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1.
Clin Appl Thromb Hemost ; 30: 10760296241238010, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38449088

RESUMO

Sepsis is a disorder of host response caused by severe infection that can lead to life-threatening organ dysfunction. There is no specific treatment for sepsis. Although there are many different pathogens that can cause sepsis, endothelial dysfunction is a frequent mechanism resulting in vascular leakage and coagulation problem. Recent studies on the regulatory pathways of vascular endothelium have shown that the disturbance of angiopoietin (Ang) /Tie2 axis can induce endothelial cell activation, which is the core pathogenesis of sepsis. In this review, we aim to discuss the regulation of Ang/Tie2 axis and the biomarkers involved in the context of sepsis. Also, we attempt to explore the prospective and feasibility of Ang/Tie2 axis as a potential target for sepsis intervention to improve clinical outcomes.


Assuntos
Sepse , Humanos , Estudos Prospectivos , Sepse/tratamento farmacológico , Angiopoietinas , Coagulação Sanguínea , Endotélio Vascular
2.
J Am Chem Soc ; 146(11): 7498-7505, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38465595

RESUMO

Biology achieves remarkable function through processes arising from spontaneous or transient liquid-liquid phase separation (LLPS) of proteins and other biomolecules. While polymeric systems can achieve similar phenomena through simple or complex coacervation, LLPS with supramolecular materials has been less commonly shown. Functional applications for synthetic LLPS systems are an expanding area of emphasis, with particular focus on capturing the transient and dynamic state of these structures for use in biomedicine. Here, a net-cationic supramolecular peptide amphiphile building block with a glucose-binding motif is shown that forms LLPS structures when combined with a net-negatively charged therapeutic protein, dasiglucagon, in the presence of glucose. The droplets that arise are dynamic and coalesce quickly. However, the interface can be stabilized by addition of a 4-arm star PEG. When the stabilized droplets formed in glucose are transferred to a bulk phase containing different glucose concentrations, their stability and lifetime decrease according to bulk glucose concentration. This glucose-dependent formation translates into an accelerated release of dasiglucagon in the absence of glucose; this hormone analogue itself functions therapeutically to correct low blood glucose (hypoglycemia). These droplets also offer function in mitigating the most severe effects of hypoglycemia arising from an insulin overdose through delivery of dasiglucagon in a mouse model of hypoglycemic rescue. Accordingly, this approach to use complexation between a supramolecular peptide amphiphile and a therapeutic protein in the presence of glucose leads to droplets with functional potential to dissipate for the release of the therapeutic material in low blood glucose environments.


Assuntos
Glicemia , Hipoglicemia , Animais , Camundongos , Glucose , Hipoglicemia/tratamento farmacológico , Hipoglicemia/metabolismo , Proteínas , Polímeros
3.
Adv Mater ; : e2311498, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38095904

RESUMO

Peptide self-assembly is a powerful tool to prepare functional materials at the nanoscale. Often, the resulting materials have high aspect-ratio, with intermolecular ß-sheet formation underlying 1D fibrillar structures. Inspired by dynamic structures in nature, peptide self-assembly is increasingly moving toward stimuli-responsive designs wherein assembled structures are formed, altered, or dissipated in response to a specific cue. Here, a peptide bearing a prosthetic glucose-binding phenylboronic acid (PBA) is demonstrated to self-assemble into an uncommon nanocoil morphology. These nanocoils arise from antiparallel ß-sheets, with molecules aligned parallel to the long axis of the coil. The binding of glucose to the PBA motif stabilizes and elongates the nanocoil, driving entanglement and gelation at physiological glucose levels. The glucose-dependent gelation of these materials is then explored for the encapsulation and release of a therapeutic agent, glucagon, that corrects low blood glucose levels. Accordingly, the release of glucagon from the nanocoil hydrogels is inversely related to glucose level. When evaluated in a mouse model of severe acute hypoglycemia, glucagon delivered from glucose-stabilized nanocoil hydrogels demonstrates increased protection compared to delivery of the agent alone or within a control nanocoil hydrogel that is not stabilized by glucose.

