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1.
Mol Microbiol ; 120(5): 702-722, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37748926

RESUMO

Lipid droplets (LDs) are storage organelles for neutral lipids which are critical for lipid homeostasis. Current knowledge of fungal LD biogenesis is largely limited to budding yeast, while LD regulation in multinucleated filamentous fungi which exhibit considerable metabolic activity remains unexplored. In this study, 19 LD-associated proteins were identified in the multinucleated species Aspergillus oryzae using a colocalization screening of a previously established enhanced green fluorescent protein (EGFP) fusion library. Functional screening identified 12 lipid droplet-regulating (LDR) proteins whose loss of function resulted in irregular LD biogenesis, particularly in terms of LD number and size. Bioinformatics analysis, targeted mutagenesis, and microscopy revealed four LDR proteins that localize to LD via the putative amphipathic helices (AHs). Further analysis revealed that LdrA with an Opi1 domain is essential for cytoplasmic and nuclear LD biogenesis involving a novel AH. Phylogenetic analysis demonstrated that the patterns of gene evolution were predominantly based on gene duplication. Our study identified a set of novel proteins involved in the regulation of LD biogenesis, providing unique molecular and evolutionary insights into fungal lipid storage.


Assuntos
Gotículas Lipídicas , Proteínas , Gotículas Lipídicas/metabolismo , Filogenia , Proteínas/metabolismo , Metabolismo dos Lipídeos/genética , Fungos/metabolismo , Lipídeos
2.
Physiol Plant ; 175(6): e14115, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38148216

RESUMO

Oilseed rape (Brassica napus L.) is a significant agro-economic crop with a wide range of uses. Drought is the most frequent unfavourable environmental stressor restraining its growth and development worldwide. This study was conducted to characterize the drought-responsive phenylpropanoid pathway and its link to hormonal changes in two cultivars, drought-resistant "Saturnin" and drought-susceptible "Mosa." Drought susceptibility in cv. Mosa was confirmed by its lower water use efficiency and higher lipid peroxidation levels with reactive oxygen species (ROS) accumulation. In cv. Saturnin, higher salicylic acid (SA) levels and expression of dehydration-responsive element binding 2 (DREB2) and non-expressor of pathogenesis-related gene 1 (NPR1) led to an upregulation of production of anthocyanin pigment 1 (PAP1) and phenylpropanoid pathway-related gene (CHS, F5H and COMT1) expression, increasing hydroxycinnamic acid and flavonoid compound concentrations. However, in cv. Mosa, higher increases in the activity of lignifying enzymes (polyphenol oxidase, coniferyl alcohol peroxidase, syringaldazine peroxidase, guaiacol peroxidase) and expression of the lignin synthesis-related gene cinnamyl alcohol dehydrogenase 2 (CAD2) were found along with greater increases in abscisic acid (ABA) levels and upregulation of ABA-responsive element binding 2 (AREB2) and basic helix-loop-helix transcription factor MYC2. These results indicate that drought-induced SA-mediated activation of the hydroxycinnamic acid and flavonoid pathways contributes to drought resistance, whereas ABA-mediated lignification contributes to drought susceptibility.


Assuntos
Brassica napus , Resistência à Seca , Brassica napus/genética , Brassica napus/metabolismo , Ácidos Cumáricos/metabolismo , Ácido Abscísico/metabolismo , Secas , Flavonoides/metabolismo
3.
Mol Biol Rep ; 50(9): 7619-7637, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37531035

RESUMO

BACKGROUND: A set of 44 selected Bambara groundnut (Vigna subterranea [L.] Verdc.) accessions was sampled from 11 distinct populations of four geographical zones to assess the genetic drift, population structure, phylogenetic relationship, and genetic differentiation linked with ISSR primers. METHODS AND RESULTS: The amplification of genomic DNA with 32 ISSR markers detected an average of 97.64% polymorphism while 35.15% and 51.08% polymorphism per population and geographical zone, respectively. Analysis of molecular variance revealed significant variation within population 75% and between population 25% whereas within region 84% and between region 16%. The Bidillali exposed greater number of locally common band i.e., NLCB (≤ 25%) = 25 and NLCB (≤ 50%) = 115 were shown by Cancaraki while the lowest was recorded as NLCB (≤ 25%) = 6 and NLCB (≤ 50%) = 72 for Roko and Maibergo, accordingly. The highest PhiPT value was noted between Roko and Katawa (0.405*) whereas Nei's genetic distance was maximum between Roko and Karu (0.124). Based on Nei's genetic distance, a radial phylogenetic tree was constructed that assembled the entire accessions into 3 major clusters for further confirmation unrooted NJ vs NNet split tree analysis based on uncorrected P distance exposed the similar result. Principal coordinate analysis showed variation as PC1 (15.04%) > PC2 (5.81%). CONCLUSIONS: The current study leads to prompting the genetic improvement and future breeding program by maximum utilization and better conservation of existing accessions. The accessions under Cancaraki and Jatau are population documented for future breeding program due to their higher genetic divergence and homozygosity.


