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1.
ChemMedChem ; : e202300728, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38757641

RESUMO

Synthesis of non-platinum transition metal complexes with N,O donor chelating  ligand for application  against cancer with higher efficacy and selectivity is currently an important research field. We assessed The anti-cancer effects of a mixed ligand Ni(II) complex on human breast and lung cancer cell lines in the current investigation. Mononuclear mixed ligand octahedral Ni(II) complex [NiIIL(NO3)(MeOH)] complex(1), with tri-dentate phenol-based ligand 2,4-dichloro-6-((4-methylpiperazin-1-yl)methyl)phenol (HL) along with  methanol  and nitrate as ancillary ligand was prepared.  Piperazine moiety of the ligand exists as boat conformation in this complex as revealed from single crystal X-ray study. UV -visible spectrum of complex (1) exhibits three distinct d-d bands due to spin-allowed 3A2g→3T1g(P), 3A2g→3T1g(F) and 3A2g→3T2g(F) transitions as expected octahedral d8 system. Complex (1) through transactivation of p53 and its pro-apoptotic downstream targets induce apoptotic cell death in mouse and human cancer cells such as mcf-7, A549 and MDA-MB-231 in dose dependent manner. Furthermore, complex (1) was able to slow the migratory rate of MDA-MB-231 cells' in vitro as well as epithelia -mesenchymal transition (EMT), the key step for metastatic transition and malignancy. Over all our results suggest complex (1) as potential agent in anti-tumor treatment regimen both as cytotoxic and anti-metastatic agent against malignant neoplasia.

2.
J Biomed Sci ; 31(1): 43, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649998

RESUMO

Dengue viruses (DENV) are positive-stranded RNA viruses belonging to the Flaviviridae family. DENV is the causative agent of dengue, the most rapidly spreading viral disease transmitted by mosquitoes. Each year, millions of people contract the virus through bites from infected female mosquitoes of the Aedes species. In the majority of individuals, the infection is asymptomatic, and the immune system successfully manages to control virus replication within a few days. Symptomatic individuals may present with a mild fever (Dengue fever or DF) that may or may not progress to a more critical disease termed Dengue hemorrhagic fever (DHF) or the fatal Dengue shock syndrome (DSS). In the absence of a universally accepted prophylactic vaccine or therapeutic drug, treatment is mostly restricted to supportive measures. Similar to many other viruses that induce acute illness, DENV has developed several ways to modulate host metabolism to create an environment conducive to genome replication and the dissemination of viral progeny. To search for new therapeutic options, understanding the underlying host-virus regulatory system involved in various biological processes of the viral life cycle is essential. This review aims to summarize the complex interaction between DENV and the host cellular machinery, comprising regulatory mechanisms at various molecular levels such as epigenetic modulation of the host genome, transcription of host genes, translation of viral and host mRNAs, post-transcriptional regulation of the host transcriptome, post-translational regulation of viral proteins, and pathways involved in protein degradation.


Assuntos
Vírus da Dengue , Dengue , Vírus da Dengue/fisiologia , Vírus da Dengue/patogenicidade , Vírus da Dengue/genética , Humanos , Dengue/virologia , Animais , Interações Hospedeiro-Patógeno , Replicação Viral
3.
J Phys Chem B ; 128(13): 3133-3144, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38512319

RESUMO

The ionization state of amino acids on the outer surface of a virus regulates its physicochemical properties toward the sorbent surface. Serologically different strains of the dengue virus (DENV) show different extents of infectivity depending upon their interactions with a receptor on the host cell. To understand the structural dependence of E-protein protonation over its sequence dependence, we have followed E-protein titration kinetics both experimentally and theoretically for two differentially infected dengue serotypes, namely, DENV-2 and DENV-4. We have performed E-protein protonation titration-induced single-particle chemical force spectroscopy using an atomic force microscope (AFM) to measure the surface chemistry of DENV in physiological aqueous solutions not only to understand the charge distribution dynamics on the virus surface but also to estimate the isoelectric point (pI) accurately for infectious dengue viruses. Cryo-EM structure-based theoretical pI calculations of the DENV-2 surface protein were shown to be consistent with the evaluated pI value from force spectroscopy measurements. We also highlighted here the role of the microenvironment around the titrable residues (in the 3D-folded structure of the protein) in altering the pKa. This is a comprehensive study to understand how the cumulative charge distribution on the outer surface of a specific serotype of DENV regulates a prominent role of infectivity over minute changes at the genetic level.


