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1.
Eur J Med Chem ; 265: 116042, 2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38141287

ABSTRACT

Dual-targeting anticancer agents 4-29 are designed by combining the structural features of purine-type microtubule-disrupting compounds and HDAC inhibitors. A library of the conjugate compounds connected by appropriate linkers was synthesized and found to possess HDACs inhibitory activity and render microtubule fragmentation by activating katanin, a microtubule-severing protein. Among various zinc-binding groups, hydroxamic acid shows the highest inhibitory activity of Class I HDACs, which was also reconfirmed by three-dimensional quantitative structure-activity relationship (3D-QSAR) pharmacophore prediction. The purine-hydroxamate conjugates exhibit enhanced cytotoxicity against MDA-MB231 breast cancer cells, H1975 lung cancer cells, and various clinical isolated non-small-cell lung cancer cells with different epidermal growth factor receptor (EGFR) status. Pyridyl substituents could be used to replace the C2 and N9 phenyl moieties in the purine-type scaffold, which can help to improve the solubility under physiological conditions, thus increasing cytotoxicity. In mice treated with the purine-hydroxamate conjugates, the tumor growth rate was significantly reduced without causing toxic effects. Our study demonstrates the potential of the dual-targeting purine-hydroxamate compounds for cancer monotherapy.


Subject(s)
Antineoplastic Agents , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Animals , Mice , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Cell Line, Tumor , Histone Deacetylases/metabolism , Antineoplastic Agents/chemistry , Histone Deacetylase Inhibitors/chemistry , Microtubules/metabolism , Purines/pharmacology , Hydroxamic Acids/chemistry , Structure-Activity Relationship , Cell Proliferation
2.
J Biomed Sci ; 30(1): 27, 2023 Apr 26.
Article in English | MEDLINE | ID: mdl-37101169

ABSTRACT

BACKGROUND: Amyotrophic lateral sclerosis (ALS) associated with TAR DNA-binding protein 43 (TDP-43) aggregation has been considered as a lethal and progressive motor neuron disease. Recent studies have shown that both C-terminal TDP-43 (C-TDP-43) aggregates and oligomers were neurotoxic and pathologic agents in ALS and frontotemporal lobar degeneration (FTLD). However, misfolding protein has long been considered as an undruggable target by applying conventional inhibitors, agonists, or antagonists. To provide this unmet medical need, we aim to degrade these misfolding proteins by designing a series of proteolysis targeting chimeras (PROTACs) against C-TDP-43. METHODS: By applying filter trap assay, western blotting, and microscopy imaging, the degradation efficiency of C-TDP-43 aggregates was studied in Neuro-2a cells overexpressing eGFP-C-TDP-43 or mCherry-C-TDP-43. The cell viability was characterized by alarmarBlue assay. The beneficial and disaggregating effects of TDP-43 PROTAC were examined with the YFP-C-TDP-43 transgenic C. elegans by motility assay and confocal microscopy. The impact of TDP-43 PROTAC on C-TDP-43 oligomeric intermediates was monitored by fluorescence lifetime imaging microscopy and size exclusion chromatography in the Neuro-2a cells co-expressing eGFP-C-TDP-43 and mCherry-C-TDP-43. RESULTS: Four PROTACs with different linker lengths were synthesized and characterized. Among these chimeras, PROTAC 2 decreased C-TDP-43 aggregates and relieved C-TDP-43-induced cytotoxicity in Neuro-2a cells without affecting endogenous TDP-43. We showed that PROTAC 2 bound to C-TDP-43 aggregates and E3 ligase to initiate ubiquitination and proteolytic degradation. By applying advanced microscopy, it was further shown that PROTAC 2 decreased the compactness and population of C-TDP-43 oligomers. In addition to cellular model, PROTAC 2 also improved the motility of transgenic C. elegans by reducing the C-TDP-43 aggregates in the nervous system. CONCLUSIONS: Our study demonstrated the dual-targeting capacity of the newly-designed PROTAC 2 against both C-TDP-43 aggregates and oligomers to reduce their neurotoxicity, which shed light on the potential drug development for ALS as well as other neurodegenerative diseases.


