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1.
World J Microbiol Biotechnol ; 40(7): 211, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38777956

RESUMO

Human nutrition and health rely on edible oils. Global demand for edible oils is expanding, necessitating the discovery of new natural oil sources subjected to adequate quality and safety evaluation. However, in contrast to other agricultural products, India's edible oil supply is surprisingly dependent on imports. The microbial oil is generated by fermentation of oleaginous yeast Rhodotorula mucilaginosa IIPL32 MTCC 25056 using biodiesel plant byproduct crude glycerol as a fermentable carbon source. Enriched with monounsaturated fatty acid, nutritional indices mapping based on the fatty acid composition of the yeast SCO, suggested its plausible use as an edible oil blend. In the present study, acute toxicity evaluation of the yeast SCO in C57BL/6 mice has been performed by randomly dividing the animals into 5 groups with 50, 300, 2000, and 5000 mg/Kg yeast SCO dosage, respectively, and predicted the median lethal dose (LD50). Detailed blood biochemistry and kidney and liver histopathology analyses were also reported. The functions of the liver enzymes were also evaluated to check and confirm the anticipated toxicity. To determine cell viability and in vitro biocompatibility, the 3T3-L1 cell line and haemolysis tests were performed. The results suggested the plausible use of yeast SCO as an edible oil blend due to its non-toxic nature in mice models.


Assuntos
Fígado , Camundongos Endogâmicos C57BL , Rhodotorula , Animais , Camundongos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Rhodotorula/metabolismo , Fermentação , Dose Letal Mediana , Sobrevivência Celular/efeitos dos fármacos , Óleos de Plantas/toxicidade , Óleos de Plantas/metabolismo , Ácidos Graxos/metabolismo , Glicerol/metabolismo , Biocombustíveis , Rim/efeitos dos fármacos , Testes de Toxicidade Aguda , Masculino , Administração Oral , Índia
3.
Front Microbiol ; 14: 1284195, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38116526

RESUMO

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) infections are well-known hospital-borne infections and are a major contributing factor to global health concerns of antimicrobial resistance due to the formation of biofilms. Probiotics are known to assist in the healing of wounds through immunomodulation and also possess anti-pathogen properties via competitive inhibition. The probiotic bacterium, Lactiplantibacillus plantarum MTCC 2621 and its cell-free supernatant (Lp2621) have previously been reported to have antibacterial, excellent antioxidant, and wound healing activity in in vitro conditions and wounds contaminated with S. aureus in mice. Methods: In the current study, we evaluated its anti-MRSA, biofilm inhibition and eradication efficacy, immunomodulatory activity in THP-1 cells, and wound healing potential in wounds contaminated with MRSA infection in mice. Results: In agar well diffusion assay, Lp2621 showed anti-MRSA activity and revealed dose-dependent inhibition and eradication of biofilm by crystal violet assay as well as by Confocal Scanning Laser Microscopy (CLSM) analysis. Further, Lp2621 showed immunomodulatory activity at varied concentrations as measured by IL-6 and IL-10 gene expression in THP-1 cells. Similar findings were observed in serum samples of mice after treatment of excision wound contaminated with MRSA infection by Lp2621 gel, as evident by expression of IL-6 (pro-inflammatory) and IL-10 (anti-inflammatory) cytokines. Conclusions: Overall, our results show that Lp2621 has potent anti-MRSA and antioxidant properties and can prevent and eliminate biofilm formation. It also showed promise when applied to mice with MRSA-infected wounds.

4.
Front Pharmacol ; 12: 728614, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34803678

RESUMO

Lactiplantibacillus plantarum MTCC 2621 is a well-characterized probiotic strain and is reported to possess many health benefits. However, the wound healing potential of this probiotic is yet to be explored. Here, we have assessed the antibacterial, antioxidant, and wound healing activities of cell-free supernatant of Lactiplantibacillus plantarum MTCC 2621 (Lp2621). Lp2621 exhibited excellent antibacterial activity against the indicator bacteria in the agar well diffusion assay. Lp2621 did not show any hemolytic activity. The safety of Lp2621 gel was established using the skin irritation assay in BALB/c mice, and no dermal reactions were observed. The supernatant showed 60-100% protection of A549 cells against H2O2-induced stress. In the scratch assay, Lp2621 accelerated wound healing after 24 h of treatment. The percent wound healing was significantly higher in cells treated with Lp2621 at 18-24 h posttreatment. In an excision wound healing in mice, topical application of Lp2621 gel showed faster healing than the vehicle- and betadine-treated groups. Similar wound healing activity was observed in wounds infected with Staphylococcus aureus. Histological examination revealed better wound healing in Lp2621-treated mice. Topical treatment of the wounds with Lp2621 gel resulted in the upregulation of pro-inflammatory cytokine IL-6 in the early phase of wound healing and enhanced IL-10 expression in the later phase. These findings unveil a protective role of Lp2621 against bacterial infection, oxidative stress, and wound healing.

