Selenium-Derivative Compounds: A Review of New Perspectives in the Treatment of Alzheimer's Disease.

BACKGROUND: Alzheimer's disease (AD) is one of the most prevalent types of dementia, affecting millions of older people worldwide. AD is stimulating efforts to develop novel molecules targeting its main features associated with a decrease in acetylcholine levels, an increase in oxidative stress and depositions of amyloid-ß (Aß) and tau protein. In this regard, selenium-containing compounds have been demonstrated as potential multi-targeted compounds in the treatment of AD. These compounds are known for their antioxidant and anticholinesterase properties, causing a decrease in Aß aggregation. OBJECTIVE: In this review, we approach structure-activity relationships of each compound, associating the decrease of ROS activity, an increase of tau-like activity and inhibition of AChE with a decrease in the self-aggregation of Aß. METHODS: We also verify that the molecular descriptors apol, nHBAcc and MlogP may be related to optimized pharmacokinetic properties for anti-AD drugs. RESULTS: In our analysis, few selenium-derived compounds presented similar molecular features to FDA-approved drugs. CONCLUSION: We suggest that unknown selenium-derived molecules with apol, nHBAcc and MlogP like FDA-approved drugs may be better successes with optimized pharmacokinetic properties in future studies in AD.

Pyrazolines as potential anti-Alzheimer's agents: DFT, molecular docking, enzyme inhibition and pharmacokinetic studies.

Alzheimer's disease (AD) is a neurodegenerative disease that is characterized as the main dementia in the elderly. Eighteen pyrazolines were synthesized and evaluated for their inhibitory effects against acetylcholinesterase (AChE) in vitro. Possible interactions between pyrazolines and the enzyme were explored by in silico experiments. Compound 2B of the series was the most active pyrazoline with an IC50 value of 58 nM. Molecular docking studies revealed two important π-π interactions with residues Trp 286 and Tyr 341. A correlation between the HOMO-1 surface and AChE inhibition was observed. ADMET assays demonstrated a good profile for compound 2B. From the abovementioned findings, a new avenue of compound 2B analogues could be explored to develop anti-AD agents.

Synthesis and investigation of the trypanocidal potential of novel 1,2,3-triazole-selenide hybrids.

Chagas Disease is caused by the protozoan Trypanosoma cruzi and is considered a tropical neglected disease by the World Health Organization (WHO). The main drugs used in the therapy of the disease are obsolete and, as a result, it still kills millions of people every year. Therefore, the development of new drugs is urgent, as is the research reported in this article, in which new triazole selenides were synthesized through a simple methodology and to evaluate their potential against T. cruzi, through a combination of in vitro and in silico assays. With the combination of two molecular scaffolds already known for this activity, sixteen new hybrid compounds were obtained, showing yields ranging from 40 to 90%, and their biological potentials were tested. Two of the evaluated hybrids showed potent trypanocidal activity (11m and 11n), comparable to the positive control benznidazole. Density functional theory (DFT) studies were correlated with cyclic voltammetry assays to investigate the LUMO energy, which demonstrated a correlation with the observed trypanocidal activity. These results are promising, considering 11m and 11n as hit compounds in the development of new antichagasic drugs.

Carajurin: a anthocyanidin from Arrabidaea chica as a potential biological marker of antileishmanial activity.

Leishmaniasis is a group of neglected tropical diseases whose treatment with antimonials bears limitations and has changed little in over 80 years. Medicinal plants have been evaluated as a therapeutic alternative for leishmaniasis. Arrabidaea chica is popularly used as a wound healing and antiparasitic agent, especially as leishmanicidal agent. This study examined the leishmanicidal activity of a crude extract (ACCE), an anthocyanidin-rich fraction (ACAF), and three isolated anthocyanidins from A. chica: carajurin, 3'-hydroxy-carajurone, and carajurone. We evaluated the antileishmanial activity against promastigote and intracellular amastigote forms of Leishmania amazonensis and determined cytotoxicity in BALB/c peritoneal macrophages, as well as nitrite quantification, using the Griess method. Molecular docking was carried out to evaluate interactions of carajurin at the nitric oxide synthase enzyme. All compounds were active against promastigotes after 72 h, with IC50 values of 101.5 ± 0.06 µg/mL for ACCE and 4.976 ± 1.09 µg/mL for ACAF. Anthocyanidins carajurin, 3'-hydroxy-carajurone, and carajurone had IC50 values of 3.66 ± 1.16, 22.70 ± 1.20, and 28.28 ± 0.07 µg/mL, respectively. The cytotoxicity assay after 72 h showed results ranging from 9.640 to 66.74 µg/mL for anthocyanidins. ACAF and carajurin showed selectivity against intracellular amastigote forms (SI> 10), with low cytotoxicity within 24 h, a statistically significant reduction in all infection parameters, and induced nitrite production. Molecular docking studies were developed to understand a possible mechanism of activation of the nitric oxide synthase enzyme, which leads to an increase in the production of nitric oxide observed in the other experiments reported. These results encourage us to suggest carajurin as a biological marker of A. chica.