Pulmonary exposure to particles during pregnancy causes increased neonatal asthma susceptibility

Maternal immune responses can promote allergy development in offspring, as shown in a model of increased susceptibility to asthma in babies of ovalbumin (OVA)-sensitized and -challenged mother mice. We investigated whether inflammatory responses to air pollution particles (diesel exhaust particles, DEP) or control "inert" titanium dioxide (TiO(2)) particles are enhanced during pregnancy and whether exposure to particles can cause increased neonatal susceptibility to asthma. Pregnant BALB/c mice (or nonpregnant controls) received particle suspensions intranasally at Day 14 of pregnancy. Lung inflammatory responses were evaluated 48 hours after exposure. Offspring of particle- or buffer-treated mothers were sensitized and aerosolized with OVA, followed by assays of airway hyperresponsiveness (AHR) and allergic inflammation (AI). Nonpregnant females had the expected minimal response to "inert" TiO(2). In contrast, pregnant mice showed robust and persistent acute inflammation after both TiO(2) and DEP. Genomic profiling identified genes differentially expressed in pregnant lungs exposed to TiO(2). Neonates of mothers exposed to TiO(2) (and DEP, but not PBS) developed AHR and AI, indicating that pregnancy exposure to both "inert" TiO(2) and DEP caused increased asthma susceptibility in offspring. We conclude that (1) pregnancy enhances lung inflammatory responses to otherwise relatively innocuous inert particles; and (2) exposures of nonallergic pregnant females to inert or toxic environmental air particles can cause increased allergic susceptibility in offspring.

Chorionic gonadotropin can enhance innate immunity by stimulating macrophage function

Human chorionic gonadotropin (hCG) is a placental glycoprotein, mainly secreted by trophoblasts during pregnancy. Its function in endocrine regulation has been well documented, but its immunological role is still largely unclear. For a successful pregnancy, an effective innate immunity is needed to protect the mother and fetus against infection, while maintaining tolerance against the paternal antigens of the fetus. The aim of this study was to investigate the effect of hCG on the function of macrophages (Mvarphi), which are major players in the innate response. hCG treatment of IFN-gamma-primed Mvarphi resulted in increased production of NO, reactive oxygen species, IL-6 and IL-12p40, and enhanced phagocytosis of apoptotic cells. hCG treatment did not affect the induction of allogeneic T cell proliferation by IFN-gamma-primed Mvarphi. The observed effects were receptor-mediated and involved the protein kinase A signaling pathway, as indicated by blocking studies using specific inhibitors. In vivo thioglycollate-elicited Mvarphi also exhibited increased phagocytic ability upon IFN-gamma activation and hCG treatment. In conclusion, hCG enhances Mvarphi functions involved in innate immunity, while the capacity to stimulate allogeneic T cells remains unchanged.

Cholesterol Transport by the Placenta: Placental Liver X Receptor Activity as a Modulator of Fetal Cholesterol Metabolism?

Cholesterol is an important sterol in mammals. Defects in cholesterol synthesis or intracellular routing have devastating consequences already in utero: the Smith-Lemli-Opitz syndrome, desmosterolosis and Niemann-Pick C1 disease provide examples of severe human inherited diseases caused by mutations in cholesterol metabolism genes. On the other hand, elevated plasma cholesterol concentrations are associated with the development of atherosclerosis which represents a major health risk in Western societies. Moreover, several studies indicate that development of atherosclerosis may already start during fetal life. Hence, a carefully balanced regulation of cholesterol metabolism appears of critical importance for both the development of the fetus and health of the adult. In the adult, the liver X receptor is a key regulator of cholesterol metabolism. Its target genes regulate cellular cholesterol efflux and thereby modulate whole-body cholesterol fluxes. LXR and several of its target genes have recently been demonstrated to be expressed in the placenta, which would provide a means to control delivery of maternal cholesterol to the fetus. Here we discuss the potential role of the placenta in the regulation of fetal cholesterol homeostasis and strategies to influence maternal-fetal cholesterol transfer.

