Related Experiment Video

Updated: Jul 20, 2026

Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes
11:48

Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes

Published on: May 31, 2018

Involvement of MAP kinases in lipopolysaccharide-induced histamine production in RAW 264 cells

Noriyasu Hirasawa1, Masashi Torigoe, Ryohko Ohgawara

  • 1Laboratory of Pathophysiological Biochemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba Aramaki, Aoba-ku, Sendai, Miyagi 980-8578, Japan. hirasawa@mail.pharm.tohoku.ac.jp

Life Sciences
|September 19, 2006
PubMed

Insights

Lipopolysaccharide (LPS) triggers histamine production in mouse RAW 264 cells by increasing histidine decarboxylase (HDC) expression. Mitogen-activated protein (MAP) kinases, particularly p44 and JNK, regulate this LPS-induced HDC upregulation at the transcriptional level.

Area of Science:

  • Immunology
  • Cell Biology
  • Biochemistry

Background:

  • Lipopolysaccharide (LPS) is a potent immune activator.
  • Histamine is a key mediator in inflammatory responses.
  • Mitogen-activated protein (MAP) kinases play crucial roles in cellular signaling pathways.

Purpose of the Study:

  • To investigate the role of MAP kinases in LPS-induced histamine production in RAW 264 cells.
  • To elucidate the signaling pathways involved in regulating histidine decarboxylase (HDC) expression by LPS.

Main Methods:

  • RAW 264 cells were treated with LPS and various MAP kinase inhibitors (U0126, SP600125, SB203580).
  • Histamine levels, HDC mRNA, and 74-kDa HDC protein expression were measured.
  • Phosphorylation of p44/42 MAP kinase, p38 MAP kinase, and c-Jun N-terminal kinase (JNK) was assessed.

Main Results:

  • LPS significantly increased histamine production, HDC mRNA, and 74-kDa HDC protein levels in a dose- and time-dependent manner.
  • LPS induced the phosphorylation of p44/42 MAP kinase, p38 MAP kinase, and JNK.
  • Inhibitors of p44/42 MAP kinase (U0126) and JNK (SP600125) suppressed LPS-induced histamine production and HDC expression.
  • p38 MAP kinase inhibition partially reduced histamine production.

Conclusions:

  • LPS enhances histamine production in RAW 264 cells by upregulating 74-kDa HDC protein expression.
  • MAP kinases, especially p44 MAP kinase and JNK, are critical regulators of LPS-induced HDC expression at the transcriptional level.

More Related Videos

Myeloid Innate Signaling Pathway Regulation by MALT1 Paracaspase Activity07:09

Myeloid Innate Signaling Pathway Regulation by MALT1 Paracaspase Activity

Published on: January 7, 2019

Bone Marrow-derived Macrophage Production07:06

Bone Marrow-derived Macrophage Production

Published on: November 22, 2013

Related Concept Videos

Formation of Lipopolysaccharides01:19

Formation of Lipopolysaccharides

Lipopolysaccharides (LPS) are crucial components of the outer membrane of Gram-negative bacteria, serving both structural and functional roles. It contributes to membrane stability and protects bacteria from host immune responses. LPS is composed of three major regions—lipid A, a core oligosaccharide, and an O antigen. The biosynthesis and assembly of LPS involve a highly coordinated set of enzymatic reactions and transport mechanisms. Additionally, LPS is recognized as an endotoxin, triggering...
MAPK Signaling Cascades01:07

MAPK Signaling Cascades

Mitogen-activated protein kinase, or MAPK pathway, activates three sequential kinases to regulate cellular responses such as proliferation, differentiation, survival, and apoptosis. The canonical MAPK pathway starts with a mitogen or growth factor binding to an RTK. The activated RTKs stimulate Ras, which recruits Raf or MAP3 Kinase (MAPKKK), the first kinase of the MAPK signaling cascade. Raf further phosphorylates and activates MEK or MAP2 Kinases (MAPKK), which in turn phosphorylates MAP...