Search

A series of 4-amino Capsaicin analogs 15, 17 and 19 were prepared to investigate the bioisosteric effect of 4-amino group, and all these compounds exhibited moderate or weak potency from their analgesic test. From our previous results and others, 4-hydroxyl group, as well as 3-methoxy substituent could be crucial for high analgesic activity. This biological result also shows that the activity is sensitive to alkyl chain length in hydrophobic region and the phenylacetic amides 19 are more active than the corresponding urea derivatives 17. [ABSTRACT FROM AUTHOR]

The present study was undertaken to determine the inhibitory effects of orally adminstered ginseng saponins(GS), protopanaxadiol saponins(PD), protopanaxatriol saponins(PT) and ginseng ether fraction(GE) on the development of morphine induced tolerance and physical dependence in mice and also to determine the hepatic glutathione contents. GS, PD and PT inhibited significantly the development of morphine induced tolerance and physical dependence, but GE was effective only on the inhibition of the development of morphine induced physical dependence. GS, PD, PT and GE also inhibited the hepatic glutathione level decrease induced by morphine multiple injections. [ABSTRACT FROM AUTHOR]

Abstract: In the continuing search for novel compounds targeting serotonin 5-HT2A, 5-HT2C, and serotonin transporter, new arylpiperazine-containing pyrrole 3-carboxamide derivatives were synthesized and evaluated. Based on the lead reported previously, structural modifications regarding N-(3-(4-(2,3-dichlorophenyl)piperazin-1-yl)propyl)-1,2-dimethyl-5-phenyl-1H-pyrrole-3-carboxamide 5, were accomplished for improvements in not only binding affinity against serotonin receptors and transporter, but also in hERG channel inhibition. Along the line, both the forced swimming tests and spontaneous locomotor activity tests were performed to distinguish between antidepressant activity and false positive results. As potential antidepressant agents, both 2,4-dimethyl-5-phenyl-1H-pyrrole-3-carboxamide and 5-tert-butyl-2-methyl-1H-pyrrole-3-carboxamide derivatives exhibited favorable in vitro and in vivo activities, warranting further investigation around these scaffolds. [ABSTRACT FROM AUTHOR]

TREK-1 (TWIK-related potassium channel-1) is a subunit of the two-pore domain potassium (K2p) channel and is widely expressed in the brain. TREK-1 knockout mice were shown to have antidepressant-like effects, providing evidence for the channel's potential as a therapeutic target. However, currently there is no good pharmacological inhibitor specifically targeting TREK-1 containing K2p channels that also displays similar antidepressant-like effects. Here, we sought to find selective and potent inhibitors for TREK-1 related dimers both in vitro and in vivo. We synthesized and evaluated 2-hydroxy-3-phenoxypropyl piperidine derivatives yielding a library from which many TREK-1 targeting candidates emerged. Among these, hydroxyl-phenyl- (2a), piperidino- (2g), and pyrrolidino- (2h) piperidinyl substituted compounds showed high potencies to TREK-1 homodimers with significant antidepressant-like effects in forced swim test and tail suspension test. Interestingly, these compounds were found to have high potencies to TWIK-1/TREK-1 heterodimers. Contrastingly, difluoropiperidinyl-4-fluorophenoxy (3e) and 4-hydroxyphenyl-piperidinyl-4-fluorophenoxy (3j) compounds had high potencies