4.
Elife ; 122023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38126335

RESUMO

The discovery of a new neurotransmitter, especially one in the central nervous system, is both important and difficult. We have been searching for new neurotransmitters for 12 y. We detected creatine (Cr) in synaptic vesicles (SVs) at a level lower than glutamate and gamma-aminobutyric acid but higher than acetylcholine and 5-hydroxytryptamine. SV Cr was reduced in mice lacking either arginine:glycine amidinotransferase (a Cr synthetase) or SLC6A8, a Cr transporter with mutations among the most common causes of intellectual disability in men. Calcium-dependent release of Cr was detected after stimulation in brain slices. Cr release was reduced in Slc6a8 and Agat mutants. Cr inhibited neocortical pyramidal neurons. SLC6A8 was necessary for Cr uptake into synaptosomes. Cr was found by us to be taken up into SVs in an ATP-dependent manner. Our biochemical, chemical, genetic, and electrophysiological results are consistent with the possibility of Cr as a neurotransmitter, though not yet reaching the level of proof for the now classic transmitters. Our novel approach to discover neurotransmitters is to begin with analysis of contents in SVs before defining their function and physiology.


Assuntos
Creatina , Deficiência Intelectual , Masculino , Humanos , Camundongos , Animais , Creatina/genética , Deficiência Intelectual/genética , Sistema Nervoso Central , Neurotransmissores , Eletrofisiologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-37937557

RESUMO

BACKGROUND: Stem cell properties vary considerably based on the source and tissue site of mesenchymal stem cells (MSCs). The mandibular condyle is a unique kind of craniofacial bone with a special structure and a relatively high remodeling rate. MSCs here may also be unique to address specific physical needs. OBJECTIVE: The aim of this study was to compare the proliferation and multidirectional differentiation potential among MSCs derived from the tibia (TMSCs), mandibular ramus marrow (MMSCs), and condylar subchondral bone (SMSCs) of rats in vitro. METHODS: Cell proliferation and migration were assessed by CCK-8, laser confocal, and cell scratch assays. Histochemical staining and real-time PCR were used to evaluate the multidirectional differentiation potential and DNA methylation and histone deacetylation levels. RESULTS: The proliferation rate and self-renewal capacity of SMSCs were significantly higher than those of MMSCs and TMSCs. Moreover, SMSCs possessed significantly higher mineralization and osteogenic differentiation potential. Dnmt2, Dnmt3b, Hdac6, Hdac7, Hdac9, and Hdac10 may be instrumental in the osteogenesis of SMSCs. In addition, SMSCs are distinct from MMSCs and TMSCs with lower adipogenic differentiation and chondrogenic differentiation potential. The multidirectional differentiation capacities of TMSCs were exactly the opposite of those of SMSCs, and the results of MMSCs were intermediate. CONCLUSION: This research offers a new paradigm in which SMSCs could be a useful source of stem cells for further application in stem cell-based medical therapies due to their strong cell renewal and osteogenic capacity.

6.
Elife ; 122023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37440432

RESUMO

Human mutations in the gene encoding the solute carrier (SLC) 6A17 caused intellectual disability (ID). The physiological role of SLC6A17 and pathogenesis of SLC6A17-based-ID were both unclear. Here, we report learning deficits in Slc6a17 knockout and point mutant mice. Biochemistry, proteomic, and electron microscopy (EM) support SLC6A17 protein localization in synaptic vesicles (SVs). Chemical analysis of SVs by liquid chromatography coupled to mass spectrometry (LC-MS) revealed glutamine (Gln) in SVs containing SLC6A17. Virally mediated overexpression of SLC6A17 increased Gln in SVs. Either genetic or virally mediated targeting of Slc6a17 reduced Gln in SVs. One ID mutation caused SLC6A17 mislocalization while the other caused defective Gln transport. Multidisciplinary approaches with seven types of genetically modified mice have shown Gln as an endogenous substrate of SLC6A17, uncovered Gln as a new molecule in SVs, established the necessary and sufficient roles of SLC6A17 in Gln transport into SVs, and suggested SV Gln decrease as the key pathogenetic mechanism in human ID.


