Evaluation of curcumin and cisplatin-induced DNA damage in PC12 cells by the alkaline comet assay.
A very appropriate method for antigenotoxicity evaluation of antioxidants is the comet assay, since this analytical method detects initial DNA lesions that are still subject to repair; in other words, lesions that are very associated to damages resulting from the generation and subsequent action of reactive species. However, a solid evaluation should be developed in order to avoid inexact interpretations. In our study, besides the association of curcumin with cisplatin, curcumin and cisplatin agents were also tested separately. Classical genotoxic compounds, when tested by the comet assay, present an increase in the nucleoid tail; however, the cisplatin treatment has resulted in a decrease of DNA migration. This was an expected effect, as the cross-links between cisplatin and DNA decrease the DNA electrophoretic mobility. A similar effect was observed with the curcumin treatment, which decreased the nucleoid tail. Such effect was not expected and reinforced the necessity of including in the study, separate treatment groups with potentially antigenotoxic substances. The comet assay results have been analyzed using specific software for image analysis, as well as the classical visual analysis, and we have observed that the effect of decrease in DNA electrophoretic mobility was more easily observed when the data were analyzed by the software.
Mendonça
Leonardo Meneghin
LM
Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
dos Santos
Graciela Cristina
GC
dos Santos
Raquel Alves
RA
Takahashi
Catarina Satie
CS
Bianchi
Maria de Lourdes Pires
Mde L
Antunes
Lusânia Maria Greggi
LM
D000818:Animals; D000970:Antineoplastic Agents / Q000633:toxicity*; D002945:Cisplatin / Q000633:toxicity*; D020552:Comet Assay; D003474:Curcumin / Q000633:toxicity*; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D007091:Image Processing, Computer-Assisted; D009153:Mutagens / Q000633:toxicity; D016716:PC12 Cells; D051381:Rats
D000970:Antineoplastic Agents; D009153:Mutagens; D003474:Curcumin; D002945:Cisplatin