The effect of donepezil treatment on cardiovascular mortality

Drug repurposing: A multi targetted approach to treat cardiac disease from existing classical drugs to modern drug discovery

Cardiovascular diseases (CVDs) are characterized by abnormalities in the heart, blood vessels, and blood flow. CVDs comprise a diverse set of health issues. There are several types of CVDs like stroke, endothelial dysfunction, thrombosis, atherosclerosis, plaque instability and heart failure. Identification of a new drug for heart disease takes longer duration and its safety efficacy test takes even longer duration of research and approval. This chapter explores drug repurposing, nano-therapy, and plant-based treatments for managing CVDs from existing drugs which saves time and safety issues with testing new drugs. Existing drugs like statins, ACE inhibitor, warfarin, beta blockers, aspirin and metformin have been found to be useful in treating cardiac disease. For better drug delivery, nano therapy is opening new avenues for cardiac research by targeting interleukin (IL), TNF and other proteins by proteome interactome analysis. Nanoparticles enable precise delivery to atherosclerotic plaques, inflammation areas, and damaged cardiac tissues. Advancements in nano therapeutic agents, such as drug-eluting stents and drug-loaded nanoparticles are transforming CVDs management. Plant-based treatments, containing phytochemicals from Botanical sources, have potential cardiovascular benefits. These phytochemicals can mitigate risk factors associated with CVDs. The integration of these strategies opens new avenues for personalized, effective, and minimally invasive cardiovascular care. Altogether, traditional drugs, phytochemicals along with nanoparticles can revolutionize the future cardiac health care by identifying their signaling pathway, mechanism and interactome analysis.

Effect of donepezil hydrochloride on the transgenic Drosophila expressing human Aβ-42

CONCLUSION

The results suggest that donepezil hydrochloride is potent enough to reduce the AD symptoms being mimicked in transgenic flies.

Effects of metformin and donepezil on the prevention of doxorubicin-induced cardiotoxicity in breast cancer: a randomized controlled trial

Doxorubicin (DOX) causes deleterious cardiotoxicity. We aimed to investigate the protective roles of metformin and donepezil against DOX-induced cardiotoxicity. In this randomized-controlled trial, 143 female breast cancer patients were enrolled. Metformin (n = 43), donepezil (n = 52), or placebo (n = 48) were prescribed during DOX treatment. The primary endpoint was a proportion of patients with high sensitivity troponin-I (hsTnI) more than the 99th percentile value (> 15.6 ng/L) after DOX treatment. The secondary outcomes were the changes in the hsTnI, N-terminal pro-B-type natriuretic peptide (NT-proBNP), left ventricular ejection fraction (LVEF), global longitudinal strain (GLS) and peripheral blood mononuclear cells analysis for mitochondrial respiration. Baseline characteristics were similar between the groups. The primary endpoint occurred in 58.54% of metformin group, 76.92% in donepezil group, and 69.77% in placebo group (p = 0.215). The level of hsTnI increased after receiving DOX with subsequent decline in LVEF and GLS. Metformin and donepezil did not attenuate hsTnI elevation, LVEF or GLS reduction. There was no significant change in NT-proBNP level. Mitochondrial respiratory dysfunction was observed in the placebo and donepezil groups. However, metformin preserved mitochondrial respiration during DOX therapy. In conclusion, co-treatment with metformin or donepezil did not prevent myocardial injury. Metformin had a favorable mitochondrial outcome and warranted future studies.

Targeting Sigma Receptors for the Treatment of Neurodegenerative and Neurodevelopmental Disorders

The sigma-1 receptor is a 223 amino acid-long protein with a recently identified structure. The sigma-2 receptor is a genetically unrelated protein with a similarly shaped binding pocket and acts to influence cellular activities similar to the sigma-1 receptor. Both proteins are highly expressed in neuronal tissues. As such, they have become targets for treating neurological diseases, including Alzheimer's disease (AD), Huntington's disease (HD), Parkinson's disease (PD), multiple sclerosis (MS), Rett syndrome (RS), developmental and epileptic encephalopathies (DEE), and motor neuron disease/amyotrophic lateral sclerosis (MND/ALS). In recent years, there have been many pre-clinical and clinical studies of sigma receptor (1 and 2) ligands for treating neurological disease. Drugs such as blarcamesine, dextromethorphan and pridopidine, which have sigma-1 receptor activity as part of their pharmacological profile, are effective in treating multiple aspects of several neurological diseases. Furthermore, several sigma-2 receptor ligands are under investigation, including CT1812, rivastigmine and SAS0132. This review aims to provide a current and up-to-date analysis of the current clinical and pre-clinical data of drugs with sigma receptor activities for treating neurological disease.

Repurposing of Drugs for Cardiometabolic Disorders: An Out and Out Cumulation

Cardiometabolic disorders (CMD) is a constellation of metabolic predisposing factors for atherosclerosis such as insulin resistance (IR) or diabetes mellitus (DM), systemic hypertension, central obesity, and dyslipidemia. Cardiometabolic diseases (CMDs) continue to be the leading cause of mortality in both developed and developing nations, accounting for over 32% of all fatalities globally each year. Furthermore, dyslipidemia, angina, arrhythmia, heart failure, myocardial infarction (MI), and diabetes mellitus are the major causes of death, accounting for an estimated 19 million deaths in 2012. CVDs will kill more than 23 million individuals each year by 2030. Nonetheless, new drug development (NDD) in CMDs has been increasingly difficult in recent decades due to increased costs and a lower success rate. Drug repositioning in CMDs looks promising in this scenario for launching current medicines for new therapeutic indications. Repositioning is an ancient method that dates back to the 1960s and is mostly based on coincidental findings during medication trials. One significant advantage of repositioning is that the drug's safety profile is well known, lowering the odds of failure owing to undesirable toxic effects. Furthermore, repositioning takes less time and money than NDD. Given these facts, pharmaceutical corporations are becoming more interested in medication repositioning. In this follow-up, we discussed the notion of repositioning and provided some examples of repositioned medications in cardiometabolic disorders.

