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1.
Cell ; 164(5): 840-2, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26919422

RESUMO

TGF-ß is long considered a "protean" cytokine in cancer, changing its role from anti- to pro-tumorigenic in a context-dependent manner. In this issue of Cell, David et al. use mouse models of pancreatic cancer to shed light on the mechanistic basis of how TGF-ß-induced EMT is coupled to either apoptosis or tumor progression.


Assuntos
Carcinoma Ductal/genética , Transição Epitelial-Mesenquimal , Redes Reguladoras de Genes , Neoplasias Pancreáticas/genética , Fator de Crescimento Transformador beta/antagonistas & inibidores , Animais
2.
New Phytol ; 238(3): 1263-1277, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36721257

RESUMO

The adaptation of weeds to herbicide is both a significant problem in agriculture and a model of rapid adaptation. However, significant gaps remain in our knowledge of resistance controlled by many loci and the evolutionary factors that influence the maintenance of resistance. Here, using herbicide-resistant populations of the common morning glory (Ipomoea purpurea), we perform a multilevel analysis of the genome and transcriptome to uncover putative loci involved in nontarget-site herbicide resistance (NTSR) and to examine evolutionary forces underlying the maintenance of resistance in natural populations. We found loci involved in herbicide detoxification and stress sensing to be under selection and confirmed that detoxification is responsible for glyphosate (RoundUp) resistance using a functional assay. We identified interchromosomal linkage disequilibrium (ILD) among loci under selection reflecting either historical processes or additive effects leading to the resistance phenotype. We further identified potential fitness cost loci that were strongly linked to resistance alleles, indicating the role of genetic hitchhiking in maintaining the cost. Overall, our work suggests that NTSR glyphosate resistance in I. purpurea is conferred by multiple genes which are potentially maintained through generations via ILD, and that the fitness cost associated with resistance in this species is likely a by-product of genetic hitchhiking.


Assuntos
Herbicidas , Ipomoea , Resistência a Herbicidas/genética , Desequilíbrio de Ligação/genética , Evolução Biológica , Herbicidas/farmacologia , Ipomoea/genética
3.
Rheumatol Int ; 41(2): 275-284, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33423070

RESUMO

The aims of this systematic review and meta-analysis were to: (1) describe the prevalence of commonly reported comorbidities in psoriatic arthritis (PsA), (2) compare the incidence and/or prevalence of comorbidities between PsA and control populations; and (3) examine the impact of comorbidities on PsA outcomes. We systematically searched Medline, PubMed, Scopus, and Web of Science using a predefined protocol in accordance with PRISMA guidelines. Studies reporting only one comorbidity, or a few closely related diseases within one organ system, were excluded. Where possible, meta-analysis was performed using random-effects models. We included 39 studies amounting to over 152 thousand PsA patients. We performed meta-analysis for the prevalence of 21 commonly reported comorbidities. The most prevalent comorbidities were hypertension (pooled prevalence 34%), metabolic syndrome (29%), obesity (27%), hyperlipidaemia (24%) and any cardiovascular diseases (19%). Eleven studies consistently showed higher prevalence of comorbidities in PsA than controls. Five studies showed that comorbid patients had more severe disease, poorer quality of life, and increased discontinuation of treatment. Comorbidities, particularly cardiometabolic disorders, were highly prevalent in PsA and more common than in healthy controls. Comorbidities were associated with adverse disease features, but more research is needed on their impact on longitudinal outcomes such as treatment response, work productivity and mortality.


Assuntos
Artrite Psoriásica/epidemiologia , Qualidade de Vida , Doenças Cardiovasculares/epidemiologia , Doença Crônica/epidemiologia , Comorbidade , Depressão/epidemiologia , Feminino , Humanos , Masculino , Síndrome Metabólica/epidemiologia , Prevalência
4.
Rheumatol Int ; 41(7): 1209-1219, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33987709

RESUMO

The aims of this systematic review and meta-analysis were to describe prevalence of cardiovascular disease in gout, compare these results with non-gout controls and consider whether there were differences according to geography. PubMed, Scopus and Web of Science were systematically searched for studies reporting prevalence of any cardiovascular disease in a gout population. Studies with non-representative sampling, where a cohort had been used in another study, small sample size (< 100) and where gout could not be distinguished from other rheumatic conditions were excluded, as were reviews, editorials and comments. Where possible meta-analysis was performed using random-effect models. Twenty-six studies comprising 949,773 gout patients were included in the review. Pooled prevalence estimates were calculated for five cardiovascular diseases: myocardial infarction (2.8%; 95% confidence interval (CI)s 1.6, 5.0), heart failure (8.7%; 95% CI 2.9, 23.8), venous thromboembolism (2.1%; 95% CI 1.2, 3.4), cerebrovascular accident (4.3%; 95% CI 1.8, 9.7) and hypertension (63.9%; 95% CI 24.5, 90.6). Sixteen studies reported comparisons with non-gout controls, illustrating an increased risk in the gout group across all cardiovascular diseases. There were no identifiable reliable patterns when analysing the results by country. Cardiovascular diseases are more prevalent in patients with gout and should prompt vigilance from clinicians to the need to assess and stratify cardiovascular risk. Future research is needed to investigate the link between gout, hyperuricaemia and increased cardiovascular risk and also to establish a more thorough picture of prevalence for less common cardiovascular diseases.


