The effects of hypoxia inducible factor-1α in myeloid cells and a high-salt diet in a mouse model of orthodontic tooth movement
6
조회
0
다운로드
0
인용
0
참고문헌
키워드
초록
Objective: Force application during orthodontic tooth movement (OTM) promotes oxygen depletion and bone remodeling. Deficiency of hypoxia inducible factor-1α (HIF1α ) in myeloid cells accelerates OTM. Low-oxygen and high-salt conditions can stabilize HIF1α in myeloid cells. This study aimed to determine whether myeloid HIF1α levels influence OTM under low- and high-salt diets in mice. Methods: Mice with and without HIF1α expression in myeloid cells received a low-salt (< 0.03% NaCl, tap water) or an high-salt (4% NaCl, saline) diet for two weeks. One week after the start of the diet, an elastic band was inserted between the first and second molars. The expression of inflammatory and bone remodeling genes, bone density, and extent of OTM were determined. Results: Myeloid Hif1α expression did not modify high-saltinduced expression of the inflammatory genes interleukin-1β and interleukin-6. Myeloid-derived Hif1α and dietary salt levels did not significantly modify osteoblast responses to OTM. High-salt conditions and myeloid Hif1α deletion increased osteoclast numbers and expression of osteoclast-specific genes. This was paralleled by reduced bone density, which ultimately led to increased OTM. Conclusions: A high-salt diet and the absence of HIF1α both lead to increased OTM. In the tested OTM model, exposure to high-salt conditions was largely independent of myeloid cell-derived HIF1α.
Abstract
Objective: Force application during orthodontic tooth movement (OTM) promotes oxygen depletion and bone remodeling. Deficiency of hypoxia inducible factor-1α (HIF1α ) in myeloid cells accelerates OTM. Low-oxygen and high-salt conditions can stabilize HIF1α in myeloid cells. This study aimed to determine whether myeloid HIF1α levels influence OTM under low- and high-salt diets in mice. Methods: Mice with and without HIF1α expression in myeloid cells received a low-salt (< 0.03% NaCl, tap water) or an high-salt (4% NaCl, saline) diet for two weeks. One week after the start of the diet, an elastic band was inserted between the first and second molars. The expression of inflammatory and bone remodeling genes, bone density, and extent of OTM were determined. Results: Myeloid Hif1α expression did not modify high-saltinduced expression of the inflammatory genes interleukin-1β and interleukin-6. Myeloid-derived Hif1α and dietary salt levels did not significantly modify osteoblast responses to OTM. High-salt conditions and myeloid Hif1α deletion increased osteoclast numbers and expression of osteoclast-specific genes. This was paralleled by reduced bone density, which ultimately led to increased OTM. Conclusions: A high-salt diet and the absence of HIF1α both lead to increased OTM. In the tested OTM model, exposure to high-salt conditions was largely independent of myeloid cell-derived HIF1α.