Subject(s)
Amyotrophic Lateral Sclerosis , Neurodegenerative Diseases , Animals , Amyotrophic Lateral Sclerosis/metabolism , Neurodegenerative Diseases/genetics , Proteolysis , Caenorhabditis elegans/genetics , Caenorhabditis elegans/metabolism , DNA-Binding Proteins/metabolism , Animals, Genetically Modified
3.
Carbohydr Res ; 521: 108662, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36099721

ABSTRACT

Polygonatum odoratum is a perennial rhizomatous medicinal plant and different plant parts have been used in the treatment of various ailments. Herein, we have investigated the structural compositions of rhizome, leaf, and stem cell walls. We found 30-44% of polysaccharides in these wall preparations were cyclohexanediaminetetraacetic acid (CDTA) extractable, the proportion of heteromannans (HMs) in the rhizome is nearly three-fold compared to that of the leave and stem. The pectic polysaccharides of the rhizome are also structurally more diverse, with arabinans and type I and type II arabinogalactans being richest as shown by linkage study of the sodium carbonate (Na2CO3) extract. In addition, the 2-linked Araf was rhizome-specific, suggesting the cell walls in the rhizome had adapted to a more complex structure compared to that of the leaf and stem. Water-soluble polysaccharide fractions were also investigated, high proportion of Man as in 4-linked Manp indicated high proportion of HMs. The 21.4 kDa pectic polysaccharides and HMs derived from rhizome cell walls induced specific immune response in mice macrophage cells producing IL-1α and hematopoietic growth factors GM-CSF and G-CSF in vitro.


Subject(s)
Polygonatum , Animals , Cell Wall , Granulocyte Colony-Stimulating Factor/analysis , Granulocyte-Macrophage Colony-Stimulating Factor/analysis , Mice , Plant Extracts/chemistry , Plant Leaves , Plants , Polygonatum/chemistry , Polysaccharides/analysis , Polysaccharides/pharmacology , Rhizome/chemistry , Water/analysis
4.
Front Chem ; 10: 947475, 2022.
Article in English | MEDLINE | ID: mdl-35910734

ABSTRACT

The extracellular human endo-6-O-sulfatases (Sulf-1 and Sulf-2) are responsible for the endolytic cleavage of the 6-sulfate groups from the internal D-glucosamine residues in the highly sulfated subdomains of heparan sulfate proteoglycans. A trisaccharide sulfate, IdoA2OS-GlcNS6S-IdoA2OS, was identified as the minimal size of substrate for Sulf-1. In order to study the complex structure with Sulf-1 for developing potential drugs, two trisaccharide analogs, IdoA2OS-GlcNS6OSO2NH2-IdoA2OS-OMe and IdoA2OS-GlcNS6NS-IdoA2OS-OMe, were rationally designed and synthesized as the Sulf-1 inhibitors with IC50 values at 0.27 and 4.6 µM, respectively.

5.
Chem Sci ; 13(21): 6233-6243, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35733906

ABSTRACT

Modulation of N-glycosylation using human Golgi α-mannosidase II (α-hGMII) inhibitors is a potential anticancer approach, but the clinical utility of current α-hGMII inhibitors is limited by their co-inhibition of human lysosomal α-mannosidase (α-hLM), resulting in abnormal storage of oligomannoses. We describe the synthesis and screening of a small library of novel bicyclic iminosugar-based scaffolds, prepared via natural product-inspired combinatorial chemistry (NPICC), which resulted in the identification of a primary α-hGMII inhibitor with 13.5-fold selectivity over α-hLM. Derivatization of this primary inhibitor using computation-guided synthesis (CGS) yielded an advanced α-hGMII inhibitor with nanomolar potency and 106-fold selectivity over α-hLM. In vitro studies demonstrated its N-glycan modulation and inhibitory effect on hepatocellular carcinoma (HCC) cells. In vivo studies confirmed its encouraging anti-HCC activity, without evidence of oligomannose accumulation.

6.
Bioorg Med Chem ; 67: 116819, 2022 08 01.
Article in English | MEDLINE | ID: mdl-35635930

ABSTRACT

A series of salicylanilide compounds was previously identified as antibacterial agents that inhibit the peptidoglycan formation. To find the exact binding mode, we synthesized a benzophenone-containing salicylanilide compound (1) and used it as a photoaffinity probe to label Acinetobacter baumannii penicillin-binding protein (PBP1b). After incubation and photo-irradiation, the labeled protein was subjected to trypsin digestion, dialysis enrichment, LC-ESI-MS/MS analysis, and Mascot search to reveal an octadecapeptide sequence 364RQLRTEYQESDLTNQGLR381 that was labeled at E372. Our molecular docking experiments suggest a hydrophobic pocket surrounded by R367 and E372 is the binding site of salicylanilide 1. The pocket lies in between the transglycosylase and transpeptidase domains, thus binding of salicylanilide 1 can block the propagation pathway to disrupt the growth of peptidoglycan chain.


