Oxidative Stress is Closely Associated with Increased Arterial Stiffness, Especially in Aged Male Smokers without Previous Cardiovascular Events: A Cross-Sectional Study

Arterial stiffness and hypertension

Arterial stiffness and hypertension are closely related in pathophysiology. Chronic high blood pressure (BP) can lead to arterial wall damage by mechanical stress, endothelial dysfunction, increased inflammation, oxidative stress, and renin-angiotensin-aldosterone system (RAAS) activation. Hypertension also increases collagen fiber production and accelerates elastin fiber degradation. Stiffened arteries struggle with BP changes, raising systolic BP and pulse pressure. The resulting increased systolic pressure further hardens arteries, creating a harmful cycle of inflammation and calcification. Arterial stiffness data can predict target organ damage and future cardiovascular events in hypertensive patients. Thus, early detection of arterial stiffness aids in initiating preventive measures and treatment plans to protect against progression of vascular damage. While various methods exist for measuring arterial stiffness, pulse wave velocity is a non-invasive, simple measurement method that maximizes effectiveness. Healthy lifestyle changes, RAAS blockers, and statins are known to reduce arterial stiffness. Further research is needed to ascertain if improving arterial stiffness will enhance prognosis in hypertensive patients.

Cumulative Cigarette Consumption is Associated with Cardio-Ankle Vascular Index (CAVI) Mediated by Abdominal Obesity Assessed by A Body Shape Index (ABSI): A Cross-Sectional Study

AIM

To elucidate the mechanism by which cigarette smoking causes vascular damage, we examined the relationship between cumulative cigarette consumption and abdominal obesity, and the possible mediating effect of smoking on arterial stiffness.

METHODS

Cross-sectional data from 19499 never smokers and 5406 current smokers receiving health screening was analyzed. Abdominal obesity was assessed by ABSI, and arterial stiffness by CAVI. High CAVI was defined as CAVI ≥ 9.0.

RESULTS

Current smoker showed higher ABSI than never smokers after propensity score matching. Cumulative cigarette consumption expressed in pack-years correlated with ABSI (Rs: 0.312 in men, 0.252 in women), and was also extracted as an independent factor associated with ABSI by multiple regression analysis. A linear relationship between pack-year and CAVI was observed (Rs: 0.544 in men, 0.423 in women). Pack-year had almost equal discriminatory power in predicting high CAVI in both sexes (C-statistic: 0.774 in men, 0.747 in women), and the best cut-offs of pack-year for high CAVI were 24.5 in men and 14.7 in women. Bivariate logistic regression models revealed that the association between pack-year higher than cut-off and high CAVI was independent of traditional risks. A mediating effect of ABSI (mediation rate: 9.9% in men and 11.2% in women), but not waist circumference (WC), on the association of pack-year with CAVI was observed, after adjusting for traditional risks.

CONCLUSION

Cumulative cigarette smoking in pack-years was independently associated with ABSI. ABSI partially mediates the association between pack-year and CAVI, suggesting that abdominal obesity partially mediates smoking-related vascular dysfunction.

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.

The Effects of Smoking on the Diagnostic Characteristics of Metabolic Syndrome: A Review

Metabolic syndrome is a growing epidemic that increases the risk for cardiovascular disease, diabetes, stroke, and mortality. It is diagnosed by the presence of three or more of the following risk factors: 1) obesity, with an emphasis on central adiposity, 2) high blood pressure, 3) hyperglycemia, 4) dyslipidemia, with regard to reduced high-density lipoprotein concentrations, and 5) dyslipidemia, with regard to elevated triglycerides. Smoking is one lifestyle factor that can increase the risk for metabolic syndrome as it has been shown to exert negative effects on abdominal obesity, blood pressure, blood glucose concentrations, and blood lipid profiles. Smoking may also negatively affect other factors that influence glucose and lipid metabolism including lipoprotein lipase, adiponectin, peroxisome proliferator-activated receptors, and tumor necrosis factor-alpha. Some of these smoking-related outcomes may be reversed with smoking cessation, thus reducing the risk for metabolic disease; however, metabolic syndrome risk may initially increase post cessation, possibly due to weight gain. Therefore, these findings warrant the need for more research on the development and efficacy of smoking prevention and cessation programs.

