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1.
Nat Commun ; 11(1): 978, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32080196

RESUMO

In order to maintain tissue homeostasis, cells communicate with the outside environment by receiving molecular signals, transmitting them, and responding accordingly with signaling pathways. Thus, one key challenge in engineering molecular signaling systems involves the design and construction of different modules into a rationally integrated system that mimics the cascade of molecular events. Herein, we rationally design a DNA-based artificial molecular signaling system that uses the confined microenvironment of a giant vesicle, derived from a living cell. This system consists of two main components. First, we build an adenosine triphosphate (ATP)-driven DNA nanogatekeeper. Second, we encapsulate a signaling network in the biomimetic vesicle, consisting of distinct modules, able to sequentially initiate a series of downstream reactions playing the roles of reception, transduction and response. Operationally, in the presence of ATP, nanogatekeeper switches from the closed to open state. The open state then triggers the sequential activation of confined downstream signaling modules.


Assuntos
DNA/metabolismo , Transdução de Sinais , Trifosfato de Adenosina/metabolismo , Células Artificiais/química , Materiais Biomiméticos/química , Biomimética/métodos , Homeostase , Nanoestruturas/química , Biologia Sintética/métodos
2.
Medicine (Baltimore) ; 98(50): e18325, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31852124

RESUMO

INTRODUCTION: Functional constipation (FC) is one of the common gastrointestinal disorders that affects people of almost every age. Persistent FC significantly affects quality of life and well-being along with economic burden on patients as well as health care system. Therapeutic efficacy of currently used treatment strategies becomes limited shortly after their discontinuation as constipation occurs again as a result of inappropriate dietary habits. Previous studies have revealed that light vegetarian diet (LVD) can significantly improve both typical and atypical subtypes of major traditional Chinese medicine (TCM) FC syndrome such as gastrointestinal damp-heat syndrome. This protocol aims at exploratorily investigating effectiveness and safety of LVD following a rigorous clinical trial. METHODS AND DESIGN: Total 92 patients in each of the 2 subtypes will be recruited in China-Japan Friendship Hospital for participating in this prospective, placebo-controlled, randomized trial and exploratory study. The patients in each subtype will be randomly divided into 4 groups according to 1:1:1:1 ratio with allocation concealment, which are drug + diet group, drug group, placebo + diet group and placebo group. Patients in the group with diet intervention will be required to strictly follow the LVD. The study will continue for a period of 28 days, including a drug or placebo supervised intervention and a 14th-day telephone follow-up. During the intervention, patients will be required to record a designed diary for controlling the diet quality (DQ) and analyzing the defecation. The study will focus investigation of complete spontaneous bowel movements (CSBM) per week as its primary outcome and constipation-related symptom rating scale (CSS), TCM syndrome scale (TCMSS), 48-hour gastrointestinal transit time (48-hour GITT), high resolution anorectal manometry (HRAM) and fecal flora detection (FFD) will be included in secondary outcomes. Furthermore, the study will also determine safety, DQ and compliance indicators. ETHICS AND DISSEMINATION: This study has been approved by China-Japan Friendship Hospital clinical research ethics committee (No. 2017-46-1). A SPIRIT checklist is available for this protocol. TRIAL REGISTRATION NUMBER: ChiCTR1800019686 in Chinese Clinical Trial Registry (WHO ICTRP member).


Assuntos
Constipação Intestinal/terapia , Dieta Vegetariana/métodos , Gastroenteropatias/terapia , Adulto , Constipação Intestinal/fisiopatologia , Defecação , Feminino , Gastroenteropatias/fisiopatologia , Trato Gastrointestinal/fisiopatologia , Humanos , Masculino , Medicina Tradicional Chinesa , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Índice de Gravidade de Doença , Síndrome , Resultado do Tratamento
3.
Sci Rep ; 9(1): 19546, 2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31862909

