Immunomodulation: a new role for statins?

Effect of polyphenols against complications of COVID-19: current evidence and potential efficacy

The COVID-19 pandemic that started in 2019 and resulted in significant morbidity and mortality continues to be a significant global health challenge, characterized by inflammation, oxidative stress, and immune system dysfunction.. Developing therapies for preventing or treating COVID-19 remains an important goal for pharmacology and drug development research. Polyphenols are effective against various viral infections and can be extracted and isolated from plants without losing their therapeutic potential. Researchers have developed methods for separating and isolating polyphenols from complex matrices. Polyphenols are effective in treating common viral infections, including COVID-19, and can also boost immunity. Polyphenolic-based antiviral medications can mitigate SARS-CoV-2 enzymes vital to virus replication and infection. Individual polyphenolic triterpenoids, flavonoids, anthraquinonoids, and tannins may also inhibit the SARS-CoV-2 protease. Polyphenol pharmacophore structures identified to date can explain their action and lead to the design of novel anti-COVID-19 compounds. Polyphenol-containing mixtures offer the advantages of a well-recognized safety profile with few known severe side effects. However, studies to date are limited, and further animal studies and randomized controlled trials are needed in future studies. The purpose of this study was to review and present the latest findings on the therapeutic impact of plant-derived polyphenols on COVID-19 infection and its complications. Exploring alternative approaches to traditional therapies could aid in developing novel drugs and remedies against coronavirus infection.

Statin use and risk of severe bacterial infection in a population living with HIV: prospective cohort study of the ANRS CO3 Aquitaine Cohort 2000-2018

OBJECTIVES

Bacterial infections remain one of the main causes of morbidity and death in people living with HIV (PLHIV) in the most recent years. Several studies have demonstrated a protective effect of statins in the primary prevention of bacterial infections in other immunocompromised populations, but this effect remains controversial. The objective of this study was to evaluate the effect of statin use on the occurrence of a first episode of severe bacterial infection (SBI) in PLHIV in the ANRS CO3 Aquitaine cohort between 2000 and 2018.

METHODS

All individuals included in the prospective ANRS CO3 Aquitaine cohort who had at least two follow-up visits between 2000 and 2018 were included. The primary endpoint was the occurrence of a first episode of bacterial infection leading to hospitalization of ≥48 hours or death. Statin exposure was updated during follow-up. Marginal Cox structural models were developed to consider the potential indication bias and time-dependent confusion. Numerous sensitivity analyses were carried out.

RESULTS

In this study 51 658 person-years were followed. The overall incidence of a first episode of SBI was 12.4/1000 person-years. No effect of statins on the occurrence of SBI was demonstrated when subjects were considered on statins throughout their follow-up after treatment initiation (HR = 0.97; 95%CI: 0.75-1.25). The results were similar for the effect of statins on the risk of pneumonia and for all sensitivity analyses.

CONCLUSION

In this large cohort of PLHIV with 18 years of follow-up and a high risk of severe infections, we found no effect of statins on the risk of occurrence of SBI or pneumonia.

Novel human immunomodulatory T cell receptors and their double-edged potential in autoimmunity, cardiovascular disease and cancer

In the last decade, approaches based on T cells and their immunomodulatory receptors have emerged as a solid improvement in treatments for various types of cancer. However, the roles of these molecules in the therapeutic context of autoimmune and cardiovascular diseases are still relatively unexplored. Here, we review the best known and most commonly used immunomodulatory T cell receptors in clinical practice (PD-1 and CTLA-4), along with the rest of the receptors with known functions in animal models, which have great potential as modulators in human pathologies in the medium term. Among these other receptors is the receptor CD69, which has recently been described to be expressed in mouse and human T cells in autoimmune and cardiovascular diseases and cancer. However, inhibition of these receptors individually or in combination by drugs or monoclonal antibodies generates a loss of immunological tolerance and can trigger multiple autoimmune disorders in different organs and immune-related adverse effects. In the coming decades, knowledge on the functions of different immunomodulatory receptors will be pivotal for the development of new and better therapies with less harmful side effects. In this review, we discuss the roles of these receptors in the control of immunity from a perspective focused on therapeutic potential in not only cancer but also autoimmune diseases, such as systemic lupus erythematosus, autoimmune diabetes and rheumatoid arthritis, and cardiovascular diseases, such as atherosclerosis, acute myocardial infarction, and myocarditis.

The Impact of Statin Therapy on the Survival of Patients with Gastrointestinal Cancer

Statins are 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors that may play an important role in the evolution of cancers, due to their effects on cancer cell metabolism. Statins affect several potential pathways, including cell proliferation, angiogenesis, apoptosis and metastasis. The number of trials assessing the putative clinical benefits of statins in cancer is increasing. Currently, there are several trials listed on the global trial identifier website clinicaltrials.gov. Given the compelling evidence from these trials in a variety of clinical settings, there have been calls for a clinical trial of statins in the adjuvant gastrointestinal cancer setting. However, randomized controlled trials on specific cancer types in relation to statin use, as well as studies on populations without a clinical indication for using statins, have elucidated some potential underlying biological mechanisms, and the investigation of different statins is probably warranted. It would be useful for these trials to incorporate the assessment of tumour biomarkers predictive of statin response in their design. This review summarizes the recent preclinical and clinical studies that assess the application of statins in the treatment of gastrointestinal cancers with particular emphasize on their association with cancer risk.

Effect of statins in preventing hospitalizations for infections: A population study

PURPOSE

To investigate whether the hospitalization rate for bacterial infections was modified by statin therapy in a population retrospectively followed up, over years 2011 to 2015.

METHODS

By using administrative databases, the 5-year hospitalization rate due to bacterial infections in population living in Tuscany, Italy exposed to statin therapy (n = 52,049) was stratified by 5 prescribed daily doses classes (0%-20%, 20%-50%, 50%-80%, 80%-100%, ≥100% of DDD) and subsequently compared with that of a population of untreated individuals (n = 3 300 ,675), matched through a propensity score accounting for all available covariates potentially able to modulate risk of infections such as age, gender, previous hospitalizations for infections, cardiovascular events, previous co-morbidities, diabetes, as well as general practitioners' proactive behaviour of care delivery according to current guidelines.