Mechanisms of Disease: glucocorticoids, their placental metabolism and fetal 'programming' of adult pathophysiology

Epidemiological evidence suggests that an adverse prenatal environment permanently 'programs' physiology and increases the risk of cardiovascular, metabolic, neuroendocrine and psychiatric disorders in adulthood. Prenatal stress or exposure to excess glucocorticoids might provide the link between fetal maturation and adult pathophysiology. In a variety of animal models, prenatal stress, glucocorticoid exposure and inhibition (or knockout of) 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2)--the fetoplacental barrier to maternal glucocorticoids--reduce birth weight and cause increases in adult blood pressure, glucose levels, hypothalamic-pituitary-adrenal (HPA) axis activity and anxiety-related behaviors. In humans, mutations in the gene that encodes 11beta- hydroxysteroid dehydrogenase type 2 are associated with low birth weight. Babies with low birth weight have higher plasma cortisol levels throughout life, which indicates HPA-axis programming. In human pregnancy, severe maternal stress affects the offspring's HPA axis and is associated with neuropsychiatric disorders; moreover, maternal glucocorticoid therapy alters offspring brain function. The molecular mechanisms that underlie prenatal programming might reflect permanent changes in the expression of specific transcription factors, including the glucocorticoid receptor; tissue specific effects reflect modification of one or more of the multiple alternative first exons or promoters of the glucocorticoid receptor gene. Intriguingly, some of these effects seem to be inherited by subsequent generations that are unexposed to exogenous glucocorticoids at any point in their lifespan from fertilization, which implies that these epigenetic effects persist.

Pharmacokinetics of Levetiracetam during Pregnancy, Delivery, in the Neonatal Period, and Lactation

PURPOSE

To study pharmacokinetics of levetiracetam (LEV) during pregnancy, delivery, lactation, and in the neonatal period.

METHODS

Fourteen women with epilepsy receiving LEV treatment during pregnancy and lactation contributed with 15 pregnancies to this prospective study in which LEV concentrations in plasma and breast milk were determined. Trough maternal plasma samples were collected each trimester, and at baseline after delivery. Blood samples were obtained at delivery from mothers, from the umbilical cord, and from newborns during 2 days after delivery. LEV concentration was also determined in breast milk and in plasma collected from 11 of the mothers and their suckling infants after birth.

RESULTS

The umbilical cord/maternal plasma concentration ratios ranged from 0.56-2.0 (mean 1.15, n=13). LEV plasma concentrations in the neonates declined with an estimated half-life of 18 h (n=13). The mean milk/maternal plasma concentration ratio was 1.05 (range, 0.78-1.55, n=11). The infant dose of LEV was estimated to 2.4 mg/kg/day, equivalent to 7.9% of the weight-normalized maternal dose. Plasma concentrations in breastfed were approximately 13% of the mother's plasma levels. Maternal plasma concentrations during third trimester were only 40% of baseline concentrations outside pregnancy (p<0.001, n=7)

CONCLUSIONS

Our observations suggest considerable transplacental transport of LEV and fairly slow elimination in the neonate. Plasma concentrations of LEV in nursed infants are low despite an extensive transfer of LEV into breast milk. Pregnancy appears to enhance the elimination of LEV resulting in marked decline in plasma concentration, which suggests that therapeutic monitoring may be of value.

Multidrug resistance proteins affect drug transmission across the placenta

OBJECTIVE

We studied the role of multidrug resistance proteins in regulating transplacental transmission of corticosteroids and protease inhibitors.

STUDY DESIGN

We performed quantitative polymerase chain reaction and FACS analyses to study MDR1 (encodes P-glycoprotein) and MRP-1 expression in extravillous (HTR-8/SVneo) and villous (BeWo) trophoblast cells treated with saquinavir, a multidrug resistance protein substrate. We measured H3-dexamethasone and H3-ritonavir transfer across confluent, syncytialized BeWo cells before and after treatment with agents that inhibit multidrug resistance proteins.

RESULTS

Compared with baseline expression, messenger RNA and protein levels were increased significantly in trophoblast cells after treatment with saquinavir. H3-dexamethasone and H3-ritonavir levels increased in BeWo cells after treatment with anti-P-glycoprotein antibodies or cyclosporine A. Transfer of H3-labeled drugs from the apical (eg, maternal) to basolateral (eg, fetal) side of the syncytialized BeWo cell monolayer was increased significantly when cells were pretreated with anti-P-glycoprotein antibodies.

