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1.
Reprod Biol Endocrinol ; 18(1): 49, 2020 May 14.
Article in English | MEDLINE | ID: mdl-32408878

ABSTRACT

BACKGROUND: Cigarette smokers have a reduced risk of developing preeclampsia, possibly attributed to an increase in carbon monoxide (CO) levels. Carbon monoxide is a gasotransmitter that has been implicated in maintaining vascular tone, increasing angiogenesis, and reducing inflammation and apoptosis at physiological concentrations. Moderately increasing CO concentrations may have therapeutic potential to prevent or treat preeclampsia; however, the effects of CO on pregnancy are under studied. Our objective was to investigate the effect of CO on major angiogenic and inflammatory markers in pregnancy, and to evaluate the effect of CO on indicators of placental health. FINDINGS: Pregnant CD-1 mice were constantly exposed to either ambient air or 250 ppm CO from conception until gestation day (GD)10.5 or GD16.5. Using a qRT-PCR array, we identified that CO increased expression of major angiogenic genes at the implantation site on GD10.5, but not GD16.5. Pro-inflammatory cytokines in the plasma and tissue lysates from implantation sites in treated mice were not significantly different compared to controls. Additionally, CO did not alter the implantation site phenotype, in terms of proliferative capacity, invasiveness of trophoblasts, or abundance of uterine natural killer cells. CONCLUSIONS: This study suggests that CO exposure is pro-angiogenic at the maternal-fetal interface, and is not associated with demonstrable concerns during murine pregnancy. Future studies are required to validate safety and efficacy of CO as a potential therapeutic for vascular insufficiency diseases such as preeclampsia and intrauterine growth restriction.


Subject(s)
Adaptation, Physiological/drug effects , Carbon Monoxide/pharmacology , Neovascularization, Physiologic/drug effects , Placenta/drug effects , Uterus/drug effects , Adaptation, Physiological/genetics , Animals , Carbon Monoxide/toxicity , Carbon Monoxide Poisoning/genetics , Carbon Monoxide Poisoning/metabolism , Carbon Monoxide Poisoning/pathology , Carbon Monoxide Poisoning/physiopathology , Cytokines/metabolism , Embryo Implantation/drug effects , Embryo Implantation/genetics , Female , Gene Expression/drug effects , Male , Mice , Neovascularization, Pathologic/chemically induced , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/pathology , Neovascularization, Pathologic/physiopathology , Neovascularization, Physiologic/genetics , Placenta/blood supply , Placenta/metabolism , Placenta/pathology , Placental Circulation/drug effects , Placental Circulation/genetics , Pregnancy , Pregnancy Complications/genetics , Pregnancy Complications/metabolism , Pregnancy Complications/pathology , Pregnancy Complications/physiopathology , Uterus/blood supply , Uterus/metabolism , Uterus/pathology
2.
Microvasc Res ; 123: 92-98, 2019 05.
Article in English | MEDLINE | ID: mdl-30658063

ABSTRACT

Preeclampsia (PE) is characterized by systemic maternal endothelial dysfunction. Changes in endothelial reactivity have been reported before the onset of clinical signs of PE, and continuing into the post-partum period. Women who smoke during pregnancy have a 33% reduced risk of developing PE. This reduced risk is hypothesized to be, in part, attributed to carbon monoxide (CO), a by-product of cigarette combustion and a known endogenous vasodilator. Determining the vascular effects of CO in healthy women, may inform how CO can improve endothelial function and have promise as a novel therapeutic for PE. As part of a pilot study to determine the vascular effects of CO, the aim of this study was to measure microvascular vasodilation following low-dose CO inhalation. Non-pregnant women inhaled ambient room air or 250 ppm CO for 24 min during microvascular assessment using laser speckle contrast imaging. Changes in vascular flux were measured in the forearm before, during, and following a three-minute arterial occlusion. CO inhalation increased end-tidal breath CO (EtCO) (9.1 ±â€¯1.9 vs. 1.8 ±â€¯0.7 ppm, p < 0.05) and increased microvascular vasodilation, measured as difference of maximum level/resting level ratio (mean difference 0.476, 95% confidence interval (CI) = 0.149-0.802 vs. 0.118, 95% CI = -0.425-0.662, p < 0.05). Women who inhaled CO had a longer time to half recovery of endothelial function following arterial occlusion, compared to controls (hazard ratio 0.29, 95% CI = 0.10-0.91, p = 0.033). Inhalation of CO moderately increased EtCO and resulted in an increased microvascular response, suggesting that CO may have potential as a therapeutic for PE.


