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1.
Microb Pathog ; 184: 106341, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37704061

RESUMO

Gosling gout has posed a serious threat to the development of the China's goose industry since the outbreak in mainland China in 2016; goose astrovirus (GAstV) was identified as the culprit pathogen. Two genotypes of this virus have been identified: GAstV-1 and GAstV-2, of which GAstV-2 is the main epidemic strain. Our current understanding of the pathogenic mechanisms of GAstV-2 remains limited. To assess pathogenicity, 1-day-old goslings were inoculated with the GAstV-2 YC20 strain via the subcutaneous, intranasal, and oral infection routes. All the goslings showed typical gout symptoms, with those in the oral infection group exhibiting earlier and more severe clinical symptoms, the highest mortality rate, and greatest weight loss. The blood biochemical indicators, viral loads in cloacal swabs and all representative tissues, and serum antibody titers of all infection groups increased significantly, and no significant differences in these parameters were observed among the three infection groups. Histopathological studies showed that the livers, kidneys, and spleens were the main damaged organs, and the pathological changes in the oral group were more severe than those in the other groups. Further analysis revealed that hepatic sinuses narrowed or became occluded as early as 1 day post-inoculation; urate deposition occurred in the renal tubules at 2 days post-inoculation (dpi), followed by necrosis of renal tubular epithelial cells; and lymphocytic infiltration appeared in the splenic tissue at 5 dpi. These results further our understanding of the pathogenic mechanisms of GAstV-2 and provide a reference for future studies.


Assuntos
Infecções por Astroviridae , Avastrovirus , Gota , Doenças das Aves Domésticas , Animais , Gansos , Infecções por Astroviridae/veterinária , Virulência , Avastrovirus/genética , Gota/veterinária , Filogenia
2.
Cells Tissues Organs ; 212(2): 147-154, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34695819

RESUMO

There is no authoritative characterization of the attributes of the hemolymph node (HLN) since Gibbes' first description in 1884. Early reports showed that HLN are found near the kidney in human and animals with the feature of numerous erythrocytes in sinuses. Subsequent studies mainly focused on anatomy and histology, such as the source, distribution, and quantity of erythrocytes in sinuses. Recent articles mentioned that the emergence of HLN was related to immunity, but there was no strong evidence to support this hypothesis. Therefore, it is still uncertain whether the HLN is an organ of anatomy, histology, or immunology. It has been found that the development of HLN could be elicited in the parathymic area by stimuli such as Escherichia coli, allogeneic breast cancer cells, and renal tissue that were injected/transplanted into the tail of rats in our pilot studies. In this study, the model of the HLN was established by transferring allogeneic renal tissue in the rat. Intrasinusoidal erythrocytes of the node were the component for producing a red macroscopic appearance, while macrophage-erythrocyte-lymphocyte rosettes were the major immunomorphological changes, reflecting the immune activity against the invasion of the allogeneic tissue within the node. Therefore, the HLN is an immunomorphological organ.


Assuntos
Hemolinfa , Linfonodos , Ratos , Humanos , Animais , Linfonodos/patologia , Rim , Transplante Homólogo , Eritrócitos
3.
Respir Res ; 23(1): 100, 2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35459189

RESUMO

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a highly heterogeneous and fatal lung disease. In addition to dense fibrous tissue, abnormal angiogenesis is also an important feature of IPF. Pigment epithelium-derived factor (PEDF) is an angiogenesis inhibitor and a potential anti-fibrous factor. The purpose of this experiment is to observe the effect of PEDF on bleomycin (BLM)-induced pulmonary fibrosis in rats. METHODS: In vivo, pathological examination and detection of related factors were performed on pulmonary fibrosis induced by BLM in rats, and the temporal and spatial distribution of PEDF was investigated. Furthermore, lung gene delivery (PEDF-adeno-associated virus) was performed to investigate the effect of PEDF on pulmonary fibrosis. In vitro, lentiviral vectors were used to construct PEDF over-expression or knock out primary rat lung (PRL) fibroblasts. The effect of PEDF on fibroblast activation under TGF-ß1 stimulation was evaluated, and the activation of TGF-ß1/smad pathway and PPAR-γ expression (in the presence or absence of PPAR-γ inhibitors) were analyzed. RESULTS: In vivo results showed that PEDF expression decreased during the inflammatory phase and increased during the fibrotic phase. PEDF could inhibit the progression of pulmonary fibrosis in rats. In vitro results showed that PEDF could effectively inhibit TGF-ß1-stimulated fibroblast activation and reduce the production of α-SMA and collagen-I. PEDF could inhibit the TGF-ß1/smad pathway by up-regulating the activity of PPAR-γ. CONCLUSIONS: PEDF can act as an anti-fibrotic factor, inhibit fibroblast activation by upregulating PPAR-γ activity and reduce BLM-induced pulmonary fibrosis in rats.


