Antioxidant and DNA Repair Stimulating Effect of Extracts from Transformed and Normal Roots ofRhaponticum carthamoidesagainst Induced Oxidative Stress and DNA Damage in CHO Cells

Rhaponticum carthamoideshas a long tradition of use in Siberian folk medicine. The roots and rhizomes of this species are used in various dietary supplements or nutraceutical preparations to increase energy level or eliminate physical weakness. This is the first report to reveal the protective and DNA repair stimulating abilities ofR. carthamoidesroot extracts in Chinese hamster ovary (CHO) cells exposed to an oxidative agent. Both transformed root extract (TR extract) and extract of soil-grown plant roots (NR extract) may be responsible for stimulating CHO cells to repair oxidatively induced DNA damage, but CHO cells stimulated with extract from the transformed roots demonstrated significantly stronger properties than cells treated with the soil-grown plant root extract. These differences in biological activity may be attributed to the differences in the content of phenolic compounds in these root extracts. Preincubation of the CHO cells with TR and NR extracts showed an increase in gene expression and protein levels of catalase (CAT) and superoxide dismutase (SOD2).R. carthamoidesmay possess antioxidant properties that protect CHO cells against oxidative stress.

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The Effect ofLeonurus sibiricusPlant Extracts on Stimulating Repair and Protective Activity against Oxidative DNA Damage in CHO Cells and Content of Phenolic Compounds

Oxidative Medicine and Cellular Longevity ◽

10.1155/2016/5738193 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 16

Author(s):

Przemysław Sitarek ◽

Ewa Skała ◽

Halina Wysokińska ◽

Marzena Wielanek ◽

Janusz Szemraj ◽

...

Keyword(s):

Dna Damage ◽

Phenolic Compounds ◽

Plant Extracts ◽

Cho Cells ◽

Oxidative Dna Damage ◽

Antioxidant Properties ◽

Chinese Hamster ◽

Antioxidant Genes ◽

Aerial Parts

Leonurus sibiricusL. has been used as a traditional and medicinal herb for many years in Asia and Europe. This species is known to have antibacterial, anti-inflammatory, and antioxidant activity and has demonstrated a reduction of intracellular reactive oxygen species. All tested extracts ofL. sibiricusshowed protective and DNA repair stimulating effects in Chinese hamster ovary (CHO) cells exposed to H2O2. Preincubation of the CHO cells with 0.5 mg/mL of plant extracts showed increased expression level of antioxidant genes (SOD2, CAT,andGPx). LC-MS/MS and HPLC analyses revealed the presence of nine phenolic compounds inL. sibiricusplant extracts: catechin, verbascoside, two flavonoids (quercetin and rutin), and five phenolic acids (4-hydroxybenzoic acid, chlorogenic acid, caffeic acid,p-coumaric acid, and ferulic acid). The roots and aerial parts ofin vitro L. sibiricusplant extracts, which had the strongest antioxidant properties, may be responsible for stimulating CHO cells to repair oxidatively induced DNA damage, as well as protecting DNA via enhanced activation of the antioxidant genes (SOD2, CAT,andGPx) regulating intracellular antioxidant capacity. The content of phenolic compounds inin vitroraised plants was greater than the levels found in plants propagated from seeds.

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8. Evaluation of Snow Fungus Polysaccharides on benzo[a]pyrene-induced DNA Damage

Inquiry@Queen's Undergraduate Research Conference Proceedings ◽

10.24908/iqurcp.10074 ◽

2018 ◽

Author(s):

Daisy Liu

Keyword(s):

Oxidative Stress ◽

Dna Damage ◽

Free Radical ◽

Radical Scavenging ◽

Chinese Hamster ◽

Negative Control ◽

Lung Fibroblasts ◽

Protective Effects ◽

Tremella Fuciformis

Snow fungus, Tremella fuciformis, has been demonstrated to have numerous health benefits including purported chemopreventive properties due to free radical-scavenging ability. Protective effects derived from snow fungus polysaccharides are evaluated on Chinese hamster lung fibroblasts (CCL-39) exposed to carcinogen benzo[a]pyrene known to cause free radical formation and oxidative stress to cells. In this experiment, it was hypothesized that the naturally occurring polysaccharides in snow fungus are able to protect against or reduce oxidative stress-induced DNA damage. Polysaccharides were isolated through an alkaline extraction and in-vitro digestion. DNA damage was measured using the single-cell gel electrophoresis comet assay after exposure to benzo[a]pyrene and polysaccharide extract to lung fibroblasts. Results were calculated using the mean and standard deviation data of tail length and area, respectively. Each damaged cell was measured and analyzed through ImageJ Editing Software. The results indicate a promising trend which depict snow fungus polysaccharides yielding lower levels of DNA damage compared to cells exposed to benzo[a]pyrene and compared to the negative control (phosphate buffered saline and Dulbecco’s cell medium). This study suggests polysaccharides from Tremella fuciformis could truly prevent cellular DNA damage by protecting against oxidative stress.