Assuntos
Doenças Cardiovasculares/epidemiologia , Gota/epidemiologia , Comorbidade , Humanos , Incidência , Prevalência
5.
Genome Res ; 27(11): 1830-1842, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28986391

RESUMO

Transcriptional deregulation of oncogenic pathways is a hallmark of cancer and can be due to epigenetic alterations. 5-Hydroxymethylcytosine (5-hmC) is an epigenetic modification that has not been studied in pancreatic cancer. Genome-wide analysis of 5-hmC-enriched loci with hmC-seal was conducted in a cohort of low-passage pancreatic cancer cell lines, primary patient-derived xenografts, and pancreatic controls and revealed strikingly altered patterns in neoplastic tissues. Differentially hydroxymethylated regions preferentially affected known regulatory regions of the genome, specifically overlapping with known H3K4me1 enhancers. Furthermore, base pair resolution analysis of cytosine methylation and hydroxymethylation with oxidative bisulfite sequencing was conducted and correlated with chromatin accessibility by ATAC-seq and gene expression by RNA-seq in pancreatic cancer and control samples. 5-hmC was specifically enriched at open regions of chromatin, and gain of 5-hmC was correlated with up-regulation of the cognate transcripts, including many oncogenic pathways implicated in pancreatic neoplasia, such as MYC, KRAS, VEGFA, and BRD4 Specifically, BRD4 was overexpressed and acquired 5-hmC at enhancer regions in the majority of neoplastic samples. Functionally, acquisition of 5-hmC at BRD4 promoter was associated with increase in transcript expression in reporter assays and primary samples. Furthermore, blockade of BRD4 inhibited pancreatic cancer growth in vivo. In summary, redistribution of 5-hmC and preferential enrichment at oncogenic enhancers is a novel regulatory mechanism in human pancreatic cancer.


Assuntos
5-Metilcitosina/análogos & derivados , Neoplasias Pancreáticas/genética , Sequências Reguladoras de Ácido Nucleico , Análise de Sequência de RNA/métodos , 5-Metilcitosina/metabolismo , Animais , Linhagem Celular Tumoral , Epigênese Genética , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla , Histonas/metabolismo , Humanos , Camundongos , Transplante de Neoplasias , Modelagem Computacional Específica para o Paciente
6.
New Phytol ; 225(5): 2183-2195, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31652341

RESUMO

Leaf shape, a spectacularly diverse plant trait, varies across taxonomic levels, geography and in response to environmental differences. However, comprehensive intraspecific analyses of leaf shape variation across variable environments is surprisingly absent. Here, we performed a multilevel analysis of leaf shape using diverse accessions of sweet potato (Ipomoea batatas), and uncovered the role of genetics, environment, and G×E on this important trait. We examined leaf shape using a variety of morphometric analyses, and complement this with a transcriptomic survey to identify gene expression changes associated with shape variation. Additionally, we examined the role of genetics and environment on leaf shape by performing field studies in two geographically separate common gardens. We showed that extensive leaf shape variation exists within I. batatas, and identified promising candidate genes associated with this variation. Interestingly, when considering traditional measures, we found that genetic factors are largely responsible for most of leaf shape variation, but that the environment is highly influential when using more quantitative measures via leaf outlines. This extensive and multilevel examination of leaf shape shows an important role of genetics underlying a potentially important agronomic trait, and highlights that the environment can be a strong influence when using more quantitative measures of leaf shape.


Assuntos
Ipomoea batatas , Folhas de Planta/anatomia & histologia , Meio Ambiente , Interação Gene-Ambiente , Ipomoea batatas/genética
7.
Rheumatology (Oxford) ; 59(9): 2199-2206, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32160297

