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1.
Nephrol Dial Transplant ; 39(2): 305-316, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-37451818

RESUMEN

BACKGROUND: In patients with chronic kidney disease (CKD), vascular calcification (VC) is common and is associated with a higher risk of all-cause mortality. Shh, one ligand for Hedgehog (Hh) signaling, participates in osteogenesis and several cardiovascular diseases. However, it remains unclear whether Shh is implicated in the development of VC. METHODS: Inorganic phosphorus 2.6 mM was used to induce vascular smooth muscle cells (VSMCs) calcification. Mice were fed with adenine diet supplement with 1.2% phosphorus to induce VC. RESULTS: Shh was decreased in VSMCs exposed to inorganic phosphorus, calcified arteries in mice fed with an adenine diet, as well as radial arteries from patients with CKD presenting VC. Overexpression of Shh inhibited VSMCs ostosteoblastic differentiation and calcification, whereas its silencing accelerated these processes. Likewise, mice treated with smoothened agonist (SAG; Hh signaling agonist) showed alleviated VC, and mice treated with cyclopamine (CPN; Hh signaling antagonist) exhibited severe VC. Additionally, overexpression of Gli2 significantly reversed the pro-calcification effect of Shh silencing on VSMCs, suggesting that Shh inhibited VC via Gli2. Mechanistically, Gli2 interacted with Runx2 and promoted its ubiquitin proteasomal degradation, therefore protecting against VC. Of interest, the pro-degradation effect of Gli2 on Runx2 was independent of Smurf1 and Cullin4B. CONCLUSIONS: Our study provided deeper insight to the pathogenesis of VC, and Shh might be a novel potential target for VC treatment.


Asunto(s)
Insuficiencia Renal Crónica , Calcificación Vascular , Humanos , Ratones , Animales , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/farmacología , Calcificación Vascular/etiología , Calcificación Vascular/prevención & control , Calcificación Vascular/metabolismo , Insuficiencia Renal Crónica/patología , Fósforo/metabolismo , Adenina , Miocitos del Músculo Liso/metabolismo , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo
2.
Infection ; 52(2): 301-311, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37926767

RESUMEN

PURPOSE: The prevalence of odontogenic infections remains one of the highest in the world. If untreated, odontogenic infections can break through the limitation, disseminate to other organs or spaces, and cause high mortality rates. However, it is still difficult to rapidly target limited or disseminated infections in clinical practice. The type of disseminated odontogenic infections and the responsible bacteria have not been described in detail. METHODS: Search databases (e.g., PubMed, MEDLINE, Web of Science, Embase) for reports published from 2018.1 to 2022.9. Use search strategies: ("odontogenic infections" OR "pulpitis" OR "periapical lesions" OR "periodontal diseases") AND ("disseminated infections" OR "complication"). RESULTS: Fourteen different types of disseminated odontogenic infections, most of which are polymicrobial infections, can spread through the body either direct or through hematogenous diffusion. Multiple microbial infections can be more invasive in the transmission of infection. Secondary infections are commonly associated with bacteria like Fusobacterium spp., Streptococcus spp., Peptostreptococcus spp., Prevotella spp., and Staphylococcus spp. Antibiotics with broad-spectrum activity are fundamental as first-line antimicrobial agents based on the microorganisms isolated from disseminated infections. CONCLUSION: This review elaborates on the epidemiology, microorganisms, risk factors, and dissemination routes, and provides evidence-based opinions on the diagnosis, multidisciplinary management, and prevention of odontogenic infections for dentists and clinicians.


Asunto(s)
Antibacterianos , Bacterias , Humanos , Antibacterianos/uso terapéutico , Streptococcus
3.
Int J Med Microbiol ; 313(1): 151573, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36634604

RESUMEN

Uropathogenic Escherichia coli (UPEC) are causative agent that causes urinary tract infections (UTIs) and the recent emergence of multidrug resistance (MDR) of UPEC increases the burden on the community. Recent studies of bacterial outer membrane vesicles (OMV) identified various factors including proteins, nucleic acids, and small molecules which provided inter-cellular communication within the bacterial population. However, the components of UPEC-specific OMVs and their functional role remain unclear. Here, we systematically determined the proteomes of UPEC-OMVs and identified the specific components that provide functions to the recipient bacteria. Based on the functional network of OMVs' proteomes, a group of signaling peptides was found in all OMVs which provide communication among bacteria. Moreover, we demonstrated that treatment with UPEC-OMVs affected the motility and biofilm formation of the recipient bacteria, and further identified aromatic amino acid (AAA) biosynthesis proteins as the key factors to provide their movement.


