Alteration of cyclic nucleotides levels and oxidative stress in saliva of human subjects with periodontitis.

Experimental findings suggest a protective role for cyclic nucleotides against induction of oxidative stress in saliva. Oxidative stress is a major contributor to the pathogenesis of inflammatory diseases. This study was conducted to evaluate salivary oxidative stress along with cGMP and cAMP levels in periodontitis subjects. cAMP and cGMP are second messengers that have important roles in salivary gland functions. Unstimulated whole saliva samples were obtained from periodontitis patients and age- and sex-matched healthy individuals. Saliva samples were analyzed for thiobarbituric reactive substances (TBARS) as a marker of lipid peroxidation, ferric reducing ability (total antioxidant power, TAP), and levels of cAMP and cGMP. Concentrations of cAMP and cGMP were reduced in the saliva of patients with moderate and severe periodontitis. Saliva of patients with severe periodontitis had higher TBARS and lower TAP than control subjects. The presence of oxidative stress and lower levels of salivary cGMP and cAMP in periodontitis are in association with disease severity.