Logo image
In vitro Cytotoxicity and Pharmacokinetic Evaluation of Pharmacological Ascorbate in Dogs
Journal article   Open access   Peer reviewed

In vitro Cytotoxicity and Pharmacokinetic Evaluation of Pharmacological Ascorbate in Dogs

Margaret L. Musser, Alyssa L. Mahaffey, Melissa A. Fath, Garry R. Buettner, Brett A. Wagner, Benjamin K. Schneider, Yeon-Jung Seo, Jonathan P. Mochel and Chad M. Johannes
Frontiers in veterinary science, Vol.6, pp.385-385
11/07/2019
DOI: 10.3389/fvets.2019.00385
PMCID: PMC6854015
PMID: 31788483
url
https://doi.org/10.3389/fvets.2019.00385View
Published (Version of record) Open Access

Abstract

Background: High-dose, pharmacological ascorbate (P-AscH(-)) is preferentially cytotoxic to human cancer cells in vitro. Investigations on the efficacy of P-AscH(-) as an adjuvant treatment for multiple human cancers are on-going, but has yet to be formally investigated in dogs. The primary objectives of this study were to determine the pharmacokinetic (PK) profile of P-AscH(-) in healthy Beagle dogs and the effects of P-AscH(-) on canine osteosarcoma cells in vitro. Methods: Eight purpose-bred, healthy, spayed female Beagle dogs, between 20 and 21 months old, and 8-10 kg were administered two doses of P-AscH(-) (550 or 2,200 mg/kg) via intravenous infusion over 6 h, on separate days. Plasma ascorbate concentrations were measured at 12 time points during and after infusion for PK analysis using nonlinear mixed-effects (NAME) and non-compartmental analysis (NCA). Clonogenic assays were performed on 2 canine osteosarcoma cell lines (D-17 and OSCA-8) and canine primary dermal fibroblasts after exposure to high concentrations of ascorbate (75 pmoles/cell). Results: Plasma ascorbate levels in the dogs peaked at approximately 10 mM following 2,200 mg/kg and returned to baseline 6-8 h after dosing. Minor adverse effects were seen in two dogs. Ascorbate (75 prnoles/cell) significantly decreased survival in both the osteosarcoma cell lines (D-17 63% SD 0.010, P = 0.005; OSCA-8 50% SD 0.086, P = 0.026), compared to normal fibroblasts (27% SD 0.056). Conclusions: Pharmacological ascorbate is preferentially cytotoxic to canine-derived cancer cells. High levels of ascorbate can be safely administered to dogs. Further studies are needed to determine the effects of P-AscH(-) on canine patients.
Life Sciences & Biomedicine Science & Technology Veterinary Sciences

Details

Logo image