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1.
Nutrition ; 118: 112295, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38103266

RESUMO

OBJECTIVES: The aim of this study was to assess the association of genetically determined iron status with the risk for non-alcoholic fatty liver disease (NAFLD) using two-sample Mendelian randomization (MR) analysis. METHODS: We applied single nucleotide polymorphisms (SNPs) associated at genome-wide significance with iron status proxied by serum iron, ferritin, transferrin, and transferrin saturation from the Genetics of Iron status Consortium (N = 48 793), in a genome-wide association study of 1664 NAFLD cases and 400 055 controls from the United Kingdom Biobank. A SNP associated with multiple markers of iron status was only applied to one marker with the strongest association in the main analysis. Their effects on NAFLD were calculated using inverse variance weighting after excluding SNPs associated with alkaline phosphatase and lipid metabolism. RESULTS: The risk for NAFLD is negatively associated with genetically predicted serum transferrin level with a 20% reduction in NAFLD risk per SD (0.65g/L) increase in transferrin (95% confidence interval [CI], 0.66-0.97), and trending positive association with transferrin saturation (odds ratio [OR], 1.50; 95% CI, 0.96-2.35) but it was not associated with serum iron (OR, 0.90; 95% CI, 0.63-1.29) and ferritin (OR, 1.33; 95% CI, 0.54-3.30). CONCLUSIONS: MR analysis provided evidence that genetically predicted higher serum transferrin, indicating lower iron status, may be protective against NAFLD, whereas higher transferrin saturation, indicating higher iron status, might increase the risk for NAFLD and its pathogenesis.


Assuntos
Ferro , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/genética , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Ferritinas , Transferrina , Polimorfismo de Nucleotídeo Único
2.
Front Endocrinol (Lausanne) ; 14: 1283907, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38033998

RESUMO

Objective: Congenital hyperinsulinism (CHI) is a group of clinically and genetically heterogeneous disorders characterized by dysregulated insulin secretion. The aim of the study was to elucidate genetic etiologies of Taiwanese children with the most severe diazoxide-unresponsive CHI and analyze their genotype-phenotype correlations. Methods: We combined Sanger with whole exome sequencing (WES) to analyze CHI-related genes. The allele frequency of the most common variant was estimated by single-nucleotide polymorphism haplotype analysis. The functional effects of the ATP-sensitive potassium (KATP) channel variants were assessed using patch clamp recording and Western blot. Results: Nine of 13 (69%) patients with ten different pathogenic variants (7 in ABCC8, 2 in KCNJ11 and 1 in GCK) were identified by the combined sequencing. The variant ABCC8 p.T1042QfsX75 identified in three probands was located in a specific haplotype. Functional study revealed the human SUR1 (hSUR1)-L366F KATP channels failed to respond to intracellular MgADP and diazoxide while hSUR1-R797Q and hSUR1-R1393C KATP channels were defective in trafficking. One patient had a de novo dominant mutation in the GCK gene (p.I211F), and WES revealed mosaicism of this variant from another patient. Conclusion: Pathogenic variants in KATP channels are the most common underlying cause of diazoxide-unresponsive CHI in the Taiwanese cohort. The p.T1042QfsX75 variant in the ABCC8 gene is highly suggestive of a founder effect. The I211F mutation in the GCK gene and three rare SUR1 variants associated with defective gating (p.L366F) or traffic (p.R797Q and p.R1393C) KATP channels are also associated with the diazoxide-unresponsive phenotype.


Assuntos
Hiperinsulinismo Congênito , Canais de Potássio Corretores do Fluxo de Internalização , Humanos , Criança , Diazóxido/uso terapêutico , Canais de Potássio Corretores do Fluxo de Internalização/genética , Receptores de Sulfonilureias/genética , Hiperinsulinismo Congênito/tratamento farmacológico , Hiperinsulinismo Congênito/genética , Estudos de Associação Genética , Trifosfato de Adenosina
3.
J Gen Virol ; 104(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37043371

RESUMO

Chikungunya virus (CHIKV) is a re-emerging mosquito-borne virus, which causes epidemics of fever, joint pain and rash. There are three genotypes: West African, East/Central/South/Africa (ECSA) and Asian, with the latter two predominant globally. Genotype-specific differences in clinical presentations, virulence and immunopathology have been described. Macrophages are key cells in immune responses against CHIKV. Circulating blood monocytes enter tissue to differentiate into monocyte-derived macrophages (MDMs) in response to CHIKV infection at key replication sites such as lymphoid organs and joints. This study analyses differences in replication and induced immune mediators following infection of MDMs with Asian and ECSA CHIKV genotypes. Primary human MDMs were derived from residual blood donations. Replication of Asian (MY/06/37348) or ECSA (MY/08/065) genotype strains of CHIKV in MDMs was measured by plaque assay. Nineteen immune mediators were measured in infected cell supernatants using multiplexed immunoassay or ELISA. MY/08/065 showed significantly higher viral replication at 24 h post-infection (h p.i.) but induced significantly lower expression of proinflammatory cytokines (CCL-2, CCL-3, CCL-4, RANTES and CXCL-10) and the anti-inflammatory IL-1Ra compared to MY/06/37348. No differences were seen at later time points up to 72 h p.i. During early infection, MY/08/065 induced lower proinflammatory immune responses in MDMs. In vivo, this may lead to poorer initial control of viral infection, facilitating CHIKV replication and dissemination to other sites such as joints. This may explain the consistent past findings that the ECSA genotype is associated with greater viremia and severity of symptoms than the Asian genotype. Knowledge of CHIKV genotype-specific immunopathogenic mechanisms in human MDMs is important in understanding of clinical epidemiology, biomarkers and therapeutics in areas with co-circulation of different genotypes.


