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Protein-protein interactions play an important role in various biological processes. Interaction among proteins has a wide range of applications. Therefore, the correct identification of protein-protein interactions sites is crucial. In this paper, we propose a novel predictor for protein-protein interactions sites, AGF-PPIS, where we utilize a multi-head self-attention mechanism (introducing a graph structure), graph convolutional network, and feed-forward neural network. We use the Euclidean distance between each protein residue to generate the corresponding protein graph as the input of AGF-PPIS. On the independent test dataset Test_60, AGF-PPIS achieves superior performance over comparative methods in terms of seven different evaluation metrics (ACC, precision, recall, F1-score, MCC, AUROC, AUPRC), which fully demonstrates the validity and superiority of the proposed AGF-PPIS model. The source codes and the steps for usage of AGF-PPIS are available at https://github.com/fxh1001/AGF-PPIS.
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Benchmarking , Inibidores da Bomba de Prótons , Redes Neurais de Computação , SoftwareRESUMO
BACKGROUND: A promoter is a specific sequence in DNA that has transcriptional regulatory functions, playing a role in initiating gene expression. Identifying promoters and their strengths can provide valuable information related to human diseases. In recent years, computational methods have gained prominence as an effective means for identifying promoter, offering a more efficient alternative to labor-intensive biological approaches. RESULTS: In this study, a two-stage integrated predictor called "msBERT-Promoter" is proposed for identifying promoters and predicting their strengths. The model incorporates multi-scale sequence information through a tokenization strategy and fine-tunes the DNABERT model. Soft voting is then used to fuse the multi-scale information, effectively addressing the issue of insufficient DNA sequence information extraction in traditional models. To the best of our knowledge, this is the first time an integrated approach has been used in the DNABERT model for promoter identification and strength prediction. Our model achieves accuracy rates of 96.2% for promoter identification and 79.8% for promoter strength prediction, significantly outperforming existing methods. Furthermore, through attention mechanism analysis, we demonstrate that our model can effectively combine local and global sequence information, enhancing its interpretability. CONCLUSIONS: msBERT-Promoter provides an effective tool that successfully captures sequence-related attributes of DNA promoters and can accurately identify promoters and predict their strengths. This work paves a new path for the application of artificial intelligence in traditional biology.
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Regiões Promotoras Genéticas , Biologia Computacional/métodos , DNA/genética , Humanos , Modelos Genéticos , Análise de Sequência de DNA/métodosRESUMO
RNA-seq has been widely used to reveal the molecular mechanism of variants of life process. We have developed an alternative method, MustSeq, which generates multiple second strands along a single 1st strand cDNA by random-priming initiation, immediately after reverse transcription for each RNA extract using sample-barcoded poly-dT primers, then 3' ends-enriching PCR is applied to construct the library. Unlike the conventional RNA seq, MustSeq avoids procedures such as mRNA isolation, fragmentation and RNA 5'-end capture, enables early pooling of multiple samples, and requires only one twentieth of sequencing reads of full-length sequencing. We demonstrate the power and features of MustSeq comparing with TruSeq and NEBNext RNA-seq, two conventional full-length methods and QuantSeq, an industrial 3' end method. In cancer cell lines, the reads distribution of CDS-exon as well as genes, lncRNAs and GO terms detected by MustSeq are closer than QuantSeq to TruSeq. In mouse hepatocarcinoma and healthy livers, MustSeq enriches the same pathways as by NEBNext, and reveals the molecular profile of carcinogenesis. Overall MustSeq is a robust and accurate RNA-seq method allowing efficient library construction, sequencing and analysis, particularly valuable for analysis of differentially expressed genes with a large number of samples. MustSeq will greatly accelerate the application of bulk RNA-seq on different fields, and potentially applicable for single cell RNA-seq.