Assuntos
Vírus da Dengue , Dengue , Humanos , Dengue/metabolismo
4.
J Leukoc Biol ; 115(5): 958-984, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38236200

RESUMO

Myeloid-derived suppressor cells are heterogenous immature myeloid lineage cells that can differentiate into neutrophils, monocytes, and dendritic cells as well. These cells have been characterized to have potent immunosuppressive capacity in neoplasia and a neoplastic chronic inflammatory microenvironment. Increased accumulation of myeloid-derived suppressor cells was reported with poor clinical outcomes in patients. They support neoplastic progression by abrogating antitumor immunity through inhibition of lymphocyte functions and directly by facilitating tumor development. Yet the shifting genetic signatures of this myeloid lineage cell toward immunosuppressive functionality in progressive tumor development remain elusive. We have attempted to identify the gene expression profile using lineage-specific markers of these unique myeloid lineage cells in a tumor microenvironment and bone marrow using a liquid transplantable mice tumor model to trace the changing influence of the tumor microenvironment on myeloid-derived suppressor cells. We analyzed the phenotype, functional shift, suppressive activity, differentiation status, and microarray-based gene expression profile of CD11b+Gr1+ lineage-specific cells isolated from the tumor microenvironment and bone marrow of 4 stages of tumor-bearing mice and compared them with control counterparts. Our analysis of differentially expressed genes of myeloid-derived suppressor cells isolated from bone marrow and the tumor microenvironment reveals unique gene expression patterns in the bone marrow and tumor microenvironment-derived myeloid-derived suppressor cells. It also suggests T-cell suppressive activity of myeloid-derived suppressor cells progressively increases toward the mid-to-late phase of the tumor and a significant differentiation bias of tumor site myeloid-derived suppressor cells toward macrophages, even in the presence of differentiating agents, indicating potential molecular characteristics of myeloid-derived suppressor cells in different stages of the tumor that can emerge as an intervention target.


Assuntos
Diferenciação Celular , Progressão da Doença , Células Supressoras Mieloides , Microambiente Tumoral , Animais , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/metabolismo , Células Supressoras Mieloides/patologia , Microambiente Tumoral/imunologia , Camundongos , Regulação Neoplásica da Expressão Gênica , Perfilação da Expressão Gênica , Camundongos Endogâmicos C57BL , Células da Medula Óssea/metabolismo , Antígeno CD11b/metabolismo , Antígeno CD11b/genética , Medula Óssea/patologia , Medula Óssea/metabolismo
5.
RNA Biol ; 20(1): 805-816, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37796112

RESUMO

DENV infection poses a major health concern globally and the pathophysiology relies heavily on host-cellular machinery. Although virus replication relies heavily on the host, the mechanistic details of DENV-host interaction is not fully characterized yet. Here, we are focusing on characterizing the mechanistic basis of virus-induced stress on the host cell. Specifically, we aim to characterize the role of the stress modulator ribonuclease Angiogenin during DENV infection. Our results suggested that the levels of Angiogenin are up-regulated in DENV-infected cells and the levels increase proportionately with DENV replication. Our efforts to knockdown Angiogenin using siRNA were unsuccessful in DENV-infected cells but not in mock-infected control. To further investigate the modulation between DENV replication and Angiogenin, we treated Huh7 cells with Ivermectin prior to DENV infection. Our results suggest a significant reduction in DENV replication specifically at the later stages as a consequence of Ivermectin treatment. Interestingly, Angiogenin levels were also found to be decreased proportionately. Our results suggest that Angiogenin modulation during DENV infection is important for DENV replication and pathogenesis.


Assuntos
Dengue , Ivermectina , Humanos , Ivermectina/farmacologia , Ribonuclease Pancreático/genética , Replicação Viral
6.
Chemistry ; 29(70): e202302529, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-37846644

