Association between increased plasma ceramides and chronic kidney disease in patients with and without ischemic heart disease.

AIM: Plasma levels of certain ceramides are increased in patients with ischemic heart disease (IHD). Many risk factors for IHD are also risk factors for chronic kidney disease (CKD), but it is currently uncertain whether plasma ceramide levels are increased in patients with CKD. METHODS: We measured six previously identified high-risk plasma ceramide concentrations [Cer(d18:1/16:0), Cer(d18:1/18:0), Cer(d18:1/20:0), Cer(d18:1/22:0), Cer(d18:1/24:0) and Cer(d18:1/24:1)] in 415 middle-aged individuals who attended our clinical Cardiology and Diabetes services over a period of 9 months. RESULTS: A total of 97 patients had CKD (defined as e-GFRCKD-EPI<60ml/min/1.73m2 and/or urinary albumin-to-creatinine ratio≥30mg/g), 117 had established IHD and 242 had type 2 diabetes. Patients with CKD had significantly (P=0.005 or less) higher levels of plasma Cer(d18:1/16:0), Cer(d18:1/18:0), Cer(d18:1/20:0), Cer(d18:1/22:0), Cer(d18:1/24:0), and Cer(d18:1/24:1) compared to those without CKD. The presence of CKD remained significantly associated with higher levels of plasma ceramides (standardized beta coefficients ranging from 0.124 to 0.227, P<0.001) even after adjustment for body mass index, smoking, hypertension, diabetes, prior IHD, plasma LDL-cholesterol, hs-C-reactive protein levels and use of any lipid-lowering medications. Notably, more advanced stages of CKD and abnormal albuminuria were both associated (independently of each other) with increased levels of plasma ceramides. These results were consistent in all subgroups considered, including patients with and without established IHD or those with and without diabetes. CONCLUSION: Increased levels of plasma ceramides are associated with CKD independently of pre-existing IHD, diabetes and other established cardiovascular risk factors.

Association between specific plasma ceramides and high-sensitivity C-reactive protein levels in postmenopausal women with type 2 diabetes.

AIM: Emerging evidence suggests that specific plasma ceramides are involved in the pathophysiology of cardiovascular disease (CVD) and other inflammation-associated diseases. However, scarce information is currently available on the association between distinct plasma ceramides (that have been associated with increased cardiovascular morbidity and mortality) and plasma high-sensitivity C-reactive protein (hs-CRP) concentrations in patients with type 2 diabetes mellitus (T2DM), a group of individuals at high risk of developing CVD and other chronic inflammation-related conditions. METHODS: We measured six previously identified high-risk plasma ceramide species [Cer(d18:1/16:0), Cer(d18:1/18:0), Cer(d18:1/20:0), Cer(d18:1/22:0), Cer(d18:1/24:0), Cer(d18:1/24:1)] in 92 postmenopausal women with T2DM attending the diabetes outpatient service over a 3-month period. Plasma ceramide levels were measured using targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay. RESULTS: Plasma hs-CRP levels were positively associated with all measured ceramides in univariable linear regression analyses. However, only plasma Cer(d18:1/16:0) (standard ß coefficient: 0.27, P=0.015), Cer(d18:1/22:0) (standard ß coefficient: 0.25, P=0.032) and Cer(d18:1/24:1) (standard ß coefficient: 0.30, P=0.007) remained significantly associated with increased plasma hs-CRP levels after adjusting for age, adiposity measures, diabetes duration, HbA1c, insulin resistance, smoking, hypertension, plasma LDL cholesterol, estimated glomerular filtration rate, preexisting ischaemic heart disease and use of lipid-lowering, antihypertensive, antiplatelet or hypoglycaemic drugs. CONCLUSION: In postmenopausal women with T2DM, elevated levels of specific plasma ceramides are associated with higher plasma hs-CRP levels independent of established cardiovascular risk factors, diabetes-related variables and other potential confounding factors.

Associations between specific plasma ceramides and severity of coronary-artery stenosis assessed by coronary angiography.

