The cardioprotective effects of statins

Burning Mouth Syndrome From Statin Use: A Case Study

Statins are one of the most commonly prescribed medications in America. They are known for their ability to decrease cholesterol. Although generally well-tolerated, they are known to cause a variety of moderate side effects. Herein, we report on a rarely reported side effect of statin-induced neuropathy. A 35-year-old male with type IV hyperlipoproteinemia presented to the neurology outpatient clinic with complaints of tongue burning after taking a statin for just seven days. After being placed on Atorvastatin 20 mg daily, he developed dysesthesias in his tongue and mouth. No other prescribed or over-the-counter medications were being taken at the time. A detailed neurological examination was conducted and was found to be normal, besides dysesthesias of the tongue. Atorvastatin was discontinued, and the burning resolved within three weeks. Burning mouth syndrome (BMS) is a disorder that causes painful dysesthesias of the tongue thought to be caused by small fiber neuropathy. Small fiber neuropathy affects sensory and autonomic small fibers, resulting in both sensory and autonomic symptoms. Sensory symptoms can include burning, tingling, and stabbing discomfort. Though there are many causes of small fiber neuropathy, this case is rare in the fact that it only involves the patient's tongue.

Aerobic exercise alleviates statin-induced PCSK9 upregulation by increasing epoxyeicosatrienoic acid levels through the FoxO3a-Sirt6 axis

BACKGROUND

Statins are the cornerstone of low-density lipoprotein cholesterol (LDL-C)-lowering therapy; however, the therapeutic efficacy of statins in countering atherosclerotic cardiovascular disease (ASCVD) is compromised by the concurrent elevation of proprotein convertase subtilisin/kexin type 9 (PCSK9), a pivotal molecule that increases LDL-C levels. Aerobic exercise lowers PCSK9 levels, but the underlying mechanism remains unclear. Therefore, we investigated how aerobic exercise can ameliorate statin-induced increases in PCSK9 levels.

METHODS

Three-week-old male American Institute of Cancer Research (ICR) mice were fed a high-fat-cholesterol diet (HFD) for 12 weeks and then administered atorvastatin alone or atorvastatin combined with aerobic exercise (Statin + Ex). Moreover, a total of 165 participants with stable coronary heart disease (CHD) enrolled at the Inpatient and Outpatient Departments of the Second Xiangya Hospital of Central South University, China, from January 2018 to July 2020 were randomized into the Statin group (male/female = 51/33) and Statin + Ex group (male/female = 52/29). Patients in the Statin + Ex group underwent treadmill exercise of 45-60 min/day for 7 days.

RESULTS

Aerobic exercise effectively alleviated statin-induced PCSK9 upregulation in human patients with CHD and hypercholesterolemic ICR mice (all p < 0.05). Mechanistically, our findings revealed that aerobic exercise induced elevated epoxyeicosatrienoic acids (EETs) plasma levels while concurrently reducing the activity of soluble epoxide hydrolase (sEH) (all p < 0.05), an enzyme responsible for EETs degradation. Further, EETs significantly suppressed PCSK9 expression, subsequently reducing the LDL-C levels (all p < 0.05); this effect was mediated via the activation of the forkhead box O3a-silent mating type information regulation 2 homolog 6 (FoxO3a-Sirt6) axis, with no impact on the sterol regulatory element binding protein 2 and 3-hydroxy-3-methylglutaryl-CoA reductase (SREBP2-HMGCR) pathway.

CONCLUSION

Our study sheds light on the paradigm of "Exercise is Medicine", providing evidence to support the use of statins combined with exercise in reducing LDL-C levels, and unveils potential avenues for clinical applications of sEH inhibitors, presenting novel prospects for therapeutic interventions in ASCVD.

Evaluation of rosuvastatin-induced QT prolongation risk using real-world data, in vitro cardiomyocyte studies, and mortality assessment

Drug-induced QT prolongation is attributed to several mechanisms, including hERG channel blockage. However, the risks, mechanisms, and the effects of rosuvastatin-induced QT prolongation remain unclear. Therefore, this study assessed the risk of rosuvastatin-induced QT prolongation using (1) real-world data with two different settings, namely case-control and retrospective cohort study designs; (2) laboratory experiments using human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM); (3) nationwide claim data for mortality risk evaluation. Real-world data showed an association between QT prolongation and the use of rosuvastatin (OR [95% CI], 1.30 [1.21-1.39]) but not for atorvastatin (OR [95% CI], 0.98 [0.89-1.07]). Rosuvastatin also affected the sodium and calcium channel activities of cardiomyocytes in vitro. However, rosuvastatin exposure was not associated with a high risk of all-cause mortality (HR [95% CI], 0.95 [0.89-1.01]). Overall, these results suggest that rosuvastatin use increased the risk of QT prolongation in real-world settings, significantly affecting the action potential of hiPSC-CMs in laboratory settings. Long-term rosuvastatin treatment was not associated with mortality. In conclusion, while our study links rosuvastatin use to potential QT prolongation and possible influence on the action potential of hiPSC-CMs, long-term use does not show increased mortality, necessitating further research for conclusive real-world applications.

The Multifaceted Biology of PCSK9

This article reviews the discovery of PCSK9, its structure-function characteristics, and its presently known and proposed novel biological functions. The major critical function of PCSK9 deduced from human and mouse studies, as well as cellular and structural analyses, is its role in increasing the levels of circulating low-density lipoprotein (LDL)-cholesterol (LDLc), via its ability to enhance the sorting and escort of the cell surface LDL receptor (LDLR) to lysosomes. This implicates the binding of the catalytic domain of PCSK9 to the EGF-A domain of the LDLR. This also requires the presence of the C-terminal Cys/His-rich domain, its binding to the secreted cytosolic cyclase associated protein 1, and possibly another membrane-bound "protein X". Curiously, in PCSK9-deficient mice, an alternative to the downregulation of the surface levels of the LDLR by PCSK9 is taking place in the liver of female mice in a 17β-estradiol-dependent manner by still an unknown mechanism. Recent studies have extended our understanding of the biological functions of PCSK9, namely its implication in septic shock, vascular inflammation, viral infections (Dengue; SARS-CoV-2) or immune checkpoint modulation in cancer via the regulation of the cell surface levels of the T-cell receptor and MHC-I, which govern the antitumoral activity of CD8+ T cells. Because PCSK9 inhibition may be advantageous in these processes, the availability of injectable safe PCSK9 inhibitors that reduces by 50% to 60% LDLc above the effect of statins is highly valuable. Indeed, injectable PCSK9 monoclonal antibody or small interfering RNA could be added to current immunotherapies in cancer/metastasis.

Muscle and cardiac therapeutic strategies for Duchenne muscular dystrophy: past, present, and future

BACKGROUND

Duchenne muscular dystrophy (DMD) is a severe X-linked neuromuscular childhood disorder that causes progressive muscle weakness and degeneration and results in functional decline, loss of ambulation and early death of young men due to cardiac or respiratory failure. Although the major cause of the disease has been known for many years-namely mutation in the DMD gene encoding dystrophin, one of the largest human genes-DMD is still incurable, and its treatment is challenging.

METHODS

A comprehensive and systematic review of literature on the gene, cell, and pharmacological experimental therapies aimed at restoring functional dystrophin or to counteract the associated processes contributing to disease progression like inflammation, fibrosis, calcium signaling or angiogenesis was carried out.

RESULTS

Although some therapies lead to satisfying effects in skeletal muscle, they are highly ineffective in the heart; therefore, targeting defective cardiac and respiratory systems is vital in DMD patients. Unfortunately, most of the pharmacological compounds treat only the symptoms of the disease. Some drugs addressing the underlying cause, like eteplirsen, golodirsen, and ataluren, have recently been conditionally approved; however, they can correct only specific mutations in the DMD gene and are therefore suitable for small sub-populations of affected individuals.

CONCLUSION

In this review, we summarize the possible therapeutic options and describe the current status of various, still imperfect, strategies used for attenuating the disease progression.

