Immunomodulatory effects of statins: mechanisms and potential impact on arteriosclerosis

Effect of atorvastatin on TH1 and TH2 cytokine secreting cells during T cell activation and differentiation

Statins, which are 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, are the most effective agents for the lowering of cholesterol in clinical practice. In addition to their lipid-lowering properties, statins also have immunomodulatory activities. Animal studies have shown that statins promote a T helper 2 (T(H)2) bias and suppress the secretion of T helper 1 (T(H)1) cytokines. We therefore examine whether atorvastatin modulates the T(H)1/T(H)2 responses in human T cells. Using primary T cells as well as differentiated T(H)1 and T(H)2 cells, the immunomodulatory effect of atorvastatin on cells secreting IFN-gamma (T(H)1 response) and IL-4 (T(H)2 response) was investigated. Atorvastatin had no effect on cells secreting IFN-gamma and IL-4 in primary T cells stimulated with anti-CD3 and -CD28 antibodies. Similarly, cells producing IFN-gamma and IL-4 in stable differentiated T(H)1 and T(H)2 cells were unaffected by atorvastatin. Furthermore, atorvastatin had no effect on the ratio of IFN-gamma+/IL-4+ cells during the differentiation of T(H)0 cells to T(H)1 and T(H)2 cells in long-term cultures. These data suggest that atorvastatin does not have any immunomodulatory effect on the T(H)1/T(H)2 balance in human T cells in vitro.

Effects of statins beyond lipid lowering: Potential for clinical benefits

BACKGROUND

The role of statin drugs in the reduction of serum lipids has been well documented. More recently, evidence suggesting that statins may positively impact many organ systems and disease states independent of lipid reduction has emerged. The term "pleiotropic effects" has been used to refer to these properties. We reviewed the evidence exploring such potential effects.

METHODS

A search of the MEDLINE database was conducted for articles published between 1985 to 2005 on the pleiotropic and the lipid-lowering independent effects of statin drugs. The search terms "statin", "HMG-CoA reductase inhibitor", "pleiotropic effects", and "inflammation" were used. English language articles were selected for inclusion along with selected cross-references.

RESULTS

Numerous animal and clinical studies support the presence of a spectrum of beneficial effects for statins that are independent of their lipid-lowering properties. These effects are mediated by a variety of mechanisms and they suggest that the therapeutic role of statins may expand.

CONCLUSION

Statins have shown great promise beyond their lipid-lowering effects. Ongoing and future studies will help to further clarify the potential clinical impact of these "pleiotropic effects".

Management of Dyslipidemia in Special Populations

Dyslipidemia is a significant contributor to morbidity and mortality in the industrialized world. Because it is often intertwined with other medical conditions, its management is becoming progressively more complex. Populations that pose a particular challenge to clinicians include diabetic patients, children and adolescents, elderly persons, transplant patients, patients with the human immunodeficiency virus, and patients with chronic kidney disease. When establishing lipid goals, it is imperative to have a thorough understanding of the evidence, or lack thereof, supporting the use of lipid-lowering agents among these patients. To maximize the benefits and minimize the risks of pharmacological intervention, clinicians must consider not only the unique alterations in the lipid profile of the aforementioned populations but also individual changes in patients' pharmacokinetic and pharmacodynamic parameters, as well as the potential for drug-drug and drug-disease interactions.

Atorvastatin affects interleukin-2 signaling by altering the lipid raft enrichment of the interleukin-2 receptor beta chain

Although the immunomodulatory properties of statins are in part independent of their lipid-lowering effects, cholesterol is a major component of lipid rafts. We therefore studied the effects of atorvastatin (AS) on the raft enrichment of the interleukin-2 receptor (IL-2R) beta chain previously described by us and on early IL-2R signaling events in activated human T cells. We found that concomitant AS exposure during a 3-day stimulation with phytohemagglutinin (PHA) attenuates activation-associated events, such as the enhanced surface expression of the raft marker GM-1 and the induced expression of the activation marker CD25 (the IL-2R alpha chain). In contrast, brief AS treatment after PHA stimulation increased GM-1 surface expression and virtually abolished the selective raft enrichment of the IL-2R beta chain. Although this AS-associated increase in GM-1 expression resembled that seen in the presence of the raft-disrupting cholesterol chelator methyl-beta-cyclodextrin (MBCD), the two agents had contrasting effects on the tyrosine phosphorylation of the IL-2R beta chain by exogenous IL-2: MBCD essentially abolished this event, whereas AS tended to enhance it and shifted its occurrence out of rafts. We conclude that AS affects IL-2R signaling by altering the raft enrichment of the IL-2R beta chain and propose that this effect is one mechanism underlying the immunomodulatory properties of statins.

