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1.
Sci Total Environ ; 699: 134397, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31677469

RESUMO

Children are vulnerable to air pollution-induced lung function deficits, and the prevalence of obesity has been increasing in children. To evaluate the joint effects of long-term PM1 (particulate matter with an aerodynamic diameter ≤ 1.0 µm) exposure and obesity on children's lung function, a cross-sectional sample of 6740 children (aged 7-14 years) was enrolled across seven northeastern Chinese cities from 2012 to 2013. Weight and lung function, including forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), peak expiratory flow (PEF), and maximal mid-expiratory flow (MMEF), were measured according to standardized protocols. Average PM1, PM2.5, PM10 and nitrogen dioxide (NO2) exposure levels were estimated using a spatiotemporal model, and sulphur dioxide (SO2) and ozone (O3) exposure were estimated using data from municipal air monitoring stations. Two-level logistic regression and general linear models were used to analyze the joint effects of body mass index (BMI) and air pollutants. The results showed that long-term air pollution exposure was associated with lung function impairment and there were significant interactions with BMI. Associations were stronger among obese and overweight than normal weight participants (the adjusted odds ratios (95% confidence intervals) for PM1 and lung function impairments in three increasing BMI categories were 1.50 (1.07-2.11) to 2.55 (1.59-4.07) for FVC < 85% predicted, 1.44 (1.03-2.01) to 2.51 (1.53-4.11) for FEV1 < 85% predicted, 1.34 (0.97-1.84) to 2.04 (1.24-3.35) for PEF < 75% predicted, and 1.34 (1.01-1.78) to 1.93 (1.26-2.95) for MMEF < 75% predicted). Consistent results were detected in linear regression models for PM1, PM2.5 and SO2 on FVC and FEV1 impairments (PInteraction < 0.05). These modification effects were stronger among females and older participants. These results can provide policy makers with more comprehensive information for to develop strategies for preventing air pollution induced children's lung function deficits among children.


Assuntos
Poluição do Ar/estatística & dados numéricos , Exposição Ambiental/estatística & dados numéricos , Obesidade/epidemiologia , Adolescente , Poluentes Atmosféricos/análise , Criança , China/epidemiologia , Cidades , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/efeitos dos fármacos , Masculino , Dióxido de Nitrogênio/análise , Sobrepeso , Ozônio/análise , Material Particulado/análise , Testes de Função Respiratória , Dióxido de Enxofre , Capacidade Vital
2.
Gene ; : 144271, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31809841

RESUMO

Aoluguya Reindeer is the only reindeer population in China. In recent years, habitat loss and inbreeding have led to population decline, and population growth has been slow, maintaining a thousand or so. To better protect the Aoluguya Reindeer and improve its fecundity, we have introduced reindeer from Finland, crossbreeding help us to reach this goal. However, it is lacking in the study of genetic diversity of reindeer in China and Finland. Therefore, we used the partial sequences of the D-loop region of mitochondrial DNA to analyze the genetic diversity of Chinese reindeer (Aoluguya Reindeer) and the introduced Finnish reindeer, and identified twenty-six haplotypes, including nineteen in China, five in Finland, and two in Russia. There is no shared haplotype among them. The nucleotide diversity of Aoluguya Reindeer is 0.00752, which is significantly lower than that of reindeer in Finland and other countries. The haplotype and phylogenetic analysis show that reindeer from different geographical origins are not clustered completely according to geographical distribution. Aoluguya Reindeer populations and the introduced reindeer herds from Finland are all closely related to the reindeer from Russia. AMOVA analysis showed that there was significant differentiation between reindeer populations in China and Finland, and mismatch analysis showed that both populations had not experienced expansion. In this study, we identified the genetic diversity of Aoluguya Reindeer and the introduced reindeer, and provided a scientific basis for the conservation and breeding of Aoluguya Reindeer resources.

3.
Environ Int ; 131: 104943, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295644

RESUMO

To assess the carcinogenic potential of PM2.5 exposure, we developed a cell-based experimental protocol to examine the cell transformation activity of PM2.5 samples from different regions in China. The seasonal ambient PM2.5 samples were collected from three megacities, Beijing (BJ), Wuhan (WH), and Guangzhou (GZ), from November 2016 to October 2017. The mean concentrations of PM2.5 were much higher in the winter season (BJ: 109.64 µg/m3, WH: 79.99 µg/m3, GZ: 49.99 µg/m3) than that in summer season (BJ: 42.40 µg/m3, WH: 25.82 µg/m3, GZ: 19.82 µg/m3). The organic extracts (OE) of PM2.5 samples from combined summer (S) (June, July, August) or winter (W) (November, December, January) seasons were subjected to characterization of chemical components. We treated human bronchial epithelial (HBE) cells expressing CYP1A1 (HBE-1A1) with PM2.5 samples at doses ranging from 0 to 100 µg/mL (0, 1.563, 3.125, 6.25, 12.5, 25, 50, 100 µg/mL) and determined the phenotype of malignant cell transformation. A dose-response relationship was analyzed by benchmark dose (BMD) modeling, and the potential were indicated by BMDL10. The order of the carcinogenic risk of seasonal PM2.5 samples from high to low was BJ-W, WH-W, GZ-W, WH-S, BJ-S, and GZ-S. Notably, we found that the alteration in the lung cancer-related biomarkers, KRAS, PTEN, p53, c-Myc, PCNA, pAKT/AKT, and pERK/ERK was congruent with the activity of cell transformation and the content of specific components of polycyclic aromatic hydrocarbon (PAHs) bound to PM2.5. Taken together, we have successfully developed a cell-based alternative model for the evaluation of potent carcinogenicity upon long-term PM2.5 exposure.

