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MicroRNA (miRNA) genes generally share many features common to those of protein coding genes. Various transcription factors (TFs) and co-regulators are also known to regulate miRNA genes. Here we identify novel p53 and NFκB p65/RelA responsive miRNAs and demonstrate that these 2 TFs bind to the regulatory sequences of miR-100, -146a and -150 in both mouse striatal and human cervical carcinoma cells and regulate their expression. p53 represses the miRNAs while NFκB p65/RelA induces them. Further, we provide evidence that exogenous p53 inhibits NFκB p65/RelA activity by reducing its nuclear content and competing with it for CBP binding. This suggests for the existence of a functional cross-talk between the 2 TFs in regulating miRNA expression. Moreover, promoter occupancy assay reveals that exogenous p53 excludes NFκB p65/RelA from its binding site in the upstream sequence of miR-100 gene thereby causing its repression. Thus, our work identifies novel p53 and NFκB p65/RelA responsive miRNAs in human and mouse and uncovers possible mechanisms of co-regulation of miR-100. It is to be mentioned here that cross-talks between p53 and NFκB p65/RelA have been observed to define the outcome of several biological processes and that the pro-apoptotic effect of p53 and the pro-survival functions of NFκB can be largely mediated via the biological roles of the miRNAs these TFs regulate. Our observation with cell lines thus provides an important platform upon which further work is to be done to establish the biological significance of such co-regulation of miRNAs by p53 and NFκB p65/RelA.
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Regulação da Expressão Gênica , MicroRNAs/genética , Fator de Transcrição RelA/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Linhagem Celular Tumoral , Células HeLa , Humanos , Camundongos , MicroRNAs/metabolismo , Regiões Promotoras GenéticasRESUMO
Hydrodynamics-based gene delivery (HGD) is a widely recognized technique for delivering exogenous DNA with high efficiency to murine hepatocytes. In this study, we investigated stimulation of exogenous DNA uptake and expression using a commercially available reagent for HGD. We also examined which mouse strain and mouse liver lobe would achieve the best gene delivery performance. Mice were injected with a solution containing reporter plasmid DNA or DNA and a gene delivery reagent. One day after the HGD procedure, liver samples were isolated and subjected to biochemical and histochemical analyses. The reporter plasmid DNA showed the strongest signal when the DNA was dissolved in TransIT-EE Hydrodynamic Delivery Solution (Takara Bio Inc., Shiga, Japan). Evaluation of transgene expression in each hepatic lobe in ICR, C57BL/6N, Balb/cA, and B6C3F1 mice showed that ICR mice exhibited the best gene transfer and that the right median lobe had the highest level of transgene expression. These findings suggest the importance of choice in mouse strains and liver lobes when performing gene-based manipulations of the liver.
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Técnicas de Transferência de Genes , Fígado/fisiologia , Animais , Expressão Gênica , Fígado/química , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Especificidade da EspécieRESUMO
Pancreatic angiotensin-converting enzyme 2 (ACE2) has previously been shown to be critical for maintaining glycemia and ß-cell function. Efforts to maintain or increase ACE2 expression in pancreatic ß-cells might therefore have therapeutic potential for treating diabetes. In our study, we investigated the transcriptional role of hepatocyte nuclear factor 1α (HNF1α) and hepatocyte nuclear factor 1ß (HNF1ß) in induction of ACE2 expression in insulin-secreting cells. A deficient allele of HNF1α or HNF1ß causes maturity-onset diabetes of the young (MODY) types 3 and 5, respectively, in humans. We found that ACE2 is primarily transcribed from the proximal part of the ACE2 promoter in the pancreas. In the proximal part of the human ACE2 promoter, we further identified three functional HNF1 binding sites, as they have binding affinity for HNF1α and HNF1ß and are required for induction of promoter activity by HNF1ß in insulinoma cells. These three sites are well-conserved among mammalian species. Both HNF1α and HNF1ß induce expression of ACE2 mRNA and lead to elevated levels of ACE2 protein and ACE2 enzymatic activity in insulinoma cells. Furthermore, HNF1α dose-dependently increases ACE2 expression in primary pancreatic islet cells. We conclude that HNF1α can induce the expression of ACE2 in pancreatic islet cells via evolutionarily conserved HNF1 binding sites in the ACE2 promoter. Potential therapeutics aimed at counteracting functional HNF1α depletion in diabetes and MODY3 will thus have ACE2 induction in pancreatic islets as a likely beneficial effect.
