Short-term caloric restriction and sites of oxygen radical generation in kidney and skeletal muscle mitochondria.
Mitochondrial free radical generation is believed to be one of the principal factors determining aging rate, and complexes I and III have been described as the main sources of reactive oxygen species (ROS) within mitochondria in heart, brain, and liver. Moreover, complex I ROS generation of heart and liver mitochondria seems especially linked to aging rate both in comparative studies between animals with different longevities and in caloric restriction models. Caloric restriction (CR) is a well-documented manipulation that extends mean and maximum longevity. One of the factors that appears to be involved in such life span extension is the reduction in mitochondrial free radical generation at complex I. We have performed two parallel investigations, one studying the effect of short-term CR on oxygen radical generation in kidney and skeletal muscle (gastrocnemius) mitochondria and a second one regarding location of mitochondrial ROS-generating sites in these same tissues. In the former study, no effect of short-term caloric restriction was observed in mitochondrial free radical generation in either kidney or skeletal muscle. The latter study ruled out complex II as a principal source of free radicals in kidney and in skeletal muscle mitochondria, and, similar to previous investigations in heart and liver organelles, the main free radical generators were located at complexes I and III within the electron transport system.
Gredilla
Ricardo
R
Department of Animal Biology-II (Animal Physiology), Faculty of Biology, Complutense University, 28040 Madrid, Spain.
Phaneuf
Sharon
S
Selman
Colin
C
Kendaiah
Suma
S
Leeuwenburgh
Christiaan
C
Barja
Gustavo
G
D000375:Aging; D000818:Animals; D031204:Caloric Restriction; D004579:Electron Transport; D005609:Free Radicals; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007668:Kidney / Q000378:metabolism*; D008136:Longevity; D008297:Male; D008928:Mitochondria / Q000473:pathology*; D018482:Muscle, Skeletal / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption; D051381:Rats; D011916:Rats, Inbred F344; D017382:Reactive Oxygen Species
D005609:Free Radicals; D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide; D010100:Oxygen