Long-term impact of maternal obesity on the gliovascular unit and ephrin signaling in the hippocampus of adult offspring

BACKGROUND

Children born to obese mothers are at increased risk of developing mood disorders and cognitive impairment. Experimental studies have reported structural changes in the brain such as the gliovascular unit as well as activation of neuroinflammatory cells as a part of neuroinflammation processing in aged offspring of obese mothers. However, the molecular mechanisms linking maternal obesity to poor neurodevelopmental outcomes are not well established. The ephrin system plays a major role in a variety of cellular processes including cell-cell interaction, synaptic plasticity, and long-term potentiation. Therefore, in this study we determined the impact of maternal obesity in pregnancy on cortical, hippocampal development, vasculature and ephrin-A3/EphA4-signaling, in the adult offspring in mice.

METHODS

Maternal obesity was induced in mice by a high fat/high sugar Western type of diet (HF/HS). We collected brain tissue (prefrontal cortex and hippocampus) from 6-month-old offspring of obese and lean (control) dams. Hippocampal volume, cortical thickness, myelination of white matter, density of astrocytes and microglia in relation to their activity were analyzed using 3-D stereological quantification. mRNA expression of ephrin-A3, EphA4 and synaptic markers were measured by qPCR in the brain tissue. Moreover, expression of gap junction protein connexin-43, lipocalin-2, and vascular CD31/Aquaporin 4 were determined in the hippocampus by immunohistochemistry.

RESULTS

Volume of hippocampus and cortical thickness were significantly smaller, and myelination impaired, while mRNA levels of hippocampal EphA4 and post-synaptic density (PSD) 95 were significantly lower in the hippocampus in the offspring of obese dams as compared to offspring of controls. Further analysis of the hippocampal gliovascular unit indicated higher coverage of capillaries by astrocytic end-feet, expression of connexin-43 and lipocalin-2 in endothelial cells in the offspring of obese dams. In addition, offspring of obese dams demonstrated activation of microglia together with higher density of cells, while astrocyte cell density was lower.

CONCLUSION

Maternal obesity affects brain size, impairs myelination, disrupts the hippocampal gliovascular unit and decreases the mRNA expression of EphA4 and PSD-95 in the hippocampus of adult offspring. These results indicate that the vasculature-glia cross-talk may be an important mediator of altered synaptic plasticity, which could be a link between maternal obesity and neurodevelopmental/neuropsychiatric disorders in the offspring.

Obesity in pregnancy is associated with macrophage influx and an upregulated GRO-alpha and IL-6 expression in the decidua

About one third of all reproductive-aged women are affected by obesity. Maternal obesity is linked to an adverse outcome for both mother and child. The expression of the pro-inflammatory IL-6 and GRO-alpha as well as the infiltration of macrophages in the placenta of obese, non-diabetic pregnancies was examined by immunohistochemistry in comparison to the placenta of normal weight women. In obese pregnancies the influx of macrophages was significantly increased (p = 0.012). The protein expression of IL-6 and GRO-alpha was significantly elevated (p = 0.036 and p < 0.001, respectively) in the decidua of adipose females.

Change in timing of induction protocol in nulliparous women to optimise timing of birth: results from a single centre study

BACKGROUND

Induction of labour (IOL) is a common obstetric intervention. When planning IOL, especially in women at risk for complications at delivery, the aim should be for delivery to occur when senior staff are available to optimise safe care.

METHODS

A change in timing of IOL protocol at our institution was introduced in November 2018 aiming to increase births occurring "in-hours" defined as 08:00 to 20:00 h. This retrospective cohort study compares the odds of "in-hours" birth before and after the intervention and the association on birth outcomes. The study compared outcomes during the new IOL pathway period to a historical birth cohort from January to December 2017. Inclusion criteria were nulliparous women undergoing planned IOL at term with a cephalic singleton pregnancy. Logistic regression was used to compare odds of in-hours birth for the 2 periods with adjustment for maternal age at delivery, gestation, more than 2 cervical ripening agents required, undergoing IOL for post-dates pregnancy, mode of birth, whether or not IOL proceeded according to planned protocol and missing values using multiple imputation.

RESULTS

The rate of deliveries occurring in-hours were higher following the intervention; n = 118/285 (45.6%) pre-intervention versus n = 251/470 (53.4%) post-intervention; adjusted OR = 1.47, 95% CI = 1.07-2.01, p = 0.02). The percentage of caesarean sections (CS) occurring in-hours was significantly lower in the pre-intervention group n = 71/153 (28.3%) compared with the post intervention group = 35/132(46.4%) (p < 0.001)). The rate of CS was higher in the pre intervention n = 132/285(46.3%) compared with the post intervention group n = 153/470 (32.4%)).

CONCLUSIONS

The change in induction procedures was associated with a significantly higher rate of births occurring in-hours and a lower rate of overall of CS. This policy change led to a better pattern of timing of birth for nulliparous women undergoing IOL.

