Pharmacology of 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins), including rosuvastatin and pitavastatin

The Role of Small Molecules Containing Fluorine Atoms in Medicine and Imaging Applications

The fluorine atom possesses many intrinsic properties that can be beneficial when incorporated into small molecules. These properties include the atom's size, electronegativity, and ability to block metabolic oxidation sites. Substituents that feature fluorine and fluorine-containing groups are currently prevalent in drugs that lower cholesterol, relieve asthma, and treat anxiety disorders, as well as improve the chemical properties of various medications and imaging agents. The dye scaffolds (fluorescein/rhodamine, coumarin, BODIPY, carbocyanine, and squaraine dyes) reported will address the incorporation of the fluorine atom in the scaffold and the contribution it provides to its application as an imaging agent. It is also important to recognize radiolabeled fluorine atoms used for PET imaging in the early detection of diseases. This review will discuss the many benefits of incorporating fluorine atoms into small molecules and give examples of fluorinated molecules used in the pharmaceutical industry and imaging techniques.

Synergistic effects of Momordica charantia, Nigella sativa, and Anethum graveolens on metabolic syndrome targets: In vitro enzyme inhibition and in silico analyses

Momordica charantia, Nigella sativa, and Anethum graveolens are established medicinal plants possessing noted anti-diabetic and anti-obesity properties. However, the molecular mechanisms underscoring their inhibitory effects on pancreatic lipase, α-glucosidase, and HMG-CoA reductase remain unexplored. This study aimed to elucidate the efficacy of various NS, MC, and AG blends in modulating the enzymatic activity of pancreatic lipase, HMG-CoA reductase, and a-glucosidase, utilizing an integrative approach combining in vitro assessments and molecular modeling techniques. A factorial design matrix generated eight distinct concentration combinations of NS, MC, and AG, subsequently subjected to in vitro enzyme inhibition assays. Molecular docking analyses using AutoDock Vina, molecular dynamics simulations, MMPBSA calculations, and principal component analysis, were executed with Gromacs to discern the interaction dynamics between the compounds and target enzymes. A formulation comprising NS:MC:AG at a 215:50:35 μg/mL ratio yielded significant inhibition of pancreatic lipase (IC50: 74.26 ± 4.27 μg/mL). Moreover, a concentration combination of 215:80:35 μg/mL effectively inhibited both α-glucosidase (IC50: 66.09 ± 3.98 μg/mL) and HMGCR (IC50: 129.03 μg/mL). Notably, MC-derived compounds exhibited superior binding affinity towards all three enzymes, compared to their reference molecules, with diosgenin, Momordicoside I, and diosgenin displaying binding affinities of -11.0, -8.8, and -7.9 kcal/mol with active site residues of pancreatic lipase, α-glucosidase, and HMGCR, respectively. Further, 100 ns molecular dynamics simulations revealed the formation and stabilization of non-bonded interactions between the compounds and the enzymes' active site residues. Through a synergistic application of in vitro and molecular modeling methodologies, this study substantiated the potent inhibitory activity of the NS:MC:AG blend (at a ratio of 215:80:35 μg/mL) and specific MC compounds against pancreatic lipase, α-glucosidase, and HMGCR. These findings provide invaluable insights into the molecular underpinnings of these medicinal plants' anti-diabetic and anti-obesity effects and may guide future therapeutic development.

Improvement of synaptic plasticity and cognitive function in RASopathies-a monocentre, randomized, double-blind, parallel-group, placebo-controlled, cross-over clinical trial (SynCoRAS)

BACKGROUND

Cognitive impairment is a common medical issue in rat sarcoma (RAS) pathway disorders, so-called RASopathies, like Neurofibromatosis type 1 (NF1) or Noonan syndrome (NS). It is presumed to be caused by impaired synaptic plasticity. In animal studies, pathway-specific pharmacological interventions with lovastatin (LOV) and lamotrigine (LTG) have been shown to improve synaptic plasticity as well as cognitive function. The aim of this clinical trial is to translate the findings of animal studies to humans and to probe the effect of lovastatin (NS) and lamotrigine (NS and NF1) on synaptic plasticity and cognitive function/alertness in RASopathies.

METHODS

Within this phase IIa, monocentre, randomized, double-blind, parallel-group, placebo-controlled, cross-over clinical trial (syn. SynCoRAS), three approaches (approaches I-III) will be carried out. In patients with NS, the effect of LTG (approach I) and of LOV (approach II) is investigated on synaptic plasticity and alertness. LTG is tested in patients with NF1 (approach III). Trial participants receive a single dose of 300 mg LTG or placebo (I and III) and 200 mg LOV or placebo (II) daily for 4 days with a cross-over after at least 7 days. Synaptic plasticity is investigated using a repetitive high-frequency transcranial magnetic stimulation (TMS) protocol called quadri-pulse theta burst stimulation (qTBS). Attention is examined by using the test of attentional performance (TAP). Twenty-eight patients are randomized in groups NS and NF1 with n = 24 intended to reach the primary endpoint (change in synaptic plasticity). Secondary endpoints are attention (TAP) and differences in short interval cortical inhibition (SICI) between placebo and trial medication (LTG and LOV).

DISCUSSION

The study is targeting impairments in synaptic plasticity and cognitive impairment, one of the main health problems of patients with RASopathies. Recent first results with LOV in patients with NF1 have shown an improvement in synaptic plasticity and cognition. Within this clinical trial, it is investigated if these findings can be transferred to patients with NS. LTG is most likely a more effective and promising substance improving synaptic plasticity and, consecutively, cognitive function. It is expected that both substances are improving synaptic plasticity as well as alertness. Changes in alertness may be a precondition for improvement of cognition.

TRIAL REGISTRATION

The clinical trial is registered in ClinicalTrials.gov (NCT03504501; https://www.

CLINICALTRIALS

gov ; date of registration: 04/11/2018) and in EudraCT (number 2016-005022-10).

A novel machine learning-based screening identifies statins as inhibitors of the calcium pump SERCA

We report a novel small-molecule screening approach that combines data augmentation and machine learning to identify Food and Drug Administration (FDA)-approved drugs interacting with the calcium pump (Sarcoplasmic reticulum Ca2+-ATPase, SERCA) from skeletal (SERCA1a) and cardiac (SERCA2a) muscle. This approach uses information about small-molecule effectors to map and probe the chemical space of pharmacological targets, thus allowing to screen with high precision large databases of small molecules, including approved and investigational drugs. We chose SERCA because it plays a major role in the excitation-contraction-relaxation cycle in muscle and it represents a major target in both skeletal and cardiac muscle. The machine learning model predicted that SERCA1a and SERCA2a are pharmacological targets for seven statins, a group of FDA-approved 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors used in the clinic as lipid-lowering medications. We validated the machine learning predictions by using in vitro ATPase assays to show that several FDA-approved statins are partial inhibitors of SERCA1a and SERCA2a. Complementary atomistic simulations predict that these drugs bind to two different allosteric sites of the pump. Our findings suggest that SERCA-mediated Ca2+ transport may be targeted by some statins (e.g., atorvastatin), thus providing a molecular pathway to explain statin-associated toxicity reported in the literature. These studies show the applicability of data augmentation and machine learning-based screening as a general platform for the identification of off-target interactions and the applicability of this approach extends to drug discovery.

