Maternal Exercise Prior to and During Gestation Induces Sex-Specific Alterations in the Mouse Placenta

Examined the role of maternal voluntary wheel running commencing 10 weeks prior to gestation, and throughout pregnancy, on placental transcriptome in late gestation While exercise (EX) is beneficial during pregnancy for both mother and child, little is known about the mechanisms by which maternal (MAT EX) mediates changes in utero. We hypothesized that effects of MAT EX prior to and during gestation will be evident in transcriptomic signatures in the placenta and will be sexually dimorphic. Six-week-old female C57BL/6 mice were divided into 2 groups; with (exercise, EX; N = 7) or without (sedentary, SED; N = 8) access to voluntary running wheels. EX was provided via 24-hour access to wheels for 10 weeks prior to conception until late pregnancy (18.5 days post coitum). Sex-stratified placenta and fetal livers were collected. Mi-croarray analysis of SED and EX placenta revealed that MAT EX affected gene transcript expression of 283 and 661 transcripts in male and female placenta (±1.4-fold, p < 0.05). Gene-set enrichment and Ingenuity Pathway analyses of male placenta showed that MAT EX led to inhibition of sig-naling pathways, biological functions, and down regulation of transcripts related to lipid and steroid, while MAT EX in female placentas led to activation of pathways, biological functions, and gene expression related to muscle growth, brain, vascular development, and growth factors. Overall, our results suggest that effects of MAT EX on the placenta and presumably on the offspring are influenced by maternal habitus and are sexually dimorphic. Overall design: Six microarrays were used for each group (Sedentary vs Exercise), representing six placentas per group. A n=3 microarrays per sex/group were used (ie n=3 male_SED, n=3 female_SED, n=3 Male_EX, N=3 female_EX)