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1.
bioRxiv ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38586011

RESUMO

Microglia-driven neuroinflammation plays an important role in the development of Alzheimer's disease (AD). Microglia activation is accompanied by the formation and chronic maintenance of TLR4 inflammarafts, defined as enlarged and cholesterol-rich lipid rafts serving as an assembly platform for TLR4 dimers and complexes of other inflammatory receptors. The secreted apoA-I binding protein (APOA1BP or AIBP) binds TLR4 and selectively targets cholesterol depletion machinery to TLR4 inflammaraft expressing inflammatory, but not homeostatic microglia. Here we demonstrated that amyloid-beta (Aß) induced formation of TLR4 inflammarafts in microglia in vitro and in the brain of APP/PS1 mice. Mitochondria in Apoa1bp-/- APP/PS1 microglia were hyperbranched and cupped, which was accompanied by increased ROS and the dilated ER. The size and number of Aß plaques and neuronal cell death were significantly increased, and the animal survival was decreased in Apoa1bp-/- APP/PS1 compared to APP/PS1 female mice. These results suggest that AIBP exerts control of TLR4 inflammarafts and mitochondrial dynamics in microglia and plays a protective role in AD associated oxidative stress and neurodegeneration.

2.
Cells ; 13(2)2024 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-38275823

RESUMO

Glaucoma is a group of ocular diseases that cause irreversible blindness. It is characterized by multifactorial degeneration of the optic nerve axons and retinal ganglion cells (RGCs), resulting in the loss of vision. Major components of glaucoma pathogenesis include glia-driven neuroinflammation and impairment of mitochondrial dynamics and bioenergetics, leading to retinal neurodegeneration. In this review article, we summarize current evidence for the emerging role of apolipoprotein A-I binding protein (AIBP) as an important anti-inflammatory and neuroprotective factor in the retina. Due to its association with toll-like receptor 4 (TLR4), extracellular AIBP selectively removes excess cholesterol from the plasma membrane of inflammatory and activated cells. This results in the reduced expression of TLR4-associated, cholesterol-rich lipid rafts and the inhibition of downstream inflammatory signaling. Intracellular AIBP is localized to mitochondria and modulates mitophagy through the ubiquitination of mitofusins 1 and 2. Importantly, elevated intraocular pressure induces AIBP deficiency in mouse models and in human glaucomatous retina. AIBP deficiency leads to the activation of TLR4 in Müller glia, triggering mitochondrial dysfunction in both RGCs and Müller glia, and compromising visual function in a mouse model. Conversely, restoring AIBP expression in the retina reduces neuroinflammation, prevents RGCs death, and protects visual function. These results provide new insight into the mechanism of AIBP function in the retina and suggest a therapeutic potential for restoring retinal AIBP expression in the treatment of glaucoma.


Assuntos
Glaucoma , Receptor 4 Toll-Like , Camundongos , Animais , Humanos , Receptor 4 Toll-Like/metabolismo , Doenças Neuroinflamatórias , Glaucoma/metabolismo , Retina/metabolismo , Colesterol/metabolismo
3.
Sensors (Basel) ; 23(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38139491

RESUMO

Trampolines are recognized as a valuable tool in exercise and rehabilitation due to their unique properties like elasticity, rebound force, low-impact exercise, and enhancement of posture, balance, and cardiopulmonary function. To quantitatively assess the effects of trampoline exercises, it is essential to estimate factors such as stiffness, elements influencing jump dynamics, and user safety. Previous studies assessing trampoline characteristics had limitations in performing repetitive experiments at various locations on the trampoline. Therefore, this research introduces a robotic system equipped with foot-shaped jigs to evaluate trampoline stiffness and quantitatively measure exercise effects. This system, through automated, repetitive movements at various locations on the trampoline, accurately measures the elastic coefficient and vertical forces. The robot maneuvers based on the coordinates of the trampoline, as determined by its torque and position sensors. The force sensor measures data related to the force exerted, along with the vertical force data at X, Y, and Z coordinates. The model's accuracy was evaluated using linear regression based on Hooke's Law, with Mean Absolute Error (MAE), Root Mean Square Error (RMSE), and Correlation Coefficient Squared (R-squared) metrics. In the analysis including only the distance between X and the foot-shaped jigs, the average MAE, RMSE, and R-squared values were 17.9702, 21.7226, and 0.9840, respectively. Notably, expanding the model to include distances in X, Y, and between the foot-shaped jigs resulted in a decrease in MAE to 15.7347, RMSE to 18.8226, and an increase in R-squared to 0.9854. The integrated model, including distances in X, Y, and between the foot-shaped jigs, showed improved predictive capability with lower MAE and RMSE and higher R-squared, indicating its effectiveness in more accurately predicting trampoline dynamics, vital in fitness and rehabilitation fields.


