Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Opt Express ; 31(5): 8650-8667, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36859976

RESUMO

Multispectral stealth technology including terahertz (THz) band will play an increasingly important role in modern military and civil applications. Here, based on the concept of modularization design, two kinds of flexible and transparent metadevices were fabricated for multispectral stealth, covering the visible, infrared (IR), THz, and microwave bands. First, three basic functional blocks for IR, THz, and microwave stealth are designed and fabricated by using flexible and transparent films. And then, via modular assembling, that is, by adding or removing some stealth functional blocks or constituent layers, two multispectral stealth metadevices are readily achieved. Metadevice 1 exhibits THz-microwave dual-band broadband absorption, with average measured absorptivity of 85% in 0.3-1.2 THz and higher than 90% in 9.1-25.1 GHz, suitable for THz-microwave bi-stealth. Metadevice 2 is for IR and microwave bi-stealth, with measured absorptivity higher than 90% in 9.7-27.3 GHz and low emissivity around 0.31 in 8-14 µm. Both metadevices are optically transparent and able to maintain good stealth ability under curved and conformal conditions. Our work offers an alternative approach for designing and fabricating flexible transparent metadevices for multispectral stealth, especially for applications in nonplanar surfaces.

2.
Pharmacol Res ; 194: 106840, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37379961

RESUMO

Dysregulated mitochondrial metabolism occurs in several pathological processes characterized by cell proliferation and migration. Nonetheless, the role of mitochondrial fission is not well appreciated in cardiac fibrosis, which is accompanied by enhanced fibroblast proliferation and migration. We investigated the causes and consequences of mitochondrial fission in cardiac fibrosis using cultured cells, animal models, and clinical samples. Increased METTL3 expression caused excessive mitochondrial fission, resulting in the proliferation and migration of cardiac fibroblasts that lead to cardiac fibrosis. Knockdown of METTL3 suppressed mitochondrial fission, inhibiting fibroblast proliferation and migration for ameliorating cardiac fibrosis. Elevated METTL3 and N6-methyladenosine (m6A) levels were associated with low expression of long non-coding RNA GAS5. Mechanistically, METTL3-mediated m6A methylation of GAS5 induced its degradation, dependent of YTHDF2. GAS5 could interact with mitochondrial fission marker Drp1 directly; overexpression of GAS5 suppressed Drp1-mediated mitochondrial fission, inhibiting cardiac fibroblast proliferation and migration. Knockdown of GAS5 produced the opposite effect. Clinically, increased METTL3 and YTHDF2 levels corresponded with decreased GAS5 expression, increased m6A mRNA content and mitochondrial fission, and increased cardiac fibrosis in human heart tissue with atrial fibrillation. We describe a novel mechanism wherein METTL3 boosts mitochondrial fission, cardiac fibroblast proliferation, and fibroblast migration: METTL3 catalyzes m6A methylation of GAS5 methylation in a YTHDF2-dependent manner. Our findings provide insight into the development of preventative measures for cardiac fibrosis.


Assuntos
Metiltransferases , Dinâmica Mitocondrial , RNA Longo não Codificante , Animais , Humanos , Fibrose , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Fatores de Transcrição/metabolismo , Camundongos
3.
Opt Express ; 30(5): 7694-7707, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35299525

RESUMO

Electromagnetic multipoles enable rich electromagnetic interactions in a metasurface and offer another degree of freedom to control electromagnetic responses. In this work, we design and experimentally demonstrate an optically transparent, flexible and broadband microwave metasurface absorber based on multipolar interference engineering. Different from previous works, the designed metasurface simultaneously supports fundamental electric dipole and high-order electric quadrupole mode, whose interference satisfies the back-scattering suppression condition based on the generalized Kerker effect and thus high absorption. The measurement results indicate that the fabricated metasurface exhibits a high average absorption of 89% in the microwave band from 4 GHz to 18 GHz, together with a good optical transparency. Our study offers an alternative approach for designing broadband microwave metasurface absorber, which is potentially applicable in electromagnetic shielding, radar stealth and energy harvesting.

