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1.
Curr Protoc ; 1(11): e305, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34826352

RESUMO

All eukaryotic cells are covered with a dense layer of glycoconjugates, and the cell walls of bacteria are made of various polysaccharides, putting glycans in key locations for mediating protein-protein interactions at cell interfaces. Glycan function is therefore mainly defined as binding to other molecules, and lectins are proteins that specifically recognize and interact non-covalently with glycans. UniLectin was designed based on insight into the knowledge of lectins, their classification, and their biological role. This modular platform provides a curated and periodically updated classification of lectins along with a set of comparative and visualization tools, as well as structured results of screening comprehensive sequence datasets. UniLectin can be used to explore lectins, find precise information on glycan-protein interactions, and mine the results of predictive tools based on HMM profiles. This usage is illustrated here with two protocols. The first one highlights the fine-tuned role of the O blood group antigen in distinctive pathogen recognition, while the second compares the various bacterial lectin arsenals that clearly depend on living conditions of species even in the same genus. © 2021 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Searching for the structural details of lectins binding the O blood group antigen Basic Protocol 2: Comparing the lectomes of related organisms in different environments.


Assuntos
Glicoconjugados , Lectinas , Proteínas de Transporte , Lectinas/metabolismo , Polissacarídeos
2.
Colloids Surf B Biointerfaces ; 208: 112148, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34624598

RESUMO

Carbohydrates and glycoconjugates are involved in numerous natural and pathological metabolic processes, and the precise elucidation of their biochemical functions has been supported by smart technologies assembled with lectins, i.e., ubiquitous proteins of nonimmune origin with carbohydrate-specific domains. When lectins are anchored on suitable electrochemical transducers, sensitive and innovative bioanalytical tools (lectin-based biosensors) are produced, with the ability to screen target sugars at molecular levels. In addition to the remarkable electroanalytical sensitivity, these devices associate specificity, precision, stability, besides the possibility of miniaturization and portability, which are special features required for real-time and point-of-care measurements. The mentioned attributes can be improved by combining lectins with biocompatible 0-3D semiconductors derived from carbon, metal nanoparticles, polymers and their nanocomposites, or employing labeled biomolecules. This systematic review aims to substantiate and update information on the progress made with lectin-based biosensors designed for electroanalysis of clinically relevant carbohydrates and glycoconjugates (glycoproteins, pathogens and cancer biomarkers), highlighting their main detection principles and performance in highly complex biological milieus. Moreover, particular emphasis is given to the main advantages and limitations of the reported devices, as well as the new trends for the current demands. We believe that this review will support and encourage more cutting-edge research involving lectin-based electrochemical biosensors.


Assuntos
Técnicas Biossensoriais , Lectinas , Carboidratos , Glicoconjugados , Glicoproteínas
3.
Int J Mol Sci ; 22(19)2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34638669

RESUMO

Extracellular vesicles (EVs) are found in all biological fluids, providing potential for the identification of disease biomarkers such as colorectal cancer (CRC). EVs are heavily glycosylated with specific glycoconjugates such as tetraspanins, integrins, and mucins, reflecting the characteristics of the original cell offering valuable targets for detection of CRC. We report here on europium-nanoparticle (EuNP)-based assay to detect and characterize different surface glycoconjugates of EVs without extensive purification steps from five different CRC and the HEK 293 cell lines. The promising EVs candidates from cell culture were clinically evaluated on small panel of serum samples including early-stage (n = 11) and late-stage (n = 11) CRC patients, benign condition (n = 11), and healthy control (n = 10). The majority of CRC cell lines expressed tetraspanin sub-population and glycovariants of integrins and conventional tumor markers. The subpopulation of CD151 having CD63 expression (CD151CD63) was significantly (p = 0.001) elevated in early-stage CRC (8 out of 11) without detecting any benign and late-stage samples, while conventional CEA detected mostly late-stage CRC (p = 0.045) and with only four early-stage cases. The other glycovariant assays such as CEACon-A, CA125WGA, CA 19.9Ma696, and CA 19.9Con-A further provided some complementation to the CD151CD63 assay. These results indicate the potential application of CD151CD63 assay for early detection of CRC patients in human serum.


