Fig. 1.

H1N1 infection induces glycolysis in vivo and in vitro. A A549 cells were mock infected or infected with H1N1 at an MOI of 1, and cells were harvested at 8, 16, and 24 h p.i.. The expression of HK2, PKM2, and PDK3 was analyzed by Western blotting. B A549 cells were mock infected or infected with H1N1 at an MOI of 1. Cells were harvested at 24 h p.i., and intracellular ATP levels were measured. C–E Mice were intranasally administered H1N1 (A/PR/8/34) 800 PFU/mouse or mock infected as controls (n = 3 mice/group). At 3 d p.i., the expression of HK2, PKM2, and PDK3 in mouse lung tissues was measured by western blotting (C) (the lower bands in PDK3 are nonspecific). Serum lactate (D) and lactate in lung tissue homogenate (E) were measured by a lactate assay kit. M, mock infection. ns, not significant. *P < 0.05, **P < 0.01, ***P < 0.001.