RESUMO

OBJECTIVE: To describe the prevalence of extra-articular manifestations-enthesitis, dactylitis, nail disease, uveitis and IBD-in PsA, and their impact on longitudinal disease outcomes. METHODS: We searched Medline, PubMed, Scopus and Web of Science using a predefined protocol in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies using imaging to define extra-articular manifestations (EAMs) were excluded. Where possible, we performed meta-analyses of prevalence estimates, reported as percentages (95% CI). Heterogeneity (I2 statistic) was examined according to study characteristics. RESULTS: We identified 65 studies amounting to a total of 163 299 PsA patients. Enthesitis was assessed in 29 studies with an average prevalence of 30% (95% CI: 24%, 38%). Dactylitis was reported in 35 studies with an average prevalence of 25% (95% CI: 20%, 31%). Nail disease was present in 60% (95% CI: 52%, 68%) across 26 studies, but definitions were often unclear. Uveitis (3.2%; 95% CI: 1.9%, 5.3%) and IBD (3.3%; 95% CI: 1.5%, 7.1%) were less common. Heterogeneity was high (>95%) in all meta-analyses, but could not be explained by study characteristics. No studies examined the impact of EAMs on longitudinal disease outcomes, except that dactylitis increases radiographic progression. CONCLUSION: Enthesitis, dactylitis and nail disease are highly prevalent in PsA, but not uveitis and IBD. EAM patterns differ from axial SpA despite their shared disease mechanisms, which may help further understand differences between spondyloarthritides. More studies are needed on the impact of EAMs on disease outcomes such as response to treatment.


Assuntos
Artrite Psoriásica/complicações , Doenças Ósseas/epidemiologia , Entesopatia/epidemiologia , Doenças Inflamatórias Intestinais/epidemiologia , Doenças da Unha/epidemiologia , Uveíte/epidemiologia , Adulto , Idoso , Doenças Ósseas/etiologia , Entesopatia/etiologia , Feminino , Dedos/patologia , Humanos , Doenças Inflamatórias Intestinais/etiologia , Masculino , Pessoa de Meia-Idade , Doenças da Unha/etiologia , Prevalência , Uveíte/etiologia
8.
Malar J ; 19(1): 122, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32209094

RESUMO

Please note, following publication of the original article [1], the authors have advised of two errors that are present in the published article.

9.
Rheumatol Int ; 40(8): 1215-1221, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32494889

RESUMO

OBJECTIVE: To describe the prevalence of depression among patients with primary systemic vasculitides (PSV); compare prevalence according to vasculitis type and against controls; and examine the impact of depression on PSV outcomes. METHODS: We searched Medline, PubMed, Scopus and Web of Science using a predefined protocol in accordance with PRISMA guidelines. We included all studies that reported the prevalence or impact of depression in PSV. We also included polymyalgia rheumatica (PMR) given its association with giant cell arteritis (GCA). Meta-analyses of prevalence estimates were performed using random-effects models and reported as percentages (95% confidence interval). RESULTS: We reviewed a total of 15 studies that described the prevalence of depression, categorised into small (n = 10) and large vessel vasculitis (n = 7). Pooled prevalence estimate for depression in a small vessel (predominantly ANCA-associated) vasculitis was 28% (95% CI 20-38%) with significant heterogeneity (I2 = 93%). Depression prevalence in large-vessel vasculitis (Takayasu and GCA/PMR) was 24% (95% CI 17-34%), again with significant heterogeneity (I2 = 96%). One study reported 56% prevalence of depression in medium vessel disease. The prevalence of depression in small vessel vasculitis was higher than healthy controls. In these patients, depression and depressive symptoms were associated with poorer quality of life, adherence, and work disability, but not disease activity or damage. CONCLUSION: Depression is highly prevalent among patients with primary systemic vasculitis and associated with poorer outcomes across a range of measures in studies of small vessel disease. Further studies are needed for depression in medium and large vessel vasculitides.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/psicologia , Depressão/epidemiologia , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Estudos de Casos e Controles , Depressão/etiologia , Arterite de Células Gigantes/complicações , Arterite de Células Gigantes/psicologia , Humanos , Polimialgia Reumática/complicações , Polimialgia Reumática/psicologia , Qualidade de Vida
10.
Lab Invest ; 99(8): 1233-1244, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30728464

RESUMO

Genetically engineered mouse models (GEMMs) that recapitulate the major genetic drivers in pancreatic ductal adenocarcinoma (PDAC) have provided unprecedented insights into the pathogenesis of this lethal neoplasm. Nonetheless, generating an autochthonous model is an expensive, time consuming and labor intensive process, particularly when tissue specific expression or deletion of compound alleles are involved. In addition, many of the current PDAC GEMMs cause embryonic, pancreas-wide activation or loss of driver alleles, neither of which reflects the cognate human disease scenario. The advent of CRISPR/Cas9 based gene editing can potentially circumvent many of the aforementioned shortcomings of conventional breeding schema, but ensuring the efficiency of gene editing in vivo remains a challenge. Here we have developed a pipeline for generating PDAC GEMMs of complex genotypes with high efficiency using a single "workhorse" mouse strain expressing Cas9 in the adult pancreas under a p48 promoter. Using adeno-associated virus (AAV) mediated delivery of multiplexed guide RNAs (sgRNAs) to the adult murine pancreas of p48-Cre; LSL-Cas9 mice, we confirm our ability to express an oncogenic Kras G12D allele through homology-directed repair (HDR), in conjunction with CRISPR-induced disruption of cooperating alleles (Trp53, Lkb1 and Arid1A). The resulting GEMMs demonstrate a spectrum of precursor lesions (pancreatic intraepithelial neoplasia [PanIN] or Intraductal papillary mucinous neoplasm [IPMN] with eventual progression to PDAC. Next generation sequencing of the resulting murine PDAC confirms HDR of oncogenic KrasG12D allele at the endogenous locus, and insertion deletion ("indel") and frameshift mutations of targeted tumor suppressor alleles. By using a single "workhorse" mouse strain and optimal AAV serotype for in vivo gene editing with combination of driver alleles, we present a facile autochthonous platform for interrogation of the PDAC genome.


