Hmg-CoA reductase inhibitor modulates monocyte-endothelial cell interaction under physiological flow conditions in vitro: involvement of Rho GTPase-dependent mechanism

Pharmaceutical Modulation of Intracranial Aneurysm Development and Rupture

Management of intracranial aneurysms (IAs) is determined by patient age, risk of rupture, and comorbid conditions. While endovascular and microsurgical interventions offer solutions to mitigate the risk of rupture, pharmacological management strategies may complement these approaches or serve as alternatives in appropriate cases. The pathophysiology of IAs allows for the targeting of inflammation to prevent the development and rupture of IAs. The aim of this review is to provide an updated summary of different pharmaceutical management strategies for IAs. Acetylsalicylic acid and renin-angiotensin-aldosterone system (RAAS) inhibitor antihypertensives have some evidence supporting their protective effect. Studies of selective cyclooxygenase-2 (COX-2) inhibitors, statins, ADP inhibitors, and other metabolism-affecting drugs have demonstrated inconclusive findings regarding their association with aneurysm growth or rupture. In this manuscript, we highlight the evidence supporting each drug's effectiveness.

HMG-CoA reductase inhibitors and the attenuation of risk for disseminated intravascular coagulation in patients with sepsis

BACKGROUND

Disseminated Intravascular Coagulation (DIC) is a syndrome of dysregulated coagulation. Patients with sepsis are at increased risk for DIC. HMG-CoA Reductase Inhibitors (Statins) are primarily used as lipid-lowering agents; however, studies have suggested statins may possess anti-inflammatory, antithrombotic, anticoagulant, and endothelial stabilizing properties. These mechanisms may oppose those that underlie the pathogenesis of septic DIC.

METHODS

To evaluate whether statins may be protective against the development of DIC, we conducted a multi-center, retrospective case-control study where 86,638 critically ill patients admitted to the ICU with sepsis, severe sepsis or septic shock were identified during a 3-year period. Patients who developed DIC during their hospitalization were identified and stratified by whether they received a statin or not during their hospitalization. Odds ratios for development of DIC was calculated by composite of any statin, as well as low, moderate, and high intensity statins.

RESULTS

2236 patients would develop DIC compared to 84,402 who did not. The use of any statin was associated with a reduced likelihood for developing DIC (odds ratio [OR], 0.69; 95% CI, 0.61-0.78). This was observed with use of both moderate (OR, 0.64; 95% CI, 0.53-0.77) and high (OR, 0.72; 95% CI, 0.61-0.84) but not low intensity statins (OR, 0.84; 95% CI, 0.53-1.32).

CONCLUSIONS

The use of moderate and high intensity statins was associated with a significantly reduced odds of developing DIC in critically ill patients with sepsis. This present study may be the first to suggest that statin medications may independently reduce the frequency of DIC in critically ill patients with severe sepsis or septic shock. More research is needed to investigate the potential for this class of medication to be protective against DIC.

Can Simvastatin Reduce the Need for Immunomodulatory Drugs to Treat Uveitis?: A Prospective, Randomized, Placebo-Controlled Trial

Objective

To assess the efficacy of simvastatin 80 mg/day versus placebo in patients with noninfectious nonanterior uveitis receiving prednisolone ≥ 10 mg/day.

Design

Randomized, double-masked, controlled trial.

Subjects

Adult patients with noninfectious nonanterior uveitis on oral prednisolone dose of ≥ 10 mg/day.

Methods

Patients were randomly assigned at a 1:1 ratio to receive either simvastatin 80 mg/day or placebo. A total of 32 patients were enrolled (16 in each arm), all of whom completed the primary end point, and 21 reached the 2-year visit (secondary end points).

Main Outcome Measures

The primary end point was mean reduction in the daily prednisolone dose at 12 months follow-up. Secondary end points were mean reduction in prednisolone dose at 24 months, percent of patients with a reduction in second-line immunomodulatory agents, time to disease relapse, and adverse events.

Results

Our results show that simvastatin 80 mg/day did not have a significant corticosteroid-sparing effect at 12 months (estimate: 3.62; 95% confidence interval [CI]: -8.15 to 15.38; P = 0.54). There was no significant difference between the groups with regard to prednisolone dose or change in dose at 12 and 24 months. There was no difference between the 2 groups in percent of patients with reduction in second-line agent by 24 months. Among patients who achieved disease quiescence, the median time to first relapse was longer for those receiving simvastatin (38 weeks, 95% CI: 14-54) than placebo (14 weeks, 95% CI: 12-52), although this was not statistically significant. There was no significant difference in adverse events or serious adverse events between the 2 groups.

Conclusions

Simvastatin 80 mg/day did not have an effect on the dose reduction of corticosteroids or conventional immunomodulatory drugs at 1 and 2 years. The results suggest that it may extend the time to disease relapse among those who achieve disease quiescence.

Financial Disclosures

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Neutrophil Protein Kinase R Mediates Endothelial Adhesion and Migration by the Promotion of Neutrophil Actin Polymerization

Neutrophils protect against bacterial and fungal infections, but tight regulation of cell activation is essential for avoiding tissue damage in autoimmune disorders. Protein kinase R (PKR) is a serine/threonine kinase originally characterized by its role in the defense mechanisms against viral infection. Although PKR is involved in the signaling pathways of neurodegenerative diseases and metabolic disorders, its function in neutrophils is not well delineated. In this study, we demonstrate that human neutrophil PKR mediates adhesion to endothelial cells under physiological flow conditions but does not mediate rolling on those cells. Also, neutrophil PKR activation contributes to migration toward chemoattractants. Mechanistically, neutrophil PKR mediates the cell spreading and binding to ICAM-1 in static condition. Moreover, Ab microarray reveals that calcium/calmodulin-dependent protein kinase II is phosphorylated downstream of PKR and affects actin polymerization that is a cytoskeleton rearrangement indispensable for neutrophil migration induced by fMLF. In vivo, neutrophil recruitment into the dorsal air pouch of mice is reduced by PKR inhibitor treatment. Also, in mice with nephrotoxic serum nephritis, the compound treatment suppresses neutrophil accumulation in kidney glomerulus and subsequent development of albuminuria. Thus, in vascular inflammation, neutrophil PKR plays a critical role in the recruitment process, including endothelial adhesion and migration via leukocyte actin polymerization.

CXCL1-Triggered PAD4 Cytoplasmic Translocation Enhances Neutrophil Adhesion through Citrullination of PDIA1

Aims: Vascular inflammation is critical for the development and progression of atherosclerosis. Previously, we reported that neutrophils adhere to the vascular endothelium in low-density lipoprotein receptor null mice fed a high-fat diet through hypercitrullination of histone H3 by peptidylarginine deiminase 4 (PAD4) in neutrophils. However, the involvement of PAD4 and citrullination of proteins other than histone H3 in neutrophil adhesion is not well known. In this study, we investigated the function of PAD4 and identified citrullinated proteins during vascular inflammation.