4.
Environ Pollut ; 252(Pt A): 607-615, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31185349

RESUMO

Coke oven emissions (COEs) are common particle pollutants in occupational environment and the major constituents of COEs are polycyclic aromatic hydrocarbons (PAHs). Previously, we identified aberrant methylation of the fms related tyrosine kinase 1 (FLT1) gene over the course of benzo(a)pyrene (BaP)-induced cell transformation via genome-wide methylation array. To quantify FLT1 methylation, we established a bisulfite pyrosequencing assay and examined the FLT1 hypermethylation in several human cancers. The results revealed that 70.0% (21/30 pairs) of lung cancers harbored hypermethylated FLT1 and concomitant suppression of gene expression compared to the adjacent tissues. This implies that FLT1 hypermethylation might play a role in malignant cell transformation. In addition, FLT1 hypermethylation and gene suppression appeared in primary human lymphocytes in a dose-response manner following COEs treatment. To explore whether FLT1 methylation is correlated with COEs exposure and DNA damage, we recruited 144 male subjects who had been exposed to high levels of COEs and 84 male control subjects. Notably, the FLT1 methylation in peripheral blood lymphocytes (PBLCs) of the COEs-exposed group (19.8 ±â€¯3.2%) was enhanced by 17.9% compared to that of the control group (16.8 ±â€¯2.8%) (P < 0.001). The FLT1 methylation status was positively correlated with urinary 1-hydroxypyrene (1-OHP) levels, an internal exposure marker of PAHs (ß = 0.029, 95% CI = 0.010-0.048, P = 0.003) and positively correlated with DNA damage (ßOTM = 0.024, 95% CI = 0.007-0.040, P = 0.005; ßTail DNA = 0.035, 95% CI = 0.0017-0.054, P < 0.001) indicated by comet assay. Taken together, these findings indicate that FLT1 might be a tumor suppressor, and its hypermethylation might contribute to PAHs-induced carcinogenicity.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Adulto , Poluentes Ocupacionais do Ar/análise , Benzo(a)pireno/metabolismo , Biomarcadores/metabolismo , Transformação Celular Neoplásica/metabolismo , Coque , Ensaio Cometa , Dano ao DNA , Metilação de DNA , Humanos , Linfócitos/metabolismo , Masculino , Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos/análise , Pirenos/metabolismo , Sulfitos , Receptor 1 de Fatores de Crescimento do Endotélio Vascular
5.
Int J Mol Sci ; 20(9)2019 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-31035421

RESUMO

Embryo implantation in the mink follows the pattern of many carnivores, in that preimplantation embryo diapause occurs in every gestation. Details of the gene expression and regulatory networks that terminate embryo diapause remain poorly understood. Illumina RNA-Seq was used to analyze global gene expression changes in the mink uterus during embryo diapause and activation leading to implantation. More than 50 million high quality reads were generated, and assembled into 170,984 unigenes. A total of 1684 differential expressed genes (DEGs) in uteri with blastocysts in diapause were compared to the activated embryo group (p < 0.05). Among these transcripts, 1527 were annotated as known genes, including 963 up-regulated and 564 down-regulated genes. The gene ontology terms for the observed DEGs, included cellular communication, phosphatase activity, extracellular matrix and G-protein couple receptor activity. The KEGG pathways, including PI3K-Akt signaling pathway, focal adhesion and extracellular matrix (ECM)-receptor interactions were the most enriched. A protein-protein interaction (PPI) network was constructed, and hub nodes such as VEGFA, EGF, AKT, IGF1, PIK3C and CCND1 with high degrees of connectivity represent gene clusters expected to play an important role in embryo activation. These results provide novel information for understanding the molecular mechanisms of maternal regulation of embryo activation in mink.


