ABSTRACT
Developing multitargeted ligands as promising therapeutics for Alzheimer's disease (AD) has been considered important. Herein, a novel class of cinnamamide/ester-triazole hybrids with multifaceted effects on AD was developed based on the multitarget-directed ligands strategy. Thirty-seven cinnamamide/ester-triazole hybrids were synthesized, with most exhibiting significant inhibitory activity against Aß-induced toxicity at a single concentration in vitro. The most optimal hybrid compound 4j inhibited copper-induced Aß toxicity in AD cells. its action was superior to that of donepezil and memantine. It also moderately inhibited intracellular AChE activity and presented favorable bioavailability and blood-brain barrier penetration with low toxicity in vivo. Of note, it ameliorated cognitive impairment, neuronal degeneration, and Aß deposition in Aß1-42-injured mice. Mechanistically, the compound regulated APP processing by promoting the ADAM10-associated nonamyloidogenic signaling and inhibiting the BACE1-mediated amyloidogenic pathway. Moreover, it suppressed intracellular AChE activity and tau phosphorylation. Therefore, compound 4j may be a promising multitargeted active molecule against AD.
Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Cinnamates , Triazoles , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Animals , Triazoles/chemistry , Triazoles/pharmacology , Triazoles/chemical synthesis , Cinnamates/chemistry , Cinnamates/pharmacology , Cinnamates/chemical synthesis , Humans , Mice , Amyloid beta-Peptides/metabolism , Amyloid beta-Peptides/antagonists & inhibitors , Structure-Activity Relationship , Molecular Structure , Esters/chemistry , Esters/pharmacology , Esters/chemical synthesis , Dose-Response Relationship, Drug , Acetylcholinesterase/metabolism , Cholinesterase Inhibitors/chemistry , Cholinesterase Inhibitors/pharmacology , Cholinesterase Inhibitors/chemical synthesis , Drug Discovery , Neuroprotective Agents/chemistry , Neuroprotective Agents/pharmacology , Neuroprotective Agents/chemical synthesis , Peptide Fragments/metabolism , Peptide Fragments/antagonists & inhibitors , MaleABSTRACT
There is a growing interest in the search for metal-based therapeutics for protein misfolding disorders such as Alzheimer's disease (AD). A novel and largely unexplored class of metallodrugs is constituted by paddlewheel diruthenium complexes, which exhibit unusual water solubility and stability and unique coordination modes to proteins. Here, we investigate the ability of the complexes [Ru2Cl(DPhF)(O2CCH3)3]·H2O (1), [Ru2Cl(DPhF)2(O2CCH3)2]·H2O (2), and K2[Ru2(DPhF)(CO3)3]·3H2O (3) (DPhF- = N,N'-diphenylformamidinate) to interfere with the amyloid aggregation of the Aß1-42 peptide. These compounds differ in charge and steric hindrance due to the coordination of a different number of bulky ligands. The mechanisms of action of the three complexes were studied by employing a plethora of physicochemical and biophysical techniques as well as cellular assays. All these studies converge on different mechanisms of inhibition of amyloid fibrillation: complexes 1 and 2 show a clear inhibitory effect due to an exchange ligand process in the Ru2 unit aided by aromatic interactions. Complex 3 shows no inhibition of aggregation, probably due to its negative charge in solution. This study demonstrates that slight variations in the ligands surrounding the bimetallic core can modulate the amyloid aggregation inhibition and supports the use of paddlewheel diruthenium complexes as promising therapeutics for Alzheimer's disease.
Subject(s)
Amyloid beta-Peptides , Coordination Complexes , Peptide Fragments , Ruthenium , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/metabolism , Amyloid beta-Peptides/chemistry , Ruthenium/chemistry , Ruthenium/pharmacology , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Coordination Complexes/chemical synthesis , Peptide Fragments/chemistry , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/metabolism , Humans , Protein Aggregates/drug effects , Molecular Structure , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolismABSTRACT
Alzheimer's disease (AD) is a chronic neurodegenerative disease characterized by progressive memory loss and behavioral disorders. The excessive accumulation of amyloid ß (Aß) and the formation of neurofibrillary tangles (NFTs) damage synaptic connections and the death of neurons. However, the underlying mechanisms of pathogenesis of AD remain unclear. Growing evidence indicates that impaired mitochondrial function may play a crucial role in the development of AD. In the current study, we investigated whether nicotinic acid (NA) could protect against amyloid ß1-42-induced cytotoxicity in differentiated SH-SY5Y cells. Our results revealed the neuroprotective effects of NA on the differentiated SH-SY5Y cells treated with Aß1-42. In detail, the 1-h pre-incubation with NA increased cell viability and lowered LDH levels. NA pre-incubation abolished Aß1-42 treatment-associated alterations of mRNA levels of synaptic genes and enhanced the relative ß3 Tubulin fluorescence intensity. NA eliminated the Aß1-42-induced mitochondrial dysfunction by increasing the potential of mitochondrial membranes and maintaining a balance between the fusion and fission of mitochondria. Moreover, Aß1-42 decreased mRNA levels of anti-apoptotic bcl2 and increased mRNA levels of pro-apoptotic: bim, bak, cytochrome c, and caspase 9. At the same time, the NA pre-treatment reduced Aß1-42-dependent apoptotic death of differentiated SH-SY5Y cells. The above data suggest that NA presents a protective activity against Aß1-42-induced cytotoxicity in differentiated SH-SY5Y cells by inhibiting the mitochondrial pathway of apoptosis and restoring the proper function of mitochondria.
