MARCKS phosphorylation and amylase release in GLP-1-stimulated acini isolated from rat pancreas
Little is known about the effects of glucagon-like peptide 1 (GLP-1) on the pancreatic exocrine gland. In the gland, secretagogues induce amylase release. That signal transduction is evoked mainly by an increase in intracellular Ca2+ levels and activation of protein kinase C (PKC). We previously demonstrated that myristoylated alanine-rich C kinase substrate (MARCKS), a PKC substrate, is involved in pancreatic amylase release. Here, we studied the effects of GLP-1 on MARCKS phosphorylation and amylase release in rat pancreatic acini. GLP-1 induced amylase release and MARCKS phosphorylation in isolated pancreatic acini. Inhibitors of cAMP-dependent protein kinase (PKA) suppressed those effects. Furthermore, a MARCKS-related peptide inhibited the GLP-1-induced amylase release. These findings suggest that GLP-1 induces amylase release through MARCKS phosphorylation via activation of PKA in isolated pancreatic acini.
KeywordsGLP-1 MARCKS Amylase PKA Exocytosis
The authors thank Dr. Noriko Koyama (Asahi University School of Dentistry) for helpful advice.
KS conception and design of research; KS, MO, and AM performed experiments; KS, MO, and AM analyzed data; KS, MO, and MK interpreted results of experiments; KS prepared figures; KS drafted manuscript; KS, MO, AM, and MK edited and revised the manuscript; KS, MO, AM, and MK approved final version of manuscript.
This work was supported by JSPS KAKENHI Grant numbers 15K21322 and 15K11060.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflicts of interest.
In accordance with the established related guidelines, the experimental design of the study was approved by the Animal Offices of Asahi University (Approval number: 17-024) and Dokkyo Medical University (Approval numbers: 0876 and 1046).
- 6.Raufman JP, Singh L, Singh G, Eng J (1992) Truncated glucagon-like peptide-1 interacts with exendin receptors on dispersed acini from guinea pig pancreas. Identification of a mammalian analogue of the reptilian peptide exendin-4. J Biol Chem 267:21432–21437Google Scholar
- 8.Wewer Albrechtsen NJ, Albrechtsen R, Bremholm L, Svendsen B, Kuhre RE, Poulsen SS, Christiansen CB, Jensen EP, Janus C, Hilsted L, Deacon CF, Hartmann B, Holst JJ (2016) Glucagon-like peptide 1 receptor signaling in acinar cells causes growth-dependent release of pancreatic enzymes. Cell Rep 17:2845–2856CrossRefGoogle Scholar
- 10.Stumpo DJ, Graff JM, Albert KA, Greengard P, Blackshear PJ (1989) Molecular cloning, characterization, and expression of a cDNA encoding the “80- to 87-kDa” myristoylated alanine-rich C kinase substrate: a major cellular substrate for portion kinase C. Proc Natl Acad Sci U S A 86:4012–4016CrossRefGoogle Scholar
- 12.Satoh K, Matsuki-Fukushima M, Qi B, Guo MY, Narita T, Fujita-Yoshigaki J, Sugiya H (2009) Phosphorylation of myristoylated alanine-rich C kinase substrate is involved in the cAMP-dependent amylase release in parotid acinar cells. Am J Physiol Gastrointest Liver Physiol 296:G1382–G1390CrossRefGoogle Scholar
- 17.Rosé SD, Lejen T, Zhang L, Trifaró JM (2001) Chromaffin cell F-actin disassembly and potentiation of catecholamine release in response to protein kinase C activation by phorbol esters is mediated through myristoylated alanine-rich C kinase substrate. J Biol Chem 276:36757–36763CrossRefGoogle Scholar
- 22.Matozaki T, Williams JA (1989) Multiple sources of 1,2-diacylglycerol in isolated rat pancreatic acini stimulated by cholecystokinin. J Biol Chem 264:14729–14734Google Scholar
- 25.Li M, Li Q, Yang G, Kolosov VP, Perelman JM, Zhou XD (2011) Cold temperature induces mucin hypersecretion from normal human bronchial epithelial cells in vitro through a transient receptor potential melastatin 8 (TRPM8)-mediated mechanism. J Allergy Clin Immunol 128(626–634):e5Google Scholar
- 29.Satoh K, Kashimata M, Sugiya H (2017) Involvement of PLD in β-agonist-induced amylase release via MARCKS phosphorylation in rat parotid acinar cells. J Physiol Sci 67(Suppl):S96Google Scholar
- 31.Satoh K, Kashimata M (2018) Involvement of MARCKS and PLD in parotid and pancreatic amylase release. J Physiol Sci 68(Suppl):S115Google Scholar