Ezetimibe reduces cholesterol content and NF-kappaB activation in liver but not in intestinal tissue in guinea pigs.

BACKGROUND: Statins (HMG CoA reductase inhibitors), in addition to reducing circulating cholesterol and incidence of coronary heart disease, also have pleiotropic, anti-inflammatory effects. Patients with chronic liver diseases, non-alcoholic fatty liver disease (NAFLD) or hepatitis C are often excluded from statin therapy because of adverse effects in a small cohort of patients despite increased cardiovascular risk cholesterol. Ezetimibe, which inhibits cholesterol absorption by inhibition of Niemann-Pick C1 like 1 (NPC1L1) protein in the brush border of intestinal cells, has been suggested as a new therapeutic option in these patients. METHODS: Effects of ezetimibe on lipoprotein metabolism, hepatic and intestinal lipid content in guinea pigs, an animal model with a lipoprotein profile and pattern similar to humans were investigated. In order to investigate a possible effect of ezetimibe on cholesterol induced inflammation NF-kappaB activation as an indicator for inflammatory processes in liver and gut tissue was measured. RESULTS: Lipid enriched diet led to accumulation of lipids in hepatic tissue which caused strong hepatic NF-kappaB activation. Ezetimibe reduced lipid diet induced increase of circulating cholesterol by about 77% and prevent hepatic NF-kappaB activation almost completely. In contrast in intestinal cells Ezetimibe, though lowering diet induced cholesterol accumulation, increased triglyceride content and subsequent NF-kappaB activation. CONCLUSION: In summary these data show, that ezetimibe effectively reduced diet induced circulating cholesterol levels, hepatic lipid accumulation and inflammatory response in our guinea pig model. However this drug elicited a local inflammatory response in intestinal tissue. Whether these diverse effects of ezetimibe on inflammatory parameters such as NF-kappaB have clinical relevance remains to be determined.

Cholesterol rather than procalcitonin or C-reactive protein predicts mortality in patients with infection.

Serum cholesterol procalcitonin (PCT) and C-reactive protein (CRP) levels were measured consecutively in 76 critically ill patients at admission to the intensive care unit. The presence of infection was defined according to the CDC (Centers for Disease Control and Prevention) criteria; in-house mortality, underlying diseases, and severity of sepsis were monitored. Nonsurvivors had significantly lower cholesterol levels compared with survivors (69 mg/dL [range, 37-88 mg/dL] vs. 96 mg/dL [range, 71-132 mg/dL], P = 0.006) whereas no significant differences were noted for serum PCT and CRP levels. In a cohort of patients with cholesterol levels of 50 mg/dL or less, 82% did not survive as compared with patients with cholesterol levels of 100 mg/dL or greater (mortality, 21%). In a control group without infection, no difference of cholesterol, PCT, or CRP was found between survivors and nonsurvivors. Our data show that low cholesterol levels in patients with infectious disease have a prognostic value and may be useful markers to identify high-risk patients already at admission.

oxLDL uptake by dendritic cells induces upregulation of scavenger-receptors, maturation and differentiation.

BACKGROUND: Several studies have proposed a pathogenic role for oxidized LDL (oxLDL) in atherosclerosis. We tested the hypothesis whether oxLDL modulates dendritic cells (DCs), since these important antigen-presenting cells have been implicated in atherogenesis. We investigated the uptake of oxLDL by DCs, the scavenger-receptors involved and the resulting changes in phenotype and cytokine-spectra. In addition, we analyzed the impact of oxLDL on the nuclear transcription factor-kappa B (NF-kappaB)-pathway. METHODS AND RESULTS: oxLDL (10microg/ml) increased the expression of the scavenger-receptors CD205 and CD36 and decreased the mannose-receptor expression. The lectin-like oxLDL-receptor (LOX-1)-expression was not affected. The endocytotic capacity of dextran and lucifer-yellow was moderately decreased by oxLDL. Blockage of the scavenger-receptors CD36, LOX-1 and CD205 reduced oxLDL uptake. Furthermore, oxLDL induced DC-maturation and triggered differentiation of DCs in myeloid and plasmacytoid DCs. oxLDL decreased IL-10 secretion and increased IL-6 release. Finally, oxLDL induced an activation of the NF-kappaB-pathway. Inhibition of IkappaBalpha-phosphorylation diminished the oxLDL-induced DC-maturation and -differentiation. CONCLUSION: oxLDL uptake by DCs is mediated by the scavenger-receptors LOX-1, CD36, and CD205. oxLDL induces a proinflammatory cytokine profile in human DCs leading to DC-maturation and -differentiation which can, in part, be explained by an activation of the NF-kappaB-pathway. These results support the hypothesis that vascular inflammation may be aggravated by oxLDL induced DC-activation.

