Fig. 5

GRK2 downregulation keeps active the PKA/CREB and AMPK pathways and promotes higher levels of PGC1 and mitochondrial fusion markers in cardiac tissue after long-lasting HFD-feeding. a Expression of the PPARγ coactivator 1-alpha (ppargc1α), beta (ppargc1β) and of PPARα were quantified by qPCR and normalized by a geometrical mean of HPRT and RPS29 (N = 5–6 animals per genotype and condition). b Densitometric analysis and representative blots of total and phospho-PKA (Thr197); total and phospho-CREB (Ser133) and total and phospho-AMPK (Thr172) in WT and GRK2+/− mice after 30 weeks of HFD (N = 5–6). c MFN1 and OPA1 protein levels were analyzed in cardiac tissue of the same animals. Graphs display the MFN1 data normalized by Nucleolin levels or the calculated L-OPA1 vs S-OPA1 ratio (N = 5–7). Data are mean ± SEM and are expressed as fold-change over wild type HFD conditions. Statistical analysis was performed by two-tail unpaired Student’s t test. *P < 0.05, **P < 0.01, ***P < 0.001