The impact of rapid atrial pacing on ADMA and endothelial NOS

Background

The endothelial nitric oxide synthase (eNOS) inhibitor asymmetric dimethylarginine (ADMA) is a well-established risk factor for oxidative stress, vascular dysfunction, and congestive heart failure. The aim of the present study was to determine the impact of rapid atrial pacing (RAP) on ADMA levels and eNOS expression.

Methods and results

ADMA levels were studied in 60 age- and gender-matched patients. Thirty five patients had persistent atrial fibrillation (AF) ≥ 4 months. In AF-patients, parameters were studied before and 24 h after electrical cardioversion. Moreover, ADMA, eNOS expression, and calcium-handling proteins were studied in pigs subjected to RAP as well as in endothelial cell (EC) cultures. ADMA level was significantly higher in AF compared to sinus rhythm patients (p = 0.024). ADMA was highest in AF-patients, who also showed elevated troponin T (TnT) levels. Moreover, ADMA showed a significant linear correlation to TnT (r = 0.47; p < 0.01). After electrical cardioversion ADMA returned to normal within 24 h. In pigs, RAP for 7 h increased ADMA levels (p = 0.018) and TnI (p < 0.05), and reduced mRNA expression of ventricular and aortic eNOS (− 80%; p < 0.05) compared to sham-control. However, ADMA per se did not affect eNOS mRNA level in EC cultures.

Conclusion

The current study shows that acute and persistent episodes of atrial tachyarrhythmia are associated with elevated ADMA levels accompanied by increased ischemic myocardial markers. Moreover, RAP increases ADMA and down-regulates eNOS expression in an ADMA-independent manner. We conclude that the combination of these two separate and potentially synergistic mechanisms may contribute to long-term vascular injury during atrial tachyarrhythmia.     

Life satisfaction and cardiovascular disease risk in Poland

Introduction

Cardiovascular disease is the most common cause of death. Life satisfaction is a predictor of morbidity and mortality, irrespectively of objective measures of health status. The aim of the study was to evaluate the relationship between life satisfaction (LS) and cardiovascular disease risk (CVD) assessed with the Framingham Risk Score (FRS) in Polish adults.

Material and methods

Past, present and projected LS were estimated. The FRS reflecting 10-year CVD risk was calculated from health indices and lifestyle parameters. Relationships between LS and FRS were tested by two-way analysis of variance in 489 men and 591 women, 40–50 years of age.

Results

Subjects with a reduction in LS over time had a higher FRS compared to peers with an improvement in LS. The relationship between current LS and FRS had a J-shape in men; FRS was lowest in men with an LS of 5–7 (average LS), slightly higher in men with an LS of 8–10 (highest LS), and highest in men with an LS of 1–4 (lowest LS). Among women, there was an inverse linear relationship between LS and FRS: the higher the LS, the lower FRS. There was a strong linear relationship between predicted LS and CVD risk. Highest risk was evident in subjects with low LS in whom low LS was predicted over the next five years.

Conclusions

Low LS (dissatisfaction) thus has a long-term negative effect on CVD risk in Polish adults of both sexes.     

Effect of the transdermal low-level laser therapy on endothelial function

The effect of low-level laser therapy (LLLT) on the cardiovascular system is not fully established. Since the endothelium is an important endocrine element, establishing the mechanisms of LLLT action is an important issue.The aim of the study was to evaluate the effect of transdermal LLLT on endothelial function.In this study, healthy volunteers (n?=?40, age?=?20–40 years) were enrolled. N?=?30 (14 female, 16 male, mean age 30?±?5 years) constituted the laser-irradiated group (LG). The remaining 10 subjects (6 women, 4 men, mean age 28?±?5 years) constituted the control group (CG). Participants were subjected to LLLT once a day for three consecutive days. Blood for biochemical assessments was drawn before the first irradiation and 24 h after the last session. In the LG, transdermal illumination of radial artery was conducted (a semiconductor laser λ?=?808 nm, irradiation 50 mW, energy density 1.6 W/cm² and a dose 20 J/day, a total dose of 60 J). Biochemical parameters (reflecting angiogenesis: vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), angiostatin; antioxidative status: glutathione (GSH) and the nitric oxide metabolic pathway: symmetric dimethylarginine (SDMA), asymmetric dimethylarginine (ADMA) and l-arginine) were assessed. In the LG, a significant increase in GSH levels and considerable decrease in angiostatin concentration following the LLLT were observed. No significant differences in levels of the VEGF, FGF, SDMA, ADMA were observed.LLLT modifies vascular endothelial function by increasing its antioxidant and angiogenic potential. We found no significant differences in levels of the nitric oxide pathway metabolites within 24 h following the LLLT irradiation.     