Subject(s)
Amyloid beta-Peptides , Apoptosis , Cell Differentiation , Mitochondria , Niacin , Peptide Fragments , Amyloid beta-Peptides/toxicity , Humans , Mitochondria/drug effects , Mitochondria/metabolism , Apoptosis/drug effects , Peptide Fragments/toxicity , Peptide Fragments/antagonists & inhibitors , Cell Line, Tumor , Cell Differentiation/drug effects , Niacin/pharmacology , Neuroprotective Agents/pharmacology , Cell Survival/drug effects , Cell Survival/physiologyABSTRACT
Background: Inhibition of amyloid ß protein fragment (Aß) aggregation is considered to be one of the most effective strategies for the treatment of Alzheimer's disease. (-)-Epigallocatechin-3-gallate (EGCG) has been found to be effective in this regard; however, owing to its low bioavailability, nanodelivery is recommended for practical applications. Compared to chemical reduction methods, biosynthesis avoids possible biotoxicity and cumbersome preparation processes. Materials and Methods: The interaction between EGCG and Aß42 was simulated by molecular docking, and green tea-conjugated gold nanoparticles (GT-Au NPs) and EGCG-Au NPs were synthesized using EGCG-enriched green tea and EGCG solutions, respectively. Surface active molecules of the particles were identified and analyzed using various liquid chromatography-tandem triple quadrupole mass spectrometry methods. ThT fluorescence assay, circular dichroism, and TEM were used to investigate the effect of synthesized particles on the inhibition of Aß42 aggregation. Results: EGCG as well as apigenin, quercetin, baicalin, and glutathione were identified as capping ligands stabilized on the surface of GT-Au NPs. They more or less inhibited Aß42 aggregation or promoted fibril disaggregation, with EGCG being the most effective, which bound to Aß42 through hydrogen bonding, hydrophobic interactions, etc. resulting in 39.86% and 88.50% inhibition of aggregation and disaggregation effects, respectively. EGCG-Au NPs were not as effective as free EGCG, whereas multiple thiols and polyphenols in green tea accelerated and optimized heavy metal detoxification. The synthesized GT-Au NPs conferred the efficacy of diverse ligands to the particles, with inhibition of aggregation and disaggregation effects of 54.69% and 88.75%, respectively, while increasing the yield, enhancing water solubility, and decreasing cost. Conclusion: Biosynthesis of nanoparticles using green tea is a promising simple and economical drug-carrying approach to confer multiple pharmacophore molecules to Au NPs. This could be used to design new drug candidates to treat Alzheimer's disease.
Subject(s)
Amyloid beta-Peptides , Metal Nanoparticles , Peptide Fragments , Humans , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/metabolism , Catechin/chemistry , Catechin/pharmacology , Catechin/analogs & derivatives , Gold/chemistry , Ligands , Metal Nanoparticles/chemistry , Metal Nanoparticles/therapeutic use , Molecular Docking Simulation , Peptide Fragments/chemistry , Peptide Fragments/antagonists & inhibitors , Protein Aggregates/drug effects , Camellia sinensis/chemistryABSTRACT
Aß1-42 and acetylcholinesterase (AChE) are two key therapeutic targets for Alzheimer's disease (AD). The purpose of this study is to develop a dual-target inhibitor that inhibits both of these targets by fusing the chemical structure of baicalein and donepezil. Among them, we modified the structure of baicalein to arylcoumarin, synthesized three kinds of structural compounds, and evaluated their biological activities. The results showed that compound 3b had the strongest inhibitory effect on AChE (IC50 = 0.05 ± 0.02 µM), which was better than those of donepezil and baicalein. In addition, compound 3b has a strong ability to inhibit the aggregation of Aß1-42 and protect nerve cells, and it can also penetrate the blood-brain barrier well. Using a zebrafish behavioral analyzer test, it was found that compound 3b can alleviate the behavioral effects of AlCl3-induced zebrafish larval movement retardation, which has a certain guiding significance for simulating the movement disorders of AD patients. In summary, compound 3b is expected to become a multifunctional agent for treating and alleviating the symptoms of AD patients.
