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1.
J Surg Oncol ; 120(8): 1427-1435, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31729037

RESUMO

BACKGROUND AND OBJECTIVES: Mucinous adenocarcinoma is a distinct subtype of colorectal cancer (CRC) with a worse prognosis when compared with non-mucinous adenocarcinoma. The aim of this study was to compare somatic mutations and copy number alteration (CNA) between mucinous and non-mucinous CRC. METHODS: Data from The Cancer Genome Atlas-colon adenocarcinoma and rectum adenocarcinoma projects were utilized. Mucinous and non-mucinous CRC were compared with regard to microsatellite status, overall mutation rate, the most frequently mutated genes, mutations in genes coding for mismatch repair (MMR) proteins and genes coding for mucin glycoproteins. CNA analysis and pathway analysis was undertaken. RESULTS: Mucinous CRC was more likely to be microsatellite instability-high (MSI-H) and hypermutated. When corrected for microsatellite status the single-nucleotide variation and insertion-deletion rate was similar between the two cohorts. Mucinous adenocarcinoma was more likely to have mutations in genes coding for MMR proteins and mucin glycoproteins. Pathway analysis revealed further differences between the two histological subtypes in the cell cycle, RTK-RAS, transforming growth factor-ß, and TP53 pathways. CONCLUSIONS: Mucinous CRC has some distinct genomic aberrations when compared with non-mucinous adenocarcinoma, many of which are driven by the increased frequency of MSI-H tumors. These genomic aberrations may play an important part in the difference seen in response to treatment and prognosis in mucinous adenocarcinoma.


Assuntos
Adenocarcinoma Mucinoso/genética , Adenocarcinoma/genética , Neoplasias do Colo/genética , Genômica , Neoplasias Retais/genética , Adenocarcinoma/patologia , Adenocarcinoma Mucinoso/patologia , Estudos de Coortes , Neoplasias do Colo/patologia , Variações do Número de Cópias de DNA , Proteínas de Ligação a DNA/genética , Conjuntos de Dados como Assunto , Regulação Neoplásica da Expressão Gênica , Humanos , Mutação INDEL , Instabilidade de Microssatélites , Mucinas/genética , Mutação , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Retais/patologia , Proteína Smad4/genética , Fator de Crescimento Transformador beta/genética , Proteína Supressora de Tumor p53/genética
2.
J Dairy Sci ; 102(12): 10760-10771, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31521344

RESUMO

Over the past decades, several studies investigated the health-promoting functions of milk peptides. However, to date many hurdles still exist regarding the widespread use of milk-derived bioactive peptides, as they may be degraded during gastrointestinal digestion. Thus, the aim of our study was to in vitro digest intact whey protein isolate (WPI) and casein proteins (CNP), mimicking in vivo digestion, to investigate their bioactive effects and to identify the potential peptides involved. Whey protein isolate and CNP were digested using a pepsin-pancreatin protocol and ultra-filtered (3-kDa cutoff membrane). A permeate (<3 kDa) and a retentate (>3 kDa) were obtained. Soy protein was included as a control (CTR). Angiotensin-1-converting enzyme inhibitory (ACE1-I) and antioxidant activity (AOX) were assessed and compared with those observed in undigested proteins and CTR. Furthermore, the permeate was characterized by nano-liquid chromatography electrospray ionization tandem mass spectrometry (LC-nano ESI MS/MS) using a shotgun peptidomic approach, and retentate was further digested with trypsin and analyzed by MS using a shotgun proteomic approach to identify potentially bioactive peptides. Further, the effects of WPI, CNP, and CTR retentate on cell metabolic activity and on mucus production (MUC5AC and MUC2 gene expression) were assessed in intestinal goblet HT29-MTX-E12 cells. Results showed that WPI permeate induced a significant ACE1-I inhibitory effect [49.2 ± 0.64% (SEM)] compared with undigested WPI, CNP permeate, and retentate or CTR permeate (10.40 ± 1.07%). A significant increase in AOX (1.58 ± 0.04 and 1.61 ± 0.02 µmol of trolox AOX equivalents per mg of protein, respectively) upon digestion was found in WPI. Potentially bioactive peptides associated with ACE1-I and antihypertensive effects were identified in WPI permeate and CNP retentate. At specific concentrations, WPI, CNP, and CTR retentate were able to stimulate metabolic activity in HT29-MTX-E12 cells. Expression of MUC5AC was increased by CNP retentate and unaltered by WPI retentate; MUC2 expression was significantly increased by 0.33 mg/g of CNP and reduced by 1.33 mg/g of CNP. Our results confirm that milk proteins may be rich sources of bioactive compounds, with the greatest beneficial potential of CNP at the intestinal goblet cell level.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/química , Antioxidantes/metabolismo , Digestão , Proteínas do Leite/metabolismo , Mucinas/genética , Peptidil Dipeptidase A/metabolismo , Animais , Caseínas/metabolismo , Cromatografia Líquida , Expressão Gênica , Células HT29 , Humanos , Leite/metabolismo , Proteínas de Soja/metabolismo , Espectrometria de Massas em Tandem , Soro do Leite/metabolismo
3.
Pharm Res ; 36(11): 162, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529336

