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The aim of this study was to develop a rabbit neurosphere culture to characterize differences in basic processes of neurogenesis induced by intrauterine growth restriction (IUGR). A novel in vitro neurosphere culture has been established using fresh or frozen neural progenitor cells from newborn (PND0) rabbit brains. After surgical IUGR induction in pregnant rabbits and cesarean section 5 days later, neural progenitor cells from both control and IUGR groups were isolated and directly cultured or frozen at −80°C. These neural progenitor cells spontaneously formed neurospheres after 7 days in culture. The ability of control and IUGR neurospheres to migrate, proliferate, differentiate to neurons, astrocytes, or oligodendrocytes was compared and the possibility to modulate their responses was tested by exposure to several positive and negative controls. Neurospheres obtained from IUGR brains have a significant impairment in oligodendrocyte differentiation, whereas no significant differences are observed in other basic processes of neurogenesis. This impairment can be reverted by in vitro exposure of IUGR neurospheres to thyroid hormone, which is known to play an essential role in white matter maturation in vivo. Our new rabbit neurosphere model and the results of this study open the possibility to test several substances in vitro as neuroprotective candidates against IUGR induced neurodevelopmental damage while decreasing the number of animals and resources and allowing a more mechanistic approach at a cellular functional level., Rabbit “Neurosphere Assay.” PND0 rabbit brains are dissected and either frozen or directly cultured until neurosphere formation. “Neurosphere Assay” starts when neurospheres are plated in 8‐chamber slides and maintained under differentiating conditions to evaluate migration and differentiation into neurons, into astrocytes or into oligodendrocytes. Neurospheres were also plated in 96‐well plates under proliferating conditions and evaluated for diameter increase.

The increasing use of illegal drugs by pregnant women causes a public health concern because it is associated with health risks for mothers and their developing children. One of such drugs is MDMA (3,4-methylenedioxymethamphetamine) or ecstasy due to its high consumption in relevant age and sex groups and its adverse effects on human and rodent developing brains. To Journal Pre-proof 2 thoroughly review the current knowledge on the developmentally neurotoxic potential of MDMA we systematically collected and summarized articles investigating developmental neurotoxicity (DNT) of MDMA in humans and animals in in vivo and in vitro. In addition, we summarized the findings in a putative adverse outcome pathway (AOP). From an initial 299 articles retrieved from the bibliographic databases Web of Science, PubMed and DART, we selected 39 articles according to inclusion/exclusion criteria for data collection after title/abstract and full text screening. Of these 3 where epidemiological studies, 34 where in vivo studies in mice and rats and 2 were in vitro studies. The three epidemiological studies reported from the same longitudinal study and suggested that MDMA exposure during pregnancy impairs neuromotor function in infants. In rat, postnatal exposure towards MDMA also caused locomotor deficits as well as impaired spatial learning that might be associated with decreased serotonin levels in the hippocampus. In vitro MDMA caused cytotoxicity at high concentrations and effects on the serotonergic and neuritogenic alterations at lower concentrations which are in line with some of the in vivo alterations observed. Considering the adverse outcomes of developmental MDMA described in humans and in rodents we summarized the first putative AOP on developmental compound exposure leading to impaired neuromotor function in children. For generation of this AOP, MDMA exposure was taken as a model compound. In addition, we hypothesized a second AOP involving developmental disturbance of the dopaminergic system. However, further in vitro mechanistic studies are needed to understand the molecular initiating event(s) (MIE) triggering the downstream cascades and obtain consistent evidences causally linking the adverse outcome to effects at the cellular, organ and organism level.

Epigallocatechin gallate (EGCG), the main catechin of green tea, is described to have potential health benefits in several fields like oncology, neurology or cardiology. Currently, it is also under pre-clinical investigation as a potential therapeutic or preventive treatment during pregnancy against developmental adverse effects induced by toxic substances. However, the safety of EGCG during pregnancy is unclear due to its proven adverse effects on neural progenitor cells' (NPCs) migration. As lately several strategies have arisen to generate new therapeutic agents derived from EGCG, we have used the rat ‘Neurosphere Assay’ to characterize and compare the effects of EGCG structurally related compounds and EGCG PEGylated PLGA nanoparticles on a neurodevelopmental key event: NPCs migration. Compounds structurally-related to EGCG induce the same pattern of NPCs migration alterations (decreased migration distance, decreased formation of migration corona, chaotic orientation of cellular processes and decreased migration of neurons at higher concentrations). The potency of the compounds does not depend on the number of galloyl groups, and small structure variations can imply large potency differences. Due to their lower toxicity observed in vitro in NPCs, 4,4′-bis[(3,4,5-trihydroxybenzoyl)oxy]-1,1′-biphenyl and EGCG PEGylated PLGA nanoparticles are suggested as potential future therapeutic or preventive alternatives to EGCG during prenatal period.

