Blockbuster study: mother’s gut microbiota disorders affect children’s neurodevelopment

Intestinal tract is an important organ of human body, responsible for digestion and absorption of nutrients. In addition, as the largest lymphoid tissue in the body, the intestine also has the function of endocrine and immune regulation. Intestinal epithelial cells are the barrier between the body and the external environment. The microorganisms in the gut are closely related to the metabolic function and immune function of the gut. < / P > < p > there are nearly 100 trillion bacteria in human intestinal tract, known as “the second genome of human body”. Under normal circumstances, these bacteria are in a dynamic equilibrium state of Microecology in the intestine, which plays a vital role in human health. When this balance tends to be disordered and gradually out of balance, it will cause disease or aggravate the original condition, and even lead to organ dysfunction or failure. < / P > < p > intestinal flora disorder can cause serious damage to our own health, but scientific research has found that the harm of intestinal flora disorder is not limited to this. Once the intestinal flora of pregnant women is out of balance, in addition to their own health is seriously threatened, the fetus in the belly will also be threatened! < / P > < p > on September 23, 2020, scientists from UCLA published a heavyweight study in a top magazine, which found that the defect of maternal intestinal flora can interfere with the axogenesis of embryonic thalamic cortical neurons, thus affecting the behavioral characteristics of tactile sensory neurons in offspring. < / P > < p > in order to know whether the mother’s intestinal flora affects the fetal brain development, the researchers first fed antibiotics to the pregnant rat mother, and from the pre pregnancy to the second trimester of pregnancy, the rat mother’s intestinal microorganisms were in a state of exhaustion. At 14.5 days of development, the expression of 333 genes in the brain changed, including many genes related to axogenesis. < / P > < p > since the disturbance of the mother’s intestinal flora will affect the neural development of the fetus, will this effect last until the offspring reach adulthood? When rat treasure grew into adult rats, the researchers tested their senses. In the experiment of pressure perception, compared with the normal mice, the rats born from the mothers with intestinal flora disorder had to exert more pressure before they knew to withdraw the pressed hind paw, indicating that their tactile sensation was impaired. < / P > < p > from the results of these experiments, it can be seen that in the process of pregnancy and embryonic development, the normal intestinal flora of the mother plays an important role in the brain axogenesis of mice, mediating the transmission of tactile sensation after birth and even adulthood. < / P > < p > so, how does the mother’s intestinal flora affect the fetal neural development? The metabolites of the intestinal flora of the mother rat enter the fetal rat body through the umbilical cord, and then enter the brain through the blood circulation, affecting the neural development of the fetal rat brain. < / P > < p > the researchers believe that this study suggests that we should pay attention to the health of mother’s intestinal flora during pregnancy, which may not only affect the health of mother, but also affect the development of offspring. < / P > < p > however, what’s more surprising is that the influence of the mother’s intestinal flora on the fetus is far beyond neural development, and many aspects of fetal growth and development are regulated by the mother’s intestinal flora. < / P > < p > on February 28, 2020, a research team in Japan published a paper in a top journal, which showed that the effect of intestinal flora on obesity can even be traced back to “maternal fetus”. < / P > < p > in this study, the scientists first showed a group of experimental comparison results: the two groups of mice stayed in the same environment and ate the same things from birth, but one group of mice immediately gained weight as soon as they ate a high-fat diet. As they grew older, they had higher body fat and blood lipids than their peers, and were more likely to have diabetes risk. < / P > < p > the “obesity prone constitution” of this group of mice was originally closely related to their mother’s intestinal flora. While they were still in their mother’s womb, the researchers kept pregnant rats in sterile conditions. As a result, the loss of mother’s intestinal flora makes it difficult for these mice to resist the obesity brought by high-fat diet after birth. < / P > < p > according to scientists’ understanding of the intestinal flora, one of their important functions is to help us degrade some indigestible nutrients, such as dietary fiber. In the process of digestion, intestinal bacteria produce a variety of metabolites to “feed back” us, such as short chain fatty acids. < / P > < p > the researchers examined pregnant rats and their fetuses, and found that in the absence of intestinal flora, the content of some short chain fatty acids in the plasma of pregnant rats decreased significantly. Moreover, several kinds of short chain fatty acids also decrease synchronously in fetal blood. < / P > < p > they concluded that these short chain fatty acids may be the key signals affecting the fetus, which are produced by the mother’s intestinal bacteria and transferred to the embryo through the mother’s blood. < / P > < p > the final research results show that the intestinal flora of pregnant mother has a long-term impact on the healthy development of the fetus in the future: when some metabolites of intestinal bacteria of the mother are insufficient, mice are easy to get fat after birth and develop metabolic disorders; dietary fiber supplementation during pregnancy can help children prevent related metabolic diseases. < / P > < p > on January 8, 2020, scientists from Harvard University in the United States published a paper in a top magazine, which confirmed that the mother’s intestinal flora is the source of neonatal immunity. < / P > < p > in the current study, researchers work with newborn mice that have been genetically engineered to lack B cells, which are antibody producing factories in the immune system. < / P > < p > other newborn mice were raised by their mothers with normal immune system. Mice exposed to their mothers’ protective antibodies were much more resistant to E.coli infection than mice not exposed to such antibodies, and their intestinal E.coli bacteria were 33 times less than those of newborn mice lacking maternal antibodies. < / P > < p > and where do these protective antibodies come from? It belongs to the family of Enterobacteriaceae. It exists in the intestines of mice and other mammals. < / P > < p > this means that even if the mother has not experienced infection before, the intestinal flora can provide immune protection, so that they can establish and pass on protective antibodies to their offspring. In addition, experiments have shown that antibodies enter the intestine and blood of newborns through Fc receptor, which is a molecular channel on the placenta and can help transport protective antibodies from the mother to the fetus. Up to now, it is known that the receptor can transfer antibody through placenta. In addition, experiments conducted in this new study show that the receptor also absorbs antibodies from milk and transfers them from the gut to the blood of newborn mice, thus ensuring broader systemic protection outside the gut. < / P > < p > for pregnant mothers, their biggest wish is for their babies to grow up healthily and do their best to protect them from the wind and rain. The latest top magazine studies have revealed the importance of mother’s intestinal flora for the health of the baby. Therefore, expectant mothers should pay attention to this. Proper supplementation of probiotics and dietary fiber can have great benefits! PARRENT&CHILDREN