The evaluation of inflammatory and oxidative stress biomarkers on coffee-diabetes association: results from the 10-year follow-up of the ATTICA Study (2002-2012).

BACKGROUND/OBJECTIVES: The purpose of this work was to investigate the association between coffee drinking and diabetes development and potential mediation by oxidative stress and inflammatory biomarkers. SUBJECTS/METHODS: In 2001-2002, a random sample of 1514 men (18-87 years old) and 1528 women (18-89 years old) were selected to participate in the ATTICA study (Athens metropolitan area, Greece). A validated food-frequency questionnaire was used to assess coffee drinking (abstention, casual, habitual) and other lifestyle and dietary factors. Evaluation of oxidative stress and inflammatory markers was also performed. During 2011-2012, the 10-year follow-up of the ATTICA study was carried out. The outcome of interest in this work was incidence of type 2 diabetes, defined according to American Diabetes Association criteria. RESULTS: During follow-up, 191 incident cases of diabetes were documented (incidence 13.4% in men and 12.4% in women). After various adjustments, individuals who consumed ⩾250 ml of coffee (≈1.5cup) had 54% lower odds of developing diabetes (95% confidence interval: 0.24, 0.90), as compared with abstainers. A dose-response linear trend between coffee drinking and diabetes incidence was also observed (P for trend=0.017). When controlling for several oxidative stress and inflammatory biomarkers, the inverse association between habitual coffee drinking and diabetes was found to be mediated by serum amyloid-A levels. CONCLUSIONS: This work highlights the significance of long-term habitual coffee drinking against diabetes onset. The anti-inflammatory effect of several coffee components may be responsible for this protection.

Gender-specific distribution of selenium to serum selenoproteins: associations with total selenium levels, age, smoking, body mass index, and physical activity.

The epidemiology of selenium (Se) is mainly based on the determination of total serum selenium levels (TSe) which by many aspects is an inadequate marker of Se status. In this study we applied a recently developed LC-ICP-MS method, for the determination of the selenium content of the three main serum selenium-containing proteins, in a subcohort of the ATTICA study. This enables us to investigate whether the selenium distribution to selenoproteins may correlate with demographic (age, gender) and lifestyle variables (smoking, physical activity) that are crucial for the development of chronic diseases. A sub-sample from the ATTICA Study, consisted of 236 males (40 ± 11 years) and 163 females (38 ± 12 years), was selected. The selenium content of glutathione peroxidase (GPx-3), selenoprotein P (SelP) and selenoalbumin (SeAlb) was determined in serum by LC-ICP/MS method. We found that 26% of TSe is found in GPx-3, 61% in SelP and 13% in SeAlb. We have assessed the different ratios of selenoproteins' selenium content (Se-GPX-3/Se-SelP, Se-GPX-3/Se-SeAlb, Se-SelP/Se-SeAlb), showing that people with similar TSe may have different distribution of this selenium to selenoproteins. Total selenium levels and gender are the variables that mostly affect selenium distribution to selenoproteins while age, smoking, physical activity and BMI do not significantly influence selenium distribution. In conclusion, the simultaneous determination of the selenium content of serum selenium-containing selenoproteins is necessary for a thorough estimation of selenium status. The ratio of the Se content between selenoproteins may be proven a novel, valid marker of selenium status.

Divergent anti-inflammatory effects of different oil acute consumption on healthy individuals.

BACKGROUND/OBJECTIVES: Inter-cellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and tumor necrosis factor-α (TNF-α), are implicated in atherogenesis. In addition, several types of oil as part of different types of diet are associated with the initiation of atherosclerosis and consequently with the risk of cardiovascular disease. However, the exact role of oil consumption on vascular inflammation remains unknown. In this parallel study, we assessed the acute effects of extra virgin olive oil, soy oil, corn oil and cod liver oil on circulating soluble(s) forms of adhesion molecules and TNF-α. SUBJECTS/METHODS: In all, 67 healthy volunteers were randomized to receive 50 ml of oil. Soluble forms of VCAM-1, ICAM-1 and TNF-α were measured by enzyme-linked immunosorbent assay at baseline and at 3 h post oil consumption. RESULTS: All types of oil had no significant effect on soluble VCAM-1 levels (P=nonsignificant (NS) for all). On the contrary, all oil types decreased ICAM-1 levels (P<0.01). Olive oil (P<0.05), soy oil and cod liver oil (P<0.01 for both) reduced TNF-α levels significantly, in contrast to corn oil, which induced a nonsignificant decrease (P=NS). Moreover, there was a significant correlation between the absolute change in ICAM-1 and TNF-α levels (ρ=0.379, P<0.05), but not between the absolute changes in VCAM-1 and TNF-α levels (ρ=0.019, P=NS). CONCLUSIONS: Acute consumption of all types of oil decreased significantly ICAM-1 levels. In addition, olive oil, soy oil and cod liver oil decreased significantly TNF-α levels. Moreover, the absolute change in TNF-α levels was correlated with the absolute change in ICAM-1 levels. These findings indicate that acute consumption of specific types of oil is associated with specific significant anti-inflammatory effects.

Dietary habits of Greek adults and serum total selenium concentration: the ATTICA study.

