Phosphatidic acid regulates systemic inflammatory responses by modulating the Akt-mammalian target of rapamycin-p70

Related Experiment Video

Updated: Sep 20, 2026

Development and Application of Rapamycin-regulated Tyrosine Phosphatases
06:56

Development and Application of Rapamycin-regulated Tyrosine Phosphatases

Published on: September 6, 2024

Hyung-Kyu Lim1, Young-Ae Choi, Wan Park

  • 1Department of Biochemistry & Molecular Biology, College of Medicine, Yeungnam University, Daegu 705-717, South Korea.

The Journal of Biological Chemistry
|September 10, 2003
PubMed

Insights

Phosphatidic acid (PA) drives inflammation by promoting the release of pro-inflammatory cytokines and nitric oxide from macrophages. Targeting PA offers a potential therapeutic strategy for inflammatory diseases.

Area of Science:

  • Immunology
  • Cell Biology
  • Biochemistry

Background:

  • Macrophages are key innate immune cells that orchestrate inflammatory responses upon activation.
  • Phosphatidic acid (PA) is a lipid metabolite involved in cell signaling and membrane dynamics.
  • PA has been suggested to play a role as a second messenger in cellular signaling.

Purpose of the Study:

  • To investigate the role of phosphatidic acid (PA) in regulating inflammatory responses.
  • To determine the specific inflammatory mediators influenced by PA.
  • To elucidate the signaling pathways involved in PA-mediated inflammation.

Main Methods:

  • Utilized macrophage Raw264.7 cell line for in vitro studies.
  • Administered PA to mice to assess in vivo effects.
  • Measured levels of cytokines, nitric oxide, and prostaglandin E2.
  • Investigated the Akt/mTOR signaling pathway activation.

Main Results:

  • PA administration increased serum cytokine levels in mice.
  • PA induced the secretion of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) and nitric oxide from macrophages.
  • PA accumulation in macrophages led to Akt-dependent activation of mTOR/p70S6K1.
  • This signaling pathway activation was crucial for inducing inflammatory mediators.

Conclusions:

  • Phosphatidic acid (PA) is a critical regulator of systemic inflammatory responses.
  • PA promotes inflammation through cytokine and nitric oxide production via the Akt/mTOR pathway.
  • PA represents a potential therapeutic target for managing inflammatory conditions.

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