5.
PLoS Pathog ; 16(12): e1009136, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33370418

RESUMO

The level of CD40 expression on dendritic cells (DCs) plays a decisive role in disease protection during Leishmania donovani (LD) infection. However, current understanding of the molecular regulation of CD40 expression remains elusive. Using molecular, cellular and functional approaches, we identified a role for Runx1 and Runx3 transcription factors in the regulation of CD40 expression in DCs. In response to lipopolysaccharide (LPS), tumor necrosis factor alpha (TNFα) or antileishmanial drug sodium antimony gluconate (SAG), both Runx1 and Runx3 translocated to the nucleus, bound to the CD40 promoter and upregulated CD40 expression on DCs. These activities of Runx proteins were mediated by the upstream phosphatidylinositol 3-kinase (PI3K)-Akt pathway. Notably, LD infection attenuated LPS- or TNFα-induced CD40 expression in DCs by inhibiting PI3K-Akt-Runx axis via protein tyrosine phosphatase SHP-1. In contrast, CD40 expression induced by SAG was unaffected by LD infection, as SAG by blocking LD-induced SHP-1 activation potentiated PI3K-Akt signaling to drive Runx-mediated CD40 upregulation. Adoptive transfer experiments further showed that Runx1 and Runx3 play a pivotal role in eliciting antileishmanial immune response of SAG-treated DCs in vivo by promoting CD40-mediated type-1 T cell responses. Importantly, antimony-resistant LD suppressed SAG-induced CD40 upregulation on DCs by blocking the PI3K-Akt-Runx pathway through sustained SHP-1 activation. These findings unveil an immunoregulatory role for Runx proteins during LD infection.


Assuntos
Antígenos CD40/imunologia , Subunidades alfa de Fatores de Ligação ao Core/imunologia , Células Dendríticas/imunologia , Regulação da Expressão Gênica/imunologia , Leishmaniose Visceral/imunologia , Animais , Antígenos CD40/biossíntese , Cricetinae , Humanos , Leishmania donovani/imunologia , Camundongos , Camundongos Endogâmicos BALB C
6.
Sci Rep ; 10(1): 19120, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154424

RESUMO

Type-1 diabetes (T1D) is an autoimmune disease caused by progressive loss of insulin-producing beta cells in the pancreas. Butyrate is a commensal microbial-derived metabolite, implicated in intestinal homeostasis and immune regulation. Here, we investigated the mechanism of diabetes remission in non-obese diabetic (NOD) mice following butyrate administration. Sodium butyrate (150 mM) was administered to female NOD mice in drinking water after the onset of hyperglycemia (15-25 weeks age) and at 4 weeks of age (early-intervention group). Butyrate administration reduced the progression of hyperglycemia in diabetic mice and delayed onset of diabetes in the early-intervention group with a reduction in insulitis. Butyrate administration increased regulatory T cells (Tregs) in the colon, mesenteric lymph nodes, Peyer's patches, and its protective effects diminished upon depletion of Tregs. Further, an increase in α4ß7, CCR9, and GPR15 expressing Tregs in the pancreatic lymph nodes (PLN) and pancreas in butyrate-treated mice suggested migration of gut-primed Tregs towards the pancreas. Finally, the adoptive transfer experiments demonstrated that induced Tregs from gut-associated lymphoid tissue can migrate towards the pancreas and PLN and delay the onset of diabetes. Our results thus suggest that early administration of butyrate can restore immunological tolerance during T1D via induction of Tregs with migratory capabilities.


