Pro-inflammatory Cytokines Levels in saliva/serum of TMJ pain patients

Objective: Cytokines can modulate the host response to infection, injury, inflammation, and bone remodeling.  Plasma levels of pro-inflammatory cytokines have been correlated with TMJ bone loss and progression of disease in patients with TMJ rheumatoid arthritis. Thus, identification of cytokine profiles in sera and saliva that have a high correlation with symptoms may provide new targets for treating patients diagnosed with TMJD.

Methods: The levels of selected cytokines from saliva and serum were measured in 34 male and female patients with or without TMJD from different age groups. Multiple cytokines of interest were measured using microsphere sets coupled with specific capture antibodies and subjected to multianalyte profiling.

Results: Salivary levels of IL-1b were significantly higher in TMJD patients compared to a non-TMJD healthy controls (979.6 vs. 330.7 pg/ml) as were those for IL-6 (20.3 vs 2.3 pg/ml), with no significant differences seen in serum levels.  For levels of IL-8 and TNFa,  no significant differences were noted in saliva, but higher levels within the sera were seen in TMJD patients for IL-8 (174.2 vs. 25.8 pg/ml) and for TNFa (9.3 vs. 3.0 pg/ml), particularly in female TMJD patients in the 45-65 year old group who showed a 4- to 7-fold increase in these two pro-inflammatory cytokines compared to male and female control groups or male TMJD patients.  In examining levels of the anti-inflammatory cytokine IL-4, salivary levels were similar between TMJD and control patients, but sera levels of IL-4 were only detectable in male control patients.

Conclusions: Cytokine levels in TMJD can be altered in serum and saliva from patients with TMJ pain.  The role of pro-inflammatory and anti-inflammatory cytokines need to be further evaluated to document their sensitivity and specificity in distinguishing TMJD with and without co-morbid conditions from symptomatic TMJD subtypes as well as from non-TMJD controls. Supported by NIDCR/N01-DE-22635.