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1.
Brain Cogn ; 140: 105526, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32007788

RESUMO

OBJECTIVE: Pregnancy causes many changes in our body and some of them may affect our ability of learning and memory. We examined the cerebral cortical volume of brain during pregnancy and measured changes in the brain electrical activity and cerebral blood flow. METHOD: 35 women (20 normal full-term primigravida and 15 non-pregnant women) received the Electroencephalography (EEG) and Transcranial Doppler ultrasonography (TCD). 8 non-pregnant women and 9 primigravida after vaginal delivery underwent brain magnetic resonance imaging (MRI) voluntarily within 24 h. RESULTS: Compared with the non-pregnant, changes were shown by EEG through electrodes of T5, Pz, Cz, T6, F3 and F8. The results displayed increased activity in the central parietal area of pregnant women, while that in the temporoparietal junction decreased. The result of TCD revealed that pulsation index (PI) values of left and right internal and external carotid arteries were asymmetrical, but they all decreased in pregnancy. Atrophy of cortical volume had been found in many brain functional areas of pregnant women. The percentage of atrophy varied between 6.76% and 13.17%. CONCLUSION: Atrophy of cerebral cortex, changes in cerebral blood flow and neuron electrophysiology may be the physiological basis of the emotional, cognitive changes in pregnant women.

2.
Biomed Pharmacother ; 124: 109883, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32004938

RESUMO

Intestinal mucositis causes great suffering to cancer patients who undergo chemotherapy and radiotherapy. Owing to the uncertain side effects of anticancer drugs to attenuate patients' intestinal mucositis, many studies focused on traditional Chinese medicine (TCM). Patchouli alcohol (PA) is an active compound extracted from Pogostemon cablin, and has potent gastrointestinal protective effect. However, whether PA has an effect on intestinal mucositis is still unknown. Therefore, we established a rat model of intestinal mucositis via intraperitoneal injection of 5-fluorouracil, and intragastrically administrated PA (10, 20, and 40 mg/kg) to evaluate the effect of PA on intestinal mucositis. The routine observation (body weight, food intake, and diarrhea) in rats was used to detect whether PA had an effect on intestinal mucositis. Levels of inflammatory cytokines (TNF-α, IL-1ß, IL-6, IL-10, and MPO), mucosal barrier proteins (zonula occludens -1 (ZO-1), claudin-1, occludin, myosin light chain (MLC), and mucin-2) and intestinal microbiota were determined to elucidate the underlying mechanism of PA action on intestinal mucositis in rats. The results showed that PA could effectively improve body weight, food intake, and diarrhea in intestinal mucositis rats, preliminary confirming PA efficacy. Further experiments revealed that PA not only decreased the levels of TNF-α, IL-1ß, IL-6, and MPO but also increased the level of IL-10 significantly. In addition, the expression of mucosal barrier proteins and microbiota community were also improved after PA treatment in diseased rats. Hence, PA may prevent the development and progression of intestinal mucositis by improving inflammation, protecting mucosal barrier, and regulating intestinal microbiota.

3.
Planta Med ; 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31975362

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases worldwide. Nevertheless, no first-line therapy exists. Hepatic steatosis is the earliest stage of NAFLD, which is characterized by an accumulation of hepatic lipids. Patchouli oil (PO), which is isolated from the well-known Chinese herb named Pogostemon cablin (Blanco) Benth. (Lamiaceae), inhibits hepatic lipid accumulation effectively. However, its potential ability for the treatment of NAFLD had not been reported before. Thus, the objective of this study was to investigate the effectiveness of PO against hepatic steatosis and its underlying mechanisms. We used a high fat diet (HFD)-induced hepatic steatosis model of rats to estimate the effect of PO against NAFLD. Hematoxylin-eosin and oil red O staining were used to analyze the hepatic histopathological changes. ELISA, RT-qPCR, and Western blotting analysis were applied to evaluate the parameters for hepatic steatosis. Our results showed that PO significantly attenuated the lipid profiles and the serum enzymes, evidenced by quantitative and histopathological analyses. It also markedly down-regulated the expression of sterol regulatory element-binding protein 1 (SREPB-1c) with its downstream factors in de novo lipogenesis. And, likewise, in lipid export by very low-density lipoproteins (VLDL), related molecules were dramatically improved. Furthermore, PO observably normalized the aberrant peroxisome proliferator-activated receptor α (PPAR-α) signal in fatty acids oxidation. In conclusion, PO exerted a preventing effect against HFD-induced steatosis and might be due to decrease de novo lipogenesis, promote export of lipids, as well as owing to improve fatty acids oxidation.

