title: Developmental changes in hepatic glucose metabolism in a newborn piglet model: A comparative analysis for suckling period and early weaning period.
abstract: The liver glucose metabolism, supplying sufficient energy for glucose-dependent tissues, is important in suckling or weaned animals, although there are few studies with piglet model. To better understand the development of glucose metabolism in the piglets during suckling period and early weaning period, we determined the hepatic glycogen content, and investigated the relative protein expression of key enzymes of glucogenesis (GNG) and mRNA levels of some glucose metabolism-related genes. During suckling period, the protein level of G6Pase in the liver of suckling piglets progressively declined with day of age compared with that of newborn piglets (at 1 day of age), whereas the PEPCK level stabilized until day 21 of age, indicating that hepatic GNG capacity gradually weakened in suckling piglets. The synthesis of hepatic glycogen, which was consistent with the fluctuation of glycolytic key genes PFKL and PKLR that gradually decreased after birth and was more or less steady during latter suckling period, although both the mRNA levels of GCK and key glucose transporter GLUT2 presented uptrend in suckling piglets. However, early weaning significantly suppressed the hepatic GNG in the weaned piglets, especially at d 3-5 of weaning period, then gradually recovered at d 7 of weaning period. Meanwhile, PFKL, PKLR and GLUT2 showed the similar trend during weaning period. On the contrast, the hepatic glycogen reached the maximum value when the G6Pase and PEPCK protein expression were at the lowest level, although the GCK level maintained increasing through 7 days of weaning period. Altogether, our study provides evidence that hepatic GNG and glycolysis in newborn piglets were more active than other days during suckling period, and early weaning could significantly suppressed glucose metabolism in liver, but this inhibition would progressively recover at day 7 after weaning.
authors.affiliation: Hunan Provincial Engineering Research Center of Healthy Livestock, Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China; University of the Chinese Academy of Sciences, Beijing, 10008, China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Xie
authors.affiliation: Hunan Provincial Engineering Research Center of Healthy Livestock, Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China; Hunan Co-Innovation Center of Animal Production Safety, Hunan Agricultural University, Changsha, 410128, China.
authors.forename: Qinhua
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Hunan Provincial Engineering Research Center of Healthy Livestock, Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China; University of the Chinese Academy of Sciences, Beijing, 10008, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: Hunan Provincial Engineering Research Center of Healthy Livestock, Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China; Hunan Co-Innovation Center of Animal Production Safety, Hunan Agricultural University, Changsha, 410128, China.
authors.forename: Bie
authors.initials: B
authors.lastname: Tan
authors.affiliation: Hunan Provincial Engineering Research Center of Healthy Livestock, Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China; Hunan Co-Innovation Center of Animal Production Safety, Hunan Agricultural University, Changsha, 410128, China.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Food Science and Technology and College of Life Science and Food Engineering, Nanchang University, Nanchang, Jiangxi, 330031, China.
authors.forename: Ze-yuan
authors.initials: ZY
authors.lastname: Deng
authors.affiliation: Hunan Provincial Engineering Research Center of Healthy Livestock, Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China; Hunan Co-Innovation Center of Animal Production Safety, Hunan Agricultural University, Changsha, 410128, China; State Key Laboratory of Food Science and Technology and College of Life Science and Food Engineering, Nanchang University, Nanchang, Jiangxi, 330031, China. Electronic address: wuxin@isa.ac.cn.
authors.forename: Xin
authors.initials: X
authors.lastname: Wu
authors.affiliation: Hunan Provincial Engineering Research Center of Healthy Livestock, Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, Hunan, 410125, China; Hunan Co-Innovation Center of Animal Production Safety, Hunan Agricultural University, Changsha, 410128, China; State Key Laboratory of Food Science and Technology and College of Life Science and Food Engineering, Nanchang University, Nanchang, Jiangxi, 330031, China; School of Life Sciences, Hunan Normal University, Changsha, 41008, China; University of the Chinese Academy of Sciences, Beijing, 10008, China. Electronic address: yinyulong@isa.ac.cn.
authors.forename: Yulong
authors.initials: Y
authors.lastname: Yin
mesh_terms: D000375:Aging / Q000378:metabolism*; D000818:Animals; D000831:Animals, Newborn; D000833:Animals, Suckling / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D007774:Lactation / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D013552:Swine / Q000378:metabolism*; D014886:Weaning
chemical_list: D005947:Glucose
keywords: Early weaning; Glucose metabolism; Liver; Piglets; Suckling period