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Background: It had been shown that selective cardiac vagal activation holds great potential for heart regeneration. Optogenetics has clinical translation potential as a novel means of modulating targeted neurons. This study aimed to investigate whether cardiac vagal activation via optogenetics could improve heart regenerative repair after myocardial infarction (MI) and to identify the underlying mechanism. Methods: We used an adeno-associated virus (AAV) as the vector to deliver ChR2, a light-sensitive protein, to the left nodose ganglion (LNG). To assess the effects of the cardiac vagus nerve on cardiomyocyte (CM) proliferation and myocardial regeneration in vivo, the light-emitting diode illumination (470 nm) was applied for optogenetic stimulation to perform the gain-of-function experiment and the vagotomy was used as a loss-of-function assay. Finally, sequencing data and molecular biology experiments were analyzed to determine the possible mechanisms by which the cardiac vagus nerve affects myocardial regenerative repair after MI. Results: Absence of cardiac surface vagus nerve after MI was more common in adult hearts with low proliferative capacity, causing a poor prognosis. Gain- and loss-of-function experiments further demonstrated that optogenetic stimulation of the cardiac vagus nerve positively regulated cardiomyocyte (CM) proliferation and myocardial regeneration in vivo. More importantly, optogenetic stimulation attenuated ventricular remodeling and improved cardiac function after MI. Further analysis of sequencing results and flow cytometry revealed that cardiac vagal stimulation activated the IL-10/STAT3 pathway and promoted the polarization of cardiac macrophages to the M2 type, resulting in beneficial cardiac regenerative repair after MI. Conclusions: Targeting the cardiac vagus nerve by optogenetic stimulation induced macrophage M2 polarization by activating the IL-10/STAT3 signaling pathway, which obviously optimized the regenerative microenvironment and then improved cardiac function after MI.
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Interleucina-10 , Infarto do Miocárdio , Adulto , Humanos , Interleucina-10/genética , Optogenética , Infarto do Miocárdio/terapia , Nervo Vago , Miócitos CardíacosRESUMO
Trifluoromethyl cationic carbyne (CF3 C+ :) possessing dual carbene-carbocation behavior emulated as trifluoromethyl metal-carbynoid (CF3 C+ =M) has not been explored yet, and its reaction characteristics are unknown. Herein, a novel α-diazotrifluoroethyl sulfonium salt was prepared and used in Rh-catalyzed three-component [2+1+2] cycloadditions for the first time with commercially available N-fused heteroarenes and nitriles, yielding a series of imidazo[1,5-a] N-heterocycles that are of interest in medicinal chemistry, in which the insertion of trifluoromethyl Rh-carbynoid (CF3 C+ =Rh) into C=N bonds of N-fused heteroarenes was involved. This strategy demonstrates synthetic applications in late-stage modification of pharmaceuticals, construction of CD3 -containing N-heterocycles, gram-scale experiments, and synthesis of phosphodiesterase 10A inhibitor analog. These highly valuable and modifiable imidazo[1,5-a] N-heterocycles exhibit good antitumor activity in vitro, thus demonstrating their potential applications in medicinal chemistry.
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Rye (Secale cereale), a valuable relative of wheat, contains abundant powdery mildew resistance (Pm) genes. Using physical mapping, transcriptome sequencing, barley stripe mosaic virus-induced gene silencing, ethyl methane sulfonate mutagenesis, and stable transformation, we isolated and validated two coiled-coil, nucleotide-binding site and leucine-rich repeat (CC-NBS-LRR) alleles, PmTR1 and PmTR3, located on rye chromosome 6RS from different triticale lines. PmTR1 confers age-related resistance starting from the three-leaf stage, whereas its allele, PmTR3, confers typical all-stage resistance, which may be associated with their differential gene expression patterns. Overexpression in Nicotiana benthamiana showed that the CC, CC-NBS, and CC-LRR fragments of PMTR1 induce cell death, whereas in PMTR3 the CC and full-length fragments perform this function. Luciferase complementation imaging and pull-down assays revealed distinct interaction activities between the CC and NBS fragments. Our study elucidates two novel rye-derived Pm genes and their derivative germplasm resources and provides novel insights into the mechanism of age-related resistance, which can aid the improvement of resistance against wheat powdery mildew.
