Fig. 2

Hyperglycemic condition induces astrogliosis and the proliferation of astrocytes

(A) Representative immunohistochemical images of hippocampal regions of vehicle- or STZ- injected mice. The coronal sections of brain were stained with anti-GFAP (green) and anti-Iba1 (red). DAPI represents nuclear signal (blue). Scale bars = 50 μm. (B-E) Quantification of the mean fluorescence intensity (MFI) of GFAP and Iba1 normalized with DAPI (B and D), and the number of astrocytes (GFAP⁺ cells, C) and microglia (Iba1⁺ cells, E) normalized with DAPI⁺ cells. (6 mice, vehicle; 7 mice, STZ group). (F) Experimental scheme for BrdU-based cell proliferation assay. TdTomato^fl/fl;Aldh1l1^CreERT2 mice were subjected to tamoxifen administration for five days and injected with STZ (d10) to induce hyperglycemia. After another five days, mice were injected with BrdU (d15, 50 mg/kg) for five consecutive days. (G) Immunohistochemical analysis of BrdU cell proliferation assay in the hippocampal region of vehicle- and STZ-injected mice. (6 mice, vehicle; 7 mice, STZ group) Cells were stained with anti-BrdU (green) and astrocytes were labeled by tdTomato (red). DAPI represents nuclear signal (blue). The boxed areas indicate the colocalization of BrdU and astrocytes. (H-I) Quantification of astrocytes (tdTomato⁺ cells, H) and proliferating astrocytes (BrdU⁺ tdTomato⁺ cells, I) normalized by DAPI count. (J) Quantification of relative BrdU-expressing astrocytes per total BrdU⁺ cells. Scale bars = 50 μm (20X) and 20 μm (enlarged, 40X). Asterisks indicate significant differences in Student’s two-tailed, unpaired t test. *P < 0.05, **P < 0.01, n.s. not significant