Assuntos
Blastocisto/metabolismo , Útero/metabolismo , Animais , Blastocisto/fisiologia , Implantação do Embrião/genética , Implantação do Embrião/fisiologia , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Feminino , Vison , Gravidez , Transcriptoma/genética , Útero/fisiologia
6.
BMC Genomics ; 20(1): 384, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101010

RESUMO

BACKGROUND: Previous investigations of phylogeny in Cervus recovered many clades without whole genomic support. METHODS: In this study, the genetic diversity and phylogeny of 5 species (21 subspecies/populations from C. unicolor, C. albirostris, C. nippon, C. elaphus and C. eldii) in the genus Cervus were analyzed using reduced-representation genome sequencing. RESULTS: A total of 197,543 SNPs were identified with an average sequencing depth of 16 x. A total of 21 SNP matrices for each subspecies/population and 1 matrix for individual analysis were constructed, respectively. Nucleotide diversity and heterozygosity analysis showed that all 21 subspecies/populations had different degrees of genetic diversity. C. eldii, C. unicolor and C. albirostris showed relatively high expected and observed heterozygosity, while observed heterozygosity in C. nippon was the lowest, indicating there was a certain degree of inbreeding rate in these subspecies/populations. Phylogenetic ML tree of all Cervus based on the 21 SNP matrices showed 5 robustly supported clades that clearly separate C. eldii, C. unicolor, C. albirostris, C. elaphus and C. nippon. Within C. elaphus clade, 4 subclades were well differentiated and statistically highly supported: C. elaphus (New Zealand), C. e. yarkandensis, C. c. canadensis and the other grouping the rest of C. canadensis from China. In the C. nippon clade, 2 well-distinct subclades corresponding to C. n. aplodontus and other C. nippon populations were separated. Phylogenetic reconstruction indicated that the first evolutionary event of the genus Cervus occurred approximately 7.4 millions of years ago. The split between C. elaphus and C. nippon could be estimated at around 3.6 millions of years ago. Phylogenetic ML tree of all samples based on individual SNP matrices, together with geographic distribution, have shown that there were 3 major subclades of C. elaphus and C. canadensis in China, namely C. e. yarkandensis (distributed in Tarim Basin), C. c. macneilli/C. c. kansuensis/C. c. alashanicus (distributed in middle west of China), and C. c. songaricus/C. c. sibiricus (distributed in northwest of China). Among them, C. e. yarkandensis was molecularly the most primitive subclade, with a differentiation dating back to 0.8-2.2 Myr ago. D statistical analysis showed that there was high probability of interspecific gene exchange between C. albirostris and C. eldii, C. albirostris and C. unicolor, C. nippon and C. unicolor, and there might be 2 migration events among 5 species in the genus Cervus. CONCLUSIONS: Our results provided new insight to the genetic diversity and phylogeny of Cervus deer. In view of the current status of these populations, their conservation category will need to be reassessed.


Assuntos
Cervos/classificação , Cervos/genética , Variação Genética , Estudo de Associação Genômica Ampla , Genoma , Genômica/métodos , Filogenia , Animais , Evolução Biológica , Sequenciamento de Nucleotídeos em Larga Escala
7.
Environ Pollut ; 247: 293-301, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30685670

RESUMO

The growing production and extensive use of organophosphate flame retardants (OPFRs) have led to an increase in their environmental distribution and human exposure. Developmental toxicity is a major concern of OPFRs' adverse health effects. However, the impact of OPFRs exposure on vascular development and the toxicity pathway for developmental defects are poorly understood. In this study, we investigated the effects of exposure to tris(1,3-dichloro-2-propyl) phosphate (TDCPP), a frequently detected OPFR, on early vascular development, and the possible role of nuclear factor erythroid 2-related factor (Nrf2)-dependent angiogenic pathway in TDCPP's vascular toxicity. TDCPP exposure at 300 and 500 µg/L impeded the growth of intersegmental vessels (ISV), a type of microvessels, as early as 30 hpf. Consistently, a similar pattern of decreased extension and remodeling of common cardinal vein (CCV), a typical macrovessel, was observed in zebrafish at 48 hpf and 72 hpf. Developing vasculature in zebrafish was more sensitive than general developmental parameters to TDCPP exposure. The expression of genes related to VEGF signaling pathway dose-dependently decreased in TDCPP-treated larvae. In in vitro experiments using human umbilical vein endothelial cells (HUVECs), the increased cell proliferation induced by VEGF was suppressed by TDCPP exposure in a dose-dependent fashion. In addition, we found a repression of Nrf2 expression and activity in TDCPP-treated larvae and HUVECs. Strikingly, the application of CDDO-Im, a potent Nrf2 activator, enhanced VEGF and protected against defective vascular development in zebrafish. Our results reveal that vascular impairment is a sensitive index for early exposure to TDCPP, which could be considered in the environmental risk assessment of OPFRs. The identification of Nrf2-mediating VEGF pathway provides new insight into the adverse outcome pathway (AOP) of OPFRs.


