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1.
Acta Parasitol ; 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38085461

RESUMO

PURPOSE: Leishmania causes multiple types of leishmaniasis in different parts of the world. It has a lack of metabolic machine to produce purine bases. Therefore, the parasite produces purine bases through the breakdown of nutritional nucleotides and it makes the nucleoside hydrolases (NHs) good drug targets. They have different substrate-preferring (SP) types. Our objectives were modeling and comparative analysis of these protein structures for Leishmania major. METHOD: In this work, available sequences for all SP types of L. major NH enzymes including inosine-uridine preferring NH (IUNH), inosine-guanosine preferring NH (IGNH), and inosine-adenosine-guanosine preferring NH (IAGNH) were used to make 24 structural models via SWISS-MODEL and LOMETS. After evaluating the structural models, three enzyme structures were finalized and used to analyze substrate-binding pockets. RESULTS: The three SP types of L. major NH enzymes that can breakdown purine nucleosides were highly different in terms of sequence, structure, and profile of interacting residues within the substrate-binding pockets. In this study, new enzyme structures have been presented for three SP types and they have been compared in different aspects and it indicated that they were very different from each other. CONCLUSION: Although, previously indicated that from these three SP types in genera other than Leishmania, the role of IGNH and IAGNH was greater than IUNH in supplying purine bases, till this work, just IUNH has been structurally studied and used in drug-design investigations for Leishmania. Therefore, we are offering to use all three SP types of NHs as multi-target strategy in anti-leishmaniosis drug-design studies.

2.
Clin Immunol ; 246: 109180, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36396013

RESUMO

Borrelia burgdorferi (Bb) infection causes Lyme disease, for which there is need for more effective therapies. Here, we sequenced the antibody repertoire of plasmablasts in Bb-infected humans. We expressed recombinant monoclonal antibodies (mAbs) representing the identified plasmablast clonal families, and identified their binding specificities. Our recombinant anti-Bb mAbs exhibit a range of activity in mediating macrophage phagocytosis of Bb. To determine if we could increase the macrophage phagocytosis-promoting activity of our anti-Bb mAbs, we generated a TLR9-agonist CpG-oligo-conjugated anti-BmpA mAb. We demonstrated that our CpG-conjugated anti-BmpA mAb exhibited increased peak Bb phagocytosis at 12-24 h, and sustained macrophage phagocytosis over 60+ hrs. Further, our CpG-conjugated anti-BmpA mAb induced macrophages to exhibit a sustained activation morphology. Our findings demonstrate the potential for TLR9-agonist CpG-oligo conjugates to enhance mAb-mediated clearance of Bb, and this approach might also enhance the activity of other anti-microbial mAbs.


Assuntos
Borrelia burgdorferi , Doença de Lyme , Humanos , Borrelia burgdorferi/metabolismo , Receptor Toll-Like 9/metabolismo , Macrófagos , Doença de Lyme/metabolismo , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/metabolismo
3.
Biomed Pharmacother ; 146: 112531, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34906771

RESUMO

Despite the promising medicinal properties, berberine (BBR), due to its relatively poor solubility in plasma, low bio-stability and limited bioavailability is not used broadly in clinical stages. Due to these drawbacks, drug delivery systems (DDSs) based on nanoscale natural polysaccharides, are applied to address these concerns. Natural polymers are biodegradable, non-immunogenic, biocompatible, and non-toxic agents that are capable of trapping large amounts of hydrophobic compounds in relatively small volumes. The use of nanoscale natural polysaccharide improves the stability and pharmacokinetics of the small molecules and, consequently, increases the therapeutic effects and reduces the side effects of the small molecules. Therefore, this paper presents an overview of the different methods used for increasing the BBR solubility and bioavailability. Afterwards, the pharmacodynamic and pharmacokinetic of BBR nanostructures were discussed followed by the introduction of natural polysaccharides of plant (cyclodextrines, glucomannan), the shells of crustaceans (chitosan), and the cell wall of brown marine algae (alginate)-based origins used to improve the dissolution rate of poorly soluble BBR and their anticancer and antibacterial properties. Finally, the anticancer and antibacterial mechanisms of free BBR and BBR nanostructures were surveyed. In conclusion, this review may pave the way for providing some useful data in the development of BBR-based platforms for clinical applications.


Assuntos
Berberina , Quitosana , Nanoestruturas , Antibacterianos/farmacologia , Berberina/química , Disponibilidade Biológica , Quitosana/química
4.
Life Sci ; 264: 118719, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33159957

RESUMO

AIM: As a natural compound, docosahexaenoic acid (DHA) exerts anti-cancer and anti-angiogenesis functions through exosomes; however, little is known about the molecular mechanisms. MAIN METHODS: Breast cancer (BC) cells were treated with DHA (50 µM) and then tumor cell-derived exosomes (TDEs) were collected and characterized by electron microscopy, dynamic light scattering, and western blot analyses. By the time the cells were treated with DHA, RT-qPCR was used to investigate the expression of vascular endothelial growth factor (VEGF) and the selected pro- and anti-angiogenic microRNAs (miRNAs). The quantification of secreted VEGF protein was measured by enzyme-linked immunosorbent assay (ELISA). The effects of TDEs on endothelial cell angiogenesis were explored by transwell cell migration and in vitro vascular tube formation assays. KEY FINDINGS: DHA treatment caused a significant and time-dependent decrease in the expression and secretion of VEGF in/from BC cells. This also increased expression of anti-angiogenic miRNAs (i.e. miR-34a, miR-125b, miR-221, and miR-222) while decreased levels of pro-angiogenic miRNAs (i.e. miR-9, miR-17-5p, miR-19a, miR-126, miR-130a, miR-132, miR-296, and miR-378) in exosomes derived from DHA-treated BC cells, TDE (DHA+). While treatment with exosomes (100 µg/ml) obtained from untreated BC cells, TDE (DHA-), enhanced the expression of VEGF-A in human umbilical vein endothelial cells (HUVECs), incubation with DHA or TDE (DHA+) led to the significant decrease of VEGF-A transcript level in these cells. We indicated that the incubation with TDE (DHA+) could significantly decrease endothelial cell proliferation and migration and also the length and number of tubes made by HUVECs in comparison with endothelial cells incubated with exosomes obtained from untreated BC cells. SIGNIFICANCE: DHA alters angiogenesis by shifting the up-regulation of exosomal miRNA contents from pro-angiogenic to anti-angiogenic, resulting in the inhibition of endothelial cell angiogenesis. These data can help to figure out DHA's anti-cancer function, maybe its use in cancer therapy.