Assuntos
Neoplasias Colorretais/sangue , Neoplasias Colorretais/metabolismo , Vesículas Extracelulares/metabolismo , Glicoconjugados/sangue , Glicoconjugados/metabolismo , Nanopartículas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/metabolismo , Antígeno Ca-125/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Células HEK293 , Humanos , Masculino , Pessoa de Meia-Idade , Tetraspanina 30/metabolismo , Tetraspaninas/metabolismo , Adulto Jovem
4.
ACS Chem Biol ; 16(9): 1671-1679, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34469105

RESUMO

Vaccination represents the most effective way to prevent invasive pneumococcal diseases. The glycoconjugate vaccines licensed so far are obtained from capsular polysaccharides (CPSs) of the most virulent serotypes. Protection is largely limited to the specific vaccine serotypes, and the continuous need for broader coverage to control the outbreak of emerging serotypes is pushing the development of new vaccine candidates. Indeed, the development of efficacious vaccine formulation is complicated by the high number of bacterial serotypes with different CPSs. In this context, to simplify vaccine composition, we propose the design of new saccharide fragments containing chemical structures shared by different serotypes as cross-reactive and potentially cross-protective common antigens. In particular, we focused on Streptococcus pneumoniae (Sp) 19A and 19F. The CPS repeating units of Sp 19F and 19A are very similar and share a common structure, the disaccharide ManNAc-ß-(1→4)-Glc (A-B). Herein, we describe the synthesis of a small library of compounds containing different combinations of the common 19F/19A disaccharide. The six new compounds were tested with a glycan array to evaluate their recognition by antibodies in reference group 19 antisera and factor reference antisera (reacting against 19F or 19A). The disaccharide A-B, phosphorylated at the upstream end, emerged as a hit from the glycan array screening because it is strongly recognized by the group 19 antisera and by the 19F and 19A factor antisera, with similar intensity compared with the CPSs used as controls. Our data give a strong indication that the phosphorylated disaccharide A-B can be considered a common epitope among different Sp 19 serotypes.


Assuntos
Epitopos/química , Glicoconjugados/análise , Proteínas Imobilizadas/química , Polissacarídeos Bacterianos/análise , Anticorpos/química , Técnicas Biossensoriais , Reações Cruzadas , Glicoconjugados/metabolismo , Hexosaminas/química , Polissacarídeos Bacterianos/metabolismo , Sorogrupo , Soro/química , Espectrometria de Fluorescência , Streptococcus pneumoniae/metabolismo , Propriedades de Superfície
5.
Biochem Soc Trans ; 49(5): 2411-2429, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34495299

RESUMO

The importance of vaccine-induced protection was repeatedly demonstrated over the last three decades and emphasized during the recent COVID-19 pandemic as the safest and most effective way of preventing infectious diseases. Vaccines have controlled, and in some cases, eradicated global viral and bacterial infections with high efficiency and at a relatively low cost. Carbohydrates form the capsular sugar coat that surrounds the outer surface of human pathogenic bacteria. Specific surface-exposed bacterial carbohydrates serve as potent vaccine targets that broadened our toolbox against bacterial infections. Since first approved for commercial use, antibacterial carbohydrate-based vaccines mostly rely on inherently complex and heterogenous naturally derived polysaccharides, challenging to obtain in a pure, safe, and cost-effective manner. The introduction of synthetic fragments identical with bacterial capsular polysaccharides provided well-defined and homogenous structures that resolved many challenges of purified polysaccharides. The success of semisynthetic glycoconjugate vaccines against bacterial infections, now in different phases of clinical trials, opened up new possibilities and encouraged further development towards fully synthetic antibacterial vaccine solutions. In this mini-review, we describe the recent achievements in semi- and fully synthetic carbohydrate vaccines against a range of human pathogenic bacteria, focusing on preclinical and clinical studies.


