Weight loss facilitates reduction of left ventricular mass in obese hypertensive patients: The Campania Salute Network.

BACKGROUND AND AIMS: Reduction of left ventricular mass index (LVMi) during antihypertensive treatment is less likely to occur in obese subjects. The aim of the study was to assess whether weight loss influences reduction of LVMi in treated, obese, hypertensive patients. METHODS AND RESULTS: From the Campania Salute Network registry, we identified 1546 obese hypertensive patients (50 ± 9 years, 43% women) with more than 12 months follow-up. Echocardiographic reduction of LVMi was considered as achievement of normal values (<47 g/m2.7 in women or <50 g/m2.7 in men) or a reduction of ≥10% during follow-up. Weight loss was considered as ≥5% reduction in body weight, and occurred in 403 patients (26%) during a median follow-up of 50 months (IQrange:31-93). Median weight loss was 8.6% (IQrange:6.5-12). Patients with weight loss had higher baseline body mass index (p < 0.05), while there was no difference in age, sex, duration of hypertension, prevalence of diabetes, metabolic syndrome and average blood pressure during follow-up. During follow-up, 152 patients (9.8%) exhibited reduction of LVMi. Reduction of LVMi was more frequent (12.9% vs 9.1%, p < 0.030) in patients losing weight than in those who did not. In logistic regression analysis, weight loss was associated with reduction of left ventricular mass index (OR 1.51 [95%CI 1.02-2.23], p = 0.039), independent of significant associations with younger age, lower average systolic blood pressure during follow-up, longer follow-up time and higher LVMi at baseline. CONCLUSION: In treated obese hypertensive patients, weight loss during follow-up promotes significant reduction of LVMi, independent of baseline characteristics and blood pressure control.

Is increased uric acid a risk factor or a defensive response? The Campania Salute Network.

BACKGROUND AND AIMS: Circulating uric acid (UA) is positively associated with body mass index (BMI), blood glucose, blood pressure (BP), markers of inflammation, and altered lipid profile. UA has also anti-oxidative properties which might be beneficial for cardiovascular (CV) system. It is still debated whether or not UA is independently associated with increased CV morbidity and/or mortality. METHODS AND RESULTS: We studied prognostic impact of UA in 8833 hypertensive adults (mean age 53 ± 12 yrs, 3857 women) from the Campania Salute Network, without prevalent CV disease and more than stage 3 CKD. We calculated standardized UA Z-score, adjusted for age, sex, glomerular filtration rate, and BMI. Low and high UA and UA Z-score quartiles were compared to the 2 middle quartiles assumed to be "normal". Prevalence of obesity and diabetes was higher in low and high than in normal UA Z-score group (all p < 0.001). Systolic BP, left ventricular mass, carotid intima thickness were significantly higher and ejection fraction was reduced in the presence of high UA Z-score (all p < 0.001). Over 33-months average follow-up, incident major CV end-points (MACE) were not significantly different among low, normal and high UA or UA Z-score. In the latter analysis, however, incident MACE tended to be more frequent in the low than the high UA Z-score. Despite the results of multivariable analyses, the effect of less aggressive therapy in low UA Z-score cannot be excluded with certainty. CONCLUSION: In treated hypertensive patients, high levels of UA normalized for major biological determinants do not independently predict CV outcome. CLINICALTRIALS. GOV IDENTIFIER: NCT02211365.

Opposite effects of ß2-adrenoceptor gene deletion on insulin signaling in liver and skeletal muscle.

BACKGROUND AND AIM: ß2-Adrenoceptors (ß2-ARs) are G protein-coupled receptors (GPCRs) expressed in the major insulin target tissues. The interplay between ß2-AR and insulin pathways is involved in the maintenance of glucose homeostasis. The aim of this study was to explore the consequences of ß2-ARs deletion on insulin sensitivity and insulin signaling cascade in metabolically active tissues. METHODS AND RESULTS: We evaluated glucose homeostasis in skeletal muscle and liver of ß2-AR-null mice (ß2-AR-/-) by performing in vivo (glucose tolerance test and insulin tolerance test) and ex vivo (glucose uptake and glycogen determination) experiments. ß2-AR gene deletion is associated with hepatic insulin resistance and preserved skeletal muscle insulin sensitivity. Importantly, we demonstrate that hepatic ß2-AR regulates insulin-induced AKT activation via Grb2-mediated SRC recruitment through a Gi-independent mechanism. CONCLUSIONS: ß-AR stimulation contributes to the development of early stages of insulin resistance progression in the liver. Our findings indicate that the cross-talk between ß2-AR and insulin signaling represents a fundamental target towards the development of novel therapeutic approaches to treat type 2 diabetes and metabolic syndrome.

