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1.
Pestic Biochem Physiol ; 171: 104697, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357538

RESUMO

Glycoprotein (GP)-1 is a glycoprotein elicitor with antiviral activity found in Streptomyces kanasensis zx01. GP-1 can induce programmed cell death (PCD) in vitro; however, the underlying mechanism is unclear. In the present study, we demonstrated that GP-1 induced PCD in tobacco suspension cells, which was modulated by hydrogen peroxide (H2O2). GP-1 participated in and modulated biologically relevant signaling in plant cells. GP-1 induced tobacco cell death in a dose- and time-dependent manner; affected the expression of BRI1-associated receptor kinase 1 (BAK1) and the accumulation of salicylic acid (SA), which are related to PCD; and enzymatic activities and mitochondrial functions. In conclusion, GP-1-induced PCD in tobacco may be mediated by H2O2 which alters BAK1 and SA levels, as well as mitochondrial and gene function. This cell signal cascade played an important role in the process of GP-1 induced plant disease resistance.


Assuntos
Peróxido de Hidrogênio , Nicotiana , Apoptose , Glicoproteínas , Streptomyces
2.
Anal Biochem ; 553: 7-11, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29777679

RESUMO

Listeria monocytogenes is an important foodborne pathogen, and it can cause severe diseases. Rapid detection of L. monocytogenes is crucial to control this pathogen. A simple and robust strategy based on the cascade of PCR and G-quadruplex DNAzyme catalyzed reaction was used to detect L. monocytogenes. In the presence of hemin and the aptamer formed during PCR, the catalytic horseradish peroxidase-mimicking G-quadruplex DNAzymes allow the colorimetric responses of target DNA from L. monocytogenes. This assay can detect genomic DNA of L. monocytogenes specifically with as low as 50 pg/reaction with the naked eye. Through 20 pork samples assay, visual detection assay had the same results as conventional detection methods, and had a good performance. This is a powerful demonstration of the ability of G-quadruplex DNAzyme to be used for PCR-based assay with significant advantages of high sensitivity, low cost and simple manipulation over existing approaches and offers the opportunity for application in pathogen detection.


Assuntos
DNA Catalítico/metabolismo , Microbiologia de Alimentos , Listeria monocytogenes/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Transdução de Sinais , Catálise , Colorimetria/métodos , Peroxidase do Rábano Silvestre/química
3.
Front Neurosci ; 17: 1225191, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37521706

RESUMO

Introduction: Xenon exhibits significant neuroprotection against a wide range of neurological insults in animal models. However, clinical evidence that xenon improves outcomes in human studies of neurological injury remains elusive. Previous reviews of xenon's method of action have not been performed in a systematic manner. The aim of this review is to provide a comprehensive summary of the evidence underlying the cellular interactions responsible for two phenomena associated with xenon administration: anesthesia and neuroprotection. Methods: A systematic review of the preclinical literature was carried out according to the PRISMA guidelines and a review protocol was registered with PROSPERO. The review included both in vitro models of the central nervous system and mammalian in vivo studies. The search was performed on 27th May 2022 in the following databases: Ovid Medline, Ovid Embase, Ovid Emcare, APA PsycInfo, and Web of Science. A risk of bias assessment was performed utilizing the Office of Health Assessment and Translation tool. Given the heterogeneity of the outcome data, a narrative synthesis was performed. Results: The review identified 69 articles describing 638 individual experiments in which a hypothesis was tested regarding the interaction of xenon with cellular targets including: membrane bound proteins, intracellular signaling cascades and transcription factors. Xenon has both common and subtype specific interactions with ionotropic glutamate receptors. Xenon also influences the release of inhibitory neurotransmitters and influences multiple other ligand gated and non-ligand gated membrane bound proteins. The review identified several intracellular signaling pathways and gene transcription factors that are influenced by xenon administration and might contribute to anesthesia and neuroprotection. Discussion: The nature of xenon NMDA receptor antagonism, and its range of additional cellular targets, distinguishes it from other NMDA antagonists such as ketamine and nitrous oxide. This is reflected in the distinct behavioral and electrophysiological characteristics of xenon. Xenon influences multiple overlapping cellular processes, both at the cell membrane and within the cell, that promote cell survival. It is hoped that identification of the underlying cellular targets of xenon might aid the development of potential therapeutics for neurological injury and improve the clinical utilization of xenon. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier: 336871.