Prospective monitoring of lipid profiles in children receiving pravastatin preemptively after renal transplantation

Hyperlipidemia is common after renal transplantation (Tx) and contributes to the increased cardiovascular morbidity seen in the post-transplant period. Limited data are available on the utility of the statins in children after renal Tx. This 12-month prospective study was undertaken to determine the efficacy of pravastatin in reducing dyslipidemia after renal Tx in children and to determine predictors of dyslipidemia after Tx. From August 2001 to April 2004, all 17 newly transplanted pediatric renal transplant recipients at our center were preemptively treated with pravastatin from the immediate post-transplant period. Fasting lipid profiles were obtained at 1, 3, 6 and 12 months after Tx. Trends in the lipid profile were analyzed using the repeated measures general linear model (GLM). A historical cohort of pediatric renal-transplant recipients not treated with pravastatin was used as the control population. The mixed effects GLM was used for multivariable logistic regression analyses to determine the independent effect of age, pretransplant cholesterol (Chol), body mass index (BMI), creatinine clearance (CrCl), and corticosteroid and tacrolimus doses on the development of dyslipidemia. The mean age of the children at Tx was 8.7 yr. The GLM analysis showed that with time, there was a significant decline in the total Chol, serum triglyceride (TG), LDL and also HDL-Chol (p-value <0.05 for each). Compared with the controls, the mean serum Chol was lower at all time points post-transplant in the treated patients. However, despite treatment, the prevalence of hypercholesterolemia increased from 31% pretransplant to 53% at 1-month, but declined thereafter to 6% at 3 and 6 months and 0% at 1 yr. Multivariable regression analyses showed the prednisone dose, pretransplant Chol and age to be the most important risk factors for the development of dyslipidemia. No child developed complications related to therapy. In summary, pravastatin is safe in the post-transplant period in children and reduces serum Chol, LDL-Chol and TG. An unexpected finding in our study was the decline in HDL-Chol after Tx. Whether the preemptive use of the statins will result in lower cardiovascular morbidity, especially considering the concomitant reduction in HDL-Chol remains to be determined.

The role of statins in chronic kidney disease

Chronic kidney disease is associated with cardiovascular event rates that are at least as high as in patients with established atherosclerotic cardiovascular disease or in those with diabetes mellitus. Chronic kidney disease is therefore considered a cardiovascular disease risk equivalent. Treatment of dyslipidemia, which is very common in this population and reflects the pattern seen in the metabolic syndrome, reduces cardiovascular events in patients with chronic kidney disease. Thus, patients with chronic kidney disease should be evaluated and treated for dyslipidemia. Dyslipidemia is a risk factor for the development of impaired kidney function. Dyslipidemia is also associated with progressive renal disease in subjects with no overt renal disease, as well as those with diabetic and nondiabetic kidney disease. Although definitive randomized controlled trials are lacking, the collective evidence suggests that treatment of dyslipidemia is associated with less decline in renal function. The use of potent statins in high doses can lead to transient proteinuria via impairment of proximal tubular receptor--mediated endocytosis, in a dose-dependent manner. Over the long term, however, the use of statins results in a reduction in proteinuria and in the rate of decline of renal function. Several large definitive trials that are currently underway to examine the safety and efficacy of statins in cardiovascular and renal protection should provide more definitive answers on the role of these drugs in this very high risk population.

Statin Therapy in Rheumatoid Arthritis

Rheumatoid arthritis, a chronic inflammatory polyarthritis that destroys synovial joints, is associated with systemic as well as local inflammation and with an increased risk of cardiovascular disease and death not fully explained by traditional cardiac risk factors. Statins (HMG-coA reductase inhibitors), medications originally designed to lower cholesterol, have been shown to have powerful effects on decreasing cardiovascular mortality rates in the general and high-risk populations. Not all of this protective benefit appears to be mediated by lowered cholesterol levels. Statins also influence multiple steps in the inflammatory process, including leukocyte migration and adhesion, T-cell stimulation, nitric oxide bioavailability, generation of free radicals, and angiogenesis. Recent studies show that statins may provide mild anti-inflammatory benefit in rheumatoid arthritis, in addition to reducing cardiovascular risk.

Are steroids alone sufficient for the treatment of giant cell arteritis?

