Bioactivity of flavonoids on lipopolysaccharides-challenged human pulp cells

• Grant number: 22/06603-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2022
• End date: July 31, 2023
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Josimeri Hebling Costa
• Grantee: Rafaella Lara Maia Mota
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Reverting the pro-inflammatory into a pro-regenerative environment remains a challenge in Vital Pulp Therapy. Bioactive molecules have been widely explored for endodontic regeneration in degenerative inflammatory environments, i.e., in adverse pulp conditions. Flavonoids (natural phenolic compounds) have several well-established biological/pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial, and progenitor cell differentiation-inducing properties. All these properties make these molecules ideal candidates for application in regenerative therapies. Considering the lack of scientific evidence regarding the effects of flavonoids on human pulp cells, especially under inflammatory conditions, further investigations are needed to use these compounds for managing pulpopathies. Therefore, this study aims to evaluate the bioactivity of flavonoids on lipopolysaccharide (LPS)-challenged human pulp cells (HDPCs) for modulating regenerative cues in a degenerative inflammatory environment. To accomplish that, the cytocompatibility and bioactivity of different concentrations of the flavonoids quercetin, hesperetin, and taxifolin will be evaluated on HDPCs isolated from third molars (n=4) cultivated in the absence and presence of degenerative inflammatory stimulus with lipopolysaccharide (LPS) from E. coli. As biological analyses, it will be performed cell viability tests (alamarBlue; n=8), modulation of intracellular oxidative stress (Carboxy-H2DCFDA probe; n=8), gene expression of inflammatory mediators and dentinogenic-related genes (RT-qPCR; n=6), and mineralized matrix formation (Alizarin Red; n=8). The number of replicates (n) will vary according to data obtained on each experimental occasion and adjusted for each experimental protocol. Data distribution (Shapiro-Wilk) and homoscedasticity (Levene) will be evaluated to guide the selection of the statistical methods considering 'treatment' and 'presence of LPS' as fixed factors. The statistical inferences will be made considering a level of significance of 5%.(AU)