51
|
The soy isoflavone genistein blunts nuclear factor kappa-B, MAPKs and TNF-α activation and ameliorates muscle function and morphology in mdx mice. Neuromuscul Disord 2011; 21:579-89. [DOI: 10.1016/j.nmd.2011.04.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Revised: 04/05/2011] [Accepted: 04/27/2011] [Indexed: 11/18/2022]
|
52
|
Alexander BN, Fewell JE. Metyrapone restores the febrile response to Escherichia coli LPS in pregnant rats. Am J Physiol Regul Integr Comp Physiol 2011; 300:R1588-95. [PMID: 21490363 DOI: 10.1152/ajpregu.00785.2010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fever, an important component of the host's defense response to immune challenge, is absent or attenuated in rats near the term of pregnancy. The present experiments were carried out to determine the role of endogenous glucocorticoids in mediating the altered core temperature (Tc) response to exogenous pyrogen (i.e., Escherichia coli LPS). For the experiments, metyrapone-a glucocorticoid synthesis inhibitor-was administered to near-term pregnant rats prior to an EC(100) dose of E. coli LPS. Administration of LPS following vehicle elicited a significant corticosterone response and resulted in a decrease in Tc (i.e., hypothermia). Prior administration of metyrapone, however, which abolished the corticosterone response and altered the pyrogenic/cryogenic cytokine response to LPS, eliminated hypothermia and restored the febrile response. Our results provide evidence that endogenous glucocorticoids play a role in mediating the altered febrile response to immune stimuli observed in rats near the term of pregnancy.
Collapse
Affiliation(s)
- Brent N Alexander
- Alberta Children’s Hospital Research Institute for Child and Maternal Health, Department of Physiology and Pharmacology, University of Calgary, Health Sciences Centre, Canada
| | | |
Collapse
|
53
|
Abstract
CVD (cardiovascular disease) is the leading cause of death for women. Considerable progress has been made in both our understanding of the complexities governing menopausal hormone therapy and our understanding of the cellular and molecular mechanisms underlying hormone and hormone receptor function. Understanding the interplay of atherosclerosis and sex steroid hormones and their cognate receptors at the level of the vessel wall has important ramifications for clinical practice. In the present review, we discuss the epidemiology of CVD in men and women, the clinical impact of sex hormones on CVD, and summarize our current understanding of the pathogenesis of atherosclerosis with a focus on gender differences in CVD, its clinical presentation and course, and pathobiology. The critical animal and human data that pertain to the role of oestrogens, androgens and progestins on the vessel wall is also reviewed, with particular attention to the actions of sex hormones on each of the three key cell types involved in atherogenesis: the endothelium, smooth muscle cells and macrophages. Where relevant, the systemic (metabolic) effects of sex hormones that influence atherogenesis, such as those involving vascular reactivity, inflammation and lipoprotein metabolism, are discussed. In addition, four key current concepts in the field are explored: (i) total hormone exposure time and coronary heart disease risk; (ii) the importance of tissue specificity of sex steroid hormones, critical timing and the stage of atherosclerosis in hormone action; (iii) biomarkers for atherosclerosis with regard to hormone therapy; and (iv) the complex role of sex steroids in inflammation. Future studies in this field will contribute to guiding clinical treatment recommendations for women and help define research priorities.
Collapse
|
54
|
King A, Collins F, Klonisch T, Sallenave JM, Critchley H, Saunders P. An additive interaction between the NFkappaB and estrogen receptor signalling pathways in human endometrial epithelial cells. Hum Reprod 2010; 25:510-8. [PMID: 19955102 PMCID: PMC2806182 DOI: 10.1093/humrep/dep421] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Revised: 11/01/2009] [Accepted: 11/04/2009] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Human embryo implantation is regulated by estradiol (E2), progesterone and locally produced mediators including interleukin-1beta (IL-1beta). Interactions between the estrogen receptor (ER) and NF kappa B (NFkappaB) signalling pathways have been reported in other systems but have not been detailed in human endometrium. METHODS AND RESULTS Real-time PCR showed that mRNA for the p65 and p105 NFkappaB subunits is maximally expressed in endometrium from the putative implantation window. Both subunits are localized in the endometrial epithelium throughout the menstrual cycle. Reporter assays for estrogen response element (ERE) activity were used to examine functional interactions between ER and NFkappaB in telomerase immortalized endometrial epithelial cells (TERT-EEC). E2 and IL-1beta treatment of TERT-EECs enhances ERE activity by a NFkappaB and ER dependent mechanism; this effect could be mediated by ERalpha or ERbeta. E2 and IL-1beta also positively interact to increase endogenous gene expression of prostaglandin E synthase and c-myc. This is a gene-dependent action as there is no additive effect on cyclin D1 or progesterone receptor expression. CONCLUSION In summary, we have established that NFkappaB signalling proteins are expressed in normal endometrium and report that IL-1beta can enhance the actions of E2 in a cell line derived from healthy endometrium. This mechanism may allow IL-1beta, possibly from the developing embryo, to modulate the function of the endometrial epithelium to promote successful implantation, for example by regulating prostaglandin production. Aberrations in the interaction between the ER and NFkappaB signalling pathways may have a negative impact on implantation contributing to pathologies such as early pregnancy loss and infertility.
Collapse
Affiliation(s)
- A.E. King
- Reproductive & Developmental Sciences, University of Edinburgh, Edinburgh, UK
| | - F. Collins
- Medical Research Council Human Reproductive Sciences Unit, Centre for Reproductive Biology, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
| | - T. Klonisch
- Department of Human Anatomy & Cell Science, University of Manitoba, Winnipeg, Canada
| | - J.-M. Sallenave
- Universite Denis Diderot, Paris 7, France
- Unite de Defense Innee et Inflammation, INSERM U874, Batiment Metchnikoff, Institut Pasteur, 25, rue du Dr Roux, 75724 Paris Cedex, France
| | - H.O.D. Critchley
- Reproductive & Developmental Sciences, University of Edinburgh, Edinburgh, UK
| | - P.T.K. Saunders
- Medical Research Council Human Reproductive Sciences Unit, Centre for Reproductive Biology, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
| |
Collapse
|
55
|
Ribas V, Nguyen MTA, Henstridge DC, Nguyen AK, Beaven SW, Watt MJ, Hevener AL. Impaired oxidative metabolism and inflammation are associated with insulin resistance in ERalpha-deficient mice. Am J Physiol Endocrinol Metab 2010; 298:E304-19. [PMID: 19920214 PMCID: PMC2822483 DOI: 10.1152/ajpendo.00504.2009] [Citation(s) in RCA: 222] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Impaired estrogen action is associated with the metabolic syndrome in humans. We sought to determine whether impaired estrogen action in female C57Bl6 mice, produced by whole body Esr1 ablation, could recapitulate aspects of this syndrome, including inflammation, insulin resistance, and obesity. Indeed, we found that global knockout (KO) of the estrogen receptor (ER)alpha leads to reduced oxygen uptake and caloric expenditure compared with wild-type (WT) mice. In addition, fasting insulin, leptin, and PAI-1 levels were markedly elevated, whereas adiponectin levels were reduced in normal chow-fed KO. Furthermore, ERalpha-KO mice exhibited impaired glucose tolerance and marked skeletal muscle insulin resistance that was accompanied by the accumulation of bioactive lipid intermediates, inflammation, and diminished PPARalpha, PPARdelta, and UCP2 transcript levels. Although the relative glucose intolerance and insulin resistance phenotype in KO mice became more severe with high-fat feeding, WT mice were refractory to these dietary-induced effects, and this protection coincided with a marked increase in circulating adiponectin and heat shock protein 72 levels in muscle, liver, and fat. These data indicate that ERalpha is critical for the maintenance of whole body insulin action and protection against tissue inflammation during both normal chow and high-fat feeding.
Collapse
Affiliation(s)
- Vicent Ribas
- David Geffen School of Medicine, Department of Medicine, Division of Endocrinology, Diabetes, and Hypertension, University of California Los Angeles, Los Angeles, California 90095-7073, USA
| | | | | | | | | | | | | |
Collapse
|
56
|
Frasor J, Weaver A, Pradhan M, Dai Y, Miller LD, Lin CY, Stanculescu A. Positive cross-talk between estrogen receptor and NF-kappaB in breast cancer. Cancer Res 2009; 69:8918-25. [PMID: 19920189 DOI: 10.1158/0008-5472.can-09-2608] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Estrogen receptors (ER) and nuclear factor-kappaB (NF-kappaB) are known to play important roles in breast cancer, but these factors are generally thought to repress each other's activity. However, we have recently found that ER and NF-kappaB can also act together in a positive manner to synergistically increase gene transcription. To examine the extent of cross-talk between ER and NF-kappaB, a microarray study was conducted in which MCF-7 breast cancer cells were treated with 17beta-estradiol (E(2)), tumor necrosis factor alpha (TNFalpha), or both. Follow-up studies with an ER antagonist and NF-kappaB inhibitors show that cross-talk between E(2) and TNFalpha is mediated by these two factors. We find that although transrepression between ER and NF-kappaB does occur, positive cross-talk is more prominent with three gene-specific patterns of regulation: (a) TNFalpha enhances E(2) action on approximately 30% of E(2)-upregulated genes; (b) E(2) enhances TNFalpha activity on approximately 15% of TNFalpha-upregulated genes; and (c) E(2) + TNFalpha causes a more than additive upregulation of approximately 60 genes. Consistent with their prosurvival roles, ER and NF-kappaB and their target gene, BIRC3, are involved in protecting breast cancer cells against apoptosis. Furthermore, genes positively regulated by E(2) + TNFalpha are clinically relevant because they are enriched in luminal B breast tumors and their expression profiles can distinguish a cohort of patients with poor outcome following endocrine treatment. Taken together, our findings suggest that positive cross-talk between ER and NF-kappaB is more extensive than anticipated and that these factors may act together to promote survival of breast cancer cells and progression to a more aggressive phenotype.
Collapse
Affiliation(s)
- Jonna Frasor
- Department of Physiology, University of Illinois at Chicago, Chicago, Illinois 60612, USA.
| | | | | | | | | | | | | |
Collapse
|
57
|
Abstract
Macrophages are innate immune cells that play an important role in activation of the immune response and wound healing. Pathogens that require T helper-type 2 (Th2) responses for effective clearance, such as parasitic worms, are strong inducers of alternatively activated or M2 macrophages. However, infections such as bacteria and viruses that require Th1-type responses may induce M2 as a strategy to evade the immune system. M2 are particularly efficient at scavenging self tissues following injury through receptors like the mannose receptor and scavenger receptor-A. Thus, M2 may increase autoimmune disease by presenting self tissue to T cells. M2 may also exacerbate immune complex (IC)-mediated pathology and fibrosis, a hallmark of autoimmune disease in women, due to the release of profibrotic factors such as interleukin-1beta, transforming growth factor-beta, fibronectin and matrix metalloproteinases. We have found that M2 comprise anywhere from 30% to 70% of the infiltrate during acute viral or experimental autoimmune myocarditis, and shifts in M2 populations correlate with increased IC deposition, fibrosis and chronic autoimmune pathology. Thus, women may be at an increased risk of M2-mediated autoimmunity due to estrogen's ability to increase Th2 responses.