RESUMO

PURPOSE: Mucins are the principal glycoproteins in mucus and have been implicated in the limitation of intestinal drug absorption; however, the contribution of these molecules to intestinal drug absorption remains unclear. In this study, the relationship between the effect of the mucus layer on intestinal drug permeation and mucin distribution in different parts of the rat gastrointestinal tract was evaluated. METHODS: The intestinal permeability of various lipophilic drugs in rat small intestine was evaluated using the in vitro sac method. The expression profiles of mucin mRNA and proteins were evaluated by quantitative real-time RT-PCR and western blotting, respectively. RESULTS: The intestinal permeability of griseofulvin and antipyrine was enhanced by dithiothreitol (DTT) treatment in the proximal small intestine, such as duodenum and jejunum, but not in the distal regions. The mRNA expression analysis of rat mucin genes revealed that the intestinal expression of Muc5ac was considerably higher in the duodenum, whereas that of Muc1, Muc2, and Muc3A was gradually increased toward the lower intestine. In addition, Muc5ac protein was detected only in the luminal fluids from the proximal small intestine after DTT treatment. CONCLUSIONS: Mucus limits the intestinal permeation of lipophilic drugs in the rat proximal small intestine, in which Muc5ac may be involved.


Assuntos
Antipirina/farmacologia , Griseofulvina/farmacologia , Intestino Delgado/metabolismo , Lipossomos , Glicoproteínas de Membrana/metabolismo , Mucinas/metabolismo , Animais , Antipirina/metabolismo , Composição de Medicamentos , Griseofulvina/metabolismo , Absorção Intestinal , Mucinas/genética , Ratos
4.
BMC Infect Dis ; 19(1): 622, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31307416

RESUMO

BACKGROUND: Cell-surface mucins are expressed in apical epithelial cells of the respiratory tract, and contribute a crucial part of the innate immune system. Despite anti-inflammatory or antiviral functions being revealed for certain cell-surface mucins such as MUC1, the roles of other mucins are still poorly understood, especially in viral infections. METHODS: To further identify mucins significant in influenza infection, we screened the expression of mucins in human nasal epithelial cells infected by H3N2 influenza A virus. RESULTS: We found that the expression of MUC15 was significantly upregulated upon infection, and specific only to active infection. While MUC15 did not interact with virus particles or reduce viral replication directly, positive correlations were observed between MUC15 and inflammatory factors in response to viral infection. Given that the upregulation of MUC15 was only triggered late into infection when immune factors (including cytokines, chemokines, EGFR and phosphorylated ERK) started to peak and plateau, MUC15 may potentially serve an immunomodulatory function later during influenza viral infection. CONCLUSIONS: Our study revealed that MUC15 was one of the few cell-surface mucins induced during influenza infection. While MUC15 did not interact directly with influenza virus, we showed that its increase coincides with the peak of immune activation and thus MUC15 may serve an immunomodulatory role during influenza infection.


Assuntos
Vírus da Influenza A Subtipo H3N2/fisiologia , Influenza Humana/patologia , Mucinas/metabolismo , Animais , Células Cultivadas , Quimiocinas/metabolismo , Citocinas/metabolismo , Cães , Células Epiteliais/classificação , Células Epiteliais/metabolismo , Receptores ErbB/metabolismo , Humanos , Influenza Humana/metabolismo , Células Madin Darby de Rim Canino , Mucinas/antagonistas & inibidores , Mucinas/genética , Cavidade Nasal/citologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Regulação para Cima , Replicação Viral/efeitos dos fármacos
5.
J Exp Clin Cancer Res ; 38(1): 283, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262330

RESUMO

BACKGROUND: Mucins are key components of the mucosal barrier in the stomach that protects epithelia from carcinogenic effects of chronic inflammation. Analysis of The Cancer Genome Atlas database indicated that mucin-17 (MUC17) was more highly expressed in gastric cancer (GC) specimens, with favourable prognosis for patients. To explore the underlying mechanisms, we investigated the potential role of MUC17 in controlling chronic gastric inflammation. METHODS: We initially quantified the expression of MUC17 and inflammatory factor, as well as the association of MUC17 with survive in GC using immunohistochemistry. To establish how the inflammatory factors affect MUC17 expression, we explored luciferase reporter, chromatin immunoprecipitation (ChIP), and electrophoretic mobility shift (EMSA) assays. The role and mechanism that MUC17 plays in inflammation-induced cell proliferation was examined in AGS cells with reduced MUC17 expression and MKN45 cells overexpressing a truncated MUC17. RESULTS: We found MUC17 was induced by inflammatory cytokines in GC cells via CDX1upregulation. MUC17 thus inactivated NFκB to inhibit GC cell proliferation in response to pro-inflammatory cytokines. We also revealed that the function of MUC17 was dependent on its conserved epidermal growth factor domain and on downstream sequences to enable its interaction with myosin-9, resulting in a sustained regulatory feedback loop between myosin-9, p53, and RhoA, and then activation of p38 to negatively regulate the NFκB pathway in GC cells. This mechanism was also confirmed in vivo. CONCLUSIONS: Our study demonstrates MUC17 as a GC suppressor protein which has the therapeutic potential for human GC.


