scholarly journals Tetrahydrocurcumin Has Similar Anti-Amyloid Properties as Curcumin:  In Vitro Comparative Structure-Activity Studies

Antioxidants ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1592
Author(s):  
Panchanan Maiti ◽  
Jayeeta Manna ◽  
Joshua Thammathong ◽  
Bobbi Evans ◽  
Kshatresh Dutta Dubey ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Similar Degree ◽  
Amyloid Beta Protein ◽  
Dot Blot ◽  
Neuroprotective Effects ◽  
Transmission Electron ◽  
Aβ Aggregation ◽  
Comparative Structure ◽  
Aggregation Inhibition

Despite its potent anti-amyloid properties, the utility of curcumin (Cur) for the treatment of Alzheimer’s disease (AD) is limited due to its low bioavailability. Tetrahydrocurcumin (THC), a more stable metabolite has been found in Cur-treated tissues. We compared the anti-amyloid and neuroprotective properties of curcumin, bisdemethoxycurcumin (BDMC), demethoxycurcumin (DMC) and THC using molecular docking/dynamics, in-silico and in vitro studies. We measured the binding affinity, H-bonding capabilities of these compounds with amyloid beta protein (Aβ). Dot blot assays, photo-induced cross linking of unmodified protein (PICUP) and transmission electron microscopy (TEM) were performed to monitor the Aβ aggregation inhibition using these compounds. Neuroprotective effects of these derivatives were evaluated in N2a, CHO and SH-SY5Y cells using Aβ42 (10 µM) as a toxin. Finally, Aβ-binding capabilities were compared in the brain tissue derived from the 5× FAD mouse model of AD. We observed that THC had similar binding capability and Aβ aggregation inhibition such as keto/enol Cur and it was greater than BDMC and DMC. All these derivatives showed a similar degree of neuroprotection in vitro and labeled Aβ-plaques ex vivo. Overall, ECur and THC showed greater anti-amyloid properties than other derivatives. Therefore, THC, a more stable and bioavailable metabolite may provide greater therapeutic efficacy in AD than other turmeric derivatives.

Exploring the potential of pyrazoline containing molecules as Aβ aggregation inhibitors in Alzheimer’s disease

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Mihir Pramod Khambete ◽  
Lalit Pramod Khare ◽  
Akshay Bhupendra Kapadia ◽  
Mariam Sohel Degani
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cd Spectroscopy ◽  
Aromatic Rings ◽  
Transmission Electron ◽  
Aβ Aggregation ◽  
Aggregation Inhibitors ◽  
Aggregation Inhibition ◽  
Amyloid Aβ

AbstractObjectivesAlzheimer’s disease (AD) is a chronic and progressive neurodegenerative disease in which one of the most prominent pathological features is accumulation of amyloid (Aβ) plaques. This occurs due to the process of aggregation from monomeric to polymeric forms of Aβ peptide and thus represents one of the attractive targets to treat AD.MethodsAfter initial evaluation of a set of molecules containing N-acetylpyrazoline moiety flanked by aromatic rings on both sides as Aβ aggregation inhibitors, the most potent molecules were further investigated for mechanistic insights. These were carried out by employing techniques such as circular dichroism (CD) spectroscopy, transmission electron microscopy (TEM), in vitro PAMPA-BBB (Blood–Brain Barrier) assay and cytotoxicity evaluation.ResultsTwo molecules among the exploratory set displayed Aβ aggregation inhibition comparable to standard curcumin. Among the follow-up molecules, several molecules displayed more inhibition than curcumin. These molecules displayed good inhibitory activity even at lower concentrations. CD and TEM confirmed the mechanism of Aβ aggregation. These molecules were found to alleviate Aβ induced cytotoxicity. BBB penetration studies highlighted the potential of these molecules to reach central nervous system (CNS).ConclusionsThus, several promising Aβ-aggregation inhibitors were obtained as a result of this study.

scholarly journals Design and Development of Multi-target Directed 1,2,3-rriazole-dimethylaminoacryloyl-chromenone Derivatives with Potential use in Alzheimer's Disease

