Oxidative stress decreases with elevation in the lizard Psammodromus algirus.

Area of Science:

• Ecological physiology
• Evolutionary biology
• Environmental science

Background:

• Oxidative stress is a significant ecological and evolutionary factor.
• Geographic variation in environmental stressors leads to differing oxidant environments for organisms.
• Limited data exists on geographical patterns of oxidative damage and antioxidant defenses in animals.

Purpose of the Study:

• To investigate geographical variation in oxidative stress in the lizard *Psammodromus algirus*.
• To compare oxidative stress levels between lizards from lowland and highland environments.

Main Methods:

• Assayed antioxidant enzymatic activity (catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, glutathione transferase, DT-diaphorase) in lizard tail tissue.
• Measured lipid peroxidation levels in lizard tail tissue samples.
• Compared oxidative stress indicators between lowland (300-700 m asl) and highland (2200-2500 m asl) populations.

Main Results:

• Lipid peroxidation was significantly higher in lowland lizards compared to highland lizards.
• Higher lipid peroxidation indicates greater oxidative stress in lowland populations.
• Findings suggest that high-elevation environments are less oxidant than low-elevation environments.

Conclusions:

• Oxidative stress exhibits significant geographical variation in *Psammodromus algirus*.
• Environmental conditions at higher elevations present lower oxidative challenges.
• Geographical differences in oxidative stress have implications for understanding variations in organismal physiology and life history.