Ketone Body β-Hydroxybutyrate Prevents Myocardial Oxidative Stress in Septic Cardiomyopathy

Figure 5

The ketone bodies enhanced FoxO3a and MT2 expression by promoting histone H3 lysine 9 acetylation. (a) HDAC exerts oxidative stress resistance through the FoxO3a/MT2 pathway. FoxO3a: Forkhead box O3; MT2: Metallothionein 2A. (b and c) qRT-PCR analysis of FoxOa3 (b) and MT2 (c) in H9C2 cells after the indicated treatments (–8 per group). (d and e) Western blotting of the acetylation of H3K9 in purified histones from H9C2 cells after the indicated treatments (d). The quantification of the band intensity (e). Acetylation is normalized to the total histone content H3 and reported to be relative to the MCM-exposed cells. Coomassie blue staining was used as the gel loading control (–6 per group). (f) Chromatin from H9C2 cells after the indicated treatments were immunoprecipitated with anti-histone H3 or anti-AcH3K9, and the purified DNA was analyzed with primer pairs specific for the FoxO3a or MT2 promoters. The results are shown as the ratios of AcH3K9 to total histone H3 (–6 per group). (g–i) Western blotting of FoxO3a and SOD2 in H9C2 cells after the indicated treatments (g). Quantification of the band intensity (h and i). The protein levels of FoxO3a and SOD2 were normalized to those of GAPDH, and the data are expressed as fold changes relative to the control value (–9 per group). (j–l) Western blotting of FoxO3a and SOD2 in the heart tissues from control, LPS, and mice (j). Quantification of the band intensity (k and l). The protein levels of FoxO3a and SOD2 were normalized to those of the GAPDH, and the data are expressed as the fold change relative to the control value ( per group). Data are presented as the . Statistical comparisons were conducted using one-way ANOVA, followed by Tukey’s multiple comparisons test (b, c, d, e, f, h, i, k, and l). The exact values are reported for the indicated comparisons, and indicates statistical significance. , , and for the indicated comparisons.

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