Subject(s)
Carbon Monoxide/administration & dosage , Microcirculation/drug effects , Microvessels/drug effects , Skin/blood supply , Vasodilation/drug effects , Vasodilator Agents/administration & dosage , Administration, Inhalation , Adult , Blood Flow Velocity , Case-Control Studies , Female , Forearm , Humans , Microvessels/physiology , Perfusion Imaging/methods , Pilot Projects , Regional Blood Flow , Time Factors , Young Adult
4.
Placenta ; 71: 6-12, 2018 11.
Article in English | MEDLINE | ID: mdl-30415746

ABSTRACT

INTRODUCTION: Smokers have a significantly decreased risk of pre-eclampsia (PE), possibly attributed to an increase in blood carbon monoxide (CO) concentrations. At physiological concentrations, CO has been demonstrated to have placental vasodilatory and anti-inflammatory properties. Increasing endogenous CO production may have therapeutic potential to either prevent or treat PE. Menadione (MD), synthetic vitamin K3, increases CO in rat microsomes. Our objective was to investigate MD's ability to increase endogenous CO concentrations in pregnancy. METHODS: Three experiments were completed. First, in vitro CO production was measured using isolated GD15 placentas. Second, non-pregnant normotensive mice received no, 1.5, 4.0 or 6.5 g/L MD for 7 days. Lastly, pregnant normotensive mice received either no or 6.5 g/L MD in water from GD10.5 to GD17.5. Consumption was measured as average daily water intake per gram of body weight. Maternal and fetal CO levels in the blood and tissue were quantified using headspace gas chromatography. RESULTS: MD significantly increased CO production in isolated GD15 placentas. In both pregnant and non-pregnant experiments, splenic CO, hepatic CO, and splenic mass were higher in treated mice compared to controls (all p < 0.05). Maternal %COHb and Hb in treated dams were not significantly different compared to controls. The fetal:placental mass ratio was significantly lower in the treatment group (p = 0.002). DISCUSSION: Placental CO production was observed in GD15 placentas after co-incubation with MD. MD administration increased CO in the liver and spleens of pregnant mice. Further investigation into different doses of MD is required to identify one without demonstrable fetal/placental effects.


Subject(s)
Carbon Monoxide/metabolism , Placenta/metabolism , Pre-Eclampsia/prevention & control , Vitamin K 3/therapeutic use , Vitamins/therapeutic use , Animals , Drug Evaluation, Preclinical , Female , Mice , Placenta/drug effects , Pregnancy , Pregnancy Outcome , Vitamin K 3/pharmacology , Vitamins/pharmacology
5.
Br J Cancer ; 119(4): 440-449, 2018 08.
Article in English | MEDLINE | ID: mdl-30046165

ABSTRACT

BACKGROUND: High-grade serous carcinoma (HGSC) of the ovary is predominantly diagnosed at late stages and primarily treated with debulking surgery followed by platinum/taxane-based chemotherapy. Although certain patients benefit significantly from currently used chemotherapy, there are patients who either do not respond or have an inadequate duration of response. We previously showed that tumours from chemoresistant patients have an immunosuppressed pre-existing tumour immune microenvironment with decreased expression of Type I Interferon (IFN1) genes. METHODS: Efficacy of a 'STimulator of INterferon Genes' agonist was evaluated in combination with carboplatin chemotherapy and PD-1 immune checkpoint blockade therapy in the ID8-Trp53-/- immunocompetent murine model of HGSC. RESULTS: Treatment with STING agonist led to decreased ascites accumulation and decreased tumour burden. Survival of mice treated with a combination of carboplatin, STING agonist and anti-PD-1 antibody was the longest. Tumour immune transcriptomic profiling revealed higher IFN response, antigen presentation and MHC II genes in tumours from STING agonist-treated mice compared to vehicle controls. Flow cytometry analysis revealed significantly higher intra-tumoural PD-1+ and CD69+CD62L-, CD8+ T cells in STING agonist-treated mice. CONCLUSIONS: These findings will enable rational design of clinical trials aimed at combinatorial approaches to improve chemotherapy response and survival in HGSC patients.


