Fig. 4.

Pyruvate oxidation decreases viral replication via induction of TCA cycle. Cells were infected by MHV (MOI 0.05) for 24 h. Metabolite and chemicals were treated after serum free medium is changed to FBS containing medium. A, E, F RNA expression of MHV in cells treated with pyruvate, pyruvate oxidation inhibitor (CPI-613), and pyruvate oxidation activator (Dichloroacetate, DCA) in replete medium (glucose 450 mg/dl, pyruvate 0.5 mM). Rplp0 was used for an internal control. B, G Western blot analysis and quantification of SPIKE in cells treated with pyruvate and pyruvate oxidation activator in replete medium (glucose 450 mg/dl, pyruvate 0.5 mM). β-actin was used for an internal control. C, H Viability of cells incubated for 24 h with medium collected from MHV-infected cells which were treated as indicated. D, I Infectious virus titer (Log₁₀PFU/ml) measured by plaque forming assay. J Illustration of metabolic intervention induced by pyruvate and pyruvate oxidation. Values represent means ± SD. *p < 0.05 vs. vehicle. #p < 0.05 vs. pyruvate. One-way ANOVA followed by a tukey’s multiple comparison test. All experiments were repeated at least 3 times