Effects of Tobacco on Salivary Antioxidative and Immunologic Systems

Modifiable factors for benign salivary gland neoplasms: A Mendelian randomization study

BACKGROUND

Observational studies have found associations between smoking, alcohol, radiation, body mass index (BMI), periodontitis, and the hazard of benign salivary gland neoplasms (BSGNs). Nevertheless, the etiology of BSGNs remains unclear. This study aims to assess the causal association between these modifiable factors and the BSGNs.

METHODS

Genetic instruments associated with exposures at the genome-wide significance level were selected from corresponding genome-wide association studies. The summary statistics for BSGNs were obtained from the FinnGen consortium (2445 cases and 340,054 controls). The inverse variance-weighted method was used as the primary analysis, and several sensitivity analyses were performed to test the reliability.

RESULTS

Genetically predicted higher lifetime smoking index (odds ratio [OR] = 2.10, p = 0.012) and BMI (OR = 1.58, p = 2.29 × 10-5) were associated with elevated risk of BSGNs, whereas other exposures do not. Sensitivity analyses showed consistency. The causal effect of the lifetime smoking index became more significant after adjusting for BMI (OR = 2.89, p = 0.005) and alcohol consumption (OR = 2.49, p = 0.002). A slight negative association emerged for alcohol consumption with adjustment for cigarettes per day (OR = 0.53, p = 0.034) but disappeared when adjusting for cigarettes per day and BMI.

CONCLUSION

This study supports the independent causal role of lifetime smoking index and BMI in BSGNs risk.

Salivary Oxidative Stress and Antioxidant Capacity in Smokeless Tobacco (Naswar) Users

Background

Naswar, a smokeless tobacco product, commonly consumed in Pakistan, is associated with a 10-fold increase in the risk of oral cancer. However, little is known about Naswar's underlying toxicity mechanisms.

Objective

The current study aimed to investigate the effects of Naswar use on oral health and salivary parameters.

Methods

A case-control study was conducted among Naswar users (n=42) and age-matched healthy controls (n=42) in Pakistan in 2019. Participant data were collected using questionnaires. Decayed, missing, and filled teeth (DMFT) scores were computed during clinical examinations. Unstimulated whole saliva was collected to assess salivary flow rate, pH, and salivary total oxidative stress (TOS)/total antioxidant capacity (TAC) using commercially available kits. Participants' oral health parameters were compared between cases and controls using ANOVA.

Results

No significant differences were observed between the two groups in terms of age, oral health, and hygiene practices and mean DMFT score. Mean salivary pH and the salivary flow rate was significantly (p<0.001) higher in Naswar users (7.7 and 0.71 mL/minute, respectively) than in non-users (6.95 and 0.52 mL/minute, respectively). Although TOS and TAC were not significantly different between the groups, Naswar users generally had a higher TOS (51.6±42 µmol/L) and lower TAC (0.55±0.18 mmol/L) than non-users (TOS 45.5±38.2 µmol/L and TAC 0.57±0.17 mmol/L). Correlational analysis also revealed a significant positive correlation between DMFT score and Naswar use duration (r=0.796, p<0.001) and the number of dips/units consumed each day (r=0.515; p<0.001).

Conclusion

Habitual Naswar use is associated with increased salivary flow rate, pH, and TOS, and reduced TAC levels in Pakistani adults compared to non-users. The pro-oxidant changes may contribute toward deleterious effects of Naswar use including oral cancer.

Effects of tobacco product use on oral health and the role of oral healthcare providers in cessation: A narrative review

Tobacco use has detrimental effects on health, including oral health. The emergence and increasing popularity of newer tobacco and nicotine products make tobacco use one of the major public health problems in the world. Tobacco use increases the risk of oral diseases such as oral cancer, oral mucosal lesions, periodontal disease, and dental caries, among many other oral diseases and conditions. The dental office is an excellent venue for providing cessation intervention. However, there is a lack of knowledge and training in tobacco use prevention among dental professionals. More efforts are needed for smoking cessation interventions in the dental office. Smoking cessation interventions provided by oral healthcare providers include brief educational, behavioral, and pharmacological interventions. This review provides an overview of the ill effects of tobacco use on oral health and the role of oral healthcare providers in managing and preventing tobacco dependence.

