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Latham LE, Dobrovolsky VN, Liu S, Talpos JC, Hanig JP, Slikker W, Wang C, Liu F. Establishment of neural stem cells from fetal monkey brain for neurotoxicity testing. Exp Biol Med (Maywood) 2023; 248:633-640. [PMID: 37208932 PMCID: PMC10350806 DOI: 10.1177/15353702231168145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 03/06/2023] [Indexed: 05/21/2023] Open
Abstract
Neurotoxicity assessments are generally performed using laboratory animals. However, as in vitro neurotoxicity models are continuously refined to reach adequate predicative concordance with in vivo responses, they are increasingly used for some endpoints of neurotoxicity. In this study, gestational day 80 fetal rhesus monkey brain tissue was obtained for neural stem cells (NSCs) isolation. Cells from the entire hippocampus were harvested, mechanically dissociated, and cultured for proliferation and differentiation. Immunocytochemical staining and biological assays demonstrated that the harvested hippocampal cells exhibited typical NSC phenotypes in vitro: (1) cells proliferated vigorously and expressed NSC markers nestin and sex-determining region Y-box 2 (SOX2) and (2) cells differentiated into neurons, astrocytes, and oligodendrocytes, as confirmed by positive staining with class III β-tubulin, glial fibrillary acidic protein, and galactocerebroside, respectively. The NSC produced detectable responses following neurotoxicant exposures (e.g. trimethyltin and 3-nitropropionic acid). Our results indicated that non-human primate NSCs may be a practical tool to study the biology of neural cells and to evaluate the neurotoxicity of chemicals in vitro, thereby providing data that are translatable to humans and may also reduce the number of animals needed for developmental neurotoxicological studies.
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Affiliation(s)
- Leah E Latham
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. FDA, Jefferson, AR 72079, USA
| | - Vasily N Dobrovolsky
- Division of Genetic and Molecular Toxicology, National Center for Toxicological Research, U.S. FDA, Jefferson, AR 72079, USA
| | - Shuliang Liu
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. FDA, Jefferson, AR 72079, USA
| | - John C Talpos
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. FDA, Jefferson, AR 72079, USA
| | - Joseph P Hanig
- Office of Pharmaceutical Quality, Center for Drug Evaluation and Research, U.S. FDA, Silver Spring, MD 20903, USA
| | - William Slikker
- Office of Director, National Center for Toxicological Research, U.S. FDA, Jefferson, AR 72079, USA
| | - Cheng Wang
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. FDA, Jefferson, AR 72079, USA
| | - Fang Liu
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. FDA, Jefferson, AR 72079, USA
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Liachenko SM, Sadovova NV, Tripp A, Ghorai S, Patri AK, Hanig JP, Cohen JE, Krefting I. Optimization of Detection of Gadodiamide Brain Retention in Rats Using Quantitative T 2 Mapping and Intraperitoneal Administration. J Magn Reson Imaging 2022; 56:1499-1504. [PMID: 35278003 DOI: 10.1002/jmri.28149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 02/24/2022] [Accepted: 02/25/2022] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Currently, the gadolinium retention in the brain after the use of contrast agents is studied by T1 -weighted magnetic resonance imaging (MRI) (T1 w) and T1 mapping. The former does not provide easily quantifiable data and the latter requires prolonged scanning and is sensitive to motion. T2 mapping may provide an alternative approach. Animal studies of gadolinium retention are complicated by repeated intravenous (IV) dosing, whereas intraperitoneal (IP) injections might be sufficient. HYPOTHESIS T2 mapping will detect the changes in the rat brain due to gadolinium retention, and IP administration is equivalent to IV for long-term studies. STUDY TYPE Prospective longitudinal. ANIMAL MODEL A total of 31 Sprague-Dawley rats administered gadodiamide IV (N = 8) or IP (N = 8), or saline IV (N = 6) or IP (N = 9) 4 days per week for 5 weeks. FIELD STRENGTH/SEQUENCES A 7 T, T1 w, and T2 mapping. ASSESSMENT T2 relaxation and image intensities in the deep cerebellar nuclei were measured pre-treatment and weekly for 5 weeks. Then brains were assessed for neuropathology (N = 4) or gadolinium content using inductively coupled plasma mass spectrometry (ICP-MS, N = 12). STATISTICAL TESTS Repeated measures analysis of variance with post hoc Student-Newman-Keuls tests and Hedges' effect size. RESULTS Gadolinium was detected by both approaches; however, T2 mapping was more sensitive (effect size 2.32 for T2 vs. 0.95 for T1 w), and earlier detection (week 3 for T2 vs. week 4 for T1 w). ICP-MS confirmed the presence of gadolinium (3.076 ± 0.909 nmol/g in the IV group and 3.948 ± 0.806 nmol/g in the IP group). There was no significant difference between IP and IV groups (ICP-MS, P = 0.109; MRI, P = 0.696). No histopathological abnormalities were detected in any studied animal. CONCLUSION T2 relaxometry detects gadolinium retention in the rat brain after multiple doses of gadodiamide irrespective of the route of administration. EVIDENCE LEVEL 1 TECHNICAL EFFICACY: Stage 1.
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Affiliation(s)
- Serguei M Liachenko
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas, USA
| | - Natalya V Sadovova
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas, USA
| | - Arnold Tripp
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas, USA
| | - Suman Ghorai
- Nanotechnology Core Facility, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas, USA
| | - Anil K Patri
- Nanotechnology Core Facility, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas, USA
| | - Joseph P Hanig
- Office of Pharmaceutical Quality, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, White Oak, Maryland, USA
| | - Jonathan E Cohen
- Office of New Drugs, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, White Oak, Maryland, USA
| | - Ira Krefting
- Office of New Drugs, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, White Oak, Maryland, USA
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Srivastava A, Liachenko S, Sarkar S, Paule M, Sadovova N, Hanig JP. Global Neurotoxicity: Quantitative Analysis of Rat Brain Toxicity Following Exposure to Trimethyltin. Int J Toxicol 2021; 40:367-379. [PMID: 33878910 DOI: 10.1177/10915818211009193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The organotin, trimethyltin (TMT), is a highly toxic compound. In this study, silver-stained rat brain sections were qualitatively and quantitatively evaluated for degeneration after systemic treatment with TMT. Degenerated neurons were counted using image analysis methods available in the HALO image analysis software. Specific brain areas including the cortex, inferior and superior colliculus, and thalamus were quantitatively analyzed. Our results indicate extensive and widespread damage to the rat brain after systemic administration of TMT. Qualitative results suggest severe TMT-induced toxicity 3 and 7 days after the administration of TMT. Trimethyltin toxicity was greatest in the hippocampus, olfactory area, cerebellum, pons, mammillary nucleus, inferior and superior colliculus, hypoglossal nucleus, thalamus, and cerebellar Purkinje cells. Quantification showed that the optic layer of the superior colliculus exhibited significantly more degeneration compared to layers above and below. The inferior colliculus showed greater degeneration in the dorsal area relative to the central area. Similarly, in cortical layers, there was greater neurodegeneration in deeper layers compared to superficial layers. Quantification of damage in various thalamic nuclei showed that the greatest degeneration occurred in midline and intralaminar nuclei. These results suggest selective neuronal network vulnerability to TMT-related toxicity in the rat brain.
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Affiliation(s)
- Anshul Srivastava
- 4137U.S. Food and Drug Administration, Center for Drug Evaluation and Research (CDER/OPQ), Silver Spring, MD, USA
| | - Serguei Liachenko
- 4137U.S. Food and Drug Administration, National Center for Toxicological Research (NCTR/DNT), Jefferson, AR, USA
| | - Sumit Sarkar
- 4137U.S. Food and Drug Administration, National Center for Toxicological Research (NCTR/DNT), Jefferson, AR, USA
| | - Merle Paule
- 4137U.S. Food and Drug Administration, National Center for Toxicological Research (NCTR/DNT), Jefferson, AR, USA
| | - Natalya Sadovova
- 4137U.S. Food and Drug Administration, National Center for Toxicological Research (NCTR/DNT), Jefferson, AR, USA
| | - Joseph P Hanig
- 4137U.S. Food and Drug Administration, Center for Drug Evaluation and Research (CDER/OPQ), Silver Spring, MD, USA
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Srivastava A, Hanig JP. Quantitative neurotoxicology: Potential role of artificial intelligence/deep learning approach. J Appl Toxicol 2020; 41:996-1006. [PMID: 33140470 DOI: 10.1002/jat.4098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 10/17/2020] [Indexed: 12/17/2022]
Abstract
Neurotoxicity studies are important in the preclinical stages of drug development process, because exposure to certain compounds that may enter the brain across a permeable blood brain barrier damages neurons and other supporting cells such as astrocytes. This could, in turn, lead to various neurological disorders such as Parkinson's or Huntington's disease as well as various dementias. Toxicity assessment is often done by pathologists after these exposures by qualitatively or semiquantitatively grading the severity of neurotoxicity in histopathology slides. Quantification of the extent of neurotoxicity supports qualitative histopathological analysis and provides a better understanding of the global extent of brain damage. Stereological techniques such as the utilization of an optical fractionator provide an unbiased quantification of the neuronal damage; however, the process is time-consuming. Advent of whole slide imaging (WSI) introduced digital image analysis which made quantification of neurotoxicity automated, faster and with reduced bias, making statistical comparisons possible. Although automated to a certain level, simple digital image analysis requires manual efforts of experts which is time-consuming and limits analysis of large datasets. Digital image analysis coupled with a deep learning artificial intelligence model provides a good alternative solution to time-consuming stereological and simple digital analysis. Deep learning models could be trained to identify damaged or dead neurons in an automated fashion. This review has focused on and discusses studies demonstrating the role of deep learning in segmentation of brain regions, toxicity detection and quantification of degenerated neurons as well as the estimation of area/volume of degeneration.
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Affiliation(s)
- Anshul Srivastava
- Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland, USA
| | - Joseph P Hanig
- Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland, USA
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Liu F, Gong B, Gu Q, Liu S, Fogle CM, Patterson TA, Hanig JP, Slikker W, Wang C. Application of microRNA profiling to understand sevoflurane-induced adverse effects on developing monkey brain. Neurotoxicology 2020; 81:172-179. [PMID: 33045284 DOI: 10.1016/j.neuro.2020.10.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 10/06/2020] [Accepted: 10/06/2020] [Indexed: 02/06/2023]
Abstract
We have described that prolonged sevoflurane exposure at a clinically-relevant concentration of 2.5 % caused neuronal cell death in the developing monkey brain. Postnatal day 5 or 6 rhesus monkeys (n = 3) were exposed to 2.5 % sevoflurane for 8 h. Monkeys kept at environmental conditions in the procedure room served as controls (n = 3). Brain tissues were harvested four hours after sevoflurane exposure for histological analysis, and RNA or protein extraction. MicroRNA (miRNA) profiling on the frontal cortex of monkey brains was performed using next-generation sequencing. 417 miRNAs were identified in the frontal cortex, where most neuronal cell death was observed. 7 miRNAs were differentially expressed in frontal cortex after sevoflurane exposure. Five of these were expressed at significantly lower levels than controls and the other two miRNAs were expressed significantly higher. These differentially expressed miRNAs (DEMs) were then loaded to the Ingenuity Pathway Analysis database for pathway analysis, in which targeting information was available for 5 DEMs. The 5 DEMs target 2,919 mRNAs which are involved in pathways that contribute to various cellular functions. Of note, 78 genes that are related to axon guidance signaling were targeted, suggesting that development of the neural circuit may be affected after sevoflurane exposure. Such changes may have long-term effects on brain development and function. These findings are supplementary to our previous observations and provide more evidence for better understanding the adverse effects of sevoflurane on the developing brain after an 8 -h exposure.
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Affiliation(s)
- Fang Liu
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR, United States.
| | - Binsheng Gong
- Division of Bioinformatics and Biostatistics, National Center for Toxicological Research/FDA, Jefferson, AR, United States
| | - Qiang Gu
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR, United States
| | - Shuliang Liu
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR, United States
| | - Charles Matthew Fogle
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR, United States
| | - Tucker A Patterson
- Office of Director, National Center for Toxicological Research/FDA, Jefferson, AR, United States
| | - Joseph P Hanig
- Office of Pharmaceutical Quality, Center for Drug Evaluation and Research/FDA, Silver Spring, MD, United States
| | - William Slikker
- Office of Director, National Center for Toxicological Research/FDA, Jefferson, AR, United States
| | - Cheng Wang
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR, United States.
