Phenolic Compounds of Reynoutria sp. as Modulators of Oral Cavity Lactoperoxidase System

Abstract

Lactoperoxidase (LPO) together with its (pseudo)halogenation cycle substrates, H2O2 and thiocyanate ions oxidized to hypothiocyanite ions, form one of the main systems involved in antimicrobial defense within the oral cavity. In bacterial diseases such as dental caries, lactoperoxidase is oxidized to a form known as Compound II, which is characterized by its inability to oxidize SCN–, resulting in a decreased generation of antimicrobial products. Reynoutria sp. rizome extracts, due to their high polyphenol content, have been tested as a source of compounds able to regenerate the antimicrobial activity of lactoperoxidase through converting the Compound II to the native LPO state. In the presented study, acetone extracts of R. japonica, R. sachalinensis, and R. x bohemica, together with their five fractions and four selected polyphenols dominating in the studied in extracts, were tested toward lactoperoxidase reactivating potential. For this purpose, IC50, EC50, and activation percentage were determined by Ellman’s method. Furthermore, the rate constants for the conversion of Compound I–Compound II and Compound II–native-LPO in the presence of extracts, extracts fractions, and selected polyphenols were determined. Finally, the ability to enhance the antimicrobial properties of the lactoperoxidase system was tested against Streptococcus mutans. We proved that Reynoutria sp. rhizome is the source of lactoperoxidase peroxidation cycle substrates, which can act as activators and inhibitors of the antimicrobial properties of that system. The presented study shows that the reactivation of lactoperoxidase could become a potential therapeutic target in prevention and treatment support in some infectious oral diseases.

Polyphenols in Oral Health: Homeostasis Maintenance, Disease Prevention, and Therapeutic Applications

“…Numerous studies have shown that polyphenols exhibit antibacterial activity against the S. mutans (Figure 2, Table 2) [8,[41][42][43]. Babaeekhou and Ghane demonstrated that extracts of ginger have high antibacterial activity against S. mutans and S. sobrinus [44].…”

New Approaches on Japanese Knotweed (Fallopia japonica) Bioactive Compounds and Their Potential of Pharmacological and Beekeeping Activities: Challenges and Future Directions

“…Recently, it became the spotlight of numerous studies, since its chemical composition has revealed promising therapeutic effects. Alcoholic, hydroalcoholic and water extracts from roots, rhizomes, and aerial parts (stems, leaves and flowers) have antibacterial activity [64,66,[93][94][95], antioxidant effects [44,58,66,[96][97][98][99][100][101][102][103][104][105], anticancer, antiproliferative and apoptotic properties [106][107][108], anti-inflammatory and antiviral activity [11,69,[109][110][111][112] and many other bioactive properties.…”

“…Magacz et al (2021) [95] proved the antibacterial effects of three Reynoutria species against Streptococcus mutans (S. mutans) and the positive impact on the prevention of caries formation. Due to the fact that extracts of the rhizomes of Reynoutria species are a rich source of polyphenols, they can balance the lactoperoxidase cycle, acting as activating/inhibiting agents for the antibacterial activity of the enzyme.…”