Subject(s)
Peptidoglycan Glycosyltransferase , Benzophenones/pharmacology , Escherichia coli/metabolism , Molecular Docking Simulation , Peptidoglycan , Peptidoglycan Glycosyltransferase/chemistry , Peptidoglycan Glycosyltransferase/metabolism , Photoaffinity Labels , Salicylanilides , Tandem Mass Spectrometry
7.
Sci Transl Med ; 14(639): eabm0899, 2022 04 06.
Article in English | MEDLINE | ID: mdl-35230146

ABSTRACT

A major challenge to end the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is to develop a broadly protective vaccine that elicits long-term immunity. As the key immunogen, the viral surface spike (S) protein is frequently mutated, and conserved epitopes are shielded by glycans. Here, we revealed that S protein glycosylation has site-differential effects on viral infectivity. We found that S protein generated by lung epithelial cells has glycoforms associated with increased infectivity. Compared to the fully glycosylated S protein, immunization of S protein with N-glycans trimmed to the mono-GlcNAc-decorated state (SMG) elicited stronger immune responses and better protection for human angiotensin-converting enzyme 2 (hACE2) transgenic mice against variants of concern (VOCs). In addition, a broadly neutralizing monoclonal antibody was identified from SMG-immunized mice that could neutralize wild-type SARS-CoV-2 and VOCs with subpicomolar potency. Together, these results demonstrate that removal of glycan shields to better expose the conserved sequences has the potential to be an effective and simple approach for developing a broadly protective SARS-CoV-2 vaccine.


Subject(s)
COVID-19 Vaccines , Polysaccharides , Spike Glycoprotein, Coronavirus , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines/immunology , COVID-19 Vaccines/metabolism , Humans , Mice , Models, Animal , SARS-CoV-2 , Vaccination
8.
ACS Chem Biol ; 16(10): 2016-2025, 2021 10 15.
Article in English | MEDLINE | ID: mdl-34649433

ABSTRACT

While the improved treatment of human immunodeficiency virus type 1 (HIV-1) infection is available, the development of an effective and safe prophylactic vaccine against HIV-1 is still an unrealized goal. Encouragingly, the discovery of broadly neutralizing antibodies (bNAbs) from HIV-1 positive patients that are capable of neutralizing a broad spectrum of HIV-1 isolates of various clades has accelerated the progress of vaccine development in the past few years. Some of these bNAbs recognize the N-glycans on the viral surface gp120 glycoprotein. We have been interested in using the glycan epitopes recognized by bNAbs for the development of vaccines to elicit bNAb-like antibodies with broadly neutralizing activities. Toward this goal, we have identified novel hybrid-type structures with subnanomolar avidity toward several bNAbs including PG16, PGT121, PGT128-3C, 2G12, VRC13, VRC-PG05, VRC26.25, VRC26.09, PGDM1400, 35O22, and 10-1074. Here, we report the immunogenicity evaluation of a novel hybrid glycan conjugated to carrier DTCRM197, a nontoxic mutant of the diphtheria toxin, for immunization in mice. Our results indicated that the IgG response was mainly against the chitobiose motif with nonspecific binding to a panel of N-glycans with reducing end GlcNAc-GlcNAc (chitobiose) printed on the glass slides. However, the IgM response was mainly toward the reducing end GlcNAc moiety. We further used the glycoconjugates of Man3GlcNAc2, Man5GlcNAc2, and Man9GlcNAc2 glycans for immunization, and a similar specificity pattern was observed. These findings suggest that the immunogenicity of chitobiose may interfere with the outcome of N-glycan-based vaccines, and modification may be necessary to increase the immunogenicity of the entire N-glycan epitope.


