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1.
J Med Internet Res ; 23(10): e32328, 2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34543228

RESUMO

BACKGROUND: The COVID-19 pandemic has increased the importance of the deployment of digital detection surveillance systems to support early warning and monitoring of infectious diseases. These opportunities create a "double-edge sword," as the ethical governance of such approaches often lags behind technological achievements. OBJECTIVE: The aim was to investigate ethical issues identified from utilizing artificial intelligence-augmented surveillance or early warning systems to monitor and detect common or novel infectious disease outbreaks. METHODS: In a number of databases, we searched relevant articles that addressed ethical issues of using artificial intelligence, digital surveillance systems, early warning systems, and/or big data analytics technology for detecting, monitoring, or tracing infectious diseases according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, and further identified and analyzed them with a theoretical framework. RESULTS: This systematic review identified 29 articles presented in 6 major themes clustered under individual, organizational, and societal levels, including awareness of implementing digital surveillance, digital integrity, trust, privacy and confidentiality, civil rights, and governance. While these measures were understandable during a pandemic, the public had concerns about receiving inadequate information; unclear governance frameworks; and lack of privacy protection, data integrity, and autonomy when utilizing infectious disease digital surveillance. The barriers to engagement could widen existing health care disparities or digital divides by underrepresenting vulnerable and at-risk populations, and patients' highly sensitive data, such as their movements and contacts, could be exposed to outside sources, impinging significantly upon basic human and civil rights. CONCLUSIONS: Our findings inform ethical considerations for service delivery models for medical practitioners and policymakers involved in the use of digital surveillance for infectious disease spread, and provide a basis for a global governance structure. TRIAL REGISTRATION: PROSPERO CRD42021259180; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=259180.


Assuntos
COVID-19 , Doenças Transmissíveis , Inteligência Artificial , Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/epidemiologia , Humanos , Pandemias , SARS-CoV-2
2.
Pharmacol Res ; 157: 104840, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32353589

RESUMO

Hepatocyte nuclear factor 4 alpha (HNF4α) regulates the expression of essential genes involved in very-low-density lipoprotein (VLDL) homeostasis and gluconeogenesis. 18ß-glycyrrhetinic acid (GA) is an active ingredient of Glycyrrhiza uralensis an herbal medicine used for treating liver aliments. In this study, we established that GA functions as a partial antagonist of HNF4α through HNF4α-driven reporter luciferase assay and co-immunoprecipitation experiments with co-activator PGC1α. By virtual docking and site-directed mutagenesis analysis, we confirmed that serine 190 and arginine 235 of HNF4α are both essential for GA to exert its antagonistic action on HNF4α. Importantly, GA suppressed the expression of HNF4α target genes such as apolipoprotein B (ApoB), microsomal triglyceride transfer protein (MTP) and phospholipase A2 G12B (PLA2G12B) modulating hepatic VLDL secretion in mice fed on a high fat diet. In addition, GA also suppressed gluconeogenesis and ameliorated glucose intolerance via down-regulating the expression of HNF4α target genes glucose-6-phosphatase (G6pc) and phosphoenolpyruvate carboxykinase (Pepck). Furthermore, GA significantly lowered blood glucose and improved insulin resistance in db/db mice. In all, we established that GA acts as a partial HNF4α antagonist modulating lipid and carbohydrate metabolism.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus/tratamento farmacológico , Ácido Glicirretínico/análogos & derivados , Fator 4 Nuclear de Hepatócito/antagonistas & inibidores , Hepatócitos/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Hipolipemiantes/farmacologia , Lipídeos/sangue , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Animais , Glicemia/metabolismo , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Gluconeogênese/efeitos dos fármacos , Ácido Glicirretínico/farmacologia , Células HEK293 , Fator 4 Nuclear de Hepatócito/genética , Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Resistência à Insulina , Masculino , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Transdução de Sinais
3.
Hum Reprod ; 32(4): 733-742, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28175305