4.
J Ethnopharmacol ; 250: 112519, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31883475

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Pogostemon cablin, commonly named "Guang-Huo-Xiang" in China, has long been renowned for its ability to dispel dampness and regulate gastrointestinal functions. Patchouli oil (P.oil), the major active fraction of Pogostemon cablin, has been traditionally used as the principal component of Chinese medicinal formulae to treat exterior syndrome and diarrhea. However, the effects of P.oil in treating 5-fluorouracil (5-FU)-induced intestinal mucositis have not yet been reported. AIM OF THE STUDY: To investigate the protective effects of P.oil against 5-FU-induced intestinal mucositis and the mechanisms underlying these effects. MATERIALS AND METHODS: Sprague-Dawley rats were intraperitoneally injected with 5-FU (30 mg/kg) to establish an intestinal mucositis model. Meanwhile, rats with intestinal mucositis were orally administered with P.oil (25, 50, and 100 mg/kg). Histological analysis, ELISA (for detecting inflammatory cytokines and aquaporins), immunohistochemistry analysis (for examining caspases), qRT-PCR analysis (for assessment tight junctions), and western blotting analysis (for the assessment of TLR2/TLR4-MyD88 and VIP-cAMP-PKA signaling pathway-related proteins) were performed to estimate the protective effects of P.oil against intestinal mucositis and the mechanisms underlying these effects. RESULTS: The histopathological assessment preliminarily exhibited that P.oil alleviated the 5-FU-induced damage to the intestinal structure. After P.oil administration, the elevation of the expression of cytokines (TNF-α, IFN-γ, and IL-13) decreased markedly and the activation of NF-κB and MAPK signaling was significantly inhibited. P.oil also increased the mRNA expression of ZO-1 and Occludin, thereby stabilizing intestinal barrier. In addition, P.oil decreased the expressions of caspase-8, caspase-3, and Bax, and increased the expression of Bcl-2, thereby reducing the apoptosis of the intestinal mucosa. These results were closely related to the regulation of the TLR2/TLR4-MyD88 signaling pathway. It has been indicated that P.oil possibly protected the intestinal barrier by reducing inflammation and apoptosis. Furthermore, this study showed that P.oil inhibited the abnormal expression of AQP3, AQP7, and AQP11 by regulating the VIP-cAMP-PKA signaling pathway. Furthermore, it restored the intestinal water absorption, thereby alleviating diarrhea. CONCLUSIONS: P.oil ameliorated 5-FU-induced intestinal mucositis in rats via protecting intestinal barrier and regulating water transport.