Methods: We pefformed flow assay under physiological flow conditions using differentiated HL-60 (dHL-60) cells stimulated with CXCL1 and human umbilical vein endothelial cells (HUVECs). Furthermore, phalloidin stain for dHL-60 stimulated with CXCL1 to observe F-actin polymerization and immunohistochemistry for the activated β2-integrin was conducted. To identify a target of citrullination in the cytoplasm of dHL-60 cells, liquid chromatography-mass spectrometry (LC-MS/MS) for dHL-60 stimulated with CXCL1 was performed.

Results: Inhibition or knockdown of PAD4 significantly decreased adhesion of under physiological flow conditions. Thr-Asp-F-amidine trifluoroacetate salt (TDFA), a PAD4 inhibitor, inhibited cytoplasmic translocation of PAD4 by CXCL1. TDFA or knockdown of PAD4 significantly decreased expression of β2-integrin and F-actin polymerization activated by CXCL1. Moreover, LC-MS/MS identified protein disulfide isomerase A1 (PDIA1) as a target of citrullination in the cytoplasm of dHL-60 cells. Knockdown of PDIA1 significantly decreased adhesion of dHL-60 cells to HUVECs, expression of β2-integrin, and F-actin polymerization.

Conclusions: Cytoplasmic translocation of PAD4 by CXCL1 induces neutrophil adhesion to vascular endothelial cells and citrullination of PDIA1.

Statins reduce vascular inflammation in atherogenesis: A review of underlying molecular mechanisms

Chronic inflammation enhances the detrimental role of dyslipidaemia during atherogenesis. Statins are among the most effective anti-atherosclerotic medications, being able to impact on both cardiovascular morbidity and mortality. Although these molecules have been first described as lipid-lowering medications, several lines of evidence suggest additional benefits through their "pleiotropic" anti-atherosclerotic activities. Specifically, statins can modulate vascular atherosclerotic inflammation by directly improving functions of endothelial cells, vascular smooth muscle cells, platelets, and immune cells. Here, we discuss basic and clinical evidence to provide an update on the molecular mechanisms underlying the protective anti-inflammatory role of statins in atherogenesis.

Nanoparticle-Mediated Targeting of Pitavastatin to Small Pulmonary Arteries and Leukocytes by Intravenous Administration Attenuates the Progression of Monocrotaline-Induced Established Pulmonary Arterial Hypertension in Rats

Statins are known to improve pulmonary arterial hypertension (PAH) by their anti-inflammatory and anti-proliferative effects in animal models. However, recent clinical studies have reported that clinically approved statin doses failed to improve clinical outcomes in patients with PAH. We therefore hypothesized that nanoparticle (NP) -mediated targeting of pitavastatin could attenuate the progression of established PAH.We induced PAH by subcutaneously injecting monocrotaline (MCT) in Sprague-Dawley rats. On day 14 after the MCT injection, animals that displayed established PAH on echocardiography were included. On day 17, they were randomly assigned to the following 5 groups: daily intravenous administration of (1) vehicle, (2) fluorescein-isothiocyanate-NP, (3) pitavastatin, (4) pitavastatin-NP, or (5) oral sildenafil. Intravenous NP was selectively delivered to small pulmonary arteries and circulating CD11b-positive leukocytes. On day 21, pitavastatin-NP attenuated the progression of PAH at lower doses than pitavastatin alone. This was associated with the inhibition of monocyte-mediated inflammation, proliferation, and remodeling of the pulmonary arteries. Interestingly, sildenafil attenuated the development of PAH, but had no effects on inflammation or remodeling of the pulmonary arteries. In separate experiments, only treatment with pitavastatin-NP reduced the mortality rate at day 35.NP-mediated targeting of pitavastatin to small pulmonary arteries and leukocytes attenuated the progression of established MCT-induced PAH and improved survival. Therapeutically, pitavastatin-NP was associated with anti-inflammatory and anti-proliferative effects on small pulmonary arteries, which was completely distinct from the vasodilatory effect of sildenafil. Pitavastatin-NP can be a novel therapeutic modality for PAH.

7-Ketocholesterol enhances leukocyte adhesion to endothelial cells via p38MAPK pathway

7-Ketocholesterol is a major dietary cholesterol oxidation product found in high concentrations in atherosclerotic plaques, which contribute to the development of atherosclerosis. This study aimed to investigate the effects of 7-ketocholesterol on endothelial inflammation, as well as the underlying mechanisms. Pretreatment of human umbilical vein endothelial cells (HUVEC) with 7-ketocholesterol significantly enhanced the total interactions between human monocytic cells (THP-1 cell line) and TNFα-activated HUVECs under physiological flow conditions, compared to pretreatment with cholesterol (TNFα+50 μM cholesterol: 13.1 ± 0.54 cells/CPF, TNFα+50 μM 7-ketocholesterol: 18.9 ± 0.35 cells/CPF, p < 0.01). 7-Ketocholesterol enhanced the expression of E-selectin, ICAM-1, and VCAM-1 proteins. It also activated p38 mitogen-activated protein kinase (MAPK), and treatment with a p38 MAPK inhibitor inhibited both E-selectin expression via ATF-2 activation and 7-ketocholesterol-induced THP-1 adhesion to HUVECs. These findings suggest that 7-ketocholesterol enhances leukocyte–endothelial interactions by upregulating the expression of adhesion molecules, presumably via the p38 MAPK-dependent pathway.

'Statins in retinal disease'

Statins are known for their blood cholesterol-lowering effect and are widely used in patients with cardiovascular and metabolic diseases. Research over the past three decades shows that statins have diverse effects on different pathophysiological pathways involved in angiogenesis, inflammation, apoptosis, and anti-oxidation, leading to new therapeutic options. Recently, statins have attracted considerable attention for their immunomodulatory effect. Since immune reactivity has been implicated in a number of retinal diseases, such as uveitis, age-related macular degeneration (AMD) and diabetic retinopathy, there is now a growing body of evidence supporting the beneficial effects of statins in these retinopathies. This review evaluates the relationship between statins and the pathophysiological basis of these diseases, focusing on their potential role in treatment. A PubMed database search and literature review was conducted. Among AMD patients, there is inconsistent evidence regarding protection against development of early AMD or delaying disease progression; though they have been found to reduce the risk of developing choroidal neovascular membranes (CNV). In patients with retinal vein occlusion, there was no evidence to support a therapeutic benefit or a protective role with statins. In patients with diabetic retinopathy, statins demonstrate a reduction in disease progression and improved resolution of diabetic macular oedema (DMO). Among patients with uveitis, statins have a protective effect by reducing the likelihood of uveitis development.

The Anti-Inflammatory Effects of Statins on Coronary Artery Disease: An Updated Review of the Literature

Background:

Statins have long been used for the protection against coronary artery disease (CAD). Their beneficial effect apart from cholesterol reduction lies in their pleiotropic properties. Emerging evidence from laboratory studies and clinical trials as well have pointed out the pivotal role of inflammation on the initiation and exacerbation of atherosclerosis; a major cause of CAD. Inflam-mation markers such as high sensitivity C-reactive protein and adhesion molecules are shown to in-crease in CAD patients and are used as prognostic tools. It is well known that statins can actually re-duce the circulating levels of these agents slowing therefore the inflammatory process; interestingly not all types have the same outcome.

