Histamine modulates hippocampal inflammation and neurogenesis in adult mice

Sci Rep. 2019 Jun 10;9(1):8384. doi: 10.1038/s41598-019-44816-w.

Abstract

Evidence points to a dual role of histamine in microglia-mediated neuroinflammation, a key pathological feature of several neurodegenerative pathologies. Moreover, histamine has been suggested as a modulator of adult neurogenesis. Herein, we evaluated the effect of histamine in hippocampal neuroinflammation and neurogenesis under physiological and inflammatory contexts. For that purpose, mice were intraperitoneally challenged with lipopolysaccharide (LPS) followed by an intrahippocampal injection of histamine. We showed that histamine per se triggered glial reactivity and induced mild long-term impairments in neurogenesis, reducing immature neurons dendritic volume and complexity. Nevertheless, in mice exposed to LPS (2 mg/Kg), histamine was able to counteract LPS-induced glial activation and release of pro-inflammatory molecules as well as neurogenesis impairment. Moreover, histamine prevented LPS-induced loss of immature neurons complexity as well as LPS-induced loss of both CREB and PSD-95 proteins (essential for proper neuronal activity). Altogether, our results highlight histamine as a potential therapeutic agent to treat neurological conditions associated with hippocampal neuroinflammation and neurodegeneration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cyclic AMP Response Element-Binding Protein / genetics
  • Disease Models, Animal
  • Disks Large Homolog 4 Protein / genetics
  • Gene Expression Regulation / drug effects
  • Hippocampus / drug effects
  • Hippocampus / pathology
  • Histamine / pharmacology*
  • Humans
  • Inflammation / chemically induced
  • Inflammation / drug therapy*
  • Inflammation / genetics
  • Inflammation / pathology
  • Lipopolysaccharides / toxicity
  • Mice
  • Microglia / drug effects
  • Neurogenesis / drug effects*
  • Neurons / drug effects*
  • Neurons / metabolism
  • Neurons / pathology

Substances

  • Creb1 protein, mouse
  • Cyclic AMP Response Element-Binding Protein
  • Disks Large Homolog 4 Protein
  • Dlg4 protein, mouse
  • Lipopolysaccharides
  • Histamine