Assuntos
Ácido Butírico/farmacologia , Movimento Celular/efeitos dos fármacos , Diabetes Mellitus Tipo 1/imunologia , Tolerância Imunológica/efeitos dos fármacos , Tecido Linfoide/imunologia , Pâncreas/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Animais , Progressão da Doença , Feminino , Camundongos , Camundongos Endogâmicos NOD , Linfócitos T Reguladores/fisiologia
7.
Front Microbiol ; 11: 1167, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32595619

RESUMO

An antimicrobial substance producing strain designated as A52 was isolated from a marine sediment sample and identified as Bacillus sp., based on 16S rRNA gene sequence analysis. The ANI and dDDH analysis of the genome sequence displayed high identity with two strains of B. subtilis sub sp. subtilis. Strain A52 yielded two antimicrobial peptides (AMPs) that differed in activity spectrum. MALDI mass spectrometry analysis of HPLC purified fractions revealed mass of peptides as 3881.6 and 1061.9 Da. The antiSMASH analysis of genome sequence unraveled presence of identical biosynthetic cluster involved in production of sublancin from B. subtilis sub sp. subtilis strain 168, which yielded peptide with identical mass. The low molecular weight peptide is found to be a cyclic lipopeptide containing C16 ß-hydroxy fatty acid that resembled surfactin-like group of biosurfactants. However, it differed in fatty acid composition and antimicrobial spectrum in comparison to other surfactins produced by strains of B. subtilis. It exhibited broad spectrum antibacterial activity, inhibited growth of pathogenic strains of Candida and filamentous fungi. Further, it exhibited hemolytic activity, but did not show phytotoxic effect in seed germination experiment. The emulgel formulation of surfactin-like lipopeptide showed antimicrobial activity in vitro and did not show any irritation effects in animal studies using BALB/c mice. Moreover, surfactin-like lipopeptide displayed synergistic activity with fluconazole against Candida, indicating its potential for external therapeutic applications.

8.
Oxid Med Cell Longev ; 2020: 4045365, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104532

RESUMO

Delineation of factors which affect wound healing would be of immense value to enable on-time or early healing and reduce comorbidities associated with infections or biochemical stress like diabetes. Plasma gelsolin has been identified earlier to significantly enable injury recovery compared to placebo. This study evaluates the role of rhuGSN for its antioxidant and wound healing properties in murine fibroblasts (3T3-L1 cell line). Total antioxidant capacity of rhuGSN increased in a concentration-dependent manner (0.75-200 µg/mL). Cells pretreated with 0.375 and 0.75 µg/mL rhuGSN for 24 h exhibited a significant increase in viability in a MTT assay. Preincubation of cells with rhuGSN for 24 h followed by oxidative stress induced by exposure to H2O2 for 3 h showed cytoprotective effect. rhuGSN at 12.5 and 25 µg/mL concentration showed an enhanced cell migration after 20 h of injury in a scratch wound healing assay. The proinflammatory cytokine IL-6 levels were elevated in the culture supernatant. These results establish an effective role of rhuGSN against oxidative stress induced by H2O2 and in wound healing of 3T3-L1 fibroblast cells.


Assuntos
Antioxidantes/farmacologia , Fibroblastos/efeitos dos fármacos , Gelsolina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Células 3T3-L1 , Animais , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/metabolismo , Peróxido de Hidrogênio/toxicidade , Interleucina-6/metabolismo , Camundongos , Espécies Reativas de Oxigênio/metabolismo
9.
Front Pharmacol ; 11: 582506, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33708108

RESUMO

Pueraria tuberosa (Roxb. ex Willd.) DC. (Fabaceae), also known as Indian Kudzu (vidari kand), is a perennial herb distributed throughout India and other Asian countries. Traditionally, tuber and leaves of this plant have extensively been reported for nutritional and medicinal properties in Ayurveda as well as in Chinese traditional practices. The objective of the present review is to compile and update the published data on traditional uses, pharmacological potential, and phytochemistry of compounds isolated from the plant Pueraria tuberosa. P. tuberosa extracts and its purified compounds possess multiple activities such as anticancer, anticonvulsant, antidiabetic, antifertility, anti-inflammatory, antioxidant, anti-stress, antiulcerogenic, cardioprotective, hypolipidemic, hepatoprotective, immunomodulatory, nephroprotective, nootropic, neuroprotective, and wound healing. Tuber and leaf extracts of P. tuberosa contain several bioactive constituents such as puerarin, daidzein, genistein, quercetin, irisolidone, biochanin A, biochanin B, isoorientin, and mangiferin, which possess an extensive range of pharmacological activities. The extensive range of pharmacological properties of P. tuberosa provides opportunities for further investigation and presents a new approach for the treatment of ailments. Many phytochemicals have been identified and characterized from P. tuberosa; however, some of them are still unexplored, and there is no supporting data for their activities and exact mechanisms of action. Therefore, further investigations are warranted to unravel the mechanisms of action of individual constituents of this plant.