Assuntos
Proteínas Motores Moleculares/metabolismo , Mucinas/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Neoplasias Gástricas/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Ciclo Celular/genética , Linhagem Celular Tumoral , Progressão da Doença , Retroalimentação Fisiológica , Mucosa Gástrica/imunologia , Mucosa Gástrica/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Inflamação/metabolismo , Interleucina-8/metabolismo , Camundongos , Mucinas/genética , NF-kappa B/metabolismo , Transdução de Sinais , Neoplasias Gástricas/genética , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/mortalidade , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
6.
Int J Mol Sci ; 20(11)2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31174254

RESUMO

Mycotoxins, which are widely found in feed ingredients and human food, can exert harmful effects on animals and pose a serious threat to human health. As the first barrier against external pollutants, the intestinal mucosa is protected by a mechanical barrier, chemical barrier, immune barrier, and biological barrier. Firstly, mycotoxins can disrupt the mechanical barrier function of the intestinal mucosa, by destroying the morphology and tissue integrity of the intestinal epithelium. Secondly, mycotoxins can cause changes in the composition of mucin monosaccharides and the expression of intestinal mucin, which in turn affects mucin function. Thirdly, mycotoxins can cause damage to the intestinal mucosal immune barrier function. Finally, the microbiotas of animals closely interact with ingested mycotoxins. Based on existing research, this article reviews the effects of mycotoxins on the intestinal mucosal barrier and its mechanisms.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Micotoxinas/toxicidade , Animais , Humanos , Imunidade Inata/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucinas/genética , Mucinas/metabolismo , Micotoxinas/farmacologia
7.
PLoS One ; 14(5): e0216666, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31091244

RESUMO

Mucins and their glycosylation have been suggested to play an important role in colorectal carcinogenesis. We examined potentially functional genetic variants in the mucin genes or genes involved in their glycosylation with respect to colorectal cancer (CRC) risk and clinical outcome. We genotyped 23 single nucleotide polymorphisms (SNPs) covering 123 SNPs through pairwise linkage disequilibrium (r2>0.80) in the MUC1, MUC2, MUC4, MUC5AC, MUC6, and B3GNT6 genes in a hospital-based case-control study of 1532 CRC cases and 1108 healthy controls from the Czech Republic. We also analyzed these SNPs in relation to overall survival and event-free survival in a subgroup of 672 patients. Among patients without distant metastasis at the time of diagnosis, two MUC4 SNPs, rs3107764 and rs842225, showed association with overall survival (HR 1.40, 95%CI 1.08-1.82, additive model, log-rank p = 0.004 and HR 0.64, 95%CI 0.42-0.99, recessive model, log-rank p = 0.01, respectively) and event-free survival (HR 1.31, 95%CI 1.03-1.68, log-rank p = 0.004 and HR 0.64, 95%CI 0.42-0.96, log-rank p = 0.006, respectively) after adjustment for age, sex and TNM stage. Our data suggest that genetic variation especially in the transmembrane mucin gene MUC4 may play a role in the survival of CRC and further studies are warranted.


Assuntos
Neoplasias Colorretais/genética , Mucina-4/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Neoplasias do Colo/genética , Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , República Tcheca , Intervalo Livre de Doença , Feminino , Genótipo , Glicosilação , Humanos , Estimativa de Kaplan-Meier , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Mucina-4/metabolismo , Mucinas/genética , Mucinas/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Intervalo Livre de Progressão , Fatores de Risco
8.
PLoS Negl Trop Dis ; 13(5): e0007418, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31107901

