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1.
Vet Res ; 55(1): 44, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589930

RESUMO

Swine acute diarrhea syndrome coronavirus (SADS-CoV), an emerging Alpha-coronavirus, brings huge economic loss in swine industry. Interferons (IFNs) participate in a frontline antiviral defense mechanism triggering the activation of numerous downstream antiviral genes. Here, we demonstrated that TRIM25 overexpression significantly inhibited SADS-CoV replication, whereas TRIM25 deficiency markedly increased viral yield. We found that SADS-CoV N protein suppressed interferon-beta (IFN-ß) production induced by Sendai virus (SeV) or poly(I:C). Moreover, we determined that SADS-CoV N protein interacted with RIG-I N-terminal two caspase activation and recruitment domains (2CARDs) and TRIM25 coiled-coil dimerization (CCD) domain. The interaction of SADS-CoV N protein with RIG-I and TRIM25 caused TRIM25 multimerization inhibition, the RIG-I-TRIM25 interaction disruption, and consequent the IRF3 and TBK1 phosphorylation impediment. Overexpression of SADS-CoV N protein facilitated the replication of VSV-GFP by suppressing IFN-ß production. Our results demonstrate that SADS-CoV N suppresses the host IFN response, thus highlighting the significant involvement of TRIM25 in regulating antiviral immune defenses.


Assuntos
Alphacoronavirus , Proteínas do Nucleocapsídeo , Animais , Suínos , Alphacoronavirus/metabolismo , Interferons/genética , Proteína DEAD-box 58/metabolismo
2.
Cell Signal ; 118: 111125, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38432574

RESUMO

BACKGROUND: Parkinson's disease patients on chronic levodopa often suffer from motor complications, which tend to reduce their quality of life. Levodopa-induced dyskinesia (LID) is one of the most prevalent motor complications, often characterized by abnormal involuntary movements, and the pathogenesis of LID is still unclear but recent studies have suggested the involvement of autophagy. METHODS: The onset of LID was mimicked by chronic levodopa treatment in a unilateral 6-hydroxydopamine (6-OHDA) -lesion rat model. Overexpression of ΔFosB in HEK293 cells to mimic the state of ΔFosB accumulation. The modulation of the AMP-activated protein kinase (AMPK)-mediated autophagy pathway using by metformin, AICAR (an AMPK activator), Compound C (an AMPK inhibitor) and chloroquine (an autophagy pathway inhibitor). The severity of LID was assessed by axial, limb, and orofacial (ALO) abnormal involuntary movements (AIMs) score and in vivo electrophysiology. The activity of AMPK pathway as well as autophagy markers and FosB-ΔFosB levels were detected by western blotting. RT-qPCR was performed to detect the transcription level of FosB-ΔFosB. The mechanism of autophagy dysfunction was further explored by immunofluorescence and transmission electron microscopy. RESULTS: In vivo experiments demonstrated that chronic levodopa treatment reduced AMPK phosphorylation, impaired autophagosome-lysosomal fusion and caused FosB-ΔFosB accumulation in the striatum of PD rats. Long-term metformin intervention improved ALO AIMs scores as well as reduced the mean power of high gamma (hγ) oscillations and the proportion of striatal projection neurons unstable in response to dopamine for LID rats. Moreover, the intervention of metformin promoted AMPK phosphorylation, ameliorated the impairment of autophagosome-lysosomal fusion, thus, promoting FosB-ΔFosB degradation to attenuate its accumulation in the striatum of LID rats. However, the aforementioned roles of metformin were reversed by Compound C and chloroquine. The results of in vitro studies demonstrated the ability of metformin and AICAR to attenuate ΔFosB levels by promoting its degradation, while Compound C and chloroquine could block this effect. CONCLUSIONS: In conclusion, our results suggest that long-term metformin treatment could promote ΔFosB degradation and thus attenuate the development of LID through activating the AMPK-mediated autophagy pathway. Overall, our results support the AMPK-mediated autophagy pathway as a novel therapeutic target for LID and also indicate that metformin is a promising therapeutic candidate for LID.


