Influence of circadian rhythm on effects induced by mechanical strain in periodontal ligament cells.
J Orofac Orthop
; 2024 Aug 12.
Article
in En
| MEDLINE
| ID: mdl-39134880
ABSTRACT
PURPOSE:
The aim of this study was to investigate the influence of mechanical strain on clock gene function in periodontal ligament (PDL) cells. Furthermore, we wanted to analyze whether effects induced by mechanical stress vary in relation to the circadian rhythm.METHODS:
Human PDL fibroblasts were synchronized in their circadian rhythm with dexamethasone and stretched over 24â¯h. Unstretched cells served as controls. Gene expression of the core clock genes were analyzed at 4â¯h intervals by quantitative real-time polymerase chain reaction (qRT-PCR). Time points 0â¯h (group SI1) and 12â¯h (group SI2) after synchronization served as starting points of a 4â¯h force application period. Collagen-1α (COL-1α/Col-1α), interleukin-1ß (IL1-ß), and runt-related transcription factor 2 (RUNX2/Runx2) were assessed by qRT-PCR and enzyme-linked immunosorbent assay (ELISA) after 2 and 4â¯h. Statistical analysis comprised one-way analysis of variance (ANOVA) and post hoc tests.RESULTS:
After synchronization, the typical pattern for clock genes was visible in control cells over the 24â¯h period. This pattern was significantly altered by mechanical strain. Under tensile stress, ARNTL gene expression was reduced, while Per1 and 2 gene expression were upregulated. In addition, mechanical stress had a differential effect on the expression of Col-1α and IL1ß depending on its initiation within the circadian rhythm (group SI1 vs group SI2). For RUNX2, no significant differences in the two groups were observed.CONCLUSION:
Our results suggest that mechanical stress affects the molecular peripheral oscillator of PDL cells. Vice versa, the circadian rhythm also seems to partially influence the effects that mechanical stress exerts on PDL cells.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
J Orofac Orthop
/
J. orofac. orthop
/
Journal of orofacial orthopedics
Year:
2024
Document type:
Article