Investigating potential anti-proliferative activity of different statins against five cancer cell lines

Statins have been reported to have potential anti-proliferative effects through an unknown mechanism. This study aims to investigate the anti-proliferative activities of five statins, including simvastatin, rosuvastatin, fluvastatin, atorvastatin, and pravastatin, against five different cancer cell lines; cervical epithelial carcinoma DoTc2 4510, malignant melanoma A-375, muscle Ewing's sarcoma A-673, hepatocellular carcinoma HUH-7, as well as breast cancer cells MCF-7. At 100 µM, simvastatin and atorvastatin significantly inhibited 70% of cellular proliferation. At the same concentration, rosuvastatin and fluvastatin showed about 50% of inhibition only in A-375 and A-673 cancer cells in a time- and dose-dependent manner. Of all the statin drugs used, pravastatin had the least inhibitory effect on all the cancer cell lines. Western Blot analysis showed a decrease in mTOR level, and the expression of p53 tumour suppression and BCL-2 proteins was relatively elevated compared to the untreated cells. Simvastatin and atorvastatin may inhibit cellular proliferation via BCL-2/p53, Bax/Bak, and PI3K/Akt/mTOR signalling pathways. This is the first research to evaluate the anti-cancer effects of simvastatin, rosuvastatin, fluvastatin, atorvastatin, and pravastatin against five different cell lines from distinct origins and provided a relevant comparison of their efficacies for their anti-proliferative activity.

Targeting lipid biosynthesis pathways for hepatitis B virus cure

Chronic hepatitis B virus (HBV) infection is characterized by the presence of high circulating levels of non-infectious lipoprotein-like HBV surface antigen (HBsAg) particles thought to contribute to chronic immune dysfunction in patients. Lipid and metabolomic analysis of humanized livers from immunodeficient chimeric mice (uPA/SCID) revealed that HBV infection dysregulates several lipid metabolic pathways. Small molecule inhibitors of lipid biosynthetic pathway enzymes acetyl-CoA carboxylase (ACC), fatty acid synthase, and subtilisin kexin isozyme-1/site-1 protease in HBV-infected HepG2-NTCP cells demonstrated potent and selective reduction of extracellular HBsAg. However, a liver-targeted ACC inhibitor did not show antiviral activity in HBV-infected liver chimeric mice, despite evidence of on-target engagement. Our study suggests that while HBsAg production may be dependent on hepatic de novo lipogenesis in vitro, this may be overcome by extrahepatic sources (such as lipolysis or diet) in vivo. Thus, a combination of agents targeting more than one lipid metabolic pathway may be necessary to reduce HBsAg levels in patients with chronic HBV infection.

Biological Actions, Implications, and Cautions of Statins Therapy in COVID-19

The Coronavirus Disease 2019 (COVID-19) showed worse prognosis and higher mortality in individuals with obesity. Dyslipidemia is a major link between obesity and COVID-19 severity. Statins as the most common lipid regulating drugs have shown favorable effects in various pathophysiological states. Importantly, accumulating observational studies have suggested that statin use is associated with reduced risk of progressing to severe illness and in-hospital death in COVID-19 patients. Possible explanations underlie these protective impacts include their abilities of reducing cholesterol, suppressing viral entry and replication, anti-inflammation and immunomodulatory effects, as well as anti-thrombosis and anti-oxidative properties. Despite these benefits, statin therapies have side effects that should be considered, such as elevated creatinine kinase, liver enzyme and serum glucose levels, which are already elevated in severe COVID-19. Concerns are also raised whether statins interfere with the efficacy of COVID-19 vaccines. Randomized controlled trials are being conducted worldwide to confirm the values of statin use for COVID-19 treatment. Generally, the results suggest no necessity to discontinue statin use, and no evidence suggesting interference between statins and COVID-19 vaccines. However, concomitant administration of statins and COVID-19 antiviral drug Paxlovid may increase statin exposure and the risk of adverse effects, because most statins are metabolized mainly through CYP3A4 which is potently inhibited by ritonavir, a major component of Paxlovid. Therefore, more clinical/preclinical studies are still warranted to understand the benefits, harms and mechanisms of statin use in the context of COVID-19.

Statins and Bempedoic Acid: Different Actions of Cholesterol Inhibitors on Macrophage Activation

Statins represent the most prescribed class of drugs for the treatment of hypercholesterolemia. Effects that go beyond lipid-lowering actions have been suggested to contribute to their beneficial pharmacological properties. Whether and how statins act on macrophages has been a matter of debate. In the present study, we aimed at characterizing the impact of statins on macrophage polarization and comparing these to the effects of bempedoic acid, a recently registered drug for the treatment of hypercholesterolemia, which has been suggested to have a similar beneficial profile but fewer side effects. Treatment of primary murine macrophages with two different statins, i.e., simvastatin and cerivastatin, impaired phagocytotic activity and, concurrently, enhanced pro-inflammatory responses upon short-term lipopolysaccharide challenge, as characterized by an induction of tumor necrosis factor (TNF), interleukin (IL) 1β, and IL6. In contrast, no differences were observed under long-term inflammatory (M1) or anti-inflammatory (M2) conditions, and neither inducible NO synthase (iNOS) expression nor nitric oxide production was altered. Statin treatment led to extracellular-signal regulated kinase (ERK) activation, and the pro-inflammatory statin effects were abolished by ERK inhibition. Bempedoic acid only had a negligible impact on macrophage responses when compared with statins. Taken together, our data point toward an immunomodulatory effect of statins on macrophage polarization, which is absent upon bempedoic acid treatment.

Comparative Study of Lipophilic Statin Activity in 2D and 3D in vitro Models of Human Breast Cancer Cell Lines MDA-MB-231 and MCF-7

Introduction

Statins are a type of drugs that are used to lower cholesterol level in blood. Since the early 1990s, it has been known that statins could be beneficial in cancer therapy. However, data remain controversial, especially regarding estrogen receptors status. Despite many studies in breast cancer models in vitro, the correlations of effects of separate statins in various model systems remain unclear.

Aim

Our aim was to evaluate the anticancer activity of lovastatin, mevastatin, pitavastatin and simvastatin on different subtypes of human breast cancer (MDA-MB-231 and MCF-7 cell lines) in spatially different 2D and 3D cultures in vitro.

Materials and Methods

Cell viability was tested using MTT assay. Effect of statins on cell colony formation was evaluated by calculating breast cancer cell colony area and number. The effect on cell migration was estimated by “wound healing” assay. The activity of compounds in 3D cultures was evaluated by measuring the spheroid size changes during incubation.

Results

Among the tested statins, pitavastatin had the greatest effect on the viability of breast cancer MDA-MB-231 and MCF-7 cell lines. The mevastatin and pitavastatin mostly decreased the MDA-MB-231 and MCF-7 cell colony formation. All statins at 90% of their estimated effective concentration (EC₅₀) and simvastatin at 10% of its EC₅₀ concentration suppressed the MCF-7 cells migration in “wound healing” assay. Only higher concentrations of mevastatin and pitavastatin slowed down the MDA-MB-231 cell migration. Statins showed different activity on 3D cell cultures growth. Lovastatin and simvastatin delayed the growth of MDA-MB-231 cell spheroids, while mevastatin and pitavastatin reduced the growth of MCF-7 spheroids.

Conclusion

Statins possess different anticancer activity in human breast cancer MDA-MB-231 and MCF-7 cell cultures. Pitavastatin and simvastatin showed the highest activity in most tested assays, especially against MCF-7 cell line.

