Effects of low-level laser irradiation in cultured synovial cells from human TMJ

Abstract

Immediate effects of low-level laser irradiation (LLLI), such as anti-inflammation and pain relief of temporomandibular joint (TMJ) disorders, have been reported. However, the molecular based mechanisms have not been elucidated yet. Synovial cells are believed to play pathological roles in the development and continuation of inflammation. Chemokines, such as interleukin (IL) -8 and monocyte chemoattractant protein (MCP) -1, have been found in synovial fluid from patients with TMJ synovitis as well as IL-1β.
This study examined the effect of LLLI on the production of chemokines stimulated in human synovial cells treated with IL-1β. The cells were isolated from TMJ synovial tissues and cultured using the outgrowth method. The confluent-stage cells were treated with IL-1β at the same time as LLLI was performed on the cells. The amounts of chemokines in conditioned medium were measured by an ELISA kit.
LLLI significantly reduced the production of IL-8 and MCP-1 in the early stage. These findings suggest that LLLI may have an anti-inflammatory effect on TMJ disorders through the reduction of chemokines production.