Glucocorticosteroids are the cornerstone of treatment of giant cell arteritis. An initial dose of prednisone or its equivalent of at least 40-60mg per day as single or divided dose is usually adequate. Glucocorticosteroids may prevent, but usually do not reverse, visual loss. A treatment course of 1-2 years is often required. Some patients, however, have a more chronic-relapsing course and may require low doses of glucocorticosteroids for several years. Glucocorticosteroid-related adverse events are common. In studies on immunosuppressant agents, methotrexate has been used as a glucocorticosteroid-sparing drug with conflicting results. This drug may, however, be given to patients who need high doses of glucocorticosteroids to control active disease and who have serious side effects. A recent pilot study found that infliximab was efficacious in patients with glucocorticosteroid-resistant giant cell arteritis. However, randomized controlled trials are required to define the role of anti-tumor necrosis factor-alpha agents in the treatment of giant cell arteritis. Finally, low-dose aspirin has been shown in a recent retrospective study to decrease the rate of cranial ischemic complications secondary to giant cell arteritis. It is conceivable that the definition of different patterns of inflammation in giant cell arteritis in the future might facilitate the design of differentiated therapeutic approaches.

The "Statinth" wonder of the world: a panacea for all illnesses or a bubble about to burst

After the introduction of statins in the market as effective lipid lowering agents, they were shown to have effects other than lipid lowering. These actions were collectively referred to as 'pleiotropic actions of statins.' Pleiotropism of statins formed the basis for evaluating statins for several indications other than lipid lowering. Evidence both in favour and against is available for several of these indications. The current review attempts to critically summarise the available data for each of these indications.

Effect of Prior Statin Use on Functional Outcome and Delayed Vasospasm after Acute Aneurysmal Subarachnoid Hemorrhage: A Matched Controlled Cohort Study

OBJECTIVE

Hydroxymethylglutaryl coenzyme A reductase inhibitors (statins), which exhibit beneficial cerebrovascular effects by modulating inflammation and nitric oxide production, have not been evaluated in acute aneurysmal subarachnoid hemorrhage (SAH) patients. The effect of prior statin use on 14-day functional outcome and on prevention of vasospasm-induced delayed cerebral ischemia (DCI) or stroke during hospitalization was analyzed.

METHODS

We conducted a 1:2 matched (age, admission Hunt and Hess grade, vascular disease/risk history) cohort study of 20 SAH patients on statins and 40 SAH controls. The primary outcome was functional outcome at 14 days (Modified Lawton Physical Self-Maintenance Scale and Barthel Index scale scores). Secondary outcomes were 14-day mortality, Modified Rankin Scale score, DCI, DCI supported by angiography/transcranial Doppler [TCD], cerebral infarctions of any type, and TCD highest mean velocity elevation.

RESULTS

Statin users demonstrated a significant protective effect on 14-day Barthel Index scale and Modified Lawton Physical Self-Maintenance Scale scores (77 +/- 10 versus 39 +/- 8, P = 0.003; 12 +/- 7 versus 19 +/- 9, P = 0.03, respectively). Moreover, statin users demonstrated a significantly lower incidence of DCI and DCI supported by angiography/TCD (10% versus 43%, P = 0.02; 5% versus 35%, P = 0.01, respectively), cerebral infarctions of any type (25% versus 63%, P = 0.01), and baseline-to-final TCD highest mean velocity change of 50 cm/s or greater (18% versus 51%, P = 0.03).

CONCLUSION

SAH statin users demonstrated significant improvement in 14-day functional outcome, a significantly lower incidence of DCI and cerebral infarctions of any type, as well as prevention of TCD highest mean velocity elevation. However, we did not find a significant statin impact on mortality or global outcome (Modified Rankin Scale) in this small sample. This study provides clinical evidence for the potential therapeutic benefit of statins after acute SAH.

Developmental origins of aging in brain and blood vessels: an overview

Emerging evidence suggests a remarkable convergence of inflammatory mechanisms in the etiology of cardiovascular disease and Alzheimer disease. A broad set of NSAIDs and statins used to reduce the risk of vascular occlusion and to slow atherogensis may also be protective for Alzheimer disease. Elevated blood levels of C-reactive protein are risk factors for cardiovascular disease and possibly for Alzheimer disease. Monocyte-lineage cells are also fundamental to both conditions: in blood vessels, macrophages are important to atherogenesis for the accumulation of lipids (foam cells), whereas brain microglia show activation during aging and direct involvement in amyloid metabolism in the senile plaque. Genetic influences are recognized through the apoE4 allele, which is associated with hypercholesterolemia and is a risk factor in vascular events and Alzheimer disease, and is recognized for its proinflammatory profile. ApoE4 also accelerates Alzheimer disease pathogenesis in Down's syndrome and many other chronic neurodegenerative conditions, as is well-supported by animal models. Inflammatory changes are present at the earliest stages of vascular disease and Down's syndrome in human fetuses, and are also prominent early in Alzheimer disease. These findings give a basis for considering inflammatory processes early in life which can lead to fully fired pathogenesis of cardiovascular disease and possibly for Alzheimer disease.

