In vitro Anti-sickling Activity of Red Grape Juice (Vitis vinifera L. var. Crimson Seedless) on Human HbSS Erythrocytes

Introduction: Sickle cell disease is characterized by sickle hemoglobin (HbS) polymerization under deoxygenation conditions, causing erythrocyte sickling, hemolysis, and vaso-occlusive complications. Red grape polyphenols exhibit antioxidant properties that may contribute to erythrocyte protection. This study aimed to evaluate the in vitro anti-sickling activity of red grape juice (Vitis vinifera L. var. Crimson Seedless) on HbSS erythrocytes. Methods: An experimental in vitro study was conducted using blood samples from SS phenotype donors. Sickling was induced with 2% sodium metabisulfite according to the Emmel test. Erythrocytes were treated with three grape juice dilutions (1/10, 1/100, and 1/1000). Sickled erythrocytes were quantified by light microscopy, and sickling inhibition was calculated relative to the control. Results were obtained from six independent biological experiments. Results: Red grape juice reduced erythrocyte sickling in a concentration-dependent manner. The highest inhibitory activity was observed at the 1/10 dilution, with 58.52% inhibition, while the 1/100 and 1/1000 dilutions showed lower inhibition rates of 16.03% and 8.24%, respectively. Microscopic analysis showed better preservation of erythrocyte morphology at the 1/10 dilution. Conclusion: Red grape juice (Vitis vinifera L. var. Crimson Seedless) exhibits in vitro anti-sickling activity on HbSS erythrocytes. These findings suggest a potential interest in grape-derived bioactive compounds as complementary candidates for sickle cell disease research. Further studies are needed to identify active compounds, assess safety, and confirm efficacy in preclinical and clinical models.