DNA Damage In Buccal Cells Research Articles

DNA damage level in lymphocytes and buccal epithelial cells in Narghile smokers and non-smokers in Duhok city-KRG-Iraq

IntroductionThere are different ways for Tobacco consumption among smokers. The main three ways for smoking are Cigarettes, Cigar and Narghile (the waterpipie). Narghile smoking has become a very popular habit among youth in different countries around the world. ResultsThere is higher frequency of micronuclei formation in cigarettes and Narghile smokers compared to control group (7.1 ​± ​0.9, 11.2 ​± ​0.4, and 2.2 ​± ​0.7 respectively). The mean frequency of the DNA fading (Karyolysis) in Narghile smokers was 29-fold higher than non-smokers. The mean frequencies of Karyorhexis buccal cells in Narghile smokers were 1.9-fold higher than non-smokers. The mean of Pyknosis formation was 19-fold greater than non-smokers. More migrated DNA tails were found Narghile smokers compared to controls. The mean of DNA damage measured by ACA was significantly greater (p ​< ​0.0001) than in non-smokers (53.32 ​± ​3.435 ​N ​= ​26 vs. 22.61 ​± ​1.909 ​N ​= ​21, respectively). Narghile smoking increased frequencies of micronucleus formation in buccal cells of Narghile smokers (p ​< ​0.005) compared to cigarettes smokers and non-smokers. The mean of DNA damage measured in peripheral blood cells of Narghile smokers was significantly greater (p ​< ​0.0001) than in non-smokers. ConclusionIn our study we have found direct and accumulative genomic damage effect of smoking in cigarette and Narghile smokers. Narghile smoking causes more DNA damage in buccal cells and in peripheral blood cells. This could be an evidence indicating that there is accumulative effect of Narghile smoking on genomic stability in peripheral blood cells and as well as in buccal epithelial cells.

Exposure to Particulate PAHs on Potential Genotoxicity and Cancer Risk among School Children Living Near the Petrochemical Industry.

This study aimed to assess the association of exposure to particle-bound (PM2.5) polycyclic aromatic hydrocarbons (PAHs) with potential genotoxicity and cancer risk among children living near the petrochemical industry and comparative populations in Malaysia. PM2.5 samples were collected using a low-volume sampler for 24 h at three primary schools located within 5 km of the industrial area and three comparative schools more than 20 km away from any industrial activity. A gas chromatography–mass spectrometer was used to determine the analysis of 16 United States Environmental Protection Agency (USEPA) priority PAHs. A total of 205 children were randomly selected to assess the DNA damage in buccal cells, employing the comet assay. Total PAHs measured in exposed and comparative schools varied, respectively, from 61.60 to 64.64 ng m−3 and from 5.93 to 35.06 ng m−3. The PAH emission in exposed schools was contributed mainly by traffic and industrial emissions, dependent on the source apportionment. The 95th percentiles of the incremental lifetime cancer risk estimated using Monte Carlo simulation revealed that the inhalation risk for the exposed children and comparative populations was 2.22 × 10−6 and 2.95 × 10−7, respectively. The degree of DNA injury was substantially more severe among the exposed children relative to the comparative community. This study reveals that higher exposure to PAHs increases the risk of genotoxic effects and cancer among children.