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Srivastava A, Liachenko S, Sarkar S, Paule M, Negi G, Pandey JP, Hanig JP. Quantitative Neurotoxicology: An Assessment of the Neurotoxic Profile of Kainic Acid in Sprague Dawley Rats. Int J Toxicol 2020; 39:294-306. [PMID: 32468881 DOI: 10.1177/1091581820928497] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This study consisted of a qualitative and quantitative assessment of neuropathological changes in kainic acid (KA)-treated adult male rats. Rats were administered a single 10 mg/kg intraperitoneal injection of KA or the same volume of saline and sacrificed 24 or 48 hours posttreatment. Brains were collected, sectioned coronally (∼ 81 slices), and stained with amino cupric silver to reveal degenerative changes. For qualitative assessment of neural degeneration, sectioned material was evaluated by a board-certified pathologist, and the level of degeneration was graded based upon a 4-point scale. For measurement of quantitative neural degeneration in response to KA treatment, the HALO digital image analysis software tool was used. Quantitative measurements of specific regions within the brain were obtained from silver-stained tissue sections with quantitation based on stain color and optical density. This quantitative evaluation method identified degeneration primarily in the cerebral cortex, septal nuclei, amygdala, olfactory bulb, hippocampus, thalamus, and hypothalamus. The KA-produced neuronal degeneration in the cortex was primarily in the piriform, insular, rhinal, and cingulate areas. In the hippocampus, the dentate gyrus was found to be the most affected area. Our findings indicate global neurotoxicity due to KA treatment. Certain brain structures exhibited more degeneration than others, reflecting differential sensitivity or vulnerability of neurons to KA.
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Affiliation(s)
| | - Serguei Liachenko
- National Center for Toxicological Research, NCTR/DNT, Jefferson, AR, USA
| | - Sumit Sarkar
- National Center for Toxicological Research, NCTR/DNT, Jefferson, AR, USA
| | - Merle Paule
- National Center for Toxicological Research, NCTR/DNT, Jefferson, AR, USA
| | - Geeta Negi
- US Food and Drug Administration, CDER/OPQ, Silver Spring, MD, USA
| | - Jai P Pandey
- US Food and Drug Administration, CDER/OPQ, Silver Spring, MD, USA
| | - Joseph P Hanig
- US Food and Drug Administration, CDER/OPQ, Silver Spring, MD, USA
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Fuscoe JC, Vijay V, Hanig JP, Han T, Ren L, Greenhaw JJ, Beger RD, Pence LM, Shi Q. Hepatic Transcript Profiles of Cytochrome P450 Genes Predict Sex Differences in Drug Metabolism. Drug Metab Dispos 2020; 48:447-458. [PMID: 32193355 PMCID: PMC7250365 DOI: 10.1124/dmd.119.089367] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 02/21/2020] [Indexed: 12/13/2022] Open
Abstract
Safety assessments of new drug candidates are an important part of the drug development and approval process. Often, possible sex-associated susceptibilities are not adequately addressed, and better assessment tools are needed. We hypothesized that hepatic transcript profiles of cytochrome P450 (P450) enzymes can be used to predict sex-associated differences in drug metabolism and possible adverse events. Comprehensive hepatic transcript profiles were generated for F344 rats of both sexes at nine ages, from 2 weeks (preweaning) to 104 weeks (elderly). Large differences in the transcript profiles of 29 drug metabolizing enzymes and transporters were found between adult males and females (8-52 weeks). Using the PharmaPendium data base, 41 drugs were found to be metabolized by one or two P450 enzymes encoded by sexually dimorphic mRNAs and thus were candidates for evaluation of possible sexually dimorphic metabolism and/or toxicities. Suspension cultures of primary hepatocytes from three male and three female adult rats (10-13 weeks old) were used to evaluate the metabolism of 11 drugs predicted to have sexually dimorphic metabolism. The pharmacokinetics of the drug or its metabolite was analyzed by liquid chromatography/tandem mass spectrometry using multiple reaction monitoring. Of those drugs with adequate metabolism, the predicted significant sex-different metabolism was found for six of seven drugs, with half-lives 37%-400% longer in female hepatocytes than in male hepatocytes. Thus, in this rat model, transcript profiles may allow identification of potential sex-related differences in drug metabolism. SIGNIFICANCE STATEMENT: The present study showed that sex-different expression of genes coding for drug metabolizing enzymes, specifically cytochrome P450s, could be used to predict sex-different drug metabolism and, thus, provide a new tool for protecting susceptible subpopulations from possible adverse drug events.
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Affiliation(s)
- James C Fuscoe
- Division of Systems Biology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (J.C.F., V.V., T.H., L.R., J.J.G., R.D.B., L.M.P., Q.S.); and Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland (J.P.H.)
| | - Vikrant Vijay
- Division of Systems Biology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (J.C.F., V.V., T.H., L.R., J.J.G., R.D.B., L.M.P., Q.S.); and Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland (J.P.H.)
| | - Joseph P Hanig
- Division of Systems Biology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (J.C.F., V.V., T.H., L.R., J.J.G., R.D.B., L.M.P., Q.S.); and Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland (J.P.H.)
| | - Tao Han
- Division of Systems Biology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (J.C.F., V.V., T.H., L.R., J.J.G., R.D.B., L.M.P., Q.S.); and Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland (J.P.H.)
| | - Lijun Ren
- Division of Systems Biology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (J.C.F., V.V., T.H., L.R., J.J.G., R.D.B., L.M.P., Q.S.); and Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland (J.P.H.)
| | - James J Greenhaw
- Division of Systems Biology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (J.C.F., V.V., T.H., L.R., J.J.G., R.D.B., L.M.P., Q.S.); and Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland (J.P.H.)
| | - Richard D Beger
- Division of Systems Biology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (J.C.F., V.V., T.H., L.R., J.J.G., R.D.B., L.M.P., Q.S.); and Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland (J.P.H.)
| | - Lisa M Pence
- Division of Systems Biology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (J.C.F., V.V., T.H., L.R., J.J.G., R.D.B., L.M.P., Q.S.); and Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland (J.P.H.)
| | - Qiang Shi
- Division of Systems Biology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, Arkansas (J.C.F., V.V., T.H., L.R., J.J.G., R.D.B., L.M.P., Q.S.); and Center for Drug Evaluation and Research, US Food and Drug Administration, Silver Spring, Maryland (J.P.H.)
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Bowyer JF, Sarkar S, Burks SM, Hess JN, Tolani S, O'Callaghan JP, Hanig JP. Microglial activation and responses to vasculature that result from an acute LPS exposure. Neurotoxicology 2020; 77:181-192. [PMID: 32014511 DOI: 10.1016/j.neuro.2020.01.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 01/29/2020] [Accepted: 01/31/2020] [Indexed: 12/22/2022]
Abstract
Bacterial cell wall endotoxins, i.e. lipopolysaccharides (LPS), are some of the original compounds shown to evoke the classic signs of systemic inflammation/innate immune response and neuroinflammation. The term neuroinflammation often is used to infer the elaboration of proinflammatory mediators by microglia elicited by neuronal targeted activity. However, it also is possible that the microglia are responding to vasculature through several signaling mechanisms. Microglial activation relative to the vasculature in the hippocampus and parietal cortex was determined after an acute exposure of a single subcutaneous injection of 2 mg/kg LPS. Antibodies to allograft inflammatory factor (Aif1, a.k.a. Iba1) were used to track and quantify morphological changes in microglia. Immunostaining of platelet/endothelial cell adhesion molecule 1 (Pecam1, a.k.a. Cd31) was used to visualize vasculature in the forebrain and glial acidic fibrillary protein (GFAP) to visualize astrocytes. Neuroinflammation and other aspects of neurotoxicity were evaluated histologically at 3 h, 6 h, 12 h, 24 h, 3 d and 14 d following LPS exposure. LPS did not cause neurodegeneration as determined by Fluoro Jade C labeling. Also, there were no signs of mouse IgG leakage from brain vasculature due to LPS. Some changes in microglia size occurred at 6 h, but by 12 h microglial activation had begun with the combined soma and proximal processes size increasing significantly (1.5-fold). At 24 h, almost all the microglia soma and proximal processes in the hippocampus, parietal cortex, and thalamus were closely associated with the vasculature and had increased almost 2.0-fold in size. In many areas where microglia were juxtaposed to vasculature, astrocytic endfeet appeared to be displaced. The microglial activation had subsided slightly by 3 d with microglial size 1.6-fold that of control. We hypothesize that acute LPS activation can result in vascular mediated microglial responses through several mechanisms: 1) binding to Cd14 and Tlr4 receptors on microglia processes residing on vasculature; 2) damaging vasculature and causing the release of cytokines; and 3) possibly astrocytic endfeet damage resulting in cytokine release. These acute responses may serve as an adaptive mechanism to exposure to circulating LPS where the microglia surround the vasculature. This could further prevent the pathogen(s) circulating in blood from entering the brain. However, diverting microglial interactions away from synaptic remodeling and other types of microglial interactions with neurons may have adverse effects on neuronal function.
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Affiliation(s)
- John F Bowyer
- Division of Neurotoxicology, National Center for Toxicology/ FDA, Jefferson, AR 72079, USA
| | - Sumit Sarkar
- Division of Neurotoxicology, National Center for Toxicology/ FDA, Jefferson, AR 72079, USA.
| | - Susan M Burks
- Division of Neurotoxicology, National Center for Toxicology/ FDA, Jefferson, AR 72079, USA
| | - Jade N Hess
- Division of Neurotoxicology, National Center for Toxicology/ FDA, Jefferson, AR 72079, USA
| | - Serena Tolani
- Division of Neurotoxicology, National Center for Toxicology/ FDA, Jefferson, AR 72079, USA
| | - James P O'Callaghan
- Health Effects Laboratory Division, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health Morgantown, WV 26505, USA
| | - Joseph P Hanig
- Center for Drug Evaluation and Research/ FDA Silver Spring, MD 20993, USA
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Liu F, Liu S, Patterson TA, Fogle C, Hanig JP, Slikker W, Wang C. Effects of Xenon-Based Anesthetic Exposure on the Expression Levels of Polysialic Acid Neural Cell Adhesion Molecule (PSA-NCAM) on Human Neural Stem Cell-Derived Neurons. Mol Neurobiol 2019; 57:217-225. [PMID: 31522383 DOI: 10.1007/s12035-019-01771-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 08/29/2019] [Indexed: 12/19/2022]
Abstract
Numerous studies suggest a long duration of anesthesia during the late gestation period and infancy is associated with an increased risk of neuronal damage and neurocognitive impairment. The noble gas xenon is an anesthetic that is reported to have neuroprotective effects in some circumstances at certain concentrations. Currently, the effects of xenon on the brain and its potential neuroprotective properties, and/or the effects of xenon used in combination with other anesthetics, are not clearly understood and some reported data appear contradictory. In the present study, human neural stem cells were employed as a human-relevant model to evaluate the effects of xenon when it was co-administered with propofol, a frequently used anesthetic in pediatric anesthesia, and to understand the mechanism(s). The expression of polysialic acid (PSA) neural cell adhesion molecule (NCAM) on human neural stem cell-differentiated neurons was investigated as a key target molecule. PSA is a specific marker of developing neurons. It is essential for neuronal viability and plasticity. Human neural stem cells were maintained in neural differentiation medium and directed to differentiate into neuronal and glial lineages, and were exposed to propofol (50 μM) for 16 h in the presence or absence of xenon (33%). The neural stem cell-derived neurons were characterized by labelling cells with PSA-NCAM, after 5 days of differentiation. Propofol- and/or xenon-induced neurotoxicities were determined by measuring PSA immunoreactivity. A time course study showed that neuronal cell surface PSA was clearly cleaved off from NCAM by endoneuraminidase N (Endo-N), and eliminated PSA immunostaining was not re-expressed 4, 8, or 16 h after Endo-N washout. However, in the presence of 33% xenon, intense PSA staining on neuronal cell surface and processes was evident 16 h after Endo-N washout. In addition, prolonged (16 h) propofol exposure significantly decreased the positive rate of PSA-labeled neurons. When combined with xenon, propofol's adverse effects on neurons were attenuated. This work, conducted on the human neural stem cell-derived models, has provided evidence of the beneficiary effects of xenon on neurons and helps develop xenon-based anesthesia regimens in the pediatric population.
