Adverse effects of prenatal tobacco smoke exposure on biological parameters of the developing brainstem.
We aimed to study the consequences of chronic exposure to tobacco smoke in utero on the morphological and functional maturation of the brainstem by comparing stillbirths of smoker mothers versus nonsmoker mothers. A total of 42 stillbirths, aged 25-40 gestational weeks, underwent autopsy according to our guidelines (). The brainstem was studied on serial sections and by immunohistochemistry to assay the expression of the EN2 gene, somatostatin (SS) and the tyrosine hydroxylase enzyme (TH). We observed a significant correlation between maternal smoking and sudden intrauterine unexplained death (SIUD), hypoplasia of the ArcN, no immunostaining of the EN2 in the arcuate nucleus (ArcN), and of TH in the locus coeruleus (LC) (P < 0.05). An increased incidence of maternal smoking was also observed in fetuses with SS negativity in the hypoglossus nucleus (HypoglN). Exposure in utero to maternal smoking may strongly interfere with brain biological parameters, giving rise not only to structural developmental abnormalities of the arcuate nucleus, but also to a decrease of noradrenergic activity in the LC, of EN2 gene expression in the ArcN and of SS in the HypoglN.
Lavezzi
Anna Maria
AM
Institute of Pathology, Lino Rossi Research Center for the Study and Prevention of Unexpected Perinatal Death and Sudden Infant Death Syndrome (SIDS), University of Milan, Via della Commenda, 19, 20122 Milan, Italy. anna.lavezzi@unimi.it
Ottaviani
Giulia
G
Matturri
Luigi
L
D001933:Brain Stem / Q000002:abnormalities / Q000187:drug effects* / Q000473:pathology; D002320:Cardiovascular Physiological Phenomena / Q000187:drug effects; D005260:Female; D005313:Fetal Death / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology; D005333:Fetus / Q000002:abnormalities / Q000187:drug effects* / Q000503:physiopathology; D018398:Homeodomain Proteins / Q000378:metabolism; D006801:Humans; D007002:Hypoglossal Nerve / Q000187:drug effects / Q000378:metabolism; D007150:Immunohistochemistry; D008125:Locus Coeruleus / Q000187:drug effects / Q000378:metabolism; D008526:Medulla Oblongata / Q000002:abnormalities / Q000187:drug effects / Q000473:pathology; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009421:Nervous System Malformations / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology; D009638:Norepinephrine / Q000378:metabolism; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000139:chemically induced* / Q000473:pathology / Q000503:physiopathology; D012143:Respiratory Physiological Phenomena / Q000187:drug effects; D013004:Somatostatin / Q000378:metabolism; D050497:Stillbirth; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism; D014026:Nicotiana; D000099266:Engrailed 2 Protein
D018398:Homeodomain Proteins; D009419:Nerve Tissue Proteins; D009638:Norepinephrine; D013004:Somatostatin; D014446:Tyrosine 3-Monooxygenase; D000099266:Engrailed 2 Protein