Mouse Dams Research Articles

Prenatal exposure to the probiotic Lactococcus lactis decreases anxiety-like behavior and modulates cortical cytoarchitecture in a sex specific manner.

Development of the cerebral cortex may be influenced by the composition of the maternal gut microbiota. To test this possibility, we administered probiotic Lactococcus lactis in drinking water to mouse dams from day 10.5 of gestation until pups reached postnatal day 1 (P1). Pups were assessed in a battery of behavioral tests starting at 10 weeks old. We found that females, but not males, exposed to probiotic during prenatal development spent more time in the center of the open field and displayed decreased freezing time in cue associated learning, compared to controls. Furthermore, we found that probiotic exposure changed the density of cortical neurons and increased the density of blood vessels in the cortical plate of P1 pups. Sex-specific differences were observed in the number of mitotic neural progenitor cells, which were increased in probiotic exposed female pups. In addition, we found that probiotic treatment in the latter half of pregnancy significantly increased plasma oxytocin levels in mouse dams, but not in the offspring. These results suggest that exposure of naïve, unstressed dams to probiotic may exert sex-specific long-term effects on cortical development and anxiety related behavior in the offspring.

Postnatal Growth Restriction In Mice Alters Cardiac Mitochondrial Energetics

Postnatal growth-restriction (PGR) is associated with increased risk of cardiovascular mortality. We hypothesize that nutrient restriction alters metabolism leading to cardiac failure. PURPOSE: To determine the effect of PGR on mitochondrial respiratory capacity (JO2). METHODS: FVB mouse dams were fed a control(CON: 20% protein), or a low-protein(LP: 8% protein) isocaloric diet 2-weeks before mating. LP-dams produce 18% less milk and pups nursed by LP-dams undergo growth restriction. At postnatal day (PN) 1, pups born to dams fed the CON diet were crossed to LP-dams(PUN; postnatally undernourished) or a different CON-dam. At PN21, all mice were weaned to the CON-diet. On PN22 or PN80, mice were weighed, euthanized, and hearts removed. Hearts were weighed and cardiac mitochondria were isolated via differential centrifugation. Respiration was measured through high-resolution respirometry in the presence of 5 mM pyruvate and 1 mM L-malate(PM). Two-way ANOVAs were performed with the main effects of diet (CON vs. PUN) and age(PN22 vs. PN80) to compare, body-mass, heart-mass, and JO2. An α level of 0.05 was set a priori, and if necessary, a Tukey’s HSD post hoc test was used for multiple comparisons. RESULTS: PGR caused significant diet and age effects (p<.001) on final body-mass between CON (PN22: 12.01±0.83g; PN80: 23.51±2.95g) and PUN groups (PN22: 8.45±0.61g; PN80: 21.32±3.42g). Heart-mass was also significantly reduced (p<.001) in PUN (PN22: 0.06±0.01g; PN80: 0.11±0.012g) compared to CON (PN22: 0.08±0.007g; PN80: 0.12±0.01g) across the lifespan. LEAK state JO2 was significantly higher (p<.001) at both time-points in PUN (PN22: 46.48±4.25nmol/mg/min, PN80: 48.74±8.34nmol/mg/min) compared to CON (PN22: 36.15±5.60nmol/mg/min, PN80: 38.23±2.74nmol/mg/min). The respiratory control ratio (RCR) was significantly reduced (p=0.0005) in PUN (PN22: 7.81±0.48, PN80: 7.32±1.48) compared to CON (PN22: 9.25±0.73, PN80: 9.14±0.74). CONCLUSIONS: PGR decreased body and heart-mass across the life span and increased LEAK state JO2 in the presence of PM, indicating mitochondrial impairment at PN22 and PN80. PGR caused reductions in RCR, which may cause CVD, thus PGR increases CVD risk through uncoupling of mitochondria. Exercise may improve mitochondrial function in PGR mouse hearts.

