Maternal Alcohol Abuse and Neonatal Infection

Moderate Prenatal Alcohol Exposure Increases Toll-like Receptor Activity in Umbilical Cord Blood at Birth: A Pilot Study

The prevalence of prenatal alcohol exposure (PAE) is increasing, with evidence suggesting that PAE is linked to an increased risk of infections. PAE is hypothesized to affect the innate immune system, which identifies pathogens through pattern recognition receptors, of which toll-like receptors (TLRs) are key components. We hypothesized that light-to-moderate PAE would impair immune responses, as measured by a heightened response in cytokine levels following TLR stimulation. Umbilical cord samples (10 controls and 8 PAE) from a subset of the Ethanol, Neurodevelopment, Infant and Child Health Study-2 cohort were included. Peripheral blood mononuclear cells (PMBCs) were stimulated with one agonist (TLR2, TLR3, TLR4, or TLR9). TLR2 agonist stimulation significantly increased pro-inflammatory interleukin-1-beta in the PAE group after 24 h. Pro- and anti-inflammatory cytokines were increased following stimulation with the TLR2 agonists. Stimulation with TLR3 or TLR9 agonists displayed minimal impact overall, but there were significant increases in the percent change of the control compared to PAE after 24 h. The results of this pilot investigation support further work into the impact on TLR2 and TLR4 response following PAE to delineate if alterations in levels of pro- and anti-inflammatory cytokines have clinical significance that could be used in patient management and/or attention to follow-up.

In Utero Exposure to Antibiotics and Risk of Serious Infections in the First Year of Life

INTRODUCTION AND OBJECTIVE

Given the high prevalence of antibiotic prescription during pregnancy in France and previous studies suggesting an increased risk of infection in offspring with such exposures, our study aimed to investigate the association between prenatal exposure to systemic antibiotics and serious infections in full-term infants during their first year of life.

METHODS

We conducted a retrospective population-based cohort study on singleton, full-term liveborn non-immunocompromised infants, using the French National Health Data System (SNDS) between 2012 and 2021. Systemic antibiotic dispensing in ambulatory care settings during pregnancy defined the exposure. Outcomes concerned serious infections (i.e., infections requiring hospitalization) in offspring identified between 3 and 12 months of life, hence excluding infections of maternal origin. Adjusted odds ratios (aORs) were estimated using logistic regression with multivariate models to control for potential confounders.

RESULTS

Of 2,836,630 infants included, 39.6% were prenatally exposed to systemic antibiotics. Infants prenatally exposed to antibiotics had a higher incidence of serious infections compared with unexposed infants {aOR 1.12 [95% confidence interval (95% CI) 1.11-1.13]}. Similar associations were observed according to the timing of exposure during pregnancy, antibiotic class, and site of infections. The strongest association was observed when infants were prenatally exposed to three or more antibiotic courses during pregnancy [aOR 1.21 (95% CI 1.19-1.24)]. Limitations include residual confounders, such as genetic susceptibility to infections and the role of the underlying pathogen agent.

CONCLUSION

Prenatal exposure to systemic antibiotics is very common and is associated with a weak yet significant associations with subsequent serious infectious events during the first year of life. While our study revealed associations, it is important to note that causation cannot be established, given the acknowledged limitations, including potential confounding by indication.

Developmental alcohol exposure is exhausting: Sleep and the enduring consequences of alcohol exposure during development

Prenatal alcohol exposure is the leading nongenetic cause of human intellectual impairment. The long-term impacts of prenatal alcohol exposure on health and well-being are diverse, including neuropathology leading to behavioral, cognitive, and emotional impairments. Additionally negative effects also occur on the physiological level, such as the endocrine, cardiovascular, and immune systems. Among these diverse impacts is sleep disruption. In this review, we describe how prenatal alcohol exposure affects sleep, and potential mechanisms of those effects. Furthermore, we outline the evidence that sleep disruption across the lifespan may be a mediator of some cognitive and behavioral impacts of developmental alcohol exposure, and thus may represent a promising target for treatment.

Effects of prenatal alcohol exposure on infant lung function, wheeze, and respiratory infections in Australian children

BACKGROUND

Prenatal alcohol exposure (PAE) is a known risk factor for a range of adverse outcomes, such as facial dysmorphism, adverse birth outcomes, and neurodevelopmental changes. Preclinical research shows that PAE also inhibits lung development, lowers surfactant protein expression, has detrimental effects on alveolar macrophages, and decreases both T and B cell numbers. However, clinical evidence of respiratory impacts from PAE is limited. This study explored whether lung function, wheeze, and incidence of respiratory infections differ in children with PAE compared with unexposed children.

METHODS

Data from the Barwon Infant Study (n = 1074) were examined. PAE data were extracted from maternal questionnaires at trimesters 1 and 2 (combined), and trimester 3, and included as "total standard drinks" during each trimester and total pregnancy intake, a binary yes/no for PAE, and binge drinking (>5 standard drinks in one session). Respiratory outcomes were parent-reported wheeze, lung function (measured by multiple breath washout), and parent report and medical record indicators of health service attendances for respiratory conditions. Linear and logistic regressions were performed to quantify relationships between PAE and respiratory outcomes, controlling for socioeconomic status, birthweight, sex, gestational age, and maternal smoking.

RESULTS

Binge drinking was associated with increased health service attendance for respiratory condition(s) in the first 12 months of life (OR = 5.0, 95% CI (1.7, 20.7), p = 0.008). We did not find a relationship between binary PAE and binge drinking with lung function at 4 weeks of age or wheeze at 12 months. The number of standard drinks consumed in trimester two was associated with a lower lung clearance index (β = -0.011 turnovers, 95% CI (-0.0200, -0.0013), p = 0.03), and a small increase in functional residual capacity (β = 0.34 mL, 95% CI (0.02, 0.66), p = 0.04).

CONCLUSIONS

We found an association between binge drinking and health service utilization for respiratory conditions in infancy, but no evidence that low-level PAE was associated with adverse respiratory outcomes.

Impact of the COVID-19 pandemic on adults with Fetal Alcohol Spectrum Disorder: linking immune function to mental health status

Prenatal alcohol exposure (PAE) is known to cause a variety of cognitive, behavioral, and neurological changes. Importantly, mental health problems are also overrepresented in individuals with Fetal Alcohol Spectrum Disorder (FASD), the group of neurodevelopmental conditions that can occur following PAE. Approximately 90% of individuals with FASD report experiencing mental health problems over their lifespan, compared to approximately 30% in the overall population. Individuals with FASD also display impairments in coping skills and increased vulnerability to stress. Here, we investigated whether the COVID-19 pandemic would have a differential impact on mental health and inflammation-to-mood associations in adults with FASD, compared to unexposed controls (no PAE). We capitalized on our pre-pandemic study examining health and immune function and invited past-participants to enroll in the current study. Participants completed mental health assessments and COVID-related questionnaires by phone. In addition, blood samples collected at baseline (pre-pandemic) were used to probe for inflammation-to-mood associations. Overall, our results indicate that lower SES was predictive of higher coronavirus anxiety scores, with no differences between adults with FASD and controls. In addition, while there were no differences in depression or anxiety measures at baseline (pre-pandemic) or during the pandemic, examination of inflammation-to-mood associations identified differential relationships in adults with FASD compared to unexposed controls. Specifically, there was a positive association between baseline neutrophil counts and both baseline and pandemic mental health scores in unexposed controls only. In addition, for unexposed controls there was also a negative association between baseline interferon-ɣ (IFN-ɣ) and pandemic mental health scores. By contrast, only adults with FASD showed positive associations between baseline interleukin-12p70 (IL-12p70), IL-8, soluble intercellular adhesion molecule-1 (sICAM-1), and soluble vascular cell adhesion molecule-1 (sVCAM-1) and pandemic mental health scores. Taken together, to our knowledge, this study is the first to examine the impact of the pandemic in adults with FASD. And while it may be too soon to predict the long-term effects of the pandemic on mental health, our data suggest that it will be important that future work also takes into account how immune function may be modulating mental health outcomes in this population.

Blood Vessels as a Key Mediator for Ethanol Toxicity: Implication for Neuronal Damage

Excessive intake of ethanol is associated with severe brain dysfunction, and the subsequent neurological and behavioral abnormalities are well-established social risks. Many research studies have addressed how ethanol induces neurological toxicity. However, the underlying mechanisms with which ethanol induces neurological toxicity are still obscure, perhaps due to the variety and complexity of these mechanisms. Epithelial cells are in direct contact with blood and can thus mediate ethanol neurotoxicity. Ethanol activates the endothelial cells of blood vessels, as well as lymphatic vessels, in a concentration-dependent manner. Among various signaling mediators, nitric oxide plays important roles in response to ethanol. Endothelial and inducible nitric oxide synthases (eNOS and iNOS) are upregulated and activated by ethanol and enhance neuroinflammation. On the other hand, angiogenesis and blood vessel remodeling are both affected by ethanol intake, altering blood supply and releasing angiocrine factors to regulate neuronal functions. Thus, ethanol directly acts on endothelial cells, yet the molecular target(s) on endothelial cells remain unknown. Previous studies on neurons and glial cells have validated the potential contribution of membrane lipids and some specific proteins as ethanol targets, which may also be the case in endothelial cells. Future studies, based on current knowledge, will allow for a greater understanding of the contribution and underlying mechanisms of endothelial cells in ethanol-induced neurological toxicity, protecting neurological health against ethanol toxicity.