to TREK-1 homodimer but lower potency to TWIK-1/TREK-1 heterodimers without significant antidepressant-like effects. We observed positive correlation between inhibition potency to TWIK-1/TREK-1 and immobility time, and no correlation between inhibition potency to TREK-1 homodimer and immobility time. This was consistent with molecular docking simulations of selected compounds to TREK-1 homodimeric and TWIK-1/TREK-1 heterodimeric models. Existing antidepressant fluoxetine was also found to potently inhibit TWIK-1/TREK-1 heterodimers. Our study reveals novel potent TWIK-1/TREK-1 inhibitors 2a, 2g, and 2h as potential antidepressants and suggest that the TWIK-1/TREK-1 heterodimer could be a potential novel molecular therapeutic target for antidepressants., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Stress is an overwhelming problem associated with neuronal damage leading to anxiety and depression. The compound 3, 4, 5-trimethoxycinnamic acid (TMCA) has shown anti-stress effects; however, its derivatives remained unknown for their anxiolytic properties. Here, therefore, we investigated derivatives of TMCA (dTMCA) for their anxiolytic effects using immobilization and electric shock-induced stress in rats. Derivatives of TMCA ameliorated anxiety in mice and rats revealed by extended period of time spent in the open arms of elevated plus maze. Stress-mediated repression of tyrosine hydroxylase (TH) protein expression in the amygdala regions of rat brain and dopamine levels in the PC12 cells was restored by two selected derivatives (TMCA#5 and TMCA#9). Unlike TH expression, stress-induced protein expression of phospho-extracellular signal-regulated kinase (pERK) was unaffected by both derivatives in rats. Given the preferential inhibitory activity of dTMCA on dopamine and serotonin receptors, serotonergic road map of cellular signaling could be their target for anxiolytic effects. Thus, dTMCA would be promising agents to prevent neuronal damage associated with rampant stressful conditions., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Interleukin-1 receptor-associated kinase 4 (IRAK4) is a pivotal enzyme in the Toll-like receptor (TLR)/MYD88 dependent signaling pathway, which is highly activated in rheumatoid arthritis tissues and activated B cell-like diffuse large B-cell lymphoma (ABC-DLBCL). Inflammatory responses followed by IRAK4 activation promote B-cell proliferation and aggressiveness of lymphoma. Moreover, proviral integration site for Moloney murine leukemia virus 1 (PIM1) functions as an anti-apoptotic kinase in propagation of ABC-DLBCL with ibrutinib resistance. We developed a dual IRAK4/PIM1 inhibitor KIC-0101 that potently suppresses the NF- κ B pathway and proinflammatory cytokine induction in vitro and in vivo . In rheumatoid arthritis mouse models, treatment with KIC-0101 significantly ameliorated cartilage damage and inflammation. KIC-0101 inhibited the nuclear translocation of NF- κ B and activation of JAK/STAT pathway in ABC-DLBCLs. In addition, KIC-0101 exhibited an anti-tumor effect on ibrutinib-resistant cells by synergistic dual suppression of TLR/MYD88-mediated NF- κ B pathway and PIM1 kinase. Our results suggest that KIC-0101 is a promising drug candidate for autoimmune diseases and ibrutinib-resistant B-cell lymphomas., Competing Interests: The authors declare no conflicts of interest., (© 2022 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.)