RESULTS

Unmatched individuals of each treatment-class had significantly more hospitalizations than controls, while matched treated people, apart from those in class 0% to 20%, had a decrease of hospitalizations, as large as the increase in prescribed drug. Statin effect in reducing hospitalizations translated into a number needed to treat (NNT) ranging across treatment strata from 102 to 54.

CONCLUSIONS

Compliance to statin prescribed daily doses above the threshold 20% of DDD, along a 5-year follow-up, prevented hospitalizations due to infectious diseases in a large unselected population, after adjusting for covariates able to modulate baseline risk of infections. The NNTs to avoid 1 hospitalization for infections resulted on average not too dissimilar from a value lying between the 95% CI of NNTs previously found for primary prevention of 1 incident coronary ischemic event (72 to 119).

Effect of statins on hospitalization risk of bacterial infections in patients with or without diabetes

AIMS

To investigate whether statins reduce the risk to first hospitalization of bacterial infections, in patients with or without diabetes taking into account prior or incident comorbidities.

METHODS

By using administrative databases, the effect of current statin use was measured on the risk of first hospitalizations due to bacterial infections in people living in Tuscany, Italy, in the period January 1, 2011-December 31, 2015, after excluding those with previous statins use. Population was stratified as with (n = 128,207) or without diabetes (n = 3,304,906), and the hospitalization risk was analyzed by a Cox proportional hazards regression analysis after adjusting for age, gender, previous comorbidities, chronic renal failure, and prior or incident cardiovascular diseases.

RESULTS

During the 5-year follow-up, 31,543 hospitalizations for bacterial infections were observed: 2.08(2.06-2.10) per 1000 person-year in non-diabetic and 5679: 9.13(8.94-9.32) per 1000 person-year in diabetic population. Diabetes conferred a greater risk of hospitalizations, independently from confounders [adjusted HR (95% CI) 2.04 (1.97-2.10); P < 0.0001]. Statin use decreased the risk by about 2.5% for each one month of therapy, at the same extent in subjects with or without diabetes, after adjusting for all covariates.

CONCLUSIONS

In this population, diabetes was associated by a twofold increase in the 5-year risk of hospitalizations for bacterial infections. Statin use decreased this risk to a same extent in subjects without or with diabetes, after adjusting for main confounders including comorbidities, and previous or incident cardiovascular events.

Outcome of rheumatoid arthritis following adjunct statin therapy

Objective:

Rheumatoid arthritis (RA) is characterized by symmetric peripheral polyarthritis, inflammatory synovitis, and articular destruction. Statins, 3-hydroxy-3-methylglutaryl coenzyme A-reductase inhibitors, mediate significant vascular risk reduction in patients with coronary artery disease by promoting reduction in plasma levels of low-density-lipoprotein cholesterol. Extensive in vitro data, experimental studies and more recently few clinical trials have strongly suggested statins to possess an important role in RA mainly mediated by their anti-inflammatory and immunomodulatory properties. The objective of this study was to evaluate the effect of adjunct statin therapy in comparison to standard disease modifying antirheumatic drugs (DMARD) therapy in patients with RA.

Materials and Methods:

In this observational study, diagnosed RA patients of age group between 40 and 60 years were selected as per the inclusion criteria from the rheumatology outdoor. From the selected patients, we identified two separate groups of patients. Group 1 included 30 patients of RA currently under DMARD therapy with adjunct statin medication. Group 2 included 30 patients of RA currently under DMARD therapy. Patients were followed up over 6 months. Standard parameters such as disease activity score (DAS28), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) were recorded for comparing the outcome of RA in both groups.

Results:

Out of a total of 60 patients who took part in the study, significant beneficial role of adjunct statin medication was found in this study when prescribed along with conventional DMARDs in active RA patients. The mean DAS28, considered by far as the most important index of clinical disease activity in RA, was found to be significantly lower (P < 0.05) in the adjunct statin-treated group (group 1) than that of the conventional DMARD treated group (group 2) after 6 months of continuous therapy. Other two important biochemical markers of RA disease activity, that is, ESR and CRP were also found to be significantly lower (P < 0.05) in RA patients who were on adjunct statin medication (group 1) than in group 2 comprising RA patients only under conventional DMARDs therapy without statin medication.

Conclusion:

The results suggest an adjunct and potentially beneficial role of statin therapy in active cases of RA, producing significant clinical and biochemical improvement.

Effect of statin therapy on mortality in patients with infective endocarditis

The aim of our study was to determine whether pre-emptive statin therapy was associated with improved outcome of infective endocarditis (IE). We conducted a nationwide, population-based, propensity score-matched cohort study with the Taiwan's National Health Insurance Research Database. All patients with IE between January 2000 and December 2010 were enrolled. The primary outcome was in-hospital mortality. The secondary outcome included all-cause mortality within the first 3 months, 6 months, and one year after the diagnosis of IE. Among 13,584 patients with IE, we applied propensity score-matching on a 1:4 ratio, in which 370 statin users were matched to 1,480 statin non-users. Compared with statin non-users, statin users had a significantly lower risk of in-hospital mortality (adjusted hazard ratio [aHR] 0.65, 95% confidence interval [CI], 0.49-0.86). The reduction in mortality from IE remained significant for follow-up 3 months (aHR 0.68, 95% CI, 0.53-0.88), 6 months (aHR 0.73, 95% CI, 0.58-0.91), and 12 months (aHR 0.68, 95% CI, 0.55-0.84). Statin therapy was associated with a reduced risk of ICU admission rates, shock events, the need for mechanical ventilation, but not significantly with the need for heart valvular replacement surgery. In conclusion, our study found that statin therapy is associated with a reduced risk of in-hospital and subsequent mortality of IE.

Determination of Cell Death Induced by Lovastatin on Human Colon Cell Line HT29 Using the Comet Assay

Background

Apoptosis or programmed cell death is an essential process for elimination of damaged cells. Also, induction of apoptosis is fundamental for treating cancer. Screening for agents that induce apoptosis in tumor cells help in the development of novel agents for cancer treatment. Numerous studies suggest that the exposure of tumor cells to statins can lead to cell death via two separate processes: apoptosis or necrosis. Severe fragmentation of DNA during apoptosis can be readily measured by the neutral comet assay. Migration of DNA fragments of apoptotic cells by the electrical field can produce comet-like images.

