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Published on: November 23, 2011

Polymorphism in the manganese superoxide dismutase gene

Noha E Elsakka1, Nigel R Webster, Helen F Galley

  • 1Academic Unit of Anaesthesia and Intensive Care, School of Medicine, University of Aberdeen, Aberdeen, UK.

Free Radical Research
|June 20, 2007
PubMed

Insights

The MnSOD Ala9Val polymorphism shows different genotype frequencies in sepsis patients versus healthy individuals. However, this genetic variation had minimal impact on MnSOD enzyme function and cellular response to oxidative stress.

Area of Science:

  • Genetics
  • Molecular Biology
  • Sepsis Pathophysiology

Background:

  • Sepsis involves oxidative stress and mitochondrial damage.
  • Manganese superoxide dismutase (MnSOD) is crucial for mitochondrial antioxidant defense.
  • The MnSOD Ala9Val single nucleotide polymorphism (SNP) may impact enzyme transport and function.

Purpose of the Study:

  • To investigate the association between the MnSOD Ala9Val polymorphism and sepsis.
  • To evaluate the functional consequences of the MnSOD Ala9Val polymorphism on cellular responses.

Main Methods:

  • Genotyping of healthy subjects and sepsis patients.
  • Incubation of peripheral blood mononuclear cells (PBMCs) with lipopolysaccharide (LPS).
  • Analysis of MnSOD activity, cytochrome c concentration, total antioxidant capacity (TAC), and mitochondrial membrane potential in different cellular fractions.

Main Results:

  • A significant difference in MnSOD Ala9Val genotype frequency was observed between healthy individuals and sepsis patients (p = 0.009).
  • No significant differences in MnSOD activity or cytochrome c concentration were found between Ala9Val genotypes.
  • Minor differences in TAC and mitochondrial membrane potential did not alter cellular response to LPS.

Conclusions:

  • The MnSOD Ala9Val polymorphism is associated with sepsis, but exhibits limited functional impact on MnSOD activity and cellular response to oxidative stress.
  • Despite structural predictions, the Ala9Val polymorphism does not significantly alter mitochondrial transport or enzyme function in response to LPS stimulation.

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