PMID- 28571990
OWN - NLM
STAT- MEDLINE
DCOM- 20180427
LR  - 20211204
IS  - 1525-3198 (Electronic)
IS  - 0022-0302 (Linking)
VI  - 100
IP  - 8
DP  - 2017 Aug
TI  - Optimal ratios of essential amino acids stimulate beta-casein synthesis via 
      activation of the mammalian target of rapamycin signaling pathway in MAC-T cells 
      and bovine mammary tissue explants.
PG  - 6676-6688
LID - S0022-0302(17)30543-X [pii]
LID - 10.3168/jds.2017-12681 [doi]
AB  - Amino acids are the building blocks of proteins and serve as key molecular 
      components upstream of the signaling pathways that regulate protein synthesis. 
      The objective of this study was to systematically investigate the effect of 
      essential AA ratios on milk protein synthesis in vitro and to elucidate some of 
      the underlying mechanisms. Triplicate cultures of MAC-T cells and bovine mammary 
      tissue explants (MTE) were incubated with the optimal AA ratio (OPAA; Lys:Met, 
      2.9:1; Thr:Phe, 1.05:1; Lys:Thr, 1.8:1; Lys:His, 2.38:1; and Lys:Val, 1.23:1) in 
      the presence of rapamycin (control), OPAA, a Lys:Thr ratio of 2.1:1, a Lys:Thr 
      ratio of 1.3:1, a Lys:His ratio of 3.05:1, or a Lys:Val ratio of 1.62:1 for 12 h; 
      the other AA concentrations were equal to OPAA. In some experiments, the cells 
      were cultured with OPAA with or without rapamycin (100 ng/mL) or with mammalian 
      target of rapamycin (mTOR) small interference RNA, and the MTE were exposed to 
      OPAA with rapamycin for beta-casein expression. Among the treatments, the expression 
      of beta-casein was greatest in the MTE cultured with OPAA. In MAC-T cells, the OPAA 
      upregulated the mRNA expression of SLC1A5 and SLC7A5 but downregulated the 
      expression of IRS1, AKT3, EEF1A1, and EEF2 compared with the control. The OPAA 
      had no effect on the mTOR phosphorylation status but increased the 
      phosphorylation of S6K1 and RPS6. When the MTE were treated with rapamycin in the 
      presence of OPAA, the expression of beta-casein was markedly decreased. The 
      phosphorylation of RPS6 and 4EBP1 also was reduced in MAC-T cells. A similar 
      negative effect on the expression of RPS6KB1 and EIF4EBP1 was detected when the 
      cells were cultured with either rapamycin or mTOR small interference RNA. The 
      optimal AA ratio stimulated beta-casein expression partly by enhancing the transport 
      of AA into the cells, cross-talk with insulin signaling and a subsequent 
      enhancement of mTOR signaling, or translation elongation in both MAC-T cells and 
      bovine MTE.
CI  - Copyright (c) 2017 American Dairy Science Association. Published by Elsevier Inc. 
      All rights reserved.
FAU - Li, S S
AU  - Li SS
AD  - Institute of Dairy Science, College of Animal Sciences, MoE Key Laboratory of 
      Molecular Animal Nutrition, Zhejiang University, Hangzhou 310058, P. R. China.
FAU - Loor, J J
AU  - Loor JJ
AD  - Mammalian NutriPhysioGenomics, Department of Animal Sciences and Division of 
      Nutritional Sciences, University of Illinois, Urbana 61801. Electronic address: 
      jloor@illinois.edu.
FAU - Liu, H Y
AU  - Liu HY
AD  - Institute of Dairy Science, College of Animal Sciences, MoE Key Laboratory of 
      Molecular Animal Nutrition, Zhejiang University, Hangzhou 310058, P. R. China.
FAU - Liu, L
AU  - Liu L
AD  - Institute of Dairy Science, College of Animal Sciences, MoE Key Laboratory of 
      Molecular Animal Nutrition, Zhejiang University, Hangzhou 310058, P. R. China.
FAU - Hosseini, A
AU  - Hosseini A
AD  - Mammalian NutriPhysioGenomics, Department of Animal Sciences and Division of 
      Nutritional Sciences, University of Illinois, Urbana 61801.
FAU - Zhao, W S
AU  - Zhao WS
AD  - Mammalian NutriPhysioGenomics, Department of Animal Sciences and Division of 
      Nutritional Sciences, University of Illinois, Urbana 61801.
FAU - Liu, J X
AU  - Liu JX
AD  - Institute of Dairy Science, College of Animal Sciences, MoE Key Laboratory of 
      Molecular Animal Nutrition, Zhejiang University, Hangzhou 310058, P. R. China. 
      Electronic address: liujx@zju.edu.cn.
LA  - eng
PT  - Journal Article
DEP - 20170530
PL  - United States
TA  - J Dairy Sci
JT  - Journal of dairy science
JID - 2985126R
RN  - 0 (Amino Acids)
RN  - 0 (Amino Acids, Essential)
RN  - 0 (Caseins)
RN  - EC 2.7.11.1 (TOR Serine-Threonine Kinases)
RN  - W36ZG6FT64 (Sirolimus)
SB  - IM
MH  - Amino Acids
MH  - Amino Acids, Essential/*administration & dosage
MH  - Animals
MH  - Caseins/*biosynthesis
MH  - Cattle
MH  - Female
MH  - Mammary Glands, Animal/*cytology
MH  - Phosphorylation
MH  - Signal Transduction
MH  - Sirolimus
MH  - T-Lymphocytes
MH  - TOR Serine-Threonine Kinases/*metabolism
OTO - NOTNLM
OT  - MAC-T cell
OT  - bovine mammary tissue explant
OT  - mammalian target of rapamycin
OT  - milk protein synthesis
OT  - signaling protein
EDAT- 2017/06/03 06:00
MHDA- 2018/04/28 06:00
CRDT- 2017/06/03 06:00
PHST- 2017/02/02 00:00 [received]
PHST- 2017/04/17 00:00 [accepted]
PHST- 2017/06/03 06:00 [pubmed]
PHST- 2018/04/28 06:00 [medline]
PHST- 2017/06/03 06:00 [entrez]
AID - S0022-0302(17)30543-X [pii]
AID - 10.3168/jds.2017-12681 [doi]
PST - ppublish
SO  - J Dairy Sci. 2017 Aug;100(8):6676-6688. doi: 10.3168/jds.2017-12681. Epub 2017 
      May 30.