Assuntos
Procedimentos Cirúrgicos Robóticos , Extremidade Inferior , Exercício Físico , , Modelos Lineares
4.
Sensors (Basel) ; 23(24)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38139599

RESUMO

This paper proposes fault diagnosis methods aimed at proactively preventing potential safety issues in robot systems, particularly human coexistence robots (HCRs) used in industrial environments. The data were collected from durability tests of the driving module for HCRs, gathering time-series vibration data until the module failed. In this study, to apply classification methods in the absence of post-failure data, the initial 50% of the collected data were designated as the normal section, and the data from the 10 h immediately preceding the failure were selected as the fault section. To generate additional data for the limited fault dataset, the Wasserstein generative adversarial networks with gradient penalty (WGAN-GP) model was utilized and residual connections were added to the generator to maintain the basic structure while preventing the loss of key features of the data. Considering that the performance of image encoding techniques varies depending on the dataset type, this study applied and compared five image encoding methods and four CNN models to facilitate the selection of the most suitable algorithm. The time-series data were converted into image data using image encoding techniques including recurrence plot, Gramian angular field, Markov transition field, spectrogram, and scalogram. These images were then applied to CNN models, including VGGNet, GoogleNet, ResNet, and DenseNet, to calculate the accuracy of fault diagnosis and compare the performance of each model. The experimental results demonstrated significant improvements in diagnostic accuracy when employing the WGAN-GP model to generate fault data, and among the image encoding techniques and convolutional neural network models, spectrogram and DenseNet exhibited superior performance, respectively.

5.
bioRxiv ; 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-37905114

RESUMO

Glaucoma is a neurodegenerative disease manifested in retinal ganglion cell (RGC) death and irreversible blindness. While lowering intraocular pressure (IOP) is the only proven therapeutic strategy in glaucoma, it is insufficient for preventing disease progression, thus justifying the recent focus on targeting retinal neuroinflammation and preserving RGCs. We have identified apolipoprotein A-I binding protein (AIBP) as the protein regulating several mechanisms of retinal neurodegeneration. AIBP controls excessive cholesterol accumulation via upregulating the cholesterol transporter ATP-binding cassette transporter 1 (ABCA1) and reduces inflammatory signaling via toll-like receptor 4 (TLR4) and mitochondrial dysfunction. ABCA1, TLR4 and oxidative phosphorylation components are genetically linked to primary open-angle glaucoma. Here we demonstrated that AIBP and ABCA1 expression was decreased, while TLR4, interleukin 1 beta (IL-1 beta), and the cholesterol content increased in the retina of patients with glaucoma and in mouse models of glaucoma. Restoring AIBP expression by a single intravitreal injection of adeno-associated virus (AAV)-AIBP protected RGCs in glaucomatous DBA/2J mice, in mice with microbead-induced chronic IOP elevation, and optic nerve crush. In addition, AIBP expression attenuated TLR4 and IL-1 beta expression, localization of TLR4 to lipid rafts, reduced cholesterol accumulation, and ameliorated visual dysfunction. These studies collectively indicate that restoring AIBP expression in the glaucomatous retina reduces neuroinflammation and protects RGCs and Muller glia, suggesting the therapeutic potential of AAV-AIBP in human glaucoma.

6.
Exp Neurobiol ; 32(4): 302-312, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37749930

RESUMO

Cerebral ischemia can lead to a range of sequelae, including depression. The pathogenesis of depression involves neuronal change of the medial prefrontal cortex (mPFC). However, how cerebral ischemia-induced changes manifest across subregions and layers of the mPFC is not well understood. In this study, we induced cerebral ischemia in mice via transient bilateral common carotid artery occlusion (tBCCAO) and observed depressive-like behavior. Using whole-cell patch clamp recording, we identified changes in the excitability of pyramidal neurons in the prelimbic cortex (PL) and infralimbic cortex (IL), the subregions of mPFC. Compared to sham control mice, tBCCAO mice showed significantly reduced neuronal excitability in IL layer 2/3 but not layer 5 pyramidal neurons, accompanied by increased rheobase current and decreased input resistance. In contrast, no changes were observed in the excitability of PL layer 2/3 and layer 5 pyramidal neurons. Our results provide a new direction for studying the pathogenesis of depression following ischemic damage by showing that cerebral ischemia induces subregion- and layer-specific changes in the mPFC pyramidal neurons.