Neurodegenerative diseases: insights into pathogenic mechanisms from atherosclerosis

Increasing evidence indicates that several pathogenic mechanisms promoting atherosclerosis are also involved in neurodegenerative diseases, and that insight into the factors determining the susceptibility to, and long-term progression of, atherosclerosis may be of interest for the evolution of diseases such as Alzheimer's. Furthermore, atherosclerosis of intracranial arteries or thromboembolic consequences of atherosclerotic extracranial arteries are responsible for most ischemic events in the brain. Age-related changes of cerebrovascular atherosclerosis, and atherosclerosis in general, may therefore be important for stroke and neurodegenerative diseases affecting the elderly. In the following, pathogenic mechanism involving increased lipid peroxidation, oxidative stress, inflammation and immune responses, and fetal programming will be discussed in the context of cerebrovascular disease and aging.

Statin-induced immunomodulatory effects on human T cells in vivo

Statins are widely used for treatment of hypercholesterolemia. Recent experimental studies revealed that these drugs also exert anti-inflammatory effects. The aim of this study was to assess immunomodulatory effects of statins in humans in vivo. Twenty-seven healthy volunteers were analyzed for serum cytokines and acute phase proteins, HLA-DR and CD38 expression on T cells and superantigen-mediated T cell activation ex vivo before and after 14 days of statin treatment. First, simvastatin 40 mg was compared to atorvastatin 20 mg. Second, two different doses of simvastatin (20 and 40 mg) were tested. Atorvastatin treatment led to a significant down-regulation of HLA-DR and the CD38 activation marker on peripheral T cells, whereas simvastatin up-regulated both of these molecules. In contrast, superantigen-mediated T cell activation was inhibited by simvastatin and enhanced by atorvastatin. No significant effect of statin treatment on inflammatory serum markers was detected. Thus, immunomodulatory effects of statins on human T cells are first demonstrated in vivo and are differentially induced by two different statins: atorvastatin led to a major histocompatibility class II (MHC II) antigens down-regulation and may therefore be investigated for treatment of chronic transplant rejection; simvastatin inhibited superantigen-mediated T cell activation, which might explain reduced mortality of simvastatin-treated patients with staphylococcal bacteremia.

Geranylgeraniol regulates negatively caspase-1 autoprocessing: implication in the Th1 response against Mycobacterium tuberculosis

Caspase-1 is a cysteine protease composed by two 20-kDa and two 10-kDa subunits that processes pro-IL-1beta and pro-IL-18 to their mature forms. This enzyme is present in cells as a latent zymogen that becomes active through a tightly regulated proteolytic cascade. Activation is initiated by the oligomerization of an adaptor molecule, or by the formation of a multiprotein complex named inflammasome. Negative regulation of caspase-1 activation is exerted by proteins that compete with the adaptor molecule or with the inflammasome formation. We previously reported that fluvastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, increases caspase-1 activity in PBMC. This effect was strengthened by Mycobacterium tuberculosis, rending an exacerbated IL-1beta, IL-18, and IFN-gamma production. Mevalonate, the product of 3-hydroxy-3-methylglutaryl coenzyme A reductase, is a precursor for both nonsterol isoprenoid and sterol formation. In this study, we studied the involvement of mevalonate derivatives in the regulation of caspase-1 activation. Inhibition of sterol formation by SKF-104976 or haloperidol had no effect on IL-1beta release. However, the isoprenoid geranylgeraniol prevented both caspase-1 activation and the exacerbated IL production induced by fluvastatin. This isoprenoid significantly reduced the release of IL-18 and IFN-gamma by PBMC treated with mycobacteria, even in the absence of fluvastatin. In correlation with the increased caspase-1 activity, fluvastatin stimulated the proforms cleavage, enhancing the formation of active subunit p10. Geranylgeraniol not only prevented this effect, but induced proforms accumulation. Present results suggest that, once the proteolytic cascade is initiated, geranylgeraniol may exert an additional negative regulation on caspase-1 cleavage process.