5.
Front Pharmacol ; 10: 1134, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632274

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is currently the most common chronic hepatic disorder worldwide. The earliest stage of NAFLD is simple steatosis, which is characterized by the accumulation of triglycerides in hepatocytes. Inhibition of steatosis is a potential treatment for NAFLD. Patchouli alcohol (PA) is an active component of Pogostemon cablin (Blanco) Benth. (Labiatae), which is a medicinal food in Asia countries and proved to possess hepatoprotective effect. This research aimed to investigate the effectiveness of PA against high fat diet (HFD)-induced hepatic steatosis in rats. In this study, male Sprague Dawley rats were fed a HFD for 4 weeks to induce NAFLD. Oral administration with PA significantly reduced pathological severity of steatosis in HFD-fed rats. It was associated with suppressing endoplasmic reticulum (ER) stress and regulating very low-density lipoprotein (VLDL) metabolism. Our data showed that PA treatment effectively attenuated ER stress by inhibiting the activation of protein kinase-like ER kinase (PERK), inositol-requiring transmembrane kinase/endoribonuclease 1 (IRE1), and activating transcription factor 6 (ATF6). Moreover, PA decreased hepatic VLDL uptake by suppressing very low-density lipoprotein receptor (VLDLR) expression. It also restored VLDL synthesis and export by increasing apolipoprotein B100 (apoB 100) secretion and microsomal triglyceride-transfer protein (MTP) activity. Taken together, PA exerted a protective effect on the treatment of NAFLD in HFD-fed rats and may be potential therapeutic agent acting on hepatic steatosis.

6.
Bioresour Technol ; 293: 122032, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31491647

RESUMO

Two de-lignified cellulose of loofah sponge and sawdust were applied in two ways to enhance the lipid production from oleaginous yeast using acetic acid. When 30 g/L of acetic acid was used as a carbon source, direct addition of de-lignified loofah sponge or sawdust increased the extracellular lipid content to 33.94% and 53.25%, respectively. The latter reduced the energy input of lipid extraction process from 0.86 to 0.57 GJ per ton of biodiesel production. To relieve the inhibition caused by 40 g/L acetic acid, immobilization of oleaginous yeast on de-lignified sawdust increased the lipid concentration and yield from 3.83 g/L, 0.18 g/g C to 7.15 g/L, 0.20 g/g C, respectively. These improvements occurred due to the cell-immobilized sawdust which play an important role in the loading of cells and adsorption of acetic acid. Immobilized cultivation also increased the fatty acid proportion of C18:1, thereby improving biodiesel performance.


Assuntos
Ácido Acético , Celulose , Biocombustíveis , Ácidos Graxos , Lipídeos
7.
Artigo em Inglês | MEDLINE | ID: mdl-31380297

RESUMO

The consumption of probiotics and fermented foods has been very popular in recent decades. The primary aim of our study was to evaluate the effect of probiotics on the gut microbiota and the changes in inflammatory cytokines after an average of 6.7 weeks of probiotic administration among normal pregnant women. Thirty-two healthy pregnant women at 32 weeks of gestation were recruited and divided into two groups. The probiotic group ingested combined probiotics until after birth. The base characteristics of the probiotics and control groups showed no significant differences. The structure of the fecal microbiota at the genus level varied during the third trimester, and administration of probiotics had no influence on the composition of the fecal microbiota however, many highly abundant taxa and core microbiota at the genus level changed in the probiotic group when compared to the control group. The analysis of cytokines showed that IL-5, IL-6, TNF-α, and GM-CSF had equal levels between the baseline and control groups but were significantly increased after probiotic administration (baseline = control < probiotics). Additionally, levels of IL-1ß, IL-2, IL-12, and IFN-γ significantly increased among the three groups (baseline < control < probiotics). This result demonstrated that probiotics helped to shift the anti-inflammatory state to a pro-inflammatory state. The correlation analysis outcome suggested that the relationship between the microbiota and the cytokines was not strain-dependent. The gut microbiota varied during the third trimester. The probiotics demonstrated immunomodulation effects that helped to switch over to a pro-inflammatory immune state in the third trimester, which was important for labor.

