The influence of cigarette and qalyan (hookah) smoking on serum nitric oxide metabolite concentration

Waterpipe Use and Its Cardiovascular Effects: A Systematic Review and Meta-Analysis of Case-Control, Cross-Sectional, and Non-Randomized Studies

Approximately 100 million people globally smoke cigarettes, making it a significant and quickly spreading global tobacco epidemic. Substance use disorders are frequently evaluated by non-randomized studies. Tobacco use and its impacts on the cardiovascular system were the subjects of a comprehensive search across five electronic databases: Cochrane, MEDLINE, Scopus, Embase, and PubMed. The findings demonstrated that waterpipe smokers in comparison to non-smokers have immediate elevations in heart rate and blood pressure, lower levels of high-density lipoprotein, higher levels of low-density lipoprotein, higher levels of triglycerides, higher levels of fasting blood glucose, and a higher heart rate. Users of waterpipes and cigarettes had similar average heart rates, blood pressure, and lipid levels, with the exception that waterpipe smokers had greater total cholesterol. Smoking a waterpipe has significant negative effects on the cardiovascular system comparable to cigarette smoking, and non-randomized studies proved to yield substantial evidence related to its cardiovascular effects. Such study designs can be used to evaluate substance use and its cardiovascular impact.

Commonalities in Metabolic Reprogramming between Tobacco Use and Oral Cancer

Tobacco use is a major public health concern and is linked to myriad diseases, including cancer. The link between tobacco use and oral cancer, specifically, is very strong, making tobacco use one of the primary risk factors for oral cancer. While this association is well known, the underlying biochemical changes that result from tobacco use, and how this links to metabolic phenotypes of oral cancer, is not well understood. To address this knowledge gap, a combination of literature reviews and metabolomics studies were performed to identify commonalities in metabolic perturbations between tobacco use and oral cancers. Metabolomics analysis was performed on pooled reference urine from smokers and non-smokers, healthy and malignant oral tissues, and cultured oral cells with or without treatment of the well-known tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). Alterations in amino acid metabolism, carbohydrates/oxidative phosphorylation, fatty acid oxidation, nucleotide metabolism, steroid metabolism, and vitamin metabolism were found to be shared between tobacco use and oral cancer. These results support the conclusion that tobacco use metabolically reprograms oral cells to support malignant transformation through these pathways. These metabolic reprogramming events may be potential targets to prevent or treat oral cancers that arise from tobacco use.

Circulating markers of nitric oxide homeostasis and cardiometabolic diseases: insights from population-based studies

Emerging data suggest that impaired nitric oxide (NO) homeostasis has a key role in development of cardiometabolic disorders. The association between circulating levels of NO metabolites, i.e. nitrate and nitrite (NOx), and risk of chronic diseases has not yet been fully clarified. This work aims to address epidemiologic aspects of NO metabolism and discusses different physiologic and pathophysiologic conditions influencing circulating NOx. Further, cross-sectional associations of serum NOx with metabolic disorders are described and along the way, potential short-term and long-term power of serum NOx for predicting cardiometabolic outcomes are reviewed. Results from population-based studies show that circulating NOx is affected by aging, smoking habits, pregnancy, menopause status, thyroid hormones, and various pathologic conditions including type 2 diabetes, insulin resistance, hypertension, and renal dysfunction. Lifestyle factors, especially dietary habits, but also smoking habits and the degree of physical activity influence NO homeostasis and the circulating levels of NOx. Elevated serum NOx, due to increased iNOS activity, is associated with increased incidence of metabolic syndrome, different obesity phenotypes, and cardiovascular events.

Association of Activity Altering Genotypes - Tyr113His and His139Arg in Microsomal Epoxide Hydrolase Enzyme with Esophageal Squamous Cell Carcinoma