Alcohol exposure prior to pregnancy-does hazardous consumption affect placenta- and inflammatory-mediated pregnancy outcomes? A Swedish population-based cohort study

INTRODUCTION

Alcohol consumption during pregnancy is related to severe birth complications such as low birthweight, preterm birth and birth defects. During the last decade, the Alcohol Use Disorders Identification Test (AUDIT) has been used as a screening tool in Swedish maternal healthcare units to identify hazardous, pre-pregnancy alcohol use. However, evaluation of the screening with AUDIT, as well as adverse maternal or neonatal outcomes, has not been assessed at a national level.

MATERIAL AND METHODS

This was a population-based cohort study of 530 458 births from 2013 to 2018 using demographic, reproductive and maternal health data from the Swedish Pregnancy Register. Self-reported alcohol consumption in the year before pregnancy, measured as AUDIT scores, was categorized into moderate (6-13 points) and high-risk (14-40 points) consumption, with low-risk (0-5 points) consumption as the reference group. Associations with pregnancy- and birth outcomes were explored with logistic regressions using generalized estimating equation models, adjusting for maternal and socioeconomic characteristics. Estimates are presented as adjusted odds ratios (aORs) with 95% confidence intervals (CIs).

RESULTS

High-risk and moderate pre-pregnancy alcohol consumption was associated with preeclampsia, preterm birth and birth of an infant small for gestational age (SGA), but these associations were nonsignificant after adjustments. Prior moderate-risk (aOR 1.29, 95% CI 1.17-1.42) and high-risk consumption (aOR 1.62, 95% CI 1.17-2.25) increased the likelihood of intrapartum and neonatal infections.

CONCLUSIONS

Apart from identifying hazardous alcohol consumption prior to pregnancy and the offer of counseling, screening with the AUDIT in early pregnancy indicates a high risk of inflammatory-/placenta-mediated pregnancy and birth outcomes. For most outcomes, AUDIT was not an independent contributor when adjusting for confounding factors. Hazardous alcohol use prior to pregnancy was independently linked to intrapartum and neonatal infections; conditions associated with morbidity and long-term sequalae. These associations may be explained by alcohol-induced changes in the maternal or fetal immune system in early pregnancy or persistent alcohol intake during pregnancy, or may depend on unidentified confounding factors.

The impact of opioid exposure during pregnancy on the human neonatal immune profile

BACKGROUND

The increasing magnitude of the opioid crisis and rising rates of neonatal abstinence syndrome (NAS) diagnoses highlight the need for increased research into how maternal substance use during pregnancy can impact the neonatal immune profile and its functionality. We hypothesized that neonates with opioid exposure would have reduced proportions of some immune cells, an anti-inflammatory cytokine profile, reduced T cell proliferation, and monocyte bacterial killing activity compared to the control population.

METHODS

The present study compares immune cell populations, inflammatory and anti-inflammatory cytokine and chemokine levels in the serum, and monocyte and T cell functional activity using umbilical cord samples from neonates with known opioid exposure during gestation and from control neonates without known exposure.

RESULTS

Our findings demonstrated a significant reduction in neutrophils, decreased levels of inflammatory cytokines in the serum, and reduced IL-2 production during in vitro CD4⁺ T cell proliferation in neonates exposed to opioids compared to controls. The neutrophil findings were supported by retrospective analysis of an extended network of deidentified patient records.

CONCLUSIONS

This study is the first of its kind to evaluate differences in neonatal immunity as a result of opioid exposure in the human population that will inform continued mechanistic studies.

IMPACT

The opioid epidemic has become a public health crisis in the United States, and the corresponding incidence of neonatal abstinence syndrome (NAS) have risen accordingly. New research is required to understand the short and long-term health impacts of opioid exposure to the neonate. This is the first human study to investigate the immunologic profile and functionality in neonates with known opioid exposure in utero. The abundance of neutrophils and the ratio of neutrophils to lymphocytes is significantly reduced along with inflammatory cytokines and chemokines following opioid exposure during pregnancy. The immune profile in opioid-exposed neonates may promote susceptibility to infection.

Intersection of Epigenetic and Immune Alterations: Implications for Fetal Alcohol Spectrum Disorder and Mental Health

Prenatal alcohol exposure can impact virtually all body systems, resulting in a host of structural, neurocognitive, and behavioral abnormalities. Among the adverse impacts associated with prenatal alcohol exposure are alterations in immune function, including an increased incidence of infections and alterations in immune/neuroimmune parameters that last throughout the life-course. Epigenetic patterns are also highly sensitive to prenatal alcohol exposure, with widespread alcohol-related alterations to epigenetic profiles, including changes in DNA methylation, histone modifications, and miRNA expression. Importantly, epigenetic programs are crucial for immune system development, impacting key processes such as immune cell fate, differentiation, and activation. In addition to their role in development, epigenetic mechanisms are emerging as attractive candidates for the biological embedding of environmental factors on immune function and as mediators between early-life exposures and long-term health. Here, following an overview of the impact of prenatal alcohol exposure on immune function and epigenetic patterns, we discuss the potential role for epigenetic mechanisms in reprogramming of immune function and the consequences for health and development. We highlight a range of both clinical and animal studies to provide insights into the array of immune genes impacted by alcohol-related epigenetic reprogramming. Finally, we discuss potential consequences of alcohol-related reprogramming of immune/neuroimmune functions and their effects on the increased susceptibility to mental health disorders. Overall, the collective findings from animal models and clinical studies highlight a compelling relationship between the immune system and epigenetic pathways. These findings have important implications for our understanding of the biological mechanisms underlying the long-term and multisystem effects of prenatal alcohol exposure, laying the groundwork for possible novel interventions and therapeutic strategies to treat individuals prenatally exposed to alcohol.

Cord Blood-Based Approach to Assess Candidate Vaccine Adjuvants Designed for Neonates and Infants

Neonates and infants are particularly susceptible to infections, for which outcomes tend to be severe. Vaccination is a key strategy for preventing infectious diseases, but the protective immunity achieved through vaccination typically is weaker in infants than in healthy adults. One possible explanation for the poor acquisition of vaccine-induced immunity in infants is that their innate immune response, represented by toll-like receptors, is immature. The current system for developing pediatric vaccines relies on the confirmation of their safety and effectiveness in studies involving the use of mature animals or adult humans. However, creating vaccines for neonates and infants requires an understanding of their uniquely immature innate immunity. Here we review current knowledge regarding the innate immune system of neonates and infants and challenges in developing vaccine adjuvants for those children through analyses of cord blood.

Neuroinflammation and Brain Development: Possible Risk Factors in COVID-19-Infected Children

COVID-19, a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) betacoronavirus, affects children in a different way than it does in adults, with milder symptoms. However, several cases of neurological symptoms with neuroinflammatory syndromes, such as the multisystem inflammatory syndrome (MIS-C), following mild cases, have been reported. As with other viral infections, such as rubella, influenza, and cytomegalovirus, SARS-CoV-2 induces a surge of proinflammatory cytokines that affect microglial function, which can be harmful to brain development. Along with the viral induction of neuroinflammation, other noninfectious conditions may interact to produce additional inflammation, such as the nutritional imbalance of fatty acids and polyunsaturated fatty acids and alcohol consumption during pregnancy. Additionally, transient thyrotoxicosis induced by SARS-CoV-2 with secondary autoimmune hypothyroidism has been reported, which could go undetected during pregnancy. Together, those factors may pose additional risk factors for SARS-CoV-2 infection impacting mechanisms of neural development such as synaptic pruning and neural circuitry formation. The present review discusses those conditions in the perspective of the understanding of risk factors that should be considered and the possible emergence of neurodevelopmental disorders in COVID-19-infected children.

