In vivo and in vitro assessment of brain bioenergetics in aging rats.
Bottom Line: In vivo brain bioenergetics were measured using ³¹P nuclear magnetic resonance (NMR) spectroscopy and in vitro by polarographic analysis of mitochondrial oxidative phosphorylation.When compared to the young controls, a significant decrease of age-dependent mitochondrial respiration and adenosine-3-phosphate (ATP) production measured in vitro correlated with significant reduction of forward creatine kinase reaction (kfor) and with an increase in phosphocreatine (PCr)/ATP, PCr/Pi and PME/ATP ratio measured in vivo.We suppose that mitochondrial dysfunction and oxidative inactivation of endogenous enzymes may participate in age-related disorders of brain energy metabolism.
Affiliation: Pharmacobiochemical Laboratory, Comenius University School of Medicine, Bratislava, Slovakia.Show MeSH
Related in: MedlinePlus
Mentions: Relative concentrations of phosphate metabolism were determined from integrals of their signal in 31P MR spectra using program MESTREC-C 1.5.1 (Table 1 and Fig. 1). Time-dependent 31P MRS saturation transfer was applied to determine the pseudo-first-order rate constant of forward CK reaction (kfor). While the analysis of steady-state 31P MR spectra revealed significant increase in the ratio of PCr/ATP (P < 0.001), PCr/Pi (P < 0.01) and PME/ATP (P < 0.05), we found significant (P < 0.001) decrease of forward kfor in aged rats as compared to the young group.
Affiliation: Pharmacobiochemical Laboratory, Comenius University School of Medicine, Bratislava, Slovakia.