目的:本研究旨在驗證關節內注射A型肉毒桿菌素於大鼠膝部退化性關節炎的軟骨保護機制。設計: 於第0周以手術方式形成大鼠膝部退化性關節炎的動物模式，於術後滿4周時於右膝關節注射A型肉毒桿菌素，或是生理食鹽水(對照組)，並於術後滿8週及12週以切片比較膝關節軟骨磨損程度，並以軟骨細胞ATDC5 細胞對於施予A型肉毒桿菌素素或是生理食鹽水刺激之反應變化來研究其作用的訊息路徑。
結果:大鼠膝關節炎模式中，切片顯示注射肉毒桿菌素的膝關節軟骨磨損程度比對照組輕微，術後8周膝軟骨切片Mankin scale: A型肉毒桿菌素組為6.00±5.71，生理食鹽水組為9.13±6.13, 每組8隻, p=0.018，術後12周膝軟骨切片Mankin scale: A型肉毒桿菌素組為5.50±2.70，生理食鹽水組為8.83±2.97，每組6隻，p=0.008；軟骨細胞實驗顯示於培養21天的ATDC5 細胞，肉毒桿菌素降低ROCK1，ROCK 2以及type X collagen.
結論: 大鼠膝關節炎模式中，關節內注射BTXA應有軟骨保護的作用，與rho-signaling pathway有關。

Objective: This study aims to investigate the chondroprotective effect of botulinum toxin type A (BTXA) in rat knee osteoarthritis (OA) on histopathological severity and possible signaling pathway.
Design: Thirty-two rats with OA model established at week 0, received intraarticular (IA) injection of BTXA at week 4 in the experimental groups (n=16), while normal saline in the control groups (n=16). Within each group, rats were sacrificed at 8 weeks (n=8) and at 12 weeks (n=8). Cartilage degradation based on Mankin scale was evaluated. ATDC5 chondrocyte cells treated without and with BTXA were analyzed for real-time polymerase chain reaction (RT-PCR) for Type X collagen, rho-associated, coiled-coil-containing protein kinase 1 (ROCK I) & ROCK II level.
Results: Rat knee OA study revealed significantly lower Mankin scale in the experimental groups than in the control groups after both 8 weeks (BTXA vs. control: 6.00±5.71 vs. 9.13±6.13, n=8 in each group, p=0.018) and 12 weeks (5.50±2.70 vs. 8.83±2.97, n=6 in each group, p=0.008), respectively. In ATDC5 chondrocyte cell culture, the expression of ROCK I and II and type X collagen decreased after addition of BTXA, in comparison to control, based on RT-PCR.
Conclusion: Intraarticular injection of BTXA provides chondroprotective effect in rat knee OA model, possibly via rho signaling pathway.

1. Peat G, McCarney R, Croft P. Knee pain and osteoarthritis in older adults: a review of community burden and current use of primary health care. Annals of the rheumatic diseases. 2001;60(2):91-97.
2. Gur H, Cakin N. Muscle mass, isokinetic torque, and functional capacity in women with osteoarthritis of the knee. Archives of physical medicine and rehabilitation. 2003;84(10):1534-1541.
3. Kolasinski SL, Neogi T, Hochberg MC, et al. 2019 American College of Rheumatology/Arthritis Foundation Guideline for the Management of Osteoarthritis of the Hand, Hip, and Knee. Arthritis Rheumatol. 2020;72(2):220-233.
4. Bannuru RR, Schmid CH, Kent DM, Vaysbrot EE, Wong JB, McAlindon TE. Comparative effectiveness of pharmacologic interventions for knee osteoarthritis: a systematic review and network meta-analysis. Ann Intern Med. 2015;162(1):46-54.
5. Jones IA, Togashi R, Wilson ML, Heckmann N, Vangsness CT, Jr. Intra-articular treatment options for knee osteoarthritis. Nat Rev Rheumatol. 2019;15(2):77-90.
6. Kao I, Drachman DB, Price DL. Botulinum toxin: mechanism of presynaptic blockade. Science. 1976;193(4259):1256-1258.
7. Jankovic J, Brin MF. Therapeutic uses of botulinum toxin. The New England journal of medicine. 1991;324(17):1186-1194.
