Evaluation of the effects of thymoquinone on red blood cell deformability, morphology, and endothelial nitric oxide synthase (eNOS) synthesis in rat lower extremity ischemia-reperfusion injury.

Background: Erythrocyte deformability refers to the ability of erythrocytes to bend and twist as they pass through capillaries, which is crucial for tissue perfusion. This study aims to investigate the effects of Thymoquinone treatment on erythrocyte deformability in rats subjected to lower extremity ischemia-reperfusion injury.

Methods: The study was conducted on Wistar albino rats weighing 400-450 g. The rats were randomly divided into five groups: the control group (C), in which no treatment was applied; the group that received dimethyl sulfoxide (DMSO) as a solvent; the group subjected to 90 minutes of ischemia followed by 90 minutes of reperfusion in the main femoral artery of the lower extremity (IR); the Thymoquinone control group (TQ-C), in which the effects of Thymoquinone alone were examined; and the group that received intraperitoneal Thymoquinone one hour before the ischemia-reperfusion procedure (IR+TQ). At the end of the procedure, intracardiac blood was collected from the rats, and May-Grunwald and Giemsa (MGG) staining, endothelial nitric oxide synthase (eNOS), and erythrocyte deformability indexes were measured.

Results: The study results showed significant differences. Erythrocyte deformability was statistically significantly improved in the group that received Thymoquinone before ischemia-reperfusion compared to the group subjected to ischemia-reperfusion only. Mor-phological changes in erythrocytes were also statistically significantly better in the IR+TQ group than in the IR group. Immunohisto-chemical eNOS staining revealed that eNOS activity in the IR group was lower than in the IR+TQ group.

Conclusion: Our study demonstrates that Thymoquinone treatment administered before ischemia exerts protective effects against erythrocyte deformation and morphological deterioration by increasing eNOS activity.