IADR Abstract Archives
Endotoxin Deactivation: A New Quantifiable Determinant for Periodontal Chemotherapeutics.
Objectives: Lipopolysaccharides (LPS, also known as endotoxins) from select Gram-negative bacteria are directly associated with gingivitis and periodontitis. We have shown that TLR assays can be used to assess the virulence of bacterial strains and have demonstrated their application in the assessment of toxicity of clinical plaque samples. This study examined the potential for a variety of clinically proven antimicrobials stannous fluoride (SnF2), cetylpyridinium chloride (CPC) and triclosan to deactivate LPS virulence in vitro.
Methods: LPS deactivation potential was evaluated in two assays: (1) BODIPY TR cadaverine (BC) displacement assay (BCDA), and (2) Chromogenic Endotoxin Quantitation Kit. BC was used to measure the direct binding of SnF2, CPC and triclosan to LPS (Wood et al. Comb Chem High Throughput Screen 2004 7: 239–49). BC loses its fluorescence upon binding to LPS. Displacement of LPS restores BC fluorescence. Solutions of SnF2, CPC and triclosan were prepared at 0.625-2.5mM and applied to BCDA in the presence of 15ug/ml E. coli K12 LPS. Chromogenic Endotoxin Quantitation Kit (ThermoFisher) was used to determine the inhibitory effect of SnF2, CPC and triclosan on factor C activation by LPS.
Results: BCDA results strongly differentiated activities of clinically proven ingredients with % restoration of fluorescence at 2.5 mMol: SnF2 34 %; CPC 100 %; Triclosan: -2.5%. Chromogenic Endotoxin Quantitation assay likewise demonstrated that SnF2, CPC and Triclosan inhibited factor C activation by 92%, 100% and 1%, respectively.
Conclusions: SnF2 and CPC – both cationic antimicrobials – exhibited efficacy in binding to endotoxins, thereby leading to preventing endotoxins from activation of factor C. These results support a complementary and potentially important mechanism of oral therapeutics: direct detoxification of plaque through endotoxin binding.
Methods: LPS deactivation potential was evaluated in two assays: (1) BODIPY TR cadaverine (BC) displacement assay (BCDA), and (2) Chromogenic Endotoxin Quantitation Kit. BC was used to measure the direct binding of SnF2, CPC and triclosan to LPS (Wood et al. Comb Chem High Throughput Screen 2004 7: 239–49). BC loses its fluorescence upon binding to LPS. Displacement of LPS restores BC fluorescence. Solutions of SnF2, CPC and triclosan were prepared at 0.625-2.5mM and applied to BCDA in the presence of 15ug/ml E. coli K12 LPS. Chromogenic Endotoxin Quantitation Kit (ThermoFisher) was used to determine the inhibitory effect of SnF2, CPC and triclosan on factor C activation by LPS.
Results: BCDA results strongly differentiated activities of clinically proven ingredients with % restoration of fluorescence at 2.5 mMol: SnF2 34 %; CPC 100 %; Triclosan: -2.5%. Chromogenic Endotoxin Quantitation assay likewise demonstrated that SnF2, CPC and Triclosan inhibited factor C activation by 92%, 100% and 1%, respectively.
Conclusions: SnF2 and CPC – both cationic antimicrobials – exhibited efficacy in binding to endotoxins, thereby leading to preventing endotoxins from activation of factor C. These results support a complementary and potentially important mechanism of oral therapeutics: direct detoxification of plaque through endotoxin binding.