RESUMO

Sperm storage in the female reproductive tract after mating and before ovulation is a reproductive strategy used by many species. When insemination and ovulation are poorly synchronized, the formation and maintenance of a functional sperm reservoir improves the possibility of fertilization. In mammals, the oviduct regulates sperm functions, such as Ca2+ influx and processes associated with sperm maturation, collectively known as capacitation. A fraction of the stored sperm is released by unknown mechanisms and moves to the site of fertilization. There is an empirical association between the hormonal milieu in the oviduct and sperm detachment; therefore, we tested directly the ability of progesterone to induce sperm release from oviduct cell aggregates. Sperm were allowed to bind to oviduct cells or an immobilized oviduct glycan and then challenged with progesterone, which stimulated the release of 48% of sperm from oviduct cells or 68% of sperm from an immobilized oviduct glycan. The effect of progesterone on sperm release was specific; pregnenolone and 17α-OH-progesterone did not affect sperm release. Ca2+ influx into sperm is associated with capacitation and development of hyperactivated motility. Progesterone increased sperm intracellular Ca2+, which was abrogated by blocking the sperm-specific Ca2+ channel CatSper with NNC 055-0396. NNC 055-0396 also blocked the progesterone-induced sperm release from oviduct cells or immobilized glycan. An inhibitor of the non-genomic progesterone receptor that activates CatSper similarly blocked sperm release. This is the first report indicating that release of sperm from the sperm reservoir is induced by progesterone action through CatSper channels.

4.
Front Immunol ; 10: 2281, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31608065

RESUMO

Background: Accumulating evidence suggests that differentially expressed non-coding circular RNAs (circRNAs) play critical roles in the progress of autoimmune diseases. However, the role of circRNAs in systemic lupus erythematosus (SLE) remains unclear. Methods: We initially used next-generation sequencing (NGS) to comprehensively analyze circRNA expression profiles in peripheral blood mononuclear cells (PBMCs) from 10 SLE patients, stratified by their disease activity characteristics (stable or active SLE), and 10 healthy controls (HCs). Candidate circRNAs identified were first validated by quantitative reverse-transcription (qRT)-PCR in PBMC samples from a training-phase cohort of five SLE patients and five HCs. The significantly dysregulated circRNAs were then confirmed by qRT-PCR in a validation cohort of 23 SLE patients and 21 HCs, and in an external validation cohort with 64 SLE patients, 58 HCs, and 50 patients with rheumatoid arthritis (RA). In addition, we conducted bioinformatics analysis and western blotting investigating the relationships between the candidate circRNAs and SLE progression. Results: Multilayer integrative analysis of circRNA regulation showed that 84 circRNAs were upregulated and 30 were downregulated in patients with SLE compared with HCs. We then analyzed the intersection of these differentially expressed circRNAs in an SLE-stable cohort, an SLE-active cohort, and HCs. This enabled us to narrow down dysregulated circRNAs to 15 upregulated circRNAs. Only hsa_circ_0000479 was significantly upregulated in PBMCs of patients with SLE compared with HCs (P < 0.05). Furthermore, the diagnostic potential of hsa_circ_0000479 expression to distinguish SLE patients from HCs and RA patients was also significantly increased in the validation-phase and external-validation-phase cohorts (P < 0.05). When distinguishing SLE patients from HCs, the diagnostic specificities of hsa_circ_0000479 were 0.619 and 1.0 in two validation cohorts, respectively (AUCs = 0.731 and 0.730, respectively). It was also significantly increased in either stable SLE patients or active SLE patients compared with HCs in these two cohorts (P < 0.05). We also used bioinformatics analysis to show that hsa_circ_0000479 regulates SLE progression by modulating metabolic pathways and the Wnt signaling pathway. Western blotting revealed that the expression of Wnt-16 protein was significantly decreased in SLE. Conclusion: Our results suggest that hsa_circ_0000479 has potential as a novel biomarker for the diagnosis of SLE.

5.
Research (Wash D C) ; 2019: 6523970, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31549076

RESUMO

Biomimetic giant membrane vesicles, with size and lipid compositions comparable to cells, have been recognized as an attractive experimental alternative to living systems. Due to the similarity of their membrane structure to that of body cells, cell-derived giant plasma membrane vesicles have been used as a membrane model for studying lipid/protein behavior of plasma membranes. However, further application of biomimetic giant membrane vesicles has been hampered by the side-effects of chemical vesiculants and the utilization of osmotic buffer. We herein develop a facile strategy to derive giant membrane vesicles (GMVs) from mammalian cells in biofriendly medium with high yields. These GMVs preserve membrane properties and adaptability for surface modification and encapsulation of exogenous molecules, which would facilitate their potential biological applications. Moreover, by loading GMVs with therapeutic drugs, GMVs could be employed for drug transport to tumor cells, which represents another step forward in the biomedical application of giant membrane vesicles. This study highlights biocompatible GMVs with biomimicking membrane surface properties and adaptability as an ideal platform for drug delivery strategies with potential clinical applications.