Simvastatin reduces endotoxin-induced nuclear factor kappaB activation and mortality in guinea pigs despite lowering circulating low-density lipoprotein cholesterol.

Statins, which are effective lipid-lowering drugs, also possess anti-inflammatory potential. However, circulating lipoproteins may also play a protective role during acute inflammatory diseases because of their ability to bind bacterial toxins. Low cholesterol levels have been reported in inflammatory conditions, and plasma cholesterol concentrations inversely correlate with severity and clinical outcome in septic patients. It is thus paradoxical that statins, which drastically reduce circulating cholesterol levels, should be beneficial in patients with inflammatory disease who are already hypocholesterolemic. We investigated the effect of simvastatin on LPS-induced nuclear factor kappaB (NF-kappaB) activation, TNF release, and mortality in guinea pigs, an animal model with a lipoprotein profile and pattern similar to humans. In the present study, simvastatin reduced circulating total and low-density lipoprotein cholesterol levels by 68% and 76%, respectively, and LPS-induced mortality from 73% to 20%. This reduction was accompanied by a significant reduction of NF-kappaB activation in the liver tissue, splenocytes, and plasma TNF levels by about 80%, 50%, and 77%, respectively. Our data suggest that simvastatin, despite lowering circulating low-density lipoprotein cholesterol, decreased LPS toxicity by reduction of NF-kappaB activation and subsequent release of TNF by modulating 3-hydroxy-3-methylglutaryl coenzyme A reductase activity and therefore deserves consideration as a possible adjuvant therapy in acute inflammatory disease.

Chemoembolization combined with pravastatin improves survival in patients with hepatocellular carcinoma.

BACKGROUND/AIMS: Pravastatin, a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, has been shown to inhibit growth and to induce apoptosis in human hepatocellular carcinoma (HCC) cells. However, the potential benefit of pravastatin in HCC patients has still not been characterized, which prompted us to test the efficacy of pravastatin in patients with advanced HCC. METHODS: We investigated prospectively a cohort of 183 HCC patients who had been selected for palliative treatment by transarterial chemoembolization (TACE). Fifty-two patients received TACE combined with pravastatin (20-40 mg/day) and 131 patients received chemoembolization alone. Six independent predictors of survival according to the Vienna survival model for HCC were equally distributed in both groups. RESULTS: During the observation period of up to 5 years, 31 (23.7%) out of 131 patients treated by TACE alone and 19 (36.5%) out of 52 patients treated by TACE and pravastatin survived. Median survival was significantly longer in HCC patients treated by TACE and pravastatin (20.9 months, 95% CI 15.5-26.3, p = 0.003) than in HCC patients treated by TACE alone (12.0 months, 95% CI 10.3-13.7). CONCLUSION: Combined treatment of chemoembolization and pravastatin improves survival of patients with advanced HCC in comparison to patients receiving chemoembolization alone.

Heparin-mediated extracorporeal low density lipoprotein precipitation as a possible therapeutic approach in preeclampsia.