RESUMO

We showed solvent- and concentration-triggered chiral tuning of the fibrous assemblies of two novel glycoconjugates Z-P(Gly)-Glu and Z-F(4-N)-Glu made by chemical attachment of Cbz-protected [short as Z)] non-proteinogenic amino acids L-phenylglycine [short as P(Gly)] and 4-Nitro-L-phenylalanine [short as F(4-N)] with D-glucosamine [short as Glu]. Both biomimetic gelators can form self-healing and shape-persistent gels with a very low critical gelator concentration in water as well as in various organic solvents, indicating they are ambidextrous supergelators. Detailed spectroscopic studies suggested ß-sheet secondary structure formation during anisotropic self-aggregation of the gelators which resulted in the formation of hierarchical left-handed helical fibers in acetone with an interlayer spacing of 2.4 nm. After the physical characterization of the gels, serum protein interaction with the gelators was assessed, indicating they may be ideal for biomedical applications. Further, both gelators are benign, non-immunogenic, non-allergenic, and non-toxic in nature, which was confirmed by performing the blood parameters and liver function tests on Wister rats. Streptomycin-loaded hydrogels showed efficacious antibacterial activity in vitro and in vivo as well. Finally, cell attachment and biocompatibility of the hydrogels were demonstrated which opens a newer avenue for promising biomedical and therapeutic applications.


Assuntos
Aminoácidos , Estreptomicina , Ratos , Animais , Aminoácidos/química , Solventes/química , Ratos Wistar , Hidrogéis/química
7.
Phytomedicine ; 119: 155007, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37549537

RESUMO

BACKGROUND: 1-2.88% of human populations are affected by psoriasis, one type of chronic inflammatory skin disease. Skin thickenings, erythema, scaling in skin are the most important symptoms of psoriasis. There are renewed interests amongst scientists in studying anti-inflammatory property of the plant extracts due to lower side effects and cost effectiveness. There are few reports suggesting anti-inflammatory activity of Premna herbacea roxb. but lacks systematic evaluation of these properties. METHODS: We, initially tested the anti-inflammatory activity of crude root methanolic extract in vitro, where it significantly reduced LPS generated ROS in splenic macrophages. We further tested the TLC and HPLC fraction in order to find active ingredient in Premna herbacea roxb. root extract that ameliorated the chronic inflammation of skin and performed GC-MS and LC-MS studies to identify active component. Upon finding significant anti-inflammatory effect of the crude root extract in vitro, We studied the efficacy of the Premna herbacea roxb. root extract in Imiquimod induced psoriasis like skin inflammation in male BALB/C mice that closely resembles human psoriasis. Immunophenotyping, Cytokine productions were observed by flow cytometry, status of gene expression was done by Real time PCR and nuclear co-localization was studied by confocal microscopy. RESULTS: We observed progressive increase in signs and symptoms of the disease in imiquimod treated diseased animals but the Premna herbacea roxb. Root Methanolic Extract (PHRME) reduced the thickening of the skin, redness and scaling in these animals. In our study, along with progression of the disease, the production of macrophages increases and with the application of PHRME, the percentage of macrophages have reduced. CONCLUSION: As per the previous Indigenous traditional knowledge regarding use of Premna herbacea roxb. against inflammatory disorder and lack of detail mechanistic study of the crude root extract prompted us to elucidate the efficacy of the root extract in vitro and in vivo psoriatic mice model. For the first time we have identified three putative bioactive active components (5­hydroxy-7-methoxyflavanone, 3-Hydroxy-7,8,2',3'-tetramethoxyflavone, 2,4',6'-trimethoxy chalcone) from Premna herbacea root methanolic extract (PHRME) and we suggest PHRME and purified active fractions influence NFκB and COX2 signaling pathway to suppress inflammatory conditions. All of the purified components show strong binding efficiency in our molecular docking analysis. Our study also suggests that Premna herbacea roxb. root extract may be explored as cost effective alternative for established treatment regimen as our study also indicates low side effect of the extract against pre-clinical psoriatic model.


Assuntos
Psoríase , Camundongos , Humanos , Animais , Imiquimode , Simulação de Acoplamento Molecular , Camundongos Endogâmicos BALB C , Psoríase/induzido quimicamente , Psoríase/tratamento farmacológico , Pele , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Macrófagos/metabolismo , Modelos Animais de Doenças , Citocinas/metabolismo
8.
Adv Virol ; 2023: 2995443, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37065904