RESUMO

Study question: Are multimeric sperm plasma membrane protein complexes, ERp57 and sperm surface thiol content involved in human spermatozoa-zona pellucida (ZP) interaction? Summary answer: ERp57 is a component of a multimeric spermatozoa-ZP receptor complex involved in regulation of human spermatozoa-ZP binding via up-regulation of sperm surface thiol content. What is known already: A spermatozoon acquires its fertilization capacity within the female reproductive tract by capacitation. Spermatozoa-ZP receptor is suggested to be a composite structure that is assembled into a functional complex during capacitation. Sperm surface thiol content is elevated during capacitation. ERp57 is a protein disulphide isomerase that modulates the thiol-disulphide status of proteins. Study design, size, duration: The binding ability and components of protein complexes in extracted membrane protein fractions of spermatozoa were studied. The roles of capacitation, thiol-disulphide reagent treatments and ERp57 on sperm functions and sperm surface thiol content were assessed. Participants/materials, setting, methods: Spermatozoa were obtained from semen samples from normozoospermic men. Human oocytes were obtained from an assisted reproduction programme. Blue native polyacrylamide gel electrophoresis, western ligand blotting and mass spectrometry were used to identify the components of solubilized ZP/ZP3-binding complexes. The localization and expression of sperm surface thiol and ERp57 were studied by immunostaining and sperm surface protein biotinylation followed by western blotting. Sperm functions were assessed by standard assays. Main results and the role of chance: Several ZP-binding complexes were isolated from the cell membrane of capacitated spermatozoa. ERp57 was a component of one of these complexes. Capacitation significantly increased the sperm surface thiol content, acrosomal thiol distribution and ERp57 expression on sperm surface. Sperm surface thiol and ERp57 immunoreactivity were localized to the acrosomal region of spermatozoa, a region responsible for ZP-binding. Up-regulation of the surface thiol content or ERp57 surface expression in vitro stimulated ZP-binding capacity of human spermatozoa. Blocking of ERp57 function by specific antibody or inhibitors against ERp57 reduced the surface thiol content and ZP-binding capacity of human spermatozoa. Large scale data: N/A. Limitations, reasons for caution: The mechanisms by which up-regulation of surface thiol content stimulates spermatozoa-ZP binding have not been depicted. Wider implications of the findings: Thiol-disulphide exchange is a crucial event in capacitation. ERp57 modulates the event and the subsequent fertilization process. Modulation of the surface thiol content of the spermatozoa of subfertile men may help to increase fertilization rate in assisted reproduction. Study funding/competing interest(s): This work was supported by The Hong Kong Research Grant Council Grant HKU764611 and HKU764512M to P.C.N.C. The authors have no competing interests.


Assuntos
Isomerases de Dissulfetos de Proteínas/fisiologia , Interações Espermatozoide-Óvulo , Compostos de Sulfidrila/metabolismo , Acrossomo/metabolismo , Feminino , Humanos , Masculino , Isomerases de Dissulfetos de Proteínas/genética , Capacitação Espermática , Espermatozoides/metabolismo , Compostos de Sulfidrila/análise , Regulação para Cima , Zona Pelúcida/metabolismo
4.
Molecules ; 22(5)2017 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-28445411

RESUMO

The pentacyclic triterpene oleanolic acid (OA, 1) with known farnesoid X receptor (FXR) modulatory activity was modified at its C-3 position to find new FXR-interacting agents. A diverse substitution library of OA derivatives was constructed in silico through a 2D fingerprint similarity cluster strategy. With further docking analysis, four top-scored OA 3-O-ester derivatives were selected for synthesis. The bioassay results indicated that all four compounds 3 inhibited chenodeoxycholic acid (CDCA)-induced FXR transactivation in a concentration-dependent mode. Among them 3b and 3d are more active than the parent compound OA. A molecular simulation study was performed to attempt to explain the structure-activity relationship (SAR) and the antagonistic action. To the best of our knowledge, this is the first report on semi-synthetic pentacyclic triterpenoids with FXR-modulatory activities.


Assuntos
Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Receptores Citoplasmáticos e Nucleares/química , Sítios de Ligação , Avaliação Pré-Clínica de Medicamentos , Células HEK293 , Humanos , Ligação de Hidrogênio , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Ácido Oleanólico/farmacologia , Ligação Proteica , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/metabolismo , Relação Estrutura-Atividade
5.
Nat Commun ; 15(1): 3769, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704393

RESUMO

Excessive bone marrow adipocytes (BMAds) accumulation often occurs under diverse pathophysiological conditions associated with bone deterioration. Estrogen-related receptor α (ESRRA) is a key regulator responding to metabolic stress. Here, we show that adipocyte-specific ESRRA deficiency preserves osteogenesis and vascular formation in adipocyte-rich bone marrow upon estrogen deficiency or obesity. Mechanistically, adipocyte ESRRA interferes with E2/ESR1 signaling resulting in transcriptional repression of secreted phosphoprotein 1 (Spp1); yet positively modulates leptin expression by binding to its promoter. ESRRA abrogation results in enhanced SPP1 and decreased leptin secretion from both visceral adipocytes and BMAds, concertedly dictating bone marrow stromal stem cell fate commitment and restoring type H vessel formation, constituting a feed-forward loop for bone formation. Pharmacological inhibition of ESRRA protects obese mice against bone loss and high marrow adiposity. Thus, our findings highlight a therapeutic approach via targeting adipocyte ESRRA to preserve bone formation especially in detrimental adipocyte-rich bone milieu.