Preeclampsia is a pregnancy-related hypertensive disease resulting in substantial maternal and neonatal morbidity and mortality. Until today there is no satisfactory treatment to stop disease progression except immediate delivery of the fetus. Heparin-mediated extracorporeal low density lipoprotein (LDL) precipitation (H.E.L.P.) apheresis removes simultaneously circulating LDL, lipoprotein(a) [Lp(a)], fibrinogen, C-reactive protein (CRP) and various proinflammatory and procoagulatory factors. This study was to test the feasibility of H.E.L.P. apheresis in preeclamptic patients and its potential effects on blood and placental markers of preeclampsia. We applied H.E.L.P. apheresis to nine preeclamptic patients and it was well tolerated. Their gestational ages could be continued by 17.7 (3-49) more days. Eight of the nine neonates did well during their neonatal stage. One infant died of late-onset sepsis. H.E.L.P. apheresis reduced significantly circulating levels of triglycerides, total and LDL-cholesterol, Lp(a), fibrinogen, hs-CRP, TNFalpha, sVCAM-1, E-selectin, lipopolysaccharide binding protein (LBP), homocysteine and plasma viscosity. We conclude that H.E.L.P. apheresis reduced maternal circulating levels of proinflammatory and coagulatory markers and plasma viscosity without overt maternal or neonatal clinical side effects.

Prognostic value of interleukin 6, procalcitonin, and C-reactive protein levels in intensive care unit patients during first increase of fever.

To investigate the prognostic value of interleukin 6 (IL-6), procalcitonin (PCT), and C-reactive protein (CRP) in critically ill patients during the first increase of fever, serum levels were measured in 38 patients admitted to intensive care unit of the Department of Medicine, Klinikum Grosshadern, University of Munich, immediately after increase of body temperature more than 38.3 degrees C. Ten healthy controls were also included for comparison. The onset of fever was accompanied by elevated circulating levels of all the 3 markers in comparison with healthy controls. However, only IL-6 levels were significantly higher (P < 0.05) in nonsurvivors (n = 21) compared with survivors. Sensitivity, specificity, positive, and negative predictive values calculated from median levels was higher for IL-6 compared with PCT and CRP. Areas under receiver characteristic operating curves revealed the highest area under the curve for IL-6 in contrast to PCT and CRP. These data suggest that IL-6 rather than PCT or CRP may be an early predictor of mortality in patients with onset of fever and identify patients, who need intensive monitoring to initiate appropriate therapy at an early stage.

[Atherogenesis: interplay between cholesterol, inflammation and coagulation]. / Atherogenese: Wechselspiel zwischen Cholesterin, Inflammation und Koagulation.

It is now generally accepted that, in addition to hypercholesterolemia, pro-inflammatory and procoagulatory factors play a major role in atherogenesis. Risk factors such as smoking, hypertension, diabetes and renal diseases alter lipoprotein profile and composition thus rendering them susceptible to modification. Modified lipoproteins induce local inflammation possibly due to activation of nuclear factor (NF-)kappaB and subsequent expression of adhesion molecules, release of pro-inflammatory cytokines, growth factors and mitogens, which are mediators for cell growth, proliferation and lipid deposition. Furthermore, activation of collagenases and proteases in combination with prothrombotic processes attenuate clot formation, plaque rupture and occlusion of vessels. Clinical as well as experimental studies suggest that elevated levels of pro-inflammatory markers may have a diagnostic potential. Thus, a therapeutic approach which modulates circulating cholesterol levels and improves pro-inflammatory and procoagulatory situation may prove beneficial as adjuvant therapy in atherosclerotic disease.

Heparin-mediated extracorporeal LDL precipitation treating a peripheral arterial disease patient suffering from repeated postoperative bypass occlusion.

Acute occlusion of a peripheral artery is a serious complication in peripheral arterial disease (PAD). Traditionally open surgical intervention in combination with antithrombotic therapy is the choice for treatment but the beneficial effects of both strategies are limited often by the patient's situation and therapeutic side effects. Heparin-mediated extracorporeal low-density lipoprotein precipitation (H.E.L.P.) apheresis efficiently removes circulating atherogenic lipoproteins, fibrinogen and C-reactive proteins as well as various proinflammatory and procoagulatory factors. We first report H.E.L.P. apheresis treating a PAD patient suffering from repeated postoperative femoropopliteal bypass graft occlusion, first, intensively, followed by weekly intervals. Limb amputation was avoided and the patient is doing well now. Angiography revealed bypass graft remained patent half a year after operation. This case report might help to design the regime for preventing postoperative bypass occlusion in patients with hyperlipidemia or hyperfibrinogenemia.

