FIG. 2.

Cardiac loss of IRS1 and IRS2 proteins in HFD, db/db, and L-DKO mice and cardiac dysfunction in L-DKO hearts compared with control (CNTR). Immunoblot analysis of insulin-signaling molecules in hearts and cardiac function of 5-month-old HFD, db/db mice, and control (A) and 6-month-old L-DKO mice (B and C) (n = 6–10). *P < 0.05 vs. control. All mice were in a random-fed state. Representative images of immunoblotting from two to three mice are shown. GAPDH, glyceraldehyde-3-phosphate dehydrogenase. D: Relative cardiac ATP content in the L-DKO and control mice (n = 6). *P < 0.05. Cardiac histology is shown by representative transverse section of left ventricle stained with hematoxylin and eosin (original magnification ×200) (E) and Masson Trichrome (original magnification ×200) (F), in which the percentage of the fibrotic area under 500 µm² of sections was presented. *P < 0.05 vs. control. G: Relative mRNA levels in the random-fed hearts of L-DKO and control mice. Data are expressed as the mean ± SEM (n = 4). *P < 0.05 vs. control. H: Oil red O staining of hearts from 6-month-old L-DKO, db/db, and control mice. I: Cardiac function of 6-month-old H-DKO-het mice (n = 6 per group). *P < 0.05 vs. control. J: Immunoblot analysis of insulin-signaling molecules in the random-fed hearts of H-DKO-het and control mice at random-fed state (n = 2–4 mice per group). *P < 0.05 vs. control.