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1.
J Cell Physiol ; 234(5): 6951-6964, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30443899

RESUMO

In the recent past, various groups have proposed diverse biocompatible methods for the synthesis of metal nanoparticles (NPs). Besides culture biomass, culture supernatants (CS) are increasingly being explored for the synthesis of NPs; however, with the ever-increasing exploration of various CS in the biofabrication of NPs, it is equally important to explore the potential of various culture media (CMs) in the synthesis of metal NPs. Considering these aspects, in the present investigation, we explore the possible applicability of various CMs in the biofabrication of metal NPs. The synthesis of NPs was primarily followed by UV/VIS spectroscopy, and, thereafter, the NPs were characterized by various physiochemical techniques, including EM, EDX, FT_IR, X-ray diffraction, and DLS measurements, and finally, their anticancer potentialities were investigated against breast cancer. In addition, the NPs were examined in conjunction with artemisinin for therapeutic benefits against aggressive and highly metastatic MDA-MB-231 breast cancer cells. Cumulatively, the results of the present study collated the potentials of various bacterial CMs in the biofabrication of metal NPs and ascertained the efficacy of the as-synthesized silver nanoparticles, especially the combinatorial entity as intriguing breast cancer therapeutics. The data of the present study plausibly assist in advancing the therapeutic applicability of the combinatorial amalgam against aggressive and highly metastatic MDA-MB-231 breast cancer cells.


Assuntos
Artemisininas/química , Artemisininas/farmacologia , Bactérias/metabolismo , Neoplasias da Mama/tratamento farmacológico , Meios de Cultura/metabolismo , Nanopartículas Metálicas/química , Antineoplásicos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Células HEK293 , Humanos , Células MCF-7 , Tamanho da Partícula , Prata/química
2.
Nanomedicine ; 13(5): 1773-1783, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28216150

RESUMO

Commercially available amphotericin B (AmB) formulations are limited by cytotoxicities, lower efficacies, shelf-life related issues and high production costs. In this study, AmB complexes based on poly(gamma-glutamic acid) (PGGA) were prepared and evaluated for their efficacies against AmB-deoxycholate (Fungizone®) and liposomal AmB (AmBisome®). Physical characterizations showed that AmB/PGGA complexes are nanoscopic (20-40 nm) with a negative zeta potential (-45.5 to -51.0 mV), water-soluble, stable in solution (up to 4 weeks, at 4 °C and 25 °C), and have a high drug loading (up to 35% w/w). In vitro, AmB/PGGA complexes exhibited a more favorable cytotoxicity profile than Fungizone® but comparable to AmBisome®, with respect to the hemolytic activity and the modulation of pro-inflammatory cytokines (TNF-α and IL-1ß). In-vivo, AmB/PGGA complexes were significantly more efficacious than both Fungizone® and AmBisome® against experimental murine candidiasis. These results provide strong evidence that AmB/PGGA complexes display better efficacy and safety features than the currently approved AmB products.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Anfotericina B/administração & dosagem , Animais , Antifúngicos/administração & dosagem , Candidíase/tratamento farmacológico , Ácido Glutâmico , Camundongos , Nanotecnologia/métodos , Fator de Necrose Tumoral alfa
3.
J Biol Chem ; 290(7): 4131-48, 2015 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-25512377

RESUMO

Amyloids are highly organized protein aggregates that arise from inappropriately folded versions of proteins or polypeptides under both physiological as well as simulated ambiences. Once thought to be irreversible assemblies, amyloids have begun to expose their more dynamic and reversible attributes depending upon the intrinsic properties of the precursor protein/peptide and experimental conditions such as temperature, pressure, structural modifications in proteins, or presence of chemicals in the reaction mixture. It has been repeatedly proposed that amyloids undergo transformation to the bioactive peptide/protein forms under specific conditions. In the present study, amyloids assembled from the model protein ovalbumin (OVA) were found to release the precursor protein in a slow and steady manner over an extended time period. Interestingly, the released OVA from amyloid depot was found to exhibit biophysical characteristics of native protein and reacted with native-OVA specific monoclonal as well as polyclonal antibodies. Moreover, antibodies generated upon immunization of OVA amyloidal aggregates or fibrils were found to recognize the native form of OVA. The study suggests that amyloids may act as depots for the native form of the protein and therefore can be exploited as vaccine candidates, where slow antigen release over extended time periods is a pre-requisite for the development of desired immune response.