Assuntos
Adipócitos , Medula Óssea , Leptina , Osteogênese , Receptores de Estrogênio , Animais , Osteogênese/genética , Adipócitos/metabolismo , Adipócitos/citologia , Camundongos , Leptina/metabolismo , Leptina/genética , Medula Óssea/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Estrogênio/genética , Células-Tronco Mesenquimais/metabolismo , Obesidade/metabolismo , Obesidade/patologia , Obesidade/genética , Receptor ERRalfa Relacionado ao Estrogênio , Receptor alfa de Estrogênio/metabolismo , Receptor alfa de Estrogênio/genética , Feminino , Masculino , Camundongos Endogâmicos C57BL , Transdução de Sinais , Células da Medula Óssea/metabolismo , Camundongos Knockout
6.
Br J Gen Pract ; 74(suppl 1)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902080

RESUMO

BACKGROUND: Older adults with multimorbidity are at high risk of mortality following COVID-19 hospitalisation. However, the potential benefit of timely primary care follow-up on severe outcomes post-COVID-19 has not been well established. AIM: To examine the effectiveness of attending general outpatient within 30 days after discharge from COVID-19 on 1-year survival among older adults aged ≥85 years, with multimorbidity. METHOD: We emulated a target trial using a comprehensive public healthcare database in Hong Kong. The cloning-censoring-weighting technique was used to minimise immortal time bias and confounding bias by adjusting for demographics, hospitalisation duration and ICU admission, baseline chronic conditions, and medication history. The outcome included all-cause and cause-specific mortality. RESULTS: Of 6183 eligible COVID-19 survivors, the all-cause mortality rate following COVID-19 hospitalisation was lower in general out-patient clinics (GOPC) group compared to non-GOPC group (17.1 versus 42.8 deaths per 100 person-year). After adjustment, primary care consultations within 30 days after discharge were associated with a significantly greater 1-year survival (difference in 1-year survival: 11.2%, 95% CI = 8.1% to 14.4%). We also observed better survival from respiratory diseases in the GOPC group. In a sensitivity analysis for different grace period lengths, we found that the earlier participants had a GOPC visit after COVID-19 discharge, the better the survival. CONCLUSION: Timely primary care consultations after discharge may improve survival following COVID-19 hospitalisation among older adults aged ≥85 years, with multimorbidity. Expanding primary care services and implementing follow-up mechanisms are crucial to support this vulnerable population's recovery and well-being.


Assuntos
COVID-19 , Multimorbidade , Atenção Primária à Saúde , SARS-CoV-2 , Humanos , COVID-19/mortalidade , COVID-19/epidemiologia , COVID-19/terapia , Masculino , Feminino , Idoso de 80 Anos ou mais , Hong Kong/epidemiologia , Hospitalização/estatística & dados numéricos
7.
Reprod Biol Endocrinol ; 11: 13, 2013 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-23442365

RESUMO

BACKGROUND: The present study demonstrates the expression of intermedin (IMD) and its receptor components in the uterus of the female rat during the estrous cycle and its effect on uterine contraction. METHODS: The gene expression level of intermedin and its receptor components and the peptide level of intermedin were studied by real-time RT-PCR and enzyme immunoassay (EIA) respectively. The separation of precursor and mature IMD was studied by gel filtration chromatography and EIA. The localization of IMD in the uterus was investigated by immunohistochemistry. The effect of IMD on in vitro uterine contraction was studied by organ bath technique. RESULTS: Uterine mRNAs of Imd and its receptor components and IMD levels displayed cyclic changes across the estrous cycle. Imd mRNA level was the highest at proestrus while the IMD level was the highest at diestrus. IMD was found in the luminal and glandular epithelia and IMD treatment significantly reduced the amplitude and frequency of uterine contraction but not the basal tone. Both calcitonin gene-related peptide (CGRP) receptor antagonist hCGRP8-37 and adrenomedullin (ADM) receptor antagonist hADM22-52 partially abolished the inhibitory effect of IMD on uterine contraction while the specific IMD receptor antagonist hIMD17-47 completely blocked the actions. The enzyme inhibitors of NO (L-NAME) and PI3K (Wortmannin) pathways diminished the IMD effects on uterine contraction while the cAMP/PKA blocker, KT5720, had no effect, indicating an involvement of NO and PI3K/Akt but not PKA. CONCLUSIONS: IMD and the gene expression of its receptor components are differentially regulated in the uterus during the estrous cycle and IMD inhibits uterine contraction by decreasing the amplitude and frequency.


