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Clinical and animal studies have reported an association between low birth weight and the development of nonalcoholic fatty liver disease (NAFLD) in offspring. Using a model of prenatal maternal 70% food restriction diet (FR30) in the rat, we previously showed that maternal undernutrition predisposes offspring to altered lipid metabolism in adipose tissue, especially on a high-fat (HF) diet. Here, using microarray-based expression profiling combined with metabolic, endocrine, biochemical, histological, and lipidomic approaches, we assessed whether FR30 procedure sensitizes adult male offspring to impaired lipid metabolism in the liver. No obvious differences were noted in the concentrations of triglycerides, cholesterol, and bile acids in the liver of 4-mo-old FR30 rats whichever postweaning diet was used. However, several clues suggest that offspring’s lipid metabolism and steatosis are modified by maternal undernutrition. First, lipid composition was changed (i.e., higher total saturated fatty acids and lower elaidic acid) in the liver, whereas larger triglyceride droplets were observed in hepatocytes of undernourished rats. Second, FR30 offspring exhibited long-term impact on hepatic gene expression and lipid metabolism pathways on a chow diet. Although the transcriptome profile was globally modified by maternal undernutrition, cholesterol and bile acid biosynthesis pathways appear to be key targets, indicating that FR30 animals were predisposed to impaired hepatic cholesterol metabolism. Third, the FR30 protocol markedly modifies hepatic gene transcription profiles in undernourished offspring in response to postweaning HF. Overall, FR30 offspring may exhibit impaired metabolic flexibility, which does not enable them to properly cope with postweaning nutritional challenges influencing the development of nonalcoholic fatty liver.

Objective According to the Developmental Origin of Health and Disease (DOHaD) concept, maternal obesity and accelerated growth in neonates predispose offspring to white adipose tissue (WAT) accumulation. In rodents, adipogenesis mainly develops during lactation. The mechanisms underlying the phenomenon known as developmental programming remain elusive. We previously reported that adult rat offspring from high-fat diet-fed dams (called HF) exhibited hypertrophic adipocyte, hyperleptinemia and increased leptin mRNA levels in a depot-specific manner. We hypothesized that leptin upregulation occurs via epigenetic malprogramming, which takes place early during development of WAT. Methods As a first step, we identified in silico two potential enhancers located upstream and downstream of the leptin transcription start site that exhibit strong dynamic epigenomic remodeling during adipocyte differentiation. We then focused on epigenetic modifications (methylation, hydroxymethylation, and histone modifications) of the promoter and the two potential enhancers regulating leptin gene expression in perirenal (pWAT) and inguinal (iWAT) fat pads of HF offspring during lactation (postnatal days 12 (PND12) and 21 (PND21)) and in adulthood. Results PND12 is an active period for epigenomic remodeling in both deposits especially in the upstream enhancer, consistent with leptin gene induction during adipogenesis. Unlike iWAT, some of these epigenetic marks were still observable in pWAT of weaned HF offspring. Retained marks were only visible in pWAT of 9-month-old HF rats that showed a persistent “expandable” phenotype. Conclusions Consistent with the DOHaD hypothesis, persistent epigenetic remodeling occurs at regulatory regions especially within intergenic sequences, linked to higher leptin gene expression in adult HF offspring in a depot-specific manner., Highlights • The white adipose tissue is an important target of developmental programming. • Higher leptin gene expression occurs in offspring from obese dams in a depot-specific manner. • Leptin upregulation occurs via epigenetic malprogramming during development of adipose tissue. • Persistent genomic epigenetic remodeling occurs in adipose tissue of offspring from obese dams. • Intergenic regions were more affected than the leptin promoter region in offspring of obese dams.