7.
Exp Mol Med ; 55(8): 1783-1794, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37524878

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder associated with impaired social behavior and communication, repetitive behaviors, and restricted interests. In addition to genetic factors, environmental factors such as prenatal drug exposure contribute to the development of ASD. However, how those prenatal factors induce behavioral deficits in the adult stage is not clear. To elucidate ASD pathogenesis at the molecular level, we performed a high-resolution mass spectrometry-based quantitative proteomic analysis on the prefrontal cortex (PFC) of mice exposed to valproic acid (VPA) in utero, a widely used animal model of ASD. Differentially expressed proteins (DEPs) in VPA-exposed mice showed significant overlap with ASD risk genes, including differentially expressed genes from the postmortem cortex of ASD patients. Functional annotations of the DEPs revealed significant enrichment in the Wnt/ß-catenin signaling pathway, which is dysregulated by the upregulation of Rnf146 in VPA-exposed mice. Consistently, overexpressing Rnf146 in the PFC impaired social behaviors and altered the Wnt signaling pathway in adult mice. Furthermore, Rnf146-overexpressing PFC neurons showed increased excitatory synaptic transmission, which may underlie impaired social behavior. These results demonstrate that Rnf146 is critical for social behavior and that dysregulation of Rnf146 underlies social deficits in VPA-exposed mice.


Assuntos
Transtorno do Espectro Autista , Ubiquitina-Proteína Ligases , Via de Sinalização Wnt , Animais , Feminino , Camundongos , Gravidez , Transtorno do Espectro Autista/induzido quimicamente , Transtorno do Espectro Autista/genética , Modelos Animais de Doenças , Proteômica , Ubiquitina-Proteína Ligases/metabolismo , Regulação para Cima , Ácido Valproico/efeitos adversos
8.
Cells ; 12(11)2023 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-37296658

RESUMO

A-Kinase anchoring protein 1 (AKAP1) is a multifunctional mitochondrial scaffold protein that regulates mitochondrial dynamics, bioenergetics, and calcium homeostasis by anchoring several proteins, including protein kinase A, to the outer mitochondrial membrane. Glaucoma is a complex, multifactorial disease characterized by a slow and progressive degeneration of the optic nerve and retinal ganglion cells (RGCs), ultimately resulting in vision loss. Impairment of the mitochondrial network and function is linked to glaucomatous neurodegeneration. Loss of AKAP1 induces dynamin-related protein 1 dephosphorylation-mediated mitochondrial fragmentation and loss of RGCs. Elevated intraocular pressure triggers a significant reduction in AKAP1 protein expression in the glaucomatous retina. Amplification of AKAP1 expression protects RGCs from oxidative stress. Hence, modulation of AKAP1 could be considered a potential therapeutic target for neuroprotective intervention in glaucoma and other mitochondria-associated optic neuropathies. This review covers the current research on the role of AKAP1 in the maintenance of mitochondrial dynamics, bioenergetics, and mitophagy in RGCs and provides a scientific basis to identify and develop new therapeutic strategies that could protect RGCs and their axons in glaucoma.


Assuntos
Glaucoma , Células Ganglionares da Retina , Humanos , Células Ganglionares da Retina/metabolismo , Proteínas de Ancoragem à Quinase A/metabolismo , Neuroproteção , Glaucoma/metabolismo , Retina/metabolismo
9.
Data Brief ; 45: 108605, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36426006

RESUMO

In this paper, we present a dataset to be used for the construction of the Voronoi diagram of 3D spherical balls (VD-B3). The dataset consists of sphere arrangements including general, anomaly, and extreme cases. The dataset also includes protein models downloaded from RCSB Protein Data Bank (PDB). The dataset can be used as a standard benchmark dataset to verify and validate the correctness, efficiency, and robustness of the construction algorithm. The dataset is simple and easy to understand. The details of the experiment and analysis based on this dataset are presented in the original research article: "Robust Construction of the Voronoi Diagram of Spherical Balls in the Three-Dimensional Space" which introduces the topology-oriented incremental algorithm for the construction that is thoroughly validated and compared with two implementations of the well known edge-tracing algorithm.