Subject(s)
Acetylcholinesterase , Alzheimer Disease , Amyloid beta-Peptides , Cholinesterase Inhibitors , Drug Design , Zebrafish , Alzheimer Disease/drug therapy , Animals , Cholinesterase Inhibitors/pharmacology , Cholinesterase Inhibitors/chemical synthesis , Cholinesterase Inhibitors/chemistry , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/metabolism , Structure-Activity Relationship , Acetylcholinesterase/metabolism , Humans , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/pharmacology , Donepezil/pharmacology , Donepezil/chemical synthesis , Donepezil/chemistry , Blood-Brain Barrier/metabolism , Molecular Structure , Flavanones/pharmacology , Flavanones/chemical synthesis , Flavanones/chemistry , Dose-Response Relationship, Drug , Behavior, Animal/drug effectsABSTRACT
AD is the most common neurodegenerative disorder characterized by progressive memory impairment and cognitive deficits. The pathology of AD is still unclear; however, several studies have shown that the aggregation of the Aß peptide in the CNS is an exclusively pathological process involved in AD. Currently, there is no proven medication to cure or prevent the disease progression. Nevertheless, various therapeutic approaches for AD show only relief of symptoms and mostly work on cognitive recovery. However, one of the promising approaches for therapeutic intervention is to use inhibitors for blocking the Aß peptide aggregation process. Recently, herbal phenolic compounds have been shown to have a therapeutic property for treatment of AD due to their multifaceted action. In this study, we investigated the effectiveness of SA, Gn Rb1, and DMyr on inhibiting the aggregation and toxicity of Aß40 and Aß42 using different biochemical and cell-based assays. Our results showed that SA and DMyr inhibit Aß40 and Aß42 fibrillation, seeded aggregation, and toxicity. Gn Rb1 did not have any effect on the aggregation or toxicity induced by Aß40 and Aß42. Moreover, SA and DMyr were able to disaggregate the preformed fibrils. Overall, these compounds may be used alone or synergistically and could be considered as a lead for designing new compounds that could be used as effective treatment of AD and related disorders.
Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Cognitive Dysfunction , Peptide Fragments , Humans , Alzheimer Disease/drug therapy , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/metabolism , Cognitive Dysfunction/drug therapy , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/metabolismABSTRACT
BACKGROUND & AIMS: Fatty acid translocase CD36 (CD36/FAT) is a widely expressed membrane protein with multiple immuno-metabolic functions. Genetic CD36 deficiency is associated with increased risk of metabolic dysfunction-associated fatty liver disease (MAFLD) in patients. Liver fibrosis severity mainly affects the prognosis in patients with MAFLD, but the role of hepatocyte CD36 in liver fibrosis of MAFLD remains unclear. METHODS: A high-fat high-cholesterol diet and a high-fat diet with high-fructose drinking water were used to induce nonalcoholic steatohepatitis (NASH) in hepatocyte-specific CD36 knockout (CD36LKO) and CD36flox/flox (LWT) mice. Human hepG2 cell line was used to investigate the role of CD36 in regulating Notch pathway in vitro. RESULTS: Compared to LWT mice, CD36LKO mice were susceptible to NASH diet-induced liver injury and fibrosis. The analysis of RNA-sequencing data revealed that Notch pathway was activated in CD36LKO mice. LY3039478, an inhibitor of γ-secretase, inhibited Notch1 protein S3 cleavage and Notch1 intracellular domain (N1ICD) production, alleviating liver injury and fibrosis in CD36LKO mice livers. Likewise, both LY3039478 and knockdown of Notch1 inhibited the CD36KO-induced increase of N1ICD production, causing the decrease of fibrogenic markers in CD36KO HepG2 cells. Mechanistically, CD36 formed a complex with Notch1 and γ-secretase in lipid rafts, and hence CD36 anchored Notch1 in lipid rafts domains and blocked Notch1/γ-secretase interaction, inhibiting γ-secretase-mediated cleavage of Notch1 and the production of N1ICD. CONCLUSIONS: Hepatocyte CD36 plays a key role in protecting mice from diet-induced liver injury and fibrosis, which may provide a potential therapeutic strategy for preventing liver fibrogenesis in MAFLD.