Assuntos
Adrenomedulina/genética , Ciclo Estral/metabolismo , Regulação da Expressão Gênica , Neuropeptídeos/fisiologia , Contração Uterina/metabolismo , Adrenomedulina/biossíntese , Adrenomedulina/fisiologia , Animais , Ciclo Estral/genética , Feminino , Neuropeptídeos/biossíntese , Neuropeptídeos/genética , Técnicas de Cultura de Órgãos , Ratos , Ratos Sprague-Dawley , Contração Uterina/genética
8.
Sci Rep ; 13(1): 6763, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37185447

RESUMO

PTEN hamartoma tumour syndrome is characterised by mutations in the human PTEN gene. We performed transcriptomic and proteomic analyses of neural tissues and primary cultures from heterozygous and homozygous Pten-knockout mice. The somatosensory cortex of heterozygous Pten-knockout mice was enriched in immune response and oligodendrocyte development Gene Ontology (GO) terms. Parallel proteomic analysis revealed differentially expressed proteins (DEPs) related to dendritic spine development, keratinisation and hamartoma signatures. However, primary astrocytes (ASTs) from heterozygous Pten-knockout mice were enriched in the extracellular matrix GO term, while primary cortical neurons (PCNs) were enriched in immediate-early genes. In ASTs from homozygous Pten-knockout mice, cilium-related activity was enriched, while PCNs exhibited downregulation of forebrain neuron generation and differentiation, implying an altered excitatory/inhibitory balance. By integrating DEPs with pre-filtered differentially expressed genes, we identified the enrichment of traits of intelligence, cognitive function and schizophrenia, while DEPs in ASTs were significantly associated with intelligence and depression.


Assuntos
Proteômica , Transcriptoma , Animais , Camundongos , Perfilação da Expressão Gênica , Camundongos Knockout , Neurônios/metabolismo , PTEN Fosfo-Hidrolase/metabolismo
9.
Biochim Biophys Acta ; 1813(6): 1239-44, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21458501

RESUMO

Growth factor activates mitogen-activated protein kinase kinases to promote cell growth. Mitochondrial biogenesis is an integral part of cell growth. How growth factor regulates mitochondrial biogenesis is not fully understood. In this study, we found that mitochondrial mass was specifically reduced upon serum starvation and induced upon re-feeding with serum. Using mitogen-activated protein kinase kinases inhibitor U0126, we found that the mRNA expression levels of ATP synthase, cytochrome-C, mitochondrial transcription factor A, and mitofusin 2 were reduced. Since the transcriptional levels of these genes are under the control of peroxisome proliferator-activated receptor γ coactivator-1α and -1ß (PGC-1α and PGC-1ß), we examined and found that only the mRNA and protein levels of PGC-1ß were suppressed. Importantly, over-expression of PGC-1ß partially reversed the reduction of mitochondrial mass upon U0126 treatment. Thus, we conclude that mitogen-activated protein kinase kinases direct mitochondrial biogenesis through selectively inducing PGC-1ß expression.


Assuntos
Proteínas de Transporte/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Western Blotting , Butadienos/farmacologia , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Citocromos c/genética , Citocromos c/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , GTP Fosfo-Hidrolases , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mitocôndrias/genética , Proteínas Mitocondriais/genética , ATPases Mitocondriais Próton-Translocadoras/genética , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Nitrilas/farmacologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Proteínas de Ligação a RNA , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transfecção , Receptor ERRalfa Relacionado ao Estrogênio
10.
Hepatology ; 53(2): 458-66, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21274867

RESUMO

UNLABELLED: Hepatocyte nuclear factor-4 alpha (HNF-4α) is an important transcription factor governing the expression of genes involved in multiple metabolic pathways. Secreted phospholipase A(2) GXIIB (PLA(2) GXIIB) is an atypical member of a class of secreted phospholipases A(2) . We establish in this study that PLA(2) GXIIB is an HNF-4α target gene. We demonstrate that HNF-4α binds to a response element on the PLA(2) GXIIB promoter. Moreover, HNF-4α agonists induce PLA(2) GXIIB expression in human hepatocarcinoma cells. Importantly, PLA(2) GXIIB-null mice accumulate triglyceride, cholesterol, and fatty acids in the liver and develop severe hepatosteatosis resembling some of the phenotypes of liver-specific HNF-4α-null mice. These defects are in part due to compromised hepatic very low-density lipoprotein secretion. Finally, adenovirus-mediated overexpression of HNF-4α elevates serum triglyceride level in wild-type but not PLA(2) GXIIB-null mice. CONCLUSION: Collectively, these evidences suggest that HNF-4α is a key physiological PLA(2) GXIIB transcriptional regulator and that PLA(2) GXIIB is a novel mediator of triglyceride metabolism in the liver.


