Mediterranean, but not lacto-ovo-vegetarian, diet positively influence circulating progenitor cells for cardiovascular prevention: The CARDIVEG study.

AIM: To evaluate the possible association between dietary habits and progenitor cells using data obtained from a randomized crossover trial using two different diets, lacto-ovo-vegetarian (VD) and Mediterranean (MD), the CARDIVEG study. METHODS AND RESULTS: Eighty clinically healthy subjects with a low-to-moderate cardiovascular risk profile (61 F; 19 M; mean age: 50.7 ± 11.6 years) were randomly assigned to isocaloric VD and MD diets lasting three months each, and then crossed. The two diets showed no effects on endothelial progenitor cells and circulating endothelial cells but opposite effects on circulating progenitor cells. In fact, VD determined significant (p < 0.05) and negative changes on circulating progenitor cells, with an average geometric variation of -130 cells/106 events for CD34+/CD45-/dim, -80 cells/106 events for CD133+/CD45-/dim, and -84 cells/106 events for CD34+/CD133+/CD45-/dim while MD determined significant (p < 0.05) and positive changes for CD34+/CD45-/dim levels, with a geometric mean increase of +54 cells/106 events. No significant correlations were observed between changes in progenitor cells and changes in inflammatory parameters during the VD phase. On the other hand, during the MD phase negative correlations between changes of CD34+/CD45-/dim and interleukin-6 (R = -0.324; p = 0.004) as well as interleukin-8 (R = -0.228; p = 0.04) and monocyte chemotactic protein-1 (R = -0.277; p = 0.01), were observed. These correlations remained significant also after adjustment for confounding factors only for CD34+/CD45-/dim and interleukin-6 (ß = -0.282; p = 0.018) and monocyte chemotactic protein-1 (ß = -0.254; p = 0.031). CONCLUSIONS: MD, but not VD, reported a significant and positive effect on circulating progenitor cells in a group of subjects at low-to-moderate cardiovascular risk, probably acting through the modulation of inflammatory parameters.

Cardiovascular and thrombophilic risk factors for idiopathic sudden sensorineural hearing loss.

BACKGROUND: In recent years there has been a significant increase in the diagnosis of sudden sensorineural hearing loss (SSHL) in western, countries with an incidence of 20 of 100,000 people affected every year. No clear causes for this disease have been found thus far, but cochlear ischemia has been hypothesized in patients in whom an infectious episode or acoustic neurinoma have been excluded. OBJECTIVES: The aim of this case-control study was to investigate a number of acquired and inherited thrombophilic risk factors [antithrombin, protein C and S; factor V (FV) Leiden, FII polymorphism; lupus anticoagulant (LA); anticardiolipin (aCL) antibodies; fasting homocysteine (Hcy); lipoprotein(a) (Lp(a)); plasminogen activator inhibitor-1 (PAI-1)] in addition to cardiovascular risk factors in patients with idiopathic SSHL (ISSHL). PATIENTS AND METHODS: We investigated 155 patients (67 male/88 female; age: 55 (range 19-79 years) with a diagnosis of ISSHL within 30 days from the onset of symptoms, and 155 controls (67 male/88 female; age 54 (range 19-78 years). Fasting Hcy levels were significantly higher in patients than in controls [11.6 (6.7-60) micromol/L vs. 8.7 (5.0-24) micromol/L] as well as PAI-1 levels [19 (2-95) mg/dL vs. 14.5 (4.0-87) mg/dL]. Lupus anticoagulant was present in 13 of 155 (8.4%) patients; 20 patients (12.9%) had positivity of aCL (four IgM and 16 IgG). In no patient was a deficiency of physiological clotting inhibitors antithrombin, protein C and protein S found. No significant differences between patients and controls were observed for Lp(a) plasma levels [111 (1-1146) mg/L vs. 103 (11-695) mg/L] and for the presence of FV Leiden (4.5% vs. 4.5%) and FII variant G20210A (3.8% vs. 3.2%). RESULTS AND CONCLUSIONS: Independent risk factors for ISSHL at the multivariate analysis (adjusted for age, sex and the traditional cardiovascular risk factors) were the positivity of aCL: OR 5.6 (95% CI 2.0-15.3); cholesterol levels within the second and third tertiles (with respect to the first tertile): T2 = OR 4.8 (95% CI 1.9-12.6)/T3 = OR 19 (95% CI 7-50.1); PAI-1 and Hcy levels within the third tertile (with respect to the first tertile): OR 20 (95% CI 7.8-78) and OR 4.0 (95% CI 2.0-8.1), respectively. These preliminary data suggest that hypercholesterolemia, hyperhomocysteinemia, elevated PAI-1 levels and anticardiolipin antibodies are associated with ISSHL, so indirectly supporting the hypothesis of a vascular occlusion in the pathogenesis of the disease.

