LEISHMANICIDAL ACTIVITY in vivo OF A MILTEFOSINE DERIVATIVE IN Mesocricetus auratus.

Visceral leishmaniasis (VL) is a chronic and systemic disease; if untreated, it can cause death in a large number of cases. The therapy is based on the use of antimonials, which have been used for over 50 years. However, cases of resistance have been reported in some countries. In this context, miltefosine (MIL) was introduced to treat antimonial unresponsive cases. Nonetheless, in recent years MIL unresponsive and relapse cases of VL have increasingly been reported. In the current study, the therapeutic potential of compound 5-(4-(3-methanesulfonatepropyl)-1H-1,2,3-triazol-1-yl)dodecyl methanesulfonate (C11), an MIL derivative, was assessed in an experimental VL hamster model. For this purpose, golden hamsters (Mesocricetus auratus) were infected with Leishmania (L.) infantum chagasi and treated daily for 10 days with C11 and MIL administered orally; in addition, Glucantime (GLU), peritoneal route, were administered at 15, 10, 50 mg/kg body weight/day, respectively. Twenty four hours after the end of treatment the animals were euthanatized; and the specimens were collected to evaluate the relative mRNA expression of cytokines IFN-γ, TNF-α, IL-17, TGF-ß, IL-4 and IL-10 in fragments of the spleen and liver; moreover, the parasitism in these organs was evaluated as well as the main histopathological alterations. The C11-treated animals showed greater expression of IL-17 and TNF-α cytokines and reduced expression of IL-10 in the spleen in comparison to the infected untreated group (UTG) (p <0.05). The C11 and GLU groups showed a significant reduction in the IgG levels in comparison to the UTG group (p <0.05). Moreover, the C11-treated animals had fewer parasites in the spleen than the UTG animals (reduction of 95.9%), as well as a greater preservation of white pulp architecture in the spleen than the UTG, GLU and MIL groups (p <0.05). For the liver, the animals from the C11 and MIL groups showed a significant increase in TNF-α relative expression in comparison to the UTG animals, which would explain the increase in the number of granulomas and the reduction in the parasitic load (p <0.05). Combined, these findings indicate that C11 is an interesting compound that should be considered for the development of new drugs against VL, mainly due to its leishmanicidal effect and immunostimulating action.

Different DNA methylation profile is demonstrated in paracoccidioidomycosis patients without oral lesions.

BACKGROUND: Paracoccidioidomycosis (PCM) is a neglected fungal infection with a high impact on the quality of life of the affected patients. The disease presents primary pulmonary involvement and systemic dissemination may occur. About 50% of the cases show oral involvement, and the factors that lead to this manifestation are not clear. OBJECTIVES: The aim of this study was to evaluate the DNA methylation profile in PCM patients with oral lesions. MATERIAL AND METHODS: Genomic DNA was extracted from whole blood of eighteen PCM patients, being ten with oral lesions and eight with no oral lesion. Analysis of methylation profile was performed using the technique of methylation-sensitive arbitrarily primed PCR (MS-AP-PCR). The sequences of recombinant plasmids obtained were evaluated according to parameters that define a CpG island, as well as their relative position in the known human genome genes and/or CpG islands. RESULTS: After DNA amplification, three different expressed bands were observed between the two groups, being found in the samples of patients with no oral manifestations. The cloned fragment in the plasmid showed similarity with a DNA sequence present in chromosome 20, next to the YTHDF1 gene. Other bands showed homology with intronic region in the genes RBPMS2 and DPH6 and no CpG island was identified. CONCLUSIONS: DNA methylation was found in PCM patients with no oral lesion affecting the YTHDF1 gene. Further studies are necessary to elucidate to role of YTHDF1 gene in the oral PCM manifestations.

Low-level laser therapy to the mouse femur enhances the fungicidal response of neutrophils against Paracoccidioides brasiliensis.

