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Metabolic inflammation is closely linked to obesity, and is implicated in the pathogenesis of metabolic diseases. FTO harbors the strongest genetic association with polygenic obesity, and IRX3 mediates the effects of FTO on body weight. However, in what cells and how IRX3 carries out this control are poorly understood. Here we report that macrophage IRX3 promotes metabolic inflammation to accelerate the development of obesity and type 2 diabetes. Mice with myeloid-specific deletion of Irx3 were protected against diet-induced obesity and metabolic diseases via increasing adaptive thermogenesis. Mechanistically, macrophage IRX3 promoted proinflammatory cytokine transcription and thus repressed adipocyte adrenergic signaling, thereby inhibiting lipolysis and thermogenesis. JNK1/2 phosphorylated IRX3, leading to its dimerization and nuclear translocation for transcription. Further, lipopolysaccharide stimulation stabilized IRX3 by inhibiting its ubiquitination, which amplified the transcriptional capacity of IRX3. Together, our findings identify a new player, macrophage IRX3, in the control of body weight and metabolic inflammation, implicating IRX3 as a therapeutic target.
Assuntos
Proteínas de Homeodomínio/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Obesidade/metabolismo , Fatores de Transcrição/metabolismo , Adipócitos/metabolismo , Adulto , Animais , Peso Corporal/fisiologia , Linhagem Celular , Diabetes Mellitus Tipo 2/metabolismo , Dieta/métodos , Células HEK293 , Humanos , Masculino , Doenças Metabólicas/metabolismo , Camundongos , Células RAW 264.7 , Células THP-1 , Termogênese/fisiologia , Transcrição Gênica/fisiologia , Adulto JovemRESUMO
Accumulation of senescent cells in organs and tissues is a hallmark of aging and known to contribute to age-related diseases. Although aging-associated immune dysfunction, or immunosenescence, is known to contribute to this process, the underlying mechanism remains elusive. Here, we report that type 2 cytokine signaling deficiency accelerated aging and, conversely, that the interleukin-4 (IL-4)-STAT6 pathway protected macrophages from senescence. Mechanistically, activated STAT6 promoted the expression of genes involved in DNA repair both via homologous recombination and Fanconi anemia pathways. Conversely, STAT6 deficiency induced release of nuclear DNA into the cytoplasm to promote tissue inflammation and organismal aging. Importantly, we demonstrate that IL-4 treatment prevented macrophage senescence and improved the health span of aged mice to an extent comparable to senolytic treatment, with further additive effects when combined. Together, our findings support that type 2 cytokine signaling protects macrophages from immunosenescence and thus hold therapeutic potential for improving healthy aging.
Assuntos
Senescência Celular , Interleucina-4 , Animais , Camundongos , Interleucina-4/metabolismo , Envelhecimento/genética , Macrófagos , InflamaçãoRESUMO
Mutations or aberrant upregulation of EZH2 occur frequently in human cancers, yet clinical benefits of EZH2 inhibitor (EZH2i) remain unsatisfactory and limited to certain hematological malignancies. We profile global posttranslational histone modification changes across a large panel of cancer cell lines with various sensitivities to EZH2i. We report here oncogenic transcriptional reprogramming mediated by MLL1's interaction with the p300/CBP complex, which directs H3K27me loss to reciprocal H3K27ac gain and restricts EZH2i response. Concurrent inhibition of H3K27me and H3K27ac results in transcriptional repression and MAPK pathway dependency in cancer subsets. In preclinical models encompassing a broad spectrum of EZH2-aberrant solid tumors, a combination of EZH2 and BRD4 inhibitors, or a triple-combination including MAPK inhibition display robust efficacy with very tolerable toxicity. Our results suggest an attractive precision treatment strategy for EZH2-aberrant tumors on the basis of tumor-intrinsic MLL1 expression and concurrent inhibition of epigenetic crosstalk and feedback MAPK activation.
Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Histona-Lisina N-Metiltransferase/fisiologia , Proteína de Leucina Linfoide-Mieloide/fisiologia , Animais , Carcinogênese/genética , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Epigênese Genética/genética , Epigenômica/métodos , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Código das Histonas/efeitos dos fármacos , Código das Histonas/genética , Histona-Lisina N-Metiltransferase/genética , Histonas/genética , Histonas/fisiologia , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos SCID , Mutação , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/fisiologia , Complexo Repressor Polycomb 2/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/fisiologia , Ativação Transcricional , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Fatores de Transcrição de p300-CBP/fisiologiaRESUMO
Nitric oxide (NO) regulates diverse cellular signaling through S-nitrosylation of specific Cys residues of target proteins. The intracellular level of S-nitrosoglutathione (GSNO), a major bioactive NO species, is regulated by GSNO reductase (GSNOR), a highly conserved master regulator of NO signaling. However, little is known about how the activity of GSNOR is regulated. Here, we show that S-nitrosylation induces selective autophagy of Arabidopsis GSNOR1 during hypoxia responses. S-nitrosylation of GSNOR1 at Cys-10 induces conformational changes, exposing its AUTOPHAGY-RELATED8 (ATG8)-interacting motif (AIM) accessible by autophagy machinery. Upon binding by ATG8, GSNOR1 is recruited into the autophagosome and degraded in an AIM-dependent manner. Physiologically, the S-nitrosylation-induced selective autophagy of GSNOR1 is relevant to hypoxia responses. Our discovery reveals a unique mechanism by which S-nitrosylation mediates selective autophagy of GSNOR1, thereby establishing a molecular link between NO signaling and autophagy.
Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Autofagia , Glutationa Redutase/metabolismo , Óxido Nítrico/metabolismo , Transdução de Sinais , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Família da Proteína 8 Relacionada à Autofagia/genética , Família da Proteína 8 Relacionada à Autofagia/metabolismo , Hipóxia Celular , Glutationa Redutase/genéticaRESUMO
Embryogenesis is highly dependent on maternally loaded materials, particularly those used for energy production. Different environmental conditions and genetic backgrounds shape embryogenesis. The robustness of embryogenesis in response to extrinsic and intrinsic changes remains incompletely understood. By analyzing the levels of two major nutrients, glycogen and neutral lipids, we discovered stage-dependent usage of these two nutrients along with mitochondrial morphology changes during Caenorhabditis elegans embryogenesis. ATGL, the rate-limiting lipase in cellular lipolysis, is expressed and required in the hypodermis to regulate mitochondrial function and support embryogenesis. The embryonic lethality of atgl-1 mutants can be suppressed by reducing sinh-1/age-1-akt signaling, likely through modulating glucose metabolism to maintain sustainable glucose consumption. The embryonic lethality of atgl-1(xd314) is also affected by parental nutrition. Parental glucose and oleic acid supplements promote glycogen storage in atgl-1(xd314) embryos to compensate for the impaired lipolysis. The rescue by parental vitamin B12 supplement is likely through enhancing mitochondrial function in atgl-1 mutants. These findings reveal that metabolic plasticity contributes to the robustness of C. elegans embryogenesis.
Assuntos
Caenorhabditis elegans , Lipólise , Animais , Caenorhabditis elegans/metabolismo , Lipólise/genética , Lipase/genética , Glucose/metabolismo , Glicogênio/metabolismoRESUMO
Substituting the low-value oxygen evolution reaction (OER) with thermodynamically more favored organic oxidation such as furfural oxidation reaction (FOR) is regarded as a perspective approach to decrease energy cost of hydrogen evolution from water splitting. However, the kinetic of FOR can be even more sluggish than OER under large current density. In this work, a strategy is proposed to accelerate FOR by enhancing the adsorption of oxygenates on active sites. Over the prepared NiMoP/NF anode, only 1.46 V versus RHE is required in furfural solution to achieve 500 mA cm-2 , significantly better than the OER activity over commercial RuO2 /NF under the same current density (1.57 V vs RHE).