Assuntos
Vigna , Vigna/genética , Filogenia , Melhoramento Vegetal , Deriva Genética , Repetições de Microssatélites/genética , Variação Genética/genética
4.
Educ Inf Technol (Dordr) ; 28(6): 7601-7630, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36532794

RESUMO

Following COVID-19, the global educational landscape shifted dramatically. Almost every educational institute in Bangladesh undertook a strategic move to begin offering online or blended learning courses to mitigate the challenges created by the pandemic. The TVET sector, particularly the polytechnic institute of Bangladesh, endeavored to explore the blended learning approach as an immediate and long-term solution to address the educational dislocation caused by the pandemic. This study attempts to conceptualize a pedagogical design based on the ADDIE and rapid prototyping model to make a reliable and robust instructional design to be used in the blended learning context. A content validity index (CVI) was used to validate the proposed model; a technology acceptance model (TAM) was employed to examine its acceptability to students; and finally, students' academic performances were analysed to evaluate the overall performance of the proposed instructional design. The findings reveal that the proposed instructional design can be a reliable and valid pedagogical approach to be implemented in the blended learning context for polytechnic students. The proposed instructional design may help TVET educators and course designers to create a robust blended learning environment in the TVET sector and in other similar disciplines, such as science and engineering education.

5.
Biochem Biophys Res Commun ; 609: 9-14, 2022 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-35413542

RESUMO

The endocannabinoid 2-arachidonoylglycerol (2AG) is an important modulator of stress responses. Its level in the brain increases in response to stress, but region-specific effects of stress on brain 2AG are not well known yet. Moreover, green nut oil (GNO), oil extracted from the seeds of Plukenetia volubilis has several health benefits, but its effects on brain 2AG levels are unknown. Therefore, we conducted this study to explore the effects of stress and GNO supplementation on 2AG levels in specific brain regions of senescence-accelerated mouse prone 8 (SAMP8). In this study, desorption electrospray ionization-mass spectrometry imaging (DESI-MSI) revealed that water-immersion stress for three days significantly increased 2AG levels in several brain regions of SAMP8 mice, including the hypothalamus, midbrain, and hindbrain. No significant change was observed in the relative abundance of brain 2AG in stress given SAMP8 mice after eighteen days of removing stress load compared to control SAMP8 mice. GNO supplementation also increased brain 2AG in SAMP8 mice without stress load. Additionally, GNO supplementation sustained the increased brain 2AG levels in stress given SAMP8 mice after eighteen days of removing stress load. Among all brain regions, a relatively higher accumulation of 2AG was noted in the hypothalamus, midbrain, and hindbrain of GNO-fed SAMP8. Our data explored the potentiality of GNO supplementation to improve brain 2AG levels which might be used to treat anxiety and depressive behaviors.


Assuntos
Encéfalo , Nozes , Envelhecimento , Animais , Ácidos Araquidônicos , Suplementos Nutricionais , Endocanabinoides , Glicerídeos , Hipotálamo , Mesencéfalo , Camundongos , Rombencéfalo
6.
Arch Microbiol ; 204(3): 199, 2022 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-35220488

RESUMO

This study was aimed to evaluate eggplant's growth-enhancing activity of chlorpyrifos and diazinon-degrading endophytic and rhizospheric soil bacteria isolated from cauliflower and tomato roots and the rhizospheric soil of rice roots, respectively. The identified endophytes belong to the Acinetobacter, Enterobacter and Klebsiella genera, while rhizospheric soil isolates belong to Pantoea, Acinetobacter, Kosakonia, Morganella, Enterobacter, and Klebsiella genera with species variation and genetic distances. All the strain's consumed 100% (50 mg/5 mL) chlorpyrifos and diazinon after 14 days of exposure, except for Pantoea sp. HSTU-Sny4 (84%) and Kosakonia sp. HSTU-ASn39 (42%). The strain's exhibited N-fixation, P-solubilization, indole-3-acetic acid (IAA), and ACC-deaminase production capabilities. The individual strain's and consortium treatment enhanced eggplant growth at germination, seedling, vegetative and reproductive stages. Plant growth-promoting genes, e.g., nif-cluster, chemotaxis, phosphates, sulfur, abiotic stress, chemotaxis, biofilm formation and organophosphorus insecticide-degrading genes were annotated in Klebsiella sp. HSTU-Sny5 and Morganella sp. HSTU-ASny43 genomes. Importantly, the mixed consortium supplemented with 40% urea-treated eggplants demonstrated similar growth parameters compared to the 100% urea eggplants. Plenty of insecticide-degrading proteins belonged to HSTU-Sny5 and HSTU-ASny43 strain's and had interacted with 100 different insecticides as confirmed in virtual screening. This research has a significant role in reducing the application of chemical fertilizer and bioremediation of pesticides in agriculture.


