Search Results (261)

The present study investigated the neuroprotective potential of the Murraya carbazole derivatives murrayanol, mahanimbine, murrayafoline A, and 9-methyl-9H-carbazole-2-carbaldehyde using in silico and in vitro assays. The pharmacokinetic properties and potential toxicity (ADME/T) of the carbazole derivatives were assessed to evaluate their prospects as up-and-coming drug candidates. Molecular docking was used to investigate the interactions of the compounds with Aβ (PDB: 1IYT, 2BEG, and 8EZE) and AChE receptors (PDB: 4EY7 and 1C2B). The results from the in vitro assays were used to validate and support the findings from the in silico assays. The compounds demonstrated significant inhibition of acetylcholinesterase (AChE), a key target in neurodegenerative disorders. Murrayanol and mahanimbine presented superior inhibitory activity (IC₅₀ ~0.2 μg/mL), outperforming the reference drug, galantamine. The inhibition mechanisms were competitive (murrayanol, murrayafoline A, and 9-methyl-9H-carbazole-2-carbaldehyde) and non-competitive (mahanimbine), supported by low Ki values and strong docking affinities. The compounds also proved effective in reducing Aβ fibrillization (murrayanol: 40.83 ± 0.30%; murrayafoline A: 33.60 ± 0.55%, mahanimbine: 27.68 ± 2.71%). These findings highlight Murraya carbazoles as promising scaffolds for multifunctional agents in AD therapy. Further optimization and mechanistic studies are warranted to advance their development into clinically relevant neuroprotective agents. Full article

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by the accumulation of amyloid-β plaques, tau hyperphosphorylation, and chronic neuroinflammation. Emerging evidence suggests a crucial role of lipid signaling pathways in AD pathogenesis, particularly those mediated by autotaxin (ATX) and lysophosphatidic acid (LPA). ATX, an enzyme responsible for LPA production, has been implicated in neuroinflammatory processes, blood–brain barrier dysfunction, and neuronal degeneration. LPA signaling, through its interaction with specific G-protein-coupled receptors, influences neuroinflammation, synaptic plasticity, and tau pathology, all of which contribute to AD progression. This review synthesizes recent findings on the ATX/LPA axis in AD, exploring its potential as a biomarker and therapeutic target. Understanding the mechanistic links between ATX, LPA, and AD pathology may open new avenues for disease-modifying strategies. Full article

Cholinergic projections from the basal forebrain to the cortex and hippocampus play a critical role in cognitive functions, many of which rely on signaling through the alpha7 nicotinic acetylcholine receptor (α7nAChR). The Alzheimer’s disease (AD) brain is characterized by the profound impairment of the basal forebrain cholinergic system, including alterations in the levels of α7nAChR in various brain areas. In addition, α7nAChR binds with high affinity to beta amyloid (Aβ), suggesting α7nAChR might mediate some of Aβ’s effects in the brain. Under normal physiological conditions, the interaction between Aβ and α7nAChR appears to be beneficial, supporting normal neurotransmission, synaptic plasticity, and memory functions. However, when levels of Aβ are pathologically elevated, their interaction leads to deleterious effects, implicating α7nAChR in the pathophysiology of AD. In addition to expression in neurons, α7nAChR is expressed in astrocytes and microglia, where it serves as a key component of a cholinergic pathway that regulates neuroinflammation. This review article will cover the role of α7nAChR in neurons, astrocytes and microglia under normal conditions, summarize changes in the expression or function of α7nAChR in neurons and glia in the AD brain, and discuss cell-type specific contributions of α7nAChR to AD pathology with an emphasis on interactions of α7nAChR with Aβ. Full article