Effect of high-fat diet for rats at different stages on glucose and lipid metabolism in offspring and related mechanisms

OBJECTIVES

To study the effect of high-fat diet for maternal Sprague-Dawley rats at different stages on glucose and lipid metabolism in offspring and related mechanisms.

METHODS

According to the diet before pregnancy and during pregnancy and lactation, maternal rats were randomly divided into four groups (n=9 each): CC (control diet before pregnancy and during pregnancy and lactation), HC (high-fat diet before pregnancy and control diet during pregnancy and lactation), CH (control diet before pregnancy and high-fat diet during pregnancy and lactation), and HH (high-fat diet before pregnancy and during pregnancy and lactation), and all offspring rats were given control diet after weaning. The body weight of maternal rats was recorded before and during pregnancy. Male offspring rats were selected from each group at the juvenile stage (3-week old) and the adult stage (12-week old) to measure the levels of fasting blood glucose (FBG) and fasting insulin (FINS) and the levels of triglyceride (TG) and total cholesterol (TC) in the liver. Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) index was calculated, and the area under the curve (AUC) was calculated for glucose tolerance test (GTT) and insulin tolerance test (ITT). Lipid deposition in the liver was observed, and the mRNA and protein expression levels of the key genes in glucose and lipid metabolism (IR, IRS, and AKT), FASN, SREBP1c, and PPARα in the liver were also measured.

RESULTS

Compared with the control diet groups (CC and CH groups), the groups with high-fat diet before pregnancy (HC and HH groups) had a significant increase in body weight (P<0.001). Compared with the CC group, the HC, CH, and HH groups had a significantly greater increase in body weight (P<0.001). Compared with the CC group, the HC, CH, and HH groups had significant increases in body weight, the levels of TG and TC in the liver, and the mRNA and protein expression levels of FASN, SREBP1c, and PPARα in the offspring rats at week 3 after birth (P<0.05), as well as a significant increase in lipid deposition in the liver, with the most significant increase of the parameters in the HH group. Compared with the CC group, the HH group had significant increases in the levels of FBG and FINS, HOMA-IR index, GTT-AUC, ITT-AUC, and the protein expression level of p-IRS in the liver and significant reductions in the mRNA and protein expression levels of IR and IRS in the liver in the offspring rats at week 3 after birth (P<0.05). Compared with the CC group, the HC, CH, and HH groups had significant increases in body weight, the levels of FBG and FINS, HOMA-IR index, GTT-AUC, ITT-AUC, the levels of TG and TC in the liver, protein expression level of p-IRS in the liver, and the mRNA and protein expression levels of FASN, SREBP1c, and PPARα in the offspring rats at week 12 after birth (P<0.05), as well as a significant increase in lipid deposition in the liver, with the most increase of the parameters in the HH group. Compared with the CC group, the HC, CH, and HH groups had significant reductions in the mRNA expression levels of IR, IRS, and AKT and the protein expression levels of IR, IRS, and p-AKT in the offspring rats at week 12 after birth (P<0.05). There were no significant differences in the levels of glucose and lipid metabolism between the HC and CH groups at various stages (P>0.05).

CONCLUSIONS

High-fat diet for rats at different stages before and after pregnancy has different effects on glucose and lipid metabolism of offspring rats, and high-fat diet before pregnancy and during pregnancy and lactation has the greatest effect. The effect of high-fat diet on glucose and lipid metabolism of offspring rats is considered associated with the changes in the expression of genes involved in glucose and lipid metabolism.

Relationship of maternal obesity and vitamin D concentrations with fetal growth in early pregnancy

Purpose

To evaluate the effects of the association between first trimester vitamin D (VitD) concentrations and increased prepregnancy body mass index (BMI) on early fetal growth restriction (FGR).

Methods

This retrospective cohort study included 15,651 women with singleton pregnancy who delivered at the International Peace Maternity and Child Health Hospital between January 2015 and November 2016. Women were classified in two groups based on their serum 25(OH)D vitamin levels status: VitD sufficient (SUFF) group and VitD insufficient or deficient (INSUFF/DEF). The cut-off point for VitD concentration was 50.00 nmol/L. Comparisons were made between women with normal prepregnancy body weight (BMI 18.5–23.9 kg/m²) and overweight and obese (OWO) women (BMI > 24.0 kg/m²). Early FGR was defined as first-trimester gestational age-adjusted crown-rump length (CRL) in the lowest 20th centile of the population. Multivariate logistic regression was used to evaluate the association between maternal serum 25(OH)D levels and prepregnancy BMI with first trimester CRL and early FGR.

Results

In VitD INSUFF/DEF group, the first trimester CRL was decreased (P = 0.005), and the risk of early FGR was increased by 13% (95% CI 1.04–1.24, P = 0.004) compared to the VitD SUFF group. In OWO group, the first trimester CRL was also significantly decreased (P < 0.0001), and the risk of early FGR was significantly increased by 58% (95% CI 1.40–1.78, P < 0.001) compared with normal weight group. Furthermore, there was a significant combined effect of maternal VitD concentrations and OWO on CRL (P for interaction = 0.02) and the risk of early FGR (P for interaction = 0.07).

