STIMULATION OF ENZYME AND CYTOKINE PRODUCTION BY METHYL MERCAPTAN IN HUMAN GINGIVAL FIBROBLAST AND MONOCYTE CELL-CULTURES

The volatile sulphur compound methyl mercaptan (CH3SH) is a by-product of protein metabolism and a principal component of oral malodour. Thi s investigation examines the effect of CH3SH on the enzymatic activiti es of cathepsins B and G and elastase, and on the production by human gingival fibroblasts of two key factors, prostaglandin E (PGE) and cAM P, of the PGE(2)-cAMP-dependent pathway, which may contribute to the i ncreased production of collagenase and tissue destruction in human per iodontal disease. The results demonstrate that CH3SH alone, or in comb ination with interleukin-1 (IL-1) or lipopolysaccharide, can significa ntly enhance the secretion of PGE(2), cAMP and procollagenase by human gingival fibroblasts. CH3SH also stimulated mononuclear cells to prod uce IL-1, which can increase cAMP production, and act in synergism wit h the direct effect of CH3SH on cAMP. CH3SH also significantly enhance d the activity of cathepsin B, moderately suppressed that of cathepsin G, but did not significantly affect elastase. These results provide e vidence that CH3SH could be a contributing factor in the enzymatic and immunological cascade of events leading to tissue degradation in peri odontal diseases.