Fig. 3

Influence of FPI and IGF-1 on goblet cells and intestinal epithelial stem cells (IESC). PAS staining was used to assess the number of goblet cells per crypt in the ileum at 3 (a–c) and 35 DPI. Quantitative analysis revealed that FPI significantly reduced the number of goblet cells per crypt at 3 DPI (d) and 35 DPI (e) and this was increased by IGF-1 treatment. Proliferating IESCs in the crypts were determined by quantifying Ki67 + labeled cells at 3 (i) and 35 (j) DPI. In f–h, representative micrographs of Ki67 + staining in the crypts of the ileum at 35 DPI, with areas designated by the white arrow enlarged in the corresponding inset. At 3 DPI (i), the FPI + Veh showed a non-significant reduction (p = 0.2152, NS) in the number of Ki67 + cells in the crypts. The FPI + IGF-1 group exhibited a significant reduction (p < 0.01 vs. to Sham + Veh) in the Ki67 + cells in the crypts. Conversely at 35 DPI (j), FPI significantly increased the number of Ki67 + cells, and this was significantly reduced by IGF-1 treatment. This suggests that FPI resulted in a delayed increase in IESC proliferation, whereas IGF-1 reduced the number of Ki67 + cells at both timepoints examined. For all rats, 3 slides were assessed, with 3 sections per slide measured. Data are represented as Mean ± SEM; N for 3 DPI: 4 Sham + Veh, 5 FPI + Veh, 5 FPI + IGF1. N for 35 DPI: 3 Sham + Veh, 3 FPI + Veh, 4 FPI + IGF1. *p < 0.05; **p < 0.01. Scale bar in a = 5 µm; scale bar in b,c = 10 µm; scale bar in h = 10 µm for f–h