Conclusion

Sufficient first trimester serum 25(OH)D concentration was a protective factor for early fetal growth, especially among OWO mothers. Chinese Clinical Trial Registry (Registration number: ChiCTR1900027447 with date of registration on November 13, 2019-retrospectively registered).

Supplementary Information

The online version contains supplementary material available at 10.1007/s00394-021-02695-w.

Women's recall of health care provider counselling on gestational weight gain (GWG): a prospective, population-based study

BACKGROUND

Prenatal care has been validated to provide medical and educational counselling intended to reduce the risk of adverse pregnancy conditions and improve the maternal and fetal outcomes. Prenatal targeted information regarding nutrition, lifestyle, and weight gain is predictive of meeting Institute of Medicine (IOM) 2009 gestational weight gain (GWG) guidelines. There is limited information about women's experiences with these prenatal counselling domains, particularly in women who do not meet GWG recommendations. The objective of this study was to evaluate the impact of women's recall of prenatal counselling and its effect on meeting their GWG within guidelines in a prospective, community-based pregnancy cohort.

METHODS

A sample of 2909 women with singleton pregnancies was drawn from the prospective community-based pregnancy cohort All Our Families from Alberta, Canada. Women were stratified into three GWG groups, adequate, inadequate, and excessive GWG, based on pre-pregnancy BMI and the adherence to the Institute of Medicine weight gain in pregnancy guidelines. At less than 25 and 34 to 36 weeks' gestation, maternal socio-demographic information and women's recall of prenatal counselling experiences was collected through self-administered questionnaires. Multivariate logistic regression analyses tested GWG strata impact on women's recall of the prenatal counselling advice in eight domains of nutrition, lifestyle, and weight management during pregnancy.

RESULTS

Adequate GWG was reached by 35.9% of women, 46.5% gained excessive and 17.6% gained inadequate weight. Women who were overweight and obese prior to pregnancy were more likely to gain excessive weight than women who were normal weight (OR 3.3, 95% CI 2.6-4.1; and OR 2.9, 95% CI 2.1-3.9, respectively). Most women reported having no difficulties in finding prenatal care, felt comfortable with their health care provider and were satisfied with the answers received. There was no difference in the recall of prenatal advice received in any of the eight domains of prenatal counselling assessed among women with appropriate and non-optimal GWG.

CONCLUSION

Women with adequate and non-optimal GWG received comparable prenatal counselling on nutrition, weight gain, and lifestyle modifications. There remain missed opportunities in targeting prenatal counselling advice to women at risk for suboptimal or excessive GWG.

Recall of Prenatal Counselling Among Obese and Overweight Women from a Canadian Population: A Population Based Study

Objective The objective of this study was to evaluate the recall of prenatal counselling received among overweight and obese women in primary care settings. Methods A sample of 1996 women with singleton, term deliveries and pre-pregnancy BMI >18.5 kg/m² were identified from the All Our Babies pregnancy cohort. Information on socio-demographic characteristics and women's experiences with prenatal counselling on nutrition, vitamin and mineral supplements, exercise, weight gain, employment, alcohol and drug use, and smoking during pregnancy were collected through questionnaires administered at <25 weeks and 34-36 weeks gestation. Multivariable logistic regression analyses explored the associations between pre-pregnancy BMI and the domains of prenatal counselling, controlling for confounders. Results Women reported high levels of comfort asking questions and satisfaction with their health care provider. Women reported getting information about nutrition (69.3%), weight gain (67.8%), exercise (64.4%), vitamins and minerals supplementation (86.1%). Obese women (211, 10.6%) were more likely than normal weight women (1313, 65.8%) to be Caucasian (p = 0.004), less educated (p = 0.001), and to have been born or lived in Canada for at least 5 years (p = 0.01). There was no difference in the prenatal advice received on nutrition, weight gain and exercise in pregnancy between obese, overweight, and normal weight women. Conclusions for Practice Pre-pregnancy BMI did not appear to influence the recall of prenatal counselling women receive in community health care centers. Given the importance of nutrition and weight gain during pregnancy, and guidelines for weight gain based on pre-pregnancy BMI, there are missed opportunities in knowledge exchange between women and providers in the prenatal period.

Maternal obesity and prenatal programming

Obesity is a significant and increasing public health concern in the United States and worldwide. Clinical and epidemiological evidence clearly shows that genetic and environmental factors contribute to the increased susceptibility of humans to obesity and its associated comorbidities; the interplay of these factors is explained by the concept of epigenetics. The impact of maternal obesity goes beyond the newborn period; fetal programming during the critical window of pregnancy, can have long term detrimental effects on the offspring as well as future generations. Emerging evidence is uncovering a link between the clinical and molecular findings in the offspring with epigenetic changes in the setting of maternal obesity. Research targeted towards reducing the transgenerational propagation and developmental programming of obesity is vital in reducing the increasing rates of disease.