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Ascomicetos , Secale , Secale/genética , Resistência à Doença/genética , Triticum/genética , Proteínas de Repetições Ricas em Leucina , Ascomicetos/fisiologia , Nucleotídeos , Cromossomos de Plantas/genética , Sítios de Ligação , Doenças das Plantas/genéticaRESUMO
A highly active catalyst for the oxygen evolution reaction (OER) is critical to achieve high efficiency in hydrogen generation from water splitting. Direct conversion of nickel foam (NF) into nickel-based catalysts has attracted intensive interest due to the tight interaction of the catalysts to the substrate surface. However, the catalytic performances are still far below expectation because of the problems of low catalyst amount, thin catalyst layer, and small active area caused by the limitations of the synthesis method. Herein, we develop a Fe3+ -induced synthesis strategy to transform the NF surface into a thicker catalyst layer. In addition to the excellent conductivity and high stability, the as-prepared FeMo-Ni2 P2 O7 /NF catalysts expose more active sites and facilitate mass transfer due to their thicker catalyst layer and highly dense coral-like micro-nano structure. Furthermore, the Mo, Fe co-modulation optimizes the adsorption free energies of the OER intermediates, boosting catalytic activities. Its catalytic activity is among the highest, and it exhibits a small Tafel slope of 34.71â mV dec-1 and a low overpotential of 161â mV for delivering a current density of 100â mA cm-2 compared to reported Ni-based catalysts. The present strategy can be further used in the design of other catalysts for energy storage and conversion.
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Background: Hepatocellular carcinoma (HCC) is the most common and deadly type of liver cancer. Autophagy is the process of transporting damaged or aging cellular components into lysosomes for digestion and degradation. Accumulating evidence implies that autophagy is a key factor in tumor progression. The aim of this study was to determine a panel of novel autophagy-related prognostic markers for liver cancer. Methods: We conducted a comprehensive analysis of autophagy-related gene (ARG) expression profiles and corresponding clinical information based on The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) databases. The univariate Cox proportional regression model was used to screen candidate autophagy-related prognostic genes. In addition, a multivariate Cox proportional regression model was used to identify five key prognostic autophagy-related genes (ATIC, BAX, BIRC5, CAPNS1, and FKBP1A), which were used to construct a prognostic signature. Real-time qPCR analysis was used to evaluate the expression levels of ARGs in 20 surgically resected HCC samples and matched tumor-adjacent normal tissue samples. In addition, the effect of FKBP1A on autophagy and tumor progression was determined by performing in vitro and in vivo experiments. Results: Based on the prognostic signature, patients with liver cancer were significantly divided into high-risk and low-risk groups in terms of overall survival (OS). A subsequent multivariate Cox regression analysis indicated that the prognostic signature remained an independent prognostic factor for OS. The prognostic signature possessing a better area under the curve (AUC) displayed better performance in predicting the survival of patients with HCC than other clinical parameters. Furthermore, FKBP1A was overexpressed in HCC tissues, and knockdown of FKBP1A impaired cell proliferation, migration, and invasion through the PI3K/AKT/mTOR signaling pathway. Conclusion: This study provides a prospective biomarker for monitoring outcomes of patients with HCC.