RESUMO
The size of lipid droplets varies greatly in vivo and is determined by both intrinsic and extrinsic factors. From an RNAi screen in Drosophila, we found that knocking down subunits of COP9 signalosome (CSN) results in enlarged lipid droplets under high-fat, but not normal, conditions. We identified CG2064, a retinol dehydrogenase (RDH) homolog, as the proteasomal degradation target of CSN in regulating lipid droplet size. RDH/CG2064 interacts with the lipid droplet-resident protein Plin2 and the RDH/CG2064-Plin2 axis acts to reduce the overall level and lipid droplet localization of Bmm/ATGL lipase. This axis is important for larval survival under prolonged starvation. Thus, we discovered an RDH-Plin2 axis modulates lipid droplet size.
Assuntos
Drosophila , Lipase , Gotículas Lipídicas , Perilipina-2 , Animais , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Larva/genética , Larva/metabolismo , Lipase/genética , Lipase/metabolismo , Gotículas Lipídicas/metabolismo , Perilipina-2/metabolismoRESUMO
Chelator-assisted phytoremediation is an efficacious method for promoting the removal efficiency of heavy metals (HMs). The effects of N, N-bis(carboxymethyl)-L-glutamic acid (GLDA) and polyaspartic acid (PASP) on Cd uptake and pyrene removal by Solanum nigrum L. (S. nigrum) were compared in this study. Using GLDA or PASP, the removal efficiency of pyrene was over 98%. And PASP observably raised the accumulation and transport of Cd by S. nigrum compared with GLDA. Meanwhile, both GLDA and PASP markedly increased soil dehydrogenase activities (DHA) and microbial activities. DHA and microbial activities in the PASP treatment group were 1.05 and 1.06 folds of those in the GLDA treatment group, respectively. Transcriptome analysis revealed that 1206 and 1684 differentially expressed genes (DEGs) were recognized in the GLDA treatment group and PASP treatment group, respectively. Most of the DEGs found in the PASP treatment group were involved in the metabolism of carbohydrates, the biosynthesis of brassinosteroid and flavonoid, and they were up-regulated. The DEGs related to Cd transport were screened, and ABCG3, ABCC4, ABCG9 and Nramp5 were found to be relevant with the reduction of Cd stress in S. nigrum by PASP. Furthermore, with PASP treated, transcription factors (TFs) related to HMs such as WRKY, bHLH, AP2/ERF, MYB were down-regulated, while more MYB and bZIP TFs were up-regulated. These TFs associated with plant stress resistance would work together to induce oxidative stress. The above results indicated that PASP was more conducive for phytoremediation of Cd-pyrene co-contaminated soil than GLDA.
Assuntos
Biodegradação Ambiental , Cádmio , Pirenos , Poluentes do Solo , Cádmio/metabolismo , Poluentes do Solo/metabolismo , Pirenos/metabolismo , Solo/química , Peptídeos/metabolismo , Perfilação da Expressão Gênica , Ácido Glutâmico/metabolismoRESUMO
BACKGROUND: C2H2 zinc finger proteins (C2H2-ZFPs), one of the largest transcription factors, play a variety of roles in plant development and growth as well as stress response. While, the evolutionary history and expression profile of the C2H2-ZFP genes in Larix kaempferi (LkZFPs) have not been reported so far. RESULTS: In this study, the whole genome of the LkZFPs was identified and characterized, including physicochemical properties, phylogenetic relationships, conservative motifs, the promoter cis-elements and Gene Ontology (GO) annotation. We identified 47 LkZFPs and divided them into four subfamilies based on phylogenetic analysis and conserved motifs. Subcellular localization prediction showed that most of the LkZFPs were located in the nucleus. Promoter cis-element analysis suggested that the LkZFPs may be involved in the regulation of stress responses. Moreover, Real-time quantitative PCR (RT-qPCR) results showed that Q-type LkZFP genes were involved in the response to abiotic stress, such as salt, drought and hormone stresses. Subcellular localization results showed that LkZFP7 and LkZFP37 were located in the nucleus, LkZFP32 was located in both cytoplasm and nucleus. CONCLUSION: The identification and functional analysis of LkZFPs suggested that some LkZFP genes might play important roles in coping with both biological and abiotic stresses. These results could further increase understanding of the function of the LkZFPs, and provide some research direction and theoretical support.