Collapse
Affiliation(s)
- Delisa Fairweather
- Department of Environmental Health Sciences, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD 21205, USA.
| | | |
Collapse
|
58
|
Mahmoodzadeh S, Fritschka S, Dworatzek E, Pham TH, Becher E, Kuehne A, Davidson MM, Regitz-Zagrosek V. Nuclear factor-kappaB regulates estrogen receptor-alpha transcription in the human heart. J Biol Chem 2009; 284:24705-14. [PMID: 19584059 DOI: 10.1074/jbc.m109.000463] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Estrogen receptor (ER)-mediated effects have been associated with the modulation of myocardial hypertrophy in animal models and in humans, but the regulation of ER expression in the human heart has not yet been analyzed. In various cell lines and tissues, multiple human estrogen receptor alpha (hERalpha) mRNA isoforms are transcribed from distinct promoters and differ in their 5'-untranslated regions. Using PCR-based strategies, we show that in the human heart the ERalpha mRNA is transcribed from multiple promoters, namely, A, B, C, and F, of which the F-promoter is most frequently used variant. Transient transfection reporter assays in a human cardiac myocyte cell line (AC16) with F-promoter deletion constructs demonstrated a negative regulatory region within this promoter. Site-directed mutagenesis and electrophoretic mobility shift assays indicated that NF-kappaB binds to this region. An inhibition of NF-kappaB activity by parthenolide significantly increased the transcriptional activity of the F-promoter. Increasing NF-kappaB expression by tumor necrosis factor-alpha reduced the expression of ERalpha, indicating that the NF-kappaB pathway inhibits expression of ERalpha in human cardiomyocytes. Finally, 17beta-estradiol induced the transcriptional activity of hERalpha promoters A, B, C, and F. In conclusion, inflammatory stimuli suppress hERalpha expression via activation and subsequent binding of NF-kappaB to the ERalpha F-promoter, and 17beta-estradiol/hERalpha may antagonize the inhibitory effect of NF-kappaB. This suggests interplay between estrogen/estrogen receptors and the pro-hypertrophic and inflammatory responses to NF-kappaB.
Collapse
Affiliation(s)
- Shokoufeh Mahmoodzadeh
- Institute of Gender in Medicine, Charité-Universitaetsmedizin Berlin, Berlin 10115, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
59
|
Ahlbory-Dieker DL, Stride BD, Leder G, Schkoldow J, Trölenberg S, Seidel H, Otto C, Sommer A, Parker MG, Schütz G, Wintermantel TM. DNA binding by estrogen receptor-alpha is essential for the transcriptional response to estrogen in the liver and the uterus. Mol Endocrinol 2009; 23:1544-55. [PMID: 19574448 DOI: 10.1210/me.2009-0045] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The majority of the biological effects of estrogens in the reproductive tract are mediated by estrogen receptor (ER)alpha, which regulates transcription by several mechanisms. Because the tissue-specific effects of some ERalpha ligands may be caused by tissue-specific transcriptional mechanisms of ERalpha, we aimed to identify the contribution of DNA recognition to these mechanisms in two clinically important target organs, namely uterus and liver. We used a genetic mouse model that dissects DNA binding-dependent vs. independent transcriptional regulation elicited by ERalpha. The EAAE mutant harbors amino acid exchanges at four positions of the DNA-binding domain (DBD) of ERalpha. This construct was knocked in the ERalpha gene locus to produce ERalpha((EAAE/EAAE)) mice devoid of a functional ERalpha DBD. The phenotype of the ERalpha((EAAE/EAAE)) mice resembles the general loss-of-function phenotype of alphaER knockout mutant mice with hypoplastic uteri, hemorrhagic ovaries, and impaired mammary gland development. In agreement with this phenotype, the expression pattern of the ERalpha((EAAE/EAAE)) mutant mice in liver obtained by genome-wide gene expression profiling supports the observation of a near-complete loss of estrogen-dependent gene regulation in comparison with the wild type. Further gene expression analyses to validate the results of the microarray data were performed by quantitative RT-PCR. The analyses indicate that both gene activation and repression by estrogen-bound ERalpha rely on an intact DBD in vivo.
Collapse
Affiliation(s)
- Dörthe L Ahlbory-Dieker
- Bayer Schering Pharma AG, Therapeutic Research Group Women's Healthcare, Müllerstrasse 178, 13353 Berlin, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
60
|
Frisancho-Kiss S, Coronado MJ, Frisancho JA, Lau VM, Rose NR, Klein SL, Fairweather D. Gonadectomy of male BALB/c mice increases Tim-3(+) alternatively activated M2 macrophages, Tim-3(+) T cells, Th2 cells and Treg in the heart during acute coxsackievirus-induced myocarditis. Brain Behav Immun 2009; 23:649-57. [PMID: 19126426 PMCID: PMC3148833 DOI: 10.1016/j.bbi.2008.12.002] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Revised: 12/02/2008] [Accepted: 12/03/2008] [Indexed: 10/21/2022] Open
Abstract
The incidence of cardiovascular disease, including inflammatory heart diseases like myocarditis, is increased in men. Similarly, male BALB/c mice infected with coxsackievirus B3 (CVB3) develop more severe acute inflammation in the heart compared to females. To better understand the effect of male sex hormones on cardiac inflammation, we gonadectomized (Gdx) male BALB/c mice and examined acute CVB3-induced myocarditis compared to sham controls. Viral replication in the heart was not significantly altered between Gdx and sham mice. However, gonadectomy significantly reduced testosterone levels and inflammation in the heart. FACS analysis of cell populations isolated from the heart revealed that CD11b(+) cells were significantly reduced in Gdx males. However, a GR1(+)F4/80(+) subset of CD11b(+) cells was significantly increased. Because this subset also expressed the interleukin (IL)-4R and IL-10, we refer to these cells as "alternatively activated" or M2 macrophages. A greater percentage of M2 macrophages in Gdx males expressed the inhibitory receptor Tim-3, while fewer expressed IL-1beta and IL-10. Only M2 macrophages upregulated TLR4 and Tim-3, whereas GR1(-)IL-4R(lo) macrophages did not. Additionally, IL-4(+)CD4(+) Th2 cells, Foxp3(+) regulatory T (Treg) cells and Tim-3(+)CD4(+) T cells were significantly increased in the heart following Gdx. Thus, we report for the first time that the inhibitory receptor Tim-3 is expressed on M2 macrophages. Our findings show that sex hormones and/or other mediators released from the testes inhibit anti-inflammatory populations in the heart including Tim-3(+) M2, Tim-3(+)CD4(+) T cells, Th2 and Treg resulting in more severe acute cardiac inflammation in males following CVB3 infection.
Collapse
Affiliation(s)
- Sylvia Frisancho-Kiss
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health and School of Medicine, Baltimore, MD 21205, USA
| | - Michael J. Coronado
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health and School of Medicine, Baltimore, MD 21205, USA
| | - J. Augusto Frisancho
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health and School of Medicine, Baltimore, MD 21205, USA
| | - Vivian M. Lau
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health and School of Medicine, Baltimore, MD 21205, USA
| | - Noel R. Rose
- Department of Pathology, Johns Hopkins University Bloomberg School of Public Health and School of Medicine, Baltimore, MD 21205, USA,The W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health and School of Medicine, Baltimore, MD 21205, USA
| | - Sabra L. Klein
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health and School of Medicine, Baltimore, MD 21205, USA
| | - DeLisa Fairweather
- Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health and School of Medicine, Baltimore, MD 21205, USA,Department of Pathology, Johns Hopkins University Bloomberg School of Public Health and School of Medicine, Baltimore, MD 21205, USA,Corresponding author. DeLisa Fairweather, PhD, Department of Environmental Health Sciences, Johns Hopkins University, Bloomberg School of Public Health, 615 N. Wolfe Street, Rm. E7628, Baltimore, MD 21205. Ph: 410-955-4712; Fax: 410-955-0116;
| |
Collapse
|
61
|
Naor R, Domankevich V, Shemer S, Sominsky L, Rosenne E, Levi B, Ben-Eliyahu S. Metastatic-promoting effects of LPS: sexual dimorphism and mediation by catecholamines and prostaglandins. Brain Behav Immun 2009; 23:611-21. [PMID: 18951972 PMCID: PMC2723727 DOI: 10.1016/j.bbi.2008.10.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Revised: 09/22/2008] [Accepted: 10/01/2008] [Indexed: 10/21/2022] Open
Abstract
Inflammation is implicated in several medical conditions that are sexually dimorphic, including depression, cardiovascular diseases, autoimmunity, and presumably cancer progression. Here we studied the effects of the proinflammatory agent, LPS, on MADB106 lung tumor retention (LTR), and sought to elucidate underlying mechanisms and sexual dimorphism. F344 male and female rats were administered with LPS (0.001-1mg/kg i.v.) simultaneously with tumor cell inoculation, and treated with a beta-blocker (nadolol, 0.2-0.3mg/kg s.c.), a COX inhibitor (indomethacin, 4mg/kg s.c.) or both drugs. To study the role of NK cells, numbers and cytotoxicity of marginating-pulmonary NK cells were studied, and selective in vivo NK-depletion was employed. Serum levels of corticosterone, IL-6, and TNF-alpha were also assessed. The findings indicated that LPS increased LTR in both sexes, but 10-fold higher doses were needed in females to reach the increase evident in males. Additionally, nadolol and indomethacin reduced the effects of LPS, more so in males. In vivo NK-depletion and ex vivo NK activity studies suggested that LPS affected LTR through both NK-independent and NK-dependent mechanisms, the latter mediated through prostaglandin release in males. Corticosterone, IL-6, and TNF-alpha responses to LPS were sexually dimorphic, but were not associated with LPS or drugs' impacts on LTR. Overall, our findings demonstrate sexual dimorphism in LPS-induced elevated susceptibility to MADB106 experimental metastasis, and in potential humoral underlying mechanisms. Further studies are needed to elucidate additional immunological and non-immunological mediators of these dimorphisms, as well as to assess their involvement in other sexually dimorphic pathologies that are associated with inflammation.
Collapse
|
62
|
Plasma lipid-dependent and -independent effects of dietary soy protein and social status on atherogenesis in premenopausal monkeys: implications for postmenopausal atherosclerosis burden. Menopause 2009; 15:950-7. [PMID: 18427358 DOI: 10.1097/gme.0b013e3181612cef] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE : Atherosclerosis developed during premenopausal years predicts postmenopausal atherosclerosis burden. The objective of this study was to determine the effects of dietary soy protein isolate (SPI) and social status on atherogenesis and arterial gene expression in a premenopausal monkey model. DESIGN : Socially housed premenopausal cynomolgus macaques (n = 84) were fed an atherogenic diet deriving protein from casein/lactalbumin or SPI (containing 1.88 mg isoflavones/g). After 36 months of diet consumption, iliac artery biopsies were assessed for atherosclerosis and expression of mRNA transcripts related to inflammation, macrophage and T-cell content, and estrogen receptors (ERs). RESULTS : SPI reduced plaque size (P < 0.05), total plasma cholesterol, non-high-density lipoprotein cholesterol (HDLc), and the total plasma cholesterol/HDLc ratio (all P < 0.003), while increasing triglycerides (P < 0.006) and HDLc (P < 0.0001). Arterial mRNA for CD68 (P < 0.001), CD3 (P < 0.02), and CD4 (P < 0.001) and inflammatory markers monocyte chemotactic protein-1, intercellular adhesion molecule-1, and interleukin-6 (all P < 0.0001) were also lower in the group receiving SPI. For most outcomes, this effect remained even after adjustments for plaque size and plasma lipid concentrations. Arterial ER-alpha was inversely associated with atherosclerosis (P < 0.02) and increased with SPI (P < 0.001). Subordinate monkeys had lower ER-beta (P < 0.02) and higher interleukin-6 (P < 0.05) transcripts but did not differ from dominant monkeys in extent of atherosclerosis (P > 0.9). CONCLUSIONS : Premenopausal consumption of SPI had plasma lipid-independent beneficial effects on the pathobiological processes involved in atherosclerotic plaque development, thus potentially establishing the basis for reduced postmenopausal complications. Dominant social status provided similar, albeit less extensive, benefits in risk markers.