Assuntos
Bleomicina , Fibrose Pulmonar Idiopática , Animais , Bleomicina/toxicidade , Proteínas do Olho , Fibroblastos/metabolismo , Fibrose , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Crescimento Neural , Receptores Ativados por Proliferador de Peroxissomo/efeitos adversos , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Ratos , Serpinas , Fator de Crescimento Transformador beta1/farmacologia
4.
Appl Environ Microbiol ; 87(11)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33741629

RESUMO

Riemerella anatipestifer is an important pathogen of waterfowl, causing septicemic and exudative diseases. In our previous study, we demonstrated that bacterial virulence and secretion proteins of the type IX secretion system (T9SS) mutant strains Yb2ΔgldK and Yb2ΔgldM were significantly reduced, in comparison to those of wild-type strain Yb2. In this study, the T9SS secretion protein AS87_RS00980, which is absent from the secretion proteins of Yb2ΔgldK and Yb2ΔgldM, was investigated by construction of gene mutation and complementation strains. The virulence assessment showed >1,000-fold attenuated virulence and significantly reduced bacterial loads in the blood of ducks infected with Yb2Δ00980, the AS87_RS00980 gene deletion mutant strain. Bacterial virulence was recovered in complementation strain cYb2Δ00980 Further study indicated that the T9SS secretion protein AS87_RS00980 is a metallophosphoesterase (MPPE), which displayed phosphatase activity and was cytomembrane localized. Moreover, the optimal reactive pH and temperature were determined to be 7.0 and 60°C, respectively, and the Km and Vmax were determined to be 3.53 mM and 198.1 U/mg. The rMPPE activity was activated by Zn2+ and Cu2+ but inhibited by Fe3+, Fe2+, and EDTA. There are five conserved sites, namely, N267, H268 H351, H389, and H391, in the metallophosphatase domain. Mutant proteins Y267-rMPPE and Y268-rMPPE retained 29.30% and 19.81% relative activity, respectively, and mutant proteins Y351-rMPPE, Y389-rMPPE, and Y391-rMPPE lost almost all MPPE activity. Taken together, these results indicate that the R. anatipestiferAS87_RS00980 gene encodes an MPPE that is a secretion protein of T9SS that plays an important role in bacterial virulence.IMPORTANCERiemerella anatipestifer T9SS was recently discovered to be associated with bacterial gliding motility and secretion of virulence factors. Several T9SS genes have been identified, but no effector has been reported in R. anatipestifer to date. In this study, we identified the T9SS secretion protein AS87_RS00980 as an MPPE that displays phosphatase activity and is associated with bacterial virulence. The enzymatic activity of the rMPPE was determined, and the Km and Vmax were 3.53 mM and 198.1 U/mg, respectively. Five conserved sites were also identified. The AS87_RS00980 gene deletion mutant strain was attenuated >1,000-fold, indicating that MPPE is an important virulence factor. In summary, we identified that the R. anatipestiferAS87_RS00980 gene encodes an important T9SS effector, MPPE, which plays an important role in bacterial virulence.


Assuntos
Proteínas de Bactérias/genética , Riemerella/genética , Riemerella/patogenicidade , Proteínas de Bactérias/metabolismo , Riemerella/enzimologia , Virulência
5.
Cardiology ; 146(1): 11-18, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33032289

RESUMO

INTRODUCTION: Our previous study indicated that coronary collateral microcirculation reserve (CCMR), native collaterals, transports blood flow to an ischemic area to reduce ischemic tissue injury. This study aimed to observe the changes of CCMR in the hearts of different month-old rats. METHODS: We selected 2-, 8-, 16-, and 24-month-old rats as the research objects to monitor the changes of CCMR in rats with aging. After acute myocardial infarction, lectin-FITC was injected into the femoral vein vessels of rats to mark CCMR vessels in the ischemic area. RESULTS: Results of the lectin-FITC perfusion experiment indicated that the number and collagen IV coverage of CCMR vessels declined with aging. Moreover, data suggested a correlation between endothelial nitric oxide synthase and a decline in the number of CCMR vessels. CONCLUSION: Aging causes CCMR decline in rats.