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Affiliation(s)
- Fang Liu
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR, USA.
| | - Shuliang Liu
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR, USA
| | - Tucker A Patterson
- Office of Director, National Center for Toxicological Research/FDA, Jefferson, AR, USA
| | - Charles Fogle
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR, USA
| | - Joseph P Hanig
- Office of Pharmaceutical Quality, Center for Drug Evaluation and Research/FDA, Silver Spring, MD, USA
| | - William Slikker
- Office of Director, National Center for Toxicological Research/FDA, Jefferson, AR, USA
| | - Cheng Wang
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR, USA
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Camacho L, Silva CS, Hanig JP, Schleimer RP, George NI, Bowyer JF. Identification of whole blood mRNA and microRNA biomarkers of tissue damage and immune function resulting from amphetamine exposure or heat stroke in adult male rats. PLoS One 2019; 14:e0210273. [PMID: 30779732 PMCID: PMC6380594 DOI: 10.1371/journal.pone.0210273] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 12/18/2018] [Indexed: 12/14/2022] Open
Abstract
This work extends the understanding of how toxic exposures to amphetamine (AMPH) adversely affect the immune system and lead to tissue damage. Importantly, it determines which effects of AMPH are and are not due to pronounced hyperthermia. Whole blood messenger RNA (mRNA) and whole blood and serum microRNA (miRNA) transcripts were identified in adult male Sprague-Dawley rats after exposure to toxic AMPH under normothermic conditions, AMPH when it produces pronounced hyperthermia, or environmentally-induced hyperthermia (EIH). mRNA transcripts with large increases in fold-change in treated relative to control rats and very low expression in the control group were a rich source of organ-specific transcripts in blood. When severe hyperthermia was produced by either EIH or AMPH, significant increases in circulating organ-specific transcripts for liver (Alb, Fbg, F2), pancreas (Spink1), bronchi/lungs (F3, Cyp4b1), bone marrow (Np4, RatNP-3b), and kidney (Cesl1, Slc22a8) were observed. Liver damage was suggested also by increased miR-122 levels in the serum. Increases in muscle/heart-enriched transcripts were produced by AMPH even in the absence of hyperthermia. Expression increases in immune-related transcripts, particularly Cd14 and Vcan, indicate that AMPH can activate the innate immune system in the absence of hyperthermia. Most transcripts specific for T-cells decreased 50–70% after AMPH exposure or EIH, with the noted exception of Ccr5 and Chst12. This is probably due to T-cells leaving the circulation and down-regulation of these genes. Transcript changes specific for B-cells or B-lymphoblasts in the AMPH and EIH groups ranged widely from decreasing ≈ 40% (Cd19, Cd180) to increasing 30 to 100% (Tk1, Ahsa1) to increasing ≥500% (Stip1, Ackr3). The marked increases in Ccr2, Ccr5, Pld1, and Ackr3 produced by either AMPH or EIH observed in vivo provide further insight into the initial immune system alterations that result from methamphetamine and AMPH abuse and could modify risk for HIV and other viral infections.
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Affiliation(s)
- Luísa Camacho
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas, United States of America
| | - Camila S. Silva
- Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas, United States of America
| | - Joseph P. Hanig
- Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, Maryland, United States of America
| | - Robert P. Schleimer
- Division of Allergy and Immunology, Northwestern Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Nysia I. George
- Division of Bioinformatics and Biostatistics, NCTR/U.S. Food and Drug Administration, Jefferson, Arkansas, United States of America
| | - John F. Bowyer
- Division of Neurotoxicology, NCTR/U.S. Food and Drug Administration, Jefferson, Arkansas, United States of America
- * E-mail:
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11
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Talpos JC, Chelonis JJ, Li M, Hanig JP, Paule MG. Early life exposure to extended general anesthesia with isoflurane and nitrous oxide reduces responsivity on a cognitive test battery in the nonhuman primate. Neurotoxicology 2019; 70:80-90. [DOI: 10.1016/j.neuro.2018.11.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 10/24/2018] [Accepted: 11/08/2018] [Indexed: 10/27/2022]
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12
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Slikker W, Han X, Liu F, Zhang X, Gu Q, Liu S, Paterson TA, Paule MG, Hanig JP, Wang C. Identifying Potential Biomarkers, Mechanisms and Protective Strategies for General Anesthetic‐Induced Neurotoxicity in the Developing Nonhuman Primate. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.691.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- William Slikker
- Office of the DirectorNational Center for Toxicological Research (NCTR)/FDAJeffersonAR
| | - Xianlin Han
- Barshop Institute for Longevity and Aging StudiesDepartment of MedicineUniversity of Texas Health Science CenterSan AntonioTX
| | - Fang Liu
- Division of NeurotoxicologyNational Center for Toxicological Research (NCTR)/FDAJeffersonAR
| | - Xuan Zhang
- Division of NeurotoxicologyNational Center for Toxicological Research (NCTR)/FDAJeffersonAR
| | - Qiang Gu
- Division of NeurotoxicologyNational Center for Toxicological Research (NCTR)/FDAJeffersonAR
| | - Shuliang Liu
- Division of NeurotoxicologyNational Center for Toxicological Research (NCTR)/FDAJeffersonAR
| | - Tucker A. Paterson
- Office of the DirectorNational Center for Toxicological Research (NCTR)/FDAJeffersonAR
| | - Merle G. Paule
- Division of NeurotoxicologyNational Center for Toxicological Research (NCTR)/FDAJeffersonAR
| | | | - Cheng Wang
- Division of NeurotoxicologyNational Center for Toxicological Research (NCTR)/FDAJeffersonAR
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13
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Wang C, Han X, Liu F, Patterson TA, Hanig JP, Paule MG, Slikker W. Lipid profiling as an effective approach for identifying biomarkers/adverse events associated with pediatric anesthesia. Toxicol Appl Pharmacol 2018; 354:191-195. [PMID: 29550513 DOI: 10.1016/j.taap.2018.03.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 02/20/2018] [Accepted: 03/12/2018] [Indexed: 12/13/2022]
Abstract
Adverse effects related to central nervous system (CNS) function in pediatric populations may, at times, be difficult, if not impossible to evaluate. Prolonged anesthetic exposure affects brain excitability and anesthesia during the most sensitive developmental stages and has been associated with mitochondrial dysfunction, aberrant lipid metabolism and synaptogenesis, subsequent neuronal damage, as well as long-term behavioral deficits. There has been limited research evaluating whether and how anesthetic agents affect cellular lipids, the most abundant components of the brain other than water. Therefore, this review discusses: (1) whether the observed anesthetic-induced changes in lipid profiles seen in preclinical studies represents early signs of neurotoxicity; (2) the potential mechanisms underlying anesthetic-induced brain injury; and (3) whether lipid biomarker(s) identified in preclinical studies can serve as markers for the early clinical detection of anesthetic-induced neurotoxicity.
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Affiliation(s)
- Cheng Wang
- Division of Neurotoxicology, National Center for Toxicological Research/Food and Drug Administration, Jefferson, AR 72079, USA.
| | - Xianlin Han
- Center for Metabolic Origins of Disease, Sanford Burnham Prebys Medical Discovery Institute at Lake Nona, Orlando, FL 32827, USA
| | - Fang Liu
- Division of Neurotoxicology, National Center for Toxicological Research/Food and Drug Administration, Jefferson, AR 72079, USA
| | - Tucker A Patterson
- National Center for Toxicological Research/Food and Drug Administration, Jefferson, AR 72079, USA
| | - Joseph P Hanig
- Center for Drug Evaluation and Research/Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Merle G Paule
- Division of Neurotoxicology, National Center for Toxicological Research/Food and Drug Administration, Jefferson, AR 72079, USA
| | - William Slikker
- National Center for Toxicological Research/Food and Drug Administration, Jefferson, AR 72079, USA
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14
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Imam SZ, He Z, Cuevas E, Rosas-Hernandez H, Lantz SM, Sarkar S, Raymick J, Robinson B, Hanig JP, Herr D, MacMillan D, Smith A, Liachenko S, Ferguson S, O'Callaghan J, Miller D, Somps C, Pardo ID, Slikker W, B Pierson J, Roberts R, Gong B, Tong W, Aschner M, J Kallman M, Calligaro D, Paule MG. Changes in the metabolome and microRNA levels in biological fluids might represent biomarkers of neurotoxicity: A trimethyltin study. Exp Biol Med (Maywood) 2017; 243:228-236. [PMID: 29105512 DOI: 10.1177/1535370217739859] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Neurotoxicity has been linked with exposure to a number of common drugs and chemicals, yet efficient, accurate, and minimally invasive methods to detect it are lacking. Fluid-based biomarkers such as those found in serum, plasma, urine, and cerebrospinal fluid have great potential due to the relative ease of sampling but at present, data on their expression and translation are lacking or inconsistent. In this pilot study using a trimethyl tin rat model of central nervous system toxicity, we have applied state-of-the-art assessment techniques to identify potential individual biomarkers and patterns of biomarkers in serum, plasma, urine or cerebral spinal fluid that may be indicative of nerve cell damage and degeneration. Overall changes in metabolites and microRNAs were observed in biological fluids that were associated with neurotoxic damage induced by trimethyl tin. Behavioral changes and magnetic resonance imaging T2 relaxation and ventricle volume changes served to identify animals that responded to the adverse effects of trimethyl tin. Impact statement These data will help design follow-on studies with other known neurotoxicants to be used to assess the broad applicability of the present findings. Together this approach represents an effort to begin to develop and qualify a set of translational biochemical markers of neurotoxicity that will be readily accessible in humans. Such biomarkers could prove invaluable for drug development research ranging from preclinical studies to clinical trials and may prove to assist with monitoring of the severity and life cycle of brain lesions.
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Affiliation(s)
- Syed Z Imam
- 1 Division of Neurotoxicology, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
| | - Zhen He
- 1 Division of Neurotoxicology, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
| | - Elvis Cuevas
- 1 Division of Neurotoxicology, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
| | | | - Susan M Lantz
- 1 Division of Neurotoxicology, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
| | - Sumit Sarkar
- 1 Division of Neurotoxicology, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
| | - James Raymick
- 1 Division of Neurotoxicology, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
| | - Bonnie Robinson
- 1 Division of Neurotoxicology, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
| | | | - David Herr
- 3 US EPA, 96653 NHEERL , Research Triangle Park, North Carolina, NC 27711, USA
| | - Denise MacMillan
- 3 US EPA, 96653 NHEERL , Research Triangle Park, North Carolina, NC 27711, USA
| | - Aaron Smith
- 4 Lilly, Lilly Corporate Center, Indianapolis, Indiana, IN 46285, USA
| | - Serguei Liachenko
- 1 Division of Neurotoxicology, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
| | - Sherry Ferguson
- 1 Division of Neurotoxicology, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
| | | | | | | | | | - William Slikker
- 1 Division of Neurotoxicology, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
| | | | - Ruth Roberts
- 8 Department of Biosciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Binsheng Gong
- 9 Division of Bioinformatics, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
| | - Weida Tong
- 9 Division of Bioinformatics, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
| | - Michael Aschner
- 10 Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Mary J Kallman
- 11 Kallman Preclinical Consulting, Greenfield, IN 46140, USA
| | - David Calligaro
- 3 US EPA, 96653 NHEERL , Research Triangle Park, North Carolina, NC 27711, USA
| | - Merle G Paule
- 1 Division of Neurotoxicology, US FDA, 4136 NCTR , Jefferson, AR 72079, USA
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15
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Bowyer JF, Tranter KM, Sarkar S, George NI, Hanig JP, Kelly KA, Michalovicz LT, Miller DB, O'Callaghan JP. Corticosterone and exogenous glucose alter blood glucose levels, neurotoxicity, and vascular toxicity produced by methamphetamine. J Neurochem 2017; 143:198-213. [PMID: 28792619 DOI: 10.1111/jnc.14143] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 08/01/2017] [Accepted: 08/04/2017] [Indexed: 12/29/2022]
Abstract
Our previous studies have raised the possibility that altered blood glucose levels may influence and/or be predictive of methamphetamine (METH) neurotoxicity. This study evaluated the effects of exogenous glucose and corticosterone (CORT) pretreatment alone or in combination with METH on blood glucose levels and the neural and vascular toxicity produced. METH exposure consisted of four sequential injections of 5, 7.5, 10, and 10 mg/kg (2 h between injections) D-METH. The three groups given METH in combination with saline, glucose (METH+Glucose), or CORT (METH+CORT) had significantly higher glucose levels compared to the corresponding treatment groups without METH except at 3 h after the last injection. At this last time point, the METH and METH+Glucose groups had lower levels than the non-METH groups, while the METH+CORT group did not. CORT alone or glucose alone did not significantly increase blood glucose. Mortality rates for the METH+CORT (40%) and METH+Glucose (44%) groups were substantially higher than the METH (< 10%) group. Additionally, METH+CORT significantly increased neurodegeneration above the other three METH treatment groups (≈ 2.5-fold in the parietal cortex). Thus, maintaining elevated levels of glucose during METH exposure increases lethality and may exacerbate neurodegeneration. Neuroinflammation, specifically microglial activation, was associated with degenerating neurons in the parietal cortex and thalamus after METH exposure. The activated microglia in the parietal cortex were surrounding vasculature in most cases and the extent of microglial activation was exacerbated by CORT pretreatment. Our findings show that acute CORT exposure and elevated blood glucose levels can exacerbate METH-induced vascular damage, neuroinflammation, neurodegeneration and lethality. Cover Image for this issue: doi. 10.1111/jnc.13819.
