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ABSTRACT: Docosahexaeonic acid (DHA) is the final compound in the omega-3 polyunsaturated fatty acids (PUFA) synthetic pathway and the most abundant PUFA found in the brain. DHA plays an essential role in the development of the brain, and the intakes in pregnancy and early life affect growth and cognitive performance later in childhood. Recently, it has been proposed that dietary intake of DHA could be a non-pharmacological interventional strategy for the treatment of seizures in humans. However, to date, the experimental approaches to study the antiepileptic effect of DHA have been exclusively restricted to rodent models during short-to-medium periods of treatment. The purpose of the present study was to test the chronic anticonvulsivant effects of DHA supplementation in zebrafish from the pre-spawning stage to aging, taking advantage of our recently described kainate-induced seizure model using this animal. To that end, two groups of adult female zebrafish were fed with standard or 200mg/kg DHA-enriched diets during 1 month previous to the spawning, and offspring subdivided in two categories, and subsequently fed with standard or DHA diets, generating 4 groups of animals that were aged until 20 months. Afterward, KA was intraperitoneally administered and epileptic score determined. All the DHA-enriched groups presented antiepileptic effects compared to the control group, showing that DHA presents an anticonvulsant potential. Among the studied groups, zebrafish fed with DHA from the pre-spawning stage to aging presented the best antiepileptic profile. These results show a neuroprotective benefit in zebrafish fed with DHA-enriched diet before birth and during the whole life.
Brain research bulletin 04/2012; 88(5):467-70. · 2.18 Impact Factor
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ABSTRACT: Glutamate is the major excitatory neurotransmitter of the central nervous system in vertebrates. Excitotoxicity, caused by over-stimulation of the glutamate receptors, is a major cause of neuron death in several brain diseases, including epilepsy. We describe here how behavioural seizures can be triggered in adult zebrafish by the administration of kainate and are very similar to those observed in rodent models. Kainate induced a dose-dependent sequence of behavioural changes culminating in clonus-like convulsions. Behavioural seizures were suppressed by DNQX (6,7-dinitroquinoxaline-2,3-dione) dose-dependently, whilst MK-801 (a non-competitive NMDA receptor antagonist) had a lesser effect. Kainate triggers seizures in adult zebrafish, and thus this species can be considered as a new model for studying seizures and subsequent excitotoxic brain injury.
European Journal of Neuroscience 03/2011; 33(7):1252-5. · 3.63 Impact Factor
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ABSTRACT: N-Heterocyclic carbene (NHC) ligands have attracted great interest over the last decade for their use in the design of homogenous catalysts. NHC-based metal complexes have interesting potential biomedical applications, such as in antimicrobial and cancer therapy, which are beginning to be explored more fully. We have studied here the oxidant activities of a series of Ru(II) complexes in vitro and zebrafish (Danio rerio) have been used as a model in vivo to investigate and characterize the toxicity of some of these compounds. Dual behavior was observed for the NHC-based complexes as they behaved as antioxidants at low concentrations but showed pro-oxidant capacity at higher concentrations. Zebrafish embryos were exposed to Ru(II) complexes under several different conditions (0 or 24 h postfertilization, with or without the chorion) and various parameters, such as viability, edema, heart rate, blood coagulation, pigmentation, scoliosis, malformation, and hatching, were tested. In general, zebrafish embryos were not harmed by exposure to Ru(II) complexes whatever the experimental conditions. Several toxicity profiles were observed depending upon the chemical structure of the compound in question. Their characteristics as pro-oxidant and/or antioxidant agents together with their biosafety may point to their having biomedical applications as antitumoral or neuroprotective drugs.
