Anti-inflammatory effects of low intensity laser therapy on adjuvant-induced rheumatoid arthritis in rat

Abstract

[Purpose] The purpose of this study was to evaluate the anti-inflammatory and analgesic efficacy of low-intensity laser therapy (LILT) on adjuvant-induced arthritis in a rat model. [Subjects] Thirty Sprague-Dawley rats were randomly divided into 3 groups: normal, placebo, and LILT groups. The arthritis group was treated with low intensity laser therapy using a gallium-aluminum-arsenide diode laser device for 3 weeks. Each group had 10 rats. All treatments were applied once a day, 5 days a week, for a total experimental period of 21 days. The hind paw volume and articular index of the knee joint along with TNF-α and IL-6 levels in the serum were used as outcome measures. [Results] Hind paw volume and the arthritis index of rats in the placebo group were significantly higher than those in the normal group (p<0.05). In the laser treatment group, the hind paw volume, the arthritis index, and TNF-α and IL-6 concentrations were significantly decreased than those in the placebo group. [Conclusion] We concluded that LILT is effective at in alleviating RA symptoms such as edema, arthritic index, and the expression profiles of inflammation cytokines in adjuvant-induced arthritic rats.