CONCLUSION

Multidrug resistance proteins regulate drug levels in trophoblast cells and may mediate transmission of therapeutic agents across the placenta.

Critical review: nicotine for the fetus, the infant and the adolescent?

The recent expansion of Nicotine Replacement Therapy to pregnant women and children ignores the fact that nicotine impairs, disrupts, duplicates and/or interacts with essential physiological functions and is involved in tobacco-related carcinogenesis. The main concerns in the present context are its fetotoxicity and neuroteratogenicity that can cause cognitive, affective and behavioral disorders in children born to mothers exposed to nicotine during pregnancy, and the detrimental effects of nicotine on the growing organism. Hence, the use of nicotine, whose efficacy in treating nicotine addiction is controversial even in adults, must be strictly avoided in pregnancy, breastfeeding, childhood and adolescence.

Effects of light ethanol consumption during pregnancy: increased frequency of minor anomalies in the newborn and altered contractility of umbilical cord artery

This study explores the effects of light maternal ethanol consumption during pregnancy on the appearance of minor malformations in neonates as well as on the contractile properties of their umbilical cord arteries (UCAs). Clinical external findings of newborns of women declaring light ethanol consumption during any period of their pregnancies [ethanol-exposed group (E group), n=79] were compared with those of nonexposed mothers [nonexposed to ethanol group (NE group), n=100]. Women who smoked or had any associated pathology were excluded. E group mothers consumed, on average, 200-250 mL ethanol/trimester (upper limit 700 mL/trimester). Sixty-six percent of the neonates in the E group presented at least one minor malformation (retromicrognathia and minor anomalies of the auricular/preauricular area were the more common), whereas only 16% of the NE group did (p=0.0000). The percentage of children exhibiting Apgar scores <7 was significantly greater in the E group (11% versus 2%, p=0.0119). UCAs from the E group developed significantly less contractile force (p<0.05) than those of the NE group when exposed to 1 microM serotonin (5-HT) or to a high K+ depolarizing solution. This difference persisted after inhibition of endothelial release of nitric oxide (NO) and prostacyclin. In conclusion, even light drinking should be considered a risk during pregnancy.

Early treatment of the pregnant guinea pig with IGFs promotes placental transport and nutrient partitioning near term

Appropriate partitioning of nutrients between the mother and conceptus is a major determinant of pregnancy success, with placental transfer playing a key role. Insulin-like growth factors (IGFs) increase in the maternal circulation during early pregnancy and are predictive of fetal and placental growth. We have previously shown in the guinea pig that increasing maternal IGF abundance in early to midpregnancy enhances fetal growth and viability near term. We now show that this treatment promotes placental transport to the fetus, fetal substrate utilization, and nutrient partitioning near term. Pregnant guinea pigs were infused with IGF-I, IGF-II (both 1 mg.kg-1.day-1) or vehicle subcutaneously from days 20-38 of pregnancy (term=69 days). Tissue uptake and placental transfer of the nonmetabolizable radio analogs [3H]methyl-D-glucose (MG) and [14C]aminoisobutyric acid (AIB) in vivo was measured on day 62. Early pregnancy exposure to elevated maternal IGF-I increased placental MG uptake by>70% (P=0.004), whereas each IGF increased fetal plasma MG concentrations by 40-50% (P<0.012). Both IGFs increased fetal tissue MG uptake (P<0.048), whereas IGF-I also increased AIB uptake by visceral organs (P=0.046). In the mother, earlier exposure to either IGF increased AIB uptake by visceral organs (P<0.014), whereas IGF-I also enhanced uptake of AIB by muscle (P=0.044) and MG uptake by visceral organs (P=0.016) and muscle (P=0.046). In conclusion, exogenous maternal IGFs in early pregnancy sustainedly increase maternal substrate utilization, placental transport of MG to the fetus, and fetal utilization of substrates near term. This was consistent with the previously observed increase in fetal growth and survival following IGF treatment.

