title: Interaction between 2-ethoxybenzoic acid (EBA) and eugenol, and related changes in cytotoxicity.
abstract: The liquid of 2-ethoxybenzoic acid cements is composed of 2-ethoxybenzoic acid and eugenol (4-allyl-2-methoxyphenol). Recently, eugenol was reported to produce radicals at a higher pH, which consequently directly damages cells. We examined here whether eugenol radicals are generated from the mixture of eugenol/calcium hydroxide, and also whether 2-ethoxybenzoic acid or acetylsalicylic acid scavenges radicals, using electron spin resonance spectroscopy. Radicals were generated from the mixture of eugenol/calcium hydroxide in 50% dimethylsulfoxide solution. The radical intensity of eugenol in 50% dimethylsulfoxide with 0.1 M sodium bicarbonate buffer (pH 9.5) was dose-dependently reduced by 2-ethoxybenzoic acid, whereas it was enhanced by acetylsalicylic acid. Next, we investigated the cytotoxic effect of eugenol on 2-ethoxybenzoic acid, acetylsalicylic acid, or calcium hydroxide on human pulp fibroblasts or a human submandibular gland cancer cell line. The cytotoxicity of EBA was decreased, whereas that of acetylsalicylic acid was increased by eugenol. In contrast, that of calcium hydroxide was not affected by eugenol. Human pulp fibroblast but not human submandibular gland cells showed a high resistance against calcium hydroxide. The generation of eugenol radicals in the liquid of 2-ethoxybenzoic acid cements caused by oxidation may be suppressed by 2-ethoxybenzoic acid.
authors.affiliation: Department of Oral Diagnosis, Meikai University, School of Dentistry, Sakado, Saitama, Japan. fujisawa@dent.meikai.ac.jp
authors.forename: S
authors.initials: S
authors.lastname: Fujisawa
authors.forename: T
authors.initials: T
authors.lastname: Atsumi
authors.forename: K
authors.initials: K
authors.lastname: Satoh
authors.forename: H
authors.initials: H
authors.lastname: Sakagami
mesh_terms: D001241:Aspirin / Q000737:chemistry; D001672:Biocompatible Materials / Q000633:toxicity; D002126:Calcium Hydroxide / Q000737:chemistry; D018929:Cell Culture Techniques; D003738:Dental Cements / Q000737:chemistry* / Q000633:toxicity; D003782:Dental Pulp / Q000166:cytology / Q000187:drug effects; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D004578:Electron Spin Resonance Spectroscopy; D005054:Eugenol / Q000737:chemistry* / Q000633:toxicity; D005347:Fibroblasts / Q000187:drug effects; D016166:Free Radical Scavengers / Q000737:chemistry; D005609:Free Radicals / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D062425:Hydroxybenzoate Ethers; D062385:Hydroxybenzoates / Q000737:chemistry* / Q000633:toxicity; D010084:Oxidation-Reduction; D017693:Sodium Bicarbonate / Q000737:chemistry; D013365:Submandibular Gland Neoplasms / Q000473:pathology / Q000503:physiopathology; D014407:Tumor Cells, Cultured
chemical_list: D001672:Biocompatible Materials; D003738:Dental Cements; D016166:Free Radical Scavengers; D005609:Free Radicals; D062425:Hydroxybenzoate Ethers; D062385:Hydroxybenzoates; C029266:2-ethoxybenzoic acid; D005054:Eugenol; D017693:Sodium Bicarbonate; D002126:Calcium Hydroxide; D001241:Aspirin; D004121:Dimethyl Sulfoxide