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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.

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ETHNOPHARMACOLOGICAL RELEVANCE: Vernonia scorpioides (Asteraceae) is a native Brazilian medicinal plant that is commonly used to treat skin disorders. Considering the traditional use of Vernonia scorpioides and the lack of information about its pharmacological properties, we investigated the topical anti-inflammatory effect of the ethanolic extract of Vernonia scorpioides (EEVS) on acute and chronic cutaneous inflammation models in mouse. MATERIALS AND METHODS: The topical anti-inflammatory effect of EEVS was evaluated against acute models (12-O-tetradecanoylphorbol acetate (TPA)- and arachidonic acid (AA)-induced mouse ear oedema) and chronic models (multiple applications of croton oil). RESULTS: The EEVS caused a dose-related inhibition of oedema in both the TPA- and AA-induced acute models (DI(50)=0.24 and 0.68 mg/ear with an inhibition of 80 ± 5% and 65 ± 5%, respectively, for 1mg/ear). In addition, the TPA-induced increase in myeloperoxidase activity (MPO) in the ear was reduced (77 ± 8%) by the topical application of EEVS. In the chronic model, the EEVS reduced all parameters evaluated: oedema formation (31 ± 2%), epidermal hyperproliferation (histology) and MPO (25 ± 10%). However, the topical treatment of EEVS had no effect on N-acetyl-ß-d-glucosaminidase activity. The EEVS effectively interfered in the ear oedema on the delayed-type hypersensitivity reaction induced by oxazolone. The topical treatment with EEVS performed on both phases or only on the elicitation phase caused the inhibition of the ear oedema-induced by oxazolone in 42.9% and 63.4%, respectively, when compared to control animals (sensitized and challenged). CONCLUSIONS: The results suggest that EEVS is effective as a topical anti-inflammatory agent in acute and chronic inflammatory processes and that its action is markedly influenced by the inhibition of neutrophil migration into inflamed tissue as well as by epidermal hyperproliferation.

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BACKGROUND: Melanoma is the most aggressive form of skin cancer and the most rapidly expanding cancer in terms of worldwide incidence. Chemotherapeutic approaches to treat melanoma have had only marginal success. Previous studies in mice demonstrated that a high diluted complex derived from Calcarea carbonica (M8) stimulated the tumoricidal response of activated lymphocytes against B16F10 melanoma cells in vitro. METHODS: Here we describe the in vitro inhibition of invasion and the in vivo anti-metastatic potential after M8 treatment by inhalation in the B16F10 lung metastasis model. RESULTS: We found that M8 has at least two functions, acting as both an inhibitor of cancer cell adhesion and invasion and as a perlecan expression antagonist, which are strongly correlated with several metastatic, angiogenic and invasive factors in melanoma tumors. CONCLUSION: The findings suggest that this medication is a promising non-toxic therapy candidate by improving the immune response against tumor cells or even induce direct dormancy in malignancies.

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BACKGROUND: Melanoma is the most aggressive form of skin cancer, and the most rapidly expanding cancer in terms of worldwide incidence. Chemotherapeutic approaches to treat melanoma have been uniformly disappointing. A Brazilian complex homeopathic medication (CHM), used as an immune modulator, has been recommended for patients with depressed immune systems. Previous studies in mice have demonstrated that the CHM activates macrophages, induces an increase in the number of leukocytes and improves the murine response against Sarcoma-180. METHODS: Here we studied the interaction of mouse lymph node lymphocytes, co-cultured in vitro with macrophages in the presence or absence of the CHM, with B16F10 melanoma cells. RESULTS: Lymphocytes co-cultured with macrophages in the presence of the CHM had greater anti-melanoma activity, reducing melanoma cell density and increasing the number of lysed tumor cells. There was also a higher proportion of activated (CD25+) lymphocytes with increased viability. Overall, lymphocytes activated by treatment destroyed growing cancer cells more effectively than control lymphocytes. CONCLUSION: Co-culture of macrophages with lymphocytes in the presence of the CHM enhanced the anti-cancer performance of lymphocytes against a very aggressive lineage of melanoma cells. These results suggest that non-toxic therapies using CHMs are a promising alternative approach to the treatment of melanomas. In addition, they are attractive combination-therapy candidates, which may enhance the efficacy of conventional medicines by improving the immune response against tumor cells.

