Midlife intervention of Dendrobium officinale extract modulates gut microbiota to activate InR-Nrf2 axis, promoting intestinal health and longevity

Figure 4 Inhibition of intestinal stem cells proliferation and maintenance of intestinal microbiota homeostasis by Dendrobium officinale extract. A: Representative images obtained at 7 days, 22 days, and 42 days from Dendrobium officinale extract (DOE)-intervened esg-gal4 > UAS-GFP/cyo flies showing midgut enterocytes [4’,6-diamidino-2-phenylindole (DAPI)], intestinal stem cells (ISCs)/entero-blasts [green fluorescent protein (GFP)], and ISCs [Delta (DI)]. Scale bar = 10 μm; B: Quantification of esg-GFP⁺ or DI⁺ cells as percentages of total DAPI-stained cells in female flies (n = 3); C: Quantification of the mitotic index (phospho-histone H3; phospho-histone H3-positive cells per midgut) in female flies (n = 3); D: Bacterial abundance at the phylum level in female flies; E: Relative abundance of the dominant strain in female flies (phylum level); F: Bacterial abundance at the phylum level in male flies; G: Relative abundance of the dominant strain in male flies (phylum level); H: Bacterial abundance at the genus level in female flies; I: Relative abundance of the dominant strain in female flies (genus level); J: Bacterial abundance at the genus level in male flies; K: Relative abundance of the dominant strain in male flies (genus level); L: Growth status of Acetobacter sp. in the gut of flies at 10-day, 20-day, 30-day, 40-day, and 40-day + DOE; M: Quantification of Acetobacter sp. in female flies (n = 3); N: Growth status of Lactobacillus sp. in the gut of flies at 10-day, 20-day, 30-day, 40-day, and 40-day + DOE; O: Quantification of Lactobacillus sp. in male flies (n = 3). The data are expressed as the mean ± SD. Data were analyzed by Student’s t-test (two groups) or one-way analysis of variance with post-hoc test (multiple comparisons). ^aP < 0.05 vs 7-day group. ^bP < 0.01 vs 7-day group. ^cP < 0.0001 vs 7-day group. ^dP < 0.0001 vs 42-day group. ^eP < 0.05 vs control group. ^fP < 0.0001 vs 10-day group. ^gP < 0.01 vs 20-day group. ^hP < 0.05 vs 40-day group. ⁱP < 0.001 vs 40-day group. DOE: Dendrobium officinale extract; DI: Delta; GFP: Green fluorescent protein; DAPI: 4’,6-diamidino-2-phenylindole; PH3: Phospho-histone H3; F: Female; M: Male.