Evaluation of antitrypanosomal properties and apoptotic effects of ochrolifuanine from Dyera costulata (Miq.) Hook.f against Trypanosoma brucei brucei

@#Trypanosoma brucei parasites are flagellated kinetoplastid protozoan which is responsible for Human African Trypanosomiasis (HAT). Current chemotherapy drugs have a number of side effects and drug resistance has emerged as a major issue in current treatment. Active bisindole alkaloid compound ochrolifuanine was previously isolated from the leaves of Dyera costulata. In vitro antitrypanosomal activity of ochrolifuanine against Trypanosoma brucei brucei strain BS221 showed strong activity with an IC50 value of 0.05 ± 0.01 µg/ml. We compared the effect of ochrolifuanine and reference compound staurosporine in T. b. brucei apoptosis. The apoptosis-inducing activity of ochrolifuanine was evaluated using TUNEL assay and cell cycle analysis. Trypanosoma brucei brucei was shown to undergo apoptotic cells death as demonstrated by the appearance of several conical hallmarks of apoptosis. Ochrolifuanine was found to induce apoptosis in parasites in a dose- and time-dependent manner. The cell cycle study revealed 0.025 and 0.05 µg/ml of ochrolifuanine arrested the growth of T. b. brucei at two different growth phases (G0/G1 and in S phases). While at concentration 0.10 µg/ml arrested at the G2/M phase. In conclusion, the results indicate that ochrolifuanine displayed an antitrypanosomal effect on T. b. brucei by inducing apoptosis cell death and causing the arrest of parasite cells at different growth phases. The results suggested that ochrolifuanine may be a promising lead compound for the development of new chemotherapies for African trypanosomiasis.

In vitro and In vivo Antitrypanosomal Effects of Petroleum Ether, Chloroform and Methanol Extracts of Artemisia maritima Linn.

Petroleum ether, chloroform and methanol extracts of the whole plant of Artemisia maritima Linn were studied in vitro and in vivo for antitrypanosomal activity against Trypanosoma brucei brucei in Swiss albino mice. The extracts were also screened for phytochemicals/secondary metabolites. All the extracts showed trypanocidal activity against T. brucei brucei in vitro with the petroleum ether extract showing the highest activity. The in vivo study revealed that only the chloroform extract A. maritima exhibited antitrypanosomal activity. This extract at a dose of 100mg/kg body weight significantly (p<0.05) reduced the parasitemia in T. brucei brucei infected mice when compared with the other treatment groups. The chloroform extract of A. maritima at this dose reduced the level of parasitemia to 26%. This reduction in the level of parasitemia is statistically significant (p<0.05) compared to the other treatment groups and the untreated control group. The result of the phytochemical analysis revealed that the extracts contain secondary metabolites like flavonoids, terpenoids, steroids, anthraquinones and alkaloids. The presence of these secondary metabolites in this plant might be responsible for the antitrypanosomal activity exhibited by its extracts.

In vitro and in vivo Antitrypanosomal Effects of Methanol and Aqueous Extracts of Picralima nitida.

The methanol and aqueous extracts of the leaves, fruits, seeds, stem bark and roots of Picralima nitida were studied in vitro and in vivo for activity against Trypanosoma brucei brucei in Swiss albino mice. Phytochemicals studies were also conducted for all the plant extracts. The methanol extracts showed appreciably high in vitro and in vivo antitrypanosomal activities compared to the aqueous extracts of the plant. The methanol extract of the root exhibited the highest in vitro antitrypanosomal activity followed by the methanol extract of seed of Picralima nitida. Motility of Trypanosoma brucei brucei was stopped by the methanol extract of the root after 10 min, while the methanol extract of the seed of Picralima nitida stopped the motility of Trypanosoma brucei brucei at 15 min. The methanol extract of the root of Picralima nitida showed the highest in vivo antitrypanosomal activity at 100 mg/kg body weight. The extract cleared the parasite completely from the T. brucei brucei infected Swiss albino mice after day 3 of treatment. There was a statistically significant difference (p<0.05) when the level of parasitemia of the animals treated with the methanol extract of the root of Picralima nitida were compared with the other treatment groups and the untreated control. The phytochemicals detected in these extracts are tannins, flavonoids, alkaloids, steroids, terpenoids, saponins and cyanide glycosides. The in vitro and in vivo antitrypanosomal activity exhibited by these extracts might be attributed to these phytochemicals.

Effect of diminazene aceturate, levamisole and vitamin C combination therapy in rats experimentally infected with Trypanosoma brucei brucei