Assuntos
Amiloide/imunologia , Anticorpos Monoclonais/imunologia , Ovalbumina/imunologia , Peptídeos/imunologia , Linfócitos T/imunologia , Amiloide/química , Amiloide/metabolismo , Animais , Anticorpos Monoclonais/sangue , Dicroísmo Circular , Citocinas/metabolismo , Feminino , Imunização , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Óxido Nítrico/metabolismo , Ovalbumina/química , Ovalbumina/metabolismo , Peptídeos/química , Peptídeos/metabolismo , Conformação Proteica , Multimerização Proteica
4.
Comput Biol Chem ; 108: 107999, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38070457

RESUMO

Breast cancer continues to be a prominent cause for substantial loss of life among women globally. Despite established treatment approaches, the rising prevalence of breast cancer is a concerning trend regardless of geographical location. This highlights the need to identify common key genes and explore their biological significance across diverse populations. Our research centered on establishing a correlation between common key genes identified in breast cancer patients. While previous studies have reported many of the genes independently, our study delved into the unexplored realm of their mutual interactions, that may establish a foundational network contributing to breast cancer development. Machine learning algorithms were employed for sample classification and key gene selection. The best performance model further selected the candidate genes through expression pattern recognition. Subsequently, the genes common in all the breast cancer patients from India, China, Czech Republic, Germany, Malaysia and Saudi Arabia were selected for further study. We found that among ten classifiers, Catboost exhibited superior performance with an average accuracy of 92%. Functional enrichment analysis and pathway analysis revealed that calcium signaling pathway, regulation of actin cytoskeleton pathway and other cancer-associated pathways were highly enriched with our identified genes. Notably, we observed that these genes regulate each other, forming a complex network. Additionally, we identified PALMD gene as a novel potential biomarker for breast cancer progression. Our study revealed key gene modules forming a complex network that were consistently expressed in different populations, affirming their critical role and biological significance in breast cancer. The identified genes hold promise as prospective biomarkers of breast cancer prognosis irrespective of country of origin or ethnicity. Future investigations will expand upon these genes in a larger population and validate their biological functions through in vivo analysis.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama , Humanos , Feminino , Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Perfilação da Expressão Gênica , Biologia Computacional , Aprendizado de Máquina
5.
Nanomedicine ; 9(2): 247-56, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22858760

RESUMO

In the current study, a novel niosome based formulation of diallyl disulfide (DADS) was evaluated for its potential to treat disseminated candidiasis in mouse model. Among various non-ionic surfactants tested, niosome formulation prepared using Span 80 was found to be most efficient in the entrapment of DADS. The DADS loaded niosomes had size dimensions in the range of 140 ± 30 nm with zeta potential of -30.67 ± 4.5. Liver/kidney function tests as well as histopathologic studies suggested that noisome-based DADS formulations are safe at the dose investigated. When administered to Candida albicans infected animals, the DADS bearing niosomal formulation cleared the fungal burden and increased their survival much efficiently than its free form. FROM THE CLINICAL EDITOR: In this study, a novel niosomal formulation of the antifungal DADS was utilized in a murine candidiasis model, resulting in more efficient fungal clearance compared to the free formulation.


Assuntos
Compostos Alílicos/uso terapêutico , Antifúngicos/uso terapêutico , Candida albicans/efeitos dos fármacos , Candidíase/tratamento farmacológico , Dissulfetos/uso terapêutico , Portadores de Fármacos/química , Hexoses/química , Tensoativos/química , Compostos Alílicos/administração & dosagem , Compostos Alílicos/farmacocinética , Animais , Antifúngicos/administração & dosagem , Antifúngicos/farmacocinética , Dissulfetos/administração & dosagem , Dissulfetos/farmacocinética , Portadores de Fármacos/toxicidade , Feminino , Hexoses/toxicidade , Camundongos , Camundongos Endogâmicos BALB C , Tensoativos/toxicidade
6.
J Biomol Struct Dyn ; 41(1): 106-124, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-34821213

