Formulation of a topical preparation from Myrtus communis leaf extract and evaluation of its effects on coagulating factors in experimental bleeding model in rats

Abstract

Introduction: Myrtus communis L. (MC) is a well-known medicinal plant in traditional Persian medicine, which contains a large amount of phenolic compounds (mainly hydrolyzable tannins). As mentioned in ancient literature, MC was widely used to control bleeding in every part of the body. Nevertheless, there is no pharmacological study on the anti-hemorrhagic activity of this plant till now. Aim: Formulation of a topical preparation from Myrtus communis leaf extract and evaluation of its hemostatic effects using in vitro and in vivo studies. Materials and Methods: For this porpose, M. communis L. aqueous leaf extract was prepared and the amounts of total phenolic compounds as well as total tannins were determined using starndard methods. The 5% gel of leave extract was formulated by adding appropriate excipients and control tests were performed. Then, two parameters of bleeding time and amount in tail bleeding model were measured in vivo in rats treated with the following: M. communis aqueous leaf extract (MCE) (1%, 2.5%, 5%, 7.5%, 10%, 15%, and 20% w/v), 5% M. communis aqueous leaf extract gel (MCG), tannic acid (TA) (1%, 2.5%, 5%, 7.5%, and 10%), normal saline (NS), and the Monsel’s solution (MS), a commercial hemostatic agent. Also, the effect of 5% MCE and 5% TA on PT (prothrombin time) and aPTT (activated partial thromboplastin time) as well as protein precipitation and platelet aggregation were assessed in vitro. Results: In the rat-tail bleeding model, bleeding time and amount were significantly (P <0.001) reduced by the application of 5% MCE on the cut tail compared with the NS group. The bleeding time and amount in the MS group were not significantly different from those of the 5% MCE group. Platelet microaggregates were detected by fluorescent microscope. PT and aPTT values increased about the two fold of the basic values by the application of 5% MCE. Also, protein precipitation and significant reduction in serum proteins were observed in the 5% MCE group. Conclusion: The current study provided new insights into the hemostatic effect of MCE, which may be partially mediated by platelet aggregation activity. Hence, it could be evaluated as the resource of new plant origin hemostatic agent.