Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
1.
Life Sci ; 323: 121689, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37044174

RESUMO

Visceral Leishmaniasis or Kala-Azar is one of the most severe and deadly neglected tropical disease caused by the Leishmania parasite. A few number of vaccines are going through different phases in clinical trial but failing of these vaccines in successive phase trial or less efficacy, urge to develop highly immunogenic and cost-effective treatment to get rid of deadly VL. This study focuses on the development of more potent vaccine candidate against VL. The recombinant vaccine candidate LeiSp was expressed in Pichia pastoris, followed by purification and characterization. The purified protein was also tested for any post-translation modification, which favors being a potent immunogenic candidate. Further, the expression modulation of different pro-inflammatory and anti-inflammatory cytokines was evaluated in THP1 cell lines. A significant upregulation in the expression of pro-inflammatory cytokines while no significant changes were observed in the expression of anti-inflammatory cytokines. The impact of recombinant vaccine protein candidates in infected conditions were determined. Here, upon treatment with chimeric vaccine protein candidate, we observed a considerable recovery in the expression level of pro-inflammatory cytokines, which were downregulated upon infection alone. In addition to this, we found a significant decrease in the expression of anti-inflammatory cytokines, which were upregulated during infection alone. We further validated our findings in infected hPBMCs and observed similar expression modulation of pro-inflammatory and anti-inflammatory cytokines with and without treatment. Thus, the present study indicates that the chimeric LeiSp protein which was designed using bioinformatics approaches shows a potential inductive efficacy for pro-inflammatory cytokines in Leishmania-infected cells.


Assuntos
Leishmania , Vacinas contra Leishmaniose , Leishmaniose Visceral , Animais , Camundongos , Leishmaniose Visceral/prevenção & controle , Epitopos , Citocinas/metabolismo , Vacinas Sintéticas , Proteínas Recombinantes/genética , Clonagem Molecular , Camundongos Endogâmicos BALB C
2.
FASEB J ; 37(3): e22793, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36723955

RESUMO

HSP40/DNAJ family of proteins is the most diverse chaperone family, comprising about 49 isoforms in humans. Several reports have demonstrated the functional role of a few of these isoforms in the pathogenesis of various viruses, including HIV-1. Our earlier study has shown that several isoforms of HSP40 get significantly modulated at the mRNA level during HIV-1 infection in T cells. To explore the biological role of these significantly modulated isoforms, we analyzed their effect on HIV-1 gene expression and virus production using knockdown and overexpression studies. Among these isoforms, DNAJA3, DNAJB1, DNAJB7, DNAJC4, DNAJC5B, DNAJC5G, DNAJC6, DNAJC22, and DNAJC30 seem to positively regulate virus replication, whereas DNAJB3, DNAJB6, DNAJB8, and DNAJC5 negatively regulate virus replication. Further investigation on the infectivity of the progeny virion demonstrated that only DNAJB8 negatively regulates the progeny virion infectivity. It was further identified that DNAJB8 protein is involved in the downregulation of Vif protein, required for the infectivity of HIV-1 virions. DNAJB8 seems to direct Vif protein for autophagic-lysosomal degradation, leading to rescue of the cellular restriction factor APOBEC3G from Vif-mediated proteasomal degradation, resulting in enhanced packaging of APOBEC3G in budding virions and release of less infective progeny virion particles. Finally, our results also indicate that during the early stage of HIV-1 infection, enhanced expression of DNAJB8 promotes the production of less infective progeny virions, but at the later stage or at the peak of infection, reduced expression of DNJAB8 protein allows the HIV-1 to replicate and produce more infective progeny virion particles.


Assuntos
Infecções por HIV , HIV-1 , Humanos , Produtos do Gene vif do Vírus da Imunodeficiência Humana/genética , Produtos do Gene vif do Vírus da Imunodeficiência Humana/metabolismo , HIV-1/metabolismo , Proteínas Virais/metabolismo , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Produtos do Gene vif/metabolismo , Replicação Viral/fisiologia , Vírion/metabolismo , Infecções por HIV/metabolismo , Proteínas de Choque Térmico HSP40/genética , Proteínas de Choque Térmico HSP40/metabolismo , Desaminase APOBEC-3G/genética , Desaminase APOBEC-3G/metabolismo , Proteínas do Tecido Nervoso/metabolismo
3.
Biochem Biophys Res Commun ; 625: 122-127, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35961135

