GABI, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France.
Dev Dyn. 2019 Oct;248(10):948-960. doi: 10.1002/dvdy.91. Epub 2019 Aug 2.
Nutritional changes can affect future lactation efficiency. In a rabbit model, an obesogenic diet initiated before puberty and pursued throughout pregnancy enhances mammary differentiation, but when started during the neonatal period can cause abnormal mammary development in early pregnancy. The aim of this study was to investigate the impact of an unbalanced diet administered during the pubertal period only.
Consuming an obesogenic diet at puberty did not affect either metabolic parameters or certain maternal reproductive parameters at the onset of adulthood. In contrast, at Day 8 of pregnancy, epithelial tissue showed a lower proliferation rate in obesogenic-diet fed rabbits than in control-diet fed rabbits. Wap and Cx26 genes, mammary epithelial cell differentiation markers, were upregulated although Wap protein level remained unchanged. However, the expression of genes involved in lipid metabolism and in alveolar formation was not modified.
Taken together, our results demonstrate that the consumption for 5 weeks of an obesogenic diet during the pubertal period initiates mammary structure modifications and affects mammary epithelial cell proliferation and differentiation. Our findings highlight the potentially important role played by unbalanced nutrition during critical early-life windows in terms of regulating mammary epithelial cell differentiation and subsequent function in adulthood.
营养变化会影响未来的泌乳效率。在兔模型中，青春期前开始并贯穿整个孕期的致肥胖饮食会增强乳腺分化，但如果在新生儿期开始，则会导致早孕时乳腺发育异常。本研究旨在探讨仅在青春期给予不均衡饮食的影响。
青春期摄入致肥胖饮食不会影响成年期开始时的代谢参数或某些母体生殖参数。相比之下，在妊娠第 8 天，与对照组相比，致肥胖饮食组的上皮组织增殖率较低。Wap 和 Cx26 基因，乳腺上皮细胞分化标志物，上调，尽管 Wap 蛋白水平保持不变。然而，参与脂质代谢和肺泡形成的基因表达没有改变。
总之，我们的研究结果表明，青春期 5 周摄入致肥胖饮食会引发乳腺结构改变，并影响乳腺上皮细胞增殖和分化。我们的研究结果强调了在关键的早期生命窗口期间不平衡营养可能发挥的重要作用，以调节乳腺上皮细胞分化和随后的成年期功能。
