title: Muscle coenzyme Q: a potential test for mitochondrial activity and redox status.
abstract: The aim of this study is to determine whether coenzyme Q (CoQ) muscle concentrations and redox state are associated with pathologic changes in muscle biopsy specimens. Skeletal muscle biopsies were collected (January 2002-February 2004) and underwent pathologic evaluation. Quadriceps specimens (n = 47) were stratified accordingly: Group 1, controls without evidence of pathologic abnormalities; Group 2, type I myofiber predominance; Group 3, type II myofiber atrophy; Group 4, lower motor unit disease; and Group 5, muscular dystrophy. Ubiquinol-10, ubiquinone-10, total coenzyme Q10 (CoQ10), coenzyme Q9 (CoQ9), total CoQ (CoQ9+CoQ10) concentrations were analyzed in biopsy muscle by high-performance liquid chromatography. Ubiquinone-10, total CoQ10, and total CoQ concentrations were significantly decreased in Group 5. Significant positive correlations (r congruent with 0.40) were found between muscle ubiquinone-10, total CoQ10, and total CoQ concentrations vs the percentage of myofibers having subsarcolemmal mitochondrial aggregates. CoQ redox ratio and the fraction CoQ9/total CoQ were negatively correlated with subsarcolemmal mitochondrial aggregates. A significant correlation (r = 0.328) also occurred between ubiquinol-10 concentration and citrate synthase activity. This study suggests that total CoQ concentration provides a new method for estimating mitochondrial activity in biopsy muscle; and that the muscle CoQ test is feasible and potentially useful for diagnosing CoQ deficiency states.
authors.affiliation: Division of Pathology and Laboratory Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA.
authors.forename: Lili
authors.initials: L
authors.lastname: Miles
authors.forename: Michael V
authors.initials: MV
authors.lastname: Miles
authors.forename: Peter H
authors.initials: PH
authors.lastname: Tang
authors.forename: Paul S
authors.initials: PS
authors.lastname: Horn
authors.forename: Brenda L
authors.initials: BL
authors.lastname: Wong
authors.forename: Ton J
authors.initials: TJ
authors.lastname: DeGrauw
authors.forename: Paula J
authors.initials: PJ
authors.lastname: Morehart
authors.forename: Kevin E
authors.initials: KE
authors.lastname: Bove
mesh_terms: D000293:Adolescent; D015415:Biomarkers; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008928:Mitochondria / Q000201:enzymology*; D018485:Muscle Fibers, Skeletal / Q000201:enzymology / Q000473:pathology; D018908:Muscle Weakness / Q000378:metabolism / Q000473:pathology; D018482:Muscle, Skeletal / Q000201:enzymology*; D009468:Neuromuscular Diseases / Q000378:metabolism* / Q000473:pathology*; D010084:Oxidation-Reduction; D014451:Ubiquinone / Q000172:deficiency* / Q000378:metabolism
chemical_list: D015415:Biomarkers; D014451:Ubiquinone