Assuntos
Fator 4 Nuclear de Hepatócito/metabolismo , Fígado/metabolismo , Fosfolipases A2 Secretórias/metabolismo , Triglicerídeos/metabolismo , Animais , Colesterol/metabolismo , Modelos Animais de Doenças , Ácidos Graxos/metabolismo , Fígado Gorduroso/metabolismo , Fator 4 Nuclear de Hepatócito/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
11.
Cancer Lett ; 549: 215914, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36116740

RESUMO

Weighted gene co-expression network analysis (WGCNA) identified a cell-cycle module that is associated with poor prognosis and aggressiveness of glioma. One of the core members, Regulator of chromatin condensation 2 (RCC2) is a component of the chromosome passenger complex. Accumulating evidence suggests that RCC2 plays a vital role in the mitotic process and that abnormal RCC2 expression is involved in cancer development. Gene silencing experiments show that RCC2 is required for glioma cell proliferation and migration. RNA-Sequencing analysis reveals a dual role of RCC2 in both the cell cycle and metabolism. Specifically, RCC2 regulates G2/M progression via CDC2 phosphorylation at Tyrosine 15. Metabolomic analysis identifies a role for RCC2 in promoting the glycolysis and pentose phosphate pathway. RCC2 exerts effects on metabolism by stabilizing the transcription factor BACH1 at its C-terminus leading to the transcriptional upregulation of hexokinase 2 (HK2). These findings elucidate a novel PTEN/RCC2/BACH1/HK2 signaling axis that drives glioma progression through the dual regulation of mitotic cell cycle and glycolytic events.


Assuntos
Glioma , Hexoquinase , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Cromatina , Proteínas Cromossômicas não Histona , Cromossomos/metabolismo , Glioma/genética , Glucose , Glicólise , Fatores de Troca do Nucleotídeo Guanina , Hexoquinase/genética , Humanos , RNA/metabolismo , Fatores de Transcrição/genética , Tirosina/metabolismo , Regulação para Cima
12.
Nat Commun ; 13(1): 6747, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36347848

RESUMO

Single cell approaches have increased our knowledge about the cell type composition of the non-human primate (NHP), but a detailed characterization of area-specific regulatory features remains outstanding. We generated single-cell transcriptomic and chromatin accessibility (single-cell ATAC) data of 358,237 cells from prefrontal cortex (PFC), primary motor cortex (M1) and primary visual cortex (V1) of adult female cynomolgus monkey brain, and integrated this dataset with Stereo-seq (spatial enhanced resolution omics-sequencing) of the corresponding cortical areas to assign topographic information to molecular states. We identified area-specific chromatin accessible sites and their targeted genes, including the cell type-specific transcriptional regulatory network associated with excitatory neurons heterogeneity. We reveal calcium ion transport and axon guidance genes related to specialized functions of PFC and M1, identified the similarities and differences between adult macaque and human oligodendrocyte trajectories, and mapped the genetic variants and gene perturbations of human diseases to NHP cortical cells. This resource establishes a transcriptomic and chromatin accessibility combinatory regulatory landscape at a single-cell and spatially resolved resolution in NHP cortex.


Assuntos
Neurônios , Córtex Pré-Frontal , Animais , Feminino , Macaca fascicularis/genética , Neurônios/metabolismo , Córtex Pré-Frontal/metabolismo , Redes Reguladoras de Genes , Cromatina/genética , Cromatina/metabolismo
13.
Int J Cancer ; 129(10): 2527-31, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21213215

RESUMO

MicroRNAs (miRNAs) are noncoding RNAs that regulate gene expression by inhibiting translation or by promoting mRNA degradation. Previously, we established that microRNA-153 (miR-153) induces apoptosis by downregulating B-cell lymphoma 2 (Bcl-2) and myeloid cell leukemia sequence 1 (Mcl-1) protein expression levels in glioblastoma cell line DBTRG-05MG. In our study, we show that ectopic expression of miR-153 also inhibits the protein kinase B (PKB/Akt) pathway via reducing the protein level of insulin receptor substrate-2 (Irs-2). Moreover, simultaneous treatment with the chromatin-modifying drugs 4-phenylbutyric acid and 5-aza-2'-deoxycytidine induces miR-153 expression to suppress Irs-2, Bcl-2 and Mcl-1 expressions, thus downregulating the survival but upregulating the apoptotic pathways, implying that tumor suppressor miR-153 is a dual life and death regulator.


Assuntos
Glioblastoma/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , MicroRNAs/metabolismo , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Linhagem Celular Tumoral , Cromatina/efeitos dos fármacos , Decitabina , Humanos , Fenilbutiratos/farmacologia
14.
Front Pharmacol ; 12: 784231, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34880765

RESUMO

The prevalence of diabetes mellitus has been increasing for decades worldwide. To develop safe and potent therapeutics, animal models contribute a lot to the studies of the mechanisms underlying its pathogenesis. Dietary induction using is a well-accepted protocol in generating insulin resistance and diabetes models. In the present study, we reported the multi-omics profiling of the liver and sera from both peripheral blood and hepatic portal vein blood from Macaca fascicularis that spontaneously developed Type-2 diabetes mellitus with a chow diet (sDM). The other two groups of the monkeys fed with chow diet and high-fat high-sugar (HFHS) diet, respectively, were included for comparison. Analyses of various omics datasets revealed the alterations of high consistency. Between the sDM and HFHS monkeys, both the similar and unique alterations in the lipid metabolism have been demonstrated from metabolomic, transcriptomic, and proteomic data repeatedly. The comparison of the proteome and transcriptome confirmed the involvement of fatty acid binding protein 4 (FABP4) in the diet-induced pathogenesis of diabetes in macaques. Furthermore, the commonly changed genes between spontaneous diabetes and HFHS diet-induced prediabetes suggested that the alterations in the intra- and extracellular structural proteins and cell migration in the liver might mediate the HFHS diet induction of diabetes mellitus.

