Figure 1.

Endothelial insulin resistance in type 2 diabetes (T2D) mice and humans is not associated with reduced heat shock protein 72 (HSP72) in aortas and endothelial cells, respectively. A: insulin-induced relaxation, via wire-myography, in aortic rings collected from male db+ and db/db mice (db+ n = 11; db/db n = 7). Two-way ANOVA with repeated-measures and Bonferroni post hoc test. HSP72 (B) and phospho-c-Jun amino-terminal kinase (JNK)/JNK protein content (C) in aortas from male db+ and db/db mice, measured by Western blotting (db+ n = 11; db/db n = 9). Unpaired two-tailed Student’s t test, respectively. D: representative Western blot bands for proteins of interest in mouse aortas. E: plasma insulin concentration (top; healthy n = 20; T2D n = 18), relative leg blood flow (percent change from baseline) (middle; healthy n = 20; T2D n = 20), and relative leg vascular conductance (percent change from baseline) (bottom; healthy n = 20; T2D n = 20) in response to an oral glucose load (75 g) in healthy and T2D subjects. Two-way ANOVA with repeated-measures and Bonferroni post hoc test. HSP72 (F) and phospho-JNK/JNK protein content (G) in venous endothelial cells collected from healthy and T2D subjects, measured by quantitative immunofluorescence intensity (healthy n = 20; T2D n = 19). Unpaired two-tailed Student’s t test, respectively. H and I: representative images of quantitative immunofluorescence intensities of HSP72 and phospho-JNK/JNK, respectively. Means ± SE and individual data, when appropriate, are reported. In A and E (middle and bottom), *significance using Bonferroni-adjusted pairwise comparisons (P < 0.05). In E (top), #significant main effect of time (P < 0.05). vWF, von Willebrand factor.