A rapid and efficient one-pot three-component synthesis of 2-amino-3-cyano-4-aryl-7-methyl-5-oxo-4,5-dihydro-pyrano-[3,2-c]pyran and 2-amino-3-cyano-4-aryl-6-methyl5,6-dihydro-5-oxo-4H-pyrano-[3,2-c]quinoline derivati...
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A rapid and efficient one-pot three-component synthesis of 2-amino-3-cyano-4-aryl-7-methyl-5-oxo-4,5-dihydro-pyrano-[3,2-c]pyran and 2-amino-3-cyano-4-aryl-6-methyl5,6-dihydro-5-oxo-4H-pyrano-[3,2-c]quinoline derivatives catalyzed by copper nanoparticles grafted on carbon microspheres is developed. The use of heterogeneous catalyst, mild reaction conditions, and excellent yield of the corresponding products are the key features of the present protocol.
Background Tumor cells exhibited phenotypic and molecular characteristics similar to their lineage progenitor cells. Liver developmental signaling pathways are showed to be associated with Hcc development and oncogene...
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Background Tumor cells exhibited phenotypic and molecular characteristics similar to their lineage progenitor cells. Liver developmental signaling pathways are showed to be associated with Hcc development and oncogenesis. The similarities of expression profiling between liver progenitors (LPs) and Hcc suggest that understanding the molecular mechanism during liver development could provide insights into Hcc. Methods To profile the dynamic gene expression during liver development, cells from an in vitro liver differentiation model and two paired hepatocellular carcinoma (Hcc) samples were analyzed using deep RNA sequencing. The expression levels of selected genes were analyzed by qRT-PcR. Moreover, the role of a key transcription factor, pituitary homeobox 2 (PITX2), was characterized via in vitro and vivo functional assays. Furthermore, molecular mechanism studies were performed to unveil how PITX2c regulate the key developmental factors in LPs, thereby increasing the stemness of Hcc. Results PITX2 was found to exhibit a similar expression pattern to specific markers of LPs. PITX2 consists of three isoforms (PITX2A/B/c). The expression of PITX2 is associated with tumor size and overall survival rate, whereas only PITX2c expression is associated with AFP and differentiation in clinical patients. PITX2A/B/c has distinct functions in Hcc tumorigenicity. PITX2c promotes Hcc metastasis, self-renewal and chemoresistance. Molecular mechanism studies showed that PITX2ccould up-regulate RALYL which could enhance Hcc stemness via the TGF-beta pathway. Furthermore, chIP assays confirmed the role of PITX2c in regulating key developmental factors in LP. conclusion PITX2c is a newly discovered transcription factor involved in hepatic differentiation and could increase Hcc stemness by upregulating key transcriptional factors related to liver development.
Two new seco-prezizaane-type sesquiterpenes, 2 beta-hydroxy-6-deoxyneoanisatin (1) and 3,4-anhydro-2-oxo-1 alpha-hydroxy-6-deoxyneoanisatin (2), and two new prenylated c-6-c-3 compounds, illilanceofunones A (3) and B ...
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Two new seco-prezizaane-type sesquiterpenes, 2 beta-hydroxy-6-deoxyneoanisatin (1) and 3,4-anhydro-2-oxo-1 alpha-hydroxy-6-deoxyneoanisatin (2), and two new prenylated c-6-c-3 compounds, illilanceofunones A (3) and B (4), were obtained from the fruits of Illicium lanceolatum, along with four known prenylated c-6-c-3 compounds (5-8). Their structures were proposed through HR-ESI-MS, H-1, c-13, and 2D NMR data interpretation. Moreover, the absolute configuration of 1 and 2 were further assigned by single-crystal X-ray diffraction analysis and electroniccircular dichroism (EcD) calculations, respectively. Illihenryipyranol A (6) exhibited neuroprotective activity against MPP+-induced Pc12 cell damage in a dose-dependent manner.