Collapse
|
63
|
Suppression of interleukin-6-induced C-reactive protein expression by FXR agonists. Biochem Biophys Res Commun 2008; 379:476-9. [PMID: 19118524 DOI: 10.1016/j.bbrc.2008.12.117] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Accepted: 12/17/2008] [Indexed: 12/19/2022]
Abstract
C-reactive protein (CRP), a human acute-phase protein, is a risk factor for future cardiovascular events and exerts direct pro-inflammatory and pro-atherogenic properties. The farnesoid X receptor (FXR), a member of the nuclear hormone receptor superfamily, plays an essential role in the regulation of enterohepatic circulation and lipid homeostasis. In this study, we report that two synthetic FXR agonists, WAY-362450 and GW4064, suppressed interleukin-6-induced CRP expression in human Hep3B hepatoma cells. Knockdown of FXR by short interfering RNA attenuated the inhibitory effect of the FXR agonists and also increased the ability of interleukin-6 to induce CRP production. Furthermore, treatment of wild type C57BL/6 mice with the FXR agonist, WAY-362450, attenuated lipopolysaccharide-induced serum amyloid P component and serum amyloid A3 mRNA levels in the liver, whereas no effect was observed in FXR knockout mice. These data provide new evidence for direct anti-inflammatory properties of FXR.
Collapse
|
64
|
Kalra M, Mayes J, Assefa S, Kaul AK, Kaul R. Role of sex steroid receptors in pathobiology of hepatocellular carcinoma. World J Gastroenterol 2008; 14:5945-61. [PMID: 18932272 PMCID: PMC2760195 DOI: 10.3748/wjg.14.5945] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The striking gender disparity observed in the incidence of hepatocellular carcinoma (HCC) suggests an important role of sex hormones in HCC pathogenesis. Though the studies began as early as in 1980s, the precise role of sex hormones and the significance of their receptors in HCC still remain poorly understood and perhaps contribute to current controversies about the potential use of hormonal therapy in HCC. A comprehensive review of the existing literature revealed several shortcomings associated with the studies on estrogen receptor (ER) and androgen receptor (AR) in normal liver and HCC. These shortcomings include the use of less sensitive receptor ligand binding assays and immunohistochemistry studies for ERα alone until 1996 when ERβ isoform was identified. The animal models of HCC utilized for studies were primarily based on chemical-induced hepatocarcinogenesis with less similarity to virus-induced HCC pathogenesis. However, recent in vitro studies in hepatoma cells provide newer insights for hormonal regulation of key cellular processes including interaction of ER and AR with viral proteins. In light of the above facts, there is an urgent need for a detailed investigation of sex hormones and their receptors in normal liver and HCC. In this review, we systematically present the information currently available on androgens, estrogens and their receptors in normal liver and HCC obtained from in vitro, in vivo experimental models and clinical studies. This information will direct future basic and clinical research to bridge the gap in knowledge to explore the therapeutic potential of hormonal therapy in HCC.
Collapse
|
65
|
Fairweather D, Frisancho-Kiss S, Rose NR. Sex differences in autoimmune disease from a pathological perspective. THE AMERICAN JOURNAL OF PATHOLOGY 2008; 173:600-9. [PMID: 18688037 DOI: 10.2353/ajpath.2008.071008] [Citation(s) in RCA: 394] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Autoimmune diseases affect approximately 8% of the population, 78% of whom are women. The reason for the high prevalence in women is unclear. Women are known to respond to infection, vaccination, and trauma with increased antibody production and a more T helper (Th)2-predominant immune response, whereas a Th1 response and inflammation are usually more severe in men. This review discusses the distribution of autoimmune diseases based on sex and age, showing that autoimmune diseases progress from an acute pathology associated with an inflammatory immune response to a chronic pathology associated with fibrosis in both sexes. Autoimmune diseases that are more prevalent in males usually manifest clinically before age 50 and are characterized by acute inflammation, the appearance of autoantibodies, and a proinflammatory Th1 immune response. In contrast, female-predominant autoimmune diseases that manifest during the acute phase, such as Graves' disease and systemic lupus erythematosus, are diseases with a known antibody-mediated pathology. Autoimmune diseases with an increased incidence in females that appear clinically past age 50 are associated with a chronic, fibrotic Th2-mediated pathology. Th17 responses increase neutrophil inflammation and chronic fibrosis. This distinction between acute and chronic pathology has primarily been overlooked, but greatly impacts our understanding of sex differences in autoimmune disease.
Collapse
Affiliation(s)
- DeLisa Fairweather
- Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, 615 N. Wolfe St., Room E7628, Baltimore, MD 21205, USA.
| | | | | |
Collapse
|
66
|
Booth EA, Lucchesi BR. Estrogen-mediated protection in myocardial ischemia-reperfusion injury. Cardiovasc Toxicol 2008; 8:101-13. [PMID: 18683081 DOI: 10.1007/s12012-008-9022-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2008] [Accepted: 07/18/2008] [Indexed: 12/26/2022]
Abstract
Before menopause, a woman has a relatively low risk for developing cardiovascular disease. After menopause, however, the risk increases nearly twofold and cardiovascular disease remains the number one cause of death among women. Observational trials and studies in animal models of cardiovascular disease suggested that females have reduced injury after myocardial ischemia and reperfusion injury. However, two large clinical trials, the women's health initiative (WHI) and the heart estrogen and progestin replacement study (HERS), found an increase in cardiovascular incidences in women taking hormone replacement therapy. The discrepancy between these data highlights the need for further research on the mechanism of estrogen in the cardiovascular system. Animal studies have demonstrated protective effects by endogenous estrogen (gender differences) and also by the administration of exogenous estrogen. In vivo studies suggest a possible anti-inflammatory mechanism of estrogen. Exogenous estrogen has been shown to have anti-oxidant activities. Pre-treatment with estrogen prior to myocardial ischemia and reperfusion causes a decrease in neutrophil infiltration into the irreversibly injured myocardium, decrease in C-reactive protein expression, and deposition of the membrane attack complex. This review will summarize the protection afforded by estrogen as well as discuss several possible mechanisms of protection for exogenous estrogen administration.
Collapse
Affiliation(s)
- Erin A Booth
- Department of Pharmacology, University of Michigan Medical School, 1301C Medical Science Research Building III, Ann Arbor, MI 48109-5632, USA.
| | | |
Collapse
|
67
|
Stice JP, Knowlton AA. Estrogen, NFkappaB, and the heat shock response. Mol Med 2008; 14:517-27. [PMID: 18431462 PMCID: PMC2323333 DOI: 10.2119/2008-00026.stice] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2008] [Accepted: 04/10/2008] [Indexed: 11/06/2022] Open
Abstract
Estrogen has pleiotropic actions, among which are its anti-apoptotic, anti-inflammatory, and vasodilatory effects. Recently, an interaction between 17beta-estradiol (E2) and the transcription factor nuclear factor kappaB (NFkappaB) has been identified. NFkappaB has a central role in the control of genes involved in inflammation, proliferation, and apoptosis. Prolonged activation of NFkappaB is associated with numerous inflammatory pathological conditions. An important facet of E2 is its ability to modulate activity of NFkappaB via both genomic and nongenomic actions. E2 can activate NFkappaB rapidly via nongenomic pathways, increase cellular resistance to injury, and induce expression of the protective class of proteins, heat shock proteins (HSPs). HSPs can bind to many of the pro-apoptotic and pro-inflammatory targets of NFkappaB and, thus, indirectly inhibit many of its deleterious effects. In addition, HSPs can block NFkappaB activation and binding directly. Similarly, genomic E2 signaling can inhibit NFkappaB, but does so through alternative mechanisms. This review focuses on the molecular mechanisms of cross-talk between E2, NFkappaB, and HSPs, and the biological relevance of this cross-talk.
Collapse
Affiliation(s)
- James P Stice
- Molecular & Cellular Cardiology, University of California, Davis, Davis, California, United States of America
| | - Anne A Knowlton
- Molecular & Cellular Cardiology, University of California, Davis, Davis, California, United States of America
- Cardiovascular Division, Department of Medicine, and the Department of Medical Pharmacology, University of California, Davis, Davis, California, United States of America
- The VA Northern California Health Care System, Mather, California, United States of America
| |
Collapse
|
68
|
The role of estrogen in the formation of experimental abdominal aortic aneurysm. Am J Surg 2008; 197:49-54. [PMID: 18585678 DOI: 10.1016/j.amjsurg.2007.11.022] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2007] [Revised: 10/31/2007] [Accepted: 11/02/2007] [Indexed: 10/21/2022]
Abstract
OBJECTIVE The current study sought to investigate the role of estrogen in the formation of experimental abdominal aortic aneurysm (AAA). METHODS Elastase perfusion of infrarenal AAA animal model was performed in 20 female and 20 male Wistar rats that were randomly divided into an ovariectomized/sham-operated group and an estradiol (E2) experimental/saline control group, respectively. At day 14, E2 was detected, while the mRNA and protein expressions of matrix metalloproteinases 2 and 9 (MMP-2 and -9) in AAA tissue were detected by immunohistochemistry and polymerase chain reaction (PCR). RESULTS The ovariectomized group showed lower estrogen levels and a higher aneurysm dilatation rate and significantly higher MMP-2 and -9 expression compared with the sham-operated group (P < .01), which was in accordance with MMP-2 and -9 mRNA expression. The E2 group showed higher estrogen levels and a lower aneurysm dilatation rate and significantly lower MMP-2 and -9 expression than did the saline control group (P < .01), which was in accordance with MMP-2 and -9 mRNA expression. CONCLUSIONS In the pathogenesis of AAA, estrogen may play an inhibitory role by decreasing expression of MMP-2 and MMP-9 synthesis.
Collapse
|
69
|
Desai MS, Mariscalco MM, Tawil A, Vallejo JG, Smith CW. Atherogenic diet-induced hepatitis is partially dependent on murine TLR4. J Leukoc Biol 2008; 83:1336-44. [PMID: 18334542 DOI: 10.1189/jlb.0607390] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Diets high in cholesterol and cholate such as the Paigen diet have been used to study atherogenesis, lithogenesis, and proinflammatory microvascular changes induced by nutritional hypercholesterolemia. Although these diets lead to chronic hepatic inflammation and fibrosis, the early inflammatory changes have been poorly characterized. TLR4, a known receptor for LPS, is also a receptor for a variety of endogenous ligands and has been implicated in atheroma formation. Here, we specifically examined the early inflammatory response of the liver to the atherogenic (ATH) diet and the possible contribution of TLR4. Animals fed the high-cholesterol/cholate diet for 3 weeks developed a significant, predominantly mononuclear leukocyte infiltration in the liver, hepatic steatosis, elevated hepatic expression of MCP-1, RANTES, and MIP-2, and increased serum levels of liver enzymes. In TLR4-deleted animals, there was a 30% attenuation in the serum alanine transaminase levels and a 50% reduction in the leukocyte infiltration with a fourfold reduction in chemokine expression. In contrast, hepatic steatosis did not differ from wild-type controls. TLR2 deletion had no effect on diet-induced hepatitis but increased the amount of steatosis. We conclude that the early inflammatory liver injury but not hepatic lipid loading induced by the ATH diet in mice is mediated in part by TLR4.