Efficacy and safety of glucagon-like peptide-1 agonists on macrovascular and microvascular events in type 2 diabetes mellitus: A meta-analysis.

AIMS: Glucagon-like peptide-1 (GLP-1) agonists improve glycaemic control in type 2 diabetes mellitus (DM). Outcome trials investigating macro and microvascular effects of GLP-1 agonists reported conflicting results. The aim of this study was to assess, in a meta-analysis, the effects of GLP-1 agonists on mortality, major nonfatal cardiovascular (CV) events, renal and retinal events. DATA SYNTHESIS: MEDLINE, Cochrane, ISI Web of Science, SCOPUS and ClinicalTrial.gov databases were searched for articles published until June 2017. Randomized trials enrolling more than 200 patients, comparing GLP-1 versus placebo or active treatments in patients with DM, and assessing outcomes among all-cause death, CV death, MI, stroke, HF, diabetic retinopathy and nephropathy were included. 77 randomized trials enrolling 60,434 patients were included. Compared to control, treatment with GLP-1 significantly reduced the risk of all-cause death (RR: 0.888; CI: 0.804-0.979; p = 0.018) and the risk of CV death (RR: 0.858; CI: 0.757-0.973; p = 0.017). GLP-1 agonists did not affect the risk of MI (RR: 0.917; CI: 0.830-1.014; p = 0.092) as well as the risk of stroke (RR: 0.882; CI: 0.759-1.023; p = 0.097), HF (RR: 0.967; CI: 0.803-1.165; p = 0.725), retinopathy (RR: 1.000; CI: 0.807-1.238; p = 0.997) and nephropathy (RR: 0.866; CI: 0.625-1.199; p = 0.385). CONCLUSIONS: Treatment with GLP-1 agonists in DM patients is associated with a significant reduction of all cause and CV mortality.

Vitamin D deficiency and clinical outcome in patients with chronic heart failure: A review.

AIM: The aim of this review was to summarize evidence on the role of Vitamin D deficiency in heart failure (HF), from pathophysiological mechanisms to clinical effects of Vitamin D supplementation. DATA SYNTHESIS: Chronic HF secondary to left ventricular (LV) systolic dysfunction is a growing health problem, still associated with poor clinical outcome. In recent years, experimental and epidemiological evidence focused on the role of Vitamin D in HF. Cross sectional studies demonstrated that prevalence of HF is increased in patients with Vitamin D deficiency or parathyroid hormone (PTH) plasma level increase, whereas longitudinal studies showed enhanced risk of developing new HF in patients with Vitamin D deficiency. In addition, in patients with established HF, low plasma levels of Vitamin D are associated with worsening clinical outcome. Yet, clinical studies did not definitively demonstrate a benefit of Vitamin D supplementation for preventing HF or ameliorating clinical outcome in patients with established HF. CONCLUSIONS: Despite convincing experimental and epidemiological data, treatment with Vitamin D supplementation did not show clear evidence of benefit for preventing HF or influencing its clinical course. Ongoing clinical studies will hopefully shed lights on the effects of Vitamin D supplementation on clinical endpoints along the spectrum of HF.

New small molecules, ISA27 and SM13, inhibit tumour growth inducing mitochondrial effects of p53.

