Effect of the Peptide Calcium Channel Blocker ω-hexatoxin-Hv1a on Cell Death during Ischemia/Reperfusion in vitro

Apoptosis and necrosis during reperfusion after ischemia are key mechanisms at the cellular level leading to damage. The development of pathological conditions is preceded by intracellular calcium ion overload both at the stage of ischemia and at the stage of reperfusion. In this regard, one of the strategies aimed at reducing damage during ischemia/reperfusion is associated with the use of calcium channel blockers. The aim of the study was to study the effect of a peptide toxin, a calcium channel blocker ω-hexatoxin-Hv1a, on different types of epithelial cell death during in vitro reconstruction of ischemia/reperfusion conditions characteristic of organ transplantation.

In this study, we used CHO-K1 epithelial cell culture. Changes in apoptosis, necrosis, cell index, and calcium ion concentration were assessed when modeling ischemia/reperfusion processes in vitro with the addition of a calcium channel blocker toxin. Ischemic and reperfusion injury was achieved by oxygen and nutrient deprivation followed by reperfusion in a complete nutrient medium. The measurements were performed using a multimodal plate reader-fluorimeter.

An increase in apoptosis, necrosis, and the concentration of calcium ions was recorded when modeling ischemia/reperfusion processes. A decrease in the level of apoptosis and necrosis, as well as the concentration of calcium ions to a physiological level or a level close to physiological, was noted when the toxin was added at a concentration of 50 nM at the reperfusion stage. The cell index showed a faster restoration in the presence of the toxin.

The experimental data confirm the hypothesis of a beneficial effect of peptide calcium channel blockers on the state of epithelial cells during reperfusion after ischemia and can be considered for further study as a strategy for organ adaptation before reperfusion.