Deleting Suppressor of Cytokine Signaling-3 in chondrocytes reduces bone growth by disrupting mitogen-activated protein kinase signaling

X Liu; A A D'Cruz; J Hansen; B A Croker; K E Lawlor; N A Sims; I P Wicks

doi:10.1016/j.joca.2019.05.018

Deleting Suppressor of Cytokine Signaling-3 in chondrocytes reduces bone growth by disrupting mitogen-activated protein kinase signaling

Osteoarthritis Cartilage. 2019 Oct;27(10):1557-1563. doi: 10.1016/j.joca.2019.05.018. Epub 2019 Jun 5.

Authors

X Liu¹, A A D'Cruz², J Hansen³, B A Croker⁴, K E Lawlor⁵, N A Sims⁶, I P Wicks⁷

Affiliations

¹ Inflammation Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, Victoria, 3010, Australia; University of Queensland, Diamantina Institute, Brisbane, Queensland, 4102, Australia.
² Inflammation Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, Victoria, 3010, Australia.
³ Inflammation Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia.
⁴ Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA, 02115, USA.
⁵ Inflammation Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, Victoria, 3010, Australia; Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, Victoria, 3168, Australia; Department of Molecular and Translational Science, Monash University, Clayton, Victoria, 3168, Australia.
⁶ St. Vincent's Institute of Medical Research, Fitzroy, Victoria, 3065, Australia; Department of Medicine at St Vincent's Hospital, The University of Melbourne, 3065, Australia.
⁷ Inflammation Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, Victoria, 3010, Australia; Rheumatology Unit, Royal Melbourne Hospital, Parkville, Victoria, 3050, Australia. Electronic address: wicks@wehi.edu.au.

PMID: 31176017
DOI: 10.1016/j.joca.2019.05.018

Abstract

Objective: To investigate the impact of deleting Suppressor of Cytokine Signaling (SOCS)-3 (SOCS3) in chondrocytes during murine skeletal development.

Method: Mice with a conditional Socs3 allele (Socs3^fl/fl) were crossed with a transgenic mouse expressing Cre recombinase under the control of the type II collagen promoter (Col2a1) to generate Socs3^Δ/Δcol2 mice. Skeletal growth was analyzed over the lifespan of Socs3^Δ/Δcol2 mice and controls by detailed histomorphology. Bone size and cortical bone development was evaluated by micro-computed tomography (micro-CT). Growth plate (GP) zone width, chondrocyte proliferation and apoptosis were assessed by immunofluorescence staining for Ki67 and TUNEL. Fibroblast growth factor receptor-3 (FGFR3) signaling in the GP was assessed by immunohistochemistry, while the effect of SOCS3 overexpression on FGFR3-driven pMAPK signaling in HEK293T cells was evaluated by Western blot.

Results: Socs3^Δ/Δcol2 mice of both sexes were consistently smaller compared to littermate controls throughout life. This phenotype was due to reduced long bone size, poor cortical bone development, reduced Ki67⁺ proliferative chondrocytes and decreased proliferative zone (PZ) width in the GP. Expression of pMAPK, but not pSTAT3, was increased in the GPs of Socs3^Δ/Δcol2 mice relative to littermate controls. Overexpression of FGFR3 in HEK293T cells increased Fibroblast Growth Factor 18 (FGF18)-dependent Mitogen-activated protein kinase (MAPK) phosphorylation, while concomitant expression of SOCS3 reduced FGFR3 expression and abrogated MAPK signaling.

Conclusion: Our results suggest a potential role for SOCS3 in GP chondrocyte proliferation by regulating FGFR3-dependent MAPK signaling in response to FGF18.

Keywords: Bone and skeleton; Cartilage; Chondrocytes.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Bone Development / physiology*
Chondrocytes / physiology*
Female
Male
Mice
Mice, Transgenic
Mitogen-Activated Protein Kinases / physiology*
Signal Transduction
Suppressor of Cytokine Signaling 1 Protein / physiology*

Substances

Socs1 protein, mouse
Suppressor of Cytokine Signaling 1 Protein
Mitogen-Activated Protein Kinases