TY - JOUR
T1 - Soft-diet feeding after weaning affects behavior in mice
T2 - Potential increase in vulnerability to mental disorders
AU - Nose-Ishibashi, K.
AU - Watahiki, J.
AU - Yamada, K.
AU - Maekawa, M.
AU - Watanabe, A.
AU - Yamamoto, G.
AU - Enomoto, A.
AU - Matsuba, Y.
AU - Nampo, T.
AU - Taguchi, T.
AU - Ichikawa, Y.
AU - Saido, T. C.
AU - Mishima, K.
AU - Yamaguchi, Y.
AU - Yoshikawa, T.
AU - Maki, K.
N1 - Funding Information:
This work was funded by a grant from JSPS KAKENHI (No. 21792096 ). This study was supported by the Laboratory for Molecular Psychiatry, RIKEN Brain Science Institute, Saitama, Japan . The equipment was provided by Research Resource Center, RIKEN Brain Science Institute, Saitama, Japan.
PY - 2014/3/28
Y1 - 2014/3/28
N2 - Mastication is one of the most important oral functions, and the period during which mastication is acquired overlaps with the term of rapid development and maturation of the neural systems. In particular, the acquisition period after weaning is related to the potential onset of mental disorders. However, the roles of mastication during this period for brain development remain largely unknown. Therefore, we used a series of standard behavioral analyses, assessment of hippocampal cell proliferation, and the expression of brain-derived neurotrophic factor (BDNF), TrkB, and Akt1 in the hippocampus and frontal cortex of mice to investigate the effects of post-weaning mastication on brain function. We fed 21-day-old C57BL6/J male mice either a hard or a soft diet for 4. weeks and conducted a series of standard behavioral tests from 7. weeks of age. Further, histological analysis with bromodeoxyuridine was performed to compare hippocampal cell proliferation at 7 and 14. weeks of age. Real-time polymerase chain reaction was performed to compare BDNF, TrkB, and Akt1 expression in the hippocampus and frontal cortex of 14-week-old mice.Compared to mice fed a hard diet (HDM), soft-diet mice (SDM) showed behavioral impairments, including decreased home cage activity, increased open field test activity, and deficits in prepulse inhibition. These results were similar to those observed in mouse models of schizophrenia. However, no effects were observed on anxiety-like behaviors or memory/learning tests. Compared to HDM, SDM showed significantly decreased hippocampal cell proliferation and hippocampal BDNF and Akt1 gene expression at 14. weeks of age. A soft diet after weaning may have resulted in histological and molecular changes in the hippocampus and influenced outcomes of behavioral tests related to mental disorders.Our findings suggest that soft-diet feeding after weaning may affect both physical and mental development of mice, and may increase vulnerability to mental disorders.
AB - Mastication is one of the most important oral functions, and the period during which mastication is acquired overlaps with the term of rapid development and maturation of the neural systems. In particular, the acquisition period after weaning is related to the potential onset of mental disorders. However, the roles of mastication during this period for brain development remain largely unknown. Therefore, we used a series of standard behavioral analyses, assessment of hippocampal cell proliferation, and the expression of brain-derived neurotrophic factor (BDNF), TrkB, and Akt1 in the hippocampus and frontal cortex of mice to investigate the effects of post-weaning mastication on brain function. We fed 21-day-old C57BL6/J male mice either a hard or a soft diet for 4. weeks and conducted a series of standard behavioral tests from 7. weeks of age. Further, histological analysis with bromodeoxyuridine was performed to compare hippocampal cell proliferation at 7 and 14. weeks of age. Real-time polymerase chain reaction was performed to compare BDNF, TrkB, and Akt1 expression in the hippocampus and frontal cortex of 14-week-old mice.Compared to mice fed a hard diet (HDM), soft-diet mice (SDM) showed behavioral impairments, including decreased home cage activity, increased open field test activity, and deficits in prepulse inhibition. These results were similar to those observed in mouse models of schizophrenia. However, no effects were observed on anxiety-like behaviors or memory/learning tests. Compared to HDM, SDM showed significantly decreased hippocampal cell proliferation and hippocampal BDNF and Akt1 gene expression at 14. weeks of age. A soft diet after weaning may have resulted in histological and molecular changes in the hippocampus and influenced outcomes of behavioral tests related to mental disorders.Our findings suggest that soft-diet feeding after weaning may affect both physical and mental development of mice, and may increase vulnerability to mental disorders.
KW - Behavioral analysis
KW - Brain-derived neurotrophic factor
KW - Mental disorder; neurogenesis
KW - Prepulse inhibition
KW - Soft-diet feeding
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UR - http://www.scopus.com/inward/citedby.url?scp=84896740342&partnerID=8YFLogxK
U2 - 10.1016/j.neuroscience.2013.12.065
DO - 10.1016/j.neuroscience.2013.12.065
M3 - Article
C2 - 24444829
AN - SCOPUS:84896740342
SN - 0306-4522
VL - 263
SP - 257
EP - 268
JO - Neuroscience
JF - Neuroscience
ER -
