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1.
Toxicol Appl Pharmacol ; 307: 108-114, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27491593

RESUMO

Estrogens and progestins are widely used in combination in human medicine and both are present in aquatic environment. Despite the joint exposure of aquatic wildlife to estrogens and progestins, very little information is available on their combined effects. In the present study we investigated the effect of ethinylestradiol (EE2) and Levonorgestrel (LNG), alone and in mixtures, on the expression of the brain specific ER-regulated cyp19a1b gene. For that purpose, recently established zebrafish-derived tools were used: (i) an in vitro transient reporter gene assay in a human glial cell line (U251-MG) co-transfected with zebrafish estrogen receptors (zfERs) and the luciferase gene under the control of the zebrafish cyp19a1b gene promoter and (ii) an in vivo bioassay using a transgenic zebrafish expressing GFP under the control of the zebrafish cyp19a1b gene promoter (cyp19a1b-GFP). Concentration-response relationships for single chemicals were modeled and used to design the mixture experiments following a ray design. The results from mixture experiments were analyzed to predict joint effects according to concentration addition and statistical approaches were used to characterize the potential interactions between the components of the mixtures (synergism/antagonism). We confirmed that some progestins could elicit estrogenic effects in fish brain. In mixtures, EE2 and LNG exerted additive estrogenic effects both in vitro and in vivo, suggesting that some environmental progestin could exert effects that will add to those of environmental (xeno-)estrogens. Moreover, our zebrafish specific assays are valuable tools that could be used in risk assessment for both single chemicals and their mixtures.


Assuntos
Aromatase/genética , Encéfalo/efeitos dos fármacos , Estrogênios/farmacologia , Etinilestradiol/farmacologia , Levanogestrel/farmacologia , Progestinas/farmacologia , Proteínas de Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Bioensaio , Encéfalo/metabolismo , Linhagem Celular , Interações Medicamentosas , Embrião não Mamífero , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Luciferases/genética , Luciferases/metabolismo , Peixe-Zebra
2.
Pediatr Diabetes ; 17 Suppl 23: 32-37, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-28334496

RESUMO

BACKGROUND: Seasonality at the clinical onset of type 1 diabetes (T1D) has been suggested by different studies, however, the results are conflicting. This study aimed to evaluate the presence of seasonality at clinical onset of T1D based on the SWEET database comprising data from 32 different countries. METHODS: The study cohort included 23 603 patients (52% males) recorded in the international multicenter SWEET database (48 centers), with T1D onset ≤20 years, year of onset between 1980 and 2015, gender, year and month of birth and T1D-diagnosis documented. Data were stratified according to four age groups (<5, 5-<10, 10-<15, 15-20 years) at T1D onset, the latitude of European center (Northern ≥50°N and Southern Europe <50°N) and the year of onset ≤ or >2009. RESULTS: Analysis by month revealed significant seasonality with January being the month with the highest and June with the lowest percentage of incident cases (P < .001). Winter, early spring and late autumn months had higher percentage of incident cases compared with late spring and summer months. Stratification by age showed similar seasonality patterns in all four age groups (P ≤ .003 each), but not in children <24 months of age. There was no gender or latitude effect on seasonality pattern, however, the pattern differed by the year of onset (P < .001). Seasonality of diagnosis conformed to a sinusoidal model for all cases, females and males, age groups, northern and southern European countries. CONCLUSIONS: Seasonality at T1D clinical onset is documented by the large SWEET database with no gender or latitude (Europe only) effect except from the year of manifestation.


Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Estações do Ano , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Europa (Continente)/epidemiologia , Feminino , Humanos , Lactente , Masculino , Adulto Jovem
3.
Environ Sci Pollut Res Int ; 22(21): 16393-404, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25471715

RESUMO

Assessment of exposure and effect of fish to pharmaceuticals that contaminate aquatic environment is a current major issue in ecotoxicology and there is a need to develop specific biological marker to achieve this goal. Benzyloxy-4-trifluoromethylcoumarin-O-debenzyloxylase (BFCOD) enzymatic activity has been commonly used to monitor CYP3A activity in fish. In this study, we assessed the capacity of a panel of toxicologically relevant chemicals to modulate BFCOD activity in fish, by using in vitro and in vivo bioassays based on fish liver cell lines (PLHC-1, ZFL, RTL-W1) and zebrafish embryos, respectively. Basal BFCOD activity was detectable in all biological models and was differently modulated by chemicals. Ligands of human androgens, glucocorticoids, or pregnanes X receptors (i.e., dexamethasone, RU486, rifampicin, SR12813, T0901317, clotrimazole, ketoconazole, testosterone, and dihydrotestosterone) moderately increased or inhibited BFCOD activity, with some variations between the models. No common feature could be drawn by regards to their capacity to bind to these receptors, which contrasts with their known effect on mammalian CYP3A. In contrast, dioxins and polycyclic aromatic hydrocarbons (PAHs) strongly induced BFCOD activity (up to 30-fold) in a time- and concentration-dependent manner, both in vitro in all cell lines and in vivo in zebrafish embryos. These effects were AhR dependent as indicated by suppression of induced BFCOD by the AhR pathway inhibitors 8-methoxypsoralen and α-naphthoflavone. Altogether our result further question the relevance of using liver BFCOD activity as a biomarker of fish exposure to CYP3A-active compounds such as pharmaceuticals.


