2 immunity, and the CD4(+) and CD8(+) effector memory T cell population in bone marrow in vivo and may thus be used as immunoadjuvants to treat cancer in humans.


Subject(s)
Antineoplastic Agents/pharmacology , Nanospheres , Neoplasms/therapy , Silicon Dioxide/chemistry , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Humans , Immunotherapy , Neoplasms/immunology
6.
PLoS Pathog ; 8(5): e1002714, 2012.
Article in English | MEDLINE | ID: mdl-22693446

ABSTRACT

Specific intestinal microbiota has been shown to induce Foxp3(+) regulatory T cell development. However, it remains unclear how development of another regulatory T cell subset, Tr1 cells, is regulated in the intestine. Here, we analyzed the role of two probiotic strains of intestinal bacteria, Lactobacillus casei and Bifidobacterium breve in T cell development in the intestine. B. breve, but not L. casei, induced development of IL-10-producing Tr1 cells that express cMaf, IL-21, and Ahr in the large intestine. Intestinal CD103(+) dendritic cells (DCs) mediated B. breve-induced development of IL-10-producing T cells. CD103(+) DCs from Il10(-/-), Tlr2(-/-), and Myd88(-/-) mice showed defective B. breve-induced Tr1 cell development. B. breve-treated CD103(+) DCs failed to induce IL-10 production from co-cultured Il27ra(-/-) T cells. B. breve treatment of Tlr2(-/-) mice did not increase IL-10-producing T cells in the colonic lamina propria. Thus, B. breve activates intestinal CD103(+) DCs to produce IL-10 and IL-27 via the TLR2/MyD88 pathway thereby inducing IL-10-producing Tr1 cells in the large intestine. Oral B. breve administration ameliorated colitis in immunocompromised mice given naïve CD4(+) T cells from wild-type mice, but not Il10(-/-) mice. These findings demonstrate that B. breve prevents intestinal inflammation through the induction of intestinal IL-10-producing Tr1 cells.


Subject(s)
Bifidobacterium/immunology , Colon/microbiology , Interleukin-10/metabolism , Lacticaseibacillus casei/immunology , Probiotics/administration & dosage , T-Lymphocytes, Regulatory/cytology , Adoptive Transfer , Animals , Bifidobacteriales Infections/immunology , Bifidobacteriales Infections/microbiology , Bifidobacteriales Infections/therapy , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/transplantation , Cell Differentiation , Coculture Techniques , Colitis/immunology , Colitis/microbiology , Colitis/therapy , Colon/immunology , Dendritic Cells/cytology , Dendritic Cells/immunology , Dendritic Cells/metabolism , Host-Pathogen Interactions , Immunocompromised Host , Interleukin-10/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/metabolism
7.
Cancers (Basel) ; 16(10)2024 May 18.
Article in English | MEDLINE | ID: mdl-38792006

ABSTRACT

Lactococcus lactis subsp. cremoris C60 is a probiotic strain of lactic acid bacteria (LAB) which induces various immune modifications in myeloid lineage cells. These modifications subsequently regulate T cell function, resulting in enhanced immunity both locally and systemically. Here, we report that C60 suppresses tumor growth by enhancing macrophage function via metabolic alterations, thereby increasing adenosine triphosphate (ATP) production in a murine melanoma model. Intragastric (i.g.) administration of C60 significantly reduced tumor volume compared to saline administration in mice. The anti-tumor function of intratumor (IT) macrophage was upregulated in mice administered with C60, as evidenced by an increased inflammatory phenotype (M1) rather than an anti-inflammatory/reparative (M2) phenotype, along with enhanced antigen-presenting ability, resulting in increased tumor antigen-specific CD8+ T cells. Through this functional modification, we identified that C60 establishes a glycolysis-dominant metabolism, rather than fatty acid oxidation (FAO), in IT macrophages, leading to increased intracellular ATP levels. To address the question of why orally supplemented C60 exhibits functions in distal places, we found a possibility that bacterial cell wall components, which could be distributed throughout the body from the gut, may induce stimulatory signals in peripheral macrophages via Toll-like receptors (TLRs) signaling activation. Thus, C60 strengthens macrophage anti-tumor immunity by promoting a predominant metabolic shift towards glycolysis upon TLR-mediated stimulation, thereby increasing substantial energy production.