Direct inhibitors of glycogen synthase kinase 3β (GSK3β) have been investigated and reported for the past 20 years. In the search for novel scaffold inhibitors, 3000 compounds were selected through structure-based virtual screening (SBVS), and then high-throughput enzyme screening was performed. Among the active hit compounds, pyrazolo [1,5-a]pyrimidin-7-amine derivatives showed strong inhibitory potencies on the GSK3β enzyme and markedly activated Wnt signaling. The result of the molecular dynamics (MD) simulation, enhanced by the upper-wall restraint, was used as an advanced structural query for the SBVS. In this study, strong inhibitors designed to inhibit the GSK3β enzyme were discovered through SBVS. Our study provides structural insights into the binding mode of the inhibitors for further lead optimization.

Recovery of mitochondrial dysfunction has gained increasing attention as an alternative therapeutic strategy for Alzheimer's disease (AD). Recent studies suggested that the 18 kDa mitochondrial translocator protein (TSPO) has the potential to serve as a drug target for the treatment of AD. In this study, we generated a structure-based pharmacophore model and virtually screened a commercial library, identifying SVH07 as a virtual hit, which contained a tricyclic core structure, thieno[2',3':4,5]pyrrolo[1,2-d][1,2,4]triazine group. A series of SVH07 analogues were synthesized and their effects on the mitochondrial membrane potential and ATP production were determined by using neuronal cells under Aβ-induced toxicity. Among these analogues, compound 26 significantly recovered mitochondrial membrane depolarization and ATP production. In vitro binding assays indicated that SVH07 and 26 showed high affinities to TSPO with the IC 50 values in a nanomolar range. We believe that compound 26 is a promising lead compound for the development of TSPO-targeted mitochondrial functional modulators with therapeutic potential in AD., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Translocator protein (TSPO) is involved in modulating mitochondrial permeability transition pore (mPTP) opening/closure leading to either apoptotic cell death via opening of mPTP or cell protection mediated by mPTP blocking and hence intercepting mPTP induced apoptosis. Herein, 2-(2-aryloxyphenyl)-1,4-dihydroisoquinolin-3(2H)-one derivatives have been designed and synthesized as new modulators for amyloid-β-induced mPTP opening. Among all, compound 7c remarkably enhanced mPTP opening while compound 7e showed the highest mPTP blocking activity. Molecular modelling study revealed different binding modes which might underlie the observed opposing biological activities. Both compounds bound to the translocator protein 18kDa (TSPO) in low micromolar range and elicited good profiles on CYP2D6 and CYP1A2. Taken as a whole, this report presents compound 7e as a hit TSPO ligand for treatment of neurodegenerative diseases and compound 7c as a hit TSPO ligand for promoting cell death of cells over-expressing TSPO., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Herein, we report new quinazoline-urea based compounds with potent cytotoxic activities against TMZ-resistant glioblastoma multiforme (GBM) cells. Low micromolar IC₅₀ values were exhibited over a panel of three primary GBM patient-derived cell cultures belonging to proneural (GBM-1), mesenchymal (GBM-2), and classical (GBM-3) subtypes. Eight compounds showed excellent selectivity indices for GBM cells comparing to a normal astrocyte cell line. In JC-1 assay, analogues 11, 12, 20, 22, and 24 exerted promising rates of mPTP opening induction towards proneural GBM subtype. Compounds 11, 20, and 24 bound to the translocator protein 18 kDa (TSPO) in submicromolar range using [(3)H] PK-11195 binding affinity assay. A homology model was built and docked models of 11, 12, 20, 22 and 24 were generated for describing their plausible binding modes in TSPO. In 3D clonogenic assay, compound 20 manifested potent tumoricidal effects on TMZ-resistant GBM cells even at submicromolar concentrations. In addition, CYP450 and hERG assays presented a safe toxicity profile of 20. Taken as a whole, this report presents compound 20 as a potent, selective and safe GBM cytotoxic agent which constitutes a promising direction against TMZ-resistant GBM., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Neuregulin 1 (NRG1) is a trophic factor that is thought to have important roles in the regulating brain circuitry. Recent studies suggest that NRG1 regulates synaptic transmission, although the precise mechanisms remain unknown. Here we report that NRG1 influences glutamate uptake by increasing the protein level of excitatory amino acid carrier (EAAC1). Our data indicate that NRG1 induced the up-regulation of EAAC1 in primary cortical neurons with an increase in glutamate uptake. These in vitro results were corroborated in the prefrontal cortex (PFC) of mice given NRG1. The stimulatory effect of NRG1 was blocked by inhibition of the NRG1 receptor ErbB4. The suppressed expression of ErbB4 by siRNA led to a decrease in the expression of EAAC1. In addition, the ablation of ErbB4 in parvalbumin (PV)-positive neurons in PV-ErbB4(-/-) mice suppressed EAAC1 expression. Taken together, our results show that NRG1 signaling through ErbB4 modulates EAAC1. These findings link proposed effectors in schizophrenia: NRG1/ErbB4 signaling perturbation, EAAC1 deficit, and neurotransmission dysfunction., (© 2015 by The American Society for Biochemistry and Molecular Biology, Inc.)

Even though nicotinic acid (niacin) appears to have beneficial effects on human lipid profiles, niacin-induced cutaneous vasodilatation called flushing limits its remedy to patient. GPR109A is activated by niacin and mediates the anti-lipolytic effects. Based on the hypothesis that β-arrestin signaling mediates niacin-induced flushing, but not its anti-lipolytic effect, we tried to find GPR109A agonists which selectively elicit Gi-protein-biased signaling devoid of β-arrestin internalization using a β-lactamase assay. We identified a 4-(phenyl)thio-1H-pyrazole as a novel scaffold for GPR109A agonist in a high throughput screen, which has no carboxylic acid moiety known to be important for binding. While 1-nicotinoyl derivatives (5a-g, 6a-e) induced β-arrestin recruitment, 1-(pyrazin-2-oyl) derivatives were found to play as G-protein-biased agonists without GPR109A receptor internalization. The activity of compound 5a (EC50 = 45 nM) was similar to niacin (EC50 = 52 nM) and MK-6892 (EC50 = 74 nM) on calcium mobilization assay, but its activity at 10 μM on β-arrestin recruitment were around two and five times weaker than niacin and MK-6892, respectively. The development of G-protein biased GPR109A ligands over β-arrestin pathway is attainable and might be important in differentiation of pharmacological efficacy.

