title: Perinatal exposure to lead induces morphological, ultrastructural and molecular alterations in the hippocampus.
abstract: The aim of this paper is to examine if pre- and neonatal exposure to lead (Pb) may intensify or inhibit apoptosis or necroptosis in the developing rat brain. Pregnant experimental females received 0.1% lead acetate (PbAc) in drinking water from the first day of gestation until weaning of the offspring; the control group received distilled water. During the feeding of pups, mothers from the experimental group were still receiving PbAc. Pups were weaned at postnatal day 21 and the young rats of both groups then received only distilled water until postnatal day 28. This treatment protocol resulted in a concentration of Pb in rat offspring whole blood (Pb-B) below the threshold of 10 μg/dL, considered safe for humans.We studied Casp-3 activity and expression, AIF nuclear translocation, DNA fragmentation, as well as Bax, Bcl-2 mRNA and protein expression as well as BDNF concentration in selected structures of the rat brain: forebrain cortex (FC), cerebellum (C) and hippocampus (H). The microscopic examinations showed alterations in hippocampal neurons.Our data shows that pre- and neonatal exposure of rats to Pb, leading to Pb-B below 10 μg/dL, can decrease the number of hippocampus neurons, occurring concomitantly with ultrastructural alterations in this region. We observed no morphological or molecular features of severe apoptosis or necrosis (no active Casp-3 and AIF translocation to nucleus) in young brains, despite the reduced levels of BDNF. The potential protective factor against apoptosis was probably the decreased Bax/Bcl-2 ratio, which requires further investigation. Our findings contribute to further understanding of the mechanisms underlying Pb neurotoxicity and cognition impairment in a Pb-exposed developing brain.
authors.affiliation: Department of Biochemistry and Medical Chemistry, Pomeranian Medical University, Powstańców Wlkp. 72, 70-111 Szczecin, Poland. irena.bosiacka@ams.edu.pl
authors.forename: I
authors.initials: I
authors.lastname: Baranowska-Bosiacka
authors.forename: L
authors.initials: L
authors.lastname: Strużyńska
authors.forename: I
authors.initials: I
authors.lastname: Gutowska
authors.forename: A
authors.initials: A
authors.lastname: Machalińska
authors.forename: A
authors.initials: A
authors.lastname: Kolasa
authors.forename: P
authors.initials: P
authors.lastname: Kłos
authors.forename: G A
authors.initials: GA
authors.lastname: Czapski
authors.forename: M
authors.initials: M
authors.lastname: Kurzawski
authors.forename: A
authors.initials: A
authors.lastname: Prokopowicz
authors.forename: M
authors.initials: M
authors.lastname: Marchlewicz
authors.forename: K
authors.initials: K
authors.lastname: Safranow
authors.forename: B
authors.initials: B
authors.lastname: Machaliński
authors.forename: B
authors.initials: B
authors.lastname: Wiszniewska
authors.forename: D
authors.initials: D
authors.lastname: Chlubek
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000187:drug effects; D002531:Cerebellum / Q000187:drug effects / Q000473:pathology; D002540:Cerebral Cortex / Q000187:drug effects / Q000473:pathology; D003072:Cognition Disorders / Q000139:chemically induced / Q000503:physiopathology; D053938:DNA Fragmentation / Q000187:drug effects; D005260:Female; D006624:Hippocampus / Q000187:drug effects* / Q000473:pathology; D008297:Male; D009336:Necrosis; D009474:Neurons / Q000187:drug effects / Q000473:pathology; D020258:Neurotoxicity Syndromes / Q000209:etiology* / Q000473:pathology; D009942:Organometallic Compounds / Q000008:administration & dosage / Q000633:toxicity*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000473:pathology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D009942:Organometallic Compounds; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; C008261:lead acetate