Subject(s)
Antibodies, Monoclonal/administration & dosage , Carboplatin/administration & dosage , Cystadenocarcinoma, Serous/drug therapy , Membrane Proteins/agonists , Ovarian Neoplasms/drug therapy , Animals , Antibodies, Monoclonal/pharmacology , Antibodies, Monoclonal, Humanized , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Carboplatin/pharmacology , Cell Line, Tumor , Cystadenocarcinoma, Serous/genetics , Cystadenocarcinoma, Serous/pathology , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic/drug effects , Humans , Mice , Neoplasm Grading , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Survival Analysis , Treatment Outcome , Tumor Burden/drug effects , Xenograft Model Antitumor Assays
6.
Gynecol Oncol ; 145(3): 436-445, 2017 06.
Article in English | MEDLINE | ID: mdl-28318643

ABSTRACT

OBJECTIVE: We recently established that high STAT1 expression and associated T helper type I tumour immune microenvironment (TME) are prognostic and chemotherapy response predictive biomarkers in high-grade serous ovarian cancer (HGSC). STAT1 induced chemokine CXCL10 is key to the recruitment of lymphocytes in the TME and is significantly highly expressed in the tumours from patients with longer survival. In the current study we therefore aimed to elucidate the role CXCL10 in disease progression and tumour immune transcriptomic alterations using the ID8 syngeneic murine model of HGSC. METHODS: ID8 ovarian cancer cells were engineered for stable knockdown (KD) and overexpression (OX) of CXCL10. The OX and KD cell line derivatives, along with their respective vector controls, were implanted in immunocompetent C57BL/6 mice via intra-peritoneal injections. At end point, immune transcriptomic profiling of tumour tissues and multiplex cytokine profiling of ascites, was performed. Effect of CXCL10 expression on the tumour vasculature and tumour cell proliferation was evaluated by CD31 and Ki67 immunostaining, respectively. RESULTS: Increased CXCL10 expression led to decreased tumour burden and malignant ascites accumulation in the ID8 syngeneic murine model of HGSC. The ascites levels of IL-6 and VEGF were significantly reduced in OX mice compared to the vector controls. The OX tumours also showed reduced vasculature (CD31) and proliferative index (Ki67) compared to the control tumours. Significantly higher expression of genes associated with antigen processing, apoptosis and T cell function was observed in OX tumours compared to the controls. Reduced CXCL10 expression in tumours from KD mice led to increased ascites accumulation and disease progression compared to the controls. CONCLUSION: CXCL10 is a positive determinant of anti-tumour immune responses in HGSC TME and disease progression. These findings are foundational for future translational studies aimed at improving treatment response and survival in HGSC patients, via exploiting the TME.


Subject(s)
Chemokine CXCL10/immunology , Cystadenocarcinoma, Serous/immunology , Ovarian Neoplasms/immunology , Tumor Microenvironment/immunology , Animals , Cell Line, Tumor , Cell Movement/immunology , Chemokine CXCL10/biosynthesis , Chemokine CXCL10/genetics , Cystadenocarcinoma, Serous/blood supply , Cystadenocarcinoma, Serous/genetics , Cystadenocarcinoma, Serous/pathology , Disease Progression , Female , Gene Knockdown Techniques , Mice , Mice, Inbred C57BL , Neoplasm Grading , Neovascularization, Pathologic/immunology , Neovascularization, Pathologic/pathology , Ovarian Neoplasms/blood supply , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Transcriptome
7.
J Pathol Clin Res ; 2(4): 259-270, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27917296

ABSTRACT

High-grade serous ovarian carcinoma (HGSC) accounts for 70% of all epithelial ovarian cancers but clinical management is challenged by a lack of accurate prognostic and predictive biomarkers of chemotherapy response. This study evaluated the role of Signal Transducer and Activator of Transcription 1 (STAT1) as an independent prognostic and predictive biomarker and its correlation with intratumoural CD8+ T cells in a second independent biomarker validation study. Tumour STAT1 expression and intratumoural CD8+ T cell infiltration were assessed by immunohistochemistry as a multicentre validation study conducted on 734 chemotherapy-naïve HGSCs. NanoString-based profiling was performed to correlate expression of STAT1 target genes CXCL9, CXCL10 and CXCL11 with CD8A transcript expression in 143 primary tumours. Multiplexed cytokine analysis of pre-treatment plasma from resistant and sensitive patients was performed to assess systemic levels of STAT1-induced cytokines. STAT1 was validated as a prognostic and predictive biomarker in both univariate and multivariate models and its expression correlated significantly with intra-epithelial CD8+ T cell infiltration in HGSC. STAT1 levels increased the prognostic and predictive value of intratumoural CD8+ T cells, confirming their synergistic role as biomarkers in HGSC. In addition, expression of STAT1 target genes (CXCL9, CXCL10 and CXCL11) correlated significantly with levels of, and CD8A transcripts from intratumoural CD8+ T cells within the resistant and sensitive tumours. Our findings provide compelling evidence that high levels of STAT1, STAT1-induced chemokines and CD8+ T cells correlate with improved chemotherapy response in HGSC. These results identify STAT1 and its target genes as novel biomarkers of chemosensitivity in HGSC. These findings provide new translational opportunities for patient stratification for immunotherapies based on emerging biomarkers of inflammation in HGSC. An improved understanding of the role of interferon-inducible genes will be foundational for developing immunomodulatory therapies in ovarian cancer.

