Effects of Alpha Lipoic Acid on Multiple Cytokines and Biomarkers and Recurrence of Atrial Fibrillation Within 1 Year of Catheter Ablation.

Catheter ablation (CA) is a procedure commonly used to restore sinus rhythm in patients with atrial fibrillation (AF). However, AF recurrence after CA remains a relevant clinical issue. We tested the effects of an oral antioxidant treatment (alpha lipoic acid [ALA]) on AF recurrence post-CA. Patients with paroxysmal AF have been enrolled in a randomized, prospective, double-blind, controlled placebo trial. After CA, patients have been randomly assigned to receive ALA oral supplementation (ALA group) or placebo (control group) and evaluated at baseline and after a 12-month follow-up: 73 patients completed the 12-month follow-up (ALA: 33 and control: 40). No significant difference has been detected between the 2 groups at baseline. Strikingly, 1 year after CA, ALA therapy significantly reduced serum markers of inflammation. However, there was no significant difference in AF recurrence events at follow-up comparing ALA with placebo group. Multivariate analysis revealed that the only independent prognostic risk factor for AF recurrence after CA is age. In conclusion, ALA therapy reduces serum levels of common markers of inflammation in ablated patients. Nevertheless, ALA does not prevent AF recurrence after an ablative treatment.

Assessing Nephrological Competence among Geriatricians: A Proof of Concept Internet Survey.

Chronic kidney disease (CKD) is highly prevalent in the elderly and negatively impacts survival and health status. Thus, nephrological competence is mandatory for a skilled geriatrician. The present study aimed to assess nephrological competence in a sample of geriatricians recruited through a web survey. To this aim, a 12-items questionnaire was produced by an expert panel of nephrologists and geriatricians and was available online for members of the Italian Society of Gerontology and Geriatrics (SIGG). Two-hundred-eighty-seven geriatricians volunteered to fill in the questionnaire. The majority of them indirectly estimated the glomerular filtration rate (GFR) using mainly the Cockroft-Gault (C-G) formula. Selected nephrological exams, such as urinary Na and serum D-vitamin measurements, did not qualify as routine exams although the majority of geriatricians supplemented their patients with fat-soluble secosteroids. Ten percent of geriatricians asked for nephrological consultation only for stage 5 CKD patients and 30,9% only for stage 4 or 5. Erythropoietin supplementation was common practice for the majority of geriatricians, while only one third of them systematically used a procedure intended to prevent the contrast induced nephropathy (CIN). Finally, an alleged 50% adherence to the international guidelines for the management of CKD patients emerged from the questionnaire. Overall, results from this survey strongly recommend promoting nephrological education among geriatricians. Didactic standards for in training geriatricians need to be updated and the cooperation between geriatrics and nephrological societies promoted.

Insulin resistance and systemic inflammation, but not metabolic syndrome phenotype, predict 9 years mortality in older adults.