The study aimed to explore the relationship of microsomal epoxide hydrolase (mEH) exon 3 (Tyr113His) and exon 4 (His139Arg) polymorphisms and predicted mEH activity with esophageal squamous cell carcinoma (ESCC) risk. 482 histologically confirmed cases and equal number of matched controls were analyzed by polymerase chain reaction-restriction length polymorphism (PCR-RFLP). Conditional logistic regression models were used to examine the association of polymorphisms with ESCC. We noted exon 3 slow genotype (OR = 6.57; CI 3.43-12.57) as well as predicted low mEH activity (OR = 3.99; CI 2.32-6.85) was associated with the ESCC risk. Elevated ESCC risk estimates were seen in smokers independent of genotypes but the association was stronger among smokers with exon 3 variant (OR = 6.67; 3.29-13.53) and low activity (OR = 7.52; CI 3.46-16.37) genotypes. Positive family history of cancer synergistically increased ESCC risk in the individuals who harbored exon 3 (OR = 13.59; CI 5.63-32.81) or altered mEH activity genotypes (OR = 13.35; CI 5.10-34.94). Significant interaction was seen between mEH exon 3 and exon 4 genotypes (P = 0.006) and between predicted mEH activity and positive family history of cancer (P = 0.018). These findings suggest association of ESCC risk with mEH polymorphisms which get modified by tobacco smoking and positive family history of cancer.

Systematic review: the etiology of esophageal squamous cell carcinoma in low-income settings

Esophageal carcinoma causes over 380 000 deaths per year, ranking sixth worldwide in mortality amongst all malignancies. Globally, the squamous cell subtype is most common and accounts for 80% of esophageal cancers. Nonetheless, esophageal squamous cell carcinoma is much more poorly understood than esophageal adenocarcinoma, including what is driving such high prevalences, why it often presents in young patients, and shows such marked geographical delineations Areas covered: The current literature was searched for articles focusing on aetiopathogenesis of squamous cell esophageal carcinoma via a systematic review, particularly in low-resource settings. This was supplemented by papers of interest known to the authors. Expert commentary: Current putative mechanisms include polycyclic aromatic hydrocarbons, nitrosamines, acetaldehyde, cyclo-oxygenase-2 pathways, androgen and their receptor levels, as well as smoking & alcohol, micronutrient deficiencies and diet, mycotoxins, thermal damage, oral hygiene and microbiotal factors, inhaled smoke, viral infections such as HPV, and chronic irritative states. Etiology is likely multifactorial and varies geographically. Though smoking and alcohol play a predominant role in high-income settings, there is strong evidence that mycotoxins, diet and temperature effects may play an under-recognized role in low and middle-income settings.

Tobacco Smoking: Findings from 20 Years of the Tehran Lipid and Glucose Study

CONTEXT

Smoking is a global public health priority and accurate data of the local population is essential to improve the health policies against its use. Hence, this study aimed to summarize the important findings available on the prevalence of smoking and its association with non-communicable diseases, documented by one of the largest prospective community-based studies of Iran.

EVIDENCE ACQUISITION

All articles derived from the Tehran Lipid and Glucose Study (TLGS) in the last two decades, from the earliest publications until 30 January 2018 were reviewed for their findings on tobacco smoking.

RESULTS

The prevalence of smoking in non-diabetic adults ≥ 20 years increased between baseline (phase I, 1999 - 2001) and follow-up (phase V, 2008 - 2011) from 25.5% to 35.4% among men and from 3.4% to 6.8% among women. In TLGS adolescents (10 - 18 years) water pipe use increased between 2003 and 2005 from 35.5% to 40.9% among boys and from 19.7% to 26.1% among girls. Regarding health hazards, smoking in men was associated with increased risk of combined impaired fasting glucose/impaired glucose tolerance [hazard ratio (HR) 1.69; confidence interval (CI) 95% 1.15 - 2.48] and hypertension (HR 1.26; CI 95% 0.98 - 1.63). Moreover, men, even smoking less than 10 cigarettes per day, were at increased risk for cardiovascular diseases by HR 2.12 (CI 95% 1.14 - 3.95). For women, the risk of chronic kidney disease dramatically increased 5.74-fold (CI 95% 2.71 - 12.15) among smokers. In the whole population, smoking contributed to 7.7% of all-cause mortality with HR 1.75 (CI 95% 1.38 - 2.22). Other health aspects of tobacco smoke, including its impact on metabolic status, thyroid function, female reproductive system and life style have also been reviewed.

CONCLUSION

Considering hazards of smoking, there is the urgency for more effective preventive measures in Iran; emphasizing the need for further local studies on the hazards of smoking with special attention to women and adolescents and the independent hazards of water pipe use.

The Nitrate-Nitrite-Nitric Oxide Pathway: Findings from 20 Years of the Tehran Lipid and Glucose Study

CONTEXT

We describe here the contributions of the Tehran lipid and glucose study (TLGS) to understanding different aspects of the nitrate (NO3)-nitrite (NO2)-nitric oxide (NO) pathway in health and disease.