RESUMO

Human immunodeficiency virus-1 (HIV-1) infection leads to the development of acquired immunodeficiency syndrome (AIDS). To establish a productive infection, HIV-1 hijacks the cellular machinery and modulates various physiological processes to propagate itself. The pathways altered by HIV-1 include cell cycle, autophagy, apoptosis, cell stress pathways, immune response, antiviral response, etc. Zipper interacting protein kinase (ZIPK) is a member of the death-associated protein kinase (DAPK) family of proteins, known to be one of the key regulators of cell death and cell survival pathways. ZIPK is also involved in regulating many cellular processes that are altered during HIV-1 infection; thus, we have explored the functional role of ZIPK in HIV-1 infection. Our results show that ZIPK protein expression is downregulated during HIV-1 infection in Nef dependent manner. Overexpression of ZIPK leads to downregulation in LTR-driven gene expression and virus production, whereas ZIPK knockdown induces viral gene expression and replication. HIV-1 promoter activity is reportedly enhanced by Nef-mediated activation of some transcription factors like NFκB and STAT3. ZIPK is reported to inhibit the STAT3 activity by phosphorylating it at ser-727. Our results show that STAT3 (ser-727) phosphorylation is decreased upon overexpression of Nef with simultaneous downregulation of ZIPK expression. We finally show that HIV-1 Nef interacts with ZIPK and induces its proteasomal degradation. Overall, our data suggests that Nef is involved in downregulation of ZIPK thereby increasing the virus production through rescue of STAT3 activity.


Assuntos
Produtos do Gene nef , HIV-1 , Proteínas Quinases Associadas com Morte Celular , Produtos do Gene nef/fisiologia , HIV-1/genética , Humanos , Proteínas Quinases , Proteínas Virais , Replicação Viral , Produtos do Gene nef do Vírus da Imunodeficiência Humana/genética
5.
Cell Stress Chaperones ; 26(5): 743-768, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34318439

RESUMO

Heat shock proteins (HSPs) are a group of cellular proteins that are induced during stress conditions such as heat stress, cold shock, UV irradiation and even pathogenic insult. They are classified into families based on molecular size like HSP27, 40, 70 and 90 etc, and many of them act as cellular chaperones that regulate protein folding and determine the fate of mis-folded or unfolded proteins. Studies have also shown multiple other functions of these proteins such as in cell signalling, transcription and immune response. Deregulation of these proteins leads to devastating consequences, such as cancer, Alzheimer's disease and other life threatening diseases suggesting their potential importance in life processes. HSPs exist in multiple isoforms, and their biochemical and functional characterization still remains a subject of active investigation. In case of viral infections, several HSP isoforms have been documented to play important roles with few showing pro-viral activity whereas others seem to have an anti-viral role. Earlier studies have demonstrated that HSP40 plays a pro-viral role whereas HSP70 inhibits HIV-1 replication; however, clear isoform-specific functional roles remain to be established. A detailed functional characterization of all the HSP isoforms will uncover their role in cellular homeostasis and also may highlight some of them as potential targets for therapeutic strategies against various viral infections. In this review, we have tried to comprehend the details about cellular HSPs and their isoforms, their role in cellular physiology and their isoform-specific functions in case of virus infection with a specific focus on HIV-1 biology.


Assuntos
Infecções por HIV/metabolismo , Infecções por HIV/virologia , HIV-1/fisiologia , Proteínas de Choque Térmico/metabolismo , Família Multigênica , Proteínas de Choque Térmico/química , Humanos , Modelos Biológicos , Domínios Proteicos
6.
Cell Stress Chaperones ; 26(2): 403-416, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33405054

RESUMO

Heat shock proteins (HSPs) are a family of cellular proteins involved in a variety of biological functions including chaperone activity. HSPs are classified based on their molecular weight and each family has several isoforms in eukaryotes. HSP40 is the most diverse family acting as a co-chaperone for the highly conserved HSP70 family. Some of the isoforms are reported to be induced during heat stress. Few studies have also highlighted the diverse role of some isoforms in different stress conditions including viral infections. But till date, no study has comprehensively examined the expression profile of different HSP40 and 70 isoforms in either heat stress or HIV-1 infection, a virus that is responsible for the pandemic of AIDS. In the present study, we have compared the mRNA expression profile of HSP40 and HSP70 isoforms during heat stress and HIV-1 infection in a T-cell line and also validated the HIV-1 stress results in peripheral blood mononuclear cells. In case of HSP70, we observed that three isoforms (HSPA1A, HSPA1B, and HSPA6) are highly upregulated during heat stress, but these isoforms were found to be downregulated during the peak of HIV-1 infection. While in case of HSP40, we found that only DNAJA4, DNAJB1, and DNAJB4 showed significant upregulation during heat stress, whereas in HIV-1 infection, majority of the isoforms were induced significantly. Stress-dependent differential expression observed here indicates that different HSP40 and HSP70 isoforms may have specific roles during HIV-1 infection and thus could be important for future studies.