Assuntos
Deficiência Intelectual , Vesículas Sinápticas , Animais , Camundongos , Glutamina/metabolismo , Deficiência Intelectual/genética , Deficiência Intelectual/metabolismo , Mutação , Proteômica , Vesículas Sinápticas/metabolismo
7.
World J Microbiol Biotechnol ; 39(10): 262, 2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37507604

RESUMO

Tellurium is a super-trace metalloid on Earth. Owing to its excellent physical and chemical properties, it is used in industries such as metallurgy and manufacturing, particularly of semiconductors and - more recently - solar panels. As the global demand for tellurium rises, environmental issues surrounding tellurium have recently aroused concern due to its high toxicity. The amount of tellurium released to the environment is increasing, and microorganisms play an important role in the biogeochemical cycling of environmental tellurium. This review focuses on novel developments on tellurium transformations driven by microbes and includes the following sections: (1) history and applications of tellurium; (2) toxicity of tellurium; (3) microbial detoxification mechanisms against soluble tellurium anions including uptake, efflux and methods of reduction, and reduced ability to cope with oxidation stress or repair damaged DNA; and (4) the characteristics and applications of tellurium nanoparticles (TeNPs) produced by microbes. This review raises the awareness of microorganisms in tellurium biogeochemical cycling and the growing applications for microbial tellurium nanoparticles.


Assuntos
Nanopartículas , Oligoelementos , Telúrio/química
8.
BMC Oral Health ; 23(1): 209, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041485

RESUMO

BACKGROUND: The dentinogenesis differentiation of dental pulp stem cells (DPSCs) is controlled by the spatio-temporal expression of differentiation related genes. RNA N6-methyladenosine (m6A) methylation, one of the most abundant internal epigenetic modification in mRNA, influences various events in RNA processing, stem cell pluripotency and differentiation. Methyltransferase like 3 (METTL3), one of the essential regulators, involves in the process of dentin formation and root development, while mechanism of METTL3-mediated RNA m6A methylation in DPSC dentinogenesis differentiation is still unclear. METHODS: Immunofluorescence staining and MeRIP-seq were performed to establish m6A modification profile in dentinogenesis differentiation. Lentivirus were used to knockdown or overexpression of METTL3. The dentinogenesis differentiation was analyzed by alkaline phosphatase, alizarin red staining and real time RT-PCR. RNA stability assay was determined by actinomycin D. A direct pulp capping model was established with rat molars to reveal the role of METTL3 in tertiary dentin formation. RESULTS: Dynamic characteristics of RNA m6A methylation in dentinogenesis differentiation were demonstrated by MeRIP-seq. Methyltransferases (METTL3 and METTL14) and demethylases (FTO and ALKBH5) were gradually up-regulated during dentinogenesis process. Methyltransferase METTL3 was selected for further study. Knockdown of METTL3 impaired the DPSCs dentinogenesis differentiation, and overexpression of METTL3 promoted the differentiation. METTL3-mediated m6A regulated the mRNA stabiliy of GDF6 and STC1. Furthermore, overexpression of METTL3 promoted tertiary dentin formation in direct pulp capping model. CONCLUSION: The modification of m6A showed dynamic characteristics during DPSCs dentinogenesis differentiation. METTL3-mediated m6A regulated in dentinogenesis differentiation through affecting the mRNA stability of GDF6 and STC1. METTL3 overexpression promoted tertiary dentin formation in vitro, suggesting its promising application in vital pulp therapy (VPT).


Assuntos
Polpa Dentária , Dentinogênese , Animais , Ratos , Diferenciação Celular , Metiltransferases/genética , Metiltransferases/metabolismo , RNA/metabolismo , Estabilidade de RNA , RNA Mensageiro/metabolismo , Células-Tronco/metabolismo
9.
ACS Biomater Sci Eng ; 8(11): 4873-4885, 2022 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-36317822

RESUMO

Stimuli-responsive hydrogels are an area of active discovery for approaches to deliver therapeutics in response to disease-specific indicators. Glucose-responsive delivery of insulin is of particular interest in better managing diabetes. Accordingly, hydrogels have been explored as platforms that enable both a rate and dose of insulin release aligning with the real-time physiological disease state; materials often include glucose sensing by dynamic-covalent cross-linking between phenylboronic acids (PBAs) and diols, with competition from ambient glucose reducing cross-link density of the material and accelerating release of encapsulated insulin. Yet, these materials historically have challenges with insulin leakage, offer limited glucose-responsive release of the insulin payload, and require unreasonably high injection pressures for syringe administration. Here, a thermogel platform prepared from temperature-induced micelles formed into a network by PBA-Diol cross-linking is optimized using a formulation-centered approach to maximize glucose-responsive insulin delivery. Importantly, the dual-responsive nature of this platform enables a low-viscosity sol at ambient temperature for facile injection, solidifying into a stable viscoelastic hydrogel network once in the body. The final optimized formulation affords acceleration in insulin release in response to glucose and enables single dose blood glucose control in diabetic rodents when subjected to multiple glucose challenges.