Alzheimer’s disease (AD), a progressive neurodegenerative disorder, is marked by the pathological accumulation of amyloid-β plaques and tau neurofibrillary tangles, both of which disrupt neuronal communication and function. Emerging evidence highlights the role of extracellular vesicles (EVs) as key mediators of intercellular communication, particularly in the propagation of pathological proteins in AD. Among the regulatory factors influencing EV composition and function, neuraminidase 1 (NEU1), a lysosomal sialidase responsible for desialylating glycoproteins has gained attention for its involvement in EV glycosylation. This review explores the role of NEU1 in modulating EV glycosylation, with particular emphasis on its influence on immune modulation and intracellular trafficking pathways and the subsequent impact on intercellular signaling and neurodegenerative progression. Altered NEU1 activity has been associated with abnormal glycan profiles on EVs, which may facilitate the enhanced spread of amyloid-β and tau proteins across neural networks. By regulating glycosylation, NEU1 influences EV stability, targeting and uptake by recipient cells, primarily through the desialylation of surface glycoproteins and glycolipids, which alters the EV charge, recognition and receptor-mediated interactions. Targeting NEU1 offers a promising therapeutic avenue to restore EV homeostasis and reduces pathological protein dissemination. However, challenges persist in developing selective NEU1 inhibitors and effective delivery methods to the brain. Furthermore, altered EV glycosylation patterns may serve as potential biomarkers for early AD diagnosis and monitoring. Overall, this review highlights the importance of NEU1 in AD pathogenesis and advocates for deeper investigation into its regulatory functions, with the aim of advancing therapeutic strategies and biomarker development for AD and related neurological disabilities. Full article

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline, memory loss and limited therapeutic options. Metal-based drugs have emerged as promising alternatives in the search for effective treatments, and vanadium coordination complexes have shown significant potential due to their neuroprotective and anti-aggregant properties. This review explores the advances in the development of vanadium-based metallodrugs for AD, focusing on their ability to modulate amyloid-beta (Aβ) aggregation, oxidative stress, and neuroinflammation. Recent in vitro and in vivo studies highlight the efficacy of oxovanadium (IV) and peroxovanadium (V) complexes in inhibiting Aβ fibril formation and reducing neuronal toxicity. Additionally, the interaction of vanadium complexes with key biological targets, such as peroxisome proliferator-activated receptor gamma (PPARγ) and protein-tyrosine phosphatase 1B (PTP1B), suggests a multifaceted therapeutic approach. While these findings underscore the potential of vanadium compounds as innovative treatments for AD, further research is needed to optimize their bioavailability, selectivity, and safety for clinical applications. Full article

Atopic dermatitis (AD) is a chronic inflammatory skin disorder marked by intricate interplay among skin barrier dysfunction, immune dysregulation, and microbial dysbiosis. While therapeutic advancements targeting T helper 2 (Th2) cytokines, such as interleukin (IL)-4 and IL-13, and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway have yielded promising outcomes, a significant proportion of patients still experience inadequate relief, particularly from persistent pruritus. Achieving minimal disease activity remains an unmet clinical priority and a cornerstone of effective AD management. This review provides an in-depth analysis of current therapeutic approaches and integrates findings from recent biologic studies, with a particular focus on innovative strategies under active investigation. These approaches include targeting components of the innate immune system, such as thymic stromal lymphopoietin (TSLP) and IL-1 family cytokines; the adaptive immune system, including OX40-OX40L interactions and Th17- and Th22-related cytokines; and mechanisms associated with pruritus, such as IL-31, histamine receptors, and neurokinin 1 receptor. Emerging insights underscore the transformative potential of personalized therapeutic regimens tailored to the distinct endotypes and severity of AD. Advances in deciphering the pathogenesis of AD are unlocking unprecedented opportunities for precision medicine, offering renewed hope for improved outcomes in this multifaceted and heterogeneous condition. Full article