Assuntos
Inseticidas , Solanum melongena , Endófitos , Inseticidas/metabolismo , Inseticidas/farmacologia , Compostos Organofosforados/metabolismo , Raízes de Plantas/microbiologia , Solo , Solanum melongena/metabolismo
7.
J Allergy Clin Immunol ; 148(2): 473-485.e10, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33713763

RESUMO

BACKGROUND: Neutrophilic folliculitis is an inflammatory condition of hair follicles. In some neutrophilic folliculitis, such as in patients with acne and hidradenitis suppurativa, follicular hyperkeratosis is also observed. Neutrophilic folliculitis is often induced and/or exacerbated by a high-fat diet (HFD). However, the molecular mechanisms by which an HFD affects neutrophilic folliculitis are not fully understood. OBJECTIVE: Our aim was to elucidate how an HFD promotes the development of neutrophilic folliculitis. METHODS: Mice were fed an HFD, and their skin was subjected to histologic, RNA sequencing, and imaging mass spectrometry analyses. To examine the effect of an HFD on neutrophil accumulation around the hair follicles, phorbol 12-myristate 13-acetate (PMA) was used as an irritant to the skin. RESULTS: Histologic analysis revealed follicular hyperkeratosis in the skin of HFD-fed mice. RNA sequencing analysis showed that genes related to keratinization, especially in upper hair follicular keratinocytes, were significantly upregulated in HFD-fed mice. Application of PMA to the skin induced neutrophilic folliculitis in HFD-fed mice but not in mice fed a normal diet. Accumulation of neutrophils in the skin and around hair follicles was dependent on CXCR2 signaling, and CXCL1 (a CXCR2 ligand) was produced mainly by hair follicular keratinocytes. Imaging mass spectrometry analysis revealed an increase in fatty acids in the skin of HFD-fed mice. Application of these fatty acids to the skin induced follicular hyperkeratosis and caused PMA-induced neutrophilic folliculitis even in mice fed a normal diet. CONCLUSION: An HFD can facilitate the development of neutrophilic folliculitis with the induction of hyperkeratosis of hair follicles and increased neutrophil infiltration around the hair follicles via CXCR2 signaling.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Foliculite/imunologia , Folículo Piloso/imunologia , Hiperceratose Epidermolítica/imunologia , Infiltração de Neutrófilos/efeitos dos fármacos , Animais , Suscetibilidade a Doenças/induzido quimicamente , Suscetibilidade a Doenças/imunologia , Suscetibilidade a Doenças/patologia , Foliculite/induzido quimicamente , Foliculite/patologia , Folículo Piloso/patologia , Hiperceratose Epidermolítica/induzido quimicamente , Hiperceratose Epidermolítica/patologia , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/patologia , Masculino , Camundongos
8.
Educ Inf Technol (Dordr) ; 27(2): 2241-2265, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34413694

RESUMO

Digital transformation and emerging technologies open a horizon to a new method of teaching and learning and revolutionizes the e-learning industry. The goal of this study is to scrutinize a proposed research model for predicting factors that influence student's behavioral intention to use e-learning system at Begum Rokeya University, Bangladesh. The study used quantitative approach and developed a research model based on several technological acceptance models. In order to test the model, a survey was conducted to obtain data from 262 university students. SEM-PLS, a multivariate statistical analysis technique, was used to analyze the responses to examine the model, factors, structural relationships, and hypotheses. The result shows that 'perceived usefulness' and 'perceived ease of use' positively and significantly influenced by 'perceived enjoyment'. Furthermore, 'perceived usefulness', 'perceived ease of use' and 'facilitating condition' have a significant impact to predict behavioral intention to use e-learning. The results of mediation analysis show that 'perceived usefulness' and 'perceived ease of use' have mediating effects between the predictors and the outcome. Finally, 'facilitating condition' have a remarkable moderating effect to predict the student's behavioral intention in using e-learning. The findings have a noteworthy empirical implication for educational institutions to introduce e-learning system as one of the teaching and learning tools.

9.
Educ Inf Technol (Dordr) ; 27(1): 1261-1286, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34257512

RESUMO

The COVID-19 pandemic makes flipped learning more relevant to address the challenges of remote learning. Therefore, renewed attention is warranted in critically appraising the implications on which flipped learning is built. Though several studies have reviewed the flipped learning research in the past, the majority has qualitatively synthesized the flipped learning literature, thus, lacking the overall perspective provided quantitatively for appraising the existing state of affairs of flipped learning research in engineering education. This study addresses this gap by objectively mapping the conceptual, intellectual, and social structure of research development in flipped learning using a bibliometric review method. Findings reveal that flipped learning in engineering education is a relatively new field of research and in recent time it has entered into the stage of exponential growth. Findings also show the effectiveness of the flipped learning model to address the challenges of complex pedagogical applications in different fields of engineering education. This study provides a quantitative synopsis of the flipped learning literature which can be used as an anchor for future study.