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Regiões 3' não Traduzidas/genética , RNA Mensageiro/genética , RNA-Seq/métodos , Análise de Sequência de RNA/métodos , Transcriptoma , Animais , Biblioteca Gênica , Células HeLa , Humanos , Células Jurkat , Células K562 , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/análiseRESUMO
Chitin deacetylases (CDAs, EC 3.5.1.41) catalyze the N-deacetylation of chitin to produce chitosan, which is essential for insect survival. Hence, CDAs are promising targets for the development of novel insecticidal drugs. In this study, the putative Group I chitin deacetylase genes HpCDA1, HpCDA2-1 and HpCDA2-2 were identified from Holotrichia parallela. Conserved domain database search identified a chitin-binding peritrophin-A domain (ChBD), a low-density lipoprotein receptor class A domain (LDLa), and a putative CDA-like catalytic domain. RT-qPCR analysis showed that the Group I HpCDAs were expressed in various tissues and predominant in the integument. The developmental expression patterns from the first-instar to third-instar larvae showed that HpCDAs were highly expressed on the first day and gradually declined after molting. The functional characteristics of the Group I CDAs in cuticle organization were examined using RNA interference (RNAi) and transmission electron microscopy (TEM) methods. Administration of double-stranded HpCDA (dsHpCDA) through larval injection could suppress the expression levels of HpCDA1 and HpCDA2, thus resulting in abnormal or lethal phenotypes. TEM analysis revealed that RNAi of either HpCDA1 or HpCDA2 remarkably affected the cuticle integrity, as evidenced by cuticle disorganization and chitin laminae disruption, suggesting the crucial role of CDAs in chitin modification. These experimental results demonstrate the important contribution of putative key genes involved in chitin metabolism, and provide a foundation for developing new strategies to control H. parallela.
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Besouros , Amidoidrolases/genética , Amidoidrolases/metabolismo , Animais , Quitina/metabolismo , Besouros/genética , Besouros/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Interferência de RNARESUMO
Cardiac ischemia-reperfusion (I/R) injury always accompanies recanalization treatment for myocardial infarction. Here we found soluble epoxide hydrolase (sEH), which metabolizes cardioprotective epoxyeicosatrienoic acids into less effective diols, was rapidly activated during myocardial reperfusion in both mouse and rat models in expression-independent manner. Similar activation was mimicked by nitric oxide (NO) donor dose-dependently in vitro, along with an obvious induction of sEH S-nitrosation, a short-term post-translational modification, which diminished in sEH Cys-141-Ala mutant. In vivo, I/R induced sEH S-nitrosation could be reversed by NO synthase inhibitor L-NAME, with protective effect on cardiac dysfunction, which however vanished in sEH-/- mice. Further, a protective effect against I/R injury in the initial phase of reperfusion was observed in eNOS-/- mice, indicating inhibition of NO as a sEH-based cardioprotective in early time of I/R injury. Besides, sEH inhibitor directly targeting on activated sEH during cardiac reperfusion significant reduced infarct size after I/R in vivo. In summary, our findings show the critical role of sEH S-nitrosation in cardiac I/R injury and inhibiting sEH S-nitrosation may be a new therapeutic strategy clinically.
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Epóxido Hidrolases/metabolismo , Traumatismo por Reperfusão Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/patologia , Animais , Cisteína/metabolismo , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Epóxido Hidrolases/antagonistas & inibidores , Hipóxia/patologia , Masculino , Camundongos Endogâmicos C57BL , Mutação/genética , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miocárdio/metabolismo , Miocárdio/patologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Nitrosação , Oxigênio/metabolismo , Compostos de Fenilureia/farmacologia , Compostos de Fenilureia/uso terapêutico , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Ratos Sprague-Dawley , S-Nitrosoglutationa/farmacologia , SolubilidadeRESUMO
The insect gut is home to an extensive array of microbes that play a crucial role in the digestion and absorption of nutrients, as well as in the protection against pathogenic microorganisms. The variety of these gut microbes is impacted by factors such as age, diet, pesticides, antibiotics, sex, and caste. Increasing evidence indicates that disturbances in the gut microbiota can lead to compromised insect health, and that its diversity has a far-reaching impact on the host's health. In recent years, the use of molecular biology techniques to conduct rapid, qualitative, and quantitative research on the host intestinal microbial diversity has become a major focus, thanks to the advancement of metagenomics and bioinformatics technologies. This paper reviews the main functions, influencing factors, and detection methods of insect gut microbes, in order to provide a reference and theoretical basis for better research utilization of gut microbes and management of harmful insects.