4.
Opt Express ; 29(16): 25709-25719, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34614894

RESUMO

Metasurfaces have shown extraordinary light-manipulation abilities, however, most of them deal with free-space waves. It is highly desirable to develop a guided wave-driven metasurface which can extract the in-plane guided modes in the waveguide and mold it into the desired out-of-plane free-space modes. In this paper, an all-dielectric guided wave-driven metasurface, composed of an array of silicon meta-atoms on top of a silicon nitride waveguide, is proposed and simulatively demonstrated. When directly driven by fundamental transverse electric (TE00) and fundamental transverse magnetic (TM00) guided modes at operation wavelength 1.55 µm, the guided wave-driven metasurface converts them into y-polarized and x-polarized free-space light, respectively, and focuses them at different focal points, with polarization extinction ratio over 27 dB, thus simultaneously realizing triple functions of coupling guided modes to free-space waves, bifocal metalens and polarization demultiplexing. Our work offers an alternate way to control light across photonic integrated devices and free-space platforms.

5.
Opt Express ; 29(8): 12580-12589, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33985012

RESUMO

The analogue of electromagnetically induced transparency (EIT-like) and electromagnetically induced reflectance (EIR-like) effects have been intensively studied and achieved by using metasurfaces. Nevertheless, previous designs could realize only one of them and were unable to support both effects in a metasurface. Here we numerically and experimentally demonstrate a metasurface simultaneously exhibiting EIT-like and EIR-like effects. Qualitative analyses and quantitative calculations based on the electromagnetic multipole decomposition method are performed to reveal their formation mechanisms. Our work offers a simple avenue for simultaneously realizing EIT-like and EIR-like effects in a metasurface, which may find potential applications in sensing, filtering, and slow wave devices.

6.
Opt Express ; 28(22): 32721-32737, 2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33114951

RESUMO

Compact and planar optical beam splitters are highly desirable in various optical and photonic applications. Here, we investigate two kinds of optical beam splitters by using oligomer-based metasurfaces, one is trimer-based metasurface for 3-dB beam splitting, and the other is pentamer-based metasurface for 1:4 beam splitting. Through electromagnetic multipole decomposition and in-depth mechanism analyses, we reveal that the electromagnetic multipolar interactions and the strong near-field coupling between neighboring nanoparticles play critical roles in beam-splitting performance. Our work offers a deeper understanding of electromagnetic coupling effect in oligomer-based metasurfaces, and provides an alternative approach to planar beam splitters.

7.
Opt Express ; 28(20): 29496-29512, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33114849

RESUMO

We design and fabricate a double-layered chiral metamaterial with 4-fold rotational symmetry, which simultaneously exhibits optical rotation and electromagnetically induced transparency (EIT) effects. Using analytical equivalent circuit model and Lorentz's coupled oscillator model, we interpret the physical mechanisms and derive material equations. Importantly, we find that magnetic dipole and electric quadrupole play important roles in optical rotation and keeping the symmetry of the material equations. Our work offers a better understanding of optical rotation in chiral metamaterials, and provides a new and simple approach to combine optical rotation and EIT effects into a single metamaterial.

8.
Updates Surg ; 76(2): 495-503, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37698809

RESUMO

This study aims to assess the feasibility of the Overlap anastomosis technique in minimally invasive Ivor-Lewis esophagectomy. An accompanying video presentation elucidates our surgical procedures. A retrospective review of 46 patients diagnosed with middle and lower esophageal cancer was conducted. These patients underwent minimally invasive Ivor-Lewis esophagectomy with Overlap anastomosis between January 2019 and December 2020. A consistent team of surgeons performed all procedures. The initial phase involved laparoscopic stomach mobilization, intra-abdominal lymphadenectomies, and preparation of the tubular stomach. Subsequently, with the patient in the left decubitus position, thoracoscopy was used to dissect the esophagus, excise the diseased segment, and conduct mediastinal lymph node dissection. The final stage encompassed the intrathoracic gastroesophageal anastomosis using the Overlap method. All surgeries were completed without converting to an open approach, achieving complete resection. There were no operative fatalities, with an average surgery duration of 259.4 min. Average statistics included intraoperative blood loss of 92.3 ml, 16.2 lymph nodes dissected, and a postoperative hospital stay of 10.3 days. Postoperative complications comprised three instances of hoarseness due to recurrent laryngeal nerve palsy, two cases of aspiration pneumonia, one occurrence of chylothorax, and one gastric emptying disorder. Anastomotic technique-related complications were minimal, with only one patient experiencing an anastomotic leak that resolved spontaneously and two patients facing anastomotic stenosis, which was subsequently alleviated. Our findings posit that the Overlap anastomosis method is safe and efficient for minimally invasive Ivor-Lewis esophagectomy, marked by a notably low rate of anastomosis-related complications. Further evaluation of its long-term implications remains necessary.