Assuntos
Circulação Colateral , Infarto do Miocárdio , Envelhecimento , Animais , Vasos Coronários/diagnóstico por imagem , Microcirculação , Ratos
6.
J Cell Mol Med ; 22(11): 5732-5742, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30230261

RESUMO

Both decreased autophagy positive regulator AMP activated protein kinase (AMPK) level and promoted mitophagy are observed in oxygen-glucose deprivation (OGD) cardiomyocytes treated with pigment epithelium-derived factor (PEDF). This contradictory phenomenon and its underlying mechanisms have not been thoroughly elucidated. Our previous study reveals that PEDF increases the protein kinase Cα (PKCα) and phospho-PKCα (p-PKCα) contents to promote mitophagy. Thus, we investigated the association between PKCα and mitophagy. Here we identify an interaction between PKCα and Unc-51-like kinase 1 (ULK1), essential component of mitophagy. Further analyses show this is a direct interaction within a domain of ULK1 that termed the serine/threonine-rich domain (S/T domain). Notably, a deletion mutant ULK1 that lacks the binding domain is defective in mediating PEDF-induced mitophagy. Furthermore, we demonstrate that ULK1 is phosphorylated at Ser317/555/777 and Raptor is also phosphorylated by phospho-PKCα. Phospho-ULK1 (p-ULK1) at these sites are all essential for PEDF-induced mitophagy and reduce the release of mitochondrial ROS and DNA. This study therefore identifies a previously uncharacterized interaction between the ULK1 and PKCα that can replace the AMPK-dependent mitophagy processes.


Assuntos
Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Proteínas do Olho/genética , Isquemia Miocárdica/genética , Fatores de Crescimento Neural/genética , Proteína Quinase C-alfa/genética , Serpinas/genética , Proteínas Quinases Ativadas por AMP/genética , Animais , Autofagia/genética , Ventrículos do Coração/citologia , Ventrículos do Coração/patologia , Humanos , Mitocôndrias/genética , Mitofagia/genética , Isquemia Miocárdica/patologia , Isquemia Miocárdica/prevenção & controle , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fosforilação , Cultura Primária de Células , Ratos , Proteína Regulatória Associada a mTOR/genética
7.
Biochem Biophys Res Commun ; 500(3): 738-743, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29679573

RESUMO

Circular RNA (circRNAs) is a novel class of endogenous non-coding RNAs which is widely involved in carcinogenesis. Archived formalin-fixed paraffin-embedded (FFPE) specimens represent valuable resources for cancer research. Currently there is a lack of systematic analysis on the feasibility of circRNAs expression analysis using FFPE samples. Here, we reported the first comparison study of circRNA expression from paired fresh frozen and FFPE specimens of lung adenocarcinoma. circRNAs expression of paired lung adenocarcinoma and adjacent normal samples, starting from either fresh frozen or FFPE materials, were analyzed via a high-throughput circRNA microarray. Hierarchical clustering was performed on samples. qRT-PCR was used to confirm the differentially expressed circRNAs. The circRNA regulation networks were built by bioinformatics tools for several candidate circRNAs. Our results demonstrated that there was a good correlation in circRNAs expression analysis utilizing fresh frozen or FFPE tissues. Tumors and adjacent normal tissues can be clustered correctly by the differentially expressed circRNAs in fresh frozen or FFPE groups. Furthermore, three differentially expressed circRNAs, hsa_circRNA_100421, hsa_circRNA_104329 and hsa_circRNA_101969 were verified by qRT-PCR assay. Bioinformatics analysis was also applied to predict the circRNA-miRNA-protein coding gene interaction network for each of above circRNAs. To the best of our knowledge, this is the first report demonstrating that the circRNAs microarray analysis, starting from FFPE specimens, is comparable with that based on fresh frozen samples. Therefore FFPE specimen represents a good substitute for fresh frozen tissue, especially when fresh frozen specimen is limited.


