title: In vitro cytotoxicity evaluation of resveratrol-loaded nanoparticles: Focus on the challenges of in vitro methodologies.
abstract: Assessment of toxic effects is mandatory before market placement of pharmaceutical and cosmetic products. Nanotoxicology is an emerging regulatory concern and still a challenging field. Topical application of resveratrol (RSV) has been extensively studied owing to its multi-mechanistic skin anti-aging effects. Nanoencapsulation has been suggested as a promising solution to overcome RSV stability issues. In this work RSV-loaded solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) were prepared using a homogenization/sonication technique. Cytotoxicity assays were conducted with an immortalized cell line of human keratinocytes (HaCaT). For a comprehensive cytotoxicity characterization MTT and Alamar Blue®reduction assays (assessment of metabolic activity), Neutral red uptake (evaluation of lysosomal integrity), and Trypan blue (assessment of membrane integrity) were used. The results obtained with the different assays were not always concordant, as put in evidence by an adequate statistical analysis. Experimental parameters such as washing steps were found to be critical. The study is of interest because it draws attention to the importance of careful selected experimental conditions of in vitro nanotoxicological tests. Experimental protocols should be adapted taking into account nano-related features such as interference with the dyes and light dispersion/absorption properties.
authors.affiliation: Laboratório de Tecnologia Farmacêutica, Departamento de Ciências do Medicamento, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira nº 228, 4050-313 Porto, Portugal. Electronic address: rocha.veronicapm@gmail.com.
authors.forename: V
authors.initials: V
authors.lastname: Rocha
authors.affiliation: Laboratório de Tecnologia Farmacêutica, Departamento de Ciências do Medicamento, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira nº 228, 4050-313 Porto, Portugal.
authors.forename: C
authors.initials: C
authors.lastname: Marques
authors.affiliation: Laboratório de Tecnologia Farmacêutica, Departamento de Ciências do Medicamento, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira nº 228, 4050-313 Porto, Portugal. Electronic address: jessicalopesfigueiredo@gmail.com.
authors.forename: J L
authors.initials: JL
authors.lastname: Figueiredo
authors.affiliation: Departamento de Matemática, Faculdade de Ciências da Universidade do Porto e Centro de Matemática da Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal. Electronic address: argaio@fc.up.pt.
authors.forename: A R
authors.initials: AR
authors.lastname: Gaio
authors.affiliation: UCIBIO, REQUIMTE, Laboratório de Tecnologia Farmacêutica, Departamento de Ciências do Medicamento, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira nº 228, 4050-313 Porto, Portugal. Electronic address: pccosta@ff.up.pt.
authors.forename: P C
authors.initials: PC
authors.lastname: Costa
authors.affiliation: UCIBIO, REQUIMTE, Laboratório de Tecnologia Farmacêutica, Departamento de Ciências do Medicamento, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira nº 228, 4050-313 Porto, Portugal. Electronic address: slobo@ff.up.pt.
authors.forename: J M
authors.initials: JM
authors.lastname: Sousa Lobo
authors.affiliation: UCIBIO, REQUIMTE, Laboratório de Tecnologia Farmacêutica, Departamento de Ciências do Medicamento, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira nº 228, 4050-313 Porto, Portugal. Electronic address: ifalmeida@ff.up.pt.
authors.forename: I F
authors.initials: IF
authors.lastname: Almeida
mesh_terms: D002460:Cell Line; D004337:Drug Carriers; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects*; D053758:Nanoparticles / Q000009:adverse effects* / Q000737:chemistry; D010316:Particle Size; D000077185:Resveratrol; D013267:Stilbenes / Q000009:adverse effects*; D018675:Toxicity Tests / Q000379:methods*
chemical_list: D004337:Drug Carriers; D013267:Stilbenes; D000077185:Resveratrol
keywords: In vitro cytotoxicity; Keratinocytes; Lipid nanoparticles; Nanotoxicology