Subject(s)
CD36 Antigens , Diet , Hepatocytes , Liver Cirrhosis , Non-alcoholic Fatty Liver Disease , Peptide Fragments , Receptor, Notch1 , Animals , Mice , Amyloid Precursor Protein Secretases/antagonists & inhibitors , CD36 Antigens/deficiency , CD36 Antigens/genetics , CD36 Antigens/metabolism , Diet/adverse effects , Gene Deletion , Hep G2 Cells , Hepatocytes/metabolism , Liver Cirrhosis/etiology , Liver Cirrhosis/genetics , Liver Cirrhosis/prevention & control , Membrane Microdomains , Non-alcoholic Fatty Liver Disease/etiology , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/prevention & control , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/chemistry , Peptide Fragments/metabolism , Phenotype , Receptor, Notch1/chemistry , Receptor, Notch1/metabolism , Signal Transduction , HumansABSTRACT
Mitochondria-ER contact sites (MERCs) orchestrate many important cellular functions including regulating mitochondrial quality control through mitophagy and mediating mitochondrial calcium uptake. Here, we identify and functionally characterize the Drosophila ortholog of the recently identified mammalian MERC protein, Pdzd8. We find that reducing pdzd8-mediated MERCs in neurons slows age-associated decline in locomotor activity and increases lifespan in Drosophila. The protective effects of pdzd8 knockdown in neurons correlate with an increase in mitophagy, suggesting that increased mitochondrial turnover may support healthy aging of neurons. In contrast, increasing MERCs by expressing a constitutive, synthetic ER-mitochondria tether disrupts mitochondrial transport and synapse formation, accelerates age-related decline in locomotion, and reduces lifespan. Although depletion of pdzd8 prolongs the survival of flies fed with mitochondrial toxins, it is also sufficient to rescue locomotor defects of a fly model of Alzheimer's disease expressing Amyloid ß42 (Aß42). Together, our results provide the first in vivo evidence that MERCs mediated by the tethering protein pdzd8 play a critical role in the regulation of mitochondrial quality control and neuronal homeostasis.
Subject(s)
Amyloid beta-Peptides , Drosophila Proteins , Drosophila melanogaster , Endoplasmic Reticulum , Mitochondria , Peptide Fragments , Alzheimer Disease , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/toxicity , Animals , Cellular Senescence , Disease Models, Animal , Drosophila Proteins/deficiency , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Drosophila melanogaster/cytology , Drosophila melanogaster/drug effects , Drosophila melanogaster/metabolism , Drosophila melanogaster/physiology , Endoplasmic Reticulum/drug effects , Endoplasmic Reticulum/metabolism , Gene Knockdown Techniques , Genetic Fitness , Locomotion/drug effects , Longevity/drug effects , Mitochondria/drug effects , Mitochondria/metabolism , Mitochondrial Dynamics/drug effects , Mitophagy/drug effects , Neurons/drug effects , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/toxicityABSTRACT
BACKGROUND: Immunotransmitters (e.g., neurotransmitters and neuromodulators) could orchestrate diverse immune responses; however, the elaborated mechanism by which melatonergic activation governs inflammation remains less defined. METHODS: Primary macrophages, various cell lines, and Pasteurella multocida (PmCQ2)-infected mice were respectively used to illustrate the influence of melatonergic signalling on inflammation in vitro and in vivo. A series of methods (e.g., RNA-seq, metabolomics, and genetic manipulation) were conducted to reveal the mechanism whereby melatonergic signalling reduces macrophage inflammation. RESULTS: Here, we demonstrate that melatonergic activation substantially lessens interleukin (IL)-1ß-dependent inflammation. Treatment of macrophages with melatonin rewires metabolic program, as well as remodels signalling pathways which depends on interferon regulatory factor (IRF) 7. Mechanistically, melatonin acts via membrane receptor (MT) 1 to increase heat shock factor (Hsf) 1 expression through lowering the inactive glycogen synthase kinase (GSK3) ß, thereby transcriptionally inhibiting interferon (IFN)-γ receptor (IFNGR) 2 and ultimately causing defective canonical signalling events [Janus kinase (JAK) 1/2-signal transducer and activator of transcription (STAT) 1-IRF7] and lower IL-1ß production in macrophages. Moreover, we find that melatonin amplifies host protective responses to PmCQ2 infection-induced pneumonia. CONCLUSIONS: Our conceptual framework provides potential therapeutic targets to prevent and/or treat inflammatory diseases associating with excessive IL-1ß production.