BACKGROUND: Although metabolic syndrome (MS) is a typical condition of middle-aged/older person, the association between MS and mortality risk has not been confirmed in people over 65 years. We hypothesized that while in the elderly MS phenotype might lose its value in predicting mortality risk, the two core factors of MS, i.e. insulin resistance (IR) and low grade systemic inflammation (LGSI) would not. METHODS: 1011 community-dwelling older individuals (InCHIANTI study) were included. MS phenotype was defined by NCEP-ATP-III criteria. IR was calculated by HOMA; high-sensitivity C reactive protein was measured by ELISA. Subjects were divided into four groups based on presence/absence of IR (HOMA ≥ 2.27) and LGSI (hs-CRP ≥ 3 g/L): Group 1: no IR/LGSI (reference); Group 2: LGSI only; Group 3: IR only; Group 4: IR + LGSI. Hazard Ratios (HR) for 9-years cardiovascular (CVD) and total mortality, according to IR/LGSI groups, were estimated in subjects with (n.311) and without MS by Cox model. RESULTS: 31.8% of subjects with MS phenotype had no IR, 45.3% had no LGSI; moreover, 51% of subjects with both IR and LGSI didn't display the MS phenotype. MS phenotype was not associated with CVD (HR: 1.29; 95%C.I.:0.92-1.81) or total (HR: 1.07; 95%C.I.:0.86-1.34) mortality risk, whereas the presence of IR plus LGSI was associated with increased CVD (no MS: HR 2.07, 95%CI: 1.12-3.72; MS: HR 9.88, 95%CI: 2.18-4), and overall (no MS: HR 1.72, 95%CI: 1.001-3.17; MS: HR 1.51, 95%CI: 1.02-2.28) mortality risk. The presence of IR (HR: 6.90, 95%CI: 1.45-32) or LGSI (HR 7.56, 95%CI: 1.63-35) was associated with CVD mortality, only among individuals with MS phenotype. CONCLUSIONS: Among community-dwelling older individuals, IR and LGSI, but not MS phenotype, was associated with 9-years overall and CVD mortality risk. Since a reduced "overlap" between MS phenotype and its physiopathological core (IR and LGSI) might be present with aging, we suggest that the definition of MS might be more holistic in advanced age, and probably comprise the measurement of IR and LGSI.

Association of plasma selenium concentrations with total IGF-1 among older community-dwelling adults: the InCHIANTI study.

BACKGROUND & AIMS: Insulin-like growth factor (IGF-1) stimulates cell proliferation and inhibits cell apoptosis. Recent studies underline its importance as anabolic hormone and nutritional marker in older individuals. IGF-1 synthesis and bioactivity are modulated by nutritional factors including selenium intake. However, whether circulating IGF-1 levels are positively influenced by plasma selenium, one of the most important human antioxidants, is still unknown. METHODS: Selenium and total IGF-1 were measured in 951 men and women ≥ 65 years from the InCHIANTI study, Tuscany, Italy. RESULTS: Means (SD) of plasma selenium and total IGF-1 were 0.95 (0.15) µmol/L and 113.4 (31.2)ng/mL, respectively. After adjustment for age and sex, selenium levels were positively associated with total IGF-1 (ß±SE: 43.76±11.2, p=0.0001). After further adjustment for total energy and alcohol intake, serum alanine aminotransferase (ALT), congestive heart failure, selenium remained significantly associated with IGF-1 (ß±SE: 36.7±12.2, p=0.003). The association was still significant when IL-6 was introduced in the model (ß±SE: 40.1±12.0, p=0.0008). CONCLUSIONS: We found an independent, positive and significant association between selenium and IGF-1 serum levels in community dwelling older adults.

Evidence for anti-inflammatory effects of combined administration of vitamin E and C in older persons with impaired fasting glucose: impact on insulin action.

OBJECTIVE: Vitamin E and C given separately improve insulin sensitivity due to an inhibitory effect on oxidative stress and inflammation, however their combined effect on glucose control and inflammation is unknown. To investigate combined effect of Vitamin E and C in elderly with Impaired Fasting Glucose (IFG) on insulin action and substrate oxidation. DESIGN: Controlled-trial administration of Vitamin E (1000 mg/day) and Vitamin C (1000 UI/day) for four weeks. Hyperinsulinemic euglycemic glucose clamp was performed before and following supplementation. SETTING: Out-patient clinic. PARTICIPANTS: Thirteen older men with IFG. MAIN OUTCOME PARAMETERS: Variations in whole body glucose disposal (WBGD), anti-oxidant, and inflammatory cytokines plasma levels. RESULTS: An increase in plasma Vitamin E (8.3 + 0.8 vs. 64.9 + 2.1 micromol/l; p < 0.001] and C (35.9 + 5.4 vs. 79.4 + 7.4 micromol/l; p < 0.001) was found. Vitamin administration reduced insulin, glucose, lipid, TNF-alpha and [8-]isoprostane levels. Increase in plasma vitamin E levels correlated with decline in both plasma [8-]isoprostane levels (r = -0.58; p = 0.048) and TNF-alpha levels (r = - 0.62; p = 0.025), while no correlations were found for Vitamin C. Whole body glucose disposal (WBGD) (22.7 + 0.6 vs. 30.4 + 0.8 mmol x kg-1 x min-1; p = 0.001) and non-oxidative glucose metabolism rose after supplementation. Rise in plasma levels of Vitamin C and E correlated with WBGD. Multivariate linear regression models showed independent associations among the change in Vitamin E and the decline in TNF-alpha and [8-]isoprostane levels. CONCLUSIONS: Combined administration of Vitamin E and C lowered inflammation and improved insulin action through a rise in non-oxidative glucose metabolism.