Gut instincts: vitamin D/vitamin D receptor and microbiome in neurodevelopment disorders

The gut microbiome regulates a relationship with the brain known as the gut–microbiota–brain (GMB) axis. This interaction is influenced by immune cells, microbial metabolites and neurotransmitters. Recent findings show gut dysbiosis is prevalent in autism spectrum disorder (ASD) as well as attention deficit hyperactivity disorder (ADHD). There are previously established negative correlations among vitamin D, vitamin D receptor (VDR) levels and severity of ASD as well as ADHD. Both vitamin D and VDR are known to regulate homeostasis in the brain and the intestinal microbiome. This review summarizes the growing relationship between vitamin D/VDR signalling and the GMB axis in ASD and ADHD. We focus on current publications and summarize the progress of GMB in neurodevelopmental disorders, describe effects and mechanisms of vitamin D/VDR in regulating the microbiome and synoptically highlight the potential applications of targeting vitamin D/VDR signalling in neurodevelopment disorders.

Transgenerational inheritance of fetal alcohol exposure adverse effects on immune gene interferon-ϒ

Background

Alcohol exposures in utero have been shown to alter immune system functions in the offspring which persists into adulthood. However, it is not apparent why the in utero alcohol effect on the immune system persists into adulthood of fetal alcohol-exposed offspring. The objective of this study was to determine the long-term effects of fetal alcohol exposure on the production of interferon-ϒ (IFN-ϒ), a cytokine known to regulate both innate and adaptive immunity.

Methods

Isogenic Fisher 344 rats were bred to produce pregnant dams, which were fed with a liquid diet containing 6.7% alcohol between gestation days 7 and 21 and pair-fed with an isocaloric liquid diet or fed ad libitum with rat chow; their male and female offspring were used for the study. F1-F3 generation rats were used when they were 2 to 3 months old. Fetal alcohol exposure effects on the Ifn-ɣ gene was determined by measuring the gene promoter methylation and mRNA and protein expression in the spleen. Additionally, transgenerational studies were conducted to evaluate the germline-transmitted effects of fetal alcohol exposure on the Ifn-ɣ gene.

Results

Fetal alcohol exposure reduced the expression of Ifn-ɣ mRNA and IFN-ϒ protein while it increased the proximal promoter methylation of the Ifn-ɣ gene in both male and female offspring during the adult period. Transgenerational studies revealed that the reduced levels of Ifn-ɣ expression and increased levels of its promoter methylation persisted only in F2 and F3 generation males derived from the male germ line.

Conclusion

Overall, these findings provide the evidence that fetal alcohol exposures produce an epigenetic mark on the Ifn-ɣ gene that passes through multiple generations via the male germ line. These data provide the first evidence that the male germ line transmits fetal alcohol exposure's adverse effects on the immune system.

Role of zinc insufficiency in fetal alveolar macrophage dysfunction and RSV exacerbation associated with fetal ethanol exposure

BACKGROUND

We previously reported that maternal alcohol use significantly increases the risk of sepsis in premature and term newborns. In the mouse, fetal ethanol exposure results in an immunosuppressed phenotype for the alveolar macrophage (AM) and decreases bacterial phagocytosis. In pregnant mice, ethanol decreased AM zinc homeostasis, which contributed to immunosuppression and impaired AM phagocytosis. In this study, we explored whether ethanol-induced zinc insufficiency extended to the pup AMs and contributed to immunosuppression and exacerbated viral lung infections.

METHODS

C57BL/6 female mice were fed a liquid diet with 25% ethanol-derived calories or pair-fed a control diet with 25% of calories as maltose-dextrin. Some pup AMs were treated in vitro with zinc acetate before measuring zinc pools or transporter expression and bacteria phagocytosis. Some dams were fed additional zinc supplements in the ethanol or control diets, and then we assessed pup AM zinc pools, zinc transporters, and the immunosuppressant TGFβ1. On postnatal day 10, some pups were given intranasal saline or respiratory syncytial virus (RSV), and then AM RSV phagocytosis and the RSV burden in the airway lining fluid were assessed.

RESULTS

Fetal ethanol exposure decreased pup AM zinc pools, zinc transporter expression, and bacterial clearance, but in vitro zinc treatments reversed these alterations. In addition, the expected ethanol-induced increase in TGFβ1 and immunosuppression were associated with decreased RSV phagocytosis and exacerbated RSV infections. However, additional maternal zinc supplements blocked the ethanol-induced perturbations in the pup AM zinc homeostasis and TGFβ1 immunosuppression, thereby improving RSV phagocytosis and attenuating the RSV burden in the lung.

CONCLUSION

These studies suggest that, despite normal maternal dietary zinc intake, in utero alcohol exposure results in zinc insufficiency, which contributes to compromised neonatal AM immune functions, thereby increasing the risk of bacterial and viral infections.

Adverse health outcomes associated with fetal alcohol exposure: A systematic review focused on immune-related outcomes

Prenatal alcohol exposure (PAE) has well-known teratogenic effects on the developing fetus, potentially resulting in neurologic impairments. However, there is increasing interest regarding other potential adverse health outcomes related to prenatal alcohol exposure. The objective of this study was to undertake a systematic review to identify all the available clinical and preclinical literature investigating immune-related outcomes in offspring with PAE. A systematic review searching four electronic databases (PubMed, CINAHL, Web of Science, and Embase) was conducted. Potential articles were screened against strict inclusion/exclusion criteria. This review specifically focused on evaluating studies related to immune-related outcomes following PAE. Twelve clinical studies were included in the current review. Six included allergy outcomes, four included infection outcomes, and two studies included both. Thirty-nine preclinical studies were identified examining a wide range of immune outcomes. The current review provides some preliminary clinical evidence that PAE can influence immune function, including atopic allergy and infection outcomes. However, there was variability in results across studies, particularly in the atopy area. Preclinical studies demonstrated some changes in lymphocytes and cytokines in offspring following PAE. More research investigating the effects of PAE on immune responses is warranted.

Ethanol Exposure Impairs AMPK Signaling and Phagocytosis in Human Alveolar Macrophages: Role of Ethanol Metabolism

BACKGROUND

Chronic alcohol consumption impairs alveolar macrophage's (AM) function and increases risk for developing lung infection and pneumonia. However, the mechanism and metabolic basis of alcohol-induced AM dysfunction leading to lung infection are not well defined, but may include altered ethanol (EtOH) and reactive oxygen species metabolism and cellular energetics. Therefore, oxidative stress, endoplasmic reticulum (ER) stress, the formation of fatty acid ethyl esters [FAEEs, nonoxidative metabolites of EtOH], AMP-activated protein kinase (AMPK) signaling, and phagocytic function were examined in freshly isolated AM incubated with EtOH.

METHODS

AMs separated from bronchoalveolar lavage fluid samples obtained from normal volunteers were incubated with EtOH for 24 hours. AMPK signaling and ER stress were assessed using Western blotting, FAEEs by GC-MS, oxidative stress by immunofluorescence using antibodies to 4-hydroxynonenal, and phagocytosis by latex beads. Oxidative stress was also measured in EtOH-treated AMs with/without AMPK activator [5-aminoimidazole-4-carboxamide ribonucleotide (AICAR)] or inhibitor (Compound C), and in AMs incubated with FAEEs. mRNA expression for interleukins (IL-6 and IL-8), monocyte chemoattractant protein (MCP)-1, and transforming growth factor (TGF)-β was measured in AM treated with EtOH or FAEEs using RT-PCR.

RESULTS

EtOH exposure to AM increased oxidative stress, ER stress, and synthesis of FAEEs, decreased phosphorylated AMPK, and impaired phagocytosis. Attenuation or exacerbation of EtOH-induced oxidative stress by AICAR or Compound C, respectively, suggests a link between AMPK signaling, EtOH metabolism, and related oxidative stress. The formation of FAEEs may contribute to EtOH-induced oxidative stress as FAEEs also produced concentration-dependent oxidative stress. An increased mRNA expression of IL-6, IL-8, and MCP-1 by FAEEs is key finding to suggest a metabolic basis of EtOH-induced inflammatory response.

CONCLUSIONS

EtOH-induced impaired phagocytosis, oxidative stress, ER stress, and dysregulated AMPK signaling are plausibly associated with the formation of FAEEs and may participate in the pathogenesis of nonspecific pulmonary inflammation.

Environmental exposures during pregnancy: Mechanistic effects on immunity

In human studies, it is well established that exposures during embryonic and fetal development periods can influence immune health. Coupled with genetic predisposition, these exposures can alter lifetime chronic and infectious disease trajectory, and, ultimately, life expectancy. Fortunately, as research advances, mechanisms governing long-term effects of prenatal exposures are coming to light and providing the opportunity for intervention and risk reduction. For instance, human association studies have provided a foundation for the association of prenatal exposure to particulate matter with early immunosuppression and later allergic disease in the offspring. Only recently, the mechanisms mediating this response have been revealed and there is much we have yet to discover. Although cellular immune response is understood for many exposure scenarios, molecular pathways are still unidentified. This review will provide commentary and synthesis of the current literature regarding environmental exposures during pregnancy and mechanisms determining immune outcomes. Shared mechanistic features and current gaps in the state of the science are identified and discussed. To such purpose, we address exposures by their immune effect type: immunosuppression, autoimmunity, inflammation and tissue damage, hypersensitivity, and general immunomodulation.

