A Selective and Cell-Permeable Mitochondrial Calcium Uniporter (MCU) Inhibitor Preserves Mitochondrial Bioenergetics After Hypoxia/Reoxygenation Injury

Overview

Journal ACS Cent Sci

Specialty Chemistry

Date 2019 Jan 30

PMID 30693334

Citations 71

Authors

Joshua J Woods

Neeharika Nemani

Santhanam Shanmughapriya

Akshay Kumar

Mengqi Zhang

Sarah R Nathan

Manfred Thomas

Edmund Carvalho

Karthik Ramachandran

Subramanya Srikantan

Peter B Stathopulos

Justin J Wilson

Muniswamy Madesh

Affiliations

Soon will be listed here.

Abstract

Mitochondrial Ca (Ca) uptake mediated by the mitochondrial calcium uniporter (MCU) plays a critical role in signal transduction, bioenergetics, and cell death, and its dysregulation is linked to several human diseases. In this study, we report a new ruthenium complex Ru265 that is cell-permeable, minimally toxic, and highly potent with respect to MCU inhibition. Cells treated with Ru265 show inhibited MCU activity without any effect on cytosolic Ca dynamics and mitochondrial membrane potential (ΔΨ). Dose-dependent studies reveal that Ru265 is more potent than the currently employed MCU inhibitor Ru360. Site-directed mutagenesis of Cys97 in the N-terminal domain of human MCU ablates the inhibitory activity of Ru265, suggesting that this matrix-residing domain is its target site. Additionally, Ru265 prevented hypoxia/reoxygenation injury and subsequent mitochondrial dysfunction, demonstrating that this new inhibitor is a valuable tool for studying the functional role of the MCU in intact biological models.

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