A Microdose Cocktail to Evaluate Drug Interactions in Patients with Renal Impairment

Renal impairment (RI) is known to influence the pharmacokinetics of nonrenally eliminated drugs, although the mechanism and clinical impact is poorly understood. We assessed the impact of RI and single dose oral rifampin (RIF) on the pharmacokinetics of CYP3A, OATP1B, P-gp, and BCRP substrates using a microdose cocktail and OATP1B endogenous biomarkers. RI alone had no impact on midazolam (MDZ), maximum plasma concentration (C_max ), and area under the curve (AUC), but a progressive increase in AUC with RI severity for dabigatran (DABI), and up to ~2-fold higher AUC for pitavastatin (PTV), rosuvastatin (RSV), and atorvastatin (ATV) for all degrees of RI was observed. RIF did not impact MDZ, had a progressively smaller DABI drug-drug interaction (DDI) with increasing RI severity, a similar 3.1-fold to 4.4-fold increase in PTV and RSV AUC in healthy volunteers and patients with RI, and a diminishing DDI with RI severity from 6.1-fold to 4.7-fold for ATV. Endogenous biomarkers of OATP1B (bilirubin, coproporphyrin I/III, and sulfated bile salts) were generally not impacted by RI, and RIF effects on these biomarkers in RI were comparable or larger than those in healthy volunteers. The lack of a trend with RI severity of PTV and several OATP1B biomarkers, suggests that mechanisms beyond RI directly impacting OATP1B activity could also be considered. The DABI, RSV, and ATV data suggest an impact of RI on intestinal P-gp, and potentially BCRP activity. Therefore, DDI data from healthy volunteers may represent a worst-case scenario for clinically derisking P-gp and BCRP substrates in the setting of RI.

Cholesterol intake and statin use regulate neuronal G protein-gated inwardly rectifying potassium channels

Cholesterol, a critical component of the cellular plasma membrane, is essential for normal neuronal function. Cholesterol content is highest in the brain, where most cholesterol is synthesized de novo; HMG-CoA reductase controls the synthesis rate. Despite strict control, elevated blood cholesterol levels are common and are associated with various neurological disorders. G protein-gated inwardly rectifying potassium (GIRK) channels mediate the actions of inhibitory brain neurotransmitters. Loss of GIRK function enhances neuron excitability; gain of function reduces neuronal activity. However, the effect of dietary cholesterol or HMG-CoA reductase inhibition (i.e., statin therapy) on GIRK function remains unknown. Using a rat model, we compared the effects of a high-cholesterol versus normal diet both with and without atorvastatin, a widely prescribed HMG-CoA reductase inhibitor, on neuronal GIRK currents. The high-cholesterol diet increased hippocampal CA1 region cholesterol levels and correspondingly increased neuronal GIRK currents. Both phenomena were reversed by cholesterol depletion in vitro. Atorvastatin countered the high-cholesterol diet effects on neuronal cholesterol content and GIRK currents; these effects were reversed by cholesterol enrichment in vitro. Our findings suggest that high-cholesterol diet and atorvastatin therapy affect ion channel function in the brain by modulating neuronal cholesterol levels.

Drug delivery to the brain: how can nanoencapsulated statins be used in the clinic?

Statins are used for the primary and secondary prevention of cardiovascular disease by inhibiting cholesterol synthesis in the liver. Statins have also noncholesterol-related effects, called pleiotropic effects, which arise from statins' anti-inflammatory, immunomodulatory and antioxidant properties. These effects are especially attractive for the treatment of various brain diseases ranging from stroke to neurodegenerative diseases. Still, low brain concentrations after oral drug administration hinder the clinical application of statins in these pathologies. Pharmaceutical nanotechnologies may offer a solution to this problem, as local or targeted delivery of nanoencapsulated statins may increase brain availability. This special report rapidly summarizes the potential of statins in the treatment of brain diseases and the pharmaceutical nanotechnologies that could provide a viable approach to enable these indications.

Lipophilic Statins and the Risk of Intracranial Hemorrhage Following Ischemic Stroke: A Population-Based Study

BACKGROUND

Statins are commonly prescribed for the secondary prevention of ischemic stroke, but there is conflicting evidence as to whether they increase the risk of intracranial hemorrhage. Lipophilic statins cross the blood-brain barrier more freely than hydrophilic statins and may therefore increase the risk of intracranial hemorrhage.

OBJECTIVE

To determine whether, in older patients following ischemic stroke, receipt of lipophilic statins was associated with differences in the risk of intracranial hemorrhage.

METHODS

We conducted a population-based nested case-control study linking multiple healthcare databases between 1 April, 2001 and 31 March, 2015 in Ontario, Canada. Cases were Ontarians aged 66 years or older receiving a statin within 100 days preceding the development of intracranial hemorrhage within 1 year following ischemic stroke. Each case was matched with up to four controls who experienced ischemic stroke not complicated by intracranial hemorrhage but who also received a statin. We classified statins as lipophilic (atorvastatin, simvastatin, lovastatin, fluvastatin, and cerivastatin) or hydrophilic (pravastatin and rosuvastatin) based on their octanol/water partition coefficients. We calculated the odds ratio for the association between intracranial hemorrhage and receipt of lipophilic statins, with hydrophilic statins as the reference group.

RESULTS

We identified 2766 individuals who experienced intracranial hemorrhage during statin therapy after ischemic stroke and 11,060 matched controls. Relative to hydrophilic statins, lipophilic statins were not associated with an increased risk of intracranial hemorrhage (adjusted odds ratio 1.07; 95% confidence interval 0.97-1.19).

CONCLUSION

Among patients treated with a statin following ischemic stroke, the risk of intracranial hemorrhage is not influenced by statin lipophilicity.

Oxidative stress as a possible mechanism of statin-induced myopathy

Statins, inhibitors of hydroxy methyl glutaryl coenzyme-A (HMG-CoA) reductase, are the most widely used drugs for treating hypercholesterolemia. However, statins can cause disabling myopathy as their main adverse effect. Several molecular mechanisms underlie the statin-induced myopathy including the decrease in the levels of essential mevalonate and cholesterol derivatives. This review discusses a further mechanism involving the loss of other anti-oxidant defenses besides ubiquinone (Co-Q) in skeletal muscles which produce a significant amount of reactive oxygen species (ROS). Therefore, to maintain their function, skeletal muscles need a high level of anti-oxidants.

Comparative effect of statins on the risk of incident Alzheimer disease

Objective

To investigate whether fungus-derived statins are associated with a lower risk of incident Alzheimer disease (AD) compared with synthetic statins using real-world clinical practice data.

Methods

We identified a population-based retrospective cohort of patients aged ≥60 years newly prescribed a statin between January 1, 1994, and December 31, 2012, and followed until March 31, 2015, using the UK Clinical Practice Research Datalink. Statins were consecutively classified according to their type, lipophilicity, and potency. For each group, we calculated the crude AD incidence rates per 1,000 person-years. Time-dependent Cox proportional hazards models adjusted for propensity score deciles were used to estimate hazard ratios (HRs) with 95% confidence interval (CIs) of incident AD associated with different statin categories.

Results

Over the 18-year study period, we identified 465,085 statin users, including 7,669 patients who developed AD during 2,891,268 person-years of follow-up (incidence rate 2.65 [95% CI 2.59–2.71] per 1,000 person-years). Compared to synthetic, fungus-derived statins were associated with an increased risk of AD (HR 1.09, 95% CI 1.03–1.15). Lipophilic statins also were associated with higher AD risk (HR 1.18, 95% CI 1.09–1.27) compared to hydrophilic statins, while statin potency did not modify the risk of AD (adjusted HR 1.03, 95% CI 0.98–1.08). The risk was further reduced in sensitivity analyses.