Handgrip strength is inversely associated with augmentation index in patients with type 2 diabetes

Handgrip strength (HGS) is a measure of overall skeletal muscle strength and is used to identify risks for cardiovascular disease and mortality. Furthermore, HGS is an indicator of arterial stiffness that leads to atherosclerotic cardiovascular disease. This study aimed to examine the relationship between HGS and augmentation index (AIx) in patients with type 2 diabetes. A cross-sectional study was conducted to examine patients with type 2 diabetes whose HGS and AIx were measured in our hospital. AIx was measured noninvasively using an applanation tonometer, and multiple regression analyses were conducted to assess the independent relationship between HGS and AIx. This study included 404 patients. After adjusting for age, gender, body mass index, duration of diabetes, smoking and exercise habit, biochemical parameters, and physiological parameters related to arterial stiffness, HGS was found to be independently and inversely associated with AIx (β = - 0.270, p = 0.006). HGS was independently and inversely associated with AIx in patients with type 2 diabetes. Patients with diminished HGS should be subjected to intensive exercise therapy for reducing the risk of arterial stiffness and cardiovascular disease.Trial registration: UMIN000023010.

Examination of Large Artery Atherosclerosis could Reveal Small Artery Retinopathy in Untreated Middle-Aged Individuals

AIMS

Small arteries can be visualized in the ocular fundus, and findings of retinopathy based on Scheie classification are often applied to evaluate the impact of hypertension and atherosclerosis. However, the relationship between damage in the large and small arteries has not been investigated sufficiently, especially in the early stages. The present study investigated possible associations between large artery atherosclerosis and small artery retinopathy in untreated middle-aged individuals.

METHODS

Untreated middle-aged workers undergoing periodic health check-ups (n=7,730, 45±8 years) were enrolled in this study. The absence or presence and extent of retinopathy were characterized by ophthalmologists as hypertensive (H0-4) and atherosclerotic grades (S0-4) based on Scheie classification. Large artery atherosclerosis was examined based on functional assessment of the cardio-ankle vascular index (CAVI) and morphological assessment of the carotid intima-media thickness (IMT) by ultrasound.

RESULTS

We found significant differences in CAVI and carotid IMT between individuals with and without hypertensive or atherosclerotic retinopathy. Multivariable regression analysis showed that the presence of hypertensive and atherosclerotic retinopathy was significantly associated with CAVI and carotid IMT. Logistic regression analysis with the endpoint of a hypertensive or atherosclerotic lesion revealed that CAVI and carotid IMT are independent determinants of retinopathy.

CONCLUSIONS

CAVI and carotid IMT were significantly associated with the presence of retinopathy based on Scheie classification in untreated middle-aged subjects, implying that atherosclerotic examination in large arteries could reveal early-stage small artery retinopathy.

A body shape index could serve to identify individuals with metabolic syndrome and increased arterial stiffness in the middle-aged population

BACKGROUND

A body shape index (ABSI) is a novel anthropometric measure calculated using waist circumference (WC), body mass index (BMI), and body height. This study investigated the usefulness of ABSI to identify individuals with metabolic syndrome (MetS) and increased arterial stiffness in the middle-aged population.

METHODS

Middle-aged workers who underwent periodic health check-ups and who were without previous cardiovascular events were enrolled (n = 10,182). In addition to ABSI, visceral fat area (VFA) was evaluated using computed tomography. Obesity and MetS were diagnosed on the basis of WC, VFA, and ABSI. Arterial stiffness was examined by measuring the cardio-ankle vascular index (CAVI).