Assuntos
Micelas , Poloxâmero , Glucose , Hidrogéis , Insulina/farmacologia
10.
World J Stem Cells ; 14(7): 490-502, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-36157525

RESUMO

Stem cell fate determination is one of the central questions in stem cell biology, and although its regulation has been studied at genomic and proteomic levels, a variety of biological activities in cells occur at the metabolic level. Metabolomics studies have established the metabolome during stem cell differentiation and have revealed the role of metabolites in stem cell fate determination. While metabolism is considered to play a biological regulatory role as an energy source, recent studies have suggested the nexus between metabolism and epigenetics because several metabolites function as cofactors and substrates in epigenetic mechanisms, including histone modification, DNA methylation, and microRNAs. Additionally, the epigenetic modification is sensitive to the dynamic metabolites and consequently leads to changes in transcription. The nexus between metabolism and epigenetics proposes a novel stem cell-based therapeutic strategy through manipulating metabolites. In the present review, we summarize the possible nexus between metabolic and epigenetic regulation in stem cell fate determination, and discuss the potential preventive and therapeutic strategies via targeting metabolites.

11.
Biomacromolecules ; 23(10): 4401-4411, 2022 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-36173091

RESUMO

The ongoing rise in diabetes incidence necessitates improved therapeutic strategies to enable precise blood glucose control with convenient device form factors. Microneedle patches are one such device platform capable of achieving therapeutic delivery through the skin. In recent years, polymeric microneedle arrays have been reported using methods of in situ polymerization and covalent crosslinking in microneedle molds. In spite of promising results, in situ polymerization carries a risk of exposure to toxic unreacted precursors remaining in the device. Here, a polymeric microneedle patch is demonstrated that uses dynamic-covalent phenylboronic acid (PBA)-diol bonds in a dual role affording both network crosslinking and glucose sensing. By this approach, a pre-synthesized and purified polymer bearing pendant PBA motifs is combined with a multivalent diol crosslinker to prepare dynamic-covalent hydrogel networks. The ability of these dynamic hydrogels to shear-thin and self-heal enables their loading to a microneedle mold by centrifugation. Subsequent drying then yields a patch of uniformly shaped microneedles with the requisite mechanical properties to penetrate skin. Insulin release from these materials is accelerated in the presence of glucose. Moreover, short-term blood glucose control in a diabetic rat model following application of the device to the skin confirms insulin activity and bioavailability. Accordingly, dynamic-covalent crosslinking facilitates a route for fabricating microneedle arrays circumventing the toxicity concerns of in situ polymerization, offering a convenient device form factor for therapeutic insulin delivery.


Assuntos
Diabetes Mellitus , Insulina , Administração Cutânea , Animais , Sistemas de Liberação de Medicamentos/métodos , Glucose , Hidrogéis , Insulina/química , Agulhas , Polímeros/química , Ratos
12.
PLoS One ; 17(7): e0271738, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35862412

RESUMO

INTRODUCTION: At present, the possible relationship between obstructive sleep apnea and periodontitis has been reported. The link remains ambiguous and unclear. The objective of this study is to assess the association between OSA and periodontitis. METHODS: Three databases, including Pubmed, Embase, and the Web of Science, were systematically searched to identify eligible studies that from their establishment to February 2022 for relevant studies. Subsequently, a meta-analysis was conducted to determine the relationship of pooled-effects more accurately. RESULTS: A summary analysis of the 9 results from the studies covering 43,414 individuals showed a statistical association results of the between OSA and the incidence rate of periodontitis(OR = 0.52; 95% CI: 0.49-0.55; I2 = 98.43%; P = 0.000). In addition, OSA patients and the risk of the population were statistically significantly associated with an increased risk of periodontitis.(OR = 1.56; 95% CI: 1.06-2.06; P = 0.00). CONCLUSIONS: Our results indicated that OSA may be associated with an increased risk of periodontitis. Further studies are required to confirm the link and explore the underlying mechanism of the link.