National audience; As stated by the Developmental Origin of Health and Disease (DOHaD) concept, alterations of nutrient supply in the fetus or neonate result in long-term conditioning of individual body weight set-point. In particular, maternal obesity, excessive nutrition and accelerated growth in neonates have been shown ta sensitize offspring to obesity and metabolic disturbances. The white adipose tissue (WAT), which develops mainly during lactation in rodents, may represent a prime target of metabolic programming. In order to unravel the unclerlying mechanisms, we have developed a rat model of maternal obesity using a high-fat (HF) diet before and during gestation and lactation. At weaning, offspring from obese clams were fed a standard diet until adulthood. We hypothesize that maternal obesity impairs epigenetic mechanisms and alters offspring's WAT. These modifications might be persistent and have long-term effects on the ex­ pression of adipogenic and lipogenic genes predisposing HF offspring ta fat accumulation. Inthis study, we focused on epigenetic modifications of the leptin gene promoter in WAT of offspring at two stages of lactation (postnatal days 12 (PND12) and 21 (PND21)) and in adulthood (9 months). At birth, newborns from obese clams (callecl HF) were normotrophs. From PND12 ta PND21, HF offspring exhibited a strong increase in adiposity. Higher body weight (+303) observed at weaning persists until 3 months of age. Despite no difference in body weight and energy intake, adult HF offspring showed fat accumulation, glucose intolerance and hyperinsulinemia. During lactation, the expansion of WAT correlatecl with increases in both adipocyte size and number in most depots. The adipose phenotype was still observable in 9-month-olc\ HF offspring. Ma­ ternal obesity led ta markecl changes in adipogenic (PREF-1, C/EBPa, PPARg) and lipogenic (DGAT2, SREBP-1, FAS, leptin) gene expression in WAT of HF adult offspring. In particular, leptin mRNA content was increased in HF offspring in different fat depots at three different stages of development. This is in agreement with persistent elevated plasma leptin levels in HF offspring from weaning ta adulthood. The increased expression of leptin was associated with an enrichment of the acetylation of histone H3, despite an increase of methylation across the promoter region in HF offspring al PND12, PND21 and 9 months of age. Taken together, we showecl that maternal obesity leads ta higher expansion capacity (i.e., hy­ pertrophy and hyperplasia) of offspring's WAT. Increased WAT cellularity was associated with hyperleptinemia and elevated levels of leptin gene expression in HF offspring throughout life. Persistent increased levels of leptin gene expression occur, al least in part, via epigenetic mechanisms which may take place during the early postnatal period.

Epidemiological and experimental data indicate that maternal undernutrition may sensitize the offspring to the apparition of chronic diseases such as metabolic syndrome and schizophrenia, suggesting that these pathologies may have a developmental origin. To test this hypothesis, we have compared the effects of a 4 weeks treatment of clozapine (30 mg/kg once daily, p.o.) or aripiprazole (10 mg/kg once daily, p.o.) on metabolic and hormonal parameters in 4-month-old male animals from control or 70% prenatally food-restricted mothers (FR30 model). Both neuroleptics did not markedly modify body weight gain and food intake in both controls and FR30 rats. Clozapine decreased insulin secretion in both groups but significantly diminished leptin, corticosterone and glucose plasma levels only in FR30 animals. Aripiprazole decreased corticosterone plasma levels only in FR30 animals. Using quantitative RT-PCR array containing 84 obesity-related genes, we identified several genes involved in energy metabolism regulation whose expression was modified by clozapine or aripiprazole in adult male rat hypothalami. In addition, we demonstrated that expression of some of these genes was differentially affected by each neuroleptic in the hypothalamus of both FR30 and control animals. Although no marked metabolic alterations were observed in both control and FR30 animals after clozapine or aripiprazole treatment, our data indicate that offspring from undernourished mothers exhibit a modified sensitivity to atypical neuroleptics. Our results do not rule out a putative developmental origin of schizophrenia and may help to understand the way by which atypical neuroleptics, such as clozapine, sensitize schizophrenic patients to the development of metabolic disorders.

Several studies have shown that maternal undernutrition leading to low birth weight predisposes offspring to the development of metabolic pathologies such as obesity. Using a model of prenatal maternal 70% food restriction diet (FR30) in rat, we evaluated whether postweaning high-fat (HF) diet would amplify the phenotype observed under standard diet. We investigated biological parameters as well as gene expression profile focusing on white adipose tissues (WAT) of adult offspring. FR30 procedure does not worsen the metabolic syndrome features induced by HF diet. However, FR30HF rats displayed catch-up growth to match the body weight of adult control HF animals, suggesting an increase of adiposity while showing hyperleptinemia and a blunted increase of corticosterone. Using quantitative RT-PCR array, we demonstrated that FR30HF rats exhibited leptin and Ob-Rb as well as many peptide precursor and receptor gene expression variations in WAT. We also showed that the expression of genes involved in adipogenesis was modified in FR30HF animals in a depot-specific manner. We observed an opposite variation of STAT3 phosphorylation levels, suggesting that leptin sensitivity is modified in WAT adult FR30 offspring. We demonstrated that 11β-HSD1, 11β-HSD2, GR, and MR genes are coexpressed in WAT and that FR30 procedure modifies gene expression levels, especially under HF diet. In particular, level variation of 11β-HSD2, whose protein expression was detected by Western blotting, may represent a novel mechanism that may affect WAT glucocorticoid sensitivity. Data suggest that maternal undernutrition differently programs the adult offspring WAT gene expression profile that may predispose for altered fat deposition.

