Mitochondria activity evaluation under osmotic conditions

abstract

English

Mitochondria generate large quantities of energy in the form of adenosine triphosphate (ATP), store calcium for cell signaling activities and play an important role in the maintenance of ionic balance. Mitochondria, however, are highly sensitive to any kind of stress in which they mainly respond by disturbance of respiration, and reactive oxygen species (ROS) production. Osmotic stress, in particular, generates ROS that degrades lipids, proteins, and DNA [1]. High accumulation of ROS also can disturb cellular redox homeostasis, and result in ion toxicity and oxidative damage. To respond to such conditions, the mitochondria may change shape and size. They also have been shown to join together in response to stress, which is known as mitochondria fusion. [2] This study aims to investigate the possible effects of KCl and NaCl on Bone marrow-derived (MSCs) mitochondria membrane potential (MMP), morphology and superoxide production. The cells were then stained with JC-10 dye (AAT Bioquest, Inc) for investigating the MMP and MitoLite Red FX600 (AAT Bioquest, Inc) for determining the cell’s mitochondrial morphology. To determine the production of superoxide by mitochondria, MitoSOX (Red mitochondrial superoxide indicator, Invitrogen) was used. The morphology of the stained cells was studied using confocal fluorescent microscopy. The confocal microscope images indicated that both NaCl and KCl strongly decreased mitochondrial membrane potential after 3 and 24 hours (Fig 1). In addition, the mitochondria morphology analysis confirmed that in some cases, the mitochondria normal structure (tubular shape) changed to round shapes under the stress condition (Fig 2). The result of superoxide staining confirmed that the addition of NaCl and KCl in media induced mitochondrial superoxide production of MSCs after 24 h of culture (Fig 3). Overall these results suggested that putting mitochondria under environmental stress conditions may lead to a decrease in MMP, change in mitochondria structure, fusion into large networks to cope with the stressful situation, and higher production of superoxide which can result in oxidative damage.

Mitochondria membrane potential, Mitochondria morphology, Stress, Fusion

EZATI, M.; HASHEMI, A.; ZUMBERG, I.; ČMIEL, V.

4. 9. 2022

Czechoslovak Microscopy Society

Brno

978-80-11-02253-2

16th Multinational Congress on Microscopy 16MCM: BOOK OF ABSTRACTS

244

245

2

https://www.16mcm.cz/wp-content/uploads/2022/09/16MCM-abstract-book.pdf