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Evolução Molecular , Fator 1-alfa Nuclear de Hepatócito/fisiologia , Ilhotas Pancreáticas/enzimologia , Peptidil Dipeptidase A/metabolismo , Enzima de Conversão de Angiotensina 2 , Animais , Sequência de Bases , Linhagem Celular Tumoral , Primers do DNA , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Peptidil Dipeptidase A/genética , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Phenotypic switching of smooth muscle cells (SMCs) plays a central role in the development of vascular diseases such as atherosclerosis and restenosis. However, the factors regulating expression of the human myocardin (Myocd) gene, the master gene regulator of SMC differentiation, have yet to be identified. In this study, we sought to identify the critical factors regulating Myocd expression in human SMCs. Using deletion/genetic reporter analyses, an upstream repressor region (URR) was localised within the Myocd promoter, herein termed PrmM. Bioinformatic analysis revealed three evolutionary conserved Klf4 sites within the URR and disruption of those elements led to substantial increases in PrmM-directed gene expression. Furthermore, ectopic expression established that Klf4 significantly decreased Myocd mRNA levels and PrmM-directed gene expression while electrophoretic mobility shift assays and chromatin immunoprecipitation (ChIP) assays confirmed specific binding of endogenous Klf4, and not Klf5 or Klf2, to the URR of PrmM. Platelet-derived growth factor BB (PDGF-BB), a potent inhibitor of SMC differentiation, reduced Myocd mRNA levels and PrmM-directed gene expression in SMCs. A PDGF-BB-responsive region (PRR) was also identified within PrmM, overlapping with the previously identified URR, where either siRNA knockdown of Klf4 or the combined disruption of the Klf4 elements completely abolished PDGF-BB-mediated repression of PrmM-directed gene expression in SMCs. Moreover, ChIP analysis established that PDGF-BB-induced repression of Myocd gene expression is most likely regulated by enhanced binding of Klf4 and Klf5 to a lesser extent, to the PRR of PrmM. Taken together, these data provide critical insights into the transcriptional regulation of the Myocd gene in vascular SMCs, including during SMC differentiation.
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Regulação da Expressão Gênica/efeitos dos fármacos , Fatores de Transcrição Kruppel-Like/metabolismo , Músculo Liso Vascular/metabolismo , Proteínas Nucleares/genética , Transativadores/genética , Transcrição Gênica , Sequência de Bases , Becaplermina , Células Cultivadas , Primers do DNA , Humanos , Fator 4 Semelhante a Kruppel , Músculo Liso Vascular/citologia , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-sis/farmacologia , RNA Mensageiro/genéticaRESUMO
The interleukin 1 receptor-associated kinase 4 (IRAK4) is an essential factor for TLR-mediated activation of the host's immune functions subsequent to pathogen contact. We have characterized the respective cDNA and gene sequences from three salmonid species, salmon, rainbow trout and maraena whitefish. The gene from salmon is structured into eleven exons, as is the mammalian homologue, while exons have been fused in the genes from the two other salmonid species. Rainbow trout expresses also a pseudogene at low levels. Its basic structure resembles more closely the primordial gene than the functional copy does. The N-terminal death domain and the C-terminal protein kinase domain of the factors are better conserved throughout evolution than the linker domain. The deduced amino acid sequences of the factors from all three species group together in an evolutionary tree of IRAK4 factors. Scrutinizing expression and function of IRAK4 from rainbow trout, we found its highest expression in head kidney and spleen and lowest expression in muscle tissue. Infecting fish with Aeromonas salmonicida did not modulate its expression during 72 h of observation. Expression of a GFP-tagged trout IRAK4 revealed, expectedly, its cytoplasmic localization in human HEK-293 cells. However, this factor significantly quenched in a dose-dependent fashion not only the pathogen-induced stimulation of NF-κB factors in the HEK-293 reconstitution system of TLR2 signaling, but also the basal NF-κB levels in unstimulated control cells. Our data unexpectedly imply that IRAK4 is involved in establishing threshold levels of active NF-κB in resting cells.