Preconception paternal alcohol exposure exerts sex-specific effects on offspring growth and long-term metabolic programming

BACKGROUND

Although clinical data support an association between paternal alcohol use and deficits in child neurocognitive development, the relationship between paternal drinking and alcohol-induced growth phenotypes remains challenging to define. Using an established mouse model of chronic exposure, previous work by our group has linked preconception paternal alcohol use to sex-specific patterns of fetal growth restriction and placental dysfunction. The aim of the present study was to investigate the long-term impact of chronic preconception paternal alcohol use on offspring growth and metabolic programming.

RESULTS

Preconception paternal alcohol exposure induced a prolonged period of fetal gestation and an increased incidence of intrauterine growth restriction, which affected the male offspring to a greater extent than the females. While the female offspring of ethanol-exposed males were able to match the body weights of the controls within the first 2 weeks of postnatal life, male offspring continued to display an 11% reduction in weight at 5 weeks of age and a 6% reduction at 8 weeks of age. The observed growth deficits associated with insulin hypersensitivity in the male offspring, while in contrast, females displayed a modest lag in their glucose tolerance test. These metabolic defects were associated with an up-regulation of genes within the pro-fibrotic TGF-β signaling pathway and increased levels of cellular hydroxyproline within the livers of the male offspring. We observed suppressed cytokine profiles within the liver and pancreas of both the male and female offspring, which correlated with the up-regulation of genes in the LiverX/RetinoidX/FarnesoidX receptor pathways. However, patterns of gene expression were highly variable between the offspring of alcohol-exposed sires. In the adult offspring of alcohol-exposed males, we did not observe any differences in the allelic expression of Igf2 or any other imprinted genes.

CONCLUSIONS

The impact of paternal alcohol use on child development is poorly explored and represents a significant gap in our understanding of the teratogenic effects of ethanol. Our studies implicate paternal exposure history as an additional and important modifier of alcohol-induced growth phenotypes and challenge the current maternal-centric exposure paradigm.

Screening for prenatal alcohol exposure and corresponding short-term neonatal outcomes

Detection of prenatal alcohol exposure (PAE) is important for early intervention and treatment. The main purpose of this study was to compare 1.) PAE rates using the biomarker, phosphatidylethanol (PEth), in umbilical cord (UC) blood vs. ethyl glucuronide (EtG) in UC tissue, the standard of care, and 2.) Pregnancy characteristics and neonatal outcomes in newborns positive vs. negative for PAE biomarkers. We examined records of neonates born over a two-year span receiving UC-PEth dried blood spots testing at the time of delivery in addition to standard of care PAE screening (n = 146). UC-PEth testing had a higher PAE detection rate (26%) vs. UC tissue EtG (0%, p < 0.01). PAE was not associated with any neonatal dysmorphic features or short-term adverse outcomes. The absence of significant clinical findings for identifying PAE in neonates reinforces alcohol biomarker necessity. We conclude that UC-PEth may be a valuable test for assessing PAE at birth and in identifying infants at risk for developing fetal alcohol spectrum disorder.

Ethyl linolenate is elevated in meconium of very-low-birth-weight neonates exposed to alcohol in utero

BACKGROUND

The health implications of in utero alcohol exposure have been difficult to study in very-low-birth-weight newborns (VLBW) because of an inability to identify maternal alcohol exposure. Fatty acid ethyl esters (FAEEs) are elevated in meconium of alcohol-exposed term newborns. We hypothesized that meconium FAEEs would be similarly elevated in alcohol-exposed VLBW premature newborns.

METHODS

In a retrospective cohort study of 64 VLBW neonates, newborns were classified into Non-Exposed, Any Exposure, or Weekly Exposure groups based on an in-depth structured maternal interview. Meconium FAEE concentrations were quantified via gas chromatography mass spectrometry.

RESULTS

Alcohol exposure during Trimester 1 (Any Exposure) occurred in ~30% of the pregnancies, while 11% of the subjects reported drinking ≥ 1 drink/week (Weekly Exposure). Meconium ethyl linolenate was higher in Any Exposure (P = 0.01) and Weekly Exposure groups (P = 0.005) compared to the Non-Exposed VLBW group. There was a significant positive correlation between Trimester 1 drinking amounts and the concentration of meconium ethyl linolenate (P = 0.005). Adjusted receiver operating characteristic (ROC) curves evaluating ethyl linolenate to identify alcohol-exposed VLBW newborns generated areas under the curve of 88% with sensitivities of 86-89% and specificities of 83-88%.

CONCLUSION

Despite prematurity, meconium FAEEs hold promise to identify the alcohol-exposed VLBW newborn.

In utero alcohol effects on foetal, neonatal and childhood lung disease

Maternal alcohol use during pregnancy exposes both premature and term newborns to the toxicity of alcohol and its metabolites. Foetal alcohol exposure adversely effects the lung. In contrast to the adult "alcoholic lung" phenotype, an inability to identify the newborn exposed to alcohol in utero has limited our understanding of its effect on adverse pulmonary outcomes. This paper will review advances in biomarker development of in utero alcohol exposure. We will highlight the current understanding of in utero alcohol's toxicity to the developing lung and immune defense. Finally, we will present recent clinical evidence describing foetal alcohol's association with adverse pulmonary outcomes including bronchopulmonary dysplasia, viral infections such as respiratory syncytial virus and allergic asthma/atopy. With research to define alcohol's effect on the lung and translational studies accurately identifying the exposed offspring, the full extent of alcohol's effects on clinical respiratory outcomes of the newborn or child can be determined.

Inhibition of Mammary Cancer Progression in Fetal Alcohol Exposed Rats by β-Endorphin Neurons

BACKGROUND

Fetal alcohol exposure (FAE) increases the susceptibility to carcinogen-induced mammary cancer progression in rodent models. FAE also decreases β-endorphin (β-EP) level and causes hyperstress response, which leads to inhibition of immune function against cancer. Previous studies have shown that injection of nanosphere-attached dibutyryl cyclic adenosine monophosphate (dbcAMP) into the third ventricle increases the number of β-EP neurons in the hypothalamus. In this study, we assessed the therapeutic potential of stress regulation using methods to increase hypothalamic levels of β-EP, a neuropeptide that inhibits stress axis activity, in treatment of carcinogen-induced mammary cancer in fetal alcohol exposed rats.

METHODS

Fetal alcohol exposed and control Sprague Dawley rats were given a dose of N-Nitroso-N-methylurea (MNU) at postnatal day 50 to induce mammary cancer growth. Upon detection of mammary tumors, the animals were either transplanted with β-EP neurons or injected with dbcAMP-delivering nanospheres into the hypothalamus to increase β-EP peptide production. Spleen cytokines were detected using reverse transcription polymerase chain reaction assays. Metastasis study was done by injecting mammary cancer cells MADB106 into jugular vein of β-EP-activated or control fetal alcohol exposed animals.

RESULTS

Both transplantation of β-EP neurons and injection of dbcAMP-delivering nanospheres inhibited MNU-induced mammary cancer growth in control rats, and reversed the effect of FAE on the susceptibility to mammary cancer. Similar to the previously reported immune-enhancing and stress-suppressive effects of β-EP transplantation, injection of dbcAMP-delivering nanospheres increased the levels of interferon-γ and granzyme B and decreased the levels of epinephrine and norepinephrine in fetal alcohol exposed rats. Mammary cancer cell metastasis study also showed that FAE increased incidence of lung tumor retention, while β-EP transplantation inhibited lung tumor growth in both normal and fetal alcohol exposed rats.

CONCLUSIONS

Our results suggest that increase of β-EP production in the hypothalamus may serve as a potential therapeutic strategy for treating the cancer growth in patients with chronic stress and compromised immune function, such as the patients with FAE.

Maternal Alcohol Use During Pregnancy and Associated Morbidities in Very Low Birth Weight Newborns

BACKGROUND

We hypothesized that maternal alcohol use occurs in pregnancies that end prematurely and that in utero alcohol exposure is associated with an increased risk of morbidities of premature newborns.

METHODS

In an observational study of mothers who delivered very low birth weight newborns (VLBW) ≤1,500 g, maternal alcohol use was determined via a standardized administered questionnaire. We compared the effect of maternal drinking on the odds of developing late-onset sepsis (LOS), bronchopulmonary dysplasia (BPD), death, BPD or death, days on oxygen or any morbidity (either LOS, BPD or death). The effect of drinking amounts (light versus heavy) was also evaluated.