EVIDENCE ACQUISITION

All English-language documents from the TLGS, focused on NO pathway were searched using the PubMed, Scopus, and Embase databases.

RESULTS

Reference values of serum concentrations of NO metabolites (nitrate+nitrite or NOx) were 11.5 - 76.4, 10.1 - 65.6, and 10.3 - 66.8 μmol/L in men, women, and the total population, respectively. Circulating NOx was affected by age, smoking habits, menopause status, thyroid hormones, and various pathologic conditions. Elevated serum NOx was related to increased incidence of metabolic syndrome (odds ratio (OR) = 1.75, 95% confidence interval (CI) = 1.19 - 2.59), hypertriglyceridemic-waist phenotype (OR = 1.39, 95% CI = 1.05 - 1.93), chronic kidney disease (OR = 1.86, 95% CI = 1.10 - 3.14) in women, and cardiovascular disease (hazard ratio (HR) = 1.35, 95% CI = 1.01 - 1.80] in the total population. In participants with low vitamin C intake, higher intakes of NO2 (≥ 8.77 mg/d) were accompanied with increased risk of diabetes (HR = 2.43, 95% CI = 1.45 - 4.05). A decreased risk of hypertension (OR = 0.58, 95% CI = 0.33 - 0.98) and chronic kidney disease (OR = 0.50, 95% CI = 0.24 - 0.89) was observed in response to higher intakes of NO2.

CONCLUSIONS

Circulating NOx is associated with and could predict the risk of metabolic disorders in a general population. Moreover, dietary NO3/NO2 exposure from usual diets seems to contribute to development of noncommunicable diseases.

DNA Repair Gene XRCC1 and XPD Polymorphisms and Gastric Cancer Risk: A Case-Control Study Outcome from Kashmir, India

Coding polymorphisms in several DNA repair genes have been reported to affect the DNA repair capacity and are associated with genetic susceptibility to many human cancers, including gastric cancer. An understanding of these DNA repair gene polymorphisms might assess not only the risk of humans exposed to environmental carcinogens but also their responses to different therapeutical approaches, which target the DNA repair pathway. In the present study, polymorphic variants of two DNA repair genes, XRCC1 Arg399Gln and XPD Lys751Gln, were chosen to be studied in association with gastric cancer susceptibility in the Kashmiri population. A total of 180 confirmed cases of gastric cancer (GC) and 200 hospital-based controls from Government Shri Maharaja Hari Singh Hospital, Srinagar, were included in the study. The genotyping for XRCC1 and XPD genes was carried out by polymerase chain reaction-restriction fragment length polymorphism. We found that tobacco smoking is strongly associated with GC risk (OR = 25.65; 95% CI: 5.49–119.7). However, we did not find any association of polymorphism of XRCC1 Arg399Gln (OR = 1.56; 95% CI: 0.32–7.82) and XPD Lys751Gln (OR = 0.46; CI: 0.10–2.19) with GC risk in the study population. The combination of genotypes and gender stratification of XRCC1 and XPD genotypic frequency did not change the results. Consumption of large volumes of salt tea was also not associated with gastric cancer risk. Polymorphic variants of XRCC1 Arg399Gln and XPD Lys751Gln are not associated with the risk of gastric cancer in the Kashmiri population. However, replicative studies with larger sample size are needed to substantiate the findings.

Vitamin C intake modify the impact of dietary nitrite on the incidence of type 2 diabetes: A 6-year follow-up in Tehran Lipid and Glucose Study

BACKGROUND

There is no epidemiological study on the association between dietary nitrate (NO₃) and nitrite (NO₂) and intakes and the risk of type 2 diabetes (T2D).

OBJECTIVE

The aim of this study was therefore to examine the potential effect of dietary NO₃ and NO₂ on the occurrence of T2D.

DESIGN

This longitudinal study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS) on 2139 T2D-free adults, aged 20-70 years, followed for a median of 5.8 y. Dietary intakes of NO₃ and NO₂ were estimated using a 168-food items validate semi-quantitative food frequency questionnaire, at baseline. Multivariate Hazard Ratios (HR) and 95% confidence intervals (CI), adjusted for diabetes risk score (DRS), and dietary intakes of fat, fiber and vitamin C, were calculated for residual energy-adjusted NO₃ and NO₂ intakes. Since significant interaction (P = 0.024) was found between NO₂ and vitamin C intakes in the multivariable model, stratified analyses were done for < and ≥ median vitamin C intakes.

