摘要
Nutritional stimulation of the developing small intestine of chick embryos can be conducted by in-ovo feeding(IOF).We hypothesized that IOF of glutamine and leucine can enhance small intestinal development by promoting proliferation and differentiation of multipotent small intestinal epithelial cells.Broiler embryos(n=128)were subject to IOF of glutamine(IOF-Gln),leucine(IOF-Leu),NaCl(IOF-NaCl)or no injection(control)at embryonic d 17(E 17).Multipotent,progenitor and differentiated cells were located and quantified in the small intestinal epithelium between E 17 and d 7 after hatch(D 7)in all treatment groups by immunofluorescence of SRY-box transcription factor 9(Sox9)and proliferating cell nuclear antigen(PCNA),in-situ hybridization of leucine-rich repeat containing G-protein coupled receptor 5(Lgr5)and peptide transporter 1(PepT1)and histochemical goblet cell staining.The effects of IOF treatments at E 19(48 h post-IOF),in comparison to control embryos,were as follows:total cell counts increased by 40%,33%and 19%,and multipotent cell counts increased by 52%,50%and 38%,in IOF-Gln,IOF-Leu and IOF-NaCl embryos,respectively.Only IOF-Gln embryos exhibited a significance,36%increase in progenitor cell counts.All IOF treatments shifted Lgr5+ stem cell localizations to villus bottoms.The differentiated,PepT1+region of the villi was 1.9 and 1.3-fold longer in IOF-Gln and IOF-Leu embryos,respectively,while goblet cell densities decreased by 20%in IOF-Gln embryos.Postehatch,crypt and villi epithelial cell counts were significantly higher IOF-Gln chicks,compared to control chicks(P<0.05).We conclude IOF of glutamine stimulates small intestinal maturation and functionality during the peri-hatch period by promoting multipotent cell proliferation and differentiation,resulting in enhanced compartmentalization of multipotent and differentiated cell niches and expansions of the absorptive surface area.
基金
This research was supported by Research Grant No.US-5074-18CR from the United States-Israel Binational Agricultural Research and Development(BARD)Fund.