Restriction and hyperlipidic diets during pregnancy, lactation and adult life modified the expression of dopaminergic system related genes both in female mice and their adult offspring

The neurocircuitry underlying hunger, satiety, motivation to eat and food reward is complex, however a lot of mechanisms are still unknown. Two main cerebral areas are responsible for controlling feeding through hunger and food reward: the hypothalamus (HPT) and the ventral tegmental area (VTA), respectively. The dopaminergic system modulates both these areas and is essential to control food ingestion. Therefore, we aim to evaluate the effects of restrictive and hyperlipidic diets during pregnancy, lactation and during adult life of the offspring, on the expression of dopaminergic system genes in VTA and HPT of mice dams and their adult male offspring. We also measured diets’ effect in locomotor activity in the open field (OF) test. Female mice were divided into control (CONT), restriction (RD) and hyperlipidic (HD) dietary groups, and mated with isogenic male mice. On the 9th postpartum day (PPD), dams were tested in the OF, and on the 22nd PPD cerebral areas were collected. After weaning, the offspring also were divided into one of three diet groups, independently of the diets provided to their dams. In the 80th PPD, the offspring was tested in the OF, and at 100th PPD, VTA and HPT were collected. Gene expression was analyzed by quantitative reverse transcription real-time polymerase chain reaction. The correlation between gene expression and locomotor activity was also assessed. In dams’ VTA, both diets upregulated the expression of Th, Slc6a3/Dat1, Drd1 and Drd2 genes. In opposition, in the offspring the maternal diet was associated with a reduction in Th and Ddc gene expression. In the HPT, mice dams that received restriction or hyperlipidic diets had increased Th mRNA levels, but reduced the expression of Drd4 gene. The offspring diet had no effect on the expression of the studied genes in their adult lives. Both diets increased mice dam’s locomotion in the OF, however none of them altered the offspring locomotor activity. We detected a positive correlation between the duration of total locomotion in the OF and Slc6a3/Dat1 gene expression in VTA of mice dams. In the HPT, a negative correlation of locomotion and Drd4 mRNA levels, and a positive correlation with Th gene expression was observed. Our results show that restriction and hyperlipidic diets alter mice dams’ locomotor activity in the OF and modify the expression of dopaminergic system genes in VTA and HPT of mice dams and in VTA of the offspring.

Maternal Exercise Improves High-Fat Diet-Induced Metabolic Abnormalities and Gut Microbiota Profiles in Mouse Dams and Offspring.

Early-life overnutrition programs increased risks of metabolic disorders in adulthood. Regular exercise has been widely accepted to be an effective measure to maintain metabolic health. However, the intergenerational effects of maternal exercise and the specific mechanism are largely unclear. Our objective was to investigate whether maternal exercise could alleviate the metabolic disturbances induced by early-life overnutrition in both dams and offspring and to explore the role of gut microbiota in mediating the effects. C57BL/6 female mice were randomly divided into three groups: the control group, which were fed a normal control diet; high-fat group, which received a high-fat diet; and high-fat with exercise intervention group, which was fed a high-fat diet and received a voluntary wheel running training. The diet intervention started from 3 weeks prior to mating and lasted throughout pregnancy and lactation. The exercise intervention was only prior to and during pregnancy. The male offspring got free access to normal chow diet from weaning to 24 weeks of age. Glucose tolerance test and biochemical parameters were detected in dams at weaning and offspring at 8 and 24 weeks of age. Their cecal contents were collected for the 16 s rDNA amplicon sequencing. The results showed that maternal high-fat diet resulted in significant glucose intolerance, insulin resistance, and lipid profiles disorders in both dams and offspring. Maternal exercise markedly improved insulin sensitivity in dams and metabolic disorders in offspring from young into adulthood. The decrease in unfavorable bacteria and the persistent enrichment of short-chain fatty acids-producers from mothers to adult offspring, particularly the genus Odoribacter, were all associated with the improvement of metabolism by maternal exercise. Overall, maternal exercise could significantly mitigate the detrimental effects of a maternal high-fat diet on metabolism in both dams and male offspring. The continuous alterations in gut microbiota might be a critical factor in deciphering the metabolic benefits of maternal exercise, which provides some novel evidence and targets for combating metabolic diseases.

The Effect of Choline on DNA Methylation in the Hippocampus of the Offspring of Gestational Diabetes Mellitus (GDM) Mice

Abstract Objectives The objective of this project is to determine the effects of choline supplementation on DNA methylation in the hippocampus of the offspring from mouse dams with GDM. Methods In this study, female mice were divided into four groups: high fat (HF) feeding (to induce GDM), HF with choline supplementation, normal fat (NF) control and NF with choline supplementation. The experimental groups followed their diets and supplements for 4 weeks before timed mating and throughout gestation. Thereafter, they were fed the NF diet during lactation. After weaning, the offspring were fed the HF diet for 6 weeks before dissection. Brain hippocampus was then dissected for DNA extraction and global DNA methylation analysis. Results Global DNA methylation was increased in the NF choline supplemented group versus the NF control group (P = 0.056); however, there were no differences between the HF choline versus the HF or NF control groups (P = 0.992). Conclusions In summary, there was an interaction between maternal HF feeding and choline supplementation in influencing global DNA methylation. Maternal HF feeding eliminated the increase in offspring hippocampal DNA methylation by choline supplementation observed under the NF feeding condition. Funding Sources NIGMS.

