Influence of Circadian Disruption on Dentin Development in Mice

doi:10.13701/j.cnki.kqyxyj.2022.08.007

Abstract

Abstract: Objective: To investigate the effect of circadian disruption during dentin formation. Methods: The model of environmental circadian disruption was constructed in mice and immunohistochemistry (IHC) was employed to detect the expression of BMAL1, PER2, and DSPP in molar germs in offspring of pregnant mice. Mouse dental papilla cells (mDPCs) were separated from Kunming mice at postnatal day 1 (PN1). After synchronization, the cells were cultured for 48h and harvested every 6h. qRT-PCR was used to explore the expression of Bmal1 and Per2. Scanning electron microscope (SEM) was used to compare the structure of dentinal tubules in the sagittal plane of incisor and molar in control and disturbance group. Energy-dispersive X-ray spectroscopy (EDS) was performed for surface elements analysis of mandibular incisors. The mineral density of dentin in both groups was compared and analyzed. Results: The expression of BMAL1, PER2, and DSPP decreased in the mandibular first molar germs of circadian rhythm disturbance group compared with the control group. Moreover, during 48h period, Bmal1 and Per2 exhibited a rhythmic profile in synchronized mouse dental papilla cells. The element weight percent of Ca and the value of the Ca/P ratio were reduced in disturbance group compared with those in the control group. The results of SEM and mineral density of dentin exhibited no obvious abnormalities. Conclusion: Circadian rhythm might involve in regulating dentin development.

Key words: dental papilla cells, circadian gene, circadian disruption

LI Ruiqi, HUANG Wushuang, LI Shiyu, ZHENG Xueqing, LIU Nianke, SONG Yaling. Influence of Circadian Disruption on Dentin Development in Mice[J]. Journal of Oral Science Research, 2022, 38(8): 731-735.

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