Several studies indicate that maternal undernutrition sensitizes the offspring to the development of metabolic disorders, such as obesity. Using a model of perinatal maternal 50% food-restricted diet (FR50), we recently reported that rat neonates from undernourished mothers exhibit decreased leptin plasma levels associated with alterations of hypothalamic proopiomelanocortin system. The present study aimed at examining the consequences of FR50 on the brain-adipose axis in male rat neonates. Using quantitative RT-PCR array containing 84 obesity-related genes, we demonstrated that most of the genes involved in energy metabolism regulation are expressed in rat gonadal white adipose tissue (WAT) and are sensitive to maternal perinatal undernutrition (MPU). In contrast, hypothalamic gene expression was not substantially affected by MPU. Gene expression of uncoupling protein 1 (UCP1), a marker of brown adipocytes, showed an almost 400-fold stimulation in postnatal day 21 (PND21) FR50 animals, suggesting that their gonadal WAT possesses a brown-like phenotype. This was confirmed by histological and immunoshistochemical procedures, which demonstrated that PND21 FR50 gonadal adipocytes are multilocular, resembling those present in interscapular brown adipose tissue, and exhibit an overexpression of UCP1 and neuropeptide Y (NPY) at the protein level. Control animals contained almost exclusively “classical” unilocular white adipocytes that did not show high UCP1 and NPY labeling. After weaning, FR50 animals exhibited a transient hyperphagia that was associated with the disappearance of brown-like fat pads in PND30 WAT. Our results demonstrate that MPU delays the maturation of gonadal WAT during critical developmental time windows, suggesting that it could have long-term consequences on body weight regulation in the offspring.

Maternal perinatal undernutrition (MPU) modifies the activity of the hypothalamic-pituitary-adrenal axis and sensitises to the development of metabolic and cognitive adult diseases. Because the hypothalamus and hippocampus are involved in the regulation of neuroendocrine activity, energy metabolism and cognition, we hypothesised that a maternal 50% food restriction (FR50) from day 14 of pregnancy (E14) until postnatal day 21 (P21) would affect the development of these structures in male rat offspring. Protein and mRNA levels of brain-derived neurotrophic factor (BDNF) and cell proliferation [analysed by 5-bromodeoxyuridine (BrdU) incorporation] were compared in both control and FR50 rats from E21 to P22. Although the pattern of the evolution of BDNF concentration and cell proliferation throughout development was not strikingly different between groups, several disturbances at specific developmental stages were observed. FR50 rats exhibited a delayed increase of hippocampal BDNF content whereas, in the hypothalamus, BDNF level was augmented from E21 to P14 and associated, at this latter stage, with an increased mRNA expression of TRkB-T2. In both groups, a correlation between BDNF content and the number of BrdU positive cells was noted in the dentate gyrus, whereas opposite variations were observed in CA1, CA2 and CA3 layers, and in the arcuate and ventromedial nuclei. In the hippocampus, P15-FR50 rats showed an increased number of BrdU positive cells in all regions, whereas, at P22, a decrease was observed in the CA2. In the hypothalamus, between E21 and P8, MPU increases the number of BrdU positive cells in all regions analysed and, until P15, marked differences were noticed in the median eminence, the paraventricular nucleus and the arcuate nucleus. Taken together, the results obtained in the present study show that MPU changes the time course of production of BDNF and cell proliferation in specific hippocampal and hypothalamic areas during sensitive developmental windows, suggesting that these early perinatal modifications may have long-lasting consequences .