6.
Org Lett ; 21(19): 8080-8084, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31545060

RESUMO

The syntheses of linoleic acid esters of hydroxy linoleic acids (LAHLAs) present in oat oil and human serum have been achieved, providing access to material for testing and the determination of the stereochemistry of the natural compounds. While 9- and 13-LAHLAs were found to be a mixture of enantiomers 15-LAHLA is generated in a single optical form in oat oil. The stereochemistry of 15-LAHLA in oat oil was found to be opposite to that reported for digalactosyldiacylglycerol that possesses an embedded 15-LAHLA.

7.
Curr Top Med Chem ; 19(21): 1918-1947, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31393249

RESUMO

microRNAs (miRNAs) are an evolutionarily conserved class of small single-stranded noncoding RNAs. The aberrant expression of specific miRNAs has been implicated in the development and progression of diverse cardiovascular diseases. For many decades, miRNA therapeutics has flourished, taking advantage of the fact that miRNAs can modulate gene expression and control cellular phenotypes at the posttranscriptional level. Genetic replacement or knockdown of target miRNAs by chemical molecules, referred to as miRNA mimics or inhibitors, has been used to reverse their abnormal expression as well as their adverse biological effects in vitro and in vivo in an effort to fully implement the therapeutic potential of miRNA-targeting treatment. However, the limitations of the chemical structure and delivery systems are hindering progress towards clinical translation. Here, we focus on the regulatory mechanisms and therapeutic trials of several representative miRNAs in the context of specific cardiovascular diseases; from this basic perspective, we evaluate chemical modifications and delivery vectors of miRNA-based chemical molecules and consider the underlying challenges of miRNA therapeutics as well as the clinical perspectives on their applications.


Assuntos
Fármacos Cardiovasculares/farmacologia , Doenças Cardiovasculares/tratamento farmacológico , MicroRNAs/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Bibliotecas de Moléculas Pequenas/química
8.
J Control Release ; 310: 103-114, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31425721

RESUMO

Synthetic chemically modified mRNAs (modRNA) encoding vascular endothelial growth factor (VEGF) represents an alternative to gene therapy for the treatment of ischemic cardiovascular injuries. However, novel delivery approaches of modRNA are needed to improve therapeutic efficacy in the diseased setting. We hypothesized that cell-mediated modRNA delivery may enhance the in vivo expression kinetics of VEGF protein thus promoting more potent angiogenic effects. Here, we employed skin fibroblasts as a "proof of concept" to probe the therapeutic potential of a cell-mediated mRNA delivery system in a murine model of critical limb ischemia (CLI). We show that fibroblasts pre-treated with VEGF modRNA have the potential to fully salvage ischemic limbs. Using detailed molecular analysis we reveal that a fibroblast-VEGF modRNA combinatorial treatment significantly reduced tissue necrosis and dramatically improved vascular densities in CLI-injured limbs when compared to control and vehicle groups. Furthermore, fibroblast-delivered VEGF modRNA treatment increased the presence of Pax7+ satellite cells, indicating a possible correlation between VEGF and satellite cell activity. Our study is the first to demonstrate that a cell-mediated modRNA therapy could be an alternative advanced strategy for cardiovascular diseases.

9.
Chem Commun (Camb) ; 55(71): 10623-10626, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31429452

RESUMO

The first example of transition-metal-catalyzed C-H activations of 2-phenylisatogens with alkynes and sulfonyl azides has been developed using N-oxide as the directing group. Ru(ii)-Catalyzed C-H alkenylation/cyclization and Ir(iii)-catalyzed direct C-H sulfamidation proceeded with good yields and excellent functional group tolerance. Importantly, these two transformations provided straightforward routes for the synthesis of indol-3-one derivatives and sulfamidated 2-phenylisatogens respectively, which might be of considerable bioactivities.

