Cigarette tar causes single-strand breaks in DNA

Borish, Edward T.; Cosgrove, John P.; Church, Daniel F.; Deutsch, Walter; Pryor, William A.

doi:10.1016/0006-291x(85)90972-6

Cited by 91 publications

(42 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The aim of this study was to investigate the effects of curcumin on oxidative stress marker levels and gastritis histopathologic features in patients with chronic gastric associated with H. pylori infection (4,16,24) . Antioxidants can decrease the risk of H. pylori infections and gastric cancer by inhibiting oxidative stress and DNA damage (3) .…”

Section: Discussionmentioning

confidence: 99%

Curcumin in Combination With Triple Therapy Regimes Ameliorates Oxidative Stress and Histopathologic Changes in Chronic Gastritis-Associated Helicobacter Pylori Infection

Judaki

Rahmani

Feizi

et al. 2017

Arq. Gastroenterol.

View full text Add to dashboard Cite

-Background -Helicobacter pylori (H. pylori) gastric infection is a main cause of inflammatory changes and gastric cancers. Objective -The aim of this study was finding the effects of curcumin on oxidative stress and histological changes in chronic gastritis associated with H. pylori. Me thods -In a randomized clinical trial, patients were divided into two groups: a standard triple therapy group and triple therapy with curcumin group. Endoscopic and histological examinations were measured for all patients before and after 8 weeks. Results -Triple therapy with curcumin treatment group significantly decreased malondialdehyde markers, glutathione peroxides and increased total antioxidant capacity of the gastric mucosa at the end of study compared to baseline and triple regimen groups. In addition, the oxidative damage to DNA was significantly decreased in triple therapy with curcumin group at the end of study compared to baseline and compared to triple therapy (P<0.05 for both). Triple therapy group in combination with Curcumin significantly decreased all active, chronic and endoscopic inflammation scores of patients compared to the baseline and triple therapy group (P<0.05 for both). The eradication rate by triple therapy + curcumin was significantly increased compared to triple therapy alone (P<0.05). Conclusion -Curcumin can be a useful supplement to improve chronic inflammation and prevention of carcinogenic changes in patients with chronic gastritis associated by H. pylori. HEADINGS -Gastritis. Helicobacter pylori. Curcumin. Oxidative stress. DNA damage.Declared conflict of interest of all authors: none Disclosure of funding: no funding received

show abstract

Section: Discussionmentioning

confidence: 99%

Curcumin in Combination With Triple Therapy Regimes Ameliorates Oxidative Stress and Histopathologic Changes in Chronic Gastritis-Associated Helicobacter Pylori Infection

Judaki

Rahmani

Feizi

et al. 2017

Arq. Gastroenterol.

View full text Add to dashboard Cite

show abstract

“…The cigarette tar semiquinone radical, as is typical of such radicals, can reduce oxygen to produce superoxide, and hence hydrogen peroxide and the hydroxyl radical. Unlike the tar radical itself, the superoxide and hydroxyl radicals are too reactive and short lived to be observable by direct ESR; but they can be detected by the use of spin trap 5, 5 -dimethyl-1 -pyrroline-N-oxide (DMPO) (78,86,87). Figure 3 Figure 2.…”

Section: Tar Radicalsmentioning

confidence: 99%

“…These ACT solutions can initiate lipid peroxidation, oxidize proteins such as the antiproteinase, a-l-protease inhibitor (88)(89)(90), and nick DNA (82,87). The quinone-hydroquinone-semiquinone system can penetrate viable mammalian cells, bind to, and nick cellular DNA (2,86,87,91,92). The nicks produced by the tar radical require multistep repair, suggesting a process that could be error prone (93).…”

Section: Tar Radicalsmentioning

confidence: 99%

Cigarette Smoke Radicals and the Role of Free Radicals in Chemical Carcinogenicity

Pryor¹

1997

Environmental Health Perspectives

Self Cite

View full text Add to dashboard Cite

This article consists of two parts: a brief overview of the ways in which free radicals can be involved in chemical carcinogenesis, and a review of cigarette smoke chemistry. Carcinogenesis is generally agreed to involve at least three stages: initiation, promotion, and progression. It is suggested that radicals sometimes are involved in the initiation step, either in the oxidative activation of a procarcinogen (such as benzo[alpyrene) to its carcinogenic form or in the binding of the carcinogenic species to DNA, or both. The fraction of initiation events that involve radicals, as opposed to two-electron steps, is not known, but radicals probably are involved in a substantial number, although probably not a majority, of cancer initation reactions. Promotion always involves radicals, at least to some extent. Progression probably does not normally involve radicals. The second part of this article reviews the molecular mechanisms involved in cigarette-induced tumors, particularly by aqueous cigarette tar (ACT) extracts and by a model of these solutions, aged solutions of catechol. ACT solutions as well as aged solutions of catechol contain a quinone-hydroquinone-semiquinone system that can reduce oxygen to produce superoxide and hence hydrogen peroxide and the hydroxyl radical. Both the cigarette tar radical and the catecholderived radical can penetrate viable cells, bind to DNA, and cause nicks.Environ Health Perspect 1 05(Suppl 4): 875-882 (1997)

show abstract

“…When calf thymus DNA is incubated This paper was presented at the Conference on with buffer solutions containing the tar radical, the DNA recovered by precipitation contains the tar radical ESR signal, and this signal is not removed by washing the DNA (7). Aqueous cigarette tar extracts nick plasmid DNA (8), producing nicks that are not easily repairable (9); thus, error-prone mechanisms may be involved in the repair of the tar radicalinduced nicks and these erroneous repairs could lead to mutations. When plasmid DNA is incubated with ACT, the resultant DNA nicking appears to follow saturation kinetics (10).…”

Section: Introductionmentioning

confidence: 99%

Aqueous extracts of cigarette tar containing the tar free radical cause DNA nicks in mammalian cells.

Stone

Bermúdez

Pryor

1994

Environ Health Perspect

View full text Add to dashboard Cite

The ability of aqueous extracts of cigarette tar to nick DNA was investigated using viable mammalian cells. Tar extracts contain a radical with a stable electron spin resonance (ESR) signal at g = 2.0036 characteristic of a semiquinone. The association of the tar component that carries the ESR signal with DNA was demonstrated using viable rat alveolar macrophages. The formation of single-strand DNA breaks caused by cigarette tar extracts in viable rat thymocytes follows saturation kinetics, indicating a tar component associates with DNA and then nicks it. These studies support our hypothesis that tar components that contain the cigarette tar radical can enter cells, associate with, and then nick DNA. -Environ Health Perspect 102(Suppl 10): 173-178 (1994)

show abstract

Cigarette tar causes single-strand breaks in DNA

Cited by 91 publications

References 15 publications

Curcumin in Combination With Triple Therapy Regimes Ameliorates Oxidative Stress and Histopathologic Changes in Chronic Gastritis-Associated Helicobacter Pylori Infection

Curcumin in Combination With Triple Therapy Regimes Ameliorates Oxidative Stress and Histopathologic Changes in Chronic Gastritis-Associated Helicobacter Pylori Infection

Cigarette Smoke Radicals and the Role of Free Radicals in Chemical Carcinogenicity

Aqueous extracts of cigarette tar containing the tar free radical cause DNA nicks in mammalian cells.

Contact Info

Product

Resources

About