AIM: Recent prospective studies have identified distinct plasma ceramides as strong predictors of major adverse cardiovascular events in patients with established or suspected coronary artery disease (CAD). Currently, it is uncertain whether higher levels of distinct plasma ceramides are associated with greater angiographic severity of coronary-artery stenoses in this patient population. METHODS: We measured six previously identified high-risk plasma ceramide species [Cer(d18:1/16:0), Cer(d18:1/18:0), Cer(d18:1/20:0), Cer(d18:1/22:0), Cer(d18:1/24:0) and Cer(d18:1/24:1)] in 167 consecutive patients with established or suspected CAD, who underwent urgent or elective coronary angiography. RESULTS: Approximately 77% of patients had a significant stenosis (≥50%) in one or more of the main coronary arteries, the majority of whom (∼60%) had a significant stenosis in the left anterior descending (LAD) artery. Of the six measured plasma ceramides, higher levels of plasma Cer(d18:1/20:0) (adjusted-odds ratio 1.39, 95%CI 1.0-1.99), Cer(d18:1/22:0) (adjusted-odds ratio 1.57, 95%CI 1.08-2.29) and Cer(d18:1/24:0) (adjusted-odds ratio 1.59, 95%CI 1.08-2.32) were significantly associated with the presence of LAD stenosis≥50%, after adjustment for age, sex, smoking, pre-existing CAD, hypertension, diabetes, dyslipidaemia, lipid-lowering therapy, estimated glomerular filtration rate and plasma C-reactive protein levels. Almost identical results were found even after excluding patients (n=15) with acute ST-elevation myocardial infarction. Similar results were also found when patients were categorized according to the Gensini severity score. CONCLUSION: Our cross-sectional study shows for the first time that higher levels of specific plasma ceramides are independently associated with a greater severity of coronary-artery stenoses in the LAD artery in patients who had suspected or established CAD.

Association between decreasing estimated glomerular filtration rate and risk of cardiac conduction defects in patients with type 2 diabetes.

AIM: We aimed to assess the association between decreasing estimated glomerular filtration rate (eGFR) or abnormal albuminuria and the risk of certain cardiac conduction defects in patients with type 2 diabetes mellitus (T2DM). METHODS: We examined a hospital-based sample of 923 patients with T2DM discharged from our Division of Endocrinology over the years 2007-2014. Standard electrocardiograms (ECGs) were performed in all patients. eGFR was estimated by using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation, whilst albuminuria was measured by an immuno-nephelometric method on morning spot urine samples. RESULTS: A total of 253 (27.4%) patients had some type of cardiac conduction defects on standard ECGs (defined as at least one heart block among first-degree atrioventricular block, second-degree block, third-degree block, left bundle branch block, right bundle branch block, left anterior hemi-block or left posterior hemi-block). Prevalence of patients with eGFRCKD-EPI < 30 mL/min/1.73 m2, eGFRCKD-EPI 59-30 mL/min/1.73 m2 or abnormal albuminuria (i.e. urinary albumin-to-creatinine ratio ≥ 30 mg/g) were 7.0%, 29.4% and 41.3%, respectively. After adjustment for known cardiovascular risk factors, diabetes-related variables and potential confounders, there was a significant, graded association between decreasing eGFR values and risk of any cardiac conduction defects [adjusted-odds ratios of 2.05 (95% CI: 1.2-3.5), 2.85 (95% CI: 1.6-5.1) and 3.62 (95% CI: 1.6-8.1) for eGFRCKD-EPI 89-60, eGFRCKD-EPI 59-30 and eGFRCKD-EPI < 30 mL/min/1.73 m2, respectively]. Conversely, abnormal albuminuria was not independently associated with an increased risk of any conduction defects (adjusted-odds ratio: 1.09, 95% CI: 0.7-1.6). CONCLUSION: Decreasing eGFR is independently associated with an increased risk of cardiac conduction defects in hospitalized patients with T2DM.

Hyperuricemia is associated with an increased prevalence of paroxysmal atrial fibrillation in patients with type 2 diabetes referred for clinically indicated 24-h Holter monitoring.