8.
Front Immunol ; 15: 1335975, 2024.
Article in English | MEDLINE | ID: mdl-38605963

ABSTRACT

Lactic acid bacteria (LAB) possess the ability to argument T cell activity through functional modification of antigen presenting cells (APCs), such as dendritic cells (DCs) and macrophages. Nevertheless, the precise mechanism underlying LAB-induced enhancement of antigen presentation in APCs remains incompletely understood. To address this question, we investigated the detailed mechanism underlying the enhancement of major histocompatibility complex (MHC) class I-restricted antigen presentation in DCs using a probiotic strain known as Lactococcus lactis subsp. Cremoris C60. We found that Heat-killed-C60 (HK-C60) facilitated the processing and presentation of ovalbumin (OVA) peptide antigen OVA257-264 (SIINFEKL) via H-2Kb in bone marrow-derived dendritic cells (BMDCs), leading to increased generation of effector CD8+ T cells both in vitro and in vivo. We also revealed that HK-C60 stimulation augmented the activity of 20S immunoproteasome (20SI) in BMDCs, thereby enhancing the MHC class I-restricted antigen presentation machinery. Furthermore, we assessed the impact of HK-C60 on CD8+ T cell activation in an OVA-expressing B16-F10 murine melanoma model. Oral administration of HK-C60 significantly attenuated tumor growth compared to control treatment. Enhanced Ag processing and presentation machineries in DCs from both Peyer's Patches (PPs) and lymph nodes (LNs) resulted in an increased tumor antigen specific CD8+ T cells. These findings shed new light on the role of LAB in MHC class-I restricted antigen presentation and activation of CD8+ T cells through functional modification of DCs.


Subject(s)
Antigen Presentation , Dendritic Cells , Animals , Mice , Histocompatibility Antigens Class I , CD8-Positive T-Lymphocytes , Antigens , Ovalbumin , Major Histocompatibility Complex
9.
Microorganisms ; 12(4)2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38674685

ABSTRACT

Coccomyxa subellipsoidea KJ (C-KJ) is a green alga with unique immunoregulatory characteristics. Here, we investigated the mechanism underlying the modification of T cell function by C-KJ components. The water-soluble extract of C-KJ was fractionated into protein (P) and sugar (S) fractions acidic (AS), basic (BS), and neutral (NS). These fractions were used for the treatment of peripheral blood mononuclear cells stimulated with toxic shock syndrome toxin-1. Transcriptome analysis revealed that both P and AS enhanced the expression of the genes encoding metallothionein (MT) family proteins, inflammatory factors, and T helper (Th) 17 cytokine and suppressed that of those encoding Th2 cytokines in stimulated T cells. The kinetics of MT1 and MT2A gene expression showed a transient increase in MT1 and maintenance of MT2A mRNA after T cell stimulation in the presence of AS. The kinetics of Th17-related cytokine secretion in the early period were comparable to those of MT2A mRNA. Furthermore, our findings revealed that static, a STAT-3 inhibitor, significantly suppressed MT2A gene expression. These findings suggest that the expression of MTs is involved in the immune regulatory function of C-KJ components, which is partially regulated by Th17 responses, and may help develop innovative immunoregulatory drugs or functional foods.