Assuntos
Neoplasias Esofágicas , Laparoscopia , Humanos , Esofagectomia/métodos , Anastomose Cirúrgica/métodos , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/patologia , Complicações Pós-Operatórias/etiologia , Laparoscopia/métodos , Estudos Retrospectivos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos
9.
Nanoscale ; 15(32): 13335-13345, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37526575

RESUMO

Hybrid anapole state, originating from the destructive interference of more than one basic electromagnetic multipole moments with their toroidal counterparts, enables the simultaneous suppression of multiple leading scattering channels, thereby demonstrates promising applications in perfect absorption and electromagnetic camouflage. However, the formation of hybrid anapoles is challenging because a careful overlap of electromagnetic multipoles with their toroidal counterparts is required. In this study, we propose and experimentally demonstrate a transparent and flexible assembled metasurface rasorber supporting hybrid anapole states for infrared and microwave camouflage, which not only supports low IR emissivity in the range of 8-14 µm but also exhibits an absorption-transmission-absorption response in the microwave band. In addition, the conformal and tunable performances of the fabricated metasurface rasorber are experimentally demonstrated. Our study provides a new strategy for designing multispectral camouflage metasurfaces.

10.
Eur J Pharmacol ; 942: 175494, 2023 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-36657656

RESUMO

Cardiac fibrosis remains an unresolved problem in heart disease. Its etiology is directly caused by the activation and proliferation of cardiac fibroblasts (CFs). However, there is limited information regarding the biological role of cardiac fibroblasts in cardiac fibrosis. Herein, we screened out a gene, IGFBP3, whose expression significantly increased in TGF-ß1-stimulated human primary CFs by mining RNA-Seq data for differential and WGCNA. We verified the IGFBP3's expression in transverse aortic constriction (TAC) surgery, isoproterenol (ISO)-induced cardiac fibrosis models, and TGFß1-stimulated mouse primary CFs. We also found that the knockdown of IGFBP3 could inhibit the migration and proliferation ability of CFs. Furthermore, we found that aberrant N6-methyladenosine(m6A) mRNA modifications in the animal model and activated CFs may regulate the expression of IGFBP3 in developing cardiac fibrosis. Silencing METTL3 could downregulate the expression of IGFBP3 and inhibit the activation of CFs and the degree of cardiac fibrosis both in vitro and in vivo. Indeed, we also verified the expression of METTL3 and IGFBP3 in the atrial tissues of patients with atrial fibrillation (AF). Thus, METTL3 may regulate IGFBP3's expression and CFs activation via RNA epigenetic modifications, laying the foundation for a specific and novel therapeutic target in cardiac fibrosis.


Assuntos
Cardiomiopatias , Animais , Humanos , Camundongos , Cardiomiopatias/metabolismo , Proliferação de Células/genética , Epigênese Genética , Fibroblastos/metabolismo , Fibrose , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Metiltransferases/genética , Metiltransferases/metabolismo , Miocárdio/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
11.
Eur J Pharmacol ; 938: 175398, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36455647

RESUMO

Cardiac fibroblasts (CFs) drive extracellular matrix remodeling after inflammatory injury, leading to cardiac fibrosis and diastolic dysfunction. Recent studies described the role of epigenetics in cardiac fibrosis. Nevertheless, detailed reports on epigenetics regulating CFs pyroptosis and describing their implication in cardiac fibrosis are still unclear. Here, we found that DNMT3A reduces the expression of lncRNA Neat1 and promotes the NLRP3 axis leading to CFs pyroptosis, using cultured cells, animal models, and clinical samples to shed light on the underlying mechanism. We report that pyroptosis-related genes are increased explicitly in cardiac fibrosis tissue and LPS-treated CFs, while lncRNA Neat1 decreased. Mechanistically, we show that loss of DNMT3A or overexpression of lncRNA Neat1 in CFs after LPS treatment significantly enhances CFs pyroptosis and the production of pyroptosis-related markers in vitro. It has been demonstrated that DNMT3A can decrease lncRNA Neat1, promoting NLRP3 axis activation in CFs treated with LPS. In sum, this study is the first to identify that DNMT3A methylation decreases the expression of lncRNA Neat1 and promotes CFs pyroptosis and cardiac fibrosis, suggesting that DNMT3A and NEAT1 may function as an anti-fibrotic therapy target in cardiac fibrosis.