Zebrafish 03/2010; 7(1):13-21. · 3.08 Impact Factor
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ABSTRACT: The zebrafish (Danio rerio) is rapidly gaining ground as a disease model. However, until now, the use of this species with human pathogens has been restricted to just three bacteria; no studies involving viruses that infect humans are recorded. In this study, the zebrafish was used as a model of herpes simplex virus type 1 (HSV-1) infection of the nervous system. Fish infected using viral culture supernatants showed detectable HSV-1 DNA concentrations 1-4 days after inoculation, indicating that this virus can experimentally infect and persist in this host. The kinetics of infection was dose dependent, especially in the head. Histological immunodetection of HSV-1 glycoproteins confirmed the presence of HSV-1 in the organs studied; infection led to histopathological changes. Moreover, the suppression of the immune system by cyclophosphamide and the antiviral effect of acyclovir were demonstrated. The infection of the encephalon was studied in detail, and the time course of viral colonization recorded. Immunofluorescence studies provided immunoreactive evidence of viral antigens in the encephalon and spinal cord. Viruses cleared from infected brains showed the ability to infect human neuroblastoma cells. This study is the first to demonstrate HSV-1 infection in the zebrafish and manifests the potential use of this species in herpesvirus studies.
Zebrafish 01/2009; 5(4):323-33. · 3.08 Impact Factor
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ABSTRACT: Disseminated herpes simplex virus type 1 (HSV-1) infection during pregnancy is poorly described even though it is associated with high maternal and fetal morbidity and neonatal mortality in humans. In a previous paper using mice as a model, the authors demonstrated that HSV-1 is transmitted hematogenously from mother to offspring, the virus colonizing the central nervous system and provoking high mortality. In the present study, viral DNA levels in latently infected mothers were investigated during pregnancy and after delivery in mice. Samples from different organs were obtained before gestation (latency), three times during pregnancy (17, 4.5, and 1 day before delivery), and four times after delivery (1 day, 1 week, 1 and 2 months). A dramatic decrease in viral DNA concentration was observed during pregnancy, especially in the nervous system, with postnatal recovery to latent levels. All the brain regions studied showed similar trends. The viral copy numbers detected in mothers at delivery +1 day were independent of viral inoculum size. The spread of the virus to the above organs was examined immunohistochemically and, in general, more intense viral staining was observed after delivery in each. Because immunoglobulin levels can be modified by infections during pregnancy, the authors examined the levels of specific HSV-1 antibodies. Variation in HSV-1 DNA concentration was found to be associated with changes in the full spectrum of immunoglobulins (but especially immunoglobulin M [IgM]) over pregnancy, whereas at delivery -1 day a significant inverse relationship between immunoglobulins and HSV-1 DNA was observed. IgGs provided protection during the postnatal phase.
Journal of NeuroVirology 07/2007; 13(3):233-41. · 2.31 Impact Factor
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ABSTRACT: Herpes simplex virus type 1 (HSV-1) is a neurotropic virus that causes severe disease and death in newborn humans but, to date, it remains unclear how neonatal infection occurs. We show here that the vertical transmission of HSV-1 in mice is mainly hematogenous and involves the colonization of the neonate central nervous system (CNS). HSV-1 DNA was mainly detected in the blood and CNS of the offspring born to latently infected mothers; no significant differences were seen between the viral DNA concentrations in the blood of these mothers and their female progeny (either neonate or adult). The administration of acyclovir during gestation reduced or eliminated both the maternal and the neonatal viral DNA in the blood. Embryo transfer was performed to ensure (as far as possible) that only vertical hematogenous infection took place. Immunohistochemical analysis detected viral proteins in the encephalon of the offspring. Immunofluorescence studies provided immunoreactive evidence of HSV-1 proteins in the neurons of the hippocampus and showed that these viruses can molecularly reactivate after hyperthermia. Neonatal HSV-1 infection therefore appears to be mainly caused by hematogenous vertical transmission, and the viruses that colonize the offspring CNS are capable of molecular reactivation after a period of latency.
Journal of Virology 04/2006; 80(6):2823-31. · 5.40 Impact Factor
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ABSTRACT: Herpes simplex virus type 1 (HSV-1) causes disease in humans and animals. Infection usually occurs via the neural route and possibly occurs via the hematogenous route. The latter, however, is the main route by which immunosuppressed individuals and neonates are infected. Gender-dependent differences in the incidence and severity of some viral infections have been reported. To detect differences between the sexes with respect to HSV-1 colonization and disease, the characteristics of both acute and latent infections in hematogenously infected male and female mice were compared. In acute infection, the female mice had a poorer outcome: HSV-1 colonization was more effective, especially in the gonads and brain. In the encephalon, the midbrain had the highest viral load. In latent infection, brain viral loads were not significantly different with respect to sex. Significant differences were seen, however, in the blood and trigeminal ganglia: HSV-1 seroprevalence was observed in females, with no virus detected in males. In brain dissections, only the cerebral cortex of the females had viral loads statistically higher than those observed in the males. The spread of the virus to several organs of interest during acute infection was examined immunohistochemically. Female mice showed greater viral immunostaining, especially in the adrenal cortex, gonads, and midbrain. In male mice, HSV-1 was detected predominantly in the adrenal cortex. It was also found that apolipoprotein E promotes virus colonization of the ovaries, the APOE gene dose being directly related to viral invasiveness.