15.
Br J Pharmacol ; 178(21): 4352-4367, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34233019

RESUMO

BACKGROUND AND PURPOSE: Metabolic adaptation driven by oestrogen-related receptor-α (ERRα/NR3B1) is required to meet the increased energy demand during osteoclast differentiation. Here, we hypothesize that natural product, andrographolide, acts as an ERRα inverse agonist to inhibit osteoclastogenesis. EXPERIMENTAL APPROACH: Virtual docking and site-directed mutagenesis analysis were employed to study the binding mode of andrographolide to ERRα. Co-immunoprecipitation, luciferase reporter assay, real-time polymerase chain reaction (PCR) and immunoblot analyses were performed to identify andrographolide as an ERRα inverse agonist. The pharmacological effects of andrographolide in vivo were assessed in mice models of osteopenia induced by either a high-fat diet in male or ovariectomy in female mice. KEY RESULTS: ERRα-dependent expression of glutaminase, a rate-limiting enzyme of mitochondrial glutamine anaplerosis, is required for ex vivo bone marrow osteoclast differentiation. Andrographolide inhibited glutaminase expression induced by ERRα and co-activator peroxisome proliferator-activated receptor γ co-activator-1ß (PGC-1ß), leading to reduction in osteoclastogenesis. Andrographolide acted as an inverse agonist of ERRα by disrupting its interaction with co-activator PGC-1ß. Phenylalanine 232, valine 395 and phenylalanine 399 of ERRα ligand-binding domain were confirmed to be essential for this effect. In contrast, glutaminase overexpression restored the impairment triggered by andrographolide. Accordingly, andrographolide suppressed osteoclastic bone resorption and attenuated bone loss in vivo. CONCLUSIONS AND IMPLICATIONS: These findings demonstrate that andrographolide acts as an ERRα inverse agonist for perturbation of ERRα/PGC-1ß/glutaminase axis-driven metabolic adaption during osteoclast differentiation, implying that andrographolide may be a promising natural compound for preventing physiological and pathological bone loss.


Assuntos
Doenças Ósseas Metabólicas , Osteogênese , Animais , Diterpenos , Estrogênios , Feminino , Masculino , Camundongos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Receptores de Estrogênio/metabolismo , Fatores de Transcrição/metabolismo , Receptor ERRalfa Relacionado ao Estrogênio
16.
Mol Cell Endocrinol ; 513: 110867, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32422400

RESUMO

Hepatic nuclear factor 4 alpha (HNF4α) drives the expression of apolipoprotein B (ApoB), microsomal triglyceride transfer protein (MTP) and phospholipase A2 G12B (PLA2G12B), governing hepatic very-low-density lipoprotein (VLDL) production and secretion. Andrographolide (AP) is a major constituent isolated from Andrographis paniculata. We found that AP can disrupt the interaction between HNF4α and its coactivator peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α). Virtual docking and mutational analysis indicated that arginine 235 of HNF4α is essential for binding to AP. As a consequence of antagonizing the activity of HNF4α, AP suppresses the expression of ApoB, MTP and PLA2G12B and reduces the rate of hepatic VLDL secretion in vivo. AP additionally reduced gluconeogenesis via down-regulating the expression of HNF4α target genes phosphoenolpyruvate carboxykinase (Pepck) and glucose-6-phosphatase (G6pc). Collectively, our results suggest that AP affects liver function via modulating the transcriptional activity of HNF4α.


Assuntos
Diterpenos/farmacologia , Fator 4 Nuclear de Hepatócito/antagonistas & inibidores , Fígado/efeitos dos fármacos , Animais , Células Cultivadas , Gluconeogênese/efeitos dos fármacos , Gluconeogênese/genética , Células HEK293 , Células Hep G2 , Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/antagonistas & inibidores , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Ligação Proteica/efeitos dos fármacos
17.
Theranostics ; 10(24): 10874-10891, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042259