Conclusion

Fungus-derived and lipophilic statins were not associated with decreased incidence of AD compared to synthetic and hydrophilic statins. The modest variations in the risk of incident AD observed between statin characteristics needs to be evaluated in future studies on their possible heterogeneous neuroprotective effect.

Differences of statin activity in 2D and 3D pancreatic cancer cell cultures

Purpose

To evaluate the anticancer activity of lovastatin (LOVA), mevastatin (MEVA), pitavastatin (PITA), and simvastatin (SIMVA) in 2D and 3D models of three human pancreatic cancer cell lines (BxPC-3, MIA PaCa-2, and PANC-1).

Methods

The effect of statins on cell viability was estimated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test. The activity of statins in 3D pancreatic cancer cell cultures was examined by measuring the size change of spheroids. The type of cell death was identified by cell staining with Hoechst 33342 and propidium iodide. The activity of statins on the clonogenicity of cancer cells was tested by evaluating the effect on the colony-forming ability of cells.

Results

The rank order of the activity of tested statins on cell viability was as follows: PITA > SIMVA > LOVA > MEVA. Among the tested statins, PITA had the greatest effect on cell viability (half maximal effective concentration values after 72 h on BxPC-3, MIA PaCa-2, and PANC-1 cells were 1.4±0.4 μM, 1.0±0.2 μM, and 1.0±0.5 μM, respectively). PITA also showed the strongest effect on tumor spheroid growth. Statins suppressed the colony formation of cancer cells. PITA demonstrated the greatest reduction in colony size and number. Apoptosis and necrosis assay results showed that at lower concentrations statins mostly induced cell death through apoptosis, whereas higher concentrations of compounds activated also necrotic processes.

Conclusion

Statins, especially PITA, demonstrate an anticancer activity against pancreatic cancer cell lines BxPC-3, MIA PaCa-2, and PANC-1 in both 2D and 3D models.

Could simvastatin be considered as a potential therapy for chronic lung diseases? A debate on the pros and cons

INTRODUCTION

Simvastatin (SV) is a drug from the statin class, currently used orally as an anti-cholesterolemic drug. It inhibits the 3-hydroxy-3-methyl-glutaryl-Coenzyme A (HMG-CoA) reductase to reduce cholesterol synthesis. Recently, it has been found that SV also has several other protective pharmacological actions unrelated to its anti-cholesterol effects that might be beneficial in the treatment of chronic airway diseases.

AREAS COVERED

This review summarizes the evidence relating to SV as a potential anti-inflammatory, anti-oxidant and muco-inhibitory agent, administered both orally and via pulmonary inhalation, and discusses its pro and cons. Evidence could potentially be used to support the delivery of SV as inhaled formulation for the treatment of chronic respiratory diseases.

EXPERT OPINION

The use of SV as anti-inflammatory, anti-oxidant and muco-inhibitory agent for drug delivery to the lung is promising. Inhaled SV formulations could allow the delivery profile to be customized and optimized to take advantage of the rapid onset of action, low systemic side effect and improved physico-chemical stability. This treatment could potentially to be used clinically for the localized treatment of lung diseases where inflammation and oxidative stress production is present.

Development and Validation of an HPLC Method for Simultaneous Quantification of Clopidogrel Bisulfate, Its Carboxylic Acid Metabolite, and Atorvastatin in Human Plasma: Application to a Pharmacokinetic Study

A simple, sensitive, and specific reversed phase liquid chromatographic method was developed and validated for simultaneous quantification of clopidogrel, its carboxylic acid metabolite, and atorvastatin in human serum. Plasma samples were deproteinized with acetonitrile and ibuprofen was chosen as internal standard. Chromatographic separation was performed on an BDS Hypersil C18 column (250 × 4.6 mm; 5 μm) via gradient elution with mobile phase consisting of 10 mM phosphoric acid (sodium) buffer solution (pH = 2.6 adjusted with 85% orthophosphoric acid) : acetonitrile : methanol with flow rate of 1 mL·min(-1). Detection was achieved with PDA detector at 220 nm. The method was validated in terms of linearity, sensitivity, precision, accuracy, limit of quantification, and stability tests. Calibration curves of the analytes were found to be linear in the range of 0.008-2 μg·mL(-1) for clopidogrel, 0.01-4 μg·mL(-1) for its carboxylic acid metabolite, and 0.005-2.5 μg·mL(-1) for atorvastatin. The results of accuracy (as recovery) with ibuprofen as internal standard were in the range of 96-98% for clopidogrel, 94-98% for its carboxylic acid metabolite, and 90-99% for atorvastatin, respectively.

Pharmacological modulation of dietary lipid-induced cerebral capillary dysfunction: Considerations for reducing risk for Alzheimer's disease

An increasing body of evidence suggests that cerebrovascular dysfunction and microvessel disease precede the evolution of hallmark pathological features that characterise Alzheimer's disease (AD), consistent with a causal association for onset or progression. Recent studies, principally in genetically unmanipulated animal models, suggest that chronic ingestion of diets enriched in saturated fats and cholesterol may compromise blood-brain barrier (BBB) integrity resulting in inappropriate blood-to-brain extravasation of plasma proteins, including lipid macromolecules that may be enriched in amyloid-β (Aβ). Brain parenchymal retention of blood proteins and lipoprotein bound Aβ is associated with heightened neurovascular inflammation, altered redox homeostasis and nitric oxide (NO) metabolism. Therefore, it is a reasonable proposition that lipid-lowering agents may positively modulate BBB integrity and by extension attenuate risk or progression of AD. In addition to their robust lipid lowering properties, reported beneficial effects of lipid-lowering agents were attributed to their pleiotropic properties via modulation of inflammation, oxidative stress, NO and Aβ metabolism. The review is a contemporary consideration of a complex body of literature intended to synthesise focussed consideration of mechanisms central to regulation of BBB function and integrity. Emphasis is given to dietary fat driven significant epidemiological evidence consistent with heightened risk amongst populations consuming greater amounts of saturated fats and cholesterol. In addition, potential neurovascular benefits associated with the use of hypolipidemic statins, probucol and fenofibrate are also presented in the context of lipid-lowering and pleiotropic properties.

Statin treatment alters serum n-3 to n-6 polyunsaturated fatty acids ratio in patients with dyslipidemia

Background

The effects of statins on serum n-3 to n-6 polyunsaturated fatty acids (PUFAs) levels have not been fully evaluated. We examined the effects of two types of statins (rosuvastatin and pitavastatin) on serum PUFAs levels and their ratios in patients with dyslipidemia.

Findings

A total of 46 patients who were not receiving lipid-lowering therapy were randomly assigned to receive either 2.5 mg/day of rosuvastatin or 2 mg/day of pitavastatin. Serum PUFAs levels were measured at baseline, at 4 weeks, and at 12 weeks. Rosuvastatin was used to treat 23 patients, and the remaining 23 patients were treated using pitavastatin. Serum docosahexaenoic acid (DHA) levels decreased significantly at 12 weeks in both groups (rosuvastatin: from 169.6 to 136.3 μg/mL, p = 0.006; pitavastatin: from 188.6 to 153.9 μg/mL, p = 0.03). However, serum levels of eicosapentaenoic acid (EPA) and arachidonic acid (AA) did not change. In addition, the EPA/AA ratio did not change, whereas the DHA/AA ratio decreased significantly at 12 weeks in both groups (rosuvastatin: from 0.99 to 0.80, p = 0.01; pitavastatin: from 1.14 to 0.91, p = 0.003). No adverse events were observed during the study period.