Collapse
Affiliation(s)
- Moreshwar S Desai
- Pediatric Critical Care Medicine, Baylor College of Medicine, Houston, TX 77030-2600, USA
| | | | | | | | | |
Collapse
|
70
|
Nalbandian G, Kovats S. Understanding sex biases in immunity: effects of estrogen on the differentiation and function of antigen-presenting cells. Immunol Res 2008; 31:91-106. [PMID: 15778508 DOI: 10.1385/ir:31:2:091] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The initiation and perpetuation of innate and adaptive immunity is dependent on the ability of professional antigen-presenting cells (APCs) to sense inflammatory stimuli; produce cytokines; and internalize, degrade, and present antigens via surface major histocompatibility complex (MHC) molecules. Dendritic cells (DCs), macrophages, and B lymphocytes express estrogen receptors, indicating that the steroid sex hormone estrogen might directly modulate the function of these cells during immune responses. Sex-specific parameters of immune function have been identified during autoimmunity and the pathogenesis of infectious disease, which show sex biases in their incidence and manifestation; female immunity also varies as estrogen levels change. In this article, we summarize studies that demonstrate effects of estrogen on the differentiation or function of APCs in model in vitro systems, or under circumstances of natural or imposed variation in estrogen levels in vivo.
Collapse
Affiliation(s)
- Greg Nalbandian
- Division of Immunology, Beckman Research Institute, City of Hope National Medical Center, CA 91010, USA
| | | |
Collapse
|
71
|
Abstract
AbstractDietary isoflavones are thought to be cardioprotective due to their structural similarity to oestrogen. Oestrogen is believed to have beneficial effects on endothelial function and may be one of the mechanisms by which premenopausal women are protected against CVD. Decreased NO production and endothelial NO synthase activity, and increased endothelin-1 concentrations, impaired lipoprotein metabolism and increased circulating inflammatory factors result from oestrogen deficiency. Oestrogen acts by binding to oestrogen receptors α and β. Isoflavones have been shown to bind with greater affinity to the latter. Oestrogen replacement therapy is no longer thought to be a safe treatment for prevention of CVD; isoflavones are a possible alternative. Limited evidence from human intervention studies suggests that isoflavones may improve endothelial function, but the available data are not conclusive. Animal studies provide stronger support for a role of isoflavones in the vasculature, with increased vasodilation and endothelial NO synthase activity demonstrated. Cellular mechanisms underlying the effects of isoflavones on endothelial cell function are not yet clear. Possible oestrogen receptor-mediated pathways include modulation of gene transcription, and also non-genomic oestrogen receptor-mediated signalling pathways. Putative non-oestrogenic pathways include inhibition of reactive oxygen species production and up regulation of the protein kinase A pathway (increasing NO bioavailability). Further research is needed to unravel effects of isoflavones on intracellular regulation of the endothelial function. Moreover, there is an urgent need for adequately powered, robustly designed human intervention studies in order to clarify the present equivocal findings.
Collapse
|
72
|
Lobanova YS, Scherbakov AM, Shatskaya VA, Krasil'nikov MA. Mechanism of estrogen-induced apoptosis in breast cancer cells: role of the NF-kappaB signaling pathway. BIOCHEMISTRY (MOSCOW) 2007; 72:320-7. [PMID: 17447886 DOI: 10.1134/s0006297907030108] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The ability of sex steroid hormones to up-regulate the apoptotic signaling proteins is well documented; however, the apoptotic potential of sex hormones is not remarkable and fully compensated by their growth stimulatory action to target cells. In the present study using the long-term cultivation of estrogen-dependent MCF-7 breast cancer cells in steroid-free medium, we have established a cell subline, designed as MCF-7/LS, which was characterized by the resistance to growth stimulatory estradiol action and hypersensitivity to estrogen-induced apoptosis. We have demonstrated that estrogen treatment of the cells does not influence on the level of TNF-R1 or Fas, but dramatically decreases the transcriptional activity of NF-kappaB. Importantly, the MCF-7/LS cells, which are insensitive to growth stimulatory estrogen action, retain the ability to decrease in the NF-kappaB activity in response to estrogen stimulus. Furthermore, the significant increase in the basal (in the absence of ligand) estrogen receptor (ER)-dependent transcriptional activity in the MCF-7/LS cells was revealed and reciprocal transcriptional antagonism between ER and NF-kappaB was demonstrated. Finally, we proved the possible involvement of phosphatidylinositol-3 kinase (PI3K) in the ligand-independent ER activation. In general, the results presented suggest that long-term growth of MCF-7 breast cancer cells in steroid-free medium is accompanied with the increase in the basal ER-dependent transcriptional activity as well as the maintenance of the negative regulatory loop ER-NF-kappaB. The latter may be considered as one of the factors resulting in a disbalance between pro- and anti-apoptotic pathways and enhancement in estrogen apoptotic action in the cells.
Collapse
Affiliation(s)
- Yu S Lobanova
- Institute of Carcinogenesis, Blokhin Cancer Research Center, Russian Academy of Medical Sciences, Moscow, Russia
| | | | | | | |
Collapse
|
73
|
Abstract
There is still an unresolved paradox with respect to the immunomodulating role of estrogens. On one side, we recognize inhibition of bone resorption and suppression of inflammation in several animal models of chronic inflammatory diseases. On the other hand, we realize the immunosupportive role of estrogens in trauma/sepsis and the proinflammatory effects in some chronic autoimmune diseases in humans. This review examines possible causes for this paradox. This review delineates how the effects of estrogens are dependent on criteria such as: 1) the immune stimulus (foreign antigens or autoantigens) and subsequent antigen-specific immune responses (e.g., T cell inhibited by estrogens vs. activation of B cell); 2) the cell types involved during different phases of the disease; 3) the target organ with its specific microenvironment; 4) timing of 17beta-estradiol administration in relation to the disease course (and the reproductive status of a woman); 5) the concentration of estrogens; 6) the variability in expression of estrogen receptor alpha and beta depending on the microenvironment and the cell type; and 7) intracellular metabolism of estrogens leading to important biologically active metabolites with quite different anti- and proinflammatory function. Also mentioned are systemic supersystems such as the hypothalamic-pituitary-adrenal axis, the sensory nervous system, and the sympathetic nervous system and how they are influenced by estrogens. This review reinforces the concept that estrogens have antiinflammatory but also proinflammatory roles depending on above-mentioned criteria. It also explains that a uniform concept as to the action of estrogens cannot be found for all inflammatory diseases due to the enormous variable responses of immune and repair systems.
Collapse
Affiliation(s)
- Rainer H Straub
- Laboratory of Experimental Rheumatology and Neuroendocrino-Immunology, Division of Rheumatology, Department of Internal Medicine I, University Hospital, 93042 Regensburg, Germany.
| |
Collapse
|
74
|
Frisancho-Kiss S, Davis SE, Nyland JF, Frisancho JA, Cihakova D, Barrett MA, Rose NR, Fairweather D. Cutting edge: cross-regulation by TLR4 and T cell Ig mucin-3 determines sex differences in inflammatory heart disease. THE JOURNAL OF IMMUNOLOGY 2007; 178:6710-4. [PMID: 17513715 DOI: 10.4049/jimmunol.178.11.6710] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Recent clinical studies have reinforced the importance of sex-related differences in the pathogenesis of cardiovascular diseases, with an increased incidence and mortality in men. Similar to humans, male BALB/c mice infected with coxsackievirus B3 (CVB3) develop more severe inflammation in the heart even though viral replication is no greater than in females. We show that TLR4 and IFN-gamma levels are significantly elevated and regulatory T cell (Treg) populations significantly reduced in the heart of males following CVB3 infection, whereas females have significantly increased T cell Ig mucin (Tim)-3, IL-4 and Treg. Blocking Tim-3 in males significantly increases inflammation and TLR4 expression while reducing Treg. In contrast, defective TLR4 signaling significantly reduces inflammation while increasing Tim-3 expression. Cross-regulation of TLR4 and Tim-3 occurs during the innate and adaptive immune response. This novel mechanism may help explain why inflammatory heart disease is more severe in males.
Collapse
Affiliation(s)
- Sylvia Frisancho-Kiss
- Department of Environmental Health Sciences, Johns Hopkins University, Bloomberg School of Public Health and School of Medicine, Baltimore, MD 21205, USA
| | | | | | | | | | | | | | | |
Collapse
|
75
|
Walker SE, Adams MR, Franke AA, Register TC. Effects of dietary soy protein on iliac and carotid artery atherosclerosis and gene expression in male monkeys. Atherosclerosis 2007; 196:106-113. [PMID: 17367795 PMCID: PMC2657082 DOI: 10.1016/j.atherosclerosis.2007.02.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2006] [Revised: 01/23/2007] [Accepted: 02/08/2007] [Indexed: 10/23/2022]
Abstract
Male cynomolgus macaques (n=91) consumed an isoflavone (IF)-free, atherogenic control diet containing casein/lactalbumin for 5 months, then were randomized to three groups: control (n=30) continued on the control diet; low IF (n=30) received a mixture of unmodified and IF-depleted soy protein isolate (SPI) (0.94 mg IF/g protein, approximating a human intake of 75 mg/day); high IF (n=31) received unmodified SPI (1.88 mg IF/g protein, approximating a human intake of 150 mg/day) for 31 months. Iliac and carotid artery atherosclerosis, and arterial and hepatic mRNA transcripts related to inflammation and estrogen receptors (ER) were measured. Trend analysis identified a significant inverse relationship between dietary IF content and plaque area in the iliac (p<0.05) but not carotid arteries (p>0.13). No significant effect of diet on inflammatory gene or estrogen receptor expression was observed. Plaque area was positively correlated with the mRNA transcript levels for arterial MCP-1, ICAM-1, and the macrophage marker CD68 (all r>0.25, p<0.03), and negatively correlated with ER alpha and ER beta (all r<-0.23, p<0.03). Coronary artery plaque area appeared to be more closely associated with gene expression patterns of the iliac arteries than the carotid arteries. The data suggests benefits of dietary soy on atherosclerotic plaque development in males may be mediated through inflammation-independent pathways. The negative associations of arterial ER alpha expression with atherosclerosis lend support to a mechanistic role for estrogen receptors in atherosclerosis susceptibility which merits further study.
