TY - JOUR
T1 - Differential responses of hippocampal neurons and astrocytes to nicotine and hypoxia in the fetal guinea pig
AU - Blutstein, Tamara
AU - Castello, Michael A.
AU - Viechweg, Shaun S.
AU - Hadjimarkou, Maria M.
AU - McQuail, Joseph A.
AU - Holder, Mary
AU - Thompson, Loren P.
AU - Mong, Jessica A.
PY - 2013/7
Y1 - 2013/7
N2 - In utero exposure to cigarette smoke has severe consequences for the developing fetus, including increased risk of birth complications and behavioral and learning disabilities later in life. Evidence from animal models suggests that the cognitive deficits may be a consequence of in utero nicotine exposure in the brain during critical developmental periods. However, maternal smoking exposes the fetus to not only nicotine but also a hypoxic intrauterine environment. Thus, both nicotine and hypoxia are capable of initiating cellular cascades, leading to long-term changes in synaptic patterning that have the potential to affect cognitive functions. This study investigates the combined effect of in utero exposure to nicotine and hypoxia on neuronal and glial elements in the hippocampal CA1 field. Fetal guinea pigs were exposed in utero to normoxic or hypoxic conditions in the presence or absence of nicotine. Hypoxia increased the protein levels of matrix metalloproteinase-9 (MMP-9) and synaptophysin and decreased the neural density as measured by NeuN immunoreactivity (ir). Nicotine exposure had no effect on these neuronal parameters but dramatically increased the density of astrocytes immunopositive for glial fibrillary acidic protein (GFAP). Further investigation into the effects of in utero nicotine exposure revealed that both GFAP-ir and NeuN-ir in the CA1 field were significantly reduced in adulthood. Taken together, our data suggest that prenatal exposure to nicotine and hypoxia not only alters synaptic patterning acutely during fetal development, but that nicotine also has long-term consequences that are observed well into adulthood. Moreover, these effects most likely take place through distinct mechanisms.
AB - In utero exposure to cigarette smoke has severe consequences for the developing fetus, including increased risk of birth complications and behavioral and learning disabilities later in life. Evidence from animal models suggests that the cognitive deficits may be a consequence of in utero nicotine exposure in the brain during critical developmental periods. However, maternal smoking exposes the fetus to not only nicotine but also a hypoxic intrauterine environment. Thus, both nicotine and hypoxia are capable of initiating cellular cascades, leading to long-term changes in synaptic patterning that have the potential to affect cognitive functions. This study investigates the combined effect of in utero exposure to nicotine and hypoxia on neuronal and glial elements in the hippocampal CA1 field. Fetal guinea pigs were exposed in utero to normoxic or hypoxic conditions in the presence or absence of nicotine. Hypoxia increased the protein levels of matrix metalloproteinase-9 (MMP-9) and synaptophysin and decreased the neural density as measured by NeuN immunoreactivity (ir). Nicotine exposure had no effect on these neuronal parameters but dramatically increased the density of astrocytes immunopositive for glial fibrillary acidic protein (GFAP). Further investigation into the effects of in utero nicotine exposure revealed that both GFAP-ir and NeuN-ir in the CA1 field were significantly reduced in adulthood. Taken together, our data suggest that prenatal exposure to nicotine and hypoxia not only alters synaptic patterning acutely during fetal development, but that nicotine also has long-term consequences that are observed well into adulthood. Moreover, these effects most likely take place through distinct mechanisms.
KW - CNS development
KW - Glial fibrillary acidic protein
KW - Matrix metalloproteinase
KW - Neuronal insult
KW - Smoking
KW - Synaptic patterning
UR - http://www.scopus.com/inward/record.url?scp=84878376054&partnerID=8YFLogxK
U2 - 10.1007/s12640-012-9363-2
DO - 10.1007/s12640-012-9363-2
M3 - Article
C2 - 23192463
AN - SCOPUS:84878376054
SN - 1029-8428
VL - 24
SP - 80
EP - 93
JO - Neurotoxicity Research
JF - Neurotoxicity Research
IS - 1
ER -