title: Attenuation of Thrombosis by Crude Rice (Oryza sativa) Bran Policosanol Extract:Ex VivoPlatelet Aggregation and Serum Levels of Arachidonic Acid Metabolites.
abstract: Background. Vascular occlusion or thrombosis was often attributed to uncontrolled platelet activation. Influence of sugarcane policosanol extract on platelet was reported but little was known of rice bran policosanol, particularly its mechanisms of actions on platelet activities.Objective. Antiplatelet mechanisms of rice bran policosanol extract (RBE) were studied using hyperlipidemic Sprague Dawley rats.Ex vivoplatelet aggregation, platelet count (PC), bleeding time (BT), and coagulation time were assayed. Serum eicosanoids and other aggregation-related metabolites levels were quantified.Design. Rats were divided into 6 groups for comparisons (vehicle control Tween 20/H2O, high dose policosanol 500 mg/kg, middle dose policosanol 250 mg/kg, low dose policosanol 100 mg/kg, and positive control aspirin 30 mg/kg).Results. Low dose 100 mg/kg of RBE inhibited aggregation by 42.32 ± 4.31% and this was comparable with the effect of 30 mg/kg aspirin, 43.91 ± 5.27%. Results showed that there were no significant differences in PC, BT, and coagulation time among various groups after RBE treatment. Serum thromboxane A2was attenuated while prostacyclin level increased upon RBE treatment.Conclusions. RBE reducedex vivoADP-induced platelet aggregation without giving adverse effects. No changes in full blood count suggested that rice bran policosanol did not disturb biological blood cell production and destruction yet it reduced aggregation through different mechanisms.
authors: Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors: Wai-Teng
authors: 0000-0001-9334-9372
authors: WT
authors: Wong
authors: Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Department of Nutrition and Dietetics, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors: Maznah
authors: M
authors: Ismail
authors: Department of Pathology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors: Eusni Rahayu Mohd
authors: ER
authors: Tohit
authors: Department of Veterinary Laboratory Diagnostics, Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
authors: Rasedee
authors: R
authors: Abdullah
authors: Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia; Cardiology Department, Affiliated Hospital of Chengde Medical University, Chengde, Hebei 067000, China.
authors: Yi-Da
authors: YD
authors: Zhang