C. Alessandri

Simvastatin inhibits the monocyte expression of proinflammatory cytokines in patients with hypercholesterolemia.

OBJECTIVE The purpose of this study was to assess if simvastatin has an anti-inflammatory activity in patients with hypercholesterolemia. BACKGROUND Simvastatin, an inhibitor of 3-hydroxy-methyl-glutaryl coenzyme A (HMG-CoA) reductase, reduced cardiovascular events in patients with myocardial infarction and hypercholesterolemia. METHODS Sixteen patients with polygenic hypercholesterolemia were randomly allocated to diet (n = 8) or diet plus 20 mg/day simvastatin (n = 8) for eight weeks. Before and at the end of treatment period, lipid profile and monocyte expression of tumor necrosis factor-alpha (TNF) and interleukin-1beta (IL-1beta) were measured. RESULTS At baseline no difference in lipid profile and monocyte expression of TNF and IL-1beta were observed between the two groups. In patients allocated to diet alone, no change in lipid profile and monocyte expression of TNF and IL-1beta was seen. In patients with diet plus simvastatin, significant decreases of total cholesterol (-27%, p<0.02), low density lipoprotein-cholesterol (-33%, p<0.02), and monocyte expression of TNF (-49%, p<0.02) and IL-1beta (-35%, p<0.02) were observed. At the end of treatment period, patients treated with simvastatin had lower cholesterol and monocyte TNF and IL-1beta than did patients assigned to diet alone. CONCLUSION This study suggests that simvastatin possesses anti-inflammatory activity via the inhibition of pro-inflammatory cytokines TNF and IL-1beta expressed by monocytes.

Non-alcoholic fatty liver syndrome: A hepatic consequence of common metabolic diseases

Background and Aims: The association of liver steatosis with a number of common metabolic conditions has been suggested. The aim of the present study was to evaluate the clinical features of subjects with different severities of steatosis.

Association between low-grade disseminated intravascular coagulation and endotoxemia in patients with liver cirrhosis

BACKGROUND & AIMS Hyperfibrinolysis may complicate the clinical course of liver cirrhosis. The aim of this study was to evaluate if, in cirrhosis, hyperfibrinolysis is primary or secondary to intravascular clotting activation and if endotoxemia is associated with activation of clotting and/or the fibrinolytic system. METHODS Clotting, fibrinolytic indexes, and endotoxemia were studied in 41 cirrhotic patients and 20 healthy subjects. RESULTS Twenty-seven cirrhotic patients (66%) had high plasma levels of prothrombin fragment F1 + 2, a marker of thrombin generation. Nineteen patients had elevated values of D-dimer, a marker of fibrinolysis in vivo. All patients with high values of D-dimer also had high values of prothrombin fragment F1 + 2. Endotoxemia was elevated in patients with severe liver failure and significantly correlated to prothrombin fragment F1 + 2. Thirty patients were treated for 7 days either with standard therapy (n = 15) or with standard therapy plus nonabsorbable antibiotics (n = 15). Although standard therapy did not significantly change laboratory indexes, a significant reduction of endotoxemia, prothrombin fragment F1 + 2, and D-dimer was found in those patients who received the combined treatment. CONCLUSIONS This study shows that, in cirrhotic patients, hyperfibrinolysis is not a primary phenomenon but occurs as a consequence of clotting activation and that endotoxemia might play a pathophysiological role.

Serum metalloproteinase 9 levels in patients with coronary artery disease: a novel marker of inflammation.

Background The finding that expression of metalloproteinases (MMPs) is induced in atherosclerotic plaques prone to rupture suggests the possibility that patients with atherosclerotic diseases would show enhanced blood levels of MMPs and that MMPs might represent a potential inflammatory risk factor for atherosclerosis. Therefore, the present study was aimed at verifying whether MMPs may represent sensitive markers of inflammation in patients with coronary artery disease. Methods MMP-2, MMP-9, interleukin (IL)-6, C-reactive protein (CRP), and fibrinogen levels were measured in blood samples obtained from 66 cases with previous acute myocardial infarction and 66 control subjects similar for age, sex, and major atherosclerotic risk factors but without history or evidence of atherothrombotic diseases. Results Biohumoral markers of inflammation and MMP-9 levels were significantly elevated in cases compared with controls (median values 40.6 versus 9.8 ng/mL; p < .0001), whereas MMP-2 levels did not differ between the two groups (median values 839 versus 873 ng/mL; p = .53). A direct correlation was found among MMP-9, CRP, IL-6, and fibrinogen levels. Conditional logistic regression analysis showed that MMP-9 is related to myocardial infarction (p = .006) even after adjusting for cardiovascular medications and CRP. Conclusion These findings suggest that measurement of serum MMP-9 levels may represent a novel marker of inflammation in patients with known coronary artery disease and might provide an index of plaque activity in this clinical setting.

