PK11195 Inhibits Mitophagy Targeting the F1Fo-ATPsynthase in Bcl-2 Knock-Down Cells

Title:PK11195 Inhibits Mitophagy Targeting the F1Fo-ATPsynthase in Bcl-2 Knock-Down Cells

Volume: 12 Issue: 4

Author(s): M. S.D. Seneviratne, D. Faccenda, V. De Biase and M. Campanella

Affiliation:

Keywords: Bcl-2, F1Fo-ATPsynthase, mitophagy, PK11195

Abstract: The pharmacological agent 1-(2-Chlorophenyl-N-methylpropyl)-3-isoquinolinecarboxamide (PK11195) is the prototypical ligand of the 18-kDa Translocator Protein (TSPO) but at μM concentrations deactivates the oncoprotein Bcl-2 increasing the efficiency of chemotherapeutic agents and promoting the Ca2+-dependent macro-autophagy (or autophagy).

In this paper, we report that PK11195, in HeLa cells, modifies the mitochondria-targeted type of autophagy - hereafter referred to as mitophagy- and the associated resizing of the mitochondrial network but does so exclusively in absence of the oncoprotein Bcl-2 (Bcl-2 Kd cells).

This is consequence of a “side” targeting of the mitochondrial F1Fo-ATPsynthase enzyme, since identical outcome is mimicked by the antibiotic Oligomycin, of which PK11195 matches the effect on: i) mitochondrial membrane potential (ΔΨm), ii) ATP homeostasis and iii) Reactive Oxygen Species (ROS) generation.

Taken together, these data highlight a novel TSPO-independent biological effect for PK11195 and provide evidences for a hitherto uncovered Bcl-2-dependent role of the F1Fo-ATPsynthase in mitochondrial quality control.

Cite this article as:

S.D. Seneviratne M., Faccenda D., De Biase V. and Campanella M., PK11195 Inhibits Mitophagy Targeting the F1Fo-ATPsynthase in Bcl-2 Knock-Down Cells, Current Molecular Medicine 2012; 12 (4) . https://dx.doi.org/10.2174/1566524011207040476