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Aeromonas salmonicida/imunologia , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Quinases Associadas a Receptores de Interleucina-1/imunologia , Filogenia , Salmonidae , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Doenças dos Peixes/genética , Doenças dos Peixes/imunologia , Rearranjo Gênico/imunologia , Infecções por Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Células HEK293 , Humanos , Quinases Associadas a Receptores de Interleucina-1/genética , Dados de Sequência Molecular , RNA Mensageiro/química , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Alinhamento de Sequência , Análise de Sequência de DNA , Transdução de Sinais/imunologia , Receptores Toll-Like/imunologiaRESUMO
This paper describes comparative studies and protocols in (1) self-assembling of ultrasmall superparamagnetic iron oxide nanoparticle (NP), circular plasmid DNA, and branched polyethylenimine (PEI) composites; (2) magnetofection; (3) gene delivery, (4) magnetic resonance imaging (MRI), and (5) cytotoxicity of the composites toward hepatocellular carcinoma HepG2 cells.
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Nanocompostos/química , Coloração e Rotulagem , Alginatos/química , Animais , Carcinoma Hepatocelular , Sobrevivência Celular , Citratos/química , DNA Circular/química , DNA Circular/genética , Cães , Óxido Ferroso-Férrico/química , Proteínas de Fluorescência Verde/biossíntese , Células Hep G2 , Humanos , Luciferases de Renilla/biossíntese , Células Madin Darby de Rim Canino , Imageamento por Ressonância Magnética , Plasmídeos/química , Plasmídeos/genética , Polietilenoimina/química , TransfecçãoRESUMO
The codon-optimized gene for the mutated 19 kDa protein (nanoKAZ), which is the catalytic component of Oplophorus luciferase, was expressed in Escherichia coli cells and the recombinant protein was highly purified. The secretory expression of nanoKAZ from CHO-K1 cells was performed by fusing the secretory signal peptide sequence of Gaussia luciferase to the amino-terminus of nanoKAZ. The substrate specificity for the purified nanoKAZ and the nanoKAZ secreted into the cultured medium was determined, indicating that bis-coelenterazine (bis-CTZ) and newly synthesized 6h-f-coelenterazine (6h-f-CTZ) are an efficient substrate for the glow luminescence reaction of nanoKAZ.
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Domínio Catalítico , Decápodes/enzimologia , Imidazóis/metabolismo , Luciferases/metabolismo , Luminescência , Proteínas Mutantes/metabolismo , Pirazinas/metabolismo , Sequência de Aminoácidos , Animais , Células CHO , Copépodes , Cricetinae , Cricetulus , Escherichia coli/metabolismo , Imidazóis/química , Luciferases/química , Luciferases/isolamento & purificação , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/isolamento & purificação , Sinais Direcionadores de Proteínas , Pirazinas/química , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Especificidade por SubstratoRESUMO
Mucopolysaccharidosis VII (MPS VII) is due to the deficient activity of ß-glucuronidase (GUSB) and results in the accumulation of glycosaminoglycans (GAGs) in lysosomes and multisystemic disease with cardiovascular manifestations. The goal here was to determine the pathogenesis of mitral valve (MV) disease in MPS VII dogs. Untreated MPS VII dogs had a marked reduction in the histochemical signal for structurally-intact collagen in the MV at 6 months of age, when mitral regurgitation had developed. Electron microscopy demonstrated that collagen fibrils were of normal diameter, but failed to align into large parallel arrays. mRNA analysis demonstrated a modest reduction in the expression of genes that encode collagen or collagen-associated proteins such as the proteoglycan decorin which helps collagen fibrils assemble, and a marked increase for genes that encode proteases such as cathepsins. Indeed, enzyme activity for cathepsin B (CtsB) was 19-fold normal. MPS VII dogs that received neonatal intravenous injection of a gamma retroviral vector had an improved signal for structurally-intact collagen, and reduced CtsB activity relative to that seen in untreated MPS VII dogs. We conclude that MR in untreated MPS VII dogs was likely due to abnormalities in MV collagen structure. This could be due to upregulation of enzymes that degrade collagen or collagen-associated proteins, to the accumulation of GAGs that compete with proteoglycans such as decorin for binding to collagen, or to other causes. Further delineation of the etiology of abnormal collagen structure may lead to treatments that improve biomechanical properties of the MV and other tissues.
