Fig. 4

Blueberry supplementation preserved islet architecture. a A representative section of pancreas from 14-week-old mice fed with HFD or HFD + B was visualized by immunofluorescence after staining with anti-insulin (green) antibodies. b Changes in β-cell mass in 14-wk-old mice fed with HFD or HFD + B. c β-cell proliferation was evaluated by BrdU staining, the BrdU⁺/insulin⁺ cells to the total insulin⁺ cell ratio was quantified. d Size distribution of islets in HFD and HFD + B groups. Size distribution was categorized by percentage of total islets analyzed. Addition of blueberry to diet significantly increased the number of small islets in aggregates 5000–10,000 μm² when compared to HFD. e Changes in β-cell apoptosis evaluated by TUNEL staining in 20-wk-old mice fed with HFD or HFD + B. The ratio of TUNEL⁺/insulin⁺ cells to the total insulin⁺ cells was quantified. Values are mean ± SD. *P < 0.05; **P < 0.01; n = 3–8 mice per group