RESULTS

Median (inter quartile range; IQR) daily intake of NO₃ and NO₂ were 410 mg/d (343-499) and 8.77 mg/d (7.53-10.2). An increased risk of T2D was observed among participants who had higher intake of total and animal-based NO₂ in participants who had low vitamin C intake (HR = 2.43, 95% CI = 1.45-4.05, HR = 1.88, 95% CI = 1.12-3.15, respectively). We found no significant association between NO₃ in overall, and plant- and animal sources as well, with the risk of T2D. Plant-derived NO₂ was also unrelated to incidence of T2D.

CONCLUSION

Our findings indicated that higher intakes of total and animal-based NO₂ may be an independent dietary risk factor for development of T2D in subjects with lower vitamin C intakes.

Added value of total serum nitrate/nitrite for prediction of cardiovascular disease in middle east caucasian residents in Tehran

Data on the association between serum nitrate/nitrite and cardiovascular disease (CVD) is controversial; the aim of this study was to examine the potential utility of serum nitrate/nitrite in prediction of CVD. A total of 2443 adult participants, free from CVD at baseline were included. The probability of developing CVD was estimated by incorporating traditional CVD risk factors into a logistic regression model in the presence of serum nitrate/nitrite. The probability of CVD was calculated using Ln-transformed CVD risk factors as a covariate in the presence of Ln-transformed nitrate/nitrite in the final model. The added value of nitrate/nitrite was estimated using receiver operating characteristic curves and the net reclassification index (NRI). During follow-up, 169 events occurred. The multivariate odds ratio (95% confidence interval) for each 1 unit of increase in the Ln-transformed traditional risk factors and Ln-transformed nitrate/nitrite, were 3.20 (2.67-3.84) and 1.35 (1.01-1.80) for incident CVD, respectively. The areas under the curves of discrimination for models with and without nitrate/nitrite were not significantly different; however, incorporating nitrate/nitrite to the traditional CVD risk model can help appropriately reclassify over 6% of individuals at risk. In conclusion, serum nitrate/nitrite levels were independently associated with incident CVD. Measurement of serum nitrate/nitrite provided information beyond individual data on risk factors and improved prediction of CVD.

A review of the health effects of smoking shisha

There is emerging evidence, although at early stages, of various detrimental health effects after smoking shisha. With regard to the cardiovascular system, there is a significant acute rise in cardiovascular markers, such as heart rate and blood pressure. The long-term effects on the cardiovascular system are yet to be established. Shisha smoking has also been significantly associated with lung cancer. Various other forms of cancer have also been documented, but have not reached statistical significance and require further research. Finally, shisha smoking increases the risk of infection and has been associated with outbreaks in the Middle East. Therefore, with the increasing consumption of shisha in Europe, especially in the UK, more research is required to tackle this potential public health threat.

Harmful effects of shisha: literature review

Tobacco is a preventable cause of morbidity and mortality across the world. A recently infamous way of smoking tobacco is shisha. Shisha smoking is also known as water pipe, hookah and Narghile smoking. The percentage of shisha smokers is on the rise rapidly spanning the globe. A literature review was conducted to identify all evidence on the epidemiological variations and health effects of shisha smoking. “Pub med” is used as a searching tool to identify all relevant empirical studies conducted worldwide. A qualitative overview of evidence is presented.

Exposure to Shisha smoking is significantly associated with low infant weight, heart rate variations, hyperglycemia and hypertriglyceridemia. Increased risk of carcinoma is also leagued with it including carcinomas of the pancreas and lung being at the forefront. In conclusion, this review identifies grounds of several adverse conditions being associated with the habit of shisha smoking. It also evaluates the relevant epidemiological variations around the globe. The review culminates in the importance of enlightening shisha smokers regarding its deleterious effects.

In vitro effects of waterpipe smoke condensate on endothelial cell function: a potential risk factor for vascular disease

AIM

Despite its increasing popularity, little is known about the health effects of waterpipe smoking (WPS), particularly on the cardiovascular system. To investigate the role of WPS as a risk factor for vascular disease, we evaluated its effect on endothelial cell function, which is an early event in vascular disease pathogenesis. We assessed the changes in cell viability, ROS generation, inflammatory and vasodilatory markers and in vitro angiogenesis of human aortic endothelial cells in response to waterpipe smoke condensate exposure.

