Superoxide dismutase and pulmonary oxygen toxicity

Area of Science:

• Biochemistry
• Pulmonary Medicine
• Toxicology

Background:

• Three forms of superoxide dismutase (SOD) exist in the lungs: CuZnSOD, MnSOD, and extracellular SOD.
• CuZnSOD and MnSOD are implicated in protecting the lungs against oxygen toxicity.

Purpose of the Study:

• To review the evidence for the protective roles of CuZnSOD and MnSOD against pulmonary oxygen toxicity.
• To highlight methods for enhancing pulmonary SOD levels and their protective effects.

Main Methods:

• Review of existing literature on superoxide dismutase and oxygen toxicity.
• Analysis of studies involving transgenic overexpression of SOD enzymes.
• Examination of studies using liposome-encapsulated or polyethylene glycol-conjugated SOD.

Main Results:

• Overexpression of pulmonary CuZnSOD protects against oxygen toxicity.
• Induction or overexpression of MnSOD also confers protection against oxygen toxicity.
• Methods like transgenic approaches and tracheal insufflation enhance protective SOD levels.

Conclusions:

• CuZnSOD and MnSOD play significant roles in pulmonary defense against oxygen toxicity.
• Strategies to increase lung CuZnSOD and MnSOD levels offer protection.
• The specific role of extracellular SOD in this context remains undetermined.