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Doenças das Valvas Cardíacas/etiologia , Valva Mitral/patologia , Mucopolissacaridose VII/complicações , Animais , Cordas Tendinosas/metabolismo , Colágeno/metabolismo , Cães , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Feminino , Glicosaminoglicanos/metabolismo , Doenças das Valvas Cardíacas/metabolismo , Masculino , Valva Mitral/metabolismo , Mucopolissacaridose VII/metabolismo , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Transdução de SinaisRESUMO
BACKGROUND: The ideal treatment for upper ureteric calculi is still debatable, particularly for patients with large, impacted ureteric calculi. Retroperitoneal laparoscopic ureterolithotomy (RLU) may be a worthwhile alternative to open surgery. In this study, we retrospectively evaluated our clinical experience associated with RLU performed for impacted upper ureteric calculi (>1.5 cm) help urologists in clinical practice and provide a reference for clinical work. METHODS: A total of 64 cases (38 males; 26 females) with impacted upper ureteric calculi between April 2018 and January 2020 were analyzed retrospectively. The basic information of the included research subjects are as follows: The mean age was 50.8±25.4 years. The largest stone diameter was 1.8±0.3 cm. The mean stone retention time was 42±11 days. The mean degree of hydronephrosis was 2.8±1.2 cm. RESULTS: The mean operative time was 85.4±18.3 minutes. The mean hospital duration was 7.5±1.8 days. The stone-free rate was 98.4%. Two patients required additional intervention. Post-operative fever developed in 3 patients. The decrease in hemoglobin levels was 7.8±3.6 g/L. The increase in procalcitonin (PCT) level was 3.7±1.8 ng/mL. No major complications, for example, sepsis, bleeding, bowel injury, or cardiopulmonary morbidities, were reported. CONCLUSIONS: RLU should be regarded as an excellent first line treatment modality for impacted upper ureteric calculi (>1.5 cm) owing to the high success rate, low complication rate, and the short length of operative time and hospital duration.
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The spread of coronavirus disease 2019 (COVID-19) throughout the world has resulted in stressful healthcare burdens and global health crises. Developing an effective measure to protect people from infection is an urgent need. The blockage of interaction between angiotensin-converting enzyme 2 (ACE2) and S protein is considered an essential target for anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) drugs. A full-length ACE2 protein could be a potential drug to block early entry of SARS-CoV-2 into host cells. In this study, a therapeutic strategy was developed by using extracellular vesicles (EVs) with decoy receptor ACE2 for neutralization of SARS-CoV-2. The EVs embedded with engineered ACE2 (EVs-ACE2) were prepared; the EVs-ACE2 were derived from an engineered cell line with stable ACE2 expression. The potential effect of the EVs-ACE2 on anti-SARS-CoV-2 was demonstrated by both in vitro and in vivo neutralization experiments using the pseudovirus with the S protein (S-pseudovirus). EVs-ACE2 can inhibit the infection of S-pseudovirus in various cells, and importantly, the mice treated with intranasal administration of EVs-ACE2 can suppress the entry of S-pseudovirus into the mucosal epithelium. Therefore, the intranasal EVs-ACE2 could be a preventive medicine to protect from SARS-CoV-2 infection. This EVs-based strategy offers a potential route to COVID-19 drug development.
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OBJECTIVE: Given the limitations of current anti-resorption agents for postmenopausal osteoporosis, there is a need for alternatives without impairing coupling crosstalk between bone resorption and bone formation ie. osteoclastogenesis. Puerarin, a unique C-glycoside isoflavonoid, was found to be able to prevent bone loss by inhibiting bone resorption, but the underlying mechanism was controversial. In this study, we investigated the effects of puerarin on osteoclastic differentiation, activation and bone resorption and its underlying molecular mechanism in vitro, and then evaluated the effects of puerarin on bone metabolism using an ovariectomized (OVX) rat model. METHODS: In vitro, the effect of puerarin on osteoclastic cytotoxicity, differentiation, apoptosis, activation and function were studied in raw 264.7 âcells and mouse BMMs. Mechanistically, osteoclast-related makers were determined by RT-PCR, western blot, immunofluorescence, and kinase activity assay. In vivo, Micro-CT, histology, serum bone biomarker, and mechanical testing were used to evaluate the effects of puerarin on preventing osteoporosis. RESULTS: Puerarin significantly inhibited osteoclast activation and bone resorption, without affecting osteoclastogenesis or apoptosis. In terms of mechanism, the expressions of protein of integrin-ß3 and phosphorylations of Src, Pyk2 and Cbl were lower in puerarin group than those in the control group. Oral administration of puerarin prevented OVX-induced trabecular bone loss and significantly improved bone strength in rats. Moreover, puerarin significantly decreased trap positive osteoclast numbers and serum TRAP-5b, CTx1, without affecting bone formation rate. CONCLUSIONS: Collectively, puerarin prevented the bone loss in OVX rat through suppression of osteoclast activation and bone resorption, by inhibiting integrin-ß3-Pyk2/Cbl/Src signaling pathway, without affecting osteoclasts formation or apoptosis. TRANSLATIONAL POTENTIAL OF THIS ARTICLE: These results demonstrate the unique mechanism of puerarin on bone metabolism and provide a novel agent for prevention of postmenopausal osteoporosis.
