Concluding Remarks
OA continues to be a challenging disease for rheumatologists and their patients. The direct impact of OA on a patient’s quality of life remains a significant problem, and reduced physical activity may increase the risk of conditions exacerbated by a sedentary lifestyle, such as cardiovascular disease.34,35
Without medical treatments to simultaneously mitigate their symptoms and prevent disease progression, OA patients often conclude, “Well, I guess there is nothing that can be done … until I’m ready for a new joint.” Although this is not entirely true, and many therapies, including pain modulators, physical therapy and injections, reduce suffering, transformative changes to the therapeutic landscape for OA patients have yet to be realized.
Our understanding of the pathogenesis of OA has increased over the past decade, and as we appreciate how OA affects the entire joint organ, we can begin to drill down on targets and pathways that may slow down or reverse the disease. Whether the promise of catabolic enzyme inhibitors, biolubricants or stem cell technologies will ever be realized in OA patients remains uncertain. However, I can tell my OA patients with confidence, “We’re still working on it.”
Antonios Aliprantis, MD, PhD, is director of the Brigham and Women’s Osteoarthritis Center, associate immunologist at Brigham and Women’s Hospital and assistant professor for Harvard Medical School, Boston.
References
- Little CB, Hunter DJ. Post-traumatic osteoarthritis: From mouse models to clinical trials. Nat Rev Rheumatol. 2013 Aug;9(8):485–497.
- Kannu P, Bateman JF, Randle S, et al. Premature arthritis is a distinct type II collagen phenotype. Arthritis Rheum. 2010 May;62(5):1421–1430.
- Bao JP, Chen WP, Wu LD. Lubricin: A novel potential biotherapeutic approaches for the treatment of osteoarthritis. Mol Biol Rep. 2011 Jun;38(5):2879–2885.
- Rhee DK, Marcelino J, Al-Mayouf S, et al. Consequences of disease-causing mutations on lubricin protein synthesis, secretion, and post-translational processing. J Biol Chem. 2005 Sep 2;280(35):31325–31332.
- Ritter SY, Subbaiah R, Bebek G, et al. Proteomic analysis of synovial fluid from the osteoarthritic knee: Comparison with transcriptome analyses of joint tissues. Arthritis Rheum. 2013 Apr;65(4):981–992.
- Li G, Yin J, Gao J, et al. Subchondral bone in osteoarthritis: Insight into risk factors and microstructural changes. Arthritis Res Ther. 2013;15(6):223.
- Jay GD, Waller KA. The biology of lubricin: Near frictionless joint motion. Matrix Biol. 2014 Oct;39:17–24.
- Miller RE, Lu Y, Tortorella MD, et al. Genetically engineered mouse models reveal the importance of proteases as osteoarthritis drug targets. Curr Rheumatol Rep. 2013 Aug;15(8):350.
- Glasson SS, Askew R, Sheppard B, et al. Deletion of active ADAMTS5 prevents cartilage degradation in a murine model of osteoarthritis. Nature. 2005 Mar 31(7033);434:644–648.
- Majumdar MK, Askew R, Schelling S, et al. Double-knockout of ADAMTS-4 and ADAMTS-5 in mice results in physiologically normal animals and prevents the progression of osteoarthritis. Arthritis Rheum. 2007 Nov;56(11):3670–3674.
- Little CB, Barai A, Burkhardt D, et al. Matrix metalloproteinase 13-deficient mice are resistant to osteoarthritic cartilage erosion but not chondrocyte hypertrophy or osteophyte development. Arthritis Rheum. 2009 Dec;60(12):3723–3733.
- Hayami T, Zhuo Y, Wesolowski GA, et al. Inhibition of cathepsin K reduces cartilage degeneration in the anterior cruciate ligament transection rabbit and murine models of osteoarthritis. Bone. 2012 Jun;50(6):1250–1259.
- Chen P, Zhu S, Wang Y, et al. The amelioration of cartilage degeneration by ADAMTS-5 inhibitor delivered in a hyaluronic acid hydrogel. Biomaterials. 2014 Mar;35(9):2827–2836.
- Wang M, Sampson ER, Jin H, et al. MMP13 is a critical target gene during the progression of osteoarthritis. Arthritis Res Ther. 2013 Jan 8;15(1):R5.
- Connor JR, LePage C, Swift BA, et al. Protective effects of a cathepsin K inhibitor, SB-553484, in the canine partial medial meniscectomy model of osteoarthritis. Osteoarthritis Cartilage. 2009 Sep;17(9):1236–1243.
