Lactate Dehydrogenase Levels in the Saliva of Cigarette and E-Cigarette Smokers (Vapers): A Comparative Analysis

Alteration of salivary LPO, MDA, LDH, glutathione, GPx, SOD and vitamins in oral submucous fibrosis: A three-level meta-analysis study

This study aims to investigate the alteration of salivary biomarker profiling in the development of oral submucous fibrosis (OSMF) and to explore the influence of saliva in the diagnosis of OSMF. A systematic search of published articles using the PRISMA guidelines was conducted to identify relevant studies on OSMF and saliva. All eligible studies, including case-control, cross-sectional studies, cohort, and pilot studies, contained the evaluation of salivary biomarker profiling in patients with OSMF. Salivary biomarker data from 28 selected articles were categorized into nine groups, and their mean values were determined. A three-step meta-analysis was performed by grouping salivary biomarker profiling into more heterogeneous categories based on OSMF classification, considering functional, histological, and clinical grading. The salivary biomarker profiling analysis revealed significant alterations in all markers, indicating their efficacy in OSMF diagnosis. Subgroup analyses highlighted significant associations in oxidative stress and protein with increased mean values, particularly emphasizing lipid peroxidase (LPO), malondialdehyde (MDA), and lactate dehydrogenase (LDH). Conversely, decreased mean values were observed in glutathione, glutathione peroxidase (GPx), superoxide dismutase (SOD), and vitamins. Notably, OSMF grading analysis demonstrated a significant difference in weighted effect sizes for histological grading, particularly in stage IV. The study underscores the alteration of specific salivary biomarkers, particularly those associated with LPO, MDA, LDH, glutathione, GPx, SOD, and vitamins, in diagnosing and grading OSMF.

Impact of prolonged exposure to occasional and regular waterpipe smoke on cardiac injury, oxidative stress and mitochondrial dysfunction in male mice

Regular waterpipe smoking (Reg-WPS) is well recognized for its deleterious effect on the heart. However, there is a paucity of experimental studies on the impact of occasional waterpipe smoking (Occ-WPS), also known as nondaily smoking, versus Reg-WPS on cardiac homeostasis, and the mechanisms underlying these effects. Hence, we aimed, in the present study, to investigate the effect of Occ-WPS (30 min/day, 1 day/week) versus Reg-WPS (30 min/day, 5 days/week) for 6 months on systolic blood pressure (SBP), cardiac injury, oxidative markers, chemokines, proinflammatory cytokines, DNA damage and mitochondrial function compared with air (control) exposed mice. Our results show that SBP was increased following exposure to either Occ-WPS or Reg-WPS compared with air-exposed mice. Moreover, we found that only Reg-WPS induced a significant elevation in the levels of troponin I, brain natriuretic peptide, lactate dehydrogenase, and creatine phosphokinase. However, the atrial natriuretic peptide (ANP) was significantly increased in both Occ-WPS and Reg-WPS groups. Compared with air-exposed mice, the levels of lipid peroxidation, reduced glutathione and monocyte chemoattractant protein-1 were only significantly augmented in the Reg-WPS. However, catalase, superoxide dismutase, and CXCL1 were significantly increased in both Occ-WPS and Reg-WPS. The concentrations of the adhesion molecules E-selectin, vascular cell adhesion molecule-1, and intercellular adhesion molecule-1 were solely elevated in the heart of mice exposed to Reg-WPS. Similarly, the concentrations of interleukin-1β and tumor necrosis factor α were only significantly augmented in the Reg-WPS. However, both Occ-WPS and Reg-WPS triggered significant augmentation in the levels of IL17 and DNA damage compared to the control groups. Furthermore, while Occ-WPS induced a slight but statistically insignificant elevation in the concentrations of mammalian targets of rapamycin and nuclear factor erythroid-derived 2-like 2 (Nrf2) expression, Reg-WPS exposure increased their levels substantially, in addition to p53 and mitochondrial complexes II & III, and IV activities compared with air-exposed mice. In conclusion, our findings show that while the long-term Occ-WPS exposure induced an elevation of SBP, ANP, antioxidant enzymes, IL17, CXCL1, and cardiac DNA damage, Reg-WPS exposure was consistently associated with the elevation of SBP and occurrence of cardiac damage, inflammation, oxidative stress, DNA damage and mitochondrial dysfunction.

The use of E-cigarettes as a risk factor for oral potentially malignant disorders and oral cancer: a rapid review of clinical evidence

BACKGROUND

The popularity of e-cigarettes has increased rapidly in the last decade, particularly among teens and young adults, being advertised as a less harmful alternative to conventional tobacco products. However, in vitro and in vivo studies have evidenced a variable quantity of potentially harmful components and some recognized carcinogens which may cause DNA damage in oral cells. Additionally, evidence suggests that e-cigarettes may play active roles in the pathogenesis of other malignancies, such as lung and bladder cancers. Therefore, this rapid review aimed to assess the available clinical evidence about using e-cigarettes as a risk factor for oral potentially malignant disorders (OPMD) and oral cancer.

MATERIAL AND METHODS

A systematic search for English language articles published was performed in PubMed (MEDLINE), Embase, Scopus, and Web of Science. After the study selection process, the authors included twelve clinical studies about OPMD and oral cancer risk in e-cigarette users.

RESULTS

The main findings showed the presence of carcinogenic compounds in saliva and morphologic changes, DNA damage, and molecular pathways related to carcinogenesis in the oral cells of e-cigarette users. However, results were inconsistent compared to tobacco smokers and control groups.

CONCLUSIONS

the current clinical evidence on this topic is limited and insufficient to support using e-cigarettes as a risk factor for OPMD and oral cancer. Nevertheless, dental care professionals should advise patients responsibly about the potentially harmful effects of e-cigarettes on the oral mucosa cells. Future long-term and well-designed clinical studies are needed.

Utility of salivary biomarkers for diagnosis and monitoring the prognosis of nicotine addiction - A systematic review

Objectives

Tobacco and smoke associated with tobacco comprises of a mixture of more than 9500 chemical compounds, most of which have been identified as harmful. Two of the most potent carcinogens found in cigarette smoke are N'-nitrosonornicotine (NNN) and polycyclic aromatic hydrocarbons (PAHs). The most commonly used method to detect and monitor nicotine addiction is via serum cotinine levels. Though considered the gold standard, there is a decline in preventive screening and diagnostic testing due to the fear of pain from invasive testing.

Data sources and study selection

A structured literature search was performed using the search engines PubMed and Google scholar following the PRISMA guidelines for systematic reviews. The titles and abstracts were retrieved and analysed, followed by full-text relevant data extraction in addition to a risk-of-bias analysis.

Data extraction and synthesis

A total of 37 studies were included in the systematic review. Salivary cotinine levels were compared between smokers and non-smokers, cigarette smokers and water pipe smokers, water pipe smokers and non-smokers. Lactate dehydrogenase salivary levels were compared between smokers and non-smokers, and salivary thiocyanate were compared between smokers and non-smokers.

Conclusions

Identifying biomarkers with high performance in terms of sensitivity and specificity will contribute to accelerating future research in this domain.

DNA damage in human oral cells induced by use of e-cigarettes

The use of electronic cigarettes (e-cigarettes) has increased rapidly in the United States, especially among high school students. e-Cigarettes contain some recognized carcinogens and may induce DNA damage in oral cells. The aim of this review is to summarize studies reporting DNA adducts or other types of DNA damage in oral cells in vitro or in vivo upon exposure to e-cigarette vapor and to evaluate the possible connections between e-cigarette exposure and oral cancer. Three databases including PubMed, Scopus, and EMBASE and gray literature were searched for articles published up to April 24, 2022. After screening 321 articles, we extracted 27 for further investigation. Based on the inclusion criteria, 22 articles were eligible for this review. The in vitro studies demonstrate that e-cigarette liquid or vapor can induce DNA damage, oxidative stress, DNA double-stranded breaks, apoptosis, cytotoxicity, and genotoxicity in different types of oral cells. The clinical studies showed that e-cigarette users have significantly higher levels of N'-nitrosonornicotine, acrolein DNA adducts, metanuclear anomalies, gene regulation, and lactate dehydrogenase enzyme expression and significantly lower levels of apurinic/apyrimidinic sites than non-users. Comparison of micronuclei levels between e-cigarette users and non-users gave inconsistent results. e-Cigarettes are implicated in DNA damage to oral cells, but publications to date present limited evidence. Future studies with larger sample sizes are required to investigate the long-term consequences of e-cigarette use.

Effects of preoperative serum lactate dehydrogenase levels on long-term prognosis in elderly patients with hepatocellular carcinoma undergoing transcatheter arterial chemoembolization

Hepatic arterial chemoembolization is an effective treatment for primary hepatocellular carcinoma (HCC) and can improve the survival rate of patients. Nevertheless, the long-term prognosis of patients with HCC is not optimistic. In recent years, tumor humoral detection has attracted extensive attention and is expected to become the main examination method for early tumor screening. Studies have found that serum LDH is an indicator with effective potential to predict tumor proliferation and progression, such as pancreatic cancer, esophageal cancer, nasopharyngeal cancer, etc., but the relationship between this indicator and the prognosis of HCC is still unclear. The purpose of this study was to clarify the relationship between serum LDH and the prognosis of patients with HCC, so as to provide an important scientific basis for prognosis judgment of HCC.

Lactate Dehydrogenase: The Beacon of Hope?

Lactate dehydrogenase enzyme (LDH) helps in the conversion of glucose into pyruvic acid during aerobic glycolysis and is found in the cytoplasm of most cells in the human body. When oxidative stress occurs in the body, LDH may be released extracellularly and its level is usually indicative of the severity of tissue damage. LDH has proved to be an inestimably resourceful marker in early prediction of serious diseases involving extensive tissue or cellular damage. This short communication explores the potential of LDH as a salivary biomarker of cell injury and death.