In vitro toxic evaluation of two gliptins and their main impurities of synthesis

• Published in: BMC pharmacology & toxicology 2019-12, Vol.20 (Suppl 1), p.82-9, Article 82
• Main Authors: Giordani, Camila F A, Campanharo, Sarah, Wingert, Nathalie R, Bueno, Lívia M, Manoel, Joanna W, Costa, Barbara, Cattani, Shanda, Arbo, Marcelo Dutra, Garcia, Solange Cristina, Garcia, Cássia Virginia, Volpato, Nádia Maria, Schapoval, Elfrides Eva Scherman, Steppe, Martin
• Format: Article
• Language: English
• Subjects: 3T3 Cells; Analysis; Animals; Bioassays; Cell culture; Cell Survival - drug effects; Chemicals; Comet assay; Cytotoxicity; Damage detection; Deoxyribonucleic acid; Diabetes; Diabetes mellitus; Diabetics; DNA; DNA Damage; Drug Compounding - standards; Drug Contamination; Drug impurities; Drugs; Evaluation; Experiments; Fibroblasts - drug effects; Fibroblasts - metabolism; Fibroblasts - pathology; Free radicals; Genetic research; Hyperglycemia; Hypoglycemic agents; Hypoglycemic Agents - chemistry; Hypoglycemic Agents - toxicity; Impurities; Membrane potential; Membrane Potential, Mitochondrial - drug effects; Mice; Mitochondria; Nitric oxide; Nitric Oxide - metabolism; Oxidative stress; Pharmaceutical industry; Reactive Oxygen Species - metabolism; Safety; Sitagliptin; Sitagliptin Phosphate - chemistry; Sitagliptin Phosphate - toxicity; Synthesis; Toxicity; Vildagliptin; Vildagliptin - chemistry; Vildagliptin - toxicity
• ISSN: 2050-6511; 2050-6511
• DOI: 10.1186/s40360-019-0354-2

The presence of impurities in some drugs may compromise the safety and efficacy of the patient's treatment. Therefore, establishing of the biological safety of the impurities is essential. Diabetic patients are predisposed to tissue damage due to an increased oxidative stress process; and drug impurities may contribute to these toxic effects. In this context, the aim of this work was to study the toxicity, in 3 T3 cells, of the antidiabetic agents sitagliptin, vildagliptin, and their two main impurities of synthesis (S1 and S2; V1 and V2, respectively). MTT reduction and neutral red uptake assays were performed in cytotoxicity tests. In addition, DNA damage (measured by comet assay), intracellular free radicals (by DCF), NO production, and mitochondrial membrane potential (ΔψM) were evaluated. Cytotoxicity was observed for impurity V2. Free radicals generation was found at 1000 μM of sitagliptin and 10 μM of both vildagliptin impurities (V1 and V2). A decrease in NO production was observed for all vildagliptin concentrations. No alterations were observed in ΔψM or DNA damage at the tested concentrations. This study demonstrated that the presence of impurities might increase the cytotoxicity and oxidative stress of the pharmaceutical formulations at the concentrations studied.