A novel series of 4-nitroindole sulfonamides containing a methyleneamino-N,N-dimethylformamidine were prepared. The binding of these compounds to 5-HT2A and 5-HT2C was evaluated, and most of the compounds showed IC50 values of less than 1μM, and exhibited high selectivity for the 5-HT2C receptor. However, little selectivity was observed in the functional assay for 5-HT6 receptors. The computational modeling studies further validated the biological results and also demonstrated a reasonable correlation between the activity of compounds and the mode of superimposition with specified pharmacophoric features., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

5-HT7 receptor (5-HT7R) is a promising target for the treatment of depression and neuropathic pain. 5-HT7R antagonists exhibited antidepressant effects, while the agonists produced strong anti-hyperalgesic effects. In our efforts to discover selective 5-HT7R antagonists or agonists, N-biphenylylmethyl 2-methoxyphenylpiperazinylalkanamides 1 were designed, synthesized, and biologically evaluated against 5-HT7R. Among the synthesized compounds, N-2'-chlorobiphenylylmethyl 2-methoxyphenylpiperazinylpentanamide 1-8 showed the best binding affinity with a Ki value of 8.69nM and it was verified as a novel antagonist according to functional assays. The compound 1-8 was very selective over 5-HT1DR, 5-HT2AR, 5-HT3R, 5-HT5AR and 5-HT6R and moderately selective over 5-HT1AR, 5-HT1BR and 5-HT2CR. The novel 5-HT7R antagonist 1-8 exhibited an antidepressant effect at a dose of 25mg/kg in the forced swimming test in mice and showed a U-shaped dose-response curve which typically appears in 5-HT7R antagonists such as SB-269970 and lurasidone., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The interaction of stem cell factor (SCF) with its cognate receptor c-Kit is closely associated with the survival and maturation of melanocytes. To investigate novel depigmentation agents, we screened 2,000 plant extracts for c-Kit inhibitors to identify active small molecules by using time-resolved fluorescence enzyme assays. For the active extracts identified as inhibitors of c-Kit enzyme, we evaluated the effects of the active extracts and isolated flavonoids on c-Kit phosphorylation in MO7e/melanocytes. Anti-melanogenic activity was also examined in melanocytes and melanoderm model. The flavonoids such as diosmetin, apigenin, acacetin and luteolin isolated from Chrysanthemum morifolium were found to be active in inhibiting c-Kit both at enzyme and cellular levels. In addition, these flavonoids attenuated SCF-induced proliferation of human primary melanocytes without toxicity and suppressed ultraviolet (UV) B irradiation-mediated melanin synthesis significantly. Among the active flavonoids, diosmetin was found to inhibit SCF-induced melanogenesis in a human melanoderm model. These results strongly suggest that C. morifolium extract and diosmetin have potential to suppress SCF-/UVB-induced melanogenesis, and could be developed as anti-pigmentation agents.

Obesity is one of the most serious public health problems worldwide in the 21st century. Current therapeutic treatment for obesity is mostly focused on preventive measures involving dietary control and physical exercises in combination with anti-obesity medications. However, most of these anti-obesity medications have little or no effect on weight loss, and some cases have demonstrated fatal side effects. Due to the urgent need for highly potent and selective anti-obesity agents, the serotonin receptors (5-HTR) have been the focus of much interest as a novel therapeutic target. In this report, we have developed pyrimidoazepine analogs targeting the 5-HT2A and 5-HT2C receptors and evaluated their biological activity in vitro and in vivo as novel anti-obesity agents. We were able to identify 6p as the most potent 5-HT2A and 5-HT2C ligand in vitro (IC50 = 3 nM and 2.3 nM, respectively), and this compound also demonstrated the greatest potency in vivo. In an acute obesity model, mice treated with 6p showed significant decrease in body weight gain and food intake over approximately 77-94% compared to a control group. In a chronic obesity model, mice treated with 6p also showed a marked decrease in food intake and body weight gain., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Abnormal accumulation of β-amyloid (Aβ) is the main characteristic of Alzheimer's disease (AD) brain and Aβ peptides are generated from proteolytic cleavages of amyloid precursor protein (APP) by β-site APP-converting enzyme 1 (BACE1) and presenilin 1 (PS1). Sphingosylphosphorylcholine (SPC), a choline-containing sphingolipid, showed suppressive effect on Aβ production in PC12 cells which stably express Swedish mutant of amyloid precursor protein (APPsw). SPC (> 3 μM) significantly lowered the accumulation of Aβ40/42 and the expression of BACE1. However, the transcriptions of other APP processing enzymes like ADAM10 and PS1 were not affected by the SPC addition. Meanwhile, phosphocholine (PC) or other lysophospholipids, such as lysophosphatidylcholine (LPC), lysophosphatidic acid (LPA), sphingosyl-1-phosphate (S1P), did not alter BACE1 expression. Down-regulatory effect of SPC on BACE1 expression appeared to be mediated by NF-κB which is known to suppress the trans-activation of BACE1 promoter in PC12 cells. Here, the nuclear tanslocation of NF-κB was enhanced by SPC treatment in immune-fluorescent image analysis and NF-κB reporter assay. Furthermore, the catalytic activities of BACE1 and BACE2 were dose-dependently inhibited by SPC displaying IC₅₀ values of 2.79 μM and 12.05 μM, respectively. Overall, these data suggest that SPC has the potential to ameliorate Aβ pathology in neurons by down-regulating the BACE1-mediated amyloidogenic pathway.

