Prenatal Exposure to Artificial Light at Night and the Offspring’s First 1000-Day Growth: A Prospective Metabolomic and Gene-Environment Interaction Study

Our previous exposome study suggested associations between
prenatal
exposure to artificial light at night (ALAN) and offspring weight
and fat growth during the first 1000 days. This study aims to further
explore the underlying biomechanism and modifying effects of maternal
genetic regulators. Among 1944 mother-child pairs from the Shanghai
Birth Cohort, meet-in-the-middle, mediation, and enrichment analyses
were combined with the early pregnancy untargeted metabolome to explore
potential biological links between prenatal ALAN exposure and early
life growth. Maternal polygenetic risk scores (PRS) for glucose- and
lipid-metabolism-related phenotypes were constructed and dichotomized
(high/low) to examine gene-environment interactions. We identified
35 mediating metabolites between prenatal ALAN exposure and growth
outcomes, which were enriched in neural signal transduction-related
pathways and associated with the circadian rhythm. The effects of
ALAN exposure on fetal and child growth were more pronounced among
mothers with high PRS levels for fasting glucose, HbA1c, and triglycerides.
To sum up, prenatal ALAN exposure may be associated with reduced weight
and adiposity gains during the first 1000 days. These associations
may be partly explained by disturbances in maternal circadian rhythms
and appeared more pronounced among mothers with high genetic predispositions
to glucose and triglyceride levels.