RESULTS

ABSI was significantly associated with CAVI in multivariable regression analysis. Logistic regression analysis revealed that ABSI was independently associated with the presence of MetS diagnosed on the basis of WC or VFA after adjustment for potential confounders, including BMI. Subjects with MetS diagnosed on the basis of each obesity index showed higher CAVI values than those without. Among subjects with MetS diagnosed on the basis of WC or VFA, those with MetS who met the definition of ABSI obesity showed significantly higher CAVI than those who did not. The other logistic regression analysis demonstrated that CAVI was independently associated with MetS defined on the basis of ABSI.

CONCLUSIONS

ABSI was significantly associated with CAVI and the presence of MetS in the middle-aged population and helped to discriminate individuals with MetS and increased CAVI. ABSI could serve to identify individuals with MetS and increased arterial stiffness.

Uric Acid in Inflammation and the Pathogenesis of Atherosclerosis

Hyperuricemia is a common metabolic syndrome. Elevated uric acid levels are risk factors for gout, hypertension, and chronic kidney diseases. Furthermore, various epidemiological studies have also demonstrated an association between cardiovascular risks and hyperuricemia. In hyperuricemia, reactive oxygen species (ROS) are produced simultaneously with the formation of uric acid by xanthine oxidases. Intracellular uric acid has also been reported to promote the production of ROS. The ROS and the intracellular uric acid itself regulate several intracellular signaling pathways, and alterations in these pathways may result in the development of atherosclerotic lesions. In this review, we describe the effect of uric acid on various molecular signals and the potential mechanisms of atherosclerosis development in hyperuricemia. Furthermore, we discuss the efficacy of treatments for hyperuricemia to protect against the development of atherosclerosis.

Inflammatory Mechanisms Contributing to Endothelial Dysfunction

Maintenance of endothelial cell integrity is an important component of human health and disease since the endothelium can perform various functions including regulation of vascular tone, control of hemostasis and thrombosis, cellular adhesion, smooth muscle cell proliferation, and vascular inflammation. Endothelial dysfunction is encompassed by complex pathophysiology that is based on endothelial nitric oxide synthase uncoupling and endothelial activation following stimulation from various inflammatory mediators (molecular patterns, oxidized lipoproteins, cytokines). The downstream signaling via nuclear factor-κB leads to overexpression of adhesion molecules, selectins, and chemokines that facilitate leukocyte adhesion, rolling, and transmigration to the subendothelial space. Moreover, oscillatory shear stress leads to pro-inflammatory endothelial activation with increased monocyte adhesion and endothelial cell apoptosis, an effect that is dependent on multiple pathways and flow-sensitive microRNA regulation. Moreover, the role of neutrophil extracellular traps and NLRP3 inflammasome as inflammatory mechanisms contributing to endothelial dysfunction has recently been unveiled and is under further investigation. Consequently, and following their activation, injured endothelial cells release inflammatory mediators and enter a pro-thrombotic state through activation of coagulation pathways, downregulation of thrombomodulin, and an increase in platelet adhesion and aggregation owing to the action of von-Willebrand factor, ultimately promoting atherosclerosis progression.

Cigarette Smoking Is Related to Endothelial Dysfunction of Resistance, but Not Conduit Arteries in the General Population-Results From the Gutenberg Health Study

Aims: Cigarette smoking is one of the most complex and least understood cardiovascular risk factors. Importantly, differences in the tobacco-related pathophysiology of endothelial dysfunction, an early event in atherogenesis, between circulatory beds remain elusive. Therefore, this study evaluated how smoking impacts endothelial function of conduit and resistance arteries in a large population-based cohort.