BACKGROUND: p53 is a transcription factor with tumour suppressor properties, which is able to induce mitochondrial apoptosis independently of its transcriptional activity. We recently synthesised two new compounds (ISA27 and SM13), which block p53-MDM2 interaction and induce apoptosis in p53 wild-type (WT) tumour cells. The aim of this study was to verify the effectiveness of these compounds in tumours carrying a mutated form of p53 gene with no transcriptional activity. METHODS: In vitro we evaluated the effectiveness of our compounds in cancer cell lines carrying WT, mutated and null p53 gene. In vivo study was performed in Balb/c nude mice and the mitochondrial-dependent apoptotic signalling was evaluated by western blot. RESULTS: Both ISA27 and SM13 reduced cell proliferation and induced apoptosis in vitro in cells carrying either p53 WT or mutated gene, suggesting that its effect is independent from p53 transcriptional activity. On the contrary, SM13 had no effect in a p53 null cell line. In vivo, ISA27 and SM13 induced cancer cell death in a dose-dependent manner through the activation of the mitochondrial-dependent death signalling in p53-mutated cells. In vivo, SM13 reduced tumour growth. CONCLUSIONS: Our study proposes SM13 as anticancer compound to use for the treatment of p53-dependent tumours, even in the absence of p53 transcriptional activity.

Serum uric acid and its relationship with metabolic syndrome and cardiovascular risk profile in patients with hypertension: insights from the I-DEMAND study.

BACKGROUND AND AIMS: The independent role of serum uric acid (SUA) as a marker of cardio-renal risk is debated. The aim of this study was to assess the relationship between SUA, metabolic syndrome (MS), and other cardiovascular (CV) risk factors in an Italian population of hypertensive patients with a high prevalence of diabetes. METHODS AND RESULTS: A total of 2429 patients (mean age 62 ± 11 years) among those enrolled in the I-DEMAND study were stratified on the basis of SUA gender specific quartiles. MS was defined according to the NCEP-ATP III criteria, chronic kidney disease (CKD) as an estimated GFR (CKD-Epi) <60 ml/min/1.73 m(2) or as the presence of microalbuminuria (albumin-to-creatinine ratio ≥2.5 mg/mmol in men and ≥3.5 mg/mmol in women). The prevalence of MS, CKD, and positive history for CV events was 72%, 43%, and 20%, respectively. SUA levels correlated with the presence of MS, its components, signs of renal damage and worse CV risk profile. Multivariate logistic regression analysis revealed that SUA was associated with a positive history of CV events and high Framingham risk score even after adjusting for MS and its components (OR 1.10, 95% CI 1.03-1.18; P = 0.0060; OR 1.28, 95% CI 1.15-1.42; P < 0.0001). These associations were stronger in patients without diabetes and with normal renal function. CONCLUSIONS: Mild hyperuricemia is a strong, independent marker of MS and high cardio-renal risk profile in hypertensive patients under specialist care. Intervention trials are needed to investigate whether the reduction of SUA levels favorably impacts outcome in patients at high CV risk.

Functional foods and cardiometabolic diseases* International Task Force for Prevention of Cardiometabolic Diseases.

Mounting evidence supports the hypothesis that functional foods containing physiologically-active components may be healthful. Longitudinal cohort studies have shown that some food classes and dietary patterns are beneficial in primary prevention, and this has led to the identification of putative functional foods. This field, however, is at its very beginning, and additional research is necessary to substantiate the potential health benefit of foods for which the diet-health relationships are not yet scientifically validated. It appears essential, however, that before health claims are made for particular foods, in vivo randomized, double-blind, placebo controlled trials of clinical end-points are necessary to establish clinical efficacy. Since there is need for research work aimed at devising personalized diet based on genetic make-up, it seems more than reasonable the latter be modeled, at present, on the Mediterranean diet, given the large body of evidence of its healthful effects. The Mediterranean diet is a nutritional model whose origins go back to the traditional dietadopted in European countries bordering the Mediterranean sea, namely central and southern Italy, Greece and Spain; these populations have a lower incidence of cardiovascular diseases than the North American ones, whose diet is characterized by high intake of animal fat. The meeting in Naples and this document both aim to focus on the changes in time in these two different models of dietary habits and their fall out on public health.

Primary prevention with statins and incident diabetes in hypertensive patients at high cardiovascular risk.