Conclusion:

The anti-inflammatory effect of statins on the formation of atherosclerotic plaque and the function of endothelial cells is thus of particular importance as these agents can actually ameliorate CAD prognosis

Pulmonary Infections in the Elderly Lead to Impaired Neutrophil Targeting, Which Is Improved by Simvastatin

RATIONALE

Dysregulated neutrophil functions with age and sepsis are described. Statins are associated with improved infection survival in some observational studies, but trials in critically ill patients have not shown benefit. Statins also alter neutrophil responses in vitro.

OBJECTIVES

To assess neutrophil migratory accuracy with age during respiratory infections and determine if and how a statin intervention could alter these blunted responses.

METHODS

The migratory accuracy of blood neutrophils from young (aged <35 yr) and old (aged >60 yr) patients in health and during a lower respiratory tract infection, community-acquired pneumonia, and pneumonia associated with sepsis was assessed with and without simvastatin. In vitro results were confirmed in a double-blind randomized clinical trial in healthy elders. Cell adhesion markers were assessed.

MEASUREMENTS AND MAIN RESULTS

In vitro neutrophil migratory accuracy in the elderly deteriorated as the severity of the infectious pulmonary insult increased, without recovery at 6 weeks. Simvastatin rescued neutrophil migration with age and during mild to moderate infection, at high dose in older adults, but not during more severe sepsis. Confirming in vitro results, high-dose (80-mg) simvastatin improved neutrophil migratory accuracy without impeding other neutrophil functions in a double-blind randomized clinical trial in healthy elders. Simvastatin modified surface adhesion molecule expression and activity, facilitating accurate migration in the elderly.

CONCLUSIONS

Infections in older adults are associated with prolonged, impaired neutrophil migration, potentially contributing to poor outcomes. Statins improve neutrophil migration in vivo in health and in vitro in milder infective events, but not in severe sepsis, supporting their potential utility as an early intervention during pulmonary infections. Clinical trial registered with www.clinicaltrialsregister.eu (2011-002082-38).

Distinct impact of three different statins on arteriovenous fistula outcomes: a retrospective analysis

PURPOSE

Whether statins improve arteriovenous fistula (AVF) outcomes is still a matter of debate. Taking into consideration the existing physicochemical differences between individual drugs, this study evaluates the impact of three different statins (atorvastatin, rosuvastatin and simvastatin) on one-stage and two-stage AVF outcomes.

METHODS

Using a retrospective cohort of 535 patients, we analyzed the effects of each statin on primary failure and primary patency using multivariate logistic regressions and Cox proportional hazard models.

RESULTS

Out of the three statins analyzed, only atorvastatin improved the overall primary failure of AVF (odds ratio [OR] = 0.18, p = 0.005). Comparisons between the two AVF types demonstrated that this effect was due to a prominent reduction in primary failure of one-stage (OR = 0.03; p = 0.005), but not two-stage fistulas (OR = 0.43; p = 0.25). In contrast, primary patency of two-stage (hazards ratio [HR] = 0.51; p = 0.024), but not one-stage fistulas (HR = 0.98; p = 0.95), was improved by all statins as a group, but not by individual drugs.

CONCLUSIONS

Our results suggest that the potential benefit of statins on AVF outcomes is a drug-specific and not a class effect, and that such effect is also influenced by the type of fistula.

Synergistic Inhibitory Effect of Rosuvastatin and Angiotensin II Type 2 Receptor Agonist on Vascular Remodeling

We investigated the possibility that coadministration of rosuvastatin and compound 21 (C21), a selective angiotensin II type 2 (AT2) receptor agonist, could exert synergistic preventive effects on vascular injury. Vascular injury was induced by polyethylene cuff placement on the femoral artery in 9-week-old male C57BL/6J mice. Mice were treated with rosuvastatin and/or with C21 after cuff placement. Neointima formation was determined 14 days after the operation and cell proliferation, and superoxide anion production and expression of inflammatory cytokines were examined 7 days after cuff placement. Neointima formation was significantly attenuated by the treatment of rosuvastatin (5 mg kg(-1) day(-1)) or C21 (10 μg kg(-1) day(-1)), associated with the decreases in proliferating cell nuclear antigen (PCNA) labeling index, oxidative stress, and the expression of inflammatory markers. Treatment with a noneffective dose of rosuvastatin (0.5 mg kg(-1) day(-1)) plus a low dose of C21 (1 μg kg(-1) day(-1)) inhibited the PCNA labeling index, superoxide anion production, mRNA expressions of NAD(P)H subunits, and mRNA and protein expressions of inflammatory markers associated with marked inhibition of neointima formation. Angiotensin II type 1 (AT1) receptor mRNA expression did not differ the groups. By contrast, AT2 receptor mRNA expression was increased by administration of C21 at the dose of 10 μg kg(-1) day(-1) but not by C21 at the dose of 1 μg kg(-1) day(-1) or rosuvastatin. The combination of rosuvastatin and AT2 receptor agonist exerted synergistic preventive effects on vascular remodeling associated with the decreases in cell proliferation, oxidative stress, and inflammatory reaction. That could be a powerful approach to vascular disease prevention.

Inhibitory Effect of Serotonin Antagonist on Leukocyte-Endothelial Interactions In Vivo and In Vitro

Background

Although 5-HT_2A serotonergic antagonists have been used to treat vascular disease in patients with diabetes mellitus or obesity, their effects on leukocyte-endothelial interactions have not been fully investigated. In this study, we assessed the effects of sarpogrelate hydrochloride (SRPO), a 5-HT_2A receptor inverse agonist, on leukocyte-endothelial cell interactions in obesity both in vivo and in vitro.

Methods and Findings

In the in vivo experiment, C57BL/6 mice were fed a high-fat high-fructose diet (HFFD), comprising 20% fat and 30% fructose, with or without intraperitoneal injection of 5 mg/kg/day SRPO for 4 weeks. The body weight, visceral fat weight, and serum monocyte chemoattractant protein-1 levels in the mice increased significantly with the HFFD, but these effects were prevented by chronic injections of SRPO. Intravital microscopy of the femoral artery detected significant leukocyte-endothelial interactions after treatment with HFFD, but these leukocyte-endothelial interactions were reduced in the mice injected with SRPO. In the in vitro experiment, pre-incubation of activated human umbilical vein endothelial cells (HUVECs) with platelet-rich plasma (PRP) induced THP-1 cell adhesion under physiological flow conditions, but the adhesion was reduced by pretreatment of PRP with SRPO. A fluorescent immunobinding assay showed that PRP induced significant upregulation of E-selectin in HUVECs, but this upregulation was reduced by pretreatment of PRP with SRPO. In other in vitro conditions, pre-incubation of THP-1 cells with phorbol 12-myristate 13-acetate increased the adhesion of THP-1 cells to activated HUVECs under rotational conditions, but this adhesion was reduced by pretreatment with SRPO. Western blotting analysis showed that protein kinase C α activation in THP-1 cells was inhibited by SRPO.