8.
J Ethnopharmacol ; 232: 11-20, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30529424

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: In traditional Chinese medicine, supplementing Qi and strengthening body resistance are an important principle of anticancer treatment. Panax ginseng C.A.Mey. (ginseng) and Astragalus membranaceus Bunge (astragalus) are the representative herbs for this therapeutic principle. AIM OF THE STUDY: This study aims to explore the effect of the water extract of ginseng and astragalus (WEGA) on regulating macrophage polarization and mediating anticancer in the tumor microenvironment. MATERIALS AND METHODS: A549 cells were cultured in tumor-associated macrophage (TAM) supernatant with various concentrations of WEGA (0, 5, 10, 20 mg/mL). A549 cell proliferation was determined through methyl thiazole tetrazolium (MTT) assay and real-time cell analysis (RTCA), respectively. In vivo experiments were performed with a Lewis lung cancer (LLC) xenograft mouse model. Forty-eight mice were divided into six groups and treated with saline, WEGA, or cis-diamine dichloro platinum (DDP) with dosage of WEGA (0, 30, 60, 120 mg/kg body weight/day). The different groups were administered with drugs via oral or intraperitoneal injection once a day for 21 consecutive days. Tumor inhibition rate, spleen index, thymus index, cytokine, protein, and mRNA expression levels were detected in mice. RESULTS: In a co-culture system, WEGA remarkably inhibited A549 cell proliferation, promoted the expression of M1 macrophage markers and inhibited M2 TAMs markers. Therefore, WEGA affected the biological behavior of cancer cells by regulating the expression of some markers relevant to macrophage polarization. In addition, the group of WEGA and DDP chemotherapy effectively inhibited the transplanted tumor growth in mice and improved weight loss and immunosuppressive with the cisplatin inducing. CONCLUSIONS: This study provides mechanistic insights into the anticancer effect of WEGA through the regulation of macrophage polarization and highlights that WEGA could be a novel option for integrative cancer therapies.


Assuntos
Antineoplásicos , Astrágalo (Planta) , Carcinoma Pulmonar de Lewis , Neoplasias Pulmonares , Macrófagos/efeitos dos fármacos , Panax , Extratos Vegetais , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Pulmonar de Lewis/patologia , Linhagem Celular Tumoral , Polaridade Celular/efeitos dos fármacos , Cisplatino/uso terapêutico , Citocinas/imunologia , Sinergismo Farmacológico , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Macrófagos/fisiologia , Camundongos Endogâmicos C57BL , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Solventes/química , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/fisiologia , Água/química
9.
Prev Chronic Dis ; 15: E156, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30576278

RESUMO

INTRODUCTION: As lifestyles have increasingly become westernized in China, public health strategies have increasingly focused on cancer prevention. The objective of this study was to describe trends in colorectal cancer (CRC) mortality and the age, period, and cohort effects of CRC mortality in urban and rural China from 2000 to 2015. METHODS: We collected CRC mortality data from the China Health Statistics Yearbook. We used joinpoint regression analysis to estimate the slope of mortality trends. We then used the age-period-cohort (APC) model with intrinsic estimator to estimate the age, period, and cohort effects of CRC mortality. RESULTS: CRC mortality was higher in urban areas than in rural areas, and the average annual percentage change was also larger in urban areas (4.1%) than in rural areas (3.7%). CRC mortality risk was higher among older adults than among adults aged 20 to 24: the relative risk among adults aged 60 to 64 was 31.09 times higher in urban China and 11.46 times higher in rural China. CRC mortality risk increased with period: compared with period 2000, the relative risk was 1.01 in period 2005, 1.36 in period 2010, and 1.42 in period 2015 in urban China and 1.12 in period 2005, 1.24 in period 2010, and 1.69 in period 2015 in rural China. More recent cohorts had lower CRC mortality risk: compared with the cohort born during 1920-1924, the relative risk of cohort 1950-1954 was 0.70 in urban China and 0.69 in rural China. CONCLUSION: More interventions to reduce the burden of CRC should be conducted, and it is more necessary for older people and urban residents to adopt a healthy lifestyle in China.