2020 ◽  
Author(s):  
Hajar Karimi Askarani ◽  
Aida Iraji ◽  
Arezoo Rastegari ◽  
Syed Nasir Abbas Bukhari ◽  
Omidreza Firuzi ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Biological Activities ◽  
Neuroprotective Effects ◽  
Catalytic Active Site ◽  
Aβ Aggregation ◽  
Aggregation Inhibition ◽  
Multifunctional Agents ◽  
Potential Use

Abstract To discover multifunctional agents for the treatment of Alzheimer's disease (AD), a new series of 1,2,3-triazole-chromenone derivatives were designed and synthesized based on the multi target-directed ligands approach. The in vitro biological activities were evaluated including acetylcholinesterase (AChE), butylcholinesterase (BuChE), and Aβ1−42 aggregation inhibition as well as neuroprotective effects and metal-chelating properties. The results indicated highly selective BuChE inhibitory activity with IC50 values of 21.71 µM for compound 10 h as the most potent compound. Besides, compound 10 h could inhibit self-induced Aβ1−42 aggregation and AChE-induced Aβ aggregation with 32.6% and 29.4% inhibition value, respectively. A Lineweaver–Burk plot and molecular modeling study also showed that compound 10 h targeted both the catalytic active site (CAS) and peripheral anionic site (PAS) of BuChE. It should be noted that compound 10 h was potent as a selective Cu2+ chelator. Thus, the designed scaffold could be considered as multifunctional agents for AD drug discovery developments.

scholarly journals Design and synthesis of multi-target directed 1,2,3-triazole-dimethylaminoacryloyl-chromenone derivatives with potential use in Alzheimer's disease

BMC Chemistry ◽  
2020 ◽  
Vol 14 (1) ◽  
Author(s):  
Hajar Karimi Askarani ◽  
Aida Iraji ◽  
Arezoo Rastegari ◽  
Syed Nasir Abbas Bukhari ◽  
Omidreza Firuzi ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Biological Activities ◽  
Neuroprotective Effects ◽  
Design And Synthesis ◽  
Catalytic Active Site ◽  
Aβ Aggregation ◽  
Multifunctional Agents ◽  
Potential Use

Abstract To discover multifunctional agents for the treatment of Alzheimer's disease (AD), a new series of 1,2,3-triazole-chromenone derivatives were designed and synthesized based on the multi target-directed ligands approach. The in vitro biological activities included acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibition as well as anti-Aβ aggregation, neuroprotective effects, and metal-chelating properties. The results indicated a highly selective BuChE inhibitory activity with an IC50 value of 21.71 μM for compound 10h as the most potent compound. Besides, compound 10h could inhibit self-induced Aβ1–42 aggregation and AChE-induced Aβ aggregation with 32.6% and 29.4% inhibition values, respectively. The Lineweaver–Burk plot and molecular modeling study showed that compound 10h targeted both the catalytic active site (CAS) and peripheral anionic site (PAS) of BuChE. It should be noted that compound 10h was able to chelate biometals. Thus, the designed scaffold could be considered as multifunctional agents in AD drug discovery developments.

scholarly journals 9-Methylfascaplysin Is a More Potent Aβ Aggregation Inhibitor than the Marine-Derived Alkaloid, Fascaplysin, and Produces Nanomolar Neuroprotective Effects in SH-SY5Y Cells

Marine Drugs ◽  
2019 ◽  
Vol 17 (2) ◽  
pp. 121 ◽  
Author(s):  
Qingmei Sun ◽  
Fufeng Liu ◽  
Jingcheng Sang ◽  
Miaoman Lin ◽  
Jiale Ma ◽  
...  
Keyword(s):  
Amino Acid Residues ◽  
Neuroprotective Effects ◽  
Study Results ◽  
Aβ Aggregation ◽  
Aggregation Inhibitors ◽  
Amyloid Aβ ◽  
Β Amyloid ◽  
Dynamics Simulations ◽  
Aβ Oligomer