Conclusion

Our findings indicated that SRPO inhibits vascular inflammation in obesity via inactivation of platelets and leukocytes, and improvement of obese.

Simvastatin Inhibits Toll-like Receptor 8 (TLR8) Signaling in Primary Human Monocytes and Spontaneous Tumor Necrosis Factor Production from Rheumatoid Synovial Membrane Cultures

Simvastatin has been shown to have antiinflammatory effects that are independent of its serum cholesterol lowering action, but the mechanisms by which these antiinflammatory effects are mediated have not been elucidated. To explore the mechanism involved, the effect of simvastatin on toll-like receptor (TLR) signaling in primary human monocytes was investigated. A short pretreatment with simvastatin dose-dependently inhibited the production of tumor necrosis factor (TNF)-α in response to TLR8 activation (but not TLR2, -4 or -5). Statins are known inhibitors of the cholesterol biosynthetic pathway, but, intriguingly, TLR8 inhibition could not be reversed by addition of mevalonate or geranylgeranyl pyrophosphate, downstream products of cholesterol biosynthesis. TLR8 signaling was examined in HEK 293 cells stably expressing TLR8, where simvastatin inhibited I kappa B kinase (IKK)α/β phosphorylation and subsequent nuclear factor (NF)-κB activation without affecting the pathway to activating protein-1 (AP-1). Because simvastatin has been reported to have antiinflammatory effects in RA patients and TLR8 signaling contributes to TNF production in human RA synovial tissue in culture, simvastatin was tested in these cultures. Simvastatin significantly inhibited the spontaneous release of TNF in this model, which was not reversed by mevalonate. Together, these results demonstrate a hitherto unrecognized mechanism of simvastatin inhibition of TLR8 signaling that may in part explain its beneficial antiinflammatory effects.

Association between statin use and uveitis: results from the Pacific Ocular Inflammation study

PURPOSE

To assess whether there is a protective association between statin use and uveitis diagnosis.

DESIGN

Retrospective, population-based case-control study.

METHODS

Medical records of all patients in the Kaiser Permanente Hawaii health plan between January 1, 2006 and December 31, 2007 (N = 217 061) were searched electronically for International Classification of Diseases, 9th Revision, diagnosis codes related to uveitis. Chart review was done to confirm incident uveitis diagnosis during the study period. Two control groups were each randomly selected at a 5:1 ratio to cases, and controls were assigned an index date to match their respective case diagnosis date. One control group was selected from the general Kaiser Permanente Hawaii population that had at least 1 healthcare visit during the study period. Another control group was selected from the population of Kaiser Permanente Hawaii members who had at least 1 visit to the ophthalmology clinic during the study period. Statin use was defined as filling a prescription for statin medication in the year prior to the diagnosis or index date based on an electronic search of the Kaiser Permanente Hawaii pharmacy database for Generic Product Identification codes. A conditional logistic regression model with clinical diagnosis of uveitis as the outcome was used to assess the relationship between statin use and uveitis.

RESULTS

One hundred eight incident cases of uveitis were identified. Nineteen percent of uveitis patients had used statin medication in the year prior to diagnosis compared to 30% of patients in the general Kaiser population control (P = .03) and 38% of patients in the ophthalmology clinic control (P < .001). Using the general Kaiser population control and adjusting for age, sex, race, and autoimmune diseases, the odds of a statin user developing uveitis were 48% less than the odds of a non-statin user developing uveitis (OR: 0.52, 95% CI: 0.29-0.94, P = .03). Similarly, the odds of developing uveitis were 33% less for statin users compared to non-statin users (OR: 0.67, 95% CI: 0.38-1.19, P = .17) when adjusting for these factors and using the ophthalmology clinic control group.

CONCLUSIONS

Statin use may be protective against the development of uveitis. Several anti-inflammatory and immunomodulatory mechanisms may explain this association.

High-dose atorvastatin ameliorates the uterine microenvironment in streptozotocin-induced diabetic rats

Abstract The aim of this study was to investigate whether atorvastatin can ameliorate the uterine microenvironment in diabetes mellitus. Six non-diabetic (control) and 12 diabetic mature female Sprague-Dawley albino rats were used in this study. Diabetes was induced by intraperitoneal injections of 60 mg/kg streptozotocin, and 10 mg/kg/day of oral atorvastatin was administered for 4 weeks via orogastric tubes. The animals were euthanized, and blood samples were collected via cardiac puncture for biochemical analysis. Bilateral hysterectomy was performed for the histopathologic examination. Endometrial gland degeneration and stromal fibrosis scores concomitant with epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) immunoexpressions were analyzed. The endometrial gland degeneration scores, stromal fibrosis scores and VEGF immunoexpression was significantly lower, and the EGFR immunoexpression was significantly higher in the atorvastatin-treated diabetic rats when compared to the non-treated diabetic group, suggesting that atorvastatin ameliorates the uterine microenvironment in diabetes mellitus.

Simvastatin down-regulates the production of interleukin-8 by neutrophil leukocytes from dyslipidemic patients

BACKGROUND

Neutrophil (PMN) leukocytes participate to the initial phases of atherosclerosis through the release of Interleukin 8 (CxCL8; IL-8) that contribute to amplification of inflammation. Aim of the study is to investigate the production of IL-8 by PMN leukocytes from dyslipidemic patients treated with simvastatin.

METHODS

In 15 dyslipidemic subjects with moderately increased cardiovascular risk, assessed by Framingham Risk Score, blood samples were obtain to investigate PMNs IL-8 production [at baseline and after N-formyl-Met-Leu-Phe (fMLP) stimulation] before and after long-term (1-year) simvastatin treatment.

RESULTS

The resting release of IL-8 was higher in dyslipidemic patients at baseline when compared with control subjects (p < 0.05). One year of treatment was significantly associated with reduced IL-8 production (p < 0.01). Moreover, the fMLP-induced IL-8 production in dyslipidemic untreated patients was higher than that of controls (p < 0.05) and was reduced after simvastatin treatment (p < 0.01). IL-8 release after 1 year of treatment was reduced to levels which were lower than those observed in control subjects both for resting and stimulated cytokine production (p < 0.01).

CONCLUSIONS

Prolonged treatment with simvastatin is associated with a reduction of IL-8 production, suggesting the possibility of statin to modulate the pro-inflammatory response in PMNs of patients with moderately increased cardiovascular risk.