Assuntos
Discinesia Induzida por Medicamentos , Metformina , Humanos , Ratos , Animais , Levodopa/farmacologia , Levodopa/uso terapêutico , Antiparkinsonianos/farmacologia , Proteínas Quinases Ativadas por AMP , Células HEK293 , Qualidade de Vida , Discinesia Induzida por Medicamentos/tratamento farmacológico , Discinesia Induzida por Medicamentos/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Oxidopamina/uso terapêutico , Autofagia , Cloroquina/farmacologia , Cloroquina/uso terapêutico , Metformina/farmacologia , Modelos Animais de Doenças
3.
Bioengineering (Basel) ; 10(10)2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37892950

RESUMO

BACKGROUND: Breast cancer is one of the most common malignant tumors in women. A noninvasive ultrasound examination can identify mammary-gland-related diseases and is well tolerated by dense breast, making it a preferred method for breast cancer screening and of significant clinical value. However, the diagnosis of breast nodules or masses via ultrasound is performed by a doctor in real time, which is time-consuming and subjective. Junior doctors are prone to missed diagnoses, especially in remote areas or grass-roots hospitals, due to limited medical resources and other factors, which bring great risks to a patient's health. Therefore, there is an urgent need to develop fast and accurate ultrasound image analysis algorithms to assist diagnoses. METHODS: We propose a breast ultrasound image-based assisted-diagnosis method based on convolutional neural networks, which can effectively improve the diagnostic speed and the early screening rate of breast cancer. Our method consists of two stages: tumor recognition and tumor classification. (1) Attention-based semantic segmentation is used to identify the location and size of the tumor; (2) the identified nodules are cropped to construct a training dataset. Then, a convolutional neural network for the diagnosis of benign and malignant breast nodules is trained on this dataset. We collected 2057 images from 1131 patients as the training and validation dataset, and 100 images of the patients with accurate pathological criteria were used as the test dataset. RESULTS: The experimental results based on this dataset show that the MIoU of tumor location recognition is 0.89 and the average accuracy of benign and malignant diagnoses is 97%. The diagnosis performance of the developed diagnostic system is basically consistent with that of senior doctors and is superior to that of junior doctors. In addition, we can provide the doctor with a preliminary diagnosis so that it can be diagnosed quickly. CONCLUSION: Our proposed method can effectively improve diagnostic speed and the early screening rate of breast cancer. The system provides a valuable aid for the ultrasonic diagnosis of breast cancer.

4.
Artigo em Inglês | MEDLINE | ID: mdl-37742113

RESUMO

Aims: Epidemiological investigations have indicated low resistance toward nitrofuran in clinical isolates, suggesting its potential application in the treatment of multidrug-resistant bacteria. Therefore, it is valuable to explore the mechanism of bacterial resistance to nitrofuran. Results: Through phenotypic screening of ten multiple antibiotic resistance regulator (MarR) proteins in Vibrio cholerae, we discovered that the regulator VnrR (VCA1058) plays a crucial role in defending against nitrofuran, specifically furazolidone (FZ). Our findings demonstrate that VnrR responds to FZ metabolites, such as hydroxylamine, methylglyoxal, hydrogen peroxide (H2O2), ß-hydroxyethylhydrazine. Notably, VnrR exhibits reversible responses to the addition of H2O2 through three cysteine residues (Cys180, Cys223, Cys247), leading to the derepression of its upstream gene, vnrA (vca1057). Gene vnrA encodes a novel nitroreductase, which directly contributes to the degradation of FZ. Our study reveals that V. cholerae metabolizes FZ via the vnrR-vnrA system and achieves resistance to FZ with the assistance of the classical reactive oxygen/nitrogen species scavenging pathway. Innovation and Conclusion: This study represents a significant advancement in understanding the antibiotic resistance mechanisms of V. cholerae and other pathogens. Our findings demonstrate that the MarR family regulator, VnrR, responds to the FZ metabolite H2O2, facilitating the degradation and detoxification of this antibiotic in a thiol-dependent manner. These insights not only enrich our knowledge of antibiotic resistance but also provide new perspectives for the control and prevention of multidrug-resistant bacteria.