Methods and results: 15,010 participants (aged 35–74 years) of the Gutenberg Health Study were examined at baseline from 2007 to 2012. Smoking status, pack-years of smoking, and years since quitting smoking were assessed by a computer-assisted interview. Endothelial function of conduit and resistance arteries was determined by flow-mediated dilation (FMD) of the brachial artery, reactive hyperemia index (RHI) using peripheral arterial tonometry, as well as by reflection index (RI) derived from digital photoplethysmography, respectively. Among all subjects, 45.8% had never smoked, 34.7% were former smokers, and 19.4% were current smokers. Mean cumulative smoking exposure was 22.1 ± 18.1 pack-years in current smokers and mean years since quitting was 18.9 ± 12.7 in former smokers. In multivariable linear regression models adjusted for typical confounders, smoking status, pack-years of smoking, and years since quitting smoking were independently associated with RHI and RI, while no association was found for FMD. Overall, no clear dose-dependent associations were observed between variables, whereby higher exposure tended to be associated with pronounced resistance artery endothelial dysfunction.

Conclusions: Cigarette smoking is associated with altered endothelial function of resistance, but not conduit arteries. The present results suggest that smoking-induced endothelial dysfunction in different circulatory beds may exhibit a differential picture.

Analytical evaluation of serum non-transferrin-bound iron and its relationships with oxidative stress and cardiac load in the general population

Excessive iron accumulation provokes toxic effects, especially in the cardiovascular system. Under iron overload, labile free non-transferrin-bound iron (NTBI) can induce cardiovascular damage with increased oxidative stress. However, the significance of NTBI in individuals without iron overload and overt cardiovascular disease has not been investigated. We aimed to examine the distribution of serum NTBI and its relationship with oxidative stress and cardiac load under physiological conditions in the general population.We enrolled individuals undergoing an annual health check-up and measured serum NTBI and derivatives of reactive oxygen metabolites (d-ROM), an oxidative stress marker. In addition, we evaluated serum levels of B-type natriuretic peptide (BNP) to examine cardiac load. We excluded patients with anemia, renal dysfunction, cancer, active inflammatory disease, or a history of cardiovascular disease.A total of 1244 individuals (57.8 ± 11.8 years) were enrolled, all of whom had detectable serum NTBI. d-ROM and BNP showed significant trends across NTBI quartiles. Multivariable regression analysis revealed that serum iron and low-density lipoprotein cholesterol were positively associated with NTBI but that age, d-ROM, and BNP showed an inverse association with this measure. In logistic regression analysis, NTBI was independently associated with a combination of higher levels of both d-ROM and BNP than the upper quartiles after adjustment for possible confounding factors.Serum NTBI concentration is detectable in the general population and shows significant inverse associations with oxidative stress and cardiac load. These findings indicate that serum NTBI in physiological conditions does not necessarily reflect increased oxidative stress, in contrast to the implications of higher levels in states of iron overload or pathological conditions.

Relationship of pulmonary function with myocardial microdamage and oxidative stress in the Japanese population without a history of cardiopulmonary disease

An association between pulmonary and cardiovascular impairment has been reported, but studies are lacking that focus on individuals without advanced impairment in the pulmonary or cardiovascular system. We aimed to investigate the relationship between myocardial microdamage and reduced pulmonary function in the Japanese population without a history of cardiopulmonary disease and to assess whether oxidative stress links the 2 features.We enrolled patients undergoing an annual health check-up and measured serum high-sensitivity cardiac troponin I (hs-cTnI) and derivatives of reactive oxygen metabolites (d-ROM) to evaluate myocardial microdamage and oxidative stress. To assess pulmonary function, we calculated forced vital capacity as a percentage of predicted value, forced expiratory volume in 1 second as a percentage of predicted value, and the ratio of forced expiratory volume in 1 second to forced vital capacity. Possible associations between each parameter of pulmonary function, hs-cTnI, and d-ROM were cross-sectionally investigated.The study included 1265 participants (57 ± 12 years). In multivariate regression analysis, the forced vital capacity as a percentage of predicted value was inversely associated with hs-cTnI levels after adjustment for possible confounders. In another multivariate model, all indices of pulmonary function were inversely correlated with d-ROM levels. We observed similar relationships in a multivariate regression model that included hs-cTnI and d-ROM simultaneously as independent variables. Levels of d-ROM and hs-cTnI also were significantly associated.These results highlight an inverse association of pulmonary function with hs-cTnI and d-ROM in the Japanese population without a history of cardiopulmonary disease. The findings suggest that in individuals without obvious cardiovascular and pulmonary diseases, reduced pulmonary function could reflect myocardial microdamage, at least in part through increased oxidative stress.