8. Wong V. Use of botulinum toxin injection in 17 children with spastic cerebral palsy. Pediatric neurology. 1998;18(2):124-131.
9. Silberstein S, Mathew N, Saper J, Jenkins S. Botulinum toxin type A as a migraine preventive treatment. For the BOTOX Migraine Clinical Research Group. Headache. 2000;40(6):445-450.
10. Desai MJ, Shkolnikova T, Nava A, Inwald D. A critical appraisal of the evidence for botulinum toxin type A in the treatment for cervico-thoracic myofascial pain syndrome. Pain Pract. 2014;14(2):185-195.
11. Mittal SO, Safarpour D, Jabbari B. Botulinum Toxin Treatment of Neuropathic Pain. Semin Neurol. 2016;36(1):73-83.
12. Chou CL, Lee SH, Lu SY, Tsai KL, Ho CY, Lai HC. Therapeutic effects of intra-articular botulinum neurotoxin in advanced knee osteoarthritis. J Chin Med Assoc. 2010;73(11):573-580.
13. Kalichman L, Bannuru RR, Severin M, Harvey W. Injection of botulinum toxin for treatment of chronic lateral epicondylitis: systematic review and meta-analysis. Semin Arthritis Rheum. 2011;40(6):532-538.
14. Namazi H. Botulinum toxin as a novel addition to anti-arthritis armamentarium: an experimental study in rabbits. Int Immunopharmacol. 2006;6(11):1743-1747.
15. Ismiarto YD, Prasetiyo GT. Efficacy and Safety of Intra-Articular Botulinum Toxin A Injection for Knee Osteoarthritis: A Systematic Review, Meta-Analysis, and Meta-Regression of Clinical Trials. JB JS Open Access. 2023;8(1).
16. Woods A, Wang G, Beier F. RhoA/ROCK signaling regulates Sox9 expression and actin organization during chondrogenesis. The Journal of biological chemistry. 2005;280(12):11626-11634.
17. Takeshita N, Yoshimi E, Hatori C, Kumakura F, Seki N, Shimizu Y. Alleviating effects of AS1892802, a Rho kinase inhibitor, on osteoarthritic disorders in rodents. J Pharmacol Sci. 2011;115(4):481-489.
18. Mankin HJ, Dorfman H, Lippiello L, Zarins A. Biochemical and metabolic abnormalities in articular cartilage from osteo-arthritic human hips. II. Correlation of morphology with biochemical and metabolic data. The Journal of bone and joint surgery American volume. 1971;53(3):523-537.
19. Yoo KY, Lee HS, Cho YK, et al. Anti-inflammatory effects of botulinum toxin type a in a complete Freund's adjuvant-induced arthritic knee joint of hind leg on rat model. Neurotox Res. 2014;26(1):32-39.
20. Mahowald ML, Krug HE, Singh JA, Dykstra D. Intra-articular Botulinum Toxin Type A: a new approach to treat arthritis joint pain. Toxicon. 2009;54(5):658-667.
21. Charlier E, Deroyer C, Ciregia F, et al. Chondrocyte dedifferentiation and osteoarthritis (OA). Biochem Pharmacol. 2019;165:49-65.
22. Furumatsu T, Matsumoto-Ogawa E, Tanaka T, Lu Z, Ozaki T. ROCK inhibition enhances aggrecan deposition and suppresses matrix metalloproteinase-3 production in human articular chondrocytes. Connective tissue research. 2014;55(2):89-95.
23. Piltti J, Bygdell J, Fernandez-Echevarria C, Marcellino D, Lammi MJ. Rho-kinase inhibitor Y-27632 and hypoxia synergistically enhance chondrocytic phenotype and modify S100 protein profiles in human chondrosarcoma cells. Sci Rep. 2017;7(1):3708.
24. Egloff C, Hart DA, Hewitt C, Vavken P, Valderrabano V, Herzog W. Joint instability leads to long-term alterations to knee synovium and osteoarthritis in a rabbit model. Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society. 2016;24(6):1054-1060.
25. Singh JA, Noorbaloochi S, Knutson KL. Cytokine and neuropeptide levels are associated with pain relief in patients with chronically painful total knee arthroplasty: a pilot study. BMC Musculoskelet Disord. 2017;18(1):17.