Effect of Garlic Ethanol Extract Administration on Gluthatione Levels to Prevent Oxidative Stress in Smoker Rat Model

Background

Sickle Garlic (Allium sativum L.) is known as a spice native to western Asia has a strong antioxidant effect and revealed it functions as an antioxidant by increasing ROS-capture activity, cellular antioxidants, SOD, CAT, and GSH levels in cells. Cigarette smoke is very dangerous because it can cause serious illness and death. Cigarette smoke is a major source of exogenous ROS because its particles are high in free radicals. Smoking is also related to a decrease in the body's natural antioxidant levels. Glutathione (GSH) synthesis and expression were found to increase initially and then decrease after being exposed to cigarette smoke.

Objective

The aim of this study is; to analyze effect of garlic ethanol extract administration on gluthatione levels to prevent oxidative stress in smoker rat model.

Methods

This was a case-control study with a control group design, with 15 healthy rats (Rattus norvegicus, sp.) divided into three groups, KN untreated animals (control), K1 animals exposed to cigarette smoke for 40 days (smoker), and K2 animals exposed to cigarette smoke for 40 days and treated with Allium sativum 0.1 g per day for 40 days (smoker and Allium sativum L.). After 40 days of treatment, all animals, including the control, were sacrificed with 30 mg/IP ketamine injections, and the blood plasma were taken for examination.

Results

there were significant difference in glutathione levels between the treatment groups (K2) with the control group (KN) and the smokers group (K1) (p <0.05).

Conclusion

garlic ethanol extract administration can increase gluthatione levels and prevent oxidative stress in smoker rat model.

Flavor Classification/Categorization and Differential Toxicity of Oral Nicotine Pouches (ONPs) in Oral Gingival Epithelial Cells and Bronchial Epithelial Cells

Oral nicotine pouches (ONPs) are a modern form of smokeless tobacco products sold by several brands in the U.S., which comprise a significant portion of non-combustible nicotine-containing product (NCNP) sales to date. ONPs are available in various flavors and may contain either tobacco-derived nicotine (TDN) or tobacco-free nicotine (TFN). The growth in popularity of these products has raised concerns that flavored ONPs may cause adverse oral health effects and promote systemic toxic effects due to nicotine and other ONP by-products being absorbed into the circulatory system through oral mucosa. We hypothesized that flavored ONPs are unsafe and likely to cause oral and pulmonary inflammation in oral and respiratory epithelial cells. Before analyzing the effects of ONPs, we first classified ONPs sold in the U.S. based on their flavor and the flavor category to which they belonged using a wheel diagram. Human gingival epithelial cells (HGEP) were treated with flavored ONP extracts of tobacco (original, smooth), menthol (wintergreen and cool cider), and fruit flavor (americana and citrus), each from the TDN and TFN groups. The levels of ONP-induced inflammatory cytokine release (TNF-α, IL-6, and IL-8) by ELISA, cellular reactive oxygen species (ROS) production by CellRox Green, and cytotoxicity by lactate dehydrogenase (LDH) release assay in HGEP cells were assessed. Flavored ONP extracts elicited differential toxicities in a dose- and extract-dependent manner in HGEP cells 24 h post-treatment. Both fruit TDN and TFN extracts resulted in the greatest cytotoxicity. Tobacco- and fruit-flavored, but not menthol-flavored, ONPs resulted in increased ROS production 4 h post-treatment. Flavored ONPs led to differential cytokine release (TNF-α, IL-6, and IL-8) which varied by flavor (menthol, tobacco, or fruit) and nicotine (TDN vs. TFN) 24 h post-treatment. Menthol-flavored ONPs led to the most significant TNF-α release; fruit TFN resulted in the most significant IL-6 release; and fruit TDN and tobacco TFN led to the highest release of IL-8. Subsequently, human bronchial epithelial cells (16-HBE and BEAS-2B) were also treated with flavored ONP extracts, and similar assays were evaluated. Here, the lowest concentration treatments displayed increased cytotoxicity. The most striking response was observed among cells treated with spearmint and tobacco flavored ONPs. Our data suggest that flavored ONPs are unsafe and likely to cause systemic and local toxicological responses during chronic usage.

An assessment of unstimulated salivary flow rate, IgA and clinical oral dryness among active and passive smokers

OBJECTIVES

The aim of this study was to assess the impact of smoking on the whole salivary flow rate (SFR), IgA levels and clinical oral dryness (COD) among active and passive smokers.