Conclusions

In this small, open-label, pilot study, rosuvastatin and pitavastatin decreased serum DHA levels and the DHA/AA ratio in patients with dyslipidemia.

Optimized zein nanospheres for improved oral bioavailability of atorvastatin

BACKGROUND

This work focuses on the development of atorvastatin utilizing zein, a natural, safe, and biocompatible polymer, as a nanosized formulation in order to overcome the poor oral bioavailability (12%) of the drug.

METHODS

Twelve experimental runs of atorvastatin-zein nanosphere formula were formulated by a liquid-liquid phase separation method according to custom fractional factorial design to optimize the formulation variables. The factors studied were: weight % of zein to atorvastatin (X1), pH (X2), and stirring time (X3). Levels for each formulation variable were designed. The selected dependent variables were: mean particle size (Y1), zeta potential (Y2), drug loading efficiency (Y3), drug encapsulation efficiency (Y4), and yield (Y5). The optimized formulation was assayed for compatibility using an X-ray diffraction assay. In vitro diffusion of the optimized formulation was carried out. A pharmacokinetic study was also done to compare the plasma profile of the atorvastatin-zein nanosphere formulation versus atorvastatin oral suspension and the commercially available tablet.

RESULTS

The optimized atorvastatin-zein formulation had a mean particle size of 183 nm, a loading efficiency of 14.86%, and an encapsulation efficiency of 29.71%. The in vitro dissolution assay displayed an initial burst effect, with a cumulative amount of atorvastatin released of 41.76% and 82.3% after 12 and 48 hours, respectively. In Wistar albino rats, the bioavailability of atorvastatin from the optimized atorvastatin-zein formulation was 3-fold greater than that from the atorvastatin suspension and the commercially available tablet.

CONCLUSION

The atorvastatin-zein nanosphere formulation improved the oral delivery and pharmacokinetic profile of atorvastatin by enhancing its oral bioavailability.

Drug-drug interactions that interfere with statin metabolism

INTRODUCTION

Lipid-lowering drugs, especially hydroxymethylglutaryl-CoA reductase inhibitors (statins), are widely used in the treatment and prevention of atherosclerotic diseases. The benefits of statins are well documented. However, myotoxic side effects, which can sometimes be severe, including myopathy or rhabdomyolysis, have been associated with the use of statins. In some cases, this toxicity is associated with pharmacokinetic alterations. Potent inhibitors of CYP 3A4 significantly increase plasma concentrations of the active forms of simvastatin, lovastatin and atorvastatin. Fluvastatin is metabolized by CYP2C9, while pravastatin, rosuvastatin and pitavastatin are not susceptible to inhibition by any CYP.

AREAS COVERED

This review discusses the pharmacokinetic aspects of the drug-drug interaction with statins and genetic polymorphisms in CYPs, which are involved in the metabolism of statins, and highlights the importance of establishing a system utilizing electronic medical information practically to avoid adverse drug reactions.

EXPERT OPINION

An understanding of the mechanisms underlying statin interactions will help to minimize drug interactions and develop statins that are less prone to adverse interactions. Quantitatively analyzed information for the low-density lipoprotein cholesterol lowering effects of statin based on electronic medical records may be useful for avoiding the adverse effect of statins.

Lovastatin improves impaired synaptic plasticity and phasic alertness in patients with neurofibromatosis type 1

Background

Neurofibromatosis type 1 (NF1) is one of the most common genetic disorders causing learning disabilities by mutations in the neurofibromin gene, an important inhibitor of the RAS pathway. In a mouse model of NF1, a loss of function mutation of the neurofibromin gene resulted in increased gamma aminobutyric acid (GABA)-mediated inhibition which led to decreased synaptic plasticity and deficits in attentional performance. Most importantly, these defictis were normalized by lovastatin. This placebo-controlled, double blind, randomized study aimed to investigate synaptic plasticity and cognition in humans with NF1 and tried to answer the question whether potential deficits may be rescued by lovastatin.

Methods

In NF1 patients (n = 11; 19–44 years) and healthy controls (HC; n = 11; 19–31 years) paired pulse transcranial magnetic stimulation (TMS) was used to study intracortical inhibition (paired pulse) and synaptic plasticity (paired associative stimulation). On behavioural level the Test of Attentional Performance (TAP) was used. To study the effect of 200 mg lovastatin for 4 days on all these parameters, a placebo-controlled, double blind, randomized trial was performed.

Results

In patients with NF1, lovastatin revealed significant decrease of intracortical inhibition, significant increase of synaptic plasticity as well as significant increase of phasic alertness. Compared to HC, patients with NF1 exposed increased intracortical inhibition, impaired synaptic plasticity and deficits in phasic alertness.

Conclusions

This study demonstrates, for the first time, a link between a pathological RAS pathway activity, intracortical inhibition and impaired synaptic plasticity and its rescue by lovastatin in humans. Our findings revealed mechanisms of attention disorders in humans with NF1 and support the idea of a potential clinical benefit of lovastatin as a therapeutic option.

Simultaneous quantitation of atorvastatin and its two active metabolites in human plasma by liquid chromatography/(-) electrospray tandem mass spectrometry

A sensitive, accurate and selective liquid chromatography–tandem mass spectrometry method (LC–MS/MS) was developed and validated for the simultaneous quantitation of atorvastatin (AT) and its equipotent hydroxyl metabolites, 2-hydroxy atorvastatin (2-AT) and 4-hydroxy atorvastatin (4-AT), in human plasma. Electrospray ionization (ESI) interface in negative ion mode was selected to improve the selectivity and the sensitivity required for this application. Additionally, a solid phase extraction (SPE) step was performed to reduce any ion-suppression and/or enhancement effects. The separation of all compounds was achieved in less than 6 min using a C₁₈ reverse-phase fused-core^® column and a mobile phase, composed of a mixture of 0.005% formic acid in water:acetonitrile:methanol (35:25:40, v/v/v), in isocratic mode at a flow rate of 0.6 mL/min. The method has lower limit of quantitation (LLOQ) of 0.050 ng/mL for all analytes. The method has shown tremendous reproducibility, with intra- and inter-day precision less than 6.6%, and intra- and inter-day accuracy within ±4.3% of nominal values, for all analytes, and has proved to be highly reliable for the analysis of clinical samples.

Transporters and drug-drug interactions: important determinants of drug disposition and effects

Uptake and efflux transporters determine plasma and tissue concentrations of a broad variety of drugs. They are localized in organs such as small intestine, liver, and kidney, which are critical for drug absorption and elimination. Moreover, they can be found in important blood-tissue barriers such as the blood-brain barrier. Inhibition or induction of drug transporters by coadministered drugs can alter pharmacokinetics and pharmacodynamics of the victim drugs. This review will summarize in particular clinically observed drug-drug interactions attributable to inhibition or induction of intestinal export transporters [P-glycoprotein (P-gp), breast cancer resistance protein (BCRP)], to inhibition of hepatic uptake transporters [organic anion transporting polypeptides (OATPs)], or to inhibition of transporter-mediated [organic anion transporters (OATs), organic cation transporter 2 (OCT2), multidrug and toxin extrusion proteins (MATEs), P-gp] renal secretion of xenobiotics. Available data on the impact of nutrition on transport processes as well as genotype-dependent, transporter-mediated drug-drug interactions will be discussed. We will also present and discuss data on the variable extent to which information on the impact of transporters on drug disposition is included in summaries of product characteristics of selected countries (SPCs). Further work is required regarding a better understanding of the role of the drug metabolism-drug transport interplay for drug-drug interactions and on the extrapolation of in vitro findings to the in vivo (human) situation.