Close Association between Subclinical Atherosclerosis and Pulmonary Function in Middle-Aged Male Smokers

AIMS

Cigarette smoking provokes deleterious influences on cardiovascular and pulmonary systems, although the underlying relationship has not been sufficiently investigated especially in early-stage disease. The present study investigated possible associations between subclinical atherosclerosis and pulmonary function in middle-aged male smokers.

METHODS

Male smokers undergoing their periodic health check-up were enrolled in this study (n=3,775, 45±8 years). Pulmonary function was evaluated using spirometry by calculating forced vital capacity (FVC) as a percentage of predicted value (FVC%-predicted), forced expiratory volume in one second (FEV1) as a percentage of predicted value (FEV1%-predicted), and the ratio of FEV1 to FVC (FEV1/FVC). Subclinical atherosclerosis was assessed based on ankle-brachial pressure index (ABI), cardio-ankle vascular index (CAVI), ultrasound examination of the carotid intima-media thickness (IMT), and presence of plaque.

RESULTS

Multivariate regression analysis showed that ABI was positively associated with FVC%-predicted and FEV1%-predicted after adjustment for confounders including smoking intensity, while CAVI or carotid IMT was inversely associated with both. Participants with chronic obstructive pulmonary disease (COPD, n=256) showed reduced ABI and increased CAVI or carotid IMT compared with those without COPD, and participants with carotid plaque had lower pulmonary function than those without plaque. Reduced FEV1/FVC was an independent determinant of carotid plaque and decreased ABI was an independent determinant of COPD, as revealed by logistic regression analysis with the endpoint of carotid plaque presence or a diagnosis of COPD revealed.

CONCLUSIONS

Middle-aged male smokers showed a close association between subclinical atherosclerosis and pulmonary function, implying that smoking induced-vascular and pulmonary damage are interacting in early-stage disease.

Influence of smoking and smoking cessation on biomarkers of endothelial function and their association with mortality

BACKGROUND AND AIMS

Endothelial dysfunction precedes atherosclerosis and smoking is a well-known risk factor for the development of endothelial dysfunction. The aim of our study was to analyse the effect of smoking on circulating markers of endothelial function and to investigate whether such effects have an influence on the potential use of these markers to estimate cardiovascular risk.

METHODS

Stratified for smoking, levels of sE-/sP-/sL-selectin, von Willebrand (vWF), sICAM-1 and sVCAM-1, their association with mortality using Cox regression, and their accuracy of risk prediction using area-under-the-ROC-curve and net-reclassification-index were analysed in 1926 participants from the Ludwigshafen Risk and Cardiovascular Health (LURIC) - a prospective case-control study in patients who underwent coronary angiography with a median mortality follow-up of 10.6 years.

RESULTS

In smokers, higher concentrations of sICAM-1, sE-selectin sP-selectin, but lower concentrations of sL-selectin and sVCAM-1, were detected compared to never-smokers. A direct association with mortality was found for levels of sICAM-1, sVCAM-1 and vWF regardless of smoking. Low sL-selectin levels were inversely associated with mortality in heavy and light smokers, with hazard ratios of 0.72 and 0.67 per 1-SD increase, adjusted for cardiovascular risk factors. Adding sL-selectin to a model based on traditional risk factors significantly improved AUC from 0.725 to 0.752 (p = 0.034) with an NRI of 43% (16.9%-62.3%).

CONCLUSIONS

Smoking alters the concentration of circulating markers of endothelial function. sL-selectin is decreased in smokers, inversely associated with risk, and could be a useful marker to improve risk prediction.