10.
Front Microbiol ; 10: 2153, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31620109

RESUMO

Efflux pumps are always at the forefront of bacterial multidrug resistance and account for the failure of antibiotics. The present study explored the potential of 2-(2-Aminophenyl) indole (RP2), an efflux pump inhibitor (EPI) isolated from the soil bacterium, to overcome the efflux-mediated resistance in Staphylococcus aureus. The RP2/antibiotic combination was tested against efflux pump over-expressed S. aureus strains. The compound was further examined for the ethidium bromide (EtBr) uptake and efflux inhibition assay (a hallmark of EPI functionality) and cytoplasmic membrane depolarization. The safety profile of RP2 was investigated using in vitro cytotoxicity assay and Ca2+ channel inhibitory effect. The in vivo efficacy of RP2 was studied in an animal model in combination with ciprofloxacin. RP2 exhibited the synergistic activity with several antibiotics in efflux pump over-expressed strains of S. aureus. In the mechanistic experiments, RP2 increased the accumulation of EtBr, and demonstrated the inhibition of its efflux. The antibiotic-EPI combinations resulted in extended post antibiotic effects as well as a decrease in mutation prevention concentration of antibiotics. Additionally, the in silico docking studies suggested the binding of RP2 to the active site of modeled structure of NorA efflux pump. The compound displayed low mammalian cytotoxicity and had no Ca2+ channel inhibitory effect. In ex vivo experiments, RP2 reduced the intracellular invasion of S. aureus in macrophages. Furthermore, the RP2/ciprofloxacin combination demonstrated remarkable efficacy in a murine thigh infection model. In conclusion, RP2 represents a promising candidate as bacterial EPI, which can be used in the form of a novel therapeutic regimen along with existing and upcoming antibiotics, for the eradication of S. aureus infections.

11.
Immunohorizons ; 3(8): 402-411, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31439624

RESUMO

Chronically activated CD4+ T cells drive uncontrolled inflammation, leading to tissue damage in various autoimmune disorders, such as rheumatoid arthritis (RA). Investigation of the molecular mechanisms involved in RA and recent analysis of transcriptomic profiles has implicated members of the nuclear receptor (NR) superfamily in RA. NRs are required for the development, differentiation, and effector function of CD4+ T cells; therefore, it is thought that NRs are important in shaping the CD4+ T cell repertoire and associated inflammation in RA. Despite their relevance, the full potential of the NR superfamily in RA, either as biomarkers or disease targets, has not been harnessed. To gain insight on the NR members that are closely associated with RA disease activity, we generated an expression atlas for the NR superfamily in CD4+ T cells isolated either in a steady state or over the course of collagen-induced arthritis mouse model of RA. We observed discrete expression patterns among the NR superfamily during the disease stages. NRs that instigate anti-inflammatory programs underwent major downregulation during disease onset; however, during the fully developed disease stage we noticed that NRs that induce proinflammatory programs had reduced transcript levels. These animal findings corroborated well with the expression patterns of NRs in clinical samples obtained from RA patients. Furthermore, we observed that targeting NRs using synthetic ligands alleviates the progression of collagen-induced arthritis. Overall, our data demonstrates the potential of the NR superfamily as novel therapeutic targets for the treatment of autoimmune disorders.