Assuntos
Febre de Chikungunya , Vírus Chikungunya , Animais , Humanos , Vírus Chikungunya/genética , Imunidade Inata , Macrófagos , Replicação Viral , Genótipo
4.
J Clin Invest ; 133(9)2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36927960

RESUMO

During the development of heart failure (HF), the capacity for cardiomyocyte (CM) fatty acid oxidation (FAO) and ATP production is progressively diminished, contributing to pathologic cardiac hypertrophy and contractile dysfunction. Receptor-interacting protein 140 (RIP140, encoded by Nrip1) has been shown to function as a transcriptional corepressor of oxidative metabolism. We found that mice with striated muscle deficiency of RIP140 (strNrip1-/-) exhibited increased expression of a broad array of genes involved in mitochondrial energy metabolism and contractile function in heart and skeletal muscle. strNrip1-/- mice were resistant to the development of pressure overload-induced cardiac hypertrophy, and CM-specific RIP140-deficient (csNrip1-/-) mice were protected against the development of HF caused by pressure overload combined with myocardial infarction. Genomic enhancers activated by RIP140 deficiency in CMs were enriched in binding motifs for transcriptional regulators of mitochondrial function (estrogen-related receptor) and cardiac contractile proteins (myocyte enhancer factor 2). Consistent with a role in the control of cardiac fatty acid oxidation, loss of RIP140 in heart resulted in augmented triacylglyceride turnover and fatty acid utilization. We conclude that RIP140 functions as a suppressor of a transcriptional regulatory network that controls cardiac fuel metabolism and contractile function, representing a potential therapeutic target for the treatment of HF.


Assuntos
Insuficiência Cardíaca , Proteína 1 de Interação com Receptor Nuclear , Animais , Camundongos , Cardiomegalia/metabolismo , Metabolismo Energético/genética , Ácidos Graxos/metabolismo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Miócitos Cardíacos/metabolismo , Proteína 1 de Interação com Receptor Nuclear/genética , Proteína 1 de Interação com Receptor Nuclear/metabolismo
5.
Chemosphere ; 313: 137507, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36495975

RESUMO

Increasing use of phosphorus products and excessive exploitation of phosphorus resources become two major problems in perspective of phosphorus sustainable development. Phosphorus recovery is the shortcut to solve this dilemma. Combining electrochemistry, an iron-air fuel cell was adopted to recover phosphate and electricity from phosphate-containing wastewater in our previous studies. The present study focused on investigating the effects of catholyte/anolyte conductivity, external resistance, and anolyte pH on the performance of iron-air fuel cell, and obtaining the optimized conditions. Furthermore, the electrochemical methods of phosphate recovery were compared and assessed, and it is concluded that iron-air fuel cell has great potential for energy recovery. The phosphate removal efficiencies and vivianite yield roughly positively correlated with the catholyte conductivity and the anolyte pH, but negatively correlated with the external resistance and the anolyte conductivity. The electricity generation roughly positively correlated with the catholyte conductivity and anolyte conductivity, but showed limitations in the test range of anolyte pH and external resistance. To pursue high phosphate removal efficiencies and vivianite yield, the catholyte conductivity, external resistance, anolyte pH and anolyte conductivity were suggested to be 35 g-NaCl/L, 10 Ω, 8 and 0 g-NaCl/L. While if electricity generation was the primary goal, these parameters should be 35 g-NaCl/L, 220 Ω, 5 and 70 g-NaCl/L. The optimized conditions will help to improve the phosphate removal efficiency, vivianite yield and electricity generation, and to promote the development of iron-air fuel cell technology.


Assuntos
Fontes de Energia Bioelétrica , Águas Residuárias , Ferro , Cloreto de Sódio , Desenvolvimento Sustentável , Eletricidade , Fosfatos , Fósforo , Eletrodos
6.
Histopathology ; 82(1): 198-210, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36482271

RESUMO

This is a review on the use of artificial intelligence for digital breast pathology. A systematic search on PubMed was conducted, identifying 17,324 research papers related to breast cancer pathology. Following a semimanual screening, 664 papers were retrieved and pursued. The papers are grouped into six major tasks performed by pathologists-namely, molecular and hormonal analysis, grading, mitotic figure counting, ki-67 indexing, tumour-infiltrating lymphocyte assessment, and lymph node metastases identification. Under each task, open-source datasets for research to build artificial intelligence (AI) tools are also listed. Many AI tools showed promise and demonstrated feasibility in the automation of routine pathology investigations. We expect continued growth of AI in this field as new algorithms mature.


