Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004153 (atherosclerosis)
 77,401 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The atherosclerotic lesion contains large numbers of macrophages and T lymphocytes. This suggests that a cellular immune response may take place in the lesion, and oxidized lipoproteins, heat shock proteins, and micro-organisms have been implied as candidate antigens. However, the effector mechanisms elicited by this response have been largely unclear. We have therefore analyzed endarterectomy specimens by immunohistochemistry and reverse transcription-PCR to detect immune cytokines produced by immunocompetent cells of the advanced human plaque. The pro-inflammatory T cell cytokines, interleukin-2 and interferon-7, were found in a large proportion of plaques (IL-2 in 50% and interferon-gamma in 30% of plaques by immunohistochemistry and mRNA for both cytokines in 70% of plaques by PCR). In contrast, interleukin-4 and interleukin-5 were rarely observed (both cytokines in 10% of plaques by immunohistochemistry, mRNA for interleukin-4 in 10% and for interleukin-5 in 40% by PCR). This demonstrates the presence of a predominantly pro-inflammatory, Th1-type T cell response in atherosclerosis. This conclusion was further supported by the expression of the pro-inflammatory cytokine, interleukin-1 by plaque macrophages and endothelial cells. In addition, the chemokine interleukin-8 and the macrophage differentiation-stimulating cytokine, granulocyte-monocyte colony stimulating factor, were observed in plaque tissues, suggesting that the micro-environment promotes monocyte recruitment and macrophage differentiation. Occasional eosinophils and B cells were, however observed, which is compatible with a microheterogeneity within the lesion. Finally, the anti-inflammatory and fibrogenic cytokines, transforming growth factor-beta1-3 and its carrier protein, latent TGF-beta binding protein, were found in large amounts in all plaques. Together, these results show that a pro-inflammatory, Thl type cellular immune response takes place in the atherosclerotic plaque. The balance between pro-inflammatory and anti-inflammatory cytokines may be decisive for the progression of the lesion.
Atherosclerosis 1999 Jul
PMID:Cytokine expression in advanced human atherosclerotic plaques: dominance of pro-inflammatory (Th1) and macrophage-stimulating cytokines. 1042 93

Linkage between Chlamydia pneumoniae infection and atherosclerosis has been confirmed in several studies, but the precise role of this organism in the disease process is not known. We investigated the relation and reactivity of T lymphocytes of human carotid plaques to C pneumoniae antigens. Tissue specimens were obtained from 17 patients who underwent carotid endarterectomy. Immunohistological staining and/or in situ hybridization revealed the presence of C pneumoniae in 11 (64%) of the 17 of the cases. Inflammatory infiltration seen in the vessel walls consisted primarily of CD45RO+ T-memory lymphocytes (median 80%, range 50% to 90%), whereas CD20+ B cells and monocytes were in minor proportion. In vivo activated T lymphocytes were propagated from the specimens with interleukin-2, and the antigen specificity of the established T-cell lines (TLLs) was analyzed against C pneumoniae elementary body antigen. TLLs were established from all 17 carotid tissues but none from the control specimens of ascending aorta. C pneumoniae was recognized as a specific T-cell-stimulating antigen in 7 (41%) of 17 cases. Further analyses of the C pneumoniae-reactive TLLs showed that chlamydial 60-kDa heat-shock protein induced specific proliferation in 5 (71%) of 7 cases and revealed 2 haplotype (DRB1*1502 and DQB1*06) binding motifs in human 60-kDa heat-shock protein. C pneumoniae was identified as a specific microbial antigen recognized by 41% of TLLs propagated from in vivo activated plaque T cells. Our results suggests that cell-mediated immunity to C pneumoniae plays a role in the atherosclerotic process and that this response may involve autoimmunity.
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PMID:Detection of Chlamydia pneumoniae-reactive T lymphocytes in human atherosclerotic plaques of carotid artery. 1076 74