Assuntos
Adenocarcinoma/genética , Formaldeído/química , Secções Congeladas , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Inclusão em Parafina , Adenocarcinoma de Pulmão , Idoso , Análise por Conglomerados , Redes Reguladoras de Genes , Humanos , Masculino , Pessoa de Meia-Idade , RNA , RNA Circular , Reprodutibilidade dos Testes
10.
J Med Virol ; 89(5): 782-790, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27671219

RESUMO

Out of a population of 1,098 enteroviruses (EVs)-positive hand, foot, and mouth disease (HFMD) specimens, 352 were screened positive for EV-A71-accounting for 32.1% of all EV-positive specimens. This percentage denotes EV-A71 as the second major serotype of enteroviruse among HFMD suffers in Taizhou. An epidemic outbreak of EV-A71 among HFMD children was found in Taizhou in the second quarter of 2012. Phylogeny analysis based on the VP1 complete sequences leads us to find a sub-clade (designated TZ1-1) of EV-A71 circulating in Taizhou, whose emergence might be correlated with the epidemic outbreak. This correlation was further supported by the followed two analyses (namely skyline plot of population history and birth-death SIR simulation of epidemic history). And more importantly, at a positively selected site of VP1 caspid, a mutation of N31D was found to be a synapomorphy of TZ1-1 and its occurrence might be correlated with the epidemic outbreak. J. Med. Virol. 89:782-790, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Enterovirus Humano A/classificação , Enterovirus Humano A/genética , Genótipo , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/virologia , Criança , Pré-Escolar , China/epidemiologia , Surtos de Doenças , Enterovirus Humano A/isolamento & purificação , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mutação de Sentido Incorreto , Filogenia , Prevalência , Análise de Sequência de DNA , Proteínas Estruturais Virais/genética
11.
Microvasc Res ; 114: 84-91, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28666802

RESUMO

Angiogenesis assays are important tools for studying both the mechanisms of cardiac angiogenesis and the potential development of therapeutic strategies to ischemic heart diseases. Currently, various assays have been used to quantitate cardiac tubule formation, yet no consensus has been reached regarding a suitable assay for evaluating the efficacy of angiogenic stimulants or inhibitors. Most in vivo angiogenesis assays are complex and difficult to interpret, whereas traditional in vitro angiogenesis models measure only one aspect of this process. To bridge the gap between in vivo and in vitro angiogenesis assays, here, we have developed a novel modified cardiac explants matrigel assay. We observed the morphology of vascular sprouts formed in three forms of cardiac angiogenesis assays then used quantitative image analyses to further compare the morphological features of vascular sprouts formed in two cardiac explants angiogenesis assays. Vascular sprouts formed in the fibronectin group were less and short, whereas those formed in the matrigel group were significantly longer, consisting of more area and branch points. Moreover, we found the benefits of this matrigel model by observing the ability of cardiac explants to form vascular sprouts under normoxia or hypoxia condition in the presence of angiogenic stimulant and inhibitor, VEGF and PEDF. In summary, the above analyses revealed that the morphology of vascular sprouts formed in this model appears more representative of myocardial capillary formation in vivo, and this accessible, reliable angiogenic assay is a more physiologically relevant assay which allows further assessment of pharmacologic compounds on cardiac angiogenesis.


Assuntos
Vasos Coronários/fisiologia , Neovascularização Fisiológica , Indutores da Angiogênese/farmacologia , Inibidores da Angiogênese/farmacologia , Animais , Animais Recém-Nascidos , Hipóxia Celular , Microambiente Celular , Colágeno/metabolismo , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/metabolismo , Combinação de Medicamentos , Fibronectinas/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Laminina/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Proteoglicanas/metabolismo , Ratos Sprague-Dawley , Fatores de Tempo , Técnicas de Cultura de Tecidos
12.
Apoptosis ; 21(1): 60-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26519036

RESUMO

Pigment epithelial-derived factor (PEDF) is a potent anti-angiogenic factor whose effects are partially mediated through the induction of endothelial cell apoptosis. However, the underlying mechanism for PEDF and the functional PEDF peptides 34-mer and 44-mer to inhibit angiogenesis in the heart has not been fully established. In the present study, by constructing adult Sprague-Dawley rat models of acute myocardial infarction (AMI) and in vitro myocardial angiogenesis, we showed that PEDF and 34-mer markedly inhibits angiogenesis by selectively inducing tip cells apoptosis rather than quiescent cells. Peptide 44-mer on the other hand exhibits no such effects. Next, we identified Fas death pathway as essential downstream regulators of PEDF and 34-mer activities in inhibiting angiogenesis. By using peroxisome proliferator-activated receptor γ (PPAR-γ) siRNA and PPAR-γ inhibitor, GW9662, we found the effects of PEDF and 34-mer were extensively blocked. These data suggest that PEDF and 34-mer inhibit angiogenesis via inducing tip cells apoptosis at least by means of up-regulating PPAR-γ to increase surface FasL in the ischemic heart, which might be a novel mechanism to understanding cardiac angiogenesis after AMI.