Assuntos
Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Anti-Inflamatórios/uso terapêutico , Anticorpos/imunologia , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/patologia , Colágeno Tipo II/imunologia , Colágeno Tipo II/farmacologia , Citocinas/metabolismo , Feminino , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos DBA , Fenilacetatos/uso terapêutico , Retinoides/uso terapêutico , Líquido Sinovial/metabolismo , Tiazóis/uso terapêutico , Tiossemicarbazonas/uso terapêutico , Transcrição Gênica
12.
Artigo em Inglês | MEDLINE | ID: mdl-30936101

RESUMO

The World Health Organization has categorized the Gram-negative superbugs, which are inherently impervious to many antibiotics, as critical priority pathogens due to the lack of effective treatments. The breach in our last-resort antibiotic (i.e., colistin) by extensively drug-resistant and pan-drug-resistant Enterobacteriaceae strains demands the immediate development of new therapies. In the present study, we report the discovery of tridecaptin M, a new addition to the family, and its potential against colistin-resistant Enterobacteriaceae in vitro and in vivo Also, we performed mode-of-action studies using various fluorescent probes and studied the hemolytic activity and mammalian cytotoxicity in two cell lines. Tridecaptin M displayed strong antibacterial activity (MICs of 2 to 8 µg ml-1) against clinical strains of Klebsiella pneumoniae (which were resistant to colistin, carbapenems, third- and fourth-generation cephalosporins, fluoroquinolones, fosfomycin, and other antibiotics) and mcr-1-positive Escherichia coli strains. Unlike polymyxins, tridecaptin M did not permeabilize the outer membrane or cytoplasmic membrane. It blocked ATP synthesis in bacteria by dissipating the proton motive force. The compound exhibited negligible acquired resistance, low in vitro cytotoxicity and hemolytic activity, and no significant acute toxicity in mice. It also showed promising efficacy in a thigh infection model of colistin-resistant K. pneumoniae Altogether, these results demonstrate the future prospects of this class of antibiotics to address the unmet medical need to circumvent colistin resistance in extensively drug-resistant Enterobacteriaceae infections. The work also emphasizes the importance of natural products in our shrunken drug discovery pipeline.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Infecções por Enterobacteriaceae/tratamento farmacológico , Enterobacteriaceae/efeitos dos fármacos , Peptídeos/farmacologia , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana
13.
PLoS One ; 14(4): e0215717, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31002695

RESUMO

The present study provides first evidence on the role of plasma gelsolin in protecting pulmonary thromboembolism and thrombosis in a mouse model. Gelsolin is the most abundant actin depolymerizing protein in plasma and its significantly depleted values have been reported in metabolic disorders including cardiovascular diseases and myocardial infarction. Though gelsolin replacement therapy (GRT) has been shown to be effective in some animal models, no such study has been reported for thrombotic diseases that are acutely in need of bio-therapeutics for immediate and lasting relief. Here, using mice model and recombinant human gelsolin (rhuGSN), we demonstrate the antithrombotic effect of gelsolin in ferric chloride induced thrombosis in carotid artery and thrombin induced acute pulmonary thromboembolism. In thrombosis model, arterial occlusion time was significantly enhanced upon subcutaneous (SC) treatment with 8 mg of gelsolin per mice viz. 15.83 minutes vs. 8 minutes in the placebo group. Pertinently, histopathological examination showed channel formation within the thrombi in the carotid artery following injection of gelsolin. Fluorescence molecular tomography imaging further confirmed that administration of gelsolin reduced thrombus formation following carotid artery injury. In thrombin-induced acute pulmonary thromboembolism, mice pretreated with aspirin or gelsolin showed 100 and 83.33% recovery, respectively. In contrast, complete mortality of mice was observed in vehicle treated group within 5 minutes of thrombin injection. Overall, our studies provide conclusive evidence on the thrombo-protective role of plasma gelsolin in mice model of pulmonary thromboembolism and thrombosis.


Assuntos
Trombose das Artérias Carótidas/prevenção & controle , Artéria Carótida Primitiva/efeitos dos fármacos , Gelsolina/farmacologia , Embolia Pulmonar/prevenção & controle , Proteínas Recombinantes/farmacologia , Trombose/prevenção & controle , Doença Aguda , Animais , Trombose das Artérias Carótidas/diagnóstico por imagem , Trombose das Artérias Carótidas/fisiopatologia , Artéria Carótida Primitiva/diagnóstico por imagem , Artéria Carótida Primitiva/fisiopatologia , Modelos Animais de Doenças , Feminino , Corantes Fluorescentes/química , Gelsolina/genética , Humanos , Camundongos Endogâmicos BALB C , Substâncias Protetoras/farmacologia , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/fisiopatologia , Trombose/diagnóstico por imagem , Trombose/fisiopatologia , Tomografia/métodos
14.
Sci Rep ; 8(1): 12602, 2018 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-30135452