BACKGROUND AND AIMS: The ESC/ESH guidelines for arterial hypertension recommend using statins for patients with high cardiovascular (CV) risk for both secondary and primary prevention. A recent meta-analysis, combining previous studies on statins, concluded that they are associated with a 9% increased risk of incident type 2 diabetes mellitus (DM). There is no information on whether statins increase incidence of DM in primary prevention. METHOD AND RESULTS: We evaluated risk of incident DM in relation to statin prescription in 4750 hypertensive, non-diabetic outpatients (age 58.57 ± 9.0 yrs, 42.3% women), from the CampaniaSalute Network, without chronic kidney disease more than grade 3, free of prevalent CV disease and with at least 12 months of follow-up. DM was defined according to ADA criteria. At the end of follow-up period (55.78 ± 42.5 months), 676 patients (14%) were on statins. These patients were older (62.54 ± 7.3 vs 57.91 ± 9.1 yrs; p < 0.0001), more often female (49% vs 41.2%; p = 0.0001), with higher initial total cholesterol (217.93 ± 44.3 vs 205.29 ± 36.6 mg/dl), non-HDL cholesterol (167.16 ± 44.5 vs 155.18 ± 36.7 mg/dl) and triglycerides (150.69 ± 85.2 vs 130.98 ± 72.0 mg/dl; all p < 0.0001) than patients no taking statins, without other differences in clinical and laboratory characteristics. At the end of follow-up, prevalence of DM was 18.1% among patients on statins and 7.2% among those without lipid-lowering therapy (p < 0.0001). However, incident DM was 10.2% in patients on statins and 8.7% in those free of statin therapy (NS). CONCLUSION: In real-life outpatient environment, statin prescription for primary prevention is not associated with increased risk of incident DM.

Changes in serum uric acid levels and cardiovascular events: a meta-analysis.

BACKGROUND AND AIMS: The association between serum uric acid (SUA) levels and cardiovascular (CV) risk or all-cause death has been repeatedly reported. However, it has not been assessed whether reduction of SUA levels is associated with reduced CV risk. The aim of the current study was to evaluate the relationship between changes of SUA levels and CV events as well as all-cause death. METHODS AND RESULTS: Randomised trials reporting SUA at baseline and at the end of follow-up and clinical end-points (all-cause death, myocardial infarction (MI), stroke, heart failure (HF) and CV death) were included in the study. Meta-regression analysis was performed to test the relationship between SUA changes and clinical end-points. Eleven trials enrolling 21,373 participants followed up for 2.02 ± 1.76 years and reporting 4533 events were included. In meta-regression analysis, no relationship between SUA changes from baseline to end of follow-up and the composite outcome including CV death, stroke, MI and HF was found (change in Tau(2) (t) = -0.64; p Tau (p) = 0.541). Similarly, no relationship was found between SUA changes and single components of the composite outcome (MI: t = -0.83; p = 0.493; stroke: t = 0.46; p = 0.667; HF: t = 2.44; p = 0.162; CV death: t = -0.54; p = 0.614) and all-cause death (t = -0.72; p = 0.496). Results were confirmed by sensitivity analysis. No heterogeneity among studies or publication bias was detected. CONCLUSIONS: Changes in SUA levels observed during pharmacologic treatments do not predict the risk of all-cause death or CV events. As SUA levels are associated with increased CV risk, additional studies with direct xanthine-oxidase inhibitors are requested.

Use of the PARO robot as a social mediator in a sample of children with neurodevelopmental disorders and typical development.

Background: Social robotics is a research field aimed at providing robots with skills related to social behavior and natural human interaction. Many studies have demonstrated the efficacy of these robots as socio-communicative mediators. Others have used them to create a new communication channel and promote social interaction in chil-dren with autism spectrum disorder (ASD). For children with ASD prolonged interpersonal interaction can sometimes generate extreme frustration. They may find it difficult to focus their attention and learn social skills. The robot may therefore become a reliable and more predictable technological intermediary for the child. Methods: Our study involved the use of the PARO seal robot as a social mediator in groups of children with neurodevelopmental disorders. We aimed to investigate whether the social robot could facilitate relationships with adults in children with neurodevelopmental disorders by comparing their interactions with those of typically developing children. Results: The results of our research partially confirm what has been reported in the existing literature, while introducing some innovations that could be addressed by future research. The results of the statistical analysis show a positive correlation in the 'interaction' dimension and the presence of the PARO seal in subjects diagnosed with autism without intellectual impairment. These data highlight the PARO robot's ability to facilitate communication and social. Conclusions: The results of the present study confirm that social robotics can be a valid tool to improve socio-communication skills in clinical samples of children with autism without intellectual impai-rment.