Subject(s)
AIDS Vaccines/immunology , Broadly Neutralizing Antibodies/immunology , Glycoconjugates/immunology , HIV Antibodies/immunology , Polysaccharides/immunology , Acetylglucosamine/immunology , Animals , Bacterial Proteins/chemistry , Carbohydrate Sequence , Disaccharides/immunology , Epitopes , Female , Glycoconjugates/chemical synthesis , HIV-1/immunology , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Mice, Inbred C57BL , Polysaccharides/chemical synthesis , Vaccine Development
9.
PLoS Pathog ; 17(8): e1009724, 2021 08.
Article in English | MEDLINE | ID: mdl-34352041

ABSTRACT

Hemagglutinin (HA) is the immunodominant protein of the influenza virus. We previously showed that mice injected with a monoglycosylated influenza A HA (HAmg) produced cross-strain-reactive antibodies and were better protected than mice injected with a fully glycosylated HA (HAfg) during lethal dose challenge. We employed a single B-cell screening platform to isolate the cross-protective monoclonal antibody (mAb) 651 from mice immunized with the HAmg of A/Brisbane/59/2007 (H1N1) influenza virus (Bris/07). The mAb 651 recognized the head domain of a broad spectrum of HAs from groups 1 and 2 influenza A viruses and offered prophylactic and therapeutic efficacy against A/California/07/2009 (H1N1) (Cal/09) and Bris/07 infections in mice. The antibody did not possess neutralizing activity; however, antibody-dependent cellular cytotoxicity and antibody-dependent cellular phagocytosis mediated by natural killer cells and alveolar macrophages were important in the protective efficacy of mAb 651. Together, this study highlighted the significance of effector functions for non-neutralizing antibodies to exhibit protection against influenza virus infection.


Subject(s)
Antibodies, Monoclonal/pharmacology , Antibodies, Neutralizing/pharmacology , Antibody-Dependent Cell Cytotoxicity , Influenza A virus/immunology , Killer Cells, Natural/immunology , Macrophages, Alveolar/immunology , Orthomyxoviridae Infections/prevention & control , Animals , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Antibodies, Viral/pharmacology , Female , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Killer Cells, Natural/drug effects , Killer Cells, Natural/virology , Macrophages, Alveolar/drug effects , Macrophages, Alveolar/virology , Mice , Mice, Inbred BALB C , Orthomyxoviridae Infections/immunology , Orthomyxoviridae Infections/virology
10.
Sci Rep ; 11(1): 8692, 2021 04 22.
Article in English | MEDLINE | ID: mdl-33888738

ABSTRACT

A metal nanoparticle composite, namely TPNT1, which contains Au-NP (1 ppm), Ag-NP (5 ppm), ZnO-NP (60 ppm) and ClO2 (42.5 ppm) in aqueous solution was prepared and characterized by spectroscopy, transmission electron microscopy, dynamic light scattering analysis and potentiometric titration. Based on the in vitro cell-based assay, TPNT1 inhibited six major clades of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with effective concentration within the range to be used as food additives. TPNT1 was shown to block viral entry by inhibiting the binding of SARS-CoV-2 spike proteins to the angiotensin-converting enzyme 2 (ACE2) receptor and to interfere with the syncytium formation. In addition, TPNT1 also effectively reduced the cytopathic effects induced by human (H1N1) and avian (H5N1) influenza viruses, including the wild-type and oseltamivir-resistant virus isolates. Together with previously demonstrated efficacy as antimicrobials, TPNT1 can block viral entry and inhibit or prevent viral infection to provide prophylactic effects against both SARS-CoV-2 and opportunistic infections.


Subject(s)
Gold/pharmacology , Influenza A Virus, H1N1 Subtype/physiology , Influenza A Virus, H5N1 Subtype/physiology , SARS-CoV-2/physiology , Silver/pharmacology , Zinc Oxide/pharmacology , Angiotensin-Converting Enzyme 2/metabolism , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Drug Resistance, Viral/drug effects , Food Additives/pharmacology , Gold/chemistry , HEK293 Cells , Humans , Influenza A Virus, H1N1 Subtype/drug effects , Influenza A Virus, H5N1 Subtype/drug effects , Metal Nanoparticles/chemistry , Nanocomposites/chemistry , Oseltamivir/pharmacology , Particle Size , Protein Binding/drug effects , SARS-CoV-2/drug effects , Silver/chemistry , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization/drug effects , Zinc Oxide/chemistry
11.
Proc Natl Acad Sci U S A ; 118(5)2021 02 02.
Article in English | MEDLINE | ID: mdl-33452205