Assuntos
Citocromo P-450 CYP1A1/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/enzimologia , Poluentes Ambientais/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Peixe-Zebra/embriologia , Animais , Linhagem Celular , Poluentes Ambientais/metabolismo , Feminino , Humanos , Ligantes , Fígado/enzimologia , Masculino
4.
Nutr Diabetes ; 3: e94, 2013 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-24166423

RESUMO

BACKGROUND: Children and adolescents with overt type 1 diabetes (T1D) have been found to show an altered carnitine profile. This pattern has not previously been analyzed in neonates before onset of the disease. MATERIALS AND METHODS: Fifty children who developed T1D during the first 6 years of life, born and living in the Tuscany and Umbria Regions of Italy, were identified and 200 controls were recruited into the study. All newborns were subjected to extended neonatal screening by mass spectrometry at 48-72 h of life. Four controls for each of the 50 index cases were taken randomly and blinded in the same analytical batch. The panel used for neonatal screening consists of 13 amino acids, free carnitine, 33 acyl-carnitines and 21 ratios. All Guthrie cards are analyzed within 2 days of collection. RESULTS: Total and free carnitine were found to be significantly lower in neonates who later developed T1D compared with controls. Moreover, the concentrations of the acyl-carnitines - acetyl-L-carnitine (C2), proprionylcarnitine (C3), 3-hydroxyisovalerylcarnitine (C5OH), miristoylcarnitine (C4), palmitoylcarnitine (C16) and stearoylcarnitine (C18) - were also significantly low in the cases vs controls. Furthermore, total amino-acid concentrations, expressed as the algebraic sum of all amino acids tested, showed a trend toward lower levels in cases vs controls. CONCLUSIONS: We found that carnitine and amino-acid deficit may be evident before the clinical appearance of T1D, possibly from birth. The evaluation of these metabolites in the neonatal period of children human leukocyte antigen genetically at 'risk' to develop T1D, could represent an additional tool for the prediction of T1D and could also offer the possibility to design new strategies for the primary prevention of the disease from birth.

5.
Int J Immunopathol Pharmacol ; 25(2): 547-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22697090

RESUMO

Type 1 diabetes (T1D) is a heterogeneous disorder characterized by destruction of pancreatic beta cells, culminating in loss of insulin secretion. Data from large epidemiologic studies worldwide indicate that during the last decades the incidence of T1D has increased significantly, reaching percentages of 2-5% annually. This increase suggests that there is a significant environmental contribution impacting the development of the disease, since genetic factors alone can hardly explain the rapid increase. Studies regarding T1D epidemiology in diverse populations aim to identify the disease causal factors and new targets for intervention. Viruses are one of the environmental factors implicated in the development of T1D in susceptible individuals. Recent studies suggest an association of T1D with H1N1 influenza. We would like to comment on this association and report our experience. Prospective studies are necessary to assess whether H1N1 infection is involved in T1D pathogenesis and provide directions on how to deal with viral infections in diabetes-susceptible individuals.


Assuntos
Diabetes Mellitus Tipo 1/etiologia , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/complicações , Influenza Humana/diagnóstico , Feminino , Humanos , Masculino
6.
Eur J Med Genet ; 50(1): 21-32, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17088112

RESUMO

We report a patient with a de novo interstitial deletion of the long arm of chromosome 2 involving bands 2q24.3-q31.1. The patient shows postnatal growth retardation, microcephaly, ptosis, down-slanting palpebral fissures, long eyelashes and micrognathia. Halluces are long, broad and medially deviated, while the other toes are laterally deviated and remarkably short with hypoplastic phalanges. She also showed developmental delay, seizures, lack of eye contact, stereotypic and repetitive hand movements and sleep disturbances with breath holding. Prenatal and three independent postnatal karyotypes were normal. Array-CGH analysis allowed us to identify and characterize a "de novo" 2q interstitial deletion of about 10.4Mb, involving segment between cytogenetic bands 2q24.3 and 2q31.1. The deletion was confirmed by quantitative PCR. About 30 children with 2q interstitial deletion have been reported. The deletion described here is overlapping with 15 of these cases. We have attempted to compare the clinical features of our patient with 15 overlapping cases. The emerging phenotypes include low birth weight, postnatal growth retardation, mental retardation and developmental delay, microcephaly, and peculiar facial dysmorphisms. Peculiar long and broad halluces with an increased distance between the first and the second toe are ("sandal gap" sign) present in most of the described patients. The gene content analysis of the deleted region revealed the presence of some genes that may be indicated as good candidates in generating both neurological and dysmorphic phenotype in the patient. In particular, a cluster of SCNA genes is located within the deleted region and it is known that loss of function mutations in SCNA1 gene cause a severe form of epilepsy.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 2/genética , Anormalidades Múltiplas/genética , Blefaroptose/genética , Pré-Escolar , Feminino , Transtornos do Crescimento/genética , Humanos , Microcefalia/genética
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