β-Amyloid (Aβ) is regarded as an important pathogenic target for Alzheimer’s disease (AD), the most prevalent neurodegenerative disease. Aβ can assemble into oligomers and fibrils, and produce neurotoxicity. Therefore, Aβ aggregation inhibitors may have anti-AD therapeutic efficacies. It was found, here, that the marine-derived alkaloid, fascaplysin, inhibits Aβ fibrillization in vitro. Moreover, the new analogue, 9-methylfascaplysin, was designed and synthesized from 5-methyltryptamine. Interestingly, 9-methylfascaplysin is a more potent inhibitor of Aβ fibril formation than fascaplysin. Incubation of 9-methylfascaplysin with Aβ directly reduced Aβ oligomer formation. Molecular dynamics simulations revealed that 9-methylfascaplysin might interact with negatively charged residues of Aβ42 with polar binding energy. Hydrogen bonds and π–π interactions between the key amino acid residues of Aβ42 and 9-methylfascaplysin were also suggested. Most importantly, compared with the typical Aβ oligomer, Aβ modified by nanomolar 9-methylfascaplysin produced less neuronal toxicity in SH-SY5Y cells. 9-Methylfascaplysin appears to be one of the most potent marine-derived compounds that produces anti-Aβ neuroprotective effects. Given previous reports that fascaplysin inhibits acetylcholinesterase and induces P-glycoprotein, the current study results suggest that fascaplysin derivatives can be developed as novel anti-AD drugs that possibly act via inhibition of Aβ aggregation along with other target mechanisms.

scholarly journals Antioxidant and Neuroprotective Effects Induced by Cannabidiol and Cannabigerol in Rat CTX-TNA2 Astrocytes and Isolated Cortexes

2020 ◽  
Vol 21 (10) ◽  
pp. 3575 ◽  
Author(s):  
Viviana di Giacomo ◽  
Annalisa Chiavaroli ◽  
Lucia Recinella ◽  
Giustino Orlando ◽  
Amelia Cataldi ◽  
...  
Keyword(s):  
Kynurenic Acid ◽  
Cannabis Sativa ◽  
Ex Vivo ◽  
Neurological Diseases ◽  
Docking Studies ◽  
Experimental Models ◽  
Neuroprotective Effects ◽  
Rat Astrocytes ◽  
Species Production

Cannabidiol (CBD) and cannabigerol (CBG) are Cannabis sativa terpenophenols. Although CBD’s effectiveness against neurological diseases has already been demonstrated, nothing is known about CBG. Therefore, a comparison of the effects of these compounds was performed in two experimental models mimicking the oxidative stress and neurotoxicity occurring in neurological diseases. Rat astrocytes were exposed to hydrogen peroxide and cell viability, reactive oxygen species production and apoptosis occurrence were investigated. Cortexes were exposed to K+ 60 mM depolarizing stimulus and serotonin (5-HT) turnover, 3-hydroxykinurenine and kynurenic acid levels were measured. A proteomic analysis and bioinformatics and docking studies were performed. Both compounds exerted antioxidant effects in astrocytes and restored the cortex level of 5-HT depleted by neurotoxic stimuli, whereas sole CBD restored the basal levels of 3-hydroxykinurenine and kynurenic acid. CBG was less effective than CBD in restoring the levels of proteins involved in neurotransmitter exocytosis. Docking analyses predicted the inhibitory effects of these compounds towards the neurokinin B receptor. Conclusion: The results in the in vitro system suggest brain non-neuronal cells as a target in the treatment of oxidative conditions, whereas findings in the ex vivo system and docking analyses imply the potential roles of CBD and CBG as neuroprotective agents.

scholarly journals Targeting CDK5 in Astrocytes Promotes Calcium Homeostasis Under Excitotoxic Conditions

2021 ◽  
Vol 15 ◽  
Author(s):  
Luisa Fernanda Toro-Fernández ◽  
Juan Camilo Zuluaga-Monares ◽  
Ana María Saldarriaga-Cartagena ◽  
Gloria Patricia Cardona-Gómez ◽  
Rafael Posada-Duque
Keyword(s):  
Calcium Homeostasis ◽  
Calcium Influx ◽  
Ex Vivo ◽  
Hippocampal Slices ◽  
Glutamate Excitotoxicity ◽  
Neural Cells ◽  
Neuroprotective Effects ◽  
Hippocampal Area ◽  
Therapy Target