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Bitter taste perception is mediated by a family of G protein-coupled receptors (T2Rs) in vertebrates. Common carp (Cyprinus carpio), which has experienced an additional round of whole genome duplication during the course of evolution, has a small number of T2R genes similar to zebrafish, a closely related cyprinid fish species, and their expression pattern at the cellular level or their cognate ligands have not been elucidated yet. Here, we showed through in situ hybridization experiments, that three common carp T2R (ccT2R) genes encoding ccT2R200-1, ccT2R202-1, and ccT2R202-2, were specifically expressed in the subsets of taste receptor cells in the lips and gill rakers. ccT2R200-1 was co-expressed with genes encoding downstream signal transduction molecules, such as PLC-ß2 and Gαia. Heterologous expression system revealed that each ccT2R showed narrowly, intermediately, or broadly tuned ligand specificity, as in the case of zebrafish T2Rs. However, ccT2Rs showed different ligand profiles from their orthologous zebrafish T2Rs previously reported. Finally, we identified three ccT2Rs, namely ccT2R200-1, ccT2R200-2, and ccT2R203-1, to be activated by natural bitter compounds, andrographolide and/or picrotoxinin, which elicited no response to zebrafish T2Rs, in a dose-dependent manner. These results suggest that some ccT2Rs may have evolved to function in the oral cavity as taste receptors for natural bitter compounds found in the habitats in a species-specific manner.
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Coffee brewed from capsule machines may contain estrogenic chemicals migrated from plastic, but the estrogenic activity of capsule coffee has not been evaluated. This study evaluated the estrogenic activity of capsule coffee using the VM7Luc4E2 estrogen receptor transcriptional activation assay. Estrogenic potentials of six capsule coffee samples were calculated using relative maximum amplitude response of E2 (>15%RME2 indicative of estrogenic activity) and estradiol equivalent factor (EEF). Estrogenic chemical content was determined using ultra-performance liquid chromatography with tandem mass spectrometry. All capsule coffee samples possessed estrogenic activity (48-56%RME2). EEFs were 6-7 orders of magnitude lower than that of E2, (1.2 × 10-7-1.7 × 10-6), indicating substantially weaker estrogenic potencies. Bisphenol A, bisphenol F, benzophenone, 4-nonylphenol, dibutyl phthalate, and dimethyl terephthalate were detected in capsule coffee. Capsule coffee exhibited estrogenic activity in vitro, and its estrogenic chemical content is likely driving its estrogenicity, warranting further investigations to fully understand the degree to which they are related and to predict the estrogenic potential based on the concentration of estrogenic chemicals.
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INTRODUCTION: Currently, embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) can be induced to differentiate at the cellular level but not to form mature tissues or organs suitable for transplantation. ESCs/iPSCs form immature teratomas after injection into immunodeficient mice. In humans, immature teratomas often transform into fully differentiated mature teratomas after administration of anticancer agents. METHODS: We first investigated the ability of cisplatin to induce changes in mouse ESCs/iPSCs in vitro. Next, we designed experiments to analyze ESC/iPSC-derived immature teratoma tissue in vivo after treatment of cisplatin. Groups of six mice carrying ESC- or iPSC-derived teratomas were given either low or high dose intraperitoneal injection of cisplatin, while the control group received saline for 4 weeks. RESULTS: Treatment of ESC/iPSC cultures with cisplatin for 3 days caused a dose-related decrease in cell numbers without inducing any morphological changes to the cells. ESC/iPSC-derived teratomas showed lower growth rates with a significantly higher mature components ratio in a concentration dependent manner after cisplatin treatment (P < 0.05); however, immunohistochemical analyses demonstrated a significantly reduced PCNA labelling index and an increase in an apoptosis marker on immature neural components (P < 0.05) along with emergence of h-Caldesmon+ mature smooth muscle cells in treated mice. Moreover, newly differentiated components not found in the control group, such as mature adipose tissue, cartilage, and pancreas, as well as striated muscle, salivary glands, gastric mucosa with fundic glands, and hair follicles emerged. The identities of these components were confirmed by immunostaining for specific markers. CONCLUSIONS: Cisplatin has the ability to reduce immature components in ESC/iPSC-derived teratomas, presumably through apoptosis, and also to induce them to differentiate.