RESUMO

Here, we report that minimal functional gelsolin i.e. fragment 28-161 can display F-actin depolymerizing property even after heating the protein to 80 °C. Small angle X-ray scattering (SAXS) data analysis confirmed that under Ca2+-free conditions, 28-161 associates into monomer to dimer and tetramer, which later forms ß-amyloids, but in presence of Ca2+, it forms dimers which proceed to non-characterizable aggregates. The dimeric association also explained the observed decrease in ellipticity in circular dichroism experiments with increase in temperature. Importantly, SAXS data based models correlated well with our crystal structure of dimeric state of 28-161. Characterization of higher order association by electron microscopy, Congo red and ThioflavinT staining assays further confirmed that only in absence of Ca2+ ions, heating transforms 28-161 into ß-amyloids. Gel filtration and other experiments showed that ß-amyloids keep leaching out the monomer, and the release rates could be enhanced by addition of L-Arg to the amyloids. F-actin depolymerization showed that addition of Ca2+ ions to released monomer initiated the depolymerization activity. Overall, we propose a way to compose a supramolecular assembly which releases functional protein in sustained manner which can be applied for varied potentially therapeutic interventions.


Assuntos
Actinas/metabolismo , Gelsolina/metabolismo , Citoesqueleto de Actina , Fatores de Despolimerização de Actina/metabolismo , Peptídeos beta-Amiloides/metabolismo , Cristalografia por Raios X , Gelsolina/fisiologia , Temperatura Alta , Modelos Moleculares , Ligação Proteica , Desnaturação Proteica , Temperatura , Difração de Raios X
15.
Oncogenesis ; 7(5): 43, 2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29795364

RESUMO

Early stage prostate cancers are dependent on androgens for their growth and survival and androgen withdrawal causes them to regress. Progressive prostate cancers eventually acquire androgen independence rendering anti-androgen therapy ineffective. However, the factors leading to this have not been adequately addressed. This study shows that AIRE finds differential expression in androgen-dependent and -independent prostate cancer cells. AIRE expression is more in androgen-independent cells due to its regulation by transcription factor Elk-1. These enhanced levels of AIRE modulate the prostate tumor microenvironment by transcriptionally activating a malignancy gene IL-6 in androgen-independent cells. Additionally, AIRE prevents the cancer cells from anticancer drug-induced death and enhances their invasiveness. Moreover, AIRE by modulating the cytokine milieu skews the tumor-associated macrophage polarization towards M2 phenotype with increased CD206 and CD163 expression. Subcutaneous mouse model of prostate cancer revealed AIRE+/+ mice forming a palpable tumor and presents lymphadenopathy however, only a small benign tumor is observed in AIRE-/- mice and lymph nodes appear normal in size. In conclusion, our findings suggest AIRE as a probable factor in promoting prostate cancer progression.

16.
Autophagy ; 14(6): 972-991, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29457983

RESUMO

IFNG (interferon gamma)-induced autophagy plays an important role in the elimination of intracellular pathogens, such as Mycobacterium tuberculosis (Mtb). However, the signaling cascade that leads to the increase in autophagy flux in response to IFNG is poorly defined. Here, we demonstrate that HMOX1 (heme oxygenase 1)-generated carbon monoxide (CO) is required for the induction of autophagy and killing of Mtb residing in macrophages in response to immunomodulation by IFNG. Interestingly, IFNG exposure of macrophages induces an increase in intracellular calcium levels that is dependent on HMOX1 generated CO. Chelation of intracellular calcium inhibits IFNG-mediated autophagy and mycobacterial clearance from macrophages. Moreover, we show that IFNG-mediated increase in intracellular calcium leads to activation of the phosphatase calcineurin (PPP3), which dephosphorylates the TFEB (transcription factor EB) to induce autophagy. PPP3-mediated activation and nuclear translocation of TFEB are critical in IFNG-mediated mycobacterial trafficking and survival inside the infected macrophages. These findings establish that IFNG utilizes the PPP3-TFEB signaling axis for inducing autophagy and regulating mycobacterial growth. We believe this signaling axis could act as a therapeutic target for suppression of growth of intracellular pathogens.


