Behavioral Abnormalities In Offspring Research Articles

Brain methylome remodeling selectively regulates neuronal activity genes linking to emotional behaviors in mice exposed to maternal immune activation

How early life experience is translated into storable epigenetic information leading to behavioral changes remains poorly understood. Here we found that Zika virus (ZIKV) induced-maternal immune activation (MIA) imparts offspring with anxiety- and depression-like behavior. By integrating bulk and single-nucleus RNA sequencing (snRNA-seq) with genome-wide 5hmC (5-hydroxymethylcytosine) profiling and 5mC (5-methylcytosine) profiling in prefrontal cortex (PFC) of ZIKV-affected male offspring mice, we revealed an overall loss of 5hmC and an increase of 5mC levels in intragenic regions, associated with transcriptional changes in neuropsychiatric disorder-related genes. In contrast to their rapid initiation and inactivation in normal conditions, immediate-early genes (IEGs) remain a sustained upregulation with enriched expression in excitatory neurons, which is coupled with increased 5hmC and decreased 5mC levels of IEGs in ZIKV-affected male offspring. Thus, MIA induces maladaptive methylome remodeling in brain and selectively regulates neuronal activity gene methylation linking to emotional behavioral abnormalities in offspring.

Restoring prefrontal cortical excitation-inhibition balance with cannabidiol ameliorates neurobehavioral abnormalities in a mouse model of neurodevelopmental disorders

Maternal immune activation (MIA) resulting from viral infections during pregnancy is linked to increased rates of neurodevelopmental disorders in offspring. However, the mechanisms underlying MIA-induced neurobehavioral abnormalities remain unclear. Here, we used a poly (I:C)-induced MIA mouse model to demonstrate the presence of multiple behavioral deficits in male offspring. Through RNA sequencing (RNA-seq), we identified significant upregulation of genes involved in axonogenesis, synaptogenesis, and glutamatergic synaptic neurotransmission in the mPFC of MIA mice. Electrophysiological analyses further revealed an excitatory-inhibitory (E/I) synaptic imbalance in mPFC pyramidal neurons, leading to hyperactivity in this brain region. Cannabidiol (CBD) effectively alleviated the behavioral abnormalities observed in MIA offspring by reducing glutamatergic transmission and enhancing GABAergic neurotransmission of mPFC pyramidal neurons. Activation of GPR55 by lipid lysophosphatidylinositol (LPI), an endogenous GPR55 agonist, specifically in the mPFC of healthy animals led to MIA-associated behavioral phenotypes, which CBD could effectively reverse. Moreover, we found that a GPR55 antagonist can mimic CBD's beneficial effects, indicating that CBD's therapeutic effects are mediated via the LPI-GPR55 signaling pathway. Therefore, we identified mPFC as a primary node of a neural network that mediates MIA-induced behavioral abnormalities in offspring. Our work provides insights into the mechanisms underlying the developmental consequences of MIA and identifies CBD as a promising therapeutic approach to alleviate these effects.

Long-lasting beneficial effects of maternal intake of sulforaphane glucosinolate on gut microbiota in adult offspring

Mounting evidence suggests the impact of maternal diet on the health of offspring. We reported that maternal diet of sulforaphane glucosinolate (SGS) could prevent behavioral abnormalities in offspring after maternal immune activation. The present study was designed to investigate whether the dietary intake of SGS during pregnancy and lactation influences the composition of gut microbiota in the offspring. The dietary intake of SGS during pregnancy and lactation caused significant changes in the α-diversity and β-diversity of gut microbiota in 3-week-old offspring (SGS-3W group) and 10-week-old offspring (SGS-10W group). The LEfSe algorithm identified several microbes as important phylotypes in the SGS-3W or SGS-10W groups. Predictive functional metagenomes showed that the maternal intake of SGS caused several KEGG pathways alterations with respect to the genetic information processing and metabolism. Furthermore, the plasma levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the SGS-10W group after the injection of lipopolysaccharide (LPS: 0.5 mg/kg) were significantly lower than those of the CON-10W group. It is noteworthy that there were positive correlations between the relative abundance of the genus Blautia and IL-6 (or TNF-α) in adult offspring. Moreover, there were sex differences of gut microbiota composition in offspring. In conclusion, these data suggest that the dietary intake of SGS during pregnancy and lactation might produce long-lasting beneficial effects in adult offspring through the persistent modulation of gut microbiota. It is likely that the modulation of gut microbiota by maternal nutrition may confer resilience versus vulnerability to stress-related psychiatric disorders in the offspring.