Assuntos
Retardadores de Chama/toxicidade , Compostos Organofosforados/toxicidade , Fator A de Crescimento do Endotélio Vascular/metabolismo , Peixe-Zebra/fisiologia , Animais , Retardadores de Chama/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Larva/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Organofosfatos/metabolismo , Fosfatos/metabolismo , Peixe-Zebra/metabolismo
8.
Mol Genet Genomics ; 294(2): 431-443, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30539301

RESUMO

Velvet antler displays the fastest and most robust tissue proliferation in the animal world, it is a model for a complete organ development/regeneration, and alternative medicine, tonic made from velvet antler, was beneficial for human. The weight of velvet antler had high biomedical and economic value, but the related regulation mechanisms controlling velvet antler weight remain unclear. In this study, extremely heavy and light velvet antler groups were selected from a sika deer population of 100 individuals with extreme velvet antler weight. A combination of full-length transcriptome sequencing and microRNA sequencing to the proliferation zone in the tip of velvet antler was applied. A total of 55306 transcripts and 1082 microRNAs were identified. Some highly expressed genes (COL1A1, COL1A2, COL3A1, FN1, and ATP6) and microRNAs (miR-21, let-7i, and miR-27b) were highly correlated with the physiological and growth characteristics of velvet antlers. Among the 334 differentially expressed genes, we found that most of the genes were located in the developmental process, especially animal organ development process. It is exciting to see that more blood vessels were found in the growing tip of heavy velvet antler through histological observation, and GO term of blood vessel development was also significant different between two groups. The combination analysis with mRNA and microRNA data in velvet antler showed a specific regulation network involved in the development of bone, mesenchyme, cartilage, and blood vessel, and helped us clearly find out the candidate 14 genes and 6 microRNAs, which could be used for selecting significant DNA markers of velvet antler weight.


Assuntos
Chifres de Veado/crescimento & desenvolvimento , Cervos/crescimento & desenvolvimento , MicroRNAs/genética , Transcriptoma/genética , Animais , Cervos/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Redes Reguladoras de Genes/genética , Humanos , Regeneração/genética
9.
Artigo em Inglês | MEDLINE | ID: mdl-29658380

RESUMO

Aoluguya Reindeer is the only reindeer species in China and currently approximately 1000 Aoluguya Reindeer remain semi-domesticated. A relative low diversity estimate was found by investigating genetic variability and demographic history of its population. Mismatch distribution curve of its nucleotide sequences and neutral test indicate its population has not experienced expansion. Genetic diversity and population structure were also analysed by using its mtDNA and microsatellites technology. Statistical results of these analyses showed there were varying degrees of population inbreeding and suggested that gene flow existed among its populations at one time. Three mutation models were also used to detect the bottleneck effect of reindeer population. The genetic variation of eight populations is relatively small. In addition, the clustering program STRUCTURE was used to analyse Aoluguya Reindeer population structure, to determine its optimal K and first time to analyse the phylogenetic status of Aoluguya Reindeer among other reindeer subspecies. It is recommended that the government establish a natural conservation area in Aoluguya Reindeer growing geography, forbade the trade and hunting of Aoluguya Reindeer, and strengthen the protection of this endangered species.


Assuntos
DNA Mitocondrial/genética , Espécies em Perigo de Extinção , Polimorfismo Genético , Rena/genética , Animais , China , Repetições de Microssatélites
10.
Toxicology ; 412: 19-28, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30503582

RESUMO

Primary mouse hepatocyte cultures are widely used in toxicological and pharmacological studies. However, the strain differences in alterations of metabolic enzymes and the regulation of gene expression in response to different stimuli remains unclear. To address this issue, we examined the expression of metabolic enzymes and the regulatory role of DNA methylation in the primary hepatocytes of two mouse strains, CD-1 and C57BL/6. Primary culture of mouse hepatocytes was established using collagen sandwich configuration. Analysis of gene expression of 24 phase I, 18 phase II, and 6 phase III metabolic enzymes on 4 consecutive days after cell seeding revealed that the basal levels of most enzymes in primary cultured hepatocytes differed greatly between the two mouse strains. However, the dynamic changes in most genes were identical between the two strains. In addition, treatment with 3-methylcholanthrene, phenobarbital, and rifampin led to the induction of cytochrome P-450 (cyp) 1a1 and cyp1a2, cyp2b10, cyp3a11. However, induction varied in degree between the two types of primary hepatocytes. The dynamic changes in global DNA methylation and the expression of DNA methylation regulatory factors of the two mouse strains were similar. Of the genes down-regulated over the culture period, hypermethylation of cyp2e1 gene appeared in both mouse strains and led to a suppression of gene expression. Taken together, these results demonstrate that the expression of metabolic enzymes and the response to agonists in primary hepatocytes differ between CD-1 and C57BL/6 mouse strains. Epigenetic regulation might be involved in the suppression of cyp 450s' expression.


