Dongmei Wang1, Hongxu Yang2, Mian Zhang2, Hongyun Zhang2, Lei Lu2, Jing Zhang2, Xianghong Wan3, Meiqing Wang4. 1. Department of Oral Medicine, School of Stomatology, Xinxiang Medical University, Xinxiang, China. 2. State Key Laboratory of Military Stomatology, Department of Oral Anatomy and Physiology and TMD, School of Stomatology, The Fourth Military Medical University, Xi'an, China. 3. Department of Oral Medicine, School of Stomatology, Xinxiang Medical University, Xinxiang, China; State Key Laboratory of Military Stomatology, Department of Oral Anatomy and Physiology and TMD, School of Stomatology, The Fourth Military Medical University, Xi'an, China. 4. State Key Laboratory of Military Stomatology, Department of Oral Anatomy and Physiology and TMD, School of Stomatology, The Fourth Military Medical University, Xi'an, China. Electronic address: mqwang@fmmu.edu.cn.
Abstract
OBJECTIVE: To investigate the changes in insulin-like growth factor-1 (IGF-1) expression levels in the degenerative mandibular condylar cartilage. DESIGN: Thirty-six rats were divided into the unilateral anterior crossbite and control groups. The expression levels of IGF-1; IGF-1 receptor (IGF-1R); IGF-binding protein-3 and -5 (IGFBP-3 and -5); proliferating cell nuclear antigen (PCNA); aggrecan; type-I, -II, -VI, and -X collagen; tissue inhibitor of metalloproteinases-1 and -3 (TIMP-1 and -3); metalloproteinases of matrix metalloproteinases-3 and-13 (MMP-3 and -13); a disintegrin and metalloproteinase thrombospondin-4 and -5 (ADAMTS-4 and -5); alkaline phosphatase (ALP); β-glucuronidase; and N-acetyl-β-glucosaminidase in the mandibular condylar cartilage were assessed. RESULTS: The protein expression levels of IGF-1and IGF-1R were increased from week 4 in the unilateral anterior crossbite group. The mRNA expression level of IGFBP-3 and -5 was upregulated from week 4 and week 2, respectively; that of IGFBP-3 was downregulated at week 8; and that of PCNA, type-II collagen, type-X collagen, aggrecan, TIMP-1, and TIMP-3 was downregulated, whereas that of MMP-3, MMP-13, ADAMTS-4, ADAMTS-5, β-glucuronidase, and N-acetyl-β-glucosaminidase were upregulated from week 2. The positive area size of type-I collagen was increased and that of type VI collagen was decreased from week 2. The positive area size of type X collagen was increased at week 2 but decreased at week 8. The percentage of ALP-positive cells was increased from week 4. CONCLUSIONS: Unilateral anterior crossbite stimulated the multifarious expression of IGF-1 and IGFBP, which may be linked to chondrocyte proliferation and differentiation in the mandibular condylar cartilage that showed progressive degeneration.
OBJECTIVE: To investigate the changes in insulin-like growth factor-1 (IGF-1) expression levels in the degenerative mandibular condylar cartilage. DESIGN: Thirty-six rats were divided into the unilateral anterior crossbite and control groups. The expression levels of IGF-1; IGF-1 receptor (IGF-1R); IGF-binding protein-3 and -5 (IGFBP-3 and -5); proliferating cell nuclear antigen (PCNA); aggrecan; type-I, -II, -VI, and -X collagen; tissue inhibitor of metalloproteinases-1 and -3 (TIMP-1 and -3); metalloproteinases of matrix metalloproteinases-3 and-13 (MMP-3 and -13); a disintegrin and metalloproteinase thrombospondin-4 and -5 (ADAMTS-4 and -5); alkaline phosphatase (ALP); β-glucuronidase; and N-acetyl-β-glucosaminidase in the mandibular condylar cartilage were assessed. RESULTS: The protein expression levels of IGF-1and IGF-1R were increased from week 4 in the unilateral anterior crossbite group. The mRNA expression level of IGFBP-3 and -5 was upregulated from week 4 and week 2, respectively; that of IGFBP-3 was downregulated at week 8; and that of PCNA, type-II collagen, type-X collagen, aggrecan, TIMP-1, and TIMP-3 was downregulated, whereas that of MMP-3, MMP-13, ADAMTS-4, ADAMTS-5, β-glucuronidase, and N-acetyl-β-glucosaminidase were upregulated from week 2. The positive area size of type-I collagen was increased and that of type VI collagen was decreased from week 2. The positive area size of type X collagen was increased at week 2 but decreased at week 8. The percentage of ALP-positive cells was increased from week 4. CONCLUSIONS: Unilateral anterior crossbite stimulated the multifarious expression of IGF-1 and IGFBP, which may be linked to chondrocyte proliferation and differentiation in the mandibular condylar cartilage that showed progressive degeneration.