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Affiliation(s)
- John F Bowyer
- Division of Neurotoxicology, National Center for Toxicology/FDA, Jefferson, Arkansas, USA
| | - Karen M Tranter
- Division of Neurotoxicology, National Center for Toxicology/FDA, Jefferson, Arkansas, USA
| | - Sumit Sarkar
- Division of Neurotoxicology, National Center for Toxicology/FDA, Jefferson, Arkansas, USA
| | - Nysia I George
- Division of Bioinformatics and Biostatistics, National Center for Toxicological Research/FDA, Jefferson, Arkansas, USA
| | - Joseph P Hanig
- Center for Drug Evaluation and Research/FDA Silver Spring, Silver Spring, Maryland, USA
| | - Kimberly A Kelly
- Health Effects Laboratory Division, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health Morgantown, Morgantown, West Virginia, USA
| | - Lindsay T Michalovicz
- Health Effects Laboratory Division, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health Morgantown, Morgantown, West Virginia, USA
| | - Diane B Miller
- Health Effects Laboratory Division, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health Morgantown, Morgantown, West Virginia, USA
| | - James P O'Callaghan
- Health Effects Laboratory Division, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health Morgantown, Morgantown, West Virginia, USA
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16
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Liu S, Zhang X, Liu F, Paule MG, Callicott R, Newport GD, Ali SF, Patterson TA, Apana SM, Berridge MS, Maisha MP, Hanig JP, Slikker W, Wang C. The Utility of a Nonhuman Primate Model for Assessing Anesthetic-Induced Developmental Neurotoxicity. ACTA ACUST UNITED AC 2017. [DOI: 10.4303/jdar/236011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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17
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Sarkar S, Liachenko S, Paule MG, Bowyer J, Hanig JP. Brain endothelial dysfunction following pyrithiamine induced thiamine deficiency in the rat. Neurotoxicology 2016; 57:298-309. [PMID: 27984051 DOI: 10.1016/j.neuro.2016.10.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 10/24/2016] [Accepted: 10/25/2016] [Indexed: 10/20/2022]
Abstract
Prolonged vitamin B1 (thiamine) deficiency can lead to neurological disorders such as Wernicke's encephalopathy and Wernicke-Korsakoff Syndrome (WKS) in humans. These thiamine deficiency disorders have been attributed to vascular leakage, blood-brain barrier breakdown and neuronal loss in the diencephalon and brain stem. However, endothelial dysfunction following thiamine deficiency and its relationship to the phenomenon of neurodegeneration has not been clearly elucidated. The present study sought to begin to address this issue by evaluating vascular morphology and integrity in a pyrithiamine (PT)-induced rat model of thiamine deficiency. Adjacent brain sections were used to either assess vascular integrity through immunohistochemical localization of rat endothelial cell antigen (RECA-1) and endothelial brain barrier antigen (EBA-1) or neurodegeneration using the de Olmos cupric silver method. GFAP and CD11b immunolabeling was used to evaluate astrocytic and microglial/macrophagic changes. Extensive neurodegeneration occurred concomitant with both vascular damage (thinning and breakage) and microglial activation in the inferior olive, medial thalamic area, and medial geniculate nuclei of pyrithiamine treated rats. Likewise, glucose transporter-1 (Glut-1), which is mostly expressed in endothelial cells, was also severely decreased in this pyrithiamine induced thiamine deficient rat model. MRI scans of these animals prior to sacrifice show that the pyrithiamine induced thiamine deficient animals have abnormal T2 relaxation values, which are commensurate with, and possibly predictive of, the neurodegeneration and/or endothelial dysfunction subsequently observed histologically in these same animals.
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Affiliation(s)
- Sumit Sarkar
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR-72079, USA.
| | - Serguei Liachenko
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR-72079, USA
| | - Merle G Paule
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR-72079, USA
| | - John Bowyer
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Jefferson, AR-72079, USA
| | - Joseph P Hanig
- Office of Testing & Research, CDER/FDA, White Oak, MD-20993, USA
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18
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Roberts RA, Aschner M, Calligaro D, Guilarte TR, Hanig JP, Herr DW, Hudzik TJ, Jeromin A, Kallman MJ, Liachenko S, Lynch JJ, Miller DB, Moser VC, O'Callaghan JP, Slikker W, Paule MG. Translational Biomarkers of Neurotoxicity: A Health and Environmental Sciences Institute Perspective on the Way Forward. Toxicol Sci 2016; 148:332-40. [PMID: 26609132 PMCID: PMC4659531 DOI: 10.1093/toxsci/kfv188] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Neurotoxicity has been linked to a number of common drugs and chemicals, yet efficient and accurate methods to detect it are lacking. There is a need for more sensitive and specific biomarkers of neurotoxicity that can help diagnose and predict neurotoxicity that are relevant across animal models and translational from nonclinical to clinical data. Fluid-based biomarkers such as those found in serum, plasma, urine, and cerebrospinal fluid (CSF) have great potential due to the relative ease of sampling compared with tissues. Increasing evidence supports the potential utility of fluid-based biomarkers of neurotoxicity such as microRNAs, F2-isoprostanes, translocator protein, glial fibrillary acidic protein, ubiquitin C-terminal hydrolase L1, myelin basic protein, microtubule-associated protein-2, and total tau. However, some of these biomarkers such as those in CSF require invasive sampling or are specific to one disease such as Alzheimer’s, while others require further validation. Additionally, neuroimaging methodologies, including magnetic resonance imaging, magnetic resonance spectroscopy, and positron emission tomography, may also serve as potential biomarkers and have several advantages including being minimally invasive. The development of biomarkers of neurotoxicity is a goal shared by scientists across academia, government, and industry and is an ideal topic to be addressed via the Health and Environmental Sciences Institute (HESI) framework which provides a forum to collaborate on key challenging scientific topics. Here we utilize the HESI framework to propose a consensus on the relative potential of currently described biomarkers of neurotoxicity to assess utility of the selected biomarkers using a nonclinical model.
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Affiliation(s)
- Ruth A Roberts
- *ApconiX, BioHub at Alderley Park, Cheshire SK10 4TG, UK;
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York 10461
| | - David Calligaro
- Eli Lilly & Co., Pharmacology/Toxicology Research Lilly Research Labs, A Division of Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285
| | | | - Joseph P Hanig
- U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Silver Spring, Maryland 20993
| | - David W Herr
- US EPA, Toxicology Assessment Division, NHEERL, Research Triangle Park, North Carolona 27711
| | | | | | - Mary J Kallman
- Covance, Inc., 8211 SciCor Drive, Indianapolis, Indiana 46214
| | - Serguei Liachenko
- **U.S. Food and Drug Administration, National Center for Toxicological Research, Jefferson, Arkansas 72079
| | | | - Diane B Miller
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505; and
| | - Virginia C Moser
- US EPA, Toxicology Assessment Division, NHEERL, Research Triangle Park, North Carolona 27711
| | - James P O'Callaghan
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505; and
| | - William Slikker
- **U.S. Food and Drug Administration, National Center for Toxicological Research, Jefferson, Arkansas 72079
| | - Merle G Paule
- Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505; and
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19
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Ramu J, Konak T, Paule MG, Hanig JP, Liachenko S. Longitudinal diffusion tensor imaging of the rat brain after hexachlorophene exposure. Neurotoxicology 2016; 56:225-232. [PMID: 27555423 DOI: 10.1016/j.neuro.2016.08.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 08/17/2016] [Accepted: 08/17/2016] [Indexed: 12/28/2022]
Abstract
Longitudinal MRI employing diffusion tensor imaging and T2 mapping approaches has been applied to investigate the mechanisms of white matter damage caused by acute hexachlorophene neurotoxicity in rats in vivo. Male Sprague-Dawley rats were administered hexachlorophene orally once a day for five consecutive days at a dose of 30mg/kg and were monitored in 7T MRI scanner at days 0 (baseline), 3, 6, 13, and 20 following the first hexachlorophene dose. Quantitative T2 maps as well as a number of diffusion tensor parameters (fractional anisotropy, radial and axial diffusivity, apparent diffusion coefficient, and trace) were calculated from corresponding MR images. T2, as well as all diffusion tensor derived parameters (except fractional anisotropy) showed significant changes during the course of neurotoxicity development. These changes peaked at 6days after the first dose of hexachlorophene (one day after the last dose) and recovered to practically baseline levels at the end of observation (20days from the first dose). While such changes in diffusivity and T2 relaxation clearly demonstrate myelin perturbations consistent with edema, the lack of changes of fractional anisotropy suggests that the structure of the myelin sheath was not disrupted significantly by hexachlorophene in this study. This is also confirmed by the rapid recovery of all observed MRI parameters after cessation of hexachlorophene exposure.
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Affiliation(s)
- Jaivijay Ramu
- Division of Neurotoxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR, United States.
| | - Tetyana Konak
- Division of Neurotoxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR, United States.
| | - Merle G Paule
- Division of Neurotoxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR, United States.
| | - Joseph P Hanig
- Center for Drug Evaluation and Research, Food and Drug Administration, White Oak, MD, United States.
| | - Serguei Liachenko
- Division of Neurotoxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR, United States.
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20
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Bowyer JF, Sarkar S, Tranter KM, Hanig JP, Miller DB, O'Callaghan JP. Vascular-directed responses of microglia produced by methamphetamine exposure: indirect evidence that microglia are involved in vascular repair? J Neuroinflammation 2016; 13:64. [PMID: 26970737 PMCID: PMC4789274 DOI: 10.1186/s12974-016-0526-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Accepted: 03/03/2016] [Indexed: 11/24/2022] Open
Abstract
Background Brain microglial activations and damage responses are most commonly associated with neurodegeneration or systemic innate immune system activation. Here, we used histological methods to focus on microglial responses that are directed towards brain vasculature, previously undescribed, after a neurotoxic exposure to methamphetamine. Methods Male rats were given doses of methamphetamine that produce pronounced hyperthermia, hypertension, and toxicity. Identification of microglia and microglia-like cells (pericytes and possibly perivascular cells) was done using immunoreactivity to allograft inflammatory factor 1 (Aif1 a.k.a Iba1) and alpha M integrin (Itgam a.k.a. Cd11b) while vasculature endothelium was identified using rat endothelial cell antigen 1 (RECA-1). Regions of neuronal, axonal, and nerve terminal degeneration were determined using Fluoro-Jade C. Results Dual labeling of vasculature (RECA-1) and microglia (Iba1) showed a strong association of hypertrophied cells surrounding and juxtaposed to vasculature in the septum, medial dorsal hippocampus, piriform cortex, and thalamus. The Iba1 labeling was more pronounced in the cell body while Cd11b more so in the processes of activated microglia. These regions have been previously identified to have vascular leakage after neurotoxic methamphetamine exposure. Dual labeling with Fluoro-Jade C and Iba1 indicated that there was minimal or no evidence of neuronal damage in the septum and hippocampus where many hypertrophied Iba1-labeled cells were found to be associated with vasculature. Although microglial activation around the prominent neurodegeneration was found in the thalamus, there were also many examples of activated microglia associated with vasculature. Conclusions The data implicate microglia, and possibly related cell types, in playing a major role in responding to methamphetamine-induced vascular damage, and possibly repair, in the absence of neurodegeneration. Identifying brain regions with hypertrophied/activated microglial-like cells associated with vasculature has the potential for identifying regions of more subtle examples of vascular damage and BBB compromise. Electronic supplementary material The online version of this article (doi:10.1186/s12974-016-0526-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- John F Bowyer
- Division of Neurotoxicology, National Center for Toxicology/FDA, Jefferson, AR, 72079, USA. .,National Center for Toxicological Research/FDA, 3900 NCTR Road, HFT-132, Jefferson, AR, 72079, USA.
| | - Sumit Sarkar
- Division of Neurotoxicology, National Center for Toxicology/FDA, Jefferson, AR, 72079, USA
| | - Karen M Tranter
- Division of Neurotoxicology, National Center for Toxicology/FDA, Jefferson, AR, 72079, USA
| | - Joseph P Hanig
- Center for Drug Evaluation and Research/FDA, Silver Spring, MD, 20993, USA
| | - Diane B Miller
- Health Effects Laboratory Division, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
| | - James P O'Callaghan
- Health Effects Laboratory Division, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, Morgantown, WV, 26505, USA
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Bowyer JF, Tranter KM, Hanig JP, Crabtree NM, Schleimer RP, George NI. Evaluating the Stability of RNA-Seq Transcriptome Profiles and Drug-Induced Immune-Related Expression Changes in Whole Blood. PLoS One 2015; 10:e0133315. [PMID: 26177368 PMCID: PMC4503719 DOI: 10.1371/journal.pone.0133315] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 06/24/2015] [Indexed: 12/01/2022] Open
Abstract
Methods were developed to evaluate the stability of rat whole blood expression obtained from RNA sequencing (RNA-seq) and assess changes in whole blood transcriptome profiles in experiments replicated over time. Expression was measured in globin-depleted RNA extracted from the whole blood of Sprague-Dawley rats, given either saline (control) or neurotoxic doses of amphetamine (AMPH). The experiment was repeated four times (paired control and AMPH groups) over a 2-year span. The transcriptome of the control and AMPH-treated groups was evaluated on: 1) transcript levels for ribosomal protein subunits; 2) relative expression of immune-related genes; 3) stability of the control transcriptome over 2 years; and 4) stability of the effects of AMPH on immune-related genes over 2 years. All, except one, of the 70 genes that encode the 80s ribosome had levels that ranked in the top 5% of all mean expression levels. Deviations in sequencing performance led to significant changes in the ribosomal transcripts. The overall expression profile of immune-related genes and genes specific to monocytes, T-cells or B-cells were well represented and consistent within treatment groups. There were no differences between the levels of ribosomal transcripts in time-matched control and AMPH groups but significant differences in the expression of immune-related genes between control and AMPH groups. AMPH significantly increased expression of some genes related to monocytes but down-regulated those specific to T-cells. These changes were partially due to changes in the two types of leukocytes present in blood, which indicate an activation of the innate immune system by AMPH. Thus, the stability of RNA-seq whole blood transcriptome can be verified by assessing ribosomal protein subunits and immune-related gene expression. Such stability enables the pooling of samples from replicate experiments to carry out differential expression analysis with acceptable power.