Fluvastatin and fluvastatin extended release: a clinical and safety profile

Cardiovascular diseases due to atherosclerosis are the leading causes of mortality in the Western world. Cholesterol-lowering therapy with 3-hydroxy-3-methylglutaryl coenzyme Areductase inhibitors (statins) has demonstrated a reduction in cardiovascular morbidity and mortality in diverse populations. Fluvastatin (Lescol, Novartis Pharmaceuticals) was the first totally synthetic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor on the market and has recently become available in an extended-release formulation (Lescol XL, Novartis Pharmaceuticals). Data from several clinical outcome trials have shown substantial benefits from fluvastatin treatment in diverse populations. Fluvastatin exists primarily in its acid form and as inactive metabolites in vivo, while active metabolites as well as the lactone form are only present in small amounts. The demonstration of the safe use of fluvastatin in a wide range of patients may be associated with the predominant acid form of the drug in vivo, as well as its predominant metabolism via the cytochrome P450 2C9 pathway.

Intérêt des statines en néphrologie

STATINS IN THE CASE OF CHRONIC RENAL DISEASE: Data of several large clinical trials in the general population demonstrated that hydroxymethyl glutaryl coenzyme A reductase inhibitors (statins) are effective in cardiovascular disease prevention with a relatively safe profile. Patients with chronic kidney disease (CKD) are at high risk for developing premature cardiovascular disease, so the benefits of statin therapy might be expected to be substantial in this population. Adjusted dose of statins to calcinurine inhibitors and renal function seem to exhibit a favorable risk/benefit ratio in CKD patients.

STUDY RESULTS

Statin use is CKD patients has been associated with a certain efficacy of cardiovascular disease prevention in several uncontrolled trials, and one randomized trial in renal transplant recipients. Several other large-scale randomized trials in CKD patients [4D (atorvastatin), AURORA (rosuvastatin) and SHARP (simvastatin/ezetimib) are currently underway. The results of these trials will permit evidence-based medicinal arguments justifying life-long clinical use of statins for cardiovascular prevention in CKD patients with progressive renal dysfunction, but data are inconclusive.

OTHER POSSIBLE EFFECTS

Clinically relevant plethoric effects associated with statin therapy in CKD patients might be restricted to the decrease of inflammation and oxidative stress.

Statins in solid organ transplantation: is there an immunosuppressive effect?

Cardiac allograft vasculopathy is one of the major causes of mortality late after heart transplantation. This disease process occurs to a lesser extent in patients with other donor organs; however, a long-term graft dysfunction is similarly described in kidney, liver and lung transplant recipients. There are multiple immune and nonimmune risk factors associated with this vasculopathic disease process, one of which includes hyperlipidemia. Use of lipid lowering agents, specifically HMG-CoA reductase inhibitors (statins) was initially reported to have possible immunosuppressive effects in a single center study of heart transplant recipients. This has not been observed in kidney transplant recipients; however, a large randomized trial demonstrated a significant cardiovascular risk reduction in fluvastatin-treated kidney transplant patients, outcome similar to the numerous nontransplant clinical trials of statins in atherosclerosis. In two recent in vitro studies, statins have been reported to repress induction of MHC-II by interferon-gamma and selectively block leukocyte function antigen-1, both of which decrease T-lymphocyte activation. In conclusion, statins appear to have outcome benefits in heart and kidney transplant patients; however, firm evidence for a clinical immunosuppressive effect is lacking. Further studies in humans will be needed to demonstrate this potential effect of statins. Overall, the outcome benefits of statins from the heart and kidney clinical studies provide a firm rationale to support the use of statins in organ transplantation.

Trial of Atorvastatin in Rheumatoid Arthritis (TARA): double-blind, randomised placebo-controlled trial

BACKGROUND

Rheumatoid arthritis is characterised by inflammatory synovitis, articular destruction, and accelerated atherogenesis. HMG-CoA (3-hydroxy-3-methylglutarylcoenzyme A) reductase inhibitors (statins) mediate clinically significant vascular risk reduction in patients without inflammatory disease and might have immunomodulatory function. We postulated that statins might reduce inflammatory factors in rheumatoid arthritis and modify surrogates for vascular risk.

METHODS

116 patients with rheumatoid arthritis were randomised in a double-blind placebo-controlled trial to receive 40 mg atorvastatin or placebo as an adjunct to existing disease-modifying antirheumatic drug therapy. Patients were followed up over 6 months and disease activity variables and circulating vascular risk factors were measured. Coprimary outcomes were change in disease activity score (DAS28) and proportion meeting EULAR (European League Against Rheumatism) response criteria. Analysis was by intention to treat.