Well-preserved natural killer cell (NK) activity has been associated with successful aging. The aim of the present study was to perform detailed analyses of NK cell function and to investigate the clinical significance of the NK cell number and function in relationship to health in a large cohort of elderly humans. It was tested if the potential of natural cytotoxicity in the blood (evaluated as an index including cytotoxicity per NK cell and the number of circulating NK cells) was preserved in 174 81-year-old humans versus 91 young controls and if NK cell mediated immunity was associated with age-related inflammatory diseases such as atherosclerosis. Elderly people had decreased cytotoxicity per NK cell in short-term but not in long-term assays. Ca(2+) independent cytotoxicity was unaltered, and NK cells maintained their cytotoxic responses to interleukin-2 and interferon-alpha signals. The decreased cytotoxicity per NK cell was not completely counteracted by increased circulating numbers of NK cells in the blood. Elderly people with severe medical disorders had low numbers of circulating NK cells. Furthermore, elderly people with atherosclerosis had low cytotoxicity per NK cell and a high number of circulating neutrophils.
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PMID:Decreased natural killer cell activity is associated with atherosclerosis in elderly humans. 1173 53

Activation of T lymphocytes and their ensuing elaboration of proinflammatory cytokines, such as interferon (IFN)-gamma, represent a critical step in atherogenesis and arteriosclerosis. IFNgamma pathways also appear integral to the development of transplantation-associated arteriosclerosis (Tx-AA), limiting long-term cardiac allograft survival. Although disruption of these IFNgamma signaling pathways limits atherosclerosis and Tx-AA in animals, little is known about inhibitory regulation of proinflammatory cytokine production in humans. The present study investigated whether activators of peroxisome proliferator-activated receptor (PPAR)alpha and PPARgamma, with their known antiinflammatory effects, might regulate the expression of proinflammatory cytokines in human CD4-positive T cells. Isolated human CD4-positive T cells express PPARalpha and PPARgamma mRNA and protein. Activation of CD4-positive T cells by anti-CD3 monoclonal antibodies significantly increased IFNgamma protein secretion from 0 to 504+/-168 pg/mL, as determined by ELISA. Pretreatment of cells with well-established PPARalpha (WY14643 or fenofibrate) or PPARgamma (BRL49653/rosiglitazone or pioglitazone) activators reduced anti-CD3-induced IFNgamma secretion in a concentration-dependent manner. PPAR activators also inhibited TNFalpha and interleukin-2 protein expression. In addition, PPAR activators markedly reduced cytokine mRNA expression in these cells. Such antiinflammatory actions were also evident in cell-cell interactions with medium conditioned by PPAR activator-treated T cells attenuating human monocyte CD64 expression and human endothelial cell major histocompatibility complex class II induction. Thus, activation of PPARalpha and PPARgamma in human CD4-positive T cells limits the expression of proinflammatory cytokines, such as IFNgamma, yielding potential therapeutic benefits in pathological processes, such as atherosclerosis and Tx-AA.
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PMID:PPAR activators as antiinflammatory mediators in human T lymphocytes: implications for atherosclerosis and transplantation-associated arteriosclerosis. 1193 39

Growing evidence suggests that atherosclerosis is an immune-mediated inflammatory process and that cytokines participate as mediators in this process. Of the cytokines, interleukins, which are released from both immune and nonimmune cells of vascular wall, are found to have multiple effects. Interleukin-2 (IL-2), a cytokine produced by activated T-lymphocytes, has been found to further activate the T cells and may potentially enhance atherogenesis. Apo-E-deficient mice fed with atherogenic diet were injected intraperitoneally twice a week with placebo, IL-2, or anti-IL-2 antibody for a period of 6 weeks. Group 1 (n = 6) was injected with bovine serum albumin (BSA) in phosphate-buffered saline (PBS) and served as controls. Group 2 (n=6) was injected with 2 x 10(4) units of recombinant murine IL-2 (rmIL-2) per dose reconstituted with BSA in PBS. Group 3 (n=6) was injected with 5 microg of anti-IL-2 per dose reconstituted with BSA in PBS. Aortic sections were analyzed and atherosclerotic burden was quantified. Compared to controls, injection of IL-2 increased measures of atherosclerosis such as the average lesion score (10.7 +/-0.5 vs 9.3 +/-1.1, p=0.04) and the lesion size as a fraction of aortic area (0.51 +/-0.03 vs 0.41 +/-0.05, p=0.01). Injection of anti-IL-2 had a profound antiatherogenic effect. It significantly reduced the average number of lesions per cross section (2.6 +/-0.6 vs 4.3 +/-0.6, p=0.03), the average lesion score (4.6 +/-1.9 vs 9.3 +/-1.1, p=0.02), the lesion area/circumference (0.35 +/-0.08 vs 0.62 +/-0.10, p=0.007), and the lesion size/aortic area (0.23 +/-0.07 vs 0.41 +/-0.05, p=0.03). These results indicate that IL-2 is an atherogenic cytokine in apo-E-deficient mice and anti-IL-2 is protective against atherosclerosis. This may have important clinical implications in modifying the atherosclerotic process.
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PMID:Atherogenic effect of interleukin-2 and antiatherogenic effect of interleukin-2 antibody in apo-E-deficient mice. 1515 62

