During the perinatal period, the mother’s diet and behavior influence the course of development of the offspring. Several studies indicated that maternal depression and obesity increase the risk of developing psychological and neurological diseases in children.
Scientists recently reviewed mechanisms associated with the maternal microbiome, breast milk composition, maternal and placental metabolites, altered maternal care, and inflammation, which influence brain development in offspring. This review was published in metabolites.
Obesity during pregnancy
Obesity is a worldwide metabolic disorder. However, this disorder can be prevented through lifestyle modification. In 2017, the Royal College of Obstetricians and Gynecologists discovered that around a quarter of pregnant women in the UK are obese. A similar rate of obesity has been reported across continental Europe.
Excessive gestational weight gain (GWG) is another common condition during pregnancy among women residing in western countries, such as the USA, Australia, and the UK. Women with high BMI values before pregnancy are at significantly increased risk of excessive GWG and postpartum weight retention. Many pregnant women gain weight due to high amounts of fat in their diet during pregnancy.
Recently, researchers have investigated how maternal diet and obesity affect the behavior of mothers and children. These studies showed that mental illnesses can be transmitted to children through the poor health of the mother during pregnancy and in the early stage of the newborn’s life.
Maternal obesity has been directly linked to attention deficit hyperactivity disorder (ADHD), regardless of birth weight. Obesity before pregnancy has been associated with difficulties with emotional strength in children. In addition, many of these children suffer from many behavioral problems, such as dissociative disorders, obsessive-compulsive disorder, and eating disorders.
Scientists have identified some factors that influence the neurodevelopment and emotional behavior of children. Animal studies using the offspring of rodents and non-human primates (NHP) have indicated how the high-fat diet of prenatal mothers affects the brain and behavior of the offspring. that in vivo A mouse model study revealed that the expression of TLR4 and CD11b, two markers of central nervous system (CNS)-microglia, were significantly upregulated in the juvenile offspring of obese mice fed a diet high in saturated fat.
Under normal conditions, TLR4 is activated for strong pro-inflammatory responses to bacterial endotoxins. TLR4 activation mediates central inflammatory signaling and modulates brain metabolism. Compared to a healthy control group, the baseline level of IL-1β protein was found to be significantly increased in the hippocampus and periphery (liver) of young adult offspring of dams fed a high-fat diet (HFD). These changes in offspring exposed to HFD have been associated with increased anxiety. In addition, consumption of a maternal HFD (mHFD) during pregnancy was found to increase anxiety-like behavior in female offspring of NHP. Furthermore, disturbances in the serotonergic system have been observed with a decrease in cerebrospinal fluid levels of serotonin.
Ethical studies have indicated that infant primates raised without maternal care develop severe social deficits and become attached to inanimate objects that provide a sense of comfort. During the early postpartum period, maternal care or neglect plays an important role in the child’s neurodevelopment. Clinical studies have also demonstrated the relationship between childhood maltreatment and altered neurobiology and behavior.
Preclinical studies have indicated some mechanisms mediating the effect of maternal neglect. The embryonic programming theory entails exposure to significant neglect or other stressors during the early postnatal period that affect the development of a child’s brain. Not much evidence has been documented regarding the effect of maternal diet-induced obesity on offspring behavior.
Maternal obesity may affect the brain and behavior of the offspring due to changes in the gut microbiome of the mother and the offspring. Gut dysbacteriosis caused by diet or antimicrobial treatment affects the offspring’s microbiome, which in turn affects the offspring’s brain development and behaviour. Microbial metabolites contribute to fetal nutrition, which is important for the origins of immunity and neurodevelopment.
More research is needed to understand how changes induced by obesity in the mother’s microbiome affect the neurological development and behavior of the offspring. Most obese mothers have a deficiency bifidobacteria spp. or lactobacillus spp, which reduces beneficial metabolites.
Obesity is an inflammatory condition associated with a persistent increase in circulating pro-inflammatory cytokines (for example, IL-6). Several studies have indicated that obesity during pregnancy exacerbates inflammation that affects fetal development.
Breast milk is very dynamic in composition. Breastmilk becomes fully mature four to six weeks after birth. Contains essential nutrients and growth factors for infant health and development. The mother’s BMI influences the overall composition of breast milk, which is associated with the psychopathology of the offspring. Animal studies using mice have shown that maternal obesity during lactation can influence metabolic inflammation and precocious puberty development in offspring.
Appropriate dietary changes to improve metabolic health may be beneficial for women before, during and after pregnancy. In addition, modulation of the maternal microbiome could be beneficial in mitigating the risks of metabolic and/or mood disorders in the neonate. In the future, a personalized probiotic treatment could be designed, which would be beneficial for both mother and child.