Assuntos
Periodontite , Apneia Obstrutiva do Sono , Bases de Dados Factuais , Humanos , Incidência , Periodontite/complicações , Periodontite/epidemiologia , Fatores de Risco , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/epidemiologia
13.
BMC Pulm Med ; 22(1): 238, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729588

RESUMO

BACKGROUND: Less is known about the risk factors for acute respiratory distress syndrome (ARDS) in sepsis patients diagnosed according to sepsis 3.0 criteria. Moreover, the risk factors for ARDS severity remain unclear. METHODS: We retrospectively collected the characteristics of sepsis patients from the intensive care unit of the First Affiliated Hospital of China Medical University from January 2017 to September 2018. Logistic regression was used in determining the risk factors. RESULTS: 529 patients with sepsis were enrolled and 179 developed ARDS. The most common infection sites were acute abdominal infection (n = 304) and pneumonia (n = 117). Multivariate analysis showed that patients with pancreatitis with local infection (odds ratio [OR], 3.601; 95% confidence interval [CI], 1.429-9.073, P = 0.007), pneumonia (OR 3.486; 95% CI 1.890-6.430, P < 0.001), septic shock (OR 2.163; 95% CI 1.429-3.275, P < 0.001), a higher sequential organ failure assessment (SOFA) score (OR 1.241; 95% CI 1.155-1.333, P < 0.001) and non-pulmonary SOFA score (OR 2.849; 95% CI 2.113-3.841, P < 0.001) were independent risk factors for ARDS. Moreover, pneumonia is associated with increased severity of ARDS (OR 2.512; 95% CI 1.039-6.067, P = 0.041). CONCLUSIONS: We determined five risk factors for ARDS in sepsis patients. Moreover, pneumonia is significantly associated with an increased severity of ARDS.


Assuntos
Síndrome do Desconforto Respiratório , Sepse , Humanos , Unidades de Terapia Intensiva , Prognóstico , Síndrome do Desconforto Respiratório/epidemiologia , Síndrome do Desconforto Respiratório/etiologia , Estudos Retrospectivos , Fatores de Risco , Sepse/complicações , Sepse/epidemiologia , Centros de Atenção Terciária
14.
J Control Release ; 348: 601-611, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35714732

RESUMO

Dynamic-covalent motifs are increasingly used for hydrogel crosslinking, leveraging equilibrium-governed reversible bonds to prepare viscoelastic materials with dynamic properties and self-healing character. The bonding between aryl boronates and diols is one dynamic-covalent chemistry of interest. The extent of network crosslinking using this motif may be subject to competition from ambient diols such as glucose; this approach has long been explored for glucose-directed release of insulin to control diabetes. However, the majority of such work has used phenylboronic acids (PBAs) that suffer from low-affinity glucose binding, limiting material responsiveness. Moreover, many PBA chemistries also bind with higher affinity to certain non-glucose analytes like fructose and lactate than they do to glucose, limiting their specificity of sensing and therapeutic deployment. Here, dynamic-covalent hydrogels are prepared that, for the first time, use a new diboronate motif with enhanced glucose binding-and importantly improved glucose specificity-leveraging the ability of rigid diboronates to simultaneously bind two sites on a single glucose molecule. Compared to long-used PBA-based approaches, diboronate hydrogels offer more glucose-responsive insulin release that is minimally impacted by non-glucose analytes. Improved responsiveness translates to more rapid blood glucose correction in a rodent diabetes model. Accordingly, this new dynamic-covalent crosslinking chemistry is useful in realizing more sensitive and specific glucose-responsive materials.