RESUMO

The RxAc drug loaded on Tween80-chitosan-TPP nanoparticles (NRxAc) has been characterized and probed by UV-Vis, PXRD, FTIR, DLS and SEM technique. The physicochemical characteristics of NRxAc have been employed and evaluated for formulation of drug, particle size, external morphology, drug content and in vitro drug release. Multi-spectroscopic (i.e. fluorescence, UV-Vis, CD spectroscopy) and molecular docking techniques were also used to study the interaction of BSA with RxAc and NRxAc. RxAc and NRxAc quenched the fluorescence emission of BSA via a static quenching mechanism. The experimental data of Fluorescence demonstrated that the binding constant of RxAc and NRxAc were found around 104 L.mol-1, which suggests moderate binding affinity with BSA via hydrophobic forces. Through the site marker displacement experiments and molecular docking, the probable binding location of RxAc and NRxAc has been suggested in subdomain IB (site III) of BSA. Altogether, the results of present study can provide an important insight and a great deal of helpful information for future design of antiulcer drugs. Hence, The RxAc-loaded chitosan nanoparticles produced might be utilized as a successful tool for developing and using antiulcer drugs.Communicated by Ramaswamy H. Sarma.


Assuntos
Quitosana , Soroalbumina Bovina , Simulação de Acoplamento Molecular , Soroalbumina Bovina/química , Quitosana/metabolismo , Sítios de Ligação , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Ligação Proteica , Termodinâmica , Dicroísmo Circular
7.
Vaccines (Basel) ; 11(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36679946

RESUMO

In spite of its high effectiveness in the treatment of both leishmaniasis as well as a range of fungal infections, the free form of the polyene antibiotic amphotericin B (AmB) does not entertain the status of the most preferred drug of choice in clinical settings. The high intrinsic toxicity of the principal drug could be considered the main impedance in the frequent medicinal use of this otherwise very effective antimicrobial agent. Taking into consideration this fact, the pharma industry has introduced many novel dosage forms of AmB to alleviate its toxicity issues. However, the limited production, high cost, requirement for a strict cold chain, and need for parenteral administration are some of the limitations that explicitly compel professionals to look for the development of an alternate dosage form of this important drug. Considering the fact that the nano-size dimensions of drug formulation play an important role in increasing the efficacy of the core drug, we employed a green method for the development of nano-assemblies of AmB (AmB-NA). The as-synthesized AmB-NA manifests desirable pharmacokinetics in the treated animals. The possible mechanistic insight suggested that as-synthesized AmB-NA induces necrosis-mediated cell death and severe mitochondrial dysfunction in L. donovani promastigotes by triggering depolarization of mitochondrial membrane potential. In vivo studies demonstrate a noticeable decline in parasite burden in the spleen, liver, and bone marrow of the experimental BALB/c mice host. In addition to successfully suppressing the Leishmania donovani, the as-formed AmB-NA formulation also modulates the host immune system with predominant Th1 polarization, a key immune defender that facilitates the killing of the intracellular parasite.

8.
Front Genet ; 13: 1022734, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36338993

RESUMO

Tumorigenesis is a multifaceted process, where multiple physiological traits serving as cancer's distinctive characteristics are acquired. "Hallmarks of cancer" is a set of cognitive abilities acquired by human cells that are pivotal to their tumor-forming potential. With limited or no protein-coding ability, non-coding RNAs (ncRNAs) interact with their target molecules and yield significant regulatory effects on several cell cycle processes. They play a "yin" and "yang" role, thereby functioning both as oncogenic and tumor suppressor and considered important in the management of various types of cancer entities. ncRNAs serve as important post-transcriptional and translational regulators of not only unrestricted expansion and metastasis of tumor cells but also of various biological processes, such as genomic mutation, DNA damage, immune escape, and metabolic disorder. Dynamical attributes such as increased proliferative signaling, migration, invasion, and epithelial-mesenchymal transition are considered to be significant determinants of tumor malignancy, metastatic dissemination, and therapeutic resistance. Furthermore, these biological attributes engage tumor cells with immune cells within the tumor microenvironment to promote tumor formation. We elaborate the interaction of ncRNAs with various factors in order to regulate cancer intra/intercellular signaling in a specific tumor microenvironment, which facilitates the cancer cells in acquiring malignant hallmarks. Exosomes represent a means of intercellular communication and participate in the maintenance of the tumor hallmarks, adding depth to the intricate, multifactorial character of malignant neoplasia. To summarize, ncRNAs have a profound impact on tumors, affecting their microcirculation, invasiveness, altered metabolism, microenvironment, and the capacity to modify the host immunological environment. Though the significance of ncRNAs in crosstalk between the tumor and its microenvironment is being extensively explored, we intend to review the hallmarks in the light of exosome-derived non-coding RNAs and their impact on the tumor microenvironment.

