Mitochondria’s Morphology Seen in All Its Variety

A team of researchers have designed a new method to determine, in a rapid and apparently accurate way, the morphology of mitochondria in cells using a microscope. Through this method, called Flicker-assisted Localization Microscopy (FaLM), researchers discovered that in vivo models of hypertension are characterized by larger mitochondria, occupying more of the cell volume and being more densely clustered. The study, titled “Flicker-assisted localization microscopy reveals altered mitochondrial architecture in hypertension,” was published in the journal Scientific Reports.

Mitochondria, double membrane-bound organelles found in most eukaryotic cells, are considered the cells’ powerhouses, the key organelles responsible for generating the energy cells need to function properly. Mitochondria also have an impact on other aspects of cell and organism physiology: they contribute to proliferation, migration and contraction, and they modulate phenotypes and cell death by regulating signaling and energy requirements. These functions are interconnected with mitochondria morphology, and can range from small spheres, swollen spheres, straight rods, twisted rods, branched rods and loops, to branched networks and single continuous mitochondrial reticula. Mitochondria morphology impacts both normal physiology and disease development.

A team of researchers at the Strathclyde Institute of Pharmacy & Biomedical Sciences, in Glasgow, U.K., together with colleagues at the Department of Physics, Durham University, in Durham, U.K., determined mitochondria morphology by measuring the shape of electrically discrete mitochondria and imaging the organelles individually, a new method that allows researchers to know mitochondria functional boundaries. The FaLM method rapidly defined the size, shape, position, and density of all mitochondria within a cell.

The FaLM technique showed that mitochondria are larger in a rat model of hypertension. Moreover, they observed that mitochondria in freshly isolated ex vivo resistance artery smooth muscle, taken from hypertensive animals, were clustered together more tightly when compared to controls.

The team highlights that the findings support FaLM as a new, rapid, accurate and convenient method of assessing and comparing mitochondria, observations that could aid the understanding of how alterations to mitochondrial structure contributes to disease — in this case to the alteration of vessel architecture in hypertension.