Glutamate excitotoxicity triggers overactivation of CDK5 and increases calcium influx in neural cells, which promotes dendritic retraction, spine loss, increased mitochondrial calcium from the endoplasmic reticulum, and neuronal death. Our previous studies showed that CDK5 knockdown (KD) in astrocytes improves neurovascular integrity and cognitive functions and exerts neuroprotective effects. However, how CDK5-targeted astrocytes affect calcium regulation and whether this phenomenon is associated with changes in neuronal plasticity have not yet been analyzed. In this study, CDK5 KD astrocytes transplanted in CA3 remained at the injection site without proliferation, regulated calcium in the CA1 hippocampal region after excitotoxicity by glutamate in ex vivo hippocampal slices, improving synapsin and PSD95 clustering. These CDK5 KD astrocytes induced astrocyte stellation and neuroprotection after excitotoxicity induced by glutamate in vitro. Also, these effects were supported by CDK5 inhibition (CDK5i) in vitro through intracellular stabilization of calcium levels in astrocytes. Additionally, these cells in cocultures restored calcium homeostasis in neurons, redistributing calcium from somas to dendrites, accompanied by dendrite branching, higher dendritic spines and synapsin-PSD95 clustering. In summary, induction of calcium homeostasis at the CA1 hippocampal area by CDK5 KD astrocytes transplanted in the CA3 area highlights the role of astrocytes as a cell therapy target due to CDK5-KD astrocyte-mediated synaptic clustering, calcium spreading regulation between both areas, and recovery of the intracellular astrocyte-neuron calcium imbalance and plasticity impairment generated by glutamate excitotoxicity.

scholarly journals Topical Delivery of Apremilast Loaded Nanostructured Lipid Carrier Based Hydrogel for Psoriasis Therapy

2021 ◽  
pp. 7-20
Author(s):  
S. M. Sindhoor ◽  
Marina Koland
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Extended Release ◽  
Ex Vivo ◽  
Entrapment Efficiency ◽  
Transmission Electron ◽  
Psoriasis Therapy ◽  
Systemic Side Effects

Background: Apremilast (APR) is an orally administered selective phosphodiesterase 4 inhibitor approved to treat plaque psoriasis and psoriatic arthritis and is available as an oral tablet formulation. However, its systemic side effects limit its application. The low solubility and permeability of apremilast make it difficult to administer it through the skin. Hence an attempt is made to incorporate apremilast into a suitable nanocarrier to facilitate its topical delivery. Aims: To formulate and characterize Apremilast loaded nanostructured lipid carriers for the management of psoriasis to reduce the systemic side effects. Methodology: Apremilast loaded Nanostructured Lipid carriers (NLC) were prepared by melt emulsification accompanied by probe sonication. The formulation was prepared using GMS, Sefsol 218, Tween 80 and Transcutol P as Solid Lipid, Liquid lipid, Surfactant and Penetration Enhancer. The NLC was incorporated into carbapol 934 dispersion to convert it into a gel. The NLC formulation was evaluated for size, Polydispersity Index, Zeta Potential, Entrapment efficiency,  Transmission Electron Microscopy. After that, the NLC gel was examined for Spreadability, Extrudabilty, Viscosity, In vitro drug release, Ex vivo permeation, Skin deposition and In vivo studies. Results: The formulated Apremilast loaded showed particle size of less than 200 nm (i.e.170.32nm) with a narrow PDI of 0.267. Entrapment efficiency revealed that 89.26±01.22% of the drug was entrapped. Transmission electron microscopy images confirmed the spherical nature of the nanocarrier. The extended-release pattern of the formulated NLC for 24h was observed in the in vitro release studies and followed the Higuchi model(R2=0.9966). Ex vivo permeability showed a 6.14 fold increase in permeability and 74.05±0.25% deposition of apremilast loaded NLC gel compared to apremilast gel. The formulation was stable for three months without significant changes. In vivo skin studies showed that the prepared NLC did not have any skin irritation potential. The antipsoriatic activity demonstrated by the Apremilast loaded NLC gel in the imiquimod induced psoriasis model in mice was comparable to the standard treatment. Conclusion: Apremilast loaded NLC demonstrated enhanced permeation, improved skin retention and extended-release compared to conventional gel. The developed formulation can be an alternative for psoriasis therapy after clinical trials in the future.