ABSTRACT

The outbreak of COVID-19 caused by SARS-CoV-2 has resulted in more than 50 million confirmed cases and over 1 million deaths worldwide as of November 2020. Currently, there are no effective antivirals approved by the Food and Drug Administration to contain this pandemic except the antiviral agent remdesivir. In addition, the trimeric spike protein on the viral surface is highly glycosylated and almost 200,000 variants with mutations at more than 1,000 positions in its 1,273 amino acid sequence were reported, posing a major challenge in the development of antibodies and vaccines. It is therefore urgently needed to have alternative and timely treatments for the disease. In this study, we used a cell-based infection assay to screen more than 3,000 agents used in humans and animals, including 2,855 small molecules and 190 traditional herbal medicines, and identified 15 active small molecules in concentrations ranging from 0.1 nM to 50 µM. Two enzymatic assays, along with molecular modeling, were then developed to confirm those targeting the virus 3CL protease and the RNA-dependent RNA polymerase. Several water extracts of herbal medicines were active in the cell-based assay and could be further developed as plant-derived anti-SARS-CoV-2 agents. Some of the active compounds identified in the screen were further tested in vivo, and it was found that mefloquine, nelfinavir, and extracts of Ganoderma lucidum (RF3), Perilla frutescens, and Mentha haplocalyx were effective in a challenge study using hamsters as disease model.


Subject(s)
Antiviral Agents/pharmacology , COVID-19 Drug Treatment , SARS-CoV-2/drug effects , Adult , Animals , Antiviral Agents/chemistry , Antiviral Agents/therapeutic use , COVID-19/epidemiology , COVID-19/virology , Chlorocebus aethiops , Cricetinae , Disease Models, Animal , Drug Repositioning/methods , Female , Humans , Male , Pandemics , Plant Extracts/pharmacology , SARS-CoV-2/genetics , Vero Cells
12.
Proc Natl Acad Sci U S A ; 117(30): 17757-17763, 2020 07 28.
Article in English | MEDLINE | ID: mdl-32669430

ABSTRACT

Vaccination has been used to control the spread of seasonal flu; however, the virus continues to evolve and escape from host immune response through mutation and increasing glycosylation. Efforts have been directed toward development of a universal vaccine with broadly protective activity against multiple influenza strains and subtypes. Here we report the design and evaluation of various chimeric vaccines based on the most common avian influenza H5 and human influenza H1 sequences. Of these constructs, the chimeric HA (cHA) vaccine with consensus H5 as globular head and consensus H1 as stem was shown to elicit broadly protective CD4+ and CD8+ T cell responses. Interestingly, the monoglycosylated cHA (cHAmg) vaccine with GlcNAc on each glycosite induced more stem-specific antibodies, with higher antibody-dependent cellular cytotoxicity (ADCC), and better neutralizing and stronger cross-protection activities against H1, H3, H5, and H7 strains and subtypes. Moreover, the cHAmg vaccine combined with a glycolipid adjuvant designed for class switch further enhanced the vaccine efficacy with more IFN-γ, IL-4, and CD8+ memory T cells produced.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Cross Protection/immunology , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Influenza Vaccines/immunology , Influenza, Human/prevention & control , Orthomyxoviridae/immunology , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Antibody-Dependent Cell Cytotoxicity , CD4-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/metabolism , Disease Models, Animal , Hemagglutinin Glycoproteins, Influenza Virus/chemistry , Humans , Influenza, Human/virology , Mice , Models, Molecular , Neutralization Tests , Orthomyxoviridae/classification , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/immunology , Structure-Activity Relationship , Vaccination
13.
J Med Chem ; 63(6): 3172-3187, 2020 03 26.
Article in English | MEDLINE | ID: mdl-32125853

ABSTRACT

Drug resistance has been a major threat in cancer therapies that necessitates the development of new strategies to overcome this problem. We report here a cell-based high-throughput screen of a library containing two-million molecules for the compounds that inhibit the proliferation of non-small-cell lung cancer (NSCLC). Through the process of phenotypic screening, target deconvolution, and structure-activity relationship (SAR) analysis, a compound of furanonaphthoquinone-based small molecule, AS4583, was identified that exhibited potent activity in tyrosine kinase inhibitor (TKI)-sensitive and TKI-resistant NSCLC cells (IC50 = 77 nM) and in xenograft mice. The mechanistic studies revealed that AS4583 inhibited cell-cycle progression and reduced DNA replication by disrupting the formation of the minichromosomal maintenance protein (MCM) complex. Subsequent SAR study of AS4583 gave compound RJ-LC-07-48 which exhibited greater potency in drug-resistant NSCLC cells (IC50 = 17 nM) and in mice with H1975 xenograft tumor.