Human microsomal epoxide hydrolase (mEH) catalyzes a key step in the biotransformation of benzo[a]pyrene that yields the highly mutagenic (+)-anti-7,8-diol-9,10 epoxide (BPDE). Two polymorphisms have been described in the coding region of the mEH gene (EPHX1) that produce two protein variants: 113Tyr-->113His (exon 3) and 139His-->139Arg (exon 4). We performed a case-control study among Northwestern Mediterranean Caucasians to investigate a possible association between these EPHX1 variants and lung cancer risk. Both EPHX1 polymorphisms were analyzed in a group of lung cancer patients (n=176) and in a control group of healthy smokers (n=187). The results showed a significantly decreased risk for the rare homozygous 113His/113His (adjusted odds ratio (OR): 0.44, 95% confidence interval (CI): 0.27-0.71) and 139Arg/139Arg (adjusted OR: 0.55, 95% CI: 0.33-0.91) compared with the major wild-types 113Tyr/113Tyr and 139His/139His, respectively, as the references. Thereafter, we analyzed the EPHX1 variants in combination with three glutathione S-transferase polymorphic genes (GSTM1, GSTT1, and GSTP1) and we found a significant overepresentation of cancer patients with a combination of exon 3 113Tyr/113Tyr EPHX1 and exon 5 105Ile/105Ile GSTP1 (adjusted OR: 2.34, 95% CI: 1.21-4.52). The polymorphic site within the exon 5 of GSTP1 results in a Ile-->Val substitution, and the isoleucine GSTpi isoform has been found in vitro to be less active than the valine isoform towards the conjugation of BPDE. The 113 Tyr/Tyr EPHX1 encodes for a high-activity mEH. Our results agree with these observations in vitro and suggest that a genetically determined combination of a high-activity mEH and a low-activity GSTpi may increase lung cancer risk among smokers.

10.1016/j.fct.2011.06.077 The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), as well as those of 18 polychlorinated biphenyls (PCBs), including 12-dioxin like (DL)-PCBs, were measured in foodstuffs randomly acquired in Catalonia (Spain) in November-December 2008. A total of 65 composite samples, belonging to various food groups were analyzed by HRGC/HRMS. The dietary intakes of PCDD/Fs and PCBs were subsequently estimated for four age groups of the population of Catalonia: children, teenagers, adults, and seniors, which were in turn divided according to sex. The highest dietary exposure to PCDD/Fs corresponded to fish and seafood (28.0%), dairy products (15.4%), and oils and fats (10.6%), while that of PCBs corresponded to fish and seafood (58.6%), and dairy products (8.9%). In contrast, the lowest contributions of PCDD/Fs and PCBs corresponded to vegetables, fruits and pulses. Concerning the sum of PCDD/Fs plus DL-PCBs, the current total intake expressed in pg WHO-TEQ/kg per day (0.60) showed a notable decreasing trend with respect to those found in previous surveys performed also in Catalonia in 2000 (3.51) and 2006 (1.12pg/kg per day). The current dietary intake of PCDDs plus DL-PCBs is similar or lower than that recently reported in studies performed in a number of regions and countries.

3,4-Methylenedioxymethamphetamine, MDMA or "ecstasy" is consumed mainly by young population at childbearing age. Therefore, there may be a risk of exposure of some pregnant women. The effects of the developmental exposure to MDMA on the sexual development and long-term sexual behaviour/fertility were assessed in Sprague-Dawley rats. MDMA was administered subcutaneously at 0 (control), 0.5, 5 and 10 mg/kg to female rats once a day, three consecutive days a week during 10 weeks, including gestation and lactation. The male offspring was evaluated for sexual maturation and mated with untreated sexually receptive females to evaluate the mating and pregnancy rates. Hormonal, haematological, biochemical, histological, genotoxicological and testicular and sperm parameters were also evaluated. A significant higher incidence of DNA damage in sperm and interstitial oedema in testes was found. There was also a significant and dose-related decrease in sperm count and a significant decrease in sperm motility at all doses. A significant delay in preputial separation onset in all treated groups was observed. This study reports by the first time an alteration of spermatogenesis after in utero and lactation MDMA exposure in the rat.