Collapse
Affiliation(s)
- Sara E Walker
- Comparative Medicine Clinical Research Center (SEW, TCR,MRA), Wake Forest University School of Medicine, Medical Center Boulevard., Winston-Salem, NC 27157-1040, USA
| | - Michael R Adams
- Comparative Medicine Clinical Research Center (SEW, TCR,MRA), Wake Forest University School of Medicine, Medical Center Boulevard., Winston-Salem, NC 27157-1040, USA
| | - Adrian A Franke
- The Cancer Research Center of Hawaii, Honolulu, HI 96813, USA
| | - Thomas C Register
- Comparative Medicine Clinical Research Center (SEW, TCR,MRA), Wake Forest University School of Medicine, Medical Center Boulevard., Winston-Salem, NC 27157-1040, USA.
| |
Collapse
|
76
|
Richette P, Dumontier MF, Tahiri K, Widerak M, Torre A, Benallaoua M, Benallaloua M, Rannou F, Corvol MT, Savouret JF. Oestrogens inhibit interleukin 1beta-mediated nitric oxide synthase expression in articular chondrocytes through nuclear factor-kappa B impairment. Ann Rheum Dis 2006; 66:345-50. [PMID: 17068060 PMCID: PMC1856006 DOI: 10.1136/ard.2006.059550] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
OBJECTIVES To investigate the presence and functionality of oestrogen receptor alpha (ERalpha) in interleukin (IL)1beta-treated rabbit articular chondrocytes in culture, and to determine the mechanisms of 17beta oestradiol (E2) effects on IL1beta-induced inducible nitric oxide synthase (iNOS) expression. METHODS The presence and functionality of ERalpha were investigated by immunocytochemistry and transient expression of an E2-responsive reporter construct. iNOS expression and production were determined by transient expression of a chimeric iNOS promoter-luciferase construct and protein immunoblotting. Nitric oxide (NO) production was determined by the Griess reaction. DNA-binding activities of nuclear factor-kappaB (NF-kappaB) and activated protein 1 were determined by electrophoretic mobility shift assay (EMSA)-ELISA assays. Nuclear translocation of p65 was studied by immunocytochemistry. RESULTS ERalpha was identified in the nucleus of chondrocytes. ERalpha efficiently transactivated a transiently expressed E2-responsive construct. On IL1beta treatment, ERalpha partially diffused from its nuclear localisation into the cytoplasm and its transactivation ability was impaired. Nevertheless, E2, tamoxifen and raloxifene efficiently inhibited IL1beta-induced NO production (-34%, -31% and -36%, respectively). E2 decreased IL1beta-induced iNOS protein expression (-40%). Transient expression of an iNOS promoter construct strongly suggested that iNOS expression was inhibited at the transcriptional level, and EMSA-ELISA assays showed that E2 reduced (-60%) the IL1beta-induced p65 DNA-binding capacity. Finally, the p65 nuclear translocation induced by IL1beta was also strongly decreased by E2. CONCLUSIONS Our data support a reciprocal antagonism between oestrogens and IL1beta, ultimately resulting in the decrease of cytokine-dependent NO production through transcriptional inhibition of iNOS expression. This effect was associated with selective inhibition of p65 DNA binding and nuclear translocation.
Collapse
Affiliation(s)
- Pascal Richette
- INSERM UMR-747, Universite Paris Descartes, UFR Biomedicale, Paris, France
| | | | | | | | | | | | | | | | | | | |
Collapse
|
77
|
Li RW, Meyer MJ, Van Tassell CP, Sonstegard TS, Connor EE, Van Amburgh ME, Boisclair YR, Capuco AV. Identification of estrogen-responsive genes in the parenchyma and fat pad of the bovine mammary gland by microarray analysis. Physiol Genomics 2006; 27:42-53. [PMID: 16788005 DOI: 10.1152/physiolgenomics.00032.2006] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Identification of estrogen-responsive genes is an essential step toward understanding mechanisms of estrogen action during mammary gland development. To identify these genes, 16 prepubertal heifers were used in a 2 × 2 factorial experiment, with ovarian status (intact or ovariectomized) as the first factor and estrogen treatment as the second (control or estradiol). Heifers were ovariectomized at ∼4.5 mo of age, and estrogen treatments were initiated 1 mo later. After 3 days of treatment, gene expression was analyzed in the parenchyma and fat pad of the bovine mammary gland using a high-density oligonucleotide microarray. Oligonucelotide probes represented 40,808 tentative consensus sequences from TIGR Bos taurus Gene Index and 4,575 singleton expressed sequence tags derived from libraries of pooled mammary gland and gut tissues. Microarray data were analyzed by use of the SAS mixed procedure, with an experiment-wide permutation-based significance level of P < 0.1. Considerable differences in basal gene expression were noted between mammary parenchyma and fat pad. A total of 124 estrogen-responsive genes were identified, with most responding only in the parenchyma or the fat pad. The majority of genes identified were not previously reported to be estrogen responsive. These undoubtedly include genes that are regulated indirectly but also include known estrogen-targeted genes and novel genes with potential estrogen-responsive elements in their promoter regions. The distinctive expression patterns regulated by estrogen in parenchyma and fat pad shed light on the need for both tissues to obtain normal mammary development.
Collapse
Affiliation(s)
- Robert W Li
- Bovine Functional Genomics Laboratory, United States Department of Agriculture-Agricultural Research Service, Beltsville, Maryland 20705, USA
| | | | | | | | | | | | | | | |
Collapse
|
78
|
Wang S, Lai K, Moy FJ, Bhat A, Hartman HB, Evans MJ. The nuclear hormone receptor farnesoid X receptor (FXR) is activated by androsterone. Endocrinology 2006; 147:4025-33. [PMID: 16675527 DOI: 10.1210/en.2005-1485] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Farnesoid X receptor (FXR) uses bile acids as endogenous ligands. Here, we demonstrate that androsterone, a metabolic product of testosterone, is also an FXR ligand. Treatment of castrated male mice with androsterone induced expression of the FXR target gene small heterodimer partner (SHP). In mouse AML-12 hepatocytes, chenodeoxycholic acid (CDCA) or androsterone induced SHP expression with a similar kinetic pattern. The FXR antagonist guggulsterone blocked the induction of SHP by androsterone in AML-12 cells. Nuclear magnetic resonance spectroscopy demonstrated the direct binding of androsterone to purified human FXR (hFXR) ligand-binding domain (LBD) protein, resulting in the recruitment of steroid receptor coactivator protein-1 (SRC-1) coactivator peptide. In HEK293 cells, androsterone activated gal4-mouse FXR-LBD and gal4-hFXR-LBD fusion proteins, although in contrast to CDCA, androsterone activation was significantly greater for the mouse FXR-LBD than for the hFXR-LBD. Site-directed mutagenesis of the hFXR-LBD defined amino acids Asn354 and Ser345 as critical for differential species sensitivity to CDCA and androsterone, respectively. Crystal structure studies suggest that the orientation of the steroid nucleus of bile acids within the binding pocket of FXR is reversed from all other nuclear hormone receptors. In support of this model, we show here that mutations M265I or R331H, residues predicted by crystal structure to interact with the carboxylic acid tail of CDCA but not with androsterone, altered CDCA activation but had no effect on androsterone activation. Activation of FXR by androsterone may provide an additional means for physiological or pharmacological modulation of FXR.
Collapse
Affiliation(s)
- Shuguang Wang
- Cardiovascular and Metabolic Disease Research, Wyeth Research, 500 Arcola Road, Collegeville, Pennsylvania 19426, USA
| | | | | | | | | | | |
Collapse
|
79
|
Tedeschi-Blok N, Lee M, Sison JD, Miike R, Wrensch M. Inverse association of antioxidant and phytoestrogen nutrient intake with adult glioma in the San Francisco Bay Area: a case-control study. BMC Cancer 2006; 6:148. [PMID: 16749939 PMCID: PMC1513391 DOI: 10.1186/1471-2407-6-148] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2006] [Accepted: 06/03/2006] [Indexed: 12/03/2022] Open
Abstract
Background Increasing evidence from epidemiologic studies suggest that oxidative stress may play a role in adult glioma. In addition to dietary antioxidants, antioxidant and weak estrogenic properties of dietary phytoestrogens may attenuate oxidative stress. Our hypothesis is that long-term consumption of dietary antioxidants and phytoestrogens such as genistein, daidzein, biochanin A, formononetin, matairesinol, secoisolariciresinol and coumestrol, may reduce the risk of adult glioma. Methods Using unconditional logistic regression models, we compared quartiles of consumption for several specific antioxidants and phytoestrogens among 802 adult glioma cases and 846 controls from two study series from the San Francisco Bay Area Adult Glioma Study, 1991 – 2000, controlling for vitamin supplement usage, age, socioeconomic status, gender, ethnicity and total daily calories. For cases, dietary information was either self-reported or reported by a proxy. For controls, dietary information was self-reported. Gender- and series- specific quartiles of average daily nutrient intake, estimated from food-frequency questionnaires, were computed from controls. Results Significant p-values (trend test) were evaluated using significance levels of either 0.05 or 0.003 (the Bonferroni corrected significance level equivalent to 0.05 adjusting for 16 comparisons). For all cases compared to controls, statistically significant inverse associations were observed for antioxidant index (p < 0.003), carotenoids (alpha- and beta-carotene combined, p < 0.05), daidzein (p = 0.003), matairesinol (p < 0.05), secoisolariciresinol (p < 0.003), and coumestrol (p < 0.003). For self-reported cases compared to controls, statistically significant inverse associations were observed for antioxidant index (p < 0.05) and daidzein (p < 0.05). Conclusion Our results support inverse associations of glioma with higher dietary antioxidant index and with higher intake of certain phytoestrogens, especially daidzein.
Collapse
Affiliation(s)
- Nicole Tedeschi-Blok
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, SRT 1015, MS 103, Children's Hospital Los Angeles, Los Angeles, USA
| | - Marion Lee
- Department of Epidemiology and Biostatistics, University of California San Francisco, School of Medicine, San Francisco, USA
| | - Jennette D Sison
- Department of Neurological Surgery, University of California San Francisco, School of Medicine, San Francisco, USA
| | - Rei Miike
- Department of Neurological Surgery, University of California San Francisco, School of Medicine, San Francisco, USA
| | - Margaret Wrensch
- Department of Neurological Surgery, University of California San Francisco, School of Medicine, San Francisco, USA
| |
Collapse
|
80
|
Liu SF, Malik AB. NF-kappa B activation as a pathological mechanism of septic shock and inflammation. Am J Physiol Lung Cell Mol Physiol 2006; 290:L622-L645. [PMID: 16531564 DOI: 10.1152/ajplung.00477.2005] [Citation(s) in RCA: 564] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The pathophysiology of sepsis and septic shock involves complex cytokine and inflammatory mediator networks. NF-kappaB activation is a central event leading to the activation of these networks. The role of NF-kappaB in septic pathophysiology and the signal transduction pathways leading to NF-kappaB activation during sepsis have been an area of intensive investigation. NF-kappaB is activated by a variety of pathogens known to cause septic shock syndrome. NF-kappaB activity is markedly increased in every organ studied, both in animal models of septic shock and in human subjects with sepsis. Greater levels of NF-kappaB activity are associated with a higher rate of mortality and worse clinical outcome. NF-kappaB mediates the transcription of exceptional large number of genes, the products of which are known to play important roles in septic pathophysiology. Mice deficient in those NF-kappaB-dependent genes are resistant to the development of septic shock and to septic lethality. More importantly, blockade of NF-kappaB pathway corrects septic abnormalities. Inhibition of NF-kappaB activation restores systemic hypotension, ameliorates septic myocardial dysfunction and vascular derangement, inhibits multiple proinflammatory gene expression, diminishes intravascular coagulation, reduces tissue neutrophil influx, and prevents microvascular endothelial leakage. Inhibition of NF-kappaB activation prevents multiple organ injury and improves survival in rodent models of septic shock. Thus NF-kappaB activation plays a central role in the pathophysiology of septic shock.
