Complicated Effect of He-Ne Laser Therapy on Pro-/Anti-Inflammatory Cytokines from Serum in Rats

Abstract

Helium-neon (He-Ne) laser is one of the most common low energy lasers used in physiotherapy for promoting wound healing. This study was about to investigate the effects of He-Ne laser therapy on the pro-/anti-inflammatory cytokines in rats up to 10 days of treatment. 16 non-pregnant female rats were divided into 4 groups randomly, 4 rats in each group. They are negative control (NC) group, positive control (PC) group, laser treatment (LA) group and erythromycin ointment (ER) treatment group. The LA group was treated with 25 mW of He-Ne laser for 30 min every day for 10 days, with 632.8 nm of wavelength immediately after three incisions were made on the mid-dorsal line of each rat. The results showed that He-Ne laser therapy could decrease the level of IL-1β compared with the PC and ER groups; while increase the level of IL-6 compared with the NC and ER groups, and the level of TNF-α compared with the PC and ER group. He-Ne laser therapy also increased the concentration of IL-10 compared with the other three groups, and the concentration of TGF-β compared with the NC and ER groups. These results indicated that laser acupuncture increased the production of IL-6, IL-10, TGF-β and TNF-α after 10 days of treatment, which was the proliferation stage of wound healing process, and the effect of He-Ne laser therapy on pro-inflammatory cytokines was not always consistent, which might be time-dependent of He-Ne laser treatment.