METHODS AND RESULTS

Mainstream waterpipe smoke condensate (WSC) was generated using a standard laboratory machine protocol. Compared to control, WSC induced cell cycle arrest, apoptosis, and oxidative stress in human primary endothelial cells. In addition, we assayed for impaired endothelium-dependent vasodilation and induced inflammation by studying the effect of WPS on the content and activity of AMPK, eNOS proteins and NF-κB p65 ser536 phosphorylation, respectively. WSC inhibited AMPK/eNOS phosphorylation and induced phosphorylation of p65. Moreover, we evaluated endothelial cells repair mechanism related properties that include migration/invasion and in vitro tube formation upon treatment with WSC. WSC reduced the motility and inhibited angiogenic potential of HAEC cells.

CONCLUSIONS

WPS induced endothelial cell dysfunction as evident by exerting oxidative stress, inflammation, and impaired endothelial vasodilatory function and repair mechanisms. All together these data provide evidence for the potential contribution of WPS to endothelial dysfunction and thus to vascular disease.

Smoking water-pipe, chewing nass and prevalence of heart disease: a cross-sectional analysis of baseline data from the Golestan Cohort Study, Iran

OBJECTIVE

Water-pipe and smokeless tobacco use have been associated with several adverse health outcomes. However, little information is available on the association between water-pipe use and heart disease (HD). Therefore, we investigated the association of smoking water-pipe and chewing nass (a mixture of tobacco, lime and ash) with prevalent HD.

DESIGN

Cross-sectional study.

SETTING

Baseline data (collected in 2004-2008) from a prospective population-based study in Golestan Province, Iran.

PARTICIPANTS

50 045 residents of Golestan (40-75 years old; 42.4% men).

MAIN OUTCOME MEASURES

ORs and 95% CIs from multivariate logistic regression models for the association of water-pipe and nass use with HD prevalence.

RESULTS

A total of 3051 (6.1%) participants reported a history of HD, and 525 (1.1%) and 3726 (7.5%) reported ever water-pipe or nass use, respectively. Heavy water-pipe smoking was significantly associated with HD prevalence (highest level of cumulative use vs never use, OR=3.75; 95% CI 1.52 to 9.22; p for trend=0.04). This association persisted when using different cut-off points, when restricting HD to those taking nitrate compound medications, and among never cigarette smokers. There was no significant association between nass use and HD prevalence (highest category of use vs never use, OR=0.91; 95% CI 0.69 to 1.20).

CONCLUSIONS

Our study suggests a significant association between HD and heavy water-pipe smoking. Although the existing evidence suggesting similar biological consequences of water-pipe and cigarette smoking make this association plausible, results of our study were based on a modest number of water-pipe users and need to be replicated in further studies.

Hookah smoking, nass chewing, and oesophageal squamous cell carcinoma in Kashmir, India

BACKGROUND

Although cigarette smoking is an established risk factor for oesophageal squamous cell carcinoma (ESCC), there is little information about the association between other smoking and smokeless tobacco products, including hookah and nass, and ESCC risk. We conducted a case-control study in Kashmir Valley, India, where hookah smoking, nass chewing, and ESCC are common, to investigate the association of hookah smoking, nass use, and several other habits with ESCC.

METHODS

We recruited 702 histologically confirmed ESCC cases and 1663 hospital-based controls, individually matched to the cases for age, sex, and district of residence from September 2008 to January 2012. Conditional logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs).

RESULTS

Ever-hookah smoking (OR=1.85; 95% CI, 1.41-2.44) and nass chewing (OR=2.88; 95% CI, 2.06-4.04) were associated with ESCC risk. These associations were consistent across different measures of use, including intensity, duration, and cumulative amount of use, and after excluding ever users of the other product and cigarette smokers. Our results also suggest an increased risk of ESCC associated with ever-gutka chewing and -bidi smoking. However, the latter associations were based on small number of participants.

CONCLUSION

This study shows that hookah and nass use are associated with ESCC risk. As prevalence of hookah use seems to be increasing among young people worldwide, these results may have relevance not only for the regions in which hookah use has been a traditional habit, but also for other regions, including western countries.