Donepezil-associated survival benefits among Alzheimer's disease patients are retained but not enhanced during COVID-19 infections

Background and Aim

Donepezil is a front-line treatment for Alzheimer's disease. Donepezil treatment is associated with decreased risk of all-cause mortality. Specific protection is observed in pneumonia and cardiovascular disease. We hypothesized that donepezil treatment would improve mortality among Alzheimer's patients following infection with COVID-19. The objective of this study is to assess the influence of ongoing donepezil treatment on survival in Alzheimer's disease patients after polymerase chain reaction (PCR)-confirmed COVID-19 infection.

Methods

This is a retrospective cohort study. We conducted a national survey of Veterans with Alzheimer's disease to assess the influence of ongoing donepezil treatment on survival in Alzheimer's disease patients after PCR-confirmed COVID-19 infection. We assessed all-cause 30-day mortality stratified by COVID-19 infection and donepezil use, estimating odds ratios using multivariate logistic regression.

Results

Among people with Alzheimer's disease and COVID-19, all-cause 30-day mortality was 29% (47/163) for people taking donepezil compared with 38% (159/419) for those who were not. Among people with Alzheimer's disease without COVID-19, all-cause 30-day mortality was 5% (189/4189) for people taking donepezil compared with 7% (712/10,241) for those who were not. Adjusting for covariates, the decrease in mortality associated with donepezil did not differ between people with and without COVID-19 (interaction p = 0.710).

Conclusion

The known survival benefits of donepezil were retained but not found to be specific to COVID-19 among people with Alzheimer's disease.

Repurposing drugs to treat cardiovascular disease in the era of precision medicine

Drug repurposing is the use of a given therapeutic agent for indications other than that for which it was originally designed or intended. The concept is appealing because of potentially lower development costs and shorter timelines than are needed to produce a new drug. To date, drug repurposing for cardiovascular indications has been opportunistic and driven by knowledge of disease mechanisms or serendipitous observation rather than by systematic endeavours to match an existing drug to a new indication. Innovations in two areas of personalized medicine — computational approaches to associate drug effects with disease signatures and predictive model systems to screen drugs for disease-modifying activities — support efforts that together create an efficient pipeline to systematically repurpose drugs to treat cardiovascular disease. Furthermore, new experimental strategies that guide the medicinal chemistry re-engineering of drugs could improve repurposing efforts by tailoring a medicine to its new indication. In this Review, we summarize the historical approach to repurposing and discuss the technological advances that have created a new landscape of opportunities.

Drugs can be repurposed for new therapeutic indications. In this Review, Mercola and colleagues summarize the latest techniques for systematic drug repurposing and re-engineering, which could increase the pace, efficiency and cost-effectiveness of drug discovery for the treatment of cardiovascular disease.

Contemporary technologies are expected to make drug repurposing large-scale, systematic and deliberate rather than opportunistic.

New experimental and computational tools harness patient genomics for drug repurposing.

Discovery of repurposed drugs on the basis of patient genomics has implications for precision prescribing of medicines to treat individual patients.

The treatment of rare, monogenic diseases, which often provide too little return on investment to incentivize conventional drug discovery, might benefit because the molecular aetiologies of these diseases are well suited to the discovery of drug repurposing candidates.

Linked biaromatic compounds as cardioprotective agents

Cardiovascular diseases (CVDs) are widespread in the modern world, and their number is constantly growing. For a long time, CVDs have been the leading cause of morbidity and mortality worldwide. Drugs for the treatment of CVD have been developed almost since the beginning of the 20th century, and a large number of effective cardioprotective agents of various classes have been created. Nevertheless, the need for the design and development of new safe drugs for the treatment of CVD remains. Literature data indicate that a huge number of cardioprotective agents of various generations and mechanisms correspond to a single generalized pharmacophore model containing two aromatic nuclei linked by a linear linker. In this regard, we put forward a concept for the design of a new generation of cardioprotective agents with a multitarget mechanism of action within the indicated pharmacophore model. This review is devoted to a generalization of the currently known compounds with cardioprotective properties and corresponding to the pharmacophore model of biaromatic compounds linked by a linear linker. Particular attention is paid to the history of the creation of these drugs, approaches to their design, and analysis of the structure-action relationship within each class.

Cardiovascular Complications of Acetylcholinesterase Inhibitors in Patients with Alzheimer's Disease: A Narrative Review

While acetylcholinesterase inhibitors are used to treat a wide range of patients with Alzheimer's disease, acetylcholinesterase inhibitor use has also been associated with a variety of cardiovascular complications, including bradycardia and syncope. Herein, we review the pathophysiology and clinical evidence for cardiovascular complications caused by acetylcholinesterase inhibitors in patients being treated for dementia and discuss options for their management.

Benefits of pharmacological and electrical cholinergic stimulation in hypertension and heart failure

Systemic arterial hypertension and heart failure are cardiovascular diseases that affect millions of individuals worldwide. They are characterized by a change in the autonomic nervous system balance, highlighted by an increase in sympathetic activity associated with a decrease in parasympathetic activity. Most therapeutic approaches seek to treat these diseases by medications that attenuate sympathetic activity. However, there is a growing number of studies demonstrating that the improvement of parasympathetic function, by means of pharmacological or electrical stimulation, can be an effective tool for the treatment of these cardiovascular diseases. Therefore, this review aims to describe the advances reported by experimental and clinical studies that addressed the potential of cholinergic stimulation to prevent autonomic and cardiovascular imbalance in hypertension and heart failure. Overall, the published data reviewed demonstrate that the use of central or peripheral acetylcholinesterase inhibitors is efficient to improve the autonomic imbalance and hemodynamic changes observed in heart failure and hypertension. Of note, the baroreflex and the vagus nerve activation have been shown to be safe and effective approaches to be used as an alternative treatment for these cardiovascular diseases. In conclusion, pharmacological and electrical stimulation of the parasympathetic nervous system has the potential to be used as a therapeutic tool for the treatment of hypertension and heart failure, deserving to be more explored in the clinical setting.