Assuntos
Neoplasias Colorretais/mortalidade , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Vigilância da População , Prevalência , Análise de Regressão , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Adulto Jovem
10.
Bioresour Technol ; 262: 9-14, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29689440

RESUMO

Low concentrations of acetic acid were used as carbon source to cultivate Cryptococcus curvatus MUCL 29819 for lipid production under high content of ammonia. Phosphorus limitation combined with initial pH regulation (pH = 6) weakened inhibition of free ammonia and promoted lipid accumulation. In batch cultivation, the produced lipid content and yield was 30.3% and 0.92 g/L, higher than those under unlimited condition (18.3% and 0.64 g/L). The content of monounsaturated fatty acid also increased from 37.3% (unlimited condition) to 45.8% (phosphorus-limited condition). During sequencing batch cultivation (SBC), the lipid content reached up to 51.02% under phosphorus-limited condition while only 31.88% under unlimited condition, which can be explained by the higher conversion efficiency of the carbon source to lipid. The total energy consumption including lipid extraction, transesterification and purification was 7.47 and 8.33 GJ under phosphorus-limited and unlimited condition, respectively.


Assuntos
Cryptococcus , Lipídeos/análise , Fósforo , Amônia , Técnicas de Cultura Celular por Lotes , Biomassa
11.
Bioresour Technol ; 247: 395-401, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28961445

RESUMO

Oleaginous yeast Cryptococcus curvatus MUCL 29819, an acid-tolerant lipid producer, was tested to spill lipids extracellularly using different concentrations of acetic acid as carbon source. Extracellular lipids were released when the yeast was cultured with acetic acid exceeding 20g/L. The highest production of lipid (5.01g/L) was obtained when the yeast was cultured with 40g/L acetic acid. When the yeast was cultivated with moderate concentration (20g/L) of acetic acid, lipid production was further increased by 49.6% through preculture with 40g/L acetic acid as stimulant. When applying high concentration (40g/L) of acetic acid as carbon source in sequencing batch cultivation, extracellular lipids accounted up to 50.5% in the last cycle and the extracellular lipids reached 5.43g/L through the whole process. This study provides an effective strategy to enhance extracellular lipid production and facilitate the recovery of microbial lipids.


Assuntos
Ácido Acético , Lipídeos , Técnicas de Cultura Celular por Lotes , Biomassa , Carbono , Cryptococcus
12.
Sci Rep ; 6: 31088, 2016 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-27501986

RESUMO

Somatic cell nuclear transfer (SCNT) provides an excellent model for studying epigenomic reprogramming during mammalian development. We mapped the whole genome and whole methylome for potential anomalies of mutations or epimutations in SCNT-generated dogs with XY chromosomal sex but complete gonadal dysgenesis, which is classified as 78, XY disorder of sex development (DSD). Whole genome sequencing revealed no potential genomic variations that could explain the pathogenesis of DSD. However, extensive but stochastic anomalies of genome-wide DNA methylation were discovered in these SCNT DSD dogs. Persistent abnormal hypermethylation of the SRY gene was observed together with its down-regulated mRNA and protein expression. Failure of SRY expression due to hypermethylation was further correlated with silencing of a serial of testis determining genes, including SOX9, SF1, SOX8, AMH and DMRT1 in an early embryonic development stage at E34 in the XY(DSD) gonad, and high activation of the female specific genes, including FOXL2, RSPO1, CYP19A1, WNT4, ERα and ERß, after one postnatal year in the ovotestis. Our results demonstrate that incomplete demethylation on the SRY gene is the driving cause of XY(DSD) in these XY DSD dogs, indicating a central role of epigenetic regulation in sex determination.


Assuntos
Metilação de DNA , Transtornos do Desenvolvimento Sexual/genética , Técnicas de Transferência Nuclear/efeitos adversos , Proteína da Região Y Determinante do Sexo/genética , Animais , Clonagem de Organismos , Modelos Animais de Doenças , Transtornos do Desenvolvimento Sexual/etiologia , Transtornos do Desenvolvimento Sexual/metabolismo , Cães , Epigênese Genética , Feminino , Disgenesia Gonadal/etiologia , Disgenesia Gonadal/genética , Disgenesia Gonadal/metabolismo , Masculino , Gravidez , Processos de Determinação Sexual , Processos Estocásticos , Testículo/embriologia , Testículo/metabolismo , Cromossomo Y/genética
13.
Sci Rep ; 6: 31826, 2016 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-27546520