Subject(s)
Antineoplastic Agents/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Furans/therapeutic use , Lung Neoplasms/drug therapy , Minichromosome Maintenance Proteins/metabolism , Naphthoquinones/therapeutic use , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/metabolism , Binding Sites , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Resistance, Neoplasm/drug effects , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/metabolism , Enzyme Inhibitors/therapeutic use , Furans/chemical synthesis , Furans/metabolism , High-Throughput Screening Assays , Humans , Mice, Nude , Molecular Docking Simulation , Molecular Structure , Naphthoquinones/chemical synthesis , Naphthoquinones/metabolism , Protein Binding , Small Molecule Libraries/pharmacology , Structure-Activity Relationship , Ubiquitination/drug effects , Xenograft Model Antitumor Assays
14.
J Am Chem Soc ; 142(11): 5282-5292, 2020 03 18.
Article in English | MEDLINE | ID: mdl-32083852

ABSTRACT

Human endo-O-sulfatases (Sulf-1 and Sulf-2) are extracellular heparan sulfate proteoglycan (HSPG)-specific 6-O-endosulfatases, which regulate a multitude of cell-signaling events through heparan sulfate (HS)-protein interactions and are associated with the onset of osteoarthritis. These endo-O-sulfatases are transported onto the cell surface to liberate the 6-sulfate groups from the internal d-glucosamine residues in the highly sulfated subdomains of HSPGs. In this study, a variety of HS oligosaccharides with different chain lengths and N- and O-sulfation patterns via chemical synthesis were systematically studied about the substrate specificity of human Sulf-1 employing the fluorogenic substrate 4-methylumbelliferyl sulfate (4-MUS) in a competition assay. The trisaccharide sulfate IdoA2S-GlcNS6S-IdoA2S was found to be the minimal-size substrate for Sulf-1, and substitution of the sulfate group at the 6-O position of the d-glucosamine unit with the sulfonamide motif effectively inhibited the Sulf-1 activity with IC50 = 0.53 µM, Ki = 0.36 µM, and KD = 12 nM.


Subject(s)
Enzyme Inhibitors/chemistry , Sulfatases/antagonists & inhibitors , Sulfonamides/chemistry , Sulfotransferases/antagonists & inhibitors , Trisaccharides/chemistry , Enzyme Assays , Enzyme Inhibitors/chemical synthesis , Heparitin Sulfate/chemistry , Humans , Kinetics , Substrate Specificity , Sulfatases/chemistry , Sulfonamides/chemical synthesis , Sulfotransferases/chemistry , Trisaccharides/chemical synthesis
15.
Genome Biol Evol ; 12(2): 3890-3905, 2020 02 01.
Article in English | MEDLINE | ID: mdl-31971587

ABSTRACT

Tuberculosis (TB), an infectious disease caused by Mycobacterium tuberculosis, kills over 1 million people worldwide annually. Development of drug resistance (DR) in the pathogen is a major challenge for TB control. We conducted whole-genome analysis of seven Taiwan M. tuberculosis isolates: One drug susceptible (DS) and five DR Beijing lineage isolates and one DR Euro-American lineage isolate. Developing a new method for DR mutation identification and applying it to the next-generation sequencing (NGS) data from the 6 Beijing lineage isolates, we identified 13 known and 6 candidate DR mutations and provided experimental support for 4 of them. We assembled the genomes of one DS and two DR Beijing lineage isolates and the Euro-American lineage isolate using NGS data. Moreover, using both PacBio and NGS sequencing data, we obtained a high-quality assembly of an extensive DR Beijing lineage isolate. Comparative analysis of these five newly assembled genomes and two published complete genomes revealed a large number of genetic changes, including gene gains and losses, indels and translocations, suggesting rapid evolution of M. tuberculosis. We found the MazEF toxin-antitoxin system in all the seven isolates studied and several interesting mutations in MazEF proteins. Finally, we used the four assembled Beijing lineage genomes to construct a high-quality Beijing lineage reference genome that is DS and contains all the genes in the four genomes. It contains 212 genes not found in the standard reference H37Rv, which is Euro-American. It is therefore a better reference than H37Rv for the Beijing lineage, the predominant lineage in Asia.