Heparin-mediated extracorporeal low-density lipoprotein precipitation: rationale for a specific adjuvant therapy in cardiovascular disease.

Various radical measures for the treatment of severe hypercholesterolemia such as partial ileal bypass, portocaval shunt, liver transplantation and plasma exchange have been tested in patients in whom drug and diet failed or were insufficient. Although effective, most of these treatments have severe side effects and are not routinely used. For hypercholesterolemic patients LDL-apheresis has proved to be the most promising and safe way as an adjuvant therapy. Several LDL-apheresis procedures with a varying degree of selectivity and efficiency have subsequently been developed. One of them is the H.E.L.P. system which was introduced in 1984 and has now been widely used. Besides the marked reduction of LDL particles by all techniques it has become apparent that only the H.E.L.P. system results in an equally significant change in hemostaseology, hemorheology and vasomotion because of its simultaneously removal of LDL, Lp(a), fibrinogen and CRP. This contribution reviews the application of the H.E.L.P. system as a valuable therapeutic tool for the treatment of various atherothrombotic and microcirculatory disorders such as prevention of early graft occlusion after coronary artery bypass grafting, treatment of peripheral vascular disease, stroke and preeclampsia.

Effects of heparin-mediated extracorporeal low-density lipoprotein precipitation beyond lowering proatherogenic lipoproteins--reduction of circulating proinflammatory and procoagulatory markers.

In addition to hypercholesterolemia, proinflammatory and prothrombotic markers have been suggested to play an important role in atherogenesis. We examined whether heparin-mediated extracorporeal low-density lipoprotein precipitation (HELP) therapy modulates the circulating levels of proinflammatory and prothrombotic markers. Twenty-two coronary heart disease (CHD) patients undergoing regular HELP-apheresis (18 males, 4 females, mean age 57.3 +/- 10.9 years) were enrolled in this study. A single HELP therapy treatment significantly decreased the circulating levels of high sensitivity C-reactive protein (hs-CRP), soluble vascular adhesion molecule-1 (sVCAM-1), soluble E-selectin, lipopolysaccharide binding protein (LBP), endothelin-1 (ET-1), and monocyte chemoattractant protein-1 (MCP-1) on average by 67, 37, 24, 27, 24, and 15%, respectively. Prothrombotic factors including fibrinogen, tissue factor (TF), soluble CD40 ligand (sCD40L), and homocysteine were decreased by 66, 27, 16, and 22%, respectively. In accordance with previous studies HELP therapy reduced total cholesterol, low density lipoprotein (LDL) cholesterol, and Lp(a) mass by 50, 61, and 62%, respectively. Our data suggest that simultaneous reduction of proinflammatory and prothrombotic factors together with atherogenic lipoproteins by HELP-apheresis may contribute to improvement of endothelial dysfunction and thereby inhibit progression of atherosclerotic lesions and stabilize the existing plaque.

Toll-like receptor expression in human keratinocytes: nuclear factor kappaB controlled gene activation by Staphylococcus aureus is toll-like receptor 2 but not toll-like receptor 4 or platelet activating factor receptor dependent.

