title: [Effect of different mechanical loading on the expression of Notch signaling pathways in growing rabbits' condylar cartilage].
abstract: Objective:To investigate the effect of different mechanical loading on the expression of Notch-1, Notch-3, Jagged-1 and Delta-like-1 in growing rabbits' condylar cartilage.Methods:Sixty-four ten-days-old rabbits were randomly divided into experimental and control groups. The rabbits in the experimental groups were fed on a powder diet, while the control groups were fed on a solid diet. The animals were sacrificed after 2, 4, 6 and 8 weeks. Notch-1, Notch-3, Jagged-1 and Delta-like-1 gene and protein expressions were examined by HE, immunohistochemistry, Western blotting and quantitative real-time PCR.Results:At 2, 4, 6, 8 weeks, the anterior part of condylar cartilage in solid diet groups ([318.1±4.3], [342.4±2.6], [364.2±3.2], [380.7±6.0] mm, respectively) were thicker than those in powder diet groups ([275.4±2.6], [301.1±2.0], [322.3±3.3], [366.5±8.4] mm, respectively) (P<0.05). There was no significant difference between the two groups in the middle part (P>0.05). From 2 to 6 weeks, the posterior part of cartilage in solid diet groups ([444.1±1.5], [451.1±0.3], [476.4±5.7] mm, respectively) was thinner than those in power diet groups ([470.4±2.7], [494.3±2.9], [512.3±5.7] mm, respectively) (P<0.05). At 6 weeks, there were more mRNA expressions of Notch-3, Jagged-1 and Delta-like-1 in solid diet group than in power diet group (P<0.05). The Notch-1 protein could be found in all layers of condylar cartilage, especially in the surface of hypertrophic zone. The expressions of Notch-1, Notch-3, and Delta-like-1 protein were increased from 2 to 6 weeks, and decreased at 8 weeks. In solid diet groups, the protein expressions of Notch-1 (at 2, 4, 6, 8 weeks), Notch-3 (at 2, 4, 6 weeks), Jagged-1 (at 2, 4, 6 weeks) and Delta-like-1 (at 4, 6, 8 weeks) were greater than in power diet groups (P<0.05).Conclusions:Low masticatory loading may delay or inhibit the development of condylar cartilage and its growing factors such as Notch-1, Notch-3, Jagged-1 and Delta-like-1. Appropriate masticatory loading plays an important role in normal development of the condyle.
authors.affiliation: Department of Orthodontics, The School of Stomatology, Zhejiang Chinese Medical University, Hangzhou 310053, China.
authors.forename: F
authors.initials: F
authors.lastname: Yan
authors.affiliation: Department of Orthodontics, The School of Stomatology, Zhejiang Chinese Medical University, Hangzhou 310053, China.
authors.forename: J Y
authors.initials: JY
authors.lastname: Feng
authors.affiliation: Department of Orthodontics, The School of Stomatology, Zhejiang Chinese Medical University, Hangzhou 310053, China.
authors.forename: T C
authors.initials: TC
authors.lastname: Mou
authors.affiliation: Department of Orthodontics, The School of Stomatology, Zhejiang Chinese Medical University, Hangzhou 310053, China.
authors.forename: C Y
authors.initials: CY
authors.lastname: Liu
authors.affiliation: Department of Orthodontics, The School of Stomatology, Zhejiang Chinese Medical University, Hangzhou 310053, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Sun
authors.affiliation: Department of Orthodontics, The School of Stomatology, Zhejiang Chinese Medical University, Hangzhou 310053, China.
authors.forename: C J
authors.initials: CJ
authors.lastname: Shi
mesh_terms: D000818:Animals; D002358:Cartilage, Articular / Q000378:metabolism*; D004032:Diet; D015870:Gene Expression; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D000072100:Jagged-1 Protein / Q000378:metabolism*; D008335:Mandibular Condyle / Q000254:growth & development / Q000378:metabolism*; D008409:Mastication / Q000502:physiology; D008565:Membrane Proteins / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011817:Rabbits; D011897:Random Allocation; D060888:Real-Time Polymerase Chain Reaction; D051881:Receptor, Notch1 / Q000378:metabolism*; D000071656:Receptor, Notch3 / Q000378:metabolism*; D015398:Signal Transduction; D013997:Time Factors
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D000072100:Jagged-1 Protein; D008565:Membrane Proteins; D012333:RNA, Messenger; D051881:Receptor, Notch1; D000071656:Receptor, Notch3; C064045:delta protein
keywords: Bite force; Cartilage; Mandibular condyle; Notch pathway