Pre-Conception Avocado Powder Diet Decreases Fetal Viability Despite Increasing Placental Energetics in C57BL/6J Mice

Abstract Objectives To investigate the effects of commercial avocado powder (Hass variety) during pre-conception and gestation on metabolic and reproductive aspects of C57BL/6J mice dams. Methods Female C57BL/6J mice were kept on either a control (AIN 93; CON) or avocado (dextrose and sucrose replacement with 25% commercial avocado power; AVO) isoenergetic diet for 6 weeks prior to conception and during pregnancy (n = 8 per group). Body weight and dietary intake were daily recorded. At day 17 of pregnancy (E17), an intraperitoneal glucose tolerance test (IPGTT) was done. At E18, dams were euthanized by cervical dislocation. Blood was collected for lipid analysis. Maternal liver, placental and foetal weights and sexing were recorded. 1H Nuclear Magnetic Resonance metabolomics was performed in maternal liver and placenta. Results Pre-conception body weight was higher in AVO damns despite similar dietary intake. At E1, average weight was similar in both groups, ∼21 g. AVO diet promoted a hypolipidemic effect where dams showed a tendency to reduce triacylglycerol, total cholesterol and VLDL in 27% and LDL in 43%. AVO dams presented a significant 6% increase in the AUC in the IPGTT (P &amp;lt; 0.05). Body weight at E18 of AVO was 16% lower than the CON dams (P &amp;lt; 0.05). Fetal, placental weights and placental efficiency were similar between groups. However, AVO dams had 25% less viable fetuses and more number of reabsorption spots (P &amp;lt; 0.05). Liver metabolite profile from AVO dams were similar to CON, except for a significant 2-fold increase in glucose and 1.6-fold increase in the fumarate: succinate ratio. Placentas from male fetuses were more susceptible to changes in metabolites compared to female's, in both groups. Male placentas from AVO compared to CON dams had significant increase in methionine, phenylalanine and 3-hydroxybutyrate and increased glucose, lactate and glutamate contents (P &amp;lt; 0.09). Female placentas from AVO dams showed higher contents of AMP, IMP (P &amp;lt; 0.05) and lactate (P &amp;lt; 0.09). A significant interaction between diet and sex for choline content was found, with an increase in its content in male placenta from AVO. Conclusions The hypolipidemic effect of AVO diet might have contributed to its negative effects on reproduction. Whilst, placenta from both sexes seem to be energetically competent and with high availability of methyl donors. Funding Sources CAPES and FAPERJ.

Maternal obesity modulates both the renin–angiotensin system in mice dams and fetal adiposity

Obesity is a chronic multifactorial disease and is currently a public health problem. Maternal obesity during pregnancy is more dangerous as it impairs the health of the mother and future generations. Obesity leads to several metabolic disorders. Since white adipose tissue is an endocrine tissue, obesity often leads to disordered secretion of inflammatory, glycemic, lipid and renin–angiotensin system (RAS) components. The RAS represents a link between obesity and its metabolic consequences. Therefore, our goal was to evaluate the possible changes caused by a high-fat diet in RAS-related receptor expression in the uterus and placenta of pregnant mice and determine the underlying effects of these changes in the fetuses’ body composition. Breeding groups were formed after obesity induction by high-fat (HF) diet. Dams and fetuses were euthanized on the 19th day of the gestational period. The HF diet effectively induced obesity, glucose intolerance and insulin resistance in mice. Fetuses born from HF dams showed increased body weight and adiposity. Both results were accompanied by increased AT1R expression in placenta and uterus together with increased angiotensin-converting enzyme expression in the uterus and a decreased expression of MAS1 in placenta of HF dams. These results suggest a link between RAS, maternal obesity induced by HF diet and the fetuses’ body adiposity. This new path now can be more thoroughly explored.