FINDINGS

At 6 months, DAS28 improved significantly on atorvastatin (-0.5, 95% CI -0.75 to -0.25) compared with placebo (0.03, -0.23 to 0.28; difference between groups -0.52, 95% CI -0.87 to -0.17, p=0.004). DAS28 EULAR response was achieved in 18 of 58 (31%) patients allocated atorvastatin compared with six of 58 (10%) allocated placebo (odds ratio 3.9, 95% CI 1.42-10.72, p=0.006). C-reactive protein and erythrocyte sedimentation rate declined by 50% and 28%, respectively, relative to placebo (p<0.0001, p=0.005, respectively). Swollen joint count also fell (-2.69 vs -0.53; mean difference -2.16, 95% CI -3.67 to -0.64, p=0.0058). Adverse events occurred with similar frequency in patients allocated atorvastatin and placebo.

INTERPRETATION

These data show that statins can mediate modest but clinically apparent anti-inflammatory effects with modification of vascular risk factors in the context of high-grade autoimmune inflammation.

Insulin resistance syndrome in children

The insulin resistance syndrome (syndrome X, metabolic syndrome) has become the major health problem of our times. Associated obesity, dyslipidemia, atherosclerosis, hypertension, and type 2 diabetes conspire to shorten life spans, while hyperandrogenism with polycystic ovarian syndrome affect the quality of life and fertility of increasing numbers of women. Whereas a growing number of single genetic diseases affecting satiety or energy metabolism have been found to produce the clinical phenotype, strong familial occurrences, especially in racially prone groups such as those from the Indian subcontinent, or individuals of African, Hispanic, and American Indian descents, together with emerging genetic findings, are revealing the polygenetic nature of the syndrome. However, the strong lifestyle factors of excessive carbohydrate and fat consumption and lack of exercise are important keys to the phenotypic expression of the syndrome. The natural history includes small for gestational age birth weight, excessive weight gains during childhood, premature pubarche, an allergic diathesis, acanthosis nigricans, striae compounded by gynecomastia, hypertriglyceridemia, hepatic steatosis, premature atherosclerosis, hypertension, polycystic ovarian syndrome, and focal glomerulonephritis appearing increasingly through adolescence into adulthood. Type 2 diabetes, which develops because of an inherent and/or an acquired failure of an insulin compensatory response, is increasingly seen from early puberty onward, as is atheromatous disease leading to coronary heart disease and stroke. A predisposition to certain cancers and Alzheimer's disease is also now recognized. The looming tragedy from growing numbers of individuals affected by obesity/insulin resistance syndrome requires urgent public health approaches directed at their early identification and intervention during childhood. Such measures include educating the public on the topic, limiting the consumption of sucrose-containing drinks and foods with high carbohydrate and fat contents, and promoting exercise programs in our nation's homes and schools.

Positive pleiotropic effects of HMG-CoA reductase inhibitor on vitiligo

Background

HMG-CoA reductase inhibitors (statins) are commonly used in medicine to control blood lipid disorder. Large clinical trials have demonstrated that statins greatly reduces cardiovascular-related morbidity and mortality in patients with and without coronary artery disease. Also, the use of HMG-CoA reductase inhibitors has been reported to have immunosuppressive effects.

Case presentation

We describe an unusual case of regression of vitiligo in a patient treated with high dose simvastatin. The relation between simvastatin and regression of vitiligo in this case report may be related to the autoimmune pathophysiology of the disease.

Conclusion

This unexpected beneficial impact provides another scientific credence to the hypothesis that immune mechanisms play a role in the development of vitiligo and that the use of statins as immuno-modulator could be of use not only for treatment relative to organ transplant but in other pathologies such as vitiligo.

Statin therapy is associated with lower mortality among patients with severe heart failure

Experimental considerations suggest both potential harm and benefit from statin therapy in patients with severe heart failure. However, relations of statin therapy with clinical outcomes in severe heart failure are not well established. Using data from the Prospective Randomized Amlodipine Survival Evaluation (PRAISE) trial, we evaluated associations of statin therapy with total mortality among 1,153 patients with severe heart failure (ejection fraction <30% and New York Heart Association class IIIB or IV symptoms) of ischemic and nonischemic etiologies. Statin therapy was administered to 134 patients (12%) during the study period. Over a 1.3-year mean follow-up, there were 413 deaths (29 deaths/100 person-years). Adjusting for age, gender, diabetes, smoking, heart failure etiology, ejection fraction, and New York Heart Association class, statin therapy was associated with a 62% lower risk of death (hazard ratio 0.38, 95% confidence interval 0.23 to 0.65), or 1 fewer death/5 patients taking statin therapy for 1 year. This association was not greatly altered by additional adjustment for a variety of other patient characteristics, including serum cholesterol levels. After propensity score analyses, statin therapy was still associated with a 48% lower risk of death (hazard ratio 0.52, 95% confidence interval 0.30 to 0.89). Although this observational study does not prove causality, further investigation of potential benefits of statins in patients with severe heart failure appears warranted.