9.
Front Aging ; 2: 748591, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35822018

RESUMO

During the last 2 years, the entire world has been severely devastated by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic (COVID-19) as it resulted in several million deaths across the globe. While the virus infects people indiscriminately, the casualty risk is higher mainly in old, and middle-aged COVID-19 patients. The incidences of COVID-19 associated co-morbidity and mortality have a great deal of correlation with the weakened and malfunctioning immune systems of elderly people. Presumably, due to the physiological changes associated with aging and because of possible comorbidities such as diabetes, hypertension, obesity, cardiovascular, and lung diseases, which are more common in elderly people, may be considered as the reason making the elderly vulnerable to the infection on one hand, and COVID-19 associated complications on the other. The accretion of senescent immune cells not only contributes to the deterioration of host defense, but also results in elevated inflammatory phenotype persuaded immune dysfunction. In the present review, we envisage to correlate functioning of the immune defense of older COVID-19 patients with secondary/super infection, increased susceptibility or aggravation against already existing cancer, infectious, autoimmune, and other chronic inflammatory diseases. Moreover, we have discussed how age-linked modulations in the immune system affect therapeutic response against administered drugs as well as immunological response to various prophylactic measures including vaccination in the elderly host. The present review also provides an insight into the intricate pathophysiology of the aging and the overall immune response of the host to SARS-CoV-2 infection. A better understanding of age-related immune dysfunction is likely to help us in the development of targeted preemptive strategies for deadly COVID-19 in elderly patients.

10.
Front Immunol ; 12: 706727, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34777338

RESUMO

Tuberculosis (TB) is a significant and continuing problem worldwide, with a death toll of around 1.5 million human lives annually. BCG, the only vaccine against TB, offers a varied degree of protection among human subjects in different regions and races of the world. The majority of the population living near the tropics carries a varying degree of tolerance against BCG due to the widespread prevalence of non-tuberculous mycobacteria (NTM). Interestingly, ≈90% of the Mycobacterium tuberculosis (Mtb) infected population restrain the bacilli on its own, which strengthens the notion of empowering the host immune system to advance the protective efficacy of existing mycobacterial vaccines. In general, Mtb modulates IL-10/STAT3 signaling to skew host mononuclear phagocytes toward an alternatively activated, anti-inflammatory state that helps it thrive against hostile immune advances. We hypothesized that modulating the IL-10/STAT3 driven anti-inflammatory effects in mononuclear cells may improve the prophylactic ability of TB vaccines. This study investigated the immunotherapeutic ability of a porphyrin based small molecule inhibitor of IL-10/STAT3 axis, 5, 15-diphenyl porphyrin (DPP), in improving anti-TB immunity offered by second generation recombinant BCG30 (rBCG30-ARMF-II®) vaccine in mice. The DPP therapy potentiated vaccine induced anti-TB immunity by down-modulating anti-inflammatory responses, while simultaneously up-regulating pro-inflammatory immune effector responses in the immunized host. The employed DPP based immunotherapy led to the predominant activation/proliferation of pro-inflammatory monocytes/macrophages/DCs, the concerted expansion of CD4+/CD8+ effector and central memory T cells, alongside balanced Th17 and Treg cell amplification, and conferred augmented resistance to aerosol Mtb challenge in rBCG30 immunized BALB/c mice.


Assuntos
Vacina BCG/imunologia , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Mycobacterium tuberculosis/imunologia , Porfirinas/farmacologia , Tuberculose/imunologia , Animais , Vacina BCG/administração & dosagem , Plasticidade Celular/efeitos dos fármacos , Citocinas/metabolismo , Humanos , Imunização , Imunomodulação , Imunoterapia , Mediadores da Inflamação/metabolismo , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Células T de Memória/imunologia , Células T de Memória/metabolismo , Camundongos , Fagócitos/efeitos dos fármacos , Fagócitos/imunologia , Fagócitos/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Tuberculose/prevenção & controle
13.
Front Immunol ; 11: 817, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32582140