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The annotation of brain lesion images is a key step in clinical diagnosis and treatment of a wide spectrum of brain diseases. In recent years, segmentation methods based on deep learning have gained unprecedented popularity, leveraging a large amount of data with high-quality voxel-level annotations. However, due to the limited time clinicians can provide for the cumbersome task of manual image segmentation, semi-supervised medical image segmentation methods present an alternative solution as they require only a few labeled samples for training. In this paper, we propose a novel semi-supervised segmentation framework that combines improved mean teacher and adversarial network. Specifically, our framework consists of (i) a student model and a teacher model for segmenting the target and generating the signed distance maps of object surfaces, and (ii) a discriminator network for extracting hierarchical features and distinguishing the signed distance maps of labeled and unlabeled data. Besides, based on two different adversarial learning processes, a multi-scale feature consistency loss derived from the student and teacher models is proposed, and a shape-aware embedding scheme is integrated into our framework. We evaluated the proposed method on the public brain lesion datasets from ISBI 2015, ISLES 2015, and BRATS 2018 for the multiple sclerosis lesion, ischemic stroke lesion, and brain tumor segmentation respectively. Experiments demonstrate that our method can effectively leverage unlabeled data while outperforming the supervised baseline and other state-of-the-art semi-supervised methods trained with the same labeled data. The proposed framework is suitable for joint training of limited labeled data and additional unlabeled data, which is expected to reduce the effort of obtaining annotated images.
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Neoplasias Encefálicas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Aprendizado Profundo , Esclerose Múltipla/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Conjuntos de Dados como Assunto , Humanos , Imageamento por Ressonância Magnética , Projetos de Pesquisa , EstudantesRESUMO
Immunity plays an important role in tumor development. In this study, we aimed to investigate molecular classification and its prognostic value in hepatocellular carcinoma (HCC) based on immune signature. Gene set enrichment analysis (GSEA) was used to calculate scores of immune pathways for HCC and hierarchical clustering in two databases (The Cancer Genome Atlas [TCGA], Liver Cancer-RIKEN, JP [LIRI_JP]). The scores of the immune microenvironment and the proportions of 22 immune cells were also calculated. Single-sample GSEA (ssGSEA) was used to screen survival prognosis-related immune pathways and calculate the hazard radio of differentially expressed immune-related genes (IRGs), which were validated in clinical samples and multiple datasets. Based on the immune characteristics, we identified three HCC subtypes, namely immunity high (Immunity_H), immunity medium (Immunity_M), and immunity low (Immunity_L), and confirmed that the classification was reliable and predictable. Immunity_H with a higher immune and stromal score indicated better survival rate. Cox regression analysis showed that IL18RAP and IL7R were the protective genes. Immune risk score was the independent risk factor of overall survival in HCC patients. These results indicated that immunogenomic classification could distinguish HCC patients with different immune status, which could impact the prognosis of the patients with HCC.
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Transcriptome analysis is used to study gene expression in human tissues. It can promote the discovery of new therapeutic targets for related diseases by characterizing the endocrine function of pancreatic physiology and pathology, as well as the gene expression of pancreatic tumors. Compared to whole-tissue RNA sequencing, single-cell RNA sequencing (scRNA-seq) can detect transcriptional activity within a single cell. The scRNA-seq had an invaluable contribution to discovering previously unknown cell subtypes in normal and diseased pancreases, studying the functional role of rare islet cells, and studying various types of cells in diabetes as well as cancer. Here, we review the recent in vitro and in vivo advances in understanding the pancreatic physiology and pathology associated with single-cell sequencing technology, which may provide new insights into treatment strategy optimization for diabetes and pancreatic cancer.
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Cantharidin (CTD), a natural Chinese medicine constituent extracted from mylabris, is a potent drug against hepatocellular carcinoma. However, the clinical application of CTD was limited because of its toxicity and low solubility. In this work, a novel CTD-loaded liposome modified with 3-succinyl-30-stearyl glycyrrhetinic acid (18-GA-Suc-CTD-Lip) was prepared to enhance liver-targeting efficiency and antitumor activity. 18-GA-Suc-CTD-Lip and CTD-Lip were successfully prepared by film dispersion method and totally characterized. The antitumor effects in vitro were evaluated by cell proliferation inhibition assay, transwell assay, cell cycle analysis, and an apoptosis test. Pharmacokinetic and biodistribution were all investigated to precisely reveal liver-targeting efficiency of 18-GA-Suc-CTD-Lip in vivo. The IC50 values of 18-GA-Suc-CTD-Lip in HepG2 (3.417 ± 0.165 nmol/L) and Huh-7 (4.478 ± 0.409 nmol/L) cells were much lower than that of CTD-Lip, indicating that antitumor effects of 18-GA-Suc-CTD-Lip were remarkable because of the modification of 18-GA-Suc. The maximum concentration in the liver of 18-GA-Suc-CTD-Lip (1.72 ± 0.14 µg/g) was more than twice CTD-Lip (0.75 ± 0.08 µg/g) at 30 min, illustrating that 18-GA-Suc-CTD-Lip possesses excellent liver-targeting efficiency. Conclusively, 18-GA-Suc-CTD-Lip could be a potential liver-targeting antitumor drug for hepatocellular carcinoma.
