Leucine regulates α-amylase and trypsin synthesis in dairy calf pancreatic tissue in vitro via the mammalian target of rapamycin signalling pathway. (8th January 2019)

• Record Type: Journal Article
• Authors: Guo, L.; Yao, J. H.; Zheng, C.; Tian, H. B.; Liu, Y. L.; Liu, S. M.; Cai, C. J.; Xu, X. R.; Cao, Y. C.
• Is Part Of: Animal. Volume 13:Number 9(2019)
• Page Start: 1899
• Page End: 1906
• Publication Date: 2019-01-08
• Subjects: leucine, -- mammalian target of rapamycin, -- digestive enzymes, -- pancreas; Animal breeding -- Periodicals; Animal genetics -- Periodicals; Animal nutrition -- Periodicals; Animal physiology -- Periodicals; Environmental sciences -- Periodicals; 636.005
• DOI: 10.1017/S1751731118003683
• Languages: English
• ISSNs: 1751-7311

Abstract

Abstract : Starch digestion in the small intestines of the dairy cow is low, to a large extent, due to a shortage of syntheses of α -amylase. One strategy to improve the situation is to enhance the synthesis of α -amylase. The mammalian target of rapamycin (mTOR) signalling pathway, which acts as a central regulator of protein synthesis, can be activated by leucine. Our objectives were to investigate the effects of leucine on the mTOR signalling pathway and to define the associations between these signalling activities and the synthesis of pancreatic enzymes using an in vitro model of cultured Holstein dairy calf pancreatic tissue. The pancreatic tissue was incubated in culture medium containingl -leucine for 3 h, and samples were collected hourly, with the control being included but not containingl -leucine. The leucine supplementation increased α -amylase and trypsin activities and the messenger RNA expression of their coding genes ( P <0.05), and it enhanced the mTOR synthesis and the phosphorylation of mTOR, ribosomal protein S6 kinase 1 and eukaryotic initiation factor 4E-binding protein 1 ( P <0.05). In addition, rapamycin inhibited the mTOR signal pathway factors during leucine treatment. In sum, the leucine regulates α -amylase and trypsin synthesis in dairy calves through the regulation of the mTOR signal pathways.