Effects of soy isoflavones on endothelial function in healthy postmenopausal women.

OBJECTIVE: To evaluate the effects of soy isoflavone administration on endothelial function in healthy postmenopausal women. DESIGN: Sixty naturally postmenopausal women were randomly assigned to receive isoflavone or placebo tablets for 6 months. Endothelium-dependent vasodilatation was measured by brachial reactivity technique along with levels of plasma soluble intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, P-selectin and soluble thrombomodulin, von Willebrand factor, and tissue plasminogen activator. Differences between endothelium-dependent and endothelium-independent vasodilatation were assessed by evaluating brachial reactivity parameters after reactive hyperemia and after sublingual administration of nitroglycerin; furthermore, in the active group, the effect of isoflavones was also evaluated during the intra-arterial infusion of N-monomethyl-L-arginine. Serum levels of lipids [high-density lipoprotein and low-density lipoprotein cholesterol, triglycerides and lipoprotein(a)] and hemostatic factors (prothrombin, fibrinogen, plasminogen activator inhibitor-1, and fibrin D-dimer) were also measured. To confirm the absorption of isoflavones, their blood concentrations were determined. RESULTS: Isoflavone treatment versus placebo was associated with a significant improvement in endothelium-dependent vasodilatation but had no impact on endothelial-independent arterial diameter and flow. Intra-arterial infusion of N-monomethyl-L-arginine inhibited the significant effect of isoflavones on endothelium-mediated vasodilatation. Furthermore, isoflavone group experienced statistically significant reductions in plasma concentrations of ICAM-1, VCAM-1, and E-selectin. Levels of soluble thrombomodulin, von Willebrand factor, tissue plasminogen activator, lipids, and hemostatic factors did not change significantly throughout the study in both groups. CONCLUSIONS: Our findings suggest a positive influence of soy isoflavones on endothelial function in healthy postmenopausal women as evidenced by an improvement in endothelium-dependent vasodilatation and a reduction in plasma adhesion molecule levels.

Evidence for reduction of pro-atherosclerotic properties in platelets from healthy centenarians.

The aim of the present study was to investigate if aging is associated with platelet membrane modifications possibly related with cellular activation and hyperaggregability and if platelets from centenarians show different properties which might play a role in successful aging and longevity. Platelet plasma membranes were obtained from 60 healthy subjects, divided into four groups according to the age range: (1) 21-39 years; (2) 40-59 years; (3) 60-79 years; (4) centenarians (>/=100 years). Both centenarians and control subjects were submitted to the following inclusion criteria: liver, kidney, and thyroid function tests within the normal range; absence of history of diabetes, hypertension or coronary heart disease; no signs of edema or dehydration; no drug or vitamin supplement in the 4 weeks before the study; absence of Alzheimer's disease or secondary dementia. The following determinations were performed: lipid peroxide levels (Lp) evaluated by the measurement of thiobarbituric acid (TBA) reactivity, fluidity studied by the fluorescence anisotropy of the probe 1-(4-trimethylaminophenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH), Na(+)/K(+)-ATPase activity measured by the method of Kitao and Hattori, and sialic acid (SA) content evaluated by the periodate-thiobarbituric acid method. Centenarians showed: (i) Lp concentrations lower than elderly subjects; (ii) increased Na(+)/K(+)-ATPase activity compared with adult and elderly subjects; (iii) higher TMA-DPH anisotropy than elderly subjects; (iv) SA content similar to the young and adult groups.The present work found deep platelet membrane modifications in centenarians compared with elderly subjects. These changes are likely associated with a decreased platelet activation and therefore might exert a protective role against cardiovascular accidents, as platelet activation is a key event in the initiation and progression of arteriosclerosis.