Assuntos
Antibacterianos/imunologia , Bactérias/imunologia , Infecções Bacterianas/imunologia , Carboidratos/imunologia , Glicoconjugados/imunologia , Vacinas Sintéticas/imunologia , Antibacterianos/química , Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Infecções Bacterianas/microbiologia , Infecções Bacterianas/prevenção & controle , COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/uso terapêutico , Sequência de Carboidratos , Carboidratos/química , Glicoconjugados/química , Glicoconjugados/uso terapêutico , Humanos , Vacinas Sintéticas/química , Vacinas Sintéticas/uso terapêutico
6.
J Med Chem ; 64(19): 14332-14343, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34524803

RESUMO

In addition to a variety of viral-glycoprotein receptors (e.g., heparan sulfate, Niemann-Pick C1, etc.), dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN), from the C-type lectin receptor family, plays one of the most important pathogenic functions for a wide range of viruses (e.g., Ebola, human cytomegalovirus (HCMV), HIV-1, severe acute respiratory syndrome coronavirus 2, etc.) that invade host cells before replication; thus, its inhibition represents a relevant extracellular antiviral therapy. We report two novel p-tBu-calixarene glycoclusters 1 and 2, bearing tetrahydroxamic acid groups, which exhibit micromolar inhibition of soluble DC-SIGN binding and provide nanomolar IC50 inhibition of both DC-SIGN-dependent Jurkat cis-cell infection by viral particle pseudotyped with Ebola virus glycoprotein and the HCMV-gB-recombinant glycoprotein interaction with monocyte-derived dendritic cells expressing DC-SIGN. A unique cooperative involvement of sugar, linker, and calixarene core is likely behind the strong avidity of DC-SIGN for these low-valent systems. We claim herein new promising candidates for the rational development of a large spectrum of antiviral therapeutics.


Assuntos
Calixarenos/química , Moléculas de Adesão Celular/antagonistas & inibidores , Glicoconjugados/metabolismo , Glicoproteínas/antagonistas & inibidores , Ácidos Hidroxâmicos/química , Lectinas Tipo C/antagonistas & inibidores , Fenóis/química , Receptores de Superfície Celular/antagonistas & inibidores , Proteínas Virais/antagonistas & inibidores , Antivirais/química , Antivirais/metabolismo , Antivirais/farmacologia , Moléculas de Adesão Celular/metabolismo , Linhagem Celular , Citomegalovirus/metabolismo , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Ebolavirus/fisiologia , Glicoconjugados/química , Glicoconjugados/farmacologia , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Células Jurkat , Lectinas Tipo C/metabolismo , Modelos Biológicos , Ligação Proteica , Receptores de Superfície Celular/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Virais/genética , Proteínas Virais/metabolismo
7.
Sci Rep ; 11(1): 16109, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34373510

RESUMO

Scedosporium apiospermum is an emerging opportunistic fungal pathogen responsible for life-threatening infections in humans. Host-pathogen interactions often implicate lectins that have become therapeutic targets for the development of carbohydrate mimics for antiadhesive therapy. Here, we present the first report on the identification and characterization of a lectin from S. apiospermum named SapL1. SapL1 was found using bioinformatics as a homolog to the conidial surface lectin FleA from Aspergillus fumigatus known to play a role in the adhesion to host glycoconjugates present in human lung epithelium. In our strategy to obtain recombinant SapL1, we discovered the importance of osmolytes to achieve its expression in soluble form in bacteria. Analysis of glycan arrays indicates specificity for fucosylated oligosaccharides as expected. Submicromolar affinity was measured for fucose using isothermal titration calorimetry. We solved SapL1 crystal structure in complex with α-methyl-L-fucoside and analyzed its structural basis for fucose binding. We finally demonstrated that SapL1 binds to bronchial epithelial cells in a fucose-dependent manner. The information gathered here will contribute to the design and development of glycodrugs targeting SapL1.


Assuntos
Proteínas Fúngicas/metabolismo , Lectinas/metabolismo , Scedosporium/metabolismo , Sequência de Aminoácidos , Aspergillus fumigatus/metabolismo , Sítios de Ligação/fisiologia , Células Cultivadas , Células Epiteliais/metabolismo , Fucose/metabolismo , Glicoconjugados/metabolismo , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Oligossacarídeos/metabolismo , Polissacarídeos/metabolismo
8.
Sensors (Basel) ; 21(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34450954