DNA damage in buccal cells in oral PMDs and malignant disorders by comet assay

Aim: DNA damage associated with Oral Squamous Cell Carcinoma (OSCC) and potentially malignant disorders (PMDs) is produced due to carcinogenic agents or increased oxidative stress. Comet assay can assist in early detection and evaluation of the amount of DNA damage; lymphocytesare the most commonly used cells for performing comet assay. Utilisation of buccal epithelial cells in comet assay can be a minimally invasive and rapid method. The present study compared the efficacy of comet assay in assessing DNA damage in buccal cells over peripheral blood leucocytes (PBLs) in oral potentially malignant and malignant disorders. Methods: The study included fifty five patients each of Leukoplakia, Oral Submucous Fibrosis (OSMF) and OSCC along with fifty five healthy individuals as control. Buccal epithelial cells were collected from all the selected subjects. DNA damage was evaluated bymeasuring the mean tail length (µm). Results: A significantly increased mean tail length (µm) and higher DNA damage were found in OSCC (26.1096 + 1.84355) and there was a progressive stepwise increase in mean tail length from control(8.4982 + 0.93307) to PMD [leukoplakia (14.6105 + 0.71857); OSMF (12.5009 + 1.12694)] to OSCC.The mean tail length in different habit groups was greater than controls, though no significant difference was noted between habit groups. The mean tail length of buccal cells was significantly greater than the mean tail length of PBLs in all study groups and controls. Conclusion: Hence, use of comet assay on buccal epithelial cells can prove to be beneficiary for evaluation of DNA damage.

A study of DNA damage in buccal cells of consumers of well- and/or tap-water using the comet assay: Assessment of occupational exposure to genotoxicants.

Because of concerns that natural aquifers in the region of Todos Santos (Baja California Sur, Mexico) might be contaminated by organochlorine pesticides and heavy metals, a case-control study was conducted among consumers and non-consumers of well- and/or tap-water to determine risks to human health. This study was based on a genotoxic evaluation of buccal cells using the Comet assay technique. Levels of DNA damage in the consumers group were significantly higher than those of the control group. However, occupational exposure to genotoxicants showed to be the critical factor rather than water consumption. Taking into account the professions of well- and/or tap-water consumers, agricultural workers exposed directly (those who fumigated) or indirectly (those not involved in fumigating) to agrochemicals showed greater genetic damage than controls. This difference persisted even when age, and whether the person smoked or consumed alcoholic drinks were considered. These factors were not associated with the level of genetic damage observed. Chemical analyses of organochlorine pesticides and heavy metals were carried out to evaluate the water quality of wells, faucets, and surface water of canals consumed by the population and/or used for irrigation. High concentrations of α and β endosulfan were detected in water of surface canals. Although our inventory of agrochemicals employed in the region showed the use of products considered carcinogenic and/or mutagenic, they were not detected by the analytical techniques used. Heavy metals (arsenic, mercury, and lead) were detected in water of some wells used for irrigation and human consumption. Environ. Mol. Mutagen. 58:619-627, 2017. © 2017 Wiley Periodicals, Inc.

Preliminary study of genotoxicity evaluation of orthodontic miniscrews on mucosa oral cells by the alkaline comet assay

Miniscrew implants are widely used nowadays in orthodontic treatments due to their good results in clinical practice. However, data regarding the biocompatibility of commercially available orthodontic miniscrews and temporary devices are very scarce, and their role as genotoxicity inducers has been not previously evaluated with the alkaline comet assay. The aim of this study was to investigate the DNA damage in buccal cells of patients subjected to orthodontic treatments. The alkaline comet assay has been applied in oral mucosa cells from patients treated with conventional orthodontic treatment in comparison to patients treated additionally with miniscrews, non-treated volunteers (control) and smoking volunteers (positive control). The application of orthodontic appliances and miniscrews induced significant and similar (2-fold) increases of %DNA in tail in comparison to control group. Females experienced a significant increase in %DNA in all the treatments in comparison to the control group, whereas males showed significant damage only with the combined orthodontic and miniscrew treatment. In conclusion, conventional orthodontic appliances induced genotoxicity, and the incorporation of miniscrews assayed did not imply any additional increase of DNA damage.

Genotoxicity of waterpipe smoke in buccal cells and peripheral blood leukocytes as determined by comet assay

