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Browsing by Author "Pandey, Ravi"
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Item A novel systems biology approach to evaluate mouse models of late-onset Alzheimer’s disease(BMC, 2020-11-10) Preuss, Christoph; Pandey, Ravi; Piazza, Erin; Fine, Alexander; Uyar, Asli; Perumal, Thanneer; Garceau, Dylan; Kotredes, Kevin P.; Williams, Harriet; Mangravite, Lara M.; Lamb, Bruce T.; Oblak, Adrian L.; Howell, Gareth R.; Sasner, Michael; Logsdon, Benjamin A.; Carter, Gregory W.; Psychiatry, School of MedicineBackground Late-onset Alzheimer’s disease (LOAD) is the most common form of dementia worldwide. To date, animal models of Alzheimer’s have focused on rare familial mutations, due to a lack of frank neuropathology from models based on common disease genes. Recent multi-cohort studies of postmortem human brain transcriptomes have identified a set of 30 gene co-expression modules associated with LOAD, providing a molecular catalog of relevant endophenotypes. Results This resource enables precise gene-based alignment between new animal models and human molecular signatures of disease. Here, we describe a new resource to efficiently screen mouse models for LOAD relevance. A new NanoString nCounter® Mouse AD panel was designed to correlate key human disease processes and pathways with mRNA from mouse brains. Analysis of the 5xFAD mouse, a widely used amyloid pathology model, and three mouse models based on LOAD genetics carrying APOE4 and TREM2*R47H alleles demonstrated overlaps with distinct human AD modules that, in turn, were functionally enriched in key disease-associated pathways. Comprehensive comparison with full transcriptome data from same-sample RNA-Seq showed strong correlation between gene expression changes independent of experimental platform. Conclusions Taken together, we show that the nCounter Mouse AD panel offers a rapid, cost-effective and highly reproducible approach to assess disease relevance of potential LOAD mouse models. Supplementary information Supplementary information accompanies this paper at 10.1186/s13024-020-00412-5.Item Pharmacokinetic, pharmacodynamic, and transcriptomic analysis of chronic levetiracetam treatment in 5XFAD mice: A MODEL-AD preclinical testing core study(Wiley, 2022-08-23) Onos, Kristen D.; Quinney, Sara K.; Jones, David R.; Masters, Andrea R.; Pandey, Ravi; Keezer, Kelly J.; Biesdorf, Carla; Metzger, Ingrid F.; Meyers, Jill A.; Peters, Johnathon; Persohn, Scott C.; McCarthy, Brian P.; Bedwell, Amanda A.; Figueiredo, Lucas L.; Cope, Zackary A.; Sasner, Michael; Howell, Gareth R.; Williams, Harriet M.; Oblak, Adrian L.; Lamb, Bruce T.; Carter, Gregory W.; Sukoff Rizzo, Stacey J.; Territo, Paul R.; Obstetrics and Gynecology, School of MedicineIntroduction: Hyperexcitability and epileptiform activity are commonplace in Alzheimer's disease (AD) patients and associated with impaired cognitive function. The anti-seizure drug levetiracetam (LEV) is currently being evaluated in clinical trials for ability to reduce epileptiform activity and improve cognitive function in AD. The purpose of our studies was to establish a pharmacokinetic/pharmacodynamic (PK/PD) relationship with LEV in an amyloidogenic mouse model of AD to enable predictive preclinical to clinical translation, using the rigorous preclinical testing pipeline of the Model Organism Development and Evaluation for Late-Onset Alzheimer's Disease Preclinical Testing Core. Methods: A multi-tier approach was applied that included quality assurance and quality control of the active pharmaceutical ingredient, PK/PD modeling, positron emission tomography/magnetic resonance imaging (PET/MRI), functional outcomes, and transcriptomics. 5XFAD mice were treated chronically with LEV for 3 months at doses in line with those allometrically scaled to the clinical dose range. Results: Pharmacokinetics of LEV demonstrated sex differences in Cmax, AUC0-∞, and CL/F, and a dose dependence in AUC0-∞. After chronic dosing at 10, 30, 56 mg/kg, PET/MRI tracer 18F-AV45, and 18F-fluorodeoxyglucose (18F-FDG) showed specific regional differences with treatment. LEV did not significantly improve cognitive outcomes. Transcriptomics performed by nanoString demonstrated drug- and dose-related changes in gene expression relevant to human brain regions and pathways congruent with changes in 18F-FDG uptake. Discussion: This study represents the first report of PK/PD assessment of LEV in 5XFAD mice. Overall, these results highlighted non-linear kinetics based on dose and sex. Plasma concentrations of the 10 mg/kg dose in 5XFAD overlapped with human plasma concentrations used for studies of mild cognitive impairment, while the 30 and 56 mg/kg doses were reflective of doses used to treat seizure activity. Post-treatment gene expression analysis demonstrated LEV dose-related changes in immune function and neuronal-signaling pathways relevant to human AD, and aligned with regional 18F-FDG uptake. Overall, this study highlights the importance of PK/PD relationships in preclinical studies to inform clinical study design. Highlights: Significant sex differences in pharmacokinetics of levetiracetam were observed in 5XFAD mice. Plasma concentrations of 10 mg/kg levetiracetam dose in 5XFAD overlapped with human plasma concentration used in the clinic. Drug- and dose-related differences in gene expression relevant to human brain regions and pathways were also similar to brain region-specific changes in 18F-fluorodeoxyglucose uptake.