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Some ultrastructural and cytochemical aspects of Lepista sordida are described. Basidiospores with verruculose and irregular ornamentations were observed through scanning electron microscopy. Confocal microscopy indicated that most of them exhibited a single large lipid body, no acidic vesicles and nucleus localized in the cell periphery.

Este trabalho descreve aspectos ultraestruturais e citoquímicos de Lepista sordida. Basidiósporos recobertos com ornamentações verruculosas e irregulares foram observados através de microscopia eletrônica de varredura. Através de microscopia confocal verificou-se que a maioria apresentava um grande corpo lipídico, ausência de vesículas ácidas e núcleo localizado na periferia.

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A structural study of the carbohydrates from Trebouxia sp., the algal symbiont of the lichen Ramalina gracilis demonstrated a galactofuranan-rich heteropolysaccharide, which was predominated by (1-->5)-linked galactofuranosyl units with side-chains in position 6 on approximately 11.0% of the units. The side-chains have very complex branched structures. This polysaccharide showed cell eliciting activity on peritoneal macrophages in vitro at all concentrations tested (1-150 microg/mL), and at 150 microg/mL an increase of 60% of macrophage activation in comparison to the control group was observed. A potential role of these carbohydrates in lichen recognition process is also discussed.

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Some ultrastructural and cytochemical aspects of Lepista sordida are described. Basidiospores with verruculose and irregular ornamentations were observed through scanning electron microscopy. Confocal microscopy indicated that most of them exhibited a single large lipid body, no acidic vesicles and nucleus localized in the cell periphery.

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The total carbohydrate content of the intact pulp of Spondias cytherea was 41%. Polysaccharides were obtained via hot aqueous extraction after defatting with organic solvents. The aqueous extract was treated with excess ethanol to form a precipitate, which was then solubilized in water. The material precipitated upon acidification when HCl was removed. The resulting supernatant fraction was submitted to freeze-thawing treatment yielding a soluble fraction (sFTS). This fraction had Ara, Rha, Gal and GalA in its structure as determined by GC-MS. 13C NMR analysis showed signals assigned to alpha-L-Araf, beta-D-Galp, alpha-D-GalpA and alpha-L-Rhap units, in addition to galacturonic acid units, which were present also as methyl ester. These results suggest a type I rhamnogalacturonan with arabinogalactan branches. Cell eliciting activity in a dose-depending pattern was observed in vitro on peritoneal macrophages treated with sFTS.

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Brazilian flora are a source of interesting polysaccharides which, either in their native state or when submitted to structural modifications, might have potential applications as biological response modifiers (BRM). A complex acidic heteropolysaccharide, containing mainly galactose and arabinose (ARAGAL), isolated from the gum of the native leguminous tree Anadenanthera colubrina (Angico branco), was studied for its immunological properties on peritoneal exudate cells, namely their superoxide anion production, phagocytic activity, morphological alterations and percentage content of activated macrophages. Activation of macrophages showing increased cytoplasm, bright and large nuclei, various cytoplasmatic projections and spreading ability, was detected following in vitro cell exposure to ARAGAL or in cells obtained from treated animals. In vitro exposure to ARAGAL increased the occurrence of activated macrophages in a time- and a dose-dependent pattern, since approximately 82% of the cells were activated in the presence of 300 microg/ml of ARAGAL after 24 h of incubation and approximately 91% after 48 h. The occurrence of activated macrophages was also evident in cell preparations from ARAGAL-treated mice, their percentage showing a dose-dependent pattern. There were approximately 60, 75 and 75% following treatment with 100, 250 and 500 mg/kg of ARAGAL, respectively. A phagocytic assay showed that 25 microg/ml ARAGAL was sufficient to impose a maximum phagocytic ability, although this effect was dose-dependent. O(2)(-) production by macrophages from ARAGAL-treated mice was 70% higher than that of cells from untreated mice. Moreover, cells from treated mice responded to PMA, the effect being 25% higher than that of the control using untreated mice. These results thus suggest a possible role of ARAGAL from A. colubrina as a BRM.

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