Figure 6.

Ketone bodies suppress phenylephrine-induced cardiomyocyte growth through inhibition of mTOR. (A and B) Representative immunoblots of cardiomyocyte lysates (A) and the densitometry analyses, normalized by α-sarcomeric actinin (n = 6) (B). (C and D) Representative immunoblots of phosphorylated p70S6K in cardiomyocytes transduced with either Rheb-expressing adenovirus or LacZ-expressing adenovirus (C) and the densitometry analyses relative to total p70S6K expression (n = 6) (D). (E and F) Phalloidin staining of cardiomyocytes treated with the indicated adenovirus, followed by incubation with PE or vehicle in the presence or absence of ketone bodies for 24 h (Keto, cocktail of β-OHB and AcAc, 1 mM and 500 µM each). One-way ANOVA with Tukey post hoc test was performed (n = 5). Error bars indicate SEM. *P < 0.05, **P < 0.001.