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Obesity impairs host defense against Klebsiella pneumoniae, but responsible mechanisms are incompletely understood. To determine the impact of diet-induced obesity on pulmonary host defense against K. pneumoniae, we fed 6-wk-old male C57BL/6j mice a normal diet (ND) or high-fat diet (HFD) (13% vs. 60% fat, respectively) for 16 wk. Mice were intratracheally infected with Klebsiella, assayed at 24 or 48 h for bacterial colony-forming units, lung cytokines, and leukocytes from alveolar spaces, lung parenchyma, and gonadal adipose tissue were assessed using flow cytometry. Neutrophils from uninfected mice were cultured with and without 2-deoxy-d-glucose (2-DG) and assessed for phagocytosis, killing, reactive oxygen intermediates (ROI), transport of 2-DG, and glucose transporter (GLUT1–4) transcripts, and protein expression of GLUT1 and GLUT3. HFD mice had higher lung and splenic bacterial burdens. In HFD mice, baseline lung homogenate concentrations of IL-1β, IL-6, IL-17, IFN-γ, CXCL2, and TNF-α were reduced relative to ND mice, but following infection were greater for IL-6, CCL2, CXCL2, and IL-1β (24 h only). Despite equivalent lung homogenate leukocytes, HFD mice had fewer intraalveolar neutrophils. HFD neutrophils exhibited decreased Klebsiella phagocytosis and killing and reduced ROI to heat-killed Klebsiella in vitro. 2-DG transport was lower in HFD neutrophils, with reduced GLUT1 and GLUT3 transcripts and protein (GLUT3 only). Blocking glycolysis with 2-DG impaired bacterial killing and ROI production in neutrophils from mice fed ND but not HFD. Diet-induced obesity impairs pulmonary Klebsiella clearance and augments blood dissemination by reducing neutrophil killing and ROI due to impaired glucose transport.

Aim: High-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. Methods: After 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. Results: The 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 ​

Introduction: High-dose valproic acid (VPA) has been shown to improve the survival and neurologic outcomes in preclinical brain injury models including asphyxial cardiac arrest (CA) in rats. However, its pharmacokinetics, pharmacodynamics, and safety profiles in large animal CA models are unknown. Hypothesis: High-dose VPA can be safely administered after return of spontaneous circulation (ROSC) and cross the blood-brain barrier dose-dependently in a swine CA model. Methods: After 8 minutes of untreated ventricular fibrillation CA, male Yorkshire swine [43.3 (3.0) kg] were resuscitated for up to 16 minutes until ROSC. They were randomized to receive placebo, 75 mg/kg, 150 mg/kg, or 300 mg/kg VPA as 90-minute intravenous infusion (n=5 per group) beginning 20 minutes after sustained ROSC. Animals were monitored for 2 additional hours after infusion ended and then euthanized. Experimental operators were blinded to the treatments. Results: The mean total cardiac arrest duration was 15.0 (1.6) minutes, with no significant differences between groups. At end of infusion, the serum free VPA concentration increased dose dependently, from 139.2 (10.1) mcg/mL [75 mg/kg VPA] to 287.2 (24.6) mcg/mL [150 mg/kg VPA] to 565.6 (36.5) mcg/mL [300 mg/kg VPA] (p2 =0.98). All animals survived until euthanasia, although the 300 mg/kg group required more epinephrine to maintain mean arterial pressure greater than or equal to 80 mmHg and had higher lactic acidosis. Conclusion: Brain VPA concentrations correlate strongly with serum free VPA when high-dose intravenous VPA is given after ROSC in a swine CA model. These results provide the foundation for dose-optimization studies of high-dose VPA as a neuroprotective therapy following resuscitation from CA.