Inhibition of tissue-factor-mediated thrombin generation by simvastatin.

A previous study has shown that simvastatin reduces in vivo clotting activation and monocyte tissue factor (TF) expression. This effect, however, was only in part attributable to the reduction of serum cholesterol, suggesting that more than one mechanism may be involved. Furthermore, it was not investigated if the inhibition of clotting activation was dependent upon the reduced expression of monocyte TF. In order to assess if simvastatin directly affects clotting activation, we developed an in vitro method in which clotting system is activated by monocytes stimulated with LPS. Monocytes were prepared from blood taken from healthy volunteers or patients with hypercholesterolemia and incubated with heparinized plasma plus either simvastatin (0.01-10 microM) or medium as control. Samples were then stimulated with LPS (4 microg/ml) and after 6 h the rate of thrombin generation, assessed by prothrombin fragment (F) 1+2, was measured. In separate experiments, we measured the expression of TF by monocytes which were incubated with simvastatin and then stimulated with LPS. The study showed that compared to control, LPS-stimulated monocytes induced abundant formation of F1+2, which was inhibited by simvastatin in a dose-dependent manner. Simvastatin also inhibited dose dependently the monocyte expression of TF. This study suggests that simvastatin inhibits the rate of thrombin generation by directly interfering with the monocyte expression of TF.

Preparation and biodistribution of 99mtechnetium labelled oxidized LDL in man

Radiolabelled autologous low density lipoprotein (LDL) has previously been used to study in vivo distribution and metabolism of native-LDL. Non-invasive imaging of atherosclerotic lesions using 99mTc-LDL was shown to be feasible in animal models and patients but the clinical utility remains to be assessed. Since recent reports suggest that oxidized LDL may play a major role in the pathogenesis of atherosclerosis, we developed a technique to oxidize autologous LDL and compared the biodistribution of oxidized-LDL with that of native-LDL in man. In addition, we evaluated the uptake in vivo of oxidized- and native-LDL by atherosclerotic plaques. LDL, obtained from human plasma was treated with various combinations of copper ions and H2O2 to induce oxidative modification by increasing the content of lipid peroxidation products and electrophoretic mobility. When LDL (0.3 mg/ml) was incubated with 100 microM Cu2+ and 500 microM H2O2 oxidation occurred rapidly within 1 h, and was labelled with 99mTc efficiently as native LDL. In vivo distribution studies revealed a faster plasma clearance of oxidized-LDL compared to native-LDL, and a higher uptake by the reticuloendothelial system. Tomographic scintigraphy of the neck in patients suffering from transient ischemic attacks, revealed accumulation of radiolabelled LDL preparations in the carotid artery affected by atherosclerotic lesions. We developed a technique to rapidly oxidize LDL using copper and H2O2. Biodistribution data demonstrate that oxidized-LDL is rapidly cleared from circulation, is taken up mostly by organs rich in macrophages, and can be detected at the level of carotid plaques.

Simvastatin reduces monocyte-tissue-factor expression type IIa hypercholesterolaemia

Inhibitors of 3-hydroxy-methyl-glutaryl coenzyme A reductase have been shown to reduce cardiovascular events in patients with raised and average serum cholesterol. It is unclear whether this effect is attributable solely to reduction of serum cholesterol or to other mechanisms. We analysed whether simvastatin directly affects expression of monocyte tissue factor (TF). After 4 weeks of diet alone (fat intake <30% of total calories, cholesterol <300 mg daily, polyunsaturated/ saturated fatty acids ratio=1·0) (run-in phase), 24 patients (12 men and 12 women; mean age 52 [SD 8] range 35–70 years) with polygenic hypercholesterolaemia were randomised to simvastatin (20 mg daily) or to continue diet for 8 weeks. Before and after treatment, expression of TF antigen and activity as well as the circulating concentrations of prothrombin fragment F1+2, a marker of thrombin generation, were measured. Nine parts of blood were mixed in a pre-cooled vacutainer (Becton Dickinson Vacutainer System, France) with 1 part of 3·8% sodium citrate and centrifuged for 20 min at 2000 g at –4oC. Plasma samples for measurement of F1+2 (Enzygnost F1+2, Behringwerke ag, Marburg) were stored at –40oC. To measure monocyte TF, peripheral blood mononuclear cells were isolated from heparinised venous blood (2 10 cells/mL) and incubated for 6 h with 0·4 ng/mL lipopolysacchariae (Escherichia coli [OB11:B4, Sigma, St Louis, MI, USA). In the lysate of the cells, TF antigen was measured by an ELISA test (Imubind Tissue Factor ELISA kit, American Diagnostica Inc, Greenwich, CT) and TF activity was determined by measuring monocyte procoagulant activity with one stage clotting assay. Hypercholesterolaemic patients showed significantly higher concentrations of F1+2 (mean [SD] 2·2 [0·4] vs 0·6 [0·3] nmol/L: p<0·0001), TF antigen (median [range] 63 [41–89] vs 16 [10–39] pg/2 10 monocytes; p<0·0001) and activity (median [range] 31 [20–44] vs 9 [4–20] U/2 10 monocytes; p<0·0001) than 24 controls matched for age and sex (unpaired t test and Mann-Whitney U test). Patients randomised to diet or diet plus simvastatin had similar clinical (not shown) and laboratory variables (table). In patients continuing the follow-up by diet alone, no significant changes of the variables were observed. In patients taking simvastatin there was a significant decrease of cholesterol, LDL cholesterol, F1+2, and monocyte TF expression. Comparing the diet and simvastatin groups at the end of the treatment period, simvastatin group showed significantly lower concentrations of F1+2, TF antigen, and activity. This study shows that simvastatin reduces the expression of monocyte TF, an effect which may explain the reduction of cardiovascular events elicited by simvastatin.