Assuntos
Neoplasias da Mama/patologia , Movimento Celular/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/farmacologia , Exossomos/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Exossomos/efeitos dos fármacos , Exossomos/ultraestrutura , Feminino , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismo
5.
Int J Nanomedicine ; 14: 243-256, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30643404

RESUMO

BACKGROUND: Nanoparticles (NPs) have been emerging as potential players in modern medicine with clinical applications ranging from therapeutic purposes to antimicrobial agents. However, before applications in medical agents, some in vitro studies should be done to explore their biological responses. AIM: In this study, protein binding, anticancer and antibacterial activates of zero valent iron (ZVFe) were explored. MATERIALS AND METHODS: ZVFe nanoparticles were synthesized and fully characterized by X-ray diffraction, field-emission scanning electron microscope, and dynamic light scattering analyses. Afterward, the interaction of ZVFe NPs with human serum albumin (HSA) was examined using a range of techniques including intrinsic fluorescence, circular dichroism, and UV-visible spectroscopic methods. Molecular docking study was run to determine the kind of interaction between ZVFe NPs and HSA. The anticancer influence of ZVFe NPs on SH-SY5Y was examined by MTT and flow cytometry analysis, whereas human white blood cells were used as the control cell. Also, the antibacterial effect of ZVFe NPs was examined on Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922), and Staphylococcus aureus (ATCC 25923). RESULTS: X-ray diffraction, transmission electron microscope, and dynamic light scattering analyses verified the synthesis of ZVFe NPs in a nanosized diameter. Fluorescence spectroscopy analysis showed that ZVFe NPs spontaneously formed a complex with HSA through hydrogen bonds and van der Waals interactions. Also, circular dichroism spectroscopy study revealed that ZVFe NPs did not change the secondary structure of HSA. Moreover, UV-visible data presented that melting temperature (Tm) of HSA in the absence and presence of ZVFe NPs was almost identical. Molecular dynamic study also showed that ZVFe NP came into contact with polar residues on the surface of HSA molecule. Cellular assays showed that ZVFe NPs can induce cell mortality in a dose-dependent manner against SH-SY5Y cells, whereas these NPs did not trigger significant cell mortality against normal white bloods in the concentration range studied (1-100 µg/mL). Antibacterial assays showed a noteworthy inhibition on both bacterial strains. CONCLUSION: In conclusion, it was revealed that ZVFe NPs did not induce a substantial influence on the structure of protein and cytotoxicity against normal cell, whereas they derived significant anticancer and antibacterial effects.


Assuntos
Antibacterianos/administração & dosagem , Antineoplásicos/administração & dosagem , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Ferro/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Albumina Sérica Humana/metabolismo , Antibacterianos/química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Humanos , Ferro/química , Nanopartículas Metálicas/química , Simulação de Acoplamento Molecular , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Conformação Proteica , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/metabolismo , Albumina Sérica Humana/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/metabolismo , Células Tumorais Cultivadas
6.
J Cell Physiol ; 234(8): 13781-13787, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30671955

RESUMO

INTRODUCTION: The aim of this study was to evaluate the expression of IDO-1 gene and cancerous grades of non-small cell lung cancer (NSCLC) and its subclasses among patients with lung cancer using real-time polymerase chain reaction (PCR). MATERIALS AND METHODS: A total of 35 clinical samples were collected from patients with NSCLC. To evaluate the IDO-1 gene after the extraction of RNA and complementary DNA (cDNA) synthesis using real-time PCR, the expression of the gene was investigated. The western blot analysis method was used for protein expression. RESULTS: The highest grade, IIIa grade included six patients (17.1%). Approximately 74% of adenocarcinoma cases were in T-categories of lung cancer and 25% of patients in IIIa grade. Patients in the IIA and IIB categories belong to the SCC subclass. Results showed that the expression of INDO 5.22 fold gene was more common in patients with lung cancer than NSCLC. Protein expression in western blot analysis in patients compared with normal 3.22 fold change increased. CONCLUSION: The evidence shows that IDO-1 is a key parameter that inhibits antitumor immune responses in humans. This study has added interesting data to the IDO community for analyzing the expression of cancerous human cancer cells and cancer tissue in humans. The results showed that IDO-1 not only participates in the process of escape from tumor immunity but can also contribute to the safety of the pretumor area. A wide variety of observed IDO-1 expression values ​​among patients may present serious barriers to the clinical performance of anti- IDO strategies at present.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Indolamina-Pirrol 2,3,-Dioxigenase/biossíntese , Neoplasias Pulmonares/patologia , Transcriptoma , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Reação em Cadeia da Polimerase em Tempo Real
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