Drug Safety science

Beerse, Belgium

Drug Safety science

Beerse, Belgium
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Dragomir A.,Rutgers University | Sun R.,Rutgers University | Mishin V.,Rutgers University | Hall L.B.,Drug Safety science | And 2 more authors.
Toxicological Sciences | Year: 2012

Galectin-3 (Gal-3) is a β-galactoside-binding lectin implicated in the regulation of macrophage activation and inflammatory mediator production. In the present studies, we analyzed the role of Gal-3 in liver inflammation and injury induced by acetaminophen (APAP). Treatment of wild-type (WT) mice with APAP (300 mg/kg, ip) resulted in centrilobular hepatic necrosis and increases in serum transaminases. This was associated with increased hepatic expression of Gal-3 messenger RNA and protein. Immunohistochemical analysis showed that Gal-3 was predominantly expressed by mononuclear cells infiltrating into necrotic areas. APAP-induced hepatotoxicity was reduced in Gal-3-deficient mice. This was most pronounced at 48-72 h post-APAP and correlated with decreases in APAP-induced expression of 24p3, a marker of inflammation and oxidative stress. These effects were not due to alterations in APAP metabolism or hepatic glutathione levels. The proinflammatory proteins, inducible nitric oxide synthase (iNOS), interleukin (IL)-1β, macrophage inflammatory protein (MIP)-2, matrix metalloproteinase (MMP)-9, and MIP-3α, as well as the Gal-3 receptor (CD98), were upregulated in livers of WT mice after APAP intoxication. Loss of Gal-3 resulted in a significant reduction in expression of iNOS, MMP-9, MIP-3α, and CD98, with no effects on IL-1β. Whereas APAP-induced increases in MIP-2 were augmented at 6 h in Gal-3. -/- mice when compared with WT mice, at 48 and 72 h, they were suppressed. Tumor necrosis factor receptor-1 (TNFR1) was also upregulated after APAP, a response dependent on Gal-3. Moreover, exaggerated APAP hepatotoxicity in mice lacking TNFR1 was associated with increased Gal-3 expression. These data demonstrate that Gal-3 is important in promoting inflammation and injury in the liver following APAP intoxication. © The Author 2012. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved.

Authier S.,CIToxLAB North America | Vargas H.M.,Amgen | Curtis M.J.,St Thomas Hospital | Holbrook M.,Covance | Pugsley M.K.,Drug Safety science
Journal of Pharmacological and Toxicological Methods | Year: 2013

Introduction: The Safety Pharmacology (SP) Society (SPS) conducted an industry survey in 2012 in an attempt to define current industry practices as they relate to inclusion of safety pharmacology (SP) endpoints into Toxicology studies. Methods: A total of 361 participants from Asia (9.1%), Europe (19.4%) and North America (71.4%) responded to the survey. The preponderance of respondents were toxicologists (53.2%) followed by safety pharmacologists (27.2%) and scientists involved in the conduct of both disciplines (19.6%). Most participants (58.6%) were from pharmaceutical companies employing more than 500 employees. Results: A majority (68.2%) reported having experience in designing, performing or interpreting the SP component of a study when performed as part of a toxicology study. Some participants (42.0%) had submitted data to a regulatory agency where ICHS7 studies were performed as part of a toxicology study rather than as a standalone study. When comparing species that were used in studies in which SP was added to toxicology studies, canines were the most frequently reported animals used for new chemical entities (NCE) whereas non-human (NH) primates were the most frequent for the assessment of biological agents. The most frequent primary motivator for adding ICHS7 SP endpoints to regulatory toxicology studies was to generate additional data to allow for determination of an integrated risk assessment thereby testing Confidence in Safety (CIS) to better manage and/or mitigate risk. The current ability to add safety pharmacology endpoints into regulatory toxicology studies was used to address a specific concern (by 42.1% of respondents) to allow management of risk more effectively (36.8%) or to generate data that contributes to cessation of the progression of a compound (21.1%). For an NCE, SP measurements in toxicology studies were conducted in addition to standalone SP studies (by 40.6% of respondents) or in addition/instead of standalone safety pharmacology studies (by 39.8% of respondents). For biological agents, a majority (74.3%) indicated SP measurements in toxicology were conducted instead of standalone studies as outlined in the ICHS6 guideline while inclusion of SP endpoints in toxicology studies for biological agents in addition to standalone studies was reported by only 25.7% of the respondents. Discussion: The survey highlights that obtaining regulatory agreement for the proposed combined SP/Tox study designs may be useful before study conduct in some cases. Respondents suggest that such discussion could occur at the pre-IND meeting before the IND/CTA enabling program. © 2013 Elsevier Inc.