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Aeolian dust can provide nutrients for the ocean and affect the growth of phytoplankton. However, the impacts of dust deposition on autotrophic and heterotrophic microorganisms have rarely been studied. In this study, we conducted two microcosm experiments in the low-nutrient and low-chlorophyll environment of the South China Sea and found that dust did not stimulate the abundance of autotrophic and heterotrophic microorganisms. Our results show that dust contains most of the unreacted iron-bearing minerals, and thus provides limited bioavailable iron and nitrogen for bacterioplankton and phytoplankton growth. These results elucidate the overlooked impacts of the properties of the iron-bearing minerals in aeolian dust on microbial communities, which may play an important role in marine ecosystems and climate change.
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Microbiota , Água do Mar , Poeira/análise , Minerais , Ferro/análise , Fitoplâncton , ChinaRESUMO
The gut microbiota is essential for the growth and development of insects, and the intestinal immune system plays a critical role in regulating the homeostasis of intestinal microorganisms and their interactions with pathogenic bacteria. Infection with Bacillus thuringiensis (Bt) can disrupt the gut microbiota of insects, but the regulatory factors governing the interaction between Bt and gut bacteria are not well understood. Uracil secreted by exogenous pathogenic bacteria can activate DUOX-mediated reactive oxygen species (ROS) production, which helps maintain intestinal microbial homeostasis and immune balance. To elucidate the regulatory genes involved in the interaction between Bt and gut microbiota, we investigate the effects of uracil derived from Bt on gut microbiota, and host immunity using a uracil deficient Bt strain (Bt GS57â³pyrE) obtained by homologous recombination. We analyze the biological characteristics of the uracil deficient strain and found that the deletion of uracil in Bt GS57 strain changed the diversity of gut bacteria in Spodoptera exigua, as investigated using Illumina HiSeq sequencing. Furthermore, qRT-PCR analysis showed that compared with Bt GS57 (control), the expression of the SeDuox gene and the level of ROS were significantly decreased after feeding with Bt GS57â³pyrE. Adding uracil to Bt GS57â³pyrE restored the expression level of DUOX and ROS to a higher level. Additionally, we observed that PGRP-SA, attacin, defensin and ceropin genes were significant different in the midgut of S. exigua infected by Bt GS57 and Bt GS57â³pyrE, with a trend of increasing first and then decreasing. These results suggest that uracil regulates and activates the DUOX-ROS system, affects the expression of antimicrobial peptide genes, and disturb intestinal microbial homeostasis. We preliminarily speculate that uracil is a key factor in the interaction between Bt and gut microbiota, and these findings provide a theoretical basis for clarifying the interaction between Bt, host, and intestinal microorganisms, as well as for gaining new insights into the insecticidal mechanism of B. thuringiensis in insects.
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[This corrects the article DOI: 10.3389/fphar.2022.801350.].
