ABSTRACT
Malaria is a devastating parasitic disease which caused around 216 million cases and 445,000 deaths worldwide in 2016. This might be attributed to a wide spread of drug resistant parasites. The plant Aloe megalacantha is indigenous to Ethiopia where the sap of the leaves is traditionally used for the treatment of malaria. This study was aimed at evaluating the antimalarial effect of leaf latex and isolates obtained from Aloe megalacantha against chloroquine sensitive Plasmodium berghei ANKA strain in Swiss albino mice. Peters' 4-day suppressive test method was used to test the antimalarial activity of both leaves latex and isolates. Three isolates were obtained using thin layer chromatography and were coded as AM1, AM2, and AM3 in ascending order of their retention factor. After treatment of Plasmodium berghei infected mice with leaf latex of Aloe megalacantha for four days at 100, 200, and 400 mg/kg, it shows 30.3%, 43.4%, and 56.4% suppression of the parasite growth, respectively. 32.3%, 51.3%, and 67.4% chemosuppression after treatment with AM1, 39.8%, 50.6%, and 64.2% chemosuppression after treatment with AM2, and 52.6%, 69.4%, and 79.6% chemosuppression after treatment with AM3 were observed at doses of 100, 200, and 400 mg/kg/day, respectively. The observed parasite suppression of leaves latex and isolates was statistically significant (P<0.05) as compared to negative control. Moreover, both the leaves latex and isolates were also observed to prevent Plasmodium berghei induced body weight loss and hypothermia and increased the survival time of Plasmodium berghei infected mice as compared to the negative control. Hence, the present study supports the traditional claim of the plant for the treatment of malaria.
ABSTRACT
BACKGROUND: Aloe megalacantha Baker (Xanthorrhoeaceae) is one of the Aloe species widely distributed in Ethiopia. The leaf latex of the plant is used for treatment of wounds, inflammation, and other multiple ailments in Ethiopian traditional medicine. PURPOSE: The aim of this study was to evaluate in vivo wound healing and anti-inflammatory activities of the leaf latex of Aloe megalacantha in mice. METHODS: The wound healing activity of the leaf latex of the plant was studied topically by incorporating the latex in simple ointment base in a concentration of 5% (w/w) and 10% (w/w) using excision and incision models. In these models, wound contraction, period of epithelialization, and breaking strength of the wounded skin were determined. Carrageenan induced inflammation of paw model was also used to assess the anti-inflammatory activity of the leaf latex at doses of 200 mg/kg, 400mg/kg, and 600 mg/kg. The level of inflammation suppressions were measured at 1, 2, 3, and 4 hrs after carrageenan injection, and then the percentages of inflammation inhibition were computed as compared with the negative control. RESULT: In both wound models, mice treated with 5% (w/w) and 10% (w/w) latex ointment showed a significant (p<0.05) increment in the rate of wound contraction, reduction in epithelialization time, and higher skin breaking strength. Besides, the latex also exhibited a dose-dependent significant (p<0.05) reductions of inflammation as compared to negative control groups. CONCLUSION: The overall results of this study demonstrate that the leaf latex of A. megalacantha possesses wound healing and anti-inflammatory activities which can scientifically substantiate the traditional use of the plant as a wound healing agent.