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Lipossomos , Neoplasias Hepáticas , Cantaridina , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Distribuição TecidualRESUMO
Excessive neuroinflammation aggravates neurological damage after spinal cord injury (SCI). Controlling neuroinflammation might favor neuroregeneration and tissue repair. Dexmedetomidine is reported to inhibit post-SCI neuroinflammation in previous research. In the current study, to determine the mechanisms by which dexmedetomidine inhibits neuroinflammation, we tested the effect of dexmedetomidine hydrochloride on microglia in vitro and in a rat SCI model. We found that dexmedetomidine hydrochloride up-regulated programmed cell death protein 1 (PD-1), an immunoregulatory molecule, in activated microglia but not in resting microglia. In the presence of programmed death-ligand 1 (PD-L1), this enhanced PD-1 expression downregulated pro-inflammatory cytokine expression and upregulated anti-inflammatory cytokine expression in activated microglia. PD-L1/PD-1 engagement also induced microglia polarization toward the immunoregulatory M2 type. Moreover, dexmedetomidine hydrochloride promoted 5' adenosine monophosphate-activated protein kinase (AMPK) signaling in activated microglia. AMPK signaling was responsible for the above-mentioned changes of cytokine expression and M2 microglia polarization. Consistently, intraperitoneal injection of dexmedetomidine hydrochloride had a similar effect on microglia in the rat SCI model. Taken together, our study disclosed a novel mechanism underlying the anti-neuroinflammatory effect of dexmedetomidine: dexmedetomidine promotes AMPK signaling in activated microglia via upregulation of microglial PD-1 expression, and subsequently drives microglia polarization toward M2 type.
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Anti-Inflamatórios/farmacologia , Dexmedetomidina/farmacologia , Inflamação/patologia , Microglia/metabolismo , Receptor de Morte Celular Programada 1/biossíntese , Traumatismos da Medula Espinal/patologia , Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Animais , Inflamação/metabolismo , Masculino , Microglia/efeitos dos fármacos , Receptor de Morte Celular Programada 1/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Traumatismos da Medula Espinal/metabolismo , Regulação para CimaRESUMO
Calcium sulfate is in routine clinical use as a bone substitute, offering the benefits of biodegradability, biocompatibility and a long history of use in bone repair. The osteoconductive properties of calcium sulfate may be further improved by doping with strontium ions. Nevertheless, the high degradation rate of calcium sulfate may impede bone healing as substantial material degradation may occur before the healing process is complete. The purpose of this study is to develop a novel composite bone substitute composed of chitosan and strontium-doped α-calcium sulfate hemihydrate in the form of microcapsules, which can promote osteogenesis while matching the natural rate of bone healing. The developed microcapsules exhibited controlled degradation that facilitated the sustained release of strontium ions. In vitro testing showed that the microcapsules had minimal cytotoxicity and ability to inhibit bacterial growth. In vivo testing in a mouse model showed the absence of genetic toxicity and low inflammatory potential of the microcapsules. The novel microcapsules developed in this study demonstrated suitable degradation characteristics for bone repair as well as favourable in vitro and in vivo behaviour, and hold promise for use as an alternative bone substitute in orthopaedic surgery.
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Materiais Biocompatíveis/química , Substitutos Ósseos/química , Sulfato de Cálcio/química , Quitosana/química , Estrôncio/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Substitutos Ósseos/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Feminino , Masculino , Camundongos , Músculo Esquelético/patologia , Próteses e Implantes , Ratos , Testes de ToxicidadeRESUMO
TNF-α, one of the most potent pro-inflammatory cytokines, plays a critical role in inhibition of osteoblast differentiation and bone regeneration in persistent inflammatory microenvironment. To explore the mechanism, quantitative proteomics based on iTRAQ and MRM was employed. The results showed 6 proteins involved in BMP-2 induced osteoblast differentiation inhibition by TNF-α: Periostin, Protein S100-A4, ATPase inhibitor, Cytochrome b5, SERCA3, and ELP2. The altered proteins were involved in molecular transport, tissue development, energy metabolism, and inflammation. One specific protein, ELP2 (STAT3-interacting protein 1, StIP1) up-regulated in the inhibition of osteoblast differentiation by TNF-α was verified to play a critical role in STAT3 pathway. Overexpression or knockdown of ELP2 in C2C12 and MC3T3-E1 cells affected osteoblast differentiation inhibition induced by TNF-α. These results highlight the function of ELP2 in inflammatory microenvironment, ELP2 up-regulation and STAT3 pathway activation may down-regulate BMPR2, then BMP-2 was blocked and osteoblast differentiation inhibited. The protein-expression profile revealed here should offer at least partly new clues to understand the mechanism of osteoblast differentiation inhibition by inflammation. BIOLOGICAL SIGNIFICANCE: Persistent inflammation is always associated with osteogenesis and affects this balance to reduce bone mass including traumatic open bone fracture, rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), but the cellular mechanisms are not fully elucidated. Tumor necrosis factor-α (TNF-α) is one of the most potent pro-inflammatory cytokines and is known to be a catabolic factor in these inflammatory reaction of diseases. We show for the first time using proteomics methods that in inflammatory microenvironment, osteoblast differentiation will be inhibited by TNF-α induced ELP2 up-regulation and STAT3 pathway activation. Our results are significant since they point to targeting ELP2 activity as a novel therapeutic option to limit the inhibition of osteoblast differentiation by inflammatory microenvironment.
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Diferenciação Celular/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Osteoblastos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Sequência de Aminoácidos , Animais , Células Cultivadas , Microambiente Celular , Regulação para Baixo/efeitos dos fármacos , Inflamação/metabolismo , Inflamação/patologia , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Dados de Sequência Molecular , Osteoblastos/fisiologia , Mapeamento de Interação de Proteínas , Proteômica/métodosRESUMO
BACKGROUND: The aim of this study was to determine the effectiveness and short-term outcomes of endovenous laser therapy (EVLT) combined with pinhole high ligation (PHL) in the treatment of great saphenous varicose veins. METHODS: From February 2011 to May 2012, 200 patients with great saphenous varicose veins were treated using combined EVLT and PHL. Sixty-eight of them had concurrent TriVex suction. There were 118 men and 82 women with a median age of 61 (range 28-82) years. All patients had more than one of the following presentations, including lower extremity heaviness, pain, edema, varicose vein, skin changes, or ulceration. Based on the CEAP clinical classification, 20 patients had C2, 85 had C3, 48 had C4, 23 had C5, and 24 had C6 chronic venous disease. Ninety patients had VV involving the left lower extremity, 56 involving the right lower extremity, and 54 involving the bilateral lower extremities. Duplex ultrasound (US) was performed for all the 200 patients, and showed great saphenous valve dysfunction and reflux in 148 patients. Fifty-two of the 200 patients had concurrent mild femoral vein reflux. Deep venous thrombosis (DVT) was ruled out in all the patients. RESULTS: Technical success rate of PHL and laser ablation was 100%. Median follow-up was 9 months, ranging from 3 to 20 months. Symptoms were resolved or significantly improved in all patients after surgery. The ulcers healed in 23 of the 24 patients (96%) within 3 months. Ten patients developed subcutaneous hematoma, and 8 had slightly worsening edema. Ten patients with complications of numbness due to saphenous nerve burning injury were treated with mecobalamin, and the numbness sensation improved within 1 month and disappeared within 3 months. Nine patients sustained saphenous vein thrombophlebitis postoperatively and were treated with ibuprofen and a heating pad. There was no recanalization of the great saphenous vein, deep venous thrombosis (DVT), or deaths in this group of patients. CONCLUSIONS: Combined EVLT and PHL are less invasive and are effective in the treatment of symptomatic great saphenous varicose veins. PHL prevents DVT, and significantly decreases recanalization of the great saphenous vein after endovenous laser ablation. Short-term outcomes have been satisfactory, but long-term follow-up is needed.
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Procedimentos Endovasculares/métodos , Terapia a Laser , Veia Safena/cirurgia , Varizes/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Terapia a Laser/efeitos adversos , Ligadura , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Veia Safena/diagnóstico por imagem , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia Doppler Dupla , Varizes/diagnóstico , CicatrizaçãoRESUMO
BACKGROUND AND PURPOSE: Remote ischemic postconditoning, a phenomenon in which brief ischemic stimuli of 1 organ protect another organ against an ischemic insult, has been demonstrated to protect the myocardium and adult brain in animal models. However, mediators of the protection and underlying mechanisms remain to be elucidated. In the present study, we tested the hypothesis that remote limb ischemic postconditioning applied immediately after hypoxia provides neuroprotection in a rat model of neonatal hypoxia-ischemia (HI) by mechanisms involving activation of the opioid receptor/phosphatidylinositol-3-kinase/Akt signaling pathway. METHODS: HI was induced in postnatal Day 10 rat pups by unilateral carotid ligation and 2 hours of hypoxia. Limb ischemic postconditioning was induced by 4 conditioning cycles of 10 minutes of ischemia and reperfusion on both hind limbs immediately after HI. The opioid antagonist naloxone, phosphatidylinositol-3-kinase inhibitor wortmannin, or opioid agonist morphine was administered to determine underlying mechanisms. Infarct volume, brain atrophy, and neurological outcomes after HI were evaluated. Expression of phosphorylated Akt, Bax, and phosphorylated ERK1/2 was determined by Western blotting. RESULTS: Limb ischemic postconditioning significantly reduced infarct volume at 48 hours and improved functional outcomes at 4 weeks after HI. Naloxone and wortmannin abrogated the postconditioning-mediated infarct-limiting effect. Morphine given immediately after hypoxia also decreased infarct volume. Furthermore, limb ischemic postconditioning recovered Akt activity and decreased Bax expression, whereas no differences in phosphorylated ERK1/2expression were observed. CONCLUSIONS: Limb ischemic postconditioning protects against neonatal HI brain injury in rats by activating the opioid receptor/phosphatidylinositol-3-kinase/Akt signaling pathway.
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Membro Posterior/irrigação sanguínea , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/prevenção & controle , Pós-Condicionamento Isquêmico/métodos , Proteínas Proto-Oncogênicas c-akt/fisiologia , Receptores Opioides/fisiologia , Transdução de Sinais/fisiologia , Fatores Etários , Animais , Animais Recém-Nascidos , Isquemia/metabolismo , Isquemia/prevenção & controle , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: To study the effects of combination of angiopoietin-1 (ANG-1) and vascular endothelial growth factor165 (VEGF165) gene transfer mediated by recombinant adeno-associated viral vector on the neovascularization in chronic ischemic porcine myocardium. METHODS: An ameroid constrictor was implanted around the left circumflex coronary artery (LCX) via endoscopy. Six weeks later, coronary angiography revealed that the myocardial ischemia was established by gradual occlusion of the left circumflex coronary artery (LCX). Sixteen swine with the total occlusion or partial stenosis (> 85 %) of the LCX were divided into 4 groups (4 in each group): group I, group II and group IV (control) received direct myocardium injection of rAAV2 VEGF165, rAAV2 ANG-1 or PBS alone, respectively; group III received rAAV2 VEGF165 and rAAV2 ANG-1. Selective coronary angiography and ultrasonography were performed perioperatively to evaluate the cardiac function and the formation of collateral circulation. The expression of VEGF165 and ANG-1 proteins were assessed using ELISA or Western blot. The degree of angiogenesis was assessed by use of immunohistochemical analysis. RESULT: Angiography showed that the occlusion of all LCX was completed or exceeded 95% 6 weeks after ameroid constrictor implantation, indicating the successful establishment of animal model. The expression levels of VEGF165 in group I and III and ANG-1 in groups II and III began to increase at d7 after transfection and reached the peak at d14; then decreased gradually to the normal level after 3 months. The expression levels of VEGF165 in group II and group IV or that of ANG-1 protein in group I and group IV had no markedly changes at different time after transfection. There were significant increase in capillary density and arteriole density and more side branch vessels formed in group III compared with other groups. Echocardiographic measurements showed that the left ventricular systolic function of animals in groups I, II and III increased significantly after gene transfection, especially in group III; but there was no changes in group IV. CONCLUSION: Myocardial perfusion and the left ventricular systolic function are improved after rAAV2 VEGF165 or rAAV2 ANG-1 transfection, which is associated with the angiogenesis in porcine model of chronic myocardial ischemia.
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Angiopoietina-1/genética , Isquemia Miocárdica/fisiopatologia , Neovascularização Fisiológica , Fator A de Crescimento do Endotélio Vascular/genética , Adenoviridae/genética , Animais , Circulação Colateral , Vasos Coronários/fisiopatologia , Modelos Animais de Doenças , Terapia Genética , Vetores Genéticos , Masculino , Isquemia Miocárdica/terapia , Suínos , Porco Miniatura , TransfecçãoRESUMO
BACKGROUND AND PURPOSE: Isoflurane, administered before or during cerebral ischemia, has been shown to exhibit neuroprotection in animal models of ischemic stroke. However, the underlying mechanism remains to be elucidated. In the present study, we determined whether isoflurane posttreatment provides neuroprotection after neonatal hypoxia-ischemia (HI) in rats and evaluated the role of the sphingosine-1-phosphate/phosphatidylinositol-3-kinase/Akt pathway in this volatile anesthetic-mediated neuroprotection. METHODS: HI was induced in postnatal day 10 (P10) rat pups by unilateral carotid ligation and 2 hours of hypoxia. For treatment, 2% isoflurane was administered immediately after HI for 1 hour. As pharmacological interventions, the sphingosine-1-phosphate antagonist VPC23019, phosphatidylinositol-3-kinase inhibitor wortmannin, or opioid antagonist naloxone was administered before HI. Isoflurane posttreatment was evaluated for effects on infarct volume at 48 hours after HI and brain atrophy and neurological outcomes at 4 weeks after HI. The expression of phosphorylated Akt and cleaved caspase-3 was determined by Western blotting and immunofluorescence analysis. RESULTS: Isoflurane posttreatment significantly reduced infarct volume at 48 hours after HI. VPC23019 or wortmannin abrogated the neuroprotective effect of isoflurane, whereas naloxone did not inhibit the isoflurane-induced neuroprotection. Isoflurane posttreatment significantly preserved phosphorylated Akt expression and decreased cleaved caspase-3 levels. These effects were reversed by VPC23019 and wortmannin, respectively. Isoflurane also confers long-term neuroprotective effects against brain atrophy and neurological deficits at 4 weeks after HI. CONCLUSIONS: Isoflurane posttreatment provides lasting neuroprotection against hypoxic-ischemic brain injury in neonatal rats. Activation of the sphingosine-1-phosphate/phosphatidylinositol-3-kinase/Akt pathway may play a key role in isoflurane posttreatment-induced neuroprotection.
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Hipóxia-Isquemia Encefálica/metabolismo , Isoflurano/administração & dosagem , Lisofosfolipídeos/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Transdução de Sinais/fisiologia , Esfingosina/análogos & derivados , Animais , Animais Recém-Nascidos , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/enzimologia , Fármacos Neuroprotetores/administração & dosagem , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Esfingosina/fisiologia , Fatores de Tempo , Resultado do TratamentoRESUMO
Studies on the peroxidation of polyunsaturated fatty acid from yolk lipoprotein induced by iron was curried out. A comparison of the experimental conditions for the model system of peroxidation was made. The system was successfully applied to determine the activity of the anti-oxidative activity of some effective ingredients of Chinese traditional medicine.