Fig. 1: Less collagen and vascular smooth muscle cells are associated with future cardiovascular events in type 2 diabetes .
a Atherosclerotic plaques from patients with type 2 diabetes (T2D; n = 12 patient samples) have smaller fibrous caps (cap area and % of plaque area) compared to plaques from patients without diabetes (n = 18 patient samples). MOVAT pentachrome staining was used to assess collagen. Dark dotted line marks the fibrous cap. Red line marks lumen. Scale bars 1 mm. T2D plaques (n = 72 patient samples) have significantly lower levels of collagen compared to plaques from patients without diabetes (n = 147 patient samples) measured in b whole plaque tissue homogenates and c histologically in the most stenotic region of the plaque (T2D, n = 68; no diabetes, n = 135 patient samples). Data is presented as violin plots (lines indicating median and interquartile range). Two-tailed Mann–Whitney U-test was used to determine the level of significance. d Kaplan–Meier curve showing an increased risk for cardiovascular events among T2D patients with a calculated plaque vulnerability index (VI) in the 3rd tertile (red line) compared to patients with a plaque VI in the 1st and 2nd tertiles (blue line; p = 0.03). Numbers of events are shown in brackets. Two-sided log rank test was used (n = 61 patient samples). e A multiple linear regression analysis identified (ordered by absolute value of beta) smaller plaque areas (% plaque area) of collagen (MOVAT) and vascular smooth muscle cells (alpha-actin) as the histological components with the strongest influence on the calculated VI in plaques from T2D patients (n = 61). Beta coefficients and their 95% confidence interval are shown. p = 0.001 (alpha-actin), p = 0.04 (Movat), p = 0.10 (Glycophorin A), p = 0.48 (CD68) and p = 0.07 (ORO), according to the two-sided Student’s t-tests. Solid points depict significant associations (p < 0.05). T2D type 2 diabetes, ORO Oil Red O, VI vulnerability index. Source data are provided in a source data file.