Antithrombotic actions of statins involve PECAM-1 signaling

Statins are widely prescribed cholesterol-lowering drugs that are a first-line treatment of coronary artery disease and atherosclerosis, reducing the incidence of thrombotic events such as myocardial infarction and stroke. Statins have been shown to reduce platelet activation, although the mechanism(s) through which this occurs is unclear. Because several of the characteristic effects of statins on platelets are shared with those elicited by the inhibitory platelet adhesion receptor PECAM-1 (platelet endothelial cell adhesion molecule-1), we investigated a potential connection between the influence of statins on platelet function and PECAM-1 signaling. Statins were found to inhibit a range of platelet functional responses and thrombus formation in vitro and in vivo. Notably, these effects of statins on platelet function in vitro and in vivo were diminished in PECAM-1(-/-) platelets. Activation of PECAM-1 signaling results in its tyrosine phosphorylation, the recruitment and activation of tyrosine phosphatase SHP-2, the subsequent binding of phosphoinositol 3-kinase (PI3K), and diminished PI3K signaling. Statins resulted in the stimulation of these events, leading to the inhibition of Akt activation. Together, these data provide evidence for a fundamental role of PECAM-1 in the inhibitory effects of statins on platelet activation, which may explain some of the pleiotropic actions of these drugs.

Huang Qi Jian Zhong Pellet Attenuates TNBS-Induced Colitis in Rats via Mechanisms Involving Improvement of Energy Metabolism

Huang Qi Jian Zhong Pellet (HQJZ) is a famous Chinese medicine formula for treatment of various gastrointestinal tract diseases. This study investigated the role of HQJZ in 2,4,6-trinitrobenzene sulfonic acid- (TNBS-) induced colitis and its underlying mechanism. Colonic mucosal injury was induced by TNBS in the Sprague-Dawley rats. In the HQJZ treatment group, HQJZ was administered (2 g/kg) for 14 days starting from day 1 after TNBS infusion. Colonic mucosal injury occurred obviously 1 day after TNBS challenge and did not recover distinctively until day 15, including an increase in macro- and microscopic scores, a colonic weight index, a decrease in colonic length, a number of functional capillaries, and blood flow. Inverted intravital microscopy and ELISA showed colonic microcirculatory disturbances and inflammatory responses after TNBS stimulation, respectively. TNBS decreased occludin, RhoA, and ROCK-I, while increasing Rac-1, PAK-1, and phosphorylated myosin light chain. In addition, ATP content and ATP5D expression in colonic mucosa decreased after TNBS challenge. Impressively, treatment with HQJZ significantly attenuated all of the alterations evoked by TNBS, promoting the recovery of colonic injury. The present study demonstrated HQJZ as a multitargeting management for colonic mucosal injury, which set in motion mechanisms involving improvement of energy metabolism.

Statin use and ocular inflammatory disease risk

Background

This study aims to evaluate the effect of oral statin medication use on the subsequent development of ocular inflammatory disease (OID). A retrospective nested case–control study was carried out on patient records from the Birmingham Veterans Affairs Medical Center. All male patients with a new diagnosis of OID over a 5-year period were included. Ten control subjects (without OID) were age-matched to each OID case. Prescription files of all subjects were queried for statin use. Information on selected comorbid medical conditions was also obtained. Conditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for risk of OID development in the context of statin use, controlling for comorbid conditions.

Results

Ninety-two incident cases of OID were identified. A trend toward a reduction in the risk of new OID development was found in patients that used statins compared to those that did not (OR 0.50, 95% CI 0.20 to 1.23, p = 0.13). The longer the duration of statin use, the greater is the effect.

Conclusions

Use of oral statins may be associated with a reduced risk for the development of OID. This reduced risk increases with increasing duration of use. Larger clinical studies would be required to definitively establish the effectiveness of statins in lowering the incidence of OID.

Simvastatin inhibits sphingosylphosphorylcholine-induced differentiation of human mesenchymal stem cells into smooth muscle cells

Sphingosylphosphorylcholine (SPC) induces differentiation of human adipose tissue-derived mesenchymal stem cells (hASCs) into smooth muscle-like cells expressing α-smooth muscle actin (α-SMA) via transforming growth factor-β1/Smad2- and RhoA/Rho kinase-dependent mechanisms. 3-Hydroxy-3-methylglutaryl- coenzyme A reductase inhibitors (statins) have been known to have beneficial effects in the treatment of cardiovascular diseases. In the present study, we examined the effects of simvastatin on the SPC-induced α-SMA expression and Smad2 phosphorylation in hASCs. Simvastatin inhibited the SPC-induced α-SMA expression and sustained phosphorylation of Smad2 in hASCs. SPC treatment caused RhoA activation via a simvastatin-sensitive mechanism. The SPC-induced α-SMA expression and Smad2 phosphorylation were abrogated by pretreatment of the cells with the Rho kinase inhibitor Y27632 or overexpression of a dominant negative RhoA mutant. Furthermore, SPC induced secretion of TGF-β1 and pretreatment with either Y27632 or simvastatin inhibited the SPC-induced TGF-β1 secretion. These results suggest that simvastatin inhibits SPC-induced differentiation of hASCs into smooth muscle cells by attenuating the RhoA/Rho kinase-dependent activation of autocrine TGF-β1/Smad2 signaling pathway.

Rosiglitazone regulates c-reactive protein-induced inflammatory responses via glucocorticoid receptor-mediated inhibition of p38 mitogen-activated protein kinase-toll-like receptor 4 signal pathway in vascular smooth muscle cells

C-reactive protein (CRP) activates toll-like receptor 4 (TLR4) to initiate inflammatory response involved in the pathogenesis of atherosclerosis through mitogen-activated protein kinase (MAPK) signal pathways. Rosiglitazone, a synthetic peroxisome proliferator-activated receptor γ (PPARγ) agonist, is considered to be an important inhibitor of the inflammatory response. The present study was to explore the effect of rosiglitazone on the CRP-induced inflammatory responses and the related signal pathway in vascular smooth muscle cells (VSMCs). The results showed that rosiglitazone reduced the expressions of proinflammatory cytokines, such as vascular endothelial growth factor-A and inducible nitric oxide synthase, and enhanced the expression or activation of anti-inflammatory transcription factors including PPARγ and glucocorticoid receptor (GR) in VSMCs in response to CRP. The further investigations indicated that rosiglitazone inhibited CRP-induced TLR4 expression and p38 MAPK phosphorylation in VSMCs, and TLR4 knockdown potentiated the inhibitory effects of rosiglitazone on vascular endothelial growth factor-A and inducible nitric oxide synthase expressions. In addition, GR antagonist RU486 but not PPARγ inhibitor GW9662 remarkably weakened the inhibitory effects of rosiglitazone on CRP-induced TLR4 expression and p38 phosphorylation in VSMCs. But GW9662 did not affect rosiglitazone-induced GR phosphorylation. These suggest that rosiglitazone exerts its anti-inflammatory effect through activating GR and subsequently inhibiting p38 MAPK-TLR4 signaling pathway in CRP-stimulated VSMCs.

High dose atorvastatin decreases cellular markers of immune activation without affecting HIV-1 RNA levels: results of a double-blind randomized placebo controlled clinical trial

BACKGROUND

3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors (statins) exhibit antiviral activity against human immunodeficiency virus type 1 (HIV-1) in vitro and may modulate the immune response to HIV infection. Studies evaluating the antiviral activity of statins have yielded conflicting results.