8.
Mol Hum Reprod ; 22(2): 130-42, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26646502

ABSTRACT

STUDY HYPOTHESIS: Placental growth factor (PGF) is expressed in the developing mouse brain and contributes to vascularization and vessel patterning. STUDY FINDING: PGF is dynamically expressed in fetal mouse brain, particularly forebrain, and is essential for normal cerebrovascular development. WHAT IS KNOWN ALREADY: PGF rises in maternal plasma over normal human and mouse pregnancy but is low in many women with the acute onset hypertensive syndrome, pre-eclampsia (PE). Little is known about the expression of PGF in the fetus during PE. Pgf  (-/-) mice appear normal but recently cerebral vascular defects were documented in adult Pgf  (-/-) mice. STUDY DESIGN, SAMPLES/MATERIALS, METHODS: Here, temporal-spatial expression of PGF is mapped in normal fetal mouse brains and cerebral vasculature development is compared between normal and congenic Pgf  (-/-) fetuses to assess the actions of PGF during cerebrovascular development. Pgf/PGF, Vegfa/VEGF, Vegf receptor (Vegfr)1 and Vegfr2 expression were examined in the brains of embryonic day (E)12.5, 14.5, 16.5 and 18.5 C57BL/6 (B6) mice using quantitative PCR and immunohistochemistry. The cerebral vasculature was compared between Pgf  (-/-) and B6 embryonic and adult brains using whole mount techniques. Vulnerability to cerebral ischemia was investigated using a left common carotid ligation assay. MAIN RESULTS AND THE ROLE OF CHANCE: Pgf/PGF and Vegfr1 are highly expressed in E12.5-14.5 forebrain relative to VEGF and Vegfr2. Vegfa/VEGF is relatively more abundant in hindbrain (HB). PGF and VEGF expression were similar in midbrain. Delayed HB vascularization was seen at E10.5 and 11.5 in Pgf  (-/-) brains. At E14.5, Pgf  (-/-) circle of Willis showed unilateral hypoplasia and fewer collateral vessels, defects that persisted post-natally. Functionally, adult Pgf  (-/-) mice experienced cerebral ischemia after left common carotid arterial occlusion while B6 mice did not. LIMITATIONS, REASONS FOR CAUTION: Since Pgf  (-/-) mice were used, consequences of complete absence of maternal and fetal PGF were defined. Therefore, the effects of maternal versus fetal PGF deficiency on cerebrovascular development cannot be separated. However, as PGF was strongly expressed in the developing brain at all timepoints, we suggest that local PGF has a more important role than distant maternal or placental sources. Full PGF loss is not expected in PE pregnancies, predicting that the effects of PGF deficiency identified in this model will be more severe than any effects in PE-offspring. WIDER IMPLICATIONS OF THE FINDINGS: These studies provoke the question of whether PGF expression is decreased and cerebral vascular maldevelopment occurs in fetuses who experience a preeclamptic gestation. These individuals have already been reported to have elevated risk for stroke and cognitive impairments. LARGE SCALE DATA: N/A. STUDY FUNDING AND COMPETING INTERESTS: This work was supported by awards from the Natural Sciences and Engineering Research Council, the Canada Research Chairs Program and the Canadian Foundation for Innovation to B.A.C. and by training awards from the Universidade Federal de Pernambuco and Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), Brazil to R.L.L.; Queen's University to V.R.K. and the Canadian Institutes of Health Research to M.T.R. The work of P.C. is supported by the Belgian Science Policy BELSPO-IUAP7/03, Structural funding by the Flemish Government-Methusalem funding, and the Flemish Science Fund-FWO grants. There were no competing interests.