New horizons in cardiogeriatrics: geriatricians and heart failure care-the custard in the tart, not the icing on the cake

Heart failure (HF) can be considered a disease of older people. It is a leading cause of hospitalisation and is associated with high rates of morbidity and mortality in the over-65s. In 2012, an editorial in this journal detailed the latest HF research and guidelines, calling for greater integration of geriatricians in HF care. This current article reflects upon what has been achieved in this field in recent years, highlighting some future challenges and promising areas. It is written from the perspective of one such integrated team and explores the new role of cardiogeriatrician, working in a multidisciplinary team to deliver and improve care to increasingly complex, older, frail patients with multiple comorbidities who present with primary cardiology problems, especially decompensated HF. Geriatric liaison has improved the care of frail patients in orthopaedics, cancer services, stroke, acute medicine and numerous community settings. We propose that this vital role should now be extended to cardiology teams in general and to HF in particular.

The Neuroinflammasome in Alzheimer's Disease and Cerebral Stroke

Aim/Background

This review investigated a patient with Alzheimer's disease (AD) treated with 4,4′-diaminodiphenyl sulfone (DDS) as a neuroinflammasome competitor.

Methods

We monitored AD's progression through numeric clinical staging (NCS) with a new biomarker. NCS was determined by the presence of AD symptoms and neuropsychiatric (NP) symptoms caused by anti-AD (AAD) drugs (D) as a biomarker. We also monitored the function of DDS for stroke in a no-intake emergency state.

Results

By introducing (D), AD's progression was monitored through NCS staging. AAD side effects and neuropsychiatric symptoms were identified. DDS was stopped in patients with stroke with NCS 6 caused by AAD, and it rapidly proceeded to cerebral infarct.

Conclusions

AAD can occasionally exacerbate AD and stroke. DDS can alleviate mild cognitive impairment (MCI), early AD and stroke. We clinically confirmed the role of DDS as a neuroinflammasome competitor after stroke. DDS preserved neuronal survival within 24–55 h in the Seoul Study cohort.

The Role of Plasma Neurofilament Light Protein for Assessing Cognitive Impairment in Patients With End-Stage Renal Disease

Introduction: End-stage renal disease (ESRD) is defined as the irreversible loss of renal function, necessitating renal replacement therapy. Patients with ESRD tend to have more risk factors for cognitive impairment than the general population, including hypertension, accumulative uremic toxin, anemia, and old age. The association between these risk factors and the pathologic protein was lacking. Blood-based assays for detecting pathologic protein, such as amyloid beta (Aβ), total tau protein, and neurofilament light chain (NfL), have the advantages of being less invasive and more cost-effective for diagnosing patients with cognitive impairment. The aim of the study is to validate if the common neurologic biomarkers were different in ESRD patients and to differentiate if the specific biomarkers could correlate with specific correctable risk factors. Methods: In total, 67 participants aged >45 years were enrolled. The definition of ESRD was receiving maintenance hemodialysis for >3 months. Cognitive impairment was defined as a Mini-Mental State Examination score of <24. The participants were divided into groups for ESRD with and without cognitive impairment. The blood-based biomarkers (tau protein, Aβ1/40, Aβ1/42, and NfL) were analyzed through immunomagnetic reduction assay. Other biochemical and hematologic data were obtained simultaneously. Summary of results: The study enrolled 43 patients with ESRD who did not have cognitive impairment and 24 patients with ESRD who had cognitive impairment [Mini-Mental State Examination (MMSE): 27.60 ± 1.80 vs. 16.84 ± 6.40, p < 0.05]. Among the blood-based biomarkers, NfL was marginally higher in the ESRD with cognitive impairment group than in the ESRD without cognitive impairment group (10.41 ± 3.26 vs. 8.74 ± 2.81 pg/mL, p = 0.037). The concentrations of tau protein, amyloid β 1/42, and amyloid β 1/40 (p = 0.504, 0.393, and 0.952, respectively) were similar between the two groups. The area under the curve of NfL to distinguish cognitively impaired and unimpaired ESRD patients was 0.687 (95% confidence interval: 0.548-0.825, p = 0.034). There was no correlation between the concentration of NfL and MMSE among total population (r = -0.153, p = 0.277), patients with (r = 0.137, p = 0.583) or without cognitive impairment (r = 0.155, p = 0.333). Conclusion: Patients with ESRD who had cognitive impairment had marginally higher plasma NfL concentrations. NfL concentration was not correlated with the biochemical parameters, total MMSE among total population or individual groups with or without cognitive impairment. The concentrations of Aβ1/40, Aβ1/42, and tau were similar between the groups.

The Association Between the Use of Cholinesterase Inhibitors and Cardiovascular Events Among Older Patients With Alzheimer Disease

OBJECTIVE

To evaluate the association between the use of cholinesterase inhibitors (ChEIs) and incident cardiovascular events (CVEs) among older patients with Alzheimer disease (AD).

PATIENTS AND METHODS

This retrospective cohort study was conducted with a new-user design and active-comparator design. The data source was the 2005-2014 Full Population file from the Health and Welfare Database in Taiwan. Patients were included if they were aged 50 years or older and had been diagnosed with AD between January 1, 2006, and December 31, 2010. The association between ChEI use and the risk of CVEs was investigated in patients with AD. Among the ChEI users, the risk of CVEs was further compared between patients with different cumulative doses and different ChEI treatment strategies. The propensity score method, which included matching and inverse probability of treatment weighting, was used to balance the potential confounders. A Cox proportional hazards model with competing risks was used to estimate the hazard ratio of CVEs.

