Effects of Aerobic Exercise and Stem Cell Injection on the Expression of NF-κB and MMP1 Genes in the Knee Cartilage of Male Rat Models of Osteoarthritis

Background and Aim: Regular aerobic exercise and stem cell therapy have shown promising effects in the management of osteoarthritis. The increased expression of nuclear factor kappa B (NF-κB) plays a significant role in joint degradation in osteoarthritis, while matrix metalloproteinase-1 (MMP1) gene expression is elevated in the joint bones of osteoarthritis patients. This study aimed to investigate the effects of aerobic exercise and stem cell injection on the expression of NF-κB and MMP1 genes in the knee cartilage of male rat models of osteoarthritis. Methods: In this experimental study, 25 male rats were randomly assigned to five groups: healthy control, osteoarthritis-induced (diseased), diseased + exercise, diseased + stem cells, and diseased + exercise + stem cells. The exercise program included 30 minutes of treadmill running at 16 meters per minute during the first week, gradually increasing to 50 minutes by the eighth week, following the principle of progressive overload. Mesenchymal stem cells were administered to the relevant groups at a dose of 1×10^6 cells per kilogram via a single injection. Forty-eight hours after the final exercise session, knee cartilage tissue was extracted, and the expression of NF-κB and MMP1 genes was evaluated using Real-Time PCR. Results: The expression of NF-κB in the osteoarthritis group was significantly higher than in the healthy control group (P=0.001). Aerobic exercise resulted in a significant reduction in NF-κB expression compared to the diseased group (P=0.043). However, stem cell treatment alone did not significantly affect the reduction of this gene expression (P=0.077). Additionally, no significant differences were found in MMP1 gene expression between the study groups (P>0.05), although the pattern of changes mirrored those observed in NF-κB expression. Conclusion: While stem cell therapy alone did not show a significant effect on gene expression modulation, regular aerobic exercise significantly reduced NF-κB expression. These findings support the potential of aerobic exercise as an effective intervention to suppress NF-κB in the management of osteoarthritis.