Subject(s)
Brain Ischemia/genetics , Brain/metabolism , Coronary Stenosis/genetics , Neovascularization, Pathologic/genetics , Pregnancy Proteins/deficiency , Animals , Brain/blood supply , Brain/pathology , Brain Ischemia/metabolism , Brain Ischemia/pathology , Carotid Artery, Common/metabolism , Carotid Artery, Common/pathology , Coronary Stenosis/metabolism , Coronary Stenosis/pathology , Disease Models, Animal , Embryo, Mammalian , Female , Fetus , Gene Expression Regulation , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , Neovascularization, Pathologic/metabolism , Neovascularization, Pathologic/pathology , Placenta Growth Factor , Pre-Eclampsia/genetics , Pre-Eclampsia/metabolism , Pre-Eclampsia/pathology , Pregnancy , Pregnancy Proteins/genetics , Signal Transduction , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor Receptor-1/genetics , Vascular Endothelial Growth Factor Receptor-1/metabolism , Vascular Endothelial Growth Factor Receptor-2/genetics , Vascular Endothelial Growth Factor Receptor-2/metabolism
9.
Mol Cell Biochem ; 408(1-2): 223-33, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26169981

ABSTRACT

The maternal system is challenged with many physiological changes throughout pregnancy to prepare the body to meet the metabolic needs of the fetus and for delivery. Many pregnancies, however, are faced with pathological stressors or complications that significantly impact maternal health. A shift in this paradigm is now beginning to investigate the implication of pregnancy complications on the fetus and their continued influence on offspring disease risk into adulthood. In this investigation, we sought to determine whether maternal hypertension during pregnancy alters the cerebral response of adult offspring to acute ischemic stroke. Atrial natriuretic peptide gene-disrupted (ANP(-/-)) mothers exhibit chronic hypertension that escalates during pregnancy. Through comparison of heterozygote offspring born from either normotensive (ANP(+/-WT)) or hypertensive (ANP(+/-KO)) mothers, we have demonstrated that offspring exposed to maternal hypertension exhibit larger cerebral infarct volumes following middle cerebral artery occlusion. Observation of equal baseline cardiovascular measures, cerebrovascular structure, and cerebral blood volumes between heterozygote offspring suggests no added influences on offspring that would contribute to adverse cerebral response post-stroke. Cerebral mRNA expression of endothelin and nitric oxide synthase vasoactive systems demonstrated up-regulation of Et-1 and Nos3 in ANP(+/-KO) mice and thus an enhanced acute vascular response compared to ANP(+/-WT) counterparts. Gene expression of Na(+)/K(+) ATPase channel isoforms, Atp1a1, Atp1a3, and Atp1b1, displayed no significant differences. These investigations are the first to demonstrate a fetal programming effect between maternal hypertension and adult offspring stroke outcome. Further mechanistic studies are required to complement epidemiological evidence of this phenomenon in the literature.


Subject(s)
Atrial Natriuretic Factor/genetics , Cerebral Infarction/pathology , Hypertension, Pregnancy-Induced/genetics , Prenatal Exposure Delayed Effects/pathology , Adult Children , Animals , Cerebral Infarction/etiology , Cerebral Infarction/genetics , Disease Models, Animal , Endothelins/genetics , Female , Humans , Mice , Nitric Oxide Synthase/genetics , Pregnancy , Prenatal Exposure Delayed Effects/etiology , Prenatal Exposure Delayed Effects/genetics
10.
Mol Cancer ; 14: 85, 2015 Apr 15.
Article in English | MEDLINE | ID: mdl-25889730

ABSTRACT

BACKGROUND: Among women worldwide, breast cancer is the most commonly diagnosed cancer, and the second leading cause of cancer-related deaths. Improved understanding of breast tumourigenesis may facilitate the development of more effective therapies. Peroxisome proliferator-activated receptor (PPAR)γ is a transcription factor that regulates genes involved in insulin sensitivity and adipogenesis. Previously, we showed, using 7,12-dimethylbenz [a] anthracene (DMBA)-treated haploinsufficient PPARγ mice, that PPARγ suppresses breast tumour progression; however, the PPARγ expressing cell types and mechanisms involved remain to be clarified. Here, the role of PPARγ expression and activation in mammary epithelial cells (MG) with respect to DMBA-mediated breast tumourigenesis was investigated. METHODS: PPARγ MG knockout (PPARγ-MG KO) mice and their congenic, wild-type controls (PPARγ-WT) were treated once a week for six weeks by oral gavage with 1 mg DMBA dissolved in corn oil and maintained on a normal chow diet. At week 7, mice were randomly divided into those maintained on a normal chow diet (DMBA Only; PPARγ-WT: n = 25 and PPARγ-MG KO: n = 39) or those receiving a diet supplemented with the PPARγ ligand, rosiglitazone (ROSI, 4 mg/kg/day) (DMBA + ROSI; PPARγ-WT: n = 34 and PPARγ-MG KO: n = 17) for the duration of the 25-week study. RESULTS: Compared to DMBA Only-treated PPARγ-WTs, both breast tumour susceptibility and serum levels of proinflammatory and chemotactic cytokines, namely IL-4, eotaxin, GM-CSF, IFN-γ, and MIP-1α, were decreased among PPARγ-MG KOs. Cotreatment with ROSI significantly reduced breast tumour progression among PPARγ-WTs, correlating with increased BRCA1 and decreased VEGF and COX-2 protein expression levels in breast tumours; whereas, surprisingly DMBA + ROSI-treated PPARγ-MG KOs showed increased breast tumourigenesis, correlating with activation of COX-2. CONCLUSION: These novel data suggest MG-specific PPARγ expression and signaling is critical during breast tumourigenesis, and may serve as a strong candidate predictive biomarker for response of breast cancer patients to the use of therapeutic strategies that include PPARγ ligands.


