Mothers having suffered an inflammation during pregnancy have children with changes in brain structure and subsequent changes in function. This was the conclusion of a recent study by a group of researchers from the Charité University Medicine Berlin in Germany and Oregon Health Sciences University.
Researchers looked at maternal plasma interleukin-6 concentrations during pregnancy. Interleukin-6 is produced at the site of inflammation, and it plays a role in acute inflammation. The concentrations were co-related with functional magnetic resonance imaging in neonates and the memory functions of the infants when they were 2 years old. The functional connectivity in the neonate brains could be modeled to relate to the maternal interleukin-6 concentrations.
Historically, viral infections during pregnancy have been considered benign. But with expanded understanding of the ways the maternal-fetal interface and fetal placenta relate to a mother's immune system, there are gains in how maternal immunological systems promote and protect fetal development. When the protection breaks down and the developing fetus is exposed to products of inflammation, there are consequences as the recent study demonstrated.
Interleukin-6 is an inflammation associated cytokine, and cytokines are involved in cell signaling. Another group looked at five cytokines: interleukin-6, interleukin1beta, interleukin-8, tumor necrosis factor alpha and interleukin-10 during the second and third trimesters of 1,366 women participating in the New England Family Study that ran from 1959 to 1966. The IQ, academic achievement and neuropsychological findings of the children were later measured when they were 7 years old.
The researchers found the children who had been exposed to higher levels of tumor necrosis factor alpha had lower IQs and higher dysfunction scores in visual motor status. Higher levels of interleukin-8 were associated with better scores with a "draw a person" test and better tactile finger recognition scores. The researchers concluded that the opposing impact of different cytokines suggest multiple effects from gestational inflammation across functional neurocognitive domains.
"This study shows in very clear terms how the immune system can impact offspring brain development and behavior. The study establishes a missing link between inflammation in pregnant women and the way the entire newborn brain is organized into networks," Damien Fair, Ph.D. one of the authors from Oregon Health Sciences University, told MedPage Today.
"Future work should focus on questions about how diet and other environmental factors interact to influence changes to the immune system before and after birth. These factors of our everyday lives are modifiable. It will be just as important as research that studies the subsequent effects of inflammation on brain function and cognition in newborns to determine if simple societal changes can help improve long-term outcomes in our children."
While inflammation does not mean an infection, infections can certainly cause inflammation. One can conclude the inflammatory processes and viral exposures that occur during pregnancy are not benign, and it is important to understand the immune system and reactionary processes. We need to learn their impact on developing fetuses, so as to better protect their vulnerable brains.
