Abstract | CONTEXT: Type 2 Wolfram syndrome (T2-WFS) is a neuronal and β-cell degenerative disorder caused by mutations in the CISD2 gene. The mechanisms underlying β-cell dysfunction in T2-WFS are not known, and treatments that effectively improve diabetes in this context are lacking. OBJECTIVE: Unraveling the mechanisms of β-cell dysfunction in T2-WFS and the effects of treatment with GLP-1 receptor agonist (GLP-1-RA). DESIGN AND SETTING: A case report and in vitro mechanistic studies. PATIENT AND METHODS: We treated an insulin-dependent T2-WFS patient with the GLP-1-RA exenatide for 9 weeks. An iv glucose/ glucagon/ arginine stimulation test was performed off- drug before and after intervention. We generated a cellular model of T2-WFS by shRNA knockdown of CISD2 (nutrient-deprivation autophagy factor-1 [NAF-1]) in rat insulinoma cells and studied the mechanisms of β-cell dysfunction and the effects of GLP-1-RA. RESULTS: Treatment with exenatide resulted in a 70% reduction in daily insulin dose with improved glycemic control, as well as an off- drug 7-fold increase in maximal insulin secretion. NAF-1 repression in INS-1 cells decreased insulin content and glucose-stimulated insulin secretion, while maintaining the response to cAMP, and enhanced the accumulation of labile iron and reactive oxygen species in mitochondria. Remarkably, treatment with GLP-1-RA and/or the iron chelator deferiprone reversed these defects. CONCLUSION: NAF-1 deficiency leads to mitochondrial labile iron accumulation and oxidative stress, which may contribute to β-cell dysfunction in T2-WFS. Treatment with GLP-1-RA and/or iron chelation improves mitochondrial function and restores β-cell function. Treatment with GLP-1-RA, probably aided by iron chelation, should be considered in WFS and other forms of diabetes associated with iron dysregulation.
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Authors | Liron Danielpur, Yang-Sung Sohn, Ola Karmi, Chen Fogel, Adar Zinger, Abdulsalam Abu-Libdeh, Tal Israeli, Yael Riahi, Orit Pappo, Ruth Birk, David H Zangen, Ron Mittler, Zvi-Ioav Cabantchik, Erol Cerasi, Rachel Nechushtai, Gil Leibowitz |
Journal | The Journal of clinical endocrinology and metabolism
(J Clin Endocrinol Metab)
Vol. 101
Issue 10
Pg. 3592-3599
(10 2016)
ISSN: 1945-7197 [Electronic] United States |
PMID | 27459537
(Publication Type: Case Reports, Journal Article)
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Chemical References |
- Glucagon-Like Peptide-1 Receptor
- Hypoglycemic Agents
- Peptides
- Venoms
- Exenatide
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Topics |
- Aging, Premature
(drug therapy)
- Animals
- Exenatide
- Female
- Glucagon-Like Peptide-1 Receptor
(agonists)
- Hearing Loss, Sensorineural
(drug therapy)
- Humans
- Hypoglycemic Agents
(administration & dosage, pharmacology)
- Insulin-Secreting Cells
(drug effects)
- Mitochondria
(drug effects)
- Mitochondrial Diseases
(drug therapy)
- Optic Atrophy
(drug therapy)
- Peptides
(administration & dosage, pharmacology)
- Rats
- Venoms
(administration & dosage, pharmacology)
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