MaquiBerry-Derived Cystatin and EGCG Synergize to Enhance Acquired Pellicle Viscoelasticity

Objectives: The acquired enamel pellicle (AEP) is one of the protective factors against dental caries and erosive tooth wear. In this context, within the scope of "AEP engineering," this study aimed to evaluate the effect of saliva enrichment with a new MaquiBerry-derived cystatin (0.5 mg/mL; MaquiCPI-3), a statherin-derived peptide (1.88x10^-5; StN15), or hemoglobin (1.0 mg/mL; Hb), either individually or in combination, with or without epigallocatechin gallate (1.25 mM; EGCG), on the thickness and viscoelastic properties of the AEP.
Methods: To achieve this, real-time analysis of the interaction between the proteins/peptides, with or without EGCG, and an unstimulated human saliva pool was performed using hydroxyapatite (HA) sensors to simulate tooth enamel, employing Quartz Crystal Microbalance with Dissipation Monitoring (QCM-D). The films formed on the HA sensors surface were subjected to rinsing with 1% citric acid at pH 3.6 to replicate extrinsic erosion conditions. The data were analyzed using the Dfind software, modeling physical properties with a viscoelastic Voigt-based model.
Results: Differences were observed in the frequency and dissipation profiles of the films adsorbed onto HA, highlighting the strong affinity of the proteins in conjunction with the polyphenol. Notably, saliva enriched with MaquiCPI-3 in combination with EGCG exhibited the strongest adhesion to HA, as demonstrated by the frequency differences between the adsorbed film (-576.41±0.06) and the rinse with citric acid (-501.69±0.01). Furthermore, combining proteins/peptides with EGCG resulted in increased AEP thickness in all groups. Our results reveal, for the first time, that saliva enriched with MaquiCPI-3 in combination with EGCG exhibited the highest viscosity (549.31±0.90 μ) and elasticity (16.44±0.001 k) compared to other groups.
Conclusions: These findings enhance our understanding of the protective mechanisms of AEP when enriched with proteins/peptides and polyphenols and propose a novel preventive strategy against erosive demineralization through AEP engineering techniques that could be integrated into future dental products.