Toxicogenomics focuses on assessing the safety of compounds using gene expression profiles. Gene expression signatures from large toxicogenomics databases are expected to perform better than small databases in identifying biomarkers for the prediction and evaluation of drug safety based on a compound's toxicological mechanisms in animal target organs. Over the past 10 years, the Japanese Toxicogenomics Project consortium (TGP) has been developing a large-scale toxicogenomics database consisting of data from 170 compounds (mostly drugs) with the aim of improving and enhancing drug safety assessment. Most of the data generated by the project (e.g. gene expression, pathology, lot number) are freely available to the public via Open TG-GATEs (Toxicogenomics Project-Genomics Assisted Toxicity Evaluation System). Here, we provide a comprehensive overview of the database, including both gene expression data and metadata, with a description of experimental conditions and procedures used to generate the database. Open TG-GATEs is available from http://toxico.nibio.go.jp/english/index.html.

Background: It is increasingly recognized that gut microbiota play a pivotal role in the development of atherosclerotic cardiovascular disease. Previously, we have reported that the abundance of genus Bacteroides is lower in patients with coronary artery disease (CAD) than in patients without CAD with coronary risk factors or in healthy volunteers. However, it remains unclear which and how specific gut bacteria contribute to the progression of atherosclerosis. Methods: We recruited patients with CAD patients and controls without CAD with coronary risk factors. We then compared gut microbial composition using 16S ribosomal RNA gene sequencing in fecal samples to detect species with differential abundance between 2 groups. Subsequently, we used atherosclerosis-prone mice to study the mechanisms underlying the relationship between such species and atherosclerosis. Results: Human fecal 16S ribosomal RNA gene sequencing revealed a significantly lower abundance of Bacteroides vulgatus and Bacteroides dorei in patients with CAD. This significant differential abundance was confirmed by quantitative polymerase chain reaction. Gavage with live B. vulgatus and B. dorei attenuated atherosclerotic lesion formation in atherosclerosis-prone mice, markedly ameliorating endotoxemia followed by decreasing gut microbial lipopolysaccharide production, effectively suppressing proinflammatory immune responses. Furthermore, fecal lipopolysaccharide levels in patients with CAD were significantly higher and negatively correlated with the abundance of B. vulgatus and B. dorei . Conclusions: Our translational research findings identify a previously unknown link between specific gut bacteria and atherosclerosis. Treatment with live B. vulgatus and B. dorei may help prevent CAD. Clinical Trial Registration: URL: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000018051 . Unique identifier: UMIN000015703.

Nitric oxide (NO), constitutively produced by endothelial nitric oxide synthase (eNOS), plays a major role in the regulation of blood pressure and vascular tone. We generated transgenic mice overexpressing bovine eNOS in the vascular wall using murine preproendothelin-1 promoter. In transgenic lineages with three to eight transgene copies, bovine eNOS-specific mRNA, protein expression in the particulate fractions, and calcium-dependent NOS activity were confirmed by RNase protection assay, immunoblotting, and L -arginine/citrulline conversion. Immunohistochemical studies revealed that eNOS protein was predominantly localized in the endothelial cells of aorta, heart, and lung. Blood pressure was significantly lower in eNOS-overexpressing mice than in control littermates. In the transgenic aorta, basal NO release (estimated by N -nitro-L -arginine-induced facilitation of the contraction by prostaglandin F 2 ␣ ) and basal cGMP levels (measured by enzyme immunoassay) were significantly increased. In contrast, relaxations of transgenic aorta in response to acetylcholine and sodium nitroprusside were significantly attenuated, and the reduced vascular reactivity was associated with reduced response of cGMP elevation to these agents as compared with control aortas.

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Nitric oxide (NO) derived from endothelial NO synthase (eNOS) is regarded as a protective factor against atherosclerosis. Therefore, augmentation of eNOS expression or NO production by pharmacological intervention is postulated to inhibit atherosclerosis. We crossed eNOS-overexpressing (eNOS-Tg) mice with atherogenic apoE-deficient (apoE-KO) mice to determine whether eNOS overexpression in the endothelium could inhibit the development of atherosclerosis. After 8 weeks on a high-cholesterol diet, the atherosclerotic lesion areas in the aortic sinus were unexpectedly increased by more than twofold in apoE-KO/eNOS-Tg mice compared with apoE-KO mice. Also, aortic tree lesion areas were approximately 50% larger in apoE-KO/eNOS-Tg mice after 12 weeks on a high-cholesterol diet. Expression of eNOS and NO production in aortas from apoE-KO/eNOS-Tg mice were significantly higher than those in apoE-KO mice. However, eNOS dysfunction, demonstrated by lower NO production relative to eNOS expression and enhanced superoxide production in the endothelium, was observed in apoE-KO/eNOS-Tg mice. Supplementation with tetrahydrobiopterin, an NOS cofactor, reduced the atherosclerotic lesion size in apoE-KO/eNOS-Tg mice to the level comparable to apoE-KO mice, possibly through the improvement of eNOS dysfunction. These data demonstrate that chronic overexpression of eNOS does not inhibit, but accelerates, atherosclerosis under hypercholesterolemia and that eNOS dysfunction appears to play important roles in the progression of atherosclerosis in apoE-KO/eNOS-Tg mice.

