The oral cavity is a heterogeneous environment, composed of different habitats with different characteristics, suitable for the establishment of different microbial populations. Microbial communities living in the oral cavity play a key role in oral health because they maintain local homeostasis, resist pathogens, and modulate the immune system. The alteration of this balance allows opportunistic pathogens to predominate and organize themselves in biofilms, determining the onset of oral pathologies often difficult to treat. In this context, the use of natural compounds (propolis, herbs, spices) and probiotics represents an innovative strategy to maintain the health of the oral cavity, reduce the occurrence of pathologies with infectious etiology and limit the inappropriate use of antibiotics that, in recent decades, has led to a dramatic increase in drug-resistance. Recently, a toothpaste (Peribioma) and chewing gum, containing microcrystals of biomimetic hydroxyapatites (microR) and probiotics, useful to limit the tooth sensitivity and keep the oral microbiota in balance, have entered the market. In addition, in vitro studies have provided initial evidence on the effectiveness of pomegranate extract (PomeGr), as a source of bioactive molecules with multiple beneficial effects. Pseudomonas aeruginosa (P. aeruginosa), Staphylococcus aureus (S. aureus) and Candida albicans (C. albicans) are responsible for various clinical manifestations also in the oral cavity. Because of their strong ability to adhere and persist on abiotic and biotic surfaces, they often cause infections associated with biofilms, clinically relevant and difficult to treat. The purpose of this thesis is to evaluate in vitro new tools to counteract the production of bacterial and fungal biofilms in the oral cavity. First, we evaluated in vitro the effects of Peribioma toothpaste and chewable gum on oral microorganisms and their ability to produce biofilm on orthodontic elastic bands. Our study demonstrated the ability of these products to influence the behavior of oral microorganisms, compromising the production of plaque onto orthodontic devices. Secondly, we investigated the effects of microR and PomeGr on biofilm production by P. aeruginosa, S. aureus and C. albicans, showing that PomeGr and microR, alone or in combination, cause a decrease in biofilm production in all cases, though with different effectiveness. Thirdly, we have evaluated in vitro the anti-Candida effects of PomeGr by demonstrating that fungal growth, biofilm formation, and autoinducer release are altered by treatment with PomeGr. In addition, by mass spectrometry, we detected the consumption of various phenolic compounds [pedunclagine, punicalin, punicalagin, grenadine, di-(HHDP-galloil-esoside)-pentoside, ellagic-exoside], suggesting their role as bioactive molecules against Candida. This in vitro data opens the door to clinical studies aimed at defining new protocols to counteract infections associated with oral biofilm.

La cavità orale è un ambiente eterogeneo, composto da diversi habitat con caratteristiche diverse, idonee allo stabilirsi di popolazioni microbiche diverse. Le comunità microbiche residenti nella cavità orale svolgono un ruolo chiave nella salute della bocca perché mantengono l’omeostasi locale, oppongono resistenza agli agenti patogeni e modulano il sistema immunitario. L’alterazione di questo equilibrio consente ai patogeni opportunisti di predominare e organizzarsi in biofilm, determinando l’insorgenza di patologie orali spesso difficili da trattare. In questo contesto, l’impiego di composti naturali (propoli, erbe aromatiche, spezie) e probiotici rappresenta una strategia innovativa per mantenere la salute della cavità orale, ridurre l’insorgenza di patologie ad eziologia infettiva e limitare l’uso inappropriato di antibiotici che, negli ultimi decenni, ha portato ad un drammatico aumento della farmaco-resistenza. Recentemente, sono entrati in commercio un dentifricio (Peribioma) e una gomma da masticare, contenenti microcristalli di idrossiapatite biomimetici (MicroR) e probiotici, utili a limitare la sensibilità dentinale e mantenere il microbiota orale in equilibrio. Inoltre, studi in vitro hanno fornito le prime evidenze sull’efficacia dell’estratto di melograno (PomeGr), come fonte di molecole bioattive con molteplici effetti benefici. Pseudomonas aeruginosa (P. aeruginosa), Staphylococcus aureus (S. aureus) e Candida albicans (C. albicans) sono microrganismi responsabili di diverse manifestazioni cliniche anche nel cavo orale. A causa , infatti, della loro forte capacità di aderire e persistere su superfici abiotiche e biotiche, spesso causano infezioni associate a biofilm, clinicamente rilevanti e difficili da trattare. Lo scopo della presente tesi è quello di valutare in vitro nuovi strumenti per contrastare la produzione di biofilm batterici e fungini nel cavo orale. In primo luogo, abbiamo valutato in vitro gli effetti del dentifricio Peribioma e della gomma masticabile su microrganismi del cavo orale e sulla loro capacità di produrre biofilm su elastici ortodontici. Il nostro studio ha dimostrato la capacità di questi prodotti di influenzare il comportamento dei microrganismi orali, compromettendo la produzione di placca sui dispositivi ortodontici. In secondo luogo, abbiamo studiato gli effetti di MicroR e PomeGr sulla produzione di biofilm da parte di P. aeruginosa, S. aureus e C. albicans, dimostrando che PomeGr e MicroR, da soli o in combinazione, causano un decremento nella produzione di biofilm in tutti i casi, sebbene con efficacia diversa. In terzo luogo, abbiamo valutato in vitro gli effetti anti-candida di PomeGr dimostrando che la crescita fungina, la formazione di biofilm e il rilascio di autoinduttori sono alterati dal trattamento con PomeGr. Inoltre, mediante spettrometria di massa, abbiamo rilevato il consumo di vari composti fenolici [peduncolagina, punicalina, punicalagina, granatina, di-(HHDP-galloil-esoside)-pentoside, ellagico-esoside], suggerendo il loro ruolo come molecole bioattive contro Candida. Questi dati in vitro aprono le porte a studi clinici volti a definire nuovi protocolli per contrastare le infezioni associate al biofilm orale.