10.
Circ Res ; 125(3): 309-327, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31195886

RESUMO

RATIONALE: Pulmonary arterial hypertension (PAH) is characterized by enhanced proliferation of pulmonary artery smooth muscle cells (PASMCs) accompanying increased production of inflammatory factors and adaptation of the mitochondrial metabolism to a hyperproliferative state. However, all the drugs in clinical use target pulmonary vascular dilatation, which may not be effective for patients with advanced PAH. OBJECTIVE: We aimed to discover a novel drug for PAH that inhibits PASMC proliferation. METHODS AND RESULTS: We screened 5562 compounds from original library using high-throughput screening system to discover compounds which inhibit proliferation of PASMCs from patients with PAH (PAH-PASMCs). We found that celastramycin, a benzoyl pyrrole-type compound originally found in a bacteria extract, inhibited the proliferation of PAH-PASMCs in a dose-dependent manner with relatively small effects on PASMCs from healthy donors. Then, we made 25 analogs of celastramycin and selected the lead compound, which significantly inhibited cell proliferation of PAH-PASMCs and reduced cytosolic reactive oxygen species levels. Mechanistic analysis demonstrated that celastramycin reduced the protein levels of HIF-1α (hypoxia-inducible factor 1α), which impairs aerobic metabolism, and κB (nuclear factor-κB), which induces proinflammatory signals, in PAH-PASMCs, leading to reduced secretion of inflammatory cytokine. Importantly, celastramycin treatment reduced reactive oxygen species levels in PAH-PASMCs with increased protein levels of Nrf2 (nuclear factor erythroid 2-related factor 2), a master regulator of cellular response against oxidative stress. Furthermore, celastramycin treatment improved mitochondrial energy metabolism with recovered mitochondrial network formation in PAH-PASMCs. Moreover, these celastramycin-mediated effects were regulated by ZFC3H1 (zinc finger C3H1 domain-containing protein), a binding partner of celastramycin. Finally, celastramycin treatment ameliorated pulmonary hypertension in 3 experimental animal models, accompanied by reduced inflammatory changes in the lungs. CONCLUSIONS: These results indicate that celastramycin ameliorates pulmonary hypertension, reducing excessive proliferation of PAH-PASMCs with less inflammation and reactive oxygen species levels, and recovered mitochondrial energy metabolism. Thus, celastramycin is a novel drug for PAH that targets antiproliferative effects on PAH-PASMCs.


Assuntos
Miócitos de Músculo Liso/efeitos dos fármacos , Naftoquinonas/farmacologia , Hipertensão Arterial Pulmonar/tratamento farmacológico , Pirróis/farmacologia , Resorcinóis/farmacologia , Animais , Células Cultivadas , Citocinas/biossíntese , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Metabolismo Energético/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Humanos , Hipóxia/complicações , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Indóis/toxicidade , Masculino , Metaboloma/efeitos dos fármacos , Camundongos , Mitocôndrias/efeitos dos fármacos , Monocrotalina/toxicidade , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/biossíntese , Naftoquinonas/uso terapêutico , Estresse Oxidativo , Hipertensão Arterial Pulmonar/induzido quimicamente , Artéria Pulmonar/citologia , Pirróis/uso terapêutico , Pirróis/toxicidade , Ratos , Espécies Reativas de Oxigênio/metabolismo , Resorcinóis/uso terapêutico , Fatores de Transcrição/fisiologia
11.
Circ Res ; 125(10): 884-906, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31556812

RESUMO

RATIONALE: Pulmonary arterial hypertension (PAH) is characterized by pulmonary vascular remodeling with aberrant pulmonary artery smooth muscle cells (PASMCs) proliferation, endothelial dysfunction, and extracellular matrix remodeling. OBJECTIVE: Right ventricular (RV) failure is an important prognostic factor in PAH. Thus, we need to elucidate a novel therapeutic target in both PAH and RV failure. METHODS AND RESULTS: We performed microarray analysis in PASMCs from patients with PAH (PAH-PASMCs) and controls. We found a ADAMTS8 (disintegrin and metalloproteinase with thrombospondin motifs 8), a secreted protein specifically expressed in the lung and the heart, was upregulated in PAH-PASMCs and the lung in hypoxia-induced pulmonary hypertension (PH) in mice. To elucidate the role of ADAMTS8 in PH, we used vascular smooth muscle cell-specific ADAMTS8-knockout mice (ADAMTSΔSM22). Hypoxia-induced PH was attenuated in ADAMTSΔSM22 mice compared with controls. ADAMTS8 overexpression increased PASMC proliferation with downregulation of AMPK (AMP-activated protein kinase). In contrast, deletion of ADAMTS8 reduced PASMC proliferation with AMPK upregulation. Moreover, deletion of ADAMTS8 reduced mitochondrial fragmentation under hypoxia in vivo and in vitro. Indeed, PASMCs harvested from ADAMTSΔSM22 mice demonstrated that phosphorylated DRP-1 (dynamin-related protein 1) at Ser637 was significantly upregulated with higher expression of profusion genes (Mfn1 and Mfn2) and improved mitochondrial function. Moreover, recombinant ADAMTS8 induced endothelial dysfunction and matrix metalloproteinase activation in an autocrine/paracrine manner. Next, to elucidate the role of ADAMTS8 in RV function, we developed a cardiomyocyte-specific ADAMTS8 knockout mice (ADAMTS8ΔαMHC). ADAMTS8ΔαMHC mice showed ameliorated RV failure in response to chronic hypoxia. In addition, ADAMTS8ΔαMHC mice showed enhanced angiogenesis and reduced RV ischemia and fibrosis. Finally, high-throughput screening revealed that mebendazole, which is used for treatment of parasite infections, reduced ADAMTS8 expression and cell proliferation in PAH-PASMCs and ameliorated PH and RV failure in PH rodent models. CONCLUSIONS: These results indicate that ADAMTS8 is a novel therapeutic target in PAH.