Pharmacologic data reveal the heterogeneity of angiotensin-converting enzyme according to its source (lung versus heart).

Angiotensin-converting enzyme (ACE) has 2 different active sites: a C-site (in the carboxy terminal region) and an N-site (in the amino terminal part). Some ACE inhibitors have a relatively greater affinity for the C-sites, whereas others bind to the 2 sites with equal affinity. The different ontogenesis of lung and heart endothelial cells can be related to binding differences to the C- and N-sites. We labeled Ro31-8472, a clizapril derivative, which has the same affinity for the 2 ACE sites. Binding of 125I-Ro31-8472 to human left ventricle and lung plasma membranes was saturable, inhibited by ethylene diaminetetraacetic acid and displayed affinities of 360 +/- 41 pM in heart and 320 +/- 51 pM in lung. For captopril the Hill slope was 0.57 +/- 0.03 for heart and 0.48 +/- 0.05 for lung; for delaprilat, a nonsulfhydryl analogue of captopril, the slope was 0.43 +/- 0.05 for heart and 0.55 +/- 0.05 for lung. These drugs were characterized by biphasic competition isotherms. The Hill slope of enalaprilat was 1.01 +/- 0.06 for heart and 0.93 +/- 0.06 for lung, and Ro31-8472 had a slope of 0.97 +/- 0.04 for heart and 0.93 +/- 0.03 for lung. The affinity of ACE inhibitors with Hill slope different from unity varied according to the source of ACE; in fact, delaprilat had greater affinity for the high-affinity sites of heart than lung (pKi, 9.89 and 9.47, respectively), whereas captopril had greater affinity for the high-affinity sites of lung than heart (9.40 and 8.85, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of fluvastatin on lipids and fibrinolysis in coronary artery disease.

This randomized, double-blind, placebo-controlled study shows that 20-week fluvastatin treatment induces beneficial changes in the lipid panel and a shift in the fibrinolytic pathway toward activation through a decrease in tissue plasminogen activator antigen. Fluvastatin treatment causes no variation in lipoprotein(a) circulating levels.

Activated protein C resistance is a risk factor for central retinal vein occlusion.

Central retinal vein occlusion is one of the most common retinal vascular disorders. Few and contrasting data are available on the prevalence of hemostatic risk factors in patients with central retinal vein occlusion. The aim of this study was to investigate the most common hemostasis-related inherited risk factors for venous thrombosis in a group of 53 central retinal vein occlusion patients (median age 59 years, range 18-77 years) and in 53 comparable control subjects (median age 57 years, range 22-84 years). No difference was found in antithrombin III, protein C and protein S plasma levels between patients and controls. At univariate analysis, activated protein C resistance (odds ratio 5.8) and factor V Leiden (odds ratio 4.4) were significantly associated with central retinal vein occlusion whereas G20210A polymorphism of the prothrombin gene was not. After adjustment for sex, age, and the other classic vascular risk factors (hypertension, diabetes, hypercholesterolemia, smoking) activated protein C resistance remained the only independent risk factor for central retinal vein occlusion (odds ratio 11.5). These data indicate that activated protein C resistance may play a role in the pathophysiology of central retinal vein occlusion.

Lower homocysteine levels in renal transplant recipients treated with everolimus: a possible link with a decreased cardiovascular risk?

Cardiovascular disease (CVD) is the main cause of morbidity and mortality in renal transplant recipients. The incidence of CVD in this setting is approximately 5-fold greater than in age- and and gender-matched subjects. This excess cardiovascular risk is not completely explained by traditional cardiac risk factors. It has been well documented that these patients show greatly increased prevalence of both fasting and postmethionine-loading hyperhomocysteinemia (hHcy) compared with the general population. An immunosuppressive therapy based on everolimus has been demonstrated to reduce the incidence major adverse coronary events at 4 years compared with azathioprine among heart transplant recipients. In contrast, scarce data are available on the impact of everolimus on emerging risk factors, such as homocysteine (Hcy), in renal transplant recipients. The aim of this study was to evaluate the possible impact of everolimus compared with other immunosuppressive regimes among 132 stable recipients, including 91 men and 41 women who were at least 1 year after transplant with stable renal function and no clinical evidence of acute or chronic renal graft rejections. We compared 31 subjects on everolimus immunosuppressive therapy (group A) versus 101 on immunosuppressive therapy based on cyclosporine, steroids, and mycophenolate. The Hcy levels were significantly lower among group A patients compared with group B: 16.5 +/- 5 micromol/L vs 21.2 +/- 11 micromol/L; P < .005. Hyper-Hcy, defined as Hcy levels >15 micromol/L, was diagnosed in 18 out of 31 patients (51%) of group A and in 82 out of 101 patients (81%) of group B. This preliminary study demonstrates a favorable impact of everolimus on a marker of atherothrombosis which is associated with a worse vascular prognosis.