A new resveratrol oligomer (1) together with eight related components (2- 9) were isolated from the seed extract of Paeonia lactiflora (Paeoniaceae) as active principles responsible for the inhibition of beta-site APP-cleaving enzyme 1 (BACE-1) in vitro. The chemical structure of 1 was established as (-)-7a,8a- CIS- ε-viniferin with the aid of spectroscopic analyses including NOESY experiments. All isolated resveratrol oligomers (1- 9) demonstrated significant inhibition on baculovirus-expressed BACE-1 in a dose-dependent manner, which was assessed by the FRET assay using Rh-EVNLDAEFK as a substrate in vitro., (© Georg Thieme Verlag KG Stuttgart · New York.)

A novel series of 5-HT(2A) ligands that contain a (phenylpiperazinyl-propyl)arylsulfonamides skeleton was synthesized. Thirty-seven N-(cycloalkylmethyl)-4-methoxy-N-(3-(4-arylpiperazin-1-yl)propyl)-arylsulfonamide and N-(4-(4-arylpiperazin-1-yl)butan-2-yl)-arylsulfonamide compounds were obtained. The binding of these compounds to the 5-HT(2A), 5-HT(2C), and 5-HT(7) receptors was evaluated. Most of the compounds showed IC(50) values of less than 100 nM and exhibited high selectivity for the 5-HT(2A) receptor. Among the synthesized compounds, 16a and 16d showed good affinity at 5-HT(2A) (IC(50)=0.7 nM and 0.5 nM) and good selectivity over 5-HT(2C) (50-100 times) and 5-HT(7) (1500-3000 times)., (Copyright 2010 Elsevier Ltd. All rights reserved.)

A new isoflavone, neocorylin ( 1) was isolated from the seeds extract of Psoralea corylifolia L. (Fabaceae), together with eight known constituents ( 2 - 9), i. e., bakuchiol ( 2), psoralen ( 3), bavachromene ( 4), isobavachromene ( 5), bavachalcone ( 6), isobavachalcone ( 7), 7,8-dihydro-8-(4-hydrophenyl)-2,2-dimethyl-2 H,6 H-[1,2- B:5,4- B']dipyran-6-one ( 8), and bavachinin ( 9). The structure of the new isoflavone 1 was elucidated as 7-hydroxy-3-[2-methyl-2-(4-methylpenten-3-yl)-2 H-chromen-6-yl]-4 H-chromen-4-one by spectroscopic analyses. Neocorylin ( 1) as well as related compounds 2, 4 - 6, 8 and 9 exhibited a significant inhibitory effect on baculovirus-expressed BACE-1 in vitro.

Serotonin 5-HT6 receptor antagonists are thought to play an important role in the treatment of psychiatry, Alzheimer's disease, and probably obesity. To find novel and potent 5-HT6 antagonists and to provide a new idea for drug design, we used a ligand-based pharmacophore to perform the virtual screening of a commercially available database. A three-dimensional common feature pharmacophore model was developed by using the HipHop program provided in Catalyst software and was used as a query for screening the database. A recursive partitioning (RP) model which can separate active and inactive compounds was used as a filtering system. Finally a sequential virtual screening procedure (SQSP) was conducted, wherein both the common feature pharmacophore and the RP model were used in succession to improve the results. Some of the hits were selected based on druglikeness, ADME properties, structural diversity, and synthetic accessibility for real biological evaluation. The best hit compound showed a significant IC50 value of 9.6 nM and can be used as a lead for further drug development.