Assuntos
Antibacterianos/farmacologia , Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Calcineurina/metabolismo , Cálcio/metabolismo , Heme Oxigenase-1/metabolismo , Interferon gama/farmacologia , Transdução de Sinais , Animais , Sinalização do Cálcio/efeitos dos fármacos , Monóxido de Carbono/metabolismo , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Espaço Intracelular/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Mycobacterium tuberculosis/efeitos dos fármacos , Biogênese de Organelas , Transporte Proteico/efeitos dos fármacos , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Tuberculose/microbiologia , Tuberculose/patologia
17.
Am J Physiol Regul Integr Comp Physiol ; 314(4): R509-R522, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29341830

RESUMO

Plasma gelsolin (pGSN), a protein primarily involved in clearance of circulating actin filaments, is an upcoming novel biomarker. Its level changes in multiple disease and injury conditions, attributable mainly to its consumption during actin clearance; the endogenous regulation of its expression, however, remains elusive as well as unexplored. Here, we are reporting the first isolation of the promoter region of pGSN gene and investigation of its transcriptional regulation during pregnancy (a natural process associated with a well-programmed injury course of parturition). Interestingly, two of the pregnancy-related hormones, human chorionic gonadotrophin (hCG) and progesterone, significantly upregulated pGSN promoter activity in muscle cells. This action of both hormones was found to mediate through their respective cellular receptors and involved a contribution of multiple signaling pathways including those of protein kinase A, protein kinase C, epidermal growth factor receptor and prostaglandin-endoperoxidase synthase 2 in the case of hCG-mediated upregulation. This novel upregulation was further supported by elevated levels of endogenous pGSN transcripts as well as secreted protein upon hormonal treatments of muscle cells compared with untreated controls. A participation of pGSN promoter cis-elements, capable of interacting with endogenous transcription factors, Ap1, Sp1, and p300, was also observed during this hormonal upregulation. Additionally, the augmented pGSN levels observed in pregnant mice compared with the control animals further supported an upregulation of this protein during pregnancy, implicating vital role(s) played by pGSN during this period in mammals.


Assuntos
Gonadotropina Coriônica/farmacologia , Gelsolina/sangue , Miócitos de Músculo Liso/efeitos dos fármacos , Progesterona/farmacologia , Animais , Proteína p300 Associada a E1A/genética , Proteína p300 Associada a E1A/metabolismo , Feminino , Gelsolina/genética , Células HeLa , Humanos , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/metabolismo , Gravidez , Regiões Promotoras Genéticas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Regulação para Cima
18.
J Immunol ; 197(5): 1650-62, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27439518

RESUMO

The enhanced expression of T cell Ig and mucin protein-3 (TIM-3) on tumor-associated dendritic cells (DCs) attenuates antitumor effects of DNA vaccines. To identify a potential target (or targets) for reducing TIM-3 expression on tumor-associated DCs, we explored the molecular mechanisms regulating TIM-3 expression. In this study, we have identified a novel signaling pathway (c-Src→Bruton's tyrosine kinase→transcription factors Ets1, Ets2, USF1, and USF2) necessary for TIM-3 upregulation on DCs. Both IL-10 and TGF-ß, which are produced in the tumor microenvironment, upregulated TIM-3 expression on DCs via this pathway. Suppressed expression of c-Src or downstream Bruton's tyrosine kinase, Ets1, Ets2, USF1, or USF2 blocked IL-10- and TGF-ß-induced TIM-3 upregulation on DCs. Notably, in vivo knockdown of c-Src in mice reduced TIM-3 expression on tumor-associated DCs. Furthermore, adoptive transfer of c-Src-silenced DCs in mouse tumors enhanced the in vivo antitumor effects of immunostimulatory CpG DNA; however, TIM-3 overexpression in c-Src-silenced DCs blocked this effect. Collectively, our data reveal the molecular mechanism regulating TIM-3 expression in DCs and identify c-Src as a target for improving the efficacy of nucleic acid-mediated anticancer therapy.