Objectives

The aim of this study was to determine the type of cell death induced by lovastatin on human colon tumor cells by using the neutral comet assay and to evaluate the utility of this method for detection of apoptosis.

Materials and Methods

HT29 cells were grown in DMEM medium then exposed to different concentrations of lovastatin, and DNA fragmentation associated with apoptosis was detected by the neutral comet assay method.

Results

Lovastatin induced an apoptotic response in the HT29 cell line and produced a comet pattern similar to the positive control.

Conclusions

This study showed that lovastatin can induce apoptosis in the HT29 cell line and confirmed the utility of comet assay for detection of apoptosis.

Open-label phase 1b pilot study to assess the antiviral efficacy of simvastatin combined with sertraline in chronic hepatitis C patients

BACKGROUND

3-Hydroxy-3-methyl-glutaryl coenzyme A reductase inhibitors inhibit HCV replication in vitro. The combination of sertraline and simvastatin has synergistic antiviral activity in vitro, but there are no prior in vivo studies. Our aims were to prospectively assess the antiviral efficacy and safety of this drug combination in chronic hepatitis C (CHC) patients.

METHODS

A total of 15 CHC adults (including 1 control subject) that were treatment-naive or prior partial responders/relapsers to standard-of-care therapy were enrolled at four centres (2 in Singapore and 2 in the US). Patients received simvastatin 40 mg once daily and sertraline 50 mg once daily for 7 days, and then 80 mg once daily and 100 mg once daily, respectively, for another 21 days with a 14-day follow-up.

RESULTS

Of the 15 CHC patients, 13 completed the study. Subjects were mostly Caucasian (8/15), mean age 49.1 ±9 years and the genotype distribution was 1=10, 2=2 and 3=3. No subject discontinued dosing due to adverse events. Mean HCV RNA change from baseline was from -0.005 to -0.236 log(10) IU/ml across study intervals. Three subjects had transient >1 log(10) HCV RNA declines. No subject achieved >2 log(10) HCV RNA decline.

CONCLUSIONS

The combination of sertraline and simvastatin is well-tolerated over the short-term, but has no significant antiviral or anti-inflammatory response in CHC patients. This may reflect in vivo differences in synergy between statin and/or selective serotonin reuptake inhibitors and incomplete inhibition of membrane protein prenylation with statin therapy.

Changes in Adenosine Deaminase Activity in Patients with Type 2 Diabetes Mellitus and Effect of DPP-4 Inhibitor Treatment on ADA Activity

BACKGROUND

Dipeptidyl peptidase 4 (DPP-4, also known as CD26) binds with adenosine deaminase (ADA) to activate T lymphocytes. Here, we investigated whether ADA activity is specifically affected by treatment with DPP-4 inhibitor (DPP4I) compared with other anti-diabetic agents.

METHODS

Fasting ADA activity, in addition to various metabolic and biochemical parameters, were measured in 262 type 2 diabetes mellitus (T2DM) patients taking various anti-diabetic agents and in 46 non-diabetic control subjects.

RESULTS

ADA activity was increased in T2DM patients compared with that in non-diabetic control subjects (mean±standard error, 23.1±0.6 U/L vs. 18.6±0.8 U/L; P<0.05). ADA activity was correlated with fasting plasma glucose (r=0.258, P<0.05), HbA1c (r=0.208, P<0.05), aspartate aminotransferase (r=0.325, P<0.05), and alanine aminotransferase (r=0.248, P<0.05). Compared with the well-controlled T2DM patients (HbA1c<7%), the poorly controlled group (HbA1c>9%) showed significantly increased ADA activity (21.1±0.8 U/L vs. 25.4±1.6 U/L; P<0.05). The effect of DPP4I on ADA activity in T2DM patients did not differ from those of other oral anti-diabetic agents or insulin. T2DM patients on metformin monotherapy showed a lower ADA activity (20.9±1.0 U/L vs. 28.1±2.8 U/L; P<0.05) compared with that of those on sulfonylurea monotherapy.

CONCLUSION

Our results show that ADA activity is increased in T2DM patients compared to that in non-diabetic patients, is positively correlated with blood glucose level, and that DPP4I has no additional specific effect on ADA activity, except for a glycemic control- or HbA1c-dependent effect.

The effect of statin therapy on allergic patients with asthma

BACKGROUND

3-Hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors have significantly improved outcomes in coronary artery disease. They have anti-inflammatory and cholesterol-lowering effects. Statins alter the production of T(H)1 cytokines and thus promote a T(H)2 response. This immune alteration would promote allergic diseases such as asthma.

OBJECTIVE

To ascertain whether statin use adversely affects the clinical course of asthma.

METHODS

We retrospectively reviewed 759 medical records of consecutive patients with asthma to identify patients with extrinsic asthma who had at least 4 physician visits over 1 year. We compared patients who started receiving statins after their initial asthma evaluation with patients who never received statins. Baseline characteristics; change in forced expiratory volume in 1 second from baseline at 3, 6, 12, and 24 months; and a need for increases in medication and acute asthma visits were compared between the statin and control groups.

RESULTS

We identified 24 patients who started statin therapy and 26 control patients. There was a statistically significant 3% to 5% median worsening of forced expiratory volume in 1 second at all time points for the statin group compared with the controls. At 6 months, more patients in the statin group needed increased maintenance medication (16 [67%] vs 7 [27%]; P = .005), used albuterol more frequently (18 [75%] vs 3 [12%]; P < .001), had more nocturnal awakenings (8 [33%] vs 0 [0%]; P < .001), and were seen more frequently at office visits for acute asthma (9 [38%] vs 1 [4%]; P = .003).

CONCLUSIONS

This preliminary study demonstrated that patients with asthma who received statins had a worse clinical course than controls. Given the prevalence of both statin use and asthma, further research is needed.

Fluvastatin as an adjuvant to pegylated interferon and ribavirin in HIV/hepatitis C virus genotype 1 co-infected patients: an open-label randomized controlled study

OBJECTIVES

Recent reports demonstrated in vitro the efficacy of fluvastatin in inhibiting hepatitis C virus (HCV) replication and a synergistic effect in association with interferon-alpha (IFN-alpha). In vivo the inhibition of HCV replication by statins has not been demonstrated. We evaluated in this open-label, randomized controlled study the efficacy of fluvastatin as adjuvant to pegylated-(PEG)-IFN and ribavirin in HIV/HCV genotype 1 co-infected patients.

