GenPhySE, Université de Toulouse, INRAE, ENVT, F-31326, Castanet Tolosan, France.
Present Address: IHAP, Université de Toulouse, INRAE, ENVT, Toulouse, France.
BMC Genomics. 2022 May 30;23(1):407. doi: 10.1186/s12864-022-08634-1.
In mammals, the nutritional status experienced during embryonic development shapes key metabolic pathways and influences the health and phenotype of the future individual, a phenomenon known as nutritional programming. In farmed birds as well, the quantity and quality of feed offered to the dam can impact the phenotype of the offspring. We have previously reported that a 38% reduction in the intake of the methyl donor methionine in the diet of 30 female ducks during the growing and laying periods - from 10 to 51 weeks of age - reduced the body weight of their 180 mule ducklings compared to that of 190 ducklings from 30 control females. The maternal dietary methionine restriction also altered the hepatic energy metabolism studied in 30 of their ducklings. Thus, their plasma glucose and triglyceride concentrations were higher while their plasma free fatty acid level was lower than those measured in the plasma of 30 ducklings from the control group. The objective of this new study was to better understand how maternal dietary methionine restriction affected the livers of their newly hatched male and female ducklings by investigating the hepatic expression levels of 100 genes primarily targeting energy metabolism, amino acid transport, oxidative stress, apoptotic activity and susceptibility to liver injury.
Sixteen of the genes studied were differentially expressed between the ducklings from the two groups. Maternal dietary methionine restriction affected the mRNA levels of genes involved in different pathways related to energy metabolism such as glycolysis, lipogenesis or electron transport. Moreover, the mRNA levels of the nuclear receptors PPARGC1B, PPARG and RXRA were also affected.
Our results show that the 38% reduction in methionine intake in the diet of female ducks during the growing and egg-laying periods impacted the liver transcriptome of their offspring, which may explain the previously observed differences in their liver energy metabolism. These changes in mRNA levels, together with the observed phenotypic data, suggest an early modulation in the establishment of metabolic pathways.
在哺乳动物中，胚胎发育过程中经历的营养状况塑造了关键的代谢途径，并影响未来个体的健康和表型，这种现象被称为营养编程。在养殖鸟类中，母体所摄入的饲料的数量和质量也会影响后代的表型。我们之前曾报道，在生长和产蛋期，30 只母鸭的饮食中减少 38%的甲基供体蛋氨酸（从 10 周到 51 周龄），与 30 只对照母鸭的 190 只骡鸭雏鸭相比，其雏鸭体重降低。母鸭饮食中蛋氨酸限制也改变了我们在 30 只雏鸭中研究的肝能量代谢。因此，与对照组 30 只雏鸭的血浆相比，其血浆葡萄糖和甘油三酯浓度更高，而游离脂肪酸水平更低。本项新研究的目的是通过研究 100 个主要针对能量代谢、氨基酸转运、氧化应激、凋亡活性和肝损伤易感性的基因的肝表达水平，更好地了解母鸭饮食中蛋氨酸限制如何影响其刚孵化的雄性和雌性雏鸭的肝脏。
在所研究的 16 个基因中，两组雏鸭的基因表达存在差异。母鸭饮食中蛋氨酸限制影响了与糖酵解、脂肪生成或电子传递等不同途径相关的基因的 mRNA 水平。此外，核受体 PPARGC1B、PPARG 和 RXRA 的 mRNA 水平也受到影响。
我们的研究结果表明，在生长和产蛋期，母鸭饮食中蛋氨酸摄入减少 38%，影响了其后代的肝脏转录组，这可能解释了之前观察到的其肝脏能量代谢差异。这些 mRNA 水平的变化，以及观察到的表型数据，表明代谢途径的早期调节。