Maternal undernutrition leads to intrauterine growth retardation and predisposes to the development of pathologies in adulthood. The hypothalamo-pituitary-adrenal axis is a major target of early-life programming. We showed previously that perinatal maternal 50% food restriction leads to hypothalamo-pituitary-adrenal axis hyperactivity and disturbs glucocorticoid feedback in adult male rats. To try to better understand these alterations, we studied several factors involved in corticosterone sensitivity. We showed that unlike the restricted expression of 11 beta-HSD2 mRNA, the 11 beta-HSD1, glucocorticoid, and mineralocorticoid receptor genes are widely distributed in rat. In contrast to the hypothalamus, we confirmed that maternal undernutrition modulates hippocampal corticosterone receptor balance and leads to increased 11 beta-HSD1 gene expression. In the pituitary, rats exhibited a huge increase in both mRNA and mineralocorticoid receptor binding capacities as well as decreased 11 beta-HSD1/11 beta-HSD2 gene expression. Using IN SITU hybridization, we showed that the mineralocorticoid receptor gene was expressed in rat corticotroph cells and by other adenopituitary cells. In the adrenal gland, maternal food restriction decreased 11beta-HSD2 mRNA. This study demonstrated that maternal food restriction has both long-term and tissue-specific effects on gene expression of factors involved in glucocorticoid sensitivity and that it could contribute, via glucocorticoid excess, to the development of adult diseases.

Undernutrition exposure during the perinatal period reduces the growth kinetic of the offspring and sensitizes it to the development of chronic adult metabolic diseases both in animals and in humans. Previous studies have demonstrated that a 50% maternal food restriction performed during the last week of gestation and during lactation has both short- and long-term consequences in the male rat offspring. Pups from undernourished mothers present a decreased intrauterine (IUGR) and extrauterine growth restriction. This is associated with a drastic reduction in their leptin plasma levels during lactation, and exhibit programming of their stress neuroendocrine systems (corticotroph axis and sympatho-adrenal system) in adulthood. In this study, we report that perinatally undernourished 6-month-old adult animals demonstrated increased leptinemia (at PND200), blood pressure (at PND180), food intake (from PND28 to PND168), locomotor activity (PND187) and altered regulation of glycemia (PND193). Cross-fostering experiments indicate that these alterations were prevented in IUGR offspring nursed by control mothers during lactation. Interestingly, the nutritional status of mothers during lactation (ad libitum feeding v. undernutrition) dictates the leptin plasma levels in pups, consistent with decreased leptin concentration in the milk of mothers subjected to perinatal undernutrition. As it has been reported that postnatal leptin levels in rodent neonates may have long-term metabolic consequences, restoration of plasma leptin levels in pups during lactation may contribute to the beneficial effects of cross-fostering IUGR offspring to control mothers. Collectively, our data suggest that modification of milk components may offer new therapeutic perspectives to prevent the programming of adult diseases in offspring from perinatally undernourished mothers.

