Qiong Liu1, Hong Qian2, Hao Yu3, Fei Ren1, Jingxiao Fang1, Fang Liu1, Hedi Liu1, Jianying Liang1. 1. Department of Pediatric Dentistry, Stomatological Hospital, Southern Medical University, Guangzhou, 510280, Guangdong, China. 2. Department of Pediatric Dentistry, Stomatological Hospital, Southern Medical University, Guangzhou, 510280, Guangdong, China. qianhongsmu@126.com. 3. Department of Prosthodontics, School and Hospital of Stomatology, Fujian Medical University, Fuzhou, 350002, Fujian, China.
Abstract
OBJECTIVES: 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). MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSIONS: Mechanical force can inhibit the proliferation and affect morphology of SHEDs, but it has no effect on cell apoptosis. CLINICAL RELEVANCE: 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.
OBJECTIVES: 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). MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSIONS: Mechanical force can inhibit the proliferation and affect morphology of SHEDs, but it has no effect on cell apoptosis. CLINICAL RELEVANCE: 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.
Authors: Masako Miura; Stan Gronthos; Mingrui Zhao; Bai Lu; Larry W Fisher; Pamela Gehron Robey; Songtao Shi Journal: Proc Natl Acad Sci U S A Date: 2003-04-25 Impact factor: 11.205