Affinity of angiotensin I-converting enzyme (ACE) inhibitors for N- and C-binding sites of human ACE is different in heart, lung, arteries, and veins.

Angiotensin-converting enzyme (ACE) has two enzymatically active domains: a C-domain in the carboxy terminal region and an N-domain in the amino terminal region. We based the pharmacologic characterization of these sites on the rat testis-lung model. In testis, only a truncate form of ACE is present (C-site), whereas both N- and C-sites are present in lung. In this model, captopril was shown to be N-selective and delaprilat to be C-selective. Ro 31-8472, a cilazapril derivative, and enalaprilat proved to be not site selective. We used these drugs to evaluate the affinity of C and N sites in various human tissues involved in the cardiovascular actions of ACE and used [125I]Ro31-8472 as ligand. The number and affinity of ACE binding sites were 17,680 +/- 2,345 fmol/mg protein (Kd = 0.32 +/- 0.04 nM) in lung, 560 +/- 65 (Kd = 0.36 +/- 0.05 nM) in heart, 237 +/- 51 (Kd = 0.37 +/- 0.06 nM) in coronary artery, 236 +/- 63 (Kd = 0.14 +/- 0.05 nM) in saphenous vein, and 603 +/- 121 (Kd = 0.50 +/- 0.06 nM) in mammary artery. The affinity (pKi) of captopril for the N sites ranged from 9.40 +/- 0.14 (lung) to 8.41 +/- 0.10 (coronary artery). The affinity for the C-site by delaprilat ranged from 9.97 +/- 0.15 (coronary artery) to 9.10 +/- 0.14 (mammary artery). Therefore, the affinity of C- and N-sites of ACE for ACE inhibitor (ACEI) drugs is different according to the organ involved. Because ACE is a glycosylated enzyme and glycosylation is organ dependent, we suggest that organ-specific glycosylation affects the binding characteristics of ACE inhibitors to N- or C-site of human tissular ACE.

Tissue factor and tissue factor pathway inhibitor levels in unstable angina patients during short-term low-molecular-weight heparin administration.

High tissue factor (TF), tissue factor pathway inhibitor (TFPI) levels and a hypercoagulability state have been documented in unstable angina patients. We evaluated whether short-term enoxaparin administration (100 IU/kg b.i.d. for 3 d) reduces the high TF levels and the hypercoagulability state, and whether it influences the fibrinolytic system in 20 unstable angina patients. On d 3, we observed a significant reduction in TF levels both 1 h and 4 h after the morning injection (-25.6% and -21.7%; P < 0.001 respectively) in comparison with the base-line levels. Both 1 and 4 h after the morning injection on the d 3, TFPI levels significantly (P < 0.001) increased (+96.4%, +96.9% respectively) with respect to the base-line values. After enoxaparin administration, at all observation times, thrombin-antithrombin complexes and prothrombin fragment F1 + 2 levels were significantly (P < 0.001) lower with respect to base-line levels. We observed a slight but significant increase in tissue plasminogen activator antigen levels in preinjection samples, as well as 1 h and 4 h after enoxaparin administration, in comparison with the base-line values. This study provides evidence that low-molecular-weight heparin (LMWH) administration, in addition to a reduction of hypercoagulability and a mild fibrinolytic activation, is associated with decreased TF levels, so indicating a novel mechanism of interference of LMWH with the haemostatic system.

Atrial natriuretic peptide in multiple system atrophy.

Central nervous system feedback loops centered on hypothalamic neurons control atrial natriuretic peptide (ANP). We evaluated the ANP response to arterial hypotension, isotonic blood volume expansion, and increase in plasma osmolality in 14 patients with multiple system atrophy (MSA). Seven of the patients were characterized by a lack of vasopressin response to hypotension (MSA type B), suggesting chronic sinoaortic denervation, and seven by a preserved response (MSA type A). Orthostatic hypotension decreased ANP in controls and type A patients, whereas ANP in type B was not affected. Isotonic saline infusion increased ANP and diuresis in controls and type A patients, whereas it did not affect ANP in type B. Osmotic load increased plasma osmolality and vasopressin in controls and MSA patients and ANP in controls and type A but not in type B patients. In MSA patients with altered afferent control of vasopressin, ANP secretion is not stimulated by blood volume expansion, osmotic load, or blood pressure, suggesting that afferent excitatory control plays a role in the release of ANP.

High prevalence of mild hyperhomocysteinemia in patients with abdominal aortic aneurysm.