Collapse
Affiliation(s)
- Shu Fang Liu
- Div. of Pulmonary and Critical Care Medicine, Long Island Jewish Medical Center, RM B371, New Hyde Park, NY 11040, USA.
| | | |
Collapse
|
81
|
Rubio MF, Werbajh S, Cafferata EGA, Quaglino A, Coló GP, Nojek IM, Kordon EC, Nahmod VE, Costas MA. TNF-alpha enhances estrogen-induced cell proliferation of estrogen-dependent breast tumor cells through a complex containing nuclear factor-kappa B. Oncogene 2006; 25:1367-77. [PMID: 16331275 DOI: 10.1038/sj.onc.1209176] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Breast tumors are usually classified according to their response to estrogens as hormone-dependent or -independent. In this work, we investigated the role of the proinflammatory cytokine TNF-alpha on the estrogen-receptor-positive T47D breast ductal tumor cells. We have found that TNF-alpha exerts a mitogenic effect, inducing cyclin D1 expression and activation of the transcription factor NF-kappaB. Importantly, activation of NF-kappaB was required for estrogen-induced proliferation and cyclin D1 expression. TNF-alpha enhanced the estrogen response by increasing the levels and availability of NF-kappaB. Chromatin immunoprecipitation analysis suggested that the action of estrogens is mediated by a protein complex that contains the activated estrogen receptor, the nuclear receptor coactivator RAC3 and a member of the NF-kappaB family. Finally, our results demonstrate that activation of this transcription factor could be one of the key signals for estrogen-mediated response.
Collapse
Affiliation(s)
- M F Rubio
- Laboratorio de Biología Molecular y Apoptosis, Departamento de Sustancias Vasoactivas, Instituto de Investigaciones Médicas Alfredo Lanari, IDIM-CONICET, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina
| | | | | | | | | | | | | | | | | |
Collapse
|
82
|
Kalantaridou SN, Naka KK, Bechlioulis A, Makrigiannakis A, Michalis L, Chrousos GP. Premature ovarian failure, endothelial dysfunction and estrogen-progestogen replacement. Trends Endocrinol Metab 2006; 17:101-9. [PMID: 16515863 DOI: 10.1016/j.tem.2006.02.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2005] [Revised: 02/14/2006] [Accepted: 02/15/2006] [Indexed: 11/22/2022]
Abstract
Cardiovascular disease, including coronary artery disease, stroke and peripheral vascular disease, is the leading cause of death among women. Vascular endothelial dysfunction is an early marker of atherosclerosis. Women with premature ovarian failure (or premature menopause) present an increased risk for cardiovascular disease, which might be attributed to the early onset of vascular endothelial dysfunction, associated with sex steroid deficiency. Cyclical estrogen and progestogen therapy has been shown to restore endothelial function in these young women. Further research is required to assess primarily the long-term effects of hormone replacement therapy on cardiovascular and overall prognosis in young women with premature ovarian failure, as well as the effects of different doses, duration and routes of hormone administration in these women.
Collapse
Affiliation(s)
- Sophia N Kalantaridou
- Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, and Michaeleidion Cardiac Center, University of Ioannina Medical School, 45110 Ioannina, Greece.
| | | | | | | | | | | |
Collapse
|
83
|
Abstract
The unexpected discovery of a second form of the estrogen receptor (ER), designated ERbeta, surprised and energized the field of estrogen research. In the 9 yr since its identification, the remarkable efforts from academic and industrial scientists of many disciplines have made significant progress in elucidating its biology. A powerful battery of tools, including knockout mice as well as a panel of receptor-selective agonists, has allowed an investigation into the role of ERbeta. To date, in vivo efficacy studies are limited to rodents. Current data indicate that ERbeta plays a minor role in mediating estrogen action in the uterus, on the hypothalamus/pituitary, the skeleton, and other classic estrogen target tissues. However, a clear role for ERbeta has been established in the ovary, cardiovascular system, and brain as well as in several animal models of inflammation including arthritis, endometriosis, inflammatory bowel disease, and sepsis. The next phase of research will focus on elucidating, at a molecular level, how ERbeta exerts these diverse effects and exploring the clinical utility of ERbeta-selective agonists.
Collapse
Affiliation(s)
- Heather A Harris
- Women's Health and Musculoskeletal Biology, Wyeth Research, Collegeville, Pennsylvania 19426, USA.
| |
Collapse
|
84
|
Hardman MJ, Waite A, Zeef L, Burow M, Nakayama T, Ashcroft GS. Macrophage migration inhibitory factor: a central regulator of wound healing. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 167:1561-74. [PMID: 16314470 PMCID: PMC1613193 DOI: 10.1016/s0002-9440(10)61241-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Age-associated differences in estrogen levels critically modify the cutaneous wound healing response. Using a microarray-based approach, we profiled changes in gene expression within the wounds of mice that were wild type or null for the pro-inflammatory cytokine macrophage migration inhibitory factor (MIF) in the presence or absence of estrogen. This experimental design identified more than 600 differentially expressed genes and established MIF as a key player in the wound healing process, regulating many novel repair/inflammation-associated gene targets. Moreover, MIF affected virtually all of the effects of reduced estrogen on wound repair. In humans, serum and wound levels of MIF increased with age and were strongly down-regulated by estrogen in vivo. Estrogen-regulated MIF transcription in vitro via a nuclear factor kappaB-dependent mechanism. These findings have wide-ranging implications for the many pathophysiological states in which MIF plays an important regulatory role and suggest a potential therapeutic role for MIF in modulating clinical conditions associated with age-related decline in estrogen levels.
Collapse
|
85
|
Yang L, Hu Y, Hou Y. Effects of 17β-estradiol on the maturation, nuclear factor kappa B p65 and functions of murine spleen CD11c-positive dendritic cells. Mol Immunol 2006; 43:357-66. [PMID: 16310049 DOI: 10.1016/j.molimm.2005.02.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2005] [Accepted: 02/15/2005] [Indexed: 01/30/2023]
Abstract
Physiological gender differences in immune capabilities are now well recognized and suggest that sex steroid hormones such as estrogens may be involved in the regulation of the immunocompetence. In this paper, CD11c-positive murine spleen dendritic cells (SDCs) were treated with various concentrations of 17beta-estradiol (E2) for 24h. The viability, phenotype, nuclear factor kappa B p65 (NF-kappaBp65), endocytosis, stimulatory capacity and cytokine expression were analyzed. Our results showed that E2 increased the viability and MHC-II expression but decreased nuclear NF-kappaBp65 level and endocytosis of SDCs. E2 also increased the stimulatory capacity of SDCs from low-dose group but decreased it from middle- and high-dose ones. In addition, E2 increased the intracellular expression of IL-6 and IL-10 in SDCs, but no obvious change appeared in IL-12 and TNF-alpha. These data suggested that E2 might influence the immune responses by changing the viability, maturation, NF-kappaBp65, endocytosis, stimulatory capacity and cytokine expression of SDCs.
Collapse
Affiliation(s)
- Linsong Yang
- Immunology and Reproductive Biology Lab, Nanjing University, Nanjing 210093, PR China
| | | | | |
Collapse
|
86
|
Glidewell-Kenney C, Weiss J, Lee EJ, Pillai S, Ishikawa T, Ariazi EA, Jameson JL. ERE-independent ERalpha target genes differentially expressed in human breast tumors. Mol Cell Endocrinol 2005; 245:53-9. [PMID: 16298037 DOI: 10.1016/j.mce.2005.10.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2005] [Revised: 10/10/2005] [Accepted: 10/11/2005] [Indexed: 11/18/2022]
Abstract
The classical pathway for estrogen receptor (ER) signaling is mediated by ER binding to an estrogen response element (ERE) in DNA. ERalpha can also act via a nonclassical pathway by altering the activities of other transcription factors (e.g., Sp1, AP-1, or NF-kappaB) at their cognate sites on DNA. We previously generated a mutant form of ERalpha (E207A/G208A) that does not bind to EREs, and therefore lacks signaling via the classical pathway but retains signaling via the nonclassical pathway. In the current study, we introduce this mutant ERalpha into MDA-MB231 ERalpha-negative breast carcinoma cells to identify nonclassical pathway genes that respond to 17beta-estradiol (E2), selective estrogen receptor modulators (SERMs) tamoxifen (TAM) or raloxifene (RAL), or the estrogen antagonist ICI 182,780 (ICI). Consistent with a role for nonclassical signaling in SERM action, microarray analyses identify 268 responsive nonclassical ERalpha pathway target genes. ICI elicits the largest number of nonclassical genes, followed by RAL, TAM, and E2. Custom microarrays containing identified nonclassical ERalpha responsive genes are used to compare gene expression in human breast tumor (n = 34) and normal mammary epithelial cell (n = 9) samples. A subset of nonclassical genes (n = 32) are differentially expressed in breast tumors. In summary, we show that nonclassical ERalpha pathway target genes exhibit a range of transcriptional responses to SERMs and identify targets of this pathway as potentially relevant to breast cancer. The identification of nonclassical ERalpha target genes offers new insight into estrogen receptor signaling and cross talk with pathways that mediate breast tumor response to SERM therapy.
Collapse
Affiliation(s)
- Christine Glidewell-Kenney
- Division of Endocrinology, Metabolism & Molecular Medicine, Northwestern University, Feinberg School of Medicine, 251 E. Huron Street, Galter Pavilion Suite 3-150, Chicago, IL 60611, USA
| | | | | | | | | | | | | |
Collapse
|
87
|
Qin P, Borges-Marcucci LA, Evans MJ, Harnish DC. Bile acid signaling through FXR induces intracellular adhesion molecule-1 expression in mouse liver and human hepatocytes. Am J Physiol Gastrointest Liver Physiol 2005; 289:G267-73. [PMID: 15817812 DOI: 10.1152/ajpgi.00043.2005] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Previous studies have demonstrated a dramatic induction of inflammatory gene expression in livers from mice fed a high-fat, high-cholesterol diet containing cholate after 3-5 wk. To determine the contribution of cholate in mediating these inductions, C57BL/6 mice were fed a chow diet supplemented with increasing concentrations of cholic acid (CA) for 5 days. A dose-dependent induction in the hepatic levels of TNF-alpha, VCAM-1, ICAM-1, and SAA-2 mRNA were observed. As positive controls, a dose-dependent repression of cholesterol 7alpha-hydroxylase and a dose-dependent induction of small heterodimer partner (SHP) expression were also observed, suggesting that farnesoid X receptor (FXR) was activated. In addition, ICAM-1 and SHP mRNA levels were also induced in primary human hepatocytes when treated with chenodeoxycholic acid or GW4064, a FXR-selective agonist. The involvement of FXR in CA-induced inflammatory gene expression was further investigated in the human hepatic cell line HepG2. Both ICAM-1 and SHP expression were induced in a dose- and time-dependent manner by treatment with the FXR-selective agonist GW4064. Moreover, the induction of ICAM-1 by GW4064 was inhibited by the FXR antagonist guggulsterone or with transfection of FXR siRNA. Finally, the activity of FXR was mapped to a retinoic acid response element (RARE) site containing an imbedded farnesoid X response element (FXRE) on the human ICAM-1 promoter and FXR and retinoid X receptor were demonstrated to bind to this site. Finally, FXR-mediated activation of ICAM-1 could be further enhanced by TNF-alpha cotreatment in hepatocytes, suggesting a potential cooperation between cytokine and bile acid-signaling pathways during hepatic inflammatory events.