RESULTS

The study included 6070 patients with AD. After covariate adjustment, ChEI users had a significantly lower risk of CVEs than nonusers (hazard ratio, 0.57; 95% CI, 0.51 to 0.62). Among ChEI users, patients with a high cumulative dose had a significantly lower risk of CVEs than those with a low cumulative dose (hazard ratio, 0.82; 95% CI, 0.70 to 0.96).

CONCLUSION

The use of ChEIs was associated with a decreased risk of incident CVEs among patients with AD. The cardioprotective effect of ChEIs showed a dose-response relationship.

Characteristic Effects of the Cardiac Non-Neuronal Acetylcholine System Augmentation on Brain Functions

Since the discovery of non-neuronal acetylcholine in the heart, this specific system has drawn scientific interest from many research fields, including cardiology, immunology, and pharmacology. This system, acquired by cardiomyocytes independent of the parasympathetic nervous system of the autonomic nervous system, helps us to understand unsolved issues in cardiac physiology and to realize that the system may be more pivotal for cardiac homeostasis than expected. However, it has been shown that the effects of this system may not be restricted to the heart, but rather extended to cover extra-cardiac organs. To this end, this system intriguingly influences brain function, specifically potentiating blood brain barrier function. Although the results reported appear to be unusual, this novel characteristic can provide us with another research interest and therapeutic application mode for central nervous system diseases. In this review, we discuss our recent studies and raise the possibility of application of this system as an adjunctive therapeutic modality.

Long term use of donepezil and QTc prolongation

BACKGROUND

The neurocognitive benefits of donepezil are well recognised, but the potential side effects on cardiac conduction remain unclear.

OBJECTIVE

To investigate whether long-term donepezil therapy is associated with electrocardiographic (ECG) changes and in particular to assess its effects on the QT interval.

METHODS

We conducted a single centre retrospective analysis of patients admitted to our trust on donepezil therapy over a 12-month period. An admission resting 12-lead ECG was obtained and compared to their ECG prior to commencement of donepezil therapy to assess for any significant difference in ECG parameters.

RESULTS

We identified 59 patients suitable for analysis. PR (177.0 ± 29.0 ms vs. 186.1 ± 34.2 ms, p = 0.04), QRS (101.7 ± 20.3 ms vs. 104.7 ± 22.3 ms, p = 0.04) and QT (393.3 ± 35.6 ms vs. 411.9 ± 44.6 ms, p = 0.002) interval prolongation were all associated with donepezil use. The increase in QT intervals remained significant on correction for heart rate; resulting in 8 (13.6%) patients developing high arrhythmogenic risk based on assessment using QT nomogram plots. Concomitant use of tricyclic antidepressants was associated with significant QT prolongation (QTcB: r _pb = 0.344, p = 0.008, QTcFred: r _pb = 0.382, p = 0.003, QTcFram: r _pb = 0.379, p = 0.003, QTcH: r _pb = 0.352, p = 0.006), while the use of rate-limiting calcium channel blockers was associated with significant PR prolongation (r _pb = 0.314, p = 0.030), and beta-blockers with a reduction in heart rate (r _pb = 0.256, p = 0.050).

CONCLUSION

Our results clearly demonstrate that long-term use of donepezil is associated with prolongation of the QT interval. We suggest ECG evaluation should take place before and after donepezil initiation, and clinicians should be even more vigilant in those prescribed tricyclic antidepressants.

The effects of acetylcholinesterase inhibitors on the heart in acute myocardial infarction and heart failure: From cells to patient reports

Cardiovascular diseases remain a major cause of morbidity and mortality worldwide. Cardiovascular diseases such as acute myocardial infarction, ischaemia/reperfusion injury and heart failure are associated with cardiac autonomic imbalance characterized by sympathetic overactivity and parasympathetic withdrawal from the heart. Increased parasympathetic activity by electrical vagal nerve stimulation has been shown to provide beneficial effects in the case of cardiovascular diseases in both animals and patients by improving autonomic function, cardiac remodelling and mitochondrial function. However, clinical limitations for electrical vagal nerve stimulation exist because of its invasive nature, costly equipment and limited clinical validation. Therefore, novel therapeutic approaches which moderate parasympathetic activities could be beneficial for in the case of cardiovascular disease. Acetylcholinesterase inhibitors inhibit acetylcholinesterase and hence increase cholinergic transmission. Recent studies have reported that acetylcholinesterase inhibitors improve autonomic function and cardiac function in cardiovascular disease models. Despite its potential clinical benefits for cardiovascular disease patients, the role of acetylcholinesterase inhibitors in acute myocardial infarction and heart failure remediation remains unclear. This article comprehensively reviews the effects of acetylcholinesterase inhibitors on the heart in acute myocardial infarction and heart failure scenarios from in vitro and in vivo studies to clinical reports. The mechanisms involved are also discussed in this review.

Heart Failure and Cognitive Impairment: Clinical Relevance and Therapeutic Considerations

Heart failure (HF) is a devastating condition characterized by poor quality of life, numerous complications, high rate of readmission and increased mortality. HF is the most common cause of hospitalization in the United States especially among people over the age of 64 years. The number of people grappling with the ill effects of HF is on the rise as the number of people living to an old age is also on the increase.

Several factors have been attributed to these high readmission and mortality rates among which are; poor adherence with therapy, inability to keep up with clinic appointments and even failure to recognize early symptoms of HF deterioration which may be a result of cognitive impairment.

Therefore, this review seeks to compile the most recent information about the links between HF and dementia or cognitive impairment. We also assessed the prognostic consequences of cognitive impairment complicating HF, therapeutic strategies among patients with HF and focus on future areas of research that would reduce the prevalence of cognitive impairment, reduce its severity and also ameliorate the effect of cognitive impairment coexisting with HF.