RESUMO

Recently, 5-hydroxymethylcytosine patterning across the tumor genome was considered as a hallmark of cancer development and progression. However, locus-specific difference of hydroxymethylation between colorectal cancer and normal tissue is unknown. In this study, we performed a newly developed method, HMST-seq, to profile 726 aberrant methylated loci and 689 aberrant hydroxymethylated loci synchronously in genome wide of colorectal cancers, majority of which presented higher methylation or lower hydroxymethylationin than in normal group. Besides, abnormal hydroxymethylated modification was more frequently occur at proximal regions close to TSSs and TSSs regions than abnormal methylation. Subsequently, we screened four genes (ALOX15, GHRHR, TFPI2 and TKTL1) with aberrant methylation and aberrant hydroxymethylation at some genome position by functional enrichment analysis as candidate genes associated with colorectal cancer. Our results may allow us to select differentially epigenetically modified target genes implicated in colorectal cancer tumorigenesis.


Assuntos
5-Metilcitosina/análogos & derivados , Neoplasias Colorretais/genética , Metilação de DNA , Redes Reguladoras de Genes , 5-Metilcitosina/química , Araquidonato 15-Lipoxigenase/genética , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Glicoproteínas/genética , Humanos , Análise de Sequência de DNA , Transcetolase/genética
14.
Sci Rep ; 6: 20181, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26830322

RESUMO

Intrauterine growth restriction (IUGR) affects the foetus and has a number of pathological consequences throughout life. Recent work has indicated that variations in DNA methylation might cause placental dysfunction, which may be associated with adverse pregnancy complications. Here, we investigated the promoter methylomes of placental shares from seven monochorionic (MC) twins with selective intrauterine growth restriction (sIUGR) using the healthy twin as an ideal control. Our work demonstrated that the IUGR placental shares harboured a distinct DNA hypomethylation pattern and that the methylation variations preferentially occurred in CpG island shores or non-CpG island promoters. The differentially methylated promoters could significantly separate the IUGR placental shares from the healthy ones. Ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) further confirmed the genome-wide DNA hypomethylation and the lower level of hydroxymethylation statuses in the IUGR placental shares. The methylation variations of the LRAT and SLC19A1 promoters, which are involved in vitamin A metabolism and folate transportation, respectively, and the EFS promoter were further validated in an additional 12 pairs of MC twins with sIUGR. Although the expressions of LRAT, SLC19A1 and EFS were not affected, we still speculated that DNA methylation and hydroxymethylation might serve a functional role during in utero foetal development.


Assuntos
Metilação de DNA/genética , Retardo do Crescimento Fetal/genética , Placenta/metabolismo , Regiões Promotoras Genéticas , Gêmeos Monozigóticos/genética , Feminino , Feto/patologia , Regulação da Expressão Gênica , Impressão Genômica , Humanos , Gravidez , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Análise de Sequência de DNA , Transdução de Sinais/genética
15.
Epigenomics ; 7(1): 47-56, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25687465

RESUMO

AIM: To develop a whole-genome methylation sequencing method that fulfills the needs for studies using ultra-low-input DNA. MATERIALS & METHODS: The tagmentation-based whole-genome bisulfite sequencing (T-WGBS) technology is modified, enabling stable library construction with complexity from minimally 0.5 ng of initial genomic DNA, which equals less than 100 mammalian cells. RESULTS: We thoroughly assessed the performance of this T-WGBS method by sequencing the methylomes of a rice strain and pre-implantation embryos of rhesus monkey and compare to traditional WGBS approach, thereby demonstrating the efficacy of this new approach. CONCLUSION: This new approach is highly attractive for the complete methylome analysis of very few cells, for example, mammalian pre-implantation embryos, or tiny human biopsy specimens.