Fatty acid contributes notably to meat nutrition value. A previous study investigated how complex plant extracts (CPE) can improve the fatty acid composition of ruminants, but the molecular mechanism remains unknown. This study aimed to examine the effect of dietary CPE supplementation on sheep growth performance and fatty acid composition in back fat (BF), combining lipidomics and transcriptomics analyses to explain the underlying mechanisms. Thirty-six female sheep, weighing 29.92 ± 2.52 kg and of a similar age (~4 months old), were randomly assigned into two groups: one received a basal diet (CTRL group), and the other received the same diet supplemented with 80 mg/kg of CPE (CPE group) for 75 days. The results revealed that the values of carcass fat content (GR) in the CPE group were significantly increased (p = 0.008), and the composition of fatty acid was changed. Lipidomic analysis indicated that CPE modulated lipid metabolism by regulating the contents of lipid molecules such as phosphatidylcholine (PC), fatty acyls (FAs), cardiolipin (CL), and triglyceride (TAG). After the addition of CPE, the lipid metabolism of BF was regulated mainly by regulating the glycerophospholipid metabolism, TNF signaling pathway, and cytokine–cytokine receptor interaction signaling pathway. These results revealed that changes in fatty acids were affected by the added CPE and corresponding molecular changes, which may provide new insights on the molecular level for applying CPE in sheep to improve fatty acid composition. Full article

Serotonin (5-HT) is a neurotransmitter that also plays an important role in the regulation of vascular tone and angiogenesis. This review focuses on the involvement of the 5-HT system in pathological processes leading to the development of Alzheimer’s disease (AD). There is evidence that damage or dysfunction of the 5-HT system contributes to the development of AD, and different subtypes of 5-HT receptors are a potential target for the treatment of AD. A link has been established between AD, depression, stress, and 5-HT deficiency in the brain. There are new data on the role of circadian rhythms in modulating stress, depression, and the 5-HT system; amyloid β (Aβ) plaque clearance; and AD progression. Circadian disruption inhibits Aβ plaque clearance and modulates AD progression. The properties and functions of 5-HT, its receptors, and serotonergic neurons are presented. Special attention is paid to the central role of 5-HT in brain development, including neurite outgrowth, regulation of somatic morphology, motility, synaptogenesis, control of dendritic spine shape and density, neuronal plasticity determining its role in network regeneration, and changes in innervation after brain damage. The results of different studies indicate that the interaction of amyloid β oligomers (AβO) with mitochondria is a sufficient trigger for AD-related neurodegeneration. The action of 5-HT leads to an improvement in mitochondrial quality and the restoration of brain areas after traumatic brain injury, chronic stress, or developmental disorders in AD. The role of a healthy lifestyle and drugs acting on serotonin receptors in the prevention and treatment of AD is discussed. Full article

The Schrödinger equation, Heisenberg’s uncertainty principles, and the Boltzmann constant represent transformative scientific achievements, the impacts of which extend far beyond their original domain of physics. As we celebrate the centenary of these fundamental quantum mechanical formulations, this review examines their evolution from abstract mathematical concepts to essential tools in contemporary drug discovery and development. While these principles describe the behavior of subatomic particles and molecules at the quantum level, they have profound implications for understanding biological processes such as enzyme catalysis, receptor–ligand interactions, and drug–target binding. Quantum tunneling, a direct consequence of these principles, explains how some reactions occur despite classical energy barriers, enabling novel therapeutic approaches for previously untreatable diseases. This understanding of quantum mechanics from 100 years ago is now creating innovative approaches to drug discovery with diverse prospects, as explored in this review. However, the fact that the quantum phenomenon can be described but never understood places us in a conundrum with both philosophical and ethical implications; a prospective and inconclusive discussion of these aspects is added to ensure the incompleteness of the paradigm remains unshifted. Full article