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Neoplasias Experimentais , Neoplasias Pancreáticas , Recombinação Genética/genética , Animais , Dependovirus/genética , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , RNA Guia de Cinetoplastídeos/genética
11.
Gastroenterology ; 155(5): 1593-1607.e12, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30142336

RESUMO

BACKGROUND & AIMS: Mutations at hotspots in GNAS, which encodes stimulatory G-protein, α subunits, are detected in approximately 60% of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas. We generated mice with KRAS-induced IPMNs that also express a constitutively active form of GNAS in pancreas and studied tumor development. METHODS: We generated p48-Cre; LSL-KrasG12D; Rosa26R-LSL-rtTA-TetO-GnasR201C mice (Kras;Gnas mice); pancreatic tissues of these mice express activated KRAS and also express a mutant form of GNAS (GNASR201C) upon doxycycline administration. Mice that were not given doxycycline were used as controls, and survival times were compared by Kaplan-Meier analysis. Pancreata were collected at different time points after doxycycline administration and analyzed by histology. Pancreatic ductal adenocarcinomas (PDACs) were isolated from mice and used to generate cell lines, which were analyzed by reverse transcription polymerase chain reaction, immunoblotting, immunohistochemistry, and colony formation and invasion assays. Full-length and mutant forms of yes-associated protein (YAP) were expressed in PDAC cells. IPMN specimens were obtained from 13 patients with IPMN undergoing surgery and analyzed by immunohistochemistry. RESULTS: All Kras;Gnas mice developed pancreatic cystic lesions that resemble human IPMNs; the grade of epithelial dysplasia increased with time. None of the control mice developed cystic lesions. Approximately one third of Kras;Gnas mice developed PDACs at a median of 30 weeks after doxycycline administration, whereas 33% of control mice developed PDACs. Expression of GNASR201C did not accelerate the development of PDACs compared with control mice. However, the neoplasms observed in Kras;Gnas mice were more differentiated, and expressed more genes associated with ductal phenotypes, than in control mice. PDACs isolated from Kras;Gnas mice had activation of the Hippo pathway; in cells from these tumors, phosphorylated YAP1 was sequestered in the cytoplasm, and this was also observed in human IPMNs with GNAS mutations. Sequestration of YAP1 was not observed in PDAC cells from control mice. CONCLUSIONS: In mice that express activated KRAS in the pancreas, we found expression of GNASR201C to cause development of more differentiated tumors, with gene expression pattern associated with the ductal phenotype. Expression of mutant GNAS caused phosphorylated YAP1 to be sequestered in the cytoplasm, altering tumor progression.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Carcinoma Ductal Pancreático/etiologia , Cromograninas/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Mutação , Neoplasias Císticas, Mucinosas e Serosas/etiologia , Neoplasias Pancreáticas/etiologia , Fosfoproteínas/fisiologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/análise , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Animais , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Cromograninas/fisiologia , Subunidades alfa Gs de Proteínas de Ligação ao GTP/fisiologia , Humanos , Camundongos , Fosfoproteínas/análise , Fosfoproteínas/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/fisiologia , Proteínas de Sinalização YAP
12.
Gastroenterology ; 155(1): 210-223.e3, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29604293

