This study aimed to evaluate if a short-term nutritional supplementation has any stimulatory effects on liver function and metabolic status in sheep. The experiment was carried out using 30 Dorset×Han crossbred ewes (age, 9 ± 0.6 months; weight, 36.58 ± 2.56 kg) allocated into two treatments, the control group (AD group: DE 11.72 MJ/d; DP 79.71 g/d) and the nutritional supplementation group (HE group: DE18.75 MJ/d; DP 108.44 g/d), respectively. Experiment lasted 20 days, including 10 d for adaption. Blood samples of these ewes were collected to detect the concentrations of glucose, insulin, leptin, and cholesterol. Then, liver samples of these animals were collected to explore the genome-wide transcriptome analysis. Results showed that the weight gain was significantly increased in the nutritional supplementation group, compared with those in the control group (p = 1.27e-03). The concentrations of glucose, insulin, leptin, and cholesterol were also influenced, compared with the AD groups, higher glucose concentrations ranging from 0.10 to 1.11 mmol/L were observed in the HE groups. The concentrations of insulin and leptin varied over time and they were higher in HE groups. The cholesterol concentration was lower in the HE groups. Furthermore, 622 differentially expressed genes (DEGs) were identified between different treatments. Of these, 271 genes were down regulated while 351 genes were up regulated. qRT-PCR analysis of 10 randomly selected genes were consistent with the sequencing results. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways revealed these DEGs in HE group were significantly enriched in energy and lipid metabolism, such as cellular carbohydrate catabolic and metabolic process (DGKI, SOCS2, GHR, GHRHR, CSKMT), lipid metabolic and transport process (ALDH6A1, ABCA9, G0S2, PPARGC1) and monosaccharide metabolic process (PDK4, LPIN1, ABCA9, SLC45A3), etc. Additionally, we concluded an interaction network related to energy metabolism, which showed that a short-term nutritional supplementation in sheep may be associated with liver metabolism by PPAR signaling pathway, AMPK signaling and Insulin signaling pathway. Importantly, PDK4 and G0S2 may be core essential genes and play an important role in these pathways. All these results might be contributed to detect related genes associated with energy metabolism in the liver tissues of sheep. Overall, the findings presented here provide the first evidence for key candidate genes affecting liver function.

本研究旨在评估短期营养补充剂是否对绵羊的肝功能和代谢状态有任何刺激作用。实验使用 30 头 Dorset × Han 杂交母羊（年龄，9 ± 0.6 个月；体重，36.58 ± 2.56 kg）进行，分为两个处理组，对照组（AD 组：DE 11.72 MJ/d；DP 79.71 g/d ）和营养补充组（HE组：DE18.75 MJ/d；DP 108.44 g/d）。实验历时20天，其中适应10天。收集这些母羊的血液样本以检测葡萄糖、胰岛素、瘦素和胆固醇的浓度。然后，收集这些动物的肝脏样本以探索全基因组转录组分析。结果显示，营养补充组体重增加显着增加，与对照组相比（p = 1.27e-03）。葡萄糖、胰岛素、瘦素和胆固醇的浓度也受到影响，与 AD 组相比，HE 组观察到更高的葡萄糖浓度，范围为 0.10 至 1.11 mmol/L。胰岛素和瘦素的浓度随时间而变化，并且在 HE 组中更高。HE组的胆固醇浓度较低。此外，在不同处理之间鉴定了 622 个差异表达基因 (DEG)。其中，271个基因下调，351个基因上调。10个随机选择的基因的qRT-PCR分析与测序结果一致。基因本体论（GO）和京都基因与基因组百科全书（KEGG）途径显示HE组中的这些DEGs在能量和脂质代谢中显着富集，DGKI、SOCS2、GHR、GHRHR、CSKMT）、脂质代谢和转运过程（ALDH6A1、ABCA9、G0S2、PPARGC1）和单糖代谢过程（PDK4、LPIN1、ABCA9、SLC45A3）等。此外，我们得出了一个相关的相互作用网络能量代谢，表明羊的短期营养补充可能通过 PPAR 信号通路、AMPK 信号通路和胰岛素信号通路与肝脏代谢有关。重要的是，PDK4和G0S2可能是核心必需基因并在这些途径中发挥重要作用。所有这些结果都可能有助于检测绵羊肝组织中与能量代谢相关的相关基因。总的来说，这里提出的发现为影响肝功能的关键候选基因提供了第一个证据。