GUT-brain axis

In humans, epidemiological studies suggest that fetuses' exposure to maternal inflammation increases the likelihood of developing Autism Spectrum Disorder (ASD). We previously demonstrated that interleukin-17a (IL-17a) produced by Th17 cells (CD4+ T helper effector cells involved in multiple autoimmune and inflammatory diseases) is required in pregnant mice to induce behavioral abnormalities in offspring exposed to maternal immune activation (MIA). Furthermore, we and others showed that MIA-induced phenotypes in offspring require maternal intestinal bacteria that promote Th17 cell differentiation.

The effects of maternal SSRI exposure on the serotonin system, prefrontal protein expression and behavioral development in male and female offspring rats

Fluoxetine (FLX), a commonly used selective serotonin reuptake inhibitor, is often used to treat depression during pregnancy. However, prenatal exposure to FLX has been associated with a series of neuropsychiatric illnesses. The use of a rodent model can provide a clear indication as to whether prenatal exposure to SSRIs, independent of maternal psychiatric disorders or genetic syndromes, can cause long-term behavioral abnormalities in offspring. Thus, the present study aimed to explore whether prenatal FLX exposure causes long-term neurobehavioral effects, and identify the underlying mechanism between FLX and abnormal behaviors. In our study, 12/mg/kg/day of FLX or equal normal saline (NS) was administered to pregnant Sprague-Dawley (SD) rats (FLX = 30, NS = 27) on gestation day 11 till birth. We assessed the physical development and behavior of offspring, and in vivo magnetic resonance spectroscopy (MRS) was conducted to quantify biochemical alterations in the prefrontal cortex (PFC). Ex vivo measurements of brain serotonin level and a proteomic analysis were also undertaken. Our results showed that the offspring (male offspring in particular) of fluoxetine exposed mothers showed delayed physical development, increased anxiety-like behavior, and impaired social interaction. Moreover, down-regulation of 5-HT and SERT expression were identified in the PFC. We also found that prenatal FLX exposure significantly decreased NAA/tCr with 1H-MRS in the PFC of offspring. Finally, a proteomic study revealed sex-dependent differential protein expression. These findings may have translational importance suggesting that using SSRI medication alone in pregnant mothers may result in developmental delay in their offspring. Our results also help guide the choice of outcome measures in identifying of molecular and developmental mechanisms.

Environmental enrichment alters neurobehavioral development following maternal immune activation in mice offspring with epilepsy

Epilepsy is a chronic brain disease affecting millions of people worldwide. Anxiety-related disorders and cognitive deficits are common in patients with epilepsy. Previous studies have shown that maternal infection/immune activation renders children more vulnerable to neurological disorders later in life. Environmental enrichment has been suggested to improve seizures, anxiety, and cognitive impairment in animal models. The present study aimed to explore the effects of environmental enrichment on seizure scores, anxiety-like behavior, and cognitive deficits following maternal immune activation in offspring with epilepsy. Pregnant mice were treated with lipopolysaccharides-(LPS) or vehicle, and offspring were housed in normal or enriched environments during early adolescence to adulthood. To induce epilepsy, adult male and female offspring were treated with Pentylenetetrazol-(PTZ), and then anxiety-like behavior and cognitive functions were assessed. Tumor-necrosis-factor (TNF)-α and interleukin (IL) 10 were measured in the hippocampus of offspring. Maternal immune activation sex-dependently increased seizure scores in PTZ-treated offspring. Significant increases in anxiety-like behavior, cognitive impairment, and hippocampal TNF-α and IL-10 were also found following maternal immune activation in PTZ-treated offspring. However, there was no sex difference in these behavioral abnormalities in offspring. Environmental enrichment reversed the effects of maternal immune activation on behavioral and inflammatory parameters in PTZ-treated offspring. Overall, the present findings highlight the adverse effects of prenatal maternal immune activation on seizure susceptibility and psychiatric comorbidities in offspring. This study suggests that environmental enrichment may be used as a potential treatment approach for behavioral abnormalities following maternal immune activation in PTZ-treated offspring.