The effects of maternal betamethasone administration on the intrauterine growth-restricted fetus

Intrauterine growth restriction (IUGR) is associated with altered fetal cardiovascular function to ensure adequate perfusion of essential organs. IUGR fetuses are at risk of preterm delivery and so are likely to receive antenatal glucocorticoids to promote lung maturation. Because glucocorticoids alter vascular tone, we questioned whether such treatment may induce fetal cardiovascular alterations. Using pregnant sheep carrying twins, we induced IUGR at approximately 0.7 gestation by single umbilical artery ligation in one twin, using the other twin as a control. In each fetus, we monitored carotid blood flow and arterial blood gases. We administered 11.4 mg betamethasone (n = 5) or vehicle (n = 4) to the ewe on d 5 (BM1) and 6 (BM2) postsurgery. On d 7, fetal brains were collected for immunohistochemistry. In control fetuses, carotid blood flow decreased 3.5 h post-BM1 by 24% (P < 0.001), returning to baseline at 5.5 h. In IUGR fetuses, carotid flow decreased 2.5 h post-BM1 by 27% and then increased by 25% over baseline, peaking at 11 h (P < 0.001). Compared to control + saline, we observed a significant increase in oxidative damage (4-hydroxynonenal-positive cells) in the fetal hippocampus and subcallosal area of all treatment groups (IUGR + BM > IUGR + saline = control + BM). There was a significant correlation between carotid blood flow reperfusion after betamethasone and the number of 4-hydroxynonenal-positive cells in the cortex and hippocampus. These data suggest that antenatal betamethasone may induce brain injury in the IUGR fetus but not in the normally grown fetus.

Acute ethanol exposure in pregnancy alters the insulin-like growth factor axis of fetal and maternal sheep

Maternal ethanol intake during pregnancy impairs fetal growth, but mechanisms are not clearly defined. Reduced IGF abundance or bioavailability in the fetus and/or mother may contribute to this growth restriction. We hypothesized that an episode of acute ethanol exposure, mimicking binge drinking would restrict fetal growth and perturb the maternal and fetal IGF axes. Pregnant sheep were infused intravenously with saline or ethanol (1 g/kg maternal wt) over 1 h, on days 116, 117, and 118 of gestation (start of 1st infusion = time 0, term is 147 days). Maternal and fetal plasma IGF and IGF-binding protein (IGFBP) concentrations were measured before and after each infusion. Compared with controls, ethanol exposure reduced fetal weight at day 120 by 19%, transiently reduced maternal plasma IGF-I (-35%) at 30 h, and decreased fetal plasma IGF-II (-28%) from 24 to 54 h after the first infusion. Ethanol exposure did not alter maternal or fetal plasma concentrations of IGFBP-2 and IGFBP-3, measured by Western ligand blotting. We conclude that suppression of maternal and fetal IGF abundance may contribute to fetal growth restriction induced by acute or binge ethanol exposure.

A Description of the Preterm Fetal Sheep Systemic and Central Responses to Maternal General Anesthesia

BACKGROUND

The second trimester is recommended as the optimal time to conduct a surgical procedure on pregnant patients, even though the fetal responses to anesthesia at this age are not known. Here we assessed the responses of preterm fetal sheep to a standard anesthetic regimen of midazolam, thiopental, and isoflurane.

METHODS

Variables were monitored in previously instrumented preterm pregnant sheep before, during, and after 4 h of general anesthesia. Isoflurane produced moderate fetal hypotension and bradycardia, whereas extubation was accompanied by increases in fetal heart rate and mean arterial blood pressure.

RESULTS

We observed an initial increase in fetal Sao2 followed by a gradual decline to baseline. Within the fetal brain, oxygenated hemoglobin changed by <10% (nonsignificant) and deoxygenated hemoglobin and total hemoglobin varied by <5%. Overall, although O2 levels within the preterm fetal brain were not independently enhanced by isoflurane (as occurs in the older fetus and in the adult), they did remain constant even as fetal mean arterial pressure decreased by more than 20%. By extension, we failed to identify changes in cerebral oxygenation that could be construed as injurious.

