RESUMO
The purpose of the present study was to evaluate the efficacy of the treatment with a recombinant cysteine proteinase from Leishmania, rldccys1, associated with allopurinol or miltefosine on Leishmania (Leishmania) infantum chagasi-infected hamsters. Golden Syrian hamsters infected with L. (L.) infantum chagasi were treated with either miltefosine (46 mg/kg) or allopurinol (460 mg/kg) alone by oral route or associated with rldccys1 (150 µg/hamster) by subcutaneous route for 30 days. Infected hamsters were also treated with miltefosine (46 mg/kg) plus rldccys1 (150 µg/hamster) for 30 days (phase 1) followed by two additional doses of rldccys1 (250 µg/hamster) (phase 2). After the end of treatment, the animals were analyzed for parasite load, body weight, serum levels of immunoglobulins, cytokine expression, and drug toxicity. The data showed a significant decrease of parasite load in infected hamsters treated with allopurinol or miltefosine alone or associated with rldccys1, as well as in those treated with rldccys1 alone. Significantly lower levels of serum IgG were detected in hamsters treated with allopurinol plus rldccys1. The treatment with miltefosine associated with rldccys1 prevented relapse observed in animals treated with miltefosine alone. A significant loss of body weight was detected only in some hamsters treated with miltefosine for 1 month and deprived of this treatment for 15 days. There were no significant differences in transcript expression of IFN-γ and IL-10 in any of treated groups. Neither hepatotoxicity nor nephrotoxicity was observed among controls and treated groups. These findings open perspectives to further explore this immunochemotherapeutic schedule as an alternative for treatment of visceral leishmaniasis.
Assuntos
Antiprotozoários , Leishmania infantum , Leishmaniose Visceral , Alopurinol/uso terapêutico , Animais , Antiprotozoários/uso terapêutico , Peso Corporal , Cricetinae , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/parasitologia , Mesocricetus , Fosforilcolina/uso terapêuticoRESUMO
INTRODUCTION: According to the "silica hypothesis" formulated to explain homeopathy, the information of starting materials would be transferred to cells by silica nanoparticles detached from the glassware walls by serial dilution and agitation through epitaxy. We compared the biological activity, electrical current and silicon microparticle content (by means of scanning electron microscopy/energy-dispersive X-ray spectroscopy) of high dilutions (HDs) of arsenic prepared in plastic and glass vials to investigate the role of silica in their biological effects in vitro. MATERIALS AND METHODS: Co-cultures of macrophages and yeast (Saccharomyces cerevisiae) were treated with different HDs of arsenic prepared in plastic and glass vials. Macrophage morphology, phagocytosis index, nitric oxide (NO), and cytokine production were evaluated. RESULTS: Measurable amounts of silicon microparticles were detected only in the HDs prepared in glass vials, but ultra-centrifugation eliminated them. Specific and non-specific results were observed. Non-specific pro-inflammatory effects were seen in all dilutions prepared in plastic vials, including elevation of pro-inflammatory cytokines, NO and macrophage phagocytic index. Only the 200th centesimal dilution of arsenic produced specific decrease in interleukin-6 production in macrophages, and it was independent of the vial type or the presence of microparticles of silica in the medicine samples. The nature of the vials had an impact on the electric flow in the respective fluids. CONCLUSION: The non-specific, pro-inflammatory effects might be attributed to organic residuals detached from the vials' plastic walls during manipulation. Instead, specific silica-independent effects of the homeopathic medicine can be attributed to the decrease of interleukin-6 after treatment with the 200th centesimal dilution of arsenic.