PURPOSE: Several studies have reported an association between hyperuricemia and increased risk of permanent atrial fibrillation (AF) in patients with and without type 2 diabetes mellitus (T2DM). Currently, no published data are available on the relationship between hyperuricemia and risk of paroxysmal AF. METHODS: We retrospectively evaluated 245 T2DM outpatients without pre-existing AF, cancer, cirrhosis and end-stage renal disease, who underwent a 24-h ECG-Holter monitoring for various clinical indications. Hyperuricemia was defined as a serum uric acid level >7 mg/dl for men and >6 mg/dl for women or allopurinol use. The diagnosis of paroxysmal AF was confirmed in affected individuals on the basis of 24-h ECG-Holter monitoring by experienced cardiologists. RESULTS: Hyperuricemia was observed in 59 (24.1%) patients, whereas paroxysmal AF was found in 11 (4.5%) patients. The prevalence of paroxysmal AF was higher in patients with hyperuricemia than in those without hyperuricemia (10.2 vs. 2.7%, p = 0.026). Logistic regression analysis showed that hyperuricemia was associated with an increased risk of prevalent paroxysmal AF. This association remained significant even after adjustment for age, metabolic syndrome and chronic kidney disease (adjusted-odds ratio 4.01, 95% CI 1.08-14.9; p = 0.039). Similar results were found when we used serum uric acid levels as a continuous measure. CONCLUSIONS: This study shows for the first time that hyperuricemia is independently associated with an approximately fourfold increased risk of prevalent paroxysmal AF in patients with T2DM. These findings may partly explain the increased risk of permanent atrial fibrillation and cardiovascular death observed among patients with hyperuricemia.

Evidence of left atrial remodeling and left ventricular diastolic dysfunction in type 2 diabetes mellitus with preserved systolic function.

BACKGROUND AND AIMS: Prognosis of type 2 diabetes is associated with the occurrence of cardiovascular diseases. Left atrial (LA) size is a predictor of outcome in several diseases, including diabetes. Long duration of diabetes is an established risk factor of poor prognosis. No data are available on the relationship between LA size and duration of diabetes. The present study was aimed to investigate the relationship between LA volume index (LAVI) and the duration of diabetes to test the hypothesis that LA volume will increase as a function of diabetes duration. METHODS AND RESULTS: Forty-four male patients with newly diagnosed and 172 male patients with established type 2 diabetes were recruited for this cross-sectional study. All patients were evaluated with a transthoracic echocardiographic Doppler. About 28.2% of patients had increased LAVI. Indices of both diastolic and systolic function were significantly lower in patients with larger left atrium. The values of LAVI increased across classes of duration of diabetes. In multivariable analysis, longer duration was a predictor of LAVI ≥34 ml/m2 (odds ratio 1.65, 95% CI 1.11-2.46, p = 0.014) after adjusting for age, hemoglobin A1c, hypertension, microvascular complication status, and relevant echocardiographic parameters of systolic and diastolic function. CONCLUSIONS: These results indicate that duration of diabetes is strongly and positively associated with larger LAVI in type 2 diabetic men with preserved systolic function. Future studies are needed to better elucidate the biological mechanisms underlying linking type 2 diabetes with abnormally increased LAVI in subjects with type 2 diabetes.

Additional value of pulmonary vein parameters in defining pseudonormalization of mitral inflow pattern.

BACKGROUND: An echocardiographic assessment of left ventricular (LV) diastolic dysfunction is still challenging when identifying a pseudonormal mitral pattern (PSE) in an unselected population. The present study analyzed and compared the accuracy of various parameters in correctly identifying a PSE pattern in patients with a broad range of ejection fraction (EF) and degree of mitral regurgitation. METHODS: Eighty-two patients with E/A > or = 1 and an invasive determination of left ventricular end-diastolic pressure (LVEDP) were enrolled in the study. Mitral E wave (E(max)) and A (A(max)) velocities, E (DTe) and A (DTa) deceleration times, pulmonary vein systolic and diastolic velocities, and time velocity integrals were measured. The different duration between mitral and pulmonary vein A wave (A'-A) also was calculated. E(max) and E/A during Valsalva maneuver were measured and expressed as percentage compared with baseline. LV end-diastolic (LVD), end-systolic (LVS), and EF were measured from the apical four-chambers view (area-length method). Left atrial end-systolic (LA(max)) and end-diastolic (LA(min)) were measured from the apical four- and two-chambers views (area-length method). Left atrial filling volume (LA(fill)) was the difference between LA(max) and LA(min). Mitral regurgitant volume was estimated by the following equation: MR(vol) = 6.18 + (1.01 * LA(fill)) - (0.783 * PVs %). RESULTS: Thirty-two patients (age: 55 +/- 21 years; 75% male) had LVEDP < or = 18 mmHg and were classified as normal mitral pattern (Group 1). Fifty patients (age: 57 +/- 22 years; 76% male) had LVEDP > 18 mmHg, and were classified accordingly as having PSE (Group 2). At logistic univariate analysis, DTa (0.005), LV EF (0.01), A'-A (< 0.0001) and % E/A (0.03) were the more powerful predictors of PSE. A'-A had the highest global accuracy in identifying PSE in patients with reduced (90%) and normal (88%) LV EF. CONCLUSION: A'-A has the highest accuracy in identifying PSE in an unselected population. This parameters should be implemented in routine echocardiography since it allows additional information about LV diastolic function assessment.