Assuntos
Inteligência Artificial , Neoplasias da Mama , Humanos , Feminino
7.
Transfus Med ; 32(6): 484-491, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36239101

RESUMO

OBJECTIVES: To evaluate the performance and utility of a time-temperature indicator (TTI) to determine the cumulative exposure time (CET) of red cell components (RCC) to temperatures above 10°C occurring within and outside the transfusion laboratory. BACKGROUND AND OBJECTIVES: Blood centres often use the '30 or 60-min rule' for accepting RCC exposed to room temperature (RT) back into inventory. Effective monitoring of these temperature deviations is however lacking. MATERIALS AND METHODS: A Timestrip PLUS® TP153 10°C (TS + 10) TTI was attached to RCC units after preparation of the unit in the blood bank or on issue to the ward, to track the CET > 10°C during laboratory processing and outside the transfusion laboratory. RESULTS: The mean CET of 153 RCC tracked within the laboratory was 56 min. Sixty-four (41.8%) and 34 (22.2%) of RCC had core temperature (CT) >10°C for more than 30 and 60 min, respectively. Among the 69 RCC that were returned unused, 27 (39.1%), 17 (24.6%) and 5 (7.2%) RCC units had CT >10°C for more than 30, 60 and 120 min respectively. CONCLUSION: A large proportion of RCC have CT >10°C exceeding 30 min during handling within the transfusion laboratory, as well as when RCC are returned unused from transfusion locations. Corrective measures should be implemented to better manage the cold chain to avoid undesirable consequences to blood transfusion. A temperature sensitive device that can also indicate CET can be employed to objectively monitor the period that RCC remained at a CT that exceeds 10°C.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Temperatura , Preservação de Sangue , Eritrócitos
8.
JCI Insight ; 7(18)2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-36134662

RESUMO

Therapy with radiation plus cisplatin kills HPV+ oropharyngeal squamous cell carcinomas (OPSCCs) by increasing reactive oxygen species beyond cellular antioxidant capacity. To explore why these standard treatments fail for some patients, we evaluated whether the variation in HPV oncoprotein levels among HPV+ OPSCCs affects mitochondrial metabolism, a source of antioxidant capacity. In cell line and patient-derived xenograft models, levels of HPV full-length E6 (fl-E6) inversely correlated with oxidative phosphorylation, antioxidant capacity, and therapy resistance, and fl-E6 was the only HPV oncoprotein to display such correlations. Ectopically expressing fl-E6 in models with low baseline levels reduced mitochondrial mass, depleted antioxidant capacity, and sensitized to therapy. In this setting, fl-E6 repressed the peroxisome proliferator-activated receptor gamma co-activator 1α/estrogen-related receptor α (PGC-1α/ERRα) pathway for mitochondrial biogenesis by reducing p53-dependent PGC-1α transcription. Concordant observations were made in 3 clinical cohorts, where expression of mitochondrial components was higher in tumors of patients with reduced survival. These tumors contained the lowest fl-E6 levels, the highest p53 target gene expression, and an activated PGC-1α/ERRα pathway. Our findings demonstrate that E6 can potentiate treatment responses by depleting mitochondrial antioxidant capacity and provide evidence for low E6 negatively affecting patient survival. E6's interaction with the PGC-1α/ERRα axis has implications for predicting and targeting treatment resistance in OPSCC.


Assuntos
Neoplasias Orofaríngeas , Infecções por Papillomavirus , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Antioxidantes/metabolismo , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Humanos , Neoplasias Orofaríngeas/terapia , PPAR gama/metabolismo , Infecções por Papillomavirus/complicações , Espécies Reativas de Oxigênio/metabolismo , Receptores de Estrogênio , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53 , Receptor ERRalfa Relacionado ao Estrogênio
9.
Nat Commun ; 13(1): 1991, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35418170

RESUMO

Estrogen-related receptors (ERR) α and γ were shown recently to serve as regulators of cardiac maturation, yet the underlying mechanisms have not been delineated. Herein, we find that ERR signaling is necessary for induction of genes involved in mitochondrial and cardiac-specific contractile processes during human induced pluripotent stem cell-derived cardiomyocyte (hiPSC-CM) differentiation. Genomic interrogation studies demonstrate that ERRγ occupies many cardiomyocyte enhancers/super-enhancers, often co-localizing with the cardiogenic factor GATA4. ERRγ interacts with GATA4 to cooperatively activate transcription of targets involved in cardiomyocyte-specific processes such as contractile function, whereas ERRγ-mediated control of metabolic genes occurs independent of GATA4. Both mechanisms require the transcriptional coregulator PGC-1α. A disease-causing GATA4 mutation is shown to diminish PGC-1α/ERR/GATA4 cooperativity and expression of ERR target genes are downregulated in human heart failure samples suggesting that dysregulation of this circuitry may contribute to congenital and acquired forms of heart failure.