Assuntos
Arsenicais/isolamento & purificação , Condutividade Elétrica , Silício/isolamento & purificação , Citocinas/isolamento & purificação , Homeopatia/métodos , Humanos , Microscopia Eletrônica de Varredura/métodosRESUMO
Leishmaniasis is a term referring to a range of clinical conditions caused by protozoan parasites of the genus Leishmania, Trypanosomatidae family, Kinetoplastida order that is transmitted by the bite of certain species of mosquitoes Phlebotominae subfamily. These parasites infect hosts wild and domestic mammals, considered as natural reservoirs and can also infect humans. Leishmania are obligate intramacrophage protozoa that have exclusively intracellular life style. This suggests that the amastigotes possess mechanisms to avoid killing by host cells. Cutaneous leishmaniasis, the most common form of the disease, causes ulcers on exposed parts of the body, leading to disfigurement, permanent scars, and stigma and in some cases disability. Many studies concluded that the cytokines profile and immune system of host have fundamental role in humans and animals natural self-healing. Conventional treatments are far from ideals and the search for new therapeutic alternatives is considered a strategic priority line of research by the World Health Organization. A promising approach in the field of basic research in homeopathy is the treatment of experimental infections with homeopathic drugs prepared from natural substances associations highly diluted, which comprise a combination of several different compounds considered as useful for a symptom or disease. Therefore, this study aimed to evaluate the effect of M1, a complex homeopathic product, in macrophage-Leishmania interaction in vitro and in vivo. It was used RAW cells lineage and BALB/c mice as a host for the promastigotes of L. amazonensis (WHOM/BR/75/Josefa). Several biochemical and morphological parameters were determined. Together, the harmonic results obtained in this study indicate that, in general, the highly diluted products trigger rapid and effective responses by living organisms, cells and mice, against Leishmania, by altering cytokines profile, by NO increasing (p<0.05), by decreasing parasitic load (p<0.001), and modifying classical maturation and biogenesis of parasitophorous vacuoles (p<0.001). M1 complex decreased endocytic index (p<0.001), and the % of infected macrophages (p<0.05), preventing the development of lesions (p<0.05) caused by L. amazonensis by increasing Th1 response (p<0.05). Therefore the M1complex can be a good candidate for a complementary therapy to conventional treatments, since all the parameters observed in vitro and in vivo improved. It could be an interesting clinical tool in association to a classical anti-parasitic treatment, maybe resulting in better quality of life to the patients, with less toxicity.
Assuntos
Homeopatia , Leishmania/fisiologia , Animais , Bioensaio , Citocinas/metabolismo , Peróxido de Hidrogênio/metabolismo , Leishmania/ultraestrutura , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/patologia , Macrófagos/parasitologia , Macrófagos/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/metabolismo , Carga Parasitária , Células RAW 264.7RESUMO
BACKGROUND: In previous results mice treated with high dilutions of antimony presented reduction of monocyte migration to the site of infection with increase in B lymphocytes population in the local lymph node. AIMS: To know the mechanisms involved, a series of in vitro studies was done, using co-cultures of macrophages (RAW 264.7) and Leishmania (L.) amazonensis treated with different dilutions of antimony (Antimonium crudum or AC), in different times. METHODOLOGY: Spreading, phagocytosis, the oxidative activity of macrophages, the viability of free promastigotes and the cytokines/chemokines concentration in the supernatant were evaluated. The assays were performed in quadruplicate. RESULTS: Cells treated with AC 30cH (10-58M) and AC 200cH (10-398M) presented a temporary reduction of the spreading after 02h of incubation, followed by increase after 48h, being the most significant increase observed after the AC 200cH treatment. However, the percentage of internalized parasites at 48, 96 and 120h of incubation was also higher in cells treated with AC 200cH. It is suggested that the AC 200cH improves the ability of phagocytes to internalize the parasites, but not to digest them. The cytokines-chemokines panel corroborated these results. Both dilutions potentiated the parasite-induced reduction of cytokines production, especially IL-6, IL 12 p40 and γ-IFN, after 48h of incubation. In addition, the production of MIP-1 beta (CCL4), a chemokine involved in chronic inflammation, was also reduced after 120h. A specific effect of AC 30cH was seen by the inhibition of two peaks of CCL2 (MCP-1) observed in infected macrophages, at 24 and 120h. Since this cytokine is an important chemokine for monocytes, it explains the results obtained formerly in vivo. The morphology of macrophages after acridine orange staining revealed that the treatment with AC 30cH reduced substantially the acid vacuoles in the cytoplasm, indicating a certain inability of these cells to digest the parasites. On the other hand, a large peak of VEGF-A, associated with increase of internalized parasites was observed after 120h of treatment with AC 200cH, which could be associated to the regulation of the chronic inflammation events by M1-M2 polarization. There was no statistical difference among groups regarding the production of TNF, NO and H2O2, showing that the drugs do not alter macrophage cytotoxic activity. A clear quantitative and qualitative variation of the modulatory effects of AC 30cH and 200cH was seen, in function of time. CONCLUSIONS: Both dilutions were able to potentiate the decrease of most of cytokines and chemokines induced by the parasite infection in vitro, which explains the clinical improvement seen previously in vivo, however, the mechanisms involved and the epidemiological significance of these findings are still under discussion.