Assuntos
Proteínas ADAMTS/deficiência , Insuficiência Cardíaca/metabolismo , Hipertensão Arterial Pulmonar/metabolismo , Disfunção Ventricular Direita/metabolismo , Proteínas ADAMTS/antagonistas & inibidores , Proteínas ADAMTS/genética , Adulto , Animais , Células Cultivadas , Sistemas de Liberação de Medicamentos/tendências , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/patologia , Humanos , Masculino , Mebendazol/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Hipertensão Arterial Pulmonar/tratamento farmacológico , Hipertensão Arterial Pulmonar/patologia , Distribuição Aleatória , Disfunção Ventricular Direita/tratamento farmacológico , Disfunção Ventricular Direita/patologia
12.
Proc Natl Acad Sci U S A ; 115(30): E7129-E7138, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-29987023

RESUMO

Although postcapillary pulmonary hypertension (PH) is an important prognostic factor for patients with heart failure (HF), its pathogenesis remains to be fully elucidated. To elucidate the different roles of Rho-kinase isoforms, ROCK1 and ROCK2, in cardiomyocytes in response to chronic pressure overload, we performed transverse aortic constriction (TAC) in cardiac-specific ROCK1-deficient (cROCK1-/-) and ROCK2-deficient (cROCK2-/-) mice. Cardiomyocyte-specific ROCK1 deficiency promoted pressure-overload-induced cardiac dysfunction and postcapillary PH, whereas cardiomyocyte-specific ROCK2 deficiency showed opposite results. Histological analysis showed that pressure-overload-induced cardiac hypertrophy and fibrosis were enhanced in cROCK1-/- mice compared with controls, whereas cardiac hypertrophy was attenuated in cROCK2-/- mice after TAC. Consistently, the levels of oxidative stress were up-regulated in cROCK1-/- hearts and down-regulated in cROCK2-/- hearts compared with controls after TAC. Furthermore, cyclophilin A (CyPA) and basigin (Bsg), both of which augment oxidative stress, enhanced cardiac dysfunction and postcapillary PH in cROCK1-/- mice, whereas their expressions were significantly lower in cROCK2-/- mice. In clinical studies, plasma levels of CyPA were significantly increased in HF patients and were higher in patients with postcapillary PH compared with those without it. Finally, high-throughput screening demonstrated that celastrol, an antioxidant and antiinflammatory agent, reduced the expressions of CyPA and Bsg in the heart and the lung, ameliorating cardiac dysfunction and postcapillary PH induced by TAC. Thus, by differentially affecting CyPA and Bsg expressions, ROCK1 protects and ROCK2 jeopardizes the heart from pressure-overload HF with postcapillary PH, for which celastrol may be a promising agent.


Assuntos
Cardiomegalia/metabolismo , Insuficiência Cardíaca/metabolismo , Hipertensão Pulmonar/metabolismo , Pulmão/metabolismo , Miocárdio/metabolismo , Quinases Associadas a rho/metabolismo , Animais , Basigina/biossíntese , Basigina/genética , Cardiomegalia/genética , Cardiomegalia/patologia , Ciclofilina A/biossíntese , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/patologia , Pulmão/patologia , Camundongos , Camundongos Knockout , Miocárdio/patologia , Quinases Associadas a rho/genética
13.
J Cell Mol Med ; 24(4): 2542-2551, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31919976

RESUMO

The total flavonoids from Tridax procumbens (TPFs) have been reported significantly to suppress on RANKL-induced osteoclast differentiation and bone resorption in mouse primary cultured osteoclasts. However, the effects of ethyl ether fraction of Tridax procumbens flavonoids (TPF) on osteoclastogenesis remain unknown. In this study, we investigated the effects of TPF on lipopolysaccharides (LPS)-induced osteoclast differentiation, actin ring formation, and explored its molecular mechanism in vitro. Matured osteoclast was counted as the number of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells, and activity of osteoclast was assessed by performing the pit formation assays. Real-time polymerase chain reaction (RT-PCR) was performed for evaluation of the expression of osteoclast differentiation-related genes. TPF reduced the TRAP-positive multinucleated osteoclasts, inhibited TRAP and acid phosphatase (ACP) activities and decreased the expression of osteoclast differentiating genes, including cathepsin K, metalloproteinase-2 (MMP-2), MMP-9, MMP-13 and osteoclast-associated receptor (OSCAR). Furthermore, osteoclast-dependent actin rings formation and resorption pits were dramatically inhibited by the treatment with TPF. TPF markedly decreased the expression levels of transcription factors such as c-Fos, nuclear factor of activated T cells cytoplasmic 1 (NFATc1) and activator protein-1 (AP-1). Taken together, our findings indicated that TPF suppressed both osteoclast differentiation and activities. Therefore, TPF might be a promising and emerging drug candidate for the treatment of bone diseases such as osteoporosis.