Assuntos
Metilação de DNA , Regulação Enzimológica da Expressão Gênica , Hepatócitos/enzimologia , Animais , Células Cultivadas , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Especificidade da Espécie
11.
Toxicol Appl Pharmacol ; 358: 56-67, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30195019

RESUMO

Previous studies have demonstrated that oxidative stress is implicated in benzene-induced hematotoxicity. However, the low dose-response effects and the mechanism underlying perturbation of hematopoiesis remain to be defined. This study aims to address the role of Nrf2 pathway in mediating benzene-induced hematotoxicity. Nrf2+/+ (wildtype, Nrf2-WT) and Nrf2-/- (knockout, Nrf2-KO) mice were administrated with benzene at doses of 0.1, 1.0, 10.0, 100.0 mg/kg by oral gavage for a consecutive 4 weeks (6 times/week). As a result, benzene exposure caused a decline of WBC and lymphocyte counts in a dose-dependent manner at a dose range from 1.0 to 100.0 mg/kg, while low dose benzene induced hormesis effects. Interestingly, Nrf2 deficiency seemed to relieve the decline of peripheral blood cell counts upon benzene exposure, indicating the involvement of Nrf2 in regulation of benzene-induced hematotoxicity. The suppression of phase II enzyme expression in Nrf2-KO mice resulted in considerable reduction in detoxification indicated by the decrease of urinary S-phenylmercapturic acid (SPMA), a metabolite of benzene. Ex vivo assay revealed enhanced cytotoxicity and oxidative stress were induced by benzene in Nrf2-KO mice. Notably, the depletion of Nrf2 triggered the proliferation and differentiation of hematopoietic cells, but induced aberrant morphological changes in periphery erythrocytes and bone marrow cells, implicating the compensatory effects carried on at the expense of induction of dysfunctional blood cells. Our findings provide a new insight into a low dose-response towards benzene-induced hematotoxicity and uncover the critical role of Nrf2 pathway in mediating abnormal hematopoiesis in response to oxidative stress.


Assuntos
Benzeno/toxicidade , Hematopoese/efeitos dos fármacos , Hematopoese/fisiologia , Fator 2 Relacionado a NF-E2/deficiência , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/fisiologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Eritrócitos/fisiologia , Células HL-60 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Distribuição Aleatória
12.
Aquat Toxicol ; 203: 19-27, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30071320

RESUMO

Polybrominated diphenyl ethers (PBDEs) are persistent flame retardants ubiquitously existing in various environment matrices. In spite of a recent reduction in use according to the phase-out policy, high levels of PBDEs are still found in both environmental and biological samples due to their persistent property and large-scale production over a long history. Developmental toxicity is a major health concern of PBDEs. However, the impact of PBDE exposure on vascular development remains poorly understood. In this study, we investigated the effect of low concentrations of 2,2',4,4'-Tetrabromodiphenyl ether (BDE-47), a predominant PBDE congener, in environmental matrices and biota, on early vascular development using zebrafish. Zebrafish embryos were continuously exposed to waterborne BDE-47 at 0.06, 0.2, 0.6 µM starting from 2 h post-fertilization (hpf). Fluorescent images of vasculatures in Tg(kdrl:eGFP) zebrafish were acquired using a confocal microscope. The results indicated that BDE-47 exposure had no effect on hatching rate, survival, body weight, body length or heart rate in the early stage within 72 hpf, whereas zebrafish exposed to BDE-47 exhibited impairments in the growth of multiple types of blood vessels. The percentage of completed intersegmental vessels (ISV) at 30 hpf decreased in embryos treated with BDE-47 in a dose-dependent fashion. BDE-47 exposure led to a slight decrease in the growth of common cardinal vein (CCV), while dramatically hindered CCV remodeling process reflected by the larger CCV area and wider ventral diameter. BDE-47 exposure significantly reduced sub-intestinal vessels (SIV) area as well as the vascularized yolk area in zebrafish larvae at 72 hpf. In addition, the expression of genes related to vascular growth and remodeling was markedly suppressed in BDE-47-exposed zebrafish. These findings demonstrate the adverse effects of BDE-47 on early vascular development, and confirm the vascular toxicity of PBDEs in vivo. The results indicate that developing vasculature in zebrafish is sensitive to BDE-47 exposure, and may serve as a powerful tool for the assessment of early exposure to PBDEs.


Assuntos
Vasos Sanguíneos/crescimento & desenvolvimento , Exposição Ambiental/análise , Éteres Difenil Halogenados/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia , Peixe-Zebra/crescimento & desenvolvimento , Animais , Animais Geneticamente Modificados , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/embriologia , Peso Corporal/efeitos dos fármacos , Retardadores de Chama/toxicidade , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Larva/efeitos dos fármacos , Testes de Toxicidade , Remodelação Vascular/efeitos dos fármacos , Remodelação Vascular/genética , Peixe-Zebra/anatomia & histologia , Peixe-Zebra/genética
13.
Mol Genet Genomics ; 293(3): 769-783, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29383448