Asunto(s)
Infecciones por Escherichia coli , Proteínas de Escherichia coli , Infecciones Urinarias , Escherichia coli Uropatógena , Humanos , Proteínas de Escherichia coli/metabolismo , Proteoma/metabolismo , Infecciones Urinarias/microbiología , Infecciones por Escherichia coli/microbiología
4.
Int J Mol Sci ; 24(5)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36902234

RESUMEN

BG45 is a class Ⅰ histone deacetylase inhibitor (HDACI) with selectivity for HDAC3. Our previous study demonstrated that BG45 can upregulate the expression of synaptic proteins and reduce the loss of neurons in the hippocampus of APPswe/PS1dE9 (APP/PS1) transgenic mice (Tg). The entorhinal cortex is a pivotal region that, along with the hippocampus, plays a critical role in memory in the Alzheimer's disease (AD) pathology process. In this study, we focused on the inflammatory changes in the entorhinal cortex of APP/PS1 mice and further explored the therapeutic effects of BG45 on the pathologies. The APP/PS1 mice were randomly divided into the transgenic group without BG45 (Tg group) and the BG45-treated groups. The BG45-treated groups were treated with BG45 at 2 months (2 m group), at 6 months (6 m group), or twice at 2 and 6 months (2 and 6 m group). The wild-type mice group (Wt group) served as the control. All mice were killed within 24 h after the last injection at 6 months. The results showed that amyloid-ß (Aß) deposition and IBA1-positive microglia and GFAP-positive astrocytes in the entorhinal cortex of the APP/PS1 mice progressively increased over time from 3 to 8 months of age. When the APP/PS1 mice were treated with BG45, the level of H3K9K14/H3 acetylation was improved and the expression of histonedeacetylase1, histonedeacetylase2, and histonedeacetylase3 was inhibited, especially in the 2 and 6 m group. BG45 alleviated Aß deposition and reduced the phosphorylation level of tau protein. The number of IBA1-positive microglia and GFAP-positive astrocytes decreased with BG45 treatment, and the effect was more significant in the 2 and 6 m group. Meanwhile, the expression of synaptic proteins synaptophysin, postsynaptic density protein 95, and spinophilin was upregulated and the degeneration of neurons was alleviated. Moreover, BG45 reduced the gene expression of inflammatory cytokines interleukin-1ß and tumor necrosis factor-α. Closely related to the CREB/BDNF/NF-kB pathway, the expression of p-CREB/CREB, BDNF, and TrkB was increased in all BG45 administered groups compared with the Tg group. However, the levels of p-NF-kB/NF-kB in the BG45 treatment groups were reduced. Therefore, we deduced that BG45 is a potential drug for AD by alleviating inflammation and regulating the CREB/BDNF/NF-kB pathway, and the early, repeated administration of BG45 can play a more effective role.


Asunto(s)
Enfermedad de Alzheimer , Precursor de Proteína beta-Amiloide , Corteza Entorrinal , Inhibidores de Histona Desacetilasas , Inflamación , Microglía , Animales , Ratones , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Modelos Animales de Enfermedad , Corteza Entorrinal/metabolismo , Hipocampo/metabolismo , Inflamación/metabolismo , Ratones Transgénicos , Microglía/metabolismo , FN-kappa B/metabolismo , Presenilina-1/genética , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Histona Desacetilasas/uso terapéutico
5.
Anal Chem ; 94(3): 1901-1909, 2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35019258

RESUMEN

Surface biotinylation has been widely adapted in profiling the cellular proteome associated with the plasma membrane. However, the workflow is subject to interference from the cytoplasmic biotin-associated proteins that compete for streptavidin-binding during purification. Here we established a bioorthogonal conjugation-assisted purification (BCAP) workflow that utilizes the Staudinger chemoselective ligation to label and isolate surface-associated proteins while minimizing the binding of endogenous biotin-associated proteins. Label-free quantitative proteomics demonstrated that BCAP is efficient in isolating cell surface proteins with excellent reproducibility. Subsequently, we applied BCAP to compare the surface proteome of proliferating and senescent mouse embryonic fibroblasts (MEFs). Among the results, EHD2 was identified and validated as a novel protein that is enhanced at the cell surface of senescent MEFs. We expect that BCAP will have broad applications in profiling cell surface proteomes in the future.


Asunto(s)
Proteoma , Proteómica , Animales , Biotinilación , Proteínas Portadoras/metabolismo , Membrana Celular/metabolismo , Fibroblastos/metabolismo , Espectrometría de Masas , Ratones , Proteoma/metabolismo , Proteómica/métodos , Reproducibilidad de los Resultados
6.
BMC Med Educ ; 22(1): 817, 2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36447283