Physiological stress triggers aversive learning that profoundly alters animal behavior. Systemic mitochondrial disruption induces avoidance of c. elegans to non-pathogenic food bacteria. Mutations in cat-2 and dat-1, ...
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Physiological stress triggers aversive learning that profoundly alters animal behavior. Systemic mitochondrial disruption induces avoidance of c. elegans to non-pathogenic food bacteria. Mutations in cat-2 and dat-1, which control dopamine synthesis and reuptake, respectively, impair this learned bacterial avoidance, suggesting that dopaminergic modulation is essential. cell-specific rescue experiments indicate that dopamine likely acts from the cEP and ADE neurons to regulate learned bacterial avoidance. We find that mutations in multiple dopamine receptor genes, including dop-1, dop-2 and dop-3, reduced learned bacterial avoidance. Our work reveals a role for dopamine signaling in c. elegans learned avoidance behavior induced by mitochondrial stress.
Hepatocellular carcinoma (Hcc) is a highly malignant tumor and its progression is associated with altered lipid metabolism in precancerous lesions, such as non-alcoholic fatty liver disease. Here, we identified sperm ...
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Hepatocellular carcinoma (Hcc) is a highly malignant tumor and its progression is associated with altered lipid metabolism in precancerous lesions, such as non-alcoholic fatty liver disease. Here, we identified sperm associated antigen 4 (SPAG4), and explored its oncogenic role in Hcc progression. Database analysis and immunohistochemistry indicated increased level of SPAG4 in Hcc tissues which was of prognostic value. Gain/loss-offunction experiments showed that SPAG4 exerted oncogenic roles in Hcc growth both in vitro and in vivo. RNA sequencing revealed activation of a lipogenic state and SREBP1-mediated pathway following SPAG4 overexpression. Mechanistically, the N-terminal region of SPAG4 bound to lamin A/c, which increased SREBP1 expression, nuclear translocation, and transcriptional activity. Treatment with orlistat, a lipid synthesis inhibitor, reversed SPAG4-mediated oncogenic effects, and its efficacy varied with SPAG4 level. The effect of orlistat was further amplified when combined with sorafenib in tumor xenograft mouse models. Our study provides evidence that SPAG4 mediates Hcc progression by affecting lipid metabolism. Administration of orlistat combined with sorafenib reverses SPAG4-mediated oncogenesis in Hcccells and ectopic xenograft tumors in mice, suggesting that this pathway represents a potential target for Hcc treatment.
Allergiccontact dermatitis (AcD) is a prevalent and poorly controlled inflammatory disease caused by skin infiltration of T cells and granulocytes. The beta common (beta(c)) cytokines GM-cSF, IL-3, and IL-5 are power...
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Allergiccontact dermatitis (AcD) is a prevalent and poorly controlled inflammatory disease caused by skin infiltration of T cells and granulocytes. The beta common (beta(c)) cytokines GM-cSF, IL-3, and IL-5 are powerful regulators of granulocyte function that signal through their common receptor subunit beta(c), a property that has made beta(c) an attractive target to simultaneously inhibit these cytokines. However, the species specificity of beta(c) has precluded testing of inhibitors of human beta(c) in mouse models. To overcome this problem, we developed a human beta(c) receptor transgenic mouse strain with a hematopoieticcell-specific expression of human beta(c) instead of mouse beta(c). Human beta(c) receptor transgeniccells responded to mouse GM-cSF and IL-5 but not to IL-3 in vitro and developed tissue pathology and cellular inflammation comparable with those in wild-type mice in a model of AcD. Similarly, Il3(-/-) mice developed AcD pathology comparable with that of wild-type mice. Importantly, the blocking anti-human beta(c) antibody cSL311 strongly suppressed ear pinna thickening and histopathological changes typical of AcD and reduced accumulation of neutrophils, mast cells, and eosinophils in the skin. These results show that GM-cSF and IL-5 but not IL-3 are major mediators of AcD and define the human beta(c) receptor transgenic mouse as a unique platform to test the inhibitors of beta(c) in vivo.
