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HERO ID
3421484
Reference Type
Journal Article
Title
Mild thyroid hormone insufficiency during development compromises activity-dependent neuroplasticity in the hippocampus of adult male rats
Author(s)
Gilbert, ME; Sanchez-Huerta, K; Wood, C
Year
2016
Is Peer Reviewed?
Yes
Journal
Endocrinology
ISSN:
0013-7227
EISSN:
1945-7170
Volume
157
Issue
2
Page Numbers
774-787
Language
English
PMID
26606422
DOI
10.1210/en.2015-1643
Web of Science Id
WOS:000369965900031
Relationship(s)
is supplemented by
3421493
: Supplemental data
Abstract
Severe thyroid hormone (TH) deficiency during critical phases of brain development results in irreversible neurological and cognitive impairments. The mechanisms accounting for this are likely multifactorial, and are not fully understood. Here we pursue the possibility that one important element is that TH affects basal and activity-dependent neurotrophin expression in brain regions important for neural processing. Graded exposure to propylthiouracil (PTU) during development produced dose-dependent reductions in mRNA expression of nerve growth factor (Ngf) in whole hippocampus of neonates. These changes in basal expression persisted to adulthood despite the return to euthyroid conditions in blood. In contrast to small PTU-induced reductions in basal expression of several genes, developmental PTU treatment dramatically reduced the activity-dependent expression of neurotrophins and related genes (Bdnf(t), Bdnf(iv), Arc, and Klf9) in adulthood and was accompanied by deficits in hippocampal-based learning. These data demonstrate that mild TH insufficiency during development not only reduces expression of important neurotrophins that persists into adulthood but also severely restricts the activity-dependent induction of these genes. Considering the importance of these neurotrophins for sculpting the structural and functional synaptic architecture in the developing and the mature brain, it is likely that TH-mediated deficits in these plasticity mechanisms contribute to the cognitive deficiencies that accompany developmental TH compromise.
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IRIS
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Hexabromocyclododecane (HBCD)
Guidance/contextual references added during assessment development
OPPT REs
•
OPPT_Cyclic Aliphatic Bromine Cluster (HBCD)_C. Engineering
Data screening total
Screening: Excluded
•
OPPT_Cyclic Aliphatic Bromine Cluster (HBCD)_D. Exposure
Total – title/abstract screening
Off topic
•
OPPT_Cyclic Aliphatic Bromine Cluster (HBCD)_E. Fate
Total – title/abstract screening
Off topic
•
OPPT_Cyclic Aliphatic Bromine Cluster (HBCD)_F. Human Health
Total – title/abstract screening
Off topic
•
PFBA
Supplemental References
•
PFBS
Included
Supporting References
•
PFHxS
•
PFNA
•
Third Biofuels Report to Congress
50% to 100%
50% to 100%
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