Journal of Virology 03/2005; 79(3):1605-12. · 5.40 Impact Factor
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ABSTRACT: So far there have been no reports on the expression pattern of DAX-1 (dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1) in human breast cells and its relationship to the estrogen receptors, ER-alpha and ER-beta, and the androgen receptor (AR).
In this study we evaluated, by immunohistochemistry and Western blot analysis, the presence and distribution of DAX-1 in benign breast disease (BBD), in situ carcinoma (CIS), and ductal and lobular breast carcinomas.
In BBD and breast carcinomas, DAX-1 was present in both the nuclei and the cytoplasm of epithelial cells, although in infiltrative carcinomas the percentage of nuclear immunoreaction was higher than in CIS. An important relation was observed between DAX-1 and AR expression and between this orphan receptor and nodal status.
DAX-1 might modify the AR and ER-beta intracellular location, and because a direct positive relation between the expression of these three receptors was found it could be assumed that the presence of DAX-1 in neoplastic cells might indicate a possible failure of endocrine therapies.
Breast cancer research: BCR 02/2004; 6(3):R140-8. · 5.24 Impact Factor
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ABSTRACT: p53, p21, and Rb are proteins with an important role in cell-cycle control. The expression and distribution of these gene products and the apoptotic rate were studied in the marbled-newt testis along the annual cycle to know the role of these factors in the control of spermatogenesis and glandular tissue formation. The study was carried out using Western blot analysis and immunohistochemistry. The results differed from those, previously reported in mammals showing constant spermatogenesis. Greater expression of p53 and p21 was found in the quiescence period and was detected in PCGs (primordial germ cells), spermatogonia, follicular, interstitial cells, and glandular tissue. Greater expression of Rb and phosph-Rb was present in the proliferation period, in PCGs, and spermatogonia. Apoptosis was only detected in secondary spermatogonia (quiescence and spermiogenesis periods) and primary spermatocytes (proliferation and spermiogenesis periods). In the quiescence period, the increase in p53 expression activates p21 expression, which inhibits Rb phosphorylation and arrests the cell cycle in G1. In the proliferation period and, in a lesser degree, in the spermiogenesis period, the expressions of p53 and p21 decrease and phosph-Rb increases, enhancing cell proliferation. These gene products do not seem to be related to apoptosis.
Molecular Reproduction and Development 11/2002; 63(2):202-9. · 2.53 Impact Factor
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ABSTRACT: The aim of this study was to evaluate the presence and distribution of retinoid X receptors (RXRs) alpha, beta, and gamma in normal, hyperplastic (nodular, basal cell, and atrophic hyperplasia), and carcinomatous human prostates in order to elucidate the relationship among these receptors and the onset and development of prostatic adenocarcinoma. RXRalpha and RXRgamma were immunodetected in all samples of normal, nodular, and basal cell hyperplasia, as well as carcinomatous prostates. In atrophic glands, the expression of both receptors was found in 22.5% of samples. Positive immunostaining for RXRbeta was observed in 53.3% of normal prostates, 100% of samples showed basal cell hyperplasia, and were negative in nodular and atrophic hyperplasia. In prostatic adenocarcinoma, only 3 of 25 samples (the 3 diagnosed as well-differentiated) were positive for RXRbeta. Results suggest that diminished RXRbeta expression might be related to prostate cancer progression and because the responsiveness to retinoic acid treatments depends on the expression of different receptors, it is important to study their expression before therapy.
Journal of Andrology 24(1):113-9. · 2.97 Impact Factor
