Effect of ethanolic leaf extract of Macaranga spinosa Muell-Arg on selected biomarkers of toxicity in Wistar rats

Abstract

In Nigeria, plant-based herbal medicines are vital component of traditional medicine (TM) and their use for the maintenance of health and wellbeing has been a common practice. These TMs are freely used without mandatory safety or toxicological evaluation. Thus, it is necessary to identify plants with toxicity potentials among the plants used for therapeutic purposes in the country. This study investigated effect of ethanolic leaf extract of Macaranga spinosa Muell-Arg on selected biomarkers of toxicity in Wistar rats. Fifteen Wistar rats of both sexes weighing 96.8 -250 g were divided into three groups comprising of group 1 (control 0.5ml distilled water); group 2 (500 mg/kg b.w Macaranga spinosa Muell-Arg leaf extract) and group 3 (1000 mg/kg b.w Macaranga spinosa Muell-Arg leaf extract). At the end of one week oral administration, animals were sacrificed; blood and tissues samples were taken for biochemical and histopatological investigations respectively. Phytochemicals present were alkaloids, flavonoids, tannins, triterpeneoid/steroids, carbohydrates, cardenolide, and saponins. Urea, sodium ion, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) concentration were significantly elevated in group 3; non-significant increase in creatinine, potassium, bicarbonate, chloride ion and alkaline phosphatase (ALP) concentration in group 2 and 3 compared to group 1. Total protein and triglyceride were significantly decreased in group 3 compared to group 1. Albumin, total and conjugated bilirubin were non-significantly decreased in group 2 and 3 when compared to control group 1. Histological examination of kidney tissue showed no change in kidney histology; liver tissue indicated vacuolar and cytoplasm degeneration, and fatty change. Hart tissues showed normal cardiac myocytes. This study has established that ethanolic leaf extract of Macaranga spinosa Muell-Arg can cause hepatoxicity, mild nephrotoxicity and no significant alteration of lipid profile in Wistar rats. Therefore, users of this plant in TM should avoid excessive and prolong use, as it can be toxic to the liver.