Intestinal commensal bacteria promote AT2 self-renewal and AT1 differentiation in an IL-22 dependent fashion and prepare the newborn to fight potentially fatal respiratory pathogens

Abstract We demonstrated that disruption of intestinal commensal bacteria with antibiotics (ABX) severely diminished the levels of cytokine interleukin (IL)-22 in the newborn lung and rendered the ABX-exposed newborn mice susceptible post challenge with Streptococcus pneumoniae (S. pneumoniae). These experimental data suggest that colonization by intestinal commensal bacteria is vital for newborn’s lung defense against respiratory pathogens. Pregnant mouse dams were treated with ABX, and newborn mice were challenged with intratracheal S. pneumoniae (on postnatal day 5). Lungs were harvested and stained. AT2 cells and fibroblast harvested from ABX-treated or ABX-free newborn mice were cultured in matrigel to generate alveolar organoids. After harvest, the organoids were stained. To test the role of IL-22 signaling, Il22rafl/fl mice were bred with SftpcCreERT2 mice. The progeny was treated with tamoxifen and then challenged with S. pneumoniae. We found increased alveolar injury, loss of AT1 cells and reduced the frequency of proliferating AT2 cells in ABX-treated newborn mice compared to ABX-free newborn mice post-challenge with S. pneumoniae. Reconstitution of intestinal commensal bacteria or treatment with recombinant IL-22 restored the numbers of proliferating AT2 cells, reduced the injury score, and improved survival in ABX-treated newborn mice. Organoids derived ABX-exposed newborns demonstrated reduced growth and diminished AT1 differentiation. Using a developmentally appropriate and clinically relevant model, we report that intestinal commensal bacteria promote AT2 self-renewal and AT1 differentiation in an IL-22 dependent fashion, thus preparing the newborn to fight potentially fatal respiratory pathogens.

Moderate Intensity Continuous Training versus High Intensity Interval Training in Growth Restricted Mice to Improve Cardiac Function: A Pilot Study

IntroductionGrowth‐restriction during postnatal development has been linked to increased cardiovascular disease risk in adulthood, with greater impairment seen in females. Growth‐restricted mice present with thinner left ventricle posterior and anterior walls, compromised diastolic function and reduced stroke volume and cardiac output. Regular aerobic exercise training can promote cardiovascular health and well‐being, with recent evidence suggesting high intensity interval training may be more cardio protective as compared to moderate intensity continuous training. The purpose of this investigation was to determine if high intensity interval training (HIIT) promoted cardiac health in postnatally growth‐restricted female mice as compared to traditional moderate intensity continuous training (MICT).MethodsTo induce postnatal growth‐restriction, FVB mouse dams were fed either a 20% protein control diet or an 8% low‐protein isocaloric diet beginning 2 weeks before mating. Only pups born to control‐fed dams were used and cross‐fostered to either a low‐protein fed dam to induce growth‐restriction (PUN) or a different control fed dam (CON). On postnatal (PN) day 21 all pups were weaned and fed a control diet. At PN33 mice were allocated to MICT (PUN n=4, CON n=3), HIIT (PUN n= 4, CON n= 3) or a corresponding sedentary group (MICT: sedentary PUN n= 5, sedentary CON n=4; or HIIT: sedentary PUN n= 5, sedentary CON n=4). The MICT protocol was defined as treadmill running 3 days/week for 12 weeks at 17 m/min at −16 degree decline for 28 minutes and the HIIT protocol was treadmill running 5 days/week for 8 weeks with alternating intervals of 8 mins at 85% and 2 mins at 55% of maximum workload for 60 minutes. At PN 128 (MICT) and PN 98 (HIIT) echocardiography and Doppler blood flow was utilized to measure cardiac structure and function under 1% isoflurane anesthesia. Statistical analysis was performed using GraphPad Prism 8, utilizing two‐way ANOVAs with an alpha level of .05 set a priori and if significant Tukey’s post hoc for multiple comparisons was conducted.ResultsSedentary PUN groups exhibited cardiac dysfunction as evident by reduced left ventricle (LV) area during systole (p=.0290), LV diameter during diastole (p=.0156) and systole (p=.0003) and LV volume during systole (p=.0191). Systolic function was compromised in the PUN sedentary group by impaired myocardial performance index (MPI) (p=.0049), ejection fraction (EF) (p=.0023), aortic ejection time (AET) (p=.0345) and fractional shortening (FS) (p=.0111). Diastolic impairment manifested as reductions in isovolumic relaxation time (IVRT) (p=.0102) and mitral valve deceleration time (MVDT) (p=&lt;.0001) in the PUN sedentary group. Both MICT and HIIT were able to reverse impairments as no significant differences were noted between exercised PUN groups and their CON counterparts.ConclusionMICT and HIIT both reversed the cardiac impairments caused by growth‐restriction. Impairments caused by growth‐restriction can be mitigated with exercise training. Importantly, exercise professionals have flexibility in prescribing exercise as both MICT and HIIT were shown to be effective.

