title: Mitochondrial Gene Expression Profiles Are Associated with Maternal Psychosocial Stress in Pregnancy and Infant Temperament.
abstract: BACKGROUND
  Gene-environment interactions mediate through the placenta and shape the fetal brain development. Between the environmental determinants of the fetal brain, maternal psychosocial stress in pregnancy has been shown to negatively influence the infant temperament development. This in turn may have adverse consequences on the infant neurodevelopment extending throughout the entire life-span. However little is known about the underlying biological mechanisms of the effects of maternal psychosocial stress in pregnancy on infant temperament. Environmental stressors such as maternal psychosocial stress in pregnancy activate the stress response cascade that in turn drives the increase in the cellular energy demand of vital organs with high metabolic rates such as, in pregnancy, the placenta. Key players of the stress response cascade are the mitochondria.
  
  
  RESULTS
  Here, we tested the expression of all 13 protein-coding genes encoded by the mitochondria in 108 placenta samples from the Stress in Pregnancy birth cohort, a study that aims at determining the influence of in utero exposure to maternal psychosocial stress in pregnancy on infant temperament. We showed that the expression of the protein-coding mitochondrial-encoded gene MT-ND2 was positively associated with indices of maternal psychosocial stress in pregnancy including Prenatal Perceived Stress (β = 0.259; p-regression = 0.004; r2-regression = 0.120), State Anxiety (β = 0.218; p-regression = 0.003; r2-regression = 0.153), Trait Anxiety (β = 0.262; p-regression = 0.003; r2-regression = 0.129) and Pregnancy Anxiety Total (β = 0.208; p-regression = 0.010; r2-regression = 0.103). In the meantime MT-ND2 was negatively associated with the infant temperament indices of Activity Level (β = -0.257; p-regression = 0.008; r2-regression = 0.165) and Smile and Laughter (β = -0.286; p-regression = 0.036; r2-regression = 0.082). Additionally, MT-ND6 was associated with the maternal psychosocial stress in pregnancy index of Prenatal Perceived Stress (β = -0.231; p-regression = 0.004; r2-regression = 0.120), while MT-CO2 was associated with the maternal psychosocial stress in pregnancy indices of State Anxiety (β = 0.206; p-regression = 0.003; r2-regression = 0.153) and Trait Anxiety (β = 0.205; p-regression = 0.003; r2-regression = 0.129).
  
  
  CONCLUSIONS
  Our data support the role of mitochondria in responding to maternal psychosocial stress in pregnancy, as assessed in placenta, while also suggesting an important role for the mitochondria in the infant temperament development.
authors.affiliation: Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America; Department of Obstetrics, Gynecology and Reproductive Science, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America.
authors.forename: Luca
authors.initials: L
authors.lastname: Lambertini
authors.affiliation: Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America; Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America; Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America.
authors.forename: Jia
authors.initials: J
authors.lastname: Chen
authors.affiliation: Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America; Department of Psychology, Queens College, CUNY, Flushing, New York, United States of America; Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Nomura
mesh_terms: D000328:Adult; D015331:Cohort Studies; D005260:Female; D047109:Fetal Development; D050259:Genes, Mitochondrial / Q000235:genetics*; D006801:Humans; D007223:Infant; D018730:Infant Behavior / Q000502:physiology*; D008297:Male; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D011248:Pregnancy Complications / Q000235:genetics* / Q000523:psychology*; D013315:Stress, Psychological / Q000235:genetics*; D013694:Temperament / Q000502:physiology*; D059467:Transcriptome