- Kim JH, Jeon J, Shin M, et al. Regulation of the catabolic cascade in osteoarthritis by the zinc-ZIP8-MTF1 axis. Cell. 2014 Feb 13;156(4):730–743.
- Daniel M. Boundary cartilage lubrication: Review of current concepts. Wien Med Wochenschr. 2014 Mar;164(5–6):88–94.
- Rhee DK, Marcelino J, Baker M, et al. The secreted glycoprotein lubricin protects cartilage surfaces and inhibits synovial cell overgrowth. J Clin Invest. 2005 Mar;115(3):622–631.
- Flannery CR, Zollner R, Corcoran C, et al. Prevention of cartilage degeneration in a rat model of osteoarthritis by intraarticular treatment with recombinant lubricin. Arthritis Rheum. 2009 Mar;60(3):840–847.
- Jay GD, Fleming BC, Watkins BA, et al. Prevention of cartilage degeneration and restoration of chondroprotection by lubricin tribosupplementation in the rat following anterior cruciate ligament transection. Arthritis Rheum. 2010 Aug;62(8):2382–2391.
- Jay GD, Elsaid KA, Kelly KA, et al. Prevention of cartilage degeneration and gait asymmetry by lubricin tribosupplementation in the rat following anterior cruciate ligament transection. Arthritis Rheum. 2012 Apr;64(4):1162–1171.
- Teeple E, Elsaid KA, Jay GD, et al. Effects of supplemental intra-articular lubricin and hyaluronic acid on the progression of posttraumatic arthritis in the anterior cruciate ligament-deficient rat knee. A J Sports Med. 2011 Jan;39(1):164–172.
- Ruan MZ, Erez A, Guse K, et al. Proteoglycan 4 expression protects against the development of osteoarthritis. Sci Transl Med. 2013 Mar 13;5(176):176ra134.
- Makris EA, Gomoll AH, Malizos KN, et al. Repair and tissue engineering techniques for articular cartilage. Nat Rev Rheumatol. 2015 Jan;11(1):21–34.
- Kristjansson B, Honsawek S. Current perspectives in mesenchymal stem cell therapies for osteoarthritis. Stem Cells Int. 2014;2014:194318.
- Ankrum JA, Ong JF, Karp JM. Mesenchymal stem cells: Immune evasive, not immune privileged. Nat Biotechnol. 2014 Mar;32(3):252–260.
- Griffin MD, Ryan AE, Alagesan S, et al. Anti-donor immune responses elicited by allogeneic mesenchymal stem cells: What have we learned so far? Immunol Cell Biol. 2013 Jan;91(1):40–51.
- Wong KL, Lee KB, Tai BC, et al. Injectable cultured bone marrow-derived mesenchymal stem cells in varus knees with cartilage defects undergoing high tibial osteotomy: A prospective, randomized controlled clinical trial with 2 years’ follow-up. Arthroscopy. 2013 Dec;29(12):2020–2028.
- Vangsness CT Jr., Farr J 2nd, Boyd J, et al. Adult human mesenchymal stem cells delivered via intra-articular injection to the knee following partial medial meniscectomy: A randomized, double-blind, controlled study. J Bone Joint Surg Am. 2014 Jan 15;96(2):90–98.
- Willard VP, Diekman BO, Sanchez-Adams J, et al. Use of cartilage derived from murine induced pluripotent stem cells for osteoarthritis drug screening. Arthritis Rheumatol. 2014 Nov;66(11):3062–3072.
- Jiang Y, Tuan RS. Origin and function of cartilage stem/progenitor cells in osteoarthritis. Nat Rev Rheumatol. 2014 Dec 23;doi: 10.1038/nrrheum.2014.200 [Epub ahead of print].
- Johnson K, Zhu S, Tremblay MS, et al. A stem cell-based approach to cartilage repair. Science. 2012 May 11;336(6082):717–721.
- Kang ML, Ko JY, Kim JE, et al. Intra-articular delivery of kartogenin-conjugated chitosan nano/microparticles for cartilage regeneration. Biomaterials. 2014 Dec;35(37):9984–9994.
- Hawker GA, Croxford R, Bierman AS, et al. All-cause mortality and serious cardiovascular events in people with hip and knee osteoarthritis: A population based cohort study. PLoS One. 2014 Mar 7;9(3):e91286.
- Ravi B, Croxford R, Austin PC, et al. The relation between total joint arthroplasty and risk for serious cardiovascular events in patients with moderate-severe osteoarthritis: Propensity score matched landmark analysis. Br J Sports Med. 2014 Nov;48(21):1580.