Cultured primary human keratinocytes were screened for their expression of various members of the toll-like receptor (TLR) family. Keratinocytes were found to constitutively express TLR1, TLR2, TLR3, TLR5, and TLR9 but not TLR4, TLR6, TLR7, TLR8, or TLR10 as shown by polymerase chain reaction analysis. The expression of the crucial receptor for signaling of staphylococcal compounds TLR2 was also confirmed by immunohistochemistry, in contrast to TLR4, which showed a negative staining pattern. Next, we analyzed the activation of the proinflammatory nuclear transcription factor kappaB by Staphylococcus aureus strain 8325-4. Using nuclear extract gel shifts, RelA staining, and luciferase reporter transfection plasmids we found a clear induction of nuclear factor kappaB translocation by the bacteria. This translocation induced the transcription of nuclear factor kappaB controlled genes such as inducible nitric oxide synthetase, COX2, and interleukin-8. Transcription of these genes was followed by production of increased amounts of interleukin-8 protein and NO. Inhibition experiments using monoclonal antibodies and the specific platelet activating factor receptor inhibitor CV3988 showed that nuclear factor kappaB activation by S. aureus was TLR2 but not TLR4 or platelet activating factor receptor dependent. In line, the purified staphylococcal cell wall components lipoteichoic acid and peptidoglycan, known to signal through TLR2, also showed nuclear factor kappaB translocation in human keratinocytes, indicating a crucial role of the staphylococcal cell wall in the innate immune stimulation of human keratinocytes. These results help to explain the complex activation of human keratinocytes by S. aureus and its cell wall components in various inflammatory disorders of the skin.

Plasma atrial natriuretic peptide and brain natriuretic peptide are increased in septic shock: impact of interleukin-6 and sepsis-associated left ventricular dysfunction.

OBJECTIVE: Interest has recently focused on the use of neurohormonal markers such as atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) as indices of left ventricular systolic dysfunction and prognosis in heart failure. Also, peptides belonging to the interleukin-6 (IL-6) family have been shown to induce ANP and BNP secretion. We hypothesized that BNP and ANP spillover in the peripheral circulation reflects left ventricular dysfunction and IL-6 production in septic shock. DESIGN AND SETTING: Retrospective, clinical study in the medical intensive care unit of a university hospital. PATIENTS AND PARTICIPANTS: 17 patients with septic shock and 19 control subjects. INTERVENTIONS: Collection of clinical and demographic data in relation to ANP, BNP, IL-6, and soluble TNF receptors (sTNF-R-p55, sTNF-R-p75) in plasma over a period of 4 days. MEASUREMENTS AND RESULTS: In septic shock we found a significant increase in ANP (82.7+/-9.9 vs. 14.9+/-1.2 pg/ml) and BNP (12.4+/-3.6 vs. 5.5+/-0.7 pg/ml). Plasma ANP peaked together with IL-6. Peaks of ANP and IL-6 were significantly correlated (r=0.73; p<0.01). BNP was inversely correlated to cardiac index (r=-0.56; p<0.05). CONCLUSIONS: ANP and BNP increase significantly in patients with septic shock. BNP reflects left ventricular dysfunction. ANP is related to IL-6 production rather than to cardiovascular dysfunction.

Serum cholesterol levels in neutropenic patients with fever.

Hypocholesterolemia, which often accompanies infectious diseases has been suggested to serve as a prognostic marker in hospitalized patients. Even though patients with chemotherapy-induced leukopenia are at high risk of infection and mortality, only limited information is available on serum cholesterol levels in these patients. We therefore measured serum cholesterol levels in 17 patients with hematological malignancies during chemotherapy-induced neutropenia and correlated it with clinical outcome. Patients with fever (>38.5 degrees C) showed a significant decrease in serum cholesterol levels within 24 hours. Eight days after onset of the fever non-survivors had significantly lower serum cholesterol levels (median 2.09 mmol/l, range 0.49-2.79, n=6) compared to survivors (median 3.23 mmol/l, range 1.68-4.86, n=11). Cholesterol levels in survivors returned to baseline levels at the time of discharge from the hospital. At the onset of fever, serum levels of inflammatory cytokines interleukin-6, tumor necrosis factor (TNF) and soluble TNF receptors p55 and p75 were elevated in all patients, but only TNF and TNF receptor p75 levels were significantly different in survivors and non-survivors. Our data suggest that a decrease in serum cholesterol levels is a prognostic marker in neutropenic patients with fever. Release of inflammatory cytokines may in part be responsible for hypocholesterolemia in these patients.