RESUMO

I conducted this study to develop an improved method for glycome detection using fluorescent magnetic beads, whose surfaces were modified using lectins, for the highly sensitive detection of saccharides or glycoproteins via fluorescence quenching using a novel fluorescence emitter and quencher pair. The emitter (Cy3 fluorophore) was incorporated into magnetic beads, and a fluorescence quencher (cyanopyranyl group) was bound to glycomes via covalent bonding. The fluorescence intensities of fluorescent magnetic beads containing lectins decreased specifically in the presence of glycomes, which was a result of fluorescence quenching from Cy3 to cyanopyranyl groups due to the formation of a stable complex between lectins and glycome. Fluorescence intensities were plotted as a function of glycoprotein concentration, and good linear relationships were observed. This method enabled the fluorescent reading-out of a series of lectin-glycome interactions on the basis of recognition selectivity and affinity of immobilized lectins without tedious washing processes. Moreover, a simple profiling process was performed using this assay for diverse glycoconjugates, which not only included simple saccharides but also glycoproteins and glycome in cell lysates. These results clearly indicate that the combination of magnetic beads with the novel emitter-quencher pair enabled the highly sensitive detection of lectin-glycome interactions.


Assuntos
Glicoconjugados , Lectinas , Corantes Fluorescentes , Glicoproteínas , Magnetismo
9.
Biologicals ; 72: 1-9, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34247915

RESUMO

Shigellosis, a diarrheal disorder caused by an entero-invasive bacterium Shigella, is a major concern among children often leading to mortality. As most of these strains have developed universal antibiotic resistance, the development of a vaccine is crucial in combating the infection. The O-specific polysaccharide (O-PSs) from S. flexneri type 2a is considered to be the major disease-causing antigen in shigellosis. Therefore, the O-PSs conjugated with carrier proteins, can serve as a potential high molecular weight vaccine candidate. Accordingly, in the present study, O-PS extracted from S. flexneri 2a is conjugated with Cross-Reactive Material (CRM197), a non-toxic mutant of diphtheria toxin. We derivatized CRM197 and O-PS separately with adipic acid dihydrazide (ADH) and reacted with their counterparts to probe the conjugation efficacy. Among the two strategies, the CRM197-ADH treated with O-PS has yielded a stable glycoconjugate of 311 kDa. The conjugation efficiency has been probed by estimating the free protein, free O-PS and O-PS:CRM197 ratio using slot-blot, size exclusion and high-performance anion exchange chromatography techniques. The conjugate exhibited enhanced shelf-life of three months. The cytotoxicity studies with Vero/MRC-5 cells have confirmed the non-toxicity of the conjugate, which makes the glycoconjugate a potential vaccine candidate for shigellosis.


Assuntos
Disenteria Bacilar , Glicoconjugados , Antígenos O , Vacinas contra Shigella/imunologia , Shigella flexneri , Animais , Chlorocebus aethiops , Disenteria Bacilar/prevenção & controle , Vacinas Conjugadas , Células Vero
10.
Commun Biol ; 4(1): 828, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34211117

RESUMO

The heterotrimeric Sec61 complex is a major site for the biogenesis of transmembrane proteins (TMPs), accepting nascent TMP precursors that are targeted to the endoplasmic reticulum (ER) by the signal recognition particle (SRP). Unlike most single-spanning membrane proteins, the integration of type III TMPs is completely resistant to small molecule inhibitors of the Sec61 translocon. Using siRNA-mediated depletion of specific ER components, in combination with the potent Sec61 inhibitor ipomoeassin F (Ipom-F), we show that type III TMPs utilise a distinct pathway for membrane integration at the ER. Hence, following SRP-mediated delivery to the ER, type III TMPs can uniquely access the membrane insertase activity of the ER membrane complex (EMC) via a mechanism that is facilitated by the Sec61 translocon. This alternative EMC-mediated insertion pathway allows type III TMPs to bypass the Ipom-F-mediated blockade of membrane integration that is seen with obligate Sec61 clients.


Assuntos
Retículo Endoplasmático/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de Membrana/metabolismo , Biossíntese de Proteínas , Canais de Translocação SEC/metabolismo , Animais , Retículo Endoplasmático/efeitos dos fármacos , Glicoconjugados/farmacologia , Células HeLa , Humanos , Immunoblotting , Membranas Intracelulares/efeitos dos fármacos , Modelos Biológicos , Transporte Proteico/efeitos dos fármacos , Interferência de RNA , Canais de Translocação SEC/genética , Partícula de Reconhecimento de Sinal/metabolismo
11.
mBio ; 12(3): e0122721, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34182777