10.
FEBS Lett ; 598(12): 1478-1490, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38605276

ABSTRACT

The aryl hydrocarbon receptor (AhR) forms a complex with the HSP90-XAP2-p23 molecular chaperone when the cells are exposed to toxic compounds. Recently, 1,4-dihydroxy-2-naphthoic acid (DHNA) was reported to be an AhR ligand. Here, we investigated the components of the molecular chaperone complex when DHNA binds to AhR. Proteins eluted from the 3-Methylcolanthrene-affinity column were AhR-HSP90-XAP2-p23 complex. The AhR-molecular chaperone complex did not contain p23 in the eluents from the DHNA-affinity column. In 3-MC-treated cells, AhR formed a complex with HSP90-XAP2-p23 and nuclear translocation occurred within 30 min, while in DHNA-treated cells, AhR formed a complex with AhR-HSP90-XAP2, and translocation was slow from 60 min. Thus, the AhR activation mechanism may differ when DHNA is the ligand compared to toxic ligands.


Subject(s)
HSP90 Heat-Shock Proteins , Receptors, Aryl Hydrocarbon , Receptors, Aryl Hydrocarbon/metabolism , Ligands , HSP90 Heat-Shock Proteins/metabolism , Humans , Molecular Chaperones/metabolism , Protein Binding , Methylcholanthrene/toxicity , Prostaglandin-E Synthases/metabolism , Prostaglandin-E Synthases/genetics , Animals
11.
Cytokine ; 61(3): 831-41, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23332616

ABSTRACT

IL-2 is a growth factor for activated T cells and is required for maintenance of naturally arising regulatory T cells (nTregs). Mice defective in IL-2/IL-2 receptor signaling pathways have impaired nTregs and suffer from lymphoproliferative disorders, suggesting that IL-2 is present and functional in healthy animals. However, the cellular source of IL-2 is currently unknown. To determine which cells produce IL-2 in healthy animals, we established mice carrying cre gene knock in at the il-2 locus (termed IL-2(cre)). When IL-2(cre) mice were crossed with EGFP reporter mice, EGFP was exclusively expressed by a fraction of CD4 T cells present in both lymphoid and non-lymphoid tissues. Live imaging of IL-2(cre) mice that carry the luciferase reporter showed concentrated localization of luciferase(+) cells in Peyer's patches. These cells were not observed in new born mice but appeared within 3days after birth. Reduction of antigen receptor repertoire by transgene expression reduced their number, indicating that recognition of environmental antigens is necessary for generation of these IL-2 producers in healthy animals. A substantial fraction of EGFP(+) cells also produce IL-10 and IFN-γ, a characteristic profile of type 1 regulatory T cells (Tr1). The data suggest that a group of Tr1 cells have addition roles in immune homeostasis by producing IL-2 along with other cytokines and help maintaining Tregs.


Subject(s)
Health , Interleukin-2/biosynthesis , T-Lymphocytes, Regulatory/cytology , Aging/immunology , Animals , Antigens, Surface/metabolism , CD4-Positive T-Lymphocytes/metabolism , Cell Differentiation , Gene Knock-In Techniques , Green Fluorescent Proteins/metabolism , Homologous Recombination/genetics , Integrases/metabolism , Mice , Mice, Inbred C57BL , Mice, Transgenic , Phenotype , Receptors, Antigen, T-Cell/metabolism , T-Lymphocytes, Regulatory/metabolism , Th1 Cells/cytology , Th2 Cells/cytology
12.
Front Immunol ; 14: 1110001, 2023.
Article in English | MEDLINE | ID: mdl-36798125

ABSTRACT

The female reproductive tract (FRT) and remote/versatile organs in the body share bidirectional communication. In this review, we discuss the framework of the "FRT-organ axes." Each axis, namely, the vagina-gut axis, uterus-gut axis, ovary-gut axis, vagina-bladder axis, vagina-oral axis, uterus-oral axis, vagina-brain axis, uterus-brain axis, and vagina-joint axis, is comprehensively discussed separately. Each axis could be involved in the pathogenesis of not only gynecological diseases but also diseases occurring apart from the FRT. Although the microbiota is clearly a key player in the FRT-organ axes, more quantitative insight into the homeostasis of the microbiota could be provided by host function measurements rather than current microbe-centric approaches. Therefore, investigation of the FRT-organ axes would provide us with a multicentric approach, including immune, neural, endocrine, and metabolic aspects, for understanding the homeostatic mechanism of women's bodies. The framework of the FRT-organ axes could also provide insights into finding new therapeutic approaches to maintain women's health.


