Use of short-term high energy dietary for estimating transcriptional profiling of liver tissues in sheep

Abstract

28This study aimed to evaluate if short-term high energy dietary has any 29 stimulatory effects on liver function and metabolic status in sheep. The experiment 30 was carried out using 30 Dorset×Han crossbred ewes (age, 9 ± 0.6 months; weight, 31 36.58 ± 2.56kg) allocated into two treatments, the control group (DE 11.72 MJ/d; DP 32 79.71 g/d) and the high energy group (DE18.75 MJ/d; DP 108.44 g/d), respectively. 33 Experiment lasted 20 days, including 10 d for adaption. Blood samples of these ewes 34 were collected to detect the concentrations of glucose, insulin, leptin, and cholesterol, 35 respectively. Then, animals were sacrificed and optimal liver samples subjected to 36 explore the genome-wide transcriptome analysis. Results showed that the weight gain 37 was significantly increased in the high energy group, compared with those in the 38 control group (p< 0.01). The concentrations of glucose, insulin, leptin, and cholesterol 39 were also influenced by short-term nutritional supplementation at different levels. 40 Subsequently, 622 differentially expressed genes were identified by pairwise 41 comparison. Of these, 271 genes were down regulated while 351 genes were up 42 regulated. qRT-PCR analysis of 10 randomly selected genes were consistent with the 43 sequencing results. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and 44 Genomes (KEGG) pathways revealed 12 DEGs (including PDK4, ABCA9, 45 ALDH6A1, SLC45A3, G0S2, PPARGC1, GHRHR, GHR, DGKI, SOCS2, LPIN1 and 46 CSKMT) were significantly enriched in cellular carbohydrate catabolic and metabolic 47 process, phosphorelay sensor and phosphotransferase kinase activity, generation of 48 precursor metabolites and energy, lipid metabolic and transport process, positive 3 49 regulation of cellular metabolic process, acyl-CoA desaturase activity and 50 monosaccharide metabolic process. Additionally, we concluded an interaction 51 network related to energy metabolism, which might be contributed to elucidate the 52 precise molecular mechanisms of related genes associated with energy metabolism in 53 the liver tissues of sheep. 54 INTRODUCTION 56Nutrition plays a crucial role in regulating the growth and reproductive 57 performance of farm animals. Energy homeostasis exerts a significant influence on 58 animal health and body condition [1]. Positive energy balance results in increased 59 leptin and insulin concentrations in the blood, which subsequently increased glucose 60 uptake. Previous studies have shown that short-term nutritional supplementation for 4 61 to 11 days exerts significant influences on the blood metabolites and the reproductive 62 performance of ewes [2][3]. Additionally, it is suggested that nutritional 63 supplementation can directly increase the concentrations of several metabolic 64 hormones in ewes, including glucose, insulin, IGF-1, and leptin [4]. However, to our 65 knowledge, there are few studies on the effect of nutritional supplementation on the 66 liver growth, especially its specific regulatory mechanism...