RESUMO

BACKGROUND & AIMS: Little is known about how the immune system affects stem cell features of pancreatic cancer cells. Immune cells that produce interleukin 17A (IL17A) in the chronically inflamed pancreas (chronic pancreatitis) contribute to pancreatic interepithelial neoplasia (PanIN) initiation and progression. We investigated the effects that IL17A signaling exerts on pancreatic cancer progenitor cells and the clinical relevance of this phenomena. METHODS: We performed studies with Mist1Cre;LSLKras;Rosa26mTmG (KCiMist;G) and Kras(G12D);Trp53(R172H);Pdx1-Cre (KPC) mice (which upon tamoxifen induction spontaneously develop PanINs) and control littermates. Some mice were injected with neutralizing antibodies against IL17A or control antibody. Pancreata were collected, PanIN epithelial cells were isolated by flow cytometry based on lineage tracing, and gene expression profiles were compared. We collected cells from pancreatic tumors of KPC mice, incubated them with IL17 or control media, measured expression of genes regulated by IL17 signaling, injected the cancer cells into immune competent mice, and measured tumor growth. IL17A was overexpressed in pancreata of KCiMist mice from an adenoviral vector. Pancreata were collected from all mice and analyzed by histology and immunohistochemistry. Levels of DCLK1 and other proteins were knocked down in KPC pancreatic cancer cells using small interfering or short hairpin RNAs; cells were analyzed by immunoblotting. We obtained 65 pancreatic tumor specimens from patients, analyzed protein levels by immunohistochemistry, and compared results with patient survival times. We also analyzed gene expression levels and patient outcome using The Cancer Genome Atlas database. RESULTS: PanIN cells from KCiMist;G mice had a gene expression pattern associated with embryonic stem cells. Mice given injections of IL17-neutralizing antibodies, or with immune cells that did not secrete IL17, lost this expression pattern and had significantly decreased expression of DCLK1 and POU2F3, which regulate tuft cell development. KCiMist mice that overexpressed IL17 formed more PanINs, with more DCLK1-positive cells, than control mice. Pancreatic tumor cells from KPC mice and human Capan-2 cells exposed to IL17A had increased activation of NF-κB and mitogen-activated protein kinase signaling and increased expression of DCLK1 and ALDH1A1 (a marker of embryonic stem cells) compared with cells in control media. These cells also formed tumors faster that cells not exposed to IL17 when they were injected into immunocompetent mice. KPC cells with knockdown of DCLK1 expressed lower levels of ALDH1A1 after incubation with IL17 than cells without knockdown. Expression of the IL17 receptor C was higher in DCLK1-positive PanIN cells from mice compared with DCLK1-negative PanIN cells. In human pancreatic tumor tissues, high levels of DCLK1 associated with a shorter median survival time of patients (17.7 months, compared with 26.6 months of patients whose tumors had low levels of DCLK1). Tumor levels of POU2F3 and LAMC2 were also associated with patient survival time. CONCLUSIONS: In studies of mouse and human pancreatic tumors and precursors, we found that immune cell-derived IL17 regulated development of tuft cells and stem cell features of pancreatic cancer cells via increased expression of DCLK1, POU2F3, ALDH1A1, and IL17RC. Strategies to disrupt this pathway might be developed to prevent pancreatic tumor growth and progression.


Assuntos
Adenocarcinoma in Situ/imunologia , Carcinoma Ductal Pancreático/imunologia , Interleucina-17/imunologia , Células-Tronco Neoplásicas/imunologia , Neoplasias Pancreáticas/imunologia , Adenocarcinoma in Situ/genética , Aldeído Desidrogenase/genética , Família Aldeído Desidrogenase 1 , Animais , Anticorpos Neutralizantes/farmacologia , Carcinoma Ductal Pancreático/genética , Bases de Dados Factuais , Progressão da Doença , Quinases Semelhantes a Duplacortina , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Humanos , Interleucina-17/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Fatores de Transcrição de Octâmero/genética , Neoplasias Pancreáticas/genética , Pancreatite Crônica/genética , Pancreatite Crônica/imunologia , Proteínas Serina-Treonina Quinases/genética , Receptores de Interleucina/genética , Retinal Desidrogenase
13.
Med Microbiol Immunol ; 208(2): 185-195, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30671633

RESUMO

Bacillus anthracis (BA), the etiological agent of anthrax, secretes protective antigen (PA), lethal factor (LF), and edema factor (EF) as major virulence mediators. Amongst these, PA-based vaccines are most effective for providing immunity against BA, but their low shelf life limits their usage. Previous studies showed that B-cell epitopes, ID II and ID III present in PA domain IV possess higher toxin neutralization activity and elicit higher antibody titer than ID I. Moreover, N-terminal region of both LF and EF harbors PA-binding sites which share 100% identity with each other. Here, in this study, we have developed an epitope-based chimeric vaccine (ID-LFn) comprising ID II-ID III region of PA and N-terminal region of LF. We have also evaluated its protective efficacy as well as stability and found it to be more stable than PA-based vaccine. Binding reactivities of ID-LFn with anti-PA/LF/EF antibodies were determined by ELISA. The stability of chimeric vaccine was assessed using circular dichroism spectroscopy. ID-LFn response was characterized by toxin neutralization, lymphocyte proliferation isotyping and cytokine profiling. The protective efficacy was analyzed by challenging ID-LFn-immunized mice with B. anthracis (pXO1+ and pXO2+). ID-LFn was found to be significantly stable as compared to PA. Anti-ID-LFn antibodies recognized PA, LF as well as EF. The T-cell response and the protective efficacy of ID-LFn were found to be almost similar to PA. ID-LFn exhibits equal protective efficacy in mice and possesses more stability as compared to PA along with the capability of recognizing PA, LF and EF at the same time. Thus, it can be considered as an improved vaccine against anthrax with better shelf life. ID-LFn, a novel multiepitope chimeric anthrax vaccine: ID-LFn comprises of immunodominant epitopes of domain 4 of PA and N-terminal homologous stretch of LF and EF. The administration of this protein as a vaccine provides protection against anthrax.


