Microgravity activates p38 MAPK-C/EBPβ pathway to regulate the expression of arginase and inflammatory cytokines in

Chongzhen Wang1, Hui Chen, Haiying Luo

  • 1Transplantation Biology Research Division, State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beichen West Road 1-5, Chaoyang District, Beijing, 100101, China.

Abstract

Insights

Simulated microgravity increases arginase and IL-6 while decreasing IL-12B in macrophages via the p38 MAPK-C/EBPβ pathway, contributing to immune suppression.

Area of Science:

  • Immunology
  • Space Biology
  • Cellular Biology

Background:

  • Microgravity's impact on immune function is not fully understood.
  • Macrophages play a critical role in immune responses.
  • Investigating cellular mechanisms is key to understanding spaceflight effects.

Purpose of the Study:

  • To explore simulated microgravity's effects on macrophage function.
  • To identify intracellular signaling pathways involved.

Main Methods:

  • Primary mouse macrophages cultured under simulated microgravity (RCCS-1) and 1g control.
  • Gene expression and protein levels analyzed using real-time PCR and western blots.
  • Flow cytometry used to assess cellular functions and signaling.

Main Results:

  • Simulated microgravity significantly increased arginase mRNA and protein levels.
  • Over-expression of C/EBPβ and activation of p38 MAPK were observed.
  • Interleukin-6 (IL-6) was upregulated, and IL-12 p40 (IL-12B) was downregulated.

Conclusions:

  • A p38 MAPK-C/EBPβ pathway is activated by simulated microgravity in macrophages.
  • This pathway modulates arginase, IL-6, and IL-12B expression.
  • Altered macrophage function under microgravity may lead to immunosuppression.