Effects of tissue factor induced by oxygen free radicals on coronary flow during reperfusion.

Tissue factor is a transmembrane protein that activates the extrinsic coagulation pathway by binding factor VII. Endothelial cells, being in contact with circulating blood, do not normally express tissue factor. Here we provide evidence that oxygen free radicals induce tissue factor messenger RNA transcription and expression of tissue factor procoagulant activity in endothelial cells in culture. Isolated, perfused rabbit hearts exposed to exogenous oxygen free radicals also showed a marked increase in tissue factor activity within the coronary circulation. Furthermore, in ex vivo and in vivo hearts subjected to ischemia and reperfusion, a condition associated with a production of oxygen free radicals in large amounts, a marked increase in tissue factor activity occurred. This phenomenon could be abolished by oxygen radical scavengers. This increase in tissue factor activity during postischemic reperfusion was accompanied by a significant decrease in coronary flow, suggesting that increase in tissue factor activity with the consequent activation of the coagulation cascade might impair coronary flow during reperfusion and possibly contribute to the occurrence of reperfusion injury.

Cardiac performance during exercise in hypertensive patients without ventricular hypertrophy.

BACKGROUND: Reduced systolic reserve on effort may be present in subjects with hypertension but no evidence of hypertensive cardiomyopathy. We assessed the determinants of abnormal cardiac performance during exercise in hypertensive patients without left ventricular hypertrophy. MATERIALS AND METHODS: Thirty-five newly diagnosed, never-treated-earlier hypertensive patients without definite indication for left ventricular hypertrophy at echocardiography underwent radionuclide ambulatory monitoring of left ventricular function at rest and during upright bicycle exercise testing. RESULTS: The patients were classified into two groups according to their ejection fraction response to exercise. In 21 patients (group 1), the ejection fraction increased > or = 5% with exercise and in 14 patients (group 2), the ejection fraction either increased < 5% or decreased with exercise. Patients of group 1 had lower peak filling rate at rest and less augmentation in end-diastolic volume during exercise (both P < 0.01) when compared with patients of group 2. A significant relationship between the magnitude of change in ejection fraction with exercise and both peak filling rate at rest (r = 0.58, P < 0.01) and exercise-induced change in end-diastolic volume (r = 0.45, P < 0.01) was found. CONCLUSIONS: In newly diagnosed, never-treated-earlier hypertensive subjects with no evidence of hypertensive cardiomyopathy, the cardiac response to exercise is dependent on adequate diastolic filling volume to maintain systolic performance.

Endothelial alpha1-adrenoceptors regulate neo-angiogenesis.

BACKGROUND AND PURPOSE: Intact endothelium plays a pivotal role in post-ischaemic angiogenesis. It is a phenomenon finely tuned by activation and inhibition of several endothelial receptors. The presence of alpha(1)-adrenoceptors on the endothelium suggests that these receptors may participate in regenerative phenomena by regulating the responses of endothelial cells involved in neo-angiogenesis. EXPERIMENTAL APPROACH: We evaluated the expression of the subtypes of the alpha(1)-adrenoceptor in isolated endothelial cells harvested from Wistar-Kyoto (WKY) rats. We explored the possibility these alpha(1)-adrenoceptors may influence the pro-angiogenic phenotype of endothelial cells in vitro. In vivo, we used a model of hindlimb ischaemia in WKY rats, to assess the effects of alpha(1) adrenoceptor agonist or antagonist on angiogenesis in the ischaemic hindlimb by laser Doppler blood flow measurements, digital angiographies, hindlimb perfusion with dyed beads and histological evaluation. KEY RESULTS: In vitro, pharmacological antagonism of alpha(1)-adrenoceptors in endothelial cells from WKY rats by doxazosin enhanced, while stimulation of these adrenoceptors with phenylephrine, inhibited endothelial cell proliferation and DNA synthesis, ERK and retinoblastoma protein (Rb) phosphorylation, cell migration and tubule formation. In vivo, we found increased alpha(1)-adrenoceptor density in the ischaemic hindlimb, compared to non-ischaemic hindlimb, suggesting an enhanced alpha(1)-adrenoceptor tone in the ischaemic tissue. Treatment with doxazosin (0.06 mg kg(-1) day(-1) for 14 days) did not alter systemic blood pressure but enhanced neo-angiogenesis in the ischaemic hindlimb, as measured by all our assays. CONCLUSIONS: Our findings support the hypothesis that the alpha(1)-adrenoceptors in endothelial cells provide a negative regulation of angiogenesis.

