TY - JOUR
T1 - Biochemical parameters for the diagnosis of mitochondrial respiratory chain deficiency in humans, and their lack of age-related changes
AU - Chretien, Dominique
AU - Gallego, Jorge
AU - Barrientos, Antoni
AU - Casademont, Jordi
AU - Cardellach, Francesc
AU - Munnich, Arnold
AU - Rötig, Agnès
AU - Rustin, Pierre
PY - 1998/1/15
Y1 - 1998/1/15
N2 - It is now widely acknowledged that a large number of human diseases originate from respiratory-chain dysfunctions. Because the molecular bases of these diseases are still poorly known, a biochemical approach has to be used in the screening procedures for the diagnoses of these conditions. Assessment of respiratory-chain function in human samples faces several problems: (i) the small size of available samples, (ii) the determination of discriminating parameters, and (iii) the interfering factors, such as age and physical activity. The present study focuses on isolated mitochondria prepared from a minute amount (100-200 mg) of skeletal-muscle biopsies from 201 patients between 0 and 65 years. Whereas 42 patients presented an isolated complex (C)I, CII, CIII or CIV deficiency, no respiratory-chain dysfunction or indirect evidence for a mitochondrial disorder could be attested in 159 of these patients. In this reference group, there was little correlation between enzyme activities and age, whatever the age class considered, 0-3 or 0-65 years of age. However, a confident handling of data points was largely hampered by the marked scattering of enzyme activities measured in the reference population. Activity ratios between the various respiratory-chain complexes presenting a much reduced scattering may be considered as diagnostic tools. As to the effect of age, no correlation with any of the enzyme-activity ratios could be shown. Use of age-matched controls for the diagnosis of respiratory-chain disorders may therefore be avoided, enzyme-activity ratios being highly discriminating and age-independent parameters.
AB - It is now widely acknowledged that a large number of human diseases originate from respiratory-chain dysfunctions. Because the molecular bases of these diseases are still poorly known, a biochemical approach has to be used in the screening procedures for the diagnoses of these conditions. Assessment of respiratory-chain function in human samples faces several problems: (i) the small size of available samples, (ii) the determination of discriminating parameters, and (iii) the interfering factors, such as age and physical activity. The present study focuses on isolated mitochondria prepared from a minute amount (100-200 mg) of skeletal-muscle biopsies from 201 patients between 0 and 65 years. Whereas 42 patients presented an isolated complex (C)I, CII, CIII or CIV deficiency, no respiratory-chain dysfunction or indirect evidence for a mitochondrial disorder could be attested in 159 of these patients. In this reference group, there was little correlation between enzyme activities and age, whatever the age class considered, 0-3 or 0-65 years of age. However, a confident handling of data points was largely hampered by the marked scattering of enzyme activities measured in the reference population. Activity ratios between the various respiratory-chain complexes presenting a much reduced scattering may be considered as diagnostic tools. As to the effect of age, no correlation with any of the enzyme-activity ratios could be shown. Use of age-matched controls for the diagnosis of respiratory-chain disorders may therefore be avoided, enzyme-activity ratios being highly discriminating and age-independent parameters.
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U2 - 10.1042/bj3290249
DO - 10.1042/bj3290249
M3 - Article
C2 - 9425106
AN - SCOPUS:0032518849
VL - 329
SP - 249
EP - 254
JO - Biochemical Journal
JF - Biochemical Journal
SN - 0264-6021
IS - 2
ER -