Abstract

Africa is a vast reservoir of medicinal plants which need substantial research to understand their therapeutic potential for safe use. Tithonia diversifolia (TD) and Moringa oleifera (MO) are two such plants commonly used in South-west Nigeria for their therapeutic properties. This study therefore evaluated the effects of single and combined aqueous leaf extracts of both plants on hematological, biochemical and histopathological indices of albino rats aimed at providing baseline information on their systemic health impact when orally administered. Thirty albino rats of both sexes were allotted to 6 groups of 5 rats each and given the extracts: Group I (control) distilled water only; Groups II to VI-200 mg/kg TD; 200 mg/kg MO; 200 mg TD + 200 mg MO; 400 mg TD + 400 mg MO and 800 mg of TD + 800 mg MO respectively. These were orally administered daily for 14 days at the end of which blood samples, liver and kidney tissues were collected. Body weights were measured weekly. Results were compared with rats administered distilled water only. No significant differences (p≥ 0.05) were observed in the body weights of the rats. Alterations in the values of hematological indices were observed within the treatment groups showing significant differences (p<0.05) when compared with control. Significant differences (p< 0.05) were observed in the values of serum biochemical indices when compared with the control. However, the combination of both extracts above 200 mg/kg resulted in injury to the liver and kidney tissue indicating toxicity at high doses. This study demonstrated that 200 mg/kg of the combined leaf extracts is safe and effective for use.

Key words: Albino rats, haematology, histopathology, serum biochemistry, Moringa oleifera, Tithonia  diversifolia.