MATERIAL AND METHODS

The participants were categorized as active smokers (N = 54) or passive smokers (N = 163). Saliva was collected in tubes and placed in ice storage at -70°C. Salivary IgA levels were assessed in duplication using the enzyme linked immunosorbent assay (ELISA) method. Following the saliva sample collection, the subjects were assessed for COD using the COD score, SFR and caries. Chi-square test, the t-test and ANOVA were employed to compare the clinical impact of the smoking status associated with specific variables (smoking status, number of cigarettes, active caries, gender, age, COD score, IgA level and SFR). A p-value of <0.05 was considered significant.

RESULTS

Two hundred and seventeen subjects with the mean age of 32.86±6.30 years, with 145 males (66.8%) and 72 females (33.2%), were included in the study. Among the active smokers, 88.8% were males compared to 11.2% females. The active smokers had the mean age of 32.52 years, a COD score of 1.43, an IgA level of 1.39 g/l, and a SFR of 0.37 ml/min. Among the passive smokers, 59.5% were males and 40.5% were females, with the mean age of 32.97 years, a COD score of 0.87 g/l, an IgA level of 1.47, and a SFR of 0.42 ml/min. Active caries showed a positive correlation with the number of cigarettes, with significance in the >35 years age group (p < 0.05).

CONCLUSIONS

The study demonstrated significant differences in SFR, IgA and COD scores among the active and passive smokers. The number of cigarettes had a negative impact on saliva production, IgA levels, the oral health status, and the progression of caries with respect to age and gender. Smoking potentially leads to xerostomia associated with active caries. Int J Occup Med Environ Health. 2022;35(1):39-51.

Ethanol- and Cigarette Smoke-Related Alternations in Oral Redox Homeostasis

Alcohol abuse as well as smoking cigarettes has been proven to negatively affect the oral environment. The aim of this work was to provide a systematic review of the literature on the influence of ethanol and cigarette smoking on oral redox homeostasis. A search was performed for scientific articles indexed in the PubMed, Medline and Web of Science databases. We identified 32,300 articles, of which 54 were used for the final review, including the results from 2000 to 2021. Among the publications used to write this article, n = 14 were related to the influence of alcohol consumption (clinical studies n = 6, experimental studies n = 8) and n = 40 were related to the influence of smoking (clinical studies n = 33, experimental studies n = 7) on oral redox homeostasis. The reviewed literature indicates that alcohol abusers and smokers are more likely to suffer from salivary gland dysfunction, as well as develop precancerous lesions due to DNA damage. Compared to alcohol abstainers and non-smokers, alcohol drinkers and smokers are also characterized by a deterioration in periodontal health measured by various indicators of periodontal status. In summary, alcohol abuse and smoking are associated with disrupted oral redox homeostasis, which may lead not only to tooth loss, but also contribute to various adverse effects related to mental health, digestive processes and chronic inflammation throughout the human body.

Salivary Markers in Relation to Oral Squamous Cell Carcinoma in Smokeless Tobacco Users: A Literature Review

Context: Nicotine and carcinogens are present in smokeless tobacco products. Oral, esophageal, and pancreatic cancers have been seen in Smokeless tobacco users. This article aims at reviewing the available literature and summarizing the application of salivary markers in smokeless tobacco users and their association with oral squamous cell carcinoma. Evidence Acquisition: The terms “saliva or salivary”, “markers or biomarkers”, “smokeless tobacco or Chewing tobacco or snuff”, and “oral cancer or oral carcinoma or oral squamous cell carcinoma” were searched in PubMed, MEDLINE, Google Scholar, and Google databases. Original and review English-written articles published over the past 20 years were reviewed, and the appropriate papers were chosen and intently studied. A data form designed by the author was used to write the proper results. Results: Our initial search identified 135 articles, 35 of which met the criteria for entering the final study and were contained for review. In summary, these studies described 20 markers found in the saliva of smokeless tobacco users linked to oral cancer. Conclusions: In this review study, some salivary markers such as cytokines, immunoglobulins, antioxidants, etc. were reviewed. In this review, it was shown that similar changes in these markers occur in patients with cancer and smokeless tobacco users. With the development of these diagnostic markers, these may be used as a screening tool for the early detection of cancer in smokeless tobacco users.