The formation of amyloid beta (Aβ) plaques is a central process in the development of Alzheimer’s disease (AD). Although its causative role or the effectiveness of therapeutic targeting is still debated, the key involvement of Aβ in the pathogenesis of neuroinflammation and neurodegeneration in AD is broadly accepted. In this review, we emphasize the role of lipid rafts, both in APP cleavage producing Aβ in neurons and in mediating Aβ inflammatory signaling in microglia. We introduce the term inflammarafts to characterize the Aβ-driven formation of enlarged, cholesterol-rich lipid rafts in activated microglia, which support protein–protein and lipid–protein interactions of inflammatory receptors. Examples reviewed include toll-like receptors (TLR2, TLR4), scavenger receptors (CD36, RAGE), and TREM2. The downstream pathways lead to the production of cytokines and reactive oxygen species, intensifying neuroinflammation and resulting in neuronal injury and cognitive decline. We further summarize emerging therapeutic strategies and emphasize the utility of apolipoprotein A-I binding protein (AIBP) in selective targeting of inflammarafts and attenuation of microglia-driven inflammation. Unlike the targeting of a single inflammatory receptor or a secretase, selective disruption of inflammarafts and preservation of physiological lipid rafts offer a novel approach to targeting multiple components and processes that contribute to neuroinflammation in AD. Full article

Brain-derived neurotrophic factor (BDNF) is critical for neuronal survival. Amyloid-β monomers (Aβ42M) and oligomers (Aβ42O) have trophic and toxic effects on neuronal survival, respectively. Branched oligosaccharides (BOs) and catechins (CAs) can specifically bind to Aβ42M/Aβ42O, influencing both effects. However, whether and how Aβ42M/Aβ42O influences BDNF remains unknown. This study investigated the interaction between Aβ42M/Aβ42O and BDNF, the effects of Aβ42M and Aβ42O on BDNF binding to the TrkB/p75 receptor and their impact on BDNF-supported cell survival, and the roles of BOs and CAs in these processes. BDNF exhibited stronger binding affinity for Aβ42M and Aβ42O than BOs/CAs. Aβ42M increased neuronal viability by synergistically enhancing BDNF binding to TrkB and p75, whereas Aβ42O decreased neuronal viability by inactivating/consuming BDNF, thereby reducing its binding to these receptors. BDNF-Aβ42O binding appeared to mutually neutralize/counteract each other’s biological effects; therefore, increasing BDNF levels might reduce Aβ42O’s neurotoxicity. By competitively targeting Aβ42M/Aβ42O rather than BDNF or its receptors, BOs and CAs enhanced these effects. These findings suggest that Aβ42M’s neurotrophicity was directly linked to its synergistic enhancement of BDNF activity, whereas Aβ42O’s neurotoxicity was primarily due to its inactivation or consumption of BDNF. This study provided valuable insights for developing BOs/CAs-based neuroprotective therapeutics or nanomaterials against AD. Full article

Background/Objectives: Gelsolin (GSN) is an actin-binding protein that helps maintain neuronal structure and shape, regulates neuronal growth, and apoptosis. Our previous work demonstrated that GSN associated with estrogen receptor beta (ERβ1) in the brains of female rats, but this association was lost in advanced age. GSN was also required for ERβ1-mediated transcriptional repression at activator protein-1 (AP-1) motifs upstream of a minimal gene promoter. However, the consequences of the loss of GSN:ERβ1 protein interaction on ERβ1 nuclear translocation and transcriptional repression at AP-1 sites located within complex endogenous gene promoters remained unclear. Methods: We used immunofluorescent super resolution microscopy and luciferase reporter assays to test the hypothesis that GSN facilitates ERβ1 nuclear translocation and transcriptional repression of two genes relevant for Alzheimer Disease: APP (amyloid-beta precursor protein) and ITPKB (inositol-1,4,5-trisphosphate 3-kinase B). Results: Our results revealed the novel finding that GSN is required for ERβ1 ligand-independent nuclear translocation in neuronal cells. Moreover, we show that GSN increased APP and ITPKB promoter activity, which was repressed by ERβ1. Conclusions: Together, these data revealed the importance of the cytoskeletal protein, GSN, in regulating intracellular trafficking of nuclear receptors and demonstrate the first evidence of ERβ1 directly regulating two genes that are implicated in the progression of AD. Full article