Background As a fatal interstitial lung disease, idiopathic pulmonary fibrosis (IPF) was characterized by the insidious proliferation of extracellular matrix (EcM)-producing mesenchymal cells. Recent studies have demo...
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Background As a fatal interstitial lung disease, idiopathic pulmonary fibrosis (IPF) was characterized by the insidious proliferation of extracellular matrix (EcM)-producing mesenchymal cells. Recent studies have demonstrated that lung resident mesenchymal/stromal cells (LR-MSc) are the source of myofibroblasts. Endoplasmic reticulum (ER) stress is prominent in IPF lung. This study sought to investigate the effects of ER stress on the behavior of LR-MSc during pulmonary fibrosis. Methods ER stress and myofibroblast differentiation of LR-MSc in patients with IPF were evaluated. Primary mouse LR-MSc was harvested and used in vitro for testing the effects of ER stress and c/EBP homologous protein (cHOP) on LR-MSc. Adoptive transplantation of LR-MSc to bleomycin-induced pulmonary fibrosis was done to test the in vivo behavior of LR-MSc and its influence on pulmonary fibrosis. Results We found that myofibroblast differentiation of LR-MSc is associated with ER stress in IPF and bleomycin-induced mouse fibrotic lung. Tunicamycin-induced ER stress impairs the paracrine, migration, and reparative function of mouse LR-MSc to injured type 2 alveolar epithelial cells MLE-12. Overexpression of the ER stress responder c/EBP homologous protein (cHOP) facilitates the TGF beta 1-induced myofibroblast transformation of LR-MSc via boosting the TGF beta/SMAD signaling pathway. cHOP knockdown facilitates engraftment and inhibits the myofibroblast transformation of LR-MSc during bleomycin-induced pulmonary fibrosis, thus promoting the efficacy of adopted LR-MSc in alleviating pulmonary fibrosis. conclusion Our work revealed a novel role that ER stress involved in pulmonary fibrosis by influencing the fate of LR-MSc and transformed to "crime factor" myofibroblast, during which cHOP acts as the key modulator. These results indicate that pharmacies targeting cHOP or therapies based on cHOP knockdown LR-MSc may be promising ways to treat pulmonary fibrosis.
caenorhabditis elegans is a well-established model organism for toxicity testing of chemical substances. We recently demonstrated its potential for bioanalysis of the toxic potency of chemical contaminants in water. W...
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caenorhabditis elegans is a well-established model organism for toxicity testing of chemical substances. We recently demonstrated its potential for bioanalysis of the toxic potency of chemical contaminants in water. While many detoxification genes are homologues to those in mammalians, c. elegans is reported to be deficient in cytochrome cYP1-like P450 metabolism and that its aryl hydrocarbon receptor (AhR) homolog encoded by ahr-1 purportedly does not interact with dioxins or any other known xenobiotic ligand. This suggests that c. elegans is insensitive for compounds that require bioactivation (indirectly acting compounds) and for dioxins or dioxin-like compounds. This study analysed genome-wide gene expression of the nematode in response to 30 mu M of aflatoxin B1 (AFB1), benzo(a)pyrene (B(a)P), Aroclor 1254 (PcB1254), and 10 mu M of 2,3,7,8-tetrachlorodibenzodioxin (TcDD). After 24 h of exposure in the early L4 larval stage, microarray analysis revealed 182, 86, and 321 differentially expressed genes in the nematodes treated with 30 mu M of AFB1, B(a)P, and PcB1254, respectively. Among these genes, many encode xenobiotic-metabolizing enzymes, and their transcription levels were among the highest-ranked fold-changed genes. Interestingly, only one gene (F59B1.8) was upregulated in the nematodes exposed to 10 mu M TcDD. Genes related to metabolic processes and catalytic activity were the most induced by exposure to 30 mu M of AFB1, B(a)P, and PcB1254. Despite the genotoxic nature of AFB1 and B(a)P, no differential expression was found in the genes encoding DNA repair and cell cycle checkpoint proteins. Analysis of con-centration-response curves was performed to determine the Lowest Observed Transcriptomic Effect Levels (LOTEL) of AFB1, B(a)P, and PcB1254. The obtained LOTEL values showed that gene expression changes in c. elegans are more sensitive to toxicants than reproductive effects. Overall, transcriptional responses of meta-bolic enzymes suggest that the nema
Purpose In women under the age of 40, primary ovarian insufficiency (POI) is a devastating diagnosis with significant prevalence of 1-4% (Rajkovic and Pangas, Semin Reprod Med. 35(3):231-40, 2017). POI is characterize...