RESUMEN

BACKGROUND: Students' engagement with learning materials and discussions with teachers and peers before and after lectures are among the keys to the successful implementation of blended programs. Mixed results have been reported by previous studies on blended learning. This study evaluated the effectiveness of embedding a teacher-supervised online discussion platform in a blended embryology course in terms of its impact on students' capabilities to handle difficult and cognitively challenging tasks. METHODS: Two forms of blended learning were investigated and compared in this study. Students in the control group (n = 85) learned online materials before each class, followed by classroom instruction and activities in which face-to-face discussion and communication between students were encouraged. Students in the experimental group (n = 83) followed a similar procedure with an additional teacher-supervised online discussion platform to guide, supervise and evaluate their learning progress. All participants were first-year medical students in clinical medicine at Dalian Medical University who had enrolled in 2017. All participants took the final exam to test their learning outcomes. RESULTS: The embryology grades of students in the experimental group were significantly higher than those of students in the control group (p = 0.001). Additionally, the scores of students in the experimental group on questions with a high difficulty level (p = 0.003) and questions assessing high-order cognitive skills (p = 0.003) were higher than those of students in the control group; the effect size was moderate (η2 > 0.05). CONCLUSIONS: In blended embryology courses, compared with learner-led and face-to-face discussion, the teacher-supervised online discussion platform has great potential to enable students to achieve higher grades and solve difficult and cognitively challenging tasks.


Asunto(s)
Personal Docente , Estudiantes de Medicina , Humanos , Tecnología , Aprendizaje , Universidades
7.
Molecules ; 27(13)2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35807406

RESUMEN

As a neurodegenerative disease, Alzheimer's disease (AD) seriously affects the health of older people. Changes in synapses occur first over the course of the disease, perhaps even before the formation of Aß plaques. Histone deacetylase (HDAC) mediates the damage of Aß oligomers to dendritic spines. Therefore, we examined the relationship between HDAC activity and synaptic defects using an HDAC inhibitor (HDACI), BG45, in the human neuroblastoma SH-SY5Y cell line with stable overexpression of Swedish mutant APP (APPsw) and in APP/PS1 transgenic mice during this study. The cells were treated with 15 µM BG45 and the APP/PS1 mice were treated with 30 mg/kg BG45. We detected the levels of synapse-related proteins, HDACs, tau phosphorylation, and amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors using Western blotting and immunohistochemistry. We also measured the expression of cytoskeletal proteins in the cell model. The mRNA levels of the glutamate ion receptor alginate subunit 2 (GRIK2), sodium voltage-gated channel beta subunit (SCN3B), synaptophysin (SYP), Grm2 (the gene encoding glutamate receptor subunit 2 (GluR2)), Grid2IP, glutamate receptor interacting protein 1 (GRIP1), and GRIP2 were detected to explore the effects of the HDACI on regulating the expression of synaptic proteins and AMPA receptors. According to our studies, the expressions of HDAC1, HDAC2, and HDAC3 were increased, which were accompanied by the downregulation of the synapse-related proteins SYP, postsynaptic dendritic protein (PSD-95), and spinophilin as early as 24 h after transfection with the APPsw gene. BG45 upregulated the expression of synapse-related proteins and repaired cytoskeletal damage. In vivo, BG45 alleviated the apoptosis-mediated loss of hippocampal neurons, upregulated synapse-related proteins, reduced Aß deposition and phosphorylation of tau, and increased the levels of the synapse-related genes GRIK2, SCN3B, SYP, Grm2, and Grid2IP. BG45 increased the expression of the AMPA receptor subunits GluA1, GluA2, and GluA3 on APPsw-transfected cells and increased GRIP1 and GRIP2 expression and AMPA receptor phosphorylation in vivo. Based on these results, HDACs are involved in the early process of synaptic defects in AD models, and BG45 may rescue synaptic damage and the loss of hippocampal neurons by specifically inhibiting HDAC1, HDAC2, and HDAC3, thereby modulating AMPA receptor transduction, increasing synapse-related gene expression, and finally enhancing the function of excitatory synapses. BG45 may be considered a potential drug for the treatment of early AD in further studies.


Asunto(s)
Enfermedad de Alzheimer , Neuroblastoma , Enfermedades Neurodegenerativas , Proteínas Adaptadoras Transductoras de Señales , Anciano , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Proteínas Portadoras , Modelos Animales de Enfermedad , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Histona Desacetilasas/uso terapéutico , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ratones , Ratones Transgénicos , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Receptores AMPA/genética , Receptores AMPA/metabolismo , Receptores AMPA/uso terapéutico , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/uso terapéutico
8.
J Proteome Res ; 20(3): 1783-1791, 2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33630606

RESUMEN

Stony corals form the foundation of coral reefs, which are of prominent ecological and economic significance. A robust workflow for investigating the coral proteome is essential in understanding coral biology. Here we investigated different preparative workflows and characterized the proteome of Platygyra carnosa, a common stony coral of the South China Sea. We found that a combination of bead homogenization with suspension trapping (S-Trap) preparation could yield more than 2700 proteins from coral samples. Annotation using a P. carnosa transcriptome database revealed that the majority of proteins were from the coral host cells (2140, 212, and 427 proteins from host coral, dinoflagellate, and other compartments, respectively). Label-free quantification and functional annotations indicated that a high proportion were involved in protein and redox homeostasis. Furthermore, the S-Trap method achieved good reproducibility in quantitative analysis. Although yielding a low symbiont:host ratio, the method is efficient in characterizing the coral host proteomic landscape, which provides a foundation to explore the molecular basis of the responses of coral host tissues to environmental stressors.