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Objective-To determine whether the administration of an active form of vitamin D 3 (calcitriol) could prevent atherosclerosis through anti-inflammatory actions. Methods and Results-Recent clinical studies have shown that lack of vitamin D 3 is a risk factor for cardiovascular events.Oral calcitriol administration decreased atherosclerotic lesions, macrophage accumulation, and CD4 ϩ T-cell infiltration at the aortic sinus, when compared with the corresponding observations in control mice. We observed a significant increase in Foxp3 ϩ regulatory T cells and a decrease in CD80 ϩ CD86 ϩ dendritic cells (DCs) in the mesenteric lymph nodes, spleen, and atherosclerotic lesions in oral calcitriol-treated mice in association with increased interleukin 10 and decreased interleukin 12 mRNA expression. CD11cϩ DCs from the calcitriol group showed reduced proliferative activity of T lymphocytes, suggesting the suppression of DC maturation. Neutralization of CD25 in vivo revealed that calcitriol inhibited atherosclerosis mainly in a regulatory T cell-dependent manner but also partly because of a decrease in DC maturation. , is a secosteroid hormone that not only plays a central role in bone and calcium metabolism but also modulates the immune response. Recent epidemiological studies have shown a relationship between low plasma levels of vitamin D 3 and a predisposition to cardiovascular events. [1][2][3] This finding is supported by a meta-analysis showing that oral vitamin D 3 treatment contributes to the improvement of mortality from all causes, in part by decreasing cardiovascular deaths. 4 Transgenic rats constitutively expressing vitamin D-24-hydroxylase, a model of vitamin D 3 deficiency, showed aggravated atherosclerosis under a high-fat and high-cholesterol diet, when compared with control rats. 5 However, there are no reports about the direct effects of an orally administered active form of vitamin D 3 on atherosclerosis. Conclusion-Oral See accompanying article on page 2317It is widely recognized that atherosclerosis is a complex inflammatory disease of the arterial wall, 6,7 in which the T-lymphocyte-mediated pathogenic immune response plays a critical role. Clinical strategies developed to modulate the immune response have been insufficient for preventing atherosclerosis. Cumulative data based on experimental animal models suggest that CD4 ϩ T cells are present within plaques from the initial stages of the disease in mice, and adaptive transfer of these cells is potentially proatherogenic. 8 Accumulating evidence has revealed novel functions of several subsets of regulatory T cells (Tregs), which maintain immunologic tolerance to self-antigens and inhibit atherosclerosis development by suppressing the inflammatory response of effector T cells. 9 -12 These studies have provided new insights into the immunopathogenesis of atherosclerosis and imply that promotion of regulatory immune responses may have therapeutic potential for suppression of atherosclerotic diseases.In addition to Tregs, dendritic cells (DCs) are al...

Background-Accumulating evidence suggests that several subsets of regulatory T cells that actively mediate immunologic tolerance play crucial roles in atherogenesis. Recently, orally administered anti-CD3 monoclonal antibody has been shown as an inducer of novel regulatory T cells expressing latency-associated peptide (LAP) on their surface, which potently prevents systemic autoimmunity. In the present study, we hypothesized that oral anti-CD3 antibody treatment may inhibit atherosclerosis in mice. Methods and Results-Six-week-old apolipoprotein E-deficient mice on a standard diet were orally given anti-CD3 antibody or control immunoglobulin G on 5 consecutive days, and atherosclerosis was assessed at age 16 weeks. Oral administration of anti-CD3 antibody significantly reduced atherosclerotic lesion formation and accumulations of macrophages and CD4 ϩ T cells in the plaques compared with controls. We observed a significant increase in LAP ϩ cells and CD25ϩ Foxp3 ϩ cells in the CD4 ϩ T-cell population in anti-CD3-treated mice, in association with increased production of the antiinflammatory cytokine transforming growth factor-␤ and suppressed T-helper type 1 and type 2 immune responses. Neutralization of transforming growth factor-␤ in vivo abrogated the preventive effect of oral anti-CD3 antibody. Key Words: atherosclerosis Ⅲ immune system Ⅲ inflammation Ⅲ lymphocytes A therosclerosis is an inflammatory condition of the arterial wall involving cells of innate and adaptive immunity. 1,2 It leads to severe clinical events caused by the rupture of plaques and thrombotic occlusion of the artery and is the main cause of acute coronary syndrome and stroke, which account for approximately half of the deaths in Western countries. It is now widely recognized that chronic inflammation via T-cell-mediated pathogenic immune responses plays an important role in atherogenesis. 2 Accumulating evidence suggests that several subsets of regulatory T cells (Tregs), which have been shown to maintain immunologic unresponsiveness to self-antigens, 3 inhibit atherosclerosis development through the downregulation of activated T-cell responses. 4 -6 These studies imply that promotion of an endogenous regulatory immune response has a therapeutic potential to suppress atherosclerotic diseases. Conclusions-Our Clinical Perspective on p 2005Anti-CD3-specific antibodies strongly suppress immune responses by antigenic modulation of the T-cell receptor/CD3 complex. 7 In 1985, parenteral anti-CD3 antibody was available for use in acute transplant rejection in humans. However, its long-term use is limited because of severe side effects such as mitogenicity and antiglobulin responses. 7 The mitogenicity of anti-CD3 antibody with Fc portion is caused by interacting with Fc receptors (FcRs) on monocytes or macrophages. Therefore, humanized Fc-mutated antibodies were designed and demonstrated to be effective in human autoimmune diabetes for a long period, although they still induce low levels of cytokine release because of some degree of T-cell a...