RESUMO

BACKGROUND: Trypanosoma cruzi, the agent of Chagas disease, is a protozoan parasite transmitted to humans by blood-sucking triatomine vectors. However, and despite its utmost biological and epidemiological relevance, T. cruzi development inside the digestive tract of the insect remains a poorly understood process. METHODS/PRINCIPLE FINDINGS: Here we showed that Gp35/50 kDa mucins, the major surface glycoproteins from T. cruzi insect-dwelling forms, are involved in parasite attachment to the internal cuticle of the triatomine rectal ampoule, a critical step leading to its differentiation into mammal-infective forms. Experimental evidence supporting this conclusion could be summarized as follows: i) native and recombinant Gp35/50 kDa mucins directly interacted with hindgut tissues from Triatoma infestans, as assessed by indirect immunofluorescence assays; ii) transgenic epimastigotes over-expressing Gp35/50 kDa mucins on their surface coat exhibited improved attachment rates (~2-3 fold) to such tissues as compared to appropriate transgenic controls and/or wild-type counterparts; and iii) certain chemically synthesized compounds derived from Gp35/50 kDa mucins were able to specifically interfere with epimastigote attachment to the inner lining of T. infestans rectal ampoules in ex vivo binding assays, most likely by competing with or directly blocking insect receptor(s). A solvent-exposed peptide (smugS peptide) from the Gp35/50 kDa mucins protein scaffolds and a branched, Galf-containing trisaccharide (Galfß1-4[Galpß1-6]GlcNAcα) from their O-linked glycans were identified as main adhesion determinants for these molecules. Interestingly, exogenous addition of a synthetic Galfß1-4[Galpß1-6]GlcNAcα derivative or of oligosaccharides containing this structure impaired the attachment of Dm28c but not of CL Brener epimastigotes to triatomine hindgut tissues; which correlates with the presence of Galf residues on the Gp35/50 kDa mucins' O-glycans on the former but not the latter parasite clone. CONCLUSION/SIGNIFICANCE: These results provide novel insights into the mechanisms underlying T. cruzi-triatomine interplay, and indicate that inter-strain variations in the O-glycosylation of Gp35/50 kDa mucins may lead to differences in parasite differentiation and hence, in parasite transmissibility to the mammalian host. Most importantly, our findings point to Gp35/50 kDa mucins and/or the Galf biosynthetic pathway, which is absent in mammals and insects, as appealing targets for the development of T. cruzi transmission-blocking strategies.


Assuntos
Mucinas/metabolismo , Proteínas de Protozoários/metabolismo , Triatoma/parasitologia , Trypanosoma cruzi/metabolismo , Animais , Doença de Chagas/parasitologia , Doença de Chagas/transmissão , Humanos , Mucinas/genética , Proteínas de Protozoários/genética , Reto/parasitologia , Trypanosoma cruzi/genética
9.
PLoS One ; 14(4): e0215237, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30973916

RESUMO

We investigated the significance of MUC21 in EGFR-mutated lung adenocarcinoma (LADC). Two-hundred forty-one surgically resected LADCs (116 EGFR-mutated and 125 wild-type tumors) were examined for immunohistochemical expression of MUC21 protein. A polyclonal antibody and two monoclonal antibodies (heM21C and heM21D) that bind differentially glycosylated MUC21 epitopes were used, and MUC21 proteins detected by these antibodies were named MUC21P, MUC21C, and MUC21D, respectively. MUC21 mRNA levels were semi-quantified and classified into "high" and "low". Among the immunohistochemical expression detected by three different antibodies, high expressors tended to be related to EGFR mutations. The three varieties of the immunohistochemical expressions were related to different histological elements in the EGFR-mutated LADCs. Either MUC21P or MUC21C high expressors had a higher proportion of lepidic elements with low papillary structure and micropapillary elements. MUC21D high expressors had a significantly higher proportion of micropapillary elements (Mann-Whitney test P ≤0.0001). Furthermore, MUC21D high expressors showed high incidence of lymphatic canal invasion and lymph node metastasis (Pearson x2 test, P = 0.0021, P = 0.0125), and a significantly higher recurrence rate (5-year recurrence-free survival 50.7% vs. 73.8%, log-rank test P = 0.0495). MUC21 proteins with a specific glycosylation status may be involved in the progression of EGFR-mutated LADCs, particularly at the stage where tumors are transforming from pure lepidic to micropapillary through low papillary lepidic lesions.


Assuntos
Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Glicoproteínas de Membrana/metabolismo , Mucinas/metabolismo , Adenocarcinoma de Pulmão/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Progressão da Doença , Receptores ErbB/genética , Feminino , Glicosilação , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/patologia , Masculino , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Mucinas/química , Mucinas/genética , Mutação , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
10.
Int J Clin Oncol ; 24(7): 771-778, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30980196

RESUMO

Gastric cancer (GC), one of the most common human cancers, is a heterogeneous disease with different phenotypes, prognoses, and responses to treatment. Understanding the pathogenesis of GC at the molecular level is important for prognosis prediction and determining treatments. Microsatellite instability (MSI), silencing of MLH1, MGMT, and CDKN2A genes by DNA hypermethylation, KRAS mutation, APC mutation, and ERBB2 amplification are frequently found in intestinal type GC. Inactivation of CDH1 and RARB by DNA hypermethylation, and amplification of FGFR and MET, are frequently detected in diffuse type GC. In addition, BST2 and PCDHB9 genes are overexpressed in intestinal type GC. Both genes are associated with GC progression. GC can be divided into gastric/intestinal mucin phenotypes according to mucin expression. MSI, alterations of TP73, CDH1 mutation, and DNA methylation of MLH are detected frequently in the gastric mucin phenotype. TP53 mutation, deletion of APC, and DNA methylation of MGMT are detected frequently in the intestinal mucin phenotype. FKTN is overexpressed in the intestinal mucin phenotype, and IQGAP3 is overexpressed in the gastric mucin phenotype. These genes are involved in GC progression. To characterize cancer stem cells, a useful method is spheroid colony formation. KIFC1 and KIF11 genes show more than twofold higher expression in spheroid-forming cells than that in parental cells. Both KIF genes are overexpressed in GC, and knockdown of these genes inhibits spheroid formation. Alterations of these molecules may be useful to understand gastric carcinogenesis. Specific inhibitors of these molecules may also be promising anticancer drugs.