Alzheimer's disease medication and risk of all-cause mortality and all-cause hospitalization: A retrospective cohort study

Introduction

Identifying Alzheimer's disease (AD) pharmacologic treatment options that effectively reduce the risk of mortality and hospitalization in real-world settings is critical.

Methods

We compared donepezil, galantamine, memantine, oral rivastigmine, and transdermal rivastigmine with regard to all-cause mortality and all-cause hospitalization risk among fee-for-service Medicare beneficiaries with AD (aged ≥ 65 years) using a retrospective cohort study design. Our primary analysis was based on intention to treat (ITT), but we also present as-treated analysis.

Results

In our final study sample (N = 21,558), significant difference in survival among index AD medication groups were observed with donepezil being associated with better survival than memantine, and oral and transdermal forms of rivastigmine for both ITT and as-treated analysis. Difference in hazards of all-cause hospitalization among index AD medication groups was observed in ITT analysis but not in as-treated analysis.

Discussion

Significant differences exist in terms of mortality and hospitalization risk with different AD medication initiation in real-world setting.

Cardiac 11C-Donepezil Binding Increases With Age in Healthy Humans: Potentially Signifying Sigma-1 Receptor Upregulation

BACKGROUND

Donepezil may have cardioprotective properties, but the mechanism is unclear. Using positron-emission tomography (PET), we explored 11C-donepezil uptake in the heart of humans in relation to age. The results are discussed in the context of the cardioprotective property of donepezil.

METHODS

We included data from 57 patients with cardiac 11C-donepezil PET scans. Linear regression analyses were performed to explore the correlation between cardiac 11C-donepezil standardized uptake value (SUV) and age. Subgroup analyses were performed for healthy controls, patients with prodromal or diagnosed Parkinson disease (PD), males, and females.

RESULTS

In the total group of 57 patients, linear regression analysis revealed a significant positive correlation between cardiac 11C-donepezil uptake and age ( r2 = .63, P < .0001). The average increase was ≈1.25 SUV per decade and a 2-fold increase in SUV from age 30 to 65 years. Subgroup analyses also showed significant correlations: healthy control patients alone (n = 28, r2 = .73, P < .0001), prodromal or diagnosed PD (n = 29, r2 = .28, P = .03), male patients (n = 34, r2 = .49, P < .0001), and female patients (n = 23, r2 = .82, P < .0001). No other organs showed increased 11C-donepezil binding with age.

CONCLUSIONS

11C-donepezil SUV increases robustly with age in the normal human heart. We speculate that the increased donepezil binding is caused primarily by sigma-1 receptor upregulation. If our interpretation is correct, it shows that sigma-1 receptors are dynamically regulated and may represent an overlooked target for pharmacological intervention studies.

The non-neuronal cholinergic system in the heart: A comprehensive review

The autonomic influences on the heart have a ying-yang nature, albeit oversimplified, the interplay between the sympathetic and parasympathetic system (known as the cholinergic system) is often complex and remain poorly understood. Recently, the heart has been recognized to consist of neuronal and non-neuronal cholinergic system (NNCS). The existence of cardiac NNCS has been confirmed by the presence of cholinergic markers in the cardiomyocytes, which are crucial for synthesis (choline acetyltransferase, ChAT), storage (vesicular acetylcholine transporter, VAChT), reuptake of choline for synthesis (high-affinity choline transporter, CHT1) and degradation (acetylcholinesterase, AChE) of acetylcholine (ACh). The non-neuronal ACh released from cardiomyocytes is believed to locally regulate some of the key physiological functions of the heart, such as regulation of heart rate, offsetting hypertrophic signals, maintenance of action potential propagation as well as modulation of cardiac energy metabolism via the muscarinic ACh receptor in an auto/paracrine manner. Apart from this, several studies have also provided evidence for the beneficial role of ACh released from cardiomyocytes against cardiovascular diseases such as sympathetic hyperactivity-induced cardiac remodeling and dysfunction as well as myocardial infarction, confirming the important role of NNCS in disease prevention. In this review, we aim to provide a fundamental overview of cardiac NNCS, and information about its physiological role, regulatory factors as well as its cardioprotective effects. Finally, we propose the different approaches to target cardiac NNCS as an adjunctive treatment to specifically address the withdrawal of neuronal cholinergic system in cardiovascular disease such as heart failure.

The Impact of a Long-Term Rivastigmine and Donepezil Treatment on All-Cause Mortality in Patients With Alzheimer's Disease

Cholinesterase inhibitors (ChEIs) are the mainstays of symptomatic treatment of Alzheimer's disease (AD); however, their efficacy is limited, and their use was associated with deaths in some groups of patients. The aim of the current study was to assess the impact of the long-term use of ChEIs on mortality in patients with AD. This observational, longitudinal study included 1171 adult patients with a diagnosis of AD treated with donepezil or rivastigmine. Each patient was observed for 24 months or until death. The cognitive and functional assessments, the use of ChEIs, memantine, antipsychotics, antidepressants, and anxiolytics were recorded. The total number of deaths at the end of the observational period was 99 (8.45%). The patients who had received rivastigmine treatment were at an increased risk of death in the follow-up period. The higher risk of death in the rivastigmine group remained significant in multivariate Cox regression models.

Acetylcholinesterase Inhibitors: Beneficial Effects on Comorbidities in Patients With Alzheimer's Disease

Elderly patients with Alzheimer's disease (AD) and other dementias are at high risk of polypharmacy and excessive polypharmacy for common coexisting medical conditions. Polypharmacy increases the risk of drug-drug and drug-disease interactions in these patients who may not be able to communicate early symptoms of adverse drug events. Three acetylcholinesterase inhibitors (ACHEIs) have been approved for AD: donepezil (Aricept), rivastigmine (Exelon), and galantamine (Razadyne). They are also used off-label for other causes of dementia such as Lewy body and vascular dementia. We here report evidence from the literature that ACHEI treatment, prescribed for cognitive impairment, can reduce the load of medications in patients with AD by also addressing cardiovascular, gastrointestinal, and other comorbidities. Using one drug to address multiple symptoms can reduce costs and improve medication compliance.