10.
Cells ; 11(19)2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36230988

RESUMO

Vascular cognitive impairment (VCI) is a common sequela of cerebrovascular disorders. Although transcutaneous auricular vagus nerve stimulation (taVNS) has been considered a complementary treatment for various cognitive disorders, preclinical data on the effect of taVNS on VCI and its mechanism remain ambiguous. To measure cerebrospinal fluid (CSF) circulation during taVNS, we used in vivo two-photon microscopy with CSF and vasculature tracers. VCI was induced by transient bilateral common carotid artery occlusion (tBCCAO) surgery in mice. The animals underwent anesthesia, off-site stimulation, or taVNS for 20 min. Cognitive tests, including the novel object recognition and the Y-maze tests, were performed 24 h after the last treatment. The long-term treatment group received 6 days of treatment and was tested on day 7; the short-term treatment group received 2 days of treatment and was tested 3 days after tBCCAO surgery. CSF circulation increased remarkably in the taVNS group, but not in the anesthesia-control or off-site-stimulation-control groups. The cognitive impairment induced by tBCCAO was significantly restored after both long- and short-term taVNS. In terms of effects, both long- and short-term stimulations showed similar recovery effects. Our findings provide evidence that taVNS can facilitate CSF circulation and that repetitive taVNS can ameliorate VCI symptoms.


Assuntos
Disfunção Cognitiva , Estimulação Elétrica Nervosa Transcutânea , Estimulação do Nervo Vago , Animais , Cognição , Disfunção Cognitiva/terapia , Camundongos , Roedores
11.
Nat Commun ; 13(1): 6303, 2022 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-36272977

RESUMO

Regulated in development and DNA damage response 1 (REDD1) expression is upregulated in response to metabolic imbalance and obesity. However, its role in obesity-associated complications is unclear. Here, we demonstrate that the REDD1-NF-κB axis is crucial for metabolic inflammation and dysregulation. Mice lacking Redd1 in the whole body or adipocytes exhibited restrained diet-induced obesity, inflammation, insulin resistance, and hepatic steatosis. Myeloid Redd1-deficient mice showed similar results, without restrained obesity and hepatic steatosis. Redd1-deficient adipose-derived stem cells lost their potential to differentiate into adipocytes; however, REDD1 overexpression stimulated preadipocyte differentiation and proinflammatory cytokine expression through atypical IKK-independent NF-κB activation by sequestering IκBα from the NF-κB/IκBα complex. REDD1 with mutated Lys219/220Ala, key amino acid residues for IκBα binding, could not stimulate NF-κB activation, adipogenesis, and inflammation in vitro and prevented obesity-related phenotypes in knock-in mice. The REDD1-atypical NF-κB activation axis is a therapeutic target for obesity, meta-inflammation, and metabolic complications.


Assuntos
Fígado Gorduroso , NF-kappa B , Camundongos , Animais , NF-kappa B/metabolismo , Inibidor de NF-kappaB alfa/genética , Obesidade/complicações , Obesidade/genética , Obesidade/metabolismo , Inflamação/metabolismo , Fígado Gorduroso/metabolismo , Citocinas , Aminoácidos
12.
Sensors (Basel) ; 22(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36146261

RESUMO

In the wake of COVID-19, the digital fitness market combining health equipment and ICT technologies is experiencing unexpected high growth. A smart trampoline fitness system is a new representative home exercise equipment for muscle strengthening and rehabilitation exercises. Recognizing the motions of the user and evaluating user activity is critical for implementing its self-guided exercising system. This study aimed to estimate the three-dimensional positions of the user's foot using deep learning-based image processing algorithms for footprint shadow images acquired from the system. The proposed system comprises a jumping fitness trampoline; an upward-looking camera with a wide-angle and fish-eye lens; and an embedded board to process deep learning algorithms. Compared with our previous approach, which suffered from a geometric calibration process, a camera calibration method for highly distorted images, and algorithmic sensitivity to environmental changes such as illumination conditions, the proposed deep learning algorithm utilizes end-to-end learning without calibration. The network is configured with a modified Fast-RCNN based on ResNet-50, where the region proposal network is modified to process location regression different from box regression. To verify the effectiveness and accuracy of the proposed algorithm, a series of experiments are performed using a prototype system with a robotic manipulator to handle a foot mockup. The three root mean square errors corresponding to X, Y, and Z directions were revealed to be 8.32, 15.14, and 4.05 mm, respectively. Thus, the system can be utilized for motion recognition and performance evaluation of jumping exercises.