Assuntos
Vacinas contra Antraz/imunologia , Vacinas contra Antraz/isolamento & purificação , Antraz/prevenção & controle , Antígenos de Bactérias/imunologia , Toxinas Bacterianas/imunologia , Epitopos/imunologia , Animais , Vacinas contra Antraz/administração & dosagem , Vacinas contra Antraz/química , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Toxinas Bacterianas/genética , Dicroísmo Circular , Modelos Animais de Doenças , Estabilidade de Medicamentos , Epitopos/genética , Feminino , Camundongos Endogâmicos BALB C , Análise de Sobrevida , Linfócitos T/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/química , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/isolamento & purificação
14.
Malar J ; 18(1): 346, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31601218

RESUMO

BACKGROUND: Malaria is one of the deadliest infectious diseases caused by protozoan parasite of Plasmodium spp. Increasing resistance to anti-malarials has become global threat in control of the disease and demands for novel anti-malarial interventions. Naturally-occurring coumarins, which belong to a class of benzo-α-pyrones, found in higher plants and some essential oils, exhibit therapeutic potential against various diseases. However, their limited uptake and non-specificity has restricted their wide spread use as potential drug candidates. METHODS: Two series of carbohydrate fused pyrano[3,2-c]pyranone carbohybrids which were synthesized by combination of 2-C-formyl galactal and 2-C-formyl glucal, with various freshly prepared 4-hydroxycoumarins were screened against Plasmodium falciparum. The anti-malarial activity of these carbohybrids was determined by growth inhibition assay on P. falciparum 3D7 strain using SYBR green based fluorescence assay. Haemolytic activity of carbohybrid 12, which showed maximal anti-malarial activity, was determined by haemocompatibility assay. The uptake of the carbohybrid 12 by parasitized erythrocytes was determined using confocal microscopy. Growth progression assays were performed to determine the stage specific effect of carbohybrid 12 treatment on Pf3D7. In silico studies were conducted to explore the mechanism of action of carbohybrid 12 on parasite microtubule dynamics. These findings were further validated by immunofluorescence assay and drug combination assay. RESULTS: 2-C-formyl galactal fused pyrano[3,2-c]pyranone carbohybrid 12 exhibited maximum growth inhibitory potential against Plasmodium with IC50 value of 5.861 µM and no toxicity on HepG2 cells as well as no haemolysis of erythrocytes. An enhanced uptake of this carbohybrid compound was observed by parasitized erythrocytes as compared to uninfected erythrocytes. Further study revealed that carbohybrid 12 arrests the growth of parasite at trophozoite and schizonts stage during course of progression through asexual blood stages. Mechanistically, it was shown that the carbohybrid 12 binds to α,ß-heterodimer of tubulin and affects microtubule dynamics. CONCLUSION: These findings show carbohydrate group fusion to 4-hydroxycoumarin precursor resulted in pyrano-pyranones derivatives with better solubility, enhanced uptake and improved selectivity. This data confirms that, carbohydrate fused pyrano[3,2-c]pyranones carbohybrids are effective candidates for anti-malarial interventions against P. falciparum.


Assuntos
Antimaláricos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Simulação por Computador , Cumarínicos/química , Imunofluorescência , Microtúbulos/efeitos dos fármacos
15.
Mol Cell Biochem ; 430(1-2): 115-125, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28210903

RESUMO

Despite the current progress in cancer research and therapy, breast cancer remains the leading cause of mortality among half a million women worldwide. Migration and invasion of cancer cells are associated with prevalent tumor metastasis as well as high mortality. Extensive studies have powerfully established the role of prototypic second messenger cAMP and its two ubiquitously expressed intracellular cAMP receptors namely the classic protein kinaseA/cAMP-dependent protein kinase (PKA) and the more recently discovered exchange protein directly activated by cAMP/cAMP-regulated guanine nucleotide exchange factor (EPAC/cAMP-GEF) in cell migration, cell cycle regulation, and cell death. Herein, we performed the analysis of the Cancer Genome Atlas (TCGA) dataset to evaluate the essential role of cAMP molecular network in breast cancer. We report that EPAC1, PKA, and AKAP9 along with other molecular partners are amplified in breast cancer patients, indicating the importance of this signaling network. To evaluate the functional role of few of these proteins, we used pharmacological modulators and analyzed their effect on cell migration and cell death in breast cancer cells. Hence, we report that inhibition of EPAC1 activity using pharmacological modulators leads to inhibition of cell migration and induces cell death. Additionally, we also observed that the inhibition of EPAC1 resulted in disruption of its association with the microtubule cytoskeleton and delocalization of AKAP9 from the centrosome as analyzed by in vitro imaging. Finally, this study suggests for the first time the mechanistic insights of mode of action of a primary cAMP-dependent sensor, Exchange protein activated by cAMP 1 (EPAC1), via its interaction with A-kinase anchoring protein 9 (AKAP9). This study provides a new cell signaling cAMP-EPAC1-AKAP9 direction to the development of additional biotherapeutics for breast cancer.


