Figure 4.

PCA promotes the nuclear localization of PKM2. Primary neonatal rat ventricular myocytes (NRVMs) were exposed to 1% O₂ in glucose-free DMEM (OGD) for 4 h in the presence of protocatechuic aldehyde (PCA). (A) PKM2 activity in NRVMs (n = 6). (B) Immunofluorescence image of endogenous PKM2 (one of three independent experiments. Scale bar: 10 μm. (C) Nuclear PKM2 protein expression (n = 3). (D) Cytoplasmic PKM2 protein expression (n = 3). (E) Total PKM2 protein expression (n = 3). (F) Docking analysis illustrates the interaction between PCA and PKM2. The residues that are likely to participate in the interactions with PCA are labeled. (G) Representative co-immunoprecipitation (co-IP) analysis of PKM2 and SIRT6 in the NRVMs (n = 3). (H) Representative co-IP of PKM2 and β-catenin in the NRVMs (n = 3). Results are shown as mean ± SD; ∗P < 0.05, ∗∗P < 0.01, ∗∗∗P < 0.001.