Alzheimer’s disease (AD) is a neurodegenerative disease marked by the accumulation of toxic amyloid-beta (Aβ) oligomers. These oligomers are thought to cause synaptic dysfunction and contribute to neurodegeneration. CT1812 is a small-molecule sigma-2 receptor antagonist that is currently being investigated and tested as a potential disease-modifying treatment for AD. CT1812 acts by displacing Aβ oligomers into the cerebrospinal fluid and preventing their interaction with receptors on neurons. Preclinical studies and early clinical trials of CT1812 show promising results and provide evidence for its potential to slow AD progression. This review outlines the role of Aβ oligomers in AD, CT1812’s mechanism of action, and the effectiveness and limitations of CT1812 based on preclinical and clinical studies. Full article

Clinical data as well as animal and cell studies indicate that certain antidiabetic drugs, including glucagon-like peptide 1 receptor agonists (GLP-1RAs), exert therapeutic effects in Alzheimer’s disease (AD) by modulating amyloid-β peptide (Aβ) metabolism. Meanwhile, the direct interactions between GLP-1RAs and Aβ and their functional consequences remain unexplored. In this study, the interactions between monomeric Aβ40/Aβ42 of GLP-1(7-37) and its several analogs (semaglutide (Sema), liraglutide (Lira), exenatide (Exen)) were studied using biolayer interferometry and surface plasmon resonance spectroscopy. The quaternary structure of GLP-1RAs was investigated using dynamic light scattering. The effects of GLP-1RAs on Aβ fibrillation were assessed using the thioflavin T assay and electron microscopy. The impact of GLP-1RAs on Aβ cytotoxicity was evaluated via the MTT assay. Monomeric Aβ40 and Aβ42 directly bind to GLP-1(7-37), Sema, Lira, and Exen, with the highest affinity for Lira (the lowest estimates of equilibrium dissociation constants were 42–60 nM). GLP-1RAs are prone to oligomerization, which may affect their binding to Aβ. GLP-1(7-37) and Exen inhibit Aβ40 fibrillation, whereas Sema promotes it. GLP-1 analogs decrease Aβ cytotoxicity toward SH-SY5Y cells, while GLP-1(7-37) enhances Aβ40 cytotoxicity without affecting the cytotoxic effect of Aβ42. Overall, GLP-1RAs interact with Aβ and differentially modulate its fibrillation and cytotoxicity, suggesting the need for further studies of our observed effects in vivo. Full article

The tetrameric protein transthyretin (TTR) transports the hormone thyroxine in plasma and cerebrospinal fluid. Certain point mutations of TTR, including the Val122Ile mutation investigated here, destabilize the tetramer leading to its dissociation, misfolding, aggregation, and the eventual buildup of amyloid fibrils in the myocardium. Cioffi et al. reported the design and synthesis of a novel TTR kinetic stabilizing ligand, referred to here as TKS14, that inhibited TTR dissociation and amyloid fibril formation. In this study, molecular dynamics simulations were used to investigate the binding of TKS14 and eight TSK14 derivatives to the Val122Ile TTR mutant. For each complex, the ligand’s solvent accessible surface area (SASA), ligand–receptor hydrogen-bonding interactions, and the free energy of ligand-binding to TTR were investigated. The goal of this study was to identify the TSK14 functional groups that contributed to TTR stabilization. TKS14 was found to form a stable, two-point interaction with TTR by hydrogen bonding to Ser-117 residues in the inner receptor binding pocket and interacting through hydrogen bonds and electrostatically with Lys-15 residues near the receptor’s surface. The free energy of TKS14-TTR binding was −18.0 kcal mol⁻¹ and the ligand’s average SASA value decreased by over 80% upon binding to the receptor. The thermodynamic favorability of TTR binding decreased when TKS14 derivatives contained either methyl ester, amide, tetrazole, or N-methyl functional groups that disrupted the above two-point interaction. One derivative in which a tetrazole ring was added to TKS14 was found to form hydrogen bonds with Thr-106, Thr-119, Ser-117, and Lys-15 residues. This derivative had a free energy of TTR binding of −21.4 kcal mol⁻¹. Overall, the molecular dynamics simulations showed that the functional groups within the TKS14 structural template can be tuned to optimize the thermodynamic favorability of ligand binding. Full article