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Affiliation(s)
- John F. Bowyer
- Division of Neurotoxicology, National Center for Toxicological Research, United States Food and Drug Administration, Jefferson, Arkansas, United States of America
- * E-mail:
| | - Karen M. Tranter
- Division of Neurotoxicology, National Center for Toxicological Research, United States Food and Drug Administration, Jefferson, Arkansas, United States of America
| | - Joseph P. Hanig
- Center for Drug Evaluation and Research, United States Food and Drug Administration, Silver Spring, Maryland, United States of America
| | - Nathaniel M. Crabtree
- Division of Neurotoxicology, National Center for Toxicological Research, United States Food and Drug Administration, Jefferson, Arkansas, United States of America
| | - Robert P. Schleimer
- Division of Allergy and Immunology, Northwestern Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Nysia I. George
- Division of Bioinformatics and Biostatistics, National Center for Toxicological Research, United States Food and Drug Administration, Jefferson, Arkansas, United States of America
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Slikker W, Liu F, Rainosek SW, Patterson TA, Sadovova N, Hanig JP, Paule MG, Wang C. Ketamine-Induced Toxicity in Neurons Differentiated from Neural Stem Cells. Mol Neurobiol 2015; 52:959-69. [DOI: 10.1007/s12035-015-9248-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Indexed: 11/28/2022]
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Majdi JA, Qian H, Li Y, Langsner RJ, Shea KI, Agrawal A, Hammer DX, Hanig JP, Cohen ED. The use of time-lapse optical coherence tomography to image the effects of microapplied toxins on the retina. Invest Ophthalmol Vis Sci 2014; 56:587-97. [PMID: 25525175 DOI: 10.1167/iovs.14-15594] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE We developed a novel technique for accelerated drug screening and retinotoxin characterization using time-lapse optical coherence tomography (OCT) and a drug microapplication device. METHODS Using an ex vivo rabbit eyecup preparation, we studied retinotoxin effects in real-time by microperfusing small retinal areas under a transparent fluoropolymer tube. Known retinotoxic agents were applied to the retina for 5-minute periods, while changes in retinal structure, thickness, and reflectance were monitored with OCT. The OCT images of two agents with dissimilar mechanisms, cyanide and kainic acid, were compared to their structural changes seen histologically. RESULTS We found the actions of retinotoxic agents tested could be classified broadly into two distinct types: (1) agents that induce neuronal depolarization, such as kainic acid, causing increases in OCT reflectivity or thickness of the inner plexiform and nuclear layers, and decreased reflectivity of the outer retina; and (2) agents that disrupt mitochondrial function, such as cyanide, causing outer retinal structural changes as evidenced by a reduction in the OCT reflectivity of the photoreceptor outer segment and pigment epithelium layers. CONCLUSIONS Retinotoxin-induced changes in retinal layer reflectivity and thickness under the microperfusion tube in OCT images closely matched the histological evidence of retinal injury. Time-lapse OCT imaging of the microperfused local retina has the potential to accelerate drug retinotoxicological screening and expand the use of OCT as an evaluation tool for preclinical animal testing.
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Affiliation(s)
- Joseph A Majdi
- Division of Biomedical Physics, Office of Science and Engineering Labs, Center for Devices and Radiological Health, Food and Drug Administration, White Oak Federal Research Labs, Silver Spring, Maryland, United States
| | - Haohua Qian
- National Eye Institute, Visual Function Core, National Institutes of Health, Bethesda, Maryland, United States
| | - Yichao Li
- National Eye Institute, Visual Function Core, National Institutes of Health, Bethesda, Maryland, United States
| | - Robert J Langsner
- Division of Biomedical Physics, Office of Science and Engineering Labs, Center for Devices and Radiological Health, Food and Drug Administration, White Oak Federal Research Labs, Silver Spring, Maryland, United States
| | - Katherine I Shea
- Office of Testing and Research, Center for Drug Evaluation and Research, Food and Drug Administration, White Oak Federal Research Labs, Silver Spring, Maryland, United States
| | - Anant Agrawal
- Division of Biomedical Physics, Office of Science and Engineering Labs, Center for Devices and Radiological Health, Food and Drug Administration, White Oak Federal Research Labs, Silver Spring, Maryland, United States
| | - Daniel X Hammer
- Division of Biomedical Physics, Office of Science and Engineering Labs, Center for Devices and Radiological Health, Food and Drug Administration, White Oak Federal Research Labs, Silver Spring, Maryland, United States
| | - Joseph P Hanig
- Office of Testing and Research, Center for Drug Evaluation and Research, Food and Drug Administration, White Oak Federal Research Labs, Silver Spring, Maryland, United States
| | - Ethan D Cohen
- Division of Biomedical Physics, Office of Science and Engineering Labs, Center for Devices and Radiological Health, Food and Drug Administration, White Oak Federal Research Labs, Silver Spring, Maryland, United States
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Slavov SH, Wilkes JG, Buzatu DA, Kruhlak NL, Willard JM, Hanig JP, Beger RD. Computational identification of a phospholipidosis toxicophore using 13 C and 15 N NMR-distance based fingerprints. Bioorg Med Chem 2014; 22:6706-6714. [DOI: 10.1016/j.bmc.2014.08.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 08/13/2014] [Accepted: 08/18/2014] [Indexed: 10/24/2022]
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Bowyer JF, Hanig JP. Amphetamine- and methamphetamine-induced hyperthermia: Implications of the effects produced in brain vasculature and peripheral organs to forebrain neurotoxicity. Temperature (Austin) 2014; 1:172-82. [PMID: 27626044 PMCID: PMC5008711 DOI: 10.4161/23328940.2014.982049] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 10/22/2014] [Accepted: 10/27/2014] [Indexed: 12/20/2022] Open
Abstract
The adverse effects of amphetamine- (AMPH) and methamphetamine- (METH) induced hyperthermia on vasculature, peripheral organs and peripheral immune system are discussed. Hyperthermia alone does not produce amphetamine-like neurotoxicity but AMPH and METH exposures that do not produce hyperthermia (≥40°C) are minimally neurotoxic. Hyperthermia likely enhances AMPH and METH neurotoxicity directly through disruption of protein function, ion channels and enhanced ROS production. Forebrain neurotoxicity can also be indirectly influenced through the effects of AMPH- and METH- induced hyperthermia on vasculature. The hyperthermia and the hypertension produced by high doses amphetamines are a primary cause of transient breakdowns in the blood-brain barrier (BBB) resulting in concomitant regional neurodegeneration and neuroinflammation in laboratory animals. This BBB breakdown can occur in the amygdala, thalamus, striatum, sensory and motor cortex and hippocampus. Under these conditions, repetitive seizures greatly enhance neurodegeneration in hippocampus, thalamus and amygdala. Even when the BBB is less disrupted, AMPH- or METH- induced hyperthermia effects on brain vasculature may play a role in neurotoxicity. In this case, striatal and cortical vascular function are adversely affected, and even greater ROS, immune and damage responses are seen in the meninges and cortical surface vasculature. Finally, muscle and liver damage and elevated cytokines in blood can result when amphetamines produce hyperthermia. Proteins, from damaged muscle may activate the peripheral immune system and exacerbate liver damage. Liver damage can further increase cytokine levels, immune system activation and increase ammonia levels. These effects could potentially enhance vascular damage and neurotoxicity.
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Sarkar S, Raymick J, Mann D, Bowyer JF, Hanig JP, Schmued LC, Paule MG, Chigurupati S. Neurovascular changes in acute, sub-acute and chronic mouse models of Parkinson's disease. Curr Neurovasc Res 2014; 11:48-61. [PMID: 24274908 DOI: 10.2174/1567202610666131124234506] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 11/16/2013] [Accepted: 11/17/2013] [Indexed: 11/22/2022]
Abstract
Although selective neurodegeneration of nigro-striatal dopaminergic neurons is widely accepted as a cause of Parkinson's disease (PD), the role of vascular components in the brain in PD pathology is not well understood. However, the neurodegeneration seen in PD is known to be associated with neuroinflammatory-like changes that can affect or be associated with brain vascular function. Thus, dysfunction of the capillary endothelial cell component of neurovascular units present in the brain may contribute to the damage to dopaminergic neurons that occurs in PD. An animal model of PD employing acute, sub-acute and chronic exposures of mice to methyl-phenyl-tetrahydropyridine (MPTP) was used to determine the extent to which brain vasculature may be damaged in PD. Fluoro-Turquoise gelatin labeling of microvessels and endothelial cells was used to determine the extent of vascular damage produced by MPTP. In addition, tyrosine hydroxylase (TH) and NeuN were employed to detect and quantify dopaminergic neuron damage in the striatum (CPu) and substantia nigra (SNc). Gliosis was evaluated through GFAP immunohistochemistry. MPTP treatment drastically reduced TH immunoreactive neurons in the SNc (20.68 ± 2.83 in acute; 22.98 ± 2.14 in sub-acute; 10.20 ± 2.24 in chronic vs 34.88 ± 2.91 in controls; p<0.001). Similarly, TH immunoreactive terminals were dramatically reduced in the CPu of MPTP treated mice. Additionally, all three MPTP exposures resulted in a decrease in the intensity, length, and number of vessels in both CPu and SNc. Degenerative vascular changes such as endothelial cell 'clusters' were also observed after MPTP suggesting that vasculature damage may be modifying the availability of nutrients and exposing blood cells and/or toxic substances to neurons and glia. In summary, vascular damage and degeneration could be an additional exacerbating factor in the progression of PD, and therapeutics that protect and insure vascular integrity may be novel treatments for PD.
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Affiliation(s)
| | | | | | | | | | | | | | - Srinivasulu Chigurupati
- Division of Neurotoxicology, National Center for Toxicological Research/FDA, Bldg. 53D, HFT-32, Jefferson-AR-72079, USA.