Nicotine induces insulin resistance via downregulation of Nrf2 in cardiomyocyte

Clinical studies have demonstrated that cigarette smoking is strongly associated with insulin resistance and heart disease. Nicotine is considered the primary toxin constituent associated with smoking. However, the distinct molecular mechanism of nicotine-induced cardiac dysfunction remains unclear. Cardiomyocytes with nicotine-induced insulin resistance are characterized by decreased glucose uptake, as measured by 2-[N-(7-Nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-2-deoxy-d-glucose (2-NBDG), a fluorescent derivative of glucose, and reactive oxygen species (ROS) generation. Immunoblotting was used to evaluate the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), extracellular signal-related kinase (ERK) and phosphoinositide 3-kinase (PI3K, p85, Y607). We determined the impact of nicotine on insulin resistance and Nrf2, phospho-ERK and phospho-PI3K expression in the myocardial tissue of a mouse model. Nicotine increased ROS production and depressed insulin-induced glucose uptake in cardiomyocytes. Pretreatment with N-acetyl-L-cysteine (NAC), an antioxidant, reversed nicotine-inhibited glucose uptake induced by insulin. Nicotine exposure directly inhibited Nrf2 and increased ERK phosphorylation in cardiomyocytes, which were obstructed by NAC. Further exploration of signaling cascades revealed nicotine-induced ROS involved in inhibiting PI3K/Nrf2 and activating ERK in cardiomyocytes. Moreover, the mouse model treated with nicotine showed glucose intolerance and impaired insulin tolerance accompanied by inhibited PI3K/Nrf2 and increased ERK in myocardial tissues. Thus, nicotine induces insulin resistance via the downregulation of Nrf2 activity in cardiomyocytes, which is a potential mechanism of the pharmacological effects of nicotine. This study identified potential therapeutic targets against nicotine-related cardiovascular diseases.

Relationships of Obesity-Related Indices and Metabolic Syndrome with Subclinical Atherosclerosis in Middle-Aged Untreated Japanese Workers

Aim: Obesity is a social problem due to the prevalence of the Western lifestyle. In particular, visceral fat accumulation, which is a main component of metabolic syndrome, is closely associated with the progression of atherosclerosis. This study aimed to investigate the relationships of obesity-related indices and metabolic syndrome with subclinical atherosclerosis in middle-aged untreated workers.

Methods: Employees undergoing their periodic health check-up but without previous cardiovascular events or cardiovascular medications were enrolled in this study (n = 7,750). Body mass index (BMI), percent body fat, waist circumference, and visceral fat area were evaluated as obesity-related indices. Assessment of visceral fat area was performed by computed tomography (CT). Subclinical atherosclerosis was assessed by measuring arterial stiffness using cardio-ankle vascular index (CAVI) and by ultrasound examination of carotid intima-media thickness (IMT).

Results: Obesity-related indices were significantly correlated with each other and were positively associated with carotid IMT but negatively associated with CAVI in multivariate regression analysis. In a logistic regression analysis including CAVI and carotid IMT simultaneously, CAVI was negatively associated, but carotid IMT was positively associated, with obesity defined by each obesity-related index. In contrast, both CAVI and carotid IMT were positively associated with the presence of metabolic syndrome based on visceral fat accumulation.

Conclusions: Obesity-related indices were negatively associated with CAVI and positively associated with carotid IMT in middle-aged untreated workers, while both CAVI and carotid IMT were worsened in the presence of metabolic syndrome.

Vascular Response to Sildenafil Citrate in Aging and Age-Related Macular Degeneration