5.
Front Oncol ; 13: 1148131, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37384288

RESUMO

The incidence of gastric cancer is increasing year by year. Most gastric cancers are already in the advanced stage with poor prognosis when diagnosed, which means the current treatment is not satisfactory. Angiogenesis is an important link in the occurrence and development of tumors, and there are multiple anti-angiogenesis targeted therapies. To comprehensively evaluate the efficacy and safety of anti-angiogenic targeted drugs alone and in combination against gastric cancer, we systematically searched and sorted out relevant literature. In this review, we summarized the efficacy and safety of Ramucirumab, Bevacizumab, Apatinib, Fruquintinib, Sorafenib, Sunitinib, Pazopanib on gastric cancer when used alone or in combination based on prospective clinical trials reported in the literature, and sorted response biomarkers. We also summarized the challenges faced by anti-angiogenesis therapy for gastric cancer and available solutions. Finally, the characteristics of the current clinical research are summarized and suggestions and prospects are raised. This review will serve as a good reference for the clinical research of anti-angiogenic targeted drugs in the treatment of gastric cancer.

7.
Cell Mol Neurobiol ; 43(3): 1129-1146, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35635601

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that lasts lifelong and causes noticeably higher premature mortality. Although the core symptoms and other behavioral deficits of ASD can persist or be deteriorated from early development to old age, how aging affects the behaviors and brain anatomy in ASD is largely unknown. DOCK4 is an ASD risk gene highly expressed in the hippocampus, and Dock4 knockout (KO) mice display ASD-like behaviors in adulthood (4- to 6-month-old). In this study, we evaluated the behavioral and hippocampal pathological changes of late-middle-aged (15- to 17-month-old) Dock4 male KO mice. Aged Dock4 KO mice continuously showed similar social deficit, elevated anxiety, and disrupted object location memory as observed in the adulthood, when compared to their wild-type (WT) littermates. Notably, Dock4 KO mice displayed an age-related decline of hippocampal dependent spatial memory, showing decreased spatial memory in Barnes maze than their WT littermates at late middle age. Morphological analysis from WT and Dock4 KO littermates revealed that Dock4 deficiency led to decreased mature neurons and oligodendrocytes but increased astrocytes in the hippocampus of late-middle-aged mice. Together, we report that ASD-like behaviors mostly persist into late-middle age in Dock4 KO mice, with specific alterations of spatial memory and hippocampal anatomy by age, thus providing new evidence for understanding age differences in behavioral deficits of ASD.


Assuntos
Hipocampo , Transtornos da Memória , Masculino , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Envelhecimento , Transtornos da Memória/genética , Transtornos da Memória/metabolismo , Transtornos da Memória/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Comportamento Animal , Aprendizagem em Labirinto , Transtornos do Comportamento Social/genética , Transtornos do Comportamento Social/metabolismo , Ansiedade/genética , Ansiedade/metabolismo , Transtornos Neurológicos da Marcha/genética , Transtornos Neurológicos da Marcha/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Transtorno Autístico/genética , Transtorno Autístico/metabolismo
8.
BMC Womens Health ; 22(1): 412, 2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-36209087

RESUMO

BACKGROUND: MicroRNAs are a type of non-coding single-stranded RNA, which is involved in the regulation of ovary insulin resistance (IR). This study aims to explore the underlying mechanisms of miR-133a-3p regulating ovary IR in obese polycystic ovary syndrome (PCOS). METHODS: Granulosa cells (GCs) were extracted from follicular fluids of PCOS patients (obese PCOS group and non-obese PCOS group) and healthy women (control group). The expression of miR-133a-3p in GCs was detected by qRT-PCR. The targets and pathways of miR-133a-3p were predicted by bioinformatics analyses. The protein levels of PI3K, p-AKT, GLUT4, p-GSK-3ß, and p-FOXO1 were measured by Western blotting. RESULTS: MiR-133a-3p was highly expressed in GCs from PCOS patients, especially in obese PCOS patients. The protein levels of PI3K and p-AKT was downregulated in GCs from PCOS patients. There were 11 target genes of miR-133a-3p enriching in PI3K/AKT signaling pathway. miR-133a-3p mimic downregulated the expression of PI3K, p-AKT, and GLUT4, and upregulated the protein levels of p-GSK-3ß and p-FOXO1. miR-133a-3p inhibitor presented the opposite effect of miR-133a-3p mimic. CONCLUSION: MiR-133a-3p promotes ovary IR on GCs of obese PCOS patients via inhibiting PI3K/AKT signaling pathway. This study lays a foundation for further research on the mechanism of ovary IR in obese PCOS patients.