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The Beet armyworm Spodoptera exigua (Lepidoptera: Noctuidae, Spodoptera) is an important global polyphagous pest. Pathogen infection could destroy the intestinal microbial homeostasis of insects, leading to the death of the host. However, the effect of the host intestinal microbial community on the insecticidal effect of Bacillus thuringiensis is rarely studied. In this study, the genome characteristics of Bt GS57 and the diversity and functions of the gut bacteria in S. exigua are investigated using crystal morphology, biological activity, and Illumina HiSeq high-throughput sequencing. The total size of the Bt GS57 genome is 6.17 Mbp with an average G + C content of 35.66%. Furthermore, the Bt GS57 genome contains six cry genes: cry1Ca, cry1Da, cry2Ab, cry9Ea, cry1Ia, and cry1Aa, and a vegetative insecticidal protein gene vip3Aa. The Bt GS57 strain can produce biconical crystals, mainly expressing 70 kDa and 130 kDa crystal proteins. The LC50 value of the Bt GS57 strain against the S. exigua larvae was 0.339 mg mL-1. Physiological and biochemical reactions showed that Bt GS57 belongs to B.t. var. thuringiensis. In addition, we found that B. thuringiensis can cause a dynamic change in the gut microbiota of S. exigua, with a significant reduction in bacterial diversity and a substantial increase in bacterial load. In turn, loss of gut microbiota significantly decreased the B. thuringiensis susceptibility of S. exigua larvae. Our findings reveal the vital contribution of the gut microbiota in B. thuringiensis-killing activity, providing new insights into the mechanisms of B. thuringiensis pathogenesis in insects.
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As a systemic inflammatory arthritis disease, rheumatoid arthritis (RA) is complex and hereditary. Traditional Chinese medicine (TCM) has evident advantages in treating complex diseases, and a variety of TCM formulas have been reported that have effective treatment on RA. Clinical and pharmacological studies showed that Ermiao Powder, which consists of Phellodendron amurense Rupr. (PAR) and Atractylodes lancea (Thunb.) DC. (ALD), can be used in the treatment of RA. Currently, most studies focus on the anti-inflammatory mechanism of PAR and ALD and are less focused on their coordinated molecular mechanism. In this research, we established an integrative pharmacological strategy to explore the coordinated molecular mechanism of the two herbs of Ermiao Powder in treating RA. To explore the potential coordinated mechanism of PAR and ALD, we firstly developed a novel mathematical model to calculate the contribution score of 126 active components and 85 active components, which contributed 90% of the total contribution scores that were retained to construct the coordinated functional space. Then, the knapsack algorithm was applied to identify the core coordinated functional components from the 85 active components. Finally, we obtained the potential coordinated functional components group (CFCG) with 37 components, including wogonin, paeonol, ethyl caffeate, and magnoflorine. Also, functional enrichment analysis was performed on the targets of CFCG to explore the potential coordinated molecular mechanisms of PAR and ALD. The results indicated that the CFCG could treat RA by coordinated targeting to the genes involved in immunity and inflammation-related signal pathways, such as phosphatidylinositol 3kinase/protein kinase B signaling pathway, mitogen-activated protein kinase signaling pathway, tumor necrosis factor signaling pathway, and nuclear factor-kappa B signaling pathway. The docking and in vitro experiments were used to predict the affinity and validate the effect of CFCG and further confirm the reliability of our method. Our integrative pharmacological strategy, including CFCG identification and verification, can provide the methodological references for exploring the coordinated mechanism of TCM in treating complex diseases and contribute to improving our understanding of the coordinated mechanism.
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Light fields are vector functions that map the geometry of light rays to the corresponding plenoptic attributes. They describe the holographic information of scenes by representing the amount of light flowing in every direction through every point in space. The physical concept of light fields was first proposed in 1936, and light fields are becoming increasingly important in the field of computer graphics, especially with the fast growth of computing capacity as well as network bandwidth. In this article, light field imaging is reviewed from the following aspects with an emphasis on the achievements of the past five years: (1) depth estimation, (2) content editing, (3) image quality, (4) scene reconstruction and view synthesis, and (5) industrial products because the technologies of lights fields also intersect with industrial applications. State-of-the-art research has focused on light field acquisition, manipulation, and display. In addition, the research has extended from the laboratory to industry. According to these achievements and challenges, in the near future, the applications of light fields could offer more portability, accessibility, compatibility, and ability to visualize the world.