The effects of human umbilical cord perivascular cells on rat hepatocyte structure and functional polarity

2013 ◽  
Vol 91 (3) ◽  
pp. 140-147 ◽  
Author(s):  
Alejandro Gómez-Aristizábal ◽  
John Edward Davies
Keyword(s):  
Umbilical Cord ◽  
Ex Vivo ◽  
Human Umbilical Cord ◽  
Perivascular Cells ◽  
Transmission Electron ◽  
External Organization ◽  
Bioartificial Livers ◽  
Functional Polarization ◽  
Hepatocyte Growth

Hepatocyte culture is a useful tool for the study of their biology and the development of bioartificial livers. However, many challenges have to be overcome since hepatocytes rapidly lose their normal phenotype in vitro. We have recently demonstrated that human umbilical cord perivascular cells (HUCPVCs) are able to provide support to hepatocytes. In the present study we go further into exploring the effects that HUCPVCs have in the functional polarization, and both the internal and external organization, of hepatocytes. Also, we investigate HUCPVC–hepatocyte crosstalk by tracking both the effects of HUCPVCs on hepatocyte transcription factors and those of hepatocytes on the expression of hepatotrophic factors in HUCPVCs. Our results show that HUCPVCs maintain the functional polarity of hepatocytes ex vivo, as judged by the secretion of fluorescein into bile canaliculi, for at least 40 days. Transmission electron microscopy revealed that hepatocytes in coculture organize in an organoid-like structure embedded in extracellular matrix surrounded by HUCPVCs. In coculture, hepatocytes displayed a higher expression of C/EBPα, implicated in maintenance of the mature hepatocyte phenotype, and HUCPVCs upregulated hepatocyte growth factor and Jagged1 indicating that these genes may play important roles in HUCPVC–hepatocyte interactions.

scholarly journals Comparative in vitro and ex vivo activities of selected inhibitors of transthyretin aggregation: relevance in drug design

2007 ◽  
Vol 408 (1) ◽  
pp. 131-138 ◽  
Author(s):  
Isabel Cardoso ◽  
Maria Rosário Almeida ◽  
Nelson Ferreira ◽  
Gemma Arsequell ◽  
Gregorio Valencia ◽  
...  
Keyword(s):  
Benzoic Acid ◽  
Large Scale ◽  
Serum Proteins ◽  
Ex Vivo ◽  
In Vitro Assays ◽  
Screening Methods ◽  
Wild Type ◽  
Dot Blot ◽  
Amino Benzoic Acid

Destabilization of the tetrameric fold of TTR (transthyretin) is important for aggregation of the protein which culminates in amyloid fibril formation. Many TTR mutations interfere with tetramer stability, increasing the amyloidogenic potential of the protein. The vast majority of proposed TTR fibrillogenesis inhibitors are based on in vitro assays with isolated protein, limiting their future use in clinical assays. In the present study we investigated TTR fibrillogenesis inhibitors using a cellular system that produces TTR intermediates/aggregates in the medium. Plasmids carrying wild-type TTR, V30M or L55P cDNA were transfected into a rat Schwannoma cell line and TTR aggregates were investigated in the medium using a dot-blot filter assay followed by immunodetection. Results showed that, in 24 h, TTR L55P forms aggregates in the medium, whereas, up to 72 h, wild-type TTR and V30M do not. A series of 12 different compounds, described in the literature as in vitro TTR fibrillogenesis inhibitors, were tested for their ability to inhibit L55P aggregate formation; in this system, 2-[(3,5-dichlorophenyl) amino] benzoic acid, benzoxazole, 4-(3,5-difluorophenyl) benzoic acid and tri-iodophenol were the most effective inhibitors, as compared with the reference iododiflunisal, previously shown by ex vivo and in vitro procedures to stabilize TTR and inhibit fibrillogenesis. Among these drugs, 2-[(3,5-dichlorophenyl) amino] benzoic acid and tri-iodophenol stabilized TTR from heterozygotic carriers of V30M in the same ex vivo conditions as those used previously for iododiflunisal. The novel cellular-based test herein proposed for TTR fibrillogenesis inhibitor screens avoids not only lengthy and cumbersome large-scale protein isolation steps but also artefacts associated with most current in vitro first-line screening methods, such as those associated with acidic conditions and the absence of serum proteins.

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