Assuntos
Resistência à Insulina , MicroRNAs , Síndrome do Ovário Policístico , Feminino , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/farmacologia , Células da Granulosa/metabolismo , Humanos , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/farmacologia , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/farmacologia , Transdução de Sinais/fisiologia , Regulação para Cima
9.
J Parkinsons Dis ; 12(7): 2097-2116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35912751

RESUMO

BACKGROUND: Pathological changes in the brain can affect the gastrointestinal tract, whereas there is less evidence regarding the brain-gut axis. OBJECTIVE: To identify whether cerebral endogenous phosphorylated α-synuclein induces gastrointestinal dysfunction via the brain-gut axis, mediated by the vagus nerve. METHODS: α-syn N103/tau N368 preformed fibrils were injected into the dorsal lateral striatum of rodents, and the cerebral and colonic synucleinopathies and changes in the enteric nervous system were analyzed. Moreover, subdiaphragmatic vagotomy was conducted to confirm the role of the vagus nerve in brain-gut propagation. RESULTS: An anterograde propagation of phosphorylated α-synuclein from the brain to the proximal colon mainly via the vagus nerve was observed at one month. The accumulation of phosphorylated α-synuclein was detected in the proximal colon over time, accompanied by infiltration of macrophages and eosinophils in the mucosa and submucosa. Upon injection with lower doses of preformed fibrils, the accumulation of phosphorylated α-synuclein and dopaminergic neuron loss was reduced to levels consistent with control at six months, while the expression levels of GFAP, Iba-1, and IL-6 increased. Under high preformed fibrils dose conditions, fecal traits and gastrointestinal motility were significantly reduced at six months, and aggregations of phosphorylated α-synuclein and an increasing level of IL-1ß appeared. CONCLUSION: Induced endogenous α-synuclein can quickly propagate into the proximal colon mainly via the vagus nerve. Injections of low doses of preformed fibrils can elicit recovery of the enteric nervous system and degradation of α-synuclein aggregates whereas high doses cause accumulation of pathological α-synuclein, enteric inflammation, and prominent gastrointestinal dysfunction.


Assuntos
Gastroenteropatias , Doença de Parkinson , Sinucleinopatias , Animais , Colo , Interleucina-6 , Roedores , alfa-Sinucleína/metabolismo
10.
PLoS Pathog ; 17(7): e1009763, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34283874

RESUMO

Sensing and resisting oxidative stress is critical for Vibrio cholerae to survive in either the aquatic environment or the gastrointestinal tract. Previous studies mainly focused on the mechanisms of oxidative stress response regulation that rely on enzymatic antioxidant systems, while functions of non-enzymatic antioxidants are rarely discussed in V. cholerae. For the first time, we investigated the role of hydrogen sulfide (H2S), the simplest thiol compound, in protecting V. cholerae against oxidative stress. We found that degradation of L-cysteine by putative cystathionine ß-synthase (CBS) is the major source of endogenous H2S in V. cholerae. Our results indicate that intracellular H2S level has a positive correlation with cbs expression, while the enhanced H2S production can render V. cholerae cells less susceptible to H2O2 in vitro. Using proteome analysis and real-time qPCR assay, we found that cbs expression could stimulate the expression of several enzymatic antioxidants, including reactive oxygen species (ROS) detoxifying enzymes SodB, KatG and AhpC, the DNA protective protein DPS and the protein redox regulator Trx1. Assays of ROS detoxification capacities revealed that CBS-derived H2S could promote catalase activity at the post-translational level, especially for KatB, which serves as an important way that endogenous H2S participates in H2O2 detoxification. The enhancement of catalase activity by H2S is achieved through facilitating the uptake of iron. Adult mice experiments showed that cbs mutant has colonization defect, while either complementation of cbs or exogenous supplement of N-Acetyl-L-Cysteine restores its fitness in the host environment. Herein, we proposed that V. cholerae regulates CBS-dependent H2S production for better survival and proliferation under ROS stress.