OBJECTIVE@#To investigate the effect of diminazene aceturate (DA) alone or in combination with either levamisole and/or Vitamin C in albino rats experimentally infected with Trypanosoma brucei brucei.@*METHODS@#Thirty adult male albino rats, randomly assigned into 6 groups (A-F) of 5 rats each were used. They were either infected with 1×10(6) trypanosomes intraperitoneally (groups A-E) or uninfected (group F). The different groups were treated respectively as follows: group A-with 3.5 mg/kg DA; group B-3.5 mg/kg DA and 7.5 mg/kg levamisole; group C-3.5 mg/kg DA and 100 mg/kg vitamin C; and group D-3.5 mg/kg DA and 7.5 mg/kg levamisole and 100 mg/kg vitamin C. Group E was left untreated. Parameters assessed include: rectal temperature, body weight changes, packed cell volume (PCV), Haemoglobin concentration (Hb), total leucocyte count (TLC) differential leucocyte count (DLC), parasitaemia, clinical signs and survivability.@*RESULTS@#Average pre-patent period of 5 days was recorded. Parasites in the blood were cleared in all treated groups (A-D) within 48 hours post treatment (PT). Untreated rats in group E died between 25 and 32 days post infection (PI). Relapse was not recorded in all the treated groups (A-D). The initial reduction in PCV, Hb, TLC and increases in rectal temperature following infection were reversed by the treatments. The rats that received drug combinations (groups B, C and D) showed faster and higher recovery rates than the uninfected control and group A.@*CONCLUSIONS@#Levamisole and/or Vitamin C combination with DA were more effective in the treatment of rats infected with Trypanosoma brucei brucei.

Xylopioxyde and other bioactive kaurane-diterpenes from Xylopia aethiopica Dunal (Annonaceae).

A new cytotoxic ent-kaurane-type diterpene named xylopioxyde (16,17-epoxy-15-oxo-ent-kauran-19-oic acid) has been isolated from the fruits of Xylopia aethiopica Dunal (Annonaceae) together with three known compounds, namely 15α-acetoxy-ent-kaur-16-en-19 oic acid (xylopic acid), 15-oxo-ent-kaur-16-en-19-oic acid and ent-kaur-16-en-19-oic acid. Xylopic acid, obtained in a good amount, has been successively converted in moderate to good yields into 15-hydroxy-ent-kaur-16-en-19-oic acid, 15-oxo-ent-kaur-16-en-19-oic acid and two new selective trypanocidal stereoisomers of 15-acetoxy-16,17-ent-epoxy-kauran-19-oic acid, respectively. All the compounds except the synthetic epoxides displayed cytotoxic effects on the mammalian fibroblast cell line MRC-5 as well as inhibitory effects on the growth of the bloodstream forms of Trypanosoma brucei brucei cells (strain 241).

Anti-trypanosomal effect of Peristrophe bicalyculata extract on Trypanosoma brucei brucei-infected rats

Objective: To investigate the in vitro and in vivo effect of whole plant extracts of Peristrophe bicalyculata on Trypanosoma brucei brucei-infected rats. Methods: The experiment was divided into two phases: In the first phase, the anti-trypanosomal activity of the hot water, cold water, methanol and butanol extracts of the whole plant were determined by incubating with Trypanosoma brucei brucei. The cold water extract was partially-purified and the anti-trypanosomal activity of the fractions determined. In the second phase, Trypanosoma brucei brucei-infected rats were treated with fraction 2c for nine days. Packed cell volume (PCV), high density lipoprotein (HDL), low density lipoprotein (LDL), total cholesterol (TC), triacylglycerol (TAG), aspartate aminotransferase, alanine aminotransferases (ALT), alkaline phosphatase (ALP), total and direct bilirubin levels were determined at the end of the experiment. Results:Cold water extract immobilized 90%of the parasites after 60 min of incubation, and fraction 2c completely immobilized the parasites after 35 min. It significantly increased PCV in Trypanosoma brucei brucei-infected rats. Decreased TC, TAG, HDL and LDL levels of infected rats increased significantly when rats were treated with the fraction, while elevated levels of total bilirubin and ALT also decreased. The difference in urea, direct bilirubin and ALP was not significant when infected rats were compared to rats in other groups. Conclusions:The ability of the plant to ameliorate the infection-induced biochemical changes calls for detailed investigation of the potentials of the plant for antitrypanosomiasis drug delivery.

Effects of Allium sativum Bulb Extract, Diminazene Aceturate and Their Combination on Parasitaemia, and Biochemical Indices in Rats Experimentally Infected with Trypanosoma Brucei Brucei.

Thirty five clinically healthy albino rats of both sexes weighing between 100 – 120grams were used to study the effects of Allium sativum bulb extract in combination with diminazene aceturate on parsitemia and biochemical indices in trypanosome brucei brucei infection. The rats were divided in to seven groups (A-G) of five rats each. All the infected rats developed Parasitemia five days post infection. Weakness, increase respiratory rate, rough hair coat Biochemical changes at interval and possible deaths were the major parameters which were carefully observed. All the treatment commenced at the onset of parasitemia by day five post infection. Sub therapeutic dose of Allium sativum at 20mg/kg/bw in combination with 1.7mg/kg/bw of diminazene aceturate (Group C),diminazene aceturate at single standard dose of 3.5mg/kg/bw (Group B) caused a significant reduction (P<0.05) in parasitemia. The liver function enzymes ALT AST level in rats infected and not treated showed significant increase liver function enzymes (Group A) while those treated with standard and sub therapeutic dose (Group BCD) respectively. Had their liver function enzymes towards normal, compare with control (Group G).Its trypanocidal activity was assessed through daily examination of blood parasite, sub therapeutic doses of Allium sativum bulb extracts and its combination appear to be more effective in reducing severity of trypanosome brucei brucei infection and provide alternative in reducing the toxicity of existing trypanocide.