Figure 5

Impact of adiponectin deficiency on retinal vascular damage in streptozotocin-induced diabetes. (A) Streptozotocin (STZ) was intraperitoneally administered to 8-week-old male wild-type (WT) and adiponectin knockout (APN-KO) mice for 5 consecutive days. Mice were analyzed at 4 weeks after the onset of diabetes (Day 1). To evaluate retinal vascular permeability, a mixed solution of Hoechst and fluorescein isothiocyanate (FITC)-dextran was transcardially injected into each mouse, and retinas were removed at 5 min after injection. WT mice without STZ injection were also analyzed as control (Cont). (B and C) Changes in body weights (B) and plasma glucose concentrations under 4-h fasting conditions at Day 27 (the day before analysis). n = 6 for Cont, n = 9 for STZ-WT, and n = 8 for STZ-APN-KO. Data are the mean ± SEM; ***P < 0.001 vs Cont. N.S., not significant (one-way ANOVA with Tukey’s post hoc test). (D) Representative immunofluorescence images for Hoechst (red) and FITC-dextran (green). Scale bar = 100 μm. (E) Extravascular Hoechst-positive cell numbers (left) and % area (right) were calculated using two randomly obtained sections for each mouse. n = 6 for Cont, n = 9 for STZ-WT, and n = 8 for STZ-APN-KO. Data are the mean ± SEM; *P < 0.05 and **P < 0.01. N.S., not significant (one-way ANOVA with Tukey’s post hoc test). (F) Representative immunofluorescence images for vascular cellular adhesion molecule-1 (VCAM-1) (red) and isolectin B4 (IB4) (gray). Scale bar = 100 μm. (G) The % area of the VCAM-1-positive region in IB4-positive endothelium. Quantification was performed using two randomly obtained sections for each mouse. n = 4 for STZ-WT and n = 3 for STZ-APN-KO. Data are the mean ± SEM; *P < 0.05 (two-tailed Student’s t-test). (H). Representative immunofluorescence images for claudin-5 (green) and CD31 (gray). Scale bar = 25 μm (left panels) and 100 μm (middle and right panels).