Subject(s)
Genitalia, Female , Microbiota , Female , Humans , Genitalia, Female/metabolism , Uterus , Vagina , Ovary
13.
Sci Rep ; 13(1): 192, 2023 01 05.
Article in English | MEDLINE | ID: mdl-36604482

ABSTRACT

The introduction of direct oral anticoagulants (DOACs) has greatly changed the use of anticoagulant therapy in patients with non-valvular atrial fibrillation (Af). Therefore, this study aimed to examine changes in the proportions of oral anticoagulant prescriptions in patients with non-valvular Af aged ≥ 65 years, taking into consideration the risk of cerebral infarction and bleeding. Anticoagulant prescriptions in outpatients aged ≥ 65 years with Af were temporally analyzed using the nationwide claims database in Japan. Trends in anticoagulant prescriptions were examined according to cerebral infarction and bleeding risk. The proportion of anticoagulant prescriptions for 12,076 Af patients increased from 41% in 2011 to 56% in 2015. An increase in DOAC prescriptions was accompanied by an increase in the proportion of anticoagulant prescriptions in each group according to the CHA2DS2-VASc and HAS-BLED scores. The proportion of anticoagulant prescriptions for patients with a high risk of developing cerebral infarction and bleeding showed a marked increase. Trends in anticoagulant prescriptions in Af patient with a CHA2DS2-VASc score ≥ 2 and HAS-BLED scores ≥ 3 showed a marked increase in DOAC prescriptions. The widespread use of DOACs greatly changes the profile the prescription of anticoagulant therapy in patients with Af.


Subject(s)
Atrial Fibrillation , Stroke , Aged , Humans , Atrial Fibrillation/complications , Atrial Fibrillation/drug therapy , Atrial Fibrillation/chemically induced , Stroke/complications , Risk Factors , Anticoagulants/adverse effects , Hemorrhage/drug therapy , Cerebral Infarction/drug therapy , Cerebral Infarction/etiology , Administration, Oral
14.
Nutrients ; 15(6)2023 Mar 19.
Article in English | MEDLINE | ID: mdl-36986203

ABSTRACT

The impact of a high-fat diet (HFD) on intestinal permeability has been well established. When bacteria and their metabolites from the intestinal tract flow into the portal vein, inflammation in the liver is triggered. However, the exact mechanism behind the development of a leaky gut caused by an HFD is unclear. In this study, we investigated the mechanism underlying the leaky gut related to an HFD. C57BL/6J mice were fed an HFD or control diet for 24 weeks, and their small intestine epithelial cells (IECs) were analyzed using deep quantitative proteomics. A significant increase in fat accumulation in the liver and a trend toward increased intestinal permeability were observed in the HFD group compared to the control group. Proteomics analysis of the upper small intestine epithelial cells identified 3684 proteins, of which 1032 were differentially expressed proteins (DEPs). Functional analysis of DEPs showed significant enrichment of proteins related to endocytosis, protein transport, and tight junctions (TJ). Expression of Cldn7 was inversely correlated with intestinal barrier function and strongly correlated with that of Epcam. This study will make important foundational contributions by providing a comprehensive depiction of protein expression in IECs affected by HFD, including an indication that the Epcam/Cldn7 complex plays a role in leaky gut.