Assuntos
Proteínas do Olho/farmacologia , Proteína Ligante Fas/genética , Infarto do Miocárdio/genética , Neovascularização Fisiológica/efeitos dos fármacos , Fatores de Crescimento Neural/farmacologia , PPAR gama/genética , Peptídeos/farmacologia , Serpinas/farmacologia , Sequência de Aminoácidos , Anilidas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Proteína Ligante Fas/agonistas , Proteína Ligante Fas/metabolismo , Regulação da Expressão Gênica , Coração/efeitos dos fármacos , Coração/fisiopatologia , Dados de Sequência Molecular , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , PPAR gama/agonistas , PPAR gama/antagonistas & inibidores , PPAR gama/metabolismo , Peptídeos/síntese química , Cultura Primária de Células , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Serpinas/genética , Serpinas/metabolismo , Transdução de Sinais
13.
Biochem Biophys Res Commun ; 472(3): 482-8, 2016 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-26966066

RESUMO

Pigment epithelial-derived factor (PEDF) is a glycoprotein with broad biological activities including inhibiting oxygen-glucose deprivation(OGD)-induced cardiomyocytes apoptosis through its anti-oxidative properties. PEDF derived peptide-44mer shows similar cytoprotective effect to PEDF. However, the molecular mechanisms mediating cardiomyocytes apoptosis have not been fully established. Here we found that PEDF and 44mer decreased the content of ROS. This content was abolished by either PEDF-R small interfering RNA (siRNA) or PPARγ antagonist. The level of Lysophosphatidic acid (LPA) and phospholipase A2 (PLA2) was observed as drawn from the ELISA assays. PEDF and 44mer sequentially induced PPARγ expression was observed both in qPCR and Western blot assays. The level of LPA and PLA2 and PPARγ expression increased by PEDF and 44mer was significantly attenuated by PEDF-R siRNA. However, PEDF and 44mer inhibited the H9c2 cells and cultured neonatal rat myocardial cells apoptosis rate. On the other hand, TUNEL assay and cleavage of procaspase-3 showed that PEDF-R siRNA or PPARγ antagonist increased the apoptosis again. We conclude that under OGD condition, PEDF and 44mer reduce H9c2 cells apoptosis and inhibit OGD-induced oxidative stress via its receptor PEDF-R and the PPARγ signaling pathway.


Assuntos
Proteínas do Olho/metabolismo , Miócitos Cardíacos/metabolismo , Fatores de Crescimento Neural/metabolismo , Estresse Oxidativo/fisiologia , PPAR gama/metabolismo , Peptídeos/metabolismo , Receptores de Neuropeptídeos/metabolismo , Serpinas/metabolismo , Linhagem Celular , Glucose/metabolismo , Humanos , Peso Molecular , Miócitos Cardíacos/citologia , Oxigênio/metabolismo , Peptídeos/química , Regulação para Cima/fisiologia
14.
Cereb Cortex ; 25(7): 1735-45, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24436321

RESUMO

Thyroid hormone (TH) is essential for brain development both before and after birth. We have used gene expression microarrays to identify TH-regulated genes in the fetal cerebral cortex prior to the onset of fetal thyroid function to better understand the role of TH in early cortical development. TH levels were transiently manipulated in pregnant mice by treatment with goitrogens from gestational day (GD) 13-16 and/or by injection of TH 12 h before sacrifice on GD 16. The transcriptional response to exogenous TH in the GD 16 fetal cortex was potentiated by transient goitrogen treatment, suggesting that the hypothyroxinemic brain is a different substrate upon which TH can act, or that robust compensatory mechanisms are induced by transient hypothyroxinemia. Several known TH-responsive genes were identified including Klf9, and several novel TH-responsive genes such as Appbp2, Ppap2b, and Fgfr1op2 were identified in which TH response elements were confirmed. We also identified specific microRNAs whose expression in the fetal cortex was affected by TH treatment, and determined that Ppap2b and Klf9 are the target genes of miR-16 and miR-106, respectively. Thus, a complex redundant functional network appears to coordinate TH-mediated gene expression in the developing brain.


