Ruben Dario Sinisterra Millan

Proteomic white adipose tissue analysis of obese mice fed with a high-fat diet and treated with oral angiotensin-(1–7)

Angiotensin-(1-7) has been described as a new potential therapeutic tool for the treatment and prevention of metabolic disorders by regulating several pathways in visceral white adipose tissue (vWAT). The aim of this study was to access the proteins differentially regulated by Ang-(1-7) using proteomic analysis of visceral adipose tissue. Male mice were divided into three groups and fed for 60 days, with each group receiving one of the following diets: standard diet+HPβCD (ST), high fat diet+HPβCD (HFD) and high fat diet+Ang-(1-7)/HPβCD (HFD+Ang-(1-7)). Body weight, fat weight and food intake were measured. At the end of treatment, Ang-(1-7) induced a decrease in body and fat weight. Differential proteomic analysis using two-dimensional electrophoresis (2-DE) combined with mass spectrometry were performed. Results of protein mapping of mesenteric adipose tissue using 2-DE revealed the presence of about 450 spots in each gel (n=3/treatment) with great reproducibility (>70%). Image analysis and further statistical analysis allowed the detection and identification of eight proteins whose expression was modulated in response to HFD when compared to ST. Among these, two proteins showed a sensitive response to Ang-(1-7) treatment (eno1 and aldehyde dehydrogenase). In addition, three proteins were expressed statistically different between HFD+Ang-(1-7) and HFD groups, and four proteins were modulated compared to standard diet. In conclusion, comparative proteomic analysis of a mice model of diet-induced obesity allowed us to outline possible pathways involved in the response to Ang-(1-7), suggesting that Ang-(1-7) may be a useful tool for the treatment of metabolic disorders.

Chemical composition and antifungal and anticancer activities of extracts and essential oils of Schinus terebinthifolius Raddi fruit

In this study, we isolated and characterized dichloromethane and hexane extracts, complexed with hydroxypropyl-β-cyclodextrin (HP-β-CD), of Schinus terebinthifolius fruits. Such complexation may be useful in the formulation of herbal medicines, by improving solubility, or increasing stability by reducing the loss of volatile compounds. The cytotoxicity in osteoblasts, antifungal against Malassezia furfur and antitumor activities were evaluated in Caco-2 cells. The antifungal activity of the extracts and the essential oil in natura or complexed with HP-β-CD against the fungus M. furfur was evaluated by agar diffusion methods and quantitatively by inhibitory concentration (IC). All samples inhibited fungus growth and, when complexed with HP-β-CD, the IC was reduced by 50%. Osteoblast cell viability was not affected by the presence of extracts and oil. The antitumor activity of the extract in dichloromethane was evaluated using Caco-2 cells. The results demonstrated significant reduction in cell viability in the presence of the extract, which makes it a promising candidate for cancer treatment.

Caracterização físico-química de complexos de insulina: dimetil-beta-ciclodextrina e insulina: hidroxipropil-beta-ciclodextrina e avaliação da influência do tipo de complexo na produção de microesferas biodegradáveis

The main stage in the linking and activation of the specific receptors by the insulin is the dissociation of this peptide hexamers, normally present in pharmaceutical formulations, in the monomeric active form. Because of this, the use of different cyclodextrins as adjuvants in the formulations containing insulin has been explored and the realized studies have demonstrated that the cyclodextrins can increase the absorption of the insulin mainly by reducing the ability of insulin oligomerization in aqueous media. In this work, complexes of INS:HP-b-CD and INS:DM-b-CD have been characterized by the use of isothermal calorimetry titration (ICT) and dynamic scattering of light. By means of ICT, the thermodynamic parameters of interaction between insulin and the cyclodextrins have been determined, and it was observed that the complexation occurs with an increase of entropy for both systems. The experiments of dynamic scattering of light have not showed reduction in the size of insulin particles, which could indicate the dissociation of insulin hexamers after the complexation with cyclodextrins. Then, the INS: HP-b-CD and INS:DM-b-CD complexes were encapsulated in PLGA microspheres. These systems were characterized and it was not observed any significant difference in the microspheres diameter, but a considerable increase in the hormone loading after the complexation with HP-b-CD and DM-b-CD was shown.