RESUMO

Burkholderia pseudomallei is the causative agent of melioidosis, a fatal disease with a high mortality rate. The intrinsic resistance to commonly used antibiotics combined with the complex bacterial life cycle has hampered the development of preventive and therapeutic interventions and vaccines. Furthermore, the need of humoral and cell-mediated immunity in protection against B. pseudomallei has complicated the development of effective vaccines. Antigen delivery vaccine platforms that promote humoral and cellular responses while maintaining a safe profile are a roadblock to developing subunit vaccines against intracellular pathogens. Gold nanoparticles (AuNPs) were used for the delivery of multicomponent antigens with the goal of inducing vaccine-mediated immunity, promoting protection against melioidosis disease. Different nanoglycoconjugates using predicted immunogenic protein candidates, Hcp1, FlgL, OpcP, OpcP1, OmpW, and hemagglutinin, were covalently coupled to AuNPs, together with the lipopolysaccharide (LPS) from Burkholderia thailandensis, which acted as an additional antigen. Animals immunized with individually coupled (AuNP-protein-LPS) formulations containing OpcP or OpcP1, together with CpG as an adjuvant, showed a significant increase in protection, whereas a nanovaccine combination (AuNP-Combo2-LPS) showed significant and complete protection against a lethal intranasal B. pseudomallei challenge. Animals immunized with AuNP-Combo2-LPS showed robust humoral antigen-specific (IgG and IgA) responses with higher IgG2c titer, indicating a TH1-skewed response and promotion of macrophage uptake. In addition, immunization with the nanovaccine combination resulted in a mixed antigen-specific TH1-TH17 cytokine profile after immunization. This study provides the basis for an elegant and refined multicomponent glycoconjugate vaccine formulation capable of eliciting both humoral and cell-mediated responses against lethal B. pseudomallei challenge. IMPORTANCE Melioidosis is a complex human disease associated with a wide range of complications caused by the Gram-negative bacillus Burkholderia pseudomallei. The global burden of melioidosis is estimated to have 165,000 cases per year and 89,000 fatal outcomes. The endemicity of B. pseudomallei includes a wide range of tropical regions in Asia, Africa, Latin America, and Australia. Therefore, a viable alternative to prevent human infections is the development of an effective vaccine; however, no approved vaccine for human use is available. This study provides a vaccine strategy against B. pseudomallei and an immune-stimulatory platform to induce strong humoral and T-cell-mediated immunity.


Assuntos
Vacinas Bacterianas/imunologia , Burkholderia pseudomallei/imunologia , Ouro , Imunidade Humoral , Melioidose/prevenção & controle , Células Th1/imunologia , Células Th17/imunologia , Adjuvantes Imunológicos , Animais , Anticorpos Antibacterianos/sangue , Vacinas Bacterianas/administração & dosagem , Burkholderia/imunologia , Feminino , Glicoconjugados/química , Imunidade Celular , Melioidose/imunologia , Nanopartículas Metálicas/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Vacinação
12.
ChemMedChem ; 16(15): 2345-2353, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34061468

RESUMO

The C-type lectin receptor DC-SIGN mediates interactions with envelope glycoproteins of many viruses such as SARS-CoV-2, ebola, and HIV and contributes to virus internalization and dissemination. In the context of the recent SARS-CoV-2 pandemic, involvement of DC-SIGN has been linked to severe cases of COVID-19. Inhibition of the interaction between DC-SIGN and viral glycoproteins has the potential to generate broad spectrum antiviral agents. Here, we demonstrate that mannose-functionalized poly-l-lysine glycoconjugates efficiently inhibit the attachment of viral glycoproteins to DC-SIGN-presenting cells with picomolar affinity. Treatment of these cells leads to prolonged receptor internalization and inhibition of virus binding for up to 6 h. Furthermore, the polymers are fully bio-compatible and readily cleared by target cells. The thermodynamic analysis of the multivalent interactions reveals enhanced enthalpy-driven affinities and promising perspectives for the future development of multivalent therapeutics.