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BACKGROUND: Increasing evidence indicated that metabolic reprograming is essential and has been regarded as a hallmark of cancer. Although the biological functions of Myosin 1b (Myo1b) have been reported in several malignancies, the correlation between Myo1b and cancer metabolism, and its underlying mechanisms remain elusive, particularly in cervical cancer (CC). METHODS: Myo1b and other glycolytic enzymes expression levels were examined in CC cells and tumor tissues from xenograft models by quantitative real-time PCR, Western blot and immunohistochemistry. The biological impacts and regulatory mechanisms of Myo1b on cell migration, invasion and glycolysis were explored. Also, the effects of Myo1b on carcinogenesis and metastasis in nude mice were investigated. RESULTS: Upregulation of Myo1b was found in CC tissues and associated with poor prognosis. Overexpressed Myo1b not only significantly elevated CC cell glycolysis, migration and invasion in vitro, but also promoted tumorigenesis and metastasis in vivo. Conversely, Myo1b knockdown had opposite consequences. Moreover, our study suggested that Myo1b stimulated ERK/HIF-1α pathway and its downstream glycolysis associated genes to modulate the glycolysis, migration and invasion of CC. CONCLUSION: These findings provide evidence that Myo1b regulates migration, invasion and glycolysis in CC through ERK/HIF-1α pathway, suggesting a promising remedial target in treatment of CC.
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In the dairy industry, glutamine (Gln) is often used as a feed additive to increase milk yield and quality; however, the molecular regulation underneath needs further clarification. Here, with bovine mammary epithelial cells (BMECs), the effects and mechanisms of Gln on cell growth and casein synthesis were assessed. When Gln was added or depleted from BMECs, both cell growth and ß-casein (CSN2) expression were increased or decreased, respectively. Overexpressing or inhibiting the mechanistic target of rapamycin (mTOR) revealed that Gln regulated cell growth and CSN2 synthesis through the mTORC1 pathway. A similar intervention of ADP-ribosylation factor 1 (Arf1) uncovered that Gln activated the mTORC1 pathway through Arf1. We next observed that both guanine nucleotide exchange factors, Cytohesin-1/2/3 (CYTH1/2/3, CYTHs) and ADP-ribosylation factor GTPase activating protein 1 (ARFGAP1), interacted with Arf1. Inhibiting CYTHs or ARFGAP1 showed that Gln supplement or depletion activated or inactivated Arf1 through CYTHs or ARFGAP1, respectively. Collectively, this study demonstrated that Gln positively regulated cell growth and casein synthesis in BMECs, which works through the CYTHs/ARFGAP1-Arf1-mTORC1 pathway. These results greatly enhanced current understanding regarding the regulation of the mTOR pathway and provided new insights for the processes of cell growth and casein synthesis by amino acids, particularly Gln.