Assuntos
Apoptose , Neoplasias da Mama/metabolismo , Movimento Celular , AMP Cíclico/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Proteínas de Neoplasias/metabolismo , Sistemas do Segundo Mensageiro , Proteínas de Ancoragem à Quinase A/genética , Proteínas de Ancoragem à Quinase A/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Feminino , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Células MCF-7 , Proteínas de Neoplasias/genética
16.
AAPS PharmSciTech ; 18(6): 2188-2202, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28070848

RESUMO

Polyphenon 60 (P60) and curcumin (CUR) were loaded in a single nanoemulsion system and their combined antibacterial action was studied against uropathogenic Escherichia coli. To enhance availability at target organs and to inhibit enzymatic degradation in gastro intestinal tract, vaginal route of administration was explored. P60 + CUR nanoemulsion (NE) was formulated by ultra-sonication and optimized using Box-Behnken design. Optimized NE showed Z-average of 211.2 nm, polydispersity index of 0.343, and zeta potential of -32.7 mV. Optimized P60+ CUR NE was characterized by stability testing and transmission electron microscopy, and it was observed that NE was stable at 4°C for 30 days and monodisperse in nature with particle size of 195-205 nm. P60+ CUR NE was further formulated as gel and characterized by viscosity, growth curve analysis, and in vitro permeation studies. In vitro drug permeation studies in simulated vaginal media showed maximum permeation (84 ± 0.21%) of curcumin within 5 h and (91 ± 0.16%) of P60 within 8 h. Both the drugs maintained sustained permeation for 12 h. To investigate the transport via intravaginal route, gamma scintigraphy and biodistribution study of P60 + CUR NBG was performed on Sprague-Dawley rats using 99mtechnetium pertechnetate for radiolabeling to P60 molecule. Following intravaginal administration, P60 + CUR NBG dispersed in the kidney and urinary bladder with (3.07 ± 0.15) and (3.35 ± 0.45) percentage per gram after 3 h for P60 and CUR, respectively, and remained active for 12 h. Scintigraphy images suggested that the P60 + CUR NBG given by intravaginal route led to effective distribution of actives in urinary tract, and this observation was in agreement with the biodistribution results.


Assuntos
Curcumina , Nanopartículas/uso terapêutico , Fenóis , Administração Intravaginal , Animais , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/farmacocinética , Curcumina/administração & dosagem , Curcumina/farmacocinética , Modelos Animais de Doenças , Portadores de Fármacos , Emulsões , Infecções por Escherichia coli/tratamento farmacológico , Masculino , Tamanho da Partícula , Fenóis/administração & dosagem , Fenóis/farmacocinética , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual , Resultado do Tratamento
17.
Bioorg Med Chem Lett ; 26(17): 4223-32, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27496212

RESUMO

The anti-cancer property of curcumin, an active component of turmeric, is limited due to its poor solubility, stability and bioavailability. To enhance its efficacy, we designed a novel series of twenty-four monocarbonyl curcumin analogue-1,2,3-triazole conjugates and evaluated their anti-cancer activity towards endocrine related cancers. The new compounds (17-40) were synthesized through CuAAC click reaction and SAR analysis carried out. Out of these all, compound 17 showed most significant anti-cancer activity against prostate cancer cells with IC50 values of 8.8µM and 9.5µM in PC-3 and DU-145 cells, respectively. Another compound 26 showed significant anti-cancer activity against breast cancer cells with IC50 of 6µM, 10µM and 6.4µM in MCF-7, MDA-MB-231 and 4T1 cells, respectively while maintaining low toxicity towards non-cancer originated cell line, HEK-293. Compounds 17 and 26 arrested cell cycle and induced mitochondria-mediated apoptosis in cancer cells. Further, both of these compounds significantly down-regulated cell proliferation marker (PCNA), inhibited activation of cell survival protein (Akt phosphorylation), upregulated pro-apoptotic protein (Bax) and down-regulated anti-apoptotic protein (Bcl-2) in their respective cell lines. In addition, in vitro stability, solubility and plasma binding studies of the compounds 17 and 26 showed them to be metabolically stable. Thus, this study identified two new curcumin monocarbonyl-1,2,3-triazole conjugate compounds with more potent activity than curcumin against breast and prostate cancers.