Assuntos
Antivirais/farmacologia , Moléculas de Adesão Celular/antagonistas & inibidores , Glicoconjugados/farmacologia , Lectinas Tipo C/antagonistas & inibidores , Receptores de Superfície Celular/antagonistas & inibidores , Ligação Viral/efeitos dos fármacos , Antivirais/síntese química , Antivirais/metabolismo , Moléculas de Adesão Celular/metabolismo , Glicoconjugados/síntese química , Glicoconjugados/metabolismo , Humanos , Lectinas Tipo C/metabolismo , Manose/análogos & derivados , Manose/metabolismo , Manose/farmacologia , Testes de Sensibilidade Microbiana , Polilisina/análogos & derivados , Polilisina/metabolismo , Polilisina/farmacologia , Ligação Proteica/efeitos dos fármacos , Receptores de Superfície Celular/metabolismo , SARS-CoV-2/efeitos dos fármacos , Células THP-1 , Termodinâmica , Proteínas do Envelope Viral/antagonistas & inibidores , Proteínas do Envelope Viral/metabolismo
13.
Sci Rep ; 11(1): 11562, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34079010

RESUMO

The Sec61 complex translocates nascent polypeptides into and across the membrane of the endoplasmic reticulum (ER), providing access to the secretory pathway. In this study, we show that Ipomoeassin-F (Ipom-F), a selective inhibitor of protein entry into the ER lumen, blocks the in vitro translocation of certain secretory proteins and ER lumenal folding factors whilst barely affecting others such as albumin. The effects of Ipom-F on protein secretion from HepG2 cells are twofold: reduced ER translocation combined, in some cases, with defective ER lumenal folding. This latter issue is most likely a consequence of Ipom-F preventing the cell from replenishing its ER lumenal chaperones. Ipom-F treatment results in two cellular stress responses: firstly, an upregulation of stress-inducible cytosolic chaperones, Hsp70 and Hsp90; secondly, an atypical unfolded protein response (UPR) linked to the Ipom-F-mediated perturbation of ER function. Hence, although levels of spliced XBP1 and CHOP mRNA and ATF4 protein increase with Ipom-F, the accompanying increase in the levels of ER lumenal BiP and GRP94 seen with tunicamycin are not observed. In short, although Ipom-F reduces the biosynthetic load of newly synthesised secretory proteins entering the ER lumen, its effects on the UPR preclude the cell restoring ER homeostasis.


Assuntos
Glicoconjugados/farmacologia , Biossíntese de Proteínas/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Células Hep G2 , Humanos , Transporte Proteico , Canais de Translocação SEC/metabolismo
14.
Chem Rec ; 21(11): 3029-3048, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34047444

RESUMO

There is an increasing demand for significant amount of carbohydrate-containing molecules owing to their complete chemical, biological, and pharmacological investigations to better understand their role in many important biological events. Clinical studies of a wide range of simple carbohydrates or their derivatives, glycohybrids, glycoconjugates, and neoglycoconjugates have been conducted worldwide for the successful treatment of various frontline diseases. Herein, a brief perspective of carbohydrate-based molecular scaffolding and my experience during the last 20 years in the area of synthetic carbohydrate chemistry, mainly for their impact in drug discovery & development, is presented.


Assuntos
Carboidratos , Glicoconjugados , Descoberta de Drogas
15.
Eur J Med Chem ; 220: 113472, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-33940463

RESUMO

A total of forty-three compounds were synthesized, including thirty-two new ones. Among those compounds, seventeen were selected and tested on human tumor cell lines: PC-3 (prostate adenocarcinoma), HCT-116 (colorectal tumor), NCIH-460 (lung carcinoma), SKMEL-103 (melanoma) and AGP-01 (gastric tumor). Alkynylated 1,2,4-oxadiazoles 2m, 3g and 3k exhibited antiproliferative activities against NCIH-460 in culture. Alkynylated N-cyclohexyl-1,2,4-oxadiazoles 3a-m and bis-heterocycle glucoglycero-1,2,3-triazole-N-cyclohexyl-1,2,4-oxadiazole derivatives 5a-k and 6-11 were evaluated for their in vitro efficacy towards Mycobacterium tuberculosis (Mtb) H37Ra and H37Rv strains. In general, glycerosugars conjugated to 1,2,4-oxadiazole via a 1,2,3-triazole linkage (5a, 5e, 5j, 5k, and 7) showed in vitro inhibitory activity against Mtb (H37Rv). The largest molecules bis-triazoles 10 and 11, proved inactive against TB. Probably, the absence of the N-cyclohexyl group in compound 8 and 1,2,4-oxadiazole nucleus in compound 9 were responsible for its low activity. Glucoglycero-triazole-oxadiazole derivatives 5e (10 µM) and 7 (23.9 µM) were the most promising antitubercular compounds, showing a better selective index than when tested against RAW 264.7 and HepG2 cells. Vero cell were used to investigate cytotoxicity of compounds 5a, 5h, 5j, 5k, and these compounds showed good cell viability. Further, in silico studies were performed for most active compounds (5e and 7) with potential drug targets, DprE1 and InhA of Mtb to understand possible interactions aided with molecular dynamic simulation (100ns).