Subject(s)
Diet, High-Fat , Tight Junctions , Animals , Mice , Diet, High-Fat/adverse effects , Epithelial Cell Adhesion Molecule/metabolism , Tight Junctions/metabolism , Proteomics , Mice, Inbred C57BL , Intestinal Mucosa/metabolism
15.
Biosci Microbiota Food Health ; 41(3): 130-136, 2022.
Article in English | MEDLINE | ID: mdl-35854694

ABSTRACT

Lactococcus lactis subsp. cremoris C60 is a probiotic strain that induces diverse functional modifications in immune cells. In this report, as a novel effect of C60 on myeloid lineage cells, we show that C60 enhances the immunological function of macrophages that consequently promotes CD4+ T cell activity in an antigen-dependent manner. Heat-killed (HK) C60 induced the production of pro-inflammatory cytokines in thioglycolate-elicited peritoneal macrophages (TPMs) much stronger than Toll-like receptor (TLR) ligand stimulation. The HK-C60 treatment also augmented the expression of antigen-presenting and co-stimulatory molecules, such as major histocompatibility complex (MHC) class II, CD80, and CD86, as well as antigen uptake in TPMs. These HK-C60-mediated functional upregulations in TPMs resulted in the promotion of CD4+ T cell activation in an antigen-dependent manner. Interestingly, the TPMs that originated from the mice fed the HK-C60 diet showed pre-activated characteristics, which was confirmed by the upregulation of cytokine production and antigen presentation-related molecule expression under lipopolysaccharide (LPS) stimulation. Furthermore, the antigen-dependent CD4+ T cell activation was also enhanced by the TPMs. This implied that antigen presentation activity was enhanced in the TPMs that originated from the HK-C60 diet mice. Thus, C60 effectively upregulates the immunological function of macrophages that directly connects to CD4+ T cell-based adaptive immunity.

16.
Biosci Microbiota Food Health ; 41(4): 185-194, 2022.
Article in English | MEDLINE | ID: mdl-36258765

ABSTRACT

Creatine is an organic compound which is utilized in biological activities, especially for adenosine triphosphate (ATP) production in the phosphocreatine system. This is a well-known biochemical reaction that is generally recognized as being mainly driven in specific parts of the body, such as the skeletal muscle and brain. However, our report shows a novel aspect of creatine utilization and ATP synthesis in innate immune cells. Creatine supplementation enhanced immune responses in neutrophils, such as cytokine production, reactive oxygen species (ROS) production, phagocytosis, and NETosis, which were characterized as antibacterial activities. This creatine-induced functional upregulation of neutrophils provided a protective effect in a murine bacterial sepsis model. The mortality rate in mice challenged with Escherichia coli K-12 was decreased by creatine supplementation compared with the control treatment. Corresponding to this decrease in mortality, we found that creatine supplementation decreased blood pro-inflammatory cytokine levels and bacterial colonization in organs. Creatine supplementation significantly increased the cellular ATP level in neutrophils compared with the control treatment. This ATP increase was due to the phosphocreatine system in the creatine-treated neutrophils. In addition, extracellular creatine was used in this ATP synthesis, as inhibition of creatine uptake abolished the increase in ATP in the creatine-treated neutrophils. Thus, creatine is an effective nutrient for modifying the immunological function of neutrophils, which contributes to enhancement of antibacterial immunity.

17.
Front Immunol ; 13: 1001179, 2022.
Article in English | MEDLINE | ID: mdl-36389807

ABSTRACT

Immunological aging is a critical event that causes serious functional impairment in the innate immune system. However, the identification markers and parameters are still poorly understood in immunological aging of myeloid lineage cells. Here, we show that a downregulation of lymphocyte antigen 6 complex locus G6D (Ly-6G) observed in aged mouse neutrophils could serve as a novel marker for the prediction of age-associated functional impairment in the neutrophils. Ly-6G expression was significantly downregulated in the bone marrow (BM) neutrophils of aged mice compared to young mice confirmed by flow cytometry analysis. In vitro experiments using BM-isolated neutrophils showed significant downregulations in their activities, such as phagocytosis, reactive oxygen species (ROS) production, interleukin (IL)-1ß production, neutrophil extracellular trap (NET) formation, and migration as well as bacterial clearance, in the aged mouse neutrophils compared to those of young mice counterparts. Interestingly, the magnitudes of functional parameters were strongly correlated with the Ly-6G expression in the neutrophils. Thus, our results suggest that downregulation of Ly-6G reflects the age-associated functional attenuation of the neutrophils.


