Acute and Subacute Toxicity Studies of the Ethyl Acetate Soluble Proanthocyanidins of the Immature Inflorescence of Cocos nucifera L. in Female Wistar Rats

Abstract

Ayurvedic and traditional medical practitioners of Sri Lanka use the decoction of the immature inflorescence of Cocos nucifera L. (IC) variety aurantiaca for the treatment of menorrhagia. The progestogenic effect of the ethyl acetate soluble proanthocyanidins (EASPA) of the IC in female rats at a dose of 3.5 mg/kg body weight has been reported. Acute and subacute toxicity studies of EASPA of the IC carried out using female Wistar rats according to Organization for Economic Co-operation and Development (OECD) guidelines 423 and 407, respectively, are reported herein. In the acute toxicity study, a single dose of EASPA (2000 mg/kg body weight) was orally administered to rats, which were monitored for 14 days. In the subacute toxicity study, rats were orally administered with EASPA daily for 28 days at doses of 1.75, 3.5, 7, and 14 mg/kg body weight. No rat in either the acute or subacute toxicity study exhibited mortality or clinical signs of toxicity. Further, these rats did not show any significant change in their mean body weight, food, and water intake, haematological and biochemical parameters as well as in the results of their histopathological examinations compared to those of control group rats. According to results of the acute toxicity, the LD50 of EASPA is estimated to be greater than 2000 mg/kg body weight. Considering the results of the subacute toxicity study, the oral administration of EASPA daily for 28 days was well tolerated up to the dose, 14 mg/kg by rats. These results will be useful in the development of a novel therapeutic agent from EASPA of the IC for the treatment of menorrhagia, which incapacitates a considerable proportion of women worldwide.