Role of magnesium in insulin action, diabetes and cardio-metabolic syndrome X.

Magnesium (Mg) is one of the most abundant ions present in living cells and its plasma concentration is remarkably constant in healthy subjects. Plasma and intracellular Mg concentrations are tightly regulated by several factors. Among them, insulin seems to be one of the most important. In vitro and in vivo studies have demonstrated that insulin may modulate the shift of Mg from extracellular to intracellular space. Intracellular Mg concentration has also been shown to be effective in modulating insulin action (mainly oxidative glucose metabolism), offset calcium-related excitation-contraction coupling, and decrease smooth cell responsiveness to depolarizing stimuli. A poor intracellular Mg concentration, as found in noninsulin-dependent diabetes mellitus (NIDDM) and in hypertensive patients, may result in a defective tyrosine-kinase activity at the insulin receptor level and exaggerated intracellular calcium concentration. Both events are responsible for the impairment in insulin action and a worsening of insulin resistance in noninsulin-dependent diabetic and hypertensive patients. By contrast, in NIDDM patients daily Mg administration, restoring a more appropriate intracellular Mg concentration, contributes to improve insulin-mediated glucose uptake. The benefits deriving- from daily Mg supplementation in NIDDM patients are further supported by epidemiological studies showing that high daily Mg intake are predictive of a lower incidence of NIDDM. In conclusion, a growing body of studies suggest that intracellular Mg may play a key role in modulating insulin-mediated glucose uptake and vascular tone. We further suggest that a reduced intracellular Mg concentration might be the missing link helping to explain the epidemiological association between NIDDM and hypertension.

Postprandial endothelial activation in healthy subjects and in type 2 diabetic patients: role of fat and carbohydrate meals.

OBJECTIVES: To compare the effect of a high-fat meal and a high-carbohydrate meal (pizza), with and without antioxidant vitamins, on endothelial activation in healthy subjects and in patients with type 2 diabetes mellitus. BACKGROUND: The postprandial state is becoming increasingly acknowledged to affect some early events of atherogenesis. METHODS: In a randomized, observer-blinded, crossover study, 20 newly diagnosed type 2 diabetic patients and 20 age- and gender-matched healthy subjects received two meals at one-week intervals: a high-fat meal (760 calories) and an isoenergetic high-carbohydrate meal (non-cheese pizza). In all subjects, the same meals were repeated immediately following ingestion of vitamin E, 800 IU, and ascorbic acid, 1,000 mg. RESULTS: In normal subjects, the high-fat meal increased the plasma levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), which were prevented by vitamins. No change in these parameters occurred after pizza ingestion or pizza ingestion with vitamins. In diabetic patients, basal concentrations of glucose, cytokines and adhesion molecules were significantly higher than in nondiabetic controls. Both meals significantly increased cytokine and adhesion molecule levels, but the increase was more sustained following the high-fat meal. There was no significant change from baseline when vitamin supplementation accompanied each meal. There was a relationship between changes in serum triglycerides and changes in TNF-alpha (r = 0.39, p < 0.01), IL-6 (r = 0.28, p < 0.05) and VCAM-1 (r = 0.25, p < 0.05), and between changes in plasma glucose and changes in IL-6 (r = 0.36, p < 0.01) and ICAM-1 (r = 0.31, p < 0.02). CONCLUSIONS: An oxidative mechanism mediates endothelial activation induced by post-meal hyperlipidemia and hyperglycemia.