Role of nutrition for cardiovascular risk reduction in chronic kidney disease patients

Cardiovascular disease (CVD) is the major cause of death in end-stage renal disease (ESRD) patients. Uremic malnutrition and chronic inflammation are important comorbid conditions, closely associated with CVD risk in ESRD patients. A pathophysiologic link between uremic malnutrition, chronic inflammation, and atherosclerosis has been proposed in this patient population. Uremic malnutrition can result from chronic inflammation and can accelerate the progression of cardiovascular disease. Chronic inflammation can also directly predispose ESRD patients to a proatherogenic state. Both uremic malnutrition and chronic inflammation are also associated with increased oxidative stress, a condition proposed as a unifying concept of CVD in uremia. Although a single common etiology has not been identified in this complex process, nutritional, anti-inflammatory, and antioxidant interventions can provide potential treatment options to improve the high mortality and morbidity in ESRD patients.

Treatment with Fluvastatin Rapidly Modulates, via Different Pathways, and in Dependence on the Baseline Level, Inflammation in Hemodialysis Patients

BACKGROUND

Hemodialysis (HD) patients are frequently in an elevated inflammatory state which is correlated to the atherosclerosis-related and overall morbidity and mortality in this population. Statins, beyond their antilipidemic effects, are also considered to have anti-inflammatory, immunomodulating and antioxidant properties. The individual response of HD patients to a short course of fluvastatin, the mechanisms involved in the immunomodulating and anti-inflammatory effects of this drug and the time interval to the appearance of these effects are investigated in this longitudinal study.

METHODS

In a group of 51 HD patients, fluvastatin 40 mg/day was administered for 4 weeks. Serial measurements of the lipid profile, C-reactive protein (CRP), interleukin-6 (IL-6), soluble IL-6 receptor (sIL-6R), interleukin-10 (IL-10), and serum oxidized LDL (ox-LDL), were performed before, during, and after the treatment period.

RESULTS

Total cholesterol was significantly reduced after 14 days of treatment with fluvastatin (from mean +/- SD 216.7 +/- 34.3 to 179.2 +/- 42.3 mg/dl, p < 0.001). IL-6 and ox-LDL were reduced on day 28 (p < 0.001 and p < 0.01, respectively) and IL-10 was increased on day 14 (p = 0.05); CRP did not change significantly during the treatment period while sIL-6R was increased on day 28 of fluvastatin administration (p < 0.05). In a subgroup of patients with CRP, IL-6, sIL-6R, and ox-LDL baseline serum values > or = the median and IL-10 < or = the median, CRP was reduced on day 28 of fluvastatin treatment (p < 0.01), IL-6 and ox-LDL were reduced earlier, on day 14 (p = 0.05 and p < 0.05, respectively) while sIL-6R did not change significantly during the treatment period.

CONCLUSIONS

Treatment with fluvastatin rapidly modulates inflammation in HD patients. Enhancement of anti-inflammatory mechanisms and attenuation of the inflammatory and oxidative state contribute to this modulation. Patients in an elevated baseline inflammatory state respond more rapidly and effectively to the treatment. This immediate and multi-potent action of the statins could be clinically useful in acute atherosclerosis complications or in the treatment of chronic inflammation in HD patients.

Direct Anti-Inflammatory Mechanisms Contribute to Attenuation of Experimental Allograft Arteriosclerosis by Statins

BACKGROUND

Despite the development of effective immunosuppressive therapy, transplant graft arterial disease (GAD) remains the major limitation to long-term graft survival. The interplay between host inflammatory cells and donor vascular wall cells results in an intimal hyperplastic lesion, which leads to ischemia and graft failure. HMG-CoA reductase inhibitors (statins) reduce GAD in human cardiac allografts, although it is unclear whether this is secondary to cholesterol lowering or other mechanisms. This study tested the hypothesis that statins can suppress GAD by cholesterol-independent pathways.