Differential effects of insulin on splanchnic and peripheral glucose disposal after an intravenous glucose load in man.

The present study was designed to investigate the mechanisms by which insulin regulates the disposal of an intravenous glucose load in man. A combined tracer-hepatic vein catheter technique was used to quantitate directly the components of net splanchnic glucose balance (NSGB), i.e., splanchnic glucose uptake and hepatic glucose output, and peripheral (extrasplanchnic) glucose uptake. Four different protocols were performed: (a) intravenous infusion of glucose alone (6.5 mg kg(-1) min(-1)) for 90 min (control group); (b) glucose plus somatostatin (0.6 mg/h) and glucagon (0.8 ng kg(-1) min(-1); (c) glucose plus somatostatin, glucagon, and insulin (0.15 mU kg(-1) min(-1)); and (d) glucose plus somatostatin, glucagon, and insulin (0.4 m U kg(-1) min(-1)). In groups 2-4, arterial blood glucose was raised to comparable levels to those of controls ( approximately 170 mg/dl) by a variable glucose infusion. In the control group, plasma insulin levels reached 40 muU/ml at 90 min. NSGB switched from a net output of 1.71+/-0.13 to a net uptake of 1.5-1.6 mg kg(-1) min(-1) due to a 90-95% suppression of hepatic glucose output (P < 0.01) and a 105-130% elevation of splanchnic glucose uptake (from 0.78+/-0.13 to 1.6-1.8 mg kg(-1) min(-1); P < 0.01). Peripheral glucose uptake rose by 150-160% (P < 0.01). In group 2, plasma insulin fell to <5 muU/ml. Net splanchnic glucose output initially rose twofold but later returned to basal values. This response was entirely accounted for by similar changes in hepatic glucose output since splanchnic glucose uptake remained totally unchanged in spite of hyperglycemia. In contrast, peripheral glucose uptake rose consistently by 100% (P < 0.01) despite insulin deficiency. In an additional group of experiments, glucose metabolism by the forearm muscle tissue was quantitated during identical conditions to those of group 2 (hyperglycemia plus insulin deficiency). Both the arterial-deep venous blood glucose difference and forearm glucose uptake increased markedly by 300-400% (P < 0.05 - <0.01). In group 3, plasma insulin was maintained at near-basal, peripheral levels (12-14 muU/ml). Hepatic glucose output decreased slightly by 35-40% (P < 0.05) while splanchnic glucose uptake remained unchanged. Consequently, the net glucose overproduction seen in group 2 was totally prevented although NSGB still remained as a net output. In group 4, peripheral insulin levels were similar to those of the control group (35-40 muU/ml). The suppression of hepatic glucose output was more pronounced (60-65%) and splanchnic glucose uptake rose consistently by 65% (P < 0.01). Consequently, NSGB did not remain as a net output but eventually switched to a small uptake (0.3 mg kg(-1) min(-1)). Peripheral glucose uptake rose to the same extent as in controls. IT IS CONCLUDED THAT: (a) the suppressive effect of hyperglycemia on hepatic glucose output is strictly dependent on the degree of hepatic insulinization; (b) insulin plays an essential role in promoting splanchnic glucose uptake after an intravenous glucose load whereas hyperglycemia per se is totally unable to activate this process; (c) peripheral glucose uptake is markedly stimulated by hyperglycemia even in the face of insulin deficiency. Direct evidence also demonstrates that the skeletal muscle is involved in this response. Our data, thus, indicate that insulin rather than hyperglycemia regulates splanchnic glucose disposal in man. On the other hand, hyperglycemia per se appears to be an important regulator of glucose disposal by peripheral tissues.

Insulin modulation of an endothelial nitric oxide component present in the alpha2- and beta-adrenergic responses in human forearm.