Context: Waterpipe smoke causes DNA damage in peripheral blood leukocytes and in buccal cells of smokers.Objective: To determine the exposure effect of waterpipe smoke on buccal cells and peripheral blood leukocytes in regard to DNA damage using comet assay.Materials and methods: The waterpipe smoke condensates were analyzed by gas chromatography-mass spectrometry (GC-MS). The study was performed on 20 waterpipe smokers. To perform comet assay on bucaal cells of smokers, 10 µl of cell suspension was mixed with 85 µl of pre-warmed 1% low melting agarose, applied to comet slide and electrophoresed. To analyze the effect of smoke condensate in vitro, 1 ml of peripheral blood was mixed with 10 µl of smoke condensate and subjected for comet assay.Results: The GC-MS analysis revealed the presence of 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4on, nicotine, hydroxymethyl furancarboxaldehyde and 3-ethoxy-4-hydroxybenzaldehyde in the smoke condensates. Waterpipe smoking caused DNA damage in vivo in buccal cells of smokers. The tail moment and tail length in buccal cells of smokers were 186 ± 26 and 456 ± 71, respectively, which are higher than control. The jurak and moassel smoke condensates were found to cause DNA damage in peripheral blood leukocytes. The moassel smoke condensate was more damaging.Discussion: There is wide misconception that waterpipe smoking is not as harmful as cigarette smoking. This study demonstrated that waterpipe smoke induced DNA damage in exposed cells.Conclusion: Waterpipe smokes cause DNA damage in buccal cells. The smoke condensate of both jurak and moassel caused comet formation suggesting DNA damage in peripheral blood leukocytes.

Regular black tea habit could reduce tobacco associated ROS generation and DNA damage in oral mucosa of normal population

Tobacco and tea habit are very common in world wide. In the present study, an attempt was made to evaluate the effect of regular drinking of black tea on reactive oxygen species (ROS) generation and DNA damage in buccal cells of normal subjects with or without tobacco habit. Expression of ROS associated proteins IκB, NF-κB as well as DNA repair associated proteins p53, MLH1 were also analyzed. Exfoliated buccal cells were collected from 308 healthy individuals and classified according to age, tobacco and tea habits. In all age groups, comparatively high ROS level and significantly high DNA damage frequency were seen in individuals with tobacco habit than the subjects without tea and tobacco habits. Tea habit effectively lowered ROS level and restrict DNA damage in tobacco users irrespective of ages. The DNA damage seen in the subjects was not associated with apoptosis. Moreover, tea habit effectively lowered the expression of IκB, NF-κB, p53 and MLH1 in tobacco users in all age groups. It seems that regular black tea habit could have anti-genotoxic effect as revealed by reduced tobacco associated ROS generation and DNA damage in buccal cells.

Effect of Sample Collection and Storage Conditions on DNA Damage in Buccal Cells From Agricultural Workers

Effect of Sample Collection and Storage Conditions on DNA Damage in Buccal Cells From Agricultural Workers

Effects of sample collection and storage conditions on DNA damage in buccal cells from agricultural workers

Buccal cells are becoming a widely used tissue source for monitoring human exposure to occupational and environmental genotoxicants. A variety of methods exist for collecting buccal cells from the oral cavity, including rinsing with saline, mouthwash, or scraping the oral cavity. Buccal cells are also routinely cryopreserved with dimethyl sulfoxide (DMSO), then examined later for DNA damage by the comet assay. The effects of these different sampling procedures on the integrity of buccal cells for measuring DNA damage are unknown. This study examined the influence of the collection and cryopreservation of buccal cells on cell survival and DNA integrity. In individuals who rinsed with Hank's balanced salt solution (HBSS), the viability of leukocytes (90%) was significantly ( p < 0.01) greater than that of epithelial cells (12%). Similar survival rates were found for leukocytes (88%) and epithelial cells (10%) after rinsing with Listerine ® mouthwash. However, the viability of leukocytes after cryopreservation varied significantly ( p < 0.01) with DMSO concentration. Cell survival was greatest at 5% DMSO. Cryopreservation also influenced the integrity of DNA in the comet assay. Although tail length and tail moment were comparable in fresh or cryopreserved samples, the average head intensity for cryopreserved samples was ∼6 units lower (95% CI: 0.8–12 units lower) than for fresh samples ( t 25 = −2.36, p = 0.026). These studies suggest that the collection and storage of buccal samples are critical factors for the assessment of DNA damage. Moreover, leukocytes appear to be a more reliable source of human tissue for assessing DNA damage and possibly other biochemical changes.