BACKGROUND: Cerebral malaria is a rapidly developing encephalopathy caused by the apicomplexan parasite Plasmodium falciparum. Drugs currently in use are associated with poor outcome in an increasing number of cases and new drugs are... more
BACKGROUND:
Cerebral malaria is a rapidly developing encephalopathy caused by the apicomplexan parasite Plasmodium falciparum. Drugs currently in use are associated with poor outcome in an increasing number of cases and new drugs are urgently needed. The potential of the medicinal plant Azadirachta indica (Neem) for the treatment of experimental cerebral malaria was evaluated in mice.
METHODS:
Experimental cerebral malaria was induced in mice by infection with Plasmodium berghei ANKA. Infected mice were administered with Azadirachta indica ethanolic extract at doses of 300, 500, or 1000 mg/kg intraperitoneally (i.p.) in experimental groups, or with the anti-malarial drugs chloroquine (12 mg/kg, i.p.) or artemether (1.6 mg/kg, i.p.), in the positive control groups. Treatment was initiated at the onset of signs of brain involvement and pursued for five days on a daily basis. Mice brains were dissected out and processed for the study of the effects of the extract on pyramidal cells' fate and on markers of neuroinflammation and apoptosis, in the medial temporal lobe.
RESULTS:
Azadirachta indica ethanolic extract mitigated neuroinflammation, decreased the severity of brain oedema, and protected pyramidal neurons from apoptosis, particularly at the highest dose used, comparable to chloroquine and artemether.
CONCLUSIONS:
The present findings suggest that Azadirachta indica ethanolic extract has protective effects on neuronal populations in the inflamed central nervous system, and justify at least in part its use in African and Asian folk medicine and practices.
Abstract Objective: The objective of this study is to evaluate the effect of topical application of honey on induced cutaneous leishmaniasis ulcer in 25 hamsters (Mesocircetus auratus) compared with control group of another 25 hamsters... more
Abstract Objective: The objective of this study is to evaluate the effect of topical application of honey on induced cutaneous leishmaniasis ulcer in 25 hamsters (Mesocircetus auratus) compared with control group of another 25 hamsters treated by pentostam injection. Methods: A group of 50 adult male and female hamsters, were inoculated with 1×105 cells/mL of Leishmania major. Culture medium was examined microscopically for promastigotes. Samples of 0.1 ml positive culture were inoculated to the hamster –tail base intradermally. The animasl were checked for lesion. Which were taken impression smear.. Smears were fixed and stained with Giemsa’s. Honey was applied topically to infected lesions of one group of hamsters. The control group were injected with 0.1 mL pentostam intramuscular every other day. Lesions were measured daily by millimeter paper. Results: After two weeks all the inoculated hamsters developed different types of lesions. The 25 group of hamsters treated with honey responded to treatment after one week. The control group treated with pentostam injection showed low response to treatment, it took prolonged time to heal up to 12-16 weeks. Conclusion: Topical dressing of cutaneous leishmaniasis ulcers with honey is very effective and helps in the treatment in a short time as compared with pentostam injection.
Aim of the study: The dichloromethane extract prepared from aerial parts of Ageratum conyzoides L. (Asteraceae), a plant commonly used in folk medicine for a number of illnesses including sleeping sickness, was recently found to exhibit a... more
Aim of the study: The dichloromethane extract prepared from aerial parts of Ageratum conyzoides L. (Asteraceae), a plant commonly used in folk medicine for a number of illnesses including sleeping sickness, was recently found to exhibit a prominent activity (IC50 = 0.78g/mL) against bloodstream forms of Trypanosoma brucei rhodesiense, the etiologic agent of East African Human Trypanosomiasis (East African Sleeping Sickness). This extract also exhibited noticeable activities against Leishmania donovani (Kala- Azar, IC50 = 3.4g/mL) as well as Plasmodium falciparum (Malaria tropica, IC50 = 8.0g/mL). In the current study, we sought for potentially active constituents of Ageratum conyzoides. Materials and methods: Extracts prepared with solvents of different polarity were tested for activity against the above mentioned parasites as well as against Trypanosoma cruzi (Chagas’ disease) and for cytotoxicity using established protocols. The dicholoromethane extract showed the highest level of activity and was chosen for phytochemical studies aimed at the isolation of potential active constituents. Results and conclusion: Five highly methoxylated flavonoids along with the chromene derivative encecalol methyl ether were isolated. All isolated compounds were previously reported from Ageratum conyzoides. While the chromene turned out to be inactive against the tested parasites, the flavonoids showed activity against the protozoan pathogens, some in the lower micromolar range. However, none of these isolated compounds was as active as the crude extract. This is the first report on antiprotozoal activity of this plant species and some of its constituents. The chemical principle accounting for the high activity of the crude extract, however, remains to be identified.