Assuntos
Fator de Transcrição GATA4 , Insuficiência Cardíaca , Células-Tronco Pluripotentes Induzidas , Receptores de Estrogênio , Fator de Transcrição GATA4/genética , Fator de Transcrição GATA4/metabolismo , Regulação da Expressão Gênica , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo
10.
Theranostics ; 12(1): 143-166, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34987639

RESUMO

Aims: Hypoxic-ischaemic encephalopathy (HIE) is one of the most serious complications in neonates and infants. Mesenchymal stromal cell (MSC)-based therapy is emerging as a promising treatment avenue for HIE. However, despite its enormous potential, the clinical application of MSCs is limited by cell heterogeneity, low isolation efficiency and unpredictable effectiveness. In this study, we examined the therapeutic effects and underlying mechanisms of human pluripotent stem cell-derived ectomesenchymal stromal cells (hPSC-EMSCs) in a rat model of HIE. Methods: hPSC-EMSCs were induced from either human embryonic stem cells or induced pluripotent stem cells. Stem cells or the conditioned medium (CM) derived from stem cells were delivered intracranially or intranasally to neonatal rats with HIE. Human umbilical cord-derived MSCs (hUC-MSCs) were used as the therapeutic comparison control and phosphate-buffered saline (PBS) was used as a negative control. Lesion size, apoptosis, neurogenesis, astrogliosis and microgliosis were evaluated. The rotarod test and Morris water maze were used to determine brain functional recovery. The PC-12 cell line, rat primary cortical neurons and neural progenitor cells were used to evaluate neurite outgrowth and the neuroprotective and neurogenesis effects of hPSC-EMSCs/hUC-MSCs. RNA-seq and enzyme-linked immunosorbent assays were used to determine the secretory factors that were differentially expressed between hPSC-EMSCs and hUC-MSCs. The activation and suppression of extracellular signal-regulated kinase (ERK) and cAMP response element-binding protein (CREB) were characterised using western blotting and immunofluorescent staining. Results: hPSC-EMSCs showed a higher neuroprotective potential than hUC-MSCs, as demonstrated by a more significant reduction in lesion size and apoptosis in the rat brain following hypoxia-ischaemia (HI). Compared with PBS treatment, hPSC-EMSCs promoted endogenous neurogenesis and alleviated astrogliosis and microgliosis. hPSC-EMSCs were more effective than hUC-MSCs. hPSC-EMSCs achieved a greater recovery of brain function than hUC-MSCs and PBS in rats with HIE. CM derived from hPSC-EMSCs had neuroprotective and neurorestorative effects in vitro through anti-apoptotic and neurite outgrowth- and neurogenesis-promoting effects. Direct comparisons between hPSC-EMSCs and hUC-MSCs revealed the significant enrichment of a group of secretory factors in hPSC-EMSCs, including nerve growth factor (NGF), platelet-derived growth factor-AA and transforming growth factor-ß2, which are involved in neurogenesis, synaptic transmission and neurotransmitter transport, respectively. Mechanistically, the CM derived from hPSC-EMSCs was found to potentiate NGF-induced neurite outgrowth and the neuronal differentiation of NPCs via the ERK/CREB pathway. Suppression of ERK or CREB abolished CM-potentiated neuritogenesis and neuronal differentiation. Finally, intranasal delivery of the CM derived from hPSC-EMSCs significantly reduced brain lesion size, promoted endogenous neurogenesis, mitigated inflammatory responses and improved functional recovery in rats with HIE. Conclusion: hPSC-EMSCs promote functional recovery after HI through multifaceted neuromodulatory activities via paracrine/trophic mechanisms. We propose the use of hPSC-EMSCs for the treatment of HIE, as they offer an excellent unlimited cellular source of MSCs.


Assuntos
Hipóxia-Isquemia Encefálica/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Animais , Células Cultivadas , Feminino , Humanos , Células-Tronco Pluripotentes Induzidas , Células-Tronco Mesenquimais , Pessoa de Meia-Idade , Células PC-3 , Cultura Primária de Células , Ratos
11.
Neuro Oncol ; 24(6): 872-885, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34655293

RESUMO

BACKGROUND: Neuroblastoma (NB) is a common childhood malignant tumor of neural crest (NC) origin with remarkable heterogeneity in outcomes. Amplification of the oncogene MYCN is strongly associated with highly malignant behaviour and poor prognosis. METHODS: This study aims to use a human embryonic stem cell (hESC)-derived NC model to identify novel downstream effectors of MYCN that can be potentially used as prognostic marker and/or therapeutic target. RESULTS: We show that MYCN-driven NB derived from human neural crest cells (hNCCs) recapitulate the pathological and molecular features of MYCN-amplified neuroblastoma (MNA-NB). By using this platform, we identify a group of 14 surface protein-encoding genes that are associated with MYCN expression level in MNA-NB. Among these genes, high CD55 expression is correlated with poor survival in MNA-NB but not in non-MNA-NB. Furthermore, CD55 promotes tumorigenesis, tumor growth, and cancer stemness in MNA-NB cell lines (MNA-NBL) through regulating the JNK pathway. Mechanistically, MYCN binds to both canonical and noncanonical E-boxes on the promoter of CD55 to regulate its transcriptional expression. Finally, neutralizing antibody targeting CD55 significantly attenuates cancer stemness, suppresses tumor growth, and improves survival exclusively in MNA-NBL-inoculated mice. CONCLUSION: MYCN shapes CD55 into a cancer stem cell regulator which represents a prognostic marker and therapeutic target of MNA-NB. The hESC-derived NC model serves as a valuable platform for investigating NB initiation and progression and developing potential therapeutic targets.