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Sarkar S, Chigurupati S, Raymick J, Mann D, Bowyer JF, Schmitt T, Beger RD, Hanig JP, Schmued LC, Paule MG. Neuroprotective effect of the chemical chaperone, trehalose in a chronic MPTP-induced Parkinson's disease mouse model. Neurotoxicology 2014; 44:250-62. [DOI: 10.1016/j.neuro.2014.07.006] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 07/14/2014] [Accepted: 07/15/2014] [Indexed: 10/25/2022]
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Liu F, Rainosek SW, Sadovova N, Fogle CM, Patterson TA, Hanig JP, Paule MG, Slikker W, Wang C. Protective effect of acetyl-l-carnitine on propofol-induced toxicity in embryonic neural stem cells. Neurotoxicology 2014; 42:49-57. [DOI: 10.1016/j.neuro.2014.03.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 03/21/2014] [Accepted: 03/21/2014] [Indexed: 10/25/2022]
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Levi MS, Patton RE, Hanig JP, Tranter KM, George NI, James LP, Davis KJ, Bowyer JF. Serum myoglobin, but not lipopolysaccharides, is predictive of AMPH-induced striatal neurotoxicity. Neurotoxicology 2013; 37:40-50. [PMID: 23608161 DOI: 10.1016/j.neuro.2013.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 03/19/2013] [Accepted: 04/05/2013] [Indexed: 01/08/2023]
Abstract
Determinants of amphetamine (AMPH)-induced neurotoxicity are poorly understood. The role of lipopolysaccharides (LPS) and organ injury in AMPH-induced neurotoxicity was examined in adult male Sprague-Dawley rats that were give AMPH and became hyperthermic during the exposure. Environmentally-induced hyperthermia (EIH) in the rat was compared to AMPH to determine whether AMPH-induced increases in LPS and peripheral toxicities were solely attributable to hyperthermia. Muscle, liver, and kidney function were determined biochemically at 3h or 1 day after AMPH or EIH exposure and histopathology at 1 day after treatment. Circulating levels of LPS were monitored (via limulus amoebocyte coagulation assay) during AMPH or EIH exposure. Blood LPS levels were detected in 40-50% of the AMPH and EIH rats, but the presence of LPS in the serum had no effect on organ damage or striatal dopamine depletions (neurotoxicity). In both CR and NCTR rats, serum bound urea nitrogen and creatinine levels increased at 3h after EIH or AMPH (2- to 3-fold above control) but subsided by 1 day. Alanine transaminase was increased (indicating liver dysfunction) by both AMPH and EIH at 3 h (2- to 10-fold above control) in CR rats, but the levels were not significantly different between the control and AMPH groups in NCTR animals. Mild liver necrosis was detected in 1 of 7 rats examined in the AMPH group and in 1 of 5 rats examined in the EIH group (only NCTR rats were examined). Serum myoglobin increased (indicating muscle damage) in both CR and NCTR rats at 3h and was more pronounced with AMPH (≈5-fold above control) than EIH. Our results indicate that: (1) "free" blood borne LPS often increases with EIH and AMPH but may not be necessary for striatal neurotoxicity and CNS immune responses; (2) liver or kidney dysfunction may result from muscle damage; however, it is not sufficient nor necessary to produce, but may exacerbate, neurotoxicity; (3) AMPH-induced serum myoglobin release is a potential biomarker and possibly a factor in AMPH-induced toxicity processes.
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Affiliation(s)
- Mark S Levi
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food & Drug Administration, Jefferson, AR 72079-9502, USA.
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Bowyer JF, Patterson TA, Saini UT, Hanig JP, Thomas M, Camacho L, George NI, Chen JJ. Comparison of the global gene expression of choroid plexus and meninges and associated vasculature under control conditions and after pronounced hyperthermia or amphetamine toxicity. BMC Genomics 2013; 14:147. [PMID: 23497014 PMCID: PMC3602116 DOI: 10.1186/1471-2164-14-147] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 02/21/2013] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND The meninges (arachnoid and pial membranes) and associated vasculature (MAV) and choroid plexus are important in maintaining cerebrospinal fluid (CSF) generation and flow. MAV vasculature was previously observed to be adversely affected by environmentally-induced hyperthermia (EIH) and more so by a neurotoxic amphetamine (AMPH) exposure. Herein, microarray and RT-PCR analysis was used to compare the gene expression profiles between choroid plexus and MAV under control conditions and at 3 hours and 1 day after EIH or AMPH exposure. Since AMPH and EIH are so disruptive to vasculature, genes related to vasculature integrity and function were of interest. RESULTS Our data shows that, under control conditions, many of the genes with relatively high expression in both the MAV and choroid plexus are also abundant in many epithelial tissues. These genes function in transport of water, ions, and solutes, and likely play a role in CSF regulation. Most genes that help form the blood-brain barrier (BBB) and tight junctions were also highly expressed in MAV but not in choroid plexus. In MAV, exposure to EIH and more so to AMPH decreased the expression of BBB-related genes such as Sox18, Ocln, and Cldn5, but they were much less affected in the choroid plexus. There was a correlation between the genes related to reactive oxidative stress and damage that were significantly altered in the MAV and choroid plexus after either EIH or AMPH. However, AMPH (at 3 hr) significantly affected about 5 times as many genes as EIH in the MAV, while in the choroid plexus EIH affected more genes than AMPH. Several unique genes that are not specifically related to vascular damage increased to a much greater extent after AMPH compared to EIH in the MAV (Lbp, Reg3a, Reg3b, Slc15a1, Sct and Fst) and choroid plexus (Bmp4, Dio2 and Lbp). CONCLUSIONS Our study indicates that the disruption of choroid plexus function and damage produced by AMPH and EIH is significant, but the changes may not be as pronounced as they are in the MAV, particularly for AMPH. Expression profiles in the MAV and choroid plexus differed to some extent and differences were not restricted to vascular related genes.
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Affiliation(s)
- John F Bowyer
- Division of Neurotoxicology, National Center for Toxicological Research, U,S, Food and Drug Administration, Jefferson, AR 72079-9502, USA.
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Liu F, Guo L, Zhang J, Rainosek SW, Shi L, Patterson TA, Li QZ, Sadovova N, Hanig JP, Paule MG, Slikker W, Wang C. Inhalation Anesthesia-Induced Neuronal Damage and Gene Expression Changes in Developing Rat Brain. Syst Pharmacol 2013; 1:1-9. [PMID: 29309069 PMCID: PMC5755976 DOI: 10.2478/sph-2012-0001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Nitrous Oxide (N2O), an N-methyl-D-aspartate (NMDA) receptor antagonist, and isoflurane (ISO), which acts on multiple receptors including postsynaptic gamma-aminobutyric acid (GABA) receptors, are frequently used inhalation anesthetics, alone or as a part of a balanced anesthetic regimen administered to pregnant women and to human neonates and infants requiring surgery. The current study investigated histological features and gene expression profiles in response to prolonged exposure to N2O or ISO alone, and their combination in developing rat brains. Postnatal day 7 rats were exposed to clinically-relevant concentrations of N2O (70%), ISO (1.0%) or N2O plus ISO (N2O + ISO) for 6 hours. The neurotoxic effects were evaluated and the brain tissues were harvested for RNA extraction 6 hours after anesthetic administration. The prolonged exposure to N2O + ISO produced elevated neuronal cell death as indicated by an increased number of TUNEL-positive cells in frontal cortical levels compared with control. No significant neurotoxic effects were observed in animals exposed to N2O or ISO alone. DNA microarray analysis revealed gene expression changes after N2O, ISO or N2O + ISO exposure. Differentially expressed genes (DEGs) from the N2O + ISO group were significantly associated with 45 pathways directly related to brain functions. Although the gene expression profiles from animals exposed to N2O or ISO alone were remarkably different from those of the control group, the pathways of these genes involved were not closely associated with neurons. These findings provide novel insights into the mechanisms by which N2O + ISO cause neurotoxicity in the developing brain, suggesting multiple factors are involved in the neuronal cell death-inducing effects (cascades) of N2O + ISO.
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Affiliation(s)
- Fang Liu
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food & Drug Administration, 3900 NCTR Rd., Jefferson, AR 72079 USA
| | - Lei Guo
- Division of Systems Toxicology, National Center for Toxicological Research, U.S. Food & Drug Administration, 3900 NCTR Rd., Jefferson, AR 72079 USA
| | - Jie Zhang
- Division of Systems Toxicology, National Center for Toxicological Research, U.S. Food & Drug Administration, 3900 NCTR Rd., Jefferson, AR 72079 USA
| | - Shuo W. Rainosek
- Department of Anesthesiology, University of Arkansas for Medical Science
| | - Leming Shi
- Division of Systems Toxicology, National Center for Toxicological Research, U.S. Food & Drug Administration, 3900 NCTR Rd., Jefferson, AR 72079 USA
| | - Tucker A. Patterson
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food & Drug Administration, 3900 NCTR Rd., Jefferson, AR 72079 USA
| | - Quan-Zhen Li
- Department of Immunology, Microarray Core Facility, University of Texas Southwestern Medical Center, 6000 Harry Hines Blvd., Dallas, TX 75390 USA
| | - Natalya Sadovova
- Toxicologic Pathology Associates, 3900 NCTR Rd., Jefferson, AR 72079 USA
| | - Joseph P. Hanig
- Center for Drug Evaluation and Research, FDA, Silver Spring, MD 20933 USA
| | - Merle G. Paule
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food & Drug Administration, 3900 NCTR Rd., Jefferson, AR 72079 USA
| | - William Slikker
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food & Drug Administration, 3900 NCTR Rd., Jefferson, AR 72079 USA
| | - Cheng Wang
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food & Drug Administration, 3900 NCTR Rd., Jefferson, AR 72079 USA
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Liu F, Patterson TA, Sadovova N, Zhang X, Liu S, Zou X, Hanig JP, Paule MG, Slikker W, Wang C. Ketamine-induced neuronal damage and altered N-methyl-D-aspartate receptor function in rat primary forebrain culture. Toxicol Sci 2012; 131:548-57. [PMID: 23065140 DOI: 10.1093/toxsci/kfs296] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Ketamine, a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist, is frequently used in pediatric general anesthesia. Accumulating evidence from animal experiments has demonstrated that ketamine causes neuronal cell death during the brain growth spurt. To elucidate the underlying mechanisms associated with ketamine-induced neuronal toxicity and search for approaches or agents to prevent ketamine's adverse effects on the developing brain, a primary nerve cell culture system was utilized. Neurons harvested from the forebrain of newborn rats were maintained under normal control conditions or exposed to either ketamine (10 µM) or ketamine plus L-carnitine (an antioxidant; 1-100 µM) for 24h, followed by a 24-h withdrawal period. Ketamine exposure resulted in elevated NMDA receptor (NR1) expression, increased generation of reactive oxygen species (ROS) as indicated by higher levels of 8-oxoguanine production, and enhanced neuronal damage. Coadministration of L-carnitine significantly diminished ROS generation and provided near complete protection of neurons from ketamine-induced cell death. NMDA receptors regulate channels that are highly permeable to calcium, and calcium imaging data demonstrated that neurons exposed to ketamine had a significantly elevated amplitude of calcium influx and higher intracellular free calcium concentrations ([Ca(2+)]i) evoked by NMDA (50 µM), compared with control neurons. These findings suggest that prolonged ketamine exposure produces an increase in NMDA receptor expression (compensatory upregulation), which allows for a higher/toxic influx of calcium into neurons once ketamine is removed from the system, leading to elevated ROS generation and neuronal cell death. L-Carnitine appears to be a promising agent in preventing or reversing ketamine's toxic effects on neurons at an early developmental stage.
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Affiliation(s)
- Fang Liu
- Division of Neurotoxicology, National Center for Toxicological Research, Food and Drug Administration, 3900 NCTR Rd., Jefferson, AR 72079-0502, USA
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Levi MS, Divine B, Hanig JP, Doerge DR, Vanlandingham MM, George NI, Twaddle NC, Bowyer JF. A comparison of methylphenidate-, amphetamine-, and methamphetamine-induced hyperthermia and neurotoxicity in male Sprague–Dawley rats during the waking (lights off) cycle. Neurotoxicol Teratol 2012; 34:253-62. [DOI: 10.1016/j.ntt.2012.01.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Revised: 01/12/2012] [Accepted: 01/14/2012] [Indexed: 10/14/2022]
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Zhang J, Hanig JP, De Felice AF. Biomarkers of endothelial cell activation: candidate markers for drug-induced vasculitis in patients or drug-induced vascular injury in animals. Vascul Pharmacol 2011; 56:14-25. [PMID: 21968053 DOI: 10.1016/j.vph.2011.09.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 08/26/2011] [Accepted: 09/12/2011] [Indexed: 01/08/2023]
Abstract
There is a pressing need for vascular biomarkers for studies of drug-induced vasculitis in patients and drug-induced vascular injury (DIVI) in animals. We previously reviewed a variety of candidate biomarkers of endothelial cell (EC) activation (Zhang et al., 2010). Now we update information on EC activation biomarkers from animal data on DIVI and clinical data of vasculitic patients, particularly patients with primary antineutrophil cytoplasmic autoantibody (ANCA)-associated small vessel vasculitis (primary AAVs), including Wegener's granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome and necrotizing crescentic glomerulonephritis. Drug-associated ANCA-positive small vessel vasculitis (drug-AAVs) can closely resemble primary AAVs, suggesting the large overlap between primary idiopathic systemic vasculitis and drug-induced vasculitis. AAVs in patients and DIVI in animals vary considerably; however, there is close resemblance between AAVs and DIVI in some respects: (1) the immunopathogenetic mechanisms (activation of primed neutrophils, ECs and T cells by ANCA in patients and activation of ECs, mast cells, and macrophages by drugs in animals); (2) the morphologic changes (fibrinoid necrosis of the vessel wall and neutrophilic infiltration); (3) the preferable sites (small arteries, arterioles, capillaries and venules); and (4) elevation of vascular biomarkers suggestive of an endothelial origin. The present review discusses soluble and cell component biomarkers and provides a rationale for the potential utility of EC activation biomarkers in nonclinical and clinical studies during new drug development. Further investigation, however, is needed to assess their potential utility.