METHODS AND RESULTS

We performed heterotopic murine cardiac transplants in total allogeneic or major histocompatibility complex class II-mismatched combinations. Transplanted animals received either control chow, chow containing 25 ppm cerivastatin (low dose), or chow containing 125 ppm cerivastatin (high dose). Mean plasma cerivastatin concentrations were 0.0 (control), 10.1 (low dose), and 21.9 (high dose) nmol/L, respectively. Plasma cholesterol levels were the same in all groups. GAD scores decreased in low-dose (P<0.05) and high-dose (P<0.0001) cerivastatin groups compared with controls, with concomitant reduction in graft-infiltrating cells and significantly decreased intragraft RANTES and monocyte chemotactic protein-1 mRNA expression. Cerivastatin, as well as other statins, also reduced RANTES and monocyte chemotactic protein-1 production in mouse endothelial cells stimulated with interferon-gamma and tumor necrosis factor-alpha in vitro.

CONCLUSIONS

Clinically achievable levels of an HMG-CoA reductase inhibitor attenuate GAD in murine heart transplants, diminish host inflammatory cell recruitment, and do not alter cholesterol levels. These results indicate that statins can affect arterial biology and inflammation independently of their effects on cholesterol metabolism.

Pilot study describing the use of pravastatin in pediatric renal transplant recipients

Renal transplant (Tx) recipients frequently develop hypercholesterolemia. Pravastatin (P) has been shown to be effective in adult renal Tx recipients, not only in reducing serum cholesterol, but possibly also in decreasing graft rejection. However, there are no data on the use of P in children following renal transplantation. We conducted a retrospective case-control study evaluating the safety and efficacy of P (10-20 mg/day) in reducing hypercholesterolemia, when used pre-emptively in the post-Tx period in seven children, compared with an historical control (C) group of nine children who had not received P. The two groups were comparable with respect to their demographics and in their pretransplant serum cholesterol. Compared with the C group, the mean serum cholesterol in the P group was lower at 3 months (159 mg/dL vs. 225 mg/dL), 6 months (134 mg/dL vs. 200 mg/dL), 9 months (134 mg/dL vs. 209 mg/dL), and 12 months (125 mg/dL vs. 195 mg/dL) (p < 0.005 for all, Student's two-tailed t-test). At 1 month only 43% of the P group had hypercholesterolemia compared with 67% of the controls; by 12 months this difference was even more significant (0% in the P group vs. 45% in the C group). None of the treated patients developed any adverse reactions. This study demonstrates that the pre-emptive use of P in pediatric renal Tx recipients appears to be effective in significantly reducing serum cholesterol. Whether this effect will translate into improved allograft and patient survival in the long term cannot be predicted at present and will require additional studies to evaluate.

Effect of a 3-year therapy with the 3-hydroxy-3-methylglutaryl coenzyme a reductase-inhibitor fluvastatin on endothelial function and distensibility of large arteries in hypercholesterolemic renal transplant recipient

BACKGROUND

In patients after renal transplantation functional arterial vessel wall properties are impaired. Whether 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors have a sustained effect on endothelial function and arterial distensibility in patients after renal transplantation is not clear. The authors studied the effects of a long-term therapy with fluvastatin on large artery distensibility and flow-mediated vasodilation (FMD) in hypercholesterolemic patients after renal transplantation in a prospective, blinded, and randomized trial.

METHODS

Twenty-six patients who had undergone renal transplantation were assigned randomly to either fluvastatin, 40 mg/d (n = 13) or placebo (n = 13) and underwent follow-up for 3 years. At baseline and after 6, 12, and 36 months of treatment, carotid and brachial artery distensibility, endothelium-dependent FMD, and nitroglycerine-induced vasodilation (NMD) of the brachial artery were measured by a echo-tracking device.

RESULTS

A significant decrease in total and low-density cholesterol was observed after 6, 12, and 36 months in patients treated with fluvastatin but not in the placebo group. FMD increased with fluvastatin from 4.6 +/- 2% to 12.4 +/- 2% after 12 months; this improvement was sustained with 13.4 +/- 3% after 36 months (P < 0.05). However, placebo did not alter FMD (P < 0.001 for trend difference between groups by analysis of covariance). Endothelium-independent NMD was similar in both groups at baseline and during therapy. Neither carotid nor brachial artery distensibility coefficients were altered by either treatment.

CONCLUSION

HMG-CoA reductase inhibitor therapy over 3 years results in a significant and sustained improvement of endothelial function in hypercholesterolemic patients after renal transplantation. However, this is not accompanied by a beneficial effect on impaired large artery distensibility even after long-term therapy with fluvastatin.