PCSK9 inhibitors in the current management of atherosclerosis

The history of proprotein convertase subtilisin/kexin type 9 (PCSK9) in medical science is fascinating and the evolution of knowledge of its function has resulted in new medications of major importance for the cardiovascular (CV) patient. PCSK9 functions as a negative control or feedback for the cell surface receptors for low-density lipoprotein including its component of cholesterol (LDL-C). The initial and key findings were that different abnormalities of PCSK9 can result in an increase or a decrease of LDL-C because of more or less suppression of cell surface receptors. These observations gave hints and awoke interest that it might be possible to prepare monoclonal antibodies to PCSK9 and decrease its activity, after which there should be more active LDL-C cell receptors. The rest is a fascinating story that currently has resulted in two PCSK9 inhibitors, alirocumab and evolocumab, which, on average, decrease LDL-C approximately 50%. Nevertheless, if there are no contraindications, statins remain the standard of prevention for the high-risk CV patient and this includes both secondary and primary prevention. The new inhibitors are for the patient that does not attain the desired target for LDL-C reduction while taking a maximum statin dose or who does not tolerate any statin dose whatsoever. Atherosclerosis can be considered a metabolic disease and the clinician needs to realize this and think more and more of CV prevention. These inhibitors can contribute to both the stabilization and regression of atherosclerotic plaques and thereby avoid or delay major adverse cardiac events. (United States).

Is There an Ideal Low-Density Lipoprotein Cholesterol Level? Confusion regarding Lipid Guidelines, Low-Density Lipoprotein Cholesterol Targets, and Medical Management

There are multiple guidelines for managing patients with high-risk cardiovascular disease, and unfortunately for the practicing clinician, these guidelines are quite variable. Some are fairly specific whereas others are not, resulting in a great deal of confusion regarding whether management of low-density lipoprotein cholesterol (LDL-C) should be tailored only, targeted only, or managed by a combination of both. In the management of cardiovascular disease, favorable cardiovascular outcomes can be obtained by simply lowering the LDL-C in the absence of any other medications. The advent of statins, the most potent LDL-C-lowering medication yet when developed, provided benefits augmented by the presence of multiple pleiotropic effects. Tailoring and/or targeting the decrease in LDL-C is also an issue of concern. Then, in 2016, the new proprotein convertase sutilisin-like/kexin type 9 (PCSK9) inhibitors appeared, providing a solution to patients with high-risk cardiovascular disease with statin intolerance and those who did not attain a desired LDL-C level while on a high-dose statin. These new PCSK9 inhibitors necessitate a determination of how low the LDL-C can and should go, most likely safely down to a beneficial level of 25 mg/dL for the highest-risk patient. These issues are documented and discussed with an attempt to help the reader make an informed risk management decision.

Simvastatin increases AQP2 urinary excretion in hypercholesterolemic patients: A pleiotropic effect of interest for patients with impaired AQP2 trafficking

We previously reported that statins improve the symptoms of X-linked nephrogenic diabetes insipidus (X-NDI) in animal models. The aim of this study was to verify whether the pleiotropic effect of statins on AQP2 trafficking and kidney-concentrating ability, observed in rodents, was attainable in humans at therapeutic doses. We enrolled 24 naïve hypercholesterolemic patients and measured urine excretion of AQP2 (uAQP2) at baseline and during 12 weeks of treatment with simvastatin 20 mg/day. Simvastatin induced a rapid and significant increase of uAQP2, reduced the 24-hour diuresis, and increased urine osmolality. These effects were also maintained in patients chronically treated with statins for at least 1 year. This study strongly suggests that statins may effectively enhance the efficacy of current pharmacological treatment of patients with urine-concentrating defects caused by defective AQP2 plasma membrane trafficking, like X-NDI.

Diabetes to cardiovascular disease: is depression the potential missing link?

The etiopathological consequences of diabetes and its imperative sequels have been explored extensively in the scientific arena of cardiovascular diabetology. Innumerable risk covariates and confounders have been delineated for the primary and secondary prevention of diabetes and cardiovascular diseases (CVD). However, an intricate interaction of depression on them has been largely overlooked. Depression influences and participates in each and every step that worsens the diabetic state for developing cardiovascular complications. The dilemma is that it coexists, remains silent and generally not considered as relevant clinical parameter amenable to intervention. In this review, it is highlighted that depression has strong association and linkages with both diabetes and CVD and it should be considered and diagnosed at every stage of the diabetes to CVD continuum. Careful attention to the diagnosis and management of these disease states would contribute in lessening the CVD burden of the society.

A novel therapeutic effect of statins on nephrogenic diabetes insipidus

Statins competitively inhibit hepatic 3-hydroxy-3-methylglutaryl-coenzyme A reductase, resulting in reduced plasma total and low-density lipoprotein cholesterol levels. Recently, it has been shown that statins exert additional ‘pleiotropic’ effects by increasing expression levels of the membrane water channels aquaporin 2 (AQP2). AQP2 is localized mainly in the kidney and plays a critical role in determining cellular water content. This additional effect is independent of cholesterol homoeostasis, and depends on depletion of mevalonate-derived intermediates of sterol synthetic pathways, i.e. farnesylpyrophosphate and geranylgeranylpyrophosphate. By up-regulating the expression levels of AQP2, statins increase water reabsorption by the kidney, thus opening up a new avenue in treating patients with nephrogenic diabetes insipidus (NDI), a hereditary disease that yet lacks high-powered and limited side effects therapy. Aspects related to water balance determined by AQP2 in the kidney, as well as standard and novel therapeutic strategies of NDI are discussed.

Coronary atherosclerosis, low-density lipoproteins and markers of thrombosis, inflammation and endothelial dysfunction

Available information regarding the relation among atherosclerosis, low-density lipoproteins, markers of thrombosis, inflammation and endothelial dysfunction has accumulated, but is still very limited, making only minimal contributions to clinical decision-making. Many more clinical trials are needed, but unless there is a relationship between atherosclerosis prevention, specific markers and a pharmaceutical product, financial support for such trials will be difficult to obtain. The anti-inflammatory effect of statins is well established. Angiotensin-converting enzyme inhibitors are generally not thought of as having anti-inflammatory effects, but the European Trial on Reduction of Cardiac Events with Perindopril in Stable Coronary Artery Disease (EUROPA) study observed extensive RR reduction with perindopril. It was explained not simply by control of hypertension, but by reduced activity of multiple factors, supported by specific substudies. The 'cardiovascular continuum' is an excellent unifying term to explain atherosclerosis mechanisms, relate mechanisms to clinical understanding, and assist the clinician in selecting the appropriate prevention and control therapies. This so-called continuum actually describes a relationship among different biochemical, enzymatic and hormonal factors that affect the cardiovascular system. It can be seen in the downregulation of the angiotensin II receptor type 1 by statins, which contributes to hypertension control while lowering low-density lipoproteins. Peroxisome proliferator activator receptor-gamma also demonstrates the cardiovascular continuum with activation of the receptor by glitazones. The glitazones increase insulin sensitivity for diabetes control. Activation of the peroxisome proliferator activator receptor-gamma inhibits inflammation, which is possibly related to atherosclerosis, normalization of endothelial function, suppression of metalloproteinases and a decrease in smooth muscle cell migration. All of these effects may decrease atherosclerosis production while improving control of diabetes mellitus, a key disease in the cardiovascular continuum for development of atherosclerosis. Consideration of such interrelationships is just scratching the surface. Nevertheless, it can be seen that the complicated process of atherosclerosis development has a multifaceted explanation that has been minimally defined, but holds the key to prevention and control of this major medical problem faced in modern society.

Pitavastatin suppresses mitogen activated protein kinase-mediated Erg-1 induction in human vascular smooth muscle cells

Statins have been demonstrated to elicit a broad range of cellular events resulting in an attenuation of the inflammatory response and enhanced protection to the components of the vessel wall. The present study was designed to examine the effect of pitavastatin on pathways associated with the proinflammatory gene, early growth response (Egr)-1, in human vascular smooth muscle cells. Pretreatment with pitavastatin resulted in a dose-dependent reduction in Egr-1 protein and suppressed Egr-1 mRNA expression in response to phorbol 12-myristate 13-acetate (PMA). A reduction in Egr-1 expression reduced the activation of NGFI-A binding protein (NAB)-2, an Egr-1-dependent gene. Furthermore, these events appeared to be dependent on the ability of pitavastatin to attenuate signaling cascades associated with extracellular regulated kinase (ERK) 1/2, but not p38 and c-Jun N-terminal kinase (JNK).

Ongoing clinical trials of the pleiotropic effects of statins

BACKGROUND

The multiple effects (ie, pleiotropic effects of statins) have received increasing recognition and may have clinical applicability across a broad range of cardiovascular and noncardiovascular conditions.

OBJECTIVE

To determine the relevance and significance of ongoing clinical trials of the pleiotropic effects of statins, focusing on nonlipid effects.

METHOD

Ongoing trials were identified through personal communication, reports presented at scientific meetings (2000-2004), and queries made to AstraZeneca, Bristol-Myers Squibb Co, Merck & Co, Novartis, and Pfizer, manufacturers of the currently marketed statins. Published trials and other source material were identified through electronic searches on MEDLINE (1990-2003), abstract books, and references identified from bibliographies of pertinent articles. Eligible studies were the clinical trials of statins currently under way in which primary or secondary outcomes included the statins' nonlipid (ie, pleiotropic) effect(s). Data were extracted and trial quality was assessed by the authors.

RESULTS

Of the 22 ongoing trials of the nonlipid effects of statins identified, 10 assessed inflammatory markers and plaque stabilization, 4 assessed oxidized low density lipoprotein/vascular oxidant stress, 3 assessed end-stage renal disease, 3 assessed fibrinogen/viscosity, 2 assessed endothelial function, 2 assessed acute coronary syndrome, 2 assessed aortic stenosis progression, and 1 each assessed hypertension, osteoporosis, ischemic burden, Alzheimer's disease, multiple sclerosis, and stroke (outcomes often overlapped).

CONCLUSION

Given the excellent safety and tolerability of statins as a class, full exploration of their pleiotropic effects has the potential to provide additional benefits to many patients.

Inflammatory, atherothrombotic aspects of type 2 diabetes

BACKGROUND

There is a tight association between diabetes and cardiovascular disease - both occur more commonly together than independently. The development of vascular disease is dependent upon complex interactions between a number of metabolic pathways involving both fluid phase proteins and cellular components. Inflammation and coagulation are two intimately linked processes that are co-regulated. The characteristic cluster of risk factors - hypertension, hyperinsulinaemia, hyperglycaemia and lipid abnormalities, which are associated with insulin resistance - have been expanded to include inflammation and thrombotic risk. Studies in patients with diabetes indicate a higher prevalence of both inflammatory cells and thrombosis in coronary plaques in comparison to non-diabetic subjects and measures of C-reactive protein predict the development of both diabetes and cardio vascular disease in prospective studies.

SCOPE

This review (based on MEDLINE searches, 1990 to 2005) looks at the inflammatory, atherothrombotic aspects of type 2 diabetes that may be involved in the accelerated development of vascular disease in the population with diabetes.

Management of atherogenic dyslipidemia of the metabolic syndrome: evolving rationale for combined drug therapy

Atherogenic dyslipidemia is prevalent in various conditions associated with central obesity, hypertension, hyperurecemia, and impaired beta-cell function (ie, the metabolic syndrome). Because of clinical trial evidence, most high-risk patients with atherogenic dyslipidemia require statin therapy. Coadministration of drugs targeted to reduction of low-density lipoprotein precursors, however,is likely to improve the metabolic profile of all non-high-density lipoproteins and produce a significant rise in high-density lipoprotein cholesterol. Large-scale clinical trials with combined drug therapy that show coronary heart disease (CHD) risk reduction or improvement in CHD are needed. It is also possible that new drugs are needed to target fatty acid metabolism and inflammation. As understanding of the metabolic origins of atherogenic dyslipidemia increases, it is possible that new targets of therapy will be identified and that new drug combinations will prove to be even more efficacious than those currently available for treatment of this condition.

Statins upregulate PCSK9, the gene encoding the proprotein convertase neural apoptosis-regulated convertase-1 implicated in familial hypercholesterolemia

OBJECTIVE

Neural apoptosis-regulated convertase (NARC)-1 is the newest member of the proprotein convertase family implicated in the cleavage of a variety of protein precursors. The NARC-1 gene, PCSK9, has been identified recently as the third locus implicated in autosomal dominant hypercholesterolemia (ADH). The 2 other known genes implicated in ADH encode the low-density lipoprotein receptor and apolipoprotein B. As an approach toward the elucidation of the physiological role(s) of NARC-1, we studied its transcriptional regulation.

METHODS AND RESULTS

Using quantitative RT-PCR, we assessed NARC-1 regulation under conditions known to regulate genes involved in cholesterol metabolism in HepG2 cells and in human primary hepatocytes. We found that NARC-1 expression was strongly induced by statins in a dose-dependent manner and that this induction was efficiently reversed by mevalonate. NARC-1 mRNA level was increased by cholesterol depletion but insensitive to liver X receptor activation. Human, mouse, and rat PCSK9 promoters contain 2 typical conserved motifs for cholesterol regulation: a sterol regulatory element (SRE) and an Sp1 site.

CONCLUSIONS

PCSK9 regulation is typical of that of the genes implicated in lipoprotein metabolism. In vivo, PCSK9 is probably a target of SRE-binding protein (SREBP)-2.