Staphylococcal enterotoxin A induces DNA damage in hepatocytes and liver tissues

Toxicon. 2023 Jan 1:221:106980. doi: 10.1016/j.toxicon.2022.106980. Epub 2022 Nov 19.

Abstract

Staphylococcal enterotoxin A (SEA) is a foodborne bacterial toxin that can cause food poisoning, but little research has been done on the DNA damage caused by SEA. The aim of this research was to investigate the action of SEA in inducing DNA damage and oxidative stress response in hepatocytes and liver tissues. After treating HL-7702 and BRL-3A cells with different concentrations of SEA (0, 300, 600 ng/mL and 0, 400, 800 ng/mL), the production of phosphorylated H2AX (γH2AX) and p53 binding protein 1 (53BP1) aggregates was detected by confocal fluorescence microscopy, and the increases in ataxia telangiectasia mutated (ATM), checkpoint kinase 2 (Chk2), p53 protein expression were assessed by Western blot analysis, while increased reactive oxygen species (ROS) content was confirmed by flow cytometry and fluorescence probe. The genotoxicity of SEA to cells was attenuated after the addition of an oxidative inhibitor, demonstrating that SEA induced intracellular DNA damage through the oxidative pathway and a dose-dependent relationship was observed between the oxidation index and SEA. These experimental results deepen our understanding of SEA damage to cells at the genetic level, and provide a new orientation for the prevention and cure of food borne diseases caused by Staphylococcal enterotoxins (SEs).

Keywords: DNA damage; Hepatic injury; Oxidative stress; Staphylococcal enterotoxin A.

MeSH terms

  • Ataxia Telangiectasia Mutated Proteins / genetics
  • Ataxia Telangiectasia Mutated Proteins / metabolism
  • Cell Cycle Proteins* / metabolism
  • DNA Damage
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Enterotoxins / toxicity
  • Hepatocytes / metabolism
  • Liver / metabolism
  • Protein Serine-Threonine Kinases / genetics
  • Protein Serine-Threonine Kinases / metabolism
  • Tumor Suppressor Protein p53* / metabolism
  • Tumor Suppressor Proteins / genetics
  • Tumor Suppressor Proteins / metabolism

Substances

  • Tumor Suppressor Protein p53
  • enterotoxin A, Staphylococcal
  • Ataxia Telangiectasia Mutated Proteins
  • Cell Cycle Proteins
  • Protein Serine-Threonine Kinases
  • Tumor Suppressor Proteins
  • DNA-Binding Proteins
  • Enterotoxins