Subject(s)
Extracellular Traps , Neutrophils , Mice , Animals , Down-Regulation , Phagocytosis , Histocompatibility Antigens/metabolism , Lymphocytes
18.
J Pharmacol Exp Ther ; 336(3): 743-50, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21098091

ABSTRACT

Transient receptor potential vanilloid 1 (TRPV1) is activated by a variety of stimulations, such as endogenous ligands and low pH, and is believed to play a role in pain transmission. TRPV1 antagonists have been reported to be effective in several animal pain models; however, some compounds induce hyperthermia in animals and humans. We discovered the novel TRPV1 antagonist (R)-N-(1-methyl-2-oxo-1,2,3,4-tetrahydro-7-quinolyl)-2-[(2-methylpyrrolidin-1-yl)methyl]biphenyl-4-carboxamide (AS1928370) in our laboratory. AS1928370 bound to the resiniferatoxin-binding site on TRPV1 and inhibited capsaicin-mediated inward currents with an IC50 value of 32.5 nM. Although AS1928370 inhibited the capsaicin-induced Ca²(+) flux in human and rat TRPV1-expressing cells, the inhibitory effect on proton-induced Ca²(+) flux was extremely small. In addition, AS1928370 showed no inhibitory effects on transient receptor potential vanilloid 4, transient receptor potential ankyrin 1, and transient receptor potential melastatin 8 in concentrations up to 10 µM. AS1928370 improved capsaicin-induced secondary hyperalgesia and mechanical allodynia in an L5/L6 spinal nerve ligation model in rats with respective ED50 values of 0.17 and 0.26 mg/kg p.o. Furthermore, AS1928370 alleviated inflammatory pain in a complete Freund's adjuvant model at 10 mg/kg p.o. AS1928370 had no effect on rectal body temperature up to 10 mg/kg p.o., although a significant hypothermic effect was noted at 30 mg/kg p.o. In addition, AS1928370 showed no significant effect on motor coordination. These results suggest that blockage of the TRPV1 receptor without affecting the proton-mediated TRPV1 activation is a promising approach to treating neuropathic pain because of the potential wide safety margin against hyperthermic effects. As such, compounds such as ASP1928370 may have potential as new analgesic agents for treating neuropathic pain.


Subject(s)
Analgesics/therapeutic use , Benzamides/therapeutic use , Fever , Neuralgia/drug therapy , Pain Measurement/drug effects , Quinolones/therapeutic use , TRPV Cation Channels/antagonists & inhibitors , Analgesics/pharmacology , Animals , Benzamides/chemistry , Benzamides/pharmacology , Capsaicin/pharmacology , Capsaicin/therapeutic use , Fever/chemically induced , HEK293 Cells , Humans , Male , Neuralgia/physiopathology , Pain/drug therapy , Pain/physiopathology , Pain Measurement/methods , Protein Binding/physiology , Quinolones/chemistry , Quinolones/pharmacology , Rats , Rats, Sprague-Dawley , TRPV Cation Channels/physiology
19.
J Immunol ; 183(9): 5608-14, 2009 Nov 01.
Article in English | MEDLINE | ID: mdl-19843945