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Introduction: Alzheimer's disease (AD) is a progressive brain disorder, and one of the most common causes of dementia and amnesia. Due to the complex pathogenesis of AD, the underlying mechanisms remain unclear. Although scientists have made increasing efforts to develop drugs for AD, no effective therapeutic agents have been found. Objectives: Natural products and their constituents have shown promise for treating neurodegenerative diseases, including AD. Thus, in-depth study of medical plants, and the main active ingredients thereof against AD, is necessary to devise therapeutic agents. Methods: In this study, N2a/APP cells and SAMP8 mice were employed as in vitro and in vivo models of AD. Multiple molecular biological methods were used to investigate the potential therapeutic actions of oxyphylla A, and the underlying mechanisms. Results: Results showed that oxyphylla A, a novel compound extracted from Alpinia oxyphylla, could reduce the expression levels of amyloid precursor protein (APP) and amyloid beta (Aß) proteins, and attenuate cognitive decline in SAMP8 mice. Further investigation of the underlying mechanisms showed that oxyphylla A exerted an antioxidative effect through the Akt-GSK3ß and Nrf2-Keap1-HO-1 pathways.Conclusions.Taken together, our results suggest a new horizon for the discovery of therapeutic agents for AD.
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Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Animais , Caproatos , Cognição , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Cresóis , Modelos Animais de Doenças , Glicogênio Sintase Quinase 3 beta , Proteína 1 Associada a ECH Semelhante a Kelch , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-aktRESUMO
Histone lysine specific demethylase 1 (LSD1) has become a potential therapeutic target for the treatment of cancer. Discovery and develop novel and potent LSD1 inhibitors is a challenge, although several of them have already entered into clinical trials. Herein, for the first time, we reported the discovery of a series of 5-cyano-6-phenylpyrimidine derivatives as LSD1 inhibitors using flavin adenine dinucleotide (FAD) similarity-based designing strategy, of which compound 14q was finally identified to repress LSD1 with IC50 = 183 nmol/L. Docking analysis suggested that compound 14q fitted well into the FAD-binding pocket. Further mechanism studies showed that compound 14q may inhibit LSD1 activity competitively by occupying the FAD binding sites of LSD1 and inhibit cell migration and invasion by reversing epithelial to mesenchymal transition (EMT). Overall, these findings showed that compound 14q is a suitable candidate for further development of novel FAD similarity-based LSD1 inhibitors.
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The formyl peptide receptor 2 (FPR2) belongs to the family of seven-transmembrane G protein-coupled receptors (GPCR) and are expressed by many different cells but mainly studied in immune cells. FPR2 is involved in host defense against bacterial infections and clearance of damaged cells through the oxidative burst and chemotaxis of neutrophils. In addition, FPR2 has also been implicated as an immunomodulator in sterile inflammations, e.g. inflammatory joint diseases. Here we present data regarding FPR2 expression in human articular chondrocytes, isolated from healthy individuals and osteoarthritic patients, on both mRNA and protein level using qPCR and Imagestream flow cytometry. We also present data after receptor stimulation and monitoring of production of nitric oxide, reactive oxygen species, IL-6, IL-8 and MMP-3. The presented data show that human articular chondrocytes from patients with osteoarthritis as well as from healthy individuals express FPR2 both at mRNA and protein level. The biological relevance of FPR2 expression in chondrocytes needs to be further investigated.
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OBJECTIVES: Competitive immunoenyzmatic assays for estradiol (E2) and unconjugated estriol (uE3) on UniCel DxI 800 Access immunoassay systems (Beckman Coulter) utilize bovine alkaline phosphatase (ALP) for amplification. In these assays, rare 'IND' error flags indicate that a relative light unit (RLU) raw result is past the high or low end of the calibration curve but cannot be differentiated from an instrument error or analytical interference. The present studies were conducted to establish a protocol to identify analytical interference and to characterize its mechanism when present. DESIGN AND METHODS: Matrix and recovery studies were conducted to establish a protocol for interference identification. Spiking experiments with inactivated calf intestinal ALP were performed to determine whether interference could be blocked. Commercial anti-ALP antibodies (Abs) were spiked into human serum to model assay interference. Three E2 immunoassays which do not include ALP as a reagent component (cobas e602, Roche; Centaur XP, Siemens; ARCHITECT i2000SR, Abbott) were tested for comparative purposes. RESULTS: 1:2 dilution of specimen into Access Sample Diluent A (Beckman) differentiated IND error flags due to true low results (e.g. less than the analytical measurement range; AMR) from those due to assay interference. Interferences were reduced by pre-incubation with inactivated ALP and could be replicated by spiking with commercial anti-ALP Abs. CONCLUSIONS: Patient anti-bovine ALP Abs can cause interference on DxI 800 E2 and uE3 assays. This model can be used to investigate interference risk with other ALP-dependent assays.