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Fator 1 de Ribosilação do ADP , Caseínas , Animais , Caseínas/metabolismo , Bovinos , Células Epiteliais/metabolismo , Glutamina , Glândulas Mamárias Animais/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Transdução de SinaisRESUMO
BACKGROUND: Since the People's Republic of China (PRC), or China, established the basic medical insurance system (MIS) in 1998, the medical insurance information systems (MIISs) in China have effectively supported the operation of the MIS through several phases of development; the phases included a stand-alone version, the internet, and big data. In 2018, China's national medical security systems were integrated, while MIISs were facing reconstruction. We summarized China's experience in medical insurance informatization over the past 20 years, aiming to provide a reference for the building of a new basic MIS for China and for developing countries. OBJECTIVE: This paper aims to sort out medical insurance informatization policies throughout the years, use questionnaires to determine the status quo of provincial MIIS-building in China and the relevant policies, provide references and suggestions for the top-level design and implementation of the information systems in the transitional period of China's MIS reform, and provide a reference for the building of MIISs in developing countries. METHODS: We conducted policy analysis by collecting the laws, regulations, and policy documents-issued from 1998 to 2020-on China's medical insurance and its informatization; we also analyzed the US Health Insurance Portability and Accountability Act and other relevant policies. We conducted a questionnaire survey by sending out questionnaires to 31 Chinese, provincial, medical security bureaus to collect information about network links, system functions, data exchange, standards and specifications, and building modes, among other items. We conducted a literature review by searching for documents about relevant laws and policies, building methods, application results, and other documents related to MIISs; we conducted searches using PubMed, Elsevier, China National Knowledge Infrastructure, and other major literature databases. We conducted telephone interviews to verify the results of questionnaires and to understand the focus issues concerning the building of China's national MIISs during the period of integration and transition of China's MIS. RESULTS: In 74% (23/31) of the regions in China, MIISs were networked through dedicated fiber optic lines. In 65% (20/31) of the regions in China, MIISs supported identity recognition based on both ID cards and social security cards. In 55% (17/31) of the regions in China, MIISs at provincial and municipal levels were networked and have gathered basic medical insurance data, whereas MIISs were connected to health insurance companies in 35% (11/31) of the regions in China. China's MIISs are comprised of 11 basic functional modules, among which the modules of business operation, transregional referral, reimbursement, and monitoring systems are widely applied. MIISs in 83% (20/24) of Chinese provinces have stored data on coverage, payment, and settlement compensation of medical insurance. However, in terms of data security and privacy protection, pertinent policies are absent and data utilization is not in-depth enough. Respondents to telephone interviews universally reflected on the following issues and suggestions: in the period of integration and transition of MISs, close attention should be paid to the top-level design, and repeated investment should be avoided for the building of MIISs; MIISs should be adapted to the health care reform, and efforts should be made to strengthen the informatization support for the reform of payment methods; and MIISs should be adapted for the widespread application of mobile phones and should provide insured persons with more self-service functions. CONCLUSIONS: In the future, the building of China's basic MIISs should be deployed at the national, provincial, prefectural, and municipal levels on a unified basis. Efforts should be made to strengthen the development of standard codes, data exchange, and data utilization. Work should be done to formulate the rules and regulations for security and privacy protection and to balance the right to be informed with the mining and utilization of big data. Efforts should be made to intensify the interconnectivity between MISs and other health systems and to strengthen the application of medical insurance information in public health monitoring and early warning systems; this would ultimately improve the degree of trust from stakeholders, including individuals, medical service providers, and public health institutions, in the basic MIISs.
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Krüppel-like factor 4 (KLF4) is a transcription factor with conserved zinc finger domains. As an essential regulator of vascular homeostasis, KLF4 exerts a protective effect in endothelial cells (ECs), including regulating vasodilation, inflammation, coagulation and oxidative stress. However, the underlying mechanisms modifying KLF4 activity in mediating vascular function remain poorly understood. Recently, essential roles for S-nitrosation have been implicated in many pathophysiologic processes of cardiovascular disease. Here, we demonstrated that KLF4 could undergo S-nitrosation in response to nitrosative stress in ECs, leading to the decreased nuclear localization with compromised transactivity. Mass-spectrometry and site-directed mutagenesis revealed that S-nitrosation modified KLF4 predominantly at Cys437. Functionally, KLF4 dependent vasodilatory response was impaired after S-nitrosoglutathione (GSNO) treatment. In ECs, endothelin-1 (ET-1) induced KLF4 S-nitrosation, which was inhibited by an endothelin receptor antagonist Bosentan. In hypoxia-induced rat model of pulmonary arterial hypertension (PAH), S-nitrosated KLF4 (SNO-KLF4) was significantly increased in lung tissues, along with decreased nuclear localization of KLF4. In summary, we demonstrated that S-nitrosation is a novel mechanism for the post-translational modification of KLF4 in ECs. Moreover, these findings suggested that KLF4 S-nitrosation may be implicated in the pathogenesis of vascular dysfunction and diseases such as PAH.