The autonomic nervous system as a therapeutic target in heart failure: a scientific position statement from the Translational Research Committee of the Heart Failure Association of the European Society of Cardiology

Despite improvements in medical therapy and device-based treatment, heart failure (HF) continues to impose enormous burdens on patients and health care systems worldwide. Alterations in autonomic nervous system (ANS) activity contribute to cardiac disease progression, and the recent development of invasive techniques and electrical stimulation devices has opened new avenues for specific targeting of the sympathetic and parasympathetic branches of the ANS. The Heart Failure Association of the European Society of Cardiology recently organized an expert workshop which brought together clinicians, trialists and basic scientists to discuss the ANS as a therapeutic target in HF. The questions addressed were: (i) What are the abnormalities of ANS in HF patients? (ii) What methods are available to measure autonomic dysfunction? (iii) What therapeutic interventions are available to target the ANS in patients with HF, and what are their specific strengths and weaknesses? (iv) What have we learned from previous ANS trials? (v) How should we proceed in the future?

Various Regulatory Modes for Circadian Rhythmicity and Sexual Dimorphism in the Non-Neuronal Cardiac Cholinergic System

Cardiomyocytes possess a non-neuronal cardiac cholinergic system (NNCCS) regulated by a positive feedback system; however, its other regulatory mechanisms remain to be elucidated, which include the epigenetic control or regulation by the female sex steroid, estrogen. Here, the NNCCS was shown to possess a circadian rhythm; its activity was upregulated in the light-off phase via histone acetyltransferase (HAT) activity and downregulated in the light-on phase. Disrupting the circadian rhythm altered the physiological choline acetyltransferase (ChAT) expression pattern. The NNCCS circadian rhythm may be regulated by miR-345, independently of HAT, causing decreased cardiac ChAT expression. Murine cardiac ChAT expression and ACh contents were increased more in female hearts than in male hearts. This upregulation was downregulated by treatment with the estrogen receptor antagonist tamoxifen, and in contrast, estrogen reciprocally regulated cardiac miR-345 expression. These results suggest that the NNCCS is regulated by the circadian rhythm and is affected by sexual dimorphism.

Impact of acetylcholinesterase inhibitors on the occurrence of acute coronary syndrome in patients with dementia

The study aimed to investigate the association of acetylcholinesterase inhibitors (AChEIs) use with the risk of acute coronary syndrome (ACS). We conducted a population-based retrospective cohort study of dementia patients during 1 January 1999 to 31 December 2008 using the National Health Insurance Database in Taiwan. New AChEI users during the study period were matched with AChEI nonusers in age-matched and gender-matched cohorts. The risk of ACS associated with use of AChEIs was analyzed using modified Kaplan-Meier analysis and Cox proportional hazard models after adjustment for competing death risk. Use of AChEIs was associated with a lower incidence of ACS (212.8/10,000 person-years) compared to the matched reference cohort (268.7/10,000 person-years). The adjusted hazard ratio for ACS in patients with dementia treated with AChEIs was 0.836 (95% confidence interval, 0.750–0.933; P < 0.001). Further sensitivity analysis of different study populations demonstrated consistent results. A statistical dose–response relationship for AChEI use and ACS risk was significant for the patients with dementia. In patients with dementia, AChEI treatment was associated with decreased risk of ACS.

Acetylcholinesterase Inhibition Attenuates the Development of Hypertension and Inflammation in Spontaneously Hypertensive Rats

BACKGROUND

It is hypothesized that chronic increase of availability of acetylcholine, resulting from the effect of antiacetylcholinesterases, may prevent autonomic imbalance and reduce inflammation yielding benefic effects for cardiovascular disorders in hypertension. The effect of long-term administration of antiacetylcholinesterase agents with central and/or peripheral action, i.e., donepezil and pyridostigmine, were investigated on arterial pressure (AP), sympathovagal balance, plasma cytokine levels, and cardiac remodeling in spontaneously hypertensive rats (SHR).

METHODS

Chronic treatment with donepezil or pyridostigmine started before the onset of hypertension. AP was measured by plethysmography every 4 weeks. At the end of 16 weeks of treatment, methylatropine was used to evaluate the cardiac vagal tone; AP and pulse interval (PI) variability were also evaluated followed by plasma and heart collection for analysis.

RESULTS

Pyridostigmine, which does not cross the blood-brain barrier, increased cardiac vagal tone, and reduced cardiomyocyte diameter and collagen density, but did not affect the AP and plasma cytokine levels. Donepezil, which crosses the blood-brain barrier, attenuated the development of hypertension, increased cardiac vagal tone, and improved AP and PI variability. Likewise, donepezil reduced the plasma levels of tumor necrosis factor-α, interleukin 6, and interferon γ, besides reducing cardiomyocyte diameter and collagen density.

CONCLUSIONS

Donepezil attenuated the development of hypertension in SHR probably involving antiinflammatory effects, indicating that acetylcholinesterase inhibition yields benefic effects for antihypertensive therapy.

Heart failure and Alzheimer's disease

It has recently been proposed that heart failure is a risk factor for Alzheimer's disease. Decreased cerebral blood flow and neurohormonal activation due to heart failure may contribute to the dysfunction of the neurovascular unit and cause an energy crisis in neurons. This leads to the impaired clearance of amyloid beta and hyperphosphorylation of tau protein, resulting in the formation of amyloid beta plaques and neurofibrillary tangles. In this article, we will summarize the current understanding of the relationship between heart failure and Alzheimer's disease based on epidemiological studies, brain imaging research, pathological findings and the use of animal models. The importance of atherosclerosis, myocardial infarction, atrial fibrillation, blood pressure and valve disease as well as the effect of relevant medications will be discussed.