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Aging and oxidative stress alter DNA repair mechanisms in male germ cells of superoxide dismutase-1 null mice

Biology of Reproduction ◽

10.1093/biolre/ioab114 ◽

2021 ◽

Author(s):

Paulina Nguyen-Powanda ◽

Bernard Robaire

Keyword(s):

Oxidative Stress ◽

Dna Damage ◽

Dna Repair ◽

Superoxide Dismutase ◽

Germ Cells ◽

Superoxide Dismutase 1 ◽

Male Germ Cells ◽

Dna Repair Mechanisms ◽

Repair Mechanisms ◽

And Oxidative Stress

Abstract The efficiency of antioxidant defense system decreases with aging, thus resulting in high levels of reactive oxygen species (ROS) and DNA damage in spermatozoa. This damage can lead to genetic disorders in the offspring. There are limited studies investigating the effects of the total loss of antioxidants, such as superoxide dismutase-1 (SOD1), in male germ cells as they progress through spermatogenesis. In this study, we evaluated the effects of aging and removing SOD1 (in male germ cells of SOD1-null (Sod1−/−) mice) in order to determine the potential mechanism(s) of DNA damage in these cells. Immunohistochemical analysis showed an increase in lipid peroxidation and DNA damage in the germ cells of aged wild-type (WT) and Sod1−/− mice of all age. Immunostaining of OGG1, a marker of base excision repair (BER), increased in aged WT and young Sod1−/− mice. In contrast, immunostaining intensity of LIGIV and RAD51, markers of non-homologous end-joining (NHEJ) and homologous recombination (HR), respectively, decreased in aged and Sod1−/− mice. Gene expression analysis showed similar results with altered mRNA expression of these key DNA repair transcripts in pachytene spermatocytes and round spermatids of aged and Sod1−/− mice. Our study indicates that DNA repair pathway markers of BER, NHEJ, and HR are differentially regulated as a function of aging and oxidative stress in spermatocytes and spermatids, and aging enhances the repair response to increased oxidative DNA damage, whereas impairments in other DNA repair mechanisms may contribute to the increase in DNA damage caused by aging and the loss of SOD1.

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Evaluation of DNA Damage, DNA Repair, Oxidative Stress, and Cell Death Caused by Helicobacter pylori in Human Adenocarcinoma Cells

SSRN Electronic Journal ◽

10.2139/ssrn.3972034 ◽

2021 ◽

Author(s):

DİDEM ORAL ◽

ÜNZİLE SUR ◽

gizem özkemahlı ◽

Anıl Yirüna ◽

N. DİLARA ZEYBEK ◽

...

Keyword(s):

Oxidative Stress ◽

Dna Damage ◽

Cell Death ◽

Dna Repair ◽

Helicobacter Pylori ◽

Adenocarcinoma Cells

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Dynamic Compartmentalization of Base Excision Repair Proteins in Response to Nuclear and Mitochondrial Oxidative Stress

Molecular and Cellular Biology ◽

10.1128/mcb.01357-08 ◽

2008 ◽

Vol 29 (3) ◽

pp. 794-807 ◽

Cited By ~ 31

Author(s):

Lyra M. Griffiths ◽

Dan Swartzlander ◽

Kellen L. Meadows ◽

Keith D. Wilkinson ◽

Anita H. Corbett ◽

...

Keyword(s):

Oxidative Stress ◽

Dna Damage ◽

Dna Repair ◽

Base Excision Repair ◽

Oxidative Dna Damage ◽

Excision Repair ◽

Intracellular Localization ◽

Genotoxic Stress ◽

Mitochondrial Oxidative Stress ◽

Base Excision

ABSTRACT DNAs harbored in both nuclei and mitochondria of eukaryotic cells are subject to continuous oxidative damage resulting from normal metabolic activities or environmental insults. Oxidative DNA damage is primarily reversed by the base excision repair (BER) pathway, initiated by N-glycosylase apurinic/apyrimidinic (AP) lyase proteins. To execute an appropriate repair response, BER components must be distributed to accommodate levels of genotoxic stress that may vary considerably between nuclei and mitochondria, depending on the growth state and stress environment of the cell. Numerous examples exist where cells respond to signals, resulting in relocalization of proteins involved in key biological transactions. To address whether such dynamic localization contributes to efficient organelle-specific DNA repair, we determined the intracellular localization of the Saccharomyces cerevisiae N-glycosylase/AP lyases, Ntg1 and Ntg2, in response to nuclear and mitochondrial oxidative stress. Fluorescence microscopy revealed that Ntg1 is differentially localized to nuclei and mitochondria, likely in response to the oxidative DNA damage status of the organelle. Sumoylation is associated with targeting of Ntg1 to nuclei containing oxidative DNA damage. These studies demonstrate that trafficking of DNA repair proteins to organelles containing high levels of oxidative DNA damage may be a central point for regulating BER in response to oxidative stress.

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