Simvastatin ameliorates cauda equina compression injury in a rat model of lumbar spinal stenosis

Lumbar spinal stenosis (LSS) is the leading cause of morbidity and mortality worldwide. LSS pathology is associated with secondary injury caused by inflammation, oxidative damage and cell death. Apart from laminectomy, pharmacological therapy targeting secondary injury is limited. Statins are FDA-approved cholesterol-lowering drug. They also show pleiotropic anti-inflammatory, antioxidant and neuroprotective effects. To investigate the therapeutic efficacy of simvastatin in restoring normal locomotor function after cauda equina compression (CEC) in a rat model of LSS, CEC injury was induced in rats by implanting silicone gels into the epidural spaces of L4 and L6. Experimental group was treated with simvastatin (5 mg/kg body weight), while the injured (vehicle) and sham operated (sham) groups received vehicle solution. Locomotor function in terms of latency on rotarod was measured for 49 days and the threshold of pain was determined for 14 days. Rats were sacrificed on day 3 and 14 and the spinal cord and cauda equina fibers were extracted and studied by histology, immunofluorescence, electron microscopy (EM) and TUNEL assay. Simvastatin aided locomotor functional recovery and enhanced the threshold of pain after the CEC. Cellular Infiltration and demyelination decreased in the spinal cord from the simvastatin group. EM revealed enhanced myelination of cauda equina in the simvastatin group. TUNEL assay showed significantly decreased number of apoptotic neurons in spinal cord from the simvastatin group compared to the vehicle group. Simvastatin hastens the locomotor functional recovery and reduces pain after CEC. These outcomes are mediated through the neuroprotective and anti-inflammatory properties of simvastatin. The data indicate that simvastatin may be a promising drug candidate for LSS treatment in humans.

Effect of simvastatin on passive strain-induced skeletal muscle injury in rats

INTRODUCTION

HMG-CoA reductase inhibitors are the most frequently prescribed drugs for treatment of lipid imbalance, but they have side effects, such as myopathy. Our aim was to assess the effect of simvastatin on the inflammatory process induced by skeletal muscle injury.

METHODS

Rats were divided into experimental groups [control group, simvastatin (20 mg/kg) group, group treated with simvastatin (20 mg/kg) and subjected to injury, and group subjected to injury only]. Histological analysis and analyses of creatine kinase activity and C-reactive protein were performed.

RESULTS

Animals treated with simvastatin exhibited significantly greater morphological and structural skeletal muscle damage in comparison to the control group and injured animals without treatment.

CONCLUSIONS

Although simvastatin has a small anti-inflammatory effect in the early stage after a muscle strain injury, the overall picture is negative, as simvastatin increases the extent of damage to muscle morphology. Further studies are needed.

Statin intake is associated with decreased insulin sensitivity during cardiac surgery

OBJECTIVE

Surgical trauma impairs intraoperative insulin sensitivity and is associated with postoperative adverse events. Recently, preprocedural statin therapy is recommended for patients with coronary artery disease. However, statin therapy is reported to increase insulin resistance and the risk of new-onset diabetes. Thus, we investigated the association between preoperative statin therapy and intraoperative insulin sensitivity in nondiabetic, dyslipidemic patients undergoing coronary artery bypass grafting.

RESEARCH DESIGN AND METHODS

In this prospective, nonrandomized trial, patients taking lipophilic statins were assigned to the statin group and hypercholesterolemic patients not receiving any statins were allocated to the control group. Insulin sensitivity was assessed by the hyperinsulinemic-normoglycemic clamp technique during surgery. The mean, SD of blood glucose, and the coefficient of variation (CV) after surgery were calculated for each patient. The association between statin use and intraoperative insulin sensitivity was tested by multiple regression analysis.

RESULTS

We studied 120 patients. In both groups, insulin sensitivity gradually decreased during surgery with values being on average ∼20% lower in the statin than in the control group. In the statin group, the mean blood glucose in the intensive care unit was higher than in the control group (153 ± 20 vs. 140 ± 20 mg/dL; P < 0.001). The oscillation of blood glucose was larger in the statin group (SD, P < 0.001; CV, P = 0.001). Multiple regression analysis showed that statin use was independently associated with intraoperative insulin sensitivity (β = -0.16; P = 0.03).

CONCLUSIONS

Preoperative use of lipophilic statins is associated with increased insulin resistance during cardiac surgery in nondiabetic, dyslipidemic patients.

Comparison of arterial remodeling and changes in plaque composition between patients with progression versus regression of coronary atherosclerosis during statin therapy (from the TRUTH study)

Statin therapy produces regression of coronary artery plaques and reduces the incidence of coronary artery disease. However, not all patients show regression of coronary atherosclerosis after statin therapy. The purpose of the present study was to identify differences in clinical characteristics, serum lipid profiles, arterial remodeling, and plaque composition between patients with progression and those with regression of coronary atherosclerosis during statin therapy. The effects of 8-month statin therapy on coronary atherosclerosis were evaluated in the Treatment With Statin on Atheroma Regression Evaluated by Intravascular Ultrasound With Virtual Histology (TRUTH) study using intravascular ultrasound-virtual histology. One hundred nineteen patients were divided into 2 groups according to atheroma volume increase (progressors) or decrease (regressors) during an 8-month follow-up period. Fifty-one patients (43%) were categorized as progressors and the remaining 68 (57%) as regressors. External elastic membrane volume increased, although not significantly (0.8%, p = 0.34), and luminal volume decreased significantly (-5.3%, p = 0.0003) in progressors, while external elastic membrane volume decreased significantly (-3.2%, p <0.0001) and luminal volume increased (2.2%, p = 0.13) in regressors. The fibrous component increased significantly in progressors, while this component decreased in regressors. A strong positive correlation was observed between change in atheroma volume and change in fibrous volume (r = 0.812, p <0.0001). In conclusion, coronary arteries showed negative remodeling during statin-induced plaque regression. The difference in plaque composition between patients with progression and those with regression of coronary atherosclerosis during statin therapy arose from the difference in the change in fibrous component.

Statin treatment for coronary artery plaque composition based on intravascular ultrasound radiofrequency data analysis

BACKGROUND

Systemic therapy with statin has been shown to lower the risk of coronary events; however, the in vivo effects of statin therapy on plaque volume and composition are less understood.

METHODS

We conducted a prospective, open-labeled, randomized, multicenter study in 11 centers in Japan. A total of 164 patients were randomized to receive either 4 mg/d of pitavastatin (intensive lipid-lowering therapy) or 20 mg/d of pravastatin (moderate lipid-lowering therapy). Analyzable intravascular ultrasound data were obtained for 119 patients at baseline and at 8-month follow-up. The primary end point was the difference of volume changes in each of the 4 main plaque components (fibrosis, fibrofatty, calcium, and necrosis), assessed by virtual histology intravascular ultrasound, between the 2 groups.