PATIENTS AND METHODS

Forty-four HIV/HCV co-infected patients were randomized to receive, in addition to PEG-IFN-alpha 2b and ribavirin, 80 mg of fluvastatin once daily or no medication. Primary and secondary endpoints were the achievement of sustained virological response (SVR) and rapid virological response (RVR), respectively.

RESULTS

By intent-to-treat analysis, 25% of the patients achieved an SVR. An SVR was observed in 8/21 patients in the fluvastatin arm and in 3/23 patients in the standard therapy arm (P = 0.08). A significantly higher RVR rate was obtained in the fluvastatin arm compared with the standard therapy [7/21 (33%) and 1/23 (4%), respectively; P = 0.02]. Baseline alanine aminotransferase (ALT) values and fluvastatin treatment arm were the only predictors of RVR at the univariate analysis; however, no predictors were independently associated with RVR or SVR at the multivariate analysis.

CONCLUSIONS

Fluvastatin addition to standard therapy did not significantly increase the SVR rate in HIV/HCV genotype 1 co-infected patients; however, it did significantly improve the RVR. Further studies are needed to confirm these promising results and to investigate the mechanisms of action of statins in HCV infection.

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.

The pathogenesis and treatment of chronic allograft nephropathy

Despite improvements in immunosuppressive therapy, long-term allograft survival after kidney transplantation remains as low as 50%. Chronic allograft nephropathy (CAN) is a major cause of late graft loss in renal transplant recipients. The histopathologic signs of CAN-interstitial fibrosis, tubular atrophy, glomerulopathy and vasculopathy-are nonspecific; therefore, the 2007 Banff classification dispensed with the term CAN in favor of 'interstitial fibrosis and tubular atrophy without evidence of any specific etiology'. In this Review, however, the term CAN is used to describe a clinical syndrome that is characterized by progressive decline in renal function from 3 months after transplantation, accompanied by the development of proteinuria and hypertension. The pathogenesis of CAN is complex and incompletely understood, and involves several immunological and non-immunological factors. We discuss the contributory roles of acute rejection, donor age, anti-human-leukocyte-antigen antibodies, calcineurin inhibitor nephrotoxic effects, viral infection, hypertension and hyperlipidemia. The prevention and treatment of CAN needs multidisciplinary strategies. Early detection by means of protocol biopsy and calculation of glomerular filtration rate is the first step, followed by management of modifiable risk factors.

Does fluvastatin favour HCV replication in vivo? A pilot study on HIV-HCV coinfected patients

Fluvastatin showed anti-hepatitis C virus (HCV) activity in vitro, through the inhibition of geranylgeranylation of cellular proteins, and a synergistic effect with interferon (IFN)-alpha. Nevertheless statins up-regulate low-density lipoprotein (LDL) receptor, required for HCV cell entry, and the closely related scavenger receptors SRBI and CD36; moreover they reduce class II major histocompatibility complex expression on antigen presenting cell, modulating T-cell activation. In vivo LDL levels have been identified as prognostic indicator of sustained viral response to IFN in patients with HCV infection, suggesting that lipid-lowering agents might conversely favour HCV entry into the hepatocytes and translate into higher viral replication. We evaluated the effect of fluvastatin on HCV-RNA levels, CD36 expression and T-cell homeostasis in HCV-RNA positive patients. HCV-RNA was measured at baseline and after 4 weeks in 42 HCV/HIV-1 co-infected patients, randomized to receive either fluvastatin 80 mg qd or no treatment. CD36 expression and markers of T-cell activation were evaluated by means of flow cytometry. Plasma interleukin (IL)-10, IFN-gamma and IL-7 were measured by ELISA. Serum cholesterol and LDL decreased significantly in the treatment group (P = 0.0001 and 0.01, respectively). Surprisingly a significant increase of HCV-RNA levels was seen after 4 weeks of fluvastatin (P = 0.03). The percentages of naive/activated/apoptotic cells and CD36 expression remained unchanged. Fluvastatin did not inhibit HCV-RNA replication in vivo; conversely we observed a significant increase of HCV-RNA levels. CD36 expression on monocytes were not up-regulated by statins as previously reported in vitro. The correlation between HCV infectivity, oxidized-LDL receptor and statins in HCV infection need further evaluation.

Simvastatin inhibits acidic extracellular pH-activated, outward rectifying chloride currents in RAW264.7 monocytic-macrophage and human peripheral monocytes

Extracellular acidic pH activated chloride channels (I(Cl,acid)) have been characterized in HEK 293 cells and mammalian cardiac myocytes. This study was designed to evaluate the expression of I(Cl,acid) in RAW264.7 monocytic-macrophage and human peripheral monocytes and to investigate the effect of simvastatin on I(Cl,acid). In two kinds of cells, the activation and deactivation of the current rapidly and repeatedly followed the change of the extracellular solution to pH=4.3. Compared with the outward current (pA/pF) activated at pH 4.3, the currents inhibited by simvastatin at concentrations of 0.1 microM were all decreased a little, however the currents at concentrations of 1 microM and 10 microM simvastatin were decreased significantly. The IC(50) for simvastatin inhibiting I(Cl,acid) of RAW264.7 was 13.77 microM. In summary, we report for the first time that simvastatin inhibits the I(Cl,acid) of RAW264.7 monocytic-macrophage and human peripheral monocytes in a concentration-dependent manner.