Asunto(s)
Antozoos , Animales , Antozoos/genética , China , Proteoma/genética , Proteómica , Reproducibilidad de los Resultados , Simbiosis
9.
Sensors (Basel) ; 21(18)2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34577404

RESUMEN

Nowadays, engineers are widely using accelerometers to record the vibration of structures for structural verification purposes. The main obstacle for using these data acquisition systems is their high cost, which limits its use to unique structures with a relatively high structural health monitoring budget. In this paper, a Cost Hyper-Efficient Arduino Product (CHEAP) has been developed to accurately measure structural accelerations. CHEAP is a system that is composed of five low-cost accelerometers that are connected to an Arduino microcontroller as their data acquisition system. Test results show that CHEAP not only has a significantly lower price (14 times cheaper in the worst-case scenario) compared with other systems used for comparison but also shows better accuracy on low frequencies for low acceleration amplitudes. Moreover, the final output results of Fast Fourier Transformation (FFT) assessments showed a better observable resolution for CHEAP than the studied control systems.


Asunto(s)
Aceleración , Vibración
10.
J Sep Sci ; 42(9): 1725-1732, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30839168

RESUMEN

Leonurus japonicus houtt, a well-known herb of traditional Chinese medicine, is widely used to treat gynaecological diseases. In this study, a rapid and sensitive liquid chromatography with tandem mass spectrometry method for simultaneously quantifying leonurine and stachydrine, the two main bioactive components in Leonurus japonicus houtt, was developed and validated. Plasma samples were prepared by protein precipitation with acetonitrile and separation by a Hewlett Packard XDB-C8 column (150 × 4.6 mm, id, 5 µm) equipped with a gradient elution system containing methanol-water and 0.1% formic acid at a flow-rate of 0.4 mL/min. Components were then detected by a mass spectrometer in positive electrospray ionization mode. This method showed good linearity, precision, accuracy, recovery, stability, and negligible matrix effects, which were within acceptable ranges. The method was successfully applied to compare the pharmacokinetics in normal rats and rats with cold-stagnation and blood-stasis primary dysmenorrhoea treated with Leonurus japonicus houtt electuary. The result showed significant differences (p < 0.05) in the pharmacokinetic parameters between the primary dysmenorrhoea and normal groups. This result implied that Leonurus japonicus houtt electuary remained longer and was absorbed slower in rats with primary dysmenorrhoea and exhibited higher bioavailability and peak concentration.


Asunto(s)
Medicamentos Herbarios Chinos/farmacocinética , Dismenorrea/tratamiento farmacológico , Ácido Gálico/análogos & derivados , Leonurus/química , Prolina/análogos & derivados , Animales , Medicamentos Herbarios Chinos/administración & dosificación , Dismenorrea/sangre , Femenino , Ácido Gálico/administración & dosificación , Ácido Gálico/farmacocinética , Humanos , Prolina/administración & dosificación , Prolina/farmacocinética , Ratas , Ratas Sprague-Dawley
11.
Neurochem Res ; 42(11): 3073-3083, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28780733

RESUMEN

Brain-derived neurotrophic factor (BDNF) plays an important role in promoting the growth, differentiation, survival and synaptic stability of neurons. Presently, the transplantation of neural stem cells (NSCs) is known to induce neural repair to some extent after injury or disease. In this study, to investigate whether NSCs genetically modified to encode the BDNF gene (BDNF/NSCs) would further enhance synaptogenesis, BDNF/NSCs or naive NSCs were directly engrafted into lesions in a rat model of traumatic brain injury (TBI). Immunohistochemistry, western blotting and RT-PCR were performed to detect synaptic proteins, BDNF-TrkB and its downstream signaling pathways, at 1, 2, 3 or 4 weeks after transplantation. Our results showed that BDNF significantly increased the expression levels of the TrkB receptor gene and the phosphorylation of the TrkB protein in the lesions. The expression levels of Ras, phosphorylated Erk1/2 and postsynaptic density protein-95 were elevated in the BDNF/NSCs-transplanted groups compared with those in the NSCs-transplanted groups throughout the experimental period. Moreover, the nuclear factor (erythroid-derived 2)-like 2/Thioredoxin (Nrf2/Trx) axis, which is a specific therapeutic target for the treatment of injury or cell death, was upregulated by BDNF overexpression. Therefore, we determined that the increased synaptic proteins level implicated in synaptogenesis might be associated with the activation of the MAPK/Erk1/2 signaling pathway and the upregulation of the antioxidant agent Trx modified by BDNF-TrkB following the BDNF/NSCs transplantation after TBI.