METHODS

We conducted a randomized, double-blind, placebo-controlled crossover trial to investigate the effect of atorvastatin on HIV-1 RNA (primary objective) and cellular markers of immune activation (secondary objective). HIV-infected individuals not receiving antiretroviral therapy were randomized to receive either 8 weeks of atorvastatin (80 mg) or placebo daily. After a 4-6 week washout phase, participants switched treatment assignments. The study had 80% power to detect a 0.3 log(10) decrease in HIV-1 RNA level. Expression of CD38 and HLA-DR on CD4(+) and CD8(+) T cells was used to measure immune activation.

RESULTS

Of 24 randomized participants, 22 completed the study. Although HIV-1 RNA level was unaffected by the intervention (-0.13 log(10) copies/mL; P = .85), atorvastatin use resulted in reductions in circulating proportions of CD4(+) HLA-DR(+) (-2.5%; P = .02), CD8(+) HLA-DR(+) (-5%; P = .006), and CD8(+) HLA-DR(+) CD38(+) T cells (-3%; P = .03). Reductions in immune activation did not correlate with declines in serum levels of low-density lipoprotein cholesterol.

CONCLUSIONS

Short-term use of atorvastatin was associated with modest but statistically significant reductions in the proportion of activated T lymphocytes.

Combination of amlodipine and atorvastatin synergistically reduces leukocyte recruitment to mechanically injured mouse femoral artery

Recent studies have demonstrated a potential synergistic effect of the combination of amlodipine with atorvastatin to reduce acute inflammation. The intraluminal wire injury of the mouse femoral artery induced significant leukocyte recruitment to the injured area and oxidative stress within 24 h. Administration of low-dose amlodipine (0.5 mg kg(-1) per day) or atorvastatin (1 mg kg(-1) per day) alone for 7 days failed to modulate leukocyte adhesion, whereas their co-administration for 7 days significantly inhibited leukocyte adhesion. Moreover, flow cytometric analysis showed that injury-induced oxidative stress and CD11b expression in three leukocyte fractions were elevated after injury and then reduced after the co-administration. Next, adoptive transfer of mononuclear cells (MNCs) was performed and MNCs were harvested from mice after wire injury exhibited adhesion to the recipient injured artery. Furthermore, the co-administration of low-dose atorvastatin and amlodipine to MNCs or the vasculature reduced the recruitment of MNCs to the injured artery. Our findings indicate that amlodipine and atorvastatin synergistically inhibit vascular inflammation. The underlying mechanisms of their effect involve, at least in part, stabilizing oxidative stress at the point of injury, suggesting the clinical efficacy of this drug combination for the treatment of vascular diseases.

Indoxyl sulfate induces leukocyte-endothelial interactions through up-regulation of E-selectin

Despite a positive correlation between chronic kidney disease and atherosclerosis, the causative role of uremic toxins in leukocyte-endothelial interactions has not been reported. We thus examined the effects of indoxyl sulfate, a uremic toxin, on leukocyte adhesion to activated endothelial cells and the underlying mechanisms. Pretreatment of human umbilical vein endothelial cells (HUVEC) with indoxyl sulfate significantly enhanced the adhesion of human monocytic cells (THP-1 cell line) to TNF-α-activated HUVEC under physiological flow conditions. Treatment with indoxyl sulfate enhanced the expression level of E-selectin, but not that of ICAM-1 or VCAM-1, in HUVEC. Indoxyl sulfate treatment enhanced the activation of JNK, p38 MAPK, and NF-κB in TNF-α-activated HUVEC. Inhibitors of JNK and NF-κB attenuated indoxyl sulfate-induced E-selectin expression in HUVEC and subsequent THP-1 adhesion. Furthermore, treatment with the NAD(P)H oxidase inhibitor apocynin and the glutathione donor N-acetylcysteine inhibited indoxyl sulfate-induced enhancement of THP-1 adhesion to HUVEC. Next, we examined the in vivo effect of indoxyl sulfate in nephrectomized chronic kidney disease model mice. Indoxyl sulfate-induced leukocyte adhesion to the femoral artery was significantly reduced by anti-E-selectin antibody treatment. These findings suggest that indoxyl sulfate enhances leukocyte-endothelial interactions through up-regulation of E-selectin, presumably via the JNK- and NF-κB-dependent pathway.

Geranylgeraniol prevents the cytotoxic effects of mevastatin in THP-1 cells, without decreasing the beneficial effects on cholesterol synthesis

BACKGROUND AND PURPOSE

Statins, inhibitors of hydroxymethylglutaryl-CoA reductase, reduce the intracellular synthesis of cholesterol and prevent the onset of atherosclerosis. They also decrease the synthesis of isoprenoid molecules, such as the side chain of ubiquinone and geranylgeranyl pyrophosphate. As a consequence, statins impair mitochondrial metabolism and the activation of small monomeric GTPases (such as Rho and Ras), causing toxic effects. To date, a successful strategy to prevent statin toxicity is lacking.

EXPERIMENTAL APPROACH

In human monocytic THP-1 cells, we measured the synthesis of cholesterol and isoprenoids, mitochondrial electron flow, the activity of RhoA and Rac, cell death and proliferation.

KEY RESULTS

Mevastatin reduced the synthesis of cholesterol, geranylgeranyl pyrophosphate and ubiquinone, mitochondrial electron transport, activity of RhoA and Rac, and cell proliferation, accompanied by increased cell death. Geranylgeraniol, a cell-permeable analogue of geranylgeranyl pyrophosphate, reversed all these effects of mevastatin, without affecting its ability to reduce cholesterol synthesis. Notably, geranylgeraniol was more effective than the addition of exogenous ubiquinone, which rescued mitochondrial respiratory activity and reversed mevastatin cytotoxicity, but did not alter the decrease in cell proliferation. The same results were obtained in human liver HepG2 cells.

CONCLUSIONS AND IMPLICATIONS

Geranylgeraniol had a broader protective effect against the cytotoxicity of statins than exogenous ubiquinone. Therefore, geranylgeraniol may be a more useful and practical means of limiting the toxicities of statins, without reducing their efficacy as cholesterol lowering agents.

Atherosclerosis induced by chronic inhibition of the synthesis of nitric oxide in moderately hypercholesterolaemic rabbits is suppressed by pitavastatin

BACKGROUND AND PURPOSE

It is not clear if the new 3-hydroxyl-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor pitavastatin prevents atherogenesis by a direct effect. Statins have a cholesterol-lowering effect, so an accessible animal model of atherosclerosis showing only moderate hypercholesterolaemia as in humans, is needed. The effects of pitavastatin were evaluated on atherosclerotic lesions accumulating foam cells derived from macrophages, produced in rabbits with moderate hypercholesterolaemia by chronic inhibition of nitric oxide synthase (NOS).

EXPERIMENTAL APPROACH

White New Zealand rabbits were fed a 0.2% cholesterol diet with the NOS inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) in the same diet. Pitavastatin (0.1 and 0.3 mg x kg(-1)) was given orally once a day for 8 weeks. The aortic arch and thoracic aorta were analysed by histochemistry and atherosclerotic lesions were quantified. The effect of pitavastatin on adhesion of THP-1 cells to endothelial cells, and cholesterol content in RAW264.7 cells incubated with oxidized or acetylated LDL were also investigated.

