title: β-carotene treatment alters the cellular death process in oxidative stress-induced K562 cells.
abstract: Oxidizing agents (e.g., H2O2) cause structural and functional disruptions of molecules by affecting lipids, proteins, and nucleic acids. As a result, cellular mechanisms related to disrupted macro molecules are affected and cell death is induced. Oxidative damage can be prevented at a certain point by antioxidants or the damage can be reversed. In this work, we studied the cellular response against oxidative stress induced by H2O2and antioxidant-oxidant (β-carotene-H2O2) interactions in terms of time, concentration, and treatment method (pre-, co-, and post) in K562 cells. We showed that co- or post-treatment with β-carotene did not protect cells from the damage of oxidative stress furthermore co- and post-β-carotene-treated oxidative stress induced cells showed similar results with only H2O2treated cells. However, β-carotene pre-treatment prevented oxidative damage induced by H2O2at concentrations lower than 1,000 μM compared with only H2O2-treated and co- and post-β-carotene-treated oxidative stress-induced cells in terms of studied cellular parameters (mitochondrial membrane potential [Δψm], cell cycle and apoptosis). Prevention effect of β-carotene pre-treatment was lost at concentrations higher than 1,000 μM H2O2(2-10 mM). These findings suggest that β-carotene pre-treatment alters the effects of oxidative damage induced by H2O2and cell death processes in K562 cells.
authors.affiliation: Department of Biophysics, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey.
authors.forename: Handan
authors.initials: H
authors.lastname: Akçakaya
authors.affiliation: Department of Biophysics, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey.
authors.forename: Sabiha
authors.initials: S
authors.lastname: Tok
authors.affiliation: Department of Biophysics, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey.
authors.forename: Fulya
authors.initials: F
authors.lastname: Dal
authors.affiliation: Department of Immunology, Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Suzan Adin
authors.initials: SA
authors.lastname: Cinar
authors.affiliation: Department of Biophysics, Istanbul Medical Faculty, Istanbul University, Istanbul, Turkey.
authors.forename: Rustem
authors.initials: R
authors.lastname: Nurten
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology*; D016923:Cell Death / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D020014:K562 Cells; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology*; D019207:beta Carotene / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D019207:beta Carotene; D006861:Hydrogen Peroxide
keywords: apoptosis; cancer; cell death; mitochondria; oxidative stress