Assuntos
COVID-19 , Aprendizado Profundo , Algoritmos , Calibragem , Humanos , Processamento de Imagem Assistida por Computador/métodos
13.
Biomed Pharmacother ; 134: 111110, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33338749

RESUMO

Targeting the vascular endothelial growth factor (VEGF)/its receptor-2 (VEGFR-2) system has become a mainstay of treatment for many human diseases, including retinal diseases. We examined the therapeutic effect of recently developed N-acetylated Arg-Leu-Tyr-Glu (Ac-RLYE), a human plasminogen kringle-5 domain-derived VEGFR-2 antagonists, on the pathogenesis of diabetic retinopathy. Ac-RLYE inhibited VEGF-A-mediated VEGFR-2 activation and endothelial nitric oxide synthase (eNOS)-derived NO production in the retinas of diabetic mice. In addition, Ac-RLYE prevented the disruption of adherens and tight junctions and vascular leakage by inhibiting S-nitrosylation of ß-catenin and tyrosine nitration of p190RhoGAP in the retinal vasculature of diabetic mice. Peptide treatment preserved the pericyte coverage of retinal capillaries by upregulating angiopoietin-2. These results suggest that Ac-RLYE potentially prevents blood-retinal barrier breakdown and vascular leakage by antagonizing VEGFR-2; Ac-RLYE can be used as a potential therapeutic drug for the treatment of diabetic retinopathy.


Assuntos
Inibidores da Angiogênese/farmacologia , Barreira Hematorretiniana/efeitos dos fármacos , Retinopatia Diabética/tratamento farmacológico , Oligopeptídeos/farmacologia , Vasos Retinianos/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Junções Aderentes/efeitos dos fármacos , Junções Aderentes/metabolismo , Junções Aderentes/patologia , Animais , Barreira Hematorretiniana/metabolismo , Barreira Hematorretiniana/patologia , Permeabilidade Capilar/efeitos dos fármacos , Células Cultivadas , Diabetes Mellitus Experimental/complicações , Retinopatia Diabética/etiologia , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Humanos , Masculino , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Vasos Retinianos/metabolismo , Vasos Retinianos/patologia , Transdução de Sinais , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Junções Íntimas/patologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
14.
Exp Mol Med ; 52(8): 1298-1309, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32770080

RESUMO

Endothelial progenitor cell (EPC) dysfunction impairs vascular function and remodeling in inflammation-associated diseases, including preeclampsia. However, the underlying mechanism of this inflammation-induced dysfunction remains unclear. In the present study, we found increases in TNF-α and miR-31/155 levels and reduced numbers of circulating EPCs in patients with preeclampsia. Patient-derived mononuclear cells (MNCs) cultured in autologous serum had decreased endothelial nitric oxide synthase (eNOS) expression, nitric oxide production, and differentiation into EPCs with angiogenic potential, and these effects were inhibited by a TNF-α-neutralizing antibody and miR-31/155 inhibitors. Moreover, TNF-α treatment of normal MNCs increased miR-31/155 biogenesis, decreased eNOS expression, reduced EPC differentiation, and impaired angiogenic potential. The TNF-α-induced impairment of EPC differentiation and function was rescued by NF-κB p65 knockdown or miR-31/155 inhibitors. In addition, treatment of MNCs with synthetic miR-31/155 or an eNOS inhibitor mimicked the inhibitory effects of TNF-α on eNOS expression and EPC functions. Moreover, transplantation of EPCs that had been differentiated from TNF-α-treated MNCs decreased neovascularization and blood perfusion in ischemic mouse hindlimbs compared with those of normally differentiated EPCs. These findings suggest that NF-κB activation is required for TNF-α-induced impairment of EPC mobilization, differentiation, and function via miR-31/155 biogenesis and eNOS downregulation. Our data provide a new role for NF-κB-dependent miR-31/155 in EPC dysfunction under the pathogenic conditions of inflammation-associated vascular diseases, including preeclampsia.


