In Vitro And In Vivo Assessment of Theantitrypanosomal Activity of Methanol Leaf Extract of Annona Muricata(Meam) on the Blood Parameters Of Trypanasoma Brucei Brucei Infected Albino Rats

This study investigated the anti trypanosomal activity of the methanol leaf extract of Annona muricata [MEAM] in albino rats experimentally infected with Trypanosoma brucei brucei. A total of 32 adult male albino rats weighing between 78g and 100g were used for the study. They were randomly assigned into 4 groups ¬¬of three rats each for the acute toxicity study and 4 groups [I-IV] of 5 rats each for the In vivo study. Groups I and II were infected intraperitoneally with 1.0 ×106 trypanosomes suspended in 0.2ml Phosphate Buffered Saline[PBS]on day 8 of experiment. Group I was treated with 200 mg/kg of MEAM orally every day for 3 days following detectable parasitaemia [4-5days of post infection]. Group II was treated with 7.0 mg/kg of diminazene aceturate intramuscularly on day 14 of experiment [6 days post infection]. Group III served as the uninfected untreated control while Group IV was uninfected and treated orally with 200mg/kg MEAM. Parameters such as Parasitaemia, Packed cell volume [PCV], Hemoglobinconcentration, Total leucocytes count, Differential leucocytes count. The acute toxicity test and the in vitro anti trypanosomal activity of the extract were studied using standard methods prior to commencement of the study. The results of the acute toxicity test showed the LD 50 of the MEAM to be 447 mg/kg whereas the LC50 of the extract was recorded at 0.01mg/mlin vitro. The pre patent period of infection was 3days. Treatment with diminazene aceturate cleared the Parasitaemia in group II. An overall significant decrease[P< 0.05] in PCV and Hemoglobin was observed in the infected groups. Similarly, a significant decrease [P< 0.05] in total leucocytes count was also seen in the infected groups. Treatment with MEAM showed increased Parasitaemia, indicating that MEAM showed an In vitro anti trypanosomal activity and no anti trypanosomal activity In vivo. It is recommended that parental routes of administration of MEAM should be employed for further studies of anti trypanosomal activity of MEAM.