PURPOSE: In vitro studies have recently demonstrated that homocysteine interacts with the aortic wall by inducing both elastolysis and endothelial perturbation. The aim of this study was to evaluate homocysteine plasma levels and their relationships with aortic diameter and endothelial damage in patients with abdominal aortic aneurysm. SUBJECTS AND METHODS: Fifty-eight consecutive male patients (mean age, 69.5 +/- 6.6 years; age range, 49-78 years) who underwent abdominal aortic aneurysm surgery were enrolled in the study. Twenty-two of 58 patients had no clinical or instrumental evidence of atherosclerosis. Sixty control subjects were age matched and sex matched with the patients. In all of the subjects, we evaluated total homocysteine and thrombomodulin plasma levels and the distribution of the C677T methylenetetrahydrofolate reductase gene mutation. RESULTS: Hyperhomocysteinemia was found in 26 (48%) of the 58 patients with abdominal aortic aneurysm, and homocysteine plasma levels were significantly higher in patients than in control subjects (15.7 +/- 6.5 micromol/L vs 9.6 +/- 3.9 micromol/L; P <. 0001). In addition, the subgroup of patients with abdominal aortic aneurysm who did not show evidence of atherosclerosis showed homocysteine plasma levels significantly higher than those in the controls (14.8 +/- 6.1 micromol/L vs 9.6 +/- 3.9 micromol/L; P <. 001). A larger aneurysmal size was detected in hyperhomocysteinemic patients than in those with normal homocysteine plasma levels (5.09 +/- 0.84 cm vs 5.79 +/- 1.5 cm; P <.05). The genotype distribution of the C677T methylenetetrahydrofolate reductase mutation was as follows: TT 21%, TC 55%, and CC 24% in the patients; TT 10%, TC 58%, and CC 32% in the controls. Moreover, in patients a significant correlation (P <.005) between homocysteine plasma level and 677TT methylenetetrahydrofolate reductase genotype was found. Thrombomodulin plasma levels were significantly higher (P <.00005) in patients (median, 30 ng/mL; range, 10-164 ng/mL) than in controls (median, 19 ng/mL; range, 13-44 ng/mL), and thrombomodulin levels were significantly higher (P <.005) in hyperhomocysteinemic patients (median, 39.5 ng/mL; range, 15-164 ng/mL) than in normohomocysteinemic patients (median, 27.5 ng/mL; range, 10-85 ng/mL). In addition, in patients with abdominal aortic aneurysm, a direct significant correlation (P <.005) was found between homocysteine and thrombomodulin. CONCLUSIONS: These data indicate an association between the presence of AAA in patients selected for surgical treatment of AAA and elevated homocysteine plasma levels and suggest that homocysteine may induce endothelial perturbation and stimulation in these patients.

Risk factors for cardiovascular disease in renal transplant recipients: new insights.

Long-term survival of renal transplant recipients appears to be influenced by the occurrence of thromboembolic complications and cardiovascular disease. In order to investigate the prevalence of new hemostasis-related risk factors for venous and arterial thrombosis, we investigated 63 renal transplant recipients and 66 age- and sex-matched control subjects. We assayed antiphospholipid antibodies [lupus anticoagulant (LA) and anticardiolipin antibodies (aCL)], lipoprotein (a) [Lp(a)], plasminogen activator inhibitor-1 (PAI-1), and total homocysteine (tHcy) levels. We found a significantly higher prevalence of positivity for LA (P < 0.001); no difference was detected in the prevalence of aCL between patients and controls. PAI-1 levels were significantly higher in renal transplant recipients than in controls [12.3 IU/ml (2-45.5) vs 7.9 IU/ml (4-18.0); P < 0.0001] with an odd ratio (OR) of 11.8 (4.9-28.5) in univariate analysis and of 5.8 (2.1-15.4) in multivariate analysis. Lp(a) levels were higher in patients then in controls [159 mg/l (1-992) vs 100.5 mg/l (10-412); P < 0.005] with an OR of 5.9 (1.9-18.4) in univariate analysis and of 3.5 (0.9-13.4) in multivariate analysis. Fasting levels of tHcy were significantly higher in renal transplant recipients [7.0 micromol/l (4.0-68) vs 8.1 micromol/l (2.0-24.0); P < 0.00001] with an OR of 40.4 (14.7-111) in univariate analysis and of 33.1 (11.1-115.5) in multivariate analysis. After methionine loading test, we documented levels of tHcy above the 90th percentile of controls in 60/63 patients (95%). Finally, we found a significant correlation between tHcy and PAI-1 plasma levels (r = 0.76; P < 0.000001). Our results show a high prevalence of hemostasis-related risk factors for arterial and venous thrombosis in renal transplant recipients, suggesting the need for the investigation of these patients for the presence of these risk factors in order to improve their long-term survival and to tailor therapy.