Age-related macular degeneration (AMD) - the leading cause of vision loss in the elderly - share many risks factors as atherosclerosis, which exhibits loss of vascular compliance resulting from aging and oxidative stress. Here, we attempt to explore choroidal and retinal vascular compliance in patients with AMD by evaluating dynamic vascular changes using live ocular imaging following treatment with oral sildenafil citrate, a phosphodiesterase type 5 (PDE5) inhibitor and potent vasodilator. Enhanced-depth imaging optical coherence tomography (EDI-OCT) and OCT angiography (OCT-A) were performed on 46 eyes of 23 subjects, including 15 patients with non-exudative AMD in one eye and exudative AMD in the fellow eye, and 8 age-matched control subjects. Choroidal thickness, choroidal vascularity, and retinal vessel density were measured across the central macula at 1 and 3 hours after a 100 mg oral dose of sildenafil citrate. Baseline choroidal thickness was 172.1 ± 60.0 μm in non-exudative AMD eyes, 196.4 ± 89.8 μm in exudative AMD eyes, and 207.4 ± 77.7 μm in control eyes, with no difference between the 3 groups (P = 0.116). After sildenafil, choroidal thickness increased by 6.0% to 9.0% at 1 and 3 hours in all groups (P = 0.001-0.014). Eyes from older subjects were associated with choroidal thinning at baseline (P = 0.005) and showed less choroidal expansion at 1 hour and 3 hours after sildenafil (P = 0.001) regardless of AMD status (P = 0.666). The choroidal thickening appeared to be primarily attributed to expansion of the stroma rather than luminal component. Retinal vascular density remained unchanged after sildenafil in all 3 groups (P = 0.281-0.587). Together, our studies suggest that vascular response of the choroid to sildenafil decreases with age, but is not affected by the presence of non-exudative or exudative AMD, providing insight into changes in vessel compliance in aging and AMD.

Smokeless tobacco extract inhibits proliferation and promotes apoptosis in oral mucous fibroblasts

The consumption of smokeless tobacco extract (STE) is growing rapidly, and it has been implicated in several human diseases including diabetes, inflammation and a number of types of cancer. The toxicity of STE requires evaluation, as it is known to induce numerous public health issues. To investigate whether STE serves a role in cultured human oral mucosa fibroblasts (hOMFs), the present study examined HOMF morphology with inverted microscopy and immunofluorescence staining. The cell viability was measured with MTT assays, which detected the cell apoptosis rate via flow cytometry. The activities of reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) were measured via flow cytometry and commercial kits, subsequent to exposing the cells to various concentrations of STE. Reverse transcription quantitative polymerase chain reaction and western blot analyses were used to demonstrate that the mRNA and the protein expression levels of cell cycle-associated genes (cyclin-dependent kinase inhibitor 1 and cyclin D1), apoptosis-associated genes [B cell lymphoma 2 (Bcl-2) and Bcl-2-associatied X protein], tumor protein (p53), nuclear factor kappa light chain enhancer of activated B cells (NF-κB)-transcription factor (p65) signaling pathways, NF-E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and NAD(P)H: quinoneoxidoreductase1 (NQO1). The results indicated that the hOMF cells were positive for cytokeratin staining. STE induced G1-S cell cycle progression and cell apoptosis by regulating the cell cycle or apoptosis-associated proteins. STE treatment increased the concentrations of ROS and MDA, and decreased the concentrations of SOD and CAT. STE unregulated phosphorylated-p53, NF-κB p65, Nrf2, HO-1, and NQO1 expression levels in the hOMF cells. The present study demonstrated that STE appears to promote oral disease.

The Influence of the Japanese Nationwide Cardiovascular Prevention System Health Guidance on Smoking Cessation Among Smokers: A Propensity Score Matching Analysis

Aim: We investigated whether 2 types of personalized health guidance (repeated and single counseling) in the Japanese nationwide cardiovascular prevention system promoted smoking cessation among smokers.

Methods: The study included 47,745 Japanese smokers aged 40 to 74 years classified into 2 personalized health guidance schemes. After a 1-year follow-up, we compared the rates of smoking cessation between individuals who had received counseling (“supported”) and those who had not received counseling (“unsupported”). Using propensity score matching analysis, we estimated the average treatment effect (ATE) of each approach on smoking cessation after balancing out the characteristics between the supported and unsupported groups. The propensity score regression model included age, medical insurance type, weight gain since the age of 20 years, exercise, eating habits, alcohol intake, quality of sleep, readiness to modify lifestyle, willingness to receive support, and body mass index.