Assuntos
Infecções por HIV/imunologia , HIV-1/imunologia , Proteínas de Choque Térmico HSP70/imunologia , Linfócitos T/imunologia , Linhagem Celular Tumoral , Expressão Gênica , Humanos , Linfócitos T/citologia
7.
Br J Hosp Med (Lond) ; 81(5): 1-4, 2020 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-32468944

RESUMO

Following a number of epidemics in the 21st century, including Ebola and Middle East respiratory syndrome, the SARS-COV-2 virus, causing COVID-19 disease, was declared a pandemic health emergency of international concern in January 2020.


Assuntos
População Negra , Infecções por Coronavirus/etnologia , Competência Cultural , Comunicação em Saúde/métodos , Pneumonia Viral/etnologia , Betacoronavirus , COVID-19 , Comorbidade , Etnicidade , Conhecimentos, Atitudes e Prática em Saúde/etnologia , Humanos , Pandemias , Risco , Fatores de Risco , SARS-CoV-2 , Fatores Sexuais , Fatores Socioeconômicos , Reino Unido/epidemiologia
9.
J Clin Diagn Res ; 10(1): DC05-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26894064

RESUMO

INTRODUCTION: Routine phenotypic methods employing clavulanate and third generation cephalosporins to detect ESBL are not promising for isolates that co-produce an inhibitor-resistant beta lactamase like AmpC. AIM: Enhancing phenotypic detection of ESBL in AmpC co-producers by using cefepime and tazobactam. MATERIALS AND METHODS: A total of 245 isolates of Escherichia coli (123), Klebsiella spp. (87), Proteus spp.(20), Enterobacter spp. (9) and Citrobacter spp.(6) obtained over a period of 2 years from January 2013 to December 2014 from urine samples of hospitalized patients were studied. The isolates were simultaneously screened for ESBL and AmpC production. AmpC production was confirmed by modified three -dimensional test (MTDT). ESBL production was confirmed by original double disc synergy test, phenotypic disc confirmatory test (PDCT) and modified double disc synergy test (MDDST) and the results compared. RESULTS: AmpC production was confirmed in 113 (46.1%) isolates by modified three dimensional test out of 143 screened positive for AmpC. Of the 192 isolates screened positive for ESBL, ESBL production was confirmed in 162 (66.1%). DDST detected ESBLs in only134 (54.7%) while additional 28 (11.4%) ESBL positive isolates were detected by MDDST. PDCT detected total 145(59.2%) ESBL positive isolates, with cefotaxime and cefotaxime + clavulanate detecting 139 (56.7%) and ceftazidime and ceftazidime + clavulanate detecting additional 6 isolates. All the 28 (11.4%) isolates which were additionally detected ESBL producers by MDDST showed positive three dimensional test i.e. AmpC co producers. DDST detected ESBL in none of AmpC positive isolates while PDCT detected ESBL in 11 isolates showing AmpC co-production. In MDDST cefepime was the best cephalosporin in detecting ESBL in presence of AmpC production. It showed synergism with amoxicillin-clavulanate in 11(39.3%) isolates and in 24(85.7%) isolates with piperacillin-tazobactam. Third generation cephalosporins -cefotaxime, ceftazidime and cefpodoxime were not able to detect ESBL in AmpC-co producers. CONCLUSION: Modification of double disc synergy tests that combine piperacillin-tazobactum with cefepime enhances the possibility of ESBL detection.

13.
Phytochemistry ; 81: 117-25, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22784550

RESUMO

Phytochemical investigation of seed coats of Pterospermum acerifolium afforded two phytoceramides (1, 2) and two acylated phytosterol glucosides (3, 4) together with five known compounds (5-9). Their structures were elucidated on the basis of extensive spectroscopic analysis using 1D, 2D NMR and Mass spectrometry. Compounds 1, 2, 3, and 4 were assessed for their osteogenic activity using primary cultures of osteoblasts harvested from neonatal rat calvaria. Among these compounds, 1 and 2 markedly stimulated osteoblast differentiation assessed by alkaline phosphatase production and osteoblast mineralization by alizarin red-S staining.