Subject(s)
Disease Progression , Epithelial Cells/metabolism , Mammary Glands, Animal/metabolism , Mammary Neoplasms, Animal/metabolism , Mammary Neoplasms, Experimental/metabolism , PPAR gamma/metabolism , Signal Transduction , 9,10-Dimethyl-1,2-benzanthracene , Animals , BRCA1 Protein/metabolism , Cytokines/blood , Epithelial Cells/pathology , Female , Gene Deletion , Mammary Glands, Animal/pathology , Mammary Neoplasms, Animal/blood , Mammary Neoplasms, Animal/pathology , Mammary Neoplasms, Experimental/blood , Mammary Neoplasms, Experimental/pathology , Mice, Knockout , Models, Biological , Organ Specificity , Tumor Burden
11.
Mol Cell Biochem ; 399(1-2): 39-47, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25391363

ABSTRACT

Investigations regarding hypertension and dietary sodium, both factors that influence stroke risk, have previously been limited to using genetically disparate treatment and control groups, namely the stroke-prone, spontaneously hypertensive rat and Wistar-Kyoto rat. In this investigation, we have characterized and compared cerebral vasoactive system adaptations following stroke in genetically identical, salt-induced hypertensive, and normotensive control mice. Briefly, ANP(+/-) (C57BJ/6 × SV129 background) mice were fed chow containing either 0.8% NaCl (NS) or 8.0% NaCl (HS) for 7 weeks. Transient cerebral ischemia was induced by middle cerebral artery occlusion (MCAO). Infarct volumes were measured 24-h post-reperfusion and the mRNA expression of five major vasoactive systems was characterized using qPCR. Along with previous publications, our data validate a salt-induced hypertensive state in ANP(+/-) mice fed HS chow as they displayed left ventricular hypertrophy, increased systolic blood pressure, and increased urinary sodium excretion. Following MCAO, mice fed HS exhibited larger infarct volumes than their dietary counterparts. In addition, significant up-regulation in Et-1 and Nos3 mRNA expression in response to salt and stroke suggests implications with increased cerebral damage in this group. In conclusion, our data demonstrate increased cerebral susceptibility to stroke in salt-induced hypertensive mice. More importantly, however, we have characterized a novel method of investigating hypertension and stroke with the use of genetically identical treatment and control groups. This is the first investigation in which genetic confounding variables have been eliminated.


Subject(s)
Cerebrovascular Circulation , Hypertension/physiopathology , Stroke/physiopathology , Animals , Circle of Willis/physiopathology , Female , Gene Expression , Hypertension/etiology , Hypertrophy, Left Ventricular/etiology , Hypertrophy, Left Ventricular/physiopathology , Hypoxia-Ischemia, Brain/physiopathology , Infarction, Middle Cerebral Artery/physiopathology , Male , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Transgenic , Neovascularization, Physiologic , Sodium Chloride, Dietary/adverse effects , Vascular Endothelial Growth Factor A/physiology
12.
Int J Cancer ; 134(5): 1055-66, 2014 Mar 01.
Article in English | MEDLINE | ID: mdl-23934545