RESUMO

SARS-CoV-2 is a novel coronavirus that causes a potentially fatal respiratory disease known as coronavirus disease (COVID-19) and is responsible for the ongoing pandemic with increasing mortality. Understanding the host-virus interaction involved in SARS-CoV-2 pathophysiology will enhance our understanding of the mechanistic basis of COVID-19 infection. The characterization of post-transcriptional gene regulatory networks, particularly pre-mRNA splicing, and the identification and characterization of host proteins interacting with the 5' and 3'UTRs of SARS-CoV-2 will improve our understanding of post-transcriptional gene regulation during SARS-CoV-2 pathogenesis. Here, we demonstrate that either SARS-CoV-2 infection or exogenous overexpression of the 5' and 3'UTRs of the viral genomic RNAs, results in reduced mRNA levels possibly due to modulation of host cell pre-mRNA splicing. Further, we have investigated the potential RNA-binding proteins interacting with the 5' and 3'UTRs, using in-silico approaches. Our results suggest that 5' and 3'UTRs indeed interact with many RNA-binding proteins. Our results provide a primer for further investigations into the UTR-mediated regulation of splicing and related molecular mechanisms in host cells.

9.
Reprod Toxicol ; 117: 108361, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36907498

RESUMO

Immunofluorescence techniques have been a great tool to chase the structure, localization, and function of many proteins within a cell. Drosophila eye is widely used as a model to answer various questions. However, the complex sample preparation and visualization methods restrict its use only with an expert's hand. Thus, an easy and hassle-free method is in need to broaden the use of this model even with an amateur's hand. The current protocol describes an easy sample preparation method using DMSO to image the adult fly eye. The brief description of sample collection, preparation, dissection, staining, imaging, storage, and handling has been described over here. For readers, the possible problems that might arise during the execution of the experiment have been described with their possible reason and solutions. The overall protocol reduces the use of chemicals and shortens the sample preparation time to only 3 h, which is significantly less in comparison to other protocols.


Assuntos
Dissecação , Drosophila , Animais , Drosophila/fisiologia , Dissecação/métodos , Crioultramicrotomia , Olho
10.
Bioorg Chem ; 131: 106277, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36444792

RESUMO

A series of thiazole linked Oxindole-5-Sulfonamide (OSA) derivatives were designed as inhibitors of RNA-dependent RNA polymerase (RdRp) activity of Dengue virus. These were synthesized and then evaluated for their efficacy in ex-vivo virus replication assay using human cell lines. Among 20 primary compounds in the series, OSA-15 was identified as a hit. A series of analogues were synthesized by replacing the difluoro benzyl group of OSA-15 with different substituted benzyl groups. The efficacy of OSA-15derivatives was less than that of the parent compound, except OSA-15-17, which has shown improved efficacy than OSA-15. The further optimization was carried out by adding dimethyl (DM) groups to both the sulfonamide and oxindole NH's to produce OSA-15-DM and OSA-15-17-DM. These two compounds were showing no detectable cytotoxicity and the latter was more efficacious. Further, both these compounds were tested for inhibition in all the serotypes of the Dengue virus using an ex-vivo assay. The EC50 of OSA-15-17-DM was observed in a low micromolar range between 2.5 and 5.0 µg/ml. Computation docking and molecular dynamics simulation studies confirmed the binding of identified hits to DENV RdRp. OSA15-17-DM blocks the RNA entrance and elongation site for their biological activity with high binding affinity. Overall, the identified oxindole derivatives are novel compounds that can inhibit Dengue replication, working as non-nucleoside inhibitors (NNI) to explore as anti-viral RdRp activity.


Assuntos
Antivirais , Dengue , Oxindóis , Antivirais/química , Dengue/tratamento farmacológico , Vírus da Dengue , Simulação de Acoplamento Molecular , Oxindóis/farmacologia , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Sulfonamidas/farmacologia
11.
Int Immunopharmacol ; 114: 109521, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36470118

RESUMO

In clinical practice, major efforts are underway to identify appropriate drug combinations to boost anticancer activity while suppressing unwanted adverse effects. In this regard, we evaluated the efficacy of combination treatment with the widely used chemotherapeutic drug doxorubicin along with the TGFßRI inhibitor galunisertib (LY2157299) in aggressive B-cell non-Hodgkin lymphoma (B-NHL). The antiproliferative effects of these drugs as single agents or in combination against several B-NHL cell lines and the synergism of the drug combination were evaluated by calculating the combination index. To understand the putative molecular mechanism of drug synergism, the TGF-ß and stress signaling pathways were analyzed after combination treatment. An aggressive lymphoma model was used to evaluate the anticancer activity and post-therapeutic immune response of the drug combination in vivo. Galunisertib sensitized various B-NHL cells to doxorubicin and in combination synergistically increased apoptosis. The antitumor activity of the drug combinations involved upregulation of p-P38 MAPK and inhibition of the TGF-ß/Smad2/3 and PI3K/AKT signaling pathways. Combined drug treatment significantly reduced tumor growth and enhanced survival, indicating that the synergism between galunisertib and Dox observed in vitro was most likely retained in vivo. Based on the tumor-draining lymph node analysis, combination therapy results in better prognosis, including disappearance of disease-exacerbating regulatory T cells and prevention of CD8+ T-cell exhaustion by downregulating MDSCs. Galunisertib synergistically potentiates the doxorubicin-mediated antitumor effect without aggravating the toxic effects and the ability to kickstart the immune system, supporting the clinical relevance of targeting TGF-ßRI in combination with doxorubicin against lymphoma.


