RNA-seq of liver samples after tryptophan supplementation in low birthweight piglet model

Low birthweight (LBW) has been associated with higher rate of mortality and morbidity and the development of metabolic complications, leaving burdens on livestock production and human health care. The feasibility of LBW metabolic restoration via postnatal nutrition compensation has been verified and the role of one of essential amino acids, L-tryptophan (Trp), on rescuing lipid metabolism in LBW was determined, while the underlying molecular mechanism and key gene regulation is little known. Our study was conducted to identify the unique molecular mechanisms between LBW and normal birthweight (NBW), and to identify the metabolic restoration related genes and biological processes (BP) after dietary Trp supplementation in LBW piglet model. We found that differentially expressed genes (DEG) between LBW and NBW were related to fatty acid response based on gene ontology (GO) enrichment analysis, and LBW piglets supplemented with Trp showed lower postprandial plasma triglycerides (TG) level as NBW, with similar expression feature of lipid metabolism related genes.

低出生体重（Low birthweight, LBW）与更高的死亡率、发病率及代谢并发症的发生风险显著相关，给畜禽生产与人类医疗保健带来了沉重负担。目前，通过产后营养补偿实现低出生体重代谢修复的可行性已得到验证，且必需氨基酸之一的L-色氨酸（L-tryptophan, Trp）在改善低出生体重个体脂质代谢中的作用已被明确，但相关潜在分子机制与关键基因调控过程仍鲜有研究。本研究旨在阐明低出生体重与正常出生体重（Normal birthweight, NBW）之间的独特分子机制，并筛选低出生体重仔猪模型经日粮添加色氨酸后，与代谢修复相关的基因及生物学过程（Biological Processes, BP）。通过基因本体（Gene Ontology, GO）富集分析发现，低出生体重与正常出生体重个体间的差异表达基因（Differentially Expressed Genes, DEG）与脂肪酸应答通路密切相关；日粮添加色氨酸的低出生体重仔猪，其餐后血浆甘油三酯（Triglycerides, TG）水平降至与正常出生体重仔猪相当的水平，且脂质代谢相关基因的表达特征也与之相似。