Combined Maternal Exposure to Cypermethrin and Stress Affect Embryonic Brain and Placental Outcomes in Mice.

Prenatal exposure to cypermethrin is a risk factor for adverse neurodevelopmental outcomes in children. In addition, maternal psychological stress during pregnancy has significant effects on fetal neurodevelopment and may influence end-stage toxicity to offspring by altering maternal xenobiotic metabolism. As such, this study examined effects of maternal exposure to alpha-cypermethrin and stress, alone and in combination, on offspring development, with a focus on fetal neurotoxicity. CD1 mouse dams were administered 10 mg/kg alpha-cypermethrin or corn oil vehicle via oral gavage from embryonic day 11 (E11) to E14. In addition, dams from each treatment were subjected to a standard model of restraint stress from E12 to E14. Cypermethrin treatment impaired fetal growth, reduced fetal forebrain volume, and increased ventral forebrain proliferative zone volume, the latter effects driven by combined exposure with stress. Cypermethrin also impaired migration of GABAergic progenitors, with different transcriptional changes alone and in combination with stress. Stress and cypermethrin also interacted in effects on embryonic microglia morphology. In addition, levels of cypermethrin were elevated in the serum of stressed dams, which was accompanied by interacting effects of cypermethrin and stress on hepatic expression of cytochrome P450 enzymes. Levels of cypermethrin in amniotic fluid were below the limit of quantification, suggesting minimal transfer to fetal circulation. Despite this, cypermethrin increased placental malondialdehyde levels and increased placental expression of genes responsive to oxidative stress, effects significantly modified by stress exposure. These findings suggest a role for interaction between maternal exposures to cypermethrin and stress on offspring neurodevelopment, involving indirect mechanisms in the placenta and maternal liver.

Enduring consequences of perinatal fentanyl exposure in mice.

Opioid use by pregnant women is an understudied consequence associated with the opioid epidemic, resulting in a rise in the incidence of neonatal opioid withdrawal syndrome (NOWS) and lifelong neurobehavioral deficits that result from perinatal opioid exposure. There are few preclinical models that accurately recapitulate human perinatal drug exposure and few focus on fentanyl, a potent synthetic opioid that is a leading driver of the opioid epidemic. To investigate the consequences of perinatal opioid exposure, we administered fentanyl to mouse dams in their drinking water throughout gestation and until litters were weaned at postnatal day (PD) 21. Fentanyl-exposed dams delivered smaller litters and had higher litter mortality rates compared with controls. Metrics of maternal care behavior were not affected by the treatment, nor were there differences in dams' weight or liquid consumption throughout gestation and 21 days postpartum. Twenty-four hours after weaning and drug cessation, perinatal fentanyl-exposed mice exhibited signs of spontaneous somatic withdrawal behavior and sex-specific weight fluctuations that normalized in adulthood. At adolescence (PD 35), they displayed elevated anxiety-like behaviors and decreased grooming, assayed in the elevated plus maze and sucrose splash tests. Finally, by adulthood (PD 55), they displayed impaired performance in a two-tone auditory discrimination task. Collectively, our findings suggest that perinatal fentanyl-exposed mice exhibit somatic withdrawal behavior and change into early adulthood reminiscent of humans born with NOWS.

Lactational metformin exposure programs offspring white adipose tissue glucose homeostasis and resilience to metabolic stress in a sex-dependent manner.

