Acute toxicity of Steganotaenia araliacea Hochst ethanolic stem-bark extract on winstar albino rats

Abstract

Acute Oral Toxicity Evaluation of Ethanolic Stem-Bark Extract of Steganotaenia araliacea Hochst in Wistar Albino Rats Chronic kidney disease and acute kidney injury represent major public health challenges in Uganda and across Africa, where access to conventional renal-protective drugs remains limited and costly. Steganotaenia araliacea Hochst (Apiaceae), commonly known as the carrot tree, is widely used in Ugandan traditional medicine for various ailments, including as a diuretic, but its safety profile has not been scientifically established. The present study aimed to evaluate the acute oral toxicity of the ethanolic stem-bark extract of S. araliacea and to determine its median lethal dose (LD50) in Wistar albino rats. The extract was prepared by 96% ethanol maceration of shade-dried stem bark collected in Wakiso District, Uganda. Acute toxicity was assessed following OECD Guideline 425 (Up-and-Down Procedure). Male Wistar albino rats (200–220 g) received single oral doses of 2000 mg/kg or 5000 mg/kg body weight, with a concurrent vehicle control group. Animals were observed for 14 days for mortality, clinical signs, body weight changes, organ weights, gross pathology, and histopathology of liver, kidneys, and stomach. No mortality occurred at any dose up to the limit dose of 5000 mg/kg, resulting in an LD50 > 5000 mg/kg. Transient clinical signs (mild lethargy, increased respiration, abnormal defecation, and partial sleep) were observed within the first 24 hours but resolved completely. An initial body weight reduction was followed by full recovery and normal weight gain. Gross examination revealed no lesions, and organ-to-body weight ratios were comparable to controls. Histopathological analysis showed no significant alterations in liver or kidneys at either dose. Mild gastric epithelial sloughing was noted only at 5000 mg/kg, indicating localized irritation. The ethanolic stem-bark extract of Steganotaenia araliacea is practically non-toxic acutely when administered orally to rats (GHS Category 5 or unclassified). These findings provide the first preclinical safety data supporting the relative short-term safety of this traditionally used plant and lay the foundation for further sub-chronic toxicity, phytochemical, and efficacy studies targeting renal disorders.