PURPOSE: The trace element selenium is an essential micronutrient for human health, and its low levels in serum are implicated in the pathogenesis of several chronic diseases. The determination of total serum selenium levels may contribute to the assessment of the health status of all populations. Since the serum selenium levels are highly affected by diet, we assessed its association with the dietary habits of Greek adults. METHODS: Serum selenium levels were determined with inductively coupled plasma mass spectrometry in a cohort of 506 participants (men: 296, women: 210) aged 18-75 from the ATTICA study. Food consumption was evaluated with a validated food-frequency questionnaire. RESULTS: Evaluation of the relationship between serum total selenium with major food groups and beverages by multi-adjusted analysis revealed that serum selenium was positively correlated with the consumption of red meat (2.37 ± 0.91, p = 0.01) while the consumption of other selenium-containing foods (i.e., fish, cereals, dairy products, vegetables) did not demonstrate such a relationship. Moreover, principal component analysis revealed that the adoption of a vegetarian type of diet is inversely correlated with total selenium (-3.94 ± 2.28, p = 0.08). CONCLUSIONS: Among the dietary habits that were examined, red meat seems to be the major determinant of serum selenium in Greek adults.

Effect of chronic coffee consumption on aortic stiffness and wave reflections in hypertensive patients.

OBJECTIVE: Aortic stiffness and wave reflections are important markers and prognosticators of cardiovascular risk. Caffeine increases acutely aortic stiffness and wave reflections. Furthermore, chronic coffee consumption is associated with increased aortic stiffness and wave reflections in normotensive subjects. In the present study, we aimed to assess the association between chronic coffee consumption, and aortic stiffness and wave reflections in hypertensive patients. DESIGN: Epidemiological survey. SETTING: Hypertension Unit, University Hospital. SUBJECTS-METHODS: We examined 259 never-treated hypertensives (age 50+/-12 years, 165 males) without diabetes mellitus, who were asked to describe in detail the type and amount of coffee they consumed. Carotid-femoral pulse wave velocity (PWV) and augmentation index (AIx) were measured non-invasively as indices of aortic stiffness and wave reflections, respectively. RESULTS: When controlled for gender, age, height, smoking status, heart rate, mean pressure, HDL cholesterol and hsCRP, AIx was found to be higher with increasing daily coffee consumption. Post hoc analysis revealed that all groups of coffee consumption had higher AIx compared to no-consumption. PWV did not differ among groups of daily coffee consumption. Each participant had 35% higher relative risk of having high AIx for each cup (150 ml) of coffee per day, and 40% higher relative risk for each 10 cup-years. CONCLUSIONS: Coffee consumption is associated with increased wave reflections, but not aortic stiffness in never-treated hypertensive patients. This finding may have important clinical implications for cardiovascular health in hypertensive subjects.

Distensibility of the ascending aorta in coronary artery disease and changes after nifedipine administration.

To study the effect of nifedipine on aortic distensibility in patients with coronary artery disease, ascending aorta distensibility was measured before and 10 min after 10 mg of nifedipine was given sublingually in 13 patients with coronary artery disease and 12 control subjects. Aortic distensibility was calculated as a function of changes in the aortic diameter and pulse pressure. Aortic diameters were measured by echocardiography and aortic pressures were measured directly by catheterization of the ascending aorta. At baseline, aortic distensibility was lower in patients with coronary artery disease compared with control (0.922 +/- 0.367 vs 2.456 +/- 0.588 10(-6).cm2.dyn-1, respectively, p < 0.001). After nifedipine administration, aortic distensibility increased significantly both in normal subjects (by 0.812 +/- 0.316 10(-6).cm2.dyn-1-36.5 +/- 19 percent; p < 0.001) and in patients with coronary artery disease (by 0.296 +/- 0.203 10(-6).cm2.dyn-1-36.6 +/- 28.2 percent; p < 0.001). These results indicate that nifedipine administration increases aortic distensibility in both normal subjects and patients with coronary artery disease.

Ascending aorta distensibility abnormalities in hypertensive patients and response to nifedipine administration.

PURPOSE: The purpose of the present investigation was to study the distensibility of the ascending aorta in patients with arterial hypertension and normal subjects before and after administration of a calcium antagonist, nifedipine. PATIENTS AND METHODS: The distensibility of the ascending aorta was measured before and after nifedipine administration in 22 male hypertensive patients and 12 age-matched male normotensive subjects. Aortic distensibility was calculated as a function of changes in aortic diameter and pulse pressure, using the formula: 2 x (pulsatile change in aortic diameter)/[(diastolic aortic diameter) x (aortic pulse pressure)]. Aortic diameters were measured by echocardiography and aortic pressures were obtained by catheterization of the ascending aorta. RESULTS: In the basal state, the distensibility of the ascending aorta and aortic strain were lower in hypertensive patients than in normotensive subjects (p < 0.001); the lower aortic distensibility, however, was associated with a greater distending pressure. A good inverse correlation (r = -0.81) was found between mean aortic pressure and aortic distensibility. The aortic distensibility was increased after nifedipine administration in both groups; this increase in aortic distensibility, however, was lower in the patients with hypertension compared with normotensive subjects (p < 0.001). CONCLUSIONS: Aortic distensibility is decreased in patients with arterial hypertension. Nifedipine administration increased the distensibility of the ascending aorta both in patients with arterial hypertension and in normotensive subjects. The increase of aortic distensibility after nifedipine administration was lower in hypertensive patients.