pentostatin and Trypanosomiasis

The aim of this study was to evaluate the therapeutic efficacy and safety of using 3'deoxyadenosine (Cordycepin - adenosine analogue) combined with deoxycoformycin (Pentostatin - an adenosine deaminase inhibitor) in mice infected with Trypanosoma evansi. We show that the combination of Cordycepin (2.0 mg kg(-1)) and Pentostatin (0.2, 0.5, 1.0, 2.0 mg kg(1)) is effective in the clearance of T. evansi, although at the higher concentrations of Pentostatin 2 mg kg(-1) some toxicity was observed in the liver and kidney. Since the Cordycepin 2.0 mg kg(-1) and Pentostatin 0.2 mg kg(-1) combination was effective and had low toxicity, we recommend this as a therapeutic option for a T. evansi mouse model.

Topics: Animals; Deoxyadenosines; Dose-Response Relationship, Drug; Female; Humans; Mice; Mice, Inbred BALB C; Pentostatin; Trypanocidal Agents; Trypanosoma; Trypanosomiasis

This study aimed to verify the effect of 3'-deoxyadenosine and deoxycoformycin on hematologic parameters and adenosine deaminase (ADA) activity in plasma and brain of mice infected with Trypanosoma evansi. Seventy animals were divided into seven groups, which were divided into two subgroups each for sampling on days 4 and 8 post-infection (PI). The groups were composed of three uninfected groups (A-C), namely, not-treated (A), treated with 3'-deoxyadenosine (B), and treated with deoxycoformycin (C) and four infected groups, mice with T. evansi (D-G), namely, not-treated (D), treated with 3'-deoxyadenosine (E), treated with deoxycoformycin (F), and treated with a combination 3'-deoxyadenosine and deoxycoformycin (G). Hematological parameters and ADA activity were evaluated in plasma and brain. Animals in groups B and C exhibited a reduction in the levels of plasma total protein compared group A. Animals in groups D and F showed changes in the hematological parameters. The ADA activity significantly reduced in the animals of groups C, D, F and G. Mice in the group E presented increased ADA activity in plasma. Therefore, we conclude that the treatment interferes significantly in the hematologic parameters in mice infected with T. evansi. On the other hand, when the ADA inhibitor was used we observed a significant decrease in the values of hematocrit, total erythrocytes, and hemoglobin concentration. The deoxycoformycin was able to inhibit the ADA activity of parasite thus it may be one of the mechanisms of efficacy of this treatment.

Topics: Adenosine Deaminase; Adenosine Deaminase Inhibitors; Animals; Blood Proteins; Brain; Deoxyadenosines; Dose-Response Relationship, Drug; Erythrocyte Count; Female; Hematocrit; Hemoglobins; Leukocyte Count; Mice; Parasitemia; Pentostatin; Trypanosoma; Trypanosomiasis

The aim of this study was to evaluate the anti-trypanosomal effect of treatment with 3'-deoxyadenosine (cordycepin) combined with deoxycoformycin (pentostatin: inhibitor of the enzyme adenosine deaminase) in vitro by using mice experimentally infected with Trypanosoma evansi. In vitro, a dose-dependent trypanocidal effect of cordycepin was observed against the parasite. In the in vivo trials, the two drugs were used individually and in combination of different doses. The drugs when used individually had no curative effect on infected mice. However, the combination of cordycepin (2 mg kg-1) and pentostatin (2 mg kg-1) was 100% effective in the T. evansi-infected groups. There was an increase in levels of some biochemical parameters, especially on liver enzymes, which were accompanied by histological lesions in the liver and kidneys. Based on these results we conclude that treatment using the combination of 3'-deoxyadenosine with deoxycoformycin has a curative effect on mice infected with T. evansi. However, the therapeutic protocol tested led to liver and kidney damage, manifested by hepatotoxicity and nephrotoxicity.

Topics: Animals; Deoxyadenosines; Dose-Response Relationship, Drug; Drug Therapy, Combination; Female; Mice; Pentostatin; Polymerase Chain Reaction; Trypanocidal Agents; Trypanosoma; Trypanosomiasis

Growth on Trypanosoma musculi in the murine host was limited by the availability of host purines. A portion of the spleen cells of infected mice (many of them granulocytes) displayed high levels of adenosine deaminase (ADA) and purine nucleoside phosphorylase, probably as a compensatory response to extracellular purine deficiency. Injections of adenosine or 2-deoxycoformycin stimulated significant increases in the growth of parasites. 2-Deoxycoformycin treatment also diminished parasite-induced splenomegaly. Treatment of mice with polyethylene glycol-modified ADA, a slowly catabolized form of ADA, had no effect on the course of T. musculi infection, indicating that the parasites can utilize purines other than adenosine. The apparent competition between parasites and host cells for available purines suggests that depletion of extracellular purines should be considered as an approach to treating extracellular trypanosome infections.

Topics: Adenosine Deaminase; Animals; Bone Marrow; Coformycin; Fructose-Bisphosphate Aldolase; Lymph Nodes; Mice; Pentostatin; Purine-Nucleoside Phosphorylase; Purines; Spleen; Trypanosoma; Trypanosomiasis