Galantamine improves enhanced impulsivity, impairments of attention and long-term potentiation induced by prenatal nicotine exposure to mice

Prenatal nicotine exposure (PNE) causes behavioral abnormalities in offspring, such as an enhancement of impulsivity and decrease in attention at adolescence. Here we examined the effects of galantamine (GAL) on the behavioral and electrophysiological changes induced by PNE in mice. Pregnant C57BL/6J mice were exposed to nicotine (0.2 mg/mL) dissolved in sweetened (2% saccharin) drinking water during gestational day 14 and perinatal day 0 (P0). At the ages of postnatal days 42–49 (P42-P49), female offspring displayed impulsivity in the cliff avoidance test and impairment of visual attention in the object-based attention test. Decrease of long-term potentiation (LTP) and extracellular glutamate levels were observed in the prefrontal cortex of PNE mice. Systemic treatment with GAL (1 mg/kg, s.c.), an allosteric potentiating ligand for the nicotinic acetylcholine receptor (nAChR) and a weak cholinesterase inhibitor, attenuated the enhancement of impulsivity and impairment of attention induced by PNE in mice. Further, GAL reversed the impairment of LTP induced by PNE in the prefrontal cortex of mice, although it failed to attenuate the decrease of extracellular glutamate levels. The effects of GAL were blocked by an α 7 nAChR antagonist, methyllycaconitine (1 mg/kg, i.p.). These results suggest that PNE during cortex development affects nicotinic cholinergic-dependent plasticity and formation of impulsivity and attention. Furthermore, GAL could be a useful drug for cognitive impairments-related to attention deficit hyperactivity disorder.

Dietary intake of glucoraphanin during pregnancy and lactation prevents the behavioral abnormalities in the offspring after maternal immune activation.

AimEpidemiological data suggest that maternal immune activation (MIA) plays a role in the etiology of neuropsychiatric disorders including autism spectrum disorder (ASD) and schizophrenia. However, there is no prophylactic nutrition that can prevent the onset of neurodevelopmental disorders in offspring after MIA. The aim of this study was undertaken to examine whether dietary intake of glucoraphanin (GF: the precursor of a natural anti‐inflammatory compound sulforaphane) can prevent the onset of behavioral abnormalities in offspring after MIA.MethodsOne percent of GF food pellet or normal food pellet was given into female mice during pregnancy and lactation (from E5 to P21). Saline (5 mL/kg/d) or poly(I:C) (5 mg/kg/d) was injected into pregnant mice from E12 to E17. Behavioral tests and immunohistochemistry of parvalbumin (PV) were performed in male offspring.ResultsDietary intake of GF during pregnancy and lactation prevented cognitive deficits and social interaction deficits in the juvenile offspring after MIA. Furthermore, dietary intake of GF during pregnancy and lactation prevented cognitive deficits in the adult offspring after MIA. Moreover, dietary intake of GF prevented the reduction of PV immunoreactivity in the medial prefrontal cortex of adult offspring after MIA.ConclusionThese data suggest that dietary intake of GF during pregnancy and lactation could prevent behavioral abnormalities in offspring after MIA.

Key role of soluble epoxide hydrolase in the neurodevelopmental disorders of offspring after maternal immune activation

Maternal infection during pregnancy increases risk of neurodevelopmental disorders such as schizophrenia and autism spectrum disorder (ASD) in offspring. In rodents, maternal immune activation (MIA) yields offspring with schizophrenia- and ASD-like behavioral abnormalities. Soluble epoxide hydrolase (sEH) plays a key role in inflammation associated with neurodevelopmental disorders. Here we found higher levels of sEH in the prefrontal cortex (PFC) of juvenile offspring after MIA. Oxylipin analysis showed decreased levels of epoxy fatty acids in the PFC of juvenile offspring after MIA, supporting increased activity of sEH in the PFC of juvenile offspring. Furthermore, expression of sEH (or EPHX2) mRNA in induced pluripotent stem cell-derived neurospheres from schizophrenia patients with the 22q11.2 deletion was higher than that of healthy controls. Moreover, the expression of EPHX2 mRNA in postmortem brain samples (Brodmann area 9 and 40) from ASD patients was higher than that of controls. Treatment with 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl)urea (TPPU), a potent sEH inhibitor, in juvenile offspring from prenatal day (P) 28 to P56 could prevent cognitive deficits and loss of parvalbumin (PV) immunoreactivity in the medial PFC of adult offspring after MIA. In addition, dosing of TPPU to pregnant mothers from E5 to P21 could prevent cognitive deficits, and social interaction deficits and PV immunoreactivity in the medial prefrontal cortex of juvenile offspring after MIA. These findings suggest that increased activity of sEH in the PFC plays a key role in the etiology of neurodevelopmental disorders in offspring after MIA. Therefore, sEH represents a promising prophylactic or therapeutic target for neurodevelopmental disorders in offspring after MIA.

Risk for Childhood Internalizing and Externalizing Behavior Problems in the Context of Prenatal Alcohol Exposure: A Meta-Analysis and Comprehensive Examination of Moderators.