Asunto(s)
Lesiones Traumáticas del Encéfalo/metabolismo , Factor Neurotrófico Derivado del Encéfalo/biosíntesis , Sistema de Señalización de MAP Quinasas/fisiología , Quinasas de Proteína Quinasa Activadas por Mitógenos/biosíntesis , Factor 2 Relacionado con NF-E2/biosíntesis , Células-Madre Neurales/trasplante , Tiorredoxinas/biosíntesis , Animales , Lesiones Traumáticas del Encéfalo/terapia , Factor Neurotrófico Derivado del Encéfalo/administración & dosificación , Modelos Animales de Enfermedad , Células Madre Embrionarias/trasplante , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Ratas , Ratas Wistar , Trasplante de Células Madre/métodos , Sinapsis/efectos de los fármacos , Sinapsis/metabolismo , Tiorredoxinas/metabolismo
12.
Cell Physiol Biochem ; 40(6): 1401-1409, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27997887

RESUMEN

BACKGROUND/AIMS: Extensive studies have demonstrated that Bleomycin (BLM) is a glycopeptide antibiotic that has been used as an anticancer chemotherapeutic reagent. It can induce both single- and double-strand DNA damage, inhibit synthesis of DNA, suppress proliferation, and induce apoptosis in cancer cells. Smad signaling transducers are considered as important molecules in tumor development and progression, and may closely be related to the biological behaviors of some malignant carcinomas, including gastric cancer. METHODS: The effects of different concentrations of BLM on the proliferation, cell cycle, apoptosis, migration, and invasion on gastric cancer cell lines MKN45 and AGS were assayed by using CCK-8 assay, Annexin V/PI double staining, PI staining, and transwell assay. Western blot and Immunohistochemistry were applied to analyze the potential mechanism(s). RESULTS: BLM treatment resulted in a low proliferation, high apoptosis, low migration and invasion in MKN45 and AGS cells. Furthermore, the possible mechanisms underlying that Smad3 activity could be changed after binding with BLM, and subsequently the Smad signaling pathway had a cascade response. CONCLUSION: These results highlight BLM as an exciting theme for gastric cancer treatment, which may represent an effective clinical therapeutic reagent for gastric cancer patients.


Asunto(s)
Bleomicina/farmacología , Movimiento Celular/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Proteínas Smad/metabolismo , Neoplasias Gástricas/patología , Western Blotting , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Modelos Moleculares , Fenotipo , Fosforilación/efectos de los fármacos
13.
Exp Eye Res ; 132: 136-50, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25643624

RESUMEN

The ionotropic glutamate receptors (iGLuR) have been hypothesized to play a role in neuronal pathogenesis by mediating excitotoxic death. Previous studies on iGluR in the retina have focused on two broad classes of receptors: NMDA and non-NMDA receptors including the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic receptor (AMPAR) and kainate receptor. In this study, we examined the role of receptor desensitization on the specific excitotoxic effects of AMPAR activation on primary retinal ganglion cells (RGCs). Purified rat RGCs were isolated from postnatal day 4-7 Sprague-Dawley rats. Calcium imaging was used to identify the functionality of the AMPARs and selectivity of the s-AMPA agonist. Phosphorylated CREB and ERK1/2 expression were performed following s-AMPA treatment. s-AMPA excitotoxicity was determined by JC-1 mitochondrial membrane depolarization assay, caspase 3/7 luciferase activity assay, immunoblot analysis for α-fodrin, and Live (calcein AM)/Dead (ethidium homodimer-1) assay. RGC cultures of 98% purity, lacking Iba1 and GFAP expression were used for the present studies. Isolated prenatal RGCs expressed calcium permeable AMPAR and s-AMPA (100 µM) treatment of cultured RGCs significantly increased phosphorylation of CREB but not that of ERK1/2. A prolonged (6 h) AMPAR activation in purified RGCs using s-AMPA (100 µM) did not depolarize the RGC mitochondrial membrane potential. In addition, treatment of cultured RGCs with s-AMPA, both in the presence and absence of trophic factors (BDNF and CNTF), did not increase caspase 3/7 activities or the cleavage of α-fodrin (neuronal apoptosis marker), as compared to untreated controls. Lastly, a significant increase in cell survival of RGCs was observed after s-AMPA treatment as compared to control untreated RGCs. However, preventing the desensitization of AMPAR with the treatment with either kainic acid (100 µM) or the combination of s-AMPA and cyclothiazide (50 µM) significantly reduced cell survivability. Activation of the AMPAR in RGCs does not appear to activate a signaling cascade to apoptosis, suggesting that RGCs in vitro are not susceptible to AMPA excitotoxicity as previously hypothesized. Conversely, preventing AMPAR desensitization through differential agonist activation caused AMPAR mediated excitotoxicity. Activation of the AMPAR in increasing CREB phosphorylation was dependent on the presence of calcium, which may help explain this action in increasing RGC survival.


