Change search
ReferencesLink to record
Permanent link

Direct link
GLP 1 secretion by microglial cells and decreased cns expression in obesity
Stockholm University, Faculty of Science, Department of Neurochemistry.ORCID iD: 0000-0002-6668-1094
Stockholm University, Faculty of Science, Department of Neurochemistry.ORCID iD: 0000-0002-0308-1964
Show others and affiliations
2012 (English)In: Journal of Neuroinflammation, ISSN 1742-2094, Vol. 9, 276- p.Article in journal (Refereed) Published
Abstract [en]

Background: Type 2 diabetes (T2D) is a strong risk factor for developing neurodegenerative pathologies. T2D patients have a deficiency in the intestinal incretin hormone GLP-1, which has been shown to exert neuroprotective and anti-inflammatory properties in the brain. Methods: Here we investigate potential sources of GLP-1 in the CNS and the effect of diabetic conditions on the proglucagon mRNA expression in the CNS. The obese mouse model ob/ob, characterized by its high levels of free fatty acids, and the microglia cell line BV-2 were used as models. mRNA expression and protein secretion were analyzed by qPCR, immunofluorescence and ELISA. Results: We show evidence for microglia as a central source of GLP-1 secretion. Furthermore, we observed that expression and secretion are stimulated by cAMP and dependent on microglial activation state. We also show that insulin-resistant conditions reduce the central mRNA expression of proglucagon. Conclusion: The findings that microglial mRNA expression of proglucagon and GLP-1 protein expression are affected by high levels of free fatty acids and that both mRNA expression levels of proglucagon and secretion levels of GLP-1 are affected by inflammatory stimuli could be of pathogenic importance for the premature neurodegeneration and cognitive decline commonly seen in T2D patients, and they may also be harnessed to advantage in therapeutic efforts to prevent or treat such disorders.

Place, publisher, year, edition, pages
2012. Vol. 9, 276- p.
Keyword [en]
Glucagon-like peptide-1, Microglia, Neuroinflammation, Neuroprotection, Proglucagon
National Category
URN: urn:nbn:se:su:diva-88298DOI: 10.1186/1742-2094-9-276ISI: 000314754300001OAI: diva2:612173


Available from: 2013-03-20 Created: 2013-03-12 Last updated: 2015-03-16Bibliographically approved
In thesis
1. Neuroinflammation in Alzheimer’s disease and obesity
Open this publication in new window or tab >>Neuroinflammation in Alzheimer’s disease and obesity
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Alzheimer’s disease (AD) and obesity are both major problems in the western world. Although they may appear to have little in common at first glance, they are both characterized by chronic inflammation. Exactly how inflammation affects these disorders is far from clear. Microglia, the resident immune cells of the brain, can take on different phenotypes in response to inflammatory stimuli. They can become classically or alternatively activated, where they secrete pro- or anti-inflammatory cytokines respectively. The inflammatory response is to a large part regulated by transcription factors, such as C/EBPδ, which regulate gene expression. The aim of this thesis was to investigate 1) effects of the Alzheimer’s related peptide amyloid-β (Aβ) on C/EBPδ in astrocytes and microglia during inflammatory conditions, 2) how microglia is affected by elevated levels of free fatty acids (FFAs) occurring in obesity and 3) possible cellular sources of the neuroprotective peptide GLP-1 in the brain. In paper I we found that IL-1β-induced C/EBPδ appears to be blocked by Aβ fibrils but not Aβ oligomers in mixed glial cells. In paper II we found that the decreased levels of C/EBPδ were limited to astrocytes under inflammatory conditions and that there was no blocking of IL-1β-induced C/EBPδ in microglia. In paper III we found that the FFA palmitate induces an alternative activation in microglia with no effect on the expression of C/EBPδ or the pro-inflammatory cytokines TNF-α, IL-1β and IL-6. However, pre-exposure to palmitate potentiated microglia phagocytosis and changed the mRNA expression profile of some pro-inflammatory cytokines in response to inflammatory stimuli. In paper IV we found microglia to be a novel source of secreted GLP-1. Further, we found that the GLP-1 secretion could be decreased by inflammatory stimuli. In summary, the inflammatory response of C/EBPδ in AD appears to be disturbed. In addition, palmitate affects the response to inflammatory stimuli in microglia.

Place, publisher, year, edition, pages
Stockholm: Department of Neurochemistry, Stockholm University, 2013. 56 p.
Alzheimer's disease, obesity, neuroinflammation
National Category
Natural Sciences
Research subject
Neurochemistry with Molecular Neurobiology
urn:nbn:se:su:diva-95104 (URN)978-91-7447-731-3 (ISBN)
Public defence
2013-11-22, Magnélisalen, Kemiska övningslaboratoriet, Svante Arrhenius väg 16 B, Stockholm, 13:00 (English)

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 2: Manuscript.

Available from: 2013-10-31 Created: 2013-10-21 Last updated: 2015-03-16Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Tracy, Linda M.Iverfeldt, Kerstin
By organisation
Department of Neurochemistry
In the same journal
Journal of Neuroinflammation

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 48 hits
ReferencesLink to record
Permanent link

Direct link