Assuntos
Células Progenitoras Endoteliais/metabolismo , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Diferenciação Celular/genética , Regulação para Baixo/genética , Células Progenitoras Endoteliais/patologia , Feminino , Membro Posterior/irrigação sanguínea , Humanos , Isquemia/patologia , Masculino , Camundongos Nus , MicroRNAs/sangue , MicroRNAs/genética , Neovascularização Fisiológica/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/genética , Gravidez , Fator de Necrose Tumoral alfa/sangue
15.
Mol Pharmacol ; 96(6): 692-701, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31594790

RESUMO

The tetrapeptide Arg-Leu-Tyr-Glu (RLYE), a vascular endothelial growth factor (VEGF) receptor-2 antagonist, has been used previously either alone or in combination with chemotherapeutic drugs for treating colorectal cancer in a mouse model. We analyzed the half-life of the peptide and found that because of degradation by aminopeptidases B and N, it had a short half-life of 1.2 hours in the serum. Therefore, to increase the stability and potency of the peptide, we designed the modified peptide, N-terminally acetylated RLYE (Ac-RLYE), which had a strongly stabilized half-life of 8.8 hours in serum compared with the original parent peptide. The IC50 value of Ac-RLYE for VEGF-A-induced endothelial cell migration decreased to approximately 37.1 pM from 89.1 pM for the parent peptide. Using a mouse xenograft tumor model, we demonstrated that Ac-RLYE was more potent than RLYE in inhibiting tumor angiogenesis and growth, improving vascular integrity and normalization through enhanced endothelial cell junctions and pericyte coverage of the tumor vasculature, and impeding the infiltration of macrophages into tumor and their polarization to the M2 phenotype. Furthermore, combined treatment of Ac-RLYE and irinotecan exhibited synergistic effects on M1-like macrophage activation and apoptosis and growth inhibition of tumor cells. These findings provide evidence that the N-terminal acetylation augments the therapeutic effect of RLYE in solid tumors via inhibition of tumor angiogenesis, improvement of tumor vessel integrity and normalization, and enhancement of the livery and efficacy of the coadministered chemotherapeutic drugs. SIGNIFICANCE STATEMENT: The results of this study demonstrate that the N-terminal acetylation of the tetrapeptide RLYE (Ac-RLYE), a novel vascular endothelial growth factor receptor-2 (VEGFR-2) inhibitor, significantly improves its serum stability, antiangiogenic activity, and vascular normalizing potency, resulting in enhanced therapeutic effect on solid tumors. Furthermore, the combined treatment of Ac-RLYE with the chemotherapeutic drug, irinotecan, synergistically enhanced its antitumor efficacy by improving the perfusion and delivery of the drug into the tumors and stimulating the conversion of the tumor-associated macrophages to an immunostimulatory M1-like antitumor phenotype.


Assuntos
Antineoplásicos/administração & dosagem , Neovascularização Patológica/sangue , Neovascularização Patológica/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Peptídeo Hidrolases/sangue , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Células HCT116 , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Nus , Estabilidade Proteica/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
16.
Toxins (Basel) ; 11(7)2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31288453

RESUMO

Oxaliplatin is a chemotherapeutic agent used for metastatic colon and other advanced cancers. Most common side effect of oxaliplatin is peripheral neuropathy, manifested in mechanical and cold allodynia. Although the analgesic effect of bee venom has been proven to be effective against oxaliplatin-induced peripheral neuropathy, the effect of its major component; melittin has not been studied yet. Thus, in this study, we investigated whether melittin has an analgesic effect on oxaliplatin-induced allodynia. Intraperitoneal single injection of oxaliplatin (6 mg/kg) induced mechanical and cold allodynia, resulting in increased withdrawal behavior in response to von Frey filaments and acetone drop on hind paw. Subcutaneous melittin injection on acupoint ST36 (0.5 mg/kg) alleviated oxaliplatin-induced mechanical and cold allodynia. In electrophysiological study, using spinal in vivo extracellular recording, it was shown that oxaliplatin-induced hyperexcitation of spinal wide dynamic range neurons in response to peripheral stimuli, and melittin administration inhibited this neuronal activity. In behavioral assessment, analgesic effect of melittin was blocked by intrathecal α1- and α2- adrenergic receptor antagonists administration. Based on these results, we suggest that melittin could be used as an analgesic on oxaliplatin-induced peripheral neuropathy, and that its effect is mediated by activating the spinal α1- and α2-adrenergic receptors.