4.
Food Chem ; 374: 131586, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-34839969

RESUMO

Various structural types of polysaccharides are recognized by toll-like receptor 4 (TLR4). However, the mechanism of interaction between the polysaccharides with different structures and TLR4 is unclarified. This review summarized the primary structure of polysaccharides related to TLR4, mainly including molecular weight, monosaccharide composition, glycosidic bonds, functional groups, and branched-chain structure. The optimal primary structure for interacting with TLR4 was obtained by the statistical analysis. Besides, the dual-directional regulation of TLR4 signaling cascade by polysaccharides was also elucidated from an immune balance perspective. Finally, the 3D interaction model of polysaccharides to TLR4-myeloid differentiation factor 2 (MD2) complex was hypothesized according to the LPS-TLR4-MD2 dimerization model and the polysaccharides solution conformation. The essence of polysaccharides binding to TLR4-MD2 complex is a multivalent non-covalent bond interaction. All the arguments summarized in this review are intended to provide some new insights into the interaction between polysaccharides and TLR4.


Assuntos
Antígeno 96 de Linfócito , Receptor 4 Toll-Like , Lipopolissacarídeos , Antígeno 96 de Linfócito/metabolismo , Polissacarídeos , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
5.
J Alzheimers Dis ; 85(2): 503-518, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34864675

RESUMO

Specific protein misfolding and aggregation are mechanisms underlying various neurodegenerative diseases such as prion disease and Alzheimer's disease (AD). The misfolded proteins are involved in prions, amyloid-ß (Aß), tau, and α-synuclein disorders; they share common structural, biological, and biochemical characteristics, as well as similar mechanisms of aggregation and self-propagation. Pathological features of AD include the appearance of plaques consisting of deposition of protein Aß and neurofibrillary tangles formed by the hyperphosphorylated tau protein. Although it is not clear how protein aggregation leads to AD, we are learning that the cellular prion protein (PrPC) plays an important role in the pathogenesis of AD. Herein, we first examined the pathogenesis of prion and AD with a focus on the contribution of PrPC to the development of AD. We analyzed the mechanisms that lead to the formation of a high affinity bond between Aß oligomers (AßOs) and PrPC. Also, we studied the role of PrPC as an AßO receptor that initiates an AßO-induced signal cascade involving mGluR5, Fyn, Pyk2, and eEF2K linking Aß and tau pathologies, resulting in the death of neurons in the central nervous system. Finally, we have described how the PrPC-AßOs interaction can be used as a new potential therapeutic target for the treatment of PrPC-dependent AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Proteínas Priônicas/genética , Proteínas Priônicas/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Humanos , Emaranhados Neurofibrilares/patologia , Neurônios/patologia , Agregação Patológica de Proteínas , Ensaios Clínicos Controlados Aleatórios como Assunto , Receptor de Glutamato Metabotrópico 5/metabolismo , alfa-Sinucleína/metabolismo , Proteínas tau/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-34423177

RESUMO

Antibodies are extremely valuable tools in modern medicine due to their ability to target diseased cells through selective antigen binding and thereby regulate cellular signaling or inhibit cell-cell interactions with high specificity. However, the therapeutic utility of freely delivered antibodies is limited by high production costs, low efficacy, dose-limiting toxicities, and inability to cross the cellular membrane (which hinders antibodies against intracellular targets). To overcome these limitations, researchers have begun to develop nanocarriers that can improve antibodies' delivery efficiency, safety profile, and clinical potential. This review summarizes recent advances in the design and implementation of nanocarriers for extracellular or intracellular antibody delivery, emphasizing important design considerations, and points to future directions for the field.