Solubility of lovastatin in a family of six alcohols: Ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, and 1-octanol

Accurate experimental determination of solubility of active pharmaceutical ingredients (APIs) in solvents and its correlation, for solubility prediction, is essential for rapid design and optimization of isolation, purification, and formulation processes in the pharmaceutical industry. An efficient material-conserving analytical method, with in-line reversed HPLC separation protocol, has been developed to measure equilibrium solubility of lovastatin in ethanol, 1-propanol, 1-butanol, 1-pentanol, 1-hexanol, and 1-octanol between 279 and 313K. Fusion enthalpy DeltaH(fus), melting point temperature, Tm, and the differential molar heat capacity, DeltaC(P), were determined by differential scanning calorimetry (DSC) to be 43,136J/mol, 445.5K, and 255J/(molK), respectively. In order to use the regular solution equation, simplified assumptions have been made concerning DeltaC(P), specifically, DeltaC(P)=0, or DeltaC(P)=DeltaS. In this study, we examined the extent to which these assumptions influence the magnitude of the ideal solubility of lovastatin, and determined that both assumptions underestimate the ideal solubility of lovastatin. The solubility data was used with the calculated ideal solubility to obtain activity coefficients, which were then fitted to the van't Hoff-like regular solution equation. Examination of the plots indicated that both assumptions give erroneous excess enthalpy of solution, H(infinity), and hence thermodynamically inconsistent activity coefficients. The order of increasing ideality, or solubility of lovastatin was butanol>1-propanol>1-pentanol>1-hexanol>1-octanol.

Lupus erythematosus and other autoimmune diseases related to statin therapy: a systematic review

BACKGROUND

Statins have been increasingly associated with drug-induced autoimmune reactions, including lupus erythematosus.

OBJECTIVE

To identify and determine the clinical and biological characteristics of statin-induced autoimmune reactions.

MATERIAL AND METHODS

The MEDLINE database (1966 to September 2005) was used to identify all reported cases of statin-induced autoimmune diseases. The keywords used were statins, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, adverse effects, autoimmune disease, lupus erythematosus, dermatomyositis and polymyositis.

RESULTS

Twenty-eight cases of statin-induced autoimmune diseases have been published so far. Systemic lupus erythematosus was reported in 10 cases, subacute cutaneous lupus erythematosus in three cases, dermatomyositis and polymyositis in 14 cases and lichen planus pemphigoides in one case. Autoimmune hepatitis was observed in two patients with systemic lupus erythematosus. The mean time of exposure before disease onset was 12.8+/-18 months; range 1 month-6 years. Systemic immunosuppressive therapy was required in the majority of cases. In many patients, antinuclear antibodies were still positive many months after clinical recovery. A lethal outcome has been recorded in two patients despite aggressive immunosuppressive therapy.

CONCLUSION

Long-term exposure to statins may be associated with drug-induced lupus erythematosus and other autoimmune disorders. Fatal cases have been reported despite early drug discontinuation and aggressive systemic immunosuppressive therapy.

Endothelial dysfunction: a comprehensive appraisal

The endothelium is a thin monocelular layer that covers all the inner surface of the blood vessels, separating the circulating blood from the tissues. It is not an inactive organ, quite the opposite. It works as a receptor-efector organ and responds to each physical or chemical stimulus with the release of the correct substance with which it may maintain vasomotor balance and vascular-tissue homeostasis. It has the property of producing, independently, both agonistic and antagonistic substances that help to keep homeostasis and its function is not only autocrine, but also paracrine and endocrine. In this way it modulates the vascular smooth muscle cells producing relaxation or contraction, and therefore vasodilatation or vasoconstriction. The endothelium regulating homeostasis by controlling the production of prothrombotic and antithrombotic components, and fibrynolitics and antifibrynolitics. Also intervenes in cell proliferation and migration, in leukocyte adhesion and activation and in immunological and inflammatory processes. Cardiovascular risk factors cause oxidative stress that alters the endothelial cells capacity and leads to the so called endothelial "dysfunction" reducing its capacity to maintain homeostasis and leads to the development of pathological inflammatory processes and vascular disease.

There are different techniques to evaluate the endothelium functional capacity, that depend on the amount of NO produced and the vasodilatation effect. The percentage of vasodilatation with respect to the basal value represents the endothelial functional capacity. Taking into account that shear stress is one of the most important stimulants for the synthesis and release of NO, the non-invasive technique most often used is the transient flow-modulate "endothelium-dependent" post-ischemic vasodilatation, performed on conductance arteries such as the brachial, radial or femoral arteries. This vasodilatation is compared with the vasodilatation produced by drugs that are NO donors, such as nitroglycerine, called "endothelium independent". The vasodilatation is quantified by measuring the arterial diameter with high resolution ultrasonography. Laser-Doppler techniques are now starting to be used that also consider tissue perfusion.

There is so much proof about endothelial dysfunction that it is reasonable to believe that there is diagnostic and prognostic value in its evaluation for the late outcome. There is no doubt that endothelial dysfunction contributes to the initiation and progression of atherosclerotic disease and could be considered an independent vascular risk factor. Although prolonged randomized clinical trials are needed for unequivocal evidence, the data already obtained allows the methods of evaluation of endothelial dysfunction to be considered useful in clinical practice and have overcome the experimental step, being non-invasive increases its value making it use full for follow-up of the progression of the disease and the effects of different treatments.

Effects of simvastatin in abdominal sepsis in rats

PURPOSE: Statins are widely recognized as hypolipemic drugs, but some studies have observed anti-inflammatory and immunomodulatory effects, known as pleiotropic. The aims of this work was to study possible anti-inflammatory effects of simvastatin in abdominal sepsis. Serum pro-inflammatory cytokines and leukocytes count were determined in an experimental model of abdominal sepsis, using cecal ligation and puncture (CLP) in rats. METHODS: Twenty eigth Wistar rats weighing 285±12g were randomly divided in: CLP/Sinvastatin rats (n=7), treated with 10 mg/Kg of oral simvastatin 18 and 2 hs berofe CLP; CLP/Saline group rats (n=7), treated with oral saline; group Sham/Simvastatin (n=7), treated with simvastatin, and group Sham/Saline (n=7), treated with saline. Serum TNF-alpha, IL-1beta and IL-6 by ELISA and total leukocytes, neutrophils, lymphocytes, and eosinophils were determined 24 hs after CLP. ANOVA and Tukey test were used considering significant p<0.05. RESULTS: It was demonstrated that serum TNF-alpha, IL-1beta and IL-6 were respectively 364,8±42pg/mL; 46,3±18pg/mL and 28,4±13pg/mL in CLP/Sinvastatin rats, significantly lower (p<0.05) than in group CLP/Saline (778,5±86pg/ml; 176,9±46pg/ml; 133,6±21 pg/ml, respectively). The same results were observed in total leukocytes and neutrophils counts. CONCLUSION: These results clearly demonstrate that simvastatin is an effective agent that reduces cytokines levels and leukocyte count in sepsis, independently of its well-known lipid-lowering effects. Thus, HMG-CoA reductase inhibitors like simvastatin have important anti-inflammatory effects in abdominal sepsis in rats.