Assuntos
Ceramidas/química , Glucosídeos/química , Malvaceae/química , Osteoblastos/efeitos dos fármacos , Fitosteróis/química , Sementes/química , Acilação , Fosfatase Alcalina/análise , Fosfatase Alcalina/química , Animais , Antraquinonas/química , Células da Medula Óssea/efeitos dos fármacos , Proteína Morfogenética Óssea 2/química , Calcificação Fisiológica , Diferenciação Celular , Ceramidas/farmacologia , Subunidade alfa 1 de Fator de Ligação ao Core/química , Hidrólise , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Osteogênese , Fitosteróis/farmacologia , Cultura Primária de Células , Ratos , Crânio/química , Crânio/efeitos dos fármacos
14.
Indian J Med Res ; 135(4): 548-54, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22664506

RESUMO

BACKGROUND & OBJECTIVES: Ocimum sanctum (OS) is known to possess various therapeutic properties. We have earlier isolated and characterized three OS compounds; Ocimarin, Ocimumoside A and Ocimumoside B. However, their role in modulating stress-induced central changes is unexplored. Thus, the present study was aimed to investigate the effect of these OS compounds on restraint stress (RS)-induced changes in the monoaminergic and antioxidant systems in the frontal cortex, striatum and hippocampus of rats. METHODS: RS was produced by immobilizing (restraining) the Sprague Dawley rats for a period of 2.5 h inside cylindrical steel tubes. The monoamine levels and the in vivo antioxidant status in brain regions were evaluated by HPLC-EC and spectrophotometric assays, respectively. RESULTS: RS significantly increased the dopamine levels in the frontal cortex and decreased in the striatum and hippocampus, and accompanied with selective increase of dopamine metabolites compared to the NS control group. The serotonin and its metabolite levels were significantly increased, while noradrenaline levels were decreased by RS in the three brain regions studied. The activities of superoxide dismutase and glutathione peroxidase in the frontal cortex and striatum were significantly increased by RS with decreased glutathione levels and increased lipid peroxidation. Pre-treatment with Ocimumoside A and B (40 mg/kg po) for a period of 3 days prevented the RS-induced changes with an efficacy similar to that of standard anti-stress (Panax quinquefolium; 100 mg/kg po) and antioxidant (Melatonin; 20 mg/kg ip) drugs, while, Ocimarin failed to modulate these changes. OS compounds per se had no effect on these parameters. INTERPRETATION & CONCLUSIONS: The present findings showed the anti-stress potential of Ocimumoside A and B in relation to their simultaneous modulatory effects on the central monoaminergic and antioxidant systems implicating their therapeutic importance in stress-related disorders. Further studies are required to understand the mechanism of action of these compounds.


Assuntos
Corpo Estriado/metabolismo , Lobo Frontal/metabolismo , Hipocampo/metabolismo , Ocimum , Extratos Vegetais/administração & dosagem , Animais , Antioxidantes/metabolismo , Corpo Estriado/efeitos dos fármacos , Dopamina/metabolismo , Lobo Frontal/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Norepinefrina/metabolismo , Ocimum/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Serotonina/metabolismo , Estresse Fisiológico/efeitos dos fármacos
15.
Phytomedicine ; 19(7): 639-47, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22455995

RESUMO

Therapies targeting central stress mechanisms are fundamental for the development of successful treatment strategies. Ocimum sanctum (OS) is an Indian medicinal plant traditionally used for the treatment of various stress-related conditions. Previously, we have isolated and characterized three OS compounds; Ocimarin, Ocimumoside A and Ocimumoside B. However, their role in modulating chronic stress-induced central changes is unexplored. Thus, in the present study the efficacy of these OS compounds have been evaluated on the chronic unpredictable stress (CUS)-induced alterations in the monoaminergic and antioxidant systems in the frontal cortex, striatum and hippocampus, along with the changes in the plasma corticosterone levels. CUS (two different types of stressors daily for seven days) resulted in a significant elevation of plasma corticosterone level, which was reversed to control levels by pretreatment with Ocimumoside A and B (40 mg/kg p.o.), while Ocimarin showed no effect. The levels of NA, DA and 5-HT were significantly decreased in all the three brain regions by CUS, with a selective increase of DA metabolites. A significant decrease in the glutathione (GSH) content, the activities of superoxide dismutase and catalase with a significant increase in the glutathione peroxidase activity and lipid peroxidation was observed in all the three regions of the brain by CUS. The OS compounds alone did not cause any significant change in the baseline values of these parameters. However, Ocimumoside A and B (40 mg/kg body p.o.) attenuated these CUS-induced alterations with an efficacy similar to that of standard anti-stress (Panax quinquefolium; 100 mg/kg p.o.) and antioxidant (Melatonin; 20 mg/kg i.p.) drugs. While, Ocimarin failed to modulate these CUS-induced alterations. Therefore, this is the first report which identified the anti-stress activity of novel Ocimumoside A and B at the level of central monoamines and antioxidant properties, implicating their therapeutic importance in the prevention of stress-related disorders.