Assuntos
Córtex Cerebral/embriologia , Córtex Cerebral/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Hipotireoidismo/sangue , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Hormônios Tireóideos/administração & dosagem , Doença Aguda , Animais , Antitireóideos , Células Cultivadas , Modelos Animais de Doenças , Feminino , Camundongos Endogâmicos C57BL , Análise em Microsséries , Neuroblastoma/metabolismo , Gravidez , RNA Mensageiro/genética , Hormônios Tireóideos/sangue , Hormônios Tireóideos/metabolismo , Tiroxina/sangue , Transcrição Gênica
15.
Arch Toxicol ; 90(6): 1351-67, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26194646

RESUMO

Furan is a widely used industrial chemical and a contaminant in heated foods. Chronic furan exposure causes cholangiocarcinoma and hepatocellular tumors in rats at doses of 2 mg/kg bw/day or greater, with gender differences in frequency and severity. The hepatic transcriptional alterations induced by low doses of furan (doses below those previously tested for induction of liver tumors) and the potential mechanisms underlying gender differences are largely unexplored. We used DNA microarrays to examine the global hepatic mRNA and microRNA transcriptional profiles of male and female rats exposed to 0, 0.03, 0.12, 0.5 or 2 mg/kg bw/day furan over 90 days. Marked gender differences in gene expression responses to furan were observed, with many more altered genes in exposed males than females, confirming the increased sensitivity of males even at the low doses. Pathway analysis supported that key events in furan-induced liver tumors in males include gene expression changes related to oxidative stress, apoptosis and inflammatory response, while pathway changes in females were consistent with primarily adaptive responses. Pathway benchmark doses (BMDs) were estimated and compared to relevant apical endpoints. Transcriptional pathway BMDs could only be examined in males. These median BMDs ranged from 0.08 to 1.43 mg/kg bw/day and approximated those derived from traditional histopathology. MiR-34a (a P53 target) was the only microRNA significantly increased at the 2 mg/kg bw/day, providing evidence to support the importance of apoptosis and cell proliferation in furan hepatotoxicity. Overall, this study demonstrates the use of transcriptional profiling to discern mode of action and mechanisms involved in gender differences.


Assuntos
Carcinógenos Ambientais/toxicidade , Furanos/toxicidade , Fígado/efeitos dos fármacos , MicroRNAs/genética , RNA Mensageiro/genética , Transcrição Gênica/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Proliferação de Células/efeitos dos fármacos , Análise por Conglomerados , Relação Dose-Resposta a Droga , Feminino , Contaminação de Alimentos , Fígado/metabolismo , Fígado/patologia , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Ratos Endogâmicos F344 , Fatores Sexuais , Toxicogenética
16.
Int J Mol Sci ; 17(12)2016 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-27973457

RESUMO

The nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome has been linked to sterile inflammation, which is involved in ischemic injury in myocardial cells. Pigment epithelium-derived factor (PEDF) is a multifunctional secreted glycoprotein with many biological activities, such as anti-inflammatory, antioxidant and anti-angiogenic properties. However, it is not known whether and how PEDF acts to regulate the activation of the NLRP3 inflammasome in cardiomyocytes. In the present study, we used the neonatal cardiomyocytes models of ischemia-like conditions to evaluate the mitochondrial fission and the activation of the NLRP3 inflammasome. We also determined the mechanism by which PEDF inhibits hypoxia-induced activation of the NLRP3 inflammasome. We found that PEDF decreased the activation of the NLRP3 inflammasome in neonatal cardiomyocytes through pigment epithelial-derived factor receptor/calcium-independent phospholipase A2 (PEDFR/iPLA2). Meanwhile, PEDF reduced Drp1-induced mitochondrial fission and mitochondrial fission-induced mitochondrial DNA (mtDNA), as well as mitochondrial reactive oxygen species (mtROS) release into cytosol through PEDFR/iPLA2. We also found that PEDF inhibited mitochondrial fission-induced NLRP3 inflammasome activation. Furthermore, previous research has found that endogenous cytosolic mtDNA and mtROS can serve as activators of NLRP3 inflammasome activity. Therefore, we hypothesized that PEDF can protect against hypoxia-induced activation of the NLRP3 inflammasome by inhibiting mitochondrial fission though PEDFR/iPLA2.