RESUMO

Visceral leishmaniasis (VL)-related mortality and morbidity imposes a great deal of health concern across the globe. The existing anti-leishmanial drug regimen generally fails to eliminate newly emerging resistant isolates of this dreadful parasite. In such circumstances, the development of a prophylactic strategy to impart protection against the disease is likely to take center stage. In order to develop a promising prophylactic vaccine, it is desirable to identify an adequately potential vaccine candidate. In silico analysis of Leishmania tubulin folding cofactor D protein predicted its potential to activate both B- and T-cell repertoires. Furthermore, the ELISA employing anti-peptide27 (a segment of tubulin folding cofactor D) antibody revealed its proficiency in VL diagnosis and treatment monitoring. The peptide27 and its cocktail with another Leishmania peptide (peptide23) prompted the up-regulation of pro-inflammatory cytokines, such as IFN-γ, TNF-α, IL-2, IL-17, etc., and the down-regulation of immune-regulatory cytokines, such as IL-10, in the immunized BALB/c mice. Coherent to the consequence of peptide-specific humoral immune response, peptide cocktail-based immunization ensued in the predominant amplification of pathogen-specific IgG2a over the IgG1 isotype, up-regulated proliferation of T lymphocytes, and enhanced production of nitric oxide, reactive oxygen species, etc. We also established that the peptide cocktail modulated host MAPK signaling to favor the amplification of Th1-dominated immune response in the host. The peptide cocktail mediated the activation of the host immune armory, which was eventually translated into a significant decline in parasitic load in the visceral organs of experimental animals challenged with Leishmania donovani.


Assuntos
Polaridade Celular/imunologia , Leishmania donovani/imunologia , Leishmaniose Visceral/imunologia , Sistema de Sinalização das MAP Quinases/imunologia , Proteínas Associadas aos Microtúbulos/imunologia , Proteínas de Protozoários/imunologia , Células Th1/imunologia , Células Th2/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Adolescente , Adulto , Animais , Modelos Animais de Doenças , Feminino , Interações Hospedeiro-Patógeno/imunologia , Humanos , Vacinas contra Leishmaniose/imunologia , Leishmaniose Visceral/sangue , Leishmaniose Visceral/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Adulto Jovem
14.
Bioinformation ; 15(11): 799-805, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31902979

RESUMO

Breast cancer is a leading cause of morbidity and mortality among women comprising about 12% females worldwide. The underlying alteration in the gene expression, molecular mechanism and metabolic pathways responsible for incidence and progression of breast tumorigenesis are yet not completely understood. In the present study, potential biomarker genes involved in the early progression for early diagnosis of breast cancer has been detailed. Regulation and Gene profiling of Ductal Carcinoma In-situ (DCIS), Invasive Ductal Carcinoma (IDC) and healthy samples have been analyzed to follow their expression pattern employing normalization, statistical calculation, DEGs annotation and Protein-Protein Interaction (PPI) network. We have performed a comparative study on differentially expressed genes among Healthy vs DCIS, Healthy vsIDC and DCIS vs IDC. We found MCM102 and SLC12A8as consistently over-expressed and LEP, SORBS1, SFRP1, PLIN1, FABP4, RBP4, CD300LG, ID4, CRYAB, ECRG4, G0S2, FMO2, ADAMTS5, CAV1, CAV2, ABCA8, MAMDC2, IGFBP6, CLDN11, TGFBR3as under-expressed genes in all the 3 conditions categorized for pre-invasive and invasive ductal breast carcinoma. These genes were further studied for the active pathways where PPAR(γ) signaling pathway was found to be significantly involved. The gene expression profile database can be a potential tool in the early diagnosis of breast cancer.

15.
Sci Rep ; 9(1): 12288, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444363

RESUMO

Nano-sized drug delivery systems (NDDS) have been widely exploited to achieve targeted delivery of pharmaco-materials. Traditional pharmaceutical approaches, implied in the synthesis of nano-formulations, are obscure owing to the incompatible physico-chemical properties of the core drug as well as some other factors crucial in development of NDDS. Infact, most of the existing methods used in development of NDDS rely on usage of additives or excipients, a special class of chemicals. Barring few exceptions, the usage of synthetic excipients ought to be curtailed because of several associated undesirable features. Such issues necessitate strategies that lead to development of the synthetic excipient free drug delivery system. Plant based extracts have great potential to induce synthesis of nano-sized particles. Considering this fact, here we propose a prototype employing orange fruit juice (OJ) to facilitate bio-mediated synthesis of nano-sized supra-molecular assemblies of 5-fluorouracil (5-FU), a potent anticancer drug. The as-synthesized 5-FU Nanoparticles (NPs) retained the anti-neoplastic efficacy of the parent compound and induced apoptosis in cancer cells. The novel 5-FU NPs formulation demonstrated enhanced efficacy against DMBA induced experimental fibrosarcoma in the mouse model when compared to the micro-sized crystals of parent 5-FU drug.