7.
ACS Nano ; 15(8): 13188-13199, 2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34342966

RESUMO

Chemical messengers have been recognized as signaling molecules involved in regulating various physiological and metabolic activities. Nevertheless, they usually show limited regulatory efficiency due to the complexity of biological processes. Especially for tumor cells, antideath pathways and tumor metastasis are readily activated to resist chemical messenger regulation, further impairing antitumor outcomes. Therefore, it is imperative to develop strategies for tumor eradication with chemical messengers. Herein, a nanomessenger was prepared with signaling transduction cascades to amplify the regulatory activity of chemical messengers and mediate antitumor immunotherapy. Ca2+ and H2S as two chemical messengers were released from nanomessengers to synergistically elevate intracellular Ca2+ stress and mediate subsequent cell death. Meanwhile, zinc protoporphyrin (ZnPP) as a messenger amplifier suppressed the antideath effect of tumor cells. As a result, tumor cells underwent Ca2+-dependent cell death via signaling transduction cascades to release tumor-associated antigens, which further served as an in situ tumor vaccine to activate antitumor immunity. In vivo studies revealed that both primary tumors and distant metastases were markedly eradicated. Furthermore, immunological memory was fabricated to arrest tumor metastasis and recurrence. This work introduces cascade engineering into chemical messengers and thus offers a strategy for amplifying chemical messenger-mediated cellular regulation, which would promote the future development of chemical messenger-mediated immunotherapy.̀.


Assuntos
Imunoterapia , Neoplasias , Humanos , Transdução de Sinais , Neoplasias/terapia , Memória Imunológica , Morte Celular , Fatores Imunológicos
8.
ACS Nano ; 14(3): 3378-3388, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32083466

RESUMO

Triple-negative breast cancer (TNBC) accounts for nearly one-quarter of all breast cancer cases, but effective targeted therapies for this disease remain elusive because TNBC cells lack expression of the three most common receptors seen on other subtypes of breast cancer. Here, we exploit TNBC cells' overexpression of Notch-1 receptors and Bcl-2 anti-apoptotic proteins to provide an effective targeted therapy. Prior studies have shown that the small molecule drug ABT-737, which inhibits Bcl-2 to reinstate apoptotic signaling, is a promising candidate for TNBC therapy. However, ABT-737 is poorly soluble in aqueous conditions, and its orally bioavailable derivative causes severe thrombocytopenia. To enable targeted delivery of ABT-737 to TNBC and enhance its therapeutic efficacy, we encapsulated the drug in poly(lactic-co-glycolic acid) nanoparticles (NPs) that were functionalized with Notch-1 antibodies to produce N1-ABT-NPs. The antibodies in this NP platform enable both TNBC cell-specific binding and suppression of Notch signaling within TNBC cells by locking the Notch-1 receptors in a ligand unresponsive state. This Notch inhibition potentiates the effect of ABT-737 by up-regulating Noxa, resulting in effective killing of TNBC cells. We present the results of in vitro studies that demonstrate N1-ABT-NPs can preferentially bind TNBC cells versus noncancerous breast epithelial cells to effectively regulate Bcl-2 and Notch signaling to induce cell death. Further, we show that N1-ABT-NPs can accumulate in subcutaneous TNBC xenograft tumors in mice following systemic administration to reduce tumor burden and extend animal survival. Together, these findings demonstrate that NP-mediated co-delivery of Notch-1 antibodies and ABT-737 is a potent treatment strategy for TNBC that may improve patient outcomes with further development and implementation.


Assuntos
Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Compostos de Bifenilo/farmacologia , Nanopartículas/química , Nitrofenóis/farmacologia , Receptor Notch1/química , Sulfonamidas/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Compostos de Bifenilo/química , Compostos de Bifenilo/metabolismo , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Humanos , Neoplasias Mamárias Experimentais/diagnóstico por imagem , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Camundongos Nus , Nanopartículas/metabolismo , Nitrofenóis/química , Nitrofenóis/metabolismo , Imagem Óptica , Piperazinas/química , Piperazinas/metabolismo , Piperazinas/farmacologia , Receptor Notch1/metabolismo , Sulfonamidas/química , Sulfonamidas/metabolismo , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/metabolismo
9.
Plants (Basel) ; 10(1)2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33375600

RESUMO

The plant kingdom is a rich source of health-promoting compounds and has always played a fundamental role in the isolation, identification, and modification of compounds able to perform several properties on live organisms. Among them, the so-called "antioxidants" have a major potentiality to increase human wellness. Antioxidants are important components in the signaling and defense mechanisms in some plants, where they are precursors of compounds of greater complexity, the modulator of plant growth, and the defensive system against pathogenic organisms and predators. The extraordinary variety of chemical structure and substitution present in the different plant antioxidants make them an inestimable source of interesting compounds, with the ability to counter reactive oxygen/nitrogen species (ROS/RNS) and to stimulate the activation of signal cascade inside the cells. The mechanisms by which antioxidants detoxify these dangerous compounds are complex and involve either direct or indirect interaction with radicals. Antioxidants inhibit or quench free radical reactions mainly based on their reducing capacity or hydrogen atom-donating capacity, their solubility, and chelating properties. Moreover, their ability to modulate key metabolic enzymes and activate/block gene transcription also has remarkable importance.