ABSTRACT

Breast cancer is the leading cause of new cancer diagnoses among women. Using peroxisome proliferator-activated receptor (PPAR)γ((+/-)) mice, we showed normal expression of PPARγ was critical to stop 7,12-dimethylbenz[a]anthracene (DMBA)-induced breast tumorigenesis. PPARγ is expressed in many breast cell types including mammary secretory epithelial (MSE) cells. MSEs proliferate as required during pregnancy, and undergo apoptosis or reversible transdifferentiation during involution once lactation is complete. Thus, MSE-specific loss of PPARγ was hypothesized to enhance DMBA-mediated breast tumorigenesis. To test this, MSE cell-specific PPARγ knockout (PPARγ-MSE KO) and control (PPARγ-WT) mice were generated, mated and allowed to nurse for three days. One week after involution, dams were treated with DMBA to initiate breast tumors, and randomized on week 7 to continue receiving a normal chow diet (DMBA Only: PPARγ-WT, n = 15; PPARγ-MSE KO, n = 25) or one supplemented with a PPARγ activating drug (DMBA + ROSI: PPARγ-WT, n = 17; PPARγ-MSE KO, n = 24), and monitored for changes in breast tumor outcomes. PPARγ-MSE KOs had significantly lower overall survival and decreased mammary tumor latency as compared to PPARγ-WT controls. PPARγ activation significantly reduced DMBA-mediated malignant mammary tumor volumes irrespective of genotype. MSE-specific PPARγ loss resulted in decreased mammary gland expression of PTEN and Bax, increased superoxide anion production, and elevated serum eotaxin and RANTES, creating a protumorigenic environment. Moreover, PPARγ activation in MSEs delayed mammary tumor growth in part by down-regulating Cox-1, Cox-2 and cyclin D1. Collectively, these studies highlight a protective role of MSE-specific PPARγ during breast tumorigenesis, and support a novel chemotherapeutic role of PPARγ activation in breast cancer.


Subject(s)
Mammary Glands, Animal/metabolism , Mammary Neoplasms, Experimental/etiology , PPAR gamma/physiology , 9,10-Dimethyl-1,2-benzanthracene , Animals , Epithelial Cells/metabolism , Female , Mammary Neoplasms, Experimental/metabolism , Mice , Mice, Knockout , PTEN Phosphohydrolase/analysis , bcl-2-Associated X Protein/analysis
13.
J Biomol Tech ; 24(1): 39-49, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23542132

ABSTRACT

As part of the DNA Sequencing Research Group of the Association of Biomolecular Resource Facilities, we have tested the reproducibility of the Roche/454 GS-FLX Titanium System at five core facilities. Experience with the Roche/454 system ranged from <10 to >340 sequencing runs performed. All participating sites were supplied with an aliquot of a common DNA preparation and were requested to conduct sequencing at a common loading condition. The evaluation of sequencing yield and accuracy metrics was assessed at a single site. The study was conducted using a laboratory strain of the Dutch elm disease fungus Ophiostoma novo-ulmi strain H327, an ascomycete, vegetatively haploid fungus with an estimated genome size of 30-50 Mb. We show that the Titanium System is reproducible, with some variation detected in loading conditions, sequencing yield, and homopolymer length accuracy. We demonstrate that reads shorter than the theoretical minimum length are of lower overall quality and not simply truncated reads. The O. novo-ulmi H327 genome assembly is 31.8 Mb and is comprised of eight chromosome-length linear scaffolds, a circular mitochondrial conti of 66.4 kb, and a putative 4.2-kb linear plasmid. We estimate that the nuclear genome encodes 8613 protein coding genes, and the mitochondrion encodes 15 genes and 26 tRNAs.


Subject(s)
High-Throughput Nucleotide Sequencing/methods , Mycoses/genetics , Ophiostoma/genetics , Ulmus/genetics , Base Sequence , Genome, Fungal , Mycoses/microbiology , Plant Diseases/genetics , Plant Diseases/microbiology , Ulmus/microbiology
14.
Carcinogenesis ; 33(7): 1412-20, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22581835

ABSTRACT

Peroxisome proliferator-activated receptor (PPAR)γ regulates the expression of genes essential for fat storage, primarily through its activity in adipocytes. It also has a role in carcinogenesis. PPARγ normally stops the in vivo progression of 7,12-dimethylbenz[a]anthracene (DMBA)-mediated breast tumours as revealed with PPARγ haploinsufficient mice. Since many cell types associated with the mammary gland express PPARγ, each with unique signal patterns, this study aimed to define which tissues are required for PPARγ-dependent antitumour effects. Accordingly, adipocyte-specific PPARγ knockout (PPARγ-A KO) mice and their wild-type (PPARγ-WT) controls were generated, and treated with DMBA for 6 weeks to initiate breast tumorigenesis. On week 7, mice were randomized to continue on normal chow diet or one supplemented with rosiglitazone (ROSI), and followed for 25 weeks for tumour outcomes. In PPARγ-A KO versus PPARγ-WT mice, malignant mammary tumour incidence was significantly higher and mammary tumour latency was decreased. DMBA + ROSI treatment reduced average mammary tumour volumes by 50%. Gene expression analyses of mammary glands by quantitative real-time polymerase chain reaction and immunofluorescence indicated that untreated PPARγ-A KOs had significantly decreased BRCA1 expression in mammary stromal adipocytes. Compared with PPARγ-WT mice, serum leptin levels in PPARγ-A KOs were also significantly higher throughout the study. Together, these data are the first to suggest that in vivo PPARγ expression in mammary stromal adipocytes attenuates breast tumorigenesis through BRCA1 upregulation and decreased leptin secretion. This study supports a protective effect of activating PPARγ as a novel chemopreventive therapy for breast cancer.


