Quercetin protects cardiomyoblasts against hypertonic cytotoxicity by abolishing intracellular Ca2+ elevations and mitochondrial depolarisation

• Published in: Biochemical pharmacology 2024-04, Vol.222, p.116094, Article 116094
• Main Authors: Dostál, Z., Zholobenko, A.V., Přichystalová, H., Gottschalk, B., Valentová, K., Malli, R., Modrianský, M.
• Format: Article
• Language: English
• Subjects: 2,3-dehydrosilybin; Calcium; H9c2 cells; Hypertonic stress; Quercetin
• ISSN: 0006-2952; 1873-2968; 1873-2968
• DOI: 10.1016/j.bcp.2024.116094

[Display omitted] Osmotic changes represent a burden for the body and their limitation would be beneficial. We hypothesized that ubiquitous natural compounds could guard against cytotoxic effects of osmotic stress. We evaluated the anti-hypertonic mechanism of quercetin and 2,3-dehydrosilybin in H9c2 cells in vitro. Protective effect of both compounds was determined by neutral red assay, cell apoptosis was estimated by measuring caspase-3 activity and verified by western blot and annexin V assay. Phosphorylation level of selected proteins was also detected. Mitochondrial membrane potential was evaluated using dye JC-1. Ca2+ signals were evaluated using genetically encoded fluorescent Ca2+ biosensor GCaMP7f. Formation of reactive oxygen species was measured using an oxidant-sensing probe dihydrofluorescein diacetate. Quercetin protected H9c2 cells against hypertonic stress-induced cell death. We observed a significant increase in intracellular Ca2+ levels ([Ca2+]cyto) when cells originally placed in a hypertonic solution were returned to a normotonic environment. Quercetin was found to prevent this increase in [Ca2+]cyto and also the depolarization of mitochondrial membrane potential. Quercetin, but not 2,3-dehydrosilybin, reduced adverse effects of osmotic stress mainly by dampening the elevation of [Ca2+]cyto and mitochondrial Ca2+ overload. This may consequently prevent MPTP pore opening and activation of apoptosis.