Assuntos
Asteraceae/química , Diferenciação Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Flavonoides/farmacologia , Osteoclastos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Animais , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/metabolismo , Feminino , Metaloendopeptidases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Osteoclastos/metabolismo , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo
14.
Arterioscler Thromb Vasc Biol ; 39(11): 2367-2385, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31533472

RESUMO

OBJECTIVE: Excessive proliferation and apoptosis resistance are special characteristics of pulmonary artery smooth muscle cells (PASMCs) in pulmonary arterial hypertension (PAH). However, the drugs in clinical use for PAH target vascular dilatation, which do not exert adequate effects in patients with advanced PAH. Here, we report a novel therapeutic effect of emetine, a principal alkaloid extracted from the root of ipecac clinically used as an emetic and antiprotozoal drug. Approach and Results: We performed stepwise screenings for 5562 compounds from original library. First, we performed high-throughput screening with PASMCs from patients with PAH (PAH-PASMCs) and found 80 compounds that effectively inhibited proliferation. Second, we performed the repeatability and counter assay. Finally, we performed a concentration-dependent assay and found that emetine inhibits PAH-PASMC proliferation. Interestingly, emetine significantly reduced protein levels of HIFs (hypoxia-inducible factors; HIF-1α and HIF-2α) and downstream PDK1 (pyruvate dehydrogenase kinase 1). Moreover, emetine significantly reduced the protein levels of RhoA (Ras homolog gene family, member A), Rho-kinases (ROCK1 and ROCK2 [rho-associated coiled-coil containing protein kinases 1 and 2]), and their downstream CyPA (cyclophilin A), and Bsg (basigin) in PAH-PASMCs. Consistently, emetine treatment significantly reduced the secretion of cytokines/chemokines and growth factors from PAH-PASMCs. Interestingly, emetine reduced protein levels of BRD4 (bromodomain-containing protein 4) and downstream survivin, both of which are involved in many cellular functions, such as cell cycle, apoptosis, and inflammation. Finally, emetine treatment ameliorated pulmonary hypertension in 2 experimental rat models, accompanied by reduced inflammatory changes in the lungs and recovered right ventricular functions. CONCLUSIONS: Emetine is an old but novel drug for PAH that reduces excessive proliferation of PAH-PASMCs and improves right ventricular functions.


Assuntos
Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Emetina/farmacologia , Emetina/uso terapêutico , Hipertensão Pulmonar/tratamento farmacológico , Músculo Liso Vascular/efeitos dos fármacos , Animais , Basigina/metabolismo , Proteínas Sanguíneas/metabolismo , Ciclofilina A/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Regulação para Baixo , Descoberta de Drogas , Ensaios de Triagem em Larga Escala , Humanos , Hipertensão Pulmonar/fisiopatologia , Masculino , Mitocôndrias Musculares/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Artéria Pulmonar , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Quinases Associadas a rho/metabolismo
15.
Circulation ; 138(6): 600-623, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-29636330

RESUMO

BACKGROUND: Excessive proliferation and apoptosis resistance of pulmonary artery smooth muscle cells (PASMCs) are key mechanisms of pulmonary arterial hypertension (PAH). Despite the multiple combination therapy, a considerable number of patients develop severe pulmonary hypertension (PH) because of the lack of diagnostic biomarker and antiproliferative therapies for PASMCs. METHODS: Microarray analyses were used to identify a novel therapeutic target for PAH. In vitro experiments, including lung and serum samples from patients with PAH, cultured PAH-PASMCs, and high-throughput screening of 3336 low-molecular-weight compounds, were used for mechanistic study and exploring a novel therapeutic agent. Five genetically modified mouse strains, including PASMC-specific selenoprotein P (SeP) knockout mice and PH model rats, were used to study the role of SeP and therapeutic capacity of the compounds for the development of PH in vivo. RESULTS: Microarray analysis revealed a 32-fold increase in SeP in PAH-PASMCs compared with control PASMCs. SeP is a widely expressed extracellular protein maintaining cellular metabolism. Immunoreactivity of SeP was enhanced in the thickened media of pulmonary arteries in PAH. Serum SeP levels were also elevated in patients with PH compared with controls, and high serum SeP predicted poor outcome. SeP-knockout mice ( SeP-/-) exposed to chronic hypoxia showed significantly reduced right ventricular systolic pressure, right ventricular hypertrophy, and pulmonary artery remodeling compared with controls. In contrast, systemic SeP-overexpressing mice showed exacerbation of hypoxia-induced PH. Furthermore, PASMC-specific SeP-/- mice showed reduced hypoxia-induced PH compared with controls, whereas neither liver-specific SeP knockout nor liver-specific SeP-overexpressing mice showed significant differences with controls. Altogether, protein levels of SeP in the lungs were associated with the development of PH. Mechanistic experiments demonstrated that SeP promotes PASMC proliferation and resistance to apoptosis through increased oxidative stress and mitochondrial dysfunction, which were associated with activated hypoxia-inducible factor-1α and dysregulated glutathione metabolism. It is important to note that the high-throughput screening of 3336 compounds identified that sanguinarine, a plant alkaloid with antiproliferative effects, reduced SeP expression and proliferation in PASMCs and ameliorated PH in mice and rats. CONCLUSIONS: These results indicate that SeP promotes the development of PH, suggesting that it is a novel biomarker and therapeutic target of the disorder.