Collapse
Affiliation(s)
- Pu Qin
- Cardiovascular & Metabolic Disease Research, N2236, Wyeth Research, 500 Arcola Road, Collegeville, PA 19426, USA
| | | | | | | |
Collapse
|
88
|
Wang YX. Cardiovascular functional phenotypes and pharmacological responses in apolipoprotein E deficient mice. Neurobiol Aging 2005; 26:309-16. [PMID: 15639308 DOI: 10.1016/j.neurobiolaging.2004.06.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2003] [Revised: 06/08/2004] [Accepted: 06/30/2004] [Indexed: 11/16/2022]
Abstract
This is an overview of recent findings, mainly from our laboratory, describing the cardiovascular functional phenotypes and pharmacological responses in mice genetically deficient in apolipoprotein E (apoE-KO). ApoE-KO mice are hyperlipidemic and spontaneously develop atherosclerosis. We have detected several new cardiovascular functional phenotypes in apoE-KO mice: hyperglycemia, age-dependent aortic stiffening, cardiac hypertrophy and increased cardiac output. Angiotensin II (Ang II) promoted vascular inflammation and atherosclerosis, increased vascular stiffness, and induced abdominal aortic aneurysm (AAA) in apoE-KO mice, in which activation of NF-kappaB mediated pro-inflammatory genes plays an important role. Inhibition of nitric oxide (NO) synthesis with N(omega)-nitro-L-arginine methyl ester (L-NAME) significantly inhibited NO-mediated vascular responses and accelerated atherosclerosis in apoE-KO mice, supporting a protective role of NO against atherosclerosis. Estrogen attenuated atherosclerosis in apoE-KO mice, even in those with atherosclerosis being accelerated by Ang II, hyperglycemia, or L-NAME, demonstrating an anti-atherosclerotic effect of estrogen. Simvastatin paradoxically increased lipid and atherosclerosis in apoE-KO mice, but it decreased lipid and atherosclerosis in LDLR-KO mice, indicating that anti-atherosclerotic effect of simvastatin requires the presence of an intact apoE.
Collapse
Affiliation(s)
- Yi-Xin Wang
- Department of Pharmacology, Berlex Biosciences, P.O. Box 4099, 2600 Hilltop Drive, Richmond, CA 94804-0099, USA.
| |
Collapse
|
89
|
Beck V, Rohr U, Jungbauer A. Phytoestrogens derived from red clover: an alternative to estrogen replacement therapy? J Steroid Biochem Mol Biol 2005; 94:499-518. [PMID: 15876415 DOI: 10.1016/j.jsbmb.2004.12.038] [Citation(s) in RCA: 164] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2003] [Accepted: 12/14/2004] [Indexed: 11/21/2022]
Abstract
The benefits of plant extracts from soy and red clover as alternatives to conventional hormone replacement therapy (HRT) have been debated in the past. Here, an attempt has been made to summarize the biochemical and pharmacological data in the light of clinical aspects. Red clover and soy extracts contain isoflavones, which have a high affinity to estrogen receptor alpha (ERalpha), estrogen receptor beta (ERbeta), progesterone receptor (PR) and androgen receptor (AR). The higher affinity to ERbeta compared to ERalpha has been used as an explanation why red clover extracts function as food additives to treat menopausal disorders and may reduce risk of breast cancer. Biochemical analysis shows that these representatives of phytoestrogens have multiple actions beside selective estrogen receptor modulator (SERM)-activity. They act as selective estrogen enzyme modulators (SEEMs), have antioxidant activity and interact with transcription factors such as NF-kappaB. Furthermore, it is indicated that they have protective effects on osteoporosis and the cardiovascular system. Currently 40-50mg of isoflavones (biochanin A, daidzein, formononetin and genistein) are recommended as daily dose. This recommendation is based on the daily intake of phytoestrogens in a traditional Japanese diet.
Collapse
Affiliation(s)
- V Beck
- Department of Biotechnology, University of Natural Resources and Applied Life Sciences, Muthgasse 18, 1190 Vienna, Austria
| | | | | |
Collapse
|
90
|
Abstract
The NF-kappaB family of transcription factors regulates many genes that are essential primarily for the development, maintenance and function of the innate and adaptive immune systems. Thus, aberrant activity of the nuclear factor NF-kappaB has a role in many pathological conditions with inflammatory and autoimmune components. Estrogen receptors (ERs) are transcription factors that mediate the biological responses to the sex hormone estrogen and are essential for reproduction and for functions of the cardiovascular, skeletal and nervous systems. Recent studies have demonstrated molecular cross-talk between these families of transcription factors in which the ER mediates inhibition of NF-kappaB activity at several levels. Such cross-talk between these important regulators of the endocrine and immune systems might be exploited for the treatment of cancer and inflammatory and autoimmune diseases.
Collapse
Affiliation(s)
- Demetrios Kalaitzidis
- Boston University, Department of Biology, 5 Cummington Street, Boston, MA 02215, USA
| | | |
Collapse
|
91
|
Register TC, Cann JA, Kaplan JR, Williams JK, Adams MR, Morgan TM, Anthony MS, Blair RM, Wagner JD, Clarkson TB. Effects of soy isoflavones and conjugated equine estrogens on inflammatory markers in atherosclerotic, ovariectomized monkeys. J Clin Endocrinol Metab 2005; 90:1734-40. [PMID: 15585561 DOI: 10.1210/jc.2004-0939] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The effects of dietary soy isoflavones (IF) and conjugated equine estrogens (CEE) on circulating inflammatory markers were determined at the end of a 3-yr study of ovariectomized monkeys consuming a moderately atherogenic diet. Treatments were: 1) control, receiving alcohol-extracted soy-protein-based diet with low IF content (comparable to approximately 5 mg/d); 2) CEE, added to the control diet at a dose comparable to 0.625 mg/d; and 3) IF, consumed as a part of unextracted soy protein isolate at a dose comparable to 129 mg/d. Serum soluble vascular cell adhesion molecule-1 (sVCAM-1) was reduced by both IF (P < 0.006) and CEE (P < 0.0001) relative to controls. Serum monocyte chemoattractant protein (MCP)-1 was reduced by CEE (P < 0.0001) but not by IF (P = 1.00). Treatments did not affect serum IL-6 (P = 0.40), soluble E-selectin (P = 0.17), or C-reactive protein (P = 0.15). Serum MCP-1 and, to a lesser extent, IL-6 significantly correlated with atherosclerosis (plaque area) in the iliac and carotid arteries (all P < 0.05). Serum MCP-1 was also strongly associated with coronary artery atherosclerosis and with indices of plaque inflammation and matrix remodeling (matrix metalloproteinase-9) in the coronary artery intima (all P < 0.01). We conclude that, in this well-established nonhuman primate model of atherosclerosis, this dose of soy IF provided an antiinflammatory effect specific for sVCAM-1, whereas the effects of CEE extended to both sVCAM-1 and MCP1. It is possible that the atheroprotective effects of IF and CEE are mediated, at least in part, by effects on VCAM-1. The sites of IF inhibitory effects on sVCAM-1 production are not known, but likely candidates include the liver and/or the cardiovascular system.
Collapse
Affiliation(s)
- Thomas C Register
- Comparative Medicine Clinical Research Center, Wake Forest University School of Medicine, Medical Center Boulevard, Winston Salem, North Carolina 27157-1040, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
92
|
Klein SL, Cernetich A, Hilmer S, Hoffman EP, Scott AL, Glass GE. Differential expression of immunoregulatory genes in male and female Norway rats following infection with Seoul virus. J Med Virol 2005; 74:180-90. [PMID: 15258986 DOI: 10.1002/jmv.20163] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Males of many species are more susceptible than females to infections caused by parasites, bacteria, fungi, and viruses. Following inoculation with Seoul virus, male rats have more virus present in target organs and shed virus longer than females. The goal of this study was to test the hypothesis that variation in the expression of genes associated with immune function mediates sex differences in hantavirus infection. Using DNA microarrays, we examined changes in gene expression in lung tissue during the early (when animals are viremic and shedding virus; Day 15 post-inoculation (p.i.)) and late (animals have low levels of infectious virus, but high antibody titers; Day 40 p.i.) phases of infection in adult male and female rats. After normalizing the gene expression levels from infected animals to the gene expression levels from same-sex uninfected controls, our data revealed that 1,813 genes were differentially expressed between the sexes during infection. The expression of key transcriptional factors (e.g., eIF-2 alpha, NF-kappa B, IRF-1, NF-IL-6, and STAT6) and genes that encode for proinflammatory (e.g., TNF alpha R, IL-1R, and IL-1RAcP), antiviral (e.g., IFN gamma R and Mx proteins), T cell (e.g., CD3 and TCR), and Ig superfamily (e.g., IgM, IgG, and MHC class I and II) proteins was higher in females than males. Conversely, males had higher expression of heat shock protein genes (e.g., hsp70) suggesting that cellular stress is elevated in males. These data provide candidate genes and cellular pathways that may underlie sex differences in responses to Seoul virus and possibly other hemorrhagic fever viruses.
Collapse
Affiliation(s)
- Sabra L Klein
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, The Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland 21205, USA.
| | | | | | | | | | | |
Collapse
|
93
|
Chadwick CC, Chippari S, Matelan E, Borges-Marcucci L, Eckert AM, Keith JC, Albert LM, Leathurby Y, Harris HA, Bhat RA, Ashwell M, Trybulski E, Winneker RC, Adelman SJ, Steffan RJ, Harnish DC. Identification of pathway-selective estrogen receptor ligands that inhibit NF-kappaB transcriptional activity. Proc Natl Acad Sci U S A 2005; 102:2543-8. [PMID: 15699342 PMCID: PMC548967 DOI: 10.1073/pnas.0405841102] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Inflammation is now recognized as a key component in a number of diseases such as atherosclerosis, rheumatoid arthritis, and inflammatory bowel disease. The transcription factor NF-kappaB has been shown to be involved in both the early and late stages of the inflammatory-proliferative process. In this report, we describe the identification of the pathway-selective estrogen receptor (ER) ligand, WAY-169916, that inhibits NF-kappaB transcriptional activity but is devoid of conventional estrogenic activity. This pathway-selective ligand does not promote the classic actions of estrogens such as stimulation of uterine proliferation or ER-mediated gene expression, but is a potent antiinflammatory agent, as demonstrated in the HLA-B27 transgenic rat model of inflammatory bowel disease. Our results indicate the potential utility of pathway-selective ER ligands such as WAY-169916 in the treatment of chronic inflammatory diseases.
Collapse
Affiliation(s)
- Christopher C Chadwick
- Women's Health Research Institute and Departmens of Chemical and Screening Sciences, Wyeth Research, 500 Arcola Road, Collegeville, PA 19426, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
94
|
Jung ME, Gatch MB, Simpkins JW. Estrogen neuroprotection against the neurotoxic effects of ethanol withdrawal: potential mechanisms. Exp Biol Med (Maywood) 2005; 230:8-22. [PMID: 15618121 DOI: 10.1177/153537020523000102] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Ethanol withdrawal (EW) produces substantial neurotoxic effects, whereas estrogen is neuroprotective. Given observations that both human and nonhuman female subjects often show less impairment following EW, it is reasonable to hypothesize that estrogens may protect females from the neurotoxic effects of ethanol. This article is based on the assumption that the behavioral deficits seen following EW are produced in part by neuronal death triggered by oxidative insults produced by EW. The EW leads to activation of protein kinase C, especially PKCepsilon, which subsequently triggers apoptotic downstream events such as phosphorylation of nuclear factor-kappaB (NFkappaB) complex. On phosphorylation, active NFkappaB translocates to the nucleus, binds to DNA, and activates caspases, which trigger DNA fragmentation and apoptosis. In contrast, estrogens are antioxidant, inhibit overexpression of PKCepsilon, and suppress expression of NFkappaB and caspases. Estrogen treatment reduces the behavioral deficits seen during EW and attenuates molecular signals of apoptosis. The effects of ethanol and estrogen on each step in the signaling cascade from ethanol exposure to apoptosis are reviewed, and potential mechanisms by which estrogen could produce neuronal protection against the neurotoxicity produced by EW are identified. These studies serve as a guide for continuing research into the mechanisms of the neuroprotective effects of estrogen during EW and for the development of potential estrogen-based treatments for male and female alcoholics.