Assuntos
Cistationina beta-Sintase/metabolismo , Interações Hospedeiro-Patógeno/fisiologia , Sulfeto de Hidrogênio/metabolismo , Cinesinas/metabolismo , Vibrio cholerae/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Catalase/metabolismo , Cólera/metabolismo , Camundongos , Estresse Oxidativo/fisiologia , Vibrio cholerae/patogenicidade
11.
Sci Bull (Beijing) ; 66(18): 1906-1916, 2021 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36654400

RESUMO

Icaritin is a prenylflavonoid present in the Chinese herbal medicinal plant Epimedium spp. and is under investigation in a phase III clinical trial for advanced hepatocellular carcinoma. Here, we report the biosynthesis of icaritin from glucose by engineered microbial strains. We initially designed an artificial icaritin biosynthetic pathway by identifying a novel prenyltransferase from the Berberidaceae-family species Epimedium sagittatum (EsPT2) that catalyzes the C8 prenylation of kaempferol to yield 8-prenlykaempferol and a novel methyltransferase GmOMT2 from soybean to transfer a methyl to C4'-OH of 8-prenlykaempferol to produce icaritin. We next introduced 11 heterologous genes and modified 12 native yeast genes to construct a yeast strain capable of producing 8-prenylkaempferol with high efficiency. GmOMT2 was sensitive to low pH and lost its activity when expressed in the yeast cytoplasm. By relocating GmOMT2 into mitochondria (higher pH than cytoplasm) of the 8-prenylkaempferol-producing yeast strain or co-culturing the 8-prenylkaempferol-producing yeast with an Escherichia coli strain expressing GmOMT2, we obtained icaritin yields of 7.2 and 19.7 mg/L, respectively. Beyond the characterizing two previously unknown plant enzymes and conducting the first biosynthesis of icaritin from glucose, we describe two strategies of overcoming the widespread issue of incompatible pH conditions encountered in basic and applied bioproduction research. Our findings will facilitate industrial-scale production of icaritin and other prenylflavonoids.


Assuntos
Neoplasias Hepáticas , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/genética , Escherichia coli/genética , Neoplasias Hepáticas/metabolismo , Glucose/metabolismo
12.
Behav Brain Res ; 393: 112786, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32592738

RESUMO

Parkinson's disease has become one of the most common neurodegenerative diseases. Pathological changes typically manifest following dopaminergic neuron loss in the substantia nigra and abnormal alpha-synuclein (α-syn) aggregation in the neurons. α-Syn is the major component of Lewy bodies. However, research pertaining to the spread of abnormal α-syn aggregations, which results in specific damage to the brain structure and function, is lacking. In the present study, full-length human α-syn fibrils were injected into the medial forebrain bundle of rats, with an experimental endpoint of 6 months. Histological analysis was conducted to observe the pathological progress of abnormal endogenous α-syn aggregation and nerve fiber quality. Changes in gray and white matter integrity were quantitatively analyzed using voxel-based morphometry (VBM). Behavioral changes were observed over the 6-month period. Histological analysis showed reduced dopamine transporter levels in the striatum of the experimental rats; widespread abnormal endogenous α-syn accumulation; and damaged, sparse, and disordered nerve fibers in the experimental group. VBM showed that at 6 months after surgery, bilateral anterior limbic, bilateral inferior limbic, right hippocampal, and right cortical volumes had reduced, whereas thalamic volume had increased in the experimental group compared with that in the control group. Damage to the limbic and thalamic fiber structure may occur in the earlier stages of Parkinson's disease.