Neutrophils (PMN) play a central role in host defense against the neglected fungal infection paracoccidioidomycosis (PCM), which is caused by the dimorphic fungus Paracoccidioides brasiliensis (Pb). PCM is of major importance, especially in Latin America, and its treatment relies on the use of antifungal drugs. However, the course of treatment is lengthy, leading to side effects and even development of fungal resistance. The goal of the study was to use low-level laser therapy (LLLT) to stimulate PMN to fight Pb in vivo. Swiss mice with subcutaneous air pouches were inoculated with a virulent strain of Pb or fungal cell wall components (Zymosan), and then received LLLT (780 nm; 50 mW; 12.5 J/cm2; 30 seconds per point, giving a total energy of 0.5 J per point) on alternate days at two points on each hind leg. The aim was to reach the bone marrow in the femur with light. Non-irradiated animals were used as controls. The number and viability of the PMN that migrated to the inoculation site was assessed, as well as their ability to synthesize proteins, produce reactive oxygen species (ROS) and their fungicidal activity. The highly pure PMN populations obtained after 10 days of infection were also subsequently cultured in the presence of Pb for trials of protein production, evaluation of mitochondrial activity, ROS production and quantification of viable fungi growth. PMN from mice that received LLLT were more active metabolically, had higher fungicidal activity against Pb in vivo and also in vitro. The kinetics of neutrophil protein production also correlated with a more activated state. LLLT may be a safe and non-invasive approach to deal with PCM infection.

Synthesis and Biological Evaluation of New Eugenol Mannich Bases as Promising Antifungal Agents.

New Mannich base-type eugenol derivatives were synthesized and evaluated for their anticandidal activity using a broth microdilution assay. Among the synthesized compounds, 4-allyl-2-methoxy-6-(morpholin-4-ylmethyl) phenyl benzoate (7) and 4-{5-allyl-2-[(4-chlorobenzoyl)oxy]-3-methoxybenzyl}morpholin-4-ium chloride (8) were found to be the most effective antifungal compounds with low IC50 values, some of them well below those of reference drug fluconazole. The most significant IC50 values were those of 7 against C. glabrata (1.23 µm), C. albicans and C. krusei (both 0.63 µm). Additionally, the synthesized compounds were evaluated for their in vitro cytotoxic effects on human mononuclear cells. As result, the cytotoxic activity of eugenol in eukaryotic cells decreased with the introduction of the morpholinyl group. Given these findings, we point out compounds 7 and 8 as the most promising derivatives because they showed potency values greater than those of eugenol and fluconazole and they also presented high selectivity indexes.

Biological evaluation of a nutritional supplement prepared with QPM Maize cultivar BR 473 and other traditional food items

Milho de Qualidade Protéica (QPM) da cultivar BR 473, desenvolvida pela EMBRAPA está sendo empregado, juntamente com farinha de soja, açúcar mascavo, farinha de banana e farinha de aveia, na preparação de um suplemento nutricional, usado na recuperação de crianças desnutridas no município de Governador Valadares, MG. Reporta-se aqui o resultado da avaliação biológica deste suplemento. Ratos Fisher machos de 21 dias de idade foram alimentados com dietas contendo o suplemento como fonte de proteína, com ou sem farinha de soja; dietas de caseína com 10 ou 7% de proteína serviram como respectivos controles. Foram determinadas a Razão de Eficiência Protéica (REP), a Utilização Líquida de Proteína (ULP), a Razão Líquida de Proteína (RLP) e a Digestibilidade. Parâmetros bioquímicos sanguíneos (glicose, colesterol, uréia, hemoglobina, albumina, e proteína total) foram também medidos nos animais e mostraram que todos estavam em boas condições de saúde ao final do experimento. Os resultados obtidos para REP, ULP, RLP e Digestibilidade indicam que o suplemento preparado com o milho QPM cultivar 473 é uma boa fonte de proteína, especialmente quando a farinha de soja é adicionada.