Oxidized low-density lipoprotein (OxLDL) is an inflammatory modulator in the atherosclerotic plaque. We examined the effect of lysophosphatidylcholine (lysoPC), a main phospholipid component of OxLDL, on inflammatory responses in human CD4 T cells. We found that lysoPC dose- and time-dependently increased expression of CXCR4, the chemokine receptor on CD4 T cells. This increase was inhibited by caffeic acid phenethyl ester or SN50, nuclear factor-kappaB inhibitors, and also by suppression of G2A expression, the specific receptor for lysoPC, using antisense oligonucleotide. lysoPC enhanced CD4 T cell chemotaxis in response to stromal cell-derived factor-1 (SDF-1), the exclusive ligand for CXCR4. lysoPC also enhanced SDF-1-stimulated production of inflammatory cytokines interleukin-2 and interferon-gamma by CD4 T cells activated by anti-CD3 immunoglobulin G. In conclusion, this study demonstrates that lysoPC directly modulates inflammatory responses in human CD4 T cells. The data suggest that the presence of lysoPC and SDF-1 in atherosclerotic lesions may trigger inflammatory responses mediated by CD4 T cells, which may play an important role in progression of atherosclerosis.
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PMID:Lysophosphatidylcholine up-regulates CXCR4 chemokine receptor expression in human CD4 T cells. 1517 7

The aim of the study was to assess the effect of two major groups of hypolipemic drugs, HMG-CoA reductase inhibitors (statins) and PPARalpha activators (fibrates), on the secretory function of T-lymphocytes in patients with primary type II dyslipidemia. Sixty-three patients with type IIa dyslipidemia were randomized to fluvastatin (40 mg daily; n = 33) or simvastatin (20mg daily; n = 30), while 68 type IIb dyslipidemic patients were treated with micronized ciprofibrate (100mg daily; n = 34) or micronized fenofibrate (200mg daily; n = 34). Lipid profile and cytokine (interferon-gamma and interleukin-2) release by phytohemagglutinin-stimulated lymphocytes were determined at the beginning of the study and after 30 and 90 days of treatment. Compared to healthy subjects (n = 59), both type IIa and IIb dyslipidemic patients exhibited higher baseline release of interferon-gamma and interleukin-2. Fluvastatin, simvastatin and, to a less extent, ciprofibrate and fenofibrate inhibited the release of both cytokines, but this effect did not correlate with their lipid-lowering potential. Hypolipemic agents also slightly reduced plasma interleukin-2 levels. Our study suggests that the beneficial effect of hypolipemic drugs involves their inhibitory action on the secretory function of T-lymphocytes. This lipid-independent action is stronger for statins than for fibrates and probably results from their "class" effect. The treatment-induced reduction in the release of both cytokines may contribute to the clinical effectiveness of statins and fibrates in the therapy of atherosclerosis and in the management of organ transplant recipients.
Atherosclerosis 2004 Oct
PMID:The effect of statins and fibrates on interferon-gamma and interleukin-2 release in patients with primary type II dyslipidemia. 1538 Apr 56