Assuntos
Antineoplásicos/farmacologia , Antituberculosos/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Glicoconjugados/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Mycobacterium tuberculosis/efeitos dos fármacos , Oxidiazóis/química , Alcinos/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antituberculosos/síntese química , Antituberculosos/química , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Descoberta de Drogas , Glicoconjugados/síntese química , Glicoconjugados/química , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/química
16.
Front Cell Infect Microbiol ; 11: 671913, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34055669

RESUMO

Carbohydrates or glycans are ubiquitous components of the cell surface which play crucial biological and structural roles. Sialic acids (Sias) are nine-carbon atoms sugars usually present as terminal residues of glycoproteins and glycolipids on the cell surface or secreted. They have important roles in cellular communication and also in infection and survival of pathogens. More than 20 pathogens can synthesize or capture Sias from their hosts and incorporate them into their own glycoconjugates and derivatives. Sialylation of pathogens' glycoconjugates may be crucial for survival inside the host for numerous reasons. The role of Sias in protozoa such as Trypanosoma and Leishmania was demonstrated in previous studies. This review highlights the importance of Sias in several pathogenic infections, focusing on Leishmania. We describe in detail the contributions of Sias, Siglecs (sialic acid binding Ig-like lectins) and Neuraminidase 1 (NEU 1) in the course of Leishmania infection. A detailed view on the structural and functional diversity of Leishmania-related Sias and host-cell receptors will be provided, as well as the results of functional studies performed with different Leishmania species.


Assuntos
Leishmania , Leishmaniose , Glicoconjugados , Humanos , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico , Ácidos Siálicos
17.
Food Chem ; 361: 130143, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34051596

RESUMO

We previously observed that sialylated bovine milk oligosaccharides (BMOs) decline in both absolute and relative abundances over the initial stages of bovine lactation, with initial evidence suggesting that this decline occurred due to increased concentrations of unique sulfated BMOs. Since both sulfated and sialylated BMOs have distinct bioactivites, a follow up study was launched in order to more clearly define relative changes in these classes of BMOs over the first week of lactation in dairy cattle. Capillary electrophoresis (CE) and several liquid chromatography mass spectrometry (LC-MS) methods, including a novel multiplexed tandem MS method, were used to profile the BMOs extracted from milk collected from the same 20 Holstein cows at milkings 1, 2, 3, 4, 8, and 14 post-partum. In addition to clearly validating that sulfated and sialylated BMOs exist in direct biosynthetic completion, our study has identified over 170 unique BMOs including 14 unique glucuronic acid-containing trisaccharides.


Assuntos
Leite/química , Oligossacarídeos/biossíntese , Oligossacarídeos/química , Animais , Bovinos , Cromatografia Líquida , Eletroforese Capilar , Feminino , Ácido Glucurônico/análise , Ácido Glucurônico/química , Ácido Glucurônico/metabolismo , Glicoconjugados/química , Glicoconjugados/metabolismo , Lactação , Espectrometria de Massas , Leite/metabolismo , Ácido N-Acetilneuramínico/análise , Ácido N-Acetilneuramínico/metabolismo , Oligossacarídeos/análise , Oligossacarídeos/metabolismo , Sulfatos/química
18.
Int J Mol Sci ; 22(6)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805843