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Affiliation(s)
- Jun Zhang
- Division of Drug Safety Research, Center for Drug Evaluation and Research, U. S. Food and Drug Administration, Silver Spring, MD 20993, USA.
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Zou X, Liu F, Zhang X, Patterson TA, Callicott R, Liu S, Hanig JP, Paule MG, Slikker W, Wang C. Inhalation anesthetic-induced neuronal damage in the developing rhesus monkey. Neurotoxicol Teratol 2011; 33:592-7. [DOI: 10.1016/j.ntt.2011.06.003] [Citation(s) in RCA: 120] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Revised: 05/24/2011] [Accepted: 06/08/2011] [Indexed: 10/18/2022]
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Knapton AD, Zhang J, Sistare FD, Hanig JP. The use of in situ perfusion of the rat mesentery as a model to investigate vascular injury directly induced by drugs. ACTA ACUST UNITED AC 2011; 32:489-97. [PMID: 21069100 DOI: 10.1358/mf.2010.32.7.1507854] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Exposure of the vasculature to vasodilators, pharmaceuticals and industrial chemicals may lead to injury of the blood vessel wall in animals. Vascular injury may begin with changes in the permeability of vascular endothelial cell and vessels, resulting in possible hemorrhage and edema leading subsequently to immune cell infiltration. The present study was undertaken to determine if the direct exposure of the Sprague Dawley rat mesenteric vasculature through the perfusion of aminophylline, fenoldopam, compound 48/80, histamine or serotonin has any such effects on the blood vessels, and if the two vital dyes Monastral blue B and Evans blue can be used to enhance the visualization of the vascular damage. Microscopic visualization was enhanced by the use of dyes and a variety of alterations of the perfused mesenteric vessels were detected, including varying degrees of mast cell degranulation, microvascular vasodilatation and increased vascular permeability. Macroscopic evidence of vascular damage was minimal. This study demonstrates that in situ perfusion of the rat mesentery is a simple and useful method to eliminate the influence of a variety of physiologic influences or homeostatic responses and can be used to further investigate drug-induced vascular damage.
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Affiliation(s)
- A D Knapton
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, FDA, Silver Spring, Maryland, USA
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Thomas M, George NI, Saini UT, Patterson TA, Hanig JP, Bowyer JF. Endoplasmic reticulum stress responses differ in meninges and associated vasculature, striatum, and parietal cortex after a neurotoxic amphetamine exposure. Synapse 2011; 64:579-93. [PMID: 20340164 DOI: 10.1002/syn.20763] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Amphetamine (AMPH) is used to treat attention deficit and hyperactivity disorders, but it can produce neurotoxicity and adverse vascular effects at high doses. The endoplasmic reticulum (ER) stress response (ERSR) entails the unfolded protein response, which helps to avoid or minimize ER dysfunction. ERSR is often associated with toxicities resulting from the accumulation of unfolded or misfolded proteins and has been associated with methamphetamine toxicity in the striatum. The present study evaluates the effect of AMPH on several ERSR elements in meninges and associated vasculature (MAV), parietal cortex, and striatum. Adult, male Sprague-Dawley rats were exposed to saline, environmentally induced hyperthermia (EIH) or four consecutive doses of AMPH that produce hyperthermia. Expression changes (mRNA and protein levels) of key ERSR-related genes in MAV, striatum, and parietal cortex at 3 h or 1 day postdosing were monitored. AMPH increased the expression of some ERSR-related genes in all tissues. Atf4 (activating transcription factor 4, an indicator of Perk pathway activation), Hspa5/Grp78 (Glucose regulated protein 78, master regulator of ERSR), Pdia4 (protein disulfide isomerase, protein-folding enzyme), and Nfkb1 (nuclear factor of kappa b, ERSR sensor) mRNA increased significantly in MAV and parietal cortex 3 h after AMPH. In striatum, Atf4 and Hspa5/Grp78 mRNA significantly increased 3 h after AMPH, but Pdia4 and Nfkb11 did not. Thus, AMPH caused a robust activation of the Perk pathway in all tissues, but significant Ire1 pathway activation occurred only after AMPH treatment in the parietal cortex and striatum. Ddit3/Chop, a downstream effector of the ERSR pathway related to the neurotoxicity, was only increased in striatum and parietal cortex. Conversely, Pdia4, an enzyme protective in the ERSR, was only increased in MAV. The overall ERSR manifestation varied significantly between MAV, striatum, and parietal cortex after a neurotoxic exposure to AMPH.
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Affiliation(s)
- Monzy Thomas
- National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079-9502, USA
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Zhang J, Defelice AF, Hanig JP, Colatsky T. Biomarkers of endothelial cell activation serve as potential surrogate markers for drug-induced vascular injury. Toxicol Pathol 2010; 38:856-71. [PMID: 20716788 DOI: 10.1177/0192623310378866] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Drug-induced vascular injury (DIVI) is a nonclinical finding that often confounds the toxicological evaluation of investigational drugs, but there is an absence of qualified biomarkers that can be used to detect and monitor its appearance in animals and patients during drug development and clinical use. It is well known that endothelial cell (EC) activation plays a key role in the expression and evolution of DIVI, and the various immunological and inflammatory factors involved in its expression may serve as potential biomarker candidates. Activated ECs change their morphology and gene expression, generating endothelial adhesion molecules, pro-coagulant molecules, cytokines, chemokines, vasodilators, nitric oxide, and acute-phase reactants. This review provides a brief historical background of EC activation and the search for biomarkers of early EC activation for monitoring DIVI. At present, no biomarkers of EC activation have been qualified to predict DIVI in the nonclinical or clinical context, and a robust pathologic foundation for their use is still lacking. We propose three categories of EC activation biomarkers: recommended surrogate markers, potentially useful markers, and emerging candidate markers. This review alerts pharmaceutical companies, research institutions, and regulatory agencies to the continuing need for reliable biomarkers of EC activation in drug development.
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Affiliation(s)
- Jun Zhang
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, USA.
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Liu F, Zou X, Sadovova N, Zhang X, Shi L, Guo L, Qian F, Wen Z, Patterson TA, Hanig JP, Paule MG, Slikker W, Wang C. Changes in gene expression after phencyclidine administration in developing rats: a potential animal model for schizophrenia. Int J Dev Neurosci 2010; 29:351-8. [PMID: 20691775 DOI: 10.1016/j.ijdevneu.2010.07.234] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Revised: 05/21/2010] [Accepted: 07/27/2010] [Indexed: 10/19/2022] Open
Abstract
Repeated administration of phencyclidine (PCP), an N-methyl-d-aspartate (NMDA) receptor antagonist, during development, may result in neuronal damage that leads to behavioral deficits in adulthood. The present study examined the potential neurotoxic effects of PCP exposure (10mg/kg) in rats on postnatal days (PNDs) 7, 9 and 11 and the possible underlying mechanism(s) for neurotoxicity. Brain tissue was harvested for RNA extraction and morphological assessments. RNA was collected from the frontal cortex for DNA microarray analysis and quantitative RT-PCR. Gene expression profiling was determined using Illumina Rat Ref-12 Expression BeadChips containing 22,226 probes. Based on criteria of a fold-change greater than 1.4 and a P-value less than 0.05, 19 genes including NMDAR1 (N-methyl-d-aspartate receptor) and four pro-apoptotic genes were up-regulated, and 25 genes including four anti-apoptotic genes were down-regulated, in the PCP-treated group. In addition, the schizophrenia-relevant genes, Bdnf (Brain-derived neurotrophic factor) and Bhlhb2 (basic helix-loop-helix domain containing, class B, 2), were significantly different between the PCP and the control groups. Quantitative RT-PCR confirmed the microarray results. Elevated neuronal cell death was further confirmed using Fluoro-Jade C staining. These findings support the hypothesis that neurodegeneration caused by PCP occurs, at least in part, through the up-regulation of NMDA receptors, which makes neurons possessing these receptors more vulnerable to endogenous glutamate. The changes in schizophrenia-relevant genes after repeated PCP exposure during development may provide important information concerning the validation of an animal model for this disorder.
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Affiliation(s)
- F Liu
- Division of Neurotoxicology, National Center for Toxicological Research/U.S. Food & Drug Administration, 3900 NCTR Road, Jefferson, AR 72079-9502, USA
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Slikker W, Shi Q, Guo L, Patterson TA, Dial S, Li Q, Sadovova N, Zhang X, Hanig JP, Paule MG, Wang C. Confirmation of the mode of action of anesthetic‐induced developmental neurotoxicity with gene expression studies. FASEB J 2010. [DOI: 10.1096/fasebj.24.1_supplement.761.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Qiang Shi
- Systems ToxicologyNCTR/FDAJeffersonAR
| | - Lei Guo
- Systems ToxicologyNCTR/FDAJeffersonAR
| | | | | | - Quan Li
- Microarray Core FacilityUTSW Medical CenterDallasTX
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Shi Q, Guo L, Patterson TA, Dial S, Li Q, Sadovova N, Zhang X, Hanig JP, Paule MG, Slikker W, Wang C. Gene expression profiling in the developing rat brain exposed to ketamine. Neuroscience 2010; 166:852-63. [PMID: 20080153 DOI: 10.1016/j.neuroscience.2010.01.007] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Revised: 01/04/2010] [Accepted: 01/05/2010] [Indexed: 12/31/2022]
Abstract
Ketamine, a non-competitive N-methyl-d-aspartate (NMDA) receptor antagonist, is associated with accelerated neuronal apoptosis in the developing rodent brain. In this study, postnatal day (PND) 7 rats were treated with 20 mg/kg ketamine or saline in six successive doses (s.c.) at 2-h intervals. Brain frontal cortical areas were collected 6 h after the last dose and RNA isolated and hybridized to Illumina Rat Ref-12 Expression BeadChips containing 22,226 probes. Many of the differentially expressed genes were associated with cell death or differentiation and receptor activity. Ingenuity Pathway Analysis software identified perturbations in NMDA-type glutamate, GABA and dopamine receptor signaling. Quantitative polymerase chain reaction (Q-PCR) confirmed that NMDA receptor subunits were significantly up-regulated. Up-regulation of NMDA receptor mRNA signaling was further confirmed by in situ hybridization. These observations support our working hypothesis that prolonged ketamine exposure produces up-regulation of NMDA receptors and subsequent over-stimulation of the glutamatergic system by endogenous glutamate, triggering enhanced apoptosis in developing neurons.
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Affiliation(s)
- Q Shi
- Division of Systems Toxicology, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079, USA
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Zhang X, Paule MG, Newport GD, Zou X, Sadovova N, Berridge MS, Apana SM, Hanig JP, Slikker W, Wang C. A minimally invasive, translational biomarker of ketamine-induced neuronal death in rats: microPET Imaging using 18F-annexin V. Toxicol Sci 2009; 111:355-61. [PMID: 19638431 DOI: 10.1093/toxsci/kfp167] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
It has been reported that suppression of N-methyl-D-aspartate (NMDA) receptor function by ketamine may trigger apoptosis of neurons when given repeatedly during the brain growth spurt period. Because microPET scans can provide in vivo molecular imaging at sufficient resolution, it has been proposed as a minimally invasive method for detecting apoptosis using the tracer (18)F-labeled annexin V. In this study, the effect of ketamine on the metabolism and integrity of the rat brain were evaluated by investigating the uptake and retention of (18)F-fluorodeoxyglucose (FDG) and (18)F-annexin V using microPET imaging. On postnatal day (PND) 7, rat pups in the experimental group were exposed to six injections of ketamine (20 mg/kg at 2-h intervals) and control rat pups received six injections of saline. On PND 35, 37 MBq (1 mCi) of (18)F-FDG or (18)F-annexin V was injected into the tail vein of treated and control rats, and static microPET images were obtained over 1 (FDG) and 2 h (annexin V) following the injection. No significant difference was found in (18)F-FDG uptake in the regions of interest (ROIs) in the brains of ketamine-treated rats compared with saline-treated controls. The uptake of (18)F-annexin V, however, was significantly increased in the ROI of ketamine-treated rats. Additionally, the duration of annexin V tracer washout was prolonged in the ketamine-treated animals. These results demonstrate that microPET imaging is capable of distinguishing differences in retention of (18)F-annexin V in different brain regions and suggests that this approach may provide a minimally invasive biomarker of neuronal apoptosis in rats.