Assuntos
Dedos de Zinco CYS2-HIS2 , Larix , Dedos de Zinco CYS2-HIS2/genética , Estudo de Associação Genômica Ampla , Larix/genética , Larix/metabolismo , Filogenia , Regiões Promotoras Genéticas , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismoRESUMO
BACKGROUND: With the development of cancer precision medicine, a huge amount of high-dimensional cancer information has rapidly accumulated regarding gene alterations, diseases, therapeutic interventions and various annotations. The information is highly fragmented across multiple different sources, making it highly challenging to effectively utilize and exchange the information. Therefore, it is essential to create a resource platform containing well-aggregated, carefully mined, and easily accessible data for effective knowledge sharing. METHODS: In this study, we have developed "Consensus Cancer Core" (Tri©DB), a new integrative cancer precision medicine knowledgebase and reporting system by mining and harmonizing multifaceted cancer data sources, and presenting them in a centralized platform with enhanced functionalities for accessibility, annotation and analysis. RESULTS: The knowledgebase provides the currently most comprehensive information on cancer precision medicine covering more than 40 annotation entities, many of which are novel and have never been explored previously. Tri©DB offers several unique features: (i) harmonizing the cancer-related information from more than 30 data sources into one integrative platform for easy access; (ii) utilizing a variety of data analysis and graphical tools for enhanced user interaction with the high-dimensional data; (iii) containing a newly developed reporting system for automated annotation and therapy matching for external patient genomic data. Benchmark test indicated that Tri©DB is able to annotate 46% more treatments than two officially recognized resources, oncoKB and MCG. Tri©DB was further shown to have achieved 94.9% concordance with administered treatments in a real clinical trial. CONCLUSIONS: The novel features and rich functionalities of the new platform will facilitate full access to cancer precision medicine data in one single platform and accommodate the needs of a broad range of researchers not only in translational medicine, but also in basic biomedical research. We believe that it will help to promote knowledge sharing in cancer precision medicine. Tri©DB is freely available at www.biomeddb.org , and is hosted on a cutting-edge technology architecture supporting all major browsers and mobile handsets.
Assuntos
Neoplasias , Medicina de Precisão , Humanos , Medicina de Precisão/métodos , Genômica/métodos , Neoplasias/genética , Neoplasias/terapia , Bases de ConhecimentoRESUMO
To control the ongoing COVID-19 pandemic, a variety of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines have been developed. However, the rapid mutations of SARS-CoV-2 spike (S) protein may reduce the protective efficacy of the existing vaccines which is mainly determined by the level of neutralizing antibodies targeting S. In this study, we screened prevalent S mutations and constructed 124 pseudotyped lentiviral particles carrying these mutants. We challenged these pseudoviruses with sera vaccinated by Sinovac CoronaVac and ZF2001 vaccines, two popular vaccines designed for the initial strain of SARS-CoV-2, and then systematically assessed the susceptivity of these SARS-CoV-2 variants to the immune sera of vaccines. As a result, 14 S mutants (H146Y, V320I + S477N, V382L, K444R, L455F + S477N, L452M + F486L, F486L, Y508H, P521R, A626S, S477N + S698L, A701V, S477N + T778I, E1144Q) were found to be significantly resistant to neutralization, indicating reduced protective efficacy of the vaccines against these SARS-CoV-2 variants. In addition, F486L and Y508H significantly enhanced the utilization of human angiotensin-converting enzyme 2, suggesting a potentially elevated infectivity of these two mutants. In conclusion, our results show that some prevalent S mutations of SARS-CoV-2 reduced the protective efficacy of current vaccines and enhance the infectivity of the virus, indicating the necessity of vaccine renewal and providing direction for the development of new vaccines.
Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , Anticorpos Antivirais , Testes de Neutralização , Glicoproteína da Espícula de Coronavírus , Internalização do Vírus , Pandemias , Anticorpos Neutralizantes , MutaçãoRESUMO
Protein arginine methyltransferase 5 (PRMT5) is a promising target for the treatment of malignant tumors. The discovery of nucleoside-derived inhibitors against PRMT5 with novel scaffold has been challenging. Herein, we report our effort on the design and synthesis of nucleoside derivatives bearing sulfonamide scaffold as potent PRMT5 inhibitors. The representative compound 23n was identified as a potent and selective PRMT5 inhibitor with an IC50 value of 8 nM. Molecular docking study demonstrated the binding mode of compound 23n and illustrated its inhibitory activity to PRMT5. The Trimethyl Lock prodrug strategy was used to afford prodrug 36 with lower polarity which could rapidly release the active compound 23n after entering the tumor cells. Cell-based assays revealed that the prodrug 36 restrained the proliferation of Z-138 and MOLM-13 cells and suppressed methylation of PRMT5 substrate more potently than 23n. Additionally, both compound 23n and 36 exerted antiproliferative effects against Z-138 cells mainly by inducing apoptosis effectively rather than arresting cell cycle. Thus, compounds 23n and 36 represent a series of potent PRMT5 inhibitor with novel scaffold.
Assuntos
Nucleosídeos , Pró-Fármacos , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Sulfonamidas/farmacologia , Inibidores Enzimáticos/farmacologia , SulfanilamidaRESUMO
ER stress occurs in many physiological and pathological conditions. However, how chronic ER stress is alleviated in specific cells in an intact organism is an outstanding question. Here, overexpressing the gap junction protein UNC-9 (Uncoordinated) in C. elegans neurons triggers the Ire1-Xbp1-mediated stress response in an age-dependent and cell-autonomous manner. The p38 MAPK PMK-3 regulates the chronic stress through IRE-1 phosphorylation. Overexpressing gap junction protein also activates autophagy. The insulin pathway functions through autophagy, but not the transcription of genes encoding ER chaperones, to counteract the p38-Ire1-Xbp1-mediated stress response. Together, these results reveal an intricate cellular regulatory network in response to chronic stress in a subset of cells in multicellular organism.
Assuntos
Autofagia/fisiologia , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/citologia , Estresse do Retículo Endoplasmático/fisiologia , Insulina/metabolismo , Neurônios/metabolismo , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Estresse Fisiológico , Resposta a Proteínas não Dobradas/fisiologiaRESUMO
NF-YB, a subfamily of Nuclear Factor Y (NF-Y) transcription factor, play crucial role in many biological processes of plant growth and development and abiotic stress responses, and they can therefore be good candidate factors for breeding stress-resistant plants. However, the NF-YB proteins have not yet been explored in Larix kaempferi, a tree species with high economic and ecological values in northeast China and other regions, limiting the breeding of anti-stress L. kaempferi. In order to explore the roles of NF-YB transcription factors in L. kaempferi, we identified 20 LkNF-YB family genes from L. kaempferi full-length transcriptome data and carried out preliminary characterization of them through series of analyses on their phylogenetic relationships, conserved motif structure, subcellular localization prediction, GO annotation, promoter cis-acting elements as well as expression profiles under treatment of phytohormones (ABA, SA, MeJA) and abiotic stresses (salt and drought). The LkNF-YB genes were classified into three clades through phylogenetic analysis and belong to non-LEC1 type NF-YB transcription factors. They have 10 conserved motifs; all genes contain a common motif, and their promoters have various phytohormones and abiotic stress related cis-acting elements. Quantitative real time reverse transcription PCR (RT-qPCR) analysis showed that the sensitivity of the LkNF-YB genes to drought and salt stresses was higher in leaves than roots. The sensitivity of LKNF-YB genes to ABA, MeJA, SA stresses was much lower than that to abiotic stress. Among the LkNF-YBs, LkNF-YB3 showed the strongest responses to drought and ABA treatments. Further protein interaction prediction analysis for LkNF-YB3 revealed that LkNF-YB3 interacts with various factors associated with stress responses and epigenetic regulation as well as NF-YA/NF-YC factors. Taken together, these results unveiled novel L. kaempferi NF-YB family genes and their characteristics, providing the basic knowledge for further in-depth studies on their roles in abiotic stress responses of L. kaempferi.