We previously demonstrated that exposing mouse dams to metformin during gestation results in increased beta-cell mass at birth and increased beta-cell insulin secretion in adult male offspring. Given these favorable changes after a gestational maternal metformin exposure, we wanted to understand the long-term metabolic impact on offspring after exposing dams to metformin during the postnatal window. The newborn period provides a feasible clinical window for intervention and is important for beta-cell proliferation and metabolic tissue development. Using a C57BL/6 model, we administered metformin to dams from the day of birth to postnatal day 21. We monitored maternal health and offspring growth during the lactation window, as well as adult glucose homeostasis through in vivo testing. At necropsy we assessed pancreas and adipocyte morphology using histological and immunofluorescent staining techniques. We found that metformin exposure programmed male and female offspring to be leaner with a higher proportion of small adipocytes in the gonadal white adipose tissue (GWAT). Male, but not female, offspring had an improvement in glucose tolerance as young adults concordant with a mild increase in insulin secretion in response to glucose in vivo. These data demonstrate long-term metabolic programming of offspring associated with maternal exposure to metformin during lactation.

A high-throughput platform for detailed lipidomic analysis of a range of mouse and human tissues

Lipidomics is of increasing interest in studies of biological systems. However, high-throughput data collection and processing remains non-trivial, making assessment of phenotypes difficult. We describe a platform for surveying the lipid fraction for a range of tissues. These techniques are demonstrated on a set of seven different tissues (serum, brain, heart, kidney, adipose, liver, and vastus lateralis muscle) from post-weaning mouse dams that were either obese (> 12 g fat mass) or lean (<5 g fat mass). This showed that the lipid metabolism in some tissues is affected more by obesity than others. Analysis of human serum (healthy non-pregnant women and pregnant women at 28 weeks’ gestation) showed that the abundance of several phospholipids differed between groups. Human placenta from mothers with high and low BMI showed that lean placentae contain less polyunsaturated lipid. This platform offers a way to map lipid metabolism with immediate application in metabolic research and elsewhere.Graphical abstract

Maternal ω3 docosapentaenoic acid inhibits infant allergic dermatitis through TRAIL-expressing plasmacytoid dendritic cells in mice.

BackgroundMaternal dietary exposures are considered to influence the development of infant allergies through changes in the composition of breast milk. Cohort studies have shown that ω3 polyunsaturated fatty acids (PUFAs) in breast milk may have a beneficial effect on the preventing of allergies in infants; however, the underlying mechanisms remain to be investigated. We investigated how the maternal intake of dietary ω3 PUFAs affects fatty acid profiles in the breast milk and their pups and reduced the incidence of allergic diseases in the pups.MethodsContact hypersensitivity (CHS) induced by 2,4‐dinitrofluorobenzene (DNFB) and fluorescein isothiocyanate was applied to the skin in pups reared by mother maintained with diets mainly containing ω3 or ω6 PUFAs. Skin inflammation, immune cell populations, and expression levels of immunomodulatory molecules in pups and/or human cell line were investigated by using flow cytometric, immunohistologic, and quantitative RT‐PCR analyses. ω3 PUFA metabolites in breast milk and infant's serum were evaluated by lipidomics analysis using LC‐MS/MS.ResultsWe show that maternal intake of linseed oil, containing abundant ω3 α‐linolenic acid, resulted in the increased levels of ω3 docosapentaenoic acid (DPA) and its 14‐lipoxygenation products in the breast milk of mouse dams; these metabolites increased the expression of TNF‐related apoptosis‐inducing ligand (TRAIL) on plasmacytoid dendritic cells (pDCs) in their pups and thus inhibited infant CHS. Indeed, the administration of DPA‐derived 14‐lipoxygenation products to mouse pups ameliorated their DNFB CHS.ConclusionThese findings suggest that an inhibitory mechanism in infant skin allergy is induced through maternal metabolism of dietary ω3 PUFAs in mice.

Bisphenol A and bisphenol S disruptions of the mouse placenta and potential effects on the placenta–brain axis

