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bioRxiv · 10.64898/2026.04.02.716077

Red/near-infrared light activates the mitochondrial large-conductance calcium-activated potassium channel in glioblastoma cells.

Bednarczyk, P.·Lewandowska, J.·Kulawiak, B.·Szewczyk, A.
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Abstract

Mitochondrial potassium channels, located in the inner mitochondrial membrane, play a crucial role in the cells life/death phenomenon. Activation of mitochondrial potassium channels by potassium channel openers may protect cells against ischemia-reperfusion injury. It is known that mitochondrial large conductance calcium-activated potassium channels interact with various mitochondrial proteins, including enzymes of the respiratory chain. Numerous studies indicate that the mitochondria, especially cytochrome c oxidase, play a crucial role as a chromatophore in the cellular response to red and near-infrared light. In this study, we employ the patch-clamp technique and single-channel recordings to investigate the regulation of glioblastoma mitochondrial large conductance calcium-activated potassium channel activity by infrared light. Specifically, we examined the effects of wavelengths 620 nm, 680 nm, 760 nm, and 820 nm in a redox-controlled environment. Our findings suggest that illuminating the inner mitochondrial membrane with these wavelengths may activate mitochondrial large conductance calcium-activated potassium channels. These results offer new insights into the regulation of mitochondrial potassium channels by cytochrome c oxidase, which may lead to the development of non-pharmacological interventions with potential cytoprotective benefits.

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Bednarczyk, P., Lewandowska, J., Kulawiak, B., Szewczyk, A.. 2026-04-05. Red/near-infrared light activates the mitochondrial large-conductance calcium-activated potassium channel in glioblastoma cells.. https://doi.org/10.64898/2026.04.02.716077

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