Tailoring anti-hypertensive treatment in the elderly.

The treatment of hypertension in the elderly has to take into account co-existing pathology. However, the benefit from treatment are large in terms owing to the frequency of cardiovascular events in the elderly. The benefits observed in randomised controlled trials are reviewed together with the adverse effects of the individual treatments. The optimal use of anti-hypertensive treatment is considered in light of any concomitant disease; for example beta-blockers or calcium channel blockers when angina is present and the avoidance of diuretics in the presence of gout. Important hazardous drug interactions are also discussed. It is concluded that diuretics are still the first choice in uncomplicated hypertension and the least expensive. However the place of anti-hypertensive treatment is not established in those over the age of 80 years.

Association between abdominal aortic diameter and peripheral vascular disease.

Fifty-four elderly people 81.2 years +/- 7.4 (mean age +/- s.d., range 66-98 years) were selected. These included 20 men (78.6 +/- 6.4 years, range 70-91 years) and 34 women (82.2 +/- 7.6 years, range 66-98 years). The relationship between the size of the abdominal aorta and various cardiovascular risk indicators such as calf:-brachial systolic pressure ratio, plasma cholesterol, triglycerides, and random blood glucose were examined. Abdominal aortic diameter correlated well with calf:-brachial systolic ratio measured by Doppler method over the posterior tibial artery and taking the lowest result of the right and left side (r = -0.28, P = 0.04). This correlation tended to be stronger in men (r = -0.55, P = 0.02) compared to women (r = -0.10, P = 0.57). However, the relationship tended to be confined to the systolic pressure in the left leg, raising the hypothesis that left-sided vascular disease is better related to aortic diameter, possibly due to a difference in the effects of reflected waves between the two sides. This needs further investigation. The contrast between the sexes was seen in the absence of any significant difference in resting blood pressure and calf:brachial systolic pressure ratio between the two. This finding suggests that the sex differences in the relationship between the size of the abdominal aorta and calf:brachial systolic pressure ratio are related to intrinsic properties of the arterial wall.

In vitro study of the anti-aggregating activity of two nitroderivatives of acetylsalicylic acid.

The antiplatelet activity of two new nitrocompounds, chemically related to acetylsalicylic acid (NCX 4215 and NCX 4016), was studied in vitro to verify the hypothetical dual action of these drugs. Both drugs, in a dose-dependent way, inhibited arachidonic acid-induced platelet aggregation and thromboxane A2 production, measured as thromboxane B2 concentration in whole blood. These effects are likely to be related to cyclo-oxygenase inhibition. NCX 4215 and NCX 4016 in a dose-dependent way inhibited also thrombin-induced aggregation of platelets pretreated with acetylsalicylic acid. These inhibitory effects are related to nitric oxide release and cGMP increase and significantly reversed by oxyhaemoglobin and methylene blue. Either as a cyclo-oxygenase inhibitor or as a nitric oxide donor, NCX 4016 proved to be significantly more potent than NCX 4215.

Effect of single and repeated doses of a new nitroderivative of acetylsalicylic acid on platelet TXA2 production in rats.

The effects of a new ASA-nitroderivative compound, NCX 4016 (ASA-NO2), on platelet TXA2 synthesis after single and repeated doses in the rat were investigated. Compared to ASA, cumulative doses of ASA-NO2 showed similar inhibitory effects on platelet TXA2 synthesis and significant increases in nitrite/nitrate plasma concentrations 1 h after the last drug administration: 24 h later nitrite/nitrate plasma levels returned to the control values, while serum TXA2 concentrations did not change. A time-course study after a single dose of ASA-NO2 showed a significant inhibition of platelet TXA2 production also 24 h after drug administration and a significant increase in nitrite/nitrate plasma levels until 10 h.

