title: Effect of 5-ALA-mediated photodynamic therapy on mast cell and microvessels densities present in oral premalignant lesions induced in rats.
abstract: Acute inflammatory response after photodynamic therapy is frequently described, and increase on mast cell degranulation is also present during this process. The mast cell activation may improve angiogenesis, and this fact has been associated with progression of oral premalignant lesions (OPL). The aim of this study was to evaluate whether photodynamic therapy (PDT) increases mast cell density (MCD) and microvessels density (MVD) in 4-nitroquinoline-1-oxide(4NQO)-induced OPL in rats. 4NQO-induced OPL were treated or not with 5-ALA followed by laser irradiation (PDT group and 4NQO groups, respectively). Mast cells and CD34+ microvessels were counted. Both PDT and 4NQO groups had MCD and MVD that were higher than normal mucosa (p b 0.05). The 4NQO group had the lowest number of non-degranulated MCD in comparison to experimental periods of PDT (PDT 6 h – p=0.020; 24 h – p=0.016; 48 h – p=0.003; 72 h – p=0.033). Only in the PDT group did MCD and MVD have a significant correlation (r= 0.6219, p = 0.010). 5-ALA-mediated PDT modified the MCD and MVD in the induced OPL, leading to degranulation of mast cells and angiogenesis. A PDT protocol with an efficient eradication of the OPL must be adopted considering the angiogenesis potential associated with the mast cell activation after the therapy.
authors.affiliation: General Pathology Department, School of Dentistry, University of São Paulo, São Paulo, Brazil.
authors.forename: Flavia Cristina Perillo
authors.initials: FC
authors.lastname: Rosin
authors.affiliation: Health Department, School of Nursing, Federal University of Amapá, Macapá, Brazil.
authors.forename: Ana Rita Pinheiro
authors.initials: AR
authors.lastname: Barcessat
authors.affiliation: General Pathology Department, School of Dentistry, University of São Paulo, São Paulo, Brazil.
authors.forename: Giuliana Gadoni
authors.initials: GG
authors.lastname: Borges
authors.affiliation: General Pathology Department, School of Dentistry, University of São Paulo, São Paulo, Brazil. Electronic address: lcorrea@usp.br.
authors.forename: Luciana
authors.initials: L
authors.lastname: Corrêa
mesh_terms: D015112:4-Nitroquinoline-1-oxide / Q000633:toxicity; D000622:Aminolevulinic Acid / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D018952:Antigens, CD34 / Q000378:metabolism; D015550:Cell Degranulation / Q000187:drug effects / Q000528:radiation effects; D005260:Female; D006965:Hyperplasia / Q000139:chemically induced / Q000473:pathology; D007834:Lasers; D008407:Mast Cells / Q000166:cytology / Q000502:physiology*; D055806:Microvessels / Q000473:pathology*; D009061:Mouth Mucosa / Q000187:drug effects / Q000473:pathology; D018919:Neovascularization, Physiologic / Q000187:drug effects / Q000528:radiation effects; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000494:pharmacology / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D014059:Tongue / Q000473:pathology; D014062:Tongue Neoplasms / Q000139:chemically induced / Q000188:drug therapy* / Q000662:veterinary
chemical_list: D018952:Antigens, CD34; D017319:Photosensitizing Agents; D015112:4-Nitroquinoline-1-oxide; D000622:Aminolevulinic Acid
keywords: 4-nitroquinoline-1-oxide; Angiogenesis; Mast cells; Oral premalignant lesions; Photodynamic therapy