Multitarget 2'-hydroxychalcones as potential drugs for the treatment of neurodegenerative disorders and their comorbidities

Neurodegeneration: can metabolites from Eremurus persicus help?

The number of patients affected by neurodegenerative diseases is increasing worldwide, and no effective treatments have been developed yet. Although precision medicine could represent a powerful tool, it remains a challenge due to the high variability among patients. To identify molecules acting with innovative mechanisms of action, we performed a computational investigation using SAFAN technology, focusing specifically on HuD. This target belongs to the human embryonic lethal abnormal visual-like (ELAV) proteins and plays a key role in neuronal plasticity and differentiation. The results highlighted that the molecule able to bind the selected target was (R)-aloesaponol-III-8-methyl ether [(R)-ASME], a metabolite extracted from Eremurus persicus. Notably, this molecule is a TNF-α inhibitor, a cytokine involved in neuroinflammation. To obtain a suitable amount of (R)-ASME to confirm its activity on HuD, we optimized the extraction procedure. Together with ASME, another related metabolite, germichrysone, was isolated. Both ASME and germichrysone underwent biological investigation, but only ASME confirmed its ability to bind HuD. Given the multifactorial nature of neurodegenerative diseases, we decided to investigate ASME as a proteasome activator, being molecules endowed with this kind of activity potentially able to counteract aggregations of dysregulated proteins. ASME was able to activate the considered target both in enzymatic and cellular assays. Therefore, ASME may be considered a promising hit in the fight against neurodegenerative diseases.

Active Compounds of Panax ginseng in the Improvement of Alzheimer's Disease and Application of Spatial Metabolomics

Panax ginseng C.A. Meyer (P. ginseng) is one of the more common traditional Chinese medicines (TCMs). It contains numerous chemical components and exhibits a range of pharmacological effects. An enormous burden is placed on people's health and life by Alzheimer's disease (AD), a neurodegenerative condition. Recent research has shown that P. ginseng's chemical constituents, particularly ginsenosides, have a significant beneficial impact on the prevention and management of neurological disorders. To understand the current status of research on P. ginseng to improve AD, this paper discusses the composition of P. ginseng, its mechanism of action, and its clinical application. The pathogenesis of AD includes amyloid beta protein (Aβ) generation and aggregation, tau protein hyperphosphorylation, oxidant stress, neuroinflammation, mitochondrial damage, and neurotransmitter and gut microbiota disorders. This review presents the key molecular mechanisms and signaling pathways of the active ingredients in P. ginseng involved in improving AD from the perspective of AD pathogenesis. A P. ginseng-related signaling pathway network was constructed to provide effective targets for the treatment of AD. In addition, the application of spatial metabolomics techniques in studying P. ginseng and AD is discussed. In summary, this paper discusses research perspectives for the study of P. ginseng in the treatment of AD, including a systematic and in-depth review of the mechanisms of action of the active substances in P. ginseng, and evaluates the feasibility of applying spatial metabolomics in the study of AD pathogenesis and pharmacological treatment.

Investigation of the Potential Targets behind the Promising and Highly Selective Antileishmanial Action of Synthetic Flavonoid Derivatives

Leishmaniases are among the neglected tropical diseases that still cause devastating health, social, and economic consequences to more than 350 million people worldwide. Despite efforts to combat these vector-borne diseases, their incidence does not decrease. Meanwhile, current antileishmanial drugs are old and highly toxic, and safer presentations are unaffordable to the most severely affected human populations. In a previous study by our research group, we synthesized 17 flavonoid derivatives that demonstrated impressive inhibition capacity against rCPB2.8, rCPB3, and rH84Y. These cysteine proteases are highly expressed in the amastigote stage, the target form of the parasite. However, although these compounds have been already described in the literature, until now, the amastigote effect of any of these molecules has not been proven. In this work, we aimed to deeply analyze the antileishmanial action of this set of synthetic flavonoid derivatives by correlating their ability to inhibit cysteine proteases with the action against the parasite. Among all the synthesized flavonoid derivatives, 11 of them showed high activity against amastigotes of Leishmania amazonensis, also providing safety to mammalian host cells. Furthermore, the high production of nitric oxide by infected cells treated with the most active cysteine protease B (CPB) inhibitors confirms a potential immunomodulatory response of macrophages. Besides, considering flavonoids as multitarget drugs, we also investigated other potential antileishmanial mechanisms. The most active compounds were selected to investigate another potential biological pathway behind their antileishmanial action using flow cytometry analysis. The results confirmed an oxidative stress after 48 h of treatment. These data represent an important step toward the validation of CPB as an antileishmanial target, as well as aiding in new drug discovery studies based on this protease.