RESULTS

A total of 129 subjects who delivered 143 VLBW newborns were enrolled. Approximately 1 in 3 (34%) subjects reported drinking alcohol during the first trimester ("exposed"). Within the exposed group, 15% reported drinking ≥7drinks/week ("heavy") and 85% of the subjects reported drinking <7drinks/week ("light"). When controlling for maternal age, drug or tobacco use during pregnancy and neonatal gestational age, any drinking increased the odds of BPD or death and any morbidity. Furthermore, light or heavy drinking increased the odds of BPD or death and any morbidity, whereas heavy drinking increased the odds of LOS.

CONCLUSIONS

In utero alcohol exposure during the first trimester occurred in 34% of VLBW newborns. Maternal drinking in the first trimester was associated with significantly increased odds of neonatal morbidity. Further studies are warranted to determine the full effect of in utero alcohol exposure on the adverse outcomes of VLBW premature newborns.

Diabetic pregnancy activates the innate immune response through TLR5 or TLR1/2 on neonatal monocyte

Diabetes mellitus (DM) during pregnancy causes congenital malformation, macrosomia, respiratory distress syndrome, and other abnormalities in neonates, but whether maternal DM affects the neonatal innate immune system is unknown. Therefore we aimed to reveal the influence of DM in pregnancy on the toll-like receptor (TLR)-mediated innate immune response in neonates. Cord blood was collected after full-term vaginal or cesarean delivery and classified into a DM group (n=8) and non-DM (control) group (n=7). Mononuclear cells were harvested from cord blood by using density gradient centrifugation, after which anti-CD14 magnetic beads were used to isolate monocytes from the mononuclear population. After monocytes were cultured with lipopolysaccharide (TLR4 ligand), flagellin (TLR5 ligand), Pam3CSK4 (TLR1/TLR2 ligand), zymosan (TLR2/TLR6 ligand), or macrophage-activating lipopeptide (TLR2/TLR6 ligand) for 12h, the cytokine levels (interleukin [IL]-8, IL-6, IL-1β, IL-10, tumor necrosis factor alpha and IL-12) in the culture supernatants were measured. Compared with the control group, the DM group had higher concentrations of IL-8 (P=0.01) and tumor necrosis factor alpha (P=0.02) after monocyte cultures were stimulated with Pam3CSK4 and higher concentrations of IL-8 (P=0.01) after flagellin treatment. In contrast, stimulation with lipopolysaccharide, zymosan, or macrophage-activating lipopeptide did not lead to any difference in cytokine profiles between the two groups. These data indicate that maternal DM induces excessive inflammatory activation in neonates via a TLR5- or TLR1/2-mediated innate immune response.

Male germline transmits fetal alcohol epigenetic marks for multiple generations: a review

Alcohol exposure during fetal and early postnatal development can lead to an increased incidence of later life adult-onset diseases. Examples include central nervous system dysfunction, depression, anxiety, hyperactivity, and an inability to deal with stressful situations, increased infection and cancer. Direct effects of alcohol leading to developmental abnormalities often involve epigenetic modifications of genes that regulate cellular functions. Epigenetic marks carried over from the parents are known to undergo molecular programming events that happen early in embryonic development by a wave of DNA demethylation, which leaves the embryo with a fresh genomic composition. The proopiomelanocortin (Pomc) gene controls neuroendocrine-immune functions and is imprinted by fetal alcohol exposure. Recently, this gene has been shown to be hypermethylated through three generations. Additionally, the alcohol epigenetic marks on the Pomc gene are maintained in the male but not in the female germline during this transgenerational transmission. These data suggest that the male-specific chromosome might be involved in transmitting alcohol epigenetic marks through multiple generations.

Prenatal alcohol exposure alters steady-state and activated gene expression in the adult rat brain

BACKGROUND

Prenatal alcohol exposure (PAE) is associated with alterations in numerous physiological systems, including the stress and immune systems. We have previously shown that PAE increases the course and severity of arthritis in an adjuvant-induced arthritis (AA) model. While the molecular mechanisms underlying these effects are not fully known, changes in neural gene expression are emerging as important factors in the etiology of PAE effects. As the prefrontal cortex (PFC) and hippocampus (HPC) play key roles in neuroimmune function, PAE-induced alterations to their transcriptome may underlie abnormal steady-state functions and responses to immune challenge. This study examined brains from adult PAE and control females from our recent AA study to determine whether PAE causes long-term alterations in gene expression and whether these mediate the altered severity and course of arthritis in PAE females.

METHODS

Adult females from PAE, pair-fed (PF), and ad libitum-fed control (C) groups were injected with either saline or complete Freund's adjuvant. Animals were terminated at the peak of inflammation or during resolution (Days 16 and 39 postinjection, respectively); cohorts of saline-injected PAE, PF, and C females were terminated in parallel. Gene expression was analyzed in the PFC and HPC using whole-genome mRNA expression microarrays.

RESULTS

Significant changes in gene expression in both the PFC and HPC were found in PAE compared to controls in response to ethanol exposure alone (saline-injected females), including genes involved in neurodevelopment, apoptosis, and energy metabolism. Moreover, in response to inflammation (adjuvant-injected females), PAE animals showed unique expression patterns, while failing to exhibit the activation of genes and regulators involved in the immune response observed in control and pair-fed animals.

CONCLUSIONS

These results support the hypothesis that PAE affects neuroimmune function at the level of gene expression, demonstrating long-term effects of PAE on the central nervous system response under steady-state conditions and following an inflammatory insult.

Ferolla F, Hijano DR, Acosta PL, Erviti A, Polack FP. Alcohol during pregnancy worsens acute respiratory infections in children

AIM

This study explored whether alcohol consumption during pregnancy increased the risk of life-threatening respiratory infections in children.

METHODS

We prospectively evaluated children under the age of two years admitted to hospitals in Buenos Aires, Argentina, with severe acute respiratory infections during the winters of 2011 and 2012. Information on maternal alcohol consumption during the third trimester of pregnancy was collected using standardised questionnaires and categorised as never, low if it was once a week and high if it was equal or more than once a week.

RESULTS

Of the 3423 children hospitalised with acute respiratory infection, 2089 (63.7%) had respiratory syncytial virus (RSV). Alcohol consumption during the last trimester was reported by 398 mothers (12.4%) and categorised as low (n = 210, 6.5%) or high (n = 188, 5.9%). A greater effect on life-threatening respiratory infection, defined as oxygen saturation of or up to 87%, was observed with higher alcohol intake due to all viruses and specifically RSV in the logistic regression analyses. Alcohol consumption was strongly associated with life-threatening disease, particularly in boys whose adjusted odds ratio rose from 3.67 to 13.52 when their mothers drank alcohol.

CONCLUSION

Alcohol consumption during pregnancy was associated with life-threatening respiratory infections in boys.

Fetal Alcohol Exposure Reduces Dopamine Receptor D2 and Increases Pituitary Weight and Prolactin Production via Epigenetic Mechanisms

Recent evidence indicated that alcohol exposure during the fetal period increases the susceptibility to tumor development in mammary and prostate tissues. Whether fetal alcohol exposure increases the susceptibility to prolactin-producing tumor (prolactinoma) development in the pituitary was studied by employing the animal model of estradiol-induced prolactinomas in Fischer 344 female rats. We employed an animal model of fetal alcohol exposure that simulates binge alcohol drinking during the first two trimesters of human pregnancy and involves feeding pregnant rats with a liquid diet containing 6.7% alcohol during gestational day 7 to day 21. Control rats were pair-fed with isocaloric liquid diet or fed ad libitum with rat chow diet. Adult alcohol exposed and control female offspring rats were used in this study on the day of estrus or after estrogen treatment. Results show that fetal alcohol-exposed rats had increased levels of pituitary weight, pituitary prolactin (PRL) protein and mRNA, and plasma PRL. However, these rats show decreased pituitary levels of dopamine D2 receptor (D2R) mRNA and protein and increased pituitary levels of D2R promoter methylation. Also, they show elevated pituitary mRNA levels of DNA methylating genes (DNMT1, DNMT3b, MeCP2) and histone modifying genes (HDAC2, HDAC4, G9a). When fetal alcohol exposed rats were treated neonatally with a DNA methylation inhibitor 5-Aza deoxycytidine and/or a HDAC inhibitor trichostatin-A their pituitary D2R mRNA, pituitary weights and plasma PRL levels were normalized. These data suggest that fetal alcohol exposure programs the pituitary to increase the susceptibility to the development of prolactinomas possibly by enhancing the methylation of the D2R gene promoter and repressing the synthesis and control of D2R on PRL-producing cells.