Assuntos
Glucose , Hidrogéis , Glucose/química , Hidrogéis/química , Insulina/química
16.
Int J Hematol ; 116(1): 48-54, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35380387

RESUMO

Coagulation disorders ranging from subtle changes in coagulation parameters to fatal disseminated intravascular coagulation (DIC) are common in septic patients. Coagulation activation is considered to be one of the most important factors contributing to multiple organ dysfunction syndrome (MODS) in sepsis. Anticoagulant therapy is, therefore, necessary to prevent MODS, but eligibility criteria remain controversial. Sepsis is a highly heterogeneous syndrome, which could explain the negative results of clinical studies on the treatment of sepsis. Recently, sepsis has been subdivided into several phenotypes with different therapeutic outcomes. At present, septic patients with dysfunctional coagulation expressed as increased D-dimer and fibrin/fibrinogen degradation products (FDPs) are considered to be candidates for anticoagulant therapy. In this review, we aimed to describe the features of different septic phenotypes. We also discuss factors that contribute to controversies in this area, and challenges in defining which septic phenotypes are good candidates for anticoagulant therapy.


Assuntos
Coagulação Intravascular Disseminada , Sepse , Anticoagulantes/uso terapêutico , Coagulação Intravascular Disseminada/tratamento farmacológico , Coagulação Intravascular Disseminada/etiologia , Humanos , Insuficiência de Múltiplos Órgãos/tratamento farmacológico , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/prevenção & controle , Fenótipo , Sepse/tratamento farmacológico , Sepse/etiologia
17.
BMC Anesthesiol ; 22(1): 28, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-35062871

RESUMO

BACKGROUND: The anticoagulant treatment and clinical efficacy of heparin in sepsis remains controversial. We conducted a meta-analysis to estimate the clinical efficacy of unfractionated heparin (UFH) in adult septic patients. METHOD: A systematic review of Medline, Cochrane Library, PubMed, Embase, WEIPU database, CNKI database, WANFANG database was performed from inception to January 2021. We included Randomized controlled trials (RCTs) and the main outcome was 28 d mortality. Data analysis was performed with Review Manager (RevMan) version 5.3 software. The meta-analysis included 2617 patients from 15 RCTs. RESULTS: Comparing to control group, UFH could reduce 28 d mortality (RR: 0.82; 95% CI: 0.72 to 0.94) especially for patient with Acute Physiology and Chronic Health Evaluation II (APACHE II) > 15, (RR: 0.83; 95% CI: 0.72 to 0.96). In UFH group, the platelet (PLT) (MD: 9.18; 95% CI: 0.68 to 17.68) was higher, the activated partial thromboplastin time (APTT) was shorter (MD: -8.01; 95% CI: - 13.84 to - 2.18) and the prothrombin time (PT) results (P > 0.05) failed to reach statistical significance. UFH decreased multiple organ dysfunction syndrome (MODS) incidence (RR: 0.61; 95% CI: 0.45 to 0.84), length of stay (LOS) in ICU (MD: -4.94; 95% CI: - 6.89 to - 2.99) and ventilation time (MD: -3.01; 95% CI: - 4.0 to - 2.02). And UFH had no adverse impact on bleeding (RR: 1.10; 95% CI: 0.54 to 2.23). CONCLUSION: This meta-analysis suggests that UFH may reduce 28 d mortality and improve the clinical efficacy in sepsis patients without bleeding adverse effect.


Assuntos
Anticoagulantes/uso terapêutico , Heparina/uso terapêutico , Sepse/tratamento farmacológico , Adulto , Humanos , Resultado do Tratamento
18.
Inflammation ; 45(2): 712-724, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34657233

RESUMO

Endothelial glycocalyx degradation is thought to facilitate the development of sepsis. Histone is a significant mediator in sepsis. Unfractionated heparin (UFH) possessed beneficial effects on sepsis. Thereby, this study aims to figure out whether histone can disrupt glycocalyx and to investigate the protective effect and mechanism of UFH. Male mice (C57BL/6, 8-10 weeks old, weighing 20-25 g) were randomly divided into five groups including control group, histone group, histone + UFH group, histone + heparinase (HPA) inhibitor group, and histone + UFH + HPA inhibitor group. The mice were treated with histone (50 mg/kg) via tail vein immediately after HPA (20 mg/kg) injection. UFH (400 U/kg) was injected 1h after histone administration. The other groups were injected with equal volume of sterile saline accordingly. UFH alleviated histone-induced lung injury and pulmonary edema. UFH inhibited histone-induced lung coagulation activation and inflammatory response. UFH treatment markedly inhibited pulmonary glycocalyx degradation by reducing the histone-induced decrease in the levels of lung syndecan-1 mRNA and protein. UFH downregulated histone-induced expression of HPA mRNA and protein, and thus alleviated glycocalyx degradation. UFH protects against histone-induced pulmonary glycocalyx injury partly by heparinase pathway.