3,4-Methylenedioxymethamphetamine (MDMA or "ecstasy") is consumed mainly by young population. For this reason, it is especially relevant to take into consideration the effects on the reproductive system. The influence of MDMA on the fertility and reproduction of the male rat was assessed in this study. MDMA was administered subcutaneously at 0 mg/kg (control), 0.5 mg/kg, 5 mg/kg and 10 mg/kg to SD male rats once a day, 3 consecutive days a week during 12 weeks, simulating human weekend associated consumption. Hormonal, haematological, biochemical, histological, genotoxicological and testicular and sperm parameters were evaluated in half of the rats. The remaining animals were mated with untreated sexually receptive females to evaluate the mating and pregnancy rates. A significantly higher incidence of DNA damage in Comet Test in sperm, tubular degeneration and interstitial oedema in testes was found. At all doses tested, sperm motility, morphology, mating and pregnancy rates, and number of implantation sites were not affected. This study fills the existing gap of knowledge about the chronic effects of MDMA in reproductive function using a realistic experimental design. Taking into account the higher sensitivity of human males, some concerns about the effects on the reproductive health still remain.

Polychlorinated biphenyls (PCBs) are a class of aryl halides widely distributed in the environment. Although production has virtually ceased, and most industrial applications (capacitors, transformers, hydraulic fluids, lubricants, etc) are severely restricted, they are one of the most ubiquitous and persistent environmental pollutants. Several toxic effects caused by PCBs have been described including: liver enlargement, hepatomegalocytosis, acne, lymphoid atrophy, immunosuppression, tumor promotion, porphyria, etc (Reggiani, 1982; McConneU, 1980). This work continues our previous reports about organochlorine residues in human tissues of some Spanish populations, that showed high levels of some residues, specially of hexachlorobenzene (HCB) (To-Figueras et al, 1986; Camps et al, 1988). PCBs pattern and concentration in the adipose tissue of the inhabitants of an urban and industrial area (Barcelona) were determined.

Two polymorphic sites of the microsomal epoxide hydrolase gene (EPHX1, 113Tyr--113His, 139His--139Arg) and four glutathione S-transferase genes (GSTM1, GSTM3, GSTP1, GSTT1) were genotyped in a group of patients with larynx cancer (N=204) and in a group of healthy controls (N=203), all Spanish caucasians. After adjusting for gender, age, and tobacco smoking, none of the polymorphisms alone were found to be associated with larynx cancer risk. The analysis of EPHX1/GST combinations, however, showed a significant over-representation of patients with a combination of 113Tyr/113Tyr EPHX1 and 105Ile/105Ile GSTP1 (adjusted odds ratio (OR): 1.95; 95% confidence interval (CI): 1.02-3.78). The calculation of the predicted epoxide hydrolase (EH) activity also showed an increased risk for the individuals with both predicted high activity EH and 105Ile/105Ile GSTP1 (OR: 2.90; 95% CI: 1.10-7.67). These results on larynx cancer tend to confirm a former study on lung cancer (Cancer Lett. 173 (2001) 155) suggesting the existence of an interaction between variants of EH and GSTpi, both enzymes being involved in the metabolism of aromatic hydrocarbons, that may increase susceptibility to tobacco-related cancers.

Pentachlorothiophenol, a sulphur derivative of the widespread environmental pollutant hexachlorobenzene (HCB) has been detected and quantified in the urine of a human general population with high body burden of HCB. The sulphur derivative was analysed by GLC-MS as pentachlorothioanisole (PCTA) after hydrolysis and methylation of the respective conjugate and was found in 100% of the samples ( n = 40) with a mean concentration of 1.85 ± 0.98 ng ml-1 (X ± s.d., range 0.58-4.50 ng ml-1). No correlation with urinary pentachlorophenol (PCP) and no sex-related differences were found. The derivative may originate from the biotransformation of HCB stored in tissues and may be a useful maker of HCB metabolism in humans.

