Capillary morphology, CBM thickness and correlation analysis in human VAT. Representative transmission electron micrographs of transverse sections of VAT capillaries in the lean control subjects and in the normoglycemic (ob N), prediabetic (ob preDM) and diabetic (ob T2DM) obese patients (A). Regions in the white boxes in (A) are shown at higher magnification in (B). White arrowheads indicate the CBM thickness, which was measured at multiple points in each micrograph. CBM thickness (nm) in the VAT was analyzed in 6 lean, 5 ob N, 5 ob preDM and 5 ob T2DM subjects (C). Data are reported as box plot graph with the lowest and highest values (whiskers), the medians (lines) and the 5th and 95th percentiles (black circles outside the whiskers). Correlation analysis was performed between CBM thickness, FPG of all patients with the exclusion of one outlier indicated by a triangle, and HOMAIR of 14 obese patients (D,E). Data was analyzed using the Kruskal-Wallis test (Dunn’s method) in (C), ***P ≤ 0.001, and Pearson’s correlation coefficient in (D,E).