Subject(s)
Genome, Bacterial/genetics , Mycobacterium tuberculosis/genetics , Bacterial Proteins/genetics , Beijing , Drug Resistance, Multiple, Bacterial/genetics , INDEL Mutation/genetics , Mutation/genetics , Mycobacterium tuberculosis/classification , Phylogeny
16.
J Med Chem ; 63(1): 205-215, 2020 01 09.
Article in English | MEDLINE | ID: mdl-31769665

ABSTRACT

Antiviral drug resistance in influenza infections has been a major threat to public health. To develop a broad-spectrum inhibitor of influenza to combat the problem of drug resistance, we previously identified the highly conserved E339...R416 salt bridge of the nucleoprotein trimer as a target and compound 1 as an inhibitor disrupting the salt bridge with an EC50 = 2.7 µM against influenza A (A/WSN/1933). We have further modified this compound via a structure-based approach and performed antiviral activity screening to identify compounds 29 and 30 with EC50 values of 110 and 120 nM, respectively, and without measurable host cell cytotoxicity. Compared to the clinically used neuraminidase inhibitors, these two compounds showed better activity profiles against drug-resistant influenza A strains, as well as influenza B, and improved survival of influenza-infected mice.


Subject(s)
Aniline Compounds/pharmacology , Antiviral Agents/pharmacology , Influenza A virus/chemistry , Protein Multimerization/drug effects , RNA-Binding Proteins/metabolism , Thiazoles/pharmacology , Viral Core Proteins/metabolism , Aniline Compounds/chemical synthesis , Aniline Compounds/metabolism , Animals , Antiviral Agents/chemical synthesis , Antiviral Agents/metabolism , Binding Sites/drug effects , Female , Mice, Inbred BALB C , Molecular Docking Simulation , Molecular Structure , Nucleocapsid Proteins , Protein Binding , Static Electricity , Structure-Activity Relationship , Thiazoles/chemical synthesis , Thiazoles/metabolism
17.
J Biomed Sci ; 26(1): 97, 2019 Dec 20.
Article in English | MEDLINE | ID: mdl-31861989

ABSTRACT

BACKGROUND: Dectin-2, which is a C-type lectin, interacts with the house dust mite (HDM) Dermatophagoides pteronyssinus allergen. This study aimed to investigate whether Dectin-2 blockade by antagonistic monoclonal antibodies (MoAbs) attenuates HDM-induced allergic responses. METHODS: Two anti-Dectin-2 MoAbs were generated and validated for specific binding to Dectin-2 Fc fusion protein (Dectin-2.Fc) and inhibition of Dectin-2.Fc/HDM interaction. Patients with asthma exhibiting high titers of anti-D. pteronyssinus IgE were enrolled. Peripheral blood mononuclear cells with depleted CD14+ monocytes were obtained from these patients and co-cultured with autologous monocyte-derived conventional dendritic cells in the presence of D. pteronyssinus or its group 2 allergens (Der p 2). Interleukin (IL)-5 and IL-13 levels in the culture supernatants were determined using ELISA in the presence or absence of anti-Dectin-2 MoAbs. RESULTS: Two MoAbs, 6A4G7 and 17A1D10, showed specific binding to recombinant Dectin-2.Fc and inhibited HDM binding to Dectin-2.Fc. Both anti-Dectin-2 MoAbs inhibited IL-5 and IL-13 production in co-cultures with Der p 2 stimulation in a dose-dependent manner. 6A4G7 and 17A1D10 (3 µg/mL) significantly inhibited Der p 2-induced (3 µg/mL) IL-5 production by 69.7 and 86.4% and IL-13 production by 84.0 and 81.4%, respectively. Moreover, this inhibitory effect of the two MoAbs remained significant in the presence of D. pteronyssinus. CONCLUSIONS: Anti-Dectin-2 MoAbs significantly inhibited HDM-induced allergic responses in vitro and therefore have the potential to become therapeutic agents in mite-induced allergic diseases.


Subject(s)
Antibodies, Blocking/immunology , Asthma/immunology , Cytokines/immunology , Dendritic Cells/immunology , Lectins, C-Type/immunology , Leukocytes, Mononuclear/immunology , Pyroglyphidae/immunology , Adult , Animals , Cells, Cultured , Female , Humans , Male , Mice , Mice, Knockout , Middle Aged , Th2 Cells
18.
Eur J Med Chem ; 181: 111551, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31376567