blood donors from the general population (n 5 192). All patients and controls were Northwestern Mediterranean controversial since the initial phenotyping studies showed a Caucasians. The results show that the GSTM1 null genotype clear association between class μ GST deficiency and lung (GSTM1*0/GSTM1*0) was slightly over represented in the cancer risk (5,6) but the later genotyping studies have shown lung cancer patients (frequency of 58%; OR: 1.40, 95% discrepant results (12,13). Furthermore, some studies on CI: 0.74‐2.61, referred to healthy smokers). The histological bladder cancer have suggested that the possible protective type most clearly modified was small cell carcinoma (fre- effect of the alleles GSTM1*A and GSTM1*B may not be quency of 62.2%, OR: 1.91, CI: 0.78‐4.69). The subdivision identical (14) whereas others have found that GSTM1*A/B of the patients with one or two copies of the GSTM1 heterozygosity, but not GSTM1*Aor GSTM1*B, was protective gene according to a GSTM1*A, GSTM1*B or GSTM1*A/B among skin cancer patients with multiple basal cell carcinomas genotype (frequencies of 28.2 %, 11.2%, 2.5% respectively) (11). This has lead some authors to suggest that a model based revealed no significant differences between the cases and on the hypothesis that GSTM1*0 alone confers increased risk both control groups. The frequency of the deleted GSTT1 may be too simplistic and that the role of the different GSTM1 genotype among the lung cancer patients (24%) was not alleles and of other genes of the same family such as GSTM3 significantly increased (OR: 1.08, CI: 0.57‐2.05, referred should be taken into account (15). to healthy smokers). The results showed that 14.4% of the Another polymorphic gene of the same family is GSTT1 patients presented homozygous deletion of both GSTT1 which encodes for a class θ GST that catalyzes the conjugation and GSTM1 (12.5% among healthy smokers) suggesting of halomethanes in human erythrocytes (16,17). Substrates of no potentiation between null genotypes for lung cancer risk. θ GST include industrial chemicals such as methyl chloride, methyl bromide, dichloromethane, ethylene oxide and diepoxybutane, a reactive metabolite of 1,3-butadiene. Indi

The appearance of sex-related differences in the excretion of sulphur derivatives of hexachlorobenzene (HCB) and pentachloronitrobenzene (PCNB) was studied in vitro and in vivo. Sexually immature rats given HCB showed initially no differences in the excretion of N -acetyl- S -(pentachlorophenyl)cysteine, but 5–8 days after weaning the urinary levels of the sulphur derivative began to increase in females until a 10-fold difference between both sexes was established. The studies in vitro and the analysis of tissues after in vivo administration of PCNB showed that conjugation with glutathione and hydrolysis of the conjugates to yield free pentachlorothiophenol do not present sex-related differences. These data tend to reinforce the view that an active renal secretory mechanism probably induced by estrogens during sexual maturation is responsible for the highly efficient excretion of sulphur derivatives of HCB and PCNB by female rats.

Organochlorine residues (OCR)2 are poorly soluble in water and are transported in the organism bound by the blood components. The distribution among blood fractions (cells/plasma, lipoproteins/rest of plasma proteins) were variable depending on the residue (HCB, p p'-DDE, HCH, Aroclor 1260, PCP) and on the species (rat, man). Differences were not found between in vivo (after oral single dosing) and in vitro (blood incubation) experiments. Results indicated a high affinity of organochlorine residues for lipoproteins; however, binding to blood carriers was very weak as demonstrated by the rapid release of residues by elution through a reverse phase column. The effects of residue binding to blood components on the distribution kinetics to tissues are discussed.

The environmental pollution by persistent organochlorine residues has received much attention in the last years because of its possible effects on wildlife and human health. These residues - organochlorine insecticides, hexa-chlorobenzene (HCB), polychlorinated biphenyls (PCBs) and, in minor levels, polychlorinated dibenzofurans (PCDFs) and dibenzodioxins (PCDDs) - are accumulated in lipid-rich tissues. Their concentrations in adipose tissues of human populations are the best indices in determining the extent of exposure and in evaluating the hazard. In a previous study on the urban population of Barcelona (Spain) during the years 1982-83, high levels of DDE, DDT, /beta/-HCH and HCB were determined. Recently the incidence of HCB in Barcelona has been confirmed by serum determinations. In the present paper the authors have investigated the levels of organochlorine residues - with special concern on HCB- in human adipose tissues from an agrarian area, located at 130 km from Barcelona, mainly devoted to fruit-trees and cereal culture. Results obtained will form part of an up-to-date report on organochlorine pollution in Spain, including several populations of different geographical and socioeconomic characteristics, that will make it possible to identify the sources and trends of this contamination.

Hexachlorobenzene (HCB) and p , p ′-dichlorodiphenyldichloroethylene ( p , p ′-DDE) kinetics were compared in rats before, during and after partial starvation. Food restriction produced a drastic mobilization of the residues stored in the adipose tissue resulting in symptoms of neurotoxicity. The redistribution was reversible and did not produce a significant reduction in the chemicals body burden. HCB and p , p ′-DDE, although both highly lipophilic, showed important differences in their blood transport and distribution pattern, with more HCB being transported by red blood cells and with a greater facility for HCB to reach the liver and the brain.