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. 2017 Jul 28;18(1):320.
doi: 10.1186/s12891-017-1653-7.

GIT1 gene deletion delays chondrocyte differentiation and healing of tibial plateau fracture through suppressing proliferation and apoptosis of chondrocyte

Peng Chen  1 , Wan-Li Gu  1 , Ming-Zhi Gong  1 , Jun Wang  1 , Dong-Qing Li  2
Affiliations

GIT1 gene deletion delays chondrocyte differentiation and healing of tibial plateau fracture through suppressing proliferation and apoptosis of chondrocyte

Peng Chen et al. BMC Musculoskelet Disord. .

Abstract

Background: Although tibial plateau fracture is an uncommon injury, its regulation is challenging and there are some influencing factors, including the effects of severe bone displacement, depression and cancellous bone cartilage, and inevitable cartilage damage. And GIT1 plays an important role in bone mass and 78 osteoblast cell migration.

Methods: The study used 72 C57/BL6 mice. A tibial plateau fracture model was established by using mice with the same number of GIT1 gene deletions (the experimental group) and their wild-type littermates (the control group). Joint and bone callus recovery were evaluated by X-ray and CT thin layer scans. Micro CT assay and histomorphometry were conducted in order to evaluate the volume of newly formed blood vessels. Type II collagen expression in tibial tissues after tibial plateau fracture were detected by immunohistochemistry after 7, 14 and 21 days. The number of proliferating cell nuclear antigen (PCNA) positive cells after tibial plateau fracture was tested by immunohistochemistry after 14 and 21 days. The terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining was conducted after 14 and 21 days in order to test chondrocyte apoptosis in tibial tissues after tibial plateau fracture.

Results: The GIT1 gene deletion group mice spent less time on the rotating rod than the control group mice (P < 0.05). Compared with the control group, postoperative recovery was retarded, because GIT1 gene deletion slowed down neovascularization after tibial plateau fracture (P < 0.05). Compared with the control group, mouse type II collagen expression significantly decreased in the GIT1 gene deletion group, and the proportion of PCNA positive cells significantly decreased (P < 0.05). The TUNEL results indicate that GIT1 gene deletion led to reduced chondrocyte apoptosis.

Conclusion: GIT1 gene deletion can inhibit chondrocyte proliferation and apoptosis during the recovery of tibial plateau fracture, so as to delay chondrocyte differentiation and tibial plateau fracture healing.

Keywords: Apoptosis; GIT1; Gene deletion; Proliferation; Tibial plateau fracture.

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Conflict of interest statement

Ethics approval

The study was approved by the Ethics Committee of the Second Hospital of Shandong University. All procedures were in compliance with ethical guidelines for animal experiments. All efforts were made to minimize animal suffering.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests.

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Figures

Fig. 1
Fig. 1
The results of the rotarod test in the GIT1-WT and GIT1-KO group. Note: *, P < 0.05, compared with the control group
Fig. 2
Fig. 2
The results of CT thin layer scans of tibial plateau in the control and experiment groups on the 14th day after operation. Notes: *P < 0.05, compared with the control group; CT: Computed tomography
Fig. 3
Fig. 3
Effects of GIT1 gene deletion on neovascularization after tibial plateau fracture. Notes: a, volume statistics of new blood vessels; b, kinetic analysis of the blood vessels growth after operation; Cur1, modeling curve of statistical curve in the GIT1-WT group (coefficient 1.432); Cur2, modeling curve of statistical curve in the GIT1-KO group (coefficient 0.631); *, P < 0.05, compared with the control group
Fig. 4
Fig. 4
Comparisons of immunohistochemistry results of type II collagen in tibial tissues between the control and experimental groups. Notes: *, P < 0.05, compared with the control group
Fig. 5
Fig. 5
Comparison of immunohistochemistry results of PCNA staining in tibial tissues between the control and experimental groups. Notes: a immunohistochemistry results of PCNA staining in tibial tissues (×400); b the number of PCNA positive cells in each bone callus; *, P < 0.05, compared with the control group; PCNA: Proliferating cell nuclear antigen
Fig. 6
Fig. 6
Effects of GIT1 gene deletion on apoptosis of chondrocytes after tibial plateau fracture. Notes: a, b TUNEL staining result on the 14th day after surgery (×200); c d, DAPI staining result on the 14th day after surgery (×200); e, f TUNEL staining result on the 21st day after surgery (×200); g h, DAPI staining result on the 21st day after surgery (×200); i, The number of TUNEL positive cells (TUNEL positive cells/DAPI positive cells); *, P < 0.05, compared with the control group; DAPI: Diamidino-phenyl-indole; TUNEL: TDT-mediated dUTP-biotin nick end-labeling
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References

    1. Hsieh CH, Huang HT, Liu PC, Lu CC, Chen JC, Lin GT. Anterior approach for posteromedial tibial plateau fractures. Kaohsiung J Med Sci. 2010;26(3):130–135. doi: 10.1016/S1607-551X(10)70019-X. - DOI - PMC - PubMed
    1. Brunner A, Horisberger M, Ulmar B, Hoffmann A, Babst R. Classification systems for tibial plateau fractures; does computed tomography scanning improve their reliability? Injury. 2010;41(2):173–178. doi: 10.1016/j.injury.2009.08.016. - DOI - PubMed
    1. Manidakis N, Dosani A, Dimitriou R, Stengel D, Matthews S, Giannoudis P. Tibial plateau fractures: functional outcome and incidence of osteoarthritis in 125 cases. Int Orthop. 2010;34(4):565–570. doi: 10.1007/s00264-009-0790-5. - DOI - PMC - PubMed
    1. Biggi F, Di Fabio S, D'Antimo C, Trevisani S. Tibial plateau fractures: internal fixation with locking plates and the MIPO technique. Injury. 2010;41(11):1178–1182. doi: 10.1016/j.injury.2010.08.001. - DOI - PubMed
    1. Goff T, Kanakaris NK, Giannoudis PV. Use of bone graft substitutes in the management of tibial plateau fractures. Injury. 2013;44(Suppl 1):S86–S94. doi: 10.1016/S0020-1383(13)70019-6. - DOI - PubMed