Investigation of Uterotonic Activities, Acute Toxicity in Rats and Phytochemical Composition of Hydnora Abyssinica and Uvariodendron Anisatum Extracts

Abstract

Uterotonic drugs are used to manage postpartum bleeding in the mainstream medical systems. However, global maternal mortalities due to postpartum complications are still high due to lack of timely interventions, qualified staff, and total costs of hospital-based deliveries. Traditional medicine systems provide primary health care alternatives for the management of postpartum hemorrhage. Over 80% of cultural societies in low-income Countries use plant preparations in traditional medicine with unknown potency and safety profiles. In light of this background, the current study investigated uterotonic activities, toxicity in rats, and phytochemical composition of Hydnora abyssinica and Uvariodendron anisatum extracts. The plants were collected from Embu County, where they are used in removing retained placenta and management of postpartum hemorrhage. Laboratory experimental design was adopted and the extracts were macerated and extracted using ethanol and water. Uterus for uterotonic activity assay was isolated from primed mature female Wistar rats. A piece of the uterus (2 cm) was mounted on an organ bath and exposed to De Jalon’s solution as a negative control and oxytocin (positive control), and extracts with concentrations varying from 0.5 to 4.0 mg/ml were added. Acute oral toxicity studies were done following the OECD 423 guideline and phytochemical screening by adopting the standard phytochemical procedure. The study was approved by the Faculty of Veterinary Medicine Biosafety, Animal Use, and Ethics Committee of the University of Nairobi, and the National Commission for Science, Technology, Innovation. Data obtained from the uterotonic activities was analysed using GraphPad Prism Version 8.0.1 software and was expressed as a percentage increase or decrease in the mean ± standard error of the mean (SEM) relative to the controls. The findings of acute oral toxicity of H. abyssinica rhizome and U. anisatum root extracts were expressed using a dose that causes a mortality of 50% of study animals (LD50). Additionally, the phytochemical components of the plants in this study were tabulated. It was found that the xv extracts of H. abyssinica rhizome and U.anisatum root had uterotonic activity. The ethanol extracts of H. abyssinica rhizome demonstrated significantly high activity compared with that of the water extract at p < 0.001***. On the other hand, the uterotonic effect of U. anisatum root water extracts was higher than that of ethanol. A single dose of the H abyssinica rhizome and U. anisatum root at 2000 mg/kg did not cause mortality of the tested Wistar rats. Alkaloids, glycosides, phytosterols, triterpenes, diterpenes, proteins, phenols, flavonoids and fixed were present in H. abyssinica and U. anisatum. However, saponins and volatile oils were only present in U. anisatum. The findings from this study provide scientific evidence which is useful in validating the use of H. abyssinica and U. anisatum extracts in the removal of retained placenta.