Comparative multitarget vaso-protective effects of brown and black Vigna unguiculata (L.) walp extracts: Evidence of stronger modulation of sickle cell pathophysiology by the brown variety.

ETHNOPHARMACOLOGICAL RELEVANCE: Vaso-occlusive crisis (VOC) in sickle cell disease (SCD) arises from hemoglobin S (HbS) polymerization, endothelial activation, inflammation, hemolysis, and coagulation imbalance. Plant-derived agents with multitarget activity may provide new mechanistic interventions.

AIM OF THE STUDY: This study comparatively evaluated the in vitro vaso-protective effects of ethanolic extracts of the brown and black varieties of Vigna unguiculata and explored mechanisms relevant to SCD pathophysiology.

MATERIALS AND

METHODS

Standard in vitro assays assessed HbS polymerization, sickling reversibility, adhesion molecule expression, inflammatory cytokines, coagulation indices, and hemolysis markers. Phytochemical screening, GC-MS profiling, and molecular docking were performed to characterize constituents and predict ligand-protein interactions.

RESULTS

Both extracts significantly (p < 0.05) inhibited HbS polymerization, reduced sickled erythrocytes, and downregulated adhesion molecules (P-selectin, E-selectin, VCAM-1, ICAM-1), inflammatory cytokines (IL-6, TNF-α, IL-1β, CRP), and coagulation markers (D-dimer, PF1+2, TAT complexes, fibrinogen). They also enhanced nitric oxide bioavailability and reduced plasma free hemoglobin, bilirubin, platelets, and Annexin V+ RBCs, indicating protection against hemolysis. The brown variety consistently showed greater efficacy than the black variety and hydroxyurea across several in vitro endpoints. Phytochemical analysis revealed abundant flavonoids, alkaloids, phenolics, terpenoids, saponins, and glycosides. Gas chromatography-mass spectrometry (GC-MS) identified bioactive compounds, with several showing strong predicted interactions with HbS and endothelial adhesion targets.

CONCLUSION

The brown variety of V. unguiculata demonstrates promising multitarget in vitro activity modulating pathways central to VOC. These findings support further investigation, although in vivo and clinical validation are required before therapeutic applications can be inferred.