Assuntos
Cardiomiopatias , MicroRNAs , RNA Longo não Codificante , Animais , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Piroptose/genética , Lipopolissacarídeos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fibrose , Fibroblastos/metabolismo , Cardiomiopatias/metabolismo , Epigênese Genética , MicroRNAs/genética
12.
Front Oncol ; 12: 916907, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35785154

RESUMO

Growing evidence has shown the oncogenic function of matrix metallopeptidase 7 (MMP7) in various tumors. However, no systemic pan-cancer analysis on the association between MMP7 and different cancers based on big clinical data is available. TIMER2, GEPIA2, UALCAN, cBioPortal, String, Metascape, and other web databases were searched in the present study. Generally, MMP7 expression is significantly upregulated in most The Cancer Genome Atlas (TCGA) cancer types compared to the paired normal controls, yet is downregulated in tumor tissues of invasive breast carcinoma (BRCA), kidney chromophobe (KICH), kidney renal clear cell carcinoma (KIRC), liver hepatocellular carcinoma (LIHC), and skin cutaneous melanoma (SKCM). MMP7 protein expression is notably higher in the primary tumor tissues of colon cancer, lung adenocarcinoma (LUAD), and uterine corpus endometrial carcinoma (UCEC) than in normal tissues and is significantly lower in the primary tumor tissues of breast cancer, clear cell renal carcinoma, and ovarian cancer. Furthermore, MMP7 expression is strongly associated with pathological stages, clinical outcomes, tumor mutational burden (TMB), and microsatellite instability (TSI). Gene amplification was detected in most TCGA cancer types. In addition, the missense mutation is the primary type of MMP7 genetic alteration in tumors. Significant positive correlations between MMP7 expression and cancer-associated fibroblasts (CAFs) have been demonstrated in most TCGA cancers. MMP7 expression was also found to be positively correlated with infiltration of dendritic cells and macrophages in some specific tumor types. Functional enrichment analysis by the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and gene ontology (GO) methods revealed that RNA processing and DNA damage checkpoints might reveal the pathogenetic mechanisms of MMP7. This pan-cancer analysis provides a clear panorama for the tumorigenic roles of MMP7 across different cancer types. Moreover, MMP7 could be a potential drug therapeutic target in such cancers.

13.
Free Radic Biol Med ; 193(Pt 1): 330-341, 2022 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-36279972

RESUMO

BACKGROUND: Diabetes cardiac fibrosis is associated with altered DNA methylation of fibrogenic genes; however, the underlying mechanisms remain unclear. OBJECTIVES: In this study, we investigate the critical role of DNA methylation aberration-associated suppression of MTHFR in diabetes cardiac fibrosis, and the protective effects of folate on diabetes cardiac fibrosis, using cultured cells, animal models, and clinical samples. METHODS AND RESULTS: Herein, we report that DNA methylation repression of MTHFR, critically involved in diabetes cardiac fibrosis, mediates the significant protective effects of folate in a mouse model of diabetes cardiac fibrosis induced by STZ. Heart MTHFR expression was markedly suppressed in diabetes cardiac fibrosis patients and mice, accompanied by increased DNMT3A and MTHFR promoter methylation. Knockdown of DNMT3A demethylated MTHFR promoter, recovered the MTHFR loss, and alleviated the diabetes cardiac fibrosis pathology and cardiac fibroblasts pyroptosis. Mechanistically, DNMT3A epigenetically repressed MTHFR expression via methylation of the promoter. Interestingly, folate supplementation can rescue the effect of MTHFR loss in diabetes cardiac fibrosis, suggesting that inactivation of MTHFR through epigenetics is a critical mediator of diabetes cardiac fibrosis. CONCLUSIONS: The current study identifies that MTHFR repression due to aberrant DNMT3A elevation and subsequent MTHFR promoter hypermethylation is likely an important epigenetic feature of diabetes cardiac fibrosis, and folate supplementation protects against diabetes cardiac fibrosis.