Subject(s)
Inflammation/drug therapy , Interleukin-1beta/antagonists & inhibitors , Peptide Fragments/antagonists & inhibitors , Receptors, Interferon/drug effects , Animals , China , Disease Models, Animal , Inflammation/physiopathology , Inflammation/prevention & control , Mice , Receptors, Interferon/metabolism , Signal Transduction/drug effectsABSTRACT
The VEGF-A-induced functional impairment of the barrier formed by retinal endothelial cells (REC) can be prevented and even - at least temporarily - reverted by trapping the growth factor in a complex with a VEGF-binding protein or by inhibiting the activity of the VEGF receptor 2 (VEGFR2). In an approach to emulate the clinically relevant situation of constant exposure to effectors, we investigated (1) whether prolonged exposure to VEGF-A165 for up to six days results in a different type of disturbance of the barrier formed by immortalized bovine REC (iBREC) and (2) whether alterations of the barrier induced by VEGF-A165 can indeed be sustainably reverted by subsequent treatment with the VEGF-A-binding proteins ranibizumab or brolucizumab. As a measure of barrier integrity, the cell index (CI) of iBREC cultivated on gold electrodes was monitored continuously. CI values declined shortly after addition of the growth factor and then remained low for more than six days over which considerable amounts of both extra- and intracellular VEGF-A were measured. Interestingly, the specific VEGFR2 inhibitor nintedanib normalized the lowered CI when added to iBREC pre-treated with VEGF-A165 for one day, but failed to do so when cells had been exposed to the growth factor for six days. Expression of the tight junction (TJ) protein claudin-5 was unchanged early after addition of VEGF-A165 but higher after prolonged treatment, whereas decreased amounts of the TJ-protein claudin-1 remained low, and increased expression of the plasmalemma vesicle-associated protein (PLVAP) remained high during further exposure. After two days, the characteristic even plasma membrane stainings of claudin-1 or claudin-5 appeared weaker or disordered, respectively. After six days the subcellular localization of claudin-5 was similar to that of control cells again, but claudin-1 remained relocated from the plasma membrane. To counteract these effects of VEGF-A165, brolucizumab or ranibizumab was added after one day, resulting in recovery of the then lowered CI to normal values within a few hours. However, despite the VEGF antagonist being present, the CI declined again two days later to values that were just slightly higher than without VEGF inhibition during further assessment for several days. At this stage, neither the supernatants nor whole cell extracts from iBREC treated with VEGF-A165 and its antagonists contained significant amounts of free VEGF-A. Treatment of VEGF-A165-challenged iBREC with ranibizumab or brolucizumab normalized expression of claudin-1 and claudin-5, but not completely that of PLVAP. Interestingly, the characteristic VEGF-A165-induced relocalization of claudin-1 from the plasma membrane was reverted within one day by any of the VEGF antagonists, but reappeared despite their presence after further exposure for several days. Taken together, barrier dysfunction induced by VEGF-A165 results from deregulated para- and transcellular flow but the precise nature or magnitude of underlying changes on a molecular level clearly depend on the time of exposure, evolving into a stage of VEGF-A165-independent barrier impairment. These findings also provide a plausible explanation for resistance to treatment with VEGF-A antagonists frequently observed in clinical practice.
Subject(s)
Endothelial Cells/drug effects , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/pharmacology , Retinal Vessels/cytology , Tight Junctions/drug effects , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Vascular Endothelial Growth Factor A/pharmacology , Angiogenesis Inhibitors/therapeutic use , Animals , Antibodies, Monoclonal, Humanized/therapeutic use , Biological Transport , Blotting, Western , Cattle , Cell Movement/drug effects , Cells, Cultured , Claudin-1/metabolism , Claudin-5/metabolism , Electrophoresis, Polyacrylamide Gel , Endothelial Cells/metabolism , Enzyme-Linked Immunosorbent Assay , Humans , Ranibizumab/therapeutic useSubject(s)
Apolipoproteins E/antagonists & inhibitors , Neurotoxins/biosynthesis , Peptide Fragments/antagonists & inhibitors , Receptors, Nicotinic/drug effects , Stroke/complications , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Apolipoproteins E/therapeutic use , Humans , Peptide Fragments/therapeutic use , Stroke/blood , Stroke/drug therapyABSTRACT
In this work, a series of naringenin-O-carbamate derivatives was designed and synthesized as multifunctional agents for the treatment of Alzheimer's disease (AD) through multi-target-directed ligands (MTDLs) strategy. The biological activity in vitro showed that compound 3c showed good antioxidant potency (ORAC = 1.0 eq), and it was a reversible huAChE (IC50 = 9.7 µM) inhibitor. In addition, compound 3c significantly inhibited self-induced Aß1-42 aggregation, and it could activate UPS degradation pathway in HT22 cells and clear the aggregated proteins associated with AD. Moreover, compound 3c was a selective metal chelator, and it significantly inhibited and disaggregated Cu2+-mediated Aß1-42 aggregation. Furthermore, compound 3c displayed remarkable neuroprotective effect and anti-inflammatory property. Interestingly, compound 3c displayed good hepatoprotective effect by its antioxidant activity. More importantly, compound 3c demonstrated favourable blood-brain barrier penetration in vitro and drug-like property. Therefore, compound 3c was a promising multifunctional agent for the treatment of AD.