Placental trophoblast cells are potentially at risk from circulating endocrine-disrupting chemicals, such as bisphenol A (BPA). To understand how BPA and the reputedly more inert bisphenol S (BPS) affect the placenta, C57BL6J mouse dams were fed 200 μg/kg body weight BPA or BPS daily for 2 wk and then bred. They continued to receive these chemicals until embryonic day 12.5, whereupon placental samples were collected and compared with unexposed controls. BPA and BPS altered the expression of an identical set of 13 genes. Both exposures led to a decrease in the area occupied by spongiotrophoblast relative to trophoblast giant cells (GCs) within the junctional zone, markedly reduced placental serotonin (5-HT) concentrations, and lowered 5-HT GC immunoreactivity. Concentrations of dopamine and 5-hydroxyindoleacetic acid, the main metabolite of serotonin, were increased. GC dopamine immunoreactivity was increased in BPA- and BPS-exposed placentas. A strong positive correlation between 5-HT+ GCs and reductions in spongiotrophoblast to GC area suggests that this neurotransmitter is essential for maintaining cells within the junctional zone. In contrast, a negative correlation existed between dopamine+ GCs and reductions in spongiotrophoblast to GC area ratio. These outcomes lead to the following conclusions. First, BPS exposure causes almost identical placental effects as BPA. Second, a major target of BPA/BPS is either spongiotrophoblast or GCs within the junctional zone. Third, imbalances in neurotransmitter-positive GCs and an observed decrease in docosahexaenoic acid and estradiol, also occurring in response to BPA/BPS exposure, likely affect the placental-brain axis of the developing mouse fetus.

Exposure to the UV Filter Octyl Methoxy Cinnamate in the Postnatal Period Induces Thyroid Dysregulation and Perturbs the Immune System of Mice.

Evidence demonstrates the bidirectional communication and regulation between the neuroendocrine and immune systems. Thyroid hormones play key roles in nervous system development and can exert influence on various immune cells contributing to pathophysiological conditions. Octyl methoxycinnamate (OMC) is one of the most commonly used UV filters, and in vitro and in vivo studies have found thyroid disrupting effects. The present study assessed whether OMC administration in mice dams during the lactational period can cause thyroid disruption and generate immunologic alterations in the offspring. Indirect exposure to the OMC (1,000 mg/kg) in the lactational period affected neurodevelopment parameters, such as delayed eye-opening and weight gain in mice of both sexes, and these alterations are corroborated by the decrease in the T4 levels present in the pups' blood. No significant changes were observed in the thymus of these pups, but the number of lymphocytes increased in the spleen of the animals exposed to OMC, similar to the animals treated with propyl-thiouracil (PTU), a well-known thyroid disruptor. OMC modulated the percentage of leukocyte populations in peripheral blood, and the number of circulating polymorphonuclear cells increased two-fold. In vitro, OMC exhibited an inhibitory effect on splenocyte proliferation and IL-2 production induced by anti-CD3 antibody; however, this effect was reversed with the addition of T4 in the cell culture. In summary, the results of the present study demonstrate the influence of OMC on thyroid dysregulation and its impact on the modulation of the immune system in mice pups.

Prenatal Choline Supplementation during High-Fat Feeding Improves Long-Term Blood Glucose Control in Male Mouse Offspring.

Maternal obesity increases the risk of metabolic dysregulation in rodent offspring, especially when offspring are exposed to a high-fat (HF), obesogenic diet later in life. We previously demonstrated that maternal choline supplementation (MCS) in HF-fed mouse dams during gestation prevents fetal overgrowth and excess adiposity. In this study, we examined the long-term metabolic influence of MCS. C57BL/6J mice were fed a HF diet with or without choline supplementation prior to and during gestation. After weaning, their pups were exposed to either a HF or control diet for 6 weeks before measurements. Prenatal and post-weaning dietary treatments led to sexually dimorphic responses. In male offspring, while post-weaning HF led to impaired fasting glucose and worse glucose tolerance (p < 0.05), MCS in HF dams (HFCS) attenuated these changes. HFCS (versus maternal normal fat control) appeared to improve metabolic functioning of visceral adipose tissue during post-weaning HF feeding, preventing the elevation in leptin and increasing (p < 0.05) mRNA expression of insulin receptor substrate 1 (Irs1) that promotes peripheral insulin signaling in male offspring. In contrast, MCS had minimal effects on metabolic outcomes of female offspring. In conclusion, MCS during HF feeding in mice improves long-term blood glucose homeostasis in male offspring when they are faced with a postnatal obesogenic environment.

The effects of exposure to fluoxetine during lactation on testicular tissue and sperm parameters in mice offspring.

