PCSK9 inhibition with orally administered NNC0385-0434 in hypercholesterolaemia: a randomised, double-blind, placebo-controlled and active-controlled phase 2 trial

BACKGROUND

Currently available injectable drugs that target proprotein convertase subtilisin/kexin type 9 (PCSK9) reduce serum LDL cholesterol and improve cardiovascular outcomes. This phase 2 study assessed NNC0385-0434, an oral PCSK9 inhibitor, in individuals receiving oral lipid-lowering therapy.

METHODS

In this randomised, double-blind, placebo-controlled and active-controlled trial, 42 research sites across seven countries (Belgium, Germany, Greece, Japan, the Netherlands, Poland, and the USA) recruited individuals with established atherosclerotic cardiovascular disease (aged ≥40 years) or at high risk of atherosclerotic cardiovascular disease (aged >50 years), who had LDL cholesterol concentration of at least 1·8 mmol/L and were receiving maximum tolerated statins and stable lipid-lowering therapy. The study randomly allocated participants (3:1) with an interactive web response system to receive either NNC0385-0434 (15 mg, 40 mg, or 100 mg) once a day co-formulated with the oral absorption enhancer sodium N-[8-(2-hydroxybenzoyl)amino] caprylate (500 mg); placebo; or open-label evolocumab (140 mg) every 2 weeks administered subcutaneously. Blinding was performed within each dose level. The primary endpoint was percentage change from baseline in LDL cholesterol measured by β quantification at week 12. All randomly assigned participants received at least one dose of treatment and were included in both safety and efficacy analyses. The trial was registered on ClinicalTrials.gov, NCT04992065, and is completed.

FINDINGS

Between Aug 16, 2021, and Jan 28, 2022, we randomly assigned 267 patients to one of the three NNC0385-0434 dose cohorts (n=53 per cohort), matching placebo (n=54), or open-label evolocumab (n=54). The study population comprised 82 (31%) women and 185 (69%) men; mean age was 64·3 years (SD 9·0). Baseline mean LDL cholesterol concentration was 2·7 mmol/L (SD 0·8). Treatment with NNC0385-0434 resulted in reductions in LDL cholesterol from baseline to week 12, of 32·0 percentage points (95% CI 20·9 to 43·0) in the 15 mg cohort, 44·9 percentage points (33·8 to 56·0) in the 40 mg cohort, and 61·8 percentage points (50·7 to 72·9) in the 100 mg cohort, compared with the placebo group (p<0·0001 for each). Patients treated with evolocumab had similar LDL cholesterol reductions (59·6% [SE 4·1] decrease from baseline) to patients receiving NNC0385-0434 100 mg (56·2% [4·0]). The estimated treatment difference between NNC0385-0434 100 mg and evolocumab 140 mg was 3·4 percentage points [95% CI -7·8 to 14·7]. The most frequently reported adverse event was COVID-19, which affected 31 (12%) of 267 patients, with similar numbers across treatment groups. Investigative sites reported gastrointestinal disorders as the most frequent treatment-related adverse event (26 patients and 35 events total in the three NNC0385 cohorts and one patient and one event each in the placebo and evolocumab cohorts). No deaths or treatment-related serious adverse events occurred.

INTERPRETATION

This study showed excellent 12-week LDL cholesterol lowering efficacy and good patient tolerance of an oral PCSK9 inhibitor, NNC0835-0434, similar to an injectable drug. However, the sponsor chose to discontinue further development of NNC0835-0434 due to portfolio considerations.

FUNDING

Novo Nordisk.

