E Mével1, J A Shutter2, X Ding3, B T Mattingly4, J N Williams5, Y Li6, A Huls7, A V Kambrath8, S B Trippel9, D Wagner10, M R Allen11, R O'Keefe12, W R Thompson13, D B Burr14, U Sankar15. 1. Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. Electronic address: elsa.mevel@hotmail.fr. 2. Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. Electronic address: jeshut@iu.edu. 3. Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. Electronic address: xinding@iu.edu. 4. Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. Electronic address: btmattin@iu.edu. 5. Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. Electronic address: jw225@iupui.edu. 6. Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. Electronic address: liyon@iu.edu. 7. Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. Electronic address: ahuls@iu.edu. 8. Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. Electronic address: anvaliya@iu.edu. 9. Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. Electronic address: strippel@iu.edu. 10. Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Department of Mechanical and Energy Engineering, School of Engineering and Technology, Indianapolis, IN, 46202, USA. Electronic address: wagnerdi@iupui.edu. 11. Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Department of Orthopaedic Surgery, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. Electronic address: matallen@iu.edu. 12. Department of Orthopaedic Surgery, Washington University School of Medicine, St. Louis, MO, 63110, USA. Electronic address: rokeefe@wustl.edu. 13. Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Department of Physical Therapy, School of Health and Rehabilitation Sciences, Indianapolis, IN, 46202, USA. Electronic address: thompwil@iu.ed. 14. Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. Electronic address: dburr@iu.edu. 15. Department of Anatomy, Cell Biology and Physiology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA; Indiana Center for Musculoskeletal Health, Indiana University School of Medicine, Indianapolis, IN, 46202, USA. Electronic address: usankar@iu.edu.
Abstract
OBJECTIVE: To investigate the role of Ca2+/calmodulin-dependent protein kinase 2 (CaMKK2) in post-traumatic osteoarthritis (PTOA). METHODS: Destabilization of the medial meniscus (DMM) or sham surgeries were performed on 10-week-old male wild-type (WT) and Camkk2-/- mice. Half of the DMM-WT mice and all other cohorts (n = 6/group) received tri-weekly intraperitoneal (i.p.) injections of saline whereas the remaining DMM-WT mice (n = 6/group) received i.p. injections of the CaMKK2 inhibitor STO-609 (0.033 mg/kg body weight) thrice a week. Study was terminated at 8- or 12-weeks post-surgery, and knee joints processed for microcomputed tomography imaging followed by histology and immunohistochemistry. Primary articular chondrocytes were isolated from knee joints of 4-6-day-old WT and Camkk2-/- mice, and treated with 10 ng/ml interleukin-1β (IL)-1β for 24 or 48 h to investigate gene and protein expression. RESULTS: CaMKK2 levels and activity became elevated in articular chondrocytes following IL-1β treatment or DMM surgery. Inhibition or absence of CaMKK2 protected against DMM-associated destruction of the cartilage, subchondral bone alterations and synovial inflammation. When challenged with IL-1β, chondrocytes lacking CaMKK2 displayed attenuated inflammation, cartilage catabolism, and resistance to suppression of matrix synthesis. IL-1β-treated CaMKK2-null chondrocytes displayed decreased IL-6 production, activation of signal transducer and activator of transcription 3 (Stat3) and matrix metalloproteinase 13 (MMP13), indicating a potential mechanism for the regulation of inflammatory responses in chondrocytes by CaMKK2. CONCLUSIONS: Our findings reveal a novel function for CaMKK2 in chondrocytes and highlight the potential for its inhibition as an innovative therapeutic strategy in the prevention of PTOA.
OBJECTIVE: To investigate the role of Ca2+/calmodulin-dependent protein kinase 2 (CaMKK2) in post-traumatic osteoarthritis (PTOA). METHODS: Destabilization of the medial meniscus (DMM) or sham surgeries were performed on 10-week-old male wild-type (WT) and Camkk2-/- mice. Half of the DMM-WT mice and all other cohorts (n = 6/group) received tri-weekly intraperitoneal (i.p.) injections of saline whereas the remaining DMM-WT mice (n = 6/group) received i.p. injections of the CaMKK2 inhibitor STO-609 (0.033 mg/kg body weight) thrice a week. Study was terminated at 8- or 12-weeks post-surgery, and knee joints processed for microcomputed tomography imaging followed by histology and immunohistochemistry. Primary articular chondrocytes were isolated from knee joints of 4-6-day-old WT and Camkk2-/- mice, and treated with 10 ng/ml interleukin-1β (IL)-1β for 24 or 48 h to investigate gene and protein expression. RESULTS: CaMKK2 levels and activity became elevated in articular chondrocytes following IL-1β treatment or DMM surgery. Inhibition or absence of CaMKK2 protected against DMM-associated destruction of the cartilage, subchondral bone alterations and synovial inflammation. When challenged with IL-1β, chondrocytes lacking CaMKK2 displayed attenuated inflammation, cartilage catabolism, and resistance to suppression of matrix synthesis. IL-1β-treated CaMKK2-null chondrocytes displayed decreased IL-6 production, activation of signal transducer and activator of transcription 3 (Stat3) and matrix metalloproteinase 13 (MMP13), indicating a potential mechanism for the regulation of inflammatory responses in chondrocytes by CaMKK2. CONCLUSIONS: Our findings reveal a novel function for CaMKK2 in chondrocytes and highlight the potential for its inhibition as an innovative therapeutic strategy in the prevention of PTOA.
Authors: Justin N Williams; Anuradha Valiya Kambrath; Roshni B Patel; Kyung Shin Kang; Elsa Mével; Yong Li; Ying-Hua Cheng; Austin J Pucylowski; Mariah A Hassert; Michael J Voor; Melissa A Kacena; William R Thompson; Stuart J Warden; David B Burr; Matthew R Allen; Alexander G Robling; Uma Sankar Journal: J Bone Miner Res Date: 2018-02-05 Impact factor: 6.390