Assuntos
Heparina , Histonas , Animais , Heparina/farmacologia , Heparina/uso terapêutico , Heparina Liase/farmacologia , Histonas/farmacologia , Pulmão , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sindecana-1
19.
World J Stem Cells ; 13(11): 1647-1666, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34909116

RESUMO

Regenerative endodontics (RE) therapy means physiologically replacing damaged pulp tissue and regaining functional dentin-pulp complex. Current clinical RE procedures recruit endogenous stem cells from the apical papilla, periodontal tissue, bone marrow and peripheral blood, with or without application of scaffolds and growth factors in the root canal space, resulting in cementum-like and bone-like tissue formation. Without the involvement of dental pulp stem cells (DPSCs), it is unlikely that functional pulp regeneration can be achieved, even though acceptable repair can be acquired. DPSCs, due to their specific odontogenic potential, high proliferation, neurovascular property, and easy accessibility, are considered as the most eligible cell source for dentin-pulp regeneration. The regenerative potential of DPSCs has been demonstrated by recent clinical progress. DPSC transplantation following pulpectomy has successfully reconstructed neurovascularized pulp that simulates the physiological structure of natural pulp. The self-renewal, proliferation, and odontogenic differentiation of DPSCs are under the control of a cascade of transcription factors. Over recent decades, epigenetic modulations implicating histone modifications, DNA methylation, and noncoding (nc)RNAs have manifested as a new layer of gene regulation. These modulations exhibit a profound effect on the cellular activities of DPSCs. In this review, we offer an overview about epigenetic regulation of the fate of DPSCs; in particular, on the proliferation, odontogenic differentiation, angiogenesis, and neurogenesis. We emphasize recent discoveries of epigenetic molecules that can alter DPSC status and promote pulp regeneration through manipulation over epigenetic profiles.

20.
ACS Appl Mater Interfaces ; 13(37): 44147-44156, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34515459

RESUMO

Immobilization of proteins on magnetic nanoparticles (MNPs) is an effective approach to improve protein stability and facilitate separation of immobilized proteins for repeated use. Herein, we exploited the efficient SpyTag-SpyCatcher chemistry for conjugation of functional proteins onto MNPs and established a robust magnetic-responsive nanoparticle platform for protein immobilization. To maximize the loading capacity and achieve outstanding water dispersity, the SpyTag peptide was incorporated into the surface-charged polymers of MNPs, which provided abundant active sites for Spy chemistry while maintaining excellent colloidal stability in buffer solution. Conjugation between enhanced green fluorescence protein (EGFP)-SpyCatcher-fused proteins and SpyTag-functionalized MNPs was efficient at ambient conditions without adding enzymes or chemical cross-linkers. Benefiting from the excellent water dispersity and interface compatibility, the surface Spy reaction has fast kinetics, which is comparable to that of the solution Spy reaction. No activity loss was observed on EGFP after conjugation due to the site-selective nature of Spy chemistry. The immobilization process of EGFP on MNPs was highly specific and robust, which was not affected by the presence of other proteins and detergents, such as bovine serum albumin and Tween 20. The MNP platform was demonstrated to be protective to the conjugated EGFP and significantly improved the shelf life of immobilized proteins. In addition, experiments confirmed the retained magnetophoresis of the MNP after protein loading, demonstrating fast MNP recovery under an external magnetic field. This MNP is expected to provide a versatile and modular platform to achieve effective and specific immobilization of other functional proteins, enabling easy reuse and storage.


Assuntos
Proteínas de Fluorescência Verde/química , Proteínas Imobilizadas/química , Nanopartículas de Magnetita/química , Sequência de Aminoácidos , Fenômenos Magnéticos , Metacrilatos/química , Nylons/química , Peptídeos/química , Dióxido de Silício/química
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