10.
Mol Ther Nucleic Acids ; 21: 290-298, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32622330

RESUMO

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that lacks expression of the three most common receptors present on other subtypes, leaving it unsusceptible to current targeted or hormonal therapies. In this study, we introduce an alternative treatment strategy for TNBC that exploits its overexpression of Notch1 receptors and its underexpression of the tumor suppressive microRNA (miRNA) miR-34a. Studies have shown that introducing mimics of miR-34a to TNBC cells effectively inhibits cancer growth, but miR-34a cannot be administered in the clinic without a carrier. To enable delivery of miR-34a to TNBC cells, we encapsulated miR-34a mimics in poly(lactic-co-glycolic acid) nanoparticles (NPs) that were functionalized with Notch1 antibodies to produce N1-34a-NPs. In addition to binding Notch1 receptors overexpressed on the surface of TNBC cells, the antibodies in this formulation enable suppression of Notch signaling through signal cascade interference. Herein, we present the results of in vitro experiments that demonstrate N1-34a-NPs can regulate Notch signaling and downstream miR-34a targets in TNBC cells to induce senescence and reduce cell proliferation and migration. These studies demonstrate that NP-mediated co-delivery of miR-34a and Notch1 antibodies is a promising alternative treatment strategy for TNBC, warranting further optimization and in vivo investigation in future studies.

11.
J Pain ; 20(1): 16.e1-16.e16, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30102991

RESUMO

Acupoint catgut embedding (ACE) is a widely used traditional Chinese medicine method to manage various diseases, including chronic inflammatory pain. We sought to assess the possible analgesic effects of ACE in comparison with electroacupuncture (EA) and to study the analgesic mechanisms of ACE in a rat model of inflammatory pain induced by injection of complete Freund's adjuvant (CFA) into the hind paw of rats. The von Frey, radiant heat, and gait analysis tests were performed to evaluate the analgesic effects of ACE and EA, and Western blot and immunohistochemistry assays were carried out to determine the molecular mechanisms of ACE. ACE treatments were administered every 4 days or every week with different acupoints (ipsilateral, contralateral, or bilateral ST36 and GB30 acupoints). The most effective ACE strategy for attenuating the nocifensive response induced by CFA injection was performing ACE once a week at ipsilateral ST36 in combination with GB30. EA treatment every other day at ipsilateral ST36 and GB30 showed comparable analgesic effects. ACE inhibited the increased activation of the GluN1 subunit of the N-methyl-d-aspartate receptor and the subsequent Ca2+-dependent signals (CaMKII, ERK, and CREB) that take place in response to CFA. The effects of ACE were similar to intrathecal injection of vilazodone (a serotonin 1A receptor [5-HT1AR] agonist) and were blocked by WAY-100635 (a 5-HT1AR antagonist). In summary, we show that ACE attenuates CFA-induced inflammatory pain in rats by activating spinal 5-HT1AR and by inhibiting the phosphorylation of GluN1, thus, inhibiting the activation of Ca2+-dependent signaling cascades. PERSPECTIVE: This article presents the novel evidence concerning the spinal 5-HT1AR activation-related molecular signaling of ACE analgesia in a rat model of CFA-induced inflammatory pain. This work may help clinicians to verify the effectiveness of ACE analgesia and to better understand the underlying mechanism.


Assuntos
Analgesia por Acupuntura , Pontos de Acupuntura , Categute , Eletroacupuntura , Inflamação/metabolismo , Manejo da Dor , Dor/metabolismo , Receptor 5-HT1A de Serotonina/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Agonistas do Receptor 5-HT1 de Serotonina/farmacologia , Analgesia por Acupuntura/métodos , Animais , Modelos Animais de Doenças , Eletroacupuntura/métodos , Adjuvante de Freund/farmacocinética , Inflamação/induzido quimicamente , Masculino , Dor/induzido quimicamente , Fosforilação , Ratos , Ratos Sprague-Dawley , Agonistas do Receptor 5-HT1 de Serotonina/administração & dosagem , Antagonistas do Receptor 5-HT1 de Serotonina/farmacologia , Medula Espinal/efeitos dos fármacos , Cloridrato de Vilazodona/farmacologia
12.
World J Clin Oncol ; 10(4): 166-182, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31114749

