Research Paper|Volume 13, Issue 22|pp 24524—24541

Progressive reorganization of mitochondrial apparatus in aging skeletal muscle of naked mole rats (Heterocephalus glaber) as revealed by electron microscopy: potential role in continual maintenance of muscle activity

Valeriya Vays¹, Irina Vangely¹, Chupalav Eldarov¹, Susanne Holtze², Thomas Hildebrandt², Lora Bakeeva¹, Vladimir Skulachev¹

¹Lomonosov Moscow State University, Belozersky Research Institute of Physico-Chemical Biology, Moscow 119991, Russia
²Department of Reproduction Management, Leibniz-Institute for Zoo and Wildlife Research, Berlin 10315, Germany

Received: May 25, 2021Accepted: July 1, 2021Published: November 28, 2021

https://doi.org/10.18632/aging.203720

Copyright: © 2021 Vays et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

The authors examined the ultrastructure of mitochondrial apparatus of skeletal muscles of naked mole rats (Heterocephalus glaber) from the age of 6 months to 11 years. The obtained results have demonstrated that the mitochondria in skeletal muscles of naked mole rats aged below 5 years is not well-developed and represented by few separate small mitochondria. Mitochondrial reticulum is absent. Starting from the age of 5 years, a powerful mitochondrial structure is developed. By the age of 11 years, it become obvious that the mitochondrial apparatus formed differs from that in the skeletal muscle of adult rats and mice, but resembles that of cardiomyocytes of rats or naked mole rats cardiomyocytes. From the age of 6 months to 11 years, percentage area of mitochondria in the skeletal muscle of naked mole rat is increasing by five times. The growth of mitochondria is mainly driven by increased number of organelles. Such significant growth of mitochondria is not associated with any abnormal changes in mitochondrial ultrastructure.

We suppose that specific structure of mitochondrial apparatus developed in the skeletal muscle of naked mole rats by the age of 11 years is necessary for continual skeletal muscle activity of these small mammals burrowing very long holes in stony earth, resembling continual activity of heart muscle. In any case, ontogenesis of naked mole rat skeletal muscles is much slower than of rats and mice (one more example of neoteny).