Protective effects of carnosine and homocarnosine on ferritin and hydrogen peroxide-mediated DNA damage

Abstract DNA damage by oxidative stress is one of the causes of mutagenesis. However, whether or not DNA damage induces illegitimate recombination has not been determined. To study the effect of oxidative stress on illegitimate recombination, we examined the frequency of λbio transducing phage in the presence of hydrogen peroxide and found that this reagent enhances illegitimate recombination. To clarify the types of illegitimate recombination, we examined the effect of mutations in mutM and related genes on the process. The frequency of λbio transducing phage was 5- to 12-fold higher in the mutM mutant than in the wild type, while the frequency in the mutY and mutT mutants was comparable to that of the wild type. Because 7,8-dihydro-8-oxoguanine (8-oxoG) and formamido pyrimidine (Fapy) lesions can be removed from DNA by MutM protein, these lesions are thought to induce illegitimate recombination. Analysis of recombination junctions showed that the recombination at Hotspot I accounts for 22 or 4% of total λbio transducing phages in the wild type or in the mutM mutant, respectively. The preferential increase of recombination at nonhotspot sites with hydrogen peroxide in the mutM mutant was discussed on the basis of a new model, in which 8-oxoG and/or Fapy residues may introduce double-strand breaks into DNA.

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Protective effects of cannabidiol on the membrane proteins of skin keratinocytes exposed to hydrogen peroxide via participation in the proteostasis network

Redox Biology ◽

10.1016/j.redox.2021.102074 ◽

2021 ◽

pp. 102074

Author(s):

Sinemyiz Atalay ◽

Agnieszka Gęgotek ◽

Pedro Domingues ◽

Elżbieta Skrzydlewska

Keyword(s):

Hydrogen Peroxide ◽

Membrane Proteins ◽

Protective Effects ◽

Skin Keratinocytes

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Assessment of the protective effects of selected dietary anticarcinogens against DNA damage and cytogenetic effects induced by benzo[a]pyrene in C57BL/6J mice

Food and Chemical Toxicology ◽

10.1016/j.fct.2011.02.021 ◽

2011 ◽

Vol 49 (8) ◽

pp. 1674-1683 ◽

Cited By ~ 13

Author(s):

Dobrosława Gradecka-Meesters ◽

Jadwiga Palus ◽

Gabriela Prochazka ◽

Dan Segerbäck ◽

Elżbieta Dziubałtowska ◽

...

Keyword(s):

Dna Damage ◽

Protective Effects ◽

Cytogenetic Effects

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Protective efficacy of carnosic acid against hydrogen peroxide induced oxidative injury in HepG2 cells through the SIRT1 pathway

Canadian Journal of Physiology and Pharmacology ◽

10.1139/cjpp-2014-0513 ◽

2015 ◽

Vol 93 (8) ◽

pp. 625-631 ◽

Cited By ~ 8

Author(s):

Yan Hu ◽

Ning Zhang ◽

Qing Fan ◽

Musen Lin ◽

Ce Zhang ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Hepg2 Cells ◽

Manganese Superoxide Dismutase ◽

Caspase 3 ◽

Protective Efficacy ◽

B Cell Lymphoma ◽

Sirtuin 1 ◽

Carnosic Acid ◽

Protective Effects ◽

Hepatocyte Damage

Carnosic acid (CA), found in rosemary, has been reported to have antioxidant and antiadipogenic properties. Here, we investigate the molecular mechanism by which CA inhibits hydrogen peroxide (H2O2)-induced injury in HepG2 cells. Cells were pretreated with 2.5–10 μmol/L CA for 2 h and then exposed to 3 mmol/L H2O2 for an additional 4 h. CA dose-dependently increased cell viability and decreased lactate dehydrogenase activities. Pretreatment with CA completely attenuated the inhibited expression of manganese superoxide dismutase (MnSOD) and the B-cell lymphoma-extra large (Bcl-xL), and reduced glutathione activity caused by H2O2, whereas it reversed reactive oxygen species accumulation and the increase in cleaved caspase-3. Importantly, sirtuin 1 (SIRT1), a NAD+-dependent deacetylase, was significantly increased by CA. Considering the above results, we hypothesized that SIRT1 may play important roles in the protective effects of CA in injury induced by H2O2. As expected, SIRT1 suppression by Ex527 (6-chloro-2,3,4,9-tetrahydro-1H-carbazole-1-carboxamide) and siRNA-mediated SIRT1 silencing (si-SIRT1) significantly aggravated the H2O2-induced increased level of cleaved caspase-3 but greatly reduced the decreased expression of MnSOD and Bcl-xL. Furthermore, the positive regulatory effect of CA was inhibited by si-SIRT1. Collectively, the present study indicated that CA can alleviate H2O2-induced hepatocyte damage through the SIRT1 pathway.

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