Malaviya R.,Rutgers University | Venosa A.,Rutgers University | Hall L.,Drug Safety science | Gow A.J.,Rutgers University | And 3 more authors.
Toxicology and Applied Pharmacology | Year: 2012

Nitrogen mustard (NM) is a toxic vesicant known to cause damage to the respiratory tract. Injury is associated with increased expression of inducible nitric oxide synthase (iNOS). In these studies we analyzed the effects of transient inhibition of iNOS using aminoguanidine (AG) on NM-induced pulmonary toxicity. Rats were treated intratracheally with 0.125mg/kg NM or control. Bronchoalveolar lavage fluid (BAL) and lung tissue were collected 1d-28d later and lung injury, oxidative stress and fibrosis assessed. NM exposure resulted in progressive histopathological changes in the lung including multifocal lesions, perivascular and peribronchial edema, inflammatory cell accumulation, alveolar fibrin deposition, bronchiolization of alveolar septal walls, and fibrosis. This was correlated with trichrome staining and expression of proliferating cell nuclear antigen (PCNA). Expression of heme oxygenase (HO)-1 and manganese superoxide dismutase (Mn-SOD) was also increased in the lung following NM exposure, along with levels of protein and inflammatory cells in BAL, consistent with oxidative stress and alveolar-epithelial injury. Both classically activated proinflammatory (iNOS+ and cyclooxygenase-2+) and alternatively activated profibrotic (YM-1+ and galectin-3+) macrophages appeared in the lung following NM administration; this was evident within 1d, and persisted for 28d. AG administration (50mg/kg, 2×/day, 1d-3d) abrogated NM-induced injury, oxidative stress and inflammation at 1d and 3d post exposure, with no effects at 7d or 28d. These findings indicate that nitric oxide generated via iNOS contributes to acute NM-induced lung toxicity, however, transient inhibition of iNOS is not sufficient to protect against pulmonary fibrosis. © 2012 Elsevier Inc.

Raghavan N.,Biostatistics | Nie A.Y.,Foley and Larder LLP | McMillian M.,Drug Safety science | Amaratunga D.,Johnson Research and Development Co., Inc.
Statistics in Biopharmaceutical Research | Year: 2012

This article presents a novel approach for developing a linear prediction rule to predict the non-genotoxic carcinogenicity potential of a new compound in the drug development pipeline. We construct the approach using data from 24-hour microarray experiments on rats treated with the compound. This method was developed to address an actual problem that we were presented with by scientists in mechanistic toxicology. Short-term, preclinical assays for non-genotoxic carcinogenicity, a toxicity commonly observed in long-term rodent carcinogenicity studies, have proven difficult to develop. A quick and early preclinical assay, such as this, is of particular interest and urgency. The linear prediction rule is derived using an Ensemble Linear Discriminant classifier. This is a hybrid approach which leverages the advantages of ensemble approaches for addressing over-fitting (a problem endemic to microarray data), and that of LDA for interpretability. In a limited comparison with some other classifiers, including random forest, we show that our approach has good predictive performance in addition to being interpretable. © 2012 Copyright Taylor and Francis Group, LLC.

Van den Bulck K.,Drug Safety science | Hill A.,Evotec | Mesens N.,Drug Safety science | Diekman H.,Evotec | And 2 more authors.
Reproductive Toxicology | Year: 2011

The zebrafish embryotoxicity/teratogenicity assay is described as a useful alternative screening model to evaluate the effect of drugs on embryofoetal development. Fertilized eggs were exposed to different concentrations of 15 compounds with teratogenic (8) and non-teratogenic (7) potential until 96. h post-fertilization when 28 morphological endpoints and the level of compound uptake was assessed. The majority of drugs testing positive in mammals was also positive in zebrafish (75% sensitivity), while a relative high number of false positives were noted (43% specificity). Compound uptake determination appears useful for clarifying classifications as teratogenic or potential overdose although assay sensitivity could be improved to 71% if the exposure threshold, previously suggested as ∼50. ng/larvae, is reconsidered. The zebrafish assay shows some potential, though limited in its current form, as a screening tool for developmental toxicity within Janssen drug development. Further assay refinement with respect to endpoints and body burden threshold is required. © 2011 Elsevier Inc.