Subject(s)
Alzheimer Disease/drug therapy , Antioxidants/pharmacology , Carbamates/pharmacology , Cholinesterase Inhibitors/pharmacology , Flavanones/pharmacology , Neuroprotective Agents/pharmacology , Acetylcholinesterase/metabolism , Alzheimer Disease/metabolism , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/metabolism , Animals , Antioxidants/chemical synthesis , Antioxidants/chemistry , Butyrylcholinesterase/metabolism , Carbamates/chemical synthesis , Carbamates/chemistry , Cell Line , Cell Survival/drug effects , Cholinesterase Inhibitors/chemical synthesis , Cholinesterase Inhibitors/chemistry , Copper/pharmacology , Dose-Response Relationship, Drug , Drug Development , Flavanones/chemical synthesis , Flavanones/chemistry , Humans , Molecular Structure , Neuroprotective Agents/chemical synthesis , Neuroprotective Agents/chemistry , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/metabolism , Protein Aggregates/drug effects , Rats , Structure-Activity RelationshipABSTRACT
Pathological aggregation of amyloid polypeptides is associated with numerous degenerative diseases. Preventing aggregation and clearing amyloid deposits are considered as promising strategies against amyloidosis. With the capacity of crossing the blood-brain barrier and good biocompatibility, the hydroxylated single-walled carbon nanotube (SWCNT-OH) has been shown with excellent anti-amyloid properties. Here, we systematically studied the SWCNT-OH effects on the fibrillization of the ß2m21-31 peptides utilizing all-atom discrete molecular dynamics (DMD) simulation. Our results demonstrated the isolated ß2m21-31 peptides first nucleated into unstructured oligomers followed by coil-to-sheet conformational conversions in oligomers with at least six peptides. The elongation and lateral surfaces of the preformed ß-sheet could catalyze the other unstructured monomers and small oligomers converted into ß-sheet formations via dock-lock fibril growth and secondary nucleation processes. Eventually, the ß2m21-31 peptides would self-assemble into well-ordered cross-ß structures. Regardless of isolated monomers or well-defined cross-ß assemblies, the ß2m21-31 would attach on the surfaces of SWCNT-OH adopting unstructured formations indicating the SWCNT-OH not only inhibited the fibrillization of ß2m21-31 but also destroyed pre-formed proto-fibrils. Overall, our study displays a complete picture of the fibrillization mechanism of ß2m21-31 and the amyloid inhibitory mechanism of SWCNT-OH, offering new insight into the de-novo design of anti-amyloid inhibitors.
Subject(s)
Amyloid beta-Peptides , Nanotubes, Carbon/chemistry , Peptide Fragments , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/chemistry , Humans , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/chemistry , Protein Aggregation, PathologicalABSTRACT
Glycogen synthase kinase-3 (GSK-3) is a critical molecule in Alzheimer's disease (AD) that modulates two histopathological hallmarks of AD: Amyloid beta (Aß) plaques and neurofibrillary tangles composed of aberrant hyper-phosphorylation of tau protein. This study was performed to investigate the protective effect of flavone apigenin through inhibition of GSK-3 and the involvement of this kinase in the inhibition of BACE1 expression and hyperphosphorylation of tau protein in an AD rat model. 15 nM of aggregated amyloid-beta 25-35 was microinjected into the left lateral ventricle of an AD rat. Apigenin (50 mg/kg) was administered orally 45 min before the Aß injection and continued daily for three weeks. Immunohistochemistry and western blot analysis showed that apigenin significantly reduced the hyperphosphorylation of tau levels in the hippocampus. Real-time PCR analysis revealed significant inhibition of the mRNA level of ß secretase (BACE1) and GSK-3ß, but Apigenin had no effect on the level of GSK-3α. The results demonstrate that apigenin has a protective effect against amyloid-beta 25-35 by decreasing the expression of GSK-3ß with the consequence of lowering the hyperphosphorylation of tau protein and suppressing BACE1 expression.