Metabolic Consequences of Chronic Alcohol Abuse in Non-Smokers: A Pilot Study

An alcohol use disorder (AUD) is associated with an increased susceptibility to respiratory infection and injury and, upon hospitalization, higher mortality rates. Studies in model systems show effects of alcohol on mitochondrial function, lipid metabolism and antioxidant systems. The present study applied high-resolution metabolomics to test for these changes in bronchoalveolar lavage fluid (BALF) of subjects with an AUD. Smokers were excluded to avoid confounding effects and compliance was verified by cotinine measurements. Statistically significant metabolic features, differentially expressed by control and AUD subjects, were identified by statistical and bioinformatic methods. The results show that fatty acid and acylcarnitine concentrations were increased in AUD subjects, consistent with perturbed mitochondrial and lipid metabolism. Decreased concentrations of methyl-donor compounds suggest altered one-carbon metabolism and oxidative stress. An accumulation of peptides suggests proteolytic activity, which could reflect altered epithelial barrier function. Two metabolites of possible microbial origin suggest subclinical bacterial infection. Furthermore, increased diacetylspermine suggests additional metabolic perturbations, which could contribute to dysregulated alveolar macrophage function and vulnerability to infection. Together, the results show an extended metabolic consequence of AUD in the bronchoalveolar space.

Placental Fatty Acid ethyl esters are elevated with maternal alcohol use in pregnancies complicated by prematurity

The accumulation of fatty acid ethyl esters (FAEEs) in meconium of term newborns has been described as one potential biomarker of maternal alcohol use during pregnancy. FAEEs accumulate in multiple alcohol-exposed fetal tissues and in the placenta. Limited research has focused on the identification of the premature newborn exposed to alcohol in utero. We hypothesized that maternal alcohol use occurs in a significant proportion of premature deliveries and that this exposure can be detected as elevated placental FAEEs. The goals of this study were to 1) determine the prevalence of maternal alcohol use in the premature newborn and 2) investigate whether placental FAEEs could identify those newborns with fetal alcohol exposure. This prospective observational study evaluated 80 placentas from 80 women after premature delivery. Subjects were interviewed for alcohol intake and placental FAEEs were quantified via GC/MS. Receiver Operator Characteristic (ROC) Curves were generated to evaluate the ability of placental FAEEs to predict maternal drinking during pregnancy. Adjusted ROC curves were generated to adjust for gestational age, maternal smoking, and illicit drug use. 30% of the subjects admitted to drinking alcohol during pregnancy and approximately 14% answered questions indicative of problem drinking (designated AUDIT+). The specific FAEEs ethyl stearate and linoleate, as well as combinations of oleate + linoleate + linolenate (OLL) and of OLL + stearate, were significantly (p<0.05) elevated in placentas from AUDIT+ pregnancies. Adjusted ROC Curves generated areas under the curve ranging from 88–93% with negative predictive values of 97% for AUDIT+ pregnancies. We conclude that nearly one third of premature pregnancies were alcohol-exposed, and that elevated placental FAEEs hold great promise to accurately determine maternal alcohol use, particularly heavy use, in pregnancies complicated by premature delivery.

Effect of repeated alcohol exposure during the third trimester-equivalent on messenger RNA levels for interleukin-1β, chemokine (C-C motif) ligand 2, and interleukin 10 in the developing rat brain after injection of lipopolysaccharide

Microglia undergo maturation during the third trimester of human development (equivalent to the first 1-2 weeks of postnatal life in rodents), during which these cells may be particularly sensitive to insult. Alcohol exposure during this period can activate the neuroimmune system, an effect that may contribute to the pathophysiology of fetal alcohol spectrum disorders. Here, we investigated whether repeated alcohol exposure during the third trimester-equivalent in rats has a priming effect on the neuroimmune response to injection of bacterial lipopolysaccharide (LPS). Pups were exposed to alcohol in vapor chambers for 4 h daily from postnatal day (PD)2 to PD16 (peak blood alcohol concentrations ∼150 mg/dL). On PD17, rats were injected with either saline or LPS (50 μg/kg) and the frontal cortex, cerebellar vermis, and dentate gyrus were collected 2 h later. Messenger RNA (mRNA) levels for the pro-inflammatory agents interleukin 1β (IL-1β) and chemokine (C-C) motif ligand 2 (CCL2), as well as levels of the anti-inflammatory cytokine interleukin 10 (IL-10), were measured using reverse transcriptase polymerase chain reaction. LPS consistently increased IL-1β and CCL2 mRNA levels in the dentate gyrus, frontal cortex, and cerebellum of both male and female rats. Furthermore, the LPS-induced increase of IL-1β mRNA levels was significantly blunted in the frontal cortex of alcohol-exposed female rats. Conversely, LPS only minimally affected IL-10 mRNA expression and there were no significant differences between air- and alcohol-exposed rats. Taken together with the literature regarding the effect of third-trimester alcohol exposure on the neuroimmune system, our findings suggest that chronic exposure to lower levels is less disruptive to the neuroimmune system than binge-like exposure to high doses of alcohol.

Mechanisms underlying the effects of prenatal psychosocial stress on child outcomes: beyond the HPA axis

Accumulating evidence from preclinical and clinical studies indicates that maternal psychosocial stress and anxiety during pregnancy adversely affect child outcomes. However, knowledge on the possible mechanisms underlying these relations is limited. In the present paper, we review the most often proposed mechanism, namely that involving the HPA axis and cortisol, as well as other less well-studied but possibly relevant and complementary mechanisms. We present evidence for a role of the following mechanisms: compromised placental functioning, including the 11β-HSD2 enzyme, increased catecholamines, compromised maternal immune system and intestinal microbiota, and altered health behaviors including eating, sleep, and exercise. The roles of (epi)genetics, the postnatal environment and the fetus are also discussed. We conclude that maternal prenatal psychosocial stress is a complex phenomenon that affects maternal emotions, behavior and physiology in many ways, and may influence the physiology and functioning of the fetus through a network of different pathways. The review concludes with recommendations for future research that helps our understanding of the mechanisms by which maternal prenatal stress exerts its effect on the fetus.

The role of environmental factors in modulating immune responses in early life

The concept of immunological memory stipulates that past exposures shape present immune function. These exposures include not only specific antigens impacting adaptive immune memory but also conserved pathogen or danger associated molecular patterns that mold innate immune responses for prolonged periods of time. It should thus not come as a surprise that there is a vast range of external or environmental factors that impact immunity. The importance of environmental factors modulating immunity is most readily recognized in early life, a period of rapidly changing environments. We here summarize available data on the role of environment shaping immune development and from it derive an overarching hypothesis relating the underlying molecular mechanisms and evolutionary principles involved.

Prospective study of maternal alcohol intake during pregnancy or lactation and risk of childhood asthma: the Norwegian Mother and Child Cohort Study

BACKGROUND

Many women drink during pregnancy and lactation despite recommendations to abstain. In animals, alcohol exposure during pregnancy and lactation influences lung and immune development, plausibly increasing risk of asthma and lower respiratory tract infections (LRTIs). Studies in humans are few.

METHODS

In the Norwegian Mother and Child Cohort Study, we examined maternal alcohol intake during pregnancy and lactation in relation to risk of current asthma at 36 months (49,138 children), recurrent LRTIs by 36 months (39,791 children), and current asthma at 7 years (13,253 children). Mothers reported frequency and amount of alcohol intake each trimester and the first 3 months following delivery. We calculated adjusted relative risk (aRR), comparing children of drinkers to nondrinkers, using Generalized Linear Models.

RESULTS

A total of 31.8% of mothers consumed alcohol during first trimester, 9.7% during second trimester, and 15.6% during third trimester. Infrequent and low-dose prenatal alcohol exposure showed a modest statistically significant inverse association with current asthma at 36 months (aRRs ~ 0.85). No association was seen with the highest alcohol intakes during the first trimester when alcohol consumption was most common. RRs of maternal alcohol intake during pregnancy with recurrent LRTIs were ~1, with sporadic differences in risk for some metrics of intake, but without any consistent pattern. For current asthma at 7 years, similar inverse associations were seen as with current asthma at 36 months but were not statistically significant. Among children breastfed throughout the first 3 months of life, maternal alcohol intake during this time was not significantly associated with any of the 3 outcomes.

CONCLUSIONS

The low levels of alcohol exposure during pregnancy or lactation observed in this cohort were not associated with increased risk of asthma or recurrent LRTIs. The slight inverse associations of infrequent or low-dose prenatal alcohol exposure with asthma may not be causal.