RESUMO

BACKGROUND: Aberrant activation of phosphorylated form of glycogen synthase kinase-3ß [pS9GSK-3ß (Serine 9 phosphorylation)] is known to trigger Wnt/ß-catenin signal cascade but its clinicohistopathological implications in bladder carcinogenesis remain unknown. AIM: To investigate the diagnostic and prognostic relevance of expressions of pS9GSK-3ß, ß-catenin and its target genes in the pathobiology of bladder cancer. METHODS: Bladder tumor tissues from ninety patients were analyzed for quantitative expression and cellular localization of pS9GSK-3ß by immunohistochemical (IHC) staining. Real time-quantitative polymerase chain reaction and IHC were done to check the expression of ß-catenin, Cyclin D1, Snail and Slug at transcriptome and protein level respectively. Clinicohistopathological variables were obtained from histology reports, follow up and OPD visits of patients. Expressions of the markers were statistically correlated with these variables to determine their significance in clinical setting. Results were analysed using SPSS 20.0 software. RESULTS: Aberrant (low or no membranous/high nuclear/high cytoplasmic) expression of pS9GSK-3ß was noted in 51% patients and found to be significantly associated with tumor stage and tumor grade (P = 0.01 and 0.04; Mann Whitney U test). Thirty one percent tumors exhibited aberrant co-expression of pS9GSK-3ß and ß-catenin proteins and showed strong statistical association with tumor stage, tumor type, smoking/tobacco chewing status (P = 0.01, 0.02 and 0.04, Mann-Whitney U test) and shorter overall survival probabilities of patients (P = 0.02; Kaplan Meier test). Nuclear immunostaining of Cyclin D1 in tumors with altered pS9GSK-3ß/ß-catenin showed relevance with tumor stage, grade and type. CONCLUSION: ß-catenin and pS9GSK-3ß proteins are identified as markers of diagnostic/prognostic significance in disease pathogenesis. Observed histopathological association of Cyclin D1 identifies it as marker of potential relevance in tumors with altered pS9GSK-3ß/ß-catenin.

13.
Adv Biol Regul ; 66: 72-84, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28552579

RESUMO

Cancer is a major problem in public health and is one of the leading causes of mortality worldwide. Many types of cancer cells exhibit aberrant cellular signal transduction in response to stress, which often leads to oncogenesis. Mitogen-activated protein kinase (MAPK) signal cascades are one of the important intracellular stress signaling pathways closely related to cancer. The key molecules in MAPK signal cascades that respond to various types of stressors are apoptosis signal-regulating kinase (ASK) family members; ASK1, ASK2 and ASK3. ASK family members are activated by a wide variety of stressors, and they regulate various cellular responses, such as cell proliferation, inflammation and apoptosis. In this review, we will discuss both the oncogenic and anti-oncogenic roles of the ASK family members in various contexts of cancer development with deeper insights into the involvement of ASK family members in cancer pathology.


Assuntos
MAP Quinase Quinase Quinase 5/metabolismo , Neoplasias/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Humanos , MAP Quinase Quinase Quinase 5/genética , Neoplasias/genética , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
14.
Exp Clin Cardiol ; 10(3): 170-2, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-19641683

RESUMO

After more than 15 years of intensive research in the field of functional autoantibodies (AAB) directed against G-protein-coupled receptors, there is growing evidence of a causal involvement of AAB in various cardiovascular diseases such as dilated cardiomyopathy, peripartum cardiomyopathy, malignant and essential hypertension, and preeclampsia. It has been indicated that AAB against beta-1 adrenergic receptor, alpha-1 adrenergic receptor, angiotensin-II receptor AT(1) and muscarinic M(2)-receptors undergo agonist-like actions on the corresponding receptor and induce a permanent stimulation of G-protein-coupled signal cascades, which may cause Ca(2+) overload and cardiomyocyte destruction.Furthermore, the present review describes how G-protein-coupled receptor AAB are able to activate transcription factor nuclear factor-kappa B, which may regulate the expression of genes involved in immune and inflammatory responses.

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