CONCLUSION

Any adverse preterm fetal response to maternal surgery should not be attributed solely to the actions of general anesthesia upon the fetus.

Critical period and minimum single oral dose of ochratoxin A for inducing developmental toxicity in pregnant Wistar rats

Ochratoxin A (OTA), a potent in vivo teratogen, has been tested in various laboratory animal species. Present investigation was conducted to determine critical dose and critical time for the developmental toxicity of OTA in pregnant Wistar rats after single oral dose administration. OTA at different graded dose levels (2-4 mg/kg body weight) and at different gestation days (6-15), caused variable developmental defects in developing fetuses. OTA at 2.75 mg/kg body weight, dissolved in 0.1 M sodium bicarbonate (vehicle) and administered by oral intubation as a single dose on one of the gestational days 6-15, caused significant maternal toxicity in the dams and various gross, visceral and skeletal anomalies in the fetuses. The major gross malformations were external hydrocephaly, incomplete closure of skull and omphalocele. Internal hydrocephaly, microphthalmia, enlarged renal pelvis and renal hypoplasia were the main internal soft tissue anomalies. Major skeletal defects were developmental defects in skull bones, sternebrae, vertebrae and ribs. The gestational days 6 and 7 were found to be the most critical for the induction of teratogenicity in rats. Single oral dose of 2.75 mg/kg body weight OTA was found to be the minimum effective teratogenic dose in pregnant Wistar rats.

Kinetics of betamethasone and fetal cardiovascular adverse effects in pregnant sheep after different doses

OBJECTIVE

To study the pharmacokinetics of different betamethasone doses and preparations used to enhance fetal lung maturation in the maternal and fetal circulation of sheep and the adverse effects on fetal blood pressure.

METHODS

Doses of 170 (n = 6) and 110 microg/kg (n = 6) betamethasone phosphate equivalent to 12 or 8 mg, respectively, administered to a 70 kg pregnant woman or 170 microg/kg (n = 6) of a depot formulation (50% betamethasone phosphate and 50% betamethasone acetate) were injected intramuscularly to chronically instrumented pregnant sheep.

RESULTS

Both betamethasone preparations produced highest maternal concentrations after 15 min followed by an exponential decline with a t(1/2) of about 3 hours. The drug fell below the limit of detection at 8 to 12 hours. Betamethasone was first detectable in the fetal circulation at 1 hour, peaked at 3 hours, and decreased below the limit of detection at 8 hours independently of the dose or preparation. Maternal and fetal betamethasone concentrations achieved with the phosphate and acetate formulation were one half of those obtained with betamethasone phosphate, suggesting that very little betamethasone is released from the acetate within the first 8 hours when the effect on lung maturation is needed. Betamethasone led to a maximal increase of mean fetal blood pressure from 42+/-1 to 51+/-1 mm Hg (P < .05) and did not differ between the doses and preparations, although plasma concentrations showed a clear dose-concentration relationship.

CONCLUSION

The doses of betamethasone used in obstetrics are supramaximal in terms of cardiovascular effects in sheep. Risk-benefit studies are needed to find the effective steroid dose with the least adverse effects.

Phthalate monoesters in perfusate from a dual placenta perfusion system, the placenta tissue and umbilical cord blood

Fetal exposure to phthalates may be associated with adverse reproductive effects, including cryptorchidism and decreased semen quality. Information about human placental transfer is needed to qualify the hypotheses. A dual recirculating placenta perfusion system to monitor concentrations of eight phthalate monoesters in fetal and maternal perfusates was established. In addition to perfusate background measures of phthalate monoesters, the concentrations in umbilical cord plasma and placenta tissue were measured. Monomethyl phthalate (mMP), monoethyl phthalate (mEP), monobutyl phthalate (mBP), and mono (2-ethyl-hexyl) phthalate (mEHP) were detected in both maternal and fetal perfusate, demonstrating a release of compounds from tissue or blood to perfusates. The distribution of compounds between perfusate, umbilical cord plasma, and tissue was in accordance with the physical-chemical properties of the compounds. Results from the present study of compounds residing in the tissue are essential before studying human transplacental transfer, storage, and metabolism of selected phthalate monoesters.