Assuntos
Linfoma , Neoplasias , Humanos , Fosfatidilinositol 3-Quinases/farmacologia , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Neoplasias/tratamento farmacológico , Fator de Crescimento Transformador beta , Sistema Imunitário , Sinergismo Farmacológico , Linhagem Celular Tumoral , Apoptose
12.
Cancer Immunol Res ; 11(3): 364-380, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36574614

RESUMO

B cells are an essential component of humoral immunity. Their primary function is to mount antigen-specific antibody responses to eliminate pathogens. Despite an increase in B-cell number, we found that serum-IgG levels were low in patients with breast cancer. To solve this conundrum, we used high-dimensional flow cytometry to analyze the heterogeneity of B-cell populations and identified a tumor-specific CD19+CD24hiCD38hi IL10-producing B regulatory (Breg)-cell subset. Although IL10 is a Breg-cell marker, being an intracellular protein, it is of limited value for Breg-cell isolation. Highly expressed Breg-cell surface proteins CD24 and CD38 also impede the isolation of viable Breg cells. These are hurdles that limit understanding of Breg-cell functions. Our transcriptomic analysis identified, CD39-negativity as an exclusive, sorting-friendly surface marker for tumor-associated Breg cells. We found that the identified CD19+CD39‒IL10+ B-cell population was suppressive in nature as it limited T helper-cell proliferation, type-1 cytokine production, and T effector-cell survival, and augmented CD4+FOXP3+ regulatory T-cell generation. These tumor-associated Breg cells were also found to restrict autologous T follicular helper-cell expansion and IL21 secretion, thereby inhibiting germinal transcript formation and activation-induced cytidine deaminase expression involved in H-chain class-switch recombination (CSR). This isotype-switching abnormality was shown to hinder B-cell differentiation into class-switched memory B cells and subsequent high-affinity antibody-producing plasma B cells, which collectively led to the dampening of IgG-mediated antibody responses in patients with cancer. As low IgG is associated with poor prognosis in patients with cancer, Breg-cell depletion could be a promising future therapy for boosting plasma B cell-mediated antibody responses.


Assuntos
Interleucina-10 , Neoplasias , Humanos , Formação de Anticorpos , Antígenos CD19 , Linfócitos T CD4-Positivos , Imunoglobulina G
13.
PLoS Pathog ; 18(12): e1010994, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36508467

RESUMO

The emergence of new variants of SARS-CoV-2 necessitates unremitting efforts to discover novel therapeutic monoclonal antibodies (mAbs). Here, we report an extremely potent mAb named P4A2 that can neutralize all the circulating variants of concern (VOCs) with high efficiency, including the highly transmissible Omicron. The crystal structure of the P4A2 Fab:RBD complex revealed that the residues of the RBD that interact with P4A2 are a part of the ACE2-receptor-binding motif and are not mutated in any of the VOCs. The pan coronavirus pseudotyped neutralization assay confirmed that the P4A2 mAb is specific for SARS-CoV-2 and its VOCs. Passive administration of P4A2 to K18-hACE2 transgenic mice conferred protection, both prophylactically and therapeutically, against challenge with VOCs. Overall, our data shows that, the P4A2 mAb has immense therapeutic potential to neutralize the current circulating VOCs. Due to the overlap between the P4A2 epitope and ACE2 binding site on spike-RBD, P4A2 may also be highly effective against a number of future variants.