Introduction et but de l’etude Le concept de l’origine developpe-mentale des maladies (DOHaD) stipule qu’un environnement deletere, incluant une malnutrition maternelle, in utero ou en periode postnatale precoce predispose la descendance a l’âge adulte au developpement d’un syndrome metabolique (diabete de type 2, hypertension et obesite). En particulier, des etudes epidemiologiques chez l’homme et experimentales chez l’animal ont montre que l’obesite maternelle, la surnutrition des nouveau-nes et la croissance postnatale acceleree sensibilisent la descendance a l’adiposite. Le but de notre etude est d’etudier les mecanismes de programmation du tissu adipeux blanc (TAB) chez la descendance mâle issue de meres surnutries. Materiel et methodes Nous avons developpe un modele de surnutrition maternelle chez le rat en alimentant des femelles puberes avec un regime hypercalorique hyperlipidique (60 % de lipides (Kcal)) pendant 4 mois avant la conception, pendant la gestation et la lactation. Au sevrage, la descendance mâle issue de meres surnutries a ete placee sous regime standard jusqu’a l’âge de 9 mois. La caracterisation de la descendance durant cette periode a ete effectuee a l’aide d’approches complementaires physiologiques (suivi des parametres metaboliques, dosages hormonaux par ELISA), moleculaires (RT-PCR quantitative) et histologiques (microscopie optique). Resultats et Analyse statistique Un regime maternel hypercalorique hyperlipidique ne modifie pas le poids de naissance. Cependant, il accelere la croissance postnatale et augmente la masse ponderale de la progeniture au cours de la lactation (periode maximale de l’adipogenese) suggerant un accroissement du tissu adipeux. Des l’âge de 3 mois, les rats mâles issus de meres surnutries ne montrent plus de difference de masse ponderale. A 7 mois, les animaux sont normoglycemiques mais presentent des traits de syndrome metabolique (intolerance au glucose, hyperinsulinemie +21 %, hypercorticosteronemie +89 %). Ils consomment quotidiennement la meme quantite de nourriture que les rats controles, mais leur prise alimentaire au cours du nycthemere est significativement modifiee (augmentation en periode diurne (+176 %) et diminution en periode nocturne). A 9 mois, les rats mâles issus de meres surnutries ne montrent pas de surpoids mais sont predisposes a l’adiposite comme l’atteste l’augmentation de la masse des depots de TAB perigonadique et perirenal (+17 %), du taux de leptine plasmatique (+120 %) et de son niveau d’expression genique adipocytaire (+40 %). De plus, l’analyse histologique montre une hypertrophie globale des adipocytes (+135 %) qui est associee a une augmentation du niveau d’expression genique de facteurs lipogeniques (SREBP-1c +67 %, FAS +50 %) et a une diminution du facteur adi-pogenique PPARg (−29 %). Conclusion En accord avec le concept de programmation precoce des maladies et de la sante, nos resultats confirment que la surnutrition maternelle programme la fonction et l’expansion du TAB de la descendance mâle chez le rat et favorise a l’apparition de troubles metaboliques. En particulier, ces donnees suggerent que la croissance acceleree durant la lactation constituerait un evenement determinant de cette programmation.

Epidemiological studies demonstrated that adverse environmental factors leading to intrauterine growth retardation (IUGR) and low birth weight may predispose individuals to increased risk of metabolic syndrome. In rats, we previously demonstrated that adult male IUGR offspring from prenatal 70% food-restricted dams throughout gestation (FR30) were predisposed to energy balance dysfunctions such as impaired glucose intolerance, hyperleptinemia, hyperphagia and adiposity. We investigated whether postweaning moderate high-fat (HF) diet would amplify the phenotype focusing on the hypothalamus gene expression profile. Prenatally undernourished rat offspring were HF-fed from weaning until adulthood while body weight and food intake were measured. Tissue weights, glucose tolerance and plasma endocrine parameters levels were determined in 4-month-old rats. Hypothalamic gene expression profiling of adult FR30 rat was performed using Illumina microarray analysis and the RatRef-12 Expression BeadChip that contains 21,792 rat genes. Under HF diet, contrary to C animals, FR30 rats displayed increased body weight. However, most of the endocrine disorders observed in chow diet-fed adult FR30 were alleviated. We also observed very few gene expression changes in hypothalamus of FR30 rat. Amongst factors involved in hypothalamic energy homeostasis programming system, only the POMC and transthyretin mRNA expression levels were preferentially increased under HF diet. Both elevated gene expression levels may be seen as adaptive mechanisms counteracting against deleterious effects of HF feeding in FR30 animals. This study shows that the POMC gene expression is a key target of long-term developmental programming in prenatally undernourished male rat offspring, specifically within an obesogenic environment.

Mild gestational hyperglycemia is often associated with fetal overgrowth that can predispose the offspring to metabolic diseases later in life. We hypothesized that unfavorable intrauterine environment may compromise the development of placenta and contribute to fetal overgrowth. Therefore, we developed a rat model and investigated the effects of maternal dysglycemia on fetal growth and placental gene expression. Female rats were treated with single injection of nicotinamide plus streptozotocin (N-STZ) 1-week before mating and were studied at gestational day 21. N-STZ pregnant females displayed impaired glucose tolerance that is associated with a lower insulin secretion. Moderate hyperglycemia induced fetal overgrowth in 40% of newborns, from pregnancies with 10 to 14 pups. The incidence of macrosomia was less than 5% in the N-STZ pregnancies when the litter size exceeds 15 newborns. We found that placental mass and the labyrinthine layer were increased in macrosomic placentas. The expression of genes involved in placental development and nutrient transfer was down regulated in the N-STZ placentas of macrosomic and normosomic pups from pregnancies with 10 to 14 ones. However, we observed that lipoprotein lipase 1 (LPL1) gene expression was significantly increased in the N-STZ placentas of macrosomic pups. In pregnancies with 15 pups or more, the expression of IGFs and glucose transporter genes was also modulated in the control placentas with no additional effect in the N-STZ ones. These data suggest that placental gene expression is modulated by gestational conditions that might disrupt the fetal growth. We described here a new model of maternal glucose intolerance that results in fetal overgrowth. We proposed that over-expression of LPL1 in the placenta may contribute to the increased fetal growth in the N-STZ pregnancies. N-STZ model offers the opportunity to determinate whether these neonatal outcomes may contribute to developmental programming of metabolic diseases in adulthood.