Dipyridamole inhibits lipid peroxidation and scavenges oxygen radicals

Dipyridamole incubatedin vitro in systems which peroxidize fatty acids inhibited arachidonic acid, gammalinolenic acid and linoleic acid peroxidation. In the xanthine-xanthine-oxidase system, which produces superoxide anion, dipyridamole inhibited the reduction of cytochrome-C in a dose-dependent fashion. In systems generating hydroxyl radicals, dipyridamole reduced deoxyribose degradation in a dose-dependent manner. The study suggests that dipyridamole inhibits lipid peroxidation, probably by scavening oxygen free radicals.

Bleeding time does not predict gastrointestinal bleeding in patients with cirrhosis

BACKGROUND/AIMS Bleeding time, a laboratory test which explores primary hemostasis, may be prolonged in cirrhosis, but whether abnormal bleeding time identifies patients with cirrhosis who are at risk of bleeding has never been investigated. The aim of this study was to analyze the relationship between bleeding time and the risk of gastrointestinal bleeding. METHODS Eighty consecutive patients with liver cirrhosis (47 males, 33 females; age, 60 +/- 9 years; range 31 to 83 years) and esophageal varices were enrolled in the study. RESULTS In the whole series of patients bleeding time was 11 +/- 6 min; it increased as the degree of liver deficiency increased, from low to severe (p = 0.007). During 14 +/- 9 (median (range): 12 (1-34) months of follow-up, 28 (35%) patients experienced gastrointestinal bleeding. They had a longer bleeding time, higher incidence of previous bleeding, more severe liver failure and larger variceal size than patients who did not bleed. However, multivariate analysis (Coxs model) showed that only previous bleeding, liver failure and variceal size were independently associated with bleeding. Similar data were obtained in patients with moderate-severe liver insufficiency (B and C degree according to Child-Pughs classification). In patients who had never bled (n = 54), the severity of liver failure and variceal size were independent predictors of bleeding. CONCLUSIONS This study shows that bleeding time is not a predictor of gastrointestinal bleeding in patients with cirrhosis.

Lipoprotein(a) serum levels in patients affected by chronic obstructive pulmonary disease

A recent study has suggested that symptoms of chronic bronchitis predict the risk of coronary disease independently of the known major cardiovascular risk factors. High serum levels of lipoprotein(a) (Lp(a)) have also been considered as an independent risk factor for coronary heart disease. Therefore, the aim of the present study was to investigate the behaviour of Lp(a) in patients affected by chronic obstructive pulmonary disease (COPD). Serum levels of total-cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglycerides, apolipoprotein (Apo) B-100, and Lp(a) were measured in 90 COPD patients and in 90 normal subjects matched for age, sex and smoking habit. COPD patients showed lower serum levels of Apo B-100 (P<0.0001) and Lp(a) (P<0.003) compared to controls. Conversely, TC, HDL-C, LDL-C and triglycerides were similar between patients and controls. No significant differences were found in Apo B-100 and Lp(a) levels of patients either undergoing different therapeutic regimens, or with different smoking habits. A significant correlation between Apo B-100 and Lp(a) (rho=0.433, P<0. 0001) was also observed. In conclusion, COPD patients do not show an atherogenetic lipid pattern and their increased risk of coronary disease could be attributable to different factors, such as the ongoing hypercoagulability state often associated with COPD.