Assuntos
Biomarcadores Tumorais/genética , Mucinas/genética , Células-Tronco Neoplásicas/patologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Fenótipo , Prognóstico , Neoplasias Gástricas/classificação
11.
Oral Dis ; 25(5): 1325-1334, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30920100

RESUMO

OBJECTIVES: To determine expression and localization of membrane-associated mucins within human keratinized and non-keratinized oral epithelia, and to explore transcriptional changes associated with primary Sjögren's syndrome. SUBJECTS AND METHODS: Mucin transcripts and glycoproteins were determined by RT-PCR and immunohistochemistry, respectively, in oral keratinized (hard palate) and non-keratinized (buccal) epithelia obtained from three cadavers. Mucin transcripts assessed by quantitative PCR were compared between cells harvested by brushing buccal and palatal epithelia of 25 female primary Sjögren's syndrome patients vs 25 healthy age-matched female control subjects. RESULTS: In hard palate, MUC4 is absent and MUC1 localized to deeper cell layers. Both mucins are within the apical layers of buccal epithelium. MUC15 is localized throughout all palatal cell layers and in all but the basal layer of buccal epithelia. MUC16, MUC20, and MUC21 glycoproteins are localized within all but the basal cell layer of both tissue types. In buccal cells of primary Sjögren's patients, MUC21 transcripts are down-regulated 3.4-fold and MUC20 2.6-fold. Dysregulation of select epithelial mucins may therefore contribute to xerostomia. CONCLUSIONS: Differential expression of multiple mucins and down-regulation in Sjögren's syndrome support further study of oral epithelial mucin physiology and pathophysiology, including their functions in hydration and lubrication of the oral mucosal pellicle.


Assuntos
Mucosa Bucal/metabolismo , Mucosa Bucal/patologia , Mucinas/metabolismo , Síndrome de Sjogren/metabolismo , Síndrome de Sjogren/patologia , Adulto , Idoso , Estudos de Casos e Controles , Película Dentária , Epitélio , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Mucinas/genética , Síndrome de Sjogren/genética
13.
Toxicol Lett ; 309: 1-9, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30904571

RESUMO

Aflatoxin M1 (AFM1), ochratoxin A (OTA), and zearalenone (ZEA) are mycotoxins commonly found in milk. Mycotoxin contamination has caused food safety concerns worldwide since most of the toxic effects in humans are serious. The combined toxic effects of these mycotoxins on intestinal epithelial cells have not been reported. Herein, we investigated the combined effects of AFM1, OTA, and ZEA on intestinal integrity and define the underlying mechanisms(s) of their effects in Caco-2/HT29-MTX co-cultures. Our results showed that the mixtures of AFM1 + OTA, AFM1 + ZEA, and AFM1 + ZEA + OTA significantly increased epithelial permeability. Immunofluorescence analysis and transmission electron microscopy revealed that mycotoxins altered TJ proteins morphology and disrupted their structures. Also, the present study showed that mixtures of mycotoxins significantly modulated MUC5AC and MUC5B mRNA levels and protein secretion. This study demonstrated that the effects of mixtures of mycotoxins on intestinal barrier function were more significant than AFM1 alone. More importantly, the damage of intestinal integrity caused by mycotoxins was correlated to the change of the TJ proteins location and the decrease of mucin secretion. Mixtures of AFM1, OTA, and ZEA in food might pose a health risk to consumers, particularly in children, and toxin risks should be considered.


Assuntos
Aflatoxina M1/toxicidade , Mucosa Intestinal/efeitos dos fármacos , Mucinas/metabolismo , Ocratoxinas/toxicidade , Zearalenona/toxicidade , Células CACO-2 , Técnicas de Cocultura , Contaminação de Alimentos , Células HT29 , Humanos , Mucosa Intestinal/metabolismo , Mucina-5AC/análise , Mucina-5AC/genética , Mucina-2/análise , Mucina-2/genética , Mucina-5B/análise , Mucina-5B/genética , Mucinas/genética , Permeabilidade , RNA Mensageiro/análise , Proteínas de Junções Íntimas/análise
14.
PLoS One ; 14(3): e0213527, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30861027

