Non-clinical investigations about cytotoxic and anti-platelet activities of gamma-terpinene

Abstract

Gamma-terpinene (γ-TPN) is a cyclohexane monoterpene, isolated from essential oils of pharmacologically active plant species, such as tea tree (Melaleuca alternifolia), oregano (Origanum vulgare), rosemary (Rosmarinus o cinalis L.), thyme (Thymus vulgaris Marchand) and eucalyptus (Eucalyptus sp.). Terpenes are widely studied for their recognized pharmacological actions on the cardiovascular system, hemostasis and antioxidant actions. The objective of this study was to investigate the cytotoxic and antiplatelet activity of γ-TPN in non-clinical study models. For the in silico evaluation, the PreADMET, SwissADME and SwissTargetPrediction software were used. Molecular docking was performed using the AutoDockVina and BIOVIA Discovery Studio databases. The cytotoxicity of γ-TPN was analyzed by the MTT assay with normal murine endothelial (SVEC4-10) and broblast (L929) lines. Platelet aggregation was evaluated with platelet-rich (PRP) and platelet-poor (PPP) plasma from spontaneously hypertensive rats (SHR), in addition to SVEC4-10 cells pre-incubated with γ-TPN (50, 100 and 200 µM) for 24 h. In in vivo tests, SHR animals were also used, pre-treated by gavage with γ-TPN for 7 days, distributed into four groups (control, 25, 50 and 100 mg/Kg). At the end, blood samples were collected to measure nitrites using the Griess reagent. γ-TPN proved to be quite lipid-soluble (Log P = + 4.50), with a quali ed pro le of similarity to the drug, good bioavailability, and adequate pharmacokinetics. The monoterpene exhibited a nity mainly for the P2Y12 receptor (6.450 ± 0.232 Kcal/mol), moderate cytotoxicity for L929 (CC 50 = 333.3 µM) and SVEC 4-10 (CC 50 = 366.7 µM). The presence of γ-TPN in SVEC 4-10 cells was also able to reduce platelet aggregation by 51.57 and 44.20%, respectively, at the lowest concentrations (50 and 100 µM). It was concluded that γ-TPN has a good a nity with purinergic receptors and an effect on the reversal of platelet aggregation and oxidative stress, being promising and safe for therapeutic targets and subsequent studies in the control of thromboembolic diseases.