Effect of in utero exposure to di-(2-ethylhexyl)phthalate: distribution in the rat fetus and testosterone production by rat fetal testis in culture

DEHP is known to cause reproductive toxicity in rats, particularly during the neonatal period. Pregnant and brood rats were treated by gavage with 750 mg/kgb.w./day DEHP starting on GD14 within PND4. Two hours after (14)C-DEHP administration on GD15, GD18, GD21 and PND4, the radioactivity content was measured in the dams blood and in the liver, gonads and carcass of the offspring. The radioactivity concentration recovered in the fetuses was one or two order of magnitude lower than the concentration found in the dam plasma. A low proportion of radioactivity was present in fetal gonads, ca. 2%, 5% and 3.6% on GD18, GD21 and PND4, respectively. The effect on testosterone production of DEHP and its metabolites (MEHP, metabolites VI and IX) was assessed in fetal testis cultures using a dose-range which included the maximal exposure observed in vivo. None of the compounds affected testosterone production. Thus, DEHP and/or its metabolites appear to cross the placental barrier, reach the fetal gonads. In vitro, neither DEHP nor its main metabolites decreased the testosterone production.

Influence of a single course of antenatal betamethasone on the maternal-fetal insulin-IGF-GH axis in singleton pregnancies

OBJECTIVE

We examined the hypothesis that a single course of antenatal betamethasone influences the maternal-fetal insulin-IGF-GH axis.

DESIGN

A prospective, observational, pilot study consisting of four groups of pregnant women: (I) received betamethasone and delivered <2 weeks post treatment; (II) received betamethasone and delivered >2 weeks post treatment; (III) untreated women who delivered <37 weeks (preterm controls); (IV) untreated women who delivered >37 weeks (term controls). Maternal and mixed umbilical cord blood was collected at delivery and analyzed for insulin, glucose, IGF-I, IGF-II, IGFBP-1, IGFBP-3, GH, and GHBP.

RESULTS

Betamethasone increased maternal insulin, glucose and IGF-I levels without affecting IGFBPs. In the fetal compartment, betamethasone treatment was associated with a delayed suppressive effect on GH and a sustained suppressive effect on IGF-II levels. There were no differences in infant size or neonatal morbidities between patients who delivered <2 weeks or >2 weeks post betamethasone treatment. In Group IV, birth weight correlated positively with cord IGF-I levels (r2=0.41, p=0.0098) and negatively with cord IGFBP-1 levels (r2=0.51, p=0.0039), and ponderal index correlated negatively with cord IGFBP-1 levels (r2=0.27, p<0.05).

CONCLUSIONS

A single course of antenatal betamethasone influences the maternal-fetal insulin-IGF-GH axis, particularly fetal IGF-II levels, without measurable anthropometric changes at birth. Whether these effects have implications beyond the neonatal period remains to be determined.

A reproductive screening test of feverfew: is a full reproductive study warranted?

Feverfew is currently used in the treatment of migraine and arthritis. It is traditionally contraindicated in pregnancy but there are no studies confirming this warning. An in vivo and in vitro preliminary screen was performed using a rat model: five female rats were orally dosed with 839 mg/kg feverfew daily on either gestation days (GD) 1-8 or 8-15. On GD20, rats were sacrificed and fetuses, placentae and ovaries were collected. The fetuses were weighed and examined for malformations. While maternal weight gain appeared to be reduced, ANCOVA analysis suggested that the difference was due to litter size, rather than treatment. Pre-implantation loss appeared increased but this was not statistically significant in the feverfew GD1-8 group. Fetuses exposed to feverfew from GD8-15 were smaller than ethanol controls perhaps as a result of the increased frequency of runts in treated litters. Feverfew induced toxicity when GD10.5 embryos were cultured for 26 h in rat serum to which extract was added. The results of the present preliminary study suggest that a comprehensive reproductive study of feverfew is warranted.