Assuntos
Metilação de DNA , Análise de Sequência de DNA/métodos , Animais , Genômica/métodos , Macaca mulatta , Oryza/genética , Sulfitos
16.
Genome Biol ; 15(12): 533, 2014 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-25517360

RESUMO

BACKGROUND: Differences in 5-hydroxymethylcytosine, 5hmC, distributions may complicate previous observations of abnormal cytosine methylation statuses that are used for the identification of new tumor suppressor gene candidates that are relevant to human hepatocarcinogenesis. The simultaneous detection of 5-methylcytosine and 5-hydroxymethylcytosine is likely to stimulate the discovery of aberrantly methylated genes with increased accuracy in human hepatocellular carcinoma. RESULTS: Here, we performed ultra-performance liquid chromatography/tandem mass spectrometry and single-base high-throughput sequencing, Hydroxymethylation and Methylation Sensitive Tag sequencing, HMST-seq, to synchronously measure these two modifications in human hepatocellular carcinoma samples. After identification of differentially methylated and hydroxymethylated genes in human hepatocellular carcinoma, we integrate DNA copy-number alterations, as determined using array-based comparative genomic hybridization data, with gene expression to identify genes that are potentially silenced by promoter hypermethylation. CONCLUSIONS: We report a high enrichment of genes with epigenetic aberrations in cancer signaling pathways. Six genes were selected as tumor suppressor gene candidates, among which, ECM1, ATF5 and EOMES are confirmed via siRNA experiments to have potential anti-cancer functions.


Assuntos
Fatores Ativadores da Transcrição/genética , Carcinoma Hepatocelular/genética , Metilação de DNA , Proteínas da Matriz Extracelular/genética , Neoplasias Hepáticas/genética , Proteínas com Domínio T/genética , 5-Metilcitosina/metabolismo , Linhagem Celular Tumoral , Hibridização Genômica Comparativa , Citosina/análogos & derivados , Citosina/metabolismo , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Análise de Sequência de DNA/métodos
17.
Genomics ; 103(2-3): 204-10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24407023

RESUMO

The model describing that aberrant CpG island (CGI) methylation leads to repression of tumour suppressor genes in cancers has been influential, but it remains unclear how such aberrancy is induced. Recent studies provided clues indicating that promoter hypermethylation in cancers might be associated with PRC target genes. Here, we used ChIP-BS-seq to examine methylation of the DNA fragments precipitated by the antibodies to both H3K27me3 and H3K4me3 histone modifications. We showed that, for a set of genes highly enriched with H3K27me3 both in cancer and normal cells, CGI promoters were aberrantly hypermethylated only in cancer cells in comparison with normal cells. In contrast, such aberrant CGI hypermethylation in cancer promoters that were deficient of H3K27me3 was not notable. Furthermore, we confirmed that these genes were consistently hypermethylated in TCGA primary cancer cells. These works support the association between H3K27me3 and DNA methylation marks for specific cancer genes and will spur future work on combined histone and DNA methylation that could define cancer's epigenetic abnormalities.


Assuntos
Ilhas de CpG , Metilação de DNA , DNA de Neoplasias , Histonas , Proteínas de Neoplasias , Neoplasias , Regiões Promotoras Genéticas , Análise de Sequência de DNA , Linhagem Celular Tumoral , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/metabolismo
18.
Nanotechnology ; 24(49): 495702, 2013 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-24231132

RESUMO

Understanding the interactions between graphene and biomolecules is of fundamental relevance to the area of nanobiotechnology. Herein, we take l-cysteine as the probe biomolecule and investigate its adsorption on pristine graphene and B-, N-, Al-, Ni-, Ga-, Pd-doped graphene using density functional theory calculations. Three kinds of upright adsorption configurations, via unprotonated functional groups (-SH, -NH2, -COOH), are considered. The calculations reveal pristine graphene physically adsorbs l-cysteine. N-doped graphene shows physisorption towards the S-end and N-end l-cysteine, and chemisorption towards the O-end radical. Strong chemisorption, with site-specific preference, occurs on Al-, Ni-, Ga- and Pd-doped graphene, accompanied by severe structural changes. Spin polarization with an unusual mirror symmetry on Ni- and Pd-doped graphene is induced by chemisorption of unprotonated l-cysteine, except for O-end adsorption on Pd-doped graphene. The magnetization arises mainly from spin polarization of the C 2pz orbital, with a minor magnetism located on Ni or Pd. The influence of van der Waals forces is also evaluated. A thorough analysis of the adsorption stability and magnetism of these systems would be beneficial to facilitate applications in graphene-based biosensing, biomolecule immobilization, magnetic bio-separation and other fields in bionanotechnology.