RESUMO

Gene knockdown and knockout using RNAi and CRISPR/Cas9 allow for efficient evaluation of gene function, but it is unclear how the choice of technology can influence the results. To compare the phenotypes obtained using siRNA and CRISPR/Cas9 technologies, aldehyde dehydrogenase 2 (ALDH2) was selected as an example. In this study, we constructed one HepG2 cell line with a homozygous mutation in the fifth exon of ALDH2 (ALDH2-KO1 cell) using the eukaryotic CRISPR/Cas9 expression system followed by the limited dilution method and one HepG2 cell line with different mutations in the ALDH2 gene (ALDH2-KO2 cell) using the lentivirus CRISPR/Cas9 system. Additionally, one ALDH2-knockdown (KD) HepG2 cell line was created using siRNA. The reproducibility of these methods was further verified in the HEK293FT cell line. We found that the mRNA expression level of ALDH2 was significantly decreased and the protein expression level of ALDH2 was completely abolished in the ALDH2-KO cell lines, but not in ALDH2-KD cells. Furthermore, the functional activity of ALDH2 was also markedly disrupted in the two ALDH2-KO cell lines compared with ALDH2-KD and wild-type cells. The lack of ALDH2 expression mediated by CRIPSR/Cas9 resulted in a more dramatic increase in the cellular susceptibility to chemical-induced reactive oxygen species generation, cytotoxicity, apoptosis, and inflammation, especially at low concentrations compared with ALDH2-KD and WT cells. Therefore, we consider the gene knockout cell line created by CRISPR/Cas9 to be a more useful tool for identifying the function of a gene.


Assuntos
Aldeído-Desidrogenase Mitocondrial/genética , Sistemas CRISPR-Cas , RNA Interferente Pequeno/genética , Aldeído-Desidrogenase Mitocondrial/metabolismo , Regulação da Expressão Gênica , Inativação Gênica , Células HEK293 , Células Hep G2 , Homozigoto , Humanos , Mutação , Fenótipo , Reprodutibilidade dos Testes
14.
Oncotarget ; 9(4): 4915-4923, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29435151

RESUMO

Epidemiologic study has suggested that arsenic exposure is positively related to increased blood pressure. However, the underlying mechanism concerning interaction between genetic polymorphisms and arsenic exposure remains unclear. In present study, within 395 Chinese, the effects of interaction between arsenic exposure and CCM3 gene polymorphisms on elevation of blood pressure were probed by multiple Logistic regression models after adjusting for confounding factors. Firstly, we found that serum arsenic was positively associated with blood pressure, cholesterol, glucose and C-reactive protein. Then, adjusted for confounding factors of age, gender, smoking, alcohol consumption, BMI and degree of education, arsenic exposure incurred the hazard of increased systolic pressure and diastolic pressure, with odds ratios (ORs) being 1.725 and 1.425, respectively. Distinctly, we found that interactions between rs3804610* rs9818496, rs6784267*rs9818496, and rs3804610* rs6784267 variant genotype can increase significantly risks of SBP. Additionally, interactions between rs9818496, rs3804610 and rs6784267 genotypic variantions and arsenic exposure boosted the hazard of increased systolic pressure, with ORs being 1.496, 1.496 and 1.312. In conclusion, our fingdings suggest that As exposure of population can assist CCM3 polymorphism in elevating SBP.

15.
Environ Pollut ; 234: 127-135, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29175474

RESUMO

In this study, we explore whether altered global histone modifications respond to low-level benzene exposure as well as their association with the hematotoxicity. We recruited 147 low-level benzene-exposed workers and 122 control workers from a petrochemical factory in Maoming City, Guangdong Province, China. The internal exposure marker level, urinary S-phenylmercapturic acid (SPMA), in benzene-exposed workers was 1.81-fold higher than that of the controls (P < 0.001). ELISA method was established to examine the specific histone modifications in human peripheral blood lymphocytes (PBLCs) of workers. A decrease in the counts of white blood cells (WBC), neutrophils, lymphocytes, and monocytes appeared in the benzene-exposed group (all P < 0.05) compared to the control group. Global trimethylated histone 3 lysine 4 (H3K4me3) modification was enhanced in the benzene-exposed group (P < 0.05) and was positively associated with the concentration of urinary SPMA (ß = 0.103, P = 0.045) and the extent of DNA damage (% Tail DNA: ß = 0.181, P = 0.022), but was negatively associated with the leukocyte count (WBC: ß = -0.038, P = 0.023). The in vitro study revealed that H3K4me3 mark was enriched in the promoters of several DNA damage responsive (DDR) genes including CRY1, ERCC2, and TP53 in primary human lymphocytes treated with hydroquinone. Particularly, H3K4me3 modification was positively correlated with the expression of CRY1 in the PBLCs of benzene-exposed workers. These observations indicate that H3K4me3 modification might mediate the transcriptional regulation of DDR genes in response to low-dose benzene exposure.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Benzeno/toxicidade , Dano ao DNA/genética , Histonas/metabolismo , Exposição Ocupacional , Acetilcisteína/análogos & derivados , Acetilcisteína/urina , Adulto , Biomarcadores/urina , China , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Masculino , Metilação , Pessoa de Meia-Idade , Ativação Transcricional
16.
Gene ; 642: 505-512, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29196255