Uncoupling protein 2 (UCP2) is a member of the mitochondrial transporter superfamily that is expressed in many tissues, including immune cells. UCP2 prevents oxidative stress by reducing reactive oxygen species. Using UCP2-deficient mice, it was shown that UCP2 is involved in the regulation of insulin secretion, in the resistance to infection, and in atherosclerosis. Here, we investigated the role of UCP2 in experimental autoimmune encephalomyelitis, a murine model of multiple sclerosis. Immunized C57BL/6J UCP2-deficient mice showed a slightly delayed onset during experimental autoimmune encephalomyelitis (13.0 +/- 0.6 versus 11.5 +/- 0.8 in wild-type controls) and developed significantly higher disease scores than littermate controls (maximum disease score of 2.9 +/- 0.2 versus 1.7 +/- 0.2, P = 0.001). Higher levels of infiltrating T cells into the spinal cord meninges and parenchyma were observed. The T-cell proliferative response to the specific antigen was increased in UCP2-deficient mice compared with littermate controls, and CD4 cells of UCP2 knockout mice produced significantly higher levels of pro-inflammatory cytokines, eg, tumor necrosis factor-alpha and interleukin-2, resulting from a Th1 response. Mice lacking UCP2 also developed a higher B-cell response. Concomitantly, CD4 and CD8 cells of the UCP2-deficient mice showed increased production of reactive oxygen species. These results suggest a protective function of UCP2 in chronic inflammatory diseases such as multiple sclerosis.
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PMID:Uncoupling protein 2 has protective function during experimental autoimmune encephalomyelitis. 1665 23

Angiotensin II (Ang II) elicits numerous inflammatory-proliferative responses in vascular cells, thereby being involved in atherosclerosis. We have previously shown that pigment epithelium-derived factor (PEDF) blocks the Ang II-induced endothelial cell activation, thus suggesting that PEDF may play a role in atherosclerosis. However, effects of PEDF on T cell activation, another key steps of atherosclerosis, remain to be elucidated. In this study, we examined whether PEDF could inhibit the Ang II-induced MOLT-3 T cell proliferation in vitro and the way that it might achieve this effect. Ang II significantly stimulated DNA synthesis in MOLT-3 T cells, which was inhibited by PEDF, olmesartan, an Ang II type I receptor blocker, an anti-oxidant N-acetylcysteine (NAC), or antibodies directed against IL-2. PEDF or NAC suppressed gene expression of interleukin-2 (IL-2) in Ang II-exposed MOLT-3 T cells. Furthermore, PEDF blocked the Ang II-induced reactive oxygen species (ROS) generation and NADPH oxidase activity in MOLT-3 T cells. These results demonstrate that PEDF inhibits the Ang II-induced T cell proliferation by blocking autocrine production of IL-2 via suppression of NADPH oxidase-mediated ROS generation. Blockade by PEDF of T cell activation may become a novel therapeutic target for atherosclerosis.
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PMID:Pigment epithelium-derived factor (PEDF) blocks angiotensin II-induced T cell proliferation by suppressing autocrine production of interleukin-2. 1694 72

Adipocytokines are a subset of cytokines produced by adipose tissue and are associated with risk of type II diabetes and atherosclerosis. Levels of adipocytokines differ between Black and White Americans, even after adjustment for differences in adiposity, diseases associated with adipocytokines including type 2 diabetes and cardiovascular disease, and general socioeconomic status indicators such as income. We used a series of ancestry informative markers to estimate genetic ancestry in a population-based study of older Black Americans, and examined the association between genetic ancestry and adipocytokines and soluble receptors to help determine which of these may be most amenable to admixture mapping. We typed 35 ancestry informative markers in 1,241 self-reported Black Americans with available DNA from the Health, Aging, and Body Composition (Health ABC) study with available DNA and used a maximum likelihood approach to estimate percent European ancestry. We used linear regression models to determine the association between these adipocytokines and percent ancestry, and staged models to examine whether adiposity or other measures affected the associations of genetic ancestry and adipocytokines. Mean European ancestry was 22.3+/-15.9%. In multivariate adjusted models, the strongest associations observed were between higher European ancestry and interleukin-6 soluble receptor (IL-6 SR), C-reactive protein (CRP), and adiponectin levels, with interleukin-2 soluble receptor (IL-2 SR) and soluble tumor necrosis factor receptor II (TNF-alpha SR II) also showing more modest but significant associations. The association with adiponectin became stronger after adjustment for adiposity. These novel findings suggest that admixture mapping may identify genetic factors influencing the levels of IL-6 SR, CRP, IL-2 SR, and adiponectin.
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PMID:Genetic admixture, adipocytokines, and adiposity in Black Americans: the Health, Aging, and Body Composition study. 1739 Jan 49


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