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The brain has a unique biological complexity and is responsible for important functions in the human body, such as the command of cognitive and motor functions. Disruptive disorders that affect this organ, e.g. neurodegenerative diseases (NDDs), can lead to permanent damage, impairing the patients’ quality of life and even causing death. In spite of their clinical diversity, these NDDs share common characteristics, such as the accumulation of specific proteins in the cells, the compromise of the metal ion homeostasis in the brain, among others. Despite considerable advances in understanding the mechanisms of these diseases and advances in the development of treatments, these disorders remain uncured. Considering the diversity of mechanisms that act in NDDs, a wide range of compounds have been developed to act by different means. Thus, promising compounds with contrasting properties, such as chelating agents and metal-based drugs have been proposed to act on different molecular targets as well as to contribute to the same goal, which is the treatment of NDDs. This review seeks to discuss the different roles and recent developments of metal-based drugs, such as metal complexes and metal chelating agents as a proposal for the treatment of NDDs.

For many decades, synthetic receptors have been used as sensor elements and are a promising alternative to natural receptors, which, despite its great selectivity, are so complex and instable. The rational design of this kind of receptors is currently one of the most researched topics in molecular recognition. Molecular imprinted polymers (MIPs) have become a growing highlight in polymer chemistry, once they possess a wide range of applications and can be used in several environments, due to their high chemical and thermal stability. The aim of this study was to perform a rational design for the MIP preparation, for 3,4-methylenedioxymethamphetamine (MDMA) detection. The theoretical measurements were employed at several stages of the process, using DFT and B3LYP/6-31G(d,p) level of theory, by means of optimization and frequency calculations. Among the several functional monomers tested, the itaconic acid was the most appropriated for MIP preparation with MDMA template, and the proper molar ratio found theoretically was 3:1 (itaconic acid/MDMA). In the preparation of pre-polymerization complex, polar solvents were found to perform a better stabilization, mainly those which are not protic solvents. As cross-linking agents, the better results were obtained for trimethylolpropane trimethacrylate and ethylene glycol dimethacrylate molecules, respectively. Finally, selectivity tests showed a high affinity of the studied MIP for MDMA and chemically similar molecules. The proposal theoretical strategy yielded novel, experimentally testable hypotheses for the design of MIPs. Additionally, from the theoretical point of view, the set of computational analyses presented in this paper constitutes a very useful protocol to predict optimal experimental conditions, which can considerably reduce the time and cost on the MIPs preparation.

Human phospholipase A2 (hPLA2) of the IIA group (HGIIA) catalyzes the hydrolysis of membrane phospholipids, producing arachidonic acid and originating potent inflammatory mediators. Therefore, molecules that can inhibit this enzyme are a source of potential anti-inflammatory drugs, with different action mechanisms of known anti-inflammatory agents. For the study and development of new anti-inflammatory drugs with this action mechanism, snake venom PLA2 (svPLA2) can be employed, since the svPLA2 has high similarity with the human PLA2 HGIIA. Despite the high similarity between these secretory PLA2s, it is still not clear if these toxins can really be employed as an experimental model to predict the interactions that occur with the human PLA2 HGIIA and its inhibitors. Thus, the present study aims to compare and evaluate, by means of theoretical calculations, docking and molecular dynamics simulations, as well as experimental studies, the interactions of human PLA2 HGIIA and two svPLA2s, Bothrops toxin II and Crotoxin B (BthTX-II and CB, respectively). Our theoretical findings corroborate experimental data and point out that the human PLA2 HGIIA and svPLA2 BthTX-II lead to similar interactions with the studied compounds. From our results, the svPLA2 BthTX-II can be used as an experimental model for the development of anti-inflammatory drugs for therapy in humans.

The chemical compositions of the essential oils from the leaves and flowers of Callistemon viminalis and their insecticide and fungitoxic activities were determined. The essential oil was extracted by the hydrodistillation method using a modified Clevenger apparatus. The chemical characterization was performed by GC-MS and GC-FID. The evaluation of the insecticidal activity was performed with the Myzus persicae aphid, and the antifungal potential was determined via the inhibition of the mycelial growth of Alternaria alternata, Fusarium oxysorum and Botrytis cinérea phytopathogenic fungi. The principal components of the essential oils from the leaves and flowers were eucalyptol (84.60% and 61.47%), α-pinene (10.28% and 21.48%) and α-terpineol (2.59% and 2.79%), respectively. The use of a 0.5% concentration of the essential oil from the flowers influenced the preference of aphids and their reproduction. The number of adult aphids decreased within a period of 48 hours in the presence of the essential oil from the leaves. In the test with no chance of choice, the mean number of adults decreased with both oils within 48 hours.