Liver biomarker and in vitro assessment confirm the hepatic origin of aminotransferase elevations lacking histopathological correlate in beagle dogs treated with GABAA receptor antagonist NP260
Autor: | Stephen Wanaski, Stephen M. Collins, Edward L. LeCluyse, Alison H. Harrill, Paul B. Watkins, John M. Cullen, Lakshmi Ramanathan, Yu Ho, Kelly Rose, John S. Eaddy |
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Rok vydání: | 2013 |
Předmět: |
Genetic Markers
Male medicine.medical_specialty L-Iditol 2-Dehydrogenase Necrosis Time Factors Sorbitol dehydrogenase Pharmacology Biology Toxicology Risk Assessment Rats Sprague-Dawley Adenosine Triphosphate Dogs Glutamate Dehydrogenase Species Specificity Predictive Value of Tests Internal medicine Toxicity Tests medicine MiR-122 Animals Humans GABA-A Receptor Antagonists Sulfones Cells Cultured GABAA receptor Glutamate dehydrogenase Antagonist Alanine Transaminase Clinical Enzyme Tests meta-Aminobenzoates Rats MicroRNAs Endocrinology Liver Toxicity Hepatocytes Biomarker (medicine) Female medicine.symptom Chemical and Drug Induced Liver Injury Biomarkers |
Zdroj: | Toxicology and applied pharmacology. 277(2) |
ISSN: | 1096-0333 |
Popis: | NP260 was designed as a first-in-class selective antagonist of α4-subtype GABAA receptors that had promising efficacy in animal models of pain, epilepsy, psychosis, and anxiety. However, development of NP260 was complicated following a 28-day safety study in dogs in which pronounced elevations of serum aminotransferase levels were observed, although there was no accompanying histopathological indication of hepatocellular injury. To further investigate the liver effects of NP260, we assayed stored serum samples from the 28-day dog study for liver specific miRNA (miR-122) as well as enzymatic biomarkers glutamate dehydrogenase and sorbitol dehydrogenase, which indicate liver necrosis. Cytotoxicity assessments were conducted in hepatocytes derived from dog, rat, and human liver samples to address the species specificity of the liver response to NP260. All biomarkers, except ALT, returned toward baseline by Day 29 despite continued drug treatment, suggesting adaptation to the initial injury. In vitro analysis of the toxicity potential of NP260 to primary hepatocytes indicated a relative sensitivity of dog>human>rat, which may explain, in part, why the liver effects were not evident in the rodent safety studies. Taken together, the data indicate that a diagnostic biomarker approach, coupled with sensitive in vitro screening strategies, may facilitate interpretation of toxicity potential when an adaptive event masks the underlying toxicity. |
Databáze: | OpenAIRE |
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