PMID- 22693263 OWN - NLM STAT- MEDLINE DCOM- 20130212 LR - 20131121 IS - 1479-6813 (Electronic) IS - 0952-5041 (Linking) VI - 49 IP - 2 DP - 2012 Oct TI - Rescue of a pathogenic mutant human glucagon receptor by pharmacological chaperones. PG - 69-78 LID - 10.1530/JME-12-0051 [doi] AB - We have previously demonstrated that a homozygous inactivating P86S mutation of the glucagon receptor (GCGR) causes a novel human disease of hyperglucagonemia, pancreatic alpha-cell hyperplasia, and pancreatic neuroendocrine tumors (Mahvash disease). The mechanisms for the decreased activity of the P86S mutant (P86S) are abnormal receptor localization to the endoplasmic reticulum (ER) and defective interaction with glucagon. To search for targeted therapies for Mahvash disease, we examined whether P86S can be trafficked to the plasma membrane by pharmacological chaperones and whether novel glucagon analogs restore effective receptor interaction. We used enhanced green fluorescent protein-tagged P86S stably expressed in HEK 293 cells to allow fluorescence imaging and western blotting and molecular modeling to design novel glucagon analogs in which alanine 19 was replaced with serine or asparagine. Incubation at 27 degrees C largely restored normal plasma membrane localization and normal processing of P86S but osmotic chaperones had no effects. The ER stressors thapsigargin and curcumin partially rescued P86S. The lipophilic GCGR antagonist L-168,049 also partially rescued P86S, so did Cpd 13 and 15 to a smaller degree. The rescued P86S led to more glucagon-stimulated cAMP production and was internalized by glucagon. Compared with the native glucagon, the novel glucagon analogs failed to stimulate more cAMP production by P86S. We conclude that the mutant GCGR is partially rescued by several pharmacological chaperones and our data provide proof-of-principle evidence that Mahvash disease can be potentially treated with pharmacological chaperones. The novel glucagon analogs, however, failed to interact with P86S more effectively. FAU - Yu, Run AU - Yu R AD - Division of Endocrinology and Carcinoid and Neuroendocrine Tumor Center, Cedars-Sinai Medical Center, B-131, 8700 Beverly Boulevard, Los Angeles, California 90048, USA. run.yu@cshs.org FAU - Chen, Chun-Rong AU - Chen CR FAU - Liu, Xiaohong AU - Liu X FAU - Kodra, Janos T AU - Kodra JT LA - eng GR - DK071870/DK/NIDDK NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural PT - Research Support, Non-U.S. Gov't DEP - 20120725 PL - England TA - J Mol Endocrinol JT - Journal of molecular endocrinology JID - 8902617 RN - 0 (L 168049) RN - 0 (Molecular Chaperones) RN - 0 (Pyridines) RN - 0 (Pyrroles) RN - 0 (Receptors, Glucagon) RN - 0 (enhanced green fluorescent protein) RN - 147336-22-9 (Green Fluorescent Proteins) RN - 452VLY9402 (Serine) RN - 67526-95-8 (Thapsigargin) RN - 7006-34-0 (Asparagine) RN - 9007-92-5 (Glucagon) RN - E0399OZS9N (Cyclic AMP) RN - IT942ZTH98 (Curcumin) RN - OF5P57N2ZX (Alanine) SB - IM MH - Alanine/chemistry MH - Asparagine/chemistry MH - Cell Membrane/metabolism MH - Curcumin/pharmacology MH - Cyclic AMP/metabolism MH - Drug Design MH - Glucagon/*analogs & derivatives MH - Green Fluorescent Proteins/genetics/metabolism MH - HEK293 Cells MH - Humans MH - Molecular Chaperones/metabolism/pharmacology MH - *Mutation MH - Pancreatic Neoplasms/genetics MH - Protein Transport/*drug effects MH - Pyridines MH - Pyrroles MH - Receptors, Glucagon/antagonists & inhibitors/*genetics/*metabolism MH - Serine/chemistry MH - Thapsigargin/pharmacology EDAT- 2012/06/14 06:00 MHDA- 2013/02/13 06:00 CRDT- 2012/06/14 06:00 PHST- 2012/06/14 06:00 [entrez] PHST- 2012/06/14 06:00 [pubmed] PHST- 2013/02/13 06:00 [medline] AID - JME-12-0051 [pii] AID - 10.1530/JME-12-0051 [doi] PST - epublish SO - J Mol Endocrinol. 2012 Jul 25;49(2):69-78. doi: 10.1530/JME-12-0051. Print 2012 Oct.