Assuntos
Células-Tronco Embrionárias Humanas , Neuroblastoma , Animais , Linhagem Celular Tumoral , Criança , Regulação Neoplásica da Expressão Gênica , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Embrionárias Humanas/patologia , Humanos , Camundongos , Proteína Proto-Oncogênica N-Myc/genética , Proteína Proto-Oncogênica N-Myc/metabolismo , Proteína Proto-Oncogênica N-Myc/uso terapêutico , Células-Tronco Neoplásicas/metabolismo , Crista Neural/metabolismo , Crista Neural/patologia , Neuroblastoma/genética , Fatores de Transcrição/genética
12.
J Formos Med Assoc ; 120(2): 883-892, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32919876

RESUMO

BACKGROUND/PURPOSE: Malignant hyperthermia (MH) is a life-threatening pharmacogenetic disease with only two known causative genes, RYR1 and CACNA1S. Both are huge genes containing numerous exons, and they reportedly only account for 50-70% of known MH patients. Next-generation sequencing (NGS) technology and bioinformatics could help delineate the genetic diagnosis of MH and several MH-like clinical presentations. METHODS: We established a capture-based targeted NGS sequencing framework to examine the whole genomic regions of RYR1, CACNA1S and the 16.6 Kb mitochondrial genome, as well as 12 other genes related to excitation-contraction coupling and/or skeletal muscle calcium homeostasis. We applied bioinformatics analyses to the variants identified in this study and also to the 48 documented RYR1 pathogenic variants. RESULTS: The causative variants were identified in seven of the eight (87.5%) MH families, but in none of the 10 individuals classified as either normal controls (N = 2) or patients displaying MH-like clinical features later found to be caused by other etiologies (N = 8). We showed that RYR1 c.1565A>G (p.Tyr522Cys)(rs118192162) could be a genetic hot spot in the Taiwanese population. Bioinformatics analyses demonstrated low population frequencies and predicted damaging effects from all known pathogenic RYR1 variants. We estimated that more than one in 1149 individuals worldwide carry MH pathogenic variants at RYR1. CONCLUSION: NGS and bioinformatics are sensitive and specific tools to examine RYR1 and CACNA1S for the genetic diagnosis of MH. Pathogenic variants in RYR1 can be found in the majority of MH patients in Taiwan.


Assuntos
Biologia Computacional , Hipertermia Maligna , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hipertermia Maligna/genética , Mutação , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Taiwan
13.
Environ Res ; 187: 109703, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32480025

RESUMO

BACKGROUND: Genetic variations in glutathione (GSH)-related and metallothionein (MT) genes, which are involved in producing enzymes in the methylmercury (MeHg) metabolism pathway, have been proposed as one of the reasons for the individual variability in MeHg toxicokinetics. OBJECTIVE: To investigate the impact of genetic variations in MT and GSH-related genes on the association of fish consumption with body burden of MeHg, as measured by hair Hg concentrations among young children and women of childbearing age. METHODS: A total of 179 unrelated children and 165 mothers with either high or low fish consumption were recruited from the community. Their hair total Hg (tHg) and MeHg levels and genotypes for SNPs located on the GCLC, GCLM, GPX1, GSTA1, GSTP1, MT1A, MT2A, and MT4 genes were determined. Based on their 14-day food records, the amounts of fish consumed and their MeHg intakes were estimated. The impact of genetic variations on hair Hg concentrations was examined by using Mann-Whitney tests and multivariable linear regression analyses. RESULTS: The presence of minor alleles of GCLC-129 (rs17883901), GPX1-198 (rs1050450) and MT1M (rs9936741) were associated with significantly lower hair tHg levels in mothers whereas mothers with minor alleles of GSTP1-105(rs1695) and MT1M (rs2270836) have significantly higher hair tHg levels. After adjustment for fish consumption and other confounding factors, apart from MT1M (rs2270836), all of the above SNPs remain significant in the multivariable linear regression models. CONCLUSIONS: Our results in a group of children and women show that genetic variants of GSH-related and MT genes are associated with hair Hg concentrations. These genetic variations are likely to significantly affect MeHg metabolism and thus influence the accumulation of Hg in the human body.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Animais , Criança , Pré-Escolar , Feminino , Peixes , Contaminação de Alimentos/análise , Variação Genética , Glutationa , Humanos , Mercúrio/análise , Metalotioneína/genética , Compostos de Metilmercúrio/análise , Projetos Piloto
14.
Circ Res ; 126(12): 1685-1702, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32212902

