Evaluation of Active Principles of Ethanol Leaf Extracts of Laportea Aestuans for Analgesic Property in Animal Models

Pain is an unpleasant significant clinical issues globally, and there is growing interest in plant-derived remedies for safer, alternative analgesics due to hepatotoxic effects of NSAIDs. Laportea aestuans has been traditionally used in African ethnomedicine for pain relief, but its analgesic efficacy and active principles remain underexplored. The objectives of the study are to identify the active principles, assess the toxicity effects and evaluate the ethanol leaf extracts of Laportea aestuans for analgesic property in animal models.  Leaves of Laportea aestuans were extracted at 90% ethanol using maceration method, followed by phytochemical screening using Trease and Evans method (2002). Acute toxicity study was assessed in mice with Lorke’s method (1983) following the OECD guidelines (2011). Analgesic effects were evaluated in Swiss mice (16-18g) using thermal stimuli models and acetic acid-induced analgesia. Statistical analysis was carried out using mean ± standard deviation followed by one-way ANOVA at the P-value of <0.05 considered to be significant. The active principles identified from the ethanol leaf extracts are terpenoids, flavonoids, alkaloids, phenolic compounds, tannins, saponins and steroids. The LD₅₀ at maximum dose of 5000mg/kg, was atoxic to the animal models. The ethanol leaf extracts at the doses of 100, 200, and 400mg/kg, significantly reduced hot plate-induced analgesia and writhing responses, compared to the standard; aspirin (10mg/kg) and negative control (distilled water). Laportea aestuans leaf extracts indicated analgesic property which are significantly related to the active principles. This validated its use and safety in African traditional medicine and suggested potential for development as a plant-derived analgesics.