Efeitos in vitro de um extrato das folhas de Siparuna guianensis sobre a formação de vasos, agregação plaquetária e coagulação sanguínea

Abstract

Siparuna guianensis is a species widely used in traditional medicine across different regions of Brazil. In this context, plant-derived phenolic metabolites have been extensively investigated for their ability to modulate processes such as platelet function and oxidative stress. Platelet activation mediated by the purinergic P2Y₁₂ receptor plays a central role in amplifying ADP induced aggregation, making it a well-established target in antithrombotic therapy. In this regard, the present study evaluated the antioxidant and antiplatelet potential of an aqueous extract of S. guianensis, combined with phytochemical characterization, toxicological assessment, and in silico analysis of its interaction with the P2Y₁₂ receptor. LC–MS analysis identified quercetin-3,7-di-O-rhamnoside as the major compound in the extract. The total phenolic and flavonoid contents were 9.3 ± 1.2% and 1.21 ± 0.03%, respectively. Antioxidant activity was confirmed using DPPH and ABTS assays, as well as a cellular model employing DCFH-DA. In the DPPH assay, the extract exhibited an IC₅₀ of 3.30 ± 0.16 µg/mL, whereas in the ABTS assay, the IC₅₀ was 572.32 ± 31.19 µg/mL. In the AAPH-induced cellular oxidative stress model, the extract reduced intracellular reactive oxygen species production, with an IC₅₀ of 8.450 ± 1.584 µg/mL. Regarding antiplatelet activity, the extract inhibited ADP-induced platelet aggregation in a concentration-dependent manner, with an IC₅₀ of 359.3 ± 15.3 µg/mL. Molecular docking studies demonstrated a relevant binding affinity of quercetin-3,7-di-O rhamnoside to the P2Y₁₂ receptor (−7.296 ± 0.095 kcal/mol), supporting the plausibility of the proposed mechanism of action. Additionally, hemolysis, platelet viability, and macrophage cytotoxicity assays indicated a favorable safety profile for the extract. Altogether, these findings demonstrate that S. guianensis exhibits antioxidant properties and modulates platelet aggregation via the ADP-dependent pathway, highlighting its potential as a source of bioactive metabolites for applications in the regulation of primary hemostasis.