Toxicity evaluation, phytochemical characterization and pharmacological effects of aqueous extracts of Combretum collinum leaves: analgesic, antipyretic, and anti-inflammatory activities in animal models

The leaves of Combretum collinum are traditionally used to treat inflammation and promote wound healing. This study aims to assess the toxicity, phytochemical characterization and evaluate the analgesic, anti-inflammatory, and antipyretic properties of the aqueous extract of Combretum collinum (AECC) leaves in an animal model. The phytochemical analysis was performed using LC-MS and safety assessment (acute and subacute toxicity) of AECC were conducted according to standard scientific procedures (OECD guidelines). Analgesic and anti-inflammatory effects was determined via formalin-induced assay, while the antipyretic activity used turpentine-induced fever model. Diclofenac (15mg/kg) served as a reference drug. No acute toxicity symptoms were observed after the oral administration of AECC at a dose of 2000mg/kg. In the sub-acute study, AECC extract showed no mortality or treatment-related adverse effects on general behavior, body weight, relative organ weights, and hematological and biochemical parameters. The analgesic activity of the AECC extract at 50, 100, and 150mg/kg resulted in a pain response reduction of 40.37 %, 39.89 %, and 40.38 %, respectively, in the acute phase, while the chronic phase demonstrated dose-dependent pain inhibition (p ≤ 0.05). The AECC extract also lowered rectal temperature in the antipyretic activity to 3.14 %, 3.61 %, and 3.86 %, respectively, for the same doses. AECC exhibited anti-inflammatory activity with reductions in formalin-induced paw edema of 0.68 %, 0.69 %, and 0.68 % at 50, 100, and 150mg/kg, respectively. This study concludes that there are no acute or sub-acute toxicity symptoms associated with AECC and demonstrates its analgesic, anti-inflammatory, and antipyretic effects, indicating its potential application as a viable therapeutic agent.