Stimulation of enzyme and cytokine production by methyl mercaptan in human gingival fibroblast and monocyte cell cultures

Abstract

The volatile sulphur compound methyl mercaptan (CH 3SH) is a by-product of protein metabolism and a principal component of oral malodour. This investigation examines the effect of CH 3SH on the enzymatic activities of cathepsins B and G and elastase, and on the production by human gingival fibroblasts of two key factors, prostaglandin E (PGE) and cAMP, of the PGE 2-cAMP-dependent pathway, which may contribute to the increased production of collagenase and tissue destruction in human periodontal dnsease. The results demonstrate that CH 3SH alone, or in combination with interleukin-1 (IL-1) or lipopolysaccharide, can significantly enhance the secretion of PGE 2, cAMP and procollagenase by human gingival fibroblasts. CH 3SH also stimulated mononuclear cells to produce IL-1, which can increase cAMP production, and act in synergism with the direct effect of CH 3SH on cAMP. CH 3SH also significantly enhanced the activity of cathepsin B, moderately suppressed that of cathepsin G, but did not significantly affect elastase. These results provide evidence that CH 3SH could be a contributing factor in the enzymatic and immunological cascade of events leading to tissue degradation in periodontal diseases.