Assuntos
Proteínas do Olho/farmacologia , Inflamassomos/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fatores de Crescimento Neural/farmacologia , Fosfolipases A2/metabolismo , Receptores de Neuropeptídeos/metabolismo , Serpinas/farmacologia , Animais , Animais Recém-Nascidos , Hipóxia Celular/efeitos dos fármacos , Células Cultivadas , DNA Mitocondrial/metabolismo , Inflamassomos/efeitos dos fármacos , Masculino , Dinâmica Mitocondrial/efeitos dos fármacos , Modelos Biológicos , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo
17.
Int J Mol Sci ; 17(5)2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-27187377

RESUMO

Pigment epithelial-derived factor (PEDF) is known as a widely expressed multifunctional secreted glycoprotein whose biological actions are cell-type dependent. Recent studies demonstrated that PEDF displays cytoprotective activity in several cell types. However, it remains unknown whether PEDF is involved in glucocorticoid-induced osteoblast death. The aim of this study was to examine the role of PEDF in osteoblast survival in response to dexamethasone, an active glucocorticoid analogue, and explore the underlying mechanism. In the present study, dexamethasone (DEX) was used to induce MC3T3-E1 pre-osteoblast apoptosis. PEDF mRNA and protein levels and cell apoptosis were determined respectively. Then PEDF receptor (PEDF-R)- and lysophosphatidic acid (LPA)-related signal transductions were assessed. Here we show that DEX down-regulates PEDF expression, which contributes to osteoblast apoptosis. As a result, exogenous recombinant PEDF (rPEDF) inhibited DEX-induced cell apoptosis. We confirmed that PEDF-R was expressed on MC3T3-E1 pre-osteoblast membrane and could bind to PEDF which increased the level of LPA and activated the phosphorylation of Akt. Our results suggest that PEDF attenuated DEX-induced apoptosis in MC3T3-E1 pre-osteoblasts through LPA-dependent Akt activation via PEDF-R.


Assuntos
Apoptose , Proteínas do Olho/metabolismo , Fatores de Crescimento Neural/metabolismo , Osteoblastos/metabolismo , Receptores de Neuropeptídeos/metabolismo , Serpinas/metabolismo , Animais , Linhagem Celular , Dexametasona/toxicidade , Proteínas do Olho/genética , Camundongos , Fatores de Crescimento Neural/genética , Osteoblastos/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serpinas/genética , Transdução de Sinais
18.
Biochem Biophys Res Commun ; 465(3): 394-401, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26277390

RESUMO

Pigment epithelial-derived factor (PEDF) is a multifunctional secreted glycoprotein, which could protect against hypoxia-induced cell death related to its anti-oxidative effect in cultured cardiomyocytes. However, the pathway mediating this cytoprotective process has not been fully established. Here we confirmed that PEDF bound to pigment epithelial-derived factor receptor (PEDF-R) expressed on the membrane of H9c2 cells. Under hypoxic condition, PEDF increased the ratio of MDM2:p53, so as to inhibited p53 mitochondrial translocation via PEDF-R. As a result, mitochondrial outer membrane permeabilization (MOMP) and mitochondrial permeability transition pore (MPTP) opening were inhibited, meanwhile cleaved caspase-3, PARP and the release of HMGB1 were reduced. Accordingly, apoptosis and necrosis were attenuated simultaneously. We conclude that PEDF-R mediates PEDF attenuates hypoxia-induced apoptosis and necrosis in H9c2 cells by inhibiting p53 mitochondrial translocation.


Assuntos
Proteínas do Olho/metabolismo , Mitocôndrias Cardíacas/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fatores de Crescimento Neural/metabolismo , Receptores de Neuropeptídeos/metabolismo , Serpinas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/fisiologia , Hipóxia Celular/fisiologia , Linhagem Celular , Mitocôndrias Cardíacas/patologia , Proteínas Mitocondriais/metabolismo , Necrose/patologia , Ratos
19.
J Transl Med ; 13: 68, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25890298