RESUMO

RATIONALE: The heart undergoes dramatic developmental changes during the prenatal to postnatal transition, including maturation of cardiac myocyte energy metabolic and contractile machinery. Delineation of the mechanisms involved in cardiac postnatal development could provide new insight into the fetal shifts that occur in the diseased heart and unveil strategies for driving maturation of stem cell-derived cardiac myocytes. OBJECTIVE: To delineate transcriptional drivers of cardiac maturation. METHODS AND RESULTS: We hypothesized that ERR (estrogen-related receptor) α and γ, known transcriptional regulators of postnatal mitochondrial biogenesis and function, serve a role in the broader cardiac maturation program. We devised a strategy to knockdown the expression of ERRα and γ in heart after birth (pn-csERRα/γ [postnatal cardiac-specific ERRα/γ]) in mice. With high levels of knockdown, pn-csERRα/γ knockdown mice exhibited cardiomyopathy with an arrest in mitochondrial maturation. RNA sequence analysis of pn-csERRα/γ knockdown hearts at 5 weeks of age combined with chromatin immunoprecipitation with deep sequencing and functional characterization conducted in human induced pluripotent stem cell-derived cardiac myocytes (hiPSC-CM) demonstrated that ERRγ activates transcription of genes involved in virtually all aspects of postnatal developmental maturation, including mitochondrial energy transduction, contractile function, and ion transport. In addition, ERRγ was found to suppress genes involved in fibroblast activation in hearts of pn-csERRα/γ knockdown mice. Disruption of Esrra and Esrrg in mice during fetal development resulted in perinatal lethality associated with structural and genomic evidence of an arrest in cardiac maturation, including persistent expression of early developmental and noncardiac lineage gene markers including cardiac fibroblast signatures. Lastly, targeted deletion of ESRRA and ESRRG in hiPSC-CM derepressed expression of early (transcription factor 21 or TCF21) and mature (periostin, collagen type III) fibroblast gene signatures. CONCLUSIONS: ERRα and γ are critical regulators of cardiac myocyte maturation, serving as transcriptional activators of adult cardiac metabolic and structural genes, an.d suppressors of noncardiac lineages including fibroblast determination.


Assuntos
Coração/embriologia , Miócitos Cardíacos/metabolismo , Receptores de Estrogênio/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Células Cultivadas , Regulação da Expressão Gênica no Desenvolvimento , Coração/crescimento & desenvolvimento , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Camundongos , Mitocôndrias Cardíacas/metabolismo , Miócitos Cardíacos/citologia , Receptores de Estrogênio/genética , Transdução de Sinais , Receptor ERRalfa Relacionado ao Estrogênio
15.
J Ethnopharmacol ; 254: 112714, 2020 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-32105750

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The Mallotus apelta (Lour.) Muell.Arg. is a well-known traditional Chinese medicine (TCM) used for anti-inflammatory, hemostasis and chronic hepatitis. AIM: The purpose of this study was to explore the antifibrotic effect of total flavonoids of Mallotus apelta leaf (TFM) and its potential mechanism. METHODS: Hepatic fibrosis was induced by carbon tetrachloride (CCl4) in rats. The CCl4-induced rats received intragastric administration of colchicine (0.2 mg/kg per day), TFM (25, 50, 100 mg/kg per day) and the equal vehicle was given to normal rats. Pathological evaluation in hepatic tissue were examined by hematoxylin and eosin (HE) staining. And the levels of serum biochemical parameters were detected by automatic biochemical analysis. Meanwhile, the collagen deposition in liver was observed by staining with Masson's trichrome. Collagenic parameters and inflammatory factors were measured by enzyme-linked immunosorbent assay (ELISA) kits. Additionally, corresponding assay kit was used to estimate the antioxidant enzyme and lipid peroxidation. In order to explore the potential mechanism of anti-fibrotic effects in TFM, the expressions of liver fibrosis related gene and protein were analyzed by real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot. RESULTS: The CCl4-induced hepatic fibrosis were inhibited dose-dependently in rats by TFM. The results showed that the key hallmarks of liver injury including aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), albumin (ALB) and total protein (TP) in the serum were reversed in CCl4-induced hepatic fibrosis rats which were treated by TFM. Furthermore, TFM significantly alleviates collagen accumulation and reduces the contents of hydroxyproline (Hyp), Type III precollagen (PC-III), collagen I (Col I), hyaluronic acid (HA) and laminin (LN). RT-PCR and Western blot results showed that TFM markedly inhibits liver fibrosis hallmark factor α-smooth muscle actin (α-SMA) expressions in CCl4-induced hepatic fibrosis rats. Moreover, TFM alleviated the oxidative stress and lipid peroxidation in rats induced by CCl4. TFM also attenuated the pro-inflammatory cytokines including interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) via inhibiting nuclear factor-κB (NF-κB) activation. Meanwhile, transforming growth factor-ß1 (TGF-ß1)/Smad signaling pathway was inhibited by TFM treatment. CONCLUSIONS: TFM can alleviate CCl4-induced hepatic fibrosis in rats, which potential mechanism may be due to its ability of reducing ECM accumulation, improving antioxidant and regulating TGF-ß1/Smad signaling pathways and NF-κB-dependent inflammatory response.


