Protective effects of Hibiscus tiliaceus L. methanolic extract to V79 cells against cytotoxicity and genotoxicity induced by hydrogen peroxide and tert-butyl-hydroperoxide.
Plants of the genus Hibiscus thrives produce a diversity of molecules with bioactive properties. In a previous study of Hibiscus tiliaceus L. methanolic extract (HME) using bacteria and yeast, as test media, it has been shown that HME strongly inhibited the mutagenic action of H(2)O(2) or tert-butyl-hydroperoxide (t-BHP). Here, our interest is to evaluate the genotoxicity and the antigenotoxic/antimutagenic properties of HME using oxidative challenge with H(2)O(2) and t-BHP in V79 cells. We determined cytotoxicity using clonal survival assay; evaluated DNA damage using the comet assay and the micronucleus test in binucleated cells besides of the lipid peroxidation degree and the reduced glutathione content. We examined the ability of HME in quenching hydroxyl radical by means of a HPLC-based method utilizing the hypoxanthine/xanthine oxidase assay. At concentrations ranging from 0.001 to 0.1mg/mL, HME was not cytotoxic, genotoxic or mutagenic. Treatment with non-cytotoxic concentrations of HME increased cell survival after H(2)O(2) and t-BHP exposure and prevented DNA damage. The pre-treatment with HME also was able to decrease the mutagenic effect of these genotoxins, evaluated using the micronucleus test. HME prevented the increase in lipid peroxidation and decrease in GSH content in response to the oxidative challenge. Therefore, the ability in preventing against H(2)O(2)- and t-BHP-induced GSH depletion and lipid peroxidation was probably a major contribution to the cytoprotective effects. Moreover, HME acts as a hydroxyl radical scavenger. In summary, HME did not have a harmful or inhibitory effect on the growth of V79 cells and presented antioxidant activity, consequently, both antigenotoxic and antimutagenic effects against oxidative DNA damage.
Departamento de Biofísica, Instituto de Biociências, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Renato Moreira
RM
Rosa
Dinara Jaqueline
DJ
Moura
Maria Inês S
MI
Melecchi
Rafael Santos
RS
dos Santos
Marc François
MF
Richter
Elina Bastos
EB
Camarão
João Antonio Pêgas
JA
Henriques
Ana Lígia Lia
AL
de Paula Ramos
Jenifer
J
Saffi
D000818:Animals; D002460:Cell Line; D002875:Chromosomes / Q000187:drug effects; D006224:Cricetinae; D003603:Cytotoxins / Q000633:toxicity; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D016166:Free Radical Scavengers; D005978:Glutathione; D031584:Hibiscus / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000633:toxicity*; D017665:Hydroxyl Radical; D015227:Lipid Peroxidation; D009153:Mutagens / Q000633:toxicity*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D020122:tert-Butylhydroperoxide / Q000633:toxicity*
D003603:Cytotoxins; D016166:Free Radical Scavengers; D009153:Mutagens; D010936:Plant Extracts; D017665:Hydroxyl Radical; D020122:tert-Butylhydroperoxide; D006861:Hydrogen Peroxide; D005978:Glutathione