Assuntos
Pressão Arterial , Hipertensão Pulmonar/etiologia , Hipóxia/complicações , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Selenoproteína P/metabolismo , Remodelação Vascular , Animais , Anti-Hipertensivos/farmacologia , Apoptose , Pressão Arterial/efeitos dos fármacos , Benzofenantridinas/farmacologia , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Humanos , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/prevenção & controle , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isoquinolinas/farmacologia , Masculino , Camundongos Knockout , Mitocôndrias Musculares/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/fisiopatologia , Miócitos de Músculo Liso/efeitos dos fármacos , Estresse Oxidativo , Artéria Pulmonar/metabolismo , Artéria Pulmonar/fisiopatologia , Ratos Sprague-Dawley , Transdução de Sinais , Remodelação Vascular/efeitos dos fármacos
16.
Circulation ; 138(21): 2413-2433, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-29921611

RESUMO

BACKGROUND: Thoracic aortic aneurysm (TAA) and dissection are fatal diseases that cause aortic rupture and sudden death. The small GTP-binding protein GDP dissociation stimulator (SmgGDS) is a crucial mediator of the pleiotropic effects of statins. Previous studies revealed that reduced force generation in aortic smooth muscle cells (AoSMCs) causes TAA and thoracic aortic dissection. METHODS: To examine the role of SmgGDS in TAA formation, we used an angiotensin II (1000 ng·min-1·kg-1, 4 weeks)-induced TAA model. RESULTS: We found that 33% of Apoe-/- SmgGDS+/- mice died suddenly as a result of TAA rupture, whereas there was no TAA rupture in Apoe-/- control mice. In contrast, there was no significant difference in the ratio of abdominal aortic aneurysm rupture between the 2 genotypes. We performed ultrasound imaging every week to follow up the serial changes in aortic diameters. The diameter of the ascending aorta progressively increased in Apoe-/- SmgGDS+/- mice compared with Apoe-/- mice, whereas that of the abdominal aorta remained comparable between the 2 genotypes. Histological analysis of Apoe-/- SmgGDS+/- mice showed dissections of major thoracic aorta in the early phase of angiotensin II infusion (day 3 to 5) and more severe elastin degradation compared with Apoe-/- mice. Mechanistically, Apoe-/- SmgGDS+/- mice showed significantly higher levels of oxidative stress, matrix metalloproteinases, and inflammatory cell migration in the ascending aorta compared with Apoe-/- mice. For mechanistic analyses, we primary cultured AoSMCs from the 2 genotypes. After angiotensin II (100 nmol/L) treatment for 24 hours, Apoe-/- SmgGDS+/- AoSMCs showed significantly increased matrix metalloproteinase activity and oxidative stress levels compared with Apoe-/- AoSMCs. In addition, SmgGDS deficiency increased cytokines/chemokines and growth factors in AoSMCs. Moreover, expressions of fibrillin-1 ( FBN1), α-smooth muscle actin ( ACTA2), myosin-11 ( MYH11), MYLLK, and PRKG1, which are force generation genes, were significantly reduced in Apoe-/- SmgGDS+/- AoSMCs compared with Apoe-/- AoSMCs. A similar tendency was noted in AoSMCs from patients with TAA compared with those from control subjects. Finally, local delivery of the SmgGDS gene construct reversed the dilation of the ascending aorta in Apoe-/- SmgGDS+/- mice. CONCLUSIONS: These results suggest that SmgGDS is a novel therapeutic target for the prevention and treatment of TAA.


Assuntos
Aorta/metabolismo , Aneurisma da Aorta Torácica/patologia , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Actinas/genética , Actinas/metabolismo , Angiotensina II/administração & dosagem , Angiotensina II/efeitos adversos , Animais , Aorta/citologia , Aorta/patologia , Aneurisma da Aorta Torácica/metabolismo , Aneurisma da Aorta Torácica/prevenção & controle , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Fibrilina-1/genética , Fibrilina-1/metabolismo , Fatores de Troca do Nucleotídeo Guanina/deficiência , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Proteína Smad4/genética , Proteína Smad4/metabolismo , Proteína rhoA de Ligação ao GTP/genética
17.
Ecotoxicol Environ Saf ; 167: 450-458, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30368138

RESUMO

Full profile of polychlorinated biphenyls (PCBs) in the coastal surface water from Bangladesh were analyzed by GC-MS/MS to explore the status of contamination, spatiotemporal distribution and to trace their potential sources. The total concentrations of dissolved PCBs (∑PCBs, sum of all congeners) varied from 32.17 to 160.7 ng/L and 46.45-199.4 ng/L in winter and summer, respectively, and the ranges were comparable to or higher than those recorded in the surface water from the coastal areas of India, China, Japan, Italy, Belgium and USA. The difference in the levels of PCBs between the two seasons was not statistically significant (p > 0.05). However, spatial distribution revealed that the areas with recent urbanization and industrialization (Chittagong, Cox's Bazar and Sundarbans) were more contaminated with PCBs than the unindustrialized area (Meghna Estuary). Lightly to moderately chlorinated (2-6 Cl) homologs dominated the PCB profiles. Our analyses (congener profile and homolog composition) elucidated that the past and on-going use of PCB-containing equipment (e.g. capacitors and transformers) as well as the anthropogenic activities such as urban developments, commercial and industrial establishments (e.g. ship breaking and port activities) might be the potential sources of PCB emission in Bangladesh. A set of congeners based on their detection frequencies and abundance were identified and categorized as potential environmental marker PCBs, which can be used for the future selective monitoring studies regarding reasonable limitations on full congener assessment. According to the existing national and international water quality guidelines/standards, PCB concentrations recorded in this study could potentially cause biological damage. Essentially, the findings of this first comprehensive report on the PCB contamination in the surface water in Bangladesh may provide a reference to future studies of these compounds in the Bay of Bengal.


