Mitochondrial Antioxidant SkQ1 Improves Hypothermic Preservation of the Cornea

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Galina S. Baturina^1,2, Lubov E. Katkova¹, Irina G. Palchikova^2,3, Nataliya G. Kolosova¹, Evgeniy I. Solenov^1,2,4,a*, and Igor A. Iskakov⁵

¹Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia

²Novosibirsk State University, 630090 Novosibirsk, Russia

³Technological Design Institute of Scientific Instrument Engineering, Siberian Branch of the Russian Academy of Sciences, 630058 Novosibirsk, Russia

⁴Novosibirsk State Technical University, 630087 Novosibirsk, Russia

⁵Fyodorov Eye Microsurgery Complex, 630096 Novosibirsk, Russia

^* To whom correspondence should be addressed.

Received July 28, 2020; Revised October 16, 2020; Accepted October 16, 2020

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Diseases of the cornea are a frequent cause of blindness worldwide. Keratoplasty is an efficient method for treating severely damaged cornea. The functional competence of corneal endothelial cells is crucial for successful grafting, which requires improving the media for the hypothermic cornea preservation, as well as developing the methods for the evaluation of the corneal functional properties. The transport of water and ions by the corneal endothelium is important for the viability and optic properties of the cornea. We studied the impact of SkQ1 on the equilibrium sodium concentration in the endothelial cells after hypothermic preservation of pig cornea at 4°C for 1, 5, and 10 days in standard Eusol-C solution. The intracellular sodium concentration in the endothelial cells was assayed using the fluorescent dye Sodium Green; the images were analyzed with the custom-designed CytoDynamics computer program. The concentrations of sodium in the pig corneal endothelium significantly increased after 10 days of hypothermic preservation, while addition of 1.0 nM SkQ1 to the preservation medium decreased the equilibrium concentration of intracellular sodium (at 37°C). After 10 days of hypothermic preservation, the permeability of the plasma membrane for sodium decreased in the control cells, but not in the cells preserved in the presence of 1 nM SkQ1. Therefore, SkQ1 increased the ability of endothelial cells to restore the intracellular sodium concentration, which makes SkQ1 a promising agent for facilitating retention of the functional competence of endothelial cells during cold preservation.

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KEY WORDS: corneal endothelium, hypothermic preservation, SkQ1, intracellular sodium

DOI: 10.1134/S0006297921030135

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