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.

Statins and stroke

Inhibitors of HMG-CoA reductase (statins) are potent cholesterol-lowering drugs. Large clinical trials have shown that statins reduce the incidence of cerebrovascular events, which might be surprising because cholesterol is not an established risk factor for stroke. In addition to their cholesterol-lowering properties, statins exert a number of pleiotropic, vasculoprotective actions that include improvement of endothelial function, increased nitric oxide (NO) bioavailability, antioxidant properties, inhibition of inflammatory responses, immunomodulatory actions, regulation of progenitor cells, and stabilization of atherosclerotic plaques. In fact, statins augment cerebral blood flow and confer significant protection in animal models of stroke partly via mechanisms related to the upregulation of endothelial nitric oxide synthase. Retrospective clinical evidence suggests that long-term statin administration may not only reduce stroke risk but also improve outcome. Early secondary prevention trials are underway to test the hypothesis that statin treatment initiated immediately after an event improves short-term outcome. Lastly, recent evidence suggests that sudden discontinuation of statin treatment leads to a rebound effect with downregulation of NO production. Withdrawal of statin treatment may impair vascular function and increase morbidity and mortality in patients with vascular disease.

Statins Could Be Used to Control Replication of Some Viruses, Including HIV-1

Statins are mainly known for their plasma cholesterol-lowering properties and are widely used for the prevention of cardiovascular diseases. They however also exert pleiotropic effects through a variety of mechanisms, among which several immunosuppressive effects that are unrelated to their cholesterol-lowering activity. Interestingly, there has been recent evidence of antiviral effects, including preliminary studies on the efficacy of statins against HIV-1. This paper more particularly focuses on the specific inhibition of the binding of leukocyte function-associated antigen-1 (LFA-1) to intercellular adhesion molecule (ICAM-1) by statins, independently of the inhibition of HMGCoA reductase. Targeting the statin-binding site within LFA-1 or regulating LFA-1 affinity by inhibiting prenylation of the small GTPases could prove useful to treat inflammatory, autoimmune diseases and possibly viral infections, including HIV-1.

The effects of atorvastatin in experimental autoimmune uveitis

AIM

To investigate the effect of atorvastatin (Lipitor), a commonly used drug for dyslipidaemia in experimental autoimmune uveitis (EAU).

METHODS

48 B10-RIII mice were immunised with human interphotoreceptor retinoid binding protein (IRBP) peptide p161-180. They were divided into three groups of 16 each and treated orally once daily for 14 days; group one received phosphate buffered saline (control group), group two received 1 mg/kg of atorvastatin (low dose group), and group three received 10 mg/kg (high dose). On day 14 lymph nodes, spleens, and right eyes were harvested. RNA was extracted from lymph nodes for RNase protection assay (RPA) to determine proinflammatory (IL-1 alpha and IL-1 beta), Th1 (TNF-alpha, IL-2, IL-12), and Th2 (IL-4, IL-5, and IL-10) cytokine levels. Protein was extracted from spleens for western blot to detect the expression of phosphorylated signal transducer and activator of transcription (STAT) 4 and STAT6. The severity of inflammation in enucleated eyes was graded by a masked observer. Paired t test was performed for the mean difference in histological scoring between treated groups and the immunised control group.

RESULTS

Surprisingly, atorvastatin did not modulate the immune response. The proinflammatory cytokines, IL-1 alpha and IL-1 beta, and Th1 cytokines, TNF-alpha and IL-2, were upregulated equally in control and atorvastatin treated groups. IL-12 and Th2 cytokines were not upregulated in all three groups. Western blot analysis showed high levels of phosphorylated STAT4, but not STAT6 protein in the control and atorvastatin treated groups. Mean differences in histological scoring between treated groups and the immunised control group were not statistically significant.

CONCLUSIONS

Atorvastatin treatment had no effect on Th1 and Th2 cytokine transcription. Although histological grading suggested mildly decreased inflammation in the high dose treated group, the equivalence of cytokine expression in all groups suggests that the statins may not modulate IRBP induced uveoretinitis.

N-acetyl-L-cysteine ameliorates the inflammatory disease process in experimental autoimmune encephalomyelitis in Lewis rats

We report that N-acetyl-L-cysteine (NAC) treatment blocked induction of TNF-alpha, IL-1beta, IFN-gamma and iNOS in the CNS and attenuated clinical disease in the myelin basic protein induced model of experimental allergic encephalomyelitis (EAE) in Lewis rats. Infiltration of mononuclear cells into the CNS and induction of inflammatory cytokines and iNOS in multiple sclerosis (MS) and EAE have been implicated in subsequent disease progression and pathogenesis. To understand the mechanism of efficacy of NAC against EAE, we examined its effect on the production of cytokines and the infiltration of inflammatory cells into the CNS. NAC treatment attenuated the transmigration of mononuclear cells thereby lessening the neuroinflammatory disease. Splenocytes from NAC-treated EAE animals showed reduced IFN-gamma production, a Th1 cytokine and increased IL-10 production, an anti-inflammatory cytokine. Further, splenocytes from NAC-treated EAE animals also showed decreased nitrite production when stimulated in vitro by LPS. These observations indicate that NAC treatment may be of therapeutic value in MS against the inflammatory disease process associated with the infiltration of activated mononuclear cells into the CNS.