Subject(s)
Alzheimer Disease/genetics , Alzheimer Disease/prevention & control , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/toxicity , Apigenin/pharmacology , Glycogen Synthase Kinase 3 beta/drug effects , Neuroprotective Agents/pharmacology , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/toxicity , Amyloid Precursor Protein Secretases/biosynthesis , Amyloid Precursor Protein Secretases/genetics , Animals , Aspartic Acid Endopeptidases/biosynthesis , Aspartic Acid Endopeptidases/genetics , Immunohistochemistry , Male , Phosphorylation , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Rats , Rats, Wistar , tau Proteins/metabolismABSTRACT
Alzheimer's disease (AD) is a prevalent neurodegenerative disorder that has multiple causes. Therefore, multiple-target-directed ligands (MTDLs), which act on multiple targets, have been developed as a novel strategy for AD therapy. In this study, novel drug candidates were designed and synthesized by the covalent linkings of tacrine, a previously used anti-AD acetylcholinesterase (AChE) inhibitor, and dipicolylamine, an ß-amyloid (Aß) aggregation inhibitor. Most tacrine-dipicolylamine dimers potently inhibited AChE and Aß1-42 aggregation in vitro, and 13a exhibited nanomolar level inhibition. Molecular docking analysis suggested that 13a could interact with the catalytic active sites and the peripheral anion site of AChE, and bind to Aß1-42 pentamers. Moreover, 13a effectively attenuated Aß1-42 oligomers-induced cognitive dysfunction in mice by activating the cAMP-response element binding protein/brain-derived neurotrophic factor signaling pathway, decreasing tau phosphorylation, preventing synaptic toxicity, and inhibiting neuroinflammation. The safety profile of 13a in mice was demonstrated by acute toxicity experiments. All these results suggested that novel tacrine-dipicolylamine dimers, especially 13a, have multi-target neuroprotective and cognitive-enhancing potentials, and therefore might be developed as MTDLs to combat AD.
Subject(s)
Alzheimer Disease/drug therapy , Amines/pharmacology , Cholinesterase Inhibitors/pharmacology , Drug Design , Neuroprotective Agents/pharmacology , Picolinic Acids/pharmacology , Tacrine/pharmacology , Acetylcholinesterase/metabolism , Alzheimer Disease/metabolism , Amines/chemistry , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/metabolism , Cholinesterase Inhibitors/chemical synthesis , Cholinesterase Inhibitors/chemistry , Dose-Response Relationship, Drug , Humans , Ligands , Molecular Structure , Neuroprotective Agents/chemical synthesis , Neuroprotective Agents/chemistry , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/metabolism , Picolinic Acids/chemistry , Protein Aggregates/drug effects , Structure-Activity Relationship , Tacrine/chemistryABSTRACT
Human immunodeficiency virus (HIV)-1-specific broadly neutralizing monoclonal antibodies are currently under development to treat and prevent HIV-1 infection. We performed a single-center, randomized, double-blind, dose-escalation, placebo-controlled trial of a single administration of the HIV-1 V3-glycan-specific antibody PGT121 at 3, 10 and 30 mg kg-1 in HIV-uninfected adults and HIV-infected adults on antiretroviral therapy (ART), as well as a multicenter, open-label trial of one infusion of PGT121 at 30 mg kg-1 in viremic HIV-infected adults not on ART (no. NCT02960581). The primary endpoints were safety and tolerability, pharmacokinetics (PK) and antiviral activity in viremic HIV-infected adults not on ART. The secondary endpoints were changes in anti-PGT121 antibody titers and CD4+ T-cell count, and development of HIV-1 sequence variations associated with PGT121 resistance. Among 48 participants enrolled, no treatment-related serious adverse events, potential immune-mediated diseases or Grade 3 or higher adverse events were reported. The most common reactions among PGT121 recipients were intravenous/injection site tenderness, pain and headache. Absolute and relative CD4+ T-cell counts did not change following PGT121 infusion in HIV-infected participants. Neutralizing anti-drug antibodies were not elicited. PGT121 reduced plasma HIV RNA levels by a median of 1.77 log in viremic participants, with a viral load nadir at a median of 8.5 days. Two individuals with low baseline viral loads experienced ART-free viral suppression for ≥168 days following antibody infusion, and rebound viruses in these individuals demonstrated full or partial PGT121 sensitivity. The trial met the prespecified endpoints. These data suggest that further investigation of the potential of antibody-based therapeutic strategies for long-term suppression of HIV is warranted, including in individuals off ART and with low viral load.