Effects of lactational cyclosporine A use on rat pups

We aimed to evaluate the structural and functional changes in the thymus and kidneys of rat pups whose mothers were given cyclosporine A (CsA) during lactational period. Six adult nursing Wistar rats and their 30 pups were studied. Rat pups were divided into four groups as follows: 21-day treated group and 21-day placebo group, each including 10 breastfeeding pups sacrificed on the 21st day, whose mothers were given CsA or placebo, respectively (infancy groups) and, 60-day treated group and 60-day placebo group, each including five breastfeeding pups sacrificed on the 60th day, whose mothers were given CsA or placebo, respectively (puberty groups). While CsA levels of mother rats were very high, CsA levels of 21-day treated group pups were zero. There were no renal histomorphometric differences between study and control pups in both age groups. Renal function parameters showed significant differences between study and control pups in the infancy group: the 21-day treated group pups had significantly lower urine volume, proteinuria, FE(Na) and urinary NAG/creatinine ratio. GFR was also lower in the 21-day treated group, but the difference was not significant, and serum creatinine levels were also not different. Renal function differences were not present among the pubertal pups. Thymic corticomedullary ratio of the 21-day treated group was significantly higher than the 21-day placebo group, while there was no difference between the 60-day treated group and 60-day placebo group. There were no significant changes in the number and distribution of CD3+, CD4+, and CD8+ thymocytes between study and control pups in both age groups. In conclusion, breastfeeding by CsA-treated mother rats induced structural alterations in the thymus and functional changes in the kidneys of the rat pups during infancy. Disturbances in the kidneys and thymus mostly improved after CsA exposure was over.

The effect of aromatase inhibition on the sexual differentiation of the sheep brain

This study tested the hypothesis that aromatization of testosterone to estradiol is necessary for sexual differentiation of the sheep brain. Pregnant ewes (n = 10) were treated with the aromatase inhibitor 1,4,6- androstatriene-3,17-dione (ATD) during the period of gestation when the sheep brain is maximally sensitive to the behavior-modifying effects of exogenous testosterone (embryonic d 50-80; 147 d is term). Control (n = 10) ewes received vehicle injections. Fifteen control lambs (7 males and 8 females) and 17 ATD-exposed lambs (7 males and 10 females) were evaluated for sexually dimorphic behavioral and neuroendocrine traits as adults. Prenatal ATD exposure had no significant effect on serum concentrations of androgen at birth, growth rates, expression of juvenile play behaviors, or the onset of puberty in male and female lambs. Rams exposed to ATD prenatally exhibited a modest, but significant, decrease in mounting behavior at 18 mo of age. However, prenatal ATD exposure did not interfere with defeminization of adult sexual partner preferences, receptive behavior, or the LH surge mechanism. In summary, our results indicate that aromatization is necessary for complete behavioral masculinization in sheep. However, before we can conclude that aromatization does not play a role in defeminization of the sheep brain, it will be necessary to evaluate whether intrauterine exposure of male fetuses to higher doses of ATD for a more extended period of time can disrupt normal neuroendocrine and behavioral development.

Chronic intake of caffeine during gestation down regulates metabotropic glutamate receptors in maternal and fetal rat heart

Caffeine is the most widely consumed substance in the world which antagonizes adenosine effects. Adenosine acting through A(1) receptors inhibits glutamate release which binds to metabotropic glutamate receptors (mGluRs). Recently, we have shown that maternal caffeine intake during gestation causes down-regulation of A(1) and metabotropic glutamate receptors in the brain of both rat mothers and fetuses. In the present work we provide evidence that caffeine also affects receptors in hearts, causing a decrease in mGluRs from both maternal and fetal hearts. A decrease in G(q/11) and PLC beta(1) proteins level was also observed in both tissues. However, phospholipase C activity was only affected in fetal heart, being significantly decreased. These results suggest an in vivo cross-talk mechanism between adenosine and glutamate receptors in peripheral tissues. Therefore, special attention should be paid to caffeine ingestion during gestation.

