Related Experiment Videos
Modulation of NADP(+)-dependent isocitrate dehydrogenase in aging
In Sup Kil1, Young Sup Lee, Young Seuk Bae
1Department of Biochemistry, College of Natural Sciences, Kyungpook National University, Taegu, Korea.
Abstract:
NADPH is an important cofactor in many biosynthesis pathways and the regeneration of reduced glutathione, critically important in cellular defense against oxidative damage. It is mainly produced by glucose-6-phosphate dehydrogenase, malic enzyme, and NADP(+)-specific isocitrate dehydrogenases (ICDHs). Here, we investigated age-related changes in ICDH activity and protein expression in IMR-90 human diploid fibroblast cells and tissues from Fischer 344 rats. We found that in IMR-90 cells the activity of cytosolic ICDH (IDPc) gradually increased with age up to the 46-48 population doubling level (PDL) and then gradually decreased at later PDL. 2',7'-Dichloro-fluorescein fluorescence which reflects intracellular ROS generation was increased with aging in IMR-90 cells. In ad libitum-fed rats, we noted age-related, tissue-specific modulations of IDPc and mitochondrial ICDH (IDPm) activities and protein expression in the liver, kidney and testes. In contrast, ICDH activities and protein expression were not significantly modulated in diet-restricted rats. These data suggest that modulation of ICDH is an age-dependent and a tissue-specific phenomenon.
Related Concept Videos
Mitochondria
Electron Transport Chain: Complex I and II
ROS generation is regulated and maintained at moderate levels necessary...
Role of Reduced Coenzymes NADH and FADH₂
Aging
Cellular Clock Theory
The cellular clock theory posits that the human lifespan is closely tied to the finite capacity of cells to divide, a phenomenon governed by telomeres, which are protective caps at the ends of...