title: In vitro genotoxicity tests for polyhydroxybutyrate--a synthetic biomaterial.
abstract: The aims of this study are to determine the mutagenicity of a locally produced polyhydroxybutyrate (PHB) using Salmonella mutagenicity test and to find out if PHB altered the expression of p53 and c-myc proto-oncogenes and bcl-xl and bcl-xs anti-apoptotic genes in the human fibroblast cell line, MRC-5. Different concentrations of PHB were incubated with special genotypic variants of Salmonella strains (TA1535, TA1537, TA1538, TA98 and TA100) carrying mutations in several genes both with and without metabolic activation (S9) and the test was assessed based on the number of revertant colonies. The average number of revertant colonies per plate treated with PHB was less than double as compared to that of negative control. For the gene expression analyses, fibroblast cell lines were treated with PHB at different concentrations and incubated for 1, 12, 24 and 48 h separately. The total RNA was isolated and analysed for the expression of p53, c-myc, bcl-xl and bcl-xs genes. The PHB did not show over or under expression of the genes studied. The above tests indicate that the locally produced PHB is non-genotoxic and does not alter the expression of the proto-oncogenes and anti-apoptotic genes considered in this study.
authors: School of Dental Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia.
authors: Abdulaziz Qaid
authors: AQ
authors: Ali
authors: Thirumulu Ponnuraj
authors: TP
authors: Kannan
authors: Azlina
authors: A
authors: Ahmad
authors: Ab Rani
authors: AR
authors: Samsudin
mesh_terms: D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects*; D005838:Genotype; D006801:Humans; D006885:Hydroxybutyrates / Q000008:administration & dosage / Q000633:toxicity*; D066298:In Vitro Techniques; D009152:Mutagenicity Tests; D009153:Mutagens / Q000633:toxicity*; D000091402:Prohibitins; D016271:Proto-Oncogene Proteins c-myc / Q000187:drug effects / Q000235:genetics; D012313:RNA / Q000187:drug effects / Q000378:metabolism; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics; D013997:Time Factors; D016159:Tumor Suppressor Protein p53 / Q000187:drug effects / Q000235:genetics; D051020:bcl-X Protein / Q000187:drug effects / Q000235:genetics
chemical_list: D006885:Hydroxybutyrates; D009153:Mutagens; C000717328:PHB protein, human; D000091402:Prohibitins; D016271:Proto-Oncogene Proteins c-myc; D016159:Tumor Suppressor Protein p53; D051020:bcl-X Protein; D012313:RNA