Open Access

ARTICLE

«Silver Bullet of Acidification»: Studying Anti-PD Neuroprotective Mechanisms of Transient pH-Decrease

Kristina A. Kritskaya, Evgeniya I. Fedotova, Alexander D. Nadeev^*, Alexey V. Berezhnov^*

Institute of Cell Biophysics, Russian Academy of Sciences, Federal Research Center “Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences”, Pushchino, 142290, Russia

* Corresponding Authors: Alexander D. Nadeev. Email: ; Alexey V. Berezhnov. Email:

(This article belongs to the Special Issue: Mitochondrial Dysfunction in Metabolic and Neuromuscular Diseases: Mechanisms and Therapeutic Strategies)

BIOCELL 2025, 49(3), 451-464. https://doi.org/10.32604/biocell.2025.061624

Received 28 November 2024; Accepted 27 February 2025; Issue published 31 March 2025

Abstract

Objective: Activation of mitophagy is a promising option to overcome the mitochondrial malfunction that accompanies many diseases. Herein, we investigate the mechanisms underlying the ability of sodium lactate and pyruvate to initiate mitophagy, from the perspective of action on mitochondrial network and expression levels. Methods: Fluorescent and confocal microscopy was used to assess key cell parameters characterizing the state of the mitochondrial network and the level of mitophagy in human fibroblasts carrying mutations in genes encoding LRRK2 and PINK1 after the combined application of lactate and pyruvate and after direct acidification. qRT-PCR was used to study the expression levels of key mitophagy genes. Results: Cells with a mutation in the PINK1 gene showed a lower basal cytosolic pH. The application of sodium lactate and pyruvate to the cells with mutations associated with Parkinson’s disease caused intracellular acidification. Lowering extracellular pH to 6.0 led to a decrease in mitochondrial membrane potential, while the effect of lactate and pyruvate tended to increase this parameter. Extracellular acidification, as well as the effects of lactate and pyruvate, led to an increased level of mitophagy, and also affected such parameters of the mitochondrial network morphology as the ratio of individual to network mitochondria, branch length in mitochondrial network, number of mitochondrial junctions in the network, and also altered the expression of key mitophagy genes. Conclusion: Direct acidification and one induced by lactate and pyruvate do not differ in the efficiency of their effects on the mitochondrial network and mitophagy but change the cell fate differently. The mechanisms of acidification-induced activation of mitophagy differ in control and mutant fibroblasts.

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Supplementary Material

Supplementary Material File

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