Department of Pediatric Dentistry, Stomatological Hospital, Southern Medical University, Guangzhou, 510280, Guangdong, China.
Department of Prosthodontics, School and Hospital of Stomatology, Fujian Medical University, Fuzhou, 350002, Fujian, China.
Clin Oral Investig. 2022 Aug;26(8):5205-5213. doi: 10.1007/s00784-022-04488-9. Epub 2022 Apr 20.
This study was designed to explore the effects of mechanical force on the proliferation, apoptosis, and morphology of stem cells from human exfoliated deciduous tooth pulp (SHEDs).
Caries-free stranded deciduous teeth were extracted, and SHEDs were isolated through enzymatic digestion. The cultured SHEDs were subjected to different levels of mechanical stimuli (0, 100, 200, and 300 g) for 7 days (30 min/day) using external centrifugal force. Cell proliferation was evaluated with the CCK-8 assay, and the cell cycle and apoptosis were assessed by flow cytometry. The cell morphology was examined using transmission electron microscopy.
Cell proliferation assay showed no differences between the three stimulation groups and the control group in day 1 to day 3. From the 4th day, cell proliferation was significantly lower in the mechanical force groups than in the control group, but no significant difference was observed among the three mechanical force groups. Besides, there was no significant difference in cell apoptosis among the four groups for 7 days. On day 7 after stimulation, the SHEDs were shrunken, with significantly increased isochromosome in the nucleus and an increase in lysosomes.
Mechanical force can inhibit the proliferation and affect morphology of SHEDs, but it has no effect on cell apoptosis.
Mechanical force stimulation significantly inhibited cell proliferation of SHEDs. Mechanical force stimulation had no significant effect on cell apoptosis of SHEDs. The morphology and ultrastructure of SHEDs changed after mechanical force stimulation.
本研究旨在探讨机械力对人脱落乳牙牙髓干细胞（SHED）增殖、凋亡和形态的影响。
从无龋脱落乳牙中提取 SHED，通过酶消化分离培养。将培养的 SHED 置于不同水平的机械刺激（0、100、200 和 300 g）下，通过外部离心力刺激 7 天（每天 30 分钟）。采用 CCK-8 法检测细胞增殖，采用流式细胞术检测细胞周期和凋亡。采用透射电子显微镜观察细胞形态。
细胞增殖试验显示，在第 1 天至第 3 天，三组刺激组与对照组之间的细胞增殖无差异。从第 4 天开始，机械力组的细胞增殖明显低于对照组，但三组机械力组之间无显著差异。此外，在 7 天的刺激过程中，四个组的细胞凋亡均无显著差异。在刺激后第 7 天，SHED 细胞皱缩，核内异染色质明显增加，溶酶体增加。
机械力可抑制 SHED 的增殖并影响其形态，但对细胞凋亡无影响。
机械力刺激可显著抑制 SHED 的细胞增殖。机械力刺激对 SHED 的细胞凋亡无明显影响。机械力刺激后 SHED 的形态和超微结构发生改变。