KEY RESULTS

Atherosclerotic lesions containing foam cells were induced in a model of atherosclerosis in rabbits with moderate hypercholesterolaemia by chronic inhibition of NOS. The area of atherosclerotic lesions was diminished by pitavastatin administration. The adhesion of THP-1 cells and cholesteryl ester content in RAW macrophages were decreased by pitavastatin treatment.

CONCLUSION

Atherosclerosis induced by chronic inhibition of NOS in moderately hypercholesterolaemic rabbits was suppressed by pitavastatin via inhibition of macrophage accumulation and macrophage foam cell formation.

Casein-derived tripeptide, Val-Pro-Pro (VPP), modulates monocyte adhesion to vascular endothelium

AIM

A food-derived bioactive tripeptide, Val-Pro-Pro (VPP), has been shown to possess angiotensin I-converting enzyme (ACE) inhibitory activity and foods containing such peptides exhibit an anti-hypertensive effect in clinical settings.

METHODS

The present study focused on the effect of VPP on monocyte adhesion to endothelium under flow conditions using phorbol 12-myristate 13-acetate (PMA)-stimulated monocytic THP-1 cells.

RESULTS

Pre-incubation of THP-1 cells with VPP (1 mM, 24 hours) significantly decreased the PMA-induced adhesion of THP-1 cells (p<0.05) to human umbilical vein endothelial cells (HUVECs). PMA-induced up-regulation of beta1 and beta2 integrin activation in THP-1 cells was downregulated by VPP, which significantly suppressed only the PMA-induced phosphorylation of JNK (p<0.05) in THP-1 cells. In addition, preincubation of THP-1 with SP600125, a specific inhibitor of JNK, resulted in significant reduction of the PMA-induced adhesion of THP-1. Interestingly, another tripeptide with comparable ACE inhibitory activity, Leu-Gly-Pro (LGP), failed to reduce the PMA-induced adhesion of THP-1, suggesting a distinct anti-inflammatory effect of VPP on THP-1 adhesion.

CONCLUSION

These observations suggest that VPP moderates monocyte adhesion to inflamed endothelia via attenuation of the JNK pathway in monocytes, which might contribute to the primary prevention of atherosclerosis.

Cytoskeletal structure regulates endothelial cell immunogenicity independent of fluid shear stress

The cardiovascular disease atherosclerosis is directly linked to the functions of endothelial cells (ECs), which are affected by fluid shear stress (FSS). High, unidirectional FSS causes EC elongation with aligned cytoskeletal components and nonimmunogenic EC functions that protect against atherosclerosis. In contrast, low, oscillatory FSS is associated with cobblestone-shaped ECs with randomly oriented cytoskeletons and proinflammatory EC functions that promote atherosclerosis. Whether EC shape plays a role in EC immunogenic functions, independent of FSS, has not been previously determined. The goal of this study was to determine the effect of EC elongation and cytoskeletal alignment on the expression of inflammatory genes and functions. With the use of micropatterned lanes, EC elongation and cytoskeletal alignment were achieved in the absence of FSS. EC gene expression of key inflammation markers determined that the elongation and cytoskeletal alignment of micropattern-elongated ECs (MPECs) alone significantly downregulated VCAM-1 while having no effect on E-selectin and ICAM-1. The positive control of FSS-elongated ECs promoted E-selectin and VCAM-1 downregulation and upregulation of ICAM-1. Functionally, monocytic U937 cells formed weaker interactions on the surface of MPECs compared with cobblestone ECs. Interestingly, MPEC expression of the known FSS-dependent transcription factor krüppel-like factor 2 (KLF2), which promotes a nonimmunogenic EC phenotype, was significantly upregulated in MPECs compared with cobblestone ECs. Cytoskeletal regulation of KLF2 expression was shown to be dependent on microtubules. Therefore, the cellular elongation and cytoskeletal alignment of MPECs regulated immunogenic gene expression and functions and may act synergistically with FSS to create an EC surface with reduced inflammatory capability.

Pleiotropic vasoprotective effects of statins: the chicken or the egg?

Statins (3-hydroxy-3-methyl glutaryl coenzyme A [HMG-CoA] reductase inhibitors) are the most commonly used lipid-lowering drugs. Their main lipid-lowering effect is achieved by an increase in the expression of low-density lipoprotein cholesterol receptors associated with inhibition of cholesterol synthesis through inhibition of HMG-CoA reductase - the first and rate-limiting step in cholesterol synthesis. However, beyond cholesterol synthesis inhibition, inhibition of the HMG-CoA reductase affects as well the synthesis of other molecules with significant roles in different, yet often intercalating, metabolic pathways. On this basis, and supported by an increasing series of advocating epidemiological and experimental data, an extended dialogue has been established over the last few years regarding the nonlipid or "pleiotropic" actions of statins.

Polymorphisms of fractalkine receptor CX3CR1 gene in patients with symptomatic and asymptomatic carotid artery stenosis

AIM

The chemokine fractalikine is expressed in vascular endothelium, exerting a pro-atherogenic effect. Two single-nucleotide polymorphisms of the CX3CR1 gene (T280M and V249I) affect frac-talkine receptor expression and function. We aimed to assess the prevalence of CX3CR1 polymor-phisms and the association with ischemic cerebrovascular attacks in a cohort of carotid atheromatous disease patients and age-matched controls.

METHODS

Using PCR-RFLP, we analyzed allelotypes for T280M and V249I in 150 patients with and 151 controls without carotid atherosclerosis assessed using carotid duplex ultrasound; the subjects were patients admitted for any reason to a tertiary hospital. Genotype data were compared with modifiable risk factors for cerebrovascular disease and the reason for admission, using ischemic stroke as an endpoint. Stroke types associated with carotid atherosclerosis were analysed separately.

RESULTS

The M280 allelic frequency was lower among carotid atherosclerosis patients than controls (0.15 versus 0.23, adjusted OR 0.47, 95% CI 0.30-0.74). Absence of M280 allele was an indepen-dent factor associated with carotid atherosclerosis (OR 3.70, 95% CI 1.92-7.14), stronger than hypertension, dyslipidemia, diabetes and cigarette smoking. The I249 allele was also under-repre-sented in carotid atherosclerosis; this was not statistically significant. T280M and V249I genotypes were not associated with admission due to ischemic stroke of the large vessel subtype (TOAST classi-fication, 73 episodes), whereas carotid atherosclerosis, previous ischemic event, age, hypertension, diabetes, hyperlipidemia and cigarette smoking were all independently associated.

CONCLUSIONS

The M280 fractalkine receptor gene allele is associated with a lower risk of carotid ath-eromatous disease, independent from the modifiable cerebrovascular risk factors.