ABSTRACT

An 8-oxopurine-6-carboxamide compound (1a) was previously identified as an inhibitor of non-small cell lung cancer (NSCLC). In this study, more than 30 purine-6-carboxamide derivatives with variations at the C2, N7, C8, and N9 positions were synthesized to investigate the structure-activity relationship as a basis for the construction of an advanced pharmacophore model. This model suggests that purine-6-hydroxamate and purine-6-amidoxime analogs could form more hydrogen bonds with a target protein to enhance the inhibitory activities against H1975 cells. Among the series of analogs, hydroxamate 17 and amidoxime 19a exhibited excellent potency against H1975 cells (IC50 < 1.5 µM) and other lung cancer cells with either wild-type or mutated epidermal growth factor receptor (EGFR). Mouse experiments indicated that compounds 17 and 19a were efficient anticancer agents with no appreciable toxicity. The mechanisms of action for the induction of cell apoptosis were determined to involve microtubule fragmentation and p53-mediated signaling pathways.


Subject(s)
Amides/pharmacology , Antineoplastic Agents/pharmacology , Carcinoma, Non-Small-Cell Lung/drug therapy , Hydroxamic Acids/pharmacology , Lung Neoplasms/drug therapy , Oximes/pharmacology , Purines/pharmacology , Amides/chemistry , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Hydroxamic Acids/chemistry , Lung Neoplasms/pathology , Mice , Mice, Nude , Molecular Structure , Neoplasms, Experimental/drug therapy , Neoplasms, Experimental/pathology , Oximes/chemistry , Purines/chemistry , Structure-Activity Relationship
19.
Eur J Med Chem ; 181: 111584, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31419740

ABSTRACT

Developing new therapeutic strategies to overcome drug resistance of cancer cells is an ongoing endeavor. From among 2 million chemicals, we identified ethyl 4-oxo-2-phenyl-1,4-dihydroquinoline-6-carboxylate (AS1712) as a low-toxicity inhibitor of lung cancer cell proliferation and xenograft tumor growth. We show that AS1712 is active against broad cancer cell lines and is able to bind in the colchicine-binding pocket of ß-tubulin, thereby inhibiting microtubule assembly and, consequently, inducing mitotic arrest and apoptosis. Our cell-based structure-activity relationship study identified a new lead compound, RJ-LC-15-8, which had a greater anti-proliferative potency for H1975 cells than did AS1712, while maintaining a similar mechanism of action. Notably, AS1712 and RJ-LC-15-8 overcame P-glycoprotein efflux pump and ß-tubulin alterations that lead to acquired resistance against microtubule-targeting drugs of cancer cells. AS1712 and RJ-LC-15-8 may be lead compounds that overcome acquired resistance to microtubule-targeting agents of cancer cells.


Subject(s)
Quinolones/chemistry , Quinolones/pharmacology , Tubulin Modulators/chemistry , Tubulin Modulators/pharmacology , Tubulin/metabolism , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Binding Sites/drug effects , Cell Proliferation/drug effects , Colchicine/metabolism , Drug Resistance, Neoplasm , Humans , Molecular Docking Simulation , Neoplasms/drug therapy , Neoplasms/metabolism , Tubulin/chemistry
20.
Int J Biol Macromol ; 135: 29-37, 2019 Aug 15.
Article in English | MEDLINE | ID: mdl-31121231

ABSTRACT

Ginseng marc is a major by-product of the ginseng industry currently used as animal feed or fertilizer. This fibrous, insoluble waste stream is rich in cell wall polysaccharides and therefore a potential source of ingredients for functional food with health-promoting properties. However, the extraction of these polysaccharides has proved problematic and their exact composition remains unknown. Here we have analysed the composition, structure and biological activity of polysaccharides from ginseng root, stem and leaf marc fractionated using a chelator and alkali solutions. The pectic fraction has been extracted from root marc in high abundance and can activate the production of interleukine-1α and the hematopoietic growth factor by RAW 264.7 murine macrophage cells, which are important immune regulators of T-cells during inflammatory responses and infection processes. Our study reveals the potential to increase the value of ginseng marc by generating carbohydrate-based products with a higher value than animal feed.


Subject(s)
Cell Wall/chemistry , Panax/chemistry , Polysaccharides/chemistry , Polysaccharides/pharmacology , Animals , Hydrolysis , Immunologic Factors/chemistry , Immunologic Factors/isolation & purification , Immunologic Factors/pharmacology , Liquid-Liquid Extraction , Mice , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Polysaccharides/isolation & purification , RAW 264.7 Cells , Spectrum Analysis , Structure-Activity Relationship
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