Decreased cerebrospinal fluid cytochrome c levels in patients with amyotrophic lateral sclerosis

There is evidence showing impaired mitochondrial energy production and increased oxidative damage to mitochondria in amyotrophic lateral sclerosis (ALS). It is known that a lack of cytochrome c (CyC) in the mitochondrial intermembrane space can increase free radical release from mitochondria through interruption of the electron transport. CyC also plays a role in the apoptotic cell death which is suspected in ALS. The aim of the study was to measure cerebrospinal fluid (CSF) and serum CyC levels in patients with ALS.

Forty ALS patients were diagnosed according to the El Escorial criteria of ALS. The clinical state of the patients was measured using the Amyotrophic Lateral Sclerosis Functional Rating Scale [ALSFRS].

It was shown that overall CyC levels were significantly decreased by 46 % in the CSF of patients with ALS compared with controls (p<0.05), and not affected in serum of patients with ALS (p>0.05). There was no significant difference in CyC levels in relation to the clinical parameters of the disease (p>0.05).

The study indicates that CyC may play a role in the pathogenesis of ALS. A possible mechanism is that increased neurodegeneration in ALS caused by free radical production decreases the concentrations of CyC.