» Articles » PMID: 27541013

Monomeric ENAMPT in the Development of Experimental Diabetes in Mice: a Potential Target for Type 2 Diabetes Treatment

Overview
Journal Diabetologia
Specialty Endocrinology
Date 2016 Aug 20
PMID 27541013
Citations 19
Authors
Affiliations
Soon will be listed here.
Abstract

Aims/hypothesis: Serum extracellular nicotinamide phosphoribosyltransferase (eNAMPT) concentrations are elevated in type 2 diabetes. However, the relationship between abnormally elevated serum eNAMPT and type 2 diabetes pathophysiology is unclear. eNAMPT circulates in functionally and structurally distinct monomeric and dimeric forms. Dimeric eNAMPT promotes NAD biosynthesis. The role of eNAMPT-monomer is unclear but it may have NAD-independent proinflammatory effects. However, studies of eNAMPT in type 2 diabetes have not distinguished between monomeric and dimeric forms. Since type 2 diabetes is characterised by chronic inflammation, we hypothesised a selective NAD-independent role for eNAMPT-monomer in type 2 diabetes.

Methods: Two mouse models were used to examine the role of eNAMPT-monomer in type 2 diabetes; (1) a mouse model of diabetes fed a high-fat diet (HFD) for 10 weeks received i.p. injections with an anti-monomeric-eNAMPT antibody; and (2) lean non-diabetic mice received i.p. injections with recombinant monomeric eNAMPT daily for 14 days.

Results: Serum monomeric eNAMPT levels were elevated in HFD-fed mouse models of diabetes, whilst eNAMPT-dimer levels were unchanged. eNAMPT-monomer neutralisation in HFD-fed mice resulted in lower blood glucose levels, amelioration of impaired glucose tolerance (IGT) and whole-body insulin resistance, improved pancreatic islet function, and reduced inflammation. These effects were maintained for at least 3 weeks post-treatment. eNAMPT-monomer administration induced a diabetic phenotype in mice, characterised by elevated blood glucose, IGT, impaired pancreatic insulin secretion and the presence of systemic and tissue inflammation, without changes in NAD levels.

Conclusions/interpretation: We demonstrate that elevation of monomeric-eNAMPT plays an important role in the pathogenesis of diet-induced diabetes via proinflammatory mechanisms. These data provide proof-of-concept evidence that the eNAMPT-monomer represents a potential therapeutic target for type 2 diabetes.

Citing Articles

NAD World 3.0: the importance of the NMN transporter and eNAMPT in mammalian aging and longevity control.

Imai S NPJ Aging. 2025; 11(1):4.

PMID: 39870672 PMC: 11772665. DOI: 10.1038/s41514-025-00192-6.


Pathobiochemistry of Aging and Neurodegeneration: Deregulation of NAD+ Metabolism in Brain Cells.

Kolotyeva N, Groshkov A, Rozanova N, Berdnikov A, Novikova S, Komleva Y Biomolecules. 2025; 14(12.

PMID: 39766263 PMC: 11673498. DOI: 10.3390/biom14121556.


Adipokines and their potential impacts on susceptibility to myocardial ischemia/reperfusion injury in diabetes.

Han R, Huang H, Zhu J, Jin X, Wang Y, Xu Y Lipids Health Dis. 2024; 23(1):372.

PMID: 39538244 PMC: 11558907. DOI: 10.1186/s12944-024-02357-w.


Impact of Lipids on Insulin Resistance: Insights from Human and Animal Studies.

Elkanawati R, Sumiwi S, Levita J Drug Des Devel Ther. 2024; 18:3337-3360.

PMID: 39100221 PMC: 11298177. DOI: 10.2147/DDDT.S468147.


NAMPT, IL-6, and vaspin gene expressions and serum protein levels in type 2 diabetes mellitus and related complication.

Celik S, Parilti D, Acik L, Yalcin M, Yetkin I, Yunusov E Turk J Biol. 2024; 48(2):133-141.

PMID: 39051061 PMC: 11265895. DOI: 10.55730/1300-0152.2688.


References
1.
Wang T, Zhang X, Bheda P, Revollo J, Imai S, Wolberger C . Structure of Nampt/PBEF/visfatin, a mammalian NAD+ biosynthetic enzyme. Nat Struct Mol Biol. 2006; 13(7):661-2. DOI: 10.1038/nsmb1114. View

2.
Chen M, Chung F, Chang D, Tsai J, Huang H, Shin S . Elevated plasma level of visfatin/pre-B cell colony-enhancing factor in patients with type 2 diabetes mellitus. J Clin Endocrinol Metab. 2005; 91(1):295-9. DOI: 10.1210/jc.2005-1475. View

3.
Caton P, Nayuni N, Kieswich J, Khan N, Yaqoob M, Corder R . Metformin suppresses hepatic gluconeogenesis through induction of SIRT1 and GCN5. J Endocrinol. 2010; 205(1):97-106. DOI: 10.1677/JOE-09-0345. View

4.
Birkenfeld A, Shulman G . Nonalcoholic fatty liver disease, hepatic insulin resistance, and type 2 diabetes. Hepatology. 2013; 59(2):713-23. PMC: 3946772. DOI: 10.1002/hep.26672. View

5.
Sun K, Kusminski C, Scherer P . Adipose tissue remodeling and obesity. J Clin Invest. 2011; 121(6):2094-101. PMC: 3104761. DOI: 10.1172/JCI45887. View