Donepezil and life expectancy in Alzheimer's disease: a retrospective analysis in the Tajiri Project

Background

Cholinesterase inhibitors (ChEIs) such as donepezil have the effect of delaying progression of Alzheimer’s disease (AD), but their effect on life expectancy is unclear. We analyzed the influence of donepezil on life expectancy after onset of AD, together with the effects of antipsychotic drugs and residency in a nursing home.

Methods

All outpatients at the Tajiri Clinic from 1999–2012 with available medical records and death certificates were included in a retrospective analysis. The entry criteria were a dementia diagnosis based on DSM-IV criteria and diagnosis of AD using NINCDS-ADRDA criteria; medical treatment for more than 3 months; and follow up until less than 1 year before death.

Results

We identified 390 subjects with medical records and death certificates, of whom 275 had a diagnosis of dementia that met the entry criteria. Of 100 patients diagnosed with AD, 52 had taken donepezil and 48 patients had not received the drug due to treatment prior to the introduction of donepezil in 1999 in Japan. The lifetime expectancies after onset were 7.9 years in the donepezil group and 5.3 years in the non-donepezil group. There was a significant drug effect with a significant covariate effect of nursing home residency. Other covariates did not reach a significant level.

Conclusions

Although this report has the limitation of all retrospective analyses: the lack of randomization, we found a positive effect of donepezil on lifetime expectancy after onset of AD. This may be due to a decreased mortality rate caused by reduction of concomitant diseases such as pneumonia. The similar life expectancies in patients taking donepezil at home and those not taking donepezil in a nursing home indicated a positive health economic effect of the drug.

Cardioprotection and anticholinesterases in patients with Alzheimer's disease: time for reappraisal

Background/Aim

Traditional risk factors, like impaired transmitral flow in diastolic filling [vortex formation time (VFT) as echocardiographic parameter], contribute to Alzheimer's disease (AD). Moreover, we observed that acetylcholinesterase inhibitors provide a significant cardioprotection. We assessed the pathogenetic role of VFT as early cardiovascular risk factor in 23 AD patients and 24 controls.

Results

The results showed no statistical difference between the two groups, but the VFT values were significantly lower in nontreated AD patients, and higher value were observed in AD patients treated with anticholinesterases.

Conclusions

The results support the beneficial effects of anticholinesterases on the cardiovascular system of AD patients. Thus, the transition to evidence-based medicine and an in vivo model of cardiomyocytes might strengthen these results.

Influences of donepezil on cardiovascular system--possible therapeutic benefits for heart failure--donepezil cardiac test registry (DOCTER) study

To study prospectively influences of donepezil, an acetylcholinesterase inhibitor against Alzheimer disease, on cardiovascular system, we evaluated cardiovascular changes occurring during new initialized treatment with donepezil in 49 dementia patients over 6 months. No patient suffered from cardiovascular events. In clinical changes between baseline and the first evaluation after donepezil treatment, heart rate and plasma brain natriuretic peptide (BNP) levels as a marker for heart failure did not change (BNP: 59.62 ± 62.71 pg/mL at baseline to 53.18 ± 42.34 pg/mL at first evaluation; P = 0.262). We further examined plasma BNP levels in 2 groups into which the patients were divided at baseline according to the cut-off plasma BNP level of 60 pg/mL. In patients with high level of BNP, the BNP levels decreased after administration of donepezil (116.39 ± 76.58 pg/mL at baseline to 82.24 ± 46.64 pg/mL at first evaluation; P = 0.011) with the tendency to be reduced in the follow-up period. BNP did not change in patients with low level of BNP. Donepezil seemed to be safe in patients with dementia without symptomatic heart disease and significantly decreased plasma BNP levels in patients with subclinical chronic heart failure.

QT dispersion in mild cognitive impairment: a possible tool for predicting the risk of progression to dementia?

OBJECTIVE

The aim of this research was to investigate relationships between cognitive function and non-invasive, repeatable cardiac parameters in elderly subjects suffering from mild cognitive impairment (MCI) or Alzheimer's disease (AD).

METHODS

Two hundred and twenty-four community-living elderly subjects, 31 AD patients, 77 MCI patients, and 116 cognitively normal subjects (CNS), were evaluated for cognitive abilities (Mini Mental State Examination score (MMSE)) and for electrocardiographic [corrected heart rate QT interval dispersion (QTcD)] and echocardiographic [Left ventricular ejection fraction (LVEF)] parameters.

RESULTS

Mean values of LVEF were not significantly different between the three groups; QTcD mean values were significantly lower in CNS group than in subjects with MCI and AD. The Pearson Product Moment Correlation test, carried out in the three study groups, showed a significant inverse correlation between QTcD and MMSE score (r = -0.357; p < 0.01) in the group of MCI patients, only. In multivariable-adjusted linear regression tests, QTcD (p = 0.030) and education (p = 0.021) are associated with MMSE score in MCI group. Only the parameter of education appears to predict MMSE in CNS group; none of these parameters appear to predict MMSE in the group of patients with AD.

CONCLUSION

The association between QTcD and MMSE requires cautious interpretation and further extensive investigation. However, if confirmed by longitudinal studies, the finding could play a role in the management of the subjects with MCI.

Use of rivastigmine or galantamine and risk of adverse cardiac events: a database study from the Netherlands

BACKGROUND

Two cholinesterase inhibitors (ChEIs), rivastigmine and galantamine, are used to treat Alzheimer disease in the Netherlands. Several adverse cardiac events have been reported for these medications.

OBJECTIVE

We aimed to assess if the use of ChEIs increased the risk of cardiac events in the Netherlands.

