title: Malva sylvestris Inhibits Inflammatory Response in Oral Human Cells. An In Vitro Infection Model.
abstract: The aim of this study was to investigate the in vitro anti-inflammatory activity of Malva sylvestris extract (MSE) and fractions in a co-culture model of cells infected by Aggregatibacter actinomycetemcomitans. In addition, we evaluated the phytochemical content in the extract and fractions of M. sylvestris and demonstrated that polyphenols were the most frequent group in all samples studied. An in vitro dual-chamber model to mimic the periodontal structure was developed using a monolayer of epithelial keratinocytes (OBA-9) and a subepithelial layer of fibroblasts (HGF-1). The invasive periodontopathogen A. actinomycetemcomitans (D7S-1) was applied to migrate through the cell layers and induce the synthesis of immune factors and cytokines in the host cells. In an attempt to analyze the antimicrobial properties of MSE and fractions, a susceptibility test was carried out. The extract (MIC 175 μg/mL, MBC 500μg/mL) and chloroform fraction (MIC 150 μg/mL, MBC 250 μg/mL) were found to have inhibitory activity. The extract and all fractions were assessed using a cytotoxicity test and results showed that concentrations under 100 μg/mL did not significantly reduce cell viability compared to the control group (p > 0.05, viability > 90%). In order to analyze the inflammatory response, transcriptional factors and cytokines were quantified in the supernatant released from the cells. The chloroform fraction was the most effective in reducing the bacterial colonization (p< 0.05) and controlling inflammatory mediators, and promoted the down-regulation of genes including IL-1beta, IL-6, IL-10, CD14, PTGS, MMP-1 and FOS as well as the reduction of the IL-1beta, IL-6, IL-8 and GM-CSF protein levels (p< 0.05). Malva sylvestris and its chloroform fraction minimized the A. actinomycetemcomitans infection and inflammation processes in oral human cells by a putative pathway that involves important cytokines and receptors. Therefore, this natural product may be considered as a successful dual anti-inflammatory-antimicrobial candidate.
authors.affiliation: Department of Physiological Sciences, Piracicaba Dental School, University of Campinas, Piracicaba, Sao Paulo, Brazil.
authors.forename: Bruna
authors.initials: B
authors.lastname: Benso
authors.affiliation: Department of Physiological Sciences, Piracicaba Dental School, University of Campinas, Piracicaba, Sao Paulo, Brazil.
authors.forename: Pedro Luiz
authors.initials: PL
authors.lastname: Rosalen
authors.affiliation: Department of Agri-food Industry, Food and Nutrition, "Luiz de Queiroz" College of Agriculture, University of Sao Paulo, Piracicaba, Sao Paulo, Brazil.
authors.forename: Severino Matias
authors.initials: SM
authors.lastname: Alencar
authors.affiliation: Division of Periodontology, Diagnostic Sciences & Dental Hygiene and Division of Biomedical Sciences Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, United States of America.
authors.forename: Ramiro Mendonça
authors.initials: RM
authors.lastname: Murata
mesh_terms: D016976:Aggregatibacter actinomycetemcomitans / Q000472:pathogenicity; D000890:Anti-Infective Agents / Q000494:pharmacology; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D017209:Apoptosis; D002465:Cell Movement; D049109:Cell Proliferation; D002478:Cells, Cultured; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007249:Inflammation / Q000276:immunology / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D015603:Keratinocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D028501:Malva / Q000737:chemistry*; D009055:Mouth / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D010936:Plant Extracts / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D000890:Anti-Infective Agents; D000893:Anti-Inflammatory Agents; D016207:Cytokines; D010936:Plant Extracts; D012333:RNA, Messenger