New Study Shows Third Trimester as a Critical Period for Inflammatory Regulation
Previous research suggests that strong inflammatory states are associated with autism spectrum disorder (ASD). Other investigations have proposed that inflammation could be linked to the etiology of many neurodegenerative diseases, including autism. Until now, determining when atypical inflammatory regulation begins has not been possible. However, a new study involving Dr. Manish Arora and other researchers may have found an approach to determine when this abnormal process begins. The authors presented a method that could generate approximately daily profiles of prenatal and early childhood inflammation as measured by developmentally archived C-reactive protein (CRP) in incremental layers of deciduous (i.e., baby) tooth dentin. CRP is one of the most commonly studied biomarkers of inflammation. The protein has also been implicated in the development of ASD. Using a group of Swedish twins as research subjects, the authors found heightened inflammation CRP markers in tooth dentin in the third trimester of children with future ASD diagnosis relative to controls (n = 66; 14 ASD cases; critical window: −90 to −50 days before birth). To confirm their finding, the authors ran a replication study in the United States and observed a similar increase in CRP in ASD cases during the third trimester (n = 47; 23 ASD cases; −128 to −21 days before birth). The authors believe their findings indicate that the third trimester is critical for atypical fetal inflammatory regulation in ASD, especially for male fetuses. They also suggest that, unlike prior studies, their study shows that the prenatal inflammatory signal comes from the fetal rather than the maternal environment.
