title: Cytotoxic and genotoxic effects of high concentrations of the immunosuppressive drugs cyclosporine and tacrolimus in MRC-5 cells.
abstract: Immunosuppressive drugs are used to suppress immune system activity in transplant patients and reduce the risk of organ rejection. The present study evaluated the potential cytotoxic, genotoxic and mutagenic of the immunosuppressive drugs cyclosporine (CsA) and tacrolimus (FK-506) on normal human fibroblasts (MRC-5 cells). Based on plasma concentrations of the immunosuppressive drugs, which were obtained from the records of kidney transplant patients at the Kidney Institute of Londrina, Brazil, 11 concentrations of each immunosuppressive were chosen to evaluate cell viability using the MTT assay. From these results, CsA and FK-506 concentrations of 135, 300, 675, and 1520 ng/ml and 8, 16, 24, and 32 ng/ml, respectively, were evaluated using (i) the comet assay, (ii) the nuclear division index (NDI), (iii) the micronucleus test (CBMN) and (iv) cell proliferation curves generated by quantifying cell numbers and protein levels. In this study, 1520 to 3420 ng/ml CsA decreased cell viability after 48 h of exposure. Genotoxic effects were observed only with a concentration of 1520 ng/ml after 3h of exposure and with concentrations of 675 and 1520 ng/ml after 24h of exposure. Mutagenic effects were observed only for the concentration of 1520 ng/ml. FK-506 decreased cell viability after 72 h of exposure for concentrations up to 20 ng/ml; genotoxic effects were observed with concentrations up to 8 ng/ml for both treatment times (3 and 24h) and mutagenic effects were observed with concentrations of 24 and 32 ng/ml after 24h of treatment. The cell proliferation curves demonstrated the absence of cytostatic effects of these drugs, and these data were confirmed by the NDI analysis. Our results suggest that concentrations lower than 300 ng/ml of CsA and 16 ng/ml of FK-506 are safe for use, as they did not induce genotoxic and mutagenic damage or affect MRC-5 cell viability and proliferation.
authors.affiliation: Department of General Biology, Center of Biological Sciences, State University of Londrina, Rodovia Celso Garcia Cid, km 380, 86057-970 Londrina, PR, Brazil. Electronic address: ilcecolus@gmail.com.
authors.forename: H L
authors.initials: HL
authors.lastname: Cilião
authors.affiliation: Department of General Biology, Center of Biological Sciences, State University of Londrina, Rodovia Celso Garcia Cid, km 380, 86057-970 Londrina, PR, Brazil.
authors.forename: D L
authors.initials: DL
authors.lastname: Ribeiro
authors.affiliation: Center of Health Science, State University of Londrina, Londrina, PR, Brazil.
authors.forename: R B O
authors.initials: RB
authors.lastname: Camargo-Godoy
authors.affiliation: Department of General Biology, Center of Biological Sciences, State University of Londrina, Rodovia Celso Garcia Cid, km 380, 86057-970 Londrina, PR, Brazil.
authors.forename: A F L
authors.initials: AF
authors.lastname: Specian
authors.affiliation: Department of Biological Sciences, Faculty of Pharmaceutical Sciences of Araraquara, São Paulo State University "Júlio de Mesquita Filho", Rodovia Araraquara-Jaú, Km 1, 14801-902 Araraquara, SP, Brazil.
authors.forename: J M
authors.initials: JM
authors.lastname: Serpeloni
authors.affiliation: Department of General Biology, Center of Biological Sciences, State University of Londrina, Rodovia Celso Garcia Cid, km 380, 86057-970 Londrina, PR, Brazil.
authors.forename: I M S
authors.initials: IM
authors.lastname: Cólus
mesh_terms: D018929:Cell Culture Techniques; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D020552:Comet Assay; D016572:Cyclosporine / Q000097:blood / Q000633:toxicity*; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000187:drug effects / Q000473:pathology; D006801:Humans; D007166:Immunosuppressive Agents / Q000097:blood / Q000633:toxicity*; D016030:Kidney Transplantation; D048629:Micronuclei, Chromosome-Defective / Q000139:chemically induced*; D015162:Micronucleus Tests; D016559:Tacrolimus / Q000097:blood / Q000633:toxicity*
chemical_list: D007166:Immunosuppressive Agents; D016572:Cyclosporine; D016559:Tacrolimus
keywords: Comet assay; Immunosuppressive drugs; Kidney transplant; MRC-5 cells; MTT assay; Micronucleus test