Anti-infective Activities of Secondary Metabolites from Vitex pinnata.

The phytochemical investigation of Vitex pinnata led to the isolation of a mixture of steroids β-sitosterol and stigmasterol (1a and 1b) and three known flavonoid identified as 5-hydroxy-3, 7, 4’-trimethoxyflavone (2), 5-hydroxy-7,4’-dimethoxy-flavone (3) and 5-hydroxy-3,3’,4’,7-tetramethoxyflavone (4). The structures of all isolated compounds were carried out by NMR and mass spectrometry. The isolated compounds were evaluated for their anti-infective activities against Trypanosoma brucei brucei and Mycobacterium marinum. Compound 1-4 showed moderate antitrypanosomal activity with MIC values of 6.25μg/ml, 19.0, 21.0 and 17.0μM, respectively while no activity observed on anti-mycobacterial. This study is the first to report the presence of three flavones and their antitrypanosomal activity from V. pinnata.

Studies of the antitrypanosomal and toxicological properties of Anogeissus leiocarpus (Dc.) Guill. & Perr. (Combretaceae) and Vitellaria paradoxa C. F. Gaertn (Sapotaceae) in mice / Estudios de las propiedades antitripanosómicas y toxicológicas de Anogeissus leiocarpus (Dc). Guill. & Perr. (Combretaceae) y Vitellaria paradoxa C. F. Gaertn (Sapotaceae) en ratones

African animal trypanosomosis (AAT) is a disease of concern with ravaging effects on the health of both animals and livestock in tropical Africa. This study investigates the anti-trypanosomal activities of Anogeissus leiocarpus (ALE) and Vitelleria paradoxa (VPE) stem bark extracts and also determines the toxicological profile of the active plant, with a view to establishing the anti-trypanosomal potential and safety of the plants. Laboratory mice (19 g – 26 g) and rats (140 g – 165 g) obtained from the Animal house, Faculty of Pharmacy, OAU, Ile-Ife were used for the study. The animals were treated according to the standard set criteria for animal use and care. VPE showed neither trypanocidal nor trypanostatic activities while ALE was found to be trypanostatic at 62.5 and 125 mg/kg body weight. However, the partitioned aqueous fraction of ALE was found to demonstrate comparable anti-trypanocidal effect as Diminal (standard agent). In conclusion, the ethanolic extract of A. leiocarpus possesses antitrypanosomal effect through the relative suppression or delay in parasite establishment in trypanosome-infected mice. The toxicological study of A. leiocarpus stem bark extract revealed that it is relatively safe for use in cattle and other grazing animals.

La tripanosomiasis africana de los animales es una enfermedad de preocupación que causa estragos sobre la salud de los animales y el ganado en África tropical. Este estudio investiga las actividades anti-tripanosomal de Anogeissus leiocarpus (ALE) y Vitelleria paradoxa (VPE) del tallo y extractos de corteza. También determina el perfil toxicológico de la planta activa, con el fin de establecer el potencial anti-tripanosomal y la seguridad de las plantas. Ratones de laboratorio (19 g - 26 g) y ratas (140 g - 165 g) obtenidos del Bioterio de la Facultad de Farmacia de la OUA, se utilizaron para el estudio. Los animales fueron tratados de acuerdo con los criterios estándar establecido para el uso y cuidado de animales. VPE mostró actividades no tripanocidas ni tripanostáticas mientras que en ALE se encontró que era tripanostático a 62,5 y 125 mg/kg de peso corporal. Sin embargo, se encontró que la fracción acuosa de ALE demostró un efecto anti-tripanocida comparable como Diminal (agente estándar). En conclusión, el extracto etanólico de A. leiocarpus posee efecto sobre tripanosomas a través de la supresión relativa o retraso en la creación de parásitos en ratones infectados con tripanosomosis. El estudio toxicológico del extracto de corteza del tallo A. leiocarpus reveló que es relativamente seguro para su uso en el ganado y otros animales de pastoreo.