RESUMO

Mitochondrial function has been implicated and studied in numerous complex age-related diseases. Understanding the potential role of mitochondria in disease pathophysiology is of importance due to the rise in prevalence of complex age-related diseases, such as type 2 diabetes (T2D) and Alzheimer's disease (AD). These two diseases specifically share common pathophysiological characteristics which potentially point to a common root cause or factors for disease exacerbation. Studying the shared phenomena in Mexican Americans is of particular importance due to the disproportionate prevalence of both T2D and AD in this population. Here, we assessed the potential role of mitochondria in T2D and cognitive impairment (CI) in a Mexican American cohort by analyzing blood-based indices of mitochondrial DNA copy number (mtDNACN) and cell-free mitochondrial DNA (CFmtDNA). These mitochondrial metrics were also analyzed for correlation with relevant neuropsychological variables and physiological data collected as indicators of disease and/or disease progression. We found mtDNACN to be significantly decreased in individuals with CI, while CFmtDNA was significantly elevated in T2D; further, CFmtDNA elevation was significantly exacerbated in individuals with both diseases. MtDNACN was found to negatively correlate with age and fatty acid binding protein concentration, while positively correlating with CFmtDNA as well as CERAD total recall score. Candidate gene SNP-set analysis was performed on genes previously implicated in maintenance and control of mitochondrial dynamics to determine if nuclear variants may account for variability in mtDNACN. The results point to a single significant locus, in the LRRK2/MUC19 region, encoding leucine rich repeat kinase 2 and mucin 19. This locus has been previously implicated in Parkinson's disease, among others; rs7302859 was the driver SNP. These combined findings further indicate that mitochondrial dysfunction (as assessed by proxy via mtDNACN) is intimately linked to both T2D and CI phenotypes as well as aging.


Assuntos
Ácidos Nucleicos Livres , Disfunção Cognitiva , DNA Mitocondrial , Diabetes Mellitus Tipo 2 , Americanos Mexicanos , Idoso , Doença de Alzheimer/sangue , Doença de Alzheimer/etnologia , Doença de Alzheimer/genética , Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/genética , Disfunção Cognitiva/sangue , Disfunção Cognitiva/etnologia , Disfunção Cognitiva/genética , DNA Mitocondrial/sangue , DNA Mitocondrial/genética , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/genética , Feminino , Loci Gênicos , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Masculino , Pessoa de Meia-Idade , Mucinas/genética , Polimorfismo de Nucleotídeo Único
15.
PLoS One ; 14(2): e0211861, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30742646

RESUMO

To use human limbal explants as an alternative source for generating conjunctival epithelium and to determine the effect of interleukin-13 (IL-13) on goblet cell number, mucin expression, and stemness. Human limbal explants prepared from 17 corneoscleral rims were cultured with or without IL-13 (IL-13+ and IL-13-, respectively) and followed up to passage 2 (primary culture [P0]-P2). Cells were characterized by alcian blue/periodic acid-Schiff (AB/PAS) staining (goblet cells); immunofluorescent staining for p63α (progenitor cells), Ki-67 (proliferation), MUC5AC (mucin, goblet cells), and keratin 7 (K7, conjunctival epithelial and goblet cells); and by quantitative real-time polymerase chain reaction for expression of the p63α (TP63), MUC5AC, MUC4 (conjunctival mucins), K3, K12 (corneal epithelial cells), and K7 genes. Clonogenic ability was determined by colony-forming efficiency (CFE) assay. Using limbal explants, we generated epithelium with conjunctival phenotype and high viability in P0, P1, and P2 cultures under IL-13+ and IL-13- conditions, i.e., epithelium with strong K7 positivity, high K7 and MUC4 expression and the presence of goblet cells (AB/PAS and MUC5AC positivity; MUC5AC expression). p63α positivity was similar in IL-13+ and IL-13- cultures and was decreased in P2 cultures; however, there was increased TP63 expression in the presence of IL-13 (especially in the P1 cultures). Similarly, IL-13 increased proliferative activity in P1 cultures and significantly promoted P0 and P1 culture CFE. IL-13 did not increase goblet cell number in the P0-P2 cultures, nor did it influence MUC5AC and MUC4 expression. By harvesting unattached cells on day 1 of P1 we obtained goblet cell rich subpopulation showing AB/PAS, MUC5AC, and K7 positivity, but with no growth potential. In conclusion, limbal explants were successfully used to develop conjunctival epithelium with the presence of putative stem and goblet cells and with the ability to preserve the stemness of P0 and P1 cultures under IL-13 influence.


Assuntos
Células Epiteliais/metabolismo , Interleucina-13/farmacologia , Mucinas/genética , Células-Tronco/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Túnica Conjuntiva/citologia , Túnica Conjuntiva/metabolismo , Células Epiteliais/citologia , Extremidades/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Células Caliciformes/efeitos dos fármacos , Células Caliciformes/metabolismo , Humanos , Interleucina-13/metabolismo , Limbo da Córnea/crescimento & desenvolvimento , Limbo da Córnea/metabolismo
16.
Cancer Genet ; 231-232: 67-79, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30803560

