Effect of selected extracts on expression of GLUT4, Insulin and AMPK pathway in C2C12 cells.

<p>Cells were differentiated and treated for 18 hours with vehicle or with EE and HWE of the 5 selected plants. Metformin (400 μM, 18 hours), AICAR (2 mM, 2 hours) or insulin (100 nM, 30 min) was applied as positive controls for the AMPK or insulin pathways, respectively. GLUT4 (3A), phosphorylation of AMPK (3D), phosphorylation of Akt (3G) were measured by western blot and results (3B, 3E, 3H) were expressed as means ± SE for 3 separate experiments, normalized to the vehicle-treated condition. # Denotes EE samples significantly different from vehicle control (p < 0.05), one-way ANOVA and post hoc Dunnett's test. $ Denotes HWE samples significantly different from vehicle control (<i>p</i> < 0.05), one-way ANOVA and post hoc Dunnett's test. * (<i>p</i> < 0.05), **(<i>p</i> < 0.01) and *** (<i>p</i> < 0.001) denote significant differences between EE and HWE counterpart, two-way ANOVA. Correlation results (3C, 3F) were analyzed by linear regression and the equations were y = 32.06x + 52.95 (R = 0.80, <i>p</i> < 0.05), y = 11.602x + 84.825 (R = 0.46, <i>p</i> < 0.05), respectively.</p

Metabolites analysis of selected hot water extracts based on stimulating glucose uptake activity.

<p>PCA scores (5A), OPLS-DA scores (5B) S-plot (5C) of UPLC-QTOF metabolome of HWE of Cree plants. Those stimulating glucose transport (<i>R</i>. <i>gromenlandicum</i>, <i>R</i>. <i>tomentosum</i>, and <i>S</i>. <i>purpurea</i>) grouped seperately from inactive ones (<i>K</i>. <i>angusfolia</i> was found to be an outlier and was excluded from the process). The 95% confidence interval for each group is given. In the S-plot, the metabolome of the active plants was compared with the inactive plants to identify discriminant biomarkers with <i>K</i>. <i>angustifolia</i> excluded. In Fig 5D, quercetin 3-O-α-L-arabinopyranoside (Q3A, 50 μM) stimulated GU in C2C12 cells, 140% compared with vehicle control.</p

Effect of selected extracts on the modulation of insulin and AMPK pathway in H4IIE cells.

<p>The cells were treated for 18h with vehicle control, insulin (100 nM), EE or HWE plants extracts. Metformin (400 μM, 18 hours), AICAR (2 mM, 2 hours) or insulin (100 nM, 18 hours) was used as positive controls for AMPK or insulin pathways, respectively. Phosphorylation of AMPK (4A) and of Akt (4D) was measured by western blot and results (4B, 4E) expressed as means ± SE for 3 separate experiments, normalized to the vehicle-treated condition. # Denotes EE samples significantly different from vehicle control (p < 0.05), one-way ANOVA and post hoc Dunnett's test. $ Denotes HWE samples significantly different from vehicle control (p < 0.05), one-way ANOVA and post hoc Dunnett's test. Correlation results (4C) were analyzed by linear regression and the equation was y = -45.418x + 285.3 (R = 0.48, <i>p</i> < 0.05).</p

Effects of extracts on muscle glucose transport.

<p>C2C12 skeletal muscle cells were treated with either 0.1% DMSO (vehicle), Metformin (400 μM), EE and HWE (at concentrations described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135721#pone.0135721.t001" target="_blank">Table 1</a>) for 18 hours, or with insulin (100 nM) for 30 min. Results represent means ± SE for 3 separate experiments, normalized to the vehicle-treated condition. # Denotes EE samples significantly different from vehicle control (<i>p</i> < 0.05), one-way ANOVA and post hoc Dunnett's test. $ Denotes HWE samples significantly different from vehicle control (p < 0.05), one-way ANOVA and post hoc Dunnett's test. * (<i>p</i> < 0.05), **(<i>p</i> < 0.01) and *** (<i>p</i> < 0.001) denote significant differences between respective EE and HWE counterparts, two-way ANOVA.</p

List of investigated plant species and the concentrations of the extracts tested in cells.

<p>List of investigated plant species and the concentrations of the extracts tested in cells.</p