Nutraceutical approaches to non-alcoholic fatty liver disease (NAFLD): A position paper from the International Lipid Expert Panel (ILEP)

Non-Alcoholic Fatty Liver Disease (NAFLD) is a common condition affecting around 10-25% of the general adult population, 15% of children, and even > 50% of individuals who have type 2 diabetes mellitus. It is a major cause of liver-related morbidity, and cardiovascular (CV) mortality is a common cause of death. In addition to being the initial step of irreversible alterations of the liver parenchyma causing cirrhosis, about 1/6 of those who develop NASH are at risk also developing CV disease (CVD). More recently the acronym MAFLD (Metabolic Associated Fatty Liver Disease) has been preferred by many European and US specialists, providing a clearer message on the metabolic etiology of the disease. The suggestions for the management of NAFLD are like those recommended by guidelines for CVD prevention. In this context, the general approach is to prescribe physical activity and dietary changes the effect weight loss. Lifestyle change in the NAFLD patient has been supplemented in some by the use of nutraceuticals, but the evidence based for these remains uncertain. The aim of this Position Paper was to summarize the clinical evidence relating to the effect of nutraceuticals on NAFLD-related parameters. Our reading of the data is that whilst many nutraceuticals have been studied in relation to NAFLD, none have sufficient evidence to recommend their routine use; robust trials are required to appropriately address efficacy and safety.

Prevalence and Impact of Atrial Fibrillation on Intra-Hospital Mortality in Patients Aged ≥75 Years

It is unclear whether the association between atrial fibrillation (AF) and intra-hospital mortality in patients aged 75 years and older is causal or not. This study aims (1) to describe the prevalence and clinical characteristics of AF in ≥75-year-old inpatients and (2) to study the association between AF and length of stay (LOS) and intra-hospital mortality. This retrospective cohort study includes consecutive patients aged ≥75 years admitted between January 2017 and December 2019 to a Belgian secondary hospital. Survival analysis was conducted on the whole dataset and a propensity score-matched dataset separately. Propensity score matching (PSM) was performed to account for the individual probability of having AF given a set of covariates. In 9,105 patients, 3,137 (34%) had a diagnosis of AF upon hospital admission. AF prevalence increased with age strata (from 29% to 38%), and Charlson Co-morbidity Index (from 28% to 57%). Intra-hospital mortality (20%) was higher in the AF group than in the AF-free group (25% vs 17%, p <0.001). The median LOS was 11 days and was shorter in those without AF (10 [4, 17] days) compared with those with AF (11 [5, 19], p <0.001). After PSM, AF was not associated with increased odds of LOS >10 days (odds ratio 1.08, confidence interval: 0.98 to 1.20, p = 0.13). The risk of intra-hospital death for patients with AF remained higher compared with those without AF (log-rank p = 0.0015 and hazard ratio 1.17; confidence interval: 1.04 to 1.32, p = 0.008). In conclusion, the prevalence of AF was high (34%) in inpatients aged ≥75 years and increased with age and co-morbidity burden. After PSM, patients with AF had a 17% higher risk of intra-hospital mortality than patients without AF.

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.

Implementation of clinical practices and pathways optimizing ACS patients lipid management: Focus on eight European initiatives

Post-acute coronary syndrome (ACS) patients are at very high cardiovascular risk. Despite current guidelines strongly recommend to reduce LDL-C levels and initiation of high-intensity statins as early as possible in patients admitted with an ACS, less than half of ACS patients receive a high intensity statin, and a high percentage of has LDL-C well above the goal despite therapy. There are multiple reasons for that, including physician lack of guideline adherence, patient lack of compliance with treatment, and lack of standardized procedures. Furthermore, although the prevalence of familial hypercholesterolemia is higher among patients with ACS, this condition remains poorly estimated. To fill these gaps, some European countries have launched local initiatives for the in-hospital and post-discharge ACS patient lipid management. It appears that ensuring optimal therapy during hospitalization and dedicated follow-up protocols results in a significant improvement of lipid levels in these very high risk patients, which may translate into a reduced risk of recurrent future events.

[Sertraline-induced chronic eosinophilic pneumonia]

INTRODUCTION

Sertraline is a selective serotonin reuptake inhibitor which is often used as first-line treatment for depression. Several patterns of interstitial lung disease attributable to sertraline have been reported in the literature.

CASE REPORT

A 69-year-old patient, who had been taking sertraline to treat severe depression for 10 months, presented with a deterioration in his general condition and respiratory symptoms found to be associated with bilateral pneumonitis. An exhaustive assessment did not reveal any infectious or autoimmune aetiology. Transthoracic lung biopsy revealed a pattern of eosinophilic lung disease. Sertraline-induced lung toxicity was then suspected and this treatment was therefore stopped. The patient's symptoms resolved and the chest imaging normalized.

