Abstract
BackgroundIn the substantia nigra of Parkinson's disease (PD) patients, increased lipid peroxidation, decreased activities of the mitochondrial complex I of the respiratory chain, catalase and glutathione-peroxidase, and decreased levels of reduced glutathione have been reported. These observations suggest that oxidative stress and mitochondrial dysfunction play a role in the neurodegeneration in PD. We assessed enzymatic activities of respiratory chain and other enzymes involved in oxidative processes in skin fibroblasts cultures of patients with PD.MethodsWe studied respiratory chain enzyme activities, activities of total, Cu/Zn- and Mn-superoxide-dismutase, gluthatione-peroxidase and catalase, and coenzyme Q10 levels in skin fibroblasts cultures from 20 Parkinson's disease (PD) patients and 19 age- and sex- matched healthy controls.ResultsWhen compared with controls, PD patients showed significantly lower specific activities for complex V (both corrected by citrate synthase activity and protein concentrations). Oxidized, reduced and total coenzyme Q10 levels (both corrected by citrate synthase and protein concentrations), and activities of total, Cu/Zn- and Mn-superoxide-dismutase, gluthatione-peroxidase and catalase, did not differ significantly between PD-patients and control groups. Values for enzyme activities in the PD group did not correlate with age at onset, duration, scores of the Unified Parkinson's Disease Rating scales and Hoehn-Yahr staging.ConclusionsThe main result of this study was the decreased activity of complex V in PD patients. This complex synthesizes ATP from ADP using an electrochemical gradient generated by complexes I-IV. These results suggest decreased energetic metabolism in fibroblasts of patients with PD.
Highlights
In the substantia nigra of Parkinson’s disease (PD) patients, increased lipid peroxidation, decreased activities of the mitochondrial complex I of the respiratory chain, catalase and glutathione-peroxidase, and decreased levels of reduced glutathione have been reported
PD patients showed significantly lower specific activities for complex V
The main result of the present study in skin fibroblasts cultures suggests a possible contribution of the deficiency of complex V activity, but not of other enzymes related with oxidative stress, to the pathogenesis of PD
Summary
In the substantia nigra of Parkinson’s disease (PD) patients, increased lipid peroxidation, decreased activities of the mitochondrial complex I of the respiratory chain, catalase and glutathione-peroxidase, and decreased levels of reduced glutathione have been reported. These observations suggest that oxidative stress and mitochondrial dysfunction play a role in the neurodegeneration in PD. Four enzymes (complexes I-IV) transport electrons from NADH or succinate to oxygen, Many studies have shown decreased complex I activity in the substantia nigra of PD patients (reviewed in reference [4]). The results of studies measuring mitochondrial complexes in peripheral tissues have been controversial (reviewed in reference [4]). The activity of mitochondrial complexes has been measured in the following tisues:
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
