CNS & Neurological Disorders - Drug Targets (Formerly Current Drug Targets - CNS & Neurological Disorders) - Volume 19, Issue 6, 2020

Alzheimer Disease (AD) is the most prevalent type of dementia. Pathological changes in the AD brain include Amyloid β-protein (Aβ) plaques and Neurofibrillary Tangles (NFTs), as well as extensive neuronal and synaptic loss. Matrix Metalloproteinase-2 (MMP-2) is a neutral, zinc-dependent protease that primarily targets extracellular matrix proteins. MMP-2 activity is strictly controlled, and its dysregulation has been implicated in a variety of pathologies, including AD. In this brief review, we discussed the contributions of dysregulated MMP-2 activity and an imbalanced interaction between MMP-2 and its endogenous inhibitor, Tissue Inhibitors of Metalloproteinase-2 (TIMP-2), to AD. We also described the underlying mechanisms of the effects of MMP-2/TIMP-2, both beneficial and detrimental, on AD, including: (1) MMP-2 directly degrades Aβ resulting in the clearance of Aβ deposits. Conversely, Aβ-induced MMP-2 may contribute to brain parenchymal destruction. (2) MMP-2 induces breakdown of BBB, and this deleterious effect could be reversed by TIMP-2. (3) MMP-2 disrupts oxidative homeostasis in AD. (4) MMP-2 has both proinflammatory/pro-angiogenetic and antiinflammatory/ anti-angiogenetic effects on AD. Besides, we discuss the clinical utility of MMP- 2/TIMP-2 as therapeutic targets for AD.

Over the past few years, experimental research has been carried out to analyze the role of specific receptors in depression to better understand the mechanisms and pathophysiological aspects of the disease. In this paper, we aim to investigate the receptors family most involved in depression, as well as the tissues in which most depression related-receptors are expressed. The article also aims to identify the functions of the main receptors predominantly associated with the pathology. This review used a systematic methodology (Prospero; ID 168584) and followed the PRISMA guidelines. Studies were searched in PubMed/MEDLINE, Scientific Electronic Library Online, Web of Science, and Directory of Open Access Journals databases. Quantitative studies with conclusive results regarding receptors involved in depression were selected. The charts and network were made using R programming language and statistical analyses were carried out using SPSS v25 software. It can be seen that G protein-coupled receptors family is the most studied (p < 0.05). These receptors are expressed in the cerebral cortex, basal ganglia, and can interact with each other. A great number of studies have evaluated receptors related to beneficial effects in the disease (p < 0.05). The inflammation response and cell survival/proliferation are the main functions related to these receptors (p < 0.01) and behavioral tests in mice are the main methodologies applied in these studies (p < 0.05). Finally, the most influential protein on the network of receptors involved in depression is the Bradykinin receptor B1. G protein- coupled receptors located in cell membranes involving especially protective effects in depression and that expressed mainly in the cerebral cortex and basal ganglia have shown significant importance in this review. In addition, inflammation response or cell survival/proliferation are the main functions performed by the receptors related to depression as observed in this work.

Background: ALDH-2 has been considered an important molecular target for the treatment of drug addiction due to its involvement in the metabolism of the neurotransmitter dopamine: however, the molecular basis for the selective inhibition of ALDH-2 versus ALDH-1 should be better investigated to enable a more pragmatic approach to the design of novel ALDH-2 selective inhibitors. Objective: In the present study, we investigated the molecular basis for the selective inhibition of ALDH-2 by the antioxidant isoflavonoid daidzin (IC50 = 0.15 μM) compared to isoform 1 of ALDH through molecular dynamics studies and semiempirical calculations of the enthalpy of interaction. Methods: The applied methodology consisted of performing the molecular docking of daidzin in the structures of ALDH-1 and ALDH-2 and submitting the lower energy complexes obtained to semiempirical calculations and dynamic molecular simulations. Results: Daidzin in complex with ALDH-2 presented directed and more specific interactions, resulting in stronger bonds in energetic terms and, therefore, in enthalpic gain. Moreover, the hydrophobic subunits of daidzin, in a conformationally more restricted environment (such as the catalytic site of ALDH-2), promote the better organization of the water molecules when immersed in the solvent, also resulting in an entropic gain. Conclusion: The molecular basis of selective inhibition of ALDH-2 by isoflavonoids and related compounds could be related to a more favorable equilibrium relationship between enthalpic and entropic features. The results described herein expand the available knowledge regarding the physiopathological and therapeutic mechanisms associated with drug addiction.

Background: Anxiety and oxidative stress are the common disorders prevailing in the modern age. Many new pyrazoline derivatives have been synthesized and patented, but there is still continuous research in progress to explore antidepressant and antioxidant potential of pyrazoline scaffold. Objectives: The present work was carried out to synthesize, characterize and evaluate the pharmacological potential of 1,3,5-Pyrazoline derivatives. Methods: Ten new 1,3,5-Pyrazoline derivatives were synthesized and characterized by IR, 1HNMR and mass spectral techniques. The synthesized pyrazoline derivatives were investigated for their in vivo antidepressant activity by Tail Suspension Test (TST) and in vitro antioxidant activity by FRAP and DPPH assay methods. The docking studies and in silico ADME and toxicity characteristics were also evaluated. Results: Among the synthesized analogues, IVh showed the highest antidepressant activity with a significant reduction in the duration of immobility. The compound IVh emerged as the most potent antioxidant compound due to the presence of an electron releasing hydroxyl group. Docking studies of most potent compounds revealed good interaction points with the MAO-A enzyme. The compounds were found to obey Lipinski’s Rule of Five and displayed the least in silico toxicity profile. Conclusion: The synthesized compounds were found to possess great potential in decreasing the duration of immobility in Swiss albino mice and scavenging free radicals. These compounds may serve as new leads for further drug exploration.

Objective: The aim of this paper is to demonstrate the impact of hemodialysis (HD) using synthetic Helixone membrane on brain functional control reorganization and plasticity in the cortical area generated while Oxidative Stress (OS) would be the main impacting agent. Methods: Indeed, 9 chronic HD patients underwent identical brain BOLD-fMRI assessment using the motor paradigm immediately before and after the same HD sessions. To assess the oxidative stress, the same patients underwent biological-assessment, including Malondialdehyde (MDA) and Total- Antioxidant-Activity (TAOA) reported in earlier papers. Results: BOLD-fMRI maps of motor areas obtained from HD-patients before and after HD sessions revealed a significant enhancement of activation volume of the studied motor cortex after HD reflecting brain plasticity. Results were correlated with OS assessed by the measurement of MDA and TAOA; this correlation was close to 1. Conclusion: Indeed, HD enhances the inflammatory state of brain tissues reflected by the increased OS. The functional brain reaction demonstrated a functional activity reorganization to overcome the inflammatory state and OS enhanced by HD process. This functional activity reorganization reveals brain plasticity induced by OS originated by HD.