We explored in 51 normal subjects, distributed in various series of experiments, whether endothelium nitric oxide may play a role in insulin modulation of alpha2- and beta-adrenergic- evoked vascular responses. In particular, we examined the forearm blood flow response (FBF, ml.min-1.dl-1) to intrabrachial infusion of BHT-933 (0.5, 1, and 2 microg.min-1.dl-1) or isoproterenol (1, 3, and 6 ng. min-1.dl-1) in control conditions, during intrabrachial infusion of insulin alone (0.05 mU.kg-1.min-1) and associated with l-N-monomethylarginine (L-NMMA) (0.05 microg.min-1.dl-1), a nitric oxide synthase inhibitor. In control conditions both BHT-933 and isoproterenol induced a dose-dependent vascular response. Local hyperinsulinemia (deep venous plasma insulin 68.5+/-4 microU/ml) did not change basal FBF whereas attenuated BHT-933 vasoconstriction and enhanced isoproterenol vasodilation. L-NMMA reduced basal FBF and abolished the insulin effect on BHT-933 and isoproterenol response. To clarify whether a nitric oxide component is included in alpha2- and beta-adrenergic response and may be responsible for insulin vascular effect, we further examined BHT-933 and isoproterenol responses during nitric oxide inhibition. Interestingly, L-NMMA potentiated the BHT-933 vasoconstriction and attenuated the isoproterenol vasodilation and, in these conditions, insulin was no more able to exhibit its vascular effects. Finally, to rule out the possibility that the conteracting effect of L-NMMA may not be specifically related to insulin action, dose-response curves to phenylephrine (0.5, 1, and 2 microg.min-1.dl-1) or sodium nitroprusside (1, 2, and 4 microg.min-1.dl-1) were also performed. Both insulin and L-NMMA were unable to alter the phenylephrine-induced vasoconstriction and the sodium nitroprusside vasodilation. In conclusion, our data demonstrate an endothelial nitric oxide component in the alpha2- and beta-adrenergic vascular responses which is the target of the insulin vascular action.

Abnormal sympathetic overactivity evoked by insulin in the skeletal muscle of patients with essential hypertension.

The reason why hyperinsulinemia is associated with essential hypertension is not known. To test the hypothesis of a pathophysiologic link mediated by the sympathetic nervous system, we measured the changes in forearm norepinephrine release, by using the forearm perfusion technique in conjunction with the infusion of tritiated NE, in patients with essential hypertension and in normal subjects receiving insulin intravenously (1 mU/kg per min) while maintaining euglycemia. Hyperinsulinemia (50-60 microU/ml in the deep forearm vein) evoked a significant increase in forearm NE release in both groups of subjects. However, the response of hypertensives was threefold greater compared to that of normotensives (2.28 +/- 45 ng.liter-1.min-1 in hypertensives and 0.80 +/- 0.27 ng.liter-1 in normals; P less than 0.01). Forearm glucose uptake rose to 5.1 +/- .7 mg.liter-1.min-1 in response to insulin in hypertensives and to 7.9 +/- 1.3 mg.liter-1.min-1 in normotensives (P less than 0.05). To clarify whether insulin action was due to a direct effect on muscle NE metabolism, in another set of experiments insulin was infused locally into the brachial artery to expose only the forearm tissues to the same insulin levels as in the systemic studies. During local hyperinsulinemia, forearm NE release remained virtually unchanged both in hypertensive and in normal subjects. Furthermore, forearm glucose disposal was activated to a similar extent in both groups (5.0 +/- 0.6 and 5.2 +/- 1.1 mg.liter-1.min-1 in hypertensives and in normals, respectively). These data demonstrate that: (a) insulin evokes an abnormal muscle sympathetic overactivity in essential hypertension which is mediated by mechanisms involving the central nervous system; and (b) insulin resistance associated with hypertension is demonstrable in the skeletal muscle tissue only with systemic insulin administration which produces muscle sympathetic overactivity. The data fit the hypothesis that the sympathetic system mediates the pathophysiologic link between hyperinsulinemia and essential hypertension.

Association and cosegregation of stroke with impaired endothelium-dependent vasorelaxation in stroke prone, spontaneously hypertensive rats.