Subject(s)
Adipocytes/metabolism , Mammary Neoplasms, Experimental/prevention & control , PPAR gamma/physiology , Stromal Cells/metabolism , Animals , Base Sequence , DNA Primers , Enzyme-Linked Immunosorbent Assay , Female , Mice , Mice, Knockout , PPAR gamma/genetics , Real-Time Polymerase Chain Reaction , Rosiglitazone , Thiazolidinediones/administration & dosage
15.
PLoS One ; 6(10): e27021, 2011.
Article in English | MEDLINE | ID: mdl-22046435

ABSTRACT

Mammalian hibernation is a complex phenotype involving metabolic rate reduction, bradycardia, profound hypothermia, and a reliance on stored fat that allows the animal to survive for months without food in a state of suspended animation. To determine the genes responsible for this phenotype in the thirteen-lined ground squirrel (Ictidomys tridecemlineatus) we used the Roche 454 platform to sequence mRNA isolated at six points throughout the year from three key tissues: heart, skeletal muscle, and white adipose tissue (WAT). Deep sequencing generated approximately 3.7 million cDNA reads from 18 samples (6 time points ×3 tissues) with a mean read length of 335 bases. Of these, 3,125,337 reads were assembled into 140,703 contigs. Approximately 90% of all sequences were matched to proteins in the human UniProt database. The total number of distinct human proteins matched by ground squirrel transcripts was 13,637 for heart, 12,496 for skeletal muscle, and 14,351 for WAT. Extensive mitochondrial RNA sequences enabled a novel approach of using the transcriptome to construct the complete mitochondrial genome for I. tridecemlineatus. Seasonal and activity-specific changes in mRNA levels that met our stringent false discovery rate cutoff (1.0 × 10(-11)) were used to identify patterns of gene expression involving various aspects of the hibernation phenotype. Among these patterns are differentially expressed genes encoding heart proteins AT1A1, NAC1 and RYR2 controlling ion transport required for contraction and relaxation at low body temperatures. Abundant RNAs in skeletal muscle coding ubiquitin pathway proteins ASB2, UBC and DDB1 peak in October, suggesting an increase in muscle proteolysis. Finally, genes in WAT that encode proteins involved in lipogenesis (ACOD, FABP4) are highly expressed in August, but gradually decline in expression during the seasonal transition to lipolysis.


Subject(s)
Adaptation, Physiological/genetics , Hibernation/genetics , High-Throughput Nucleotide Sequencing , Seasons , Transcriptome/genetics , Animals , Gene Expression Regulation/physiology , High-Throughput Nucleotide Sequencing/methods , Humans , Lipogenesis/genetics , Mammals , Muscles/metabolism , Peptide Hydrolases/genetics , Sciuridae
16.
AMIA Annu Symp Proc ; : 400-4, 2005.
Article in English | MEDLINE | ID: mdl-16779070

ABSTRACT

We study how Metropolitan Medical Response System units conceptualize the physical space of a disaster and their organized response. Using a variety of ethnographic methods before, during, and after a disaster drill, we have developed an initial ontology for geospatial and context-aware technology. The conceptual map of first responders is far more complex than a geographical map. Zones and Areas are used to describe documented concepts critical to MMRS operations. Ad hoc locations also play a critical role, helping first responders communicate tactics in spatial terms. Such distinctions play an important role in the way our experts think about their activity. Successful geoaware alerting systems must incorporate these notions if they are to seamlessly fit into the work flow of first responders.


Subject(s)
Disaster Planning/organization & administration , Emergency Medical Service Communication Systems , Emergency Medical Services/organization & administration , Geography , Rescue Work/organization & administration , Terrorism , Cognition , Geographic Information Systems , Humans , Internet , Nuclear Warfare , Warfare
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