Assuntos
Larix , Larix/genética , Larix/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Filogenia , Epigênese Genética , Melhoramento Vegetal , Estresse Fisiológico/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Hormônios , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Seipin, the gene that causes Berardinelli-Seip congenital lipodystrophy type 2 (BSCL2), is important for adipocyte differentiation and lipid homeostasis. Previous studies in Drosophila revealed that Seipin promotes ER calcium homeostasis through the Ca2+-ATPase SERCA, but little is known about the events downstream of perturbed ER calcium homeostasis that lead to decreased lipid storage in Drosophila dSeipin mutants. Here, we show that glycolytic metabolites accumulate and the downstream mitochondrial TCA cycle is impaired in dSeipin mutants. The impaired TCA cycle further leads to a decreased level of citrate, a critical component of lipogenesis. Mechanistically, Seipin/SERCA-mediated ER calcium homeostasis is important for maintaining mitochondrial calcium homeostasis. Reduced mitochondrial calcium in dSeipin mutants affects the TCA cycle and mitochondrial function. The lipid storage defects in dSeipin mutant fat cells can be rescued by replenishing mitochondrial calcium or by restoring the level of citrate through genetic manipulations or supplementation with exogenous metabolites. Together, our results reveal that Seipin promotes adipose tissue lipid storage via calcium-dependent mitochondrial metabolism.
Assuntos
Cálcio/metabolismo , Ciclo do Ácido Cítrico , Proteínas de Drosophila/metabolismo , Subunidades gama da Proteína de Ligação ao GTP/metabolismo , Metabolismo dos Lipídeos , Mitocôndrias/metabolismo , Tecido Adiposo/metabolismo , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster , Subunidades gama da Proteína de Ligação ao GTP/genética , Mitocôndrias/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismoRESUMO
Developmental biology research in China started from experimental embryology, in particular from studies on aquatic and reptile animals. The recent growth of the developmental biology community in China parallels the increased governmental funding support and the recruitment of overseas talents. This flourishing field in China embraces the activities of developmental biology-related societies, national meetings, key research initiatives and talented scientists. The first Development paper from China, published in 2000, marked the beginning of a new era. More recently, the second decade in the 21st century witnessed the blossoming of developmental biology research in China. Significant research spotlights, technical advances, and up-and-coming areas will be discussed in this overview.
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Biologia do Desenvolvimento , Flores , Animais , China , Biologia do Desenvolvimento/históriaRESUMO
BACKGROUND: Acute respiratory distress syndrome (ARDS) is a neutrophil-associated disease. Delayed neutrophil apoptosis and increased levels of neutrophil extracellular traps (NETs) have been described in ARDS. We aimed to investigate the relationship between these phenomena and their potential as inflammation drivers. We hypothesized that delayed neutrophil apoptosis might enhance NET formation in ARDS. METHOD: Our research was carried out in three aspects: clinical research, animal experiments, and in vitro experiments. First, we compared the difference between neutrophil apoptosis and NET levels in healthy controls and patients with ARDS and analyzed the correlation between neutrophil apoptosis and NET levels in ARDS. Then, we conducted animal experiments to verify the effect of neutrophil apoptosis on NET formation in Lipopolysaccharide-induced acute lung injury (LPS-ALI) mice. Furthermore, this study explored the relationship between neutrophil apoptosis and NETs at the cellular level. Apoptosis was assessed using morphological analysis, flow cytometry, and western blotting. NET formation was determined using immunofluorescence, PicoGreen assay, SYTOX Green staining, and western blotting. RESULTS: ARDS neutrophils lived longer because of delayed apoptosis, and the cyclin-dependent kinase inhibitor, AT7519, reversed this phenomenon both in ARDS neutrophils and neutrophils in bronchoalveolar lavage fluid (BALF) of LPS-ALI mice. Neutrophils in a medium containing pro-survival factors (LPS or GM-CSF) form more NETs, which can also be reversed by AT7519. Tissue damage can be reduced by promoting neutrophil apoptosis. CONCLUSIONS: Neutrophils with extended lifespan in ARDS usually enhance NET formation, which aggravates inflammation. Enhancing neutrophil apoptosis in ARDS can reduce the formation of NETs, inhibit inflammation, and consequently alleviate ARDS.
