LRRK2 deficiency induced mitochondrial Ca2+ efflux inhibition can be rescued by Na+/Ca2+/Li+ exchanger upregulation

Cell Death Dis. 2019 Mar 19;10(4):265. doi: 10.1038/s41419-019-1469-5.

Abstract

Variants of leucine-rich repeat kinase 2 (lrrk2) are associated with an increased risk in developing Parkinson's disease (PD). Mitochondrial dysfunction and specifically mitochondrial Ca2+ handling has been linked to the pathogenesis of PD. Here we describe for the second time a mitochondrial Ca2+ efflux deficiency in a model displaying alterations in a PD-associated risk protein. LRRK2 deletion, inhibition and mutations led to an impaired mitochondrial Ca2+ extrusion via Na+/Ca2+/Li+ exchanger (NCLX) which in turn lowered mitochondrial permeability transition pore (PTP) opening threshold and increased cell death. The mitochondrial membrane potential was found not to be the underlying cause for the Ca2+ extrusion deficiency. NCLX activity was rescued by a direct (phosphomimetic NCLX mutant) and indirect (protein kinase A) activation which in turn elevated the PTP opening threshold. Therefore, at least two PD-associated risk protein pathways appear to converge on NCLX controlling mitochondrial Ca2+ extrusion and therefore mitochondrial health. Since mitochondrial Ca2+ overload has been described in many neurological disorders this study warrants further studies into NCLX as a potential therapeutic target.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Astrocytes / drug effects
  • Astrocytes / metabolism
  • Biological Transport
  • Calcium / metabolism*
  • Cell Death / drug effects
  • Cell Death / genetics
  • Cell Death / physiology
  • Humans
  • Leucine-Rich Repeat Serine-Threonine Protein Kinase-2 / genetics
  • Leucine-Rich Repeat Serine-Threonine Protein Kinase-2 / metabolism*
  • Lithium / metabolism
  • Membrane Potential, Mitochondrial / drug effects
  • Membrane Potential, Mitochondrial / physiology
  • Mice
  • Mice, Knockout
  • Mitochondria / chemistry
  • Mitochondria / drug effects
  • Mitochondria / genetics
  • Mitochondria / metabolism*
  • Neuroglia
  • Neurons / drug effects
  • Neurons / metabolism
  • Parkinson Disease / genetics
  • Parkinson Disease / metabolism*
  • Rats
  • Rats, Sprague-Dawley
  • Sodium / metabolism
  • Sodium-Calcium Exchanger / genetics
  • Sodium-Calcium Exchanger / metabolism*
  • Up-Regulation

Substances

  • Sodium-Calcium Exchanger
  • Lithium
  • Sodium
  • LRRK2 protein, human
  • Leucine-Rich Repeat Serine-Threonine Protein Kinase-2
  • Lrrk2 protein, mouse
  • Calcium