Assuntos
Cisteína/química , Grafite/química , Adsorção , Alumínio/química , Biotecnologia , Simulação por Computador , Radicais Livres , Gálio/química , Magnetismo , Nanotecnologia , Níquel/química , Paládio/química , Propriedades de Superfície
19.
Epigenetics ; 8(4): 421-30, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23502161

RESUMO

5-methylcytosine (5-mC) can be oxidized to 5-hydroxymethylcytosine (5-hmC). Genome-wide profiling of 5-hmC thus far indicates 5-hmC may not only be an intermediate form of DNA demethylation but could also constitute an epigenetic mark per se. Here we describe a cost-effective and selective method to detect both the hydroxymethylation and methylation status of cytosines in a subset of cytosines in the human genome. This method involves the selective glucosylation of 5-hmC residues, short-Sequence tag generation and high-throughput sequencing. We tested this method by screening H9 human embryonic stem cells and their differentiated embroid body cells, and found that differential hydroxymethylation preferentially occurs in bivalent genes during cellular differentiation. Especially, our results support hydroxymethylation can regulate key transcription regulators with bivalent marks through demethylation and affect cellular decision on choosing active or inactive state of these genes upon cellular differentiation. Future application of this technology would enable us to uncover the status of methylation and hydroxymethylation in dynamic biological processes and disease development in multiple biological samples.


Assuntos
5-Metilcitosina/metabolismo , Diferenciação Celular/genética , Citosina/análogos & derivados , Metilação de DNA/fisiologia , Células-Tronco Embrionárias/citologia , Ensaios de Triagem em Larga Escala/métodos , Animais , Células Cultivadas , Citosina/metabolismo , Corpos Embrioides/citologia , Células-Tronco Embrionárias/metabolismo , Humanos , Camundongos , Análise de Sequência de DNA/métodos
20.
BMC Genomics ; 14: 11, 2013 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-23324053

RESUMO

BACKGROUND: Reduced representation bisulfite sequencing (RRBS) was developed to measure DNA methylation of high-CG regions at single base-pair resolution, and has been widely used because of its minimal DNA requirements and cost efficacy; however, the CpG coverage of genomic regions is restricted and important regions with low-CG will be ignored in DNA methylation profiling. This method could be improved to generate a more comprehensive representation. RESULTS: Based on in silico simulation of enzyme digestion of human and mouse genomes, we have optimized the current single-enzyme RRBS by applying double enzyme digestion in the library construction to interrogate more representative regions. CpG coverage of genomic regions was considerably increased in both high-CG and low-CG regions using the double-enzyme RRBS method, leading to more accurate detection of their average methylation levels and identification of differential methylation regions between samples. We also applied this double-enzyme RRBS method to comprehensively analyze the CpG methylation profiles of two colorectal cancer cell lines. CONCLUSION: The double-enzyme RRBS increases the CpG coverage of genomic regions considerably over the previous single-enzyme RRBS method, leading to more accurate detection of their average methylation levels. It will facilitate genome-wide DNA methylation studies in multiple and complex clinical samples.


Assuntos
Ilhas de CpG/genética , Metilação de DNA/efeitos dos fármacos , Genômica/métodos , Mapeamento por Restrição/métodos , Análise de Sequência de DNA/métodos , Sulfitos/farmacologia , Animais , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/deficiência , DNA (Citosina-5-)-Metiltransferases/genética , Técnicas de Inativação de Genes , Células HCT116 , Humanos , Camundongos
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