RESUMO

Cell immortalization is the initial step for cancer development. To identify the differentially expressed genes regulated by DNA methylation over the course of human primary bronchial epithelial cell (HPBECs) immortalization, an immortalized HBE cell line (HBETT) was generated via introduction of an SV40 LT and a catalytic subunit of human telomerase reverse transcriptase (hTERT) into the HPBECs. Microarrays of mRNA and DNA methylation were performed to compare the transcriptomes and DNA methylomes between these two types of cells. The results from the mRNA microarray revealed many genes whose expression changed upon cell immortalization. We identified signatures including global hypomethylation, perturbation of ECM-receptor interaction, focal adhesion, and PI3K-Akt pathways associated with cell immortalization. Moreover, we revealed 155 differentiated methylation regions (DMRs) within the CpG islands (CGIs) of 42 genes and the perturbation of several key pathways that might be involved in HBE cell immortalization. Among these genes, the hypermethylation of the plasma glutamate carboxypeptidase (PGCP) gene appeared specifically in lung cancer tissues. The inhibition of PGCP expression by promoter hypermethylation was observed in both immortal HBETT cells and benzo[a]pyrene (Bap)-transformed HBE cells. In conclusion, these findings provide new insight into the epigenetic modifications that are critical in the transition and maintenance of cell immortalization.


Assuntos
Benzo(a)pireno/toxicidade , Brônquios/patologia , Carboxipeptidases/genética , Transformação Celular Neoplásica/genética , Metilação de DNA , Neoplasias Pulmonares/genética , Brônquios/citologia , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Linhagem Celular , Ilhas de CpG , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Regiões Promotoras Genéticas , Transdução de Sinais
17.
Biol Trace Elem Res ; 182(2): 257-264, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28689237

RESUMO

The objective of this study was to investigate the effects of different sources and levels of zinc (Zn) on growth performance, nutrient digestibility, serum biochemical parameters, and fur quality in growing-furring male mink. Animals in the control group were fed a basal diet with no Zn supplementation. Mink in the other nine treatments were fed the basal diet supplemented with Zn from either grade Zn sulfate (ZnSO4·7H2O), Zn glycinate (ZnGly), or Zn pectin oligosaccharides (ZnPOS) at concentrations of either 100, 300, or 900 mg Zn/kg dry matter. One hundred and fifty healthy 15-week-old male mink were randomly allocated to ten dietary treatments (n = 15/group) for a 60-day trial from mid-September to pelting in December. Mink in the Zn-POS groups had higher average daily gain than those in the control group (P < 0.05). Zn source slightly improved the feed/gain (P = 0.097). N retention was increased by Zn addition (P < 0.05). Mink supplemented with dietary Zn had higher (P < 0.05) pancreas Zn level than the control group. Fur length was greater (P < 0.05) in ZnGly and ZnPOS groups compared with the control. In addition, fur length and fur density increased (linear, P < 0.05) with Zn supplementation in the diet. In conclusion, our data show that dietary Zn addition improves growth performance by increasing nitrogen retention and fat digestibility in growing-furring mink and Z-POS is equally bioavailable to mink compared to ZnGly.


Assuntos
Pelo Animal/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Compostos de Zinco/farmacologia , Ração Animal/análise , Animais , Disponibilidade Biológica , Suplementos Nutricionais , Glicina/administração & dosagem , Glicina/análogos & derivados , Glicina/farmacocinética , Glicina/farmacologia , Masculino , Vison , Oligossacarídeos/administração & dosagem , Oligossacarídeos/farmacocinética , Oligossacarídeos/farmacologia , Pectinas/administração & dosagem , Pectinas/farmacocinética , Pectinas/farmacologia , Distribuição Aleatória , Fatores de Tempo , Compostos de Zinco/administração & dosagem , Compostos de Zinco/farmacocinética
18.
Mutat Res ; 803-805: 17-21, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28759748

RESUMO

We evaluated DNA damage levels of different categories of workers exposed to hazards inside electronics factories in Southern China. To find out the most dangerous risk factor, a cross-sectional study was conducted on a total of 584 exposed subjects and 138 controls in an electronics factory in Southern China, where the electronics industry is prevalent. The exposed hazards included isopropanol (IPO), lead, noise, video display terminals (VDT), lead in a high-temperature (high-temp) environment, and IPO in a high-temp environment. DNA damage detection was performed by the micro-whole blood comet assay using peripheral blood. DNA damage levels were estimated by percent tail DNA (%T). Linear regression models were used to test DNA damage differences between exposed groups and control group with adjustments for potential confounding factors. The level of DNA damage was more significant in both lead in a high-temp and IPO in a high-temp environment groups than in that of the controls (p<0.05). The differences remained significant after stratifying by smoking status (p<0.05). There were no significant differences between groups exposed to IPO, lead, noise, VDT environment and controls. In conclusion, we identified potential risk factors for DNA damage to electronics workers. Special attention should be paid to workers exposed to IPO and lead in a high-temp environment.


