title: Age-dependent alterations in mitochondrial enzymes in cortex, striatum and hippocampus of rat brain -- potential role of L-Carnitine.
abstract: Mitochondria link the energy -- releasing activities of electron transport and proton pumping with the energy conserving process of oxidative phosphorylation to form ATP. A declined mitochondrial performance has been generally observed during aging. In the present investigation, the activities of tricarboxylic acid cycle enzymes such as isocitrate, alpha-ketoglutarate, succinate and malate dehydrogenases and electron transport complexes I-IV were measured in mitochondria isolated from brain regions like cortex, striatum and hippocampus of young and aged rats before and after L-Carnitine supplementation. All the three brain regions of aged rats showed decreased activities of isocitrate, alpha-ketoglutarate and succinate dehydrogenases, complexes I and IV when compared to control young rats. Striatum seems to be the most susceptible region when compared to hippocampus and cortex. L-Carnitine supplementation to aged rats reversed the activities of these enzymes to near normal whereas treatment to young rats did not show any significant alterations. These results confirm that L-Carnitine can alleviate the age-associated decline in the metabolic efficiency of mitochondria in all three brain regions under investigation.
authors.affiliation: Department of Medical Biochemistry, Dr AL Mudaliar Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai 600 113, India.
authors.forename: Dayalan
authors.initials: D
authors.lastname: Haripriya
authors.forename: Muthuswamy Anusuya
authors.initials: MA
authors.lastname: Devi
authors.forename: Vedagiri
authors.initials: V
authors.lastname: Kokilavani
authors.forename: Purushotham
authors.initials: P
authors.lastname: Sangeetha
authors.forename: Chinnakannu
authors.initials: C
authors.lastname: Panneerselvam
mesh_terms: D000375:Aging / Q000378:metabolism*; D000818:Animals; D002331:Carnitine / Q000008:administration & dosage*; D002540:Cerebral Cortex / Q000201:enzymology*; D003342:Corpus Striatum / Q000201:enzymology*; D006624:Hippocampus / Q000201:enzymology*; D008297:Male; D008928:Mitochondria / Q000201:enzymology; D051381:Rats; D017208:Rats, Wistar
chemical_list: D002331:Carnitine