Acute and Sub-acute toxicity of the aqueous leaf extract of Lantana trifolia (Verbenaceae) in experimental rodents

Abstract

Lantana trifolia, a plant of the Verbenaceae family, is traditionally used to treat several diseases; however, empirical data to validate its toxicity profile and safety is lacking. Thus, this study investigated the qualitative phytochemical composition, acute and sub-acute toxicity of the aqueous leaf extract of L. trifolia to validate its ethnomedicinal usage. Methods: Qualitative phytochemical analysis of the studied plant extract was performed based on standard procedures to appraise its pharmacological value. Acute oral toxicity of the study extract was investigated at dose levels of 300 mg/Kg BW and 2000 mg/Kg BW according to guideline 423 described by the Organization for Economic Co-operation (OECD) for 14 days. Sub-acute oral toxicity of the studied plant extract was investigated at three dose levels (250 mg/Kg BW, 500 mg/Kg BW, and 1000 mg/Kg BW) in Swiss albino mice based on the OECD guideline number 407 for 28 days, after which haematological, biochemical, and histological traits were determined. Results: Phytochemical screening revealed the presence of tannins, saponins, phenolics, terpenoids, flavonoids, alkaloids, and reducing sugars. In an acute oral toxicity study, the aqueous leaf extract of L. trifolia demonstrated a median lethal dose (LD50) of >2000 mg/Kg BW, depicting its safety. Following sub-acute oral toxicity, the urea levels in female mice which received 1000 mg/Kg BW of the aqueous leaf extract to L. trifolia were significantly elevated compared to those of the control group mice (P<0.05). Also, significantly higher platelet counts were observed in all the extract-treated mice compared with those of the control group mice (P<0.05). Additionally, the mice administered with 1000 mg/Kg BW of the studied plant extracts demonstrated diffuse tubular epithelium degeneration, indicating nephrotoxicity and a dose-related hepatocyte degeneration, indicating hepatotoxicity. Conclusions: The aqueous leaf extract of L. trifolia may be relatively non-toxic when administered orally for a short period. The aqueous leaf extract of L. trifolia induces nephrotoxicity and hepatotoxicity in experimental mice when administered sub-acutely at a dose of ≥1000 mg/Kg BW.