RESUMO

Rationale: Men and postmenopausal women are more prone to developing non-alcoholic fatty liver disease/steatohepatitis (NAFLD/NASH) than premenopausal women. However, the pathological links and underlying mechanisms of this disparity are still elusive. The sex-difference in hepatic very low-density lipoprotein (VLDL) assembly and secretion may contribute to NAFLD development. Estrogen-related receptor alpha (ERRα) is a key regulator of several metabolic processes. We hypothesized that ERRα plays a role contributing to the sex-difference in hepatic VLDL assembly and secretion. Methods: VLDL secretion and essential genes governing said process were assessed in male and female mice. Liver-specific ERRα-deficient (ERRαLKO) mice were generated to assess the rate of hepatic VLDL secretion and alteration in target gene expression. Overexpression of either microsomal triglyceride transfer protein (Mttp) or phospholipase A2 G12B (Pla2g12b) by adenovirus was performed to test if the fatty liver phenotype in male ERRαLKO mice was due to defects in hepatic VLDL secretion. Female ERRαLKO mice were put on a diet high in saturated fat, fructose and cholesterol (HFHC) to promote NASH development. Wild type female mice were either ovariectomized or treated with tamoxifen to induce a state of estrogen deficiency or disruption in estrogen signaling. Adenovirus was used to overexpress ERRα in these mice to test if ERRα was sufficient to rescue the suppressed VLDL secretion due to estrogen dysfunction. Finally, wild type male mice on a high-fat diet (HFD) were treated with an ERRα inverse agonist to assess if suppressing ERRα activity pharmacologically would lead to fatty liver development. Results: ERRα is an indispensable mediator modulating hepatic triglyceride-rich very low-density lipoprotein (VLDL-TG) assembly and secretion through coordinately controlling target genes apolipoprotein B (Apob), Mttp and Pla2g12b in a sex-different manner. Hepatic VLDL-TG secretion is blunted in ERRαLKO mice, leading to hepatosteatosis which exacerbates endoplasmic reticulum stress and inflammation paving ways for NASH development. Importantly, ERRα acts downstream of estrogen/ERα signaling in contributing to the sex-difference in hepatic VLDL secretion effecting hepatic lipid homeostasis. Conclusions: Our results highlight ERRα as a key mediator which contributes to the sex disparity in NAFLD development, suggesting that selectively restoring ERRα activity in the liver may be a novel strategy for treating NAFLD/NASH.


Assuntos
Disparidades nos Níveis de Saúde , Lipoproteínas VLDL/metabolismo , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptores de Estrogênio/metabolismo , Triglicerídeos/metabolismo , Animais , Apolipoproteínas B/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Feminino , Fosfolipases A2 do Grupo X/genética , Fosfolipases A2 do Grupo X/metabolismo , Células HEK293 , Células Hep G2 , Hepatócitos , Humanos , Masculino , Camundongos , Camundongos Knockout , Nitrilas/farmacologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Cultura Primária de Células , Receptores de Estrogênio/antagonistas & inibidores , Receptores de Estrogênio/genética , Fatores Sexuais , Tiazóis/farmacologia , Receptor ERRalfa Relacionado ao Estrogênio
18.
FEBS J ; 287(22): 4848-4861, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32150788

RESUMO

Germline mutation in the PTEN gene is the genetic basis of PTEN hamartoma tumor syndrome with the affected individuals harboring features of autism spectrum disorders. Characterizing a panel of 14 autism-associated PTEN missense mutations revealed reduced protein stability, catalytic activity, and subcellular distribution. Nine out of 14 (64%) PTEN missense mutants had reduced protein expression with most mutations confined to the C2 domain. Selected mutants displayed enhanced polyubiquitination and shortened protein half-life, but that did not appear to involve the polyubiquitination sites at lysine residues at codon 13 or 289. Analyzing their intrinsic lipid phosphatase activities revealed that 78% (11 out of 14) of these mutants had twofold to 10-fold reduction in catalytic activity toward phosphatidylinositol phosphate substrates. Analyzing the subcellular localization of the PTEN missense mutants showed that 64% (nine out of 14) had altered nuclear-to-cytosol ratios with four mutants (G44D, H123Q, E157G, and D326N) showing greater nuclear localization. The E157G mutant was knocked-in to an induced pluripotent stem cell line and recapitulated a similar nuclear targeting preference. Furthermore, iPSCs expressing the E157G mutant were more proliferative at the neural progenitor cell stage but exhibited more extensive dendritic outgrowth. In summary, the combination of biological changes in PTEN is expected to contribute to the behavioral and cellular features of this neurodevelopmental disorder.