Assuntos
Metilação de DNA , Diabetes Mellitus , Camundongos , Animais , Epigênese Genética , Fibrose , Ácido Fólico , Diabetes Mellitus/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética
14.
Int J Biol Macromol ; 223(Pt A): 899-915, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36370857

RESUMO

Dysregulated glycolysis has been noted in several pathological processes characterized by supporting cell proliferation. Nonetheless, the role of glycolysis reprogramming is not well appreciated in cardiac fibrosis which is accompanied by increased fibroblasts proliferation. In this study, we investigated the cause and consequence of glycolysis reprogramming in cardiac fibrosis, using clinical samples, animal models, and cultured cells. Herein, we report that methyltransferase-like 3 (METTL3) facilitates glycolysis and cardiac fibroblasts proliferation, leading to cardiac fibrosis. The augmentation of glycolysis, an essential event during cardiac fibroblasts proliferation, is dependent on an increased expression of METTL3. A knockdown of METTL3 suppressed glycolysis, and inhibited cardiac fibroblast proliferation and cardiac fibrosis. Mechanistically, METTL3 epigenetically repressed androgen receptor (AR) expression in an m6A-YTHDF2- dependent manner, by targeting the specific AR m6A site. AR could interact with the glycolysis marker HIF-1α, and down-regulation of AR activates HIF-1α signaling, resulting in enhanced glycolysis and cardiac fibroblast proliferation. In contrast, the overexpression of AR significantly reduced the HIF-1α axis, decreased expression of glycolytic enzymes HK3, inhibited glycolysis, and repressed cardiac fibroblasts proliferation. Notably, increased METTL3 and YTHDF2 levels, decreased AR expression, increased HIF-1α and Postn expression and augmented glycolysis, and increased cardiac fibrosis were detected in human atrial fibrillation heart tissues. Our results found a novel mechanism by which METTL3-catalyzed m6A modification in cardiac fibrosis, wherein it facilitated glycolysis and cardiac fibroblasts proliferation by increasing AR methylation in an m6A-YTHDF2- dependent manner and provided new insights strategies to intervene cardiac fibrosis.


Assuntos
Fibroblastos , Glicólise , Animais , Humanos , Metilação , Fibrose , Fibroblastos/metabolismo , Proliferação de Células/genética , Metiltransferases/genética , Metiltransferases/metabolismo
15.
Nanomaterials (Basel) ; 11(9)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34578726

RESUMO

Asymmetric optical transmission plays a key role in many optical systems. In this work, we propose and numerically demonstrate a dielectric-metal metasurface that can achieve high-performance asymmetric transmission for linearly polarized light in the near-infrared region. Most notably, it supports a forward transmittance peak (with a transmittance of 0.70) and a backward transmittance dip (with a transmittance of 0.07) at the same wavelength of 922 nm, which significantly enhances operation bandwidth and the contrast ratio between forward and backward transmittances. Mechanism analyses reveal that the forward transmittance peak is caused by the unidirectional excitation of surface plasmon polaritons and the first Kerker condition, whereas the backward transmittance dip is due to reflection from the metal film and a strong toroidal dipole response. Our work provides an alternative and simple way to obtain high-performance asymmetric transmission devices.

16.
Cardiovasc Toxicol ; 21(12): 984-999, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34424481

RESUMO

Novel insights into epigenetic control of cardiac fibrosis are now emerging. Cardiac fibroblasts (CFs) activation into myofibroblasts and the production of extracellular matrix (ECM) is the key to cardiac fibrosis development, but the specific mechanism is not fully understood. In the present study, we found that DNMT1 hypermethylation reduces the expression of microRNA-152-3p (miR-152-3p) and promotes Wnt1/ß-catenin signaling pathway leading to CFs proliferation and activation. Cardiac fibrosis was produced by ISO, and the ISO was carried out according to the method described. CFs were harvested and cultured from SD neonatal rats and stimulated with TGF-ß1. Importantly, DNMT1 resulted in the inhibition of miR-152-3p in activated CFs and both DNMT1 and miR-152-3p altered Wnt/ß-catenin downstream protein levels. Over expression of DNMT1 and miR-152-3p inhibitors promotes proliferation of activating CFs. In addition, decreased methylation levels and over expression of miR-152-3p inhibited CFs proliferation. We determined that DNMT1 can methylate to miR-152-3p and demonstrated that expression of miR-152-3p inhibits CFs proliferation by inhibiting the Wnt1/ß-catenin pathway. Our results stand out together DNMT1 methylation regulates miR-152-3p to slow the progression of cardiac fibrosis by inhibiting the Wnt1/ß-catenin pathway.