Taxonomic characterization and isolation of antitrypanosomal compound from Streptomyces sp. FACC-A032 isolated from Malaysian forest soil

Aims: The present study is aimed at taxonomic characterization and isolation of active compound MS01 from Streptomyces sp. FACC-A032 which exhibited strong antitrypanosomal activity (IC50 0.02 μg/mL). Methodology and results: Isolate FACC-A032 was characterized based on its cultural, morphological, physiological and genomic properties. Isolate FACC-A032 was tentatively identified as Streptomyces sp. Biochemical analysis of diaminopimelic acid (DAP) isomer of whole-cell hydrolysates further confirmed the isolate FACC-A032 that contained LL-DAP isomer as species belonging to the genus Streptomyces. The inoculum for submerged cultures of isolate FACCA032 was prepared from cultures on ISP2 agar. After eight days of growth at 28  2 °C and 200 rpm in fermentation medium M3, fermentation broth was extracted with butanol and the crude extracts (solvent layer) were separated and dried in vacuo. Further studies were carried out to isolate the active compound from the culture extracts of isolate FACCA032. Using bioassay-guided isolation, crude extract was partitioned based on different polarity. After which, the resulting elutes were tested for antitrypanosomal activity. The active fraction was analyzed with HPLC-DAD analysis. Based on the analysis, major peak in the active fraction was collected using HPLC preparative. Active compound MS01 was isolated and structure elucidated using NMR spectroscopy. Conclusion, significance and impact of study: Bioassay-guided isolation techniques used in this study had discovered an active antitrypanosomal compound, staurosporine, from Streptomyces sp. FACC-A032. This is the first discovery of staurosporine, a protein kinase inhibitor, from Malaysian soil actinobacteria Streptomyces sp. Therefore, the study demonstrated the potential of Malaysian soil actinobacteria as antitrypanosomal therapeutic agent.

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.

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.

In vitro activity of thienyl-2-nitropropene compounds against Trypanosoma cruzi

The in vitro activity of four 2-nitropropene derivatives, 1-(3-benzothienyl)-2-nitropropene (N1), 1-(3-thienyl)-2-nitropropene (N2), 1-(5-bromo-2-thienyl)-2-nitropropene (N3) and 1-(4-bromo-2-thienyl)-2-nitropropene (N4), were tested against cultures of the parasite Trypanosoma cruzi. Cytotoxicity studies were performed using Vero cells. The blood trypomastigotes, amastigotes and epimastigotes showed differential degrees of sensitivity towards the four tested compounds; the highest activity against the epimastigotes and blood tripomastigotes was exhibited by N1, followed by N3, N4 and finally N2. In contrast, whereas the compounds N1, N3 and N4 exerted similar magnitudes of activity against amastigotes, N2 was found to be a much less potent compound. According to our results, the compound N1 had the highest level of activity (IC50: 0.6 ìM) against epimastigotes.

The BENEFIT trial: testing the hypothesis that trypanocidal therapy is beneficial for patients with chronic Chagas heart disease

Among the pathophysiological derangements operating in the chronic phase of Chagas disease, parasite persistence is likely to constitute the main mechanism of myocardial injury in patients with chronic chagasic cardiomyopathy. The presence of Trypanosoma cruzi in the heart causes a low-grade, but relentless, inflammatory process and induces myocardial autoimmune injury. These facts suggest that trypanocidal therapy may positively impact the clinical course of patients with chronic Chagas heart disease. However, the experimental and clinical evidence currently available is insufficient to support the routine use of etiologic treatment in these patients. The BENEFIT project - Benznidazole Evaluation for Interrupting Trypanosomiasis - is an international, multicenter, double-blind, placebo-controlled trial of trypanocidal treatment with benznidazole in patients with chronic Chagas heart disease. This project is actually comprised of two studies. The pilot study investigates whether etiologic treatment significantly reduces parasite burden, as assessed by polymerase chain reaction-based techniques and also determines the safety and tolerability profile of the trypanocidal drug in this type of chagasic population. The full-scale study determines whether antitrypanosomal therapy with benznidazole reduces mortality and other major cardiovascular clinical outcomes in patients with chronic Chagas heart disease.