title: Effects of Alpha-Ketoglutarate on Glutamine Metabolism in Piglet Enterocytes in Vivo and in Vitro.
abstract: Alpha-ketoglutarate (AKG) plays a vital part in the tricarboxylic acid cycle and is a key intermediate in the oxidation of L-glutamine (Gln). The study was to evaluate effects of AKG on Gln metabolism in vivo and in vitro. A total of twenty-one piglets were weaned at 28 days with a mean body weight (BW) of 6.0 ± 0.2 kg, and randomly divided into 3 groups: corn soybean meal based diet (CON group); the basal diet with 1% alpha-ketoglutarate (AKG treatment group); and the basal diet with 1% L-glutamine (GLN treatment group). Intestinal porcine epithelial cells-1 (IPEC-1) were incubated to investigate effects of 0.5, 2, and 3 mM AKG addition on Gln metabolism. Our results showed that there were no differences (P > 0.05) among the 3 treatments in initial BW, final BW, and average daily feed intake. However, average daily gain (P = 0.013) and gain:feed (P = 0.041) of the AKG group were greater than those of the other two groups. In comparison with the CON group, the AKG and GLN groups exhibited an improvement in villus length, mucosal thickness, and crypt depth in the jejunum of piglets. Serum concentrations of Asp, Glu, Val, Ile, Tyr, Phe, Lys, and Arg in the piglets fed the 1% AKG or Gln diet were lower than those in the CON group. Compared with the CON group, the mRNA expression of jejunal and ileal amino acid (AA) transporters in the AKG and GLN groups were significantly increased (P < 0.05). Additionally, the in vitro study showed that the addition of 0.5, 2, and 3 mM AKG dose-dependently decreased (P < 0.05) the net utilization of Gln and formulation of ammonia, Glu, Ala, and Asp by IPEC-1. In conclusion, dietary AKG supplementation, as a replacement for Gln, could improve Gln metabolism in piglet enterocytes and enhance the utilization of AA.
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, Hunan Provincial Engineering Research Center of Healthy Livestock, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Institute of Subtropical Agriculture, Chinese Academy of Sciences , Changsha, Hunan 410125, China.|University of the Chinese Academy of Sciences , Beijing 10008, China.
authors.forename: Liuqin
authors.initials: L
authors.lastname: He
authors.affiliation: College of Animal Science and Technology, Hunan Agricultural University , Changsha, Hunan 410128, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Li
authors.affiliation: College of Animal Science and Technology, Hunan Agricultural University , Changsha, Hunan 410128, China.
authors.forename: Niu
authors.initials: N
authors.lastname: Huang
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, Hunan Provincial Engineering Research Center of Healthy Livestock, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Institute of Subtropical Agriculture, Chinese Academy of Sciences , Changsha, Hunan 410125, China.|University of the Chinese Academy of Sciences , Beijing 10008, China.
authors.forename: Junquan
authors.initials: J
authors.lastname: Tian
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, Hunan Provincial Engineering Research Center of Healthy Livestock, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Institute of Subtropical Agriculture, Chinese Academy of Sciences , Changsha, Hunan 410125, China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, Hunan Provincial Engineering Research Center of Healthy Livestock, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Institute of Subtropical Agriculture, Chinese Academy of Sciences , Changsha, Hunan 410125, China.
authors.forename: Xihong
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, Hunan Provincial Engineering Research Center of Healthy Livestock, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Institute of Subtropical Agriculture, Chinese Academy of Sciences , Changsha, Hunan 410125, China.|College of Animal Science and Technology, Hunan Agricultural University , Changsha, Hunan 410128, China.
authors.forename: Kang
authors.initials: K
authors.lastname: Yao
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, Hunan Provincial Engineering Research Center of Healthy Livestock, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Institute of Subtropical Agriculture, Chinese Academy of Sciences , Changsha, Hunan 410125, China.|Hunan Co-Innovation Center of Animal Production Safety , Changsha, Hunan 410128, China.
authors.forename: Tiejun
authors.initials: T
authors.lastname: Li
authors.affiliation: Key Laboratory of Agro-ecological Processes in Subtropical Region, Hunan Provincial Engineering Research Center of Healthy Livestock, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Institute of Subtropical Agriculture, Chinese Academy of Sciences , Changsha, Hunan 410125, China.
authors.forename: Yulong
authors.initials: Y
authors.lastname: Yin
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D001120:Arginine / Q000097:blood; D001224:Aspartic Acid / Q000097:blood; D001835:Body Weight; D002952:Citric Acid Cycle / Q000502:physiology; D004032:Diet / Q000662:veterinary; D019587:Dietary Supplements; D020895:Enterocytes / Q000378:metabolism*; D005973:Glutamine / Q000097:blood / Q000378:metabolism*; D007082:Ileum / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D007421:Intestine, Small / Q000378:metabolism; D007532:Isoleucine / Q000097:blood; D007583:Jejunum / Q000378:metabolism; D007656:Ketoglutaric Acids / Q000378:metabolism*; D008239:Lysine / Q000097:blood; D010649:Phenylalanine / Q000097:blood; D012333:RNA, Messenger / Q000378:metabolism; D013552:Swine; D014443:Tyrosine / Q000097:blood; D014633:Valine / Q000097:blood; D014886:Weaning
chemical_list: D000596:Amino Acids; D007656:Ketoglutaric Acids; D012333:RNA, Messenger; D007532:Isoleucine; D005973:Glutamine; D001224:Aspartic Acid; D014443:Tyrosine; D010649:Phenylalanine; D001120:Arginine; D014633:Valine; D008239:Lysine
keywords: alpha-ketoglutarate; amino acids; enterocytes; glutamine; piglet