Abstract
AimHigh-dose valproic acid (VPA) improves the survival and neurologic outcomes after asphyxial cardiac arrest (CA) in rats. We characterized the pharmacokinetics, pharmacodynamics, and safety of high-dose VPA in a swine CA model to advance clinical translation. MethodsAfter 8 min of untreated ventricular fibrillation CA, 20 male Yorkshire swine were resuscitated until return of spontaneous circulation (ROSC). They were block randomized to receive placebo, 75 mg/kg, 150 mg/kg, or 300 mg/kg VPA as 90-min intravenous infusion (n = 5/group) beginning at ROSC. Animals were monitored for 2 additional hours then euthanized. Experimental operators were blinded to treatments. ResultsThe mean(SD) total CA duration was 14.8(1.2) minutes. 300 mg/kg VPA animals required more adrenaline to maintain mean arterial pressure ≥80 mmHg and had worse lactic acidosis. There was a strong linear correlation between plasma free VPA Cmax and brain total VPA (r2 = 0.9494; p < 0.0001). VPA induced dose-dependent increases in pan- and site-specific histone H3 and H4 acetylation in the brain. Plasma free VPA Cmax is a better predictor than peripheral blood mononuclear cell histone acetylation for brain H3 and H4 acetylation (r2 = 0.7189 for H3K27ac, r2 = 0.7189 for pan-H3ac, and r2 = 0.7554 for pan-H4ac; p < 0.0001). ConclusionsUp to 150 mg/kg VPA can be safely tolerated as 90-min intravenous infusion in a swine CA model. High-dose VPA induced dose-dependent increases in brain histone H3 and H4 acetylation, which can be predicted by plasma free VPA Cmax as the pharmacodynamics biomarker for VPA target engagement after CA.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have