Fluoxetine is a selective serotonin reuptake inhibitor is commonly prescribed to treat maternal depression in pregnancy and lactation. This study aimed to investigate the effects of maternal exposure to fluoxetine via lactation on testicular tissue, sperm parameters including count, motility, viability, and normal morphology and testicular oxidative stress status in male mice offspring. Ten mice dams were divided into control and experimental groups. The control group received water and the experimental group received fluoxetine (20.00 mg kg-1) by gavage daily from postnatal days of 0-21. Histology of testis, sperm parameters and oxidative stress in the testicular tissue were analyzed at 80 days after birth in their male offspring (n = 8). Significant reductions in the body and testes weights were observed in animals exposed to fluoxetine. Additionally, fluoxetine exposure significantly reduced all sperm parameters, tubular diameter and epithelial height of the seminiferous tubules as well as Leydig cells number. Significant increases in the testicular malondialdehyde levels and percentage of sperm with chromatin/DNA damage were observed in mice exposed to fluoxetine compared to control. These findings suggest that maternal exposure to fluoxetine during lactation in mice has a negative effect on the testicular tissue of their offspring and impairs the spermatogenesis process which in turn can induce infertility.

1211 Beta-hydroxy-beta-methylbutyrate (HMB) supplementation to mouse dams in gestation does not affect birth weight variation or growth of offspring

Abstract The objective of this study was to determine if supplementing diets with β-hydroxy-β-methylbutyrate (HMB) calcium salt for mouse dams throughout gestation would improve pup birth weight uniformity and growth performance of offspring. Dams were assigned to one of 4 treatments as follows: control (CON; n = 6), Low Level HMB (LL; 3.5 mg/g diet; n = 7), High Level HMB (HL; 35 mg/g diet; n = 8), and Low Level Pulse fed from gestational days 6 to 10 (PUL; 3.5 mg/g diet; n = 7). Supplementation began at mating and continued until birth. Dams gave birth and lactated for 28 days. Offspring were reared until 8 weeks of age. All mice had ad libitum access to a corn-soybean meal diet, with HMB supplementation provided only to dams during gestation. Supplementation of HMB had no effects on overall gestation and lactation performance of mouse dams. Dietary treatment during gestation did not affect total number of pups born per litter, birth weight of pups, or number weaned. Within litter variation, expressed as standard deviation and coefficient of variation, was not different among treatments for birth weight or weaning weight. Range of body weights within litter at birth, weaning, and 8 weeks of age were not affected by HMB supplementation. Overall, offspring growth performance was similar among treatments. However, body weight at 5 and 8 weeks of age was lower for offspring from the HL dams compared to offspring from LL dams (P &amp;lt; 0.05). Body composition of offspring at 5 and 8 weeks of age was similar regardless of HMB supplementation in dam diets during gestation. In conclusion, dietary HMB supplementation of mouse dams during gestation had no effect on birth weight of offspring, variation in birth weight, or growth performance of offspring.

Brain-wide genetic mapping identifies the indusium griseum as a prenatal target of pharmacologically unrelated psychostimulants

Psychostimulant use is an ever-increasing socioeconomic burden, including a dramatic rise during pregnancy. Nevertheless, brain-wide effects of psychostimulant exposure are incompletely understood. Here, we performed Fos-CreERT2-based activity mapping, correlated for pregnant mouse dams and their fetuses with amphetamine, nicotine, and caffeine applied acutely during midgestation. While light-sheet microscopy-assisted intact tissue imaging revealed drug- and age-specific neuronal activation, the indusium griseum (IG) appeared indiscriminately affected. By using GAD67gfp/+ mice we subdivided the IG into a dorsolateral domain populated by γ-aminobutyric acidergic interneurons and a ventromedial segment containing glutamatergic neurons, many showing drug-induced activation and sequentially expressing Pou3f3/Brn1 and secretagogin (Scgn) during differentiation. We then combined Patch-seq and circuit mapping to show that the ventromedial IG is a quasi-continuum of glutamatergic neurons (IG-Vglut1+) reminiscent of dentate granule cells in both rodents and humans, whose dendrites emanate perpendicularly toward while their axons course parallel with the superior longitudinal fissure. IG-Vglut1+ neurons receive VGLUT1+ and VGLUT2+ excitatory afferents that topologically segregate along their somatodendritic axis. In turn, their efferents terminate in the olfactory bulb, thus being integral to a multisynaptic circuit that could feed information antiparallel to the olfactory-cortical pathway. In IG-Vglut1+ neurons, prenatal psychostimulant exposure delayed the onset of Scgn expression. Genetic ablation of Scgn was then found to sensitize adult mice toward methamphetamine-induced epilepsy. Overall, our study identifies brain-wide targets of the most common psychostimulants, among which Scgn+/Vglut1+ neurons of the IG link limbic and olfactory circuits.