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Affiliation(s)
- Xuan Zhang
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079, USA
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Zou X, Patterson TA, Divine RL, Sadovova N, Zhang X, Hanig JP, Paule MG, Slikker W, Wang C. Prolonged exposure to ketamine increases neurodegeneration in the developing monkey brain. Int J Dev Neurosci 2009; 27:727-31. [PMID: 19580862 DOI: 10.1016/j.ijdevneu.2009.06.010] [Citation(s) in RCA: 172] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Revised: 06/12/2009] [Accepted: 06/26/2009] [Indexed: 11/26/2022] Open
Abstract
Ketamine, a widely used pediatric anesthetic, has been associated with enhanced neuronal toxicity in the developing brain, but mechanisms and neuronal susceptibility to neurotoxic insult leading to neuronal cell death remain poorly defined. One of the main goals of this study was to determine whether there is a duration of ketamine-induced anesthesia below which no significant ketamine-induced neurodegeneration can be detected. Newborn rhesus monkeys (postnatal day 5 or 6) were administered ketamine intravenously for 3, 9 or 24h to maintain a steady anesthetic plane, followed by a 6-h withdrawal period. The 9- and 24-h durations were selected as relatively long and extremely long exposures, respectively, while the 3-h treatment more closely approximates a typical duration of pediatric general anesthesia. Animals were subsequently perfused under anesthesia and brain tissue was processed for analyses using silver and Fluoro-Jade C stains and caspase-3 immunostain. The results indicated that no significant neurotoxic effects occurred if the anesthesia duration was 3h. However, ketamine infusions for either 9 or 24h significantly increased neuronal cell death in layers II and III of the frontal cortex. Although a few caspase-3- and Fluoro-Jade C-positive neuronal profiles were observed in some additional brain areas including the hippocampus, thalamus, striatum and amygdala, no significant differences were detected between ketamine-treated and control monkeys in these areas after 3, 9 or 24h of exposure. These data show that treatment with ketamine up to 3h is without adverse effects as determined by nerve cell death. However, anesthetic durations of 9h or greater are associated with significant brain cell death in the frontal cortex. Thus, the threshold duration below which no neurotoxicity would be expected is somewhere between 3 and 9h.
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Affiliation(s)
- Xiaoju Zou
- Division of Neurotoxicology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
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Zhang J, Goering PL, Espandiari P, Shaw M, Bonventre JV, Vaidya VS, Brown RP, Keenan J, Kilty CG, Sadrieh N, Hanig JP. Differences in immunolocalization of Kim-1, RPA-1, and RPA-2 in kidneys of gentamicin-, cisplatin-, and valproic acid-treated rats: potential role of iNOS and nitrotyrosine. Toxicol Pathol 2009; 37:629-43. [PMID: 19535489 DOI: 10.1177/0192623309339605] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The present study compared the immunolocalization of Kim-1, renal papillary antigen (RPA)-1, and RPA-2 with that of inducible nitric oxide synthase (iNOS) and nitrotyrosine in kidneys of gentamicin sulfate (Gen)- and cisplatin (Cis)-treated rats. The specificity of acute kidney injury (AKI) biomarkers, iNOS, and nitrotyrosine was evaluated by dosing rats with valproic acid (VPA). Sprague-Dawley (SD) rats were injected subcutaneously (sc) with 100 mg/kg/day of Gen for six or fourteen days; a single intraperitoneal (ip) dose of 1, 3, or 6 mg/kg of Cis; or 650 mg/kg/day of VPA (ip) for four days. In Gen-treated rats, Kim-1 was expressed in the epithelial cells, mainly in the S1/S2 segments but less so in the S3 segment, and RPA-1 was increased in the epithelial cells of collecting ducts (CD) in the cortex. Spatial expression of iNOS or nitrotyrosine with Kim-1 or RPA-1 was detected. In Cis-treated rats, Kim-1 was expressed only in the S3 segment cells, and RPA-1 and RPA-2 were increased in the epithelial cells of medullary CD or medullary loop of Henle (LH), respectively. Spatial expression of iNOS or nitrotyrosine with RPA-1 or RPA-2 was also identified. These findings suggest that peroxynitrite formation may be involved in the pathogenesis of Gen and Cis nephrotoxicity and that Kim-1, RPA-1, and RPA-2 have the potential to serve as site-specific biomarkers for Gen or Cis AKI.
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Affiliation(s)
- Jun Zhang
- Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993-0002, USA.
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Zou X, Patterson TA, Sadovova N, Twaddle NC, Doerge DR, Zhang X, Fu X, Hanig JP, Paule MG, Slikker W, Wang C. Potential neurotoxicity of ketamine in the developing rat brain. Toxicol Sci 2009; 108:149-58. [PMID: 19126600 DOI: 10.1093/toxsci/kfn270] [Citation(s) in RCA: 150] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Ketamine, an N-methyl-D-aspartate (NMDA) receptor ion channel blocker, is a widely used anesthetic recently reported to enhance neuronal death in developing rodents and nonhuman primates. This study evaluated dose-response and time-course effects of ketamine, levels of ketamine in plasma and brain, and the relationship between altered NMDA receptor expression and ketamine-induced neuronal cell death during development. Postnatal day 7 rats were administered 5, 10, or 20 mg/kg ketamine using single or multiple injections (subcutaneously) at 2-h intervals, and the potential neurotoxic effects were examined 6 h after the last injection. No significant neurotoxic effects were detected in layers II or III of the frontal cortex of rats administered one, three, or six injections of 5 or 10 mg/kg ketamine. However, in rats administered six injections of 20 mg/kg ketamine, a significant increase in the number of caspase-3- and Fluoro-Jade C-positive neuronal cells was observed in the frontal cortex. Electron microscopic observations showed typical nuclear condensation and fragmentation indicating enhanced apoptotic characteristics. Increased cell death was also apparent in other brain regions. In addition, apoptosis occurred after plasma and brain levels of ketamine had returned to baseline levels. In situ hybridization also showed a remarkable increase in mRNA signals for the NMDA NR1 subunit in the frontal cortex. These data demonstrate that ketamine administration results in a dose-related and exposure-time dependent increase in neuronal cell death during development. Ketamine-induced cell death appears to be apoptotic in nature and closely associated with enhanced NMDA receptor subunit mRNA expression.
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Affiliation(s)
- Xiaoju Zou
- Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food & Drug Administration, Jefferson, Arkansas 72079, USA
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Miller TJ, Knapton A, Adeyemo O, Noory L, Weaver J, Hanig JP. Cytochrome c: a non-invasive biomarker of drug-induced liver injury. J Appl Toxicol 2008; 28:815-28. [PMID: 18418843 DOI: 10.1002/jat.1347] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Limitations of existing biomarkers to detect liver injury in experimental animals highlight the need for additional tools to predict human toxicity. The utility of cytochrome c (cyt c) as a biomarker in serum and urine was evaluated in two rodent liver injury models. Adult Sprague-Dawley rats treated with acetaminophen or D-galactosamine (GalN) showed dose- and time-dependent histomorphological changes and TUNEL staining in liver consistent with hepatocellular necrosis, apoptosis and inflammation up to 72 h. Matching changes in serum alanine transaminase (ALT), aspartate transaminase (AST) and cyt c peaked at 24 h for either drug at the highest dose, cyt c falling rapidly at 48 hours with ALT and AST remained high. Intracellular transit of cyt c from mitochondria to the cytoplasm in damaged hepatocytes, and then to peripheral circulation, was observed by immunohistochemistry. Correlation coefficients between cyt c and serum diagnostic tests indicate the liver to be the primary source of cyt c. Urinary analysis for cyt c revealed time-dependent increase at 6 h, peaking at 24 h in GalN-treated rats in contrast with irregular patterns of urinary ALT and AST activity. Histological changes detected at 6 h preceded altered ALT, AST and cyt c at 12 and 18 h, respectively, in GalN-treated rats. These studies demonstrate cyt c to be a useful indicator of hepatic injury in rodents and support its utility as a non-invasive predictor of drug-induced hepatotoxicity, when utilized as a potential urinary biomarker.
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Affiliation(s)
- T J Miller
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA.
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Zhang J, Snyder RD, Herman EH, Knapton A, Honchel R, Miller T, Espandiari P, Goodsaid FM, Rosenblum IY, Hanig JP, Sistare FD, Weaver JL. Histopathology of vascular injury in Sprague-Dawley rats treated with phosphodiesterase IV inhibitor SCH 351591 or SCH 534385. Toxicol Pathol 2008; 36:827-39. [PMID: 18776163 DOI: 10.1177/0192623308322308] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Histopathological and immunohistochemical studies were conducted to characterize vascular injuries in rats treated with phosphodiesterase (PDE) IV inhibitors SCH 351591 or SCH 534385. Sprague-Dawley rats were administered PDE IV inhibitors by gavage at a range of doses and times. The two PDE IV inhibitors induced comparable levels of vascular injury, primarily in the mesentery and to a lesser extent in the pancreas, kidney, liver, small intestine, and stomach. Mesenteric vascular changes occurred as early as one hour, progressively developed over twenty-four to forty-eight hours, peaked at seventy-two hours, and gradually subsided from seven to nine days. The typical morphology of the vascular toxicity consisted of hemorrhage and necrosis of arterioles and arteries, microvascular injury, fibrin deposition, and perivascular inflammation of a variety of blood vessels. The incidence and severity of mesenteric vascular injury increased in a time- and dose-dependent manner in SCH 351591- or SCH 534385-treated rats. Mesenteric vascular injury was frequently associated with activation of mast cells (MC), endothelial cells (EC), and macrophages (MØ). Immunohistochemical studies showed increases in CD63 immunoreactivity of mesenteric MC and in nitrotyrosine immunoreactivity of mesenteric EC and MØ. The present study also provides a morphological and cellular basis for evaluating candidate biomarkers of drug-induced vascular injury.
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Affiliation(s)
- Jun Zhang
- Division of Applied Pharmacology Research (HFD-910), Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993-0002, USA.
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Espandiari P, Zhang J, Schnackenberg LK, Miller TJ, Knapton A, Herman EH, Beger RD, Hanig JP. Age‐related differences in susceptibility to toxic effects of valproic acid in rats. J Appl Toxicol 2008; 28:628-37. [DOI: 10.1002/jat.1314] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Wang C, Sadovova N, Patterson TA, Zou X, Fu X, Hanig JP, Paule MG, Ali SF, Zhang X, Slikker W. Protective effects of 7-nitroindazole on ketamine-induced neurotoxicity in rat forebrain culture. Neurotoxicology 2008; 29:613-20. [DOI: 10.1016/j.neuro.2008.03.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2008] [Revised: 02/29/2008] [Accepted: 03/14/2008] [Indexed: 10/22/2022]
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Miller TJ, Honchel R, Espandiari P, Knapton A, Zhang J, Sistare FD, Hanig JP. The utility of the K6/ODC transgenic mouse as an alternative short term dermal model for carcinogenicity testing of pharmaceuticals. Regul Toxicol Pharmacol 2007; 50:87-97. [PMID: 18069108 DOI: 10.1016/j.yrtph.2007.10.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2007] [Revised: 10/16/2007] [Accepted: 10/17/2007] [Indexed: 11/19/2022]
Abstract
The use of transgenic rodents may overcome many limitations of traditional cancer studies. Regulatory perspectives continue to evolve as new models are developed and validated. The transgenic mouse, K6/ODC, develops epidermal tumors when exposed to genotoxic carcinogens. In this study, K6/ODC mice were evaluated for model fitness and health robustness in a 36-week study to determine oncogenic risk of residual DNA in vaccines from neoplastic cell substrates. K6/ODC and C57BL/6 mice were treated with T24-H-ras expression plasmid, carrier vector DNA, or saline topically or by subcutaneous injection. One group of K6/ODC mice received 7,12-dimethylbenz-[a]anthracene [DMBA] dermally. Only DMBA-treated mice developed papillomas by six weeks, increasing in incidence to 25 weeks. By week 11, many K6/ODC mice showed severe dehydration and dermal eczema. By week 32, (6/8) surviving K6/ODC mice showed loss of mobility and balance. Microscopic evaluation of tissues revealed dermal/sebaceous gland hyperplasia, follicular dystrophy, splenic atrophy, and amyloid deposition/neutrophilic infiltration within liver, heart, and spleen, in all K6/ODC mice. Pathology was not detected in C57BL/6 mice. Progressive adverse health, decreased survival, and failure to develop papillomas to the H-ras plasmid suggest that K6/ODC mice may be an inappropriate alternative model for detection of oncogenic DNA and pharmaceutical carcinogenicity testing.
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Affiliation(s)
- T J Miller
- Division of Applied Pharmacology Research, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993-0002, USA.
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