Prenatal alcohol exposure (PAE) is associated with a constellation of physical, neurocognitive, and behavioral abnormalities in offspring. The presence of internalizing (e.g., anxiety, mood disorders) and externalizing (e.g., oppositional defiant and conduct disorders) behavior problems has devastating and often long-lasting impacts on children, adolescents, and their families. The present meta-analysis explored the strength of the association between PAE and behavior problems, as well as factors that increase or mitigate risk. The current meta-analysis included 65 studies comparing children and adolescents with PAE to non- or light-exposed controls and attention-deficit/hyperactivity disorder (ADHD) samples, on a variety of internalizing and externalizing behavior outcomes. Results indicated that individuals with PAE are at increased risk for internalizing (d=0.71, medium effect) and externalizing (d=0.90, large effect) problems compared to control samples. The occurrence of total behavior problems was similar to that seen in ADHD samples. The strength of the association between internalizing and externalizing behavior problems and PAE was significantly moderated by several distinct sample characteristics, such as sample age, socioeconomic status, severity of exposure, and type of behavior problem. These findings further our understanding of the behavior problems experienced by children and adolescents with PAE.

Expression of apoptosis-regulatory genes in the hippocampus of rat neonates born to mothers with diabetes.

Diabetes during pregnancy impairs the development of the central nervous system (CNS) and causes cognitive and behavioral abnormalities in offspring. However, the exact mechanism by which the maternal diabetes affects the development of the brain remains to be elucidated. The aim of the present study was to investigate the effects of maternal diabetes in pregnancy on the expression of Bcl-2 and Bax genes and the numerical density of degenerating dark neurons (DNs) in the hippocampus of offspring at the first postnatal two weeks. Wistar female rats were maintained diabetic from a week before pregnancy through parturition and male offspring was sacrificed at P0, P7, and P14. Our findings demonstrated a significant down-regulation in the hippocampal expression of Bcl-2 in the diabetic group newborns (P<0.05). In contrast, the mRNA expression of Bax was markedly up-regulated in the offspring born to diabetic dams at all of studied time-points (P<0.05). Moreover, we found a striking increase in the numerical density of DNs in the various subfields of hippocampus of diabetic group pups (P<0.05). The results of the present study revealed that maternal hyperglycemia during gestational period may result in disturbances in the expression of Bcl-2 and Bax genes as two important genes in neuronal apoptosis regulation and induces the production of DNs in the developing hippocampus of neonatal rats. These disturbances may be a reason for the cognitive, structural, and behavioral anomalies observed in offspring born to diabetic mothers. Furthermore, the control of maternal glycaemia by insulin administration in most cases normalized these negative impacts.

The majority of murine γδ T cells at the maternal-fetal interface in pregnancy produce IL-17.

Compared with lymphoid tissues, the immune cell compartment at mucosal sites is enriched with T cells bearing the γδ T-cell receptor (TCR). The female reproductive tract, along with the placenta and uterine decidua during pregnancy, are populated by γδ T cells predominantly expressing the invariant Vγ6(+)Vδ1(+) receptor. Surprisingly little is understood about the function of these cells. We found that the majority of γδ T cells in the non-pregnant uterus, pregnant uterus, decidua and placenta of mice express the transcription factor RORγt and produce interleukin-17 (IL-17). In contrast, IFNγ-producing γδ T cells were markedly reduced in gestational tissues compared with uterine-draining lymph nodes and spleen. Both uterine-resident invariant Vγ6(+) and Vγ4(+) γδ T cells which are more typically found in lymphoid tissues and circulating blood, were found to express IL-17. Vγ4(+) γδ T cells were particularly enriched in the placenta, suggesting a pregnancy-specific recruitment or expansion of these cells. A small increase in IL-17-producing γδ T cells was observed in allogeneic compared with syngeneic pregnancy, suggesting a contribution to regulating the maternal response to paternally-derived alloantigens. However, their high proportions also in non-pregnant uteri and gestational tissues of syngeneic pregnancy imply a role in the prevention of intrauterine infection or quality control of fetal development. These data suggest the need for a more rigorous evaluation of the role of IL-17 in sustaining normal pregnancy, particularly as emerging data points to a pathogenic role for IL-17 in pre-eclampsia, pre-term birth, miscarriage and maternal immune activation-induced behavioral abnormalities in offspring.

