The effects of different frequency treadmill exercise on lipoxin A4 and articular cartilage degeneration in an experimental model of monosodium iodoacetate-induced osteoarthritis in rats

• Published in: PloS one 2017-06, Vol.12 (6), p.e0179162-e0179162
• Main Authors: Yang, Yue, Wang, Yang, Kong, Yawei, Zhang, Xiaoning, Bai, Lunhao
• Format: Article
• Language: English
• Subjects: Animals; Anti-inflammatory agents; Arthritis; Biocompatibility; Biology and Life Sciences; Blotting, Western; Bone surgery; Cartilage; Cartilage (articular); Cartilage diseases; Cartilage, Articular - metabolism; Cartilage, Articular - pathology; Cytokines; Degeneration; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Evaluation; Exercise; Fitness equipment; Gene expression; Histology; Histopathology; Immunohistochemistry; Inflammation; Interleukin 1; Iodoacetates; Joints - pathology; Kinases; Knee; Lipoxin A4; Lipoxins - metabolism; Male; Matrix metalloproteinase; Medicine and Health Sciences; Metalloproteinase; NF-kappa B - metabolism; NF-κB protein; Orthopedics; Osteoarthritis; Osteoarthritis - blood; Osteoarthritis - chemically induced; Osteoarthritis - pathology; Physical Conditioning, Animal; Physical fitness; Physical training; Polymerase Chain Reaction; Rats; Rats, Sprague-Dawley; Real time; Research and Analysis Methods; Rodents; Running; Signal Transduction; Studies; Treadmills; Tumor necrosis factor; Western blotting
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0179162

The aim was to investigate the effects of different frequencies treadmill exercise with total exercise time being constancy on articular cartilage, lipoxin A4 (LXA4) and the NF-κB pathway in rat model of monosodium iodoacetate-induced osteoarthritis (OA). Fifty male Sprague-Dawley rats were randomly divided into five groups (n = 10): controls (CG), knee OA model (OAG), OA + treadmill exercise once daily (OAE1), OA + treadmill exercise twice daily, rest interval between exercise>4h (OAE2) and OA + treadmill exercise three times daily, rest interval between exercise>4h (OAE3). Rats were evaluated after completing the treadmill exercise program (speed, 18 m/min; total exercise time 60 min/day; 5 days/week for 8 weeks). Interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and LXA4 in serum and intra-articular lavage fluid were measured by ELISA. Changes in articular cartilage were evaluated by histology, immunohistochemistry, western blotting and quantitative real-time-PCR. LXA4 in the serum and intra-articular lavage fluid increased in all OAE groups, and histological evaluation indicated that the OAE3 group had the best treatment response. The expression of COL2A1 and IκB-β in articular cartilage increased in all OAE groups vs the OAG group, whereas expression of IL-1β, TNF-α, matrix metalloproteinase (MMP)-13, and NF-κB p65 was reduced in all OAE groups compared with the OAG. Under the condition of 60 min treadmill exercise with moderate-intensity, to fulfill in three times would have better chondroprotective effects than to fulfill in two or one time on monosodium iodoacetate-induced OA in rats. And it may be worked through the anti-inflammatory activity of LXA4 and the NF-κB pathway.