Asunto(s)
Receptores AMPA/fisiología , Células Ganglionares de la Retina/metabolismo , Animales , Proteína de Unión a CREB/metabolismo , Caspasas/metabolismo , Células Cultivadas , Agonistas de Aminoácidos Excitadores/farmacología , Sistema de Señalización de MAP Quinasas/fisiología , Masculino , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Modelos Animales , Ratas , Ratas Sprague-Dawley , Receptores AMPA/agonistas , Receptores AMPA/metabolismo , Células Ganglionares de la Retina/efectos de los fármacos , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico/farmacología
14.
Toxicol Appl Pharmacol ; 277(1): 86-94, 2014 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-24631340

RESUMEN

Herb-drug interaction strongly limits the clinical application of herbs and drugs, and the inhibition of herbal components towards important drug-metabolizing enzymes (DMEs) has been regarded as one of the most important reasons. The present study aims to investigate the inhibition potential of andrographolide derivatives towards one of the most important phase II DMEs UDP-glucuronosyltransferases (UGTs). Recombinant UGT isoforms (except UGT1A4)-catalyzed 4-methylumbelliferone (4-MU) glucuronidation reaction and UGT1A4-catalyzed trifluoperazine (TFP) glucuronidation were employed to firstly screen the andrographolide derivatives' inhibition potential. High specific inhibition of andrographolide derivatives towards UGT2B7 was observed. The inhibition type and parameters (Ki) were determined for the compounds exhibiting strong inhibition capability towards UGT2B7, and human liver microsome (HLMs)-catalyzed zidovudine (AZT) glucuronidation probe reaction was used to furtherly confirm the inhibition behavior. In combination of inhibition parameters (Ki) and in vivo concentration of andrographolide and dehydroandrographolide, the potential in vivo inhibition magnitude was predicted. Additionally, both the in vitro inhibition data and computational modeling results provide important information for the modification of andrographolide derivatives as selective inhibitors of UGT2B7. Taken together, data obtained from the present study indicated the potential herb-drug interaction between Andrographis paniculata and the drugs mainly undergoing UGT2B7-catalyzed metabolic elimination, and the andrographolide derivatives as potential candidates for the selective inhibitors of UGT2B7.


Asunto(s)
Andrographis , Diterpenos/metabolismo , Glucuronosiltransferasa/metabolismo , Interacciones de Hierba-Droga , Diterpenos/química , Represión Enzimática/efectos de los fármacos , Glucuronosiltransferasa/efectos de los fármacos , Humanos , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/enzimología
15.
Exp Eye Res ; 128: 156-69, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25305575

RESUMEN

Sigma-1 receptor (σ-1) activation and mitogen-activated protein kinases (MAPKs) have been shown to protect retinal ganglion cells (RGCs) from cell death. The purpose of this study was to determine if σ-1 receptor stimulation with pentazocine could promote neuroprotection under conditions of an ischemia-like insult (oxygen glucose deprivation (OGD)) through the phosphorylation of extracellular signal regulated kinase (pERK)1/2. Primary RGCs were isolated from P3-P7 Sprague-Dawley rats and purified by sequential immunopanning using Thy1.1 antibodies. RGCs were cultured for 7 days before subjecting the cells to an OGD insult (0.5% oxygen in glucose-free medium) for 6 h. During the OGD, RGCs were treated with pentazocine (σ-1 receptor agonist) with or without BD 1047 (σ-1 receptor antagonist). In other experiments, primary RGCs were treated with pentazocine in the presence or absence of an MEK1/2 inhibitor, PD098059. Cell survival/death was assessed by staining with the calcein-AM/ethidium homodimer reagent. Levels of pERK1/2, total ERK1/2, and beta tubulin expression were determined by immunoblotting and immunofluorescence staining. RGCs subjected to OGD for 6 h induced 50% cell death in primary RGCs (p < 0.001) and inhibited pERK1/2 expression by 65% (p < 0.001). Cell death was attenuated when RGCs were treated with pentazocine under OGD (p < 0.001) and pERK1/2 expression was increased by 1.6 fold (p < 0.05) compared to OGD treated RGCs without pentazocine treatment. The co-treatment of PD098059 (MEK1/2 inhibitor) with pentazocine significantly abolished the protective effects of pentazocine on the RGCs during this OGD insult. Activation of the σ-1 receptor is a neuroprotective target that can protect RGCs from an ischemia-like insult. These results also established a direct relationship between σ-1 receptor stimulation and the neuroprotective effects of the ERK1/2 pathway in purified RGCs subjected to OGD. These findings suggest that activation of the σ-1 receptor may be a therapeutic target for neuroprotection particularly relevant to ocular neurodegenerative diseases that effect RGCs.