Antiaggregating and vasodilatory effects of a new nitroderivative of acetylsalicylic acid.

We studied in vitro the effects on platelet aggregation and vascular tone of a new nitrocompound (nitroxy-butyl-acetylsalicylate: NO-ASA). In order to elucidate any possible activity due to the release of nitric oxide or the inhibition of platelet cyclo-oxygenase we compared NO-ASA to acetylsalicylic acid. NO-ASA 1 mM inhibited arachidonic acid-induced platelet aggregation (basal 75.4 +/- 2.35%; NO-ASA 22 +/- 3.46%; M +/- SEM; P < 0.001; n = 6), but proved less active than acetylsalicylic acid (complete inhibition at 2 x 10(-5) M). NO-ASA also significantly reduced thrombin-induced (0.04-0.08 U/ml) platelet aggregation in acetylsalicylic acid-treated platelets (basal 70.5 +/- 1.7%; NO-ASA 35.4 +/- 2.2%; P < 0.001; n = 10; IC50 7 x 10(-5) M). Methylene blue reduced the effects of NO-ASA on thrombin-induced (NO-ASA 46.7 +/- 5.25%; NO-ASA+MB 59.1 +/- 4.3%; P < 0.01; n = 8), but not arachidonic acid-induced platelet aggregation. The inhibitory effects of NO-ASA on platelet aggregation were partially removed by oxyhaemoglobin. Platelet thromboxane A2 production (TXB2 concentration in the supernatant of the aggregate 35.38 +/- 7.81 ng/ml; n = 8), was totally abolished by acetylsalicylic acid (0.17 +/- 0.04 ng/ml; P < 0.001; n = 8) and reduced by NO-ASA (8.3 +/- 4.05 ng/ml; P < 0.01; n = 8). In vitro studies on isolated rat aortic rings showed NO-ASA 10(-3) M, but not ASA up to 10(-3) M, induce a dose dependent vasorelaxation (100% of epinephrine-induced contraction) both in intact and endothelium denuded arteries (IC50 5 x 10(-5) M). Addition of methylene blue reversed this relaxation. In conclusion these data demonstrate that NO-ASA acts through a double mechanism: a) by inhibiting cyclo-oxygenase and b) by releasing NO active on guanylyn cyclase both in platelets and in vascular smooth muscle cells.

Oxidized LDL and reduction of the antiaggregating activity of nitric oxide derived from endothelial cells.

Oxidized LDL has been observed to induce abnormalities in endothelial function which may be relevant for the progression of atherosclerotic lesions. We studied in vitro the possible effects of oxidized LDL on the antiaggregating activity of endothelial cells, which is dependent on release of prostacyclin and nitric oxide. We used an experimental model in which cultured human endothelial cells were placed in the aggregometer in contact with human platelets, after blockade of cyclo-oxygenase by adding acetylsalicylic acid. In this way the antiaggregant effect of endothelial cells was dependent on the release of nitric oxide alone; prevention of antiaggregant activity by preincubation of endothelial cells with 300 microM L-NG-mono-methylarginine confirmed this. When this system was used, endothelial cells (2-7.5 x 10(5)/ml) almost completely inhibited thrombin-induced (0.02-0.08 U/ml) platelet aggregation (2 x 10(8) platelets/ml), measured according to Born (11.1% +/- 8.5 vs 68.6% +/- 12.6, M +/- SD). This antiaggregating activity was reduced when slightly oxidized LDL 100 micrograms/ml (35.2% +/- 14.9, p < 0.001), but not native LDL 100 micrograms/ml (7.5% +/- 7.6), was added immediately before aggregation was induced. Incubation of endothelial cells with oxidized LDL 100 micrograms/ml for 1 h did not affect the antiaggregating capacity, unless oxidized LDL was present during aggregation (18.3% +/- 10.2 vs 35.8% +/- 9.6, p < 0.02). No significant direct effect of either oxidized or native LDL on stimulated platelet aggregation was observed. Our results indicate that slightly oxidized LDL can reduce the antiaggregating properties of the endothelium, probably by interaction with NO rather than through inhibition of its synthesis.