10.
J Cancer ; 10(15): 3450-3458, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293649

RESUMO

Accumulating evidence from clinical trials indicates chronic hepatitis B virus (HBV) infection is associated with the incidence of diffuse large B-cell lymphoma (DLBCL) and may be associated with the prognosis of DLBCL, though this suggestion remains controversial. We performed a meta-analysis to assess whether HBV infection is associated with prognosis and response to chemotherapy in DLBCL. After a strict literature search strategy, a total of 809 HBV surface antigen (HBsAg) seropositive patients with DLBCL and 2849 HBsAg seronegative patients with DLBCL from twelve trials were included. DLBCL patients with chronic HBV infection had significantly poorer 2- and 5-year overall survival (OS) (HR 1.54, 95% CI 1.23-1.92, P<0.001 and 1.79, 1.48-2.17, P<0.001) and 2- and 5-year progression-free survival (PFS) (HR 1.44, 95% CI 1.14-1.81, P=0.002 and HR 1.34, 95% CI 1.02-1.75, P=0.03). HBsAg-seronegative patients also had a lower complete response (CR) rate (OR 0.48, 95% CI 0.34-0.68, P<0.001), higher progressive disease (PD) rate (OR 2.08, 95% CI 1.34-3.24, P=0.001), and more advanced clinical features. This meta-analysis indicates HBV infection leads to a poorer prognosis and poorer response to standard chemotherapy.

11.
J Biol Chem ; 294(27): 10698-10707, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31152059

RESUMO

Fatty acid esters of hydroxy fatty acids (FAHFAs) are a recently discovered class of biologically active lipids. Here we identify the linoleic acid ester of 13-hydroxy linoleic acid (13-LAHLA) as an anti-inflammatory lipid. An oat oil fraction and FAHFA-enriched extract from this fraction showed anti-inflammatory activity in a lipopolysaccharide-induced cytokine secretion assay. Structural studies identified three LAHLA isomers (15-, 13-, and 9-LAHLA) as being the most abundant FAHFAs in the oat oil fraction. Of these LAHLAs, 13-LAHLA is the most abundant LAHLA isomer in human serum after ingestion of liposomes made of fractionated oat oil, and it is also the most abundant endogenous LAHLA in mouse and human adipose tissue. As a result, we chemically synthesized 13-LAHLA for biological assays. 13-LAHLA suppresses lipopolysaccharide-stimulated secretion of cytokines and expression of pro-inflammatory genes. These studies identify LAHLAs as an evolutionarily conserved lipid with anti-inflammatory activity in mammalian cells.

12.
J Antibiot (Tokyo) ; 72(6): 498-506, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30988370

RESUMO

Fatty acid esters of hydroxy fatty acids (FAHFAs) are a growing class of natural products found in organisms ranging from plants to humans. The roles these endogenous derivatives of fatty acids play in biology and their novel pathways for controlling inflammation have increased our understanding of basic human physiology. FAHFAs incorporate diverse fatty acids into their structures, however, given their recent discovery non-natural derivatives have not been a focus and as a result structure-activity relationships remain unknown. The importance of the long chain hydrocarbons extending from the ester linkage as they relate to anti-inflammatory activity is unknown. Herein the systematic removal of carbons from either the hydroxy fatty acid or fatty acid regions of the most studied FAHFA, palmitic acid ester of 9-hydroxystearic acid (9-PAHSA), was achieved and these synthetic, abridged analogs were tested for their ability to attenuate IL-6 production. Reduction of the carbon chain lengths of the 9-hydroxystearic acid portion or palmitic acid hydrocarbon chain resulted in lower molecular weight analogs that maintained anti-inflammatory activity or in one case enhanced activity.


Assuntos
Anti-Inflamatórios/síntese química , Anti-Inflamatórios/farmacologia , Ácido Palmítico/química , Ácido Palmítico/farmacologia , Ácidos Esteáricos/química , Ácidos Esteáricos/farmacologia , Animais , Anti-Inflamatórios/química , Camundongos , Estrutura Molecular , Células RAW 264.7 , Relação Estrutura-Atividade
13.
J Transl Med ; 16(1): 370, 2018 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-30577810

RESUMO

BACKGROUND: Systemic lupus erythematosus (SLE) is a multisystemic autoimmune disease with various clinical manifestations. MicroRNAs (miRNAs) and immunometabolism are recognized as key elements in SLE pathogenesis; however, the relationship between miRNAs in peripheral blood mononuclear cells (PBMCs) and metabolism in SLE remains unclear. METHODS: We detected PBMC miRNA and mRNA profiles from 3 pooled SLE patients and 3 healthy controls (HCs) using next-generation sequencing, predicted miRNA targets in dysregulated mRNAs, predicted functions and interactions of differentially expressed genes using bioinformatics analysis, validated candidate miRNAs using qRT-PCR, and investigated the association between the expression of candidate miRNAs and SLE clinical characteristics. Moreover, we validated the direct and transcriptional regulatory effect of NovelmiRNA-25 on adenosine monophosphate deaminase 2 (AMPD2) using a dual-luciferase reporter assay and western blot and confirmed AMPD2 mRNA and protein expression in PBMCs using qRT-PCR and western blot, respectively. RESULTS: Multilayer integrative analysis of microRNA and mRNA regulation showed that 10 miRNAs were down-regulated and 19 miRNAs were up-regulated in SLE patient PBMCs compared with HCs. Bioinformatics analysis of regulatory networks between miRNAs and mRNAs showed that 19 miRNAs were related to metabolic processes. Two candidate miRNAs, NovelmiRNA-25 and miR-1273h-5p, which were significantly increased in the PBMCs of SLE patients (P < 0.05), represented diagnostic biomarkers with sensitivities of 94.74% and 89.47%, respectively (area under the curve = 0.574 and 0.788, respectively). NovelmiRNA-25 expression in PBMCs was associated with disease activity in SLE patients, in both active and stable groups (P < 0.05). NovelmiRNA-25 overexpression downregulated AMPD2 expression in HEK293T cells through direct targeting of the AMPD2 3'UTR (P < 0.01), while inhibition of NovelmiRNA-25 activity led to increased AMPD2 expression (P < 0.01). NovelmiRNA-25 overexpression also downregulated AMPD2 protein expression in HEK293T cells; AMPD2 protein expression in SLE patient PBMCs was decreased. Our results show that differentially expressed miRNAs play an important role in SLE. CONCLUSIONS: Our data demonstrate a novel mechanism in SLE development that involves the targeting of AMPD2 expression by NovelmiRNA-25. miRNAs may serve as novel biomarkers for the diagnosis and evaluation of disease activity of SLE and represent potential therapeutic targets for this disease.


Assuntos
AMP Desaminase/sangue , Leucócitos Mononucleares/metabolismo , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/genética , MicroRNAs/metabolismo , Sequência de Bases , Biomarcadores/sangue , Estudos de Casos e Controles , Ontologia Genética , Redes Reguladoras de Genes , Células HEK293 , Humanos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
14.
Patient Prefer Adherence ; 12: 1757-1765, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30237698

RESUMO

Purpose: The aim of this study was to develop and internally validate a medication nonadherence risk nomogram in a Chinese population of patients with inflammatory rheumatic diseases. Patients and methods: We developed a prediction model based on a training dataset of 244 IRD patients, and data were collected from March 2016 to May 2016. Adherence was evaluated using 19-item Compliance Questionnaire Rheumatology. The least absolute shrinkage and selection operator regression model was used to optimize feature selection for the medication nonadherence risk model. Multivariable logistic regression analysis was applied to build a predicting model incorporating the feature selected in the least absolute shrinkage and selection operator regression model. Discrimination, calibration, and clinical usefulness of the predicting model were assessed using the C-index, calibration plot, and decision curve analysis. Internal validation was assessed using the bootstrapping validation. Results: Predictors contained in the prediction nomogram included use of glucocorticoid (GC), use of nonsteroidal anti-inflammatory drugs, number of medicine-related questions, education level, and the distance to hospital. The model displayed good discrimination with a C-index of 0.857 (95% confidence interval: 0.807-0.907) and good calibration. High C-index value of 0.847 could still be reached in the interval validation. Decision curve analysis showed that the nonadherence nomogram was clinically useful when intervention was decided at the nonadherence possibility threshold of 14%. Conclusion: This novel nonadherence nomogram incorporating the use of GC, the use of nonsteroidal anti-inflammatory drugs, the number of medicine-related questions, education level, and distance to hospital could be conveniently used to facilitate the individual medication nonadherence risk prediction in IRD patients.

15.
PLoS Comput Biol ; 14(8): e1006380, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30133447

RESUMO

The molecular makeup of the offspring of a dividing cell gradually becomes phenotypically decorrelated from the parent cell by noise and regulatory mechanisms that amplify phenotypic heterogeneity. Such regulatory mechanisms form networks that contain thresholds between phenotypes. Populations of cells can be poised near the threshold so that a subset of the population probabilistically undergoes the phenotypic transition. We sought to characterize the diversity of bacterial populations around a growth-modulating threshold via analysis of the effect of non-genetic inheritance, similar to conditions that create antibiotic-tolerant persister cells and other examples of bet hedging. Using simulations and experimental lineage data in Escherichia coli, we present evidence that regulation of growth amplifies the dependence of growth arrest on cellular lineage, causing clusters of related cells undergo growth arrest in certain conditions. Our simulations predict that lineage correlations and the sensitivity of growth to changes in toxin levels coincide in a critical regime. Below the critical regime, the sizes of related growth arrested clusters are distributed exponentially, while in the critical regime clusters sizes are more likely to become large. Furthermore, phenotypic diversity can be nearly as high as possible near the critical regime, but for most parameter values it falls far below the theoretical limit. We conclude that lineage information is indispensable for understanding regulation of cellular growth.


Assuntos
Processos de Crescimento Celular/fisiologia , Proliferação de Células/fisiologia , Antibacterianos/farmacologia , Bactérias/genética , Bactérias/metabolismo , Fenômenos Fisiológicos Bacterianos/genética , Simulação por Computador , Escherichia coli/genética , Escherichia coli/fisiologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/fisiologia , Redes Reguladoras de Genes/genética , Modelos Genéticos , Fenótipo
16.
Front Pharmacol ; 9: 592, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29922165

RESUMO

Background: We recently identified the balance between the level of G protein coupled receptor kinase 2 (GRK2) and Epac1 in nociceptors as a key factor in the transition from acute to chronic pain that occurs in mice 'primed' by an inflammatory stimulus. Here, we examined the contribution of GRK2 and Epac-signaling to growth factor-induced hyperalgesic priming. Methods: Mice were primed by intraplantar injection with glial cell-derived neurotrophic factor (GDNF). Mechanical allodynia in response to PGE2 was followed over time in primed and non-primed animals. GRK2 protein levels in dorsal root ganglion (DRG) neurons were quantified by immunohistochemistry. The effect of herpes simplex virus (HSV)-GRK2 amplicons to restore GRK2 levels or of an Epac inhibitor on PGE2 allodynia in primed mice was examined. Results: Glial cell-derived neurotrophic factor-induced hyperalgesia disappeared within 12 days. The hyperalgesic response to a subsequent intraplantar injection of PGE2 was prolonged from <24 h in control mice to more than 72 h in GDNF-primed mice. In male and female primed mice, PGE2 hyperalgesia was inhibited by oral administration of the Epac inhibitor ESI-09, while the drug had no effect in control mice. Mice primed with GDNF had reduced levels of GRK2 in IB4(+) small DRG neurons, but normal GRK2 levels in IB4(-) DRG neurons. Intraplantar administration of HSV-GRK2 amplicons to increase GRK2 protein levels prevented the prolongation of PGE2-induced hyperalgesia in GDNF-primed mice. Conclusion: Low GRK2 in nociceptors is critical to develop a primed state in response to GDNF and leads to engagement of Epac signaling and transition to chronic PGE2-induced hyperalgesia. Increasing GRK2 protein or inhibiting Epac signaling may represent new avenues for preventing transition to a chronic pain state.

17.
Front Microbiol ; 8: 2425, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29270164

RESUMO

Hepatitis B virus (HBV) infection is endemic in Asia and chronic hepatitis B (CHB) is a major public health issue worldwide. Current treatment strategies for CHB are not satisfactory as they induce a low rate of hepatitis B surface antigen (HBsAg) loss. Extracts were prepared from lettuce hydroponically cultivated in solutions containing glycine or nitrate as nitrogen sources. The lettuce extracts exerted potent anti-HBV effects in HepG2 cell lines in vitro, including significant HBsAg inhibition, HBV replication and transcription inhibition, without exerting cytotoxic effects. When used in combination interferon-alpha 2b (IFNα-2b) or lamivudine (3TC), the lettuce extracts synergistically inhibited HBsAg expression and HBV replication. By using differential metabolomics analysis, Luteolin-7-O-glucoside was identified and confirmed as a functional component of the lettuce extracts and exhibited similar anti-HBV activity as the lettuce extracts in vitro. The inhibition rate on HBsAg was up to 77.4%. Moreover, both the lettuce extracts and luteolin-7-O-glucoside functioned as organic antioxidants and, significantly attenuated HBV-induced intracellular reactive oxygen species (ROS) accumulation. Luteolin-7-O-glucoside also normalized ROS-induced mitochondrial membrane potential damage, which suggests luteolin-7-O-glucoside inhibits HBsAg and HBV replication via a mechanism involving the mitochondria. Our findings suggest luteolin-7-O-glucoside may have potential value for clinical application in CHB and may enhance HBsAg and HBV clearance when used as a combination therapy.

18.
J Am Chem Soc ; 139(36): 12410-12413, 2017 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-28841373

RESUMO

DNA nanostructures assembled on living cell membranes have become powerful research tools. Synthetic lipid membranes have been used as a membrane model to study the dynamic behavior of DNA nanostructures on fluid soft lipid bilayers, but without the inherent complexity of natural membranes. Herein, we report the assembly and disassembly of DNA nanoprisms on cell-mimicking micrometer-scale giant membrane vesicles derived from living mammalian cells. Three-dimensional DNA nanoprisms with a DNA arm and a cholesterol anchor were efficiently localized on the membrane surface. The assembly and disassembly of DNA nanoprisms were dynamically manipulated by DNA strand hybridization and toehold-mediated strand displacement. Furthermore, the heterogeneity of reversible assembly/disassembly of DNA nanoprisms was monitored by Förster resonance energy transfer. This study suggests the feasibility of DNA-mediated functional biomolecular assembly on cell membranes for biomimetics studies and delivery systems.


Assuntos
DNA/química , Nanoestruturas , Conformação de Ácido Nucleico , Animais , Transferência Ressonante de Energia de Fluorescência , Bicamadas Lipídicas
19.
Phys Biol ; 14(4): 045007, 2017 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-28597843

RESUMO

Single cells can stochastically switch across thresholds imposed by regulatory networks. Such thresholds can act as a tipping point, drastically changing global phenotypic states. In ecology and economics, imminent transitions across such tipping points can be predicted using dynamical early warning indicators. A typical example is 'flickering' of a fast variable, predicting a longer-lasting switch from a low to a high state or vice versa. Considering the different timescales between metabolite and protein fluctuations in bacteria, we hypothesized that metabolic early warning indicators predict imminent transitions across a network threshold caused by enzyme saturation. We used stochastic simulations to determine if flickering predicts phenotypic transitions, accounting for a variety of molecular physiological parameters, including enzyme affinity, burstiness of enzyme gene expression, homeostatic feedback, and rates of metabolic precursor influx. In most cases, we found that metabolic flickering rates are robustly peaked near the enzyme saturation threshold. The degree of fluctuation was amplified by product inhibition of the enzyme. We conclude that sensitivity to flickering in fast variables may be a possible natural or synthetic strategy to prepare physiological states for an imminent transition.


Assuntos
Fenômenos Fisiológicos Bacterianos , Modelos Biológicos , Fenótipo , Fenômenos Fisiológicos Bacterianos/genética , Simulação por Computador , Retroalimentação , Expressão Gênica , Processos Estocásticos
20.
ACS Appl Mater Interfaces ; 9(7): 5847-5854, 2017 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-28124556

RESUMO

Multifunctional synergistic therapy holds promise in biomedical studies and clinical practice. However, strategies aimed at easily integrating the components of such multimodal therapies are needed. Therefore, we herein report a smart drug release nanosystem able to perform photodynamic therapy, photothermal therapy and chemotherapy in a photocontrollable manner. Doxorubicin (DOX), a chemotherapy drug, and 5, 10, 15, 20-tetrakis (1-methylpyridinium-4-yl) porphyrin (TMPyP4), a photosensitizer, were physically intercalated into a DNA assembly immobilized on gold nanorods. The drugs were efficiently delivered to target cells and released under light irradiation, resulting in a synergism that combined phototherapy and chemotherapy for cancer treatment. This smart, photocontrollable drug release nanosystem promises precisely controlled drug release for multifunctional synergistic cancer therapy.


Assuntos
Liberação Controlada de Fármacos , Doxorrubicina , Ouro , Nanotubos , Fototerapia
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