RESULTS

The mean low-density lipoprotein cholesterol level at follow-up was significantly lower in the pitavastatin than in the pravastatin group (74 vs 95 mg/dL, P < .0001). During the 8-month follow-up period, statin therapy reduced the absolute and relative amount of fibrofatty component (pitavastatin: from 1.09 to 0.81 mm(3)/mm, P = .001; pravastatin: from 1.05 to 0.83 mm(3)/mm, P = .0008) and increased in the amount of calcium (pitavastatin: from 0.42 to 0.55 mm(3)/mm, P < .0001; pravastatin: from 0.44 to 0.55 mm(3)/mm, P = .005), whereas volume changes in both plaque components were not statistically different between the 2 groups.

CONCLUSIONS

Both pitavastatin and pravastatin altered coronary artery plaque composition by significantly decreasing the fibrofatty plaque component and increasing the calcified plaque component.

No adverse effects of statins on muscle function and health-related parameters in the elderly: an exercise study

The aim of the present study was to investigate the effects of a repeated bout of eccentric exercise on health-related parameters and muscle performance on subjects undergoing atorvastatin therapy. Twenty-eight elderly men participated in the investigation and were assigned either in a control (n = 14) or in a statin therapy group (n = 14). All participants performed two isokinetic eccentric exercise bouts separated by 3 weeks. Muscle damage indices, resting energy expenditure, substrate metabolism, lipid and lipoprotein profile, as well as insulin sensitivity, were evaluated before and after eccentric. No differences in muscle function were observed between the two groups either at rest or after exercise. Eccentric exercise increased resting energy expenditure, increased fat oxidation, improved lipid profile, and increased insulin resistance 2 days after both eccentric exercise bouts. However, these changes appeared to lesser extent after the second bout. No differences were observed in the responses in the health-related parameters in the control and in the statin therapy group. Eccentric exercise affected similarly the control and the atorvastatin-treated individuals. The present results indicate that atorvastatin-treated elderly individuals may participate in various physical activities, even high-intensity muscle-damaging activities, without negative impact on muscle function and adaptation.

Clinical implications of changes in hepatic drug metabolism in older people

Prescribing for older people is challenging because of the paucity of clinical trial evidence of therapeutic benefit in this population and the presence of evidence that older people are at increased risk of adverse drug reactions. The outcomes of pharmacotherapies in older people depend on age-related changes in both pharmacokinetics and pharmacodynamics. Of the pharmacokinetic changes, those in hepatic metabolism are the most significant. Recent advances in biogerontology have improved our understanding of changes that occur in hepatic pharmacokinetics in older people. Knowledge of age-related changes in hepatic metabolism can guide prescribing and help reduce the risk–benefit ratio of using medications in older people.

Chronic obstructive pulmonary disease: patho-physiology, current methods of treatment and the potential for simvastatin in disease management

INTRODUCTION

Chronic Obstructive Pulmonary Disease (COPD) is a severe disease that leads to a non-reversible obstruction of the small airways. The prevalence of this disease is rapidly increasing in developed countries, and in 2020 it has been predicted that this disease will reach the third cause of mortality worldwide. COPD patients do not respond well to current treatment modalities, such as bronchodilators and corticosteroids.

AREAS COVERED

This review article focuses on the patho-physiology of COPD, explores current approaches to alleviate and treat the disease, and discusses the potential use of statins for treatment. Specifically, the mechanism of action and metabolism of simvastatin, the most known and studied molecule among the statin family, are critically reviewed.

EXPERT OPINION

Various cellular pathways have been implicated in COPD, with alveolar macrophages emerging as pivotal inflammatory mediators in the COPD patho-physiology. Recently, emerging anti-cytokine therapies, such as PDE4 inhibitors and ACE inhibitors, have shown good anti-inflammatory properties that can be useful in COPD treatment. Recently, statins as a drug class have gained much interest with respect to COPD management, following studies which show simvastatin to exert effective anti-inflammatory effects, via inhibition of the mevalonic acid cascade in alveolar macrophages.

Statins reduce the androgen sensitivity and cell proliferation by decreasing the androgen receptor protein in prostate cancer cells

BACKGROUND

Statins (3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors) are cholesterol-lowering drugs that are widely used to prevent and treat atherosclerotic cardiovascular disease. Recent epidemiological studies suggest that statins reduce serum prostate-specific antigen (PSA) levels and decrease the risk of prostate cancer. In the present study, we determined the molecular mechanisms related to the regulation of PSA, androgen receptor (AR) and cell proliferation in prostate cancer cell lines by statins.

METHODS

Western blotting, quantitative real-time polymerase chain reaction, cytotoxicity analysis and a cell proliferation assay were used to resolve the regulatory role of statins (mevastatin and simvastatin) in three prostate cancer cell lines, RWPE-1, 22Rv1, and LNCaP.

RESULTS

Western blotting revealed that both mevastatin and simvastatin downregulated AR and PSA protein. However, these statins did not downregulate AR mRNA expression, while they decreased PSA mRNA. The protease inhibitor MG132 inhibited the downregulation of AR protein which suggested that statins decreased AR protein levels by increasing AR proteolysis. Furthermore, statins reduced cell proliferation in AR positive cells but not in AR negative cells, suggesting that statins regulate cell proliferation via AR expression. In addition, cell proliferation assay at various concentrations of dihydrotestosterone (DHT) showed that statins decreased androgen sensitivity in LNCaP cells.

CONCLUSIONS

Statins decreased AR protein by proteolysis but not mRNA transcription. The drop in AR levels resulted in a reduction in androgen sensitivity and a decrease in cell proliferation in AR positive prostate cancer cells.

Impairment of the left ventricular systolic and diastolic function in patients with non-alcoholic fatty liver disease

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is considered the liver component of the metabolic syndrome. We investigated the diastolic and systolic functional parameters of patients with NAFLD and the impact of metabolic syndrome on these parameters.

METHODS

Thirty-five non-diabetic, normotensive NAFLD patients, and 30 controls, were included in this study. Each patient underwent transthoracic conventional and tissue Doppler echocardiography (TDI) for the assessment of left ventricular (LV) diastolic and systolic function. Study patients were also evaluated with 24-hour ambulatory blood pressure monitoring.

RESULTS

NAFLD patients had higher blood pressures, increased body mass indices, and more insulin resistance than controls. TDI early diastolic velocity (E' on TDI) values were lower in NAFLD patients than the controls (11.1 ± 2.1 vs 15.3 ± 2.7; p < 0.001). TDI systolic velocity (S' on TDI) values were lower in NAFLD patients than the controls (9.34 ± 1.79 vs 10.6 ± 1.52; p = 0.004). E' on TDI and S' on TDI values were moderately correlated with night-systolic blood pressure, night-diastolic blood pressure, and night-mean blood pressure in NAFLD patients.

CONCLUSIONS

Patients with NAFLD have impaired LV systolic and diastolic function even in the absence of morbid obesity, hypertension, or diabetes.

New Drug Approvals: Pitavastatin: A New HMG-CoA Reductase Inhibitor

Objective:

To review pitavastatin, the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor and determine its place in the treatment of hypercholesterolemia.

Data Sources:

Literature was accessed through PubMed (1948–December 2009). Pitavastatin, itavastatin, nisvastatin, NK 104, and NKS 104 were used as search terms. Results were limited to articles written in the English language.