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OBJECTIVE: To investigate the development of a minimal traditional Chinese medicine (TCM) formula using selected TCM ingredients and evaluating their biological activity with bone-specific in vitro tests. Finally, determining if the minimal formula can maintain bone mineral density (BMD) in a low bone mass (LBM)/osteoporosis (OP) model system. METHODS AND RESULTS: Sixteen different TCM plant extracts were tested for estrogenic, osteogenic and osteoclastic activities. Despite robust activation of the full-length estrogen receptors α and ß by Psoralea corylifolia and Epimedium brevicornu, these extracts do not activate the isolated estrogen ligand binding domains (LBD) of either ERα or ERß; estrogen (17-ß estradiol) fully activates the LBD of ERα and ERß. E. brevicornu and Drynaria fortunei extracts activated cyclic AMP response elements (CRE) individually and when combined these ingredients stimulated the production of osteoblastic markers Runx2 and Bmp4 in MC3T3-E1 cells. E. brevicornu, Salvia miltiorrhiza, and Astragalus onobrychis extracts inhibited the Il-1ß mediated activation of NF-κß and an E. brevicornu/D. fortunei combination inhibited the development of osteoclasts from precursor cells. Further, a minimal formula containing the E. brevicornu/D. fortunei combination with or without a third ingredient (S. miltiorrhiza, Angelica sinensis, or Lycium barbarum) maintained bone mineral density (BMD) similar to an estradiol-treated control group in the ovariectomized rat; a model LBM/OP system. CONCLUSION: A minimal formula consisting of TCM plant extracts that activate CRE and inhibit of NF-κß activation, but do not behave like estrogen, maintain BMD in a LBM/OP model system.
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INTRODUCTION: Biomedical applications of nanoparticles (NPs) as enzyme inhibitors have recently come to light. Oxides of metals native to the physiological environment (eg, Fe, Zn, Mg, etc.) are of particular interest-especially the functional consequences of their enzyme interaction. MATERIALS AND METHODS: Here, Fe2O3, zinc oxide (ZnO), magnesium oxide (MgO) and nickel oxide (NiO) NPs are compared to copper (Cu) and boron carbide (B4C) NPs. The functional impact of NP interaction to the model enzyme luciferase is determined by 2-dimensional fluorescence difference spectroscopy (2-D FDS) and 2-dimensional photoluminescence difference spectroscopy (2-D PLDS). By 2-D FDS analysis, the change in maximal intensity and in 2-D FDS area under the curve (AUC) is in the order Cu~B4C>ZnO>NiO>>Fe2O3>MgO. The induced changes in protein conformation are confirmed by tryptic digests and gel electrophoresis. RESULTS: Analysis of possible trypsin cleavage sites suggest that cleavage mostly occurs in the range of residues 112-155 and 372-439, giving a major 45 kDa band. By 2-D PLDS, it is found that B4C NPs completely ablate bioluminescence, while Cu and Fe2O3 NPs yield a unique bimodal negative decay rate, -7.67×103 and -3.50×101 relative light units respectively. Cu NPs, in particular, give a remarkable 271% change in enzyme activity. Molecular dynamics simulations in water predicted that the surfaces of metal oxide NPs become capped with metal hydroxide groups under physiological conditions, while the surface of B4C becomes populated with boronic acid or borinic acid groups. These predictions are supported by the experimentally determined zeta potential. Thin layer chromatography patterns further support this conception of the NP surfaces, where stabilizing interactions were in the order ionic>polar>non-polar for the series tested. CONCLUSION: Overall the results suggest that B4C and Cu NP functional dynamics on enzyme biochemistry are unique and should be examined further for potential ramifications on other model, physiological or disease-relevant enzymes.