Assuntos
Transtorno do Espectro Autista/genética , Núcleo Celular/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Mutação de Sentido Incorreto , Crescimento Neuronal/genética , PTEN Fosfo-Hidrolase/genética , Transtorno do Espectro Autista/metabolismo , Western Blotting , Linhagem Celular Tumoral , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células PC-3 , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidato Fosfatase/genética , Fosfatidato Fosfatase/metabolismo , Fosforilação , Estabilidade Proteica
19.
Clin Cancer Res ; 14(9): 2560-9, 2008 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-18451217

RESUMO

PURPOSE: Early events in colorectal tumorigenesis include mutation of the adenomatous polyposis coli (APC) gene and epigenetic hypermethylation with transcriptional silencing of the O(6)-methylguanine DNA methyltransferase (MGMT), human mut L homologue 1 (hMLH1), and P16/CDKN2A genes. Epigenetic alterations affect genetic events: Loss of MGMT via hypermethylation reportedly predisposes to guanine-to-adenine or cytosine-to-thymine (G:C-->A:T) transition mutations in KRAS and P53, and silencing of hMLH1 leads to high levels of microsatellite instability (MSI-H)/mutator phenotype, suggesting that epigenetic-genetic subtypes exist. EXPERIMENTAL DESIGN: We evaluated the relationships of aberrant methylation of APC, MGMT, hMLH1, P16, N33, and five MINTs to mutations in APC, KRAS, BRAF, and P53 in 208 colorectal carcinomas. RESULTS: We found that APC hypermethylation was age related (P = 0.04), in contrast to the other genes, and did not cluster with CpG island methylator phenotype (CIMP) markers. Hypermethylation of APC concurrently with either MGMT or hMLH1 was strongly associated with occurrence of G-to-A transitions in APC [odds ratio (OR), 26.8; P < 0.0002 from multivariable logic regression model], but C-to-T transitions had no associations. There was no relationship of hypermethylation of any gene, including MGMT, with G-to-A or C-to-T transitions in KRAS or P53, although APC hypermethylation was associated with P53 mutation (P < 0.0002). CIMP with MSI-H due to hMLH1 hypermethylation, or CIMP with loss of MGMT expression in non-MSI-H tumors, was associated with BRAF mutation (OR, 4.5; P < 0.0002). CIMP was also associated with BRAF V600E T-to-A transversion (OR, 48.5; P < 0.0002). CONCLUSIONS: Our findings suggest that the heterogeneous epigenetic dysregulation of promoter methylation in various genes is interrelated with the occurrence of mutations, as manifested in epigenetic-genetic subgroups of tumors.


Assuntos
Neoplasias Colorretais/genética , Ilhas de CpG/genética , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Epigênese Genética , Genes APC , Proteínas Supressoras de Tumor/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias Colorretais/metabolismo , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Feminino , Genes p53 , Genes ras , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Proteínas Supressoras de Tumor/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteínas ras/genética , Proteínas ras/metabolismo
20.
Contemp Clin Trials ; 78: 101-106, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30625372

RESUMO

BACKGROUND: Currently, there is a lack of data on effective lifestyle recommendations for normal-weight diabetics (NWD), who can represent up to 1 in 5 individuals with Type II Diabetes Mellitus (T2DM). NWD is especially prevalent in Asian populations and the elderly. Specific exercise treatment recommendations are needed for patients with normal-weight diabetes (NWD), as those in this category face higher mortality rates than overweight and obese diabetics. Standard T2DM treatment recommends aerobic training; however, performing aerobic training alone may not be appropriate for NWD and strength training may be a more effective treatment recommendation. OBJECTIVE: While it is known that strength and aerobic training are beneficial in obese diabetics, there is currently insufficient evidence to recommend this regimen in NWD. The Strength Training Regimen for Normal Weight Diabetics (STRONG-D) study aims to determine the best exercise regimen for NWD and address the current lack of appropriate physical activity recommendations for this population. The primary goal of this study is to determine whether strength training aids glycemic control better than aerobic training in NWD. STUDY DESIGN: STRONG-D is a three-arm randomized controlled trial designed to compare the clinical effectiveness of structured strength training only, aerobic training only, and combination (strength + aerobic) training sessions, modeled after the intervention in the Health Benefits of Aerobic and Resistance Training in T2DM patients (HART-D) study. Potential participants meeting eligibility criteria of HbA1c values of 6.5% to 13.0% and BMI of 18.5 kg/m2 to 25 kg/m2 will be enrolled. After randomization, participants will begin a 9-month exercise intervention. The primary outcomes will be HbA1c levels. The secondary endpoints will include physical fitness, body composition measured by Dual X-Ray Absorptiometry (DXA) scans, and leg strength and endurance measured by Biodex testing. Initial follow-up visits will occur at 3 months, 6 months, and 9 months. To determine the long-term effects of the exercise intervention, passive follow-up will continue via electronic health records (EHR) until a 24-month follow-up visit. A total of 282 participants will be randomized into the three study arms determine the clinically significant differences between strength-only, aerobic-only and combination regimens.


Assuntos
Composição Corporal/fisiologia , Diabetes Mellitus Tipo 2/terapia , Terapia por Exercício/métodos , Hemoglobinas Glicadas/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pesos e Medidas Corporais , Diabetes Mellitus Tipo 2/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aptidão Física , Projetos de Pesquisa , Treinamento Resistido , Método Simples-Cego , Adulto Jovem
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