Results: In the repeated counseling scheme, the age-adjusted rates of smoking cessation in the supported and unsupported groups were 8.8% and 6.3% for males, and 9.8% and 9.1% for females respectively. In the single counseling scheme, the corresponding rates were 8.4% and 7.3% for supported and unsupported males, and 11.0% and 11.7% for supported and unsupported females respectively. The ATE of repeated counseling was + 2.64% (95% confidence interval: + 1.51% to + 3.77%) for males and + 3.11% (−1.85% to +8.07%) for females. The ATE of single counseling was +0.61% (−1.17% to +2.38%) for males and −1.06% (−5.96% to +3.85%) for females.

Conclusions: In the Japanese cardiovascular prevention system, repeated counseling may promote smoking cessation among male smokers.

Associations of Tobacco Smoking with Impaired Endothelial Function: The Circulatory Risk in Communities Study (CIRCS)

Aims: Smoking impairs endothelial function as an acute effect. However, few population-based studies have examined the association between smoking status and endothelial function or the dose-response and duration- response association of smoking with endothelial function. We examined whether smoking habits were associated with impaired endothelial function depending on smoking dose and duration.

Methods: We conducted a cross-sectional study of 910 men and women aged 30–79 years from 2013 to 2016. Statistical analyses of the data were conducted between 2016 and 2017. Endothelial function was assessed by brachial artery flow-mediated dilation (FMD) measurement. Low FMD was defined in two ways as the cutoff point based on the lowest quartile of %FMD (< 5.1%) and median of %FMD (< 6.8%), regarding as impaired endothelial function. We investigated the smoking status in terms of cigarettes consumed per day and the duration of smoking.

Results: Heavy and chronic smokers were associated with a high prevalence of impaired endothelial function. Those associations did not change substantially after adjustment for other cardiovascular risk factors. Among all participants, the multivariable-adjusted ORs (95% CIs) of low FMD (< 5.1%) with reference to never smokers were 2.23 (1.00–5.14) for current heavy smokers of ≥ 30 cigarettes per day, 1.83 (1.04–3.20) for heavy smokers of ≥ 40 pack-years, and 2.16 (1.15–4.06) for chronic smokers of ≥ 40 years. For low FMD (< 6.8%) those values was 2.17 (1.01–5.05), 1.70 (1.01–2.86), and 1.98 (1.07–3.69), respectively.

Conclusions: Similar associations were observed among only men. Heavy or long-term tobacco smoking may induce impaired endothelial function.

Monocyte-derived exosomes upon exposure to cigarette smoke condensate alter their characteristics and show protective effect against cytotoxicity and HIV-1 replication

Smoking is known to exacerbate HIV-1 pathogenesis, especially in monocytes, through the oxidative stress pathway. Exosomes are known to alter HIV-1 pathogenesis through inter-cellular communication. However, the role of exosomes in smoking-mediated HIV-1 pathogenesis is unknown. In this study, we investigated the effect of cigarette smoke condensate (CSC) on the characteristics of monocyte-derived exosomes and their influence on HIV-1 replication. Initially, we demonstrated that CSC reduced total protein and antioxidant capacity in exosomes derived from HIV-1-infected and uninfected macrophages. The exosomes from CSC-treated uninfected cells showed a protective effect against cytotoxicity and viral replication in HIV-1-infected macrophages. However, exosomes derived from HIV-1-infected cells lost their protective capacity. The results suggest that the exosomal defense is likely to be more effective during the early phase of HIV-1 infection and diminishes at the latter phase. Furthermore, we showed CSC-mediated upregulation of catalase in exosomes from uninfected cells, with a decrease in the levels of catalase and PRDX6 in exosomes derived from HIV-1-infected cells. These results suggest a potential role of antioxidant enzymes, which are differentially packaged into CSC-exposed HIV-1-infected and uninfected cell-derived exosomes, on HIV-1 replication of recipient cells. Overall, our study suggests a novel role of exosomes in tobacco-mediated HIV-1 pathogenesis.