Assuntos
Enzima de Conversão de Angiotensina 2 , Anticorpos Neutralizantes , COVID-19 , SARS-CoV-2 , Animais , Humanos , Camundongos , Enzima de Conversão de Angiotensina 2/química , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , COVID-19/imunologia , COVID-19/terapia , Camundongos Transgênicos , Testes de Neutralização , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética
14.
3 Biotech ; 12(9): 202, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35928502

RESUMO

We used human semi-synthetic phage antibody gene libraries to select anti-SARS-CoV-2 RBD scFv antibody fragment and subsequent characterization of this novel tetravalent monoclonal antibody targeting conformational epitopes in the receptor binding domain of SARS-CoV-2. Binding studies suggest that II62 tetravalent antibody cross-reacts with RBD protein of SARS-CoV2 and its different variants of concerns. The epitope mapping data reveals that II62 tetravalent antibody targets an epitope that does not directly interferes with RBD: ACE2 interaction. Neutralization studies with live authentic SARS-CoV2 virus suggests that increase in valency of II62 mAb from monovalent to tetravalent doesn't perturbate virus interactions with the ACE2 expressing host cells in cytopathic effect-based (CPE) assay. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-022-03272-6.

15.
Anal Methods ; 14(33): 3196-3202, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-35938936

RESUMO

A new benzorhodol-based non-fluorescent organic frame (DEB-CO) detects carbon monoxide (CO) selectively through a spirolactam ring-opening mechanism. Herein, the selective off-on fluorogenic behavior of this probe towards CO has been achieved without any assistance of precious and hazardous metals (e.g. Pd2+) as additional substrates. Moreover, the red-emissive probe motivated us to apply in situ tracing in mice and living cells. The selective off-on fluorogenic behavior of this probe towards CO originating from CORM-3 in vitro and in vivo with a limit of detection as low as 64.29 nM (for CORM-3) has been observed. Additionally, this probe is capable of sensing toxic carbon monoxide gas. This probe has also been utilized to detect intracellular CO in MCF7 cells (in vitro) and to spot the distribution of CO in mice (in vivo) by acquiring bioimages with the help of confocal microscopy, which indicates that DEB-CO is a smart competent probe for this purpose.


Assuntos
Monóxido de Carbono , Corantes Fluorescentes , Animais , Humanos , Células MCF-7 , Metais , Camundongos , Microscopia Confocal
16.
Life Sci ; 305: 120755, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35780842

RESUMO

The tumor microenvironment is a complex domain that not only contains tumor cells but also a plethora of other host immune cells. By nature, the tumor microenvironment is a highly immunosuppressive milieu providing growing conditions for tumor cells. A major immune cell population that contributes most in the development of this immunosuppressive microenvironment is the MDSC, a heterogenous population of immature cells. Although found in small numbers only in the bone marrow of healthy individuals, they readily migrate to the lymph nodes and tumor site during cancer pathogenesis. MDSC mediated disruption of antitumor T cell activity is a major cause of the immunosuppression at the tumor site, but recent findings have shown that MDSC mediated dysfunction of other major immune cells might also play an important role. In this article we will review how crosstalk with MDSC alters the activity of both conventional and unconventional immune cells that inhibits the antitumor immunity and promotes cancer progression.


Assuntos
Células Supressoras Mieloides , Neoplasias , Humanos , Terapia de Imunossupressão , Neoplasias/patologia , Linfócitos T , Microambiente Tumoral
17.
Carbohydr Polym ; 291: 119614, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35698411

RESUMO

We report the solvent-free green synthesis of two Schiff bases, (E)-2-((2-hydroxy-3-methoxybenzylidene)amino)-4-methylphenol (SL1) and (E)-2-((2-hydroxybenzylidene) amino)-4-methylphenol (SL2), and their inclusion complexes with ß-cyclodextrin (ß-CD). The encapsulation phenomenon, structural characteristics and hydrolytic stabilities of the SL1, SL2 and their inclusion complexes are determined with a suite of spectroscopic, analytical and crystallographic analyses. Dose and time-dependent cytotoxicity study of SL1-ß-CD and SL2-ß-CD against two breast cancer cell lines, Michigan Cancer Foundation-7 (MCF-7) and metastatic mammary adenocarcinoma1 (MDA-MB-231), exhibit excellent inhibitory activity with significant non-cytotoxic concentrations and ensure a multifold elevation of bio-potency than the parent Schiff base compounds. The Annexin-V assay determines the efficacy of these inclusion complexes to trigger apoptosis, suggesting that SL2-ß-CD possesses better efficacy as an anti-cancer drug. To the best of our knowledge, we, for the first time, report the inclusion of nanocrystalline Schiff bases into ß-CD for multifold enrichment of bio-potency.


