Catalase activity in blood fractions of patients with sporadic ALS.

Background: Oxidative stress may be a key element in pathogenesis of sporadic amyotrophic lateral sclerosis (sALS). Several studies proved that markers of peroxidation of lipids, proteins or nucleic acids are increased in postmortem tissue of sALS patients. However, much less is known about enzymatic antioxidant defense mechanism in sALS.

Objectives: The aim of the study was to assess catalase (CAT) activity that is implicated in the defense against oxidative stress, in three blood fractions, i.e. erythrocytes, plasma and serum of sALS patients and healthy controls.

Methods: Altogether 46 sALS patients and 54 controls were enrolled in the study. CAT activity was estimated using a commercially available assay kit.

Results: CAT activity in erythrocytes of sALS patients was significantly decreased compared to neurologically healthy controls (p=0.04), whereas CAT activity in plasma and serum was similar in both studied groups.

Conclusions: CAT activity in erythrocytes, in contrast to other blood fractions is reduced in sALS cases as compared to controls, which may indirectly indicate that antioxidant defense system in erythrocytes is involved in pathogenesis of sALS.