Assuntos
Ansiolíticos/uso terapêutico , Encéfalo/efeitos dos fármacos , Cerebrosídeos/uso terapêutico , Corticosterona/sangue , Ocimum/química , Estresse Psicológico/tratamento farmacológico , Animais , Ansiolíticos/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Monoaminas Biogênicas/metabolismo , Encéfalo/metabolismo , Cerebrosídeos/farmacologia , Modelos Animais de Doenças , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/sangue , Estresse Psicológico/metabolismo
17.
Nat Prod Res ; 23(12): 1134-43, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19662579

RESUMO

Two new compounds 4-methyl-heptadec-6-enoic acid ethyl ester (2) and 3-hydroxy-2,9,11-trimethoxy-5,6-dihydro isoquino[3,2-a]isoquinolinylium (7) were isolated from an ethanolic extract of the stems of Tinospora sinensis, along with six known compounds (1, 3-6 and 8). The structures of new compounds were established on the basis of detailed spectroscopic studies. Compound 7 exhibited the highest in vitro antileishmanial activity against Leishmania donovani promastigotes and intracellular amastigotes, whereas compounds 2, 4, 5 and 6 demonstrated moderate activity. Other compounds were found to be inactive.


Assuntos
Antiprotozoários/farmacologia , Leishmania donovani/efeitos dos fármacos , Extratos Vegetais/farmacologia , Tinospora/química , Animais , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
18.
Parasitol Res ; 102(3): 561-5, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18080140

RESUMO

The chemotherapeutic interventions against visceral leishmaniasis (VL) are limited and facing serious concerns of toxicity, high cost, and emerging drug resistance. There is a greater interest in new drug developments from traditionally used medicinal plants which offers unprecedented diversity in structures and bioactivity. With this rationale, ethanolic extract of Tinospora sinensis Linn and its four fractions were tested in vitro against promastigotes and intracellular amastigotes and in vivo in Leishmania donovani infected hamsters. Ethanolic extract exhibited an appreciable activity against promastigotes (IC(50) 37.6+/-6.2 microg/ml) and intracellular amastigotes (IC(50) 29.8+/-3.4 microg/ml). In hamsters, it resulted in 76.2+/-9.2% inhibition at 500 mg/kg/day x 5 oral dose level. Among fractions, n-butanol imparted highest in vitro and in vivo activities. Ethanolic extract and butanol fraction also enhances reactive oxygen species (ROS) and nitric oxide (NO) release. The results indicate that T. sinensis may provide new lead molecules for the development of alternative drugs against VL.


Assuntos
Antiprotozoários/uso terapêutico , Leishmaniose Visceral/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Tinospora , Animais , Clorofórmio , Cricetinae , Modelos Animais de Doenças , Macrófagos/efeitos dos fármacos , Macrófagos/fisiologia , Extratos Vegetais/isolamento & purificação , Solventes
20.
Med J Armed Forces India ; 62(2): 138-40, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27407881

RESUMO

BACKGROUND: Primary giant cell tumour of soft tissues is a distinct but uncommon group of neoplasms morphologically identical to osseous giant cell tumor. METHODS: 7 patients with painless growing soft tissue mass, having no attachment to underlying bone, were identified in a four years retrospective study from two zonal hospitals of armed forces. Histopathology of these lesions revealed admixture of multinucleated giant cell with mononuclear cells. All patients were treated by surgical resection and followed up for recurrence. Results : There were 5 male and 2 female patients in the age group of 18 to 56 years. All lesions were superficial, circumscribed and involved extremities except one. Histologic transition between benign and malignant lesion was present in only one of the 7 patients that recurred after three months of surgery for which she had to be operated again. 2 of our 7 cases were lost in follow up. CONCLUSION: Primary giant cell tumour of soft tissues usually present as a painless mass and needs to be differentiated from other giant cell rich soft tissue tumors. Benign clinical course is expected if the lesion is excised adequately. Its biological behaviour to have low malignant potential is recognized; but this cannot be predicted and metastasis does occur rarely.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA