Scientific Rationale for the Use of Peganum Harmala in Cardiovascular Diseases

Abstract

The indigenous herb, Peganum harmala has been used to treat a myriad of cardiovascular diseases in traditional medicine in many countries such as Pakistan and Iran. Yet, the pharmacological rationale for the use of this herb has not been established.  In an attempt to discern the scientific bases of the use of this herb, a crude extract and three polarity fractions were made and the effects were checked on the arachidonic acid (AA) metabolism. PH fractions successfully inhibited cyclooxygenase (COX) and lipoxygenase (LOX) mediated metabolites of AA. These metabolites include stable thromboxane (TX) A₂ analog called TXB₂, 12-hydroxyeicosatetraenoic acid (HETE), and lipoxygenase product (LP)-1. Antiplatelet activity of PH was observed against AA-induced platelet aggregation which may be due to the blockade of TXB_2. A dose-dependent antiplatelet activity by PH was seen against platelet-activating factor (PAF) and Adenosine diphosphate (ADP), but not with the collagen.  Glutathione peroxidase (GPx) activity was also increased by PH. A specific pattern in the pharmacological actions of the PH metabolites was noted as well. Our results, henceforth, suggest that the underlying mechanism of the cardioprotective function of PH may be the inhibition of AA-induced platelet aggregation.