Sub-Acute Oral Toxicity Study of Ethanol Extract of Oroxylum Indicum Leaf in C57BL/6 Mice

Abstract

Oroxylum indicumalso known as ‘pucukbeko’ in Malaysia is often consumed as raw salad (ulam) due to the belief that the plant has numerous therapeutics activities that could improve health. Despite its medicinal potential,however, there has been very limited data on the plant’s safety and toxicity profile particularly for long term consumption. More depth insight and evidence-based studies are needed to verify its safety as a potential herb. Therefore, this study aims to investigate sub acute oral toxicity of ethanol extract of O. indicum in C57BL/6 male mice. Twenty-five mice (n=5) were orally administered at single dose of normal saline (control), vehicle (5% DMSO), extracts (100, 200 and 500 mg/kg bw), respectively in accordance with OECD Guideline 420 for 28 days. Liver, kidneys, heart, lungs, testes, spleen,and blood samples were collected to determine the effects of the extract on the relative organ weight, tissue changes, and blood profile alterations in the end of the study. The sub-acute toxicity results demonstrated no lethal effects and abnormal behavioural changes in mice treated with an expansion dose up to a maximum of 500 mg/kg. No significant (p>0.05) changes in body weights, relative organ weight and haematological evaluation. Nevertheless, there were significant differences (p<0.05) in the urea, mean corpuscular volume (MCV), and alanine transaminase (ALT) values but the levels were still within the acceptable range. Histopathological analysis of the liver and kidney tissues also revealed no striking lesions. This study displays that mice treated with an increasing dose ofO. indicum leaf ethanolic extract up to a maximum 500mg/kg bw did not cause any toxicological effects and considered safe to be consumed and used for therapeutic purposes.