title: A novel mechanical loading model for studying the distributions of strain and mechano-growth factor expression.
abstract: Mechano-growth factor (MGF), an insulin-like growth factor-I (IGF-I) splice variant, often serves as an important local tissue repair factor in response to the mechanical environment. However, there is no model for exhibiting the MGF expression in a series of strain distribution up to now. In this study, a novel mechanical loading model containing different stresses and strains simultaneously was developed to examine the MGF expression. The strain distributions were predicted by finite element modeling. The MC3T3-E1 cells on a silicone membrane with a central circular hole were exposed to a variable strain environment through stretching. The finite element analysis showed that, when the strain reached the magnitude of 10%, the strain concentration near the circular hole displayed along with the vertical stretch direction, while the minimum strain appeared in the parallel stretch direction. Furthermore, the results showed that MGF expression decreased gradually from high to low strain regions by immunocytochemistry. Meanwhile, the proliferation of osteoblasts increased significantly in the high strain region. In conclusion, this mechanical loading model can present the different distributions of the strain of osteoblasts in vitro. MGF expression and osteoblast proliferation have a high correlation with the levels of strain.
authors.affiliation: Key Laboratory of Biorheological Science and Technology, Chongqing University, Ministry of Education, Chongqing 400030, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Peng
authors.forename: Yuanliang
authors.initials: Y
authors.lastname: Wang
authors.forename: Juhui
authors.initials: J
authors.lastname: Qiu
authors.forename: Bingbing
authors.initials: B
authors.lastname: Zhang
authors.forename: Jiaoxia
authors.initials: J
authors.lastname: Sun
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Lv
authors.forename: Li
authors.initials: L
authors.lastname: Yang
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001696:Biomechanical Phenomena; D001842:Bone and Bones / Q000166:cytology / Q000502:physiology*; D049109:Cell Proliferation; D020342:Finite Element Analysis; D007150:Immunohistochemistry; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D051379:Mice; D008954:Models, Biological; D010006:Osteoblasts / Q000166:cytology / Q000502:physiology*; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D013314:Stress, Mechanical; D016474:Weight-Bearing / Q000502:physiology
chemical_list: D018809:Proliferating Cell Nuclear Antigen; C527564:mechano-growth factor, mouse; D007334:Insulin-Like Growth Factor I