Assuntos
Citrus sinensis/química , Sistemas de Liberação de Medicamentos , Fibrossarcoma/tratamento farmacológico , Fluoruracila/síntese química , Fluoruracila/uso terapêutico , Sucos de Frutas e Vegetais , Nanopartículas/química , Neoplasias Cutâneas/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Varredura Diferencial de Calorimetria , Caspase 9/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Modelos Animais de Doenças , Progressão da Doença , Feminino , Fibrossarcoma/patologia , Fluoruracila/farmacologia , Cinética , Masculino , Camundongos Endogâmicos BALB C , Nanopartículas/ultraestrutura , Neoplasias Cutâneas/patologia , Espectroscopia de Infravermelho com Transformada de Fourier , Resultado do Tratamento , Difração de Raios X
16.
PLoS One ; 13(11): e0206459, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30395609

RESUMO

Mycobacterium tuberculosis (M.tb) contrives intracellular abode as a strategy to combat antibody onslaught. Additionally, to thrive against hostile ambiance inside host macrophages, the pathogen inhibits phago-lysosomal fusion. Finally, to further defy host cell offensives, M.tb opts for dormant phase, where it turns off or slows down most of its metabolic process as an added stratagem. While M.tb restrains most of its metabolic activities during dormancy, surprisingly latency-associated alpha-crystallin protein (Acr-1) is expressed most prominently during this phase. Interestingly, several previous studies described the potential of Acr-1 to induce the robust immuno-prophylactic response in the immunized host. It is intriguing to comprehend the apparent discrepancy that the microbe M.tb overexpresses a protein that has the potential to prime host immune system against the pathogen itself. Keeping this apparent ambiguity into consideration, it is imperative to unravel intricacies involved in the exploitation of Acr-1 by M.tb during its interaction with host immune cells. The present study suggests that Acr-1 exhibits diverse role in the maturation of macrophages (MΦs) and related immunological responses. The early encounter of bone marrow derived immune cells (pre-exposure during differentiation to MΦs) with Acr-1 (AcrMΦpre), results in hampering of their function. The pre-exposure of naïve MΦs with Acr-1 induces the expression of TIM-3 and IL-10. In contrast, exposure of fully differentiated MΦs to Acr-1 results in their down-modulation and induces the phosphorylation of STAT-1 and STAT-4 in host MΦs. Furthermore, Acr-1 mediated activation of MΦs results in the induction of Th1 and Th17 phenotype by activated T lymphocyte.


Assuntos
Proteínas de Bactérias/farmacologia , Interações Hospedeiro-Patógeno , Macrófagos/efeitos dos fármacos , Mycobacterium tuberculosis/metabolismo , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Humanos , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Mycobacterium tuberculosis/fisiologia , Fenótipo , Fosforilação/efeitos dos fármacos , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT4/metabolismo , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos
17.
Front Microbiol ; 9: 2469, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30515134

RESUMO

In the present study, we investigated potential of chitosan-based nanoparticles (CNPs) to deliver loaded therapeutic molecules to pathogen harboring macrophages. We fabricated stable CNPs employing ionic cross-linking method and evaluated their potential to target RAW 264.7 cells. The physicochemical characterization of as-synthesized CNPs was determined using electron microscopy, infrared microscopy and zeta potential measurement. Next, cellular uptake and intracellular localization studies of CNPs were followed in living RAW264.7 cells using confocal microscopy. We found that both Acr-1 loaded (CNP-A) and 4-SO4-GalNAc ligand harboring (CNP-L) chitosan nanoparticle experience increased cellular uptake by Mycobacterium smegmatis infected RAW cells. Following cellular digestion in model macrophage cell line (RAW), CNPs provide an increased immune response. Further, 4-SO4-GalNAc bearing CNP-L exhibits high binding affinity as well as antibacterial efficacy toward M. smegmatis. The data of the present study suggest that CNP-based nanoparticle offer a promising delivery strategy to target infected macrophages for prevention and eradication of intracellular pathogens such as M. smegmatis.