Therapy with statins in patients with refractory rheumatic diseases: a preliminary study

We have explored the therapeutic potential of statins in patients with different inflammatory rheumatic diseases refractory to conventional therapy. We found that simvastatin (80mg o.d. for eight days) induced a rapid and significant reduction in proteinuria levels in three systemic lupus erythematosus (SLE) patients. A similar kind of therapy had a marked beneficial effect in a patient with Wegener's granulomatosis and a patient with erythema nodosum. On the other hand, five patients with rheumatoid arthritis (RA) who received atorvastatin for eight days (20mg/day) showed reduction in C-reactive protein levels and a clinical improvement that was classified as an ACR20 response. Prior to the administration of statins, all these patients had received aggressive conventional therapy with no satisfactory response. A significant reduction in spontaneous apoptosis of peripheral blood lymphocytes and expression of CD69 and HLA-DR was observed in SLE patients after simvastatin therapy. These results prompted us to perform a pilot short-time comparative (simvastatin versus chloroquine) open clinical trial in 15 patients with RA who were receiving methotrexate as a single disease modifying antirheumatic drug with no satisfactory response. Most patients (9/10) who received simvastatin (40mg/day) showed an ACR50 or better response after eight weeks, whereas such a response was not observed in any patient (0/5) treated with chloroquine. Our preliminary results indicate that statins may be an important therapeutic tool for the treatment of inflammatory rheumatic diseases.

Modulation of macrophage function and metabolism

Several drugs or pharmacologically active molecules such as statins, calcium antagonists, and PPAR agonists have been shown to affect macrophage functions that contribute to atherosclerosis and modulate plaque stability. For example, the modulation of matrix metalloproteinase secretion and cholesterol metabolism in macrophages may help to prevent cardiovascular disease independently of the correction of risk factors.

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.

Simvastatin reduces MMP-3 level in interleukin 1beta stimulated human chondrocyte culture

OBJECTIVES

Matrix metalloproteinases (MMPs) produced by chondrocytes play a role in the development of cartilage degradation in joint diseases. Moreover, inhibition of MMP secretion by macrophages accumulating in arteriosclerotic plaques would account for the plaque stabilising activity of statins in cardiovascular patients. Recently, simvastatin has been shown to inhibit both developing and established collagen induced arthritis in a murine model. We thus decided to investigate the effect of simvastatin on the production of MMP-3 from cultured interleukin (IL)1 stimulated human chondrocytes.

METHODS

Cells from human cartilage, obtained from eight subjects with osteoarthritis undergoing surgery for total hip prostheses, were cultured in the presence of different concentrations of simvastatin (5, 10, and 50 micromol/l) with and without IL1beta (5 ng/ml). MMP-3 level was measured in the culture medium after 48 h of incubation.

RESULTS

IL1beta stimulation of chondrocytes increased MMP-3 concentration in the cultures (from 0.69 (0.09) to 1.94 (0.12) ng/microg protein). Incubation with simvastatin was associated with a dose dependent reduction in MMP-3 increase, both in the presence (-15%, -17%, and -26% with 5, 10, and 50 micromol/l, respectively) and in the absence (-32% with 50 micromol/l) of IL1beta. The inhibiting effect of simvastatin was completely reversed by the addition of mevalonate (100 micromol/l) or farnesol (10 micromol/l).

CONCLUSIONS

Our data show that simvastatin, by blocking HMGCoA-reductase and interfering in the prenylation processes, is able to inhibit MMP-3 production from cultured human chondrocytes that have been either unstimulated or stimulated with IL1beta, thus suggesting a possible additional mechanism for statins in counteracting chronic joint disease related cartilage damage.

Effect of the statin atorvastatin on intracellular signalling by the prostacyclin receptor in vitro and in vivo

Prostacyclin plays a central role within the vasculature. We have previously established that the prostacyclin receptor (IP) undergoes isoprenylation, a lipid modification obligate for its function. The aim of the current study was to investigate the effect of the hydroxy methyl glutaryl co-enzyme A reductase inhibitor atorvastatin on signalling and function of the IP expressed in mammalian whole cells and in platelets isolated from patients undergoing therapeutic intervention with atorvastatin. Initially, the effect of atorvastatin on signalling by the human (h) and mouse (m) IP overexpressed in human embryonic kidney 293 cells and the hIP endogenously expressed in human erythroleukaemic 92.1.7 cells was investigated. Atorvastatin significantly reduced IP-mediated cAMP generation (IC(50) 6.6-11.1 microm) and [Ca(2+)](i) mobilization (IC(50) 7.2-16.4 microm) in a concentration-dependent manner, but had no effect on signalling by the nonisoprenylated beta(2) adrenergic receptor or the alpha or beta isoforms of the human thromboxane A(2) receptor (TP). Moreover, atorvastatin significantly reduced IP-mediated crossdesensitization of signalling by TP alpha (IC(50) 10.4 microm), but not by TP beta. In contrast to the whole-cell data, atorvastatin therapy did not interfere with IP-mediated cAMP generation or IP-induced inhibition of TP-mediated aggregation of platelets isolated from human volunteers undergoing therapeutic intervention with atorvastatin (10-80 mg per daily dose). In conclusion, while data generated in whole cells indicated that atorvastatin significantly impairs signalling by both the hIP and mP, the in vivo clinical data indicated that, at the administered therapeutic dose, atorvastatin does not significantly compromise IP signalling and function in humans.

Prior statin therapy is associated with a decreased rate of severe sepsis

BACKGROUND

Statins have anti-inflammatory properties that are independent of their lipid-lowering abilities. We hypothesized that statin therapy before the onset of an acute bacterial infection may have a protective effect against severe sepsis. The aim of this study was to determine whether patients treated with statins develop severe sepsis less frequently.

METHODS AND RESULTS

In this prospective observational cohort study, consecutive patients admitted with presumed or documented acute bacterial infection were enrolled. The primary outcomes were the rate of severe sepsis and intensive care unit (ICU) admission. Of the 361 patients enrolled, 82 (22.7%) were treated with statins before their admission. Both groups had a similar severity of illness on admission. Severe sepsis developed in 19% of patients in the no-statin group and in only 2.4% of the statin group (P<0.001). Statin treatment was associated with a relative risk of developing severe sepsis of 0.13 (95% CI, 0.03 to 0.52) and an absolute risk reduction of 16.6%. The overall ICU admission rate was 10.2% (37/361): 12.2% of the no-statin group required ICU admission, whereas in the statin group only 3.7% were admitted to the ICU (P=0.025), reflecting a relative risk of ICU admission of 0.30 (95% CI, 0.1 to 0.95).

CONCLUSIONS

Prior therapy with statins may be associated with a reduced rate of severe sepsis and ICU admission. If supported by prospective controlled trials, statins may have a role in the primary prevention of sepsis.