Assuntos
Células Dendríticas/imunologia , Genes src , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Neoplasias/imunologia , Linfócitos T/imunologia , Quinases da Família src/metabolismo , Transferência Adotiva , Tirosina Quinase da Agamaglobulinemia , Animais , Proteína Tirosina Quinase CSK , Diferenciação Celular , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Receptor Celular 2 do Vírus da Hepatite A/genética , Interleucina-10/imunologia , Interleucina-10/metabolismo , Camundongos , Neoplasias/metabolismo , Oligodesoxirribonucleotídeos/imunologia , Proteínas Tirosina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/imunologia , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima
19.
Sci Rep ; 6: 26278, 2016 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-27189051

RESUMO

Skin, being the largest organ of the body, is an important site for drug administration. However, most of the drugs have poor permeability and thus drug delivery through the skin is very challenging. In this study, we examined the transdermal delivery capability of IMT-P8, a novel cell-penetrating peptide. We generated IMT-P8-GFP and IMT-P8-KLA fusion constructs and evaluated their internalization into mouse skin after topical application. Our results demonstrate that IMT-P8 is capable of transporting green fluorescent protein (GFP) and proapoptotic peptide, KLA into the skin and also in different cell lines. Interestingly, uptake of IMT-P8-GFP was considerably higher than TAT-GFP in HeLa cells. After internalization, IMT-P8-KLA got localized to the mitochondria and caused significant cell death in HeLa cells signifying an intact biological activity. Further in vivo skin penetration experiments revealed that after topical application, IMT-P8 penetrated the stratum corneum, entered into the viable epidermis and accumulated inside the hair follicles. In addition, both IMT-P8-KLA and IMT-P8-GFP internalized into the hair follicles and dermal tissue of the skin following topical application. These results suggested that IMT-P8 could be a potential candidate to be used as a topical delivery vehicle for various cosmetic and skin disease applications.


Assuntos
Peptídeos Penetradores de Células/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Administração Tópica , Animais , Transporte Biológico , Morte Celular , Linhagem Celular Tumoral , Peptídeos Penetradores de Células/administração & dosagem , Peptídeos Penetradores de Células/genética , Sistemas de Liberação de Medicamentos , Epiderme/metabolismo , Proteínas de Fluorescência Verde/genética , Folículo Piloso/metabolismo , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Masculino , Camundongos Endogâmicos BALB C , Mitocôndrias/metabolismo , Peptídeos/genética , Permeabilidade , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética
20.
Antimicrob Agents Chemother ; 60(1): 580-91, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-26574006

RESUMO

Attempts to isolate novel antimicrobial peptides from microbial sources have been on the rise recently, despite their low efficacy in therapeutic applications. Here, we report identification and characterization of a new efficient antimicrobial peptide from a bacterial strain designated A3 that exhibited highest identity with Paenibacillus ehimensis. Upon purification and subsequent molecular characterization of the antimicrobial peptide, referred to as penisin, we found the peptide to be a bacteriocin-like peptide. Consistent with these results, RAST analysis of the entire genome sequence revealed the presence of a lantibiotic gene cluster containing genes necessary for synthesis and maturation of a lantibiotic. While circular dichroism and one-dimension nuclear magnetic resonance experiments confirmed a random coil structure of the peptide, similar to other known lantibiotics, additional biochemical evidence suggests posttranslational modifications of the core peptide yield six thioether cross-links. The deduced amino acid sequence of the putative biosynthetic gene penA showed approximately 74% similarity with elgicin A and 50% similarity with the lantibiotic paenicidin A. Penisin effectively killed methicillin-resistant Staphylococcus aureus (MRSA) and did not exhibit hemolysis activity. Unlike other lantibiotics, it effectively inhibited the growth of Gram-negative bacteria. Furthermore, 80 mg/kg of body weight of penisin significantly reduced bacterial burden in a mouse thigh infection model and protected BALB/c mice in a bacteremia model entailing infection with Staphylococcus aureus MTCC 96, suggesting that it could be a promising new antimicrobial peptide.


Assuntos
Antibacterianos/química , Bacteriocinas/química , Genoma Bacteriano , Paenibacillus/genética , Processamento de Proteína Pós-Traducional , Infecções Estafilocócicas/tratamento farmacológico , Sequência de Aminoácidos , Animais , Antibacterianos/biossíntese , Antibacterianos/farmacologia , Bacteriocinas/biossíntese , Bacteriocinas/genética , Bacteriocinas/farmacologia , Expressão Gênica , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Família Multigênica , Paenibacillus/química , Paenibacillus/metabolismo , Estrutura Secundária de Proteína , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/mortalidade , Infecções Estafilocócicas/patologia , Análise de Sobrevida , Resultado do Tratamento
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