KDM2B regulates inflammation and oxidative stress of sepsis via targeting NF-κB and AP-1 pathways

Xin Li1, Xinyu Tian1, Dongliang Zhang1

  • 1Department of Nephrology, Beijing Jishuitan Hospital, Capital Medical University, Beijing, China.

PubMed
Abstract

Insights

Lysine-specific demethylase 2B (KDM2B) knockdown protects against sepsis-induced acute kidney injury (AKI) by reducing inflammation and oxidative stress. This suggests KDM2B is a potential therapeutic target for treating sepsis-associated AKI.

Area of Science:

  • Nephrology
  • Molecular Biology
  • Sepsis Research

Background:

  • Sepsis frequently causes acute kidney injury (AKI), a significant clinical challenge.
  • Histone-modifying enzyme lysine-specific demethylase 2B (KDM2B) is implicated in various pathologies, but its role in sepsis-induced AKI remains unknown.

Purpose of the Study:

  • To investigate the function of KDM2B in cell viability, inflammation, and oxidative stress in sepsis-associated AKI.
  • To elucidate the signaling pathways involved in KDM2B's role in sepsis-induced AKI.

Main Methods:

  • An in vitro acute kidney injury (AKI) model was created using lipopolysaccharide (LPS)-induced HK-2 cells.
  • Key protein and gene expressions (KDM2B, COX2, iNOS, NF-κB, AP-1 pathway components) were analyzed using Western blot and qPCR.
  • Cell viability, cytotoxicity (LDH release), and levels of inflammatory mediators, oxidative stress markers (TNF-α, IL-1β, IL-18, VCAM-1, SOD, MDA, GSH, H₂O₂), were quantified via CCK-8 assay and ELISA.

Main Results:

  • KDM2B knockdown significantly improved cell viability and reduced cytotoxicity and LDH release in LPS-induced AKI.
  • Reduced KDM2B expression decreased the levels and transcription of pro-inflammatory molecules (TNF-α, IL-1β, IL-18, VCAM-1).
  • KDM2B knockdown mitigated oxidative stress by increasing antioxidant markers (SOD, GSH) and decreasing oxidative damage markers (MDA, H₂O₂), while also reducing COX2 and iNOS expression. KDM2B activation of NF-κB and AP-1 pathways was implicated in LPS-induced HK-2 cell injury.

Conclusions:

  • KDM2B knockdown ameliorates cytotoxicity, inflammation, and oxidative stress in a model of sepsis-induced AKI.
  • Inhibition of NF-κB and AP-1 signaling pathways mediates the protective effects of KDM2B knockdown.
  • KDM2B represents a potential therapeutic target for managing sepsis-associated AKI.

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