RESUMO

α-Synuclein (α-Syn) protein is involved in the pathogenesis of Parkinson's disease (PD). Point mutations and multiplications of the α-Syn, which encodes the SNCA gene, are correlated with early-onset PD, therefore the reduction in a-Syn synthesis could be a potential therapy for PD if delivered to the key affected neurons. Several experimental strategies for PD have been developed in recent years using oligonucleotide therapeutics. However, some of them have failed or even caused neuronal toxicity. One limiting step in the success of oligonucleotide-based therapeutics is their delivery to the brain compartment, and once there, to selected neuronal populations. Previously, we developed an indatraline-conjugated antisense oligonucleotide (IND-1233-ASO), that selectively reduces α-Syn synthesis in midbrain monoamine neurons of mice, and nonhuman primates. Here, we extended these observations using a transgenic male mouse strain carrying both A30P and A53T mutant human α-Syn (A30P*A53T*α-Syn). We found that A30P*A53T*α-Syn mice at 4-5 months of age showed 3.5-fold increases in human α-Syn expression in dopamine (DA) and norepinephrine (NE) neurons of the substantia nigra pars compacta (SNc) and locus coeruleus (LC), respectively, compared with mouse α-Syn levels. In parallel, transgenic mice exhibited altered nigrostriatal DA neurotransmission, motor alterations, and an anxiety-like phenotype. Intracerebroventricular IND-1233-ASO administration (100 µg/day, 28 days) prevented the α-Syn synthesis and accumulation in the SNc and LC, and recovered DA neurotransmission, although it did not reverse the behavioral phenotype. Therefore, the present therapeutic strategy based on a conjugated ASO could be used for the selective inhibition of α-Syn expression in PD-vulnerable monoamine neurons, showing the benefit of the optimization of ASO molecules as a disease modifying therapy for PD and related α-synucleinopathies.


Assuntos
Glicoconjugados/genética , Oligonucleotídeos Antissenso/administração & dosagem , Doença de Parkinson/terapia , Mutação Puntual , alfa-Sinucleína/antagonistas & inibidores , alfa-Sinucleína/genética , Substituição de Aminoácidos , Animais , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Glicoconjugados/administração & dosagem , Glicoconjugados/metabolismo , Humanos , Indanos/administração & dosagem , Indanos/química , Indanos/metabolismo , Injeções Intraventriculares , Locus Cerúleo/metabolismo , Locus Cerúleo/patologia , Masculino , Mesencéfalo/metabolismo , Mesencéfalo/patologia , Metilaminas/administração & dosagem , Metilaminas/química , Metilaminas/metabolismo , Camundongos , Camundongos Transgênicos , Norepinefrina/metabolismo , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Parte Compacta da Substância Negra/metabolismo , Parte Compacta da Substância Negra/patologia , Transmissão Sináptica , alfa-Sinucleína/metabolismo
19.
Molecules ; 26(9)2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33925409

RESUMO

A simple and efficient route for the synthesis of new glycoconjugates has been developed. The approach acts as a model for a mini-library of compounds with a deoxy-selenosugar core joined to a polyphenolic moiety with well-known antioxidant properties. An unexpected stereocontrol detected in the Mitsunobu key reaction led to the most attractive product showing a natural d-configuration. Thus, we were able to obtain the target molecules from the commercially available d-ribose via a shorter and convenient sequence of reactions.


Assuntos
Antioxidantes/síntese química , Glicoconjugados/síntese química , Compostos Organosselênicos/síntese química , Selênio/química , Antioxidantes/química , Glicoconjugados/química , Humanos , Compostos Organosselênicos/química
20.
Molecules ; 26(9)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33921945

RESUMO

Glycodendrimers have attracted considerable interest in the field of dendrimer sciences owing to their plethora of implications in biomedical applications. This is primarily due to the fact that cell surfaces expose a wide range of highly diversified glycan architectures varying by the nature of the sugars, their number, and their natural multiantennary structures. This particular situation has led to cancer cell metastasis, pathogen recognition and adhesion, and immune cell communications that are implicated in vaccine development. The diverse nature and complexity of multivalent carbohydrate-protein interactions have been the impetus toward the syntheses of glycodendrimers. Since their inception in 1993, chemical strategies toward glycodendrimers have constantly evolved into highly sophisticated methodologies. This review constitutes the first part of a series of papers dedicated to the design, synthesis, and biological applications of heterofunctional glycodendrimers. Herein, we highlight the most common synthetic approaches toward these complex molecular architectures and present modern applications in nanomolecular therapeutics and synthetic vaccines.


Assuntos
Técnicas de Química Sintética , Dendrímeros/química , Dendrímeros/farmacologia , Desenho de Fármacos , Glicoconjugados/química , Glicoconjugados/farmacologia , Carboidratos/química , Dendrímeros/síntese química , Desenvolvimento de Medicamentos , Glicoconjugados/síntese química , Humanos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Terapia de Alvo Molecular , Relação Estrutura-Atividade
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