Molecular changes during neurodevelopment following second-trimester binge ethanol exposure in a mouse model of fetal alcohol spectrum disorder: from immediate effects to long-term adaptation

Fetal alcohol spectrum disorder (FASD) is an umbrella term that refers to a wide range of behavioral and cognitive deficits resulting from prenatal alcohol exposure. It involves changes in brain gene expression that underlie lifelong FASD symptoms. How these changes are achieved from immediate to long-term effects, and how they are maintained, is unknown. We have used the C57BL/6J mouse to assess the dynamics of genomic alterations following binge alcohol exposure. Ethanol-exposed fetal (short-term effect) and adult (long-term effect) brains were assessed for gene expression and microRNA (miRNA) changes using Affymetrix mouse arrays. We identified 48 and 68 differentially expressed genes in short- and long-term groups, respectively. No gene was common between the 2 groups. Short-term (immediate) genes were involved in cellular compromise and apoptosis, which represent ethanol's toxic effects. Long-term genes were involved in various cellular functions, including epigenetics. Using quantitative RT-PCR, we confirmed the downregulation of long-term genes: Camk1g, Ccdc6, Egr3, Hspa5, and Xbp1. miRNA arrays identified 20 differentially expressed miRNAs, one of which (miR-302c) was confirmed. miR-302c was involved in an inverse relationship with Ccdc6. A network-based model involving altered genes illustrates the importance of cellular redox, stress and inflammation in FASD. Our results also support a critical role of apoptosis in FASD, and the potential involvement of miRNAs in the adaptation of gene expression following prenatal ethanol exposure. The ultimate molecular footprint involves inflammatory disease, neurological disease and skeletal and muscular disorders as major alterations in FASD. At the cellular level, these processes represent abnormalities in redox, stress and inflammation, with potential underpinnings to anxiety.

Transgenerational epigenetics and brain disorders

Neurobehavioral and psychiatric disorders are complex diseases with a strong heritable component; however, to date, genome-wide association studies failed to identify the genetic loci involved in the etiology of these brain disorders. Recently, transgenerational epigenetic inheritance has emerged as an important factor playing a pivotal role in the inheritance of brain disorders. This field of research provides evidence that environmentally induced epigenetic changes in the germline during embryonic development can be transmitted for multiple generations and may contribute to the etiology of brain disease heritability. In this review, we discuss some of the most recent findings on transgenerational epigenetic inheritance. We particularly discuss the findings on the epigenetic mechanisms involved in the heritability of alcohol-induced neurobehavioral disorders such as fetal alcohol spectrum disorders.

Alcohol exposure during late ovine gestation alters fetal liver iron homeostasis without apparent dysmorphology

High levels of alcohol (ethanol) exposure during fetal life can affect liver development and can increase susceptibility to infection after birth. Our aim was to determine the effects of a moderate level of ethanol exposure in late gestation on the morphology, iron status, and inflammatory status of the ovine fetal liver. Pregnant ewes were chronically catheterized at 91 days of gestation (DG; term ∼145 DG) for daily intravenous infusion of ethanol (0.75 g/kg maternal body wt; n = 8) or saline ( n = 7) over 1 h from 95 to 133 DG. At necropsy (134 DG), fetal livers were collected for analysis. Liver weight, general liver morphology, hepatic cell proliferation and apoptosis, perivascular collagen deposition, and interleukin ( IL) -1β, IL-6, or IL-8 mRNA levels were not different between groups. However, ethanol exposure led to significant decreases in hepatic content of ferric iron and gene expression of the iron-regulating hormone hepcidin and tumor necrosis factor ( TNF) -α (all P < 0.05). In the placenta, there was no difference in transferrin receptor, divalent metal transporter 1, and ferritin mRNA levels; however, ferroportin mRNA levels were increased in ethanol-exposed animals ( P < 0.05), and ferroportin protein tended to be increased ( P = 0.054). Plasma iron concentration was not different between control and ethanol-exposed groups; control fetuses had significantly higher iron concentrations than their mothers, whereas maternal and fetal iron concentrations were similar in ethanol-exposed animals. We conclude that daily ethanol exposure during the third-trimester-equivalent in sheep does not alter fetal liver morphology; however, decreased fetal liver ferric iron content and altered hepcidin and ferroportin gene expression indicate that iron homeostasis is altered.

Perinatal exposure to alcohol: implications for lung development and disease

In utero alcohol exposure dramatically increases the risk of premature delivery. However, the majority of premature and term newborns exposed to alcohol remain undetected by medical caregivers. There is a desperate need for reliable and accurate biomarkers of alcohol exposure for the term and premature newborn population. The inability to identify the exposed newborn severely limits our understanding of alcohol's pathophysiological effects on developing organs such as the lung. This chapter will review potential advancements in future biomarkers of alcohol exposure for the newborn population. We will discuss alcohol's effects on redox homeostasis and cellular development of the neonatal lung. Finally, we will present the evidence describing in utero alcohol's derangement of innate and adaptive immunity and risk for infectious complications in the lung. Continued investigations into the identification and understanding of the mechanisms of alcohol-induced alterations in the premature lung will advance the care of this vulnerable patient population.

Early developmental influences on hepatic organogenesis

The liver is the largest of the body's organs, with the greatest number of functions, playing a central role in coordinating metabolic homeostasis, nutrient processing and detoxification. The fetal liver forms during early gestation in response to a sequential array of distinct biological events, regulated by intrinsically programmed mechanisms and extracellular signals which instruct hepatic cells to either proliferate, differentiate or undergo apoptosis. A vast number of genes are involved in the initiation and control of liver development, many of which are sensitive to nutritional and hormonal regulation in utero. Moreover, liver mass is influenced by the gestational environment. Therefore, during periods of hepatic cell proliferation and differentiation, the developing fetal liver is sensitive to damage from both internal and external sources including teratogens, infection and nutritional deficiencies. For example, fetuses exposed to decreased materno-fetal nutrition during late gestation have a reduced liver mass, and/or perturbed liver function, which includes increased plasma LDL cholesterol and fibrinogen concentrations. These occur in conjunction with other risk factors present in the early stages of cardiovascular disease i.e. decreased glucose tolerance and insulin insensitivity in later life. Taken together, these findings suggest that liver mass, and later function, are essentially set in utero during fetal development-a process that is ultimately regulated by the intrauterine environment.

Male germline transmits fetal alcohol adverse effect on hypothalamic proopiomelanocortin gene across generations

BACKGROUND

Neurons containing proopiomelanocortin (POMC)-derived peptides, known to control stress axis, metabolic, and immune functions, have a lower function in patients with a family history of alcoholism, raising the possibility that alcohol effects on the POMC system may transmit through generations. Here we describe epigenetic modifications of Pomc gene that transmit through generation via male germline and may be critically involved in alcoholism-inherited diseases.

METHODS

Whether an epigenetic mechanism is involved in causing a Pomc expression deficit in fetal alcohol-exposed rats is studied by determining Pomc gene methylation, expression, and functional abnormalities and their normalization following suppression of DNA methylation or histone acetylation. Additionally, transgenerational studies were conducted to evaluate the germline-transmitted effect of alcohol.

RESULTS

Fetal alcohol-exposed male and female rat offspring showed a significant deficit in POMC neuronal functions. Associated with this was an increased methylation status of several CpG dinucleotides in the proximal part of the Pomc promoter region and altered level of histone-modifying proteins and DNA methyltransferases levels in POMC neurons. Suppression of histone deacetylation and DNA methylation normalized Pomc expression and functional abnormalities. Fetal alcohol-induced Pomc gene methylation, expression, and functional defects persisted in the F2 and F3 male but not in female germline. Additionally, the hypermethylated Pomc gene was detected in sperm of fetal alcohol-exposed F1 offspring that was transmitted through F3 generation via male germline.

CONCLUSIONS

Trangenerational epigenetic studies should spur new insight into the biological mechanisms that influence the sex-dependent difference in genetic risk of alcoholism-inherited diseases.

Effects of prenatal ethanol exposure on the lungs of postnatal lambs

Prenatal ethanol exposure increases collagen deposition and alters surfactant protein (SP) expression and immune status in lungs of near-term fetal sheep. Our objectives were to determine 1) whether these prenatal effects of repeated gestational ethanol exposure persist after birth and 2) whether surfactant phospholipid composition is altered following prenatal ethanol exposure. Pregnant ewes were chronically catheterized at 90 days of gestational age (DGA) and given a 1-h daily infusion of ethanol (0.75 g/kg, n = 9) or saline (n = 7) from 95 to 135 DGA; ethanol administration ceased after 135 DGA. Lambs were born naturally at full term (146 ± 0.5 DGA). Lung tissue was examined at 9 wk postnatal age for alterations in structure, SP expression, and inflammation; bronchoalveolar lavage fluid was examined for alterations in surfactant phospholipid composition. At 134 DGA, surfactant phospholipid concentration in amniotic fluid was significantly reduced (P < 0.05) by ethanol exposure, and the composition was altered. In postnatal lambs, there were no significant differences between treatment groups in birth weight, postnatal growth, blood gas parameters, and lung weight, volume, tissue fraction, mean linear intercept, collagen content, proinflammatory cytokine gene expression, and bronchoalveolar lavage fluid surfactant phospholipid composition. Although SP-A, SP-B, and SP-C mRNA levels were not significantly different between treatment groups, SP-D mRNA levels were significantly greater (P < 0.05) in ethanol-treated animals; as SP-D has immunomodulatory roles, innate immunity may be altered. The adverse effects of daily ethanol exposure during late gestation on the fetal lung do not persist to 2 mo after birth, indicating that the developing lung is capable of repair.