Lack of effect of metyrapone and exogenous cortisol on early porcine conceptus development

A study was conducted to evaluate the influence of maternal cortisol on early conceptus development in pigs (Sus scrofa). The corticosteroid synthesis inhibitor metyrapone was injected daily during days 14-19 of pregnancy, without (n = 6) and with commensurate administration of cortisol (n = 6). Blood samples were taken via an indwelling jugular catheter on days 14 and 18, and conceptuses were harvested during surgery on day 20. Compared with vehicle-injected control dams (n = 7) plasma cortisol and aldosterone concentrations were decreased (P < 0.01) by 52 and 29%, respectively, by metyrapone treatment. Cortisol administration reversed decreases in plasma cortisol by day 18. There were no treatment-associated effects on conceptus survival or size. Nor were there treatment-associated effects on allantoic fluid volume or content. Trophodermal glucocorticoid receptor (GR) mRNA expression decreased by 34% (P < 0.05) in metyrapone-treated pigs, and was not further influenced by concomitant administration of cortisol, thereby suggesting an influence of aldosterone on GR mRNA expression. Also, when all pigs were considered, there were treatment-independent second-order polynomial regressions (P < 0.05) between maternal plasma cortisol concentrations and embryonic weight, allantoic size and allantoic glucose concentrations, and between plasma aldosterone concentrations and trophodermal GR mRNA expression. Such biphasic corticosteroid concentration versus tissue parameter curves are noteworthy, but difficult to interpret validly. They may suggest that an appropriate corticosteroid environment is necessary for optimal porcine embryonic development during this stage of gestation, but cannot overshadow the absence of treatment effects on the porcine embryonic measures evaluated.

Consequences of paternal cocaine exposure in mice

The present study examined the potential neuroteratological effects of paternal cocaine (COC) exposure using the novel mouse model of inhalational drug administration. In this model, mice were trained to self-administer COC in multi-hour daily inhalation sessions reminiscent of crack binges. The controls included males pair-fed with COC-inhaling animals as well as ad-lib-fed males. All males were bred with drug-naive females. The newborn pups sired by COC-inhaling males had a reduced biparietal head diameter, suggesting a decreased cerebral volume. When the pups reached adulthood, their sustained visuo-spatial attention and spatial working memory were tested using a 5-arm maze paradigm. During the attention tests, the percentage of correct trials at the shortest stimulus duration employed in the study (0.5 s) was significantly lower for the male offspring of COC-inhaling fathers as compared to the offspring of both pair-fed and ad-lib-fed controls. For the females sired by COC-inhaling fathers, the deficit was observed at light stimulus durations of 0.5 and 0.75 s. Also, during the working memory tests, the male offspring of COC-inhaling fathers required more sessions than the offspring of either pair-fed or ad-lib-fed fathers to reach the selected criterion at retention intervals of 16 min and longer. The impairment of working memory in female offspring of COC-inhaling fathers was even stronger, as the offspring needed more sessions to reach the criterion as compared to their control counterparts, even at retention intervals as short as 4 min. These findings suggest that paternal COC abuse prior to coitus may impact the development of the offspring, particularly if they are females. We further showed that chronic COC exposure in male mice does not result in substantial breakage of spermatozoal DNA, but significantly alters expression of DNA methyltransferases 1 and 3a in the germ cell-rich seminiferous tubules of the testis. Since these enzymes are essential for generating and maintaining parental gene imprinting in germ cells, our observations point to an intriguing possibility that COC may cause paternally induced neuroteratological effects by interfering with gene-imprinting patterns in male gametes.

Use of systemic glucocorticosteroids in pregnancy: Be alert but not alarmed

SUMMARY Concerns have been raised regarding the use of repeated courses of systemic glucocorticosteroids given to pregnant women with threatened premature labour to improve fetal lung maturity. Most worrying are animal studies showing detrimental effects on the developing brain, though human data to date are conflicting. Additional concerns relate to the fetal origins of adult diseases, particularly vascular diseases such as hypertension and atherosclerosis. It is currently recommended that obstetricians give only a single course of antenatal corticosteroids to pregnant women to enhance lung maturity instead of giving repeated doses, which was previously a common practice. Other clinicians including dermatologists, gastroenterologists and rheumatologists may have reason to provide systemic glucocorticosteroids to pregnant women. Although systemic glucocorticosteroids all cross the placenta to some degree, the extent to which they do so depends on the drug involved. The choice of systemic glucocorticosteroid for the pregnant women in light of this evolving literature is discussed.