BAM15 Mediated Mitochondrial Uncoupling Protects Against Obesity and Improves Glycemic Control (2020)
Figure 3

Figure 3. BAM15 stimulates insulin signaling and oxidation of glucose and fatty acids in an AMPK dependent manner.

A-D (A) Representative immunoblots and (B) quantitative analysis of AKT (1 μM insulin: P=0.038), (C) AS160 (- insulin: P=0.036, 1 μM insulin: P=0.0038), and (D) AMPK (- insulin: P=0.018) phosphorylation ± 16 hour BAM15 treatment and 15 minute insulin stimulation (N=3 per condition) in C2C12 myotubes.

E, F (E) Representative immunoblots and quantitative analysis of (F) plasma membrane GLUT4 translocation (P=0.0139) ± 16-hour BAM15 treatment (N=3 per condition) in C2C12 myotubes.

G, H (G) [3-3H]glucose uptake ± 16 hour BAM15 treatment and 30 minute insulin stimulation (N=4 per condition; vehicle vs. vehicle + insulin: P=0.0016, vehicle vs. BAM15: P<0.0001, vehicle vs. BAM15 + insulin: P<0.0001, vehicle + insulin vs. BAM15 + insulin: P=0.0018, BAM15 vs. BAM15 + insulin: P=0.0024) and (H) [1-14C]palmitate oxidation ± 16 hour BAM15 treatment and 5 mM glucose and 1 mM pyruvate (N=6 per condition; no glucose/pyruvate: P<0.0001) in C2C12 myotubes.

(I) Representative immunoblot and quantitative analysis (N=5 per condition; P<0.0001) of AMPK demonstrating loss of function following transfection with an shAMPK construct in C2C12 myotubes.

J, K (J) Representative respirometry plot of intact cells ± shAMPK and 16 hour BAM15 treatment in C2C12 myotubes cells sequentially injected with oligomycin, FCCP, and a cocktail of rotenone and antimycin a (N=5 per condition) and (K) basal and ATP-linked respiration, proton leak, maximal uncoupling, and spare respiratory capacity (N=5 per condition). Basal: shEV vs. shEV + BAM15 (P=0.0317), shEV + BAM15 vs. shAMPK (P<0.0001), shEV + BAM15 vs. shAMPK + BAM15 (P<0.0001). ATP: shEV vs. shAMPK + BAM15 (P=0.0026), shEV + BAM15 vs. shAMPK + BAM15 (P=0.0003), shAMPK vs. shAMPK + BAM15 (P=0.040). Proton leak: shEV vs. shEV + BAM15 (P=0.0052), shAMPK vs. shAMPK + BAM15 (P=0.0394). Maximal: shEV vs. shAMPK + BAM15 (P<0.0001), shEV + BAM15 vs. shAMPK + BAM15 (P<0.0001), shAMPK vs. shAMPK + BAM15 (P<0.0001). Spare Capacity: shEV vs. shAMPK (P=0.0028), shEV vs. shAMPK + BAM15 (P<0.0001), shEV + BAM15 vs. shAMPK (P<0.0001), shEV + BAM15 vs. shAMPK + BAM15 (P<0.0001), shAMPK vs. shAMPK + BAM15 (P<0.0001).

(L) [3-3H]glucose uptake ± shAMPK, 16 hour BAM15 treatment, and 30 minute insulin stimulation in C2C12 myotubes (N=3 per condition). No insulin: shEV vs. shEV + BAM15 (P=0.0001). Insulin: shEV vs. shEV + BAM15 (P=0.0142).

M-O (M) Representative immunoblots and quantitative analysis of (N) AKT (shEV + insulin: P=0.0128, shAMPK - insulin: P=0.0018, shAMPK + insulin, P=0.0124), and (O) AS160 (shEV - insulin: P=0.0283, shEV + insulin: P=0.0137) phosphorylation ± shAMPK, 16 hour BAM15 treatment, and 15 minute insulin stimulation in C2C12 myotubes (N=3 per condition).

Data information: Data are shown as the mean ± SEM. *p<0.05, **p<0.01, ***p<0.01, ****p<0.001. Panels B, C, D, H, K, L, N, and O were assessed by two-way repeated measures ANOVA with Tukey's multiple comparisons. Panel G was assessed by one-way ANOVA with Tukey's multiple comparisons. Panels F and I were assessed by unpaired Student's t-test.