Introduction et but de l’etude Le concept de l’origine developpementale de la sante et des maladies (DOHaD) stipule qu’un environnement perinatal deletere predispose la descendance a l’apparition de troubles metaboliques. En particulier, l’obesite maternelle, la surnutrition des nouveau-nes et la croissance postnatale acceleree sensibilisent la descendance a l’obesite. Le tissu adipeux blanc (TAB) constituerait une cible privilegiee de la programmation perinatale. Cependant, les mecanismes de programmation restent meconnus. Nous posons l’hypothese qu’un environnement maternel obesogene modifierait l’activite enzymatique de la machinerie epigenetique lors de l’ontogenese du TAB. Cela entrainerait la mise en place precoce d’empreintes epigenetiques au niveau de genes cles impliques dans la maturation du TAB conduisant a une modification de leur niveau d’expression. Le maintien de ces marques epigenetiques a l’âge adulte associe a des variations d’expression genique pourrait expliquer, en partie, la predisposition de la descendance a l’adiposite. Materiel et methodes Afin d’etudier les mecanismes sous-jacents a cette programmation, nous avons developpe un modele d’obesite maternelle chez le rat consistant en un regime obesogene (hyperlipidique hypercalorique, 60 % de lipides [kcal]) applique en periode preconceptionnelle, pendant la gestation et la lactation. Les parametres metaboliques, les caracteristiques histologiques et les analyses transcriptionnelles (qPCR) et epigenetiques (ChiP-qPCR) du TAB chez la descendance mâle sont mesures a trois stades differents du developpement chez des animaux âges de 12 (P12) et 21 (P21) jours (periode de lactation) et de 9 mois (âge adulte). Resultats et analyse statistique L’obesite maternelle ne modifie pas le poids de naissance mais accelere la croissance postnatale des nouveau-nes conduisant a un surpoids au sevrage. Ce surpoids developpe au cours de la lactation (periode cle du developpement du TAB chez les rongeurs) est la consequence d’une expansion rapide de ce tissu, caracterise par une hyperplasie et une hypertrophie des adipocytes associees a des alterations de l’expression de genes impliques dans l’adipogenese et la lipogenese. La descendance mâle adulte issue de mere obese conserve une masse de TAB plus importante avec des caracteristiques similaires. Des P12, le TAB des ratons issus de mere obese montrent des variations d’expression de PPARγ et de C/EBPα (genes du developpement adipocytaire) et de la leptine et de l’adiponectine (genes de phenotype adipocytaire). Ces modifications transcriptionnelles sont correlees a des alterations de l’expression d’enzymes de la machinerie epigenetique (HDAC1, DNMT1…). De plus, les promoteurs de ces genes montrent un enrichissement differentiel en histones methyles (H3K4me2, H3K9me2) et/ou acetyles (H4ac, H3ac) temoignant de la mise en place d’empreintes epigenetiques durant cette periode. La cinetique de mise en place et l’etude des marques epigenetiques a l’âge adulte sont en cours d’investigation. Conclusion Nos resultats demontrent que la periode de lactation est le siege de modifications histologiques, transcriptionnelles et epigenetiques chez la descendance de mere obese refletant un developpement precoce et accelere du TAB.