Assuntos
Dano ao DNA/efeitos dos fármacos , Substâncias Perigosas/toxicidade , Indústria Manufatureira , Exposição Ocupacional/efeitos adversos , 2-Propanol/toxicidade , Acetona/toxicidade , Adolescente , Adulto , Benzeno/toxicidade , China , Ensaio Cometa , Estudos Transversais , Feminino , Temperatura Alta , Humanos , Chumbo/toxicidade , Modelos Lineares , Masculino , Inquéritos e Questionários , Tolueno/toxicidade , Xilenos/toxicidade , Adulto Jovem
19.
Toxicology ; 385: 1-9, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28458013

RESUMO

Chronic exposure to aflatoxin B1 (AFB1) is linked to the development of hepatocellular carcinoma (HCC). To identify differentially methylated genes involved in AFB1-induced cell transformation, we analyzed DNA methylation patterns in immortal human hepatocyte L02 cells expressing an oncogenic H-Ras allele (L02R cells) and AFB1-transformed L02R (L02RT-AFB1) cells by performing genome-wide methylation profiling. We treated L02R cells with 0.3µM AFB1 weekly and observed a transformed phenotype at the 17th week post-treatment. The transformed cells (L02RT-AFB1) could grow in an anchorage independent fashion and form tumors in immunodeficient mice. qRT-PCR was performed to examine whether gene methylation led to a reduction in gene expression of methylated candidate genes. As a result, the expression of the following seven genes including JUNB, RUNX3, NAV1, CXCR4, RARRES1, INTS1, and POLL was down-regulated in transformed L02RT-AFB1 cells. The reduction of gene expression of these genes could be reversed by treatment of 5-azadeoxycytidine. The methylated CpG sites of RUNX3 genes were verified using bisulfite sequencing PCR (BSP) assay. Furthermore, a dynamic change in RUNX3 methylation was observed over the course of AFB1-induced cell transformation, which was corresponded to the alteration of gene expression and the extent of DNA damage. In vitro study showed that methylation of RUNX3 tended to abate in L02R cells treated with AFB1 for a short-term period of time. Notably, hypermethylation of RUNX3 appeared in 70% (14/20) of human hepatocellular carcinomas. Moreover, LINE-1 hypomethylation and dynamic changes of DNMTs, TETs and MeCP2 expression were also observed during AFB1-induced transformation. Taken together, these observations suggest that aberrant methylation of RUNX3 and LINE-1 might be involved in AFB1-induced carcinogenesis.


Assuntos
Carcinoma Hepatocelular/genética , Transformação Celular Neoplásica/genética , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Neoplasias Hepáticas/genética , Adulto , Aflatoxina B1 , Carcinoma Hepatocelular/metabolismo , Linhagem Celular , Ensaio Cometa , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Metilação de DNA , Desoxirribonuclease I/genética , Feminino , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Pessoa de Meia-Idade
20.
Environ Pollut ; 225: 93-103, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28359976

RESUMO

Long term exposure to polycyclic aromatic hydrocarbons (PAHs) is associated with the increasing risk of lung cancer. To identify differentially hypermethylated genes associated with PAHs-induced carcinogenicity, we performed genome-wide DNA methylation analysis in 20 µM benzo(a)pyrene (BaP)-transformed human bronchial epithelial (HBE) cells at different stages of cell transformation. Several methylated genes (CNGA4, FLT1, GAREM1, SFMBT2, TRIM36) were differentially hypermethylated and their mRNA was suppressed in cells at both pre-transformed and transformed stages. Similar results were observed in HBE cells transformed by 20 µg/mL coke oven emissions (COEs) mixture collected from a coking manufacturing facility. In particular, hypermethylation of TRIM36 and suppression of TRIM36 expression were gradually enhanced over the time of COEs treatment. We developed bisulfite pyrosequencing assay and assessed TRIM36 methylation quantitatively. We found that hypermethylation of TRIM36 and reduced gene expression was prevalent in several types of human cancers. TRIM36 hypermethylation appeared in 90.0% (23/30) of Non-Small Cell Lung Cancer (NSCLCs) tissues compared to their paired adjacent tissues with an average increase of 1.32 fold. Furthermore, an increased methylation rate (5.90% v.s 7.38%) and reduced levels of TRIM36 mRNA were found in peripheral lymphocytes (PBLCs) of 151 COEs-exposed workers. In all subjects, TRIM36 hypermethylation was positively correlated with the level of urinary 1-hydroxypyrene (P < 0.001), an internal exposure marker of PAHs, and the DNA damage (P = 0.013). These findings suggest that aberrant hypermethylation of TRIM36 might be involved in the acquisition of malignant phenotype and could be served as a biomarker for risk assessment of PAHs exposure.


Assuntos
Poluentes Atmosféricos/toxicidade , Proteínas de Transporte/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Benzo(a)pireno/análise , Biomarcadores/metabolismo , Transformação Celular Neoplásica/induzido quimicamente , Coque , Dano ao DNA , Metilação de DNA , Humanos , Exposição Ocupacional/análise , Pirenos/urina , Sulfitos
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