Low brain intracellular free magnesium in mitochondrial cytopathies

Bruno Barbiroli, Stefano Iotti, Pietro Cortelli, Paolo Martinelli, Raffaele Lodi, Valerio Carelli, Pasquale Montagna

Research output: Contribution to journalArticle

Abstract

The authors studied, by in vivo phosphorus magnetic resonance spectroscopy (31P-MRS), the occipital lobes of 19 patients with mitochondrial cytopathies to clarify the functional relation between energy metabolism and concentration of cytosolic free magnesium. All patients displayed defective mitochondrial respiration with low phosphocreatine concentration [PCr] and high inorganic phosphate concentration [Pi] and [ADP]. Cytosolic free [Mg2+] and the readily available free energy (defined as the actual free energy released by the exoergonic reaction of ATP hydrolysis, i.e., ΔG(ATPhyd)) were abnormally low in all patients. Nine patients were treated with coenzyme Q10 (CoQ), which improved the efficiency of the respiratory chain, as shown by an increased [PCr], decreased [Pi] and [ADP], and increased availability of free energy (more negative value of ΔG(ATPhyd)). Treatment with CoQ also increased cytosolic free [Mg2+] in all treated patients. The authors findings demonstrate low brain free [Mg2+] in our patients and indicate that it resulted from failure of the respiratory chain. Free Mg2+ contributes to the absolute value of ΔG(ATPhyd). The results also are consistent with the view that cytosolic [Mg2+] is regulated in the intact brain cell to equilibrate, at least in part, any changes in rapidly available free energy.

Original languageEnglish
Pages (from-to)528-532
Number of pages5
JournalJournal of Cerebral Blood Flow and Metabolism
Volume19
Issue number5
Publication statusPublished - 1999

Keywords

  • ΔG of ATP hydrolysis
  • Brain
  • Coenzyme Q
  • Intracellular magnesium
  • Mitochondrial cytopathies

ASJC Scopus subject areas

  • Endocrinology
  • Neuroscience(all)
  • Endocrinology, Diabetes and Metabolism

Fingerprint Dive into the research topics of 'Low brain intracellular free magnesium in mitochondrial cytopathies'. Together they form a unique fingerprint.

  • Cite this

    Barbiroli, B., Iotti, S., Cortelli, P., Martinelli, P., Lodi, R., Carelli, V., & Montagna, P. (1999). Low brain intracellular free magnesium in mitochondrial cytopathies. Journal of Cerebral Blood Flow and Metabolism, 19(5), 528-532.