Mediterranean Diet and Hip Fracture in Swedish Men and Women

A Mediterranean diet, known to have beneficial effects on cardiovascular health, may also influence the risk of hip fracture although previous studies present discrepant results. We therefore aimed to determine whether the rate of hip fracture was associated with degree of adherence to a Mediterranean diet. We combined two Swedish cohort studies consisting of 37,903 men and 33,403 women (total n = 71,333, mean age 60 years) free of previous cardiovascular disease and cancer who answered a medical and a food‐frequency questionnaire in 1997. A modified Mediterranean diet score (mMED; range, 0 to 8 points) was created based on high consumption of fruits and vegetables, legumes and nuts, whole grains, fermented dairy products, fish, and olive/rapeseed oil, moderate intake of alcohol, and low intake of red and processed meat. Incident hip fractures between January 1, 1998, and December 31, 2012, were retrieved from the National Patient Register. Hazard ratios (HRs) and 95% confidence intervals (CIs) adjusted for potential confounders were calculated using Cox proportional hazards regression. Differences in age at hip fracture were calculated using multivariable Laplace regression. During follow‐up, 3175 hip fractures occurred at a median age of 73.3 years. One unit increase in the mMED was associated with 6% lower hip fracture rate (adjusted HR = 0.94; 95% CI, 0.92 to 0.96) and with a 3‐month higher median age at hip fracture (50th percentile difference = 2.8 months; 95% CI, 1.4 to 4.2). Comparing the highest quintile of adherence to the mMED (6 to 8 points) with the lowest (0 to 2 points) conferred an adjusted HR of hip fracture of 0.78 (95% CI, 0.69 to 0.89) and a 12‐month higher median age of hip fracture (50th percentile difference = 11.6 months; 95% CI, 4.2 to 19.0). Results were similar in men and women. We conclude that higher adherence to a Mediterranean‐like diet is associated with lower risk of future hip fracture. © 2016 American Society for Bone and Mineral Research.     

Platelet Activation During Allergic Inflammation

Blood platelets, apart from their traditional and well-recognised function in haemostasis, play an essential and active role in allergic inflammation e.g. through their participation in cell recruitment from blood to site of immune reactivity as a result of direct interactions with leukocytes, and through the release of inflammatory mediators. Platelet activation may occur during human allergic reactions both systemically and locally at the site of allergic inflammation as a result of an IgE-dependent process and as a secondary event caused by other inflammatory or immune stimuli. Altered platelet function as measured by platelet secretion, expression of surface molecules, aggregation, adhesion or arachidonic acid metabolism has been found in patients suffering from allergic diseases. These blood elements have been implicated in the pathogenesis of allergic diseases associated with the so-called atopic diathesis. This paper reviews the platelet activity and reactivity in allergic inflammation, along with our own findings concerning platelet release reaction and the phenomenon of platelet aggregation in patients with different clinical forms of allergy.     

The spread of medical fake news in social media – The pilot quantitative study

Objectives

Fake news: misinformation and falsehood of health news in social media constitute a potential threat to the public health, but the scope of this issue remains unclear. Our pilot study is an initial attempt to measure a number of the top shared health misinformation stories in the Polish language social media.

Fruit and vegetable consumption and risk of cholecystectomy: a prospective cohort study of women and men

Purpose

Epidemiologic data on whether consumption of fruit and vegetables (FVs) decreases the risk of gallstone disease are sparse. Therefore, we examined the association between FV consumption and the 14-year risk of symptomatic gallstone disease (defined as occurrence of cholecystectomy) in a large group of middle-aged and elderly persons.

Methods

Data from two population-based cohorts were used, which included 74,554 men and women (born 1914–1952). Participants filled in a food frequency questionnaire in the late fall of 1997 and were followed up for cholecystectomy between 1998 and 2011 via linkage to the Swedish Patient Register. Cox regression models were used to obtain hazard ratios (HRs).

Results

During 939,715 person-years of follow-up, 2120 participants underwent a cholecystectomy (1120 women and 1000 men). An inverse association between FV consumption and risk of cholecystectomy was observed in age- and sex-adjusted analyses (P _trend = .036) but not in confounder-adjusted analyses (P _trend = .43). The multivariable-adjusted HR was 0.95 (95 % CI 0.83–1.08) for the highest compared with the lowest sex-specific quartile of FV consumption. There was no evidence of interactions with age (P = .25) or sex (P = .72) in analyses pooled by sex. However, an age-by-FV consumption interaction was observed in separate analyses of women (P = .010), with decreased HRs of cholecystectomy for ages up to 60 years.

Conclusions

This study supports an inverse association between FV consumption and risk cholecystectomy in women, although the association was restricted to women aged 48–60 years. In contrast, the study does not support an association in men.