ABSTRACT

Dendritic cells (DCs) express the immunoregulatory enzyme IDO in response to certain inflammatory stimuli, but it is unclear whether DCs express this enzyme under steady-state conditions in vivo. In this study, we report that the DCs in mesenteric lymph nodes (MLNs) constitutively express functional IDO, which metabolizes tryptophan to kynurenine. In line with a previous report that regulatory T cells (Tregs) can induce IDO in DCs via the CTLA-4/B7 interaction, a substantial proportion of the MLN DCs were located in juxtaposition to Tregs, whereas this tendency was not observed for splenic DCs, which do not express IDO constitutively. When CTLA-4 was selectively deleted in Tregs, the frequency of IDO-expressing DCs in MLNs decreased significantly, confirming CTLA-4's role in IDO expression by MLN DCs. We also found that the MLN DCs produced CCL22, which can attract Tregs via CCR4, and that the phagocytosis of autologous apoptotic cells induced CCL22 expression in CCL22 mRNA-negative DCs. Mice genetically deficient in the receptor for CCL22, CCR4, showed markedly reduced IDO expression in MLN-DCs, supporting the involvement of the CCL22/CCR4 axis in IDO induction. Together with our previous observation that MLN DCs contain much intracytoplasmic cellular debris in vivo, these results indicate that reciprocal interactions between the DCs and Tregs via both B7/CTLA-4 and CCL22/CCR4 lead to IDO induction in MLN DCs, which may be initiated and/or augmented by the phagocytosis of autologous apoptotic cells by intestinal DCs. Such a mechanism may help induce the specific milieu in MLNs that is required for the induction of oral tolerance.


Subject(s)
Antigens, CD/physiology , B7-1 Antigen/physiology , Chemokine CCL22/physiology , Dendritic Cells/enzymology , Dendritic Cells/immunology , Indoleamine-Pyrrole 2,3,-Dioxygenase/genetics , Lymph Nodes/immunology , Receptors, CCR4/physiology , Animals , Antigens, CD/genetics , Antigens, CD/metabolism , B7-1 Antigen/metabolism , CTLA-4 Antigen , Chemokine CCL22/metabolism , Dendritic Cells/metabolism , Dendritic Cells/pathology , Female , Immune Tolerance/genetics , Indoleamine-Pyrrole 2,3,-Dioxygenase/biosynthesis , Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism , Leukopenia/genetics , Leukopenia/immunology , Lymph Nodes/enzymology , Lymph Nodes/metabolism , Lymph Nodes/pathology , Mesentery , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Receptors, CCR4/metabolism
20.
Biosci Biotechnol Biochem ; 75(11): 2178-83, 2011.
Article in English | MEDLINE | ID: mdl-22056443

ABSTRACT

Kjellmaniella crassifolia Miyabe (gagome) is a brown alga. Oral gagome administration (oral gagome) resulted in significant upregulation of IL-10 and IFNγ production by Peyer's patch cells. To assess the adjuvant activity of oral gagome, treated mice were subcutaneously injected with ovalbumin (OVA). The production of cytokines from antigen (Ag)-specific T cells in draining lymph nodes (dLN) and their proliferative response were significantly increased as compared with the control group. These enhancements were associated with increased CD44(hi)CD62L(-) activated/memory T cells in dLN as well as upregulation of Ag-specific IgA level in luminal contents. No upregulation of cytokine production by dLN T cells was observed in dectin-1-deficient mice, suggesting that the effect of gagome on cytokine production is largely dependent on the dectin-1 pathway despite its composite constituents. Our findings indicate that gagome is an effective immunomodulator and a potent adjuvant for both the intestinal and the systemic immune response.


Subject(s)
Adjuvants, Immunologic/administration & dosage , Immunity, Innate/drug effects , Intestines/drug effects , Phaeophyceae/chemistry , Animals , Cell Proliferation , Cells, Cultured , Cytokines/analysis , Female , Immunity, Mucosal/drug effects , Immunoglobulin A/immunology , Interleukin-10/analysis , Intestines/immunology , Lectins, C-Type/metabolism , Mice , Mice, Inbred BALB C , Ovalbumin/immunology , Peyer's Patches/immunology , T-Lymphocytes/immunology
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