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Endotélio Vascular/metabolismo , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/fisiopatologia , Fatores de Transcrição Kruppel-Like/metabolismo , Animais , Cisteína/metabolismo , Células Endoteliais/metabolismo , Endotelina-1/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipertensão Pulmonar/etiologia , Fator 4 Semelhante a Kruppel , Masculino , Transporte Proteico , Ratos , Proteínas Recombinantes , Transcrição Gênica , VasodilataçãoRESUMO
Aging is tightly associated with redox events. The free radical theory of aging indicates that redox imbalance may be an important factor in the aging process. Most studies about redox and aging focused on the static status of oxidative stress levels, there has been little research investigating differential responses to redox challenge during aging. In this study, we used Caenorhabditis elegans and human fibroblasts as models to compare differential responses to oxidative stress challenge in young and old individuals. In response to paraquat stress, young individuals generated more ROS and activated signaling pathways including p-ERK, p-AKT and p-AMPKα/ß. After the initial response, young individuals then promoted NRF2 translocation and induced additional antioxidant enzymes and higher expression of phase II enzymes, including SOD, CAT, GPX, HO-1, GSTP-1and others, to maintain redox homeostasis. Moreover, young individuals also demonstrated a better ability to degrade damaged proteins by up-regulating the expression of chaperones and improving proteasome activity. Based on these data, we propose a new concept "Redox-stress Response Capacity (RRC)", which suggests cells or organisms are capable of generating dynamic redox responses to activate cellular signaling and maintain cellular homeostasis. The decay of RRC is the substantive characteristic of aging, which gives a new understand of the redox theory of aging.
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Envelhecimento/genética , Caenorhabditis elegans/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Paraquat/farmacologia , Quinases Proteína-Quinases Ativadas por AMP , Envelhecimento/metabolismo , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/metabolismo , Catalase/genética , Catalase/metabolismo , Senescência Celular/efeitos dos fármacos , Pré-Escolar , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Glutationa S-Transferase pi/genética , Glutationa S-Transferase pi/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Cultura Primária de Células , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismoRESUMO
The majority of diabetic patients develop neuropathy and there is an increasing prevalence of neurodegeneration in the central nervous system (CNS). However, the mechanism behind this is poorly understood. Here we first observed that macroautophagy/autophagy was suppressed in the hippocampus of diabetic GK rats with hyperglycemia, whereas it was unchanged in ob/ob mice without hyperglycemia. Autophagy could be directly inhibited by high glucose in mouse primary hippocampal neurons. Moreover, autophagy was protective in high-glucose-induced neurotoxicity. Further studies revealed that autophagic flux was suppressed by high glucose due to impaired autophagosome synthesis illustrated by mRFP-GFP-LC3 puncta analysis. We showed that decreased autophagy was dependent on NO produced under high glucose conditions. Therefore, (LC-MS/MS)-based quantitative proteomic analysis of protein S-nitrosation was performed and a core autophagy protein, ATG4B was found to be S-nitrosated in the hippocampus of GK rats. ATG4B was also verified to be S-nitrosated in neuronal cells cultured with high glucose. The activities of ATG4B in the processing of unmodified, precursor Atg8-family proteins and in the deconjugation of PE from lipidated Atg8-family proteins, which are essential for efficient autophagosome biogenesis were both compromised by S-nitrosation at Cys189 and Cys292 sites. In addition, ATG4B processing of the GABARAPL1 precursor was affected the least by S-nitrosation compared with other substrates. Finally, ATG4B S-nitrosation was verified to be responsible for decreased autophagy and neurotoxicity in response to high glucose. In conclusion, autophagy impairment mediated by S-nitrosation of ATG4B leads to neurotoxicity in response to hyperglycemia. Our research reveals a novel mechanism linking hyperglycemia with CNS neurotoxicity and shows that S-nitrosation is a novel post-transcriptional modification of the core autophagy machinery.