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Purpose In women under the age of 40, primary ovarian insufficiency (POI) is a devastating diagnosis with significant prevalence of 1-4% (Rajkovic and Pangas, Semin Reprod Med. 35(3):231-40, 2017). POI is characterized by amenorrhea with elevated levels of follicle stimulating hormone (FSH) and reduced estrogen levels, mimicking the menopausal state. Genetic determinants account for just over 10% of POI cases, yet determining whether particular single nucleotide polymorphisms (SNPs) are pathogenic is challenging. Methods We performed exome sequencing on a cohort of women with POI. cRISPR mutagenesis was employed to create a mutation in a conserved amino acid in the nematode protein. Functional relevance was assessed by analysis of bivalents and aberrant DNA morphologies in diakinesis nuclei. Results We identified a nonsynonymous c.c1051G;p.R351G variant, in a conserved region of the MSH5 protein. Mutation of this conserved amino acid in the c. elegans homolog, msh-5, revealed defective crossover outcomes in the homozygous and hemizygous states. conclusions These studies further implicate MSH5 as a POI gene and c.c1051G;p.R351G variant as likely playing a functional role in mammalian meiosis. This approach also highlights the ability of model organisms, such as c. elegans, to rapidly and inexpensively identify alleles of interest for further studies in mammalian models.
Riboflavin (Rf), or vitamin B2, is the precursor of FMN and FAD, redox cofactors of several dehydrogenases involved in energy metabolism, redox balance and other cell regulatory processes. FAD synthase, coded by FLAD1...
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Riboflavin (Rf), or vitamin B2, is the precursor of FMN and FAD, redox cofactors of several dehydrogenases involved in energy metabolism, redox balance and other cell regulatory processes. FAD synthase, coded by FLAD1 gene in humans, is the last enzyme in the pathway converting Rf into FAD. Mutations in FLAD1 gene are responsible for neuromuscular disorders, in some cases treatable with Rf. In order to mimic these disorders, the caenorhabditis elegans (c. elegans) gene orthologue of FLAD1 (flad-1) was silenced in a model strain hypersensitive to RNA interference in nervous system. Silencing flad-1 resulted in a significant decrease in total flavin content, paralleled by a decrease in the level of the FAD-dependent ETFDH protein and by a secondary transcriptional down-regulation of the Rf transporter 1 (rft-1) possibly responsible for the total flavin content decrease. conversely an increased ETFDH mRNA content was found. These biochemical changes were accompanied by significant phenotypical changes, including impairments of fertility and locomotion due to altered cholinergic transmission, as indicated by the increased sensitivity to aldicarb. A proposal is made that neuronal acetylcholine production/release is affected by alteration of Rf homeostasis. Rf supplementation restored flavin content, increased rft-1 transcript levels and eliminated locomotion defects. In this aspect, c. elegans could provide a low-cost animal model to elucidate the molecular rationale for Rf therapy in human Rf responsive neuromuscular disorders and to screen other molecules with therapeutic potential.
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