Curcumin pre-treatment modulate the activities of adenine nucleotide and nucleoside degradation enzymes in lymphocyte of rats infected with Trypanosoma evansi.

This study aimed to evaluate nucleoside triphosphate diphosphohydrolase (NTPDase) and adenosine deaminase (ADA) activities in lymphocytes from rats supplemented or not with curcumin 30 days prior to experimental infection with Trypanosoma evansi. Thirty-two adult male Wistar rats were divided in four groups. The pre-infection group 20 (PreI20) received orally 20 mg/kg of curcumin and pre-infection group 60 (PreI60) received orally 60 mg/kg of curcumin for 30 days prior inoculation with T. evansi. The infected e non-infected control groups received only oral vehicle for 30 days. Trypanosoma evansi infected groups were inoculated intraperitoneally with 0.2 ml of blood with 1 × 106 parasites. After inoculation the treatment of the groups continued until the day of euthanasia (15 days). The results showed that curcumin pre-treatment, with both doses, reduced (P < .05) NTPDase and increased (P < .05) ADA activity in lymphocytes of treated groups when compared to untreated and infected animals (control). The results of this study support the evidence that the regulation of ATP and adenosine levels by NTPDase and ADA activities appear to be important to modulate the immune response in T. evansi infection, once the treatment with curcumin maintained the NTPDase activity reduced and enhanced ADA activity in lymphocytes. It is possible to conclude that the use of curcumin prior to infection with T. evansi induces immunomodulatory effects, favoring the response against the parasite.

Anthocyanins suppress the secretion of proinflammatory mediators and oxidative stress, and restore ion pump activities in demyelination.

The aim of this study was to investigate the protective effect of anthocyanins (ANT) on oxidative and inflammatory parameters, as well as ion pump activities, in the pons of rats experimentally demyelinated with ethidium bromide (EB). Rats were divided in six groups: control, ANT 30 mg/kg, ANT 100 mg/kg, EB (0.1%), EB plus ANT 30 mg/kg and EB plus ANT 100 mg/kg. The EB cistern pons injection occurred on the first day. On day 7, there was a peak in the demyelination. During the 7 days, the animals were treated once per day with vehicle or ANT. It was observed that demyelination reduced Na(+),K(+)-ATPase and Ca(2+)-ATPase activities and increased 4-hydroxynonenal, malondialdehyde, protein carbonyl and NO2plus NO3 levels. In addition, a depletion of glutathione reduced level/nonprotein thiol content and a decrease in superoxide dismutase activity were also seen. The dose of 100 mg/kg showed a better dose-response to the protective effects. The demyelination did not affect the neuronal viability but did increase the inflammatory infiltrate (myeloperoxidase activity) followed by an elevation in interleukin (IL)-1ß, IL-6, tumor necrosis factor-α and interferon-γ levels. ANT promoted a reduction in cellular infiltration and proinflammatory mediators. Furthermore, ANT restored the levels of IL-10. Luxol fast blue staining confirmed the loss of myelin in the EB group and the protective effect of ANT 100 mg/kg. In conclusion, this study was the first to show that ANT are able to restore ion pump activities and protect cellular components against the inflammatory and oxidative damages induced by demyelination.

Pre-treatment with curcumin modulates acetylcholinesterase activity and proinflammatory cytokines in rats infected with Trypanosoma evansi.

The potent activity against Trypanosomes and health beneficial effects of curcumin (Cur) has been demonstrated in various experimental models. In this study, we evaluated the in vivo effect of Cur as trypanocide and as potential anti-inflammatory agent, through the evaluation of immunomodulatory mechanisms in rats infected with Trypanosoma evansi. Daily oral Cur was administered at doses of 0, 20 or 60mg/kg as preventive treatment (30 and 15days pre infection) and as treatment (post infection). The treatment of the groups continued until the day of euthanasia. Fifteen days after inoculation, parasitemia, plasma proinflammatory cytokines (IFN-γ, TNF-α, IL-1, IL-6), anti-inflammatory cytokines (IL-10) and blood acetylcholinesterase activity (AChE) were analyzed. Pretreatment with Cur reduced parasitemia and lethality. Cur inhibited AChE activity and improved immunological response by cytokines proinflammatory, fundamental during T. evansi infection. We found that Cur is not so important as an antitrypanosomal activity but as immunomodulator agent. These findings reveal that the preventive use of Cur stimulates anti-inflammatory mechanisms, reducing an excessive inflammatory response.

Biochemistry detection of acetylcholinesterase activity in Trypanosoma evansi and possible functional correlations.

Several chemical and immunohistochemical techniques can be used for the detection of acetylcholinesterase (AChE) activity. In this experiment we aimed to detect AChE activity in Trypanosoma evansi. For this, the parasites were isolated from the blood of experimentally infected rats using a DEA-cellulose column. Enzymatic activity was determined in trypomastigote forms at 0, 0.2, 0.4, 0.8 and 1.2 mg/mL of protein concentrations by a standard biochemical protocol. At all concentrations tested, the study showed that T. evansi expresses the enzyme AChE and its activity was proportional to the concentration of protein, ranging between 0.64 and 2.70 µmol of AcSCh/h. Therefore, we concluded that it is possible to biochemically detect AChE in T. evansi, an enzyme that may be associated with vital functions of the parasite and also can be related to chemotherapy treatments, as further discussed in this article.