While hypertension is a major risk factor for stroke, it is not its sole determinant. Despite similar blood pressures, spontaneously hypertensive rats (SHR) do not share the predisposition to cerebrovascular disease typical of stroke-prone spontaneously hypertensive rats (SHRSP). We investigated vascular function in male SHR and SHRSP as well as in SHRSP/SHR-F2 hybrid animals. Animals were maintained on the appropriate dietary regimen necessary for the manifestation of stroke. Among the hybrid animals, a group of stroke-prone and a group of stroke-resistant rats were selected. Blood pressure was similar in all groups. Endothelium-independent vascular reactivity tested on isolated rings of thoracic aorta and basilar artery after death showed similar contractile and dilatory responses to serotonin and nitroglycerin, respectively, in all groups. In contrast, endothelium-dependent relaxation, in response to acetylcholine or substance P, was markedly reduced in SHRSP compared with SHR. Similarly, reduced vasodilatory responses were present in aortae of F2 rats that had suffered a stroke when compared with SHR or F2 rats resistant to stroke. The observed association and cosegregation of stroke with significant and specific impairment of endothelium-dependent vasorelaxation among SHRSP and stroke-prone F2 hybrids, respectively, suggest a potential causal role of altered endothelium-dependent vascular relaxation in the pathogenesis of stroke.

Effect of diabetes and metabolic syndrome on myocardial mechano-energetic efficiency in hypertensive patients. The Campania Salute Network.

Reduced myocardial mechano-energetic efficiency (MEE), estimated as stroke volume/heart rate ratio per g of left ventricular (LV) mass (LVM), and expressed in µl s-1 g-1 (MEEi), is a strong predictor of cardiovascular (CV) events, independently of LV hypertrophy and other confounders, including type II diabetes (DM). Decreased MEEi is more frequent in patients with diabetes. In the present analysis we evaluated the interrelation among MEEi, DM and metabolic syndrome (MetS) in the setting of arterial hypertension. Hypertensive patients from the Campania Salute Network, free of prevalent CV disease and with ejection fraction >50% (n=12 503), were analysed. Coexistence of MetS and DM was ordinally categorized into 4 groups: 8235 patients with neither MetS nor DM (MetS-/DM-); 502 without MetS and with DM (MetS-/DM+); 3045 with MetS and without DM (MetS+/DM-); and 721 with MetS and DM (MetS+/DM+). After controlling for sex, systolic blood pressure, body mass index, relative wall thickness (RWT), antihypertensive medications and type of antidiabetic therapy, MEEi was 333 µl s-1 g-1 in MetS-/DM-, 328 in MetS-/DM+, 326 in MetS+/DM- and 319 in MetS+/DM+ (P for trend <0.0001). In pairwise comparisons (Sidak-adjusted), all conditions, except MetS-/DM+, were significantly different from MetS-/DM- (all P<0.02). No statistical difference was detected between MetS-/DM+ and MetS+/DM-. Both MetS and DM are associated with decreased MEEi in hypertensive patients, independently to each other, but the reduction is statistically less evident for MetS-/DM+. MetS+/DM+ patients have the lowest levels of MEEi, consistent with the alterations of energy supply associated with the combination of insulin resistance with insulin deficiency.

Rays Sting: The Acute Cellular Effects of Ionizing Radiation Exposure.

High-precision radiation therapy is a clinical approach that uses the targeted delivery of ionizing radiation, and the subsequent formation of reactive oxygen species (ROS) in high proliferative, radiation sensitive cancers. In particular, in thoracic cancer ratdiation treatments, can not avoid a certain amount of cardiac toxicity. Given the low proliferative rate of cardiac myocytes, research has looked at the effect of radiation on endothelial cells and consequent coronary heart disease as the mechanism of ratdiation induced cardiotoxicity. In fact, little is known concerning the direct effect of radiation on mitochondria dynamis in cardiomyocyte. The main effect of ionizing radiation is the production of ROS and recent works have uncovered that they directly participates to pivotal cell function like mitochondrial quality control. In particular ROS seems to act as check point within the cell to promote either mitochondrial biogenesis and survival or mitochondrial damage and apoptosis. Thus, it appears evident that the functional state of the cell, as well as the expression patterns of molecules involved in mitochondrial metabolism may differently modulate mitochondrial fate in response to radiation induced ROS responses. Different molecules have been described to localize to mitochondria and regulate ROS production in response to stress, in particular GRK2. In this review we will discuss the evidences on the cardiac toxicity induced by X ray radiation on cardiomyocytes with emphasis on the role played by mitochondria dynamism.