Strategie innovative per contrastare la produzione di biofilm batterici e fungini nel cavo orale: studi in vitro / Alessandra Odorici , 2023 May 19. 35. ciclo, Anno Accademico 2021/2022.

Strategie innovative per contrastare la produzione di biofilm batterici e fungini nel cavo orale: studi in vitro

ODORICI, Alessandra
2023

Abstract

The oral cavity is a heterogeneous environment, composed of different habitats with different characteristics, suitable for the establishment of different microbial populations. Microbial communities living in the oral cavity play a key role in oral health because they maintain local homeostasis, resist pathogens, and modulate the immune system. The alteration of this balance allows opportunistic pathogens to predominate and organize themselves in biofilms, determining the onset of oral pathologies often difficult to treat. In this context, the use of natural compounds (propolis, herbs, spices) and probiotics represents an innovative strategy to maintain the health of the oral cavity, reduce the occurrence of pathologies with infectious etiology and limit the inappropriate use of antibiotics that, in recent decades, has led to a dramatic increase in drug-resistance. Recently, a toothpaste (Peribioma) and chewing gum, containing microcrystals of biomimetic hydroxyapatites (microR) and probiotics, useful to limit the tooth sensitivity and keep the oral microbiota in balance, have entered the market. In addition, in vitro studies have provided initial evidence on the effectiveness of pomegranate extract (PomeGr), as a source of bioactive molecules with multiple beneficial effects. Pseudomonas aeruginosa (P. aeruginosa), Staphylococcus aureus (S. aureus) and Candida albicans (C. albicans) are responsible for various clinical manifestations also in the oral cavity. Because of their strong ability to adhere and persist on abiotic and biotic surfaces, they often cause infections associated with biofilms, clinically relevant and difficult to treat. The purpose of this thesis is to evaluate in vitro new tools to counteract the production of bacterial and fungal biofilms in the oral cavity. First, we evaluated in vitro the effects of Peribioma toothpaste and chewable gum on oral microorganisms and their ability to produce biofilm on orthodontic elastic bands. Our study demonstrated the ability of these products to influence the behavior of oral microorganisms, compromising the production of plaque onto orthodontic devices. Secondly, we investigated the effects of microR and PomeGr on biofilm production by P. aeruginosa, S. aureus and C. albicans, showing that PomeGr and microR, alone or in combination, cause a decrease in biofilm production in all cases, though with different effectiveness. Thirdly, we have evaluated in vitro the anti-Candida effects of PomeGr by demonstrating that fungal growth, biofilm formation, and autoinducer release are altered by treatment with PomeGr. In addition, by mass spectrometry, we detected the consumption of various phenolic compounds [pedunclagine, punicalin, punicalagin, grenadine, di-(HHDP-galloil-esoside)-pentoside, ellagic-exoside], suggesting their role as bioactive molecules against Candida. This in vitro data opens the door to clinical studies aimed at defining new protocols to counteract infections associated with oral biofilm.
Novel tools to counteract bacterial and fungal biofilm production: in vitro studies focused on oral cavity
19-mag-2023
BLASI, Elisabetta
BELLINI, Pierantonio
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11380/1305581
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