FIGURE 7.

Impact of PCSK9 on CTPR9-induced effects on glucose metabolism. Adult rat cardiomyocytes were incubated in the presence of LacZ-containing supernatant (control), murine wild-type PCSK9 or GOF PCSK9 (each 0.5 μg/ml) in serum-free medium for 24 h and subsequently treated with CTRP9 (4 μg/ml) for the indicated times. (A) Phosphorylation of Akt and AS160 was analyzed after 20 min CTRP9 stimulation by Western Blotting. Representative Western blots and densitometry of protein data are shown. Total Akt and total AS160 as well as GAPDH served as a loading control. (B) Translocation of GLUT-4 from the cytosol to the plasma membrane was analyzed after 30 min CTRP9 stimulation. Representative Western blots and densitometry of protein data are shown. Na-K-ATPase served as a marker for membrane fraction and GAPDH as a marker for the cytosol. (C) Glucose uptake was measured after 10 min stimulation with CTRP9. (D) Changes in GLUT-4, hexokinase and PFK1 mRNA expression after 24 h stimulation with CTRP9 were analyzed by Real-time PCR. All data are mean ± SEM, 4 independent experiments, n = 8 per group, *p < 0.05.