Assuntos
Cardiomiopatias/enzimologia , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Fibroblastos/enzimologia , MicroRNAs/metabolismo , Miocárdio/enzimologia , Animais , Cardiomiopatias/genética , Cardiomiopatias/patologia , Proliferação de Células , Células Cultivadas , DNA (Citosina-5-)-Metiltransferase 1/genética , Metilação de DNA , Modelos Animais de Doenças , Regulação para Baixo , Epigênese Genética , Fibroblastos/patologia , Fibrose , Masculino , MicroRNAs/genética , Miocárdio/patologia , Fenótipo , Ratos Sprague-Dawley , Via de Sinalização Wnt
17.
Toxicology ; 410: 182-192, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30114436

RESUMO

Modulation of epigenetic marks has promised efficacy for treating fibrosis. Cardiac fibroblast is the primary source of activated myofibroblasts that produce extracellular matrix (ECM) in cardiac fibrosis, but the mechanisms underlying this process are incompletely understood. Here we show that microRNA-369-5p (miR-369-5p) through DNMT3A hypermethylation and suppression of the Patched1 pathway leads to fibroblast proliferation in cardiac fibrosis. Forty adult male Sprague-Dawley (SD) rats were randomly divided into two groups (sham and AAC group), cardiac fibrosis was produced by abdominal aortic constriction, and the operation of abdominal aortic constriction was carried out according to the method described. Cardiac fibroblasts (CFs) were harvested from SD neonate rats and cultured. Importantly, miR-369-5p bind directly to DNMT3A with high affinity. MiR-369-5p leads to inhibition of DNMT3A enzyme activity. Exogenous miR-369-5p in cells induces aberrant DNA methylation of the Patched1, resulting in hypermethylation of low to moderately methylated regions. Moreover, Overexpression of miR-369-5p in cardiac fibroblast cells inhibits proliferation. We identify DNMT3A as miR-369-5p target genes and demonstrate that inhibition of miR-369-5p expression augments cell proliferation by activating DNMT3A and suppression of the Patched1 pathway. Together, our results highlight miR-369-5p mediated DNMT3A epigenetic silencing of Patched1 as a mechanism of fibroblast proliferation in cardiac fibrosis.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Fibrose Endomiocárdica/genética , Epigênese Genética/efeitos dos fármacos , MicroRNAs/genética , Receptor Patched-1/genética , Transdução de Sinais/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Constrição Patológica , Metilação de DNA/genética , DNA Metiltransferase 3A , Ecocardiografia Doppler , Fibrose Endomiocárdica/diagnóstico por imagem , Epigênese Genética/genética , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/genética , Fibroblastos/patologia , Masculino , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Sprague-Dawley
18.
Int J Clin Exp Med ; 8(4): 5004-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26131073

RESUMO

OBJECTIVE: This study aims to explore the analgesic effects of melatonin on post-herpetic neuralgia and its possible mechanism. METHODS: A total of 48 PHN Wistar rats were divided into 4 groups randomly: Normal, PHN, PHN+MT and naloxone, 4P-PDOT or L-arginine+120 mg/kg MT (C). Heat pain latency was determined after MT injection for 20 min, 40 min, 80 min and 120 min respectively. The expression levels of δ receptor and MT2 receptor in different tissues of rats were detected by RT-PCR method. NO content was determined. RESULTS: Heat pain latency in PHN rats were lower than that of control group (P<0.05), MT could increase the heat pain latency with dose-dependent, while naloxone, 4P-PDOT and L-arginine could reverse the analgesic effect of MT (P<0.05). The expression levels of δ receptor and MT2 receptor in spinal cord, hypothalamus and hippocampus in PHN+MT (120 mg/kg, i. p.) group were significantly higher than that of PHN group (P<0.05). The NO levels in the brain and spinal cord tissues in PHN group were higher than that of PHN+MT (120 mg/kg) group (P<0.05). CONCLUSIONS: MT had significant analgesic effects in the treatment of PHN, and its mechanism was closely related with δopioid receptor, NO and MT2 receptor.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa