Statin-associated myopathy and the quest for biomarkers: can we effectively predict statin-associated muscle symptoms?

Mevalonate in blood and muscle: Response to atorvastatin treatment and the relationship to statin intolerance in patients with coronary heart disease

Statin-associated muscle symptoms are frequently reported and often lead to discontinuation of statin therapy with an increased risk of cardiovascular events. In vitro studies suggest that statin-mediated inhibition of the mevalonate pathway leads to muscle cell toxicity. We aimed to determine the relationship between mevalonate, LDL-cholesterol, and atorvastatin metabolites in patients with coronary heart disease and self-perceived muscle side effects. Furthermore, we assessed the correlation between mevalonate in blood and muscle and the relationship to statin intolerance due to muscle symptoms. We used blood plasma from a randomized crossover trial (n = 70) and muscle biopsies and plasma from a subgroup in a subsequent open intervention study (n = 26). Both studies tested atorvastatin 40 mg/day. Seven patients did not tolerate ≥3 statins throughout the follow-up and were classified as statin-intolerant. Mevalonate in blood plasma decreased during atorvastatin treatment (median difference -38%, range -77% to 43%, p < 0.001), whereas mevalonate in muscle tissue was not lowered (0.05%, range -47% to 145%). Mevalonate correlated poorly with LDL-cholesterol and atorvastatin metabolites (Spearman's rho -0.28 to 0.10). The statin-intolerant patients had a smaller reduction in circulating mevalonate compared with the tolerant patients; median difference -8.1 (-22 to 3.5) nmol/L versus -25 (-93 to 12) nmol/L, p = 0.028. A similar observation was made for LDL-cholesterol. Cutoffs based on these biomarkers classified >50% correctly as tolerant. Inhibition of the mevalonate pathway does not appear to be the mechanism underlying statin intolerance in the present study. Further studies of mevalonate as a biomarker for statin tolerance are needed to clarify the potential.

Molecular Mechanisms Affecting Statin Pharmacokinetics after Bariatric Surgery

According to recent data, one in eight people in the world struggle with obesity. Obesity management is increasingly dependent on bariatric surgical interventions, as the combination of lifestyle modifications and pharmacotherapy could have a modest long-term effect. Surgery is recommended only for individuals whose body mass index (BMI) ≥ 40 kg/m2 and ≥ 35 kg/m2 in the presence of weight-related comorbidities. The most commonly performed procedures are sleeve gastrectomy and roux-en-Y gastric bypass. Pharmacokinetic and pharmacodynamic alterations occur as a result of the anatomical and physiological changes caused by surgery, which further differ depending on physicochemical drug factors and factors related to the dosage form. The following modifications are distinguished based on the type of bariatric surgery performed. Most bariatric patients have accompanying comorbidities, including dyslipidemia treated with hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors or statins. Significant improvements in the lipid profile are observed early in the postoperative period. The data reported in this review on statin pharmacokinetic alterations have demonstrated substantial inter- and intravariability, making it difficult to adopt clear guidelines. Based on the current literature review, reducing the statin dose to the lowest effective with continuous monitoring is considered an optimal approach in clinical practice.

Chenodeoxycholic Acid-Modified Polyethyleneimine Nano-Composites Deliver Low-Density Lipoprotein Receptor Genes for Lipid-Lowering Therapy by Targeting the Liver

Lipid-lowering drugs, especially statins, are extensively utilized in clinical settings for the prevention of hyperlipidemia. Nevertheless, prolonged usage of current lipid-lowering medications is associated with significant adverse reactions. Therefore, it is imperative to develop novel therapeutic agents for lipid-lowering therapy. In this study, a chenodeoxycholic acid and lactobionic acid double-modified polyethyleneimine (PDL) nanocomposite as a gene delivery vehicle for lipid-lowering therapy by targeting the liver, are synthesized. Results from the in vitro experiments demonstrate that PDL exhibits superior transfection efficiency compared to polyethyleneimine in alpha mouse liver 12 (AML12) cells and effectively carries plasmids. Moreover, PDL can be internalized by AML12 cells and rapidly escape lysosomal entrapment. Intravenous administration of cyanine5.5 (Cy5.5)-conjugated PDL nanocomposites reveals their preferential accumulation in the liver compared to polyethyleneimine counterparts. Systemic delivery of low-density lipoprotein receptor plasmid-loaded PDL nanocomposites into mice leads to reduced levels of low-density lipoprotein cholesterol (LDL-C) and triglycerides (TC) in the bloodstream without any observed adverse effects on mouse health or well-being. Collectively, these findings suggest that low-density lipoprotein receptor plasmid-loaded PDL nanocomposites hold promise as potential therapeutics for lipid-lowering therapy.

Research advances in the therapy of metabolic syndrome

Metabolic syndrome refers to the pathological state of metabolic disorder of protein, fat, carbohydrate, and other substances in the human body. It is a syndrome composed of a group of complex metabolic disorders, whose pathogenesis includes multiple genetic and acquired entities falling under the category of insulin resistance and chronic low-grade inflammationand. It is a risk factor for increased prevalence and mortality from diabetes and cardiovascular disease. Cardiovascular diseases are the predominant cause of morbidity and mortality globally, thus it is imperative to investigate the impact of metabolic syndrome on alleviating this substantial disease burden. Despite the increasing number of scientists dedicating themselves to researching metabolic syndrome in recent decades, numerous aspects of this condition remain incompletely understood, leaving many questions unanswered. In this review, we present an epidemiological analysis of MetS, explore both traditional and novel pathogenesis, examine the pathophysiological repercussions of metabolic syndrome, summarize research advances, and elucidate the mechanisms underlying corresponding treatment approaches.

Interplay of OATP1A/1B/2B1 uptake transporters and ABCB1 and ABCG2 efflux transporters in the handling of bilirubin and drugs

Transmembrane drug transporters can be important determinants of the pharmacokinetics, efficacy, and safety profiles of drugs. To investigate the potential cooperative and/or counteracting interplay of OATP1A/1B/2B1 uptake transporters and ABCB1 and ABCG2 efflux transporters in physiology and pharmacology, we generated a new mouse model (Bab12), deficient for Slco1a/1b, Slco2b1, Abcb1a/1b and Abcg2. Bab12 mice were viable and fertile. We compared wild-type, Slco1a/1b/2b1-/-, Abcb1a/1b;Abcg2-/- and Bab12 strains. Endogenous plasma conjugated bilirubin levels ranked as follows: wild-type = Abcb1a/1b;Abcg2-/- << Slco1a/1b/2b1-/- < Bab12 mice. Plasma levels of rosuvastatin and fexofenadine were elevated in Slco1a/1b/2b1-/- and Abcb1a/1b;Abcg2-/- mice compared to wild-type, and dramatically increased in Bab12 mice. Although systemic exposure of larotrectinib and repotrectinib was substantially increased in the separate multidrug transporter knockout strains, no additive effects were observed in the combination Bab12 mice. Significantly higher plasma exposure of fluvastatin and pravastatin was only found in Slco1a/1b/2b1-deficient mice. However, noticeable transport by Slco1a/1b/2b1 and Abcb1a/1b and Abcg2 across the BBB was observed for fluvastatin and pravastatin, respectively, by comparing Bab12 mice with Abcb1a/1b;Abcg2-/- or Slco1a/1b/2b1-/- mice. Quite varying behavior in plasma exposure of erlotinib and its metabolites was observed among these strains. Bab12 mice revealed that Abcb1a/1b and/or Abcg2 can contribute to conjugated bilirubin elimination when Slco1a/1b/2b1 are absent. Our results suggest that the interplay of Slco1a/1b/2b1, Abcb1a/1b, and Abcg2 could markedly affect the pharmacokinetics of some, but not all drugs and metabolites. The Bab12 mouse model will represent a useful tool for optimizing drug development and clinical application, including efficacy and safety.

Drug-Induced Myopathies: A Comprehensive Review and Update

Drug-induced myopathies are a common cause of muscle pain, and the range of drugs that can cause muscle side effects is constantly expanding. In this article, the authors comprehensively discuss the diagnostic and therapeutic process in patients with myalgia, and present the spectrum of drug-induced myopathies. The review provides a detailed analysis of the literature on the incidence of myopathy during treatment with hypolipemic drugs, beta-blockers, amiodarone, colchicine, glucocorticosteroids, antimalarials, cyclosporine, zidovudine, and checkpoint inhibitors, a group of drugs increasingly used in the treatment of malignancies. The article considers the clinical course of the different types of myopathies, their pathogenesis, histopathological features, and treatment methods of these disorders. The aim of this paper is to gather from the latest available literature up-to-date information on the course, pathophysiology, and therapeutic options of drug-induced myopathies, to systematize the knowledge of drug-induced myopathies and to draw the attention of internists to the fact that these clinical issues are an important therapeutic problem.

Statins-From Fungi to Pharmacy

Statins have been used in the treatment of hyperlipidemia, both as monotherapy and in combination therapy. Natural fermentation processes of fungi such as Monascus spp., Penicillium spp., Aspergillus terreus, and Pleurotus ostreatus have given rise to natural statins. Compactin (mevastatin), the original naturally occurring statin, is the primary biotransformation substrate in the manufacturing process of marketed drugs. Statins are classified into natural, semi-synthetic derivatives of natural statins, and synthetic ones. Synthetic statins differ from natural statins in their structural composition, with the only common feature being the HMG-CoA-like moiety responsible for suppressing HMG-CoA reductase. Statins do not differ significantly regarding their pleiotropic and adverse effects, but their characteristics depend on their pharmacokinetic parameters and chemical properties. This paper focuses on describing the processes of obtaining natural statins, detailing the pharmacokinetics of available statins, divided into natural and synthetic, and indicating their pleiotropic effects.

Genetic polymorphisms in ABCB1 are correlated with the increased risk of atorvastatin-induced muscle side effects: a cross-sectional study

Genetic factors are recognized as risk factors for statin-associated muscle symptoms (SAMS), which are the most common cause of statin intolerance. The aim of this study was to determine whether there is an association between polymorphisms 1236C > T, 2677G > T/A, and 3435C > T in the ABCB1 gene, encoding the efflux transporter of statins, and SAMS, as results on this topic are still controversial. A cross-sectional study was conducted on patients with or without SAMS using atorvastatin. The influence of non-genetic variables on SAMS was also evaluated. Our results show that patients with TT genotype in 1236C > T, 2677G > T/A, and 3435C > T polymorphisms had higher risk of developing SAMS, compared to wild type and heterozygous carriers together (OR 4.292 p = 0.0093, OR 5.897 p = 0.0023 and OR 3.547 p = 0.0122, respectively). Furthermore, TTT/TTT diplotype was also associated with a higher risk of SAMS, OR 9.234 (p = 0.0028). Only family history of cardiovascular disease was found to be a risk factor for SAMS, in addition to the known non-genetic variables. We believe that ABCB1 genotyping has great potential to be incorporated into clinical practice to identify high-risk patients in a timely manner.

An overview on nanoplatforms for statins delivery: Perspectives for safe and effective therapy

Statins are the most widely used pharmacological agents for reducing blood cholesterol levels and treating atherosclerotic cardiovascular diseases. Most of the statins' derivatives have been limited by water solubility, bioavailability, and oral absorption, which has led to adverse effects on several organs, especially at high doses. As an approach to reducing statin intolerance, achieving a stable formulation with improved efficacy and bioavailability at low doses has been suggested. Nanotechnology-based formulations may provide a therapeutic benefit over traditional formulations in terms of potency and biosafety. Nanocarriers can provide tailored delivery platforms for statins, thereby enhancing the localized biological effects and lowering the risk of undesired side effects while boosting statin's therapeutic index. Furthermore, tailored nanoparticles can deliver the active cargo to the desired site, which culminates in reducing off-targeting and toxicity. Nanomedicine could also provide opportunities for therapeutic methods by personalized medicine. This review delves into the existing data on the potential improvement of statin therapy using nano-formulations.

A mobile health application for patients eligible for statin therapy: app development and qualitative feedback on design and usability

BACKGROUND

Cardiovascular disease is the leading cause of death in the United States (US). Despite the well-recognized efficacy of statins, statin discontinuation rates remain high. Statin intolerance is a major cause of statin discontinuation. To accurately diagnose statin intolerance, healthcare professionals must distinguish between statin-associated and non-statin-associated muscle symptoms, because many muscle symptoms can be unrelated to statin therapy. Patients' feedback on muscle-related symptoms would help providers make decisions about statin treatment. Given the potential benefits and feasibility of existing apps for cardiovascular disease (CVD) management and the unmet need for an app specifically addressing statin intolerance management, the objectives of the study were 1) to describe the developmental process of a novel app designed for patients who are eligible for statin therapy to lower the risk of CVD; 2) to explore healthcare providers' feedback of the app; and 3) to explore patients' app usage experience.

METHODS

The app was developed by an interdisciplinary team. Healthcare provider participants and patient participants were recruited in the study. Providers were interviewed to provide their feedback about the app based on screenshots of the app. Patients were interviewed after a 30 days of app usage.

RESULTS

The basic features of the app included symptom logging, vitals tracking, patient education, and push notifications. Overall, both parties provided positive feedback about the app. Areas to be improved mentioned by both parties included: the pain question asked in symptom tracking and the patient education section. Both parties agreed that it was essential to add the trend report of the logged symptoms.

CONCLUSIONS

The results indicated that providers were willing to use patient-reported data for disease management and perceived that the app had the potential to facilitate doctor-patient communication. Results also indicated that user engagement is the key to the success of app efficacy. To promote app engagement, app features should be tailored to individual patient's needs and goals. In the future, after it is upgraded, we plan to test the app usability and feasibility among a more diverse sample.

Effects of Statin Treatment on the Development of Tendinopathy: A Nationwide Population-Based Cohort Study

Background

Previous longitudinal cohort studies have reported the conflicting results of the relationship between statin use and the development of tendinopathy disorder. It is unclear if there is a relationship between statin use, particularly the type or cumulative doses, and the development of tendinopathy disorder.

Purpose

To investigate an association between statin treatment and the development of tendinopathy.

Study Design

Cohort study; Level of evidence, 3.

Methods

A total of 594,130 participants were enrolled in this study in 2002 and evaluated until 2015. There were 84,102 statin users and 168,204 nonusers (controls) selected at a ratio of 1:2 using propensity score matching analysis. The types of included tendinopathy were as follows: (1) trigger finger, (2) radial styloid tenosynovitis, (3) elbow epicondylitis, (4) rotator cuff tendinopathy, and (5) Achilles tendinitis. Cox proportional hazards models with time-varying covariates were constructed to identify the association between statin use and tendinopathy development.

Results

Statin treatments regardless of statin types were associated with a significantly greater risk of all types of tendinopathy development (hazard ratio, 1.435; 95% CI, 1.411-1.460) compared with no statin treatment. A trend toward risk reduction was observed according to cumulative statin doses, which was indicated by hazard ratios of 2.337 (95% CI, 2.269-2.406), 2.210 (95% CI, 2.132-2.290), and 1.1 (95% CI, 1.098-1.146) in patients with cumulative defined daily doses of 90, 91-180, and >180, respectively.

Conclusion

This nationwide population-based cohort study suggests that statin use regardless of the statin type was associated with a greater risk of tendinopathy compared with that of nonusers. The risk of tendinopathy development was diluted with the increasing cumulative defined daily dose.

Developing In Vitro Models to Define the Role of Direct Mitochondrial Toxicity in Frequently Reported Drug-Induced Rhabdomyolysis

The United States Food and Drug Administration Adverse Event Reporting System (FAERS) logged 27,140 rhabdomyolysis cases from 2004 to 31 March 2020. We used FAERS to identify 14 drugs frequently reported in 6583 rhabdomyolysis cases and to investigate whether mitochondrial toxicity is a common pathway of drug-induced rhabdomyolysis by these drugs. Preliminary screening for mitochondrial toxicity was performed using the acute metabolic switch assay, which is adapted here for use in murine L6 cells. Fenofibrate, risperidone, pregabalin, propofol, and simvastatin lactone drugs were identified as mitotoxic and underwent further investigation, using real-time respirometry (Seahorse Technology) to provide more detail on the mechanism of mitochondrial-induced toxicity. To confirm the human relevance of the findings, fenofibrate and risperidone were evaluated in primary human skeletal muscle-derived cells (HSKMDC), using the acute metabolic switch assay and real-time respirometry, which confirmed this designation, although the toxic effects on the mitochondria were more pronounced in HSKMDC. Overall, these studies demonstrate that the L6 model of acute modification may find utility as an initial, cost-effective screen for identifying potential myotoxicants with relevance to humans and, importantly, that drug-induced mitochondrial dysfunction may be a common mechanism shared by some drugs that induce myotoxicity.

The Management of Hypercholesterolemia in Patients with Neuromuscular Disorder

PURPOSE OF REVIEW

We describe and discuss the safety of statins and non-statin drugs in neuromuscular disorders (NMDs). We also propose a pragmatic model of care for the management of such cases.

RECENT FINDINGS

Patients with both NMD and hypercholesterolemia may be particularly disadvantaged owing to the toxic effects of cholesterol-lowering therapy and the inability to take medication. Specifically, the management of hypercholesterolemia in patients with NMD is complicated by the increased risk of statin-related myotoxicity and concerns that statins may aggravate or possibly induce the onset of a specific NMD. The most severe form of statin-related myotoxicity is immune-mediated necrotizing myopathy. Management of hypercholesterolemia in patients with NMDs include treating modifiable factors, consideration of toxicity risk of statin, use of non-statin lipid lowering agents, noting possible drug interactions, and careful monitoring.

Facts and ideas on statins with respect to their lipophilicity: a focus on skeletal muscle cells and bone besides known cardioprotection

Statins are known to block cholesterol synthesis in the liver. They also exhibit non-lipid pleiotropic effects due to the inhibition of protein prenylation, thereby modulating various signaling pathways of cellular homeostasis and integrity. Both lipid control and pleiotropic action of statins are clinically used, mainly for treatment of hypercholesterolemia and primary and secondary prevention of cardiovascular diseases. Because the prescription of statins is increasing and statin therapy is often lifelong, in particular in patients with other risk factors, safety issues being associated with polymorbidity and polypragmasia as well as the persistence with and adherence to statins are specific points of attention of clinicians and clinical pharmacologists. Furthermore, because skeletal myocytes have a cholesterol inhibitory sensitivity greater than hepatocytes, a choice of an appropriate statin based on its lipophilicity and the associated likelihood of its side effects on skeletal muscle cells and bone is warranted in such polymorbid patients. These approaches can effectively modulate the risk: benefit ratio and highlight a need for personalized therapy as much as possible, thereby minimizing risk of discontinuation of therapy and poor compliance.

Mitochondrial Effects of Common Cardiovascular Medications: The Good, the Bad and the Mixed

Mitochondria are central organelles in the homeostasis of the cardiovascular system via the integration of several physiological processes, such as ATP generation via oxidative phosphorylation, synthesis/exchange of metabolites, calcium sequestration, reactive oxygen species (ROS) production/buffering and control of cellular survival/death. Mitochondrial impairment has been widely recognized as a central pathomechanism of almost all cardiovascular diseases, rendering these organelles important therapeutic targets. Mitochondrial dysfunction has been reported to occur in the setting of drug-induced toxicity in several tissues and organs, including the heart. Members of the drug classes currently used in the therapeutics of cardiovascular pathologies have been reported to both support and undermine mitochondrial function. For the latter case, mitochondrial toxicity is the consequence of drug interference (direct or off-target effects) with mitochondrial respiration/energy conversion, DNA replication, ROS production and detoxification, cell death signaling and mitochondrial dynamics. The present narrative review aims to summarize the beneficial and deleterious mitochondrial effects of common cardiovascular medications as described in various experimental models and identify those for which evidence for both types of effects is available in the literature.

Statins Neuromuscular Adverse Effects

Statins are drugs widely prescribed in high-risk patients for cerebrovascular or cardiovascular diseases and are, usually, safe and well tolerated. However, these drugs sometimes may cause neuromuscular side effects that represent about two-third of all adverse events. Muscle-related adverse events include cramps, myalgia, weakness, immune-mediated necrotizing myopathy and, more rarely, rhabdomyolysis. Moreover, they may lead to peripheral neuropathy and induce or unmask a preexisting neuromuscular junction dysfunction. A clinical follow up of patients assuming statins could reveal early side effects that may cause neuromuscular damage and suggest how to better modulate their use. In fact, statin dechallenge or cessation, or the alternative use of other lipid-lowering agents, can avoid adverse events. This review summarizes the current knowledge on statin-associated neuromuscular adverse effects, diagnosis, and management. It is conceivable that the incidence of neuromuscular complications will increase because, nowadays, use of statins is even more diffused than in the past. On this purpose, it is expected that pharmacogenomic and environmental studies will help to timely predict neuromuscular complications due to statin exposure, leading to a more personalized therapeutic approach.

Step-by-step diagnosis and management of the nocebo/drucebo effect in statin-associated muscle symptoms patients: a position paper from the International Lipid Expert Panel (ILEP)

Statin intolerance is a clinical syndrome whereby adverse effects (AEs) associated with statin therapy [most commonly statin-associated muscle symptoms (SAMS)] result in the discontinuation of therapy and consequently increase the risk of adverse cardiovascular outcomes. However, complete statin intolerance occurs in only a small minority of treated patients (estimated prevalence of only 3-5%). Many perceived AEs are misattributed (e.g. physical musculoskeletal injury and inflammatory myopathies), and subjective symptoms occur as a result of the fact that patients expect them to do so when taking medicines (the nocebo/drucebo effect)-what might be truth even for over 50% of all patients with muscle weakness/pain. Clear guidance is necessary to enable the optimal management of plasma in real-world clinical practice in patients who experience subjective AEs. In this Position Paper of the International Lipid Expert Panel (ILEP), we present a step-by-step patient-centred approach to the identification and management of SAMS with a particular focus on strategies to prevent and manage the nocebo/drucebo effect and to improve long-term compliance with lipid-lowering therapy.

Statin-associated muscle symptoms-A review: Individualizing the approach to optimize care

The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, also known as "statins" are considered first-line pharmacologic therapy for reducing low-density lipoprotein cholesterol (LDL-C). They have been demonstrated efficacy in a variety of patients populations to reduce atherosclerotic cardiovascular disease (ASCVD) risk. Like any pharmacologic therapy, however, they are not without possible adverse effects that can lead to discontinuation, thus leading to a loss of benefit. The most common side effect related to statin therapy impacting compliance is musculoskeletal related, commonly referred to as statin-associated muscle systems (SAMS). While the overall incidence is relatively low, the consequences of nonadherence to statin therapy can have a negative impact on patient care. Therefore, it is important for healthcare providers to understand risk factors, how to diagnose, and how to manage this unfortunate adverse effect in order to optimize care.

Dynamic urine proteome changes in a rat model of simvastatin-induced skeletal muscle injury

Statin-associated muscle symptoms (SAMS) are the main side effects of statins. Currently, there are no effective biomarkers for accurate clinical diagnosis. Urine is not subject to homeostatic control and therefore accumulates early changes, making it an ideal biomarker source. We therefore examined urine proteome changes associated with SAMS. Here, we established a SAMS rat model by intragastric intubation with simvastatin (80 mg/kg). Biochemical analyses and hematoxylin and eosin staining were used to evaluate the degree of muscle injury. The urine proteome on days 3, 6, 9 and 14 was profiled using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Differential proteins on day 14 of SAMS were mainly associated with glycolysis/gluconeogenesis, pyruvate metabolism, metabolism of reactive oxygen species and apoptosis, which were associated with the pathological mechanism of SAMS. Among the 14 differential proteins on day 3, Fibrinogen gamma chain (FIBG), Osteopontin (OSTP) and C-reactive protein (CRP) were associated with muscle damage, while EH domain-containing protein 1(EHD1), Cubilin (CUBN) and Fibronectin (FINC) were associated with the pathogenic mechanisms of SAMS. Our preliminary results indicated that the urine proteome can reflect early changes in the SAMS rat model, providing the potential for monitoring drug side effects in future clinical research. SIGNIFICANCE: This study demonstrate that the early muscle damage caused by simvastatin can be reflected in urinary proteins. The urine proteome also has the potential to reflect the pharmacology and toxicology of drugs in future clinical research.

Gynura procumbens ethanol extract improves vascular dysfunction by suppressing inflammation in postmenopausal rats fed a high-fat diet

CONTEXT

Gynura procumbens (Lour.) Merr. (Asteraceae) has been reported to have various pharmacological activities including anti-inflammatory effects.

OBJECTIVE

This study sought to determine whether Gynura procumbens (GP) could improve vascular reactivity by suppressing inflammation in postmenopausal rats fed with five-times heated palm oil (5HPO) diet.

MATERIALS AND METHODS

Forty-eight female Sprague-Dawley rats were randomly divided into sham [non-ovariectomized; grouped as control, GP extracts (250 and 500 mg/kg), atorvastatin (ATV, 10 mg/kg)] and postmenopausal (PM) groups [ovariectomized rats fed with 5HPO; grouped as PM, GP extracts (250 and 500 mg/kg) and ATV (10 mg/kg)]. Each group (n = 6) was either supplemented with GP extract or ATV orally once daily for 6 months.

RESULTS

In comparison with the untreated PM group, 250 and 500 mg/kg GP supplementation to PM groups reduced the systolic blood pressure (103 ± 2.7, 86 ± 2.4 vs. 156 ± 7.83 mmHg, p < 0.05), intima-media thickness (101.28 ± 3.4, 93.91 ± 2.93 vs. 143.78 ± 3.31 µM), vasoconstriction percentage induced by phenylephrine (102.5%, 88.3%, vs. 51.8%), sICAM-1 (0.49, 0.26 vs. 0.56 pg/mL) and sVCAM-1 (0.39, 0.25 vs. 0.45 pg/mL). GP extract supplementation increased vasorelaxation percentage induced by acetylcholine (78.4% vs. 47.3%) and sodium nitroprusside (84.2% vs. 53.7%), increased changes in plasma nitric oxide level (1.25%, 1.31% vs. 1.9%), and suppressed the elevation of TNF-α (0.39 vs. 1.02 pg/mL), IL-6 (0.43 vs. 0.77 pg/mL) and CRP (0.29 vs. 0.69 ng/mL) in the PM groups.

CONCLUSIONS

GP extract might improve vascular dysfunction by suppressing the inflammatory response, consequently preventing blood pressure elevation.

[Diagnostics and treatment of statin-associated muscle symptoms]

Statins are among the most frequently prescribed drugs in Germany. Their benefits in lowering cardiovascular risk are beyond dispute. Nevertheless, many patients complain of side effects from statin therapy, including statin-associated muscle symptoms (SAMS) in particular. Despite their relative frequency, it is difficult to objectively diagnose them, as the time until appearance of first symptoms, the nature of the complaints and the severity of muscle problems vary widely. This narrative review summarizes the causes of SAMS as well as new possibilities regarding their diagnosis and therapy.

Hydrophilic or Lipophilic Statins?

Drugs can be classified as hydrophilic or lipophilic depending on their ability to dissolve in water or in lipid-containing media. The predominantly lipophilic statins (simvastatin, fluvastatin, pitavastatin, lovastatin and atorvastatin) can easily enter cells, whereas hydrophilic statins (rosuvastatin and pravastatin) present greater hepatoselectivity. Although the beneficial role of statins in primary and secondary cardiovascular prevention has been unequivocally confirmed, the possible superiority of one statin or other regarding their solubility profile is still not well-established. In this respect, although some previously published observational studies and clinical trials observed a superiority of lipophilic statins in cardiovascular outcomes, these results could also be explained by a greater low-density lipoprotein cholesterol reduction with this statin type. On the other hand, previous studies reported conflicting results as to the possible superiority of one statin type over the other regarding heart failure outcomes. Furthermore, adverse events with statin therapy may also be related to their solubility profile. Thus, the aim of the present review was to collect clinical evidence on possible differences in cardiovascular outcomes among statins when their solubility profile is considered, and how this may also be related to the occurrence of statin-related adverse effects.

Rationale for the use of metformin and exercise to counteract statin-associated side effects

INTRODUCTION

Statins are the most widely prescribed drugs for lowering low-density lipoprotein cholesterol (LDL-C) and reducing cardiovascular morbidity and mortality. They are usually well-tolerated, but have two main safety concerns: statin-associated muscle symptoms (SAMS) and new-onset type 2 diabetes (NOD).

METHODS

A PubMed search was carried out using the following key words were used: statins, statin-associated muscle symptoms, statin myalgia, statin-associated diabetes, metformin and statins, exercise and statins.

RESULTS

Mitochondrial damage and muscle atrophy are likely the central mechanisms producing SAMS, whereas decreased glucose transport, fatty acid oxidation and insulin secretion are likely involved in the development of NOD. Metformin and exercise training share many pathways that could potentially contrast SAMS and NOD. Clinical evidence also supports the combination of statins with metformin and exercise.

CONCLUSION

This combination appears attractive both from a clinical and an economical viewpoint, since all three therapies are highly cost-effective and their combination could result in diabetes and cardiovascular disease prevention.

Improvement of Platelet Respiration by Cell-Permeable Succinate in Diabetic Patients Treated with Statins

Diabetes mellitus (DM) is the most severe metabolic disease that reached the level of a global pandemic and is associated with high cardiovascular morbidity. Statins are the first-line lipid-lowering therapy in diabetic patients with or without a history of atherosclerotic disease. Although well tolerated, chronic treatment may result in side effects that lead to treatment interruption. Mitochondrial dysfunction has emerged as a central pathomechanism in DM- and statin-induced side effects. Assessment of mitochondrial respiration in peripheral platelets has been increasingly used as a mirror of organ mitochondrial dysfunction. The present study aimed to assess the: (i) changes in mitochondrial respiration elicited by statins in patients with type 2 DM and (ii) the effects of cell-permeable succinate (NV118) on respiratory parameters in platelets harvested from these patients. No significant changes were found in global mitochondrial respiration of intact platelets isolated from diabetic patients treated with either atorvastatin or rosuvastatin. Similarly, no significant changes in mitochondrial respiration of permeabilized platelets were found between diabetic patients treated with atorvastatin and healthy controls. Acute ex vivo administration of NV118 significantly improved respiration in isolated platelets. These results prompt further research on the role of permeable succinate as a therapeutic alternative for improving mitochondrial function in metabolic pathologies and point to the role of peripheral platelets as a potential biomarker of treatment response.

Statin-Induced Myopathy: Translational Studies from Preclinical to Clinical Evidence

Statins are the most prescribed and effective drugs to treat cardiovascular diseases (CVD). Nevertheless, these drugs can be responsible for skeletal muscle toxicity which leads to reduced compliance. The discontinuation of therapy increases the incidence of CVD. Thus, it is essential to assess the risk. In fact, many studies have been performed at preclinical and clinical level to investigate pathophysiological mechanisms and clinical implications of statin myotoxicity. Consequently, new toxicological aspects and new biomarkers have arisen. Indeed, these drugs may affect gene transcription and ion transport and contribute to muscle function impairment. Identifying a marker of toxicity is important to prevent or to cure statin induced myopathy while assuring the right therapy for hypercholesterolemia and counteracting CVD. In this review we focused on the mechanisms of muscle damage discovered in preclinical and clinical studies and highlighted the pathological situations in which statin therapy should be avoided. In this context, preventive or substitutive therapies should also be evaluated.

Cell-Permeable Succinate Rescues Mitochondrial Respiration in Cellular Models of Statin Toxicity

Statins are the cornerstone of lipid-lowering therapy. Although generally well tolerated, statin-associated muscle symptoms (SAMS) represent the main reason for treatment discontinuation. Mitochondrial dysfunction of complex I has been implicated in the pathophysiology of SAMS. The present study proposed to assess the concentration-dependent ex vivo effects of three statins on mitochondrial respiration in viable human platelets and to investigate whether a cell-permeable prodrug of succinate (complex II substrate) can compensate for statin-induced mitochondrial dysfunction. Mitochondrial respiration was assessed by high-resolution respirometry in human platelets, acutely exposed to statins in the presence/absence of the prodrug NV118. Statins concentration-dependently inhibited mitochondrial respiration in both intact and permeabilized cells. Further, statins caused an increase in non-ATP generating oxygen consumption (uncoupling), severely limiting the OXPHOS coupling efficiency, a measure of the ATP generating capacity. Cerivastatin (commercially withdrawn due to muscle toxicity) displayed a similar inhibitory capacity compared with the widely prescribed and tolerable atorvastatin, but did not elicit direct complex I inhibition. NV118 increased succinate-supported mitochondrial oxygen consumption in atorvastatin/cerivastatin-exposed platelets leading to normalization of coupled (ATP generating) respiration. The results acquired in isolated human platelets were validated in a limited set of experiments using atorvastatin in HepG2 cells, reinforcing the generalizability of the findings.

The eccentric mechanotransduction, neuro-muscular transmission, and structural reversibility of muscle fatty infiltration. An experimental advanced disuse muscle-wasting model of rabbit supraspinatus

INTRODUCTION

Full-thickness rotator cuff tear is present in almost 50% of patients over age 65 years, and its degree is known to be a good predictor of the severity of muscle-wasting (MW) sarcopaenia, also known as fatty degeneration (FD). A FD CT grade > 2° is recognized as a borderline of its reversibility. A disuse model of supraspinatus FD (grade 2) in rabbits provides clinically relevant data. Therefore, the present study evaluates the correlation between eccentric mechanotransduction, neuromuscular transmission (NT), and reversibility of muscle fatty infiltration (MFI) in rabbit supraspinatus FD > 2°.

MATERIAL AND METHODS

The supraspinatus tendon was detached from the greater tubercle, infraspinatus, and subscapularis in 16 rabbits. The tendon was reinserted after 12 weeks, and the animals were euthanized 24 weeks after reconstruction. MFI was measured in the middle part of the supraspinatus. Single-fibre EMG (SFEMG) examination of the supraspinatus NT was performed on 4 animals.

RESULTS

The power of analysis was 99%. Significant differences in MFI volume were found between the operated (4.6 ±1.1%) and the opposite control sides (2.91 ±0.61%) (p < 0.001). SFEMG revealed no significant differences between the disuse and the control supraspinatus muscles (p > 0.05); however, 6.5% of the examined muscle fibres exhibited NT disorders combined with blockade of conduction in 2.5% of muscle fibres.

CONCLUSIONS

Critical MFI in a disuse model of rabbit supraspinatus FD, CT grade > 2°, is substantially reversible by eccentric training despite subclinical impairment of neuromuscular transmission. In addition, 0.63% reversal of MFI is correlated with 1% hypertrophy of type I and II muscle fibre diameter.

The insidious impact of under-diagnosed proximal weakness induced by statins

Introduction: This Perspective reassesses the consensus opinion that statin-associated muscle symptoms (SAMS) occur in <1% of users and associated myopathic proximal muscle weakness is even more rare.Areas covered: Of the over 180,000 participants in clinical trials and large registries of statin users, only a few studies have included a standard manual muscle test (MMT), dynamometry or a focused questionnaire to assess for proximal weakness and related disability in daily and recreational activities. Formal strength testing suggests, however, that weakness can be demonstrated in at least 10% of users.Expert opinion: Reporting inaccuracies about SAMS, confirmation bias among experts and physicians, absence of a standard questionnaire regarding the potential consequences of weakness on physical capacity, and the failure to routinely perform an objective assessment of strength may have led to under-diagnosis of statin-induced myopathy. A brief MMT before cholesterol-lowering agents are started and at follow-up visits, a 12-week withdrawal of the statin in the presence of new paresis without an alternative cause, and the exam finding that strength recovers off the statin are necessary to assess the incidence of drug-induced proximal weakness and inform alternative therapeutic strategies.

The Role of Structure and Biophysical Properties in the Pleiotropic Effects of Statins

Statins are a class of drugs used to lower low-density lipoprotein cholesterol and are amongst the most prescribed medications worldwide. Most statins work as a competitive inhibitor of 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGR), but statin intolerance from pleiotropic effects have been proposed to arise from non-specific binding due to poor enzyme-ligand sensitivity. Yet, research into the physicochemical properties of statins, and their interactions with off-target sites, has not progressed much over the past few decades. Here, we present a concise perspective on the role of statins in lowering serum cholesterol levels, and how their reported interactions with phospholipid membranes offer a crucial insight into the mechanism of some of the more commonly observed pleiotropic effects of statin administration. Lipophilicity, which governs hepatoselectivity, is directly related to the molecular structure of statins, which dictates interaction with and transport through membranes. The structure of statins is therefore a clinically important consideration in the treatment of hypercholesterolaemia. This review integrates the recent biophysical studies of statins with the literature on the physiological effects and provides new insights into the mechanistic cause of statin pleiotropy, and prospective means of understanding the cholesterol-independent effects of statins.

Lipid-lowering Therapies in Myositis

PURPOSE OF REVIEW

The use of lipid-lowering therapies in patients with idiopathic inflammatory myopathies (IIM) is complicated and there are no guidelines for diagnosing, monitoring, or treating atherosclerotic cardiovascular disease (ASCVD) in this group of patients.

RECENT FINDINGS

The use of lipid-lowering therapies, especially statins, is recommended in patients with increased risk for ASCVD, which includes patients with inflammatory diseases, based on recent American College of Cardiology/American Heart Association (ACC/AHA) guidelines for ASCVD management. There is accumulating evidence that patients with IIM are at increased risk for ASCVD, similar to other inflammatory diseases. Lipid-lowering therapies have side effects that may be pronounced or confounding in myositis patients, potentially limiting their use. Statins are specifically contraindicated in patients with anti 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) antibodies. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors have been shown to be safe and potentially beneficial in patients with IIM. Here, we propose a framework for (1) ASCVD risk assessment and treatment based on ACC/AHA ASCVD primary prevention guidelines; (2) myositis disease monitoring while undergoing lipid-lowering therapy; and (3) management of statin intolerance, including, indications for the use of PCSK9 inhibitors.

Genetic Variations and Frequencies of the Two Functional Single Nucleotide Polymorphisms of SLCO1B1 in the Thai Population

Aim

To investigate the variations and the frequencies of the SLCO1B1 gene in the Thai population.

Methods

Collected samples were categorized into five regions of Thailand. DNA samples were genotyped for two variants, c.388A>G and c.521T>C of the SLCO1B1, using TaqMan^® real-time PCR.

Results

The minor allele frequencies (MAFs) of two single nucleotide polymorphisms (SNPs) were not significantly different among the five regions. The most frequent haplotype was SLCO1B1*1b (frequency: 0.654), followed by *1a (frequency: 0.217), *15 (frequency: 0.128), and *5 (frequency: 0.001). We observed a similar frequency of OATP1B1 transporter phenotypes compared to other populations. 75.85% of the Thai subjects showed normal OATP1B1 activity, 22.5% showed intermediate OATP1B1 activity, and 1.58% showed low OATP1B1 activity.

Conclusion

This study reported the frequencies of the SLCO1B1 variants and the subsequent OATP1B1 activity in a large cohort of Thais that can provide important information for the guidance of personalized drug therapy.

Effect of Vitamin D Analogue on Rosuvastatin-Induced Myopathy in Wistar Rats

OBJECTIVES

Statin-induced myopathy is one of the major causes of poor adherence and discontinuation of this medication. There are contrary results regarding association of vitamin D insufficiency with statin-induced myopathy. This study was done to determine the effect of the vitamin D3 analogue alfacalcidol on Rosuvastatin-induced myopathy in rats. Methodology. Animals were divided into six groups with 6 rats in each group. Groups I and II acted as controls, Group III and Group IV were administered Rosuvastatin 120 mg/kg/day and 160 mg/kg/day, Groups V and VI were administered alfacalcidol 0.1 μg/kg/day in addition to Rosuvastatin 120 mg/kg/day and 160 mg/kg/day, respectively. All drugs were administered orally for 15 days. Plasma creatine kinase (CK) levels were estimated on day 10 and day 15. Animals were sacrificed and muscles were sent for histopathological examination.

RESULTS

On day 10, Groups V and VI showed a statistically significant increase in plasma CK levels as compared to the control (p < 0.001) and were significantly lower (p < 0.001) as compared to Groups III and IV, respectively. However, on day 15, plasma CK levels in Groups V and VI were comparable to those of control groups with a nonsignificant difference (p > 0.05). On comparing the histology, Groups V and VI showed a significant difference as compared to statin-only groups (Groups III and IV) as there were signs of regeneration, less splitting, and fragmentation of muscle fibres.

CONCLUSION

The present study shows that the vitamin D analogue alfacalcidol prevents statin-induced myopathy. The serum CK levels are comparable to the control group on day 15 of vitamin D administration.

Unripe Rubus coreanus Miquel Extract Containing Ellagic Acid Regulates AMPK, SREBP-2, HMGCR, and INSIG-1 Signaling and Cholesterol Metabolism In Vitro and In Vivo

Our previous study demonstrated that a 5% ethanol extract of unripe Rubus coreanus (5-uRCK) has hypo-cholesterolemic and anti-obesity activity. However, the molecular mechanisms of its effects are poorly characterized. We hypothesized that 5-uRCK and one of its major bioactive compounds, ellagic acid, decrease cellular and plasma cholesterol levels. Thus, we investigated the hypocholesterolemic activity and mechanism of 5-uRCK in both hepatocytes and a high-cholesterol diet (HCD)-induced rat model. Cholesterol in the liver and serum was significantly reduced by 5-uRCK and ellagic acid. The hepatic activities of HMG-CoA and CETP were reduced, and the hepatic activity of LCAT was increased by both 5-uRCK extract and ellagic acid, which also caused histological improvements. The MDA content in the aorta and serum was significantly decreased after oral administration of 5-uRCK or ellagic acid. Further immunoblotting analysis showed that AMPK phosphorylation in the liver was induced by 5-uRCK and ellagic acid, which activated AMPK, inhibiting the activity of HMGCR by inhibitory phosphorylation. In contrast, 5-uRCK and ellagic acid suppressed the nuclear translocation and activation of SREBP-2, which is a key transcription factor in cholesterol biosynthesis. In conclusion, our results suggest that 5-uRCK and its bioactive compound, ellagic acid, are useful alternative therapeutic agents to regulate blood cholesterol.

Effects of isolated or combined exposure to sibutramine and rosuvastatin on reproductive parameters of adult male rats

Many obese patients are exposed to hypolipidemic and serotonin-norepinephrine reuptake inhibitor (SNRI) drugs. Statins are one of the most marketed drugs in the world to treat dyslipidemia, while sibutramine, a SNRI drug, is prescribed in some countries to treat obesity and is detected as an additive in many adulterated weight loss supplements marketed worldwide. Previous studies reported adverse effects of isolated exposure to these drugs on male rat reproductive parameters. In the present work, we further investigated male reproductive toxicity of these drugs, administered in isolation or combination in adult rats for a longer period of treatment. Adult male rats (90 days) were treated (gavage) for 70 days with saline and dimethyl sulfoxide (control), sibutramine (10 mg/kg), rosuvastatin (5 mg/kg), or rosuvastatin combined with sibutramine. Sibutramine alone or with rosuvastatin, promoted a reduction in food intake and body weight gain, weight of the epididymis, ventral prostate and seminal vesicle; as well as decreased sperm reserves and transit time through the epididymis; androgen depletion; and increased index of cytoplasmic droplet. The rosuvastatin-treated group showed reduced frequency of ejaculation. Exposure to this drug alone or combined with sibutramine impaired epididymal morphology. Co-exposed rats had altered epididymal morphometry, and seminal vesicle and testis weights. The rats also showed decreased fertility after natural mating and a trend toward a delay in ejaculation, suggesting a small synergistic effect of these drugs. Given the greater reproductive efficiency of rodents, the results obtained in the present study raise concern regarding possible fertility impairment in men taking statins and SNRI drugs.

Assessment of bee venom therapy in animal model of statin-induced myopathy

Background

Statin-induced myopathy is the most common adverse effect of statins. Bee venom provides a potential mean of controlling immune responses and inflammatory reactions; the proposed mechanisms for statin-induced myopathy.

Objective

The present study aimed at clarification of the role of the bee venom in prevention of statin-induced myopathy.

Materials and methods

It was carried out on 30 Sprague-Dawley female rats. Rats were randomly classified into 3 groups: control group, statin group which received statins for 2 weeks, and venom group that was exposed to alternate day actual bee sting concurrent to statins administration for 2 weeks. Quantitative electromyography (QEMG) was performed as well as serum creatine kinase (CK) and cholesterol levels, in addition to in vitro muscle contractility tests.

Results

QEMG and contractility tests showed significant changes in the statin group compared to both control and venom groups. Serum cholesterol level decreased with increase in CK levels in the statin and venom groups compared to controls; however, the CK level was significantly lower in the venom group as compared to the statin group.

Conclusion

Bee venom therapy offers a simple and available means of prophylaxis against the myopathic effects induced by statins in animal model. However, it partly restricts the therapeutic effect of statins.

Muscle Toxicity of Drugs: When Drugs Turn Physiology into Pathophysiology

Drugs are prescribed to manage or prevent symptoms and diseases, but may sometimes cause unexpected toxicity to muscles. The symptomatology and clinical manifestations of the myotoxic reaction can vary significantly between drugs and between patients on the same drug. This poses a challenge on how to recognize and prevent the occurrence of drug-induced muscle toxicity. The key to appropriate management of myotoxicity is prompt recognition that symptoms of patients may be drug related and to be aware that inter-individual differences in susceptibility to drug-induced toxicity exist. The most prevalent and well-documented drug class with unintended myotoxicity are the statins, but even today new classes of drugs with unintended myotoxicity are being discovered. This review will start off by explaining the principles of drug-induced myotoxicity and the different terminologies used to distinguish between grades of toxicity. The main part of the review will focus on the most important pathogenic mechanisms by which drugs can cause muscle toxicity, which will be exemplified by drugs with high risk of muscle toxicity. This will be done by providing information on key clinical and laboratory aspects, muscle electromyography patterns and biopsy results, and pathological mechanism and management for a specific drug from each pathogenic classification. In addition, rather new classes of drugs with unintended myotoxicity will be highlighted. Furthermore, we will explain why it is so difficult to diagnose drug-induced myotoxicity, and which tests can be used as a diagnostic aid. Lastly, a brief description will be given of how to manage and treat drug-induced myotoxicity.

Statin Toxicity

There is now overwhelming evidence to support lowering LDL-c (low-density lipoprotein cholesterol) to reduce cardiovascular morbidity and mortality. Statins are a class of drugs frequently prescribed to lower cholesterol. However, in spite of their wide-spread use, discontinuation and nonadherence remains a major gap in both the primary and secondary prevention of atherosclerotic cardiovascular disease. The major reason for statin discontinuation is because of the development of statin-associated muscle symptoms, but a range of other statin-induced side effects also exist. Although the mechanisms behind these side effects have not been fully elucidated, there is an urgent need to identify those at increased risk of developing side effects as well as provide alternative treatment strategies. In this article, we review the mechanisms and clinical importance of statin toxicity and focus on the evaluation and management of statin-associated muscle symptoms.

Understanding the Patient Perception of Statin Experience: A Qualitative Study

INTRODUCTION

Statin intolerance (SI) occurs in patients with dyslipidemia treated with statins. Statin-associated symptoms have been reported, but the overall patient experience is poorly understood. No instruments are available to collect this patient experience. Our aim is to develop a patient survey to define SI from the patient's perspective, inform clinical practice, and identify potential patient characteristics and barriers associated with discontinuing treatment when statin-related difficulties are encountered.

METHODS

We conducted qualitative concept elicitation interviews with 65 patients across 12 European study sites. A semi-structured qualitative interview guide was developed based on literature review and clinician interviews. Concept elicitation interviews with patients were used to describe the patient experience and develop the conceptual framework for the survey.

RESULTS

Symptoms experienced by patients included muscle and non-muscle-related pain and discomfort; other muscle-related symptoms; gastrointestinal, cardiovascular, cold-like, fatigue-related, and sensory and systems symptoms; mood changes; and cognitive and memory problems. Impacts included limitations on general physical functioning; physical activities; social functioning; emotional impacts; sleep disturbances; decreased productivity; and increased healthcare use. Conceptual framework elements to support survey goals include demographic and clinical characteristics, health information and beliefs, statin side-effect history, symptom severity, and impact severity.

CONCLUSIONS

Symptoms and impacts described by patients showed a wider range of symptoms and impacts than usually discussed clinically. The patient survey is designed to capture information from patients who experience difficulties with statin therapy and may be useful in identifying patients who are at higher risk for giving up or discontinuing their treatment.

FUNDING

Amgen Inc.

Creatine as a Candidate to Prevent Statin Myopathy

Statins prevent cardiovascular diseases, yet their use is limited by the muscle disturbances they cause. Rarely, statin-induced myopathy is autoimmune, but more commonly it is due to direct muscle toxicity. Available evidence suggests that statin-induced creatine deficiency might be a major cause of this toxicity, and that creatine supplementation prevents it. Statins inhibit guanidinoacetate methyl transferase (GAMT), the last enzyme in the synthesis of creatine; thus, they decrease its intracellular content. Such decreased content could cause mitochondrial impairment, since creatine is the final acceptor of the phosphate group of adenosine triphosphate (ATP) at the end of mitochondrial oxidative phosphorylation. Decreased cellular synthesis of ATP would follow. Accordingly, ATP synthesis is decreased in statin-treated cells. In vitro, creatine supplementation prevents the opening of the mitochondrial permeability transition pore that is caused by statins. Clinically, creatine administration prevents statin myopathy in statin-intolerant patients. Additional research is warranted to hopefully confirm these findings. However, creatine is widely used by athletes with no adverse events, and has demonstrated to be safe even in double-blind, placebo-controlled trials of elderly individuals. Thus, it should be trialed, under medical supervision, in patients who cannot assume statin due to the occurrence of muscular symptoms.

Effects of SLCO1B1 and GATM gene variants on rosuvastatin-induced myopathy are unrelated to high plasma exposure of rosuvastatin and its metabolites

Myotoxicity is a significant factor contributing to the poor adherence and reduced effectiveness in the treatment of statins. Genetic variations and high drug plasma exposure are considered as critique causes for statin-induced myopathy (SIM). This study aims to explore the sequential influences of rosuvastatin (RST) pharmacokinetic and myopathy-related single-nucleotide polymorphisms (SNPs) on the plasma exposure to RST and its metabolites: rosuvastatin lactone (RSTL) and N-desmethyl rosuvastatin (DM-RST), and further on RST-induced myopathy. A total of 758 Chinese patients with coronary artery disease were enrolled and followed up SIM incidents for 2 years. The plasma concentrations of RST and its metabolites were determined through a validated ultra-performance liquid chromatography mass spectrometry method. Nine SNPs in six genes were genotyped by using the Sequenom MassArray iPlex platform. Results revealed that ABCG2 rs2231142 variations were highly associated with the plasma concentrations of RST, RSTL, and DM-RST (P_adj < 0.01, FDR < 0.05). CYP2C9 rs1057910 significantly affected the DM-RST concentration (P_adj < 0.01, FDR < 0.05). SLCO1B1 rs4149056 variant allele was significantly associated with high SIM risk (OR: 1.741, 95% CI: 1.180-2.568, P = 0.0052, FDR = 0.0468). Glycine amidinotransferase (GATM) rs9806699 was marginally associated with SIM incidents (OR: 0.617, 95% CI: 0.406-0.939, P = 0.0240, FDR = 0.0960). The plasma concentrations of RST and its metabolites were not significantly different between the SIM (n = 51) and control groups (n = 707) (all P > 0.05). In conclusion, SLCO1B1 and GATM genetic variants are potential biomarkers for predicting RST-induced myopathy, and their effects on SIM are unrelated to the high plasma exposure of RST and its metabolites.

