To observe the effect of fire-needle intervention on serum IL-1 and TNF-alpha contents in rheumatoid arthritis (RA) rats so as to study its underlying mechanism in improving RA.
A total of 40 Wistar rats were randomized into normal control, model, methotrexate (MTX, medication) group and fire-needle groups, with 10 cases in each group. RA model was established by injecting Freund's complete adjuvant (0.1 mL) into the rats' right hind paw. Fire-needle was applied to "Jiaji" (EX-B 2),"Zusanli" (ST 36) and "Ashi point" (the most severe site of the swelling joint), once every three days and 8 times altogether. The rat's right hindpaw swelling volume was detected by volumetric method, and serum IL-1 and TNF-alpha contents were determined by double antibody sandwich ELISA. The pathological changes of synovium tissue of the right knee-joint were observed by optical microscope.
In comparison with the control group, the swollen paw volumes at time-points of 12 d, 19 d, 26 d and 33 d after modeling and serum IL-1 and TNF-alpha contents were increased significantly (P < 0.01). Compared to the model group, the swollen paw volumes on day 33 in both medication and fire-needle groups were decreased considerably (P < 0.01), while serum IL-1 and TNF-alpha contents in the medication and fire-needle groups were reduced significantly (P < 0.05, P < 0.01). No significant differences were found between the medication and fire-needle groups in the swollen paw volumes on day 12 (P > 0.05). The pathological states (synovial cells' arrangement, inflammatory infiltration, synovial membrane thickening, etc.) of synovium tissue of the right knee-joint in both medication and fire-needle groups were relatively lighter than those of the model group.
Fire-needle therapy can down-regulate serum IL-1 and TNF-alpha contents in rheumatoid arthritis rats, and reduce the degree of arthroncus of the affected joint, which may contribute to its effect in improving synovial lesions.