We have previously shown that prenatal morphine exposure inhibited the hypothalamo-pituitary-adrenal (HPA) axis and altered the hypothalamic metabolism of serotonin during the early postnatal period in the rat and induced a chronic sympathoadrenal hyperactivity under resting conditions in adult male rats. In this study, we examined the effects of prenatal morphine exposure on the responsiveness to an acute ether inhalation stress of the sympathoadrenal and HPA axis and the hippocampal and hypothalamic concentrations of serotonin (5HT) and 5-hydroxylindoleacetic acid (5HIAA) in 3-month-old male rats. The plasma levels of adrenocorticopic hormone (ACTH) and corticosterone (B) did not differ between the two groups both under resting conditions and after ether exposure. Ether inhalation increased adrenal tyrosine hydroxylase (TH) and phenylethanolamine N-methyltransferase (PNMT) mRNA expression as well as adrenal epinephrine (E) concentration in control rats but not in prenatally morphine-exposed (PM) animals. Under basal conditions, hypothalamic concentrations of 5HT and 5HIAA increased in PM animals. In contrast to control animals, PM rats showed, in response to stress, an increased level of 5HT and 5HIAA in both the hypothalamus and in the hippocampus. In conclusion, prenatal morphine exposure produces long-lasting alterations in brain serotonin transmission and in the sympathoadrenal responsiveness to an acute systemic stress.

Summary Gender is an important factor in the vulnerability to develop psychopathologies. At the biological level, stress-related pathologies such as depression or post-traumatic stress disorder (PTSD) are associated with profound disturbances of the hypothalamo-pituitary-adrenal (HPA) axis. The aim of the present study was to assess sex-differences in the long-term effect of an intense stressful procedure on HPA function and behaviour in the aversive context in rats. Female and male rats experienced an aversive procedure consisting in an electric footshock (2 mA, 10 s) in a dark chamber followed by 3 weekly situational reminders (SR, 2 min in the white chamber close to the footshock chamber). Our results indicate that 41 days after the end of the aversive procedure, female rats showed an increase of the corticosterone negative feedback in response to restraint stress, whereas such effect was not observed in males. Despite this change in the hormonal response, glucocorticoid receptors mRNA expression in the hippocampus was not affected in shocked females. In contrast, a significant increase of the mineralocorticoid receptors mRNA was observed in the CA2 of the hippocampus in shocked males. Finally, CRH mRNA levels in the paraventricular nucleus of the hypothalamus (PVN) were decreased in both female and male animals exposed to the aversive procedure. Behavioural observation revealed that shocked males and shocked females showed a high level of avoidance. However, the latency to visit the shock box was lower in females, which spent also more time in this area than males. In conclusion, our results suggest that gender might be a key factor impacting the direction of the effects induced by an intense stress. Interestingly, only females exhibited an increased negative feedback of the HPA axis response to stress, which could parallel endocrine changes of PTSD.

The effects of a 3-day water deprivation were studied in adult female rats in order to know what are the different zones of the adrenal gland and the hormonal factors involved in the growth and the activity of the adrenal gland. Water deprivation significantly increased plasma renin activity (PRA), plasma Angiotensin II (AII), vasopressin (AVP), epinephrine, aldosterone and corticosterone concentrations but did not modify the plasma adrenocorticotropin hormone (ACTH) level. Water deprivation significantly increased the absolute weight of the adrenal capsule containing the zona glomerulosa without modification of the density of cells per area unit suggesting that the growth of the adrenal capsule was due to a cell hyperplasia of the zona glomerulosa. Water deprivation significantly increased the density of AII type 1 (AT 1 ) receptors in the adrenal capsule but did not modify the density of AII type 2 (AT 2 ) receptors in the adrenal capsule and core containing the zona fasciculata, the zona reticularis and the medulla. The treatment of dehydrated female rats with captopril, which inhibits the angiotensin converting enzyme (ACE) in order to block the production of AII, significantly decreased the absolute weight of the adrenal capsule, plasma aldosterone and the density of AT 1 receptors in the adrenal capsule. The concentration of corticosterone in the plasma, the density of AT 2 receptors and the density of cells per unit area in the zona glomerulosa of the adrenal capsule were not affected by captopril-treatment. In conclusion, these results suggest that AII seems to be the main factor involved in the stimulation of the growth and the secretion of aldosterone by the adrenal capsule containing the zona glomerulosa during water deprivation. The low level of plasma ACTH is not involved in the growth of the adrenal gland but is probably responsible for the secretion of corticosterone by the zona fasciculata.

