DNA methylation inhibits DNA transcription by the addition of methyl residues to cysteine within the CpG islands of gene promoters. The process of DNA methylation can be modulated by environmental factors such as intestinal microbiota. In poultry, the composition of the intestinal microbiota can be stimulated by in ovo delivery of synbiotics. The present study aims to determine the effect of Lactobacillus synbiotics delivered in ovo on the level of hepatic DNA methylation in broiler chickens. In ovo stimulation was performed on day 12 of egg incubation. Bioactive compounds delivered in ovo included (S1)—Lactobacillus salivarius with GOS and (S2)—Lactobacillus plantarum with RFO. Samples were collected from six individuals from each group on day 42 post-hatching. DNA methylation of five genes selected on the basis of the transcriptome data were analyzed using the qMSP method. Significant changes were observed in DNA methylation of genes in liver including ANGPTL4 and NR4A3, after S2 delivery. The obtained results confirm that the downregulation of metabolic gene expression in the liver mediated by in ovo stimulation had epigenetic characteristics.

中文翻译：

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肉鸡中乳酸菌合生素对微生物群早期刺激的响应的肝脏 DNA 甲基化

DNA 甲基化通过向基因启动子 CpG 岛内的半胱氨酸添加甲基残基来抑制 DNA 转录。DNA甲基化过程可以通过肠道微生物群等环境因素进行调节。在家禽中，肠道微生物群的组成可以通过合生元的卵内递送来刺激。本研究旨在确定卵内递送的乳杆菌合生元对肉鸡肝脏 DNA 甲基化水平的影响。在卵孵化的第 12 天进行卵内刺激。卵内递送的生物活性化合物包括 (S1)-具有 GOS 的唾液乳杆菌和 (S2)-具有 RFO 的植物乳杆菌。在孵化后第 42 天从每组的 6 个个体中收集样品。使用 qMSP 方法分析基于转录组数据选择的五个基因的 DNA 甲基化。在 S2 分娩后，肝脏中基因（包括 ANGPTL4 和 NR4A3）的 DNA 甲基化发生了显着变化。所得结果证实，卵内刺激介导的肝脏代谢基因表达下调具有表观遗传特征。