Assuntos
Encéfalo/patologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Agregação Patológica de Proteínas , Serina/metabolismo , alfa-Sinucleína/metabolismo , Animais , Modelos Animais de Doenças , Masculino , Feixe Prosencefálico Mediano/metabolismo , Fosforilação , Ratos Sprague-Dawley
13.
Exp Ther Med ; 18(2): 1221-1225, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31316617

RESUMO

Nuclear factor-κB interacting long non-coding RNA (LncRNA NKILA) is a well-studied tumor suppressor lncRNA in several types of malignancies. The present study reports the involvement of this lncRNA in diabetic cardiomyopathy (DC). A 8-year-follow-up study on 312 diabetic patients without exhibiting obvious complications demonstrated that plasma lncRNA NKILA levels were upregulated specifically in diabetic patients who developed DC but not in patients with other complications. Plasma levels of lncRNA NKILA at 6 months prior to diagnosis is sufficient to distinguish patients with DC from other diabetic patients without significant complications. Although in vitro experiments demonstrated that lncRNA NKILA expression in cardiomyocyte cells was not affected by high-glucose treatment, ectopic lncRNA NKILA expression and lncRNA NKILA knockdown potentiated, and inhibited cardiomyocyte apoptosis, respectively. Therefore, the data from the present study suggests that overexpression of lncRNA NKILA is involved in DC, and overexpression of lncRNA NKILA may serve as a therapeutic target for treating DC.

14.
Free Radic Biol Med ; 84: 171-184, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25857215

RESUMO

Litchi leaf is a good resource for phenolics, which are good candidates for medicines. In this work, three phenolics were isolated from litchi leaf by column chromatography. Their structures were identified by electrospray ionization-mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR) spectroscopy as secoisolariciresinol 9'-O-ß-D-xyloside (1), 4,7,7',8',9,9'-hexahydroxy-3,3'-dimethoxy-8,4'-oxyneolignan (2), and cinnamtannin B1 (3). Cinnamtannin B1 showed better extra- and intracellular antioxidant activities than Compounds 1 and 2. The intracellular antioxidant activity of cinnamtannin B1 was related to the upregulation of endogenous antioxidant enzyme activities (superoxide dismutase, catalase, and glutathione peroxidase), and inhibition of ROS generation. Furthermore, cinnamtannin B1 exhibited strong antiproliferative effects against HepG2 and Siha cell lines with no significant cytotoxicities. In the case of the HepG2 cell line, cell cycle arrest and apoptosis induction were the underlying anticancer mechanisms of cinnamtannin B1. The results indicated that cinnamtannin B1 was a potent cancer cell proliferation inhibitor and a good intracellular antioxidant.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sequestradores de Radicais Livres/farmacologia , Litchi/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Sequestradores de Radicais Livres/química , Frutas/química , Pontos de Checagem da Fase G1 do Ciclo Celular , Células Hep G2 , Humanos , Concentração Inibidora 50 , Oxirredução , Fenóis/química , Extratos Vegetais/química , Proantocianidinas/farmacologia
15.
Mol Med Rep ; 9(5): 1590-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24573187

RESUMO

Currently, there is major interest in the functions of apelin-13, an endogenous ligand for the orphan G-protein coupled receptor APJ, a receptor that closely resembles the angiotensin receptor AT1. In the present study, the role of apelin-13 in angiogenesis and its mechanism as a novel angiogenic factor in myocardial microvascular endothelial cells (MMVECs) was investigated. It was revealed that apelin-13 can promote proliferation, migration and tube formation in MMVECs. In addition, apelin-13 dose dependently stimulated the phosphorylation of AMP-activated protein kinase (AMPK) and endothelial nitric oxide synthase (eNOS) at Thr-172 and Ser-1179, respectively. The treatment with the AMPK (compound C) and protein kinase Akt/protein kinase B (Akt; LY294002) inhibitor significantly suppressed the apelin­13-induced AMPK, Akt and eNOS phosphorylation. They also inhibited the apelin13­stimulated endothelial cell migration and tube formation. Therefore, we hypothesize that apelin-13 promotes angiogenesis through the modulation of AMPK and Akt signaling in MMVECs.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Endoteliais/citologia , Fosforilação/efeitos dos fármacos , Ratos
16.
Proc Natl Acad Sci U S A ; 108(7): 2807-12, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21282641