Assuntos
Antineoplásicos/síntese química , Curcumina/química , Triazóis/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Química Click , Regulação para Baixo/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células HEK293 , Meia-Vida , Humanos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Antígeno Nuclear de Célula em Proliferação/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
18.
Bioorg Med Chem Lett ; 25(4): 881-6, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25592712

RESUMO

Prophylactic prevention is considered as the most promising strategy to tackle STI/HIV. Twenty-five dithiocarbamate-thiourea hybrids (14-38) were synthesized as woman controlled topical vaginal microbicides to counter Trichomonas vaginalis and sperm along with RT inhibition potential. The four promising compounds (18, 26, 28 and 33) were tested for safety through cytotoxic assay against human cervical cell line (HeLa) and compatibility with vaginal flora, Lactobacillus. Docking study of most promising vaginal microbicide (33) revealed that it docked in a position and orientation similar to known reverse transcriptase inhibitor Nevirapine. The preliminary in vivo pharmacokinetics of compound 33 was performed in NZ-rabbits to evaluate systemic toxicity in comparison to Nonoxynol-9.


Assuntos
Anti-Infecciosos/farmacologia , Tiocarbamatos/farmacologia , Tioureia/farmacologia , Vagina , Anti-Infecciosos/química , Feminino , HIV/efeitos dos fármacos , Células HeLa , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Tiocarbamatos/química , Tioureia/química , Trichomonas vaginalis/efeitos dos fármacos
19.
Mycoses ; 58(5): 288-93, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25817989

RESUMO

Pulmonary cryptococcosis is likely to be misdiagnosed due to relatively non-specific clinical and radiological features. It is more frequently associated with immuno-suppressed conditions especially acquired immuno-deficiency syndrome (AIDS) and pulmonary tuberculosis (PTB). Four cases of pulmonary cryptococcosis were diagnosed over a period of eleven years. All patients in this case series were human immune-deficiency virus (HIV)-negative. The predisposing factors in these patients were diabetes mellitus (DM), acute lymphoblastic leukaemia (ALL), post-partum and pregnancy in one each of the patients. Relapse was seen in two cases. All the patients survived due to strict follow-up. Pulmonary cryptococcosis is common in non-AIDS patients and it warrants rapid diagnosis, treatment and follow-up to prevent relapse.


Assuntos
Criptococose/diagnóstico , Soronegatividade para HIV , Pneumopatias Fúngicas/diagnóstico , Adulto , Antifúngicos/uso terapêutico , Causalidade , Criança , Criptococose/tratamento farmacológico , Criptococose/etiologia , Criptococose/microbiologia , Complicações do Diabetes , Feminino , Seguimentos , Humanos , Índia , Pneumopatias Fúngicas/tratamento farmacológico , Pneumopatias Fúngicas/etiologia , Pneumopatias Fúngicas/microbiologia , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Infecção Puerperal/diagnóstico , Recidiva , Fatores de Tempo , Adulto Jovem
20.
Bioorg Med Chem Lett ; 24(24): 5782-5786, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25453819

RESUMO

A series of seventeen morpholin/piperidin-1-yl-carbamodithioate (3-19) were synthesized as topical vaginal microbicidal spermicides. The synthesized compounds were evaluated for their anti-Trichomonas activity against MTZ susceptible and resistant strains along with their spermicidal and antifungal potential. All the synthesized compounds were assessed for their safety through cytotoxic assay against human cervical cell line (HeLa) and compatibility with vaginal flora, Lactobacillus. The study identified eleven dually active compounds with apparent safety. The plausible mode of action of these compounds was through sulfhydryl binding, confirmed via reduction in available free thiols on human sperm. The most promising compound 9 significantly inhibited (P<0.001) thiol-sensitive sperm hexokinase. The stability of compound 9 in simulated vaginal fluid (SVF) was performed via HPLC-PDA method, which supported its utility for vaginal administration.


Assuntos
Antifúngicos/síntese química , Desenho de Fármacos , Piperidinas/síntese química , Espermicidas/síntese química , Compostos de Sulfidrila/química , Tiocarbamatos/síntese química , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Feminino , Células HeLa , Hexoquinase/antagonistas & inibidores , Hexoquinase/metabolismo , Humanos , Lactobacillus/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana , Morfolinas/química , Piperidinas/química , Piperidinas/farmacologia , Piperidinas/toxicidade , Espermicidas/farmacologia , Espermicidas/toxicidade , Espermatozoides/efeitos dos fármacos , Espermatozoides/enzimologia , Relação Estrutura-Atividade , Compostos de Sulfidrila/farmacologia , Compostos de Sulfidrila/toxicidade , Tiocarbamatos/farmacologia , Tiocarbamatos/toxicidade , Trichomonas vaginalis/efeitos dos fármacos
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