Evaluation of the in vivo role of vaccinia virus complement control protein (VCP) following renal ischemia

Includes bibliographical references (leaves 133-147)In transplantation, vascularized organs often suffer the consequences of ischemic damage as well as reperfusion injury following the reestablishment of blood flow. The induced ischemialreperfusion (I/R) damage is usually associated with the accumulation of injurious complement components. The vaccinia virus complement control protein (VCP) has the ability to simultaneously inhibit the classical and the alternative complement pathways by binding to the early components C3b and C4b. The complement component C3 is known to be the central route to all of the known complement activation pathways. As a result, it is involved in a number of complement-mediated ailments including renal ischemia/reperfusion injury. The objectives of this study were to initially evaluate the in vitro roles of the natural VCP and the humanized recombinant VCP (hrVCP), and then to establish their in vivo roles in a renal I/R injury model

Pleiotropic effect of the proton pump inhibitor esomeprazole leading to suppression of lung inflammation and fibrosis

Background: The beneficial outcome associated with the use of proton pump inhibitors (PPIs) in idiopathic pulmonary fibrosis (IPF) has been reported in retrospective studies. To date, no prospective study has been conducted to confirm these outcomes. In addition, the potential mechanism by which PPIs improve measures of lung function and/or transplant-free survival in IPF has not been elucidated. Methods: Here, we used biochemical, cell biological and preclinical studies to evaluate regulation of markers associated with inflammation and fibrosis. In our in vitro studies, we exposed primary lung fibroblasts, epithelial and endothelial cells to ionizing radiation or bleomycin; stimuli typically used to induce inflammation and fibrosis. In addition, we cultured lung fibroblasts from IPF patients and studied the effect of esomeprazole on collagen release. Our preclinical study tested efficacy of esomeprazole in a rat model of bleomycin-induced lung injury. Furthermore, we performed retrospective analysis of interstitial lung disease (ILD) databases to examine the effect of PPIs on transplant-free survival. Results: The cell culture studies revealed that esomeprazole controls inflammation by suppressing the expression of pro-inflammatory molecules including vascular cell adhesion molecule-1, inducible nitric oxide synthase, tumor necrosis factor-alpha (TNF-alpha) and interleukins (IL-1 beta and IL-6). The antioxidant effect is associated with strong induction of the stress-inducible cytoprotective protein heme oxygenase-1 (HO1) and the antifibrotic effect is associated with potent inhibition of fibroblast proliferation as well as downregulation of profibrotic proteins including receptors for transforming growth factor beta (TGF beta), fibronectin and matrix metalloproteinases (MMPs). Furthermore, esomeprazole showed robust effect in mitigating the inflammatory and fibrotic responses in a murine model of acute lung injury. Finally, retrospective analysis of two ILD databases was performed to assess the effect of PPIs on transplant-free survival in IPF patients. Intriguingly, this data demonstrated that IPF patients on PPIs had prolonged survival over controls (median survival of 3.4 vs 2 years). Conclusions: Overall, these data indicate the possibility that PPIs may have protective function in IPF by directly modulating the disease process and suggest that they may have other clinical utility in the treatment of extra-intestinal diseases characterized by inflammatory and/or fibrotic phases.Stanford School of Medicine [1049528-149- KAVFB]; Tobacco-Related Disease Research Program of the University of California [20FT-0090]; National Institutes of Health National Heart, Lung, and Blood Institute [5K01HL118683, P01HL114470]; Houston Methodist Research Institute [25150001]; Stanford SPARK Translational Research ProgramSCI(E)[email protected]

Modulating DDAH/NOS Pathway to Discover Vasoprotective Insulin Sensitizers

Insulin resistance syndrome (IRS) is a configuration of cardiovascular risk factors involved in the development of metabolic disorders including type 2 diabetes mellitus. In addition to diet, age, socioeconomic, and environmental factors, genetic factors that impair insulin signaling are centrally involved in the development and exacerbation of IRS. Genetic and pharmacological studies have demonstrated that the nitric oxide (NO) synthase (NOS) genes are critically involved in the regulation of insulin-mediated glucose disposal. The generation of NO by the NOS enzymes is known to contribute to vascular homeostasis including insulinmediated skeletal muscle vasodilation and insulin sensitivity. By contrast, excessive inhibition of NOS enzymes by exogenous or endogenous factors is associated with insulin resistance (IR). Asymmetric dimethylarginine (ADMA) is an endogenous molecule that competitively inhibits all the NOS enzymes and contributes to metabolic perturbations including IR. The concentration of ADMA in plasma and tissue is enzymatically regulated by dimethylarginine dimethylaminohydrolase (DDAH), a widely expressed enzyme in the cardiovascular system. In preclinical studies, overexpression of DDAH has been shown to reduce ADMA levels, improve vascular compliance, and increase insulin sensitivity. This review discusses the feasibility of the NOS/DDAH pathway as a novel target to develop vasoprotective insulin sensitizers

Dietary nitrate, nitric oxide, and restenosis

Endothelium-derived NO controls the contractility and growth state of the underlying vascular smooth muscle cells and regulates the interaction of the vessel wall with circulating blood elements. Acute injury of the vessel wall denudes the endothelial lining, removing homeostatic regulation and precipitating a wave of events leading to myointimal hyperplasia. In this issue of the JCI, Alef and colleagues provide evidence that in the injured vessel wall, the disruption of the NOS pathway is countered by induction of xanthine oxidoreductase, an enzyme capable of producing NO from nitrite. In addition, they link low dietary nitrite levels to increased severity of myointimal hyperplasia following vessel injury in mice

Pharmacovigilance using Clinical Text

Abstract. The current state of the art in post-marketing drug surveillance utilizes voluntarily submitted reports of suspected adverse drug reactions. We present data mining methods that transform unstructured patient notes taken by doctors, nurses and other clinicians into a de-identified, temporally ordered, patient-feature matrix using standardized medical terminologies. We demonstrate how to use the resulting high-throughput data to monitor for adverse drug events based on the clinical notes in the EHR. Introduction. We show that it is possible to investigate adverse drug event associations with high accuracy (46% sensitivity, 91 % specificity) by analyzing textual notes in a clinical data warehouse using automated methods. We examine suspected associations for confounding via stratification and propensity score matching. We find that such an analysis of textual clinical notes could detect adverse drug events 2 years before the official alert. Using this approach we find that proton pump inhibitors (PPIs) as a class appear strongly associated with major advers

Limited gene expression variation in human embryonic stem cell and induced pluripotent stem cell-derived endothelial cells.

Recent evidence suggests human embryonic stem cell (hESC) and induced pluripotent stem (iPS) cell lines have differences in their epigenetic marks and transcriptomes, yet the impact of these differences on subsequent terminally differentiated cells is less well understood. Comparison of purified, homogeneous populations of somatic cells derived from multiple independent human iPS and ES lines will be required to address this critical question. Here, we report a differentiation protocol based on embryonic development that consistently yields large numbers of endothelial cells (ECs) derived from multiple hESCs or iPS cells. Mesoderm differentiation of embryoid bodies was maximized, and defined growth factors were used to generate KDR(+) EC progenitors. Magnetic purification of a KDR(+) progenitor subpopulation resulted in an expanding, homogeneous pool of ECs that expressed EC markers and had functional properties of ECs. Comparison of the transcriptomes revealed limited gene expression variability between multiple lines of human iPS-derived ECs or between lines of ES- and iPS-derived ECs. These results demonstrate a method to generate large numbers of pure human EC progenitors and differentiated ECs from pluripotent stem cells and suggest individual lineages derived from human iPS cells may have significantly less variance than their pluripotent founders