Assuntos
Flavonoides/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Mallotus (Planta) , Substâncias Protetoras/uso terapêutico , Animais , Tetracloreto de Carbono , Colágeno/metabolismo , Citocinas/sangue , Citocinas/genética , Flavonoides/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/sangue , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Folhas de Planta , Substâncias Protetoras/farmacologia , Ratos Sprague-Dawley , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo
16.
Neurol Res ; 42(1): 8-16, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31878844

RESUMO

Objectives: Long noncoding RNAs (lncRNAs) play substantial roles in cerebral ischemia. Growth arrest-specific 5 (GAS5) was reported to be involved in stroke. In the present study, we aimed to investigate the roles of GAS5 in cerebral condition and unveil the underlying mechanism.Method: Transient focal ischemia was induced by intraluminal occlusion of the right Middle cerebral artery occlusion (MCAO) and 2,3,5-triphenyltetrazolium chloride (TTC) staining was used to evaluate the volume of cerebral infarction. RT-qPCR was applied to evaluate the level of GAS5 and miR-221. Fluorescence activated Cell Sorting (FACS) and Terminal deoxynucleotidyl transferased (TUNEL)  were used for detection of apoptosis. Western blotting was applied for protein level. Luciferase assay was applied to reveal the underlying relationship between GAS5 and miR-221 or p53-upregulated modulator of apoptosis (PUMA) and miR-221.Results: The results indicated that GAS5 was up-regulated in MCAO rats and in vitro hypoxia cell model while miR-221 expression was decreased in vitro hypoxia cell model. GAS5 promoted cells apoptosis, while miR-221 inhibited cell apoptosis through regulation of PUMA and downstream JNK/H2AX signaling. Moreover, GAS5 and miR-221 have direct interaction and PUMA was the target of miR-221, indicating that GAS5 regulated PUMA through sponging miR-221.Conclusions: the present study revealed that GAS5 aggravated cell apoptosis in hypoxia condition via miR-221/PUMA axis, which may provide potential targets for the treatment of stroke.


Assuntos
Proteínas Reguladoras de Apoptose/biossíntese , Apoptose/fisiologia , Isquemia Encefálica/metabolismo , MicroRNAs/metabolismo , Neurônios/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Isquemia Encefálica/patologia , Hipóxia Celular/fisiologia , Células Cultivadas , Células HEK293 , Humanos , Masculino , Neurônios/patologia , Ratos , Ratos Sprague-Dawley , Regulação para Cima/fisiologia
17.
Mediators Inflamm ; 2019: 4693870, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31780859

RESUMO

Microbial lipopolysaccharides (LPS) have been implicated in the pathogenesis of rheumatoid arthritis (RA), possibly driving a systemic inflammatory response that may trigger the development and/or exacerbation of the disease. To explore the existence of this mechanism in African RA patients, we have measured systemic levels of LPS and its surrogate, LPS-binding protein (LBP), as well as those of intestinal fatty acid-binding protein (I-FABP), pulmonary surfactant protein D (SP-D), and cotinine in serum to identify possible origins of LPS, as well as associations of these biomarkers with rheumatoid factor (RF) and anticitrullinated peptide (aCCP) autoantibodies and the DAS 28-3 clinical disease severity score. A cohort of 40 disease-modifying antirheumatic drug-naïve, black South African RA patients rated by compound disease scores and 20 healthy subjects and 10 patients with chronic obstructive pulmonary disease (COPD) as controls were included in this study. Levels of the various biomarkers and autoantibodies were measured using a combination of ELISA and immunofluorimetric and immunoturbidometric procedures. LPS levels were lowest in the RA group compared to the healthy controls (p = 0.026) and COPD patients (p = 0.017), while LBP levels were also significantly lower in RA compared to the healthy individuals (p = 0.036). Levels of I-FABP and SP-D were comparable between all three groups. Categorisation of RA patients according to tobacco usage revealed the following significant positive correlations: LBP with C-reactive protein (p = 0.0137); a trend (p = 0.073) towards an association of LBP with the DAS 28-3 disease severity score; RF-IgG antibodies with both LPS and LBP (p = 0.033 and p = 0.041, respectively); aCCP-IgG antibodies with LPS (p = 0.044); and aCCP-IgG with RF-IgM autoantibodies (p = 0.0016). The findings of this study, several of them novel, imply that tobacco products, as opposed to microbial translocation, represent a potential source of LPS in this study cohort of RA patients, again underscoring the risks posed by tobacco usage for the development and severity of RA.


