MICE

Malaria is an acute, life-threatening parasitic infection caused by protozoan parasites of the genus Plasmodium, posing a significant global health threat. The most virulent form that infects humans is Plasmodium falciparum. Current first-line treatments involve Artemisinin-based combination therapies (ACTs), but the increasing prevalence of antimalarial drug resistance constitutes a major impediment to global malaria control initiatives. Historically, traditional knowledge of indigenous plants has guided the discovery of effective antimalarials, such as quinine and artemisinin, underscoring the urgent need to explore plant-based medicines for alternative therapeutic strategies. Persea americana (avocado), a commercially valuable fruit tree, is used traditionally for malaria treatment. This study aimed to evaluate the methanolic extract of Persea americana seed for its antimalarial activity and acute toxicity level. The overall objective was to scientifically validate the plant’s use for anti-malarial therapy and suggest it as a promising source for new antimalarial compounds. Acute toxicity was assessed in six male Wistar strain mice (6–8 weeks old) using the limit test dose up and down procedure of the Organisation for Economic Cooperation and Development (OECD) guideline 423. Antimalarial activity was tested using the Peter’s 4-day Suppressive test in 20 male Wistar strain mice inoculated intraperitoneally with Chloroquine Sensitive Plasmodium berghei NK65 infected red blood cells. Extract doses of 100, 250, and 500 mg/kg b.wt. were administered orally and daily for four days. Control groups received normal saline vehicle, chloroquine (25 mg/kg b.wt.), or lithium chloride (10 mg/kg b.wt.). In the acute toxicity study (OECD guideline 423), following the administration of 2000 mg/kg b.wt. of the Persea americana seed methanol extract, no mice death was recorded, and no other signs of toxicity were observed during the 14-day period. Therefore, the extract was deemed safe for administration at 2000 mg/kg b.wt.. The findings suggest that the Persea americana seed methanol extract has a low acute toxicity profile, as demonstrated by the safety of administering 2000 mg/kg b.wt. in mice. The antimalarial activity of Persea americana recorded decrease in % Parasitemia in mice and the most significant decrease in the highest dose administered. This validates the traditional use of the plant sample and highlight the Persea americana seed as a promising resource for discovering new antimalarial compounds

Rauvolfia vomitoria is a medicinal plant widely used in traditional African medicine for the management of hypertension, mental disorders, and various other ailments. However, the safety profile of its leaf extracts, which are commonly used, remains inadequately scientifically validated. This study was designed to investigate the acute toxicity of the methanol leaf extract of R. Vomitoria in mice. Fresh leaves were collected, authenticated, air-dried, and macerated in 70% methanol. The extract was concentrated using a rotary evaporator. Phytochemical screening was conducted to identify the bioactive constituents. The acute oral toxicity study was carried out according to the OECD Guideline 425 (Up-and-Down Procedure). Twenty adult albino mice were used and administered single oral doses of the extract ranging from 10 mg/kg to 5000 mg/kg. The mice were observed for behavioural changes and mortality over 24 hours, followed by a 14-day monitoring period. Phytochemical analysis revealed the presence of alkaloids, flavonoids, tannins and saponins. In the acute toxicity test, no mortality was recorded at any of the administered doses, including the limit test dose of 5000 mg/kg. Observed behavioural effects such as scratching, restlessness, and sedation were mild and transient. The median lethal dose (LD₅₀) of the methanol leaf extract was therefore determined to be greater than 5000 mg/kg. The findings indicate that the methanol leaf extract of Rauvolfia vomitoria is practically non-toxic following acute oral administration in mice. This high safety margin provides a scientific basis for the relative safety of its traditional use and supports further investigation into its pharmacological potential. It is recommended that sub-chronic and chronic toxicity studies be conducted to fully elucidate its long-term safety profile.

This study used mouse models to assess the acute toxicity and analgesic effects of Moringa oleifera extract. Acute toxicity was tested by giving different oral dose up to 5000 mg/kg, which resulted in no mortality, showing relative safety. The analgesic efficacy was assessed using acetic acid-induced writhing and formalin-induced paw licking assays. The extract considerably reduced writhing behaviors in a dose-dependent manner (p < 0.05), indicating peripheral analgesic effects. In the formalin test, the extract significantly reduced paw licking time in both neurogenic (early) and inflammatory (late) phases, with significant effects at moderate and high dosages (p < 0.05), indicating wide analgesic and antiinflammatory activities. These data confirm Moringa oleifera extract's potential as a safe and effective analgesic agent. Moringa oleifera's phytochemical components, which include flavonoids, alkaloids, saponins, tannins, and phenolic acids, are thought to work together to provide analgesic and anti-inflammatory benefits. The extract's ability to attenuate nociceptive behaviors in established experimental models backs up its longstanding use in folk medicine to treat pain and inflammation. The findings of this work give experimental confirmation for Moringa oleifera root bark as a promising natural analgesic with a wide range of efficacy, prompting further investigation into its pharmacological mechanisms and possible clinical applications. The extract's analgesic efficacy and safety profile make it a promising lowrisk pain management option