Collapse
Affiliation(s)
- M E Jung
- Department of Pharmacology and Neuroscience, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA.
| | | | | |
Collapse
|
95
|
Klein SL. Hormonal and immunological mechanisms mediating sex differences in parasite infection. Parasite Immunol 2004; 26:247-64. [PMID: 15541029 DOI: 10.1111/j.0141-9838.2004.00710.x] [Citation(s) in RCA: 442] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The prevalence and intensity of infections caused by protozoa, nematodes, trematodes, cestodes, and arthropods is higher in males than females. The primary thesis of this review is that immunological differences exist between the sexes that may underlie increased parasitism in males compared to females. Several field and laboratory studies link sex differences in immune function with circulating steroid hormones; thus, the roles of sex steroids, including testosterone, oestradiol, and progesterone, as well as glucocorticoids will be discussed. Not only can host hormones affect responses to infection, but parasites can both produce and alter hormone concentrations in their hosts. The extent to which changes in endocrine-immune interactions following infection are mediated by the host or the parasite will be considered. Although males are more susceptible than females to many parasites, there are parasites for which males are more resistant than females and endocrine-immune interactions may underlie this sex reversal. Finally, although immunological differences exist between the sexes, genetic and behavioural differences may explain some variability in response to infection and will be explored as alternative hypotheses for how differences between the sexes contribute to dimorphic responses to parasites.
Collapse
Affiliation(s)
- S L Klein
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology, The Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205-2179, USA.
| |
Collapse
|
96
|
Stenvinkel P, Lindholm B, Heimbürger O. POOR NUTRITIONAL STATUS AND INFLAMMATION: Novel Approaches in an Integrated Therapy of Inflammatory-Associated Wasting in End-Stage Renal Disease. Semin Dial 2004; 17:505-15. [PMID: 15660582 DOI: 10.1111/j.0894-0959.2004.17611.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
It is increasingly apparent that end-stage renal disease (ESRD) patients carry an inflammatory burden, which may play a pivotal role in the evolution of not only wasting, but also the massive increase in the relative risk of cardiovascular disease (CVD). Thus wasting is strongly associated with a persistent systemic inflammatory response, CVD, and impaired patient survival in end-stage renal disease (ESRD), as well as in other chronic diseases. Evidence suggests that a facilitative interaction between inflammatory cytokines and other factors such as poor appetite, comorbidity, acidosis, anemia, and hormonal derangements may cause wasting in this patient group. Clearly, isolated interventions in the form of nutritional energy and protein supplementation have seldom proven to be very effective in improving nutritional status and outcome in ESRD patients, presumably because of the need to attack other causative factors. Therefore, new treatment strategies must be evaluated. Strategies such as multiple appetite stimulants, various "anti-inflammatory diets," and new potentially useful anti-inflammatory pharmacologic agents may be tested alone, or in combination, to evaluate if these new therapeutic modalities can improve the outcome of ESRD patients. As the etiology of wasting in ESRD is multifactorial, we propose that its treatment must include not one, but a number of concomitant measures to provide an integrated therapy against this devastating complication.
Collapse
Affiliation(s)
- Peter Stenvinkel
- Division of Renal Medicine, Department of Clinical Science, Karolinska Institute, Karolinska University Hospital, S-141 86 Huddinge, Sweden.
| | | | | |
Collapse
|
97
|
Seo KH, Lee HS, Jung B, Ko HM, Choi JH, Park SJ, Choi IH, Lee HK, Im SY. Estrogen enhances angiogenesis through a pathway involving platelet-activating factor-mediated nuclear factor-kappaB activation. Cancer Res 2004; 64:6482-8. [PMID: 15374958 DOI: 10.1158/0008-5472.can-03-2774] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
In this study, we investigated the molecular events involved in estrogen-induced angiogenesis. Treatment of the human endometrial adenocarcinoma cells, HEC-1A, with estrogen up-regulated mRNA expression and protein synthesis of various angiogenic factors such as tumor necrosis factor-alpha, interleukin-1, basic fibroblast growth factor, and vascular endothelial growth factor. The estrogen-dependent induction of the expression was blocked by the platelet-activating factor (PAF) antagonists, WEB 2170. Estrogen treatment caused the activation of nuclear factor (NF)-kappaB in HEC-1A cells and was also blocked by PAF antagonist. Inhibitors of NF-kappaB activation inhibited estrogen-induced mRNA expression and protein synthesis of the angiogenic factors. Estrogen led to a pronounced angiogenesis as assessed by a mouse Matrigel model in vivo and endothelial cell sprouting in vitro. PAF antagonists or NF-kappaB inhibitors significantly inhibited this estrogen-dependent angiogenesis. Estrogen caused phospholipase A2 (PLA2) gene and protein expression. Estrogen-induced vascular endothelial growth factor mRNA expression and sprouting were significantly inhibited by PLA2 inhibitors, suggesting PLA2 expression is the upstream pathway in the estrogen-induced angiogenesis. Taken together, these results suggest that estrogen induces the production of angiogenic factors via a mechanism involving PAF-mediated NF-kappaB activation.
Collapse
Affiliation(s)
- Kook Heon Seo
- Department of Biological Sciences, The Institute of Basic Sciences, Hormone Research Center, Chonnam National University, Kwangju, Republic of Korea
| | | | | | | | | | | | | | | | | |
Collapse
|
98
|
Dijsselbloem N, Vanden Berghe W, De Naeyer A, Haegeman G. Soy isoflavone phyto-pharmaceuticals in interleukin-6 affections. Multi-purpose nutraceuticals at the crossroad of hormone replacement, anti-cancer and anti-inflammatory therapy. Biochem Pharmacol 2004; 68:1171-85. [PMID: 15313415 DOI: 10.1016/j.bcp.2004.05.036] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2004] [Accepted: 05/11/2004] [Indexed: 01/13/2023]
Abstract
Interleukin-6 is a pleiotropic cytokine which plays a crucial role in immune physiology and is tightly controlled by hormonal feedback mechanisms. After menopause or andropause, loss of the normally inhibiting sex steroids (estrogen, testosterone) results in elevated IL6 levels that are further progressively increasing with age. Interestingly, excessive IL6 production promotes tumorigenesis (breast, prostate, lung, colon, ovarian), and accounts for several disease-associated pathologies and phenotypical changes of advanced age, such as osteoporosis, rheumatoid arthritis, multiple myeloma, neurodegenerative diseases and frailty. In this respect, pharmacological modulation of IL6 gene expression levels may have therapeutical benefit in preventing cancer progression, ageing discomforts and restoring immune homeostasis. Although "plant extracts" are used in folk medicine within living memory, it is only since the 20th century that numerous scientific investigations have been performed to discover potential health-protective food compounds or "nutraceuticals" which might prevent cancer and ageing diseases. About 2000 years ago, Hippocrates already highlighted "Let food be your medicine and medicine be your food". Various nutrients in the diet play a crucial role in maintaining an "optimal" immune response, such that deficient or excessive intakes can have negative consequences on the organism's immune status and susceptibility to a variety of pathologies. Over the last few decades, various immune-modulating nutrients have been identified, which interfere with IL6 gene expression. Currently, a broad range of phyto-pharmaceuticals with a claimed hormonal activity, called "phyto-estrogens", is recommended for prevention of various diseases related to a disturbed hormonal balance (i.e. menopausal ailments and/or prostate/breast cancer). In this respect, there is a renewed interest in soy isoflavones (genistein, daidzein, biochanin) as potential superior alternatives to the synthetic selective estrogen receptor modulators (SERMs), which are currently applied in hormone replacement therapy (HRT). As phyto-chemicals integrate hormonal ligand activities and interference with signaling cascades, therapeutic use may not be restricted to hormonal ailments only, but may have applications in cancer chemoprevention and/or NF-kappaB-related inflammatory disorders as well.
Collapse
Affiliation(s)
- Nathalie Dijsselbloem
- Laboratory for Eukaryotic Gene Expression and Signal Transduction, Department of Molecular Biology, Ghent University, KL Ledeganckstraat 35, B-9000, Belgium
| | | | | | | |
Collapse
|
99
|
Kalaitzidis D, Ok J, Sulak L, Starczynowski DT, Gilmore TD. Characterization of a human REL-estrogen receptor fusion protein with a reverse conditional transforming activity in chicken spleen cells. Oncogene 2004; 23:7580-7. [PMID: 15326488 DOI: 10.1038/sj.onc.1207912] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Overexpression of the human REL transcription factor can malignantly transform chicken spleen cells in vitro. In this report, we have created and characterized a cDNA encoding a chimeric protein (RELDelta424-490-ER) in which sequences of a highly transforming REL mutant (RELDelta424-490) are fused to the ligand-binding domain of the human estrogen receptor (ER). Surprisingly, RELDelta424-490-ER is constitutively nuclear in A293 cells, and RELDelta424-490-ER activates transcription in the absence, but not in the presence, of estrogen in kappaB-site reporter gene assays. Furthermore, RELDelta424-490-ER transforms chicken spleen cells in the absence of estrogen, but the addition of estrogen blocks the ability of RELDelta424-490-ER-transformed cells to form colonies in soft agar, even though estrogen induces increased nuclear translocation of RELDelta424-490-ER in these cells. ERalpha can also inhibit REL-dependent transactivation in trans in an estrogen-dependent manner, and ERalpha can interact with REL in vitro. Thus, the RELDelta424-490-ER fusion protein shows an unusual, reverse hormone regulation, in that its most prominent biological activities (transformation and transactivation) are inhibited by estrogen, probably due to an estrogen-induced interaction between the ER sequences and sequences in the Rel homology domain. Nevertheless, these results indicate that the continual activity of REL is required to sustain the transformed state of chicken spleen cells in culture, suggesting that direct and specific inhibitors of REL may have therapeutic efficacy in certain human lymphoid cancers.
Collapse
|
100
|
Mukundan H, Resta TC, Kanagy NL. 17-β Estradiol Independently Regulates Erythropoietin Synthesis and NOS Activity during Hypoxia. J Cardiovasc Pharmacol 2004; 43:312-7. [PMID: 14716223 DOI: 10.1097/00005344-200402000-00023] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We reported previously that 17-beta estradiol (E2-beta) attenuates hypoxic induction of erythropoietin (EPO) synthesis in rats. We hypothesized this attenuation is mediated by increased nitric oxide (NO) bio-availability. To investigate this hypothesis, ovariectomized estrogen-depleted rats were instrumented with arterial and venous catheters and treated with either E2-beta (20 microg/24 hrs) or vehicle (polypropylene glycol) for 7 days. Rats were placed in Plexiglas boxes and administered a bolus of either the NO synthase inhibitor, Nomega-nitro-L-arginine (l-NNA, 15 mg/kg) or saline. Following this bolus, saline or l-NNA was continuously infused (15 mg/kg/h) throughout the 8 hours of hypoxic exposure (12% O2). Hypoxia increased plasma NO metabolites (NOx) in both saline groups but more in E2-beta-treated rats. l-NNA prevented this increase in both groups. Renal endothelial NO synthase (NOS) expression was unaltered by hypoxia, l-NNA, or E2-beta. Despite preventing increases in plasma NOx during hypoxia, l-NNA did not affect E2-beta attenuation of EPO synthesis. We conclude that E2-beta independently attenuates hypoxic induction of EPO and augments hypoxic increases in NO synthesis.
Collapse
Affiliation(s)
- Harshini Mukundan
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico, Health Sciences Center Albuquerque, New Mexico 87131, USA
| | | | | |
Collapse
|