RESUMO

BACKGROUND: Usually, genes with a higher-than-expected number of somatic mutations in tumor samples are assumed to be cancer related. We identified genes with a fewer-than-expected number of somatic mutations - "untouchable genes". METHODS: To predict the expected number of somatic mutations, we used a linear regression model with the number of mutations in the gene as an outcome, and gene characteristics, including gene size, nucleotide composition, level of evolutionary conservation, expression level and others, as predictors. Analysis of residuals from the regression model was used to compare the observed and predicted number of mutations. RESULTS: We have identified 19 genes with a less-than-expected number of loss-off-function (nonsense, frameshift or pathogenic missense) mutations - i.e., untouchable genes. The number of silent or neutral missense mutations in untouchable genes was equal or higher than the expected number. Many mucins, including MUC16, MUC17, MUC6, MUC5AC, MUC5B, and MUC12, are untouchable. We hypothesized that untouchable mucins help tumor cells to avoid immune response by providing a protective coat that prevents direct contact between effector immune cells, e.g., cytotoxic T-cells, and tumor cells. Survival analysis of available TCGA data demonstrated that overall survival of patients with low (below the median) expression of untouchable mucins was better compared to patients with high expression of untouchable mucins. Aside from mucins, we have identified a number of other untouchable genes. CONCLUSIONS: Untouchable genes may be ideal targets for cancer treatment since suppression of untouchable genes is expected to inhibit survival of tumor cells.


Assuntos
Genes Neoplásicos , Genoma Humano , Neoplasias/genética , Neoplasias/terapia , Códon sem Sentido/genética , Mutação da Fase de Leitura/genética , Humanos , Modelos Lineares , Mutação com Perda de Função/genética , Mucinas/genética , Mutação de Sentido Incorreto/genética , Análise de Sobrevida
17.
Adv Clin Exp Med ; 28(2): 165-169, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30640414

RESUMO

BACKGROUND: Dry eye syndrome (DES) is a common symptom of tear film instability and ocular surface damage due to an abnormal quality and quantity of tears, including the sensation of foreign objects and blurred vision. Among all factors for tear film stability, MUC5AC and MUC19 are very important; the levels of both mucins are associated with the pathogenesis of DES. OBJECTIVES: The aim of this study was to explore the expression of MUC5AC and MUC19 on the ocular surface in a DES model of ovariectomized female rabbits. MATERIAL AND METHODS: Healthy female New Zealand white rabbits (n = 18; age: 1 year, weight: 2.5 ±0.6 kg) were randomly assigned to a test group and a control group. The DES model was constructed in ovariectomized female rabbits. Indicators of ocular surface injury, such as Schirmer's test, corneal fluorescence staining, a conjunctival imprinting cytology test, and the expression of MUC5AC and MUC19 in conjunctival tissues were evaluated by immunohistochemistry in week 1, week 2 and week 4. RESULTS: Both the length of soaked test paper and the total scores of corneal fluorescence staining at all time-points were significantly lower in the test group than in the control group, and they decreased over time (p < 0.05). The grades of imprinted cells at all time-points were significantly higher in the test group than in the control group, and they increased over time (p < 0.05). The percentage of goblet cells was significantly lower in the test group than in the control group, and it decreased over time (p < 0.05). The percentages of cells with a positive expression of MUC5AC and MUC19 at all time-points were significantly lower in the test group than in the control group, and they decreased over time (p < 0.05). CONCLUSIONS: The pathogenesis of DES is associated with an increased grade of imprinted cells, decreased goblet cells, and a decreased expression of MUC5AC and MUC19.


Assuntos
Túnica Conjuntiva/metabolismo , Síndromes do Olho Seco/metabolismo , Células Caliciformes , Aparelho Lacrimal/metabolismo , Mucinas/metabolismo , Animais , Feminino , Mucina-5AC , Mucinas/genética , RNA Mensageiro/genética , Coelhos , Distribuição Aleatória , Lágrimas/metabolismo
18.
J Nutr ; 149(2): 249-257, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30649390

RESUMO

BACKGROUND: Vegetable consumption reduces colon cancer risk when fed in the initiation stage of carcinogenesis; however, the effect of vegetable consumption during the post-initiation stage has rarely been examined. OBJECTIVE: We investigated the chemopreventive effects of feeding apiaceous and cruciferous vegetables on colon cancer risk in the post-initiation stage. METHODS: Thirty male Wistar rats (∼5 wk, 92 g) were subcutaneously injected with 1,2-dimethylhydrazine 1 time/wk for 2 wk. One week after the last dose, rats were randomly assigned to 3 groups: the basal diet, an apiaceous vegetable-containing diet (API; 21% fresh wt/wt), or a cruciferous vegetable-containing diet (CRU; 21% fresh wt/wt). All diets contained ∼20% protein, 7% fat, and 63% digestible carbohydrate. Experimental diets were fed for 10 wk, after which colons were harvested. RESULTS: CRU reduced aberrant crypt foci (ACF) number compared to the basal group (P = 0.014) and API (P = 0.013), whereas API decreased the proportion of dysplastic ACF relative to the basal group (P < 0.05). Both CRU and API reduced doublecortin-like kinase 1-positive marker expression relative to basal by 57.9% (P = 0.009) and 51.4% (P < 0.02). The numbers of CD44-positive ACF did not differ between the groups. We identified 14 differentially expressed microRNAs (miRNAs). Of these, expression of 6 miRNAs were greater or tended to be greater (P ≤ 0.10) in one or both vegetable-containing groups compared to the basal group. Bioinformatic analysis of these expression changes in miRNA predicted a change in WNT/ß-catenin signaling, indicating downregulation of ß-catenin in the vegetable-fed groups. Consistent with this bioinformatics analysis, ß-catenin-accumulated ACF were decreased in CRU (93.1%, P = 0.012), but not in API (54.4%, P = 0.125), compared to the basal group. CONCLUSION: Both apiaceous and cruciferous vegetables, fed post-initiation, reduce colonic preneoplastic lesions as well as cancer stem cell marker expression in rats, possibly by suppressing oncogenic signaling through changes in miRNA expression.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias do Colo/dietoterapia , Dieta , Verduras/classificação , 1,2-Dimetilidrazina/toxicidade , Animais , Biomarcadores Tumorais/sangue , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Mucinas/genética , Mucinas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , beta Catenina/genética , beta Catenina/metabolismo
19.
Mol Biochem Parasitol ; 227: 19-24, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30481538