Assuntos
Antimônio/farmacologia , Leishmania/imunologia , Leishmaniose/imunologia , Macrófagos/imunologia , Monocinas/imunologia , Animais , Leishmaniose/patologia , Macrófagos/parasitologia , Camundongos , Células RAW 264.7RESUMO
Chagas' disease is a parasitosis caused by Trypanosoma cruzi, which affects approximately 8 million people worldwide. The balance between pro- and anti-inflammatory cytokines produced during immunological responses contributes to disease prognosis and progression. Parasite tissue persistence can induce chronic inflammatory stimuli, which can cause long-term tissue injury and fibrosis. Chronic Chagas' patients exhibit increased levels of interleukin (IL)-9, an important cytokine in the regulation of inflammatory and fibrogenic processes. Data on the role of IL-9 in other pathologies are sometimes contradictory, and few studies have explored this cytokine's influence in Chagas' disease pathology. Hence, the aim of this study was to evaluate the role of IL-9 in the progression of T. cruzi infection in vivo and in vitro. In vitro infection demonstrated that IL-9 reduced the number of infected cells and decreased the multiplication of intracellular amastigotes in both C2C12 myoblasts and bone marrow-derived macrophages. In myoblasts, the increased production of nitric oxide (NO) was essential for reduced parasite multiplication, whereas macrophage responses resulted in increased IL-6 and reduced TGF-ß levels, indicating that parasite growth restriction mechanisms induced by IL-9 were cell-type specific. Experimental infection of BALB/c mice with T. cruzi trypomastigotes of the Y strain implicated a major role of IL-9 during the chronic phase, as increased Th9 and Tc9 cells were detected among splenocytes; higher levels of IL-9 in these cell populations and increased cardiac IL-9 levels were detected compared to those of uninfected mice. Moreover, rIL9 treatment decreased serum IL-12, IL-6, and IL-10 levels and cardiac TNF-α levels, possibly attempting to control the inflammatory response. IL-9 neutralization increased cardiac fibrosis, synthesis of collagens I and III, and mastocyte recruitment in BALB/c heart tissue during the chronic phase. In conclusion, our data showed that IL-9 reduced the invasion and multiplication of T. cruzi in vitro, in both myoblasts and macrophages, favoring disease control through cell-specific mechanisms. In vivo, IL-9 was elevated during experimental chronic infection in BALB/c mice, and this cytokine played a protective role in the immunopathological response during this phase by controlling cardiac fibrosis and proinflammatory cytokine production.
Assuntos
Doença de Chagas , Interleucina-9 , Trypanosoma cruzi , Animais , Citocinas , Humanos , Camundongos , Camundongos Endogâmicos BALB CRESUMO
The present study analyzed the immune modulation mechanisms of thymulin 5CH in a granuloma experimental model. Male adult Balb/c mice were inoculated with BCG into the footpad to induce granuloma, which was quantitatively evaluated. The phenotypic characterization of phagocyte, T- and B-lymphocyte populations in the peritoneum, and local lymph node was done by flow cytometry. During all experimental periods, thymulin 5CH and vehicle (control) were given ad libitum to mice, diluted into the drinking water (1.6 × 10(-17) M). After 7 days from inoculation, thymulin-treated mice presented reduction in the number of epithelioid cytokeratine-positive cells (P = 0.0001) in the lesion, in relation to young phagocytes. After 21 days, the differentiation of B1 peritoneal stem cells into phagocytes reached the peak, being higher in thymulin-treated mice (P = 0.0001). Simultaneously, the score of infected phagocytes in the lesion decreased (P = 0.001), and the number of B1-derived phagocytes, CD4+ and CD8+ T lymphocytes in the local lymph node increased in relation to control (P = 0.0001). No difference was seen on the CD25+ Treg cells. The results show that thymulin 5CH treatment is able to improve the granuloma inflammatory process and the infection remission, by modulating local and systemic phagocyte differentiation.