Plasma and exhaled breath condensate nitrite-nitrate level in relation to environmental exposures in adults in the EGEA study

This study evaluated the associations between biological markers in the nitrate-nitrite-NO pathway and four environmental exposures among subjects examined in the second survey (2003-2007) of the French Epidemiological study on Genetics and Environment of Asthma (EGEA). Total nitrite and nitrate (NO(2)(-) /NO(3)(-)) levels were measured both in plasma and in exhaled breath condensate (EBC) in 949 adults. Smoking, diet and exposure to chlorine products were assessed using standardized questionnaires. Exposure to air pollutants was estimated by using geostatistical models. All estimates were obtained with generalized estimating equations for linear regression models. Median levels of NO(2)(-)/NO(3)(-) were 36.3 μM (1st-3rd quartile: 25.7, 51.1) in plasma and 2.0 μmol/mg proteins (1st-3rd quartile 0.9, 3.9) in EBC. After adjustment for asthma, age, sex and menopausal status, plasma NO(2)(-)/NO(3)(-) level increased with leafy vegetable consumption (above versus below median=0.04 (95%CI: 0.001, 0.07)) and decreased in smokers (versus non/ex-smokers=-0.08 (95%CI: -0.11, -0.04). EBC NO(2)(-)/NO(3)(-) level decreased in smokers (-0.08 (95%CI: -0.16, -0.001)) and with exposure to ambient O(3) concentration (above versus below median=-0.10 (95%CI: -0.17, -0.03)). Cured meat, chlorine products, PM(10) and NO(2) concentrations were not associated with NO(2)(-)/NO(3)(-) levels. Results suggest that potential modifiable environmental and behavioral risk factors may modify NO(2)(-)/NO(3)(-) levels in plasma and EBC according to the route of exposure.

Acute effects of waterpipe tobacco smoking: a double-blind, placebo-control study

BACKGROUND

Waterpipe tobacco smoking usually involves heating flavored tobacco with charcoal and inhaling the resulting smoke after it has passed through water. Waterpipe tobacco smoking increases heart rate and produces subjective effects similar to those reported by cigarette smokers. These responses are thought to be nicotine-mediated, though no placebo-control studies exist. Accordingly, this double-blind, placebo-control study compared the acute physiological and subjective effects of waterpipe tobacco smoking to those produced when participants used a waterpipe to smoke a flavor-matched, tobacco-free preparation.

METHODS

Occasional waterpipe tobacco smokers (n = 37; 2-5 monthly smoking episodes for ≥ 6 months) completed two double-blind, counterbalanced sessions that differed by product: preferred brand/flavor of waterpipe tobacco or flavor-matched, tobacco-free preparation. For each 45-min, ad lib smoking episode blood and expired air CO were sampled, cardiovascular and respiratory response were measured, and subjective response was assessed.

RESULTS

Waterpipe tobacco smoking significantly increased mean (± SEM) plasma nicotine concentration (3.6 ± 0.7 ng/ml) and heart rate (8.6 ± 1.4 bpm) while placebo did not (0.1 ± 0.0 ng/ml; 1.3 ± 0.9b pm). For carboxyhemoglobin (COHb) and expired air CO, significant increases were observed for tobacco (3.8 ± 0.4%; 27.9 ± 2.6 ppm) and for placebo (3.9 ± 0.4%; 27.7 ± 3.3 ppm) with no differences across condition. Independent of condition, symptoms of nicotine/tobacco abstinence (e.g., "urges to smoke", "anxious") were reduced and direct effects (e.g., "dizzy", "satisfy") increased.

DISCUSSION

These results from the first placebo-control study of waterpipe tobacco smoking demonstrate that waterpipe-induced heart rate increases are almost certainly mediated by nicotine though the subjective effects observed in these occasional smokers were not.

Oxidative stress impairs endothelial nitric oxide levels in Behçets' disease

BACKGROUND

Behçet's disease (BD) is an inflammatory vasculitis. Endogenous nitric oxide (NO), produced by endothelial cells, has pleiotropic effects such as vasodilatator, antiplatelet, antiproliferative. Reactive oxygen species (ROS) are produced at sites of endothelial inflammation. ROS target polyunsaturated lipids, which results in malondialdehyde (MDA) production.