Ticagrelor and Statin Interaction Induces Rhabdomyolysis and Acute Renal Failure: Case reports and Scoping Review

Ever since evidence about the increased risk of stent thrombosis with drug eluting stents (DES) surfaced in 2005, the Food and Drug Administration (FDA) has recommended the use of dual antiplatelet therapy (aspirin with P2Y12 inhibitor) following DES placement. The PLATO trial demonstrated lower mortality rates with the use of Ticagrelor when compared to clopidogrel (9.8% vs. 11.7%, p<0.001) when treating patients with acute coronary syndrome. Given their pleiotropic benefits, statins are today the second most prescribed drug in the United States and often co-prescribed with Ticagrelor. FDA's post market surveillance of Ticagrelor use along with statins in post-myocardial infarction care is now revealing novel and serious adverse events. We present two cases of rhabdomyolysis and acute renal failure (ARF) which develop while the patients were on statins and Ticagrelor. Case 1: A 66-year-old female presented with bilateral thigh pain for 3 days. One month prior to presentation, she was managed for non-ST segment elevation myocardial infarction (NSTEMI) and had been started on aspirin, ticagrelor and simvastatin. Laboratory values revealed creatinine kinase (CK) level at 40,000 U/L and creatinine 3.2 mg/dL suggesting rhabdomyolysis and ARF. Case 2: A 63-year-old male presented with generalized body aches and fatigue for 4 days. He had sustained STEMI two months before and received two drug eluting stents (DES) and aspirin, ticagrelor and rosuvastatin had been initiated. CK was 380,000 U/L and creatinine 7.94 mg/dL suggesting rhabdomyolysis and ARF. Both patients presented with rhabdomyolysis and acute renal failure within weeks after ticagrelor and statin were commenced. A review of the literature indicated that 11 similar cases of ticagrelor-induced ARF and rhabdomyolysis had been reported. Ticagrelor competes with statins when metabolized by cytochrome P450 (CYP) 3A4 leading to statin retention, leading to major adverse effects like rhabdomyolysis and acute renal failure. Our review is intended to alert clinicians about this important drug interaction.

Plasma 2-hydroxyglutarate, a promising prognostic biomarker candidate for skeletal muscle injury in Fischer 344 rats

Previously, we have demonstrated the potential of plasma 2-hydroxyglutarate (2HG) as an easily detectable biomarker for skeletal muscle injury in rats. Here, we examined whether plasma 2HG was superior to conventional skeletal muscle damage biomarkers, including aspartate aminotransferase (AST), creatine kinase (CK), and skeletal muscle-type CK isoenzyme (CK-MM) levels, in rats. Skeletal muscle injury was induced in 4- or 9-week-old male Fischer 344 rats by cerivastatin (CER) or tetramethyl-p-phenylenediamine (TMPD) administration. Plasma 2HG levels were measured on days 4, 8, and 11 (CER group) and at 6 and 24 hr post-administration (TMPD group). Plasma AST, CK, and CK-MM activities and histopathological changes in the rectus femoris muscle were evaluated at the study endpoints. In the CER group, AST, CK, and CK-MM increased in 4- and 9-week-old rats, whereas increases in CK (4- and 9-week-old rats) and CK-MM (4-week-old rats) were not obvious in the TMPD group. In both 4- and 9-week-old rats, plasma 2HG increased on day 8 and at 24 hr post-administration in the CER and TMPD groups, respectively. Histopathological analysis revealed myofiber vacuolation and necrosis in both groups. The histopathological damage to the rectus femoris muscle was more severe in the CER than in the TMPD group. Increased plasma 2HG was associated with CER- and TMPD-induced skeletal muscle injuries in rats and was not affected by age differences or repeated blood collection. The results suggest that plasma 2HG is superior to CK and CK-MM as a biomarker for mild skeletal muscle injury.

The Role of Nutraceuticals in Statin Intolerant Patients

Statins are the most common drugs administered for patients with cardiovascular disease. However, due to statin-associated muscle symptoms, adherence to statin therapy is challenging in clinical practice. Certain nutraceuticals, such as red yeast rice, bergamot, berberine, artichoke, soluble fiber, and plant sterols and stanols alone or in combination with each other, as well as with ezetimibe, might be considered as an alternative or add-on therapy to statins, although there is still insufficient evidence available with respect to long-term safety and effectiveness on cardiovascular disease prevention and treatment. These nutraceuticals could exert significant lipid-lowering activity and might present multiple non-lipid-lowering actions, including improvement of endothelial dysfunction and arterial stiffness, as well as anti-inflammatory and antioxidative properties. The aim of this expert opinion paper is to provide the first attempt at recommendation on the management of statin intolerance through the use of nutraceuticals with particular attention on those with effective low-density lipoprotein cholesterol reduction.

Creatine supplementation does not alter the creatine kinase response to eccentric exercise in healthy adults on atorvastatin

BACKGROUND

Serum creatine kinase (CK) levels are higher after eccentric, muscle-damaging exercise in statin-treated patients. This could contribute to the increased statin-associated muscle symptoms reported in physically active individuals.

OBJECTIVE

We tested the hypothesis in this pilot study that creatine (Cr) monohydrate supplementation would reduce the CK response to eccentric exercise in patients using statins to determine if Cr supplementation could be a strategy to mitigate statin-associated muscle symptoms in physically active individuals.

METHODS

Healthy, nonsmoking men (n = 5) and women (n = 14) were randomized to Cr monohydrate = atorvastatin 80 mg + 10 g Cr monohydrate (n = 10, age = 60 ± 7 years) or to placebo (PL) = atorvastatin 80 mg + PL (n = 9, age = 52 ± 6 years). After 4 weeks of treatment, subjects performed 45 minutes of eccentric exercise (downhill walking at a -15% grade). Serum CK levels, muscle soreness (visual analog scale after two squats), and muscle pain severity and interference (using the brief pain inventory) were measured before and after 4 weeks of treatment, and then for 4 consecutive days after downhill walking. Vitamin D, or serum 25(OH)D, was also measured at baseline.

RESULTS

The PL group was younger (P = .01) but not otherwise different in blood lipids, vitamin D, CK, muscle visual analog scale, and pain scores before (all P > .21) or after (all P > .12) treatment. CK increased in all subjects after downhill walking (P < .01), but neither the relative peak change (expressed as group mean difference with 95% confidence intervals: 43.52% [-196.41, 283.45]) nor the absolute peak change (67.38 U/L [-121.55, 256.31]) relative to baseline was different between groups (P = .46 and .71, respectively). A similar lack of treatment effect was observed for muscle soreness (11.03 mm [-9.49, 31.55]), pain severity (0.77 pts [-0.95, 2.50]), and pain interference (1.02 pts [-1.25, 3.29]) with P-values for group comparisons = 0.27, 0.36, and 0.35, respectively. However, subjects with "insufficient" Vitamin D < 30 ng/mL (n = 10) had an ∼2-fold greater CK increase with eccentric exercise (nominal P-value = .04) than subjects with higher vitamin D levels.

CONCLUSION

Cr monohydrate did not reduce CK increases after exercise in statin-treated subjects. We did observe that low vitamin D levels are associated with a greater CK response to eccentric exercise in statin-treated subjects.

Management of Statin Intolerance in 2018: Still More Questions Than Answers

Statin therapy is generally well tolerated and very effective in the prevention and treatment of cardiovascular disease, regardless of cholesterol levels; however, it can be associated with various adverse events (myalgia, myopathy, rhabdomyolysis, and diabetes mellitus, among others). Patients frequently discontinue statin therapy without medical advice because of perceived side effects and consequently increase their risk for cardiovascular events. In patients with statin intolerance, it may be advisable to change the dose, switch to a different statin, or try an alternate-day regimen. If intolerance is associated with all statins-even at the lowest dose-non-statin drugs and certain nutraceuticals can be considered. This review focuses on the definition of statin intolerance and on the development of clinical and therapeutic strategies for its management, including emerging alternative therapies.