Figure 2

(A) Zebrafish were treated with 40 µM SFN or 1 µM tBHQ during the pharyngula, hatching, or protruding-mouth stage for 6 h and then fixed, and Nrf2a protein was labeled using immunohistochemistry (IHC). Z-stacks of the islet were acquired via confocal microscopy. (A) Islet volume and (B) islet mean fluorescence intensity (FI) of Nrf2a protein were measured with Nikon NIS elements software (available at Light Microscopy Core analysis workstations at the UMass Amherst Institute for Applied Life Sciences; https://www.microscope.healthcare.nikon.com/bioimaging-centers/nic-and-cofe/university-of-massachusetts-amherst). Representative images of each group at the (C) pharyngula, (D) hatching, and (E) protruding-mouth stage are shown. Images show max intensity projections of the islet Z-stack (circled in yellow) where FITC (green) represents β-cells, TRITC (red) represents Nrf2a protein, and DAPI (blue) represents nuclei. Statistics were performed with a two-way ANOVA and Fisher’s LSD post hoc test. n = 5–12 fish. Letters indicate significant differences (p ≤ 0.05) among groups. Scale bar = 25 µm.