Assuntos
Armadilhas Extracelulares , Síndrome do Desconforto Respiratório , Animais , Apoptose , Humanos , Inflamação , Lipopolissacarídeos/toxicidade , Camundongos , Neutrófilos , Síndrome do Desconforto Respiratório/induzido quimicamenteRESUMO
Lipid droplets (LDs) are dynamic cytoplasmic organelles present in most eukaryotic cells. The appearance of LDs in neurons is not usually observed under physiological conditions, but is associated with neural diseases. It remains unclear how LD dynamics is regulated in neurons and how the appearance of LDs affects neuronal functions. We discovered that mutations of two key lipolysis genes atgl-1 and lid-1 lead to LD appearance in neurons of Caenorhabditis elegans. This neuronal lipid accumulation protects neurons from hyperactivation-triggered neurodegeneration, with a mild decrease in touch sensation. We also discovered that reduced biosynthesis of polyunsaturated fatty acids (PUFAs) causes similar effects and synergizes with decreased lipolysis. Furthermore, we demonstrated that these changes in lipolysis and PUFA biosynthesis increase PUFA partitioning toward triacylglycerol, and reduced incorporation of PUFAs into phospholipids increases neuronal protection. Together, these results suggest the crucial role of neuronal lipolysis in cell-autonomous regulation of neural functions and neurodegeneration.
Assuntos
Gotículas Lipídicas , Lipólise , Animais , Ácidos Graxos Insaturados/metabolismo , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos/genética , Neurônios , TriglicerídeosRESUMO
Adenovirus E1A-associated 300-kD protein (p300) bromodomain, which regulates gene expression by recognizing acetylated lysine (KAc) of histone, is a promising target for the treatment of cancer. Herein, a series of potent p300 bromodomain inhibitors with novel CBP30-based scaffolds was discovered through bioisosterism and conformational restriction strategies. The most promising compound 1u showed more potent inhibitory activity (IC50 = 49 nM) against p300 bromodomain and anti-proliferative activity in various cancer cell lines compared to CBP30. Moreover, 1u suppressed the expression of c-Myc and induced G1/G0 phase arrest and apoptosis in OPM-2 cells more potently than CBP30. This study provides new lead compounds for further research on the biological functions of p300.
Assuntos
Apoptose , Neoplasias , Benzimidazóis/farmacologia , Humanos , Domínios ProteicosRESUMO
p300/CBP bromodomain plays an important role in transcriptional regulation, and its overexpression is closely related to various diseases such as cancers. Two inhibitors of this target are currently in clinical trials but only CCS1477 (A1) have been published with the chemical structure. Herein, we modified the structure of CCS1477 based on the principle of bioisosterism and reasonable scaffold hopping, and discovered a series of new p300 bromodomain inhibitors with improved potency. More tumor cell lines sensitive to p300/CBP bromodomain inhibition were also identified. Among our new inhibitors, (R)-5-methylpyrrolidin-2-one derivitive B4 was the most potent one which showed comparable inhibitory activity against p300 (IC50 = 0.060 µM) as lead A1 (IC50 = 0.064 µM) at molecular level, and performed more potent proliferation inhibitory activities on various tumor cells than A1. Further we found that compound B4 had the high cell permeability and overcame the defect of the high efflux rate of A1, which could also explain the possible reason why B4 showed more potent inhibitory activities on sensitive tumor cells than lead A1. Western blotting analysis proved the target effects that B4 could suppress the expression of c-Myc and reduce H3K27 acetylation significantly. Liver microsomal metabolic stability assay and hERG channel inhibition evaluation illustrate compound B4 is metabolic stabilizable in human liver microsomes and has no hERG risk, which further demonstrate the good drug-likeness of B4. Therefore, compound B4 is a promising compound for further optimization and development.