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Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Cisteína Endopeptidases/metabolismo , Hiperglicemia/metabolismo , Neurônios/metabolismo , Animais , Autofagossomos/metabolismo , Proteínas Relacionadas à Autofagia/química , Linhagem Celular , Sobrevivência Celular , Células Cultivadas , Cisteína/metabolismo , Cisteína Endopeptidases/química , Diabetes Mellitus Tipo 2/metabolismo , Glucose/toxicidade , Hipocampo/metabolismo , Humanos , Hiperglicemia/enzimologia , Masculino , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/enzimologia , Óxido Nítrico/metabolismo , Nitrosação , Ratos , Ratos WistarRESUMO
BACKGROUND: The New Rural Cooperative Medical Scheme (NCMS) has been further adjusted and optimized to reduce the financial burden of rural residents and to achieve universal coverage for them. In this study, we aimed to explore the impact of NCMS on medical service utilization and medical expense of inpatients in recent years. METHODS: The research data of Hainan Province were extracted from the Chinese NCMS platform from 2012 to 2014. Detailed information included total expenditure, average inpatients costs, average out-of-pocket payments, actual reimbursement rate, and average annual growth rate of the above indicators. Descriptive analysis was used to gauge the effects of NCMS. RESULTS: In the utilization of medical services, NCMS inpatients in tertiary hospital decreased from 25.49% in 2012 to 20.39% in 2014, inpatients in county hospitals increased from 39.49% to 55.92%, simultaneously. The total expenditure in county hospitals rose steadily from 28.46% to 46.66%, meanwhile, the total expenditure in tertiary hospitals fell from 60.44% to 44.51%.The average out-of-pocket costs of rural inpatients remained stable over the years. Furthermore, the compensation fund of NCMS inpatients grew significantly. The actual inpatient reimbursement rate at township health centers increased from 76.93% to 84.04%. Meanwhile, the rate at county hospitals and tertiary hospitals increased slightly from 59.37% and 46.10% to 61.25% and 47.71%, respectively. CONCLUSIONS: With the improvement of the reimbursement ability, especially after the new health care reform in 2009, the NCMS have been playing a prominent role in alleviating the economic burden of farmers' medical treatment. Meanwhile, more patients go to primary hospitals than tertiary hospitals, and the capability of primary hospitals has been greatly improved.
Assuntos
Gastos em Saúde/estatística & dados numéricos , Pacientes Internados/estatística & dados numéricos , China , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Seguro Saúde/economia , Masculino , População RuralRESUMO
Peroxisome proliferator-activated receptor-γ (PPARγ) is a ligand-activated nuclear receptor and plays an essential role in insulin signaling. Macrophage infiltration into adipose tissue is a character of metabolic inflammation and closely related to insulin resistance in type 2 diabetes. The mechanism by which pro-inflammatory macrophages cause insulin resistance remains to be elucidated. Here we showed that co-culture with macrophages significantly suppressed the transcriptional activity of PPARγ on its target genes in 3T3-L1 preadipocytes and diabetic primary adipocytes, depending on inducible nitric oxide synthase (iNOS). We further showed that PPARγ underwent S-nitrosylation in response to nitrosative stress. Mass-spectrometry and site-directed mutagenesis revealed that S-nitrosylation at cysteine 168 was responsible for the impairment of PPARγ function. Extended exposure to NO instigated the proteasome-dependent degradation of PPARγ. Consistently, in vivo evidence revealed an association of the decreased PPARγ protein level with increased macrophage infiltration in visceral adipose tissue (VAT) of obese diabetic db/db mice. Together, our results demonstrated that pro-inflammatory macrophages suppressed PPARγ activity in adipocytes via S-nitrosylation, suggesting a novel mechanism linking metabolic inflammation with insulin resistance.