An Evaluation of Acute and Sub-Acute Toxicity of Methanolic Root Extract Of Myricasalicifolia A. Rich (Myricaceae) On the Histopathology of the Liver, the Kidney and Some Blood Parameters in Swiss Albino Mice

Background: Myrica salicifolia is a medicinal plant used for the treatment of various human diseases, like malaria, inflammations, infections, diabetes mellitus and gastrointestinal spasm. The aim of this study was to evaluate the acute and sub-acute toxicity effects of methanolic roots extract of the M. salicifolia on the histopathology of the liver, the kidney and some blood and biochemical parameters in mice model.

Methods: Roots of M. salicifolia were collected in October 2016 from Gondar area, northwest Ethiopia. The roots were dried and extracted with 80% methanol. Swiss albino female mice weighing 25-40 g and 8-12 weeks old, were randomly divided into four groups (one control and three experimental). The control group received 0.5 ml of distilled water orally, and the treatment groups were given the methanolic root extract of M. salicifolia using oral gavage at the doses of 100, 200 and 400 mg/kg body weight per day for four weeks. The hematological and biochemical analyses were examined after collecting blood samples from the mice. Liver and kidney were removed, stained and examined for histopathological effects. Following the application of standard procedures, the hematological, biochemical and histopathological features of the experimental groups were compared with the corresponding control group.

Results: No signs of toxicity and mortality were detected during the acute test evaluation at a dose of 2000 mg/kg, signifying that the oral LD₅₀ of the extract was greater than 2000 mg/kg.  The measured values of hematological parameters (red blood cells and mean corpuscular hemoglobin concentration) and biochemical parameters (except glucose) of all treated groups increased significantly (p< 0.05) compared to the control. Moreover, our histopathological finding hardly indicated any toxicity effect of the root extract in liver and kidney.

Conclusion: At the acute toxicity level of administration, the toxicity effect of the plant extract was not detected. Similarly, following the sub-acute test, no significant organ weight and histological changes were identified.  Overall, it can be concluded that oral administration of roots of M. salicifolia extract is relatively safe to mice.