title: Violacein induces cell death by triggering mitochondrial membrane hyperpolarization in vitro.
abstract: BACKGROUND
  Violacein is a purple pigment from Chromobacterium violaceum that possesses diverse biological and pharmacological properties. Among these, pro-oxidant and antioxidant activities have been suggested. However, the cytotoxic mechanisms induced by violacein are poorly understood and the improvement in knowledge regarding these cell death mechanisms will be useful to develop new therapeutic approaches. Considering this, in our work, we investigated the pro-oxidant effects of violacein in non-tumor (CHO-K1 and MRC-5) and tumor (HeLa) cell lines, searching for a better understanding of reactive oxygen species (ROS) production and cell death induction.
  
  
  RESULTS
  Cytotoxicity induced by violacein was observed in the three cell lines; however, MRC-5 and HeLa cells were shown to be more sensitive to violacein treatment. Although punctual alterations in the antioxidant apparatus and increase in oxidative stress biomarkers was observed in some violacein concentrations, no association was found between increased oxidative stress and induction of cell death. However, the increase of mitochondrial membrane potential was observed.
  
  
  CONCLUSIONS
  In fact, the increase of mitochondrial membrane potential in MRC-5 and HeLa cells suggests that mitochondrial membrane hyperpolarization might be the main cause of cell death triggered by violacein.
authors.affiliation: Departamento de Biologia Celular e Genética, Universidade Federal do Rio Grande do Norte, CEP 59072-970, Natal, RN, Brazil. Angelicaleal@outlook.com.
authors.forename: Angélica Maria de Sousa
authors.initials: AM
authors.lastname: Leal
authors.affiliation: Departamento de Biologia Celular e Genética, Universidade Federal do Rio Grande do Norte, CEP 59072-970, Natal, RN, Brazil. Jana_dara@hotmail.com.
authors.forename: Jana Dara Freires
authors.initials: JD
authors.lastname: de Queiroz
authors.affiliation: Departamento de Biologia Celular e Genética, Universidade Federal do Rio Grande do Norte, CEP 59072-970, Natal, RN, Brazil. Sbatistu@gmail.com.
authors.forename: Silvia Regina Batistuzzo
authors.initials: SR
authors.lastname: de Medeiros
authors.affiliation: Departamento de Biologia Celular e Molecular, Centro de Biotecnologia, Universidade Federal da Paraíba, CEP 58051-900, João Pessoa, PB, Brazil. Tat.keesen@gmail.com.
authors.forename: Tatjana Keesen de Souza
authors.initials: TK
authors.lastname: Lima
authors.affiliation: Departamento de Biologia Celular e Genética, Universidade Federal do Rio Grande do Norte, CEP 59072-970, Natal, RN, Brazil. lfagnez@ufrnet.br.
authors.forename: Lucymara Fassarella
authors.initials: LF
authors.lastname: Agnez-Lima
mesh_terms: D000818:Animals; D016466:CHO Cells; D016923:Cell Death; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003412:Cricetulus; D006367:HeLa Cells; D006801:Humans; D007211:Indoles / Q000494:pharmacology / Q000633:toxicity*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects*; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D007211:Indoles; D017382:Reactive Oxygen Species; C063155:violacein