Targeting GABA receptors with chalcone derivative compounds, what is the evidence?

INTRODUCTION

In medicinal chemistry, privileged structures have been frequently exploited as a successful template for drug discovery. Common simple scaffolds like chalcone are present in a wide range of naturally occurring chemicals. Chalcone exhibits extensive biological activity and has drawn attention in this context due to its function in the GABA receptor. Epilepsy and GABA receptors are related. It is a chronic neurological condition that affects globally.

AREAS COVERED

Numerous neurological disorders, including anxiety and epilepsy, have been related to GABA, the brain's most prevalent inhibitory neurotransmitter. We go through the role of GABA receptors in anxiety and epilepsy in this review. The structure-activity relationship of chalcone and its derivatives on the GABA receptor is covered in our final section.

EXPERT OPINION

GABA is a potential therapeutic target for issues associated with the nervous system. We talk about the potential effects of chalcone as a treatment for epilepsy and anxiety on the GABA receptor. Therefore, thorough research is necessary in this regard; the value of in silico tools in developing and enhancing GABA agonists is significant.

Flavonoid Derivatives as New Potent Inhibitors of Cysteine Proteases: An Important Step toward the Design of New Compounds for the Treatment of Leishmaniasis

Leishmaniasis is a neglected tropical disease, affecting more than 350 million people globally. However, there is currently no vaccine available against human leishmaniasis, and current treatment is hampered by high cost, side-effects, and painful administration routes. It has become a United Nations goal to end leishmaniasis epidemics by 2030, and multitarget drug strategy emerges as a promising alternative. Among the multitarget compounds, flavonoids are a renowned class of natural products, and a structurally diverse library can be prepared through organic synthesis, which can be tested for biological effectiveness. In this study, we synthesised 17 flavonoid analogues using a scalable, easy-to-reproduce, and inexpensive method. All synthesised compounds presented an impressive inhibition capacity against rCPB2.8, rCPB3, and rH84Y enzymes, which are highly expressed in the amastigote stage, the target form of the parasite. Compounds 3c, f12a, and f12b were found to be effective against all isoforms. Furthermore, their intermolecular interactions were also investigated through a molecular modelling study. These compounds were highly potent against the parasite and demonstrated low cytotoxic action against mammalian cells. These results are pioneering, representing an advance in the investigation of the mechanisms behind the antileishmanial action of flavonoid derivatives. Moreover, compounds have been shown to be promising leads for the design of other cysteine protease inhibitors for the treatment of leishmaniasis diseases.

Conjugated Dienones from Differently Substituted Cinnamaldehyde as Highly Potent Monoamine Oxidase-B Inhibitors: Synthesis, Biochemistry, and Computational Chemistry

Fifteen multiconjugated dienones (MK1-MK15) were synthesized and evaluated to determine their inhibitory activities against monoamine oxidases (MAOs) A and B. All derivatives were found to be potent and highly selective MAO-B inhibitors. Compound MK6, with an IC₅₀ value of 2.82 nM, most effectively inhibited MAO-B, like MK12 (IC₅₀ = 3.22 nM), followed by MK5, MK13, and MK14 (IC₅₀ = 4.02, 4.24, and 4.89 nM, respectively). The selectivity index values of MK6 and MK12 for MAO-B over MAO-A were 7361.5 and 1780.5, respectively. Compounds MK6 and MK12 were competitive reversible inhibitors of MAO-B, with K _i values of 1.10 ± 0.20 and 3.0 ± 0.27 nM, respectively. Cytotoxic studies showed that MK5, MK6, MK12, and MK14 exhibited low toxicities on Vero cells, with IC₅₀ values of 218.4, 149.1, 99.96, and 162.3 μg/mL, respectively, which were much higher than those for their effective nanomolar-level concentrations. Also, MK5, MK6, MK12, and MK14 decreased cell damage in H₂O₂-induced cells via a significant scavenging effect of reactive oxygen species. Molecular modeling was performed to rationalize the potential inhibitory activities of MK5, MK6, MK12, and MK14 toward MAO-B and their possible binding mechanisms, showing high-affinity binding pocket interactions and conformation perturbations of the compounds with MAO-B, which were interpreted as the conformational dynamics of MAO-B. This study concluded that all the compounds tested were more potent MAO-B inhibitors than the reference drugs, and leading compounds could be further explored for their effectiveness in various kinds of neurodegenerative disorders.