TY - JOUR
T1 - Effects of occlusal disharmony on the hippocampal dentate gyrus in aged senescence-accelerated mouse prone 8 (SAMP8)
AU - Mori, Daisuke
AU - Miyake, Hidekazu
AU - Mizutani, Kenmei
AU - Shimpo, Kan
AU - Sonoda, Shigeru
AU - Yamamoto, Toshiharu
AU - Fujiwara, Shuu
AU - Kubo, Kin Ya
N1 - Publisher Copyright:
© 2016 Elsevier Ltd. All rights reserved.
PY - 2016/5
Y1 - 2016/5
N2 - Background and objective Malocclusion induced by raising the bite causes chronic stress. Chronic stress leads to increased plasma corticosterone levels and impaired hippocampal function due to impaired neurogenesis or increased apoptosis in the hippocampus. The present study aimed to clarify the mechanisms underlying the impaired hippocampal function induced by the bite-raised condition in aged senescence-accelerated mouse prone 8 (SAMP8). Design Nine-month-old aged SAMP8 mice were randomly divided into control and bite-raised groups. The vertical dimension of the bite was raised by applying resin to the molars. We evaluated newborn cell proliferation, survival, differentiation, and apoptosis in the hippocampal dentate gyrus (DG). Hippocampal brain-derived neurotrophic factor (BDNF) levels were also measured. Results The bite-raised mice exhibited a significant decrease in proliferation, survival, and differentiation of newborn cells into neurons in the hippocampal DG compared with controls. The number of apoptotic cells in the hippocampal DG was increased at 7 and 14 days after the bite-raising procedure. Expression of BDNF protein and mRNA in the hippocampus was also decreased in the bite-raised mice. Conclusion Bite-raised aged SAMP8 mice exhibited decreased neurogenesis, increased apoptosis in the hippocampal DG, and decreased hippocampal BDNF expression, in association with hippocampus-dependent learning and memory deficits.
AB - Background and objective Malocclusion induced by raising the bite causes chronic stress. Chronic stress leads to increased plasma corticosterone levels and impaired hippocampal function due to impaired neurogenesis or increased apoptosis in the hippocampus. The present study aimed to clarify the mechanisms underlying the impaired hippocampal function induced by the bite-raised condition in aged senescence-accelerated mouse prone 8 (SAMP8). Design Nine-month-old aged SAMP8 mice were randomly divided into control and bite-raised groups. The vertical dimension of the bite was raised by applying resin to the molars. We evaluated newborn cell proliferation, survival, differentiation, and apoptosis in the hippocampal dentate gyrus (DG). Hippocampal brain-derived neurotrophic factor (BDNF) levels were also measured. Results The bite-raised mice exhibited a significant decrease in proliferation, survival, and differentiation of newborn cells into neurons in the hippocampal DG compared with controls. The number of apoptotic cells in the hippocampal DG was increased at 7 and 14 days after the bite-raising procedure. Expression of BDNF protein and mRNA in the hippocampus was also decreased in the bite-raised mice. Conclusion Bite-raised aged SAMP8 mice exhibited decreased neurogenesis, increased apoptosis in the hippocampal DG, and decreased hippocampal BDNF expression, in association with hippocampus-dependent learning and memory deficits.
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U2 - 10.1016/j.archoralbio.2016.01.015
DO - 10.1016/j.archoralbio.2016.01.015
M3 - Article
C2 - 26874024
AN - SCOPUS:84957916905
SN - 0003-9969
VL - 65
SP - 95
EP - 101
JO - Archives of Oral Biology
JF - Archives of Oral Biology
ER -