RESUMO

The vasculature of the CNS is structurally and functionally distinct from that of other organ systems and is particularly prone to developmental abnormalities and hemorrhage. Although other embryonic tissues undergo primary vascularization, the developing nervous system is unique in that it is secondarily vascularized by sprouting angiogenesis from a surrounding perineural plexus. This sprouting angiogenesis requires the TGF-ß and Wnt pathways because ablation of these pathways results in aberrant sprouting and hemorrhage. We have genetically deleted Gpr124, a member of the large family of long N-terminal group B G protein-coupled receptors, few members of which have identified ligands or well-defined biologic functions in mammals. We show that, in the developing CNS, Gpr124 is specifically expressed in the vasculature and is absolutely required for proper angiogenic sprouting into the developing neural tube. Embryos lacking Gpr124 exhibit vascular defects characterized by delayed vascular penetration, formation of pathological glomeruloid tufts within the CNS, and hemorrhage. In addition, they display defects in palate and lung development, two processes in which TGF-ß and/or Wnt pathways also play important roles. We also show that TGF-ß stimulates Gpr124 expression, and ablation of Gpr124 results in perturbed TGF-ß pathway activation, suggesting roles for Gpr124 in modulating TGF-ß signaling. These results represent a unique function attributed to a long N-terminal group B-type G protein-coupled receptor in a mammalian system.


Assuntos
Sistema Nervoso Central/irrigação sanguínea , Sistema Nervoso Central/embriologia , Neovascularização Fisiológica/fisiologia , Receptores Acoplados a Proteínas G/metabolismo , Animais , Embrião de Mamíferos , Engenharia Genética , Técnicas Histológicas , Imuno-Histoquímica , Hibridização In Situ , Pulmão/embriologia , Pulmão/metabolismo , Camundongos , Análise em Microsséries , Palato/embriologia , Palato/metabolismo , Receptores Acoplados a Proteínas G/deficiência , Receptores Acoplados a Proteínas G/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Proteínas Wnt/metabolismo
17.
Shock ; 31(5): 493-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-18791492

RESUMO

The complement C5a pathway has been shown to be an important mediator of inflammation and tissue injury. To further understand the role of C5a receptor (C5aR) pathway in ischemia/reperfusion (I/R) injury, and to evaluate the potential of antagonizing C5aR to protect from I/R injury, we tested the effect of eliminating C5aR using C5aR knockout (KO) mice and their wild-type (WT) littermates in a superior mesenteric artery occlusion (SMAO) intestinal I/R injury model. C5aR KO and WT mice were subjected to SMAO or sham for 45 min. After 3 h of reperfusion, the percentage of injured ileal villi was twice as high in WT mice subjected to SMAO as compared with the C5aR KO mice. In addition, the number of neutrophils was 34% higher in WT mice subjected to SMAO as compared with the C5aR KO mice. Moreover, ileum and lung myeloperoxidase activities after SMAO were significantly higher in WT than C5aR KO mice. Apoptotic cell death was induced after reperfusion in WT-SMAO and was reduced by more than 50% in C5aR KO mice. The plasma level of TNF-alpha was increased approximately 3.74-fold in WT subjected to SMAO compared with sham. In contrast, the level was increased only approximately 1.18-fold in the C5aR KO mice subjected to SMAO. In conclusion, this study demonstrates that elimination of the C5aR pathway protects the intestine from I/R injury and diminishes intestine-derived pulmonary neutrophil sequestration. Blocking C5aR may be considered as a potential therapeutic intervention for I/R injury.