Role of statin therapy in the coronary bypass patient

Statins have been proven to prevent or delay ischemic events in patients at risk for atherosclerotic coronary disease. Increasing evidence suggests that statin therapy is also beneficial to patients undergoing coronary revascularization. In this review statin therapy will be shown to improve vein graft patency, minimize recurrent ischemic events, and decrease the need for repeat revascularization procedures in patients who have undergone coronary artery bypass grafting.

HMG-CoA reductase inhibitors are associated with decreased serum neopterin levels in stable coronary artery disease

Neopterin, a marker of stimulated cellular immune response, is increased in unstable angina, acute myocardial infarction and possibly stable coronary artery disease. 3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) have anti-inflammatory properties, but their effect on neopterin is largely unknown. Neopterin was measured in 232 patients undergoing elective coronary angiography and compared to the degree of atherosclerosis, use of concomitant medications and demographics. Neopterin was lower in subjects using statins (n = 66) compared to those not taking statins (median (range): 6.65 (4.1-18.3) vs. 7.70 (3.6-29.1) nmol/l, p < 0.0001). This association was also found in the subgroup of patients with coronary artery disease (1-3-vessel disease, n = 164; 6.60 (4.1-18.3) vs. 7.80 (3.6-29.1) nmol/l, p = 0.0012), whereas only a slight tendency toward lower neopterin levels was found in the group without atherosclerosis (6.90 (5.1-16.0) vs. 7.60 (4.0-18.5) nmol/l, p = 0.17). In patients with coronary atherosclerosis, neopterin concentrations were lower in smokers (n = 105) compared to non-smokers (7.20 (3.6-29.1) vs. 7.90 (4.4-18.6) nmol/l, p < 0.02), confirming previous observations. However, use of statins was associated with lower neopterin levels in both non-smokers and smokers (6.70 (4.1-18.3) vs. 7.60 (3.6-29.1) nmol/l, p < 0.05, and 6.20 (5.2-16.0) vs. 7.80 (4.4-18.6) nmol/l, p < 0.05, respectively). Overall, similar serum neopterin concentrations were found in patients with coronary atherosclerosis and those without. In accordance with their anti-inflammatory effects, the use of statins is associated with lower neopterin levels in patients undergoing elective coronary angiography.

Inhibition of Rho family GTPases results in increased TNF-alpha production after lipopolysaccharide exposure

These studies demonstrate that treatment of macrophages with lovastatin, a cholesterol-lowering drug that blocks farnesylation and geranylgeranylation of target proteins, increases LPS-induced TNF-alpha production. This is reversed by the addition of mevalonate, which bypasses the lovastatin block. Examination of membrane localization of RhoA, Cdc42, Rac1, and Ras demonstrated decreased membrane localization of the geranylgeranylated Rho family members (RhoA, Cdc42, and Rac1) with no change in the membrane localization of farnesylated Ras. LPS-induced TNF-alpha production in the presence of the Rho family-specific blocker (toxin B from Clostridium difficile) was significantly enhanced consistent with the lovastatin data. One intracellular signaling pathway that is required for TNF-alpha production by LPS is the extracellular signal-regulated kinase (ERK). Significantly, we found prolonged ERK activation after LPS stimulation of lovastatin-treated macrophages. When we inhibited ERK, we blocked the lovastatin-induced increase in TNF-alpha production. As a composite, these studies demonstrate a negative role for one or more Rho family GTPases in LPS-induced TNF-alpha production.

Statins may potentiate bisphosphonates anticancer properties: a new pharmacological approach?

Both statins and bisphosphonates may inhibit cancer proliferation by two main different mechanisms: inducing apoptosis along cholesterol synthesis pathway and by antiangiogenic properties. Moreover, also an immunomediated mechanism could be involved in anticancer properties of these molecules. The association of these two drugs could represent an interesting pharmacological approach in anticancer treatment. The available data offer the rationale for future in vitro studies aimed at evaluating proapoptotic and antiangiogenic action of this association. If the results of vitro studies should confirm the hypothesis that statins potentiate the action of bisphosphonates, further clinical investigations could be mandatory to evaluate the efficacy of this new pharmacological approach in anticancer therapy.

The pleiotropic effects of HMG-CoA reductase inhibitors: their role in osteoporosis and dementia

HMG-CoA reductase is the rate-limiting enzyme for cholesterol synthesis and its inhibition exerts profound effects on cellular metabolism. Inhibitors of this enzyme are used in clinical practice to lower plasma cholesterol levels and are commonly collectively referred to as 'statins'. A number of in vitro, in vivo animal, and clinical studies suggest that properties of statins other than cholesterol lowering may be of biological importance. These diverse properties are often referred to as 'pleiotropic' and suggest that statins may affect a number of diseases of ageing. In this article we review the biological plausibility and clinical evidence of a role for statins in modulating two diseases of ageing: osteoporosis and dementia (including Alzheimer's disease). In both diseases, there is a sound cellular and laboratory basis for a plausible therapeutic effect of statins. In the case of osteoporosis, there are conflicting data regarding clinical benefit, with both negative and positive results reported. In particular, secondary analyses of randomised, controlled studies have shown no reduction of fracture risk by statins. In the case of dementia there are fewer clinical studies but there is clear anticipated benefit in macrovascular dementias attributable to statin-mediated reduction of the risk of stroke. Overall, there are a lack of prospective, placebo-controlled, randomised data testing statins and modulation of the risk of osteoporosis-related fracture or of clinical dementia, where these are primary outcomes. Until such data are available, the use of statins appears promising but cannot be recommended as a primary therapeutic modality for either condition.

Cardiovascular risk factors, monitoring, and therapy for HIV-infected patients

Cardiovascular complications are important contributors to morbidity and mortality in HIV-infected patients. These complications can usually be detected at subclinical levels with monitoring, which can help guide targeted interventions. This article reviews available data on types and frequency of cardiovascular manifestations in HIV-infected patients and proposes monitoring strategies aimed at early subclinical detection. In particular, we recommend routine echocardiography for HIV-infected patients, even those with no evidence of cardiovascular disease. We also review preventive and therapeutic cardiovascular interventions. For procedures that have not been studied in HIV-infected patients, we extrapolate from evidence-based guidelines for the general population.