CONCLUSIONS

Our observation suggests that sertraline was the cause of chronic eosinophilic pneumonia characterized by an insidious clinical presentation several months after starting the medication. Given its widespread prescription, we encourage any clinician facing this disease to pay attention to possible drug-induced origins of lung disease.

Frequency and predictors of cholesterol target attainment in patients with stable coronary heart disease in Belgium: results from the Dyslipidemia International Study II (DYSIS II CHD)

Objectives: To document the frequency and predictors of low-density lipoprotein cholesterol (LDL-C) target value attainment among patients with coronary heart disease (CHD) in Belgium. Methods: The second Dyslipidemia International Study (DYSIS II) was an observational study of the prevalence of dyslipidemias and lipid target value attainment. Patients in this analysis were aged ≥ 18, had documented CHD, and had a full lipid profile. Use of lipid-lowering therapy (LLT), lipid profile, and LDL-C target value attainment (< 70 mg/dL) were assessed cross-sectionally at the enrollment visit. The distribution of LLTs was assessed among treated patients. Multivariate logistic regression was used to identify variables predictive of LDL-C target value attainment in treated patients. Results: We identified 409 patients with CHD in Belgium, 387 (94.6%) of whom were on LLT at the time of the lipid profile. Among treated patients, the rate of LDL-C target value attainment was 40.6%, and statin monotherapy was the most commonly used LLT (79.3%). Among users of statin monotherapy or combination therapy, simvastatin was the most commonly used treatment (41.6% of patients). Diabetes was associated with higher odds of LDL-C target value attainment (OR 2.29, 95% CI 1.33-3.93), and female gender was associated with lower odds (OR 0.48, 95% CI 0.24-0.97). Conclusion: Rates of LDL-C target value attainment are low in patients with CHD in Belgium. Intensifying statin therapy or combining it with non-statins is essential in Belgian patients for optimal LDL-C reduction.

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.

Lipid-lowering nutraceuticals in clinical practice: position paper from an International Lipid Expert Panel

In recent years, there has been growing interest in the possible use of nutraceuticals to improve and optimize dyslipidemia control and therapy. Based on the data from available studies, nutraceuticals might help patients obtain theraputic lipid goals and reduce cardiovascular residual risk. Some nutraceuticals have essential lipid-lowering properties confirmed in studies; some might also have possible positive effects on nonlipid cardiovascular risk factors and have been shown to improve early markers of vascular health such as endothelial function and pulse wave velocity. However, the clinical evidence supporting the use of a single lipid-lowering nutraceutical or a combination of them is largely variable and, for many of the nutraceuticals, the evidence is very limited and, therefore, often debatable. The purpose of this position paper is to provide consensus-based recommendations for the optimal use of lipid-lowering nutraceuticals to manage dyslipidemia in patients who are still not on statin therapy, patients who are on statin or combination therapy but have not achieved lipid goals, and patients with statin intolerance. This statement is intended for physicians and other healthcare professionals engaged in the diagnosis and management of patients with lipid disorders, especially in the primary care setting.

Pooled Safety Analysis of Evolocumab in Over 6000 Patients From Double-Blind and Open-Label Extension Studies

Background:

Evolocumab, a fully human monoclonal antibody to PCSK9 (proprotein convertase subtilisin/kexin type 9), markedly reduces low-density lipoprotein cholesterol across diverse patient populations. The objective of this study was to assess the safety and tolerability of evolocumab in a pooled safety analysis from phase 2 or 3 randomized and placebo or comparator-controlled trials (integrated parent trials) and the first year of open-label extension (OLE) trials that included a standard-of-care control group.

Methods:

This analysis included adverse event (AE) data from 6026 patients in 12 phase 2 and 3 parent trials, with a median exposure of 2.8 months, and, of those patients, from 4465 patients who continued with a median follow-up of 11.1 months in