RESUMEN
Thrombosis is the formation of a clot within a blood vessel. Antithrombotic drugs are used for treating thrombosis, which can be the cause of hemorrhage. Currently, there is a need to discover novel antithrombotic drugs. Walnut is widely used to treat a wide range of health complaints. In this study, walnut bark extract was tested in hemostasis parameters: platelets adhesion, aggregation, and plasmatic coagulation in human blood. The crude aqueous extract of walnut bark was prepared by infusion and tested in vitro on hemostasis. Through blood collection from healthy volunteer donors, we studied different parameters of the primary hemostasis: platelet adhesion on the collagen-coated surface under flow, ADP, collagen, thrombin, and arachidonic acid-induced platelet aggregation, and of the secondary hemostasis by measuring prothrombin time (PT) and activated partial thromboplastin (APTT) parameters. All experiments are realized in the absence and presence of the extract and repeated at least twice. The obtained data showed that the extract (1 and 2 mg/mL) significantly (p < 0.001) reduced the activated platelet adhesion on the collagen-coated surface. In the same way, the effect of the extract on platelet aggregation seems to depend on its concentration and on the nature of the agonist. The strongest inhibition of aggregation was observed in the case of collagen at 1 mg/mL, while there was no observed effect on arachidonic acid-induced aggregation. Moreover, the extract (1 mg/mL) affects the extrinsic, intrinsic, and common pathways of the human blood coagulation cascade by extending significantly (p < 0.001), both PT and APTT times. This study provides evidence that walnut bark extract, by its antiadhesive, antiaggregant, and anticoagulant activities, could be considered as a serious source of biological compounds for the prevention and treatment of thrombosis.
RESUMEN
MATERIALS AND METHODS: Acute toxicity test was performed on Swiss albino mice at a single oral dose of 1-10 g/kg for 14 consecutive days. General behavioral adverse effects, mortality, and latency of mortality were determined. In the subacute study, the Haloxylon scoparium Pomel extract was administered orally at doses of 500, 1000, and 2000 mg/kg daily for 30 days to Wistar rats. Body weight and selected biochemical and hematological parameters were determined at the end of the experiment. Sections of livers and kidneys were removed for histological studies. RESULTS: Acute toxicity study showed that the oral LD50 value of Haloxylon scoparium Pomel extract was 5000 mg/kg. The subacute toxicity study of Haloxylon scoparium Pomel extract at doses 500, 1000, and 2000 mg/kg did not produce any observable symptoms of toxicity and no significant variation in body weight, organ weights, food, and water consumption or mortality in all treated rats. However, the administration of the Haloxylon scoparium Pomel extract to rats at 500 mg/kg and 1000 mg/kg showed a significant decrease in platelets. Moreover, only at the highest dose (2000 mg/kg), the extract caused a significant increase in red blood cells and hemoglobin. Our results showed that subacute treatments with Haloxylon scoparium Pomel extract at doses of 1000 mg/kg and 2000 mg/kg significantly elevated alkaline phosphatase and triglycerides. Histological studies showed that the subacute treatments of rats with Haloxylon scoparium Pomel extracts, at the doses 1000 and 2000 mg/kg, induced some histopathological changes in the livers but a slight changing in kidneys. CONCLUSION: Our results indicated low acute toxicity of the aqueous extract of Haloxylon scoparium Pomel. Furthermore, daily oral administration of Haloxylon scoparium Pomel extract caused some damages to the livers of rats treated with high doses, expressed by an increase in some enzyme activities such as ALP. Regarding the renal function, we did not find remarkable toxicity in the subacute treatment with Haloxylon scoparium Pomel extracts at doses 1000 and 2000 mg/kg. However, further toxicity assessments should be done to ascertain the safety or the toxicity of this valuable plant species "Haloxylon scoparium pomel" in subchronic treatments.