RESUMO

BACKGROUND: Pigment epithelium-derived factor (PEDF) is a 50-kDa secreted glycoprotein that is highly expressed in cardiomyocytes. A variety of peptides derived from PEDF exerts diverse physiological activities including anti-angiogenesis, antivasopermeability, and neurotrophic activities. Recent studies demonstrated that segmental functional peptides of PEDF, 44mer peptide (Val78-Thr121), show similar neurotrophic and cytoprotective effect to that of the holoprotein. We found that PEDF can reduce infarct size and protect cardiac function after acute myocardial infarction (AMI). However, the effects of PEDF on cardiac triglyceride (TG) accumulation after AMI remain unknown. The present study was performed to demonstrate the influence of PEDF and its functional peptides 44mer on TG degradation in AMI. METHODS: The left ascending coronary artery (LAD) was ligated to induce AMI. PEDF-small interfering RNA (siRNA)-lentivirus (PEDF-RNAi-LV) or PEDF-LV was delivered to the ischemic myocardium in order to knock down or overexpress PEDF, respectively. Oil Red O staining and a TG assay kit were used to analyze the TG content in cardiomyocytes and infarcted areas. RESULTS: The TG content significantly decreased in the PEDF-overexpressing heart compared to the sham group (P < 0.05). Both rPEDF and 44mer administration stimulate the TG degradation in cultured cardiomyocytes (P < 0.05). Adipose triglyceride lipase (ATGL)-specific inhibitor, atglistatin, attenuated the PEDF or 44mer-induced TG lipolysis activation of cardiomyocytes at 10 µmol/L. The effects of PEDF and 44mer on myocardial TG degradation were also abolished when ATGL was downregulated. CONCLUSIONS: We conclude that PEDF and 44mer promote TG degradation in cardiomyocytes after AMI via ATGL. The substitution of PEDF and 44mer may be a novel therapeutic strategy for cardiac TG accumulation after AMI.


Assuntos
Proteínas do Olho/metabolismo , Lipase/metabolismo , Miocárdio/metabolismo , Fatores de Crescimento Neural/metabolismo , Peptídeos/metabolismo , Serpinas/metabolismo , Triglicerídeos/metabolismo , Aciltransferases/genética , Aciltransferases/metabolismo , Sequência de Aminoácidos , Animais , Hipóxia Celular , Gotículas Lipídicas/metabolismo , Lipólise , Masculino , Dados de Sequência Molecular , Infarto do Miocárdio/complicações , Infarto do Miocárdio/patologia , Isquemia Miocárdica/complicações , Isquemia Miocárdica/patologia , Miocárdio/ultraestrutura , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Peptídeos/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley
20.
Tumour Biol ; 36(5): 3843-52, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25572678

RESUMO

The sex-determining region Y-box 4 (SOX4), a transcription factor, is involved in various developmental processes. It has been reported in multiple human cancers. However, the prognostic value and its exact role in chondrosarcoma remain poorly understood. In the current study, SOX4 was overexpressed in 28 of 92 (30.4 %) interpretable chondrosarcoma patients compared with 3 of 43 (6.9 %) interpretable chondroma cases (P = 0.003). Its overexpression in chondrosarcoma was significantly associated with histological grade (P < 0.001) and the presence of tumor recurrence (P = 0.041). In addition, SOX4 overexpression was notably correlated with c-MYC (P = 0.011) and P53 (P = 0.029) expression as well as high Ki67 labeling index (LI) (P < 0.001) in our cohort. More importantly, we found that SOX4 was an unfavorable independent prognostic factor for chondrosarcoma patients with low histological grade. Functionally, SOX4 silencing significantly suppressed the proliferation, migratory, and invasive capacity of SW1353 cells, suggesting an oncogenic role of SOX4 in chondrosarcoma in vitro. In an attempt of characterizing SOX4 overexpression mechanism, we identified miR-30a as a tumor suppressor that directly targets SOX4 in chondrosarcoma cells. Clinically, miR-30a expression was negatively correlated with SOX4 expression in chondrosarcoma cases. In all, we identified that SOX4 was oncogenic in chondrosarcoma and negatively regulated by miR-30a in vitro. Importantly, SOX4 overexpression may serve as a prognostic marker for patients with low-histological-grade chondrosarcoma.


Assuntos
Neoplasias Ósseas/genética , Condrossarcoma/genética , MicroRNAs/genética , Recidiva Local de Neoplasia/genética , Fatores de Transcrição SOXC/biossíntese , Adulto , Idoso , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Condrossarcoma/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/patologia , Prognóstico , Fatores de Transcrição SOXC/genética
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