Assuntos
Analgésicos/uso terapêutico , Hiperalgesia/tratamento farmacológico , Meliteno/uso terapêutico , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 2/farmacologia , Analgésicos/farmacologia , Animais , Antineoplásicos , Temperatura Baixa , Hiperalgesia/induzido quimicamente , Idazoxano/farmacologia , Meliteno/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Oxaliplatina , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Prazosina/farmacologia , Ratos Sprague-Dawley , Receptores Adrenérgicos alfa 1/fisiologia , Receptores Adrenérgicos alfa 2/fisiologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/fisiologia , Tato
17.
Biomol Ther (Seoul) ; 27(5): 474-483, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31042676

RESUMO

Vascular endothelial growth factor (VEGF) plays a pivotal role in pathologic ocular neovascularization and vascular leakage via activation of VEGF receptor 2 (VEGFR2). This study was undertaken to evaluate the therapeutic mechanisms and effects of the tetrapeptide Arg-Leu-Tyr-Glu (RLYE), a VEGFR2 inhibitor, in the development of vascular permeability and choroidal neovascularization (CNV). In cultured human retinal microvascular endothelial cells (HRMECs), treatment with RLYE blocked VEGF-A-induced phosphorylation of VEGFR2, Akt, ERK, and endothelial nitric oxide synthase (eNOS), leading to suppression of VEGFA-mediated hyper-production of NO. Treatment with RLYE also inhibited VEGF-A-stimulated angiogenic processes (migration, proliferation, and tube formation) and the hyperpermeability of HRMECs, in addition to attenuating VEGF-A-induced angiogenesis and vascular permeability in mice. The anti-vascular permeability activity of RLYE was correlated with enhanced stability and positioning of the junction proteins VE-cadherin, ß-catenin, claudin-5, and ZO-1, critical components of the cortical actin ring structure and retinal endothelial barrier, at the boundary between HRMECs stimulated with VEGF-A. Furthermore, intravitreally injected RLYE bound to retinal microvascular endothelium and inhibited laser-induced CNV in mice. These findings suggest that RLYE has potential as a therapeutic drug for the treatment of CNV by preventing VEGFR2-mediated vascular leakage and angiogenesis.

18.
Exp Mol Med ; 51(2): 1-12, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30765689

RESUMO

Vascular smooth muscle cells (VSMCs) play an important role in maintaining vascular function. Inflammation-mediated VSMC dysfunction leads to atherosclerotic intimal hyperplasia and preeclamptic hypertension; however, the underlying mechanisms are not clearly understood. We analyzed the expression levels of microRNA-155 (miR-155) in cultured VSMCs, mouse vessels, and clinical specimens and then assessed its role in VSMC function. Treatment with tumor necrosis factor-α (TNF-α) elevated miR-155 biogenesis in cultured VSMCs and vessel segments, which was prevented by NF-κB inhibition. MiR-155 expression was also increased in high-fat diet-fed ApoE-/- mice and in patients with atherosclerosis and preeclampsia. The miR-155 levels were inversely correlated with soluble guanylyl cyclase ß1 (sGCß1) expression and nitric oxide (NO)-dependent cGMP production through targeting the sGCß1 transcript. TNF-α-induced miR-155 caused VSMC phenotypic switching, which was confirmed by the downregulation of VSMC-specific marker genes, suppression of cell proliferation and migration, alterations in cell morphology, and NO-induced vasorelaxation. These events were mitigated by miR-155 inhibition. Moreover, TNF-α did not cause VSMC phenotypic modulation and limit NO-induced vasodilation in aortic vessels of miR-155-/- mice. These findings suggest that NF-κB-induced miR-155 impairs the VSMC contractile phenotype and NO-mediated vasorelaxation by downregulating sGCß1 expression. These data suggest that NF-κB-responsive miR-155 is a novel negative regulator of VSMC functions by impairing the sGC/cGMP pathway, which is essential for maintaining the VSMC contractile phenotype and vasorelaxation, offering a new therapeutic target for the treatment of atherosclerosis and preeclampsia.