Assuntos
Mucosa Intestinal/irrigação sanguínea , Infiltração de Neutrófilos/fisiologia , Receptor da Anafilatoxina C5a/fisiologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Apoptose , Modelos Animais de Doenças , Íleo/irrigação sanguínea , Íleo/metabolismo , Mucosa Intestinal/metabolismo , Pulmão/irrigação sanguínea , Pulmão/metabolismo , Camundongos , Camundongos Knockout , Infiltração de Neutrófilos/genética , Peroxidase/metabolismo , Receptor da Anafilatoxina C5a/genética , Traumatismo por Reperfusão/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/sangue
18.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 23(4): 478-81, 2007 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-21180138

RESUMO

AIM: To investigate effects of hsBAFF synthesized in Escherichia coli on spleen B lymphocyte immune response and its intracellular free Ca2+ ([Ca2]i]) signaling in mice. METHODS: Twenty ICR mice, half males-half females, were chosen and randomly divided into a normal control group (n=10) and a hsBAFF treatment group (n-10). The mice in hsBAFF treatment group were given abdominal cavity injection of hsBAFF solution which was diluted with phosphate buffered saline (PBS) at dosage of 0.1 mg/kg body weight once each day for over eight days. The mice in control group were received abdominal injection of PBS at the same dose and frequency. Spleen B lymphocyte proliferation and its immune response to LPS stimulation in mice were evaluated using an MTT assay, and change of spleen B lymphocyte [Ca2+]i was assayed under a laser scanning confocal microscope. RESULTS: B lymphocyte proliferation and its immune response to LPS stimulation were significantly higher in hsBAFF-treated mice than in control mice (P < 0.05). The B lymphocyte [Ca2+]i fluorescence intensity in hsBAFF-treated mice maintained at a relatively high level fluctuation, and its average intensity was significantly higher to that of control mice (P < 0.01), but change rate of the intensity was lower compared to that of control group. CONCLUSION: hsBAFF synthesized in Escherichia coli can enhance immune function in the body by increasing B lymphocyte proliferation and its immune response. hsBAFF-activated B lymphocyte function may be associated with increasing B lymphocytes [Ca2+]i.


Assuntos
Fator Ativador de Células B/farmacologia , Linfócitos B/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Baço/efeitos dos fármacos , Animais , Fator Ativador de Células B/imunologia , Linfócitos B/citologia , Linfócitos B/imunologia , Cálcio/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos ICR , Baço/citologia , Baço/imunologia
19.
Diabetes ; 54(3): 672-8, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15734842

RESUMO

Increased visceral adiposity is a pivotal component of the metabolic syndrome. Differential gene expression patterns of fat-derived peptides (FDPs) in visceral fat and subcutaneous fat have been characterized in the fasting state. Here we examined whether delivery of nutrients differentially affects the expression of FDPs in visceral fat versus subcutaneous fat (in the fed state). We increased the rate of glucose flux into adipose tissue of normal rats (n = 16) by hyperglycemia or hyperinsulinemia using the clamp technique. Glucose uptake was associated with increased expression of FDPs, including resistin ( approximately 5-fold), adiponectin ( approximately 2-fold), leptin ( approximately 15-fold), plasminogen activating inhibitor-1 ( approximately 10-fold), and angiotensinogen ( approximately 4-fold) in visceral fat, but markedly less in subcutaneous fat. Cytokine expression derived mainly from vascular/stromal/macrophage components of adipose tissue was less dramatically increased. Infusion of glucosamine amplified the results obtained by increasing glucose uptake into adipose tissue, suggesting that flux through the hexosamine biosynthetic pathway may serve as a mechanism for "nutrient sensing." Nutrient-dependent expression of FDPs in visceral fat was also associated with increased plasma levels of several FDPs. Because a biologic sensing pathway can dynamically couple daily food intake to abnormal plasma levels of important FDPs, we challenge the practice of obtaining plasma levels after fasting to assess risk factors for metabolic syndrome.


Assuntos
Tecido Adiposo/metabolismo , Peptídeos/metabolismo , Tecido Adiposo/efeitos dos fármacos , Animais , Expressão Gênica , Glucosamina/farmacologia , Glucose/metabolismo , Técnica Clamp de Glucose , Técnicas In Vitro , Insulina/farmacologia , Ratos
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