Assuntos
Antineoplásicos , beta-Ciclodextrinas , Antineoplásicos/química , Apoptose , Humanos , Células MCF-7 , Bases de Schiff/química , beta-Ciclodextrinas/farmacologia
18.
PLoS Pathog ; 18(4): e1010465, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35482816

RESUMO

Although efficacious vaccines have significantly reduced the morbidity and mortality of COVID-19, there remains an unmet medical need for treatment options, which monoclonal antibodies (mAbs) can potentially fill. This unmet need is exacerbated by the emergence and spread of SARS-CoV-2 variants of concern (VOCs) that have shown some resistance to vaccine responses. Here we report the isolation of five neutralizing mAbs from an Indian convalescent donor, out of which two (THSC20.HVTR04 and THSC20.HVTR26) showed potent neutralization of SARS-CoV-2 VOCs at picomolar concentrations, including the Delta variant (B.1.617.2). One of these (THSC20.HVTR26) also retained activity against the Omicron variant. These two mAbs target non-overlapping epitopes on the receptor-binding domain (RBD) of the spike protein and prevent virus attachment to its host receptor, human angiotensin converting enzyme-2 (hACE2). Furthermore, the mAb cocktail demonstrated protection against the Delta variant at low antibody doses when passively administered in the K18 hACE2 transgenic mice model, highlighting their potential as a cocktail for prophylactic and therapeutic applications. Developing the capacity to rapidly discover and develop mAbs effective against highly transmissible pathogens like coronaviruses at a local level, especially in a low- and middle-income country (LMIC) such as India, will enable prompt responses to future pandemics as an important component of global pandemic preparedness.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Camundongos , Glicoproteína da Espícula de Coronavírus
19.
Front Pharmacol ; 13: 852065, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35444547

RESUMO

Integrative medicine practices, such as Ayurveda, are popular in India and many South Asian countries, yet basic research to investigate the concepts, procedures, and medical benefits of ayurvedic products has received little attention and is not fully understood. Here, we report a functional nanodiamond-based traditional Ayurvedic herbomineral formulation, Heerak Bhasma (Ayu_ND), for the treatment of solid tumors called Dalton's lymphoma generated in CD1 mice. Ayu_ND-mediated immunostimulation significantly reduces tumor cell proliferation and induces apoptosis aided by the active participation of dendritic cells. Immunomodulatory Ayu_ND treatment is highly immunostimulatory and drives dendritic cells to produce TNF-α. Treatment with Ayu_ND significantly reduces the tumor volume, inhibits metastasis in distant vascularized organs, and increases the life span of tumor-bearing animals compared with untreated littermates. These events were associated with elevated serum levels of the protective cytokines IFN-γ and TNF-α and downregulated the disease, exacerbating TGF-ß. Ayu_ND-mediated therapeutic success was also accompanied by the depletion of regulatory T cells and enhanced vaccine-induced T-cell immunity, guided by the restoration of the memory CD8+ T-cell pool and prevention of PD-1-mediated T cell exhaustion. The results provide a basis for further evaluation of ayurvedic formulations and drug efficacy in treating cancers.

20.
Nat Commun ; 13(1): 1726, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35365648

RESUMO

Immunization is expected to confer protection against infection and severe disease for vaccines while reducing risks to unimmunized populations by inhibiting transmission. Here, based on serial serological studies of an observational cohort of healthcare workers, we show that during a Severe Acute Respiratory Syndrome -Coronavirus 2 Delta-variant outbreak in Delhi, 25.3% (95% Confidence Interval 16.9-35.2) of previously uninfected, ChAdOx1-nCoV19 double vaccinated, healthcare workers were infected within less than two months, based on serology. Induction of anti-spike response was similar between groups with breakthrough infection (541 U/ml, Inter Quartile Range 374) and without (342 U/ml, Inter Quartile Range 497), as was the induction of neutralization activity to wildtype. This was not vaccine failure since vaccine effectiveness estimate based on infection rates in an unvaccinated cohort were about 70% and most infections were asymptomatic. We find that while ChAdOx1-nCoV19 vaccination remains effective in preventing severe infections, it is unlikely to be completely able to block transmission and provide herd immunity.


Assuntos
Infecções Assintomáticas , COVID-19 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pessoal de Saúde , Humanos , Imunização , SARS-CoV-2 , Vacinação
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