5 research outputs found

    PARP inhibition by olaparib or gene knockout blocks asthma-like manifestation in mice by modulating CD4+ T cell function

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    Background: An important portion of asthmatics do not respond to current therapies. Thus, the need for new therapeutic drugs is urgent. We have demonstrated a critical role for PARP in experimental asthma. Olaparib, a PARP inhibitor, was recently introduced in clinical trials against cancer. The objective of the present study was to examine the efficacy of olaparib in blocking established allergic airway inflammation and hyperresponsiveness similar to those observed in human asthma in animal models of the disease. Methods: We used ovalbumin (OVA)-based mouse models of asthma and primary CD4+ T cells. C57BL/6J WT or PARP-1-/- mice were subjected to OVA sensitization followed by a single or multiple challenges to aerosolized OVA or left unchallenged. WT mice were administered, i.p., 1 mg/kg, 5 or 10 mg/kg of olaparib or saline 30 min after each OVA challenge. Results: Administration of olaparib in mice 30 min post-challenge promoted a robust reduction in airway eosinophilia, mucus production and hyperresponsiveness even after repeated challenges with ovalbumin. The protective effects of olaparib were linked to a suppression of Th2 cytokines eotaxin, IL-4, IL-5, IL-6, IL-13, and M-CSF, and ovalbumin-specific IgE with an increase in the Th1 cytokine IFN-\u3b3. These traits were associated with a decrease in splenic CD4+ T cells and concomitant increase in T-regulatory cells. The aforementioned traits conferred by olaparib administration were consistent with those observed in OVA-challenged PARP-1-/- mice. Adoptive transfer of Th2-skewed OT-II-WT CD4+ T cells reversed the Th2 cytokines IL-4, IL-5, and IL-10, the chemokine GM-CSF, the Th1 cytokines IL-2 and IFN-\u3b3, and ovalbumin-specific IgE production in ovalbumin-challenged PARP-1-/-mice suggesting a role for PARP-1 in CD4+ T but not B cells. In ex vivo studies, PARP inhibition by olaparib or PARP-1 gene knockout markedly reduced CD3/CD28-stimulated gata-3 and il4 expression in Th2-skewed CD4+ T cells while causing a moderate elevation in t-bet and ifn-\u3b3 expression in Th1-skewed CD4+ T cells. Conclusions: Our findings show the potential of PARP inhibition as a viable therapeutic strategy and olaparib as a likely candidate to be tested in human asthma clinical trials

    Diagnostic performance of Multislice Computed Tomography in evaluation of coronary artery bypass grafts in diabetic and non-diabetic patients

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    We sought to evaluate the diagnostic accuracy of noninvasive dual-source multi-slice computed tomography (MSCT) angiography in the assessment of graft patency and degree of stenosis in patients after coronary artery bypass grafting (CABG). Background: Assessment of bypass grafts body and their anastomotic sites by invasive coronary angiography have a risk of potentially life-threatening complications and often require extra procedure time, contrast load, and radiation exposure. Methods: 64-dual-source MSCT was performed to 51 (49 men, mean age 58.6 ± 8 years, range from 38 to 76) post-CABG symptomatic patients. Control of heart rate was done with oral beta blockers, sublingual nitrates was given 2-3 min before the scan. Mean interval between CABG surgery and MSCT was 73.41 ± 65.84 (range 3 to 252) months. Mean heart rate during scanning was 62.5 ± 13.2 (range 52–72) beats/min. Ninety-four percent of patients had both arterial and venous grafts. A total of 142 graft body and 142 anastomotic sites were analyzed. Two grafts body and 4 anastomotic sites were excluded because they were non-evaluable by MSCT. A semi-quantitative assessment of the graft stenosis severity was done according to the recommendation of the Society of Cardiovascular Computed Tomography (SCCT) A significant stenosis was defined as equal to or >70%, moderate stenosis 40–69% and mild <40% lumen diameter reduction. A reference standard invasive coronary angiography was done according to conventional technique through standard trans-femoral approach and was evaluated by an observer blinded to the MSCT results. Results: The diagnostic accuracy of MSCT for the detection or exclusion of significant stenosis in grafts body and their anastomotic sites was 99.28%, sensitivity, specificity, positive and negative predictive values were 97.75%, 100%, 100%, 98.95%. The diagnostic accuracy for detection of degree of graft stenosis (mild, moderate, severe or occluded) was 97.18%. Conclusion: Noninvasive MSCT angiography is an excellent tool for evaluating patency or degree of stenosis of bypass grafts body and their anastomotic sites in post-CABG patients

    PARP is activated in human asthma and its inhibition by olaparib blocks house dust mite-induced disease in mice

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    Our laboratory established a role for poly(ADP-ribose)polymerase (PARP) in asthma. To increase the clinical significance of our studies, it is imperative to demonstrate that PARP is actually activated in human asthma, to examine whether a PARP inhibitor approved for human testing such as olaparib blocks already-established chronic asthma traits in response to house dust mite (HDM), a true human allergen, in mice and to examine whether the drug modulates human cluster of differentiation type 4 (CD4(+)) T-cell function. To conduct the study, human lung specimens and peripheral blood mononuclear cells (PBMCs) and a HDM-based mouse asthma model were used. Our results show that PARP is activated in PBMCs and lung tissues of asthmatics. PARP inhibition by olaparib or gene knockout blocked established asthma-like traits in mice chronically exposed to HDM including airway eosinophilia and hyper-responsiveness. These effects were linked to a marked reduction in T helper 2 (Th2) cytokine production without a prominent effect on interferon (IFN)-\u3b3 or interleukin (IL)-10. PARP inhibition prevented HDM-induced increase in overall cellularity, weight and CD4(+) T-cell population in spleens of treated mice whereas it increased the T-regulatory cell population. In CD3/CD28-stimulated human CD4 (+)T-cells, olaparib treatment reduced Th2 cytokine production potentially by modulating GATA binding protein-3 (gata-3)/IL-4 expression while moderately affecting T-cell proliferation. PARP inhibition inconsistently increased IL-17 in HDM-exposed mice and CD3/CD28-stimulated CD4(+) T cells without a concomitant increase in factors that can be influenced by IL-17. In the present study, we provide evidence for the first time that PARP-1 is activated in human asthma and that its inhibition is effective in blocking established asthma in mice

    Impact of COVID-19 on Cardiovascular Testing in the United States Versus the Rest of the World

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    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-U.S. institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p &lt; 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection
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