Dynamics of mitochondrial membranes under photo-oxidative stress with high spatiotemporal resolution

Vincent Loriette; Alexandra Fragola; Sergei G Kruglik; Susmita Sridhar; Antoine Hubert; François Orieux; Eduardo Sepulveda; Franck Sureau; Stephanie Bonneau

doi:10.3389/fcell.2023.1307502

Dynamics of mitochondrial membranes under photo-oxidative stress with high spatiotemporal resolution

Front Cell Dev Biol. 2023 Nov 17:11:1307502. doi: 10.3389/fcell.2023.1307502. eCollection 2023.

Authors

Affiliations

¹ ESPCI, PSL Research University, Sorbonne Université, CNRS, Laboratoire de Physique et D'Étude des Matériaux (LPEM), Paris, France.
² Sorbonne Université, CNRS, Laboratoire Jean Perrin (LJP), Paris, France.
³ Centrale Supelec, Université Paris Saclay, CNRS, Laboratoire des Signaux et Systémes (L2S), Gif-sur-Yvette, France.
⁴ Sorbonne Université, Université Paris Cité, CNRS, Laboratoire de physique nucléaire et de hautes énergies (LPNHE), Paris, France.

Abstract

In our study, we harnessed an original Enhanced Speed Structured Illumination Microscopy (Fast-SIM) imaging setup to explore the dynamics of mitochondrial and inner membrane ultrastructure under specific photo-oxidation stress induced by Chlorin-e6 and light irradiation. Notably, our Fast-SIM system allowed us to observe and quantify a distinct remodeling and shortening of the mitochondrial structure after 60-80 s of irradiation. These changes were accompanied by fusion events of adjacent inner membrane cristae and global swelling of the organelle. Preceding these alterations, a larger sequence was characterized by heightened dynamics within the mitochondrial network, featuring events such as mitochondrial fission, rapid formation of tubular prolongations, and fluctuations in cristae structure. Our findings provide compelling evidence that, among enhanced-resolution microscopy techniques, Fast-SIM emerges as the most suitable approach for non-invasive dynamic studies of mitochondrial structure in living cells. For the first time, this approach allows quantitative and qualitative characterization of successive steps in the photo-induced oxidation process with sufficient spatial and temporal resolution.

Keywords: Chlorin-e6; dynamics; live cell imaging; mitochondria; oxidation; shape changes; structured illumination microscopy (SIM); sub-organelles structures.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was funded by a Sorbonne Université Emergence Grant and Fellowship.