Sunil V.R.,Rutgers University | Vayas K.N.,Rutgers University | Cervelli J.A.,Rutgers University | Malaviya R.,Rutgers University | And 5 more authors.
Experimental and Molecular Pathology | Year: 2014

Nitrogen mustard (NM) is a toxic alkylating agent that causes damage to the respiratory tract. Evidence suggests that macrophages and inflammatory mediators including tumor necrosis factor (TNF)α contribute to pulmonary injury. Pentoxifylline is a TNFα inhibitor known to suppress inflammation. In these studies, we analyzed the ability of pentoxifylline to mitigate NM-induced lung injury and inflammation. Exposure of male Wistar rats (150-174g; 8-10weeks) to NM (0.125mg/kg, i.t.) resulted in severe histopathological changes in the lung within 3d of exposure, along with increases in bronchoalveolar lavage (BAL) cell number and protein, indicating inflammation and alveolar-epithelial barrier dysfunction. This was associated with increases in oxidative stress proteins including lipocalin (Lcn)2 and heme oxygenase (HO)-1 in the lung, along with pro-inflammatory/cytotoxic (COX-2+ and MMP-9+), and anti-inflammatory/wound repair (CD163+ and Gal-3+) macrophages. Treatment of rats with pentoxifylline (46.7mg/kg, i.p.) daily for 3d beginning 15min after NM significantly reduced NM-induced lung injury, inflammation, and oxidative stress, as measured histologically and by decreases in BAL cell and protein content, and levels of HO-1 and Lcn2. Macrophages expressing COX-2 and MMP-9 also decreased after pentoxifylline, while CD163+ and Gal-3+ macrophages increased. This was correlated with persistent upregulation of markers of wound repair including pro-surfactant protein-C and proliferating nuclear cell antigen by Type II cells. NM-induced lung injury and inflammation were associated with alterations in the elastic properties of the lung, however these were largely unaltered by pentoxifylline. These data suggest that pentoxifylline may be useful in treating acute lung injury, inflammation and oxidative stress induced by vesicants. © 2014 Elsevier Inc.

Meermann B.,Ghent University | Bockx M.,Drug Safety science | Laenen A.,Drug Safety science | Van Looveren C.,Drug Safety science | And 2 more authors.
Analytical and Bioanalytical Chemistry | Year: 2012

The aim of this work was speciation analysis of metabolites in feces samples collected within a clinical study during which a bromine-containing anti-tuberculosis drug (TMC207) was administered to patients with multi-drug resistant tuberculosis infection. Owing to slow elimination of the drug, no 14C label was used within this study. Quantification of the bromine species was accomplished using high performance liquid chromatography coupled to inductively coupled plasma-mass spectrometry (HPLC/ICP-MS) in combination with on-line isotope dilution (on-line ID), while structural elucidation of the species was performed using HPLC coupled to electrospray ionization-mass spectrometry. The ICP-MS-based method developed shows a good intra- and inter-day reproducibility (relative standard deviation∈=∈3.5%, N∈=∈9); the limit of detection (1.5 mg TMC207 L -1) is of the same order of magnitude as that for HPLC/radiodetection; the dynamic range of the method covers more than two orders of magnitude. Furthermore, the column recovery was demonstrated to be quantitative (recoveries between 90.6% and 99.5%). Based on the excellent figures of merit, the "cold" HPLC/ICP-MS approach could be deployed for the actual human in vivo metabolism study, such that exposure of the human volunteers to the 14C radiolabel was avoided. [Figure not available: see fulltext.] © 2011 Springer-Verlag.

Meermann B.,Ghent University | Hulstaert A.,Ghent University | Laenen A.,Drug Safety science | Looveren C.V.,Drug Safety science | And 3 more authors.
Analytical Chemistry | Year: 2012