METHODS

A cohort crossover study of the PHARMO Record Linking System database included patients who initiated ChEIs at age 50 years or older, had at least 1 dispensing of a ChEI drug between 1998 and 2008, a 1-year history in PHARMO, and 1 subsequent dispensing of any medication. Two outcomes were assessed: a first hospitalization for syncope or atrioventricular block. Poisson and Cox regression were used to calculate incidence densities and hazard ratios for cardiac events during periods with ChEI use, compared with periods without ChEI use.

RESULTS

During the complete observation period of 8.9 years (interquartile range 6.7 to 10.2) there were 132 first hospitalizations for atrioventricular block and 17 first hospitalizations for syncope among 3358 patients. The adjusted incidence densities were significantly increased during ChEI exposure for syncope and atrioventricular block, when compared with the background incidence densities in the roughly 5 years before the last year before ChEI initiation. However, when exposed periods were compared with the unexposed periods 1 year before ChEI initiation and times after exposure, the adjusted hazard ratios remained increased for syncope and atrioventricular block, but increases were not significant anymore.

CONCLUSIONS

Exposure to ChEIs might increase the risk of adverse cardiac events, but small numbers of cases limit conclusions about the risk in this population and research on larger study samples is needed.

RGS Proteins in Heart: Brakes on the Vagus

It has been nearly a century since Otto Loewi discovered that acetylcholine (ACh) release from the vagus produces bradycardia and reduced cardiac contractility. It is now known that parasympathetic control of the heart is mediated by ACh stimulation of G(i/o)-coupled muscarinic M2 receptors, which directly activate G protein-coupled inwardly rectifying potassium (GIRK) channels via Gβγ resulting in membrane hyperpolarization and inhibition of action potential (AP) firing. However, expression of M2R-GIRK signaling components in heterologous systems failed to recapitulate native channel gating kinetics. The missing link was identified with the discovery of regulator of G protein signaling (RGS) proteins, which act as GTPase-activating proteins to accelerate the intrinsic GTPase activity of Gα resulting in termination of Gα- and Gβγ-mediated signaling to downstream effectors. Studies in mice expressing an RGS-insensitive Gα(i2) mutant (G184S) implicated endogenous RGS proteins as key regulators of parasympathetic signaling in heart. Recently, two RGS proteins have been identified as critical regulators of M2R signaling in heart. RGS6 exhibits a uniquely robust expression in heart, especially in sinoatrial (SAN) and atrioventricular nodal regions. Mice lacking RGS6 exhibit increased bradycardia and inhibition of SAN AP firing in response to CCh as well as a loss of rapid activation and deactivation kinetics and current desensitization for ACh-induced GIRK current (I(KACh)). Similar findings were observed in mice lacking RGS4. Thus, dysregulation in RGS protein expression or function may contribute to pathologies involving aberrant electrical activity in cardiac pacemaker cells. Moreover, RGS6 expression was found to be up-regulated in heart under certain pathological conditions, including doxorubicin treatment, which is known to cause life-threatening cardiotoxicity and atrial fibrillation in cancer patients. On the other hand, increased vagal tone may be cardioprotective in heart failure where acetylcholinesterase inhibitors and vagal stimulation have been proposed as potential therapeutics. Together, these studies identify RGS proteins, especially RGS6, as new therapeutic targets for diseases such as sick sinus syndrome or other maladies involving abnormal autonomic control of the heart.

Cognitive Enhancers in Moderate to Severe Alzheimer's Disease

The treatment of moderate to severe Alzheimer's disease is reviewed with regard to mechanisms of action, pharmacokinetics, metabolism, safety/tolerability, and efficacy in reducing cognitive, behavioral/psychiatric, functional and global symptoms. The cholinesterase inhibitors donepezil, rivastigmine and galantamine and the N-methyl-d-aspartate receptor channel blocker memantine are moderately beneficial. Small improvements over a few months are followed by slowed mental decline. Concerning cognitive, functional and global functions, these drugs are similarly effective. Cholinesterase inhibitors also reduce apathy, memantine counteracts agitation and aggression. Serious adverse effects are rare with all four drugs. Cholinesterase inhibitors bear a risk for patients with cardiac diseases. Adverse emetic events are typical for oral formulations of these drugs, but less for rivastigmine transdermal patches. Other routes of administration and use of a galantamine prodrug are currently investigated. The superiority of combination therapies over monotherapies requires further support. Promising investigational drugs include the copper/zinc ionophore PBT2 and multifunctional hybrid molecules.

Donepezil, anti-Alzheimer's disease drug, prevents cardiac rupture during acute phase of myocardial infarction in mice

BACKGROUND

We have previously demonstrated that the chronic intervention in the cholinergic system by donepezil, an acetylcholinesterase inhibitor, plays a beneficial role in suppressing long-term cardiac remodeling after myocardial infarction (MI). In comparison with such a chronic effect, however, the acute effect of donepezil during an acute phase of MI remains unclear. Noticing recent findings of a cholinergic mechanism for anti-inflammatory actions, we tested the hypothesis that donepezil attenuates an acute inflammatory tissue injury following MI.

METHODS AND RESULTS

In isolated and activated macrophages, donepezil significantly reduced intra- and extracellular matrix metalloproteinase-9 (MMP-9). In mice with MI, despite the comparable values of heart rate and blood pressure, the donepezil-treated group showed a significantly lower incidence of cardiac rupture than the untreated group during the acute phase of MI. Immunohistochemistry revealed that MMP-9 was localized at the infarct area where a large number of inflammatory cells including macrophages infiltrated, and the expression and the enzymatic activity of MMP-9 at the left ventricular infarct area was significantly reduced in the donepezil-treated group.

CONCLUSION

The present study suggests that donepezil inhibits the MMP-9-related acute inflammatory tissue injury in the infarcted myocardium, thereby reduces the risk of left ventricular free wall rupture during the acute phase of MI.