We investigated the effects of perinatal maternal malnutrition on the hypothalamo-pituitary-adrenal (HPA) axis activity in both basal and stressful conditions in newborn rats at weaning. Mothers from the control group were fed ad libitum. Mothers exposed to food restriction received 50% (FR50) of the daily intake of pregnant dams during the last week of gestation (Pre group), lactation (Post group) or both periods (PP group) in order to compare the long-term effects of gestational and/or lactational restriction. FR50 reduced the body growth of pups from the Post and PP groups as soon as day 11 until day 21 after birth. At weaning, pups of the Post and PP groups showed reduced adrenal, thymus and liver weights. Although the plasma adrenocorticotropic hormone (ACTH) level was reduced in pups, FR50 affected neither corticotropin-releasing hormone expression and peptide synthesis in the hypothalamus nor proopiomelanocortin expression in the adenohypophysis. Basal circulating levels of corticosterone were not markedly affected by FR50, but free corticosterone concentration was increased in the PP group. Plasma corticosterone-binding globulin (CBG) was decreased in newborns from both the Post and PP groups. Mineralocorticoid receptor gene expression was significantly increased in both CA1 and CA3 hippocampal areas in the PP group. Glucocorticoid receptor gene expression was increased in CA1, CA2 and dentate gyrus hippocampal areas in the Pre group, as well as in CA1, CA3 and DG areas in the Post group. The ether inhalation-induced plasma ACTH increase was weaker in pups from the Post and PP groups. Similarly, the ether inhalation-induced plasma corticosterone increase returned to basal levels in the Post group, or to weaker values than baseline in the PP group 90 min after this stressful procedure. The present work suggests that maternal food restriction during the perinatal period (gestation and lactation) or during lactation only reduces the postnatal somatic growth of pups and disturbs the activity of the HPA axis at weaning under both resting and stress conditions. A reduction in the plasma CBG-binding capacity, associated with a probable increase in hippocampal corticosteroid receptors, could reinforce glucocorticoid-mediated negative feedback and shorten stress-induced activation of the HPA axis in pups at weaning.

Rationnel L’environnement nutritionnel et metabolique au cours des phases precoces du developpement constitue un element cle dans le determinisme de l’obesite et du diabete et entraine des modifications epigenetiques susceptibles d’expliquer la transmission d’une generation a l’autre des pathologies metaboliques Objectif : Evaluer l’impact de la programmation nutritionnelle et d’un regime hyperlipidique sur la croissance et le metabolisme de la descendance. Materiels et methodes Des rats femelles issus de meres (F0) denutries (FR) ou de meres controles (C) nourries ad libitum sont soumises pendant 2 mois a un regime standard (S) ou un regime hyperlipidique (HF). Les femelles de la F1 sont reparties en 6 groupes experimentaux, 3 groupes C et 3 groupes FR recevant pendant la gestation un regime S (CS-S, CHF-S, FRS-S, FRHF-S) ou un regime HF (CHF-HF, FRHF-HF). Resultats Les femelles gestantes CHF-HF, FRS-S, FRHF-S et FRHF-HF presentent une intolerance partielle au glucose en l’absence d’obesite. Nous observons une macrosomie chez pres de 30 % de nouveau-nes des meres FRHF-S associee a une baisse des triglycerides plasmatiques maternels. A l’inverse, nous observons un retard de croissance intra-uterin (RCIU) chez pres de 22 % des nouveau-nes issus de meres CHF-HF et FRHF-HF en rapport avec une augmentation des NEFA plasmatiques maternels. L’analyse moleculaire des genes placentaires montre que la macrosomie est associee a une modification de l’expression des genes impliques dans le metabolisme lipidique, tandis que le RCIU implique l’expression de genes du stress oxydatif. Discussion La denutrition maternelle programme chez les femelles des anomalies de la tolerance au glucose responsables des alterations de la croissance fœtale dans la descendance. La manipulation du regime lipidique des meres conduit a des phenotypes opposes (macrosomie vs RCIU) en relation avec une expression genique placentaire differentielle. Conclusion Il reste a determiner si les nouveau-nes macrosomes et RCIU developpent a l’âge adulte des pathologies similaires.