During the development of a new drug compound, its metabolism needs to be unraveled. For quantification of the metabolites formed, the drug under investigation is traditionally synthesized with a radiolabel ( 14C or 3H) and the metabolites present in different matrixes (blood, urine, feces) upon drug administration are determined by means of high-performance liquid chromatography (HPLC) coupled to radiodetection. This approach allows for quantification of the metabolites formed and enables a straightforward distinction between exogenous (i.e., drug-related) and endogenous species (as only the radiolabeled species are detected). However, in some cases, the use of a radiolabeled compound in human in vivo studies is not advisible, e.g., for drug compounds or their metabolites showing a long plasma or tissue half-life. In cases where the candidate drug molecule contains an element detectable by means of inductively coupled plasma mass spectrometry (ICP-MS), HPLC/ICP-MS is a promising alternative approach. However, the method lacks specificity when a distinction between drug-related species and endogenous compounds containing the same target element needs to be accomplished. As a result, we have developed an HPLC/ICP-MS-based method combined with "reverse" online isotope dilution ("reverse" online ID) for metabolite quantification. The methodology was evaluated by the analysis of feces samples from rats dosed with a 81Br-labeled drug compound. The method allows for both (i) valid quantification of the drug metabolites and (ii) distinction among endogenous, exogenous, and "mixed" species, based on their isotopic "fingerprint". A good repeatability (relative standard deviation of 4.2%) and limit of detection (0.35 mg of drug compound L -1 of feces extract), of the same order of magnitude as those observed for "normal" online ID HPLC/ICP-MS and HPLC/radiodetection, were achieved. © 2012 American Chemical Society.

Groves A.M.,Rutgers University | Gow A.J.,Rutgers University | Massa C.B.,Rutgers University | Hall L.,Drug Safety science | And 2 more authors.
American Journal of Physiology - Lung Cellular and Molecular Physiology | Year: 2013

In these studies we determined whether progressive pulmonary inflammation associated with aging in surfactant protein D (Sftpd)-/- mice leads to an exacerbated response to ozone. In Sftpd^/^ mice, but not wild-type (WT) mice, age-related increases in numbers of enlarged vacuolated macrophages were observed in the lung, along with alveolar wall rupture, type 2 cell hyperplasia, and increased bronchoalveolar lavage protein and cell content. Numbers of heme oxygenase + macrophages also increased with age in Sftpd-/- mice, together with classically (iNOS +) and alternatively (mannosereceptor+, YM-1 +, orgalectin-3 +) activated macrophages. In both WT and Sftpd-/- mice, increasing age from 8 to 27 wk was associated with reduced lung stiffness, as reflected by decreases in resistance and elastance spectra; however, this response was reversed in 80-wk-old Sftpd-/- mice. Ozone exposure (0.8 ppm, 3 h) caused increases in lung pathology, alveolar epithelial barrier dysfunction, and numbers of iNOS+ macrophages in 8- and 27-wk-old Sftpd-/-, but not WT mice at 72 h postexposure. Conversely, increases in alternatively activated macrophages were observed in 8-wk-old WT mice following ozone exposure, but not in Sftpd-/- mice. Ozone also caused alterations in both airway and tissue mechanics in Sftpd-/- mice at 8 and 27 wk, but not at 80 wk. These data demonstrate that mild to moderate pulmonary inflammation results in increased sensitivity to ozone; however, in senescent mice, these responses are overwhelmed by the larger effects of age-related increases in baseline inflammation and lung injury. © 2013 the American Physiological Society.

Cuyckens F.,Drug Safety science | Pauwels N.,Drug Safety science | Koppen V.,Drug Safety science | Leclercq L.,Drug Safety science
Bioanalysis | Year: 2012

Background: There is considerable interest in the determination of relative abundances of human metabolites in plasma (and potentially excreta) with reasonable accuracy early on in the drug development process in order to make scientifically sound decisions with regard to the presence of potentially active or toxic disproportionate metabolites. At this point, authentic metabolite standards are generally not available. Results: A new methodology is proposed for the estimation of metabolite concentrations in the absence of authentic standards. A reference sample containing radiolabeled metabolites of interest is produced by incubating the 14C-labeled drug in vitro, and mixed with a sample to be quantitated containing the unlabeled metabolites. The 12C/ 14C isotope ratio is measured with high-resolution ESI-MS for each metabolite, and used as a basis for quantitation of the cold metabolite based on the concentration of radioactive metabolite, determined from independent analysis of the radioactive sample with LC-radiochemical detection. The 14C-labeled metabolite serves as an isotopically labeled internal standard, which corrects for any variations in injection volume, sample preparation, MS intensity drift, matrix effects and/or saturation of electrospray ionization. The approach was validated by the analysis of solutions containing variable amounts of the analyte with a fixed amount of radioactive standard on a QToF Synapt ® G2 MS system. The same methodology was also successfully applied to first-in-human plasma samples analyzed on a LTQ-Orbitrap ®. Conclusion: The metabolite abundances obtained by 12C/ 14C isotope ratio measurements showed suitable accuracy and precision and were very close to those obtained with matrix mixing. The parent drug concentrations also corresponded well with the bioanalytical results obtained with a validated LC-MS/MS method. © 2012 Future Science Ltd.

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