Cited by 226Neuroinflammation and Neurodegeneration MechanismsGrowth Hormone and Insulin-like Growth FactorsNeurogenesis and neuroplasticity mechanisms

Insulin-like growth factor 1 and 2 (IGF1, IGF2) expression in human microglia: differential regulation by inflammatory mediators

Open access
Suh, Hyeon-Sook, Zhao, Meng-Liang, Derico, Leandra, Choi, Namjong, Lee, Sunhee C·2013·Journal of Neuroinflammation

Abstract

BACKGROUND: Recent studies in experimental animals show that insulin-like growth factor 1 (IGF1) plays a trophic role during development and tissue injury and that microglia are important sources of IGF1. However, little information is available regarding the expression, regulation, and function of IGF1 and related proteins in human brain cells. In the current study, we examined the expression of IGF1 and IGF2 in human microglia in vivo and in vitro. METHODS: Expression of IGF1 and IGF2 was examined by immunohistochemistry in post-mortem human brain sections derived from HIV+ and HIV- brains. In primary cultures of human fetal microglia, IGF1 and IGF2 mRNA and protein expression was examined by Q-PCR, ELISA, and Western blot analysis. Additionally, the role of IGF1 and IGF2 in neuroprotection was examined in primary human neuronal glial cultures. RESULTS: Immunohistochemistry of human brain tissues showed that nonparenchymal cells (vessels and meninges), as well as parenchymal microglia and macrophages were positive for IGF1, in both HIV encephalitis and control brains, while IGF2 was undetectable. Cultured microglia expressed IGF1 mRNA and produced pg/ml levels of IGF1 protein; this was significantly suppressed by proinflammatory mediators, such as lipopolysaccharide (LPS), poly(I:C), and IFNγ. The Th2 cytokines IL-4 and IL-13 had no significant effect, but the cAMP analog (dibutyryl cAMP) significantly increased IGF1 production. In contrast, microglial IGF2 mRNA and protein (determined by Western blot) were upregulated by LPS. IGF1 receptor (IGF1R) immunoreactivity was predominantly expressed by neurons, and both IGF1 and IGF2 significantly protected neurons from cytokine (IL-1/IFNγ) induced death. CONCLUSIONS: Our study in human brain tissues and cells indicates that microglia are important sources of neurotrophic growth factors IGF1 and IGF2, and that microglial activation phenotypes can influence the growth factor expression. Importantly, our results suggest that chronic neuroinflammation and upregulation of proinflammatory cytokines could lead to neurodegeneration by suppressing the production of microglia-derived neuronal growth factors, such as IGF1.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1186/1742-2094-10-37

Cites

68 of 68 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Cited by

Sorted by citations

Authors
Suh, H.-S., Zhao, M.-L., Derico, L., Choi, N., & Lee, S. C.
Affiliations
Albert Einstein College of Medicine (US)
Corresponding author
  • Suh, Hyeon-Sook
  • Lee, Sunhee C
Venue
Journal of Neuroinflammation
Published
2013-03-12
Volume
10
Issue
1
Pages
37-37
ISSN
1742-2094 (ISSN-L)
OpenAlex
W2138293945
Cited by
226
References
68
Citations by year
2026: 5 · 2025: 7 · 2024: 23 · 2023: 20 · 2022: 26 · 2021: 30 · 2020: 17 · 2019: 15 · 2018: 12 · 2017: 20 · 2016: 15 · 2015: 15 · 2014: 14 · 2013: 7
FWCI
9.54
Type
journal article
Language
en
Open access
Locations
  • Journal of Neuroinflammation (publishedVersion, cc-by)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
Funders
  • National Institutes of Health
  • National Institute of Mental Health (R01MH055477, KO1MH084705, R01 MH 55477, K01MH084705)
  • National Institute of Allergy and Infectious Diseases (P30AI051519)
Topics
  • Life Sciences › Neuroscience › Neurology › Neuroinflammation and Neurodegeneration Mechanisms
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Growth Hormone and Insulin-like Growth Factors
  • Life Sciences › Neuroscience › Developmental Neuroscience › Neurogenesis and neuroplasticity mechanisms
Keywords
insulin-like growth factor I, insulin-like growth factor II, microglia, neuroinflammation, HIV-associated encephalitis, neuroprotection, IGF-1 receptor, inflammatory cytokines, lipopolysaccharide, interferon-gamma, cAMP signaling, neurodegeneration, human brain, neuronal growth factors, microglial activation, macrophages
MeSH terms
Cells, Cultured, Gene Expression Regulation, Humans, Insulin-Like Growth Factor I, Insulin-Like Growth Factor II, Neuroglia, Neurons, Phenotype, Microglia, Inflammation Mediators, Coculture Techniques

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review