Assuntos
Baías/química , Bifenilos Policlorados/análise , Poluentes Químicos da Água/análise , Bangladesh , Cromatografia Gasosa , Monitoramento Ambiental , Sedimentos Geológicos/química , Estações do Ano , Água do Mar/química , Extração em Fase Sólida , Espectrometria de Massas em Tandem
18.
Ecotoxicol Environ Saf ; 178: 17-24, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-30986628

RESUMO

Understanding the trophic movement and trophic magnification factor (TMF) of polycyclic aromatic hydrocarbons (PAHs) is an important criterion to assess their fate and potential effects in an aquatic ecosystem. This study investigated concentrations and trophodynamics of 16 priority PAHs in food webwb (food web comprising whole bodies) and food webm (food web containing only muscles) of total 14 species ((including plankton, shrimp, whitebait, mussels, snails, red-eared terrapin and seven other fish species) from the Dianshan Lake. Values of δ13C and δ15N were determined to assign trophic levels to organisms. In general, there was no evidence of biomagnification because of biological degradation of PAHs compounds, but only 9 PAH compounds in food webm showed a statistically significant negative relationship between trophic level and lipid normalized concentration compared to the 6 PAHs congeners in food webwb. However, TMF values of PAHs in food webm ranged from 0.32 for pyrene to 0.68 for phenanthrene compared to TMF values of food webwb ranged from 0.34 for pyrene to 0.74 for fluorene. Because of two opposing scientific views for biomagnification and biodilution of PAHs in the food web, albeit based on a rather limited number of studies, our study investigated that there is parabolic behavior of most of the PAHs. Concentrations of PAHs in the red-eared terrapin (Trachemys scripta elegans) were biodiluted which showed that this species metabolises such compounds. There was no particular relationship between Kow and TMFs of PAHs in the Dianshan Lake. Hepatobiliary system (such as gall bladder and liver) in the whole body considered to have higher bioaccumulation potential of organic compounds than extrahepatic tissue (muscles).


Assuntos
Organismos Aquáticos/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Lagos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Urbanização , Poluentes Químicos da Água/análise , Animais , China , Cadeia Alimentar
19.
Arch Environ Contam Toxicol ; 76(2): 178-190, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30259080

RESUMO

The surficial sediments were collected in winter and summer (2015) from the coastal areas of Bangladesh and analyzed for 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs). The total concentration of PAHs (∑PAHs) were 349.8-11,058.8 and 199.9-17,089.1 ng/g dry weight (dw) in winter and summer, respectively. Sediements from the areas with recent urbanization and industrialization (Chittagong, Cox's Bazar, and Sundarbans) were more contaminated with PAHs than the unindustrialized area (Meghna Estuary). The concentrations of ∑PAHs were slightly higher in summer than those in winter, but the seasonal variations were not statistically significant (p > 0.05). Molecular ratios suggested mixed sources of PAHs in the Bangladeshi coastal areas with a slight imposition of pyrolytic inputs closely related to shipping and fishing activities as well as industrial and municipal sewage discharge. According to ecological risk assessment, the measured levels of sedimentary PAHs exceeded some of the existing national and international environmental quality guidelines/standards, and thus might cause acute biological damage in the studied areas of the Bay of Bengal coast of Bangladesh.


Assuntos
Sedimentos Geológicos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Poluentes Químicos da Água/análise , Bangladesh , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Estações do Ano , Poluentes Químicos da Água/toxicidade
20.
Environ Geochem Health ; 41(3): 1105-1121, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30288647

RESUMO

Levels, distribution, possible sources and potential risks of 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs) were investigated comprehensively in frequently consumed seafood species collected from the coastal areas of Bangladesh. Samples were collected in winter and summer, 2015. The total concentration of PAHs (∑PAHs) in the examined seafood was 184.5-2806.6 ng/g wet weight (ww) in winter and 117.9-4216.8 ng/g ww in summer, respectively. The levels of ∑PAHs were comparable to or higher than those reported from other coastal areas. Seasonal variation was not significant for the majority of the monitored PAHs. Spatial distribution revealed that the seafood collected from areas with recent urbanization and industrialization (Chittagong, Cox's Bazar and Sundarbans) was more contaminated with PAHs than those from the unindustrialized area (Meghna Estuary). Low-molecular-weight isomers dominated the PAH composition. Molecular ratios suggested the abundance of mixed sources of PAHs in the Bangladeshi coastal areas with a slight imposition toward the petrogenic origin. A preliminary evaluation of human health risk indicated that the dietary PAH exposure from consumption of Bangladeshi seafood would certainly induce adverse health effects. This finding suggests the need to enhance risk management regarding seafood consumption through public advisory in Bangladesh.


Assuntos
Contaminação de Alimentos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Adulto , Bangladesh , Criança , Exposição Dietética/efeitos adversos , Humanos , Peso Molecular , Hidrocarbonetos Policíclicos Aromáticos/química , Medição de Risco , Estações do Ano , Urbanização
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