Assuntos
MicroRNAs/genética , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , NF-kappa B/metabolismo , Guanilil Ciclase Solúvel/metabolismo , Animais , GMP Cíclico/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Knockout , Óxido Nítrico/metabolismo , Fenótipo , Interferência de RNA , Guanilil Ciclase Solúvel/genética , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
19.
RSC Adv ; 9(10): 5731-5737, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35515898

RESUMO

Scientific and technological advances in transparent conductive electrodes improve the heating performance of flexible transparent film heaters (TFHs), which can be utilized for various applications as defrosters and heaters. To achieve high performance as well as practical TFHs, several conditions, such as high optical transmittance, low electrical resistance, heating uniformity, and operational stability in various environmental conditions should be satisfied. However, due to the trade-offs between optical transmittance and electrical resistance, it is not easy to fulfill all the requirements concurrently. Here we report flexible TFHs using a ternary composite of silver nanowire (AgNW), conducting polymer (i.e., poly[3,4-ethylenedioxythiophene]:polystyrene sulfonate [PEDOT:PSS]), and a thin conductive oxide (i.e., indium tin oxide [ITO]) layer, exhibiting higher performance in terms of the maximum heating temperature (>110 °C), operational stability, mechanical flexibility, and optical transmittance (95% at 550 nm), compared to pristine AgNW-based TFHs. We also demonstrated the stable operation of the AgNW-PEDOT:PSS/ITO TFHs soaked in water, showing excellent environmental stability. To analyse the fundamental mechanisms for the improved performance of the AgNW-PEDOT:PSS/ITO TFHs, we investigated the progress of joule heating using a device simulator, and found that the improvement originated not only from reduced electrical resistance but also from enhanced heat dissipation with PEDOT:PSS and ITO. We anticipate that our analysis and results will be helpful for further development of practical flexible TFHs.

20.
J Biol Chem ; 293(49): 18989-19000, 2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30279269

RESUMO

Inflammatory cytokines, including tumor necrosis factor-α (TNFα), were elevated in patients with cardiovascular diseases and are also considered as crucial factors in the pathogenesis of preeclampsia; however, the underlying pathogenic mechanism has not been clearly elucidated. This study provides novel evidence that TNFα leads to endothelial dysfunction associated with hypertension and vascular remodeling in preeclampsia through down-regulation of endothelial nitric-oxide synthase (eNOS) by NF-κB-dependent biogenesis of microRNA (miR)-31-5p, which targets eNOS mRNA. In this study, we found that miR-31-5p was up-regulated in sera from patients with preeclampsia and in human endothelial cells treated with TNFα. TNFα-mediated induction of miR-31-5p was blocked by an NF-κB inhibitor and NF-κB p65 knockdown but not by mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase inhibitors, indicating that NF-κB is essential for biogenesis of miR-31-5p. The treatment of human endothelial cells with TNFα or miR-31-5p mimics decreased endothelial nitric-oxide synthase (eNOS) mRNA stability without affecting eNOS promoter activity, resulting in inhibition of eNOS expression and NO/cGMP production through blocking of the functional activity of the eNOS mRNA 3'-UTR. Moreover, TNFα and miR-31-5p mimic evoked endothelial dysfunction associated with defects in angiogenesis, trophoblastic invasion, and vasorelaxation in an ex vivo cultured model of human placental arterial vessels, which are typical features of preeclampsia. These results suggest that NF-κB-responsive miR-31-5p elicits endothelial dysfunction, hypertension, and vascular remodeling via post-transcriptional down-regulation of eNOS and is a molecular risk factor in the pathogenesis and development of preeclampsia.


Assuntos
Células Endoteliais/fisiologia , MicroRNAs/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Pré-Eclâmpsia/metabolismo , Regiões 3' não Traduzidas/genética , Animais , Artérias/efeitos dos fármacos , Regulação para Baixo , Células Endoteliais/efeitos dos fármacos , Feminino , Técnicas de Silenciamento de Genes , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/farmacologia , Subunidade p50 de NF-kappa B/genética , Subunidade p50 de NF-kappa B/metabolismo , Neovascularização Fisiológica , Placenta/irrigação sanguínea , Placenta/efeitos dos fármacos , Pré-Eclâmpsia/genética , Gravidez , Trofoblastos/fisiologia , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
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