Study Selection And Data Extraction:

All articles identified from the data source were reviewed for inclusion. Articles included were those pertaining to the pharmacology and pharmacokinetic properties of pitavastatin, in addition to original research evaluating the clinical efficacy of pitavastatin for hypercholesterolemia.

Data Synthesis:

Pitavastatin is an oral HMG-CoA reductase inhibitor recently approved by the Food and Drug Administration for the treatment of primary hyperlipidemia and mixed dyslipidwmia. Pitavastatin 2 mg has been shown to be noninferior to atorvastatin 10 mg and simvastatin 20 mg with respect to low-density lipoprotein cholesterol (LDL-C)–lowering ability. Additionally, pitavastatin 2 mg was shown in one study to lower LDL-C significantly more than pravastatin 10 mg. As with other HMG-CoA reductase inhibitors, primary safety concerns are related to myopathies and alterations in liver enzyme levels. While efficacy regarding beneficial effects on lipid parameters is comparable to that of other agents, a potential advantage of pitavastatin is its cytochrome P450 (CYP450) independent elimination, thereby reducing the likelihood of clinically significant drug-drug interactions. However, this is not a unique property, as pravastatin and rosuvastatin also possess this property.

Conclusions:

In light of the lack of outcome data, pitavastatin offers no clear advantage over other drugs in this class.

Comparative Efficacy and Safety of Low-Dose Pitavastatin Versus Atorvastatin in Patients with Hypercholesterolemia

Background:

Previous studies have shown conflicting results on low-density lipoprotein cholesterol (LDL-C) reduction for comparable doses of pitsvastatin and atorvastatin.

Objective:

To compare the efficacy of pitavastatin 1 mg once daily with that of atorvastatin 10 mg once daily on lipoprotein change, safety, and cost per percent LDL-C reduction.

Methods:

An 8-week, randomized, open-label, parallel trial was conducted in patients with hypercholesterolemia. One hundred patients were equally randomized to receive pitavastatin 1 mg once daily or atorvastatin 10 mg once daily; 98 completed the study. Outcomes were assessed at baseline and at the end of the study.

Results:

Pitavastatin lowered LDL-C levels from baseline by 37% compared with 46% in the atorvastatin group (p < 0.001). The reduction of total cholesterol (TC) levels from baseline was significantly different between the pitavastatin (28%) and atorvastatin (32%) groups (p = 0.005). There was no significant difference in the percentage of changes in triglyceride and high-density lipoprotein cholesterol levels between groups. The percentage of patients who achieved LDL-C goals according to National Cholesterol Education Program–Adult Treatment Panel III guidelines was not significantly different between the pitavastatin (74%) and atorvastatin (84%) groups (p = 0.220). In addition, both regimens were well tolerated, with no patient developing an elevation of more than 3 times the upper normal limit of alanine aminotransferase or 10 times that of creatine kinase. The monthly cost per percent LDL-C reduction in the pitavastatin group ($0.77) was about 50% lower than the cost in the atorvastatin ($1.56) group.

Conclusions:

Although pitavastatin 1 mg daily was not as effective at lowering LDL-C and TC levels as atorvastatin 10 mg daily, the number of patients achieving their LDL-C goals with pitavastatin was comparable with the number using atorvastatin. Pitavastatin 1 mg once daily may be an alternative regimen with cost-saving benefits but without a significant decrease in therapeutic benefit or increase in adverse events in patients with hypercholesterolemia.

Protein extraction of formalin-fixed, paraffin-embedded tissue enables robust proteomic profiles by mass spectrometry

Global mass spectrometry (MS) profiling and spectral count quantitation are used to identify unique or differentially expressed proteins and can help identify potential biomarkers. MS has rarely been conducted in retrospective studies, because historically, available samples for protein analyses were limited to formalin-fixed, paraffin-embedded (FFPE) archived tissue specimens. Reliable methods for obtaining proteomic profiles from FFPE samples are needed. Proteomic analysis of these samples has been confounded by formalin-induced protein cross-linking. The performance of extracted proteins in a liquid chromatography tandem MS format from FFPE samples and extracts from whole and laser capture microdissected (LCM) FFPE and frozen/optimal cutting temperature (OCT)-embedded matched control rat liver samples were compared. Extracts from FFPE and frozen/OCT-embedded livers from atorvastatin-treated rats were further compared to assess the performance of FFPE samples in identifying atorvastatin-regulated proteins. Comparable molecular mass representation was found in extracts from FFPE and OCT-frozen tissue sections, whereas protein yields were slightly less for the FFPE sample. The numbers of shared proteins identified indicated that robust proteomic representation from FFPE tissue and LCM did not negatively affect the number of identified proteins from either OCT-frozen or FFPE samples. Subcellular representation in FFPE samples was similar to OCT-frozen, with predominantly cytoplasmic proteins identified. Biologically relevant protein changes were detected in atorvastatin-treated FFPE liver samples, and selected atorvastatin-related proteins identified by MS were confirmed by Western blot analysis. These findings demonstrate that formalin fixation, paraffin processing, and LCM do not negatively impact protein quality and quantity as determined by MS and that FFPE samples are amenable to global proteomic analysis.

Population pharmacokinetics of rosuvastatin: implications of renal impairment, race, and dyslipidaemia

OBJECTIVES

To build the structural model of pharmacokinetics for rosuvastatin and evaluate the impact of demographic characteristics including renal function on its pharmacokinetic parameters.

METHODS

A population pharmacokinetic analysis of rosuvastatin in healthy volunteers, subjects with dyslipidaemia, and renal failure patients was performed using non-linear mixed-effects modelling and a two-compartment pharmacokinetic model with simultaneous first- and zero-order absorption. Demographic covariates, dyslipidaemic state and renal function were evaluated for their impact on pharmacokinetic parameters by step-wise additions or deletions using the likelihood ratio test.

RESULTS

Typical pharmacokinetic parameters were estimated for a healthy white male subject. For example, apparent oral clearance (CL/F) was estimated to be 257 L/h. Age, smoking status, weight, body surface area, and lean body mass had no significant effect on rosuvastatin pharmacokinetics. The model predicted that CL/F for subjects with creatinine clearance (CLCR) of 30 mL/min (moderate renal impairment) and of 50 mL/min (mild renal impairment) was 17% and 9.7% lower, respectively, relative to subjects with CLCR of 94 mL/min, the data set median value. CL/F was reduced by 71.1% and 43.7% in subjects with dyslipidaemia and in Asian subjects, respectively.

CONCLUSIONS

Reduction of CL/F of rosuvastatin is not considered clinically significant for patients with mild-to-moderate renal impairment. Rosuvastatin CL/F was reduced in subjects with dyslipidaemia, but it is important to realise that the safety/efficacy profile of rosuvastatin has been well established in this population. However, the potential for increased exposure in Asian subjects should be considered when initiating rosuvastatin treatment or increasing dose in this population.

Statins and prostate cancer prevention: where we are now, and future directions

Statins are cholesterol-lowering drugs that are widely used to prevent and treat atherosclerotic cardiovascular disease. Recent research from both in vitro and in vivo studies suggests that there is an association between the use of statins and a reduction in the incidence of and mortality from prostate cancer. Several mechanisms of action that might bring about these beneficial effects of statins have been proposed, most of which include direct effects of statins on intracellular signaling. In this Review we discuss the current knowledge on the use of statins to prevent prostate cancer. We will also look at future directions for clinical research on this topic.