Toll-like receptor 2 mediates apolipoprotein CIII-induced monocyte activation

Apolipoprotein (apo)CIII predicts risk for coronary heart disease. We recently reported that apoCIII directly activates human monocytes. Recent evidence indicates that toll-like receptor (TLR)2 can contribute to atherogenesis through transduction of inflammatory signals. Here, we tested the hypothesis that apoCIII activates human monocytoid THP-1 cells through TLR2. ApoCIII induced the association of TLR2 with myeloid differentiation factor 88, activated nuclear factor (NF)-kappaB in THP-1 cells, and increased their adhesion to human umbilical vein endothelial cells (HUVECs). Anti-TLR2 blocking antibody, but not anti-TLR4 blocking antibody or isotype-matched IgG, inhibited these processes (P<0.05). ApoCIII bound with high affinity to human recombinant TLR2 protein and showed a significantly higher (P<0.05) and saturable binding to 293 cells overexpressing human TLR2 than to parental 293 cells with no endogenous TLR2. Overexpression of TLR2 in 293 cells augmented apoCIII-induced NF-kappaB activation and beta(1) integrin expression, processes inhibited by anti-apoCIII antibody as well as anti-TLR2 antibody. Exposure of peripheral blood monocytes isolated from C57BL/6 (wild-type) mice to apoCIII activated their NF-kappaB and increased their adhesiveness to HUVECs. In contrast, apoCIII did not activate monocytes from TLR2-deficient mice. Finally, intravenous administration to C57BL/6 mice of apoCIII-rich very-low-density lipoprotein (VLDL), but not of apoCIII-deficient VLDL, activated monocytes and increased their adhesiveness to HUVECs, processes attenuated by anti-TLR2 or anti-apoCIII antibody. ApoCIII-rich VLDL did not activate monocytes from TLR2-deficient mice. In conclusion, apoCIII activated monocytes at least partly through a TLR2-dependent pathway. The present study identifies a novel mechanism for proinflammatory and proatherogenic effects of apoCIII and a role for TLR2 in atherosclerosis induced by atherogenic lipoproteins.

Effect of Conventional and More Aggressive Rosuvastatin Treatment on Markers of Endothelial Activation

Treatment of hypercholesterolemia with HMG-CoA reductase inhibitors results in an earlier reduction of morbidity and mortality than expected from trials using conventional cholesterol-lowering therapies. Possible explanations for this effect include improvement of endothelial function, plaque stabilization, and inhibition of the inflammatory response associated with atherosclerosis. In this study we assessed the effects of low and moderate dose rosuvastatin treatment, on circulating markers of endothelial activation in patients admitted for acute coronary syndromes without ST segment elevation. Thirty patients with unstable angina and non ST segment elevation myocardial infarction were rando - mized into two groups, and received rosuvastatin 10 mg/day (n =16) or rosuvastatin 20 mg/day (n =14) for 12 weeks. Circulating levels of soluble vascular cell adhesion molecule (sVCAM-1) and intercellular adhesion molecule-1 (sICAM-1) were measured at admission, and at the end of the study. Lipid values were significantly reduced in both treatment groups, but with significantly greater reduction in the aggressively treated group. Serum levels of sICAM-1 and sVCAM-1 were significantly decreased in both rosuvastatin-treated groups during 12 weeks of follow-up with a more pronounced decrease in the more aggressively treated group. Therefore, rosuvastatin modulates endothelial activation in patients after acute coronary syndromes.

RhoA-GDP regulates RhoB protein stability. Potential involvement of RhoGDIalpha

RhoA plays a significant role in actin stress fibers formation. However, silencing RhoA alone or RhoA and RhoC did not completely suppress the stress fibers suggesting a residual "Rho-like" activity. RhoB, the third member of the Rho subclass, is a shortlived protein barely detectable in basal conditions. In various cell types, the silencing of RhoA induced a strong up-regulation of both total and active RhoB protein levels that were rescued by re-expressing RhoA and related to an enhanced half-life of the protein. The RhoA-dependent regulation of RhoB does not depend on the activity of RhoA but is mediated by its GDP-bound form. The stabilization of RhoB was not dependent on isoprenoid biosynthesis, Rho kinase, extracellular signal-regulated kinase, p38 mitogen-activated kinase, or phosphatidylinositol 3'-OH kinase pathways but required RhoGDIalpha. The forced expression of RhoGDIalpha increased RhoB half-life, whereas its knock-down antagonized the induction of RhoB following RhoA silencing. Moreover, a RhoA mutant (RhoAR68E) unable to bind RhoGDIalpha was significantly less efficient as compared with wild-type RhoA in reversing RhoB up-regulation upon RhoA silencing. These results suggest that, in basal conditions, RhoGDIalpha is rate-limiting and the suppression of RhoA makes it available to stabilize RhoB. Our results highlight RhoGDIalpha-dependent cross-talks that regulate the stability of RhoGTPases.

Statins and sepsis

Severe sepsis and septic shock is common and frequently fatal. Over the last few years, the primary treatments demonstrated to improve outcome from several major clinical trials have finally emerged. However, translating these recent therapeutic advances to routine clinical practice has proven controversial, and new approaches of additional strategies are continued to be developed. Given their pleiotropic effects related to many pathophysiological determinants of sepsis, statin therapy could be the next step in the search for adjuvant therapy. A future challenge may be to test both the efficacy and the safety by large randomized controlled clinical trials ascertaining the effects of statins administered at the onset of sepsis and in patients with severe sepsis or septic shock admitted into intensive care units.

Simvastatin treatment modifies polymorphonuclear leukocyte function in high-risk individuals: a longitudinal study

BACKGROUND

Although extensive experimental evidence supports a primary role of polymorphonuclear leukocytes (PMNs) in atherosclerosis, few data exist concerning the functional properties of these cells and their pharmacological modulation in high-risk individuals.

OBJECTIVE

The production of the proinflammatory chemokine interleukin-8 (IL-8), migration and chemotaxis, and reactive oxygen species (ROS) generation were investigated in a longitudinal study in PMNs obtained from high-risk individuals during statin treatment. As a secondary endpoint we compared PMN function of high-risk patients with that of controls.

METHODS AND RESULTS

PMNs were isolated from 21 high-risk individuals before treatment and 3 and 30 days after the beginning of simvastatin treatment, and from healthy controls. During treatment a significant reduction was observed both in resting (P = 0.009) and N-formyl-Met-Leu-Phe (fMLP)-stimulated (P = 0.008) IL-8 production, and in the chemotactic index (P = 0.038), whereas ROS generation did not significantly change. In comparison with cells from controls, PMNs obtained from patients before starting simvastatin treatment showed higher resting and fMLP-stimulated IL-8 release (P = 0.007 and P = 0.002, respectively) and ROS generation (resting, P = 0.009; and fMLP-stimulated, P = 0.046), whereas migration and the chemotactic index did not significantly differ.

CONCLUSIONS

An activation of neutrophils is present in high-risk individuals, shown by the enhanced production of IL-8, and increased ROS generation. The 4-week statin treatment is able to reduce the cell capability to produce IL-8, and to decrease chemotaxis, thus affecting the proinflammatory properties of PMNs.