18.
Front Microbiol ; 9: 586, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29720966

RESUMO

Besides inciting persistent and recurrent nosocomial afflictions, Staphylococcus aureus (S. aureus), a biofilm forming pathogen, poses an increased risk of several skin as well as respiratory tract infections as well. Emerging antimicrobial resistance trend asks to search for an alternate non-antibiotic based option to combat S. aureus pathogen. In the present study, we evaluated synergistic antimicrobial potential of Zinc oxide nanorods (ZnO-NRs) and diallyl sulphide (DAS) emulsion against methicillin resistant Staphylococcus aureus (MRSA). The antimicrobial assessment study suggests that the ZnO-NR and DAS emulsion effectively suppressed both sensitive S. aureus as well as MRSA isolates. The combination treatment showed enhanced activity even at a lower concentration as compared to the single treatment based on ZnO-NRs and DAS emulsion alone. The ZnO-NRs-DAS combination showed significant inhibition of MRSA biofilm as well. The data suggest that a combination therapy, comprising of ZnO-NRs and DAS emulsion, successfully treated experimental dermatitis infection caused by MRSA in mice model.

19.
Sci Rep ; 7(1): 11873, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28928478

RESUMO

Biomimetic synthesis of nanoparticles offers a convenient and bio friendly approach to fabricate complex structures with sub-nanometer precision from simple precursor components. In the present study, we have synthesized nanoparticles of Amphotericin B (AmB), a potent antifungal agent, using Aloe vera leaf extract. The synthesis of AmB nano-assemblies (AmB-NAs) was established employing spectro-photometric and electron microscopic studies, while their crystalline nature was established by X-ray diffraction. AmB-nano-formulation showed much higher stability in both phosphate buffer saline and serum and exhibit sustained release of parent drug over an extended time period. The as-synthesized AmB-NA possessed significantly less haemolysis as well as nephrotoxicity in the host at par with Ambisome®, a liposomized AmB formulation. Interestingly, the AmB-NAs were more effective in killing various fungal pathogens including Candida spp. and evoked less drug related toxic manifestations in the host as compared to free form of the drug. The data of the present study suggest that biomimetically synthesized AmB-NA circumvent toxicity issues and offer a promising approach to eliminate systemic fungal infections in Balb/C mice.


Assuntos
Anfotericina B , Antifúngicos , Materiais Biomiméticos , Candida albicans/metabolismo , Candidíase/tratamento farmacológico , Nanopartículas , Aloe/química , Anfotericina B/química , Anfotericina B/farmacologia , Animais , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Candidíase/metabolismo , Linhagem Celular , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/uso terapêutico , Extratos Vegetais/química , Folhas de Planta/química
20.
Methods Mol Biol ; 1625: 169-211, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28584991

RESUMO

Many diseases that were considered major affliction of mankind in the past have been successfully eradicated with introduction of appropriate vaccine strategies. In order to expedite new challenges coming up to deal with various infectious diseases, nano-particulate-based subunit vaccines seem to be the demand of ordeal. The nano-vaccines can find better scope for the diseases that were not rampant in the semi-advanced world few years back. For example in present-day circumstances that corroborate with advancement in the field of medical sciences in terms of cancer chemotherapy, organ transplantation, therapy of autoimmune diseases, etc.; along with prevalence of altogether unheard diseases such as HIV infection, people are at risk of infliction with many more pathogens. In this regard, development of an effective prophylactic strategy against many opportunistic infections primarily caused by fungal pathogens needs better understanding of host pathogen relation and role of active immunity against pathogenic fungi. In the present study, we have tried to decipher effectiveness of a nano-sized vaccine delivery system in imparting protection against fungal pathogens.


Assuntos
Vacinas Fúngicas/imunologia , Fungos/imunologia , Micoses/imunologia , Nanopartículas , Animais , Anticorpos Antifúngicos/imunologia , Antígenos de Fungos/imunologia , Modelos Animais de Doenças , Feminino , Vacinas Fúngicas/administração & dosagem , Humanos , Imunização , Imunoglobulina G/imunologia , Imunoterapia , Camundongos , Micoses/diagnóstico , Micoses/prevenção & controle , Micoses/terapia
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