Toxicity assessment of the ripe fruit of Cucumis metuliferus in Swiss albino mice

Cucumis metuliferus E. Mey. Ex. Naudin have been shown to alter haematological and serum biochemical values of cockerels and rats. These alterations may possess hepatoprotective, nephroprotective, and/or cause toxicity to the various organs in the animal models that could lead to unwanted side effects. However, there is paucity of information on its toxicological profile in mice. Therefore, this study investigates the in-vivo toxicological effects of the ripe fruits of Cucumis metuliferus in Swiss albino mice. The dried ground powder of Cucumis metuliferus (CM) was extracted with distilled water to obtain the crude aqueous extract (AE), which was used to investigate the body weight change, acute toxicity (24 h), and sub-acute toxicity (28 days) studies in Swiss albino mice. Mice were orally dosed with AE at 200, 400, and 600 mg/kg. Blood and serum were collected on day 0 (before extract treatment) and after treatment on days 7, 14, 21, and 28 for determination of haematological parameters and serum biochemical respectively. The mice were humanely sacrifice on day 28 after blood collection, and liver, kidneys, and intestines were harvested for histopathology. The extract showed no significant (p ≥ 0.05) change in body weights of control and treated mice when compared to their day 0. But, it significantly (p ≤ 0.05) increased red blood cell, packed cell volume, neutrophils, mean corpuscular volume, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, globulin, serum sodium and chloride, while it significantly (p ≤ 0.05) decreased total white blood cells, lymphocytes, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, total protein, albumin, direct bilirubin, urea, and creatinine. Treated mice showed no sign of acute toxicity or mortality within 24 h. But, prolonged administration (sub-acute study) showed congestion in the liver at all tested doses, while necrosis of hepatocytes was only seen at 400 mg/kg. The result obtained from this study revealed the probable safety of the fruit of Cucumis metuliferus within 24 h. However, prolonged administration of the extracts may cause injury to the liver or kidney. Thus, administration of unrefined extracts may require caution.