Delayed neonatal lung macrophage differentiation in a mouse model of in utero ethanol exposure

We have previously demonstrated that fetal ethanol exposure deranges the function and viability of the neonatal alveolar macrophage. Although altered differentiation of the alveolar macrophage contributes to pulmonary disease states within the adult lung, the effects of fetal ethanol exposure on the normal differentiation of interstitial to alveolar macrophage in the newborn lung are unknown. In the current study, using a mouse model of fetal ethanol exposure, we hypothesized that altered terminal differentiation of the neonatal interstitial to alveolar macrophage contributes to the observed cellular dysfunction in the ethanol-exposed newborn mouse. Control alveolar macrophage differentiation was characterized by increased expression of CD32/CD11b (P < or = 0.05) and increased in vitro phagocytosis of Staphylococcus aureus (P < or = 0.05) compared with interstitial macrophage. After in utero ethanol exposure, both alveolar and interstitial macrophage lacked the acquisition of CD32/CD11b (P < or = 0.05) and displayed impaired in vitro phagocytosis (P < or = 0.05). Ethanol significantly increased transforming growth factor-beta(1) (TGF-beta(1)) in the bronchoalveolar lavage fluid (P < or = 0.05), as well as in both interstitial and alveolar macrophages (P < or = 0.05). Oxidant stress contributed to the ethanol-induced changes on the interstitial and alveolar cells, since maternal supplementation with the glutathione precursor S-adenosylmethionine during ethanol ingestion normalized CD32/CD11b (P < or = 0.05), phagocytosis (P < or = 0.05), and TGF-beta(1) in the bronchoalveolar lavage fluid and macrophages (P < or = 0.05). Contrary to our hypothesis, fetal ethanol exposure did not solely impair interstitial to alveolar macrophage differentiation. Rather, fetal ethanol exposure impaired both neonatal interstitial and alveolar macrophage phagocytic function and differentiation. Increased oxidant stress and elevated TGF-beta(1) contributed to the impaired differentiation of both interstitial and alveolar macrophage.

Including a screening and brief alcohol intervention program in the care of the obstetric patient

Alcohol is the drug most commonly abused by pregnant women and the leading cause of preventable birth defects across the United States. Screening, Brief Intervention, and Referral for Treatment is a program developed by the Emergency Nurses Association that has demonstrated success in treating patients who have alcohol use disorders. This interventional program can be useful to perinatal nurses caring for pregnant women with alcohol use disorders in a variety of settings.

Fetal exposure to ethanol has long-term effects on the severity of influenza virus infections

Alcohol use by pregnant women is a significant public health issue despite well-described risks to the fetus including physical and intellectual growth retardation and malformations. Although clinical studies are limited, they suggest that in utero alcohol exposure also results in significant immune deficiencies in naive neonates. However, little is known about fetal alcohol exposure (FAE) effects on adult infections. Therefore, to determine the long-term effects of FAE on disease susceptibility and the adult immune system, we infected FAE adult mice with influenza virus. In this study, we demonstrate that mice exposed to ethanol during gestation and nursing exhibit enhanced disease severity as well as increased and sustained pulmonary viral titers following influenza virus infection. Secondary exposure to alcohol as an adult further exacerbates these effects. Moreover, we demonstrate that FAE mice have impaired adaptive immune responses, including decreased numbers of virus-specific pulmonary CD8 T cells, a decreased size and frequency of pulmonary B cell foci, and reduced production of influenza-specific Ab following influenza infection. Together, our results suggest that FAE induces significant and long-term defects in immunity and susceptibility to influenza virus infection and that FAE individuals could be at increased risk for severe and fatal respiratory infections.

Beta-endorphin neuronal cell transplant reduces corticotropin releasing hormone hyperresponse to lipopolysaccharide and eliminates natural killer cell functional deficiencies in fetal alcohol exposed rats

BACKGROUND

Natural killer (NK) cell dysfunction is associated with hyperresponse of corticotropin releasing hormone (CRH) to immune challenge and with a loss of beta-endorphin (BEP) neurons in fetal alcohol exposed animals. Recently, we established a method to differentiate neural stem cells into BEP neurons using cyclic adenosine monophosphate (cAMP)-elevating agents in cultures. Hence, we determined whether in vitro differentiated BEP neurons could be used for reversing the compromised stress response and immune function in fetal alcohol exposed rats.

METHODS

To determine the effect of BEP neuron transplants on NK cell function, we implanted in vitro differentiated BEP neurons into the paraventricular nucleus of pubertal and adult male rats exposed to ethanol or control in utero. The functionality of transplanted BEP neurons was determined by measuring proopiomelanocortin (POMC) gene expression in these cells and their effects on CRH gene expression under basal and after lipopolysaccaride (LPS) challenge. In addition, the effectiveness of BEP neurons in activating NK cell functions is determined by measuring NK cell cytolytic activity and interferon-gamma (IFN-gamma) production in the spleen and in the peripheral blood mononuclear cell (PBMC) following cell transplantation.

RESULTS

We showed here that when these in vitro differentiated BEP neurons were transplanted into the hypothalamus, they maintain biological functions by producing POMC and reducing the CRH neuronal response to the LPS challenge. BEP neuronal transplants significantly increased NK cell cytolytic activity in the spleen and in the PBMC and increased plasma levels of IFN-gamma in control and fetal alcohol exposed rats.

CONCLUSIONS

These data further establish the BEP neuronal regulatory role in the control of CRH and NK cell cytolytic function and identify a possible novel therapy to treat stress hyperresponse and immune deficiency in fetal alcohol exposed subjects.

Early-life environment, developmental immunotoxicology, and the risk of pediatric allergic disease including asthma

Incidence of childhood allergic disease including asthma (AD-A) has risen since the mid-20th century with much of the increase linked to changes in environment affecting the immune system. Childhood allergy is an early life disease where predisposing environmental exposures, sensitization, and onset of symptoms all occur before adulthood. Predisposition toward allergic disease (AD) is among the constellation of adverse outcomes following developmental immunotoxicity (DIT; problematic exposure of the developing immune system to xenobiotics and physical environmental factors). Because novel immune maturation events occur in early life, and the pregnancy state itself imposes certain restrictions on immune functional development, the period from mid-gestation until 2 years after birth is one of particular concern relative to DIT and AD-A. Several prenatal-perinatal risk factors have been identified as contributing to a DIT-mediated immune dysfunction and increased risk of AD. These include maternal smoking, environmental tobacco smoke, diesel exhaust and traffic-related particles, heavy metals, antibiotics, environmental estrogens and other endocrine disruptors, and alcohol. Diet and microbial exposure also significantly influence immune maturation and risk of allergy. This review considers (1) the critical developmental windows of vulnerability for the immune system that appear to be targets for risk of AD, (2) a model in which the immune system of the DIT-affected infant exhibits immune dysfunction skewed toward AD, and (3) the lack of allergy-relevant safety testing of drugs and chemicals that could identify DIT hazards and minimize problematic exposure of pregnant women and children.

Repeated ethanol exposure during late gestation alters the maturation and innate immune status of the ovine fetal lung

Little is known about the effects of fetal ethanol exposure on lung development. Our aim was to determine the effects of repeated ethanol exposure during late gestation on fetal lung growth, maturation, and inflammatory status. Pregnant ewes were chronically catheterized at 91 days of gestational age (DGA; term approximately 147 days). From 95-133 DGA, ewes were given a 1-h daily infusion of either 0.75 g ethanol/kg (n = 9) or saline (n = 8), with tissue collection at 134 DGA. Fetal lungs were examined for changes in tissue growth, structure, maturation, inflammation, and oxidative stress. Between treatment groups, there were no differences in lung weight, DNA and protein contents, percent proliferating and apoptotic cells, tissue and air-space fractions, alveolar number and mean linear intercept, septal thickness, type-II cell number and elastin content. Ethanol exposure caused a 75% increase in pulmonary collagen I alpha1 mRNA levels (P < 0.05) and a significant increase in collagen deposition. Surfactant protein (SP)-A and SP-B mRNA levels were approximately one third of control levels following ethanol exposure (P < 0.05). The mRNA levels of the proinflammatory cytokines interleukin (IL)-1beta and IL-8 were also lower (P < 0.05) in ethanol-exposed fetuses compared with controls. Pulmonary malondialdehyde levels tended to be increased (P = 0.07) in ethanol-exposed fetuses. Daily exposure of the fetus to ethanol during the last third of gestation alters extracellular matrix deposition and surfactant protein gene expression, which could increase the risk of respiratory distress syndrome after birth. Changes to the innate immune status of the fetus could increase the susceptibility of the neonatal lungs to infection.