Subject(s)
Antiviral Agents/administration & dosage , Broadly Neutralizing Antibodies/administration & dosage , HIV Infections/drug therapy , HIV-1/drug effects , Adult , Antiretroviral Therapy, Highly Active , Antiviral Agents/immunology , Antiviral Agents/pharmacokinetics , Broadly Neutralizing Antibodies/immunology , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/virology , Double-Blind Method , Female , HIV Envelope Protein gp120/antagonists & inhibitors , HIV Envelope Protein gp120/immunology , HIV Infections/genetics , HIV Infections/pathology , HIV Infections/virology , HIV-1/pathogenicity , Humans , Male , Middle Aged , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/immunology , Placebos , Viral Load/drug effects , Viral Load/immunology , Young AdultABSTRACT
Three undescribed hydroxycinnamic acid amide dimers 1-3 were isolated and identified from an extract of Goji berry. Their molecular structures were elucidated based on NMR, MS, and IR spectra analysis. Compounds 1-3 were hydroxycinnamic acid amide dimers, which possess a cyclic butane moiety formed by head-to-head connection. These compounds at 25â µM showed the disaggregation potency on the copper-mediated Aß1-42 aggregation ranging from 27.3±3.2 to 31.0±2.9 %. This study provides new information on the antiaging traditional usage of goji berry.
Subject(s)
Alzheimer Disease/drug therapy , Amides/pharmacology , Coumaric Acids/pharmacology , Lycium/chemistry , Neuroprotective Agents/pharmacology , Plant Extracts/pharmacology , Alzheimer Disease/metabolism , Amides/chemistry , Amides/isolation & purification , Amyloid beta-Peptides/antagonists & inhibitors , Amyloid beta-Peptides/metabolism , Coumaric Acids/chemistry , Coumaric Acids/isolation & purification , Dose-Response Relationship, Drug , Humans , Molecular Conformation , Neuroprotective Agents/chemistry , Neuroprotective Agents/isolation & purification , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/metabolism , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Protein Aggregates/drug effectsABSTRACT
Alzheimer's disease (AD) is a severe multifactorial neurodegenerative disorder characterized by a progressive loss of neurons in the brain. Despite research efforts, the pathogenesis and mechanism of AD progression are not yet completely understood. There are only a few symptomatic drugs approved for the treatment of AD. The multifactorial character of AD suggests that it is important to develop molecules able to target the numerous pathological mechanisms associated with the disease. Thus, in the context of the worldwide recognized interest of multifunctional ligand therapy, we report herein the synthesis, characterization, physicochemical and biological evaluation of a set of five (1a-e) new ferulic acid-based hybrid compounds, namely feroyl-benzyloxyamidic derivatives enclosing different substituent groups, as potential anti-Alzheimer's disease agents. These hybrids can keep both the radical scavenging activity and metal chelation capacity of the naturally occurring ferulic acid scaffold, presenting also good/mild capacity for inhibition of self-Aß aggregation and fairly good inhibition of Cu-induced Aß aggregation. The predicted pharmacokinetic properties point towards good absorption, comparable to known oral drugs.
Subject(s)
Alzheimer Disease/drug therapy , Antioxidants/therapeutic use , Coumaric Acids/therapeutic use , Amyloid beta-Peptides/antagonists & inhibitors , Antioxidants/chemistry , Computer Simulation , Coumaric Acids/chemistry , Humans , Hydroxylamines/chemistry , Hydroxylamines/therapeutic use , Peptide Fragments/antagonists & inhibitors , Structure-Activity RelationshipABSTRACT
Histone acetyltransferases (HATs) play a crucial role in post-translational modification. Among them, overexpression, mutation, or hyperfunction of EP300/CBP has been associated with various cancers. In this study, we identified the novel compound 2-chloro-5-[5-[(E)-[1-(3-chlorophenyl)-3-methyl-5-oxo-pyrazol-4-ylidene]methyl]-2-furyl]benzoic acid (1) as an EP300 HAT inhibitor via virtual screening. Further research has been focused on the design, synthesis, and in vitro biological evaluation of virtual hit derivatives. The studies revealed that 4-pyridone-3-carboxylic acid derivatives exhibited bioisosterism of benzoic acid. Replacement proved effective, providing compounds with similar EP300 HAT-inhibitory activity and improved cell growth-inhibitory activity compared to the benzoic acid analogs. Through these studies, we identified a potent and selective EP300/CBP HAT inhibitor.