RESUMO

This study focuses on the host-parasite relationship of human Ascaris lumbricoides, which is a parasite of the small intestine and is also one of the commonest parasites worldwide. As part of this investigation, we examined the host-parasite relationship assuming that there is a common antigenicity, shared protein between A. lumbricoides and human small intestinal mucosa, using molecular techniques. We obtained three DNA clones from human colon cDNA library by screening for anti-A. lumbricoides polyclonal antibodies. The transmembrane mucin12 gene was identified after sequencing analysis of these clones. Specific signals of immunostaining with polyclonal anti-mucin12 antibodies were observed in the mucous secretory organs, epidermis, and intestinal canal of A. lumbricoides. These signals disappeared when immunohistochemistry was performed using pre-absorbed polyclonal antibodies with a specific peptide. These results suggest that mucin12 is localized in the mucous secretory organs in the epidermis of A. lumbricoides. Furthermore, we examined the site of mucin12 localization in the host; specific mucin12 signals were observed on the mucosal epithelia present around intestinal crypts and villi of the small intestine. Therefore, we suggest that mucin12 is a protein that shows common antigenicity in both A. lumbricoides and its host. It is presumed that adult A. lumbricoides live in their preferred environment, which is the small intestine, by secreting mucin12 to avoid being attacked by the host immune system.


Assuntos
Ascaríase/genética , Ascaris lumbricoides/genética , Proteínas de Helminto/genética , Intestino Delgado/metabolismo , Mucinas/genética , Animais , Ascaríase/metabolismo , Ascaríase/parasitologia , Ascaris lumbricoides/metabolismo , Proteínas de Helminto/metabolismo , Humanos , Intestino Delgado/parasitologia , Mucinas/metabolismo , Transporte Proteico
20.
Arch Oral Biol ; 97: 52-58, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30343214

RESUMO

OBJECTIVES: Mucins are heavily glycosylated large glycoproteins produced in the salivary glands that contribute to salivary viscosity. This study aimed to characterize age-related changes in mucin production in mouse submandibular salivary gland (SMG). METHODS: The paraffin sections of the SMGs of the young and aged mice were stained with HE or Alcian blue (AB). SMGs mucins derived from the young and aged mice were separated using supported molecular matrix electrophoresis (SMME). After SMME, the membranes were stained with AB and subsequent glycan analysis or subjected to immunoblotting. The expression of 18 mucin genes and 4 sialyltransferase genes in the young and aged SMGs were determined by qPCR. The neuraminidase activity in the SMG homogenates was determined using Neuraminidase Assay Kit. RESULTS: The mouse SMG is more strongly stained by AB with increasing age. On SMME, a characteristic band not found in the young SMG is detected in aged SMG. Based on migration position and the MALDI MS, the band that appeared specifically with aging was determined to be acidic mucin. Additionally, most glycans of this acidic mucin were sialo-oligosaccharides. Furthermore, there was an increase in the expression of sialyltransferase genes ST6GalNAc I and ST6GalNAc II, but not a decrease in neuraminidase activity, in the SMG of aged mice. CONCLUSION: A sialomucin or sialylated mucin-like molecule not found in the SMGs of young WT mice is expressed in aged WT mice. The increase in the sialo-oligosaccharide content in this aging-associated molecule may be attributed to the increased expression of the sialyltransferase genes.


Assuntos
Mucinas/metabolismo , Oligossacarídeos/metabolismo , Sialiltransferases/metabolismo , Glândula Submandibular/metabolismo , Fatores Etários , Animais , Expressão Gênica , Immunoblotting , Camundongos , Camundongos Endogâmicos C57BL , Mucinas/genética , Neuraminidase/genética , Neuraminidase/metabolismo , Oligossacarídeos/genética , Reação em Cadeia da Polimerase , Polissacarídeos/genética , Polissacarídeos/metabolismo , Sialiltransferases/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
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