Assuntos
Artrite Reumatoide/induzido quimicamente , Lipopolissacarídeos/química , Artrite Reumatoide/sangue , Biomarcadores/sangue , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Ensaio de Imunoadsorção Enzimática , Proteínas de Ligação a Ácido Graxo/metabolismo , Feminino , Humanos , Masculino , Fator Reumatoide/metabolismo , Nicotiana/química
18.
Cell Mol Life Sci ; 76(19): 3891-3898, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31053884

RESUMO

Statins are potent lipid-lowering drugs. Large prospective clinical trials have shown the anti-thrombotic effect of statins, e.g., preventing deep vein thrombosis. However, the mechanism underlying the beneficial effect of statins in reducing thrombus formation remains to be established. We, thus, conduct this study to investigate the potential molecular mechanisms. The cultured human hepatoma cells (HepG2) were used as the in vitro model. The human protein C gene promoter was cloned into the luciferase reporter to study the transcriptional regulation of human protein C gene. Wistar rats fed with simvastatin (5 mg/kg day) were used as the in vivo model. We found that simvastatin increased the expression of protein C in hepatocytes (361 ± 64% and 313 ± 59% after 2 h and 6 h of stimulation, respectively, both p < 0.01). In the animal study, the serum protein C levels were increased in the simvastatin-treated group (7 ± 2.2 unit/ml vs 23.4 ± 19.3 unit/ml and 23.4 ± 18.2 unit/ml and 1 and 2 weeks of treatment, respectively, both p < 0.05). Regarding the possible molecular mechanism, we found that the level of hepatocyte nuclear factor 1α (HNF1α) was also increased in both the in vivo and in vitro models. We found that the protein C promoter activity was increased by simvastatin, and this effect was inhibited by HNF1α knockdown and constitutively active Rac1. Therefore, stains may modulate protein C expression through small GTPase Rac 1 and HNF1α.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Proteína C/genética , Animais , Células Hep G2 , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Humanos , Regiões Promotoras Genéticas/efeitos dos fármacos , Proteína C/metabolismo , Ratos Wistar , Sinvastatina/farmacologia , Transcrição Gênica/efeitos dos fármacos , Proteínas rac1 de Ligação ao GTP/genética
19.
Mol Cancer Ther ; 18(3): 706-717, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30523048

RESUMO

Tumor heterogeneity is a major challenge for cancer treatment, especially due to the presence of various subpopulations with stem cell or progenitor cell properties. In mouse melanomas, both CD34+p75- (CD34+) and CD34-p75- (CD34-) tumor subpopulations were characterized as melanoma-propagating cells (MPC) that exhibit some of those key features. However, these two subpopulations differ from each other in tumorigenic potential, ability to recapitulate heterogeneity, and chemoresistance. In this study, we demonstrate that CD34+ and CD34- subpopulations carrying the BRAFV600E mutation confer differential sensitivity to targeted BRAF inhibition. Through elevated KDM5B expression, melanoma cells shift toward a more drug-tolerant, CD34- state upon exposure to BRAF inhibitor or combined BRAF inhibitor and MEK inhibitor treatment. KDM5B loss or inhibition shifts melanoma cells to the more BRAF inhibitor-sensitive CD34+ state. These results support that KDM5B is a critical epigenetic regulator that governs the transition of key MPC subpopulations with distinct drug sensitivity. This study also emphasizes the importance of continuing to advance our understanding of intratumor heterogeneity and ultimately develop novel therapeutics by altering the heterogeneous characteristics of melanoma.


Assuntos
Antígenos CD34/genética , Proteínas de Ligação a DNA/genética , Histona Desmetilases com o Domínio Jumonji/genética , Melanoma/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Animais , Linhagem Celular Tumoral , Linhagem da Célula/efeitos dos fármacos , Linhagem da Célula/genética , Proliferação de Células/genética , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , MAP Quinase Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase Quinase 1/genética , Melanoma/genética , Melanoma/patologia , Camundongos , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Sulfonamidas/farmacologia , Vemurafenib/farmacologia
20.
Cancer Cell Int ; 18: 156, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30337838

RESUMO

BACKGROUND: As newly identified Wnt enhancer, R-spondin gene family members have been linked to various cancers; however, their role in isocitrate dehydrogenase-wildtype subtype of human glioblastoma (GBM) cells remains unknown. METHODS: Human U87 and U251 cell lines were used to perform the experiments. GBM stem-like cells were enriched in stem cell growth media and induced to differentiate using retinoid acid or growth factor deprivation. Wnthigh and Wntlow subpopulations were isolated and evaluated by MTS, sphere formation, transwell migration and xenograft formation assays. RESULTS: R-spondin 2 but not R-spondin 3 potentiates Wnt/ß-catenin signaling in GBM cell lines. While R-spondin 2 does not affect cell growth, it induces the expression of pluripotent stem cell markers in combination with Wnt3A. GBM stem-like cells are endowed with intrinsic high activity of ß-catenin signaling, which can be further intensified by R-spondin 2. In addition, R-spondin2 promotes stem cell self-renewal and suppresses retinoid acid- or growth factor deprivation-induced differentiation, indicating R-spondin 2 maintains stem cell traits in GBM. On the other hand, we identify subpopulations of GBM cells that show distinctive responsiveness to Wnt/ß-catenin signaling. Interestingly, Wnthigh and Wntlow cells display distinctive biologic properties. Moreover, Wnthigh cell-inoculated xenografts exhibit enhanced tumorigenicity and increased expression levels of R-spondin 2 compared to Wntlow cell-inoculated xenografts. CONCLUSION: Our study reveals a novel regulatory mechanisms underlying the over-activation of ß-catenin-mediated signaling in the pathogenesis of GBM.

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