In Utero Bisphenol A Exposure Induces Abnormal Neuronal Migration in the Cerebral Cortex of Mice

Bisphenol A (BPA) has been known to have endocrine-disrupting activity to induce reproductive and behavioral abnormalities in offspring of laboratory animal species. However, morphological basis of this abnormality during brain development is largely unknown. Cerebral cortex plays a crucial role in higher brain function, and its precisely laminated structure is formed by neuronal migration. In the present study, transfecting a plasmid (pCAG-mCherry) by in utero electroporation (IUE), we visualized developing neurons and investigated the possible effects of in utero BPA exposure on neuronal migration. Pregnant mice were exposed to BPA by osmotic pump at estimated daily doses of 0, 40 (BPA-40), or 400 (BPA-400) μg/kg from embryonic day 14.5 (E14.5) to E18.5. IUE was performed at E14.5 and neuronal migration was analyzed at E18.5. Compared with the control group, neuronal migration in the cortical plate was significantly decreased in the BPA-40 group; however, there was no significant difference in the BPA-400 group. Among several neuronal migration-related genes and cortical layer-specific genes, TrkB in the BPA-400 group was found significantly upregulated. In conclusion, in utero exposure to low BPA dose was found to disrupt neuronal migration in the cerebral cortex in a dose-specific manner.

Prenatal family adversity and maternal mental health and vulnerability to peer victimisation at school

Prenatal stress has been shown to predict persistent behavioural abnormalities in offspring. Unknown is whether prenatal stress makes children more vulnerable to peer victimisation. The current study is based on the Avon Longitudinal Study of Parents and Children, a prospective community-based study. Family adversity, maternal anxiety and depression were assessed at repeated intervals in pregnancy and the postnatal period. Parenting, partner conflict and temperament were measured at preschool age. Peer victimisation was assessed using multiple informants (child, parent, teacher) at primary school age (between ages 7 and 10). Prenatal severe family adversity and maternal mental health directly increased the risk of victimisation at school even when controlled for postnatal family adversity and maternal mental health, parenting, partner conflict and temperament. Effects were found to be independent of sources of information of peer victimisation. Partner conflict and maladaptive parenting also independently increased the risk of peer victimisation. Experiences in pregnancy may affect the developing foetus and increase vulnerability to be victimised by peers. Conflict between parents and their parenting further increase the risk of being victimised by peers at school.

Maternal immune stimulation during pregnancy affects adaptive immunity in offspring to promote development of TH17 cells

Behavioral abnormalities in offspring of murine dams that receive immune stimulation with (poly)I:C during pregnancy are well-documented. In this prenatal model, (poly)I:C-induced maternal cytokines, particularly IL-6, appear involved in the etiology of the behavioral abnormalities. While much has been published on the abnormal behaviors of offspring in this model, much less is known about how maternal immune stimulation affects the adaptive immune system of the offspring, and its possible role in the observed pathophysiology. In the present study, pregnant dams were stimulated with (poly)I:C at E12, and 24 h later cytokine levels were measured in maternal sera and amniotic fluids. Lymphocytes from offspring were also analyzed for T Helper (TH) cell subsets. The results demonstrate that lymphocytes from offspring of pregnant dams stimulated with (poly)I:C develop into TH17 cells upon in vitro activation. This preferential TH17 cell differentiation occurs in offspring of pregnant dams with an immunological “memory” phenotype, but not in offspring of immunologically “naive” dams. Comparable levels of IL-6 were found in the sera of immune and naïve pregnant dams, however, there was a disparity between levels of IL-6 in maternal sera and amniotic fluids of (poly)I:C-injected dams. In matings between IL-6 KO dams (IL-6 −/−) and wild-type males (IL-6 +/+) there was no IL-6 in sera from (poly)I:C-injected dams, but there were high levels of IL-6 in their amniotic fluids. Analysis of supernatants of cultured placental cell preparations from these IL-6 KO dams confirmed that the IL-6 was produced from the fetal (IL-6 +/−) component, and heterozygous IL-6 +/− offspring could also produce IL-6.

Course of Psychiatric Disorders in Pregnancy: Dilemmas in Pharmacologic Management

Although it is generally believed that pregnancy is a time of emotional well-being, many women develop or have a recurrence of psychiatric illness during this time. The risks associated with leaving a woman untreated during pregnancy are potentially substantial and must be weighed against the risks of exposing the fetus to the potentially teratogenic medications. Large prospective and retrospective studies suggest a relative safety of use of tricyclic antidepressants during pregnancy. Data available for neuroleptics, lithium, benzodiazepines, and the anticonvulsants valproic acid and carbamazepine, although mixed, point to increased risks of congenital malformations in the children of mothers exposed to these agents in the first trimester of pregnancy. Very little is known about the behavioral abnormalities in offspring of mothers exposed to these agents. Animal studies suggest changes in brain receptor number and function in the offspring of mothers on a variety of psychotropic drugs studied to date. The few human studies do not suggest long term effects, but given the very limited data, no definitive conclusions can be drawn. Large epidemiologic follow-up studies of children exposed to medication in utero may help clarify questions relating to behavioral changes and thus help guide clinical decisions.