Asunto(s)
Analgésicos Opioides/farmacología , Isquemia/prevención & control , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Pentazocina/farmacología , Receptores sigma/metabolismo , Células Ganglionares de la Retina/efectos de los fármacos , Animales , Western Blotting , Supervivencia Celular , Células Cultivadas , Inhibidores Enzimáticos/farmacología , Técnica del Anticuerpo Fluorescente Indirecta , Glucosa/metabolismo , Isquemia/enzimología , Proteína Quinasa 1 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 3 Activada por Mitógenos/antagonistas & inhibidores , Oxígeno/metabolismo , Fosforilación , Ratas , Ratas Sprague-Dawley , Células Ganglionares de la Retina/enzimología , Receptor Sigma-1
16.
Int J Mol Sci ; 15(2): 1983-2002, 2014 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-24473145

RESUMEN

Apoptosis and necrosis of intestinal epithelial cells (IECs), induced by ischemia-reperfusion (I/R) injury, can lead to dysfunction of the intestinal barrier, which could cause multiple organ dysfunction syndromes. Mesenchymal stem cells (MSCs) have the potential of providing protective effects on damaged IECs via paracrine action. This study investigated whether hypoxia can enhance the protective effect of placental-derived MSCs (pMSCs) on H2O2-treated-caco2 cells, and explored the possible mechanism. The pMSCs isolated by tissue culture were fibroblast-like, positive for CD73, CD90 and CD105 and can differentiate into chondrocytes and endothelial cells. Five days after treatment with H2O2, the numbers of living caco2 cells significantly decreased. More live H2O2-treated-caco2 cells were observed in pMSCs hypoxia culture medium (pMSCs-HCM) than pMSCs normoxia culture medium (pMSCs-NCM), and the application of a specific antibody that blocked insulin-like growth factor-1 (IGF-1) leads to a significant decrease of the protective effect of pMSCs-HCM. Hypoxia can promote IGF-1 expression of pMSCs at mRNA and protein levels, and caco2 stably expressed IGF-1 receptor. Knocking down IGF-1 expression in pMSCs by siRNA resulted in a significant attenuation of the increase in apoptosis of H2O2-treated-caco2 cultured in pMSCs-HCM. In conclusion, hypoxia can increase the protective effect of pMSCs on H2O2-treated-caco2 cells via a promotion of their paracrine actions, and the key cytokine involved is IGF-1.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina/biosíntesis , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Células Madre Mesenquimatosas/metabolismo , Placenta/citología , Apoptosis/efectos de los fármacos , Células CACO-2/efectos de los fármacos , Técnicas de Cultivo de Célula , Diferenciación Celular , Hipoxia de la Célula , Proliferación Celular/efectos de los fármacos , Medios de Cultivo Condicionados/farmacología , Células Endoteliales/citología , Células Endoteliales/metabolismo , Células Epiteliales/metabolismo , Femenino , Humanos , Peróxido de Hidrógeno/farmacología , Hipoxia , Inmunofenotipificación , Células Madre Mesenquimatosas/citología , Fenotipo , Embarazo , Daño por Reperfusión/metabolismo
17.
ISA Trans ; 145: 355-361, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38172035

RESUMEN

Current prescribed performance control (PPC) focuses on continuous-time systems, while this article proposes a novel discrete-time version of PPC for finite-time tracking of seeker stabilized platform in the discrete-time domain. Firstly, the newly developed performance functions are employed to impose finite-time prescribed performance on tracking errors. After that, a type of stabilization functions with respect to transformed errors are constructed for back-stepping controllers designing. On this basis, transformed errors are indirectly stabilized, and thus the pursued prescribed transient and steady-state behaviors are ensured for tracking errors via Lyapunov synthesis. Different from existing sliding-mode-control based discrete-time PPC, the addressed approach eliminates the sliding-mode structure and hence avoids high frequency chattering caused by such framework. Finally, compared simulations validate the superiority over existing methods.

18.
Proteomics Clin Appl ; 18(2): e2300004, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37574260

RESUMEN

PURPOSE: Urine proteome is a valuable reservoir of biomarkers for disease diagnosis and monitoring. Following formation as the plasma filtrate in the kidney, urine is progressively modified by the active reabsorption and secretion of the urinary tract. However, little is known about how the urine proteome changes as it passes along the urinary tract. EXPERIMENTAL DESIGN: To investigate this, we compared the proteome composition of the renal pelvis urine (RPU) and individually self-voided bladder urine (BU) collected from seven unilateral urinary tract obstruction male patients by LC-MS/MS screening. To our knowledge, this is the first proteomic comparison of RPU and BU samples from the same individual. RESULTS: Overall, RPU and BU proteomes did not exhibit proteins that were exclusively present in all samples of one urine type while in none of the other type. Nonetheless, BU had more overrepresented proteins that were observed at a higher frequency than RPU. Label-free quantitative analyses revealed BU-RPU differential proteins that are enriched in exosomes and extracellular proteins. However, the differences were not significant after corrections for multiple testing. Interestingly, we observed a significant increase of collagen peptides with hydroxyproline modifications in the BU samples, suggesting differences in protein modifications. CONCLUSIONS AND CLINICAL RELEVANCE: Our study revealed no substantial differences at the protein level between the BU and RPU samples. Future investigations with expanded cohorts would provide more insights about the urothelial-urinary interactions.


Asunto(s)
Proteoma , Vejiga Urinaria , Humanos , Masculino , Proteoma/análisis , Vejiga Urinaria/química , Vejiga Urinaria/metabolismo , Cromatografía Liquida , Proteómica , Espectrometría de Masas en Tándem , Pelvis Renal/química , Pelvis Renal/metabolismo
19.
Nanoscale ; 16(25): 12095-12106, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38819371

RESUMEN

Triple-negative breast cancer (TNBC) is known for its strong invasiveness, high recurrence rates, and poor prognosis. Heme oxygenase-1 (HO-1) is closely related to tumor invasion, metastasis, recurrence and formation of tumor immunosuppression. The expression of HO-1 is high in TNBC and low in normal tissues. In this study, AgPPIX was synthesized as a heme oxygenase-1 (HO-1) inhibitor and a photosensitizer for TNBC therapy. PDA nanoparticles were synthesized and modified with anti-CD24 and p-toluenesulfonamide (PTSC) on their both sides to obtain PTSC@AgPPIX/PDA@anti-CD24 Janus nanoparticles (PAPC) for AgPPIX-targeted delivery. Anti-CD24 is targeted to CD24 on tumor cells and the PTSC moiety is targeted to endoplasmic reticulum (ER), where HO-1 is located. The results indicated that PAPC Janus nanoparticles exhibited higher cytotoxicity in 4T1 cells than that of the mono-modified nanoparticles. PAPC not only inhibited the expression of HO-1 and VEGF but also reduced TrxR activity significantly. Furthermore, PAPC not only promoted intracellular ROS production under laser irradiation for tumor photodynamic therapy (PDT) but also polarized TAMs from M2-type to M1 for tumor immunotherapy. In vivo experiments confirmed that PAPC could remodel the tumor immune microenvironment and almost completely inhibit the tumor growth in mouse models. Therefore, PAPC Janus nanoparticles are a promising nanoplatform with a dual-targeting capacity for TNBC immune/PDT synergistic therapy.


Asunto(s)
Retículo Endoplásmico , Inmunoterapia , Nanopartículas , Fotoquimioterapia , Fármacos Fotosensibilizantes , Neoplasias de la Mama Triple Negativas , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/metabolismo , Animales , Ratones , Femenino , Línea Celular Tumoral , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Nanopartículas/química , Retículo Endoplásmico/metabolismo , Humanos , Hemo-Oxigenasa 1/metabolismo , Ratones Endogámicos BALB C , Especies Reactivas de Oxígeno/metabolismo , Plata/química , Plata/farmacología , Porfirinas/química , Porfirinas/farmacología
20.
Carcinogenesis ; 34(1): 146-52, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23054609

RESUMEN

Secreted frizzled-related protein 5 (SFRP5) is frequently found downregulated in gastric cancer due to SFRP5 gene hypermethylation, and there is a great necessity to elucidate the role of its downregulation in gastric cancer. By binding Wnt molecules, SFRP5 is generally supposed to exert negative effects on Wnt signal pathways widely linked to human cancers. This study found that macrophages over-produced Wnt5a under the stimulation of Lipopolysaccharide (LPS) or Helicobacter pylori, the most common infectious agent in human stomach. Wnt5a-conditioned medium from macrophages enhanced cell migration and CXCR4 expression in either SFRP5-negative gastric epithelial cells (GEC) harboring SFRP5 methylation or SFRP5-positive cells treated with SFRP5 small interfering RNA (siRNA). However, such induced effect was remarkably eliminated by either Wnt5a siRNA in macrophages or treatment with recombinant SFRP5. We also found that Wnt5a-conditioned medium stimulated phosphorylation of c-jun N-terminal kinase (JNK) and c-Jun, and JNK inhibitor SP600125 blocked Wnt5a-induced CXCR4 expression and cell migration in SFRP5-negative cells. Taken together, these findings suggest that epithelium-derived SFRP5 may play a probable defensive role in impeding gastric cancer progression, characteristically by inhibiting GEC migration induced by macrophage-derived Wnt5a via JNK signaling activation.


Asunto(s)
Proteínas del Ojo/fisiología , Macrófagos/fisiología , Proteínas de la Membrana/fisiología , Proteínas Proto-Oncogénicas/fisiología , Neoplasias Gástricas/patología , Proteínas Wnt/fisiología , Proteínas Adaptadoras Transductoras de Señales , Línea Celular Tumoral , Metilación de ADN , Células Epiteliales/citología , Proteínas del Ojo/genética , Humanos , Proteínas de la Membrana/genética , ARN Interferente Pequeño , Proteína Wnt-5a
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