Frontiers in Molecular Biosciences (Dec 2023)

Neither too much nor too little: mitochondrial calcium concentration as a balance between physiological and pathological conditions

  • Donato D’Angelo,
  • Denis Vecellio Reane,
  • Denis Vecellio Reane,
  • Anna Raffaello

DOI
https://doi.org/10.3389/fmolb.2023.1336416
Journal volume & issue
Vol. 10

Abstract

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Ca2+ ions serve as pleiotropic second messengers in the cell, regulating several cellular processes. Mitochondria play a fundamental role in Ca2+ homeostasis since mitochondrial Ca2+ (mitCa2+) is a key regulator of oxidative metabolism and cell death. MitCa2+ uptake is mediated by the mitochondrial Ca2+ uniporter complex (MCUc) localized in the inner mitochondrial membrane (IMM). MitCa2+ uptake stimulates the activity of three key enzymes of the Krebs cycle, thereby modulating ATP production and promoting oxidative metabolism. As Paracelsus stated, “Dosis sola facit venenum,”in pathological conditions, mitCa2+ overload triggers the opening of the mitochondrial permeability transition pore (mPTP), enabling the release of apoptotic factors and ultimately leading to cell death. Excessive mitCa2+ accumulation is also associated with a pathological increase of reactive oxygen species (ROS). In this article, we review the precise regulation and the effectors of mitCa2+ in physiopathological processes.

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