S‐Nitrosoglutathione Decreases Inflammation and Bone Resorption in Experimental Periodontitis in Rats

Background: S‐nitrosoglutathione (GSNO) is a nitric oxide donor that may exert antioxidant, anti‐inflammatory, and microbicidal actions and is thus a potential drug for the topical treatment of periodontitis. In this study, the effect of intragingival injections of GSNO‐containing polyvinylpyrrolidone (PVP) formulations is evaluated in a rat model of periodontitis. Methods: Periodontal disease was induced by placing a sterilized nylon (000) thread ligature around the cervix of the second left upper molar of the animals, which received intragingival injections of PVP; saline; or PVP/GSNO solutions which corresponded to GSNO doses of 25, 100, and 500 nmol; 1 hour before periodontitis induction, and thereafter, daily for 11 days. Results: PVP/GSNO formulations at doses of 25 and/or 100, but not 500 nmol caused significant inhibition of alveolar bone loss, increase of bone alkaline phosphatase, decrease of myeloperoxidase activity, as well as significant reduction of inflammatory and oxidative stress markers when compared to saline and PVP groups. These effects were also associated with a decrease of matrix metalloproteinases 1 and 8, inducible nitric oxide synthase, and nuclear factor‐κB immunostaining in the periodontium. Conclusion: Local intragingival injections of GSNO reduces inflammation and bone loss in experimental periodontal disease.