OBJECTIVE

The aim was to investigate the oxidative stress in BD patients by measuring MDA and total antioxidant status (TAS) levels and to establish a possible relationship with respect to NO levels regarding disease activity.

MATERIALS AND METHODS

55 BD patients (30 active/25 inactive) and 20 healthy volunteers were included in the study. Blood samples were drawn following an overnight fasting. TAS and MDA levels were determined spectrophotometrically. Serum nitrite (NO(2-)) and nitrate (NO(3-)) levels were measured to estimate NO production. Data were expressed as mean ± SD.

RESULTS

TAS levels were significantly lower in BD patients than the controls (1.19 ± 0.34 vs. 3.29 ± 0.89 mmol/L). In the active BD group, MDA levels (0.36 ± 0.19 nmol/mL) were significantly higher than both the inactive BD group (0.25 ± 0.18 nmol/mL) and controls (0.18 ± 0.41 nmol/mL). NO levels were significantly lower in the active group compared to the inactive group (18.0 ± 2.80 vs. 19.40 ± 2.70 µmol/L). MDA levels correlated negatively with NO levels in the active group.

CONCLUSION

Decreased NO levels mediated by increased oxidative stress significantly contribute to endothelial dysfunction observed in BD.

Smoke exposure and circulating progenitor cells: evidence for modulation of antioxidant enzymes and cell count

BACKGROUND

Cigarette smoking is involved in vascular inflammation and impairment of circulating progenitor cells (CPCs), including endothelial progenitor cells (EPCs). The study aim was to evaluate the redox balance of these cells in relation to smoking exposure.

METHODS

Circulating cells from 36 healthy smokers and 26 controls were isolated and identified by flow cytometry. ROS generation, mRNA and protein cell expression, and enzymatic activity of MnSOD, catalase, and GPx-1 were evaluated.

RESULTS

Smokers showed higher levels of CRP and fibrinogen and lower levels of HDL-C. ROS and MnSOD were higher (p<0.001), while catalase and GPx-1 were lower (p<0.001) as was EPC number (p<0.001) in smokers. CPC and EPC correlated with HDL-C, CRP, ROS and enzyme expression and activity.

CONCLUSIONS

Our data suggest that smoking exposure involves antioxidant enzymes in CPCs and EPCs and that the inflammatory response in smokers plays an important role in impairing cells and their antioxidant functions.

Blood and urine cadmium, blood pressure, and hypertension: a systematic review and meta-analysis

BACKGROUND

Cadmium exposure has been inconsistently related to blood pressure.

OBJECTIVES

We updated and reevaluated the evidence regarding the relationships of blood cadmium (BCd) and urine cadmium (UCd) with blood pressure (BP) and hypertension (HTN) in nonoccupationally exposed populations.

DATA SOURCES AND EXTRACTION

We searched PubMed and Web of Science for articles on BCd or UCd and BP or HTN in nonoccupationally exposed populations and extracted information from studies that provided sufficient data on population, smoking status, exposure, outcomes, and design.

DATA SYNTHESIS

Twelve articles met inclusion criteria: eight provided data adequate for comparison, and five reported enough data for meta-analysis. Individual studies reported significant positive associations between BCd and systolic BP (SBP) among nonsmoking women [ß = 3.14 mmHg per 1 μg/L untransformed BCd; 95% confidence interval (CI), 0.14-6.14] and among premenopausal women (ß = 4.83 mmHg per 1 nmol/L log-transformed BCd; 95% CI, 0.17-9.49), and between BCd and diastolic BP (DBP) among women (ß = 1.78 mmHg comparing BCd in the 90th and 10th percentiles; 95% CI, 0.64-2.92) and among premenopausal women (ß = 3.84 mmHg per 1 nmol/L log-transformed BCd; 95% CI, 0.86-6.82). Three meta-analyses, each of three studies, showed positive associations between BCd and SBP (p = 0.006) and DBP (p < 0.001) among women, with minimal heterogeneity (I² = 3%), and a significant inverse association between UCd and HTN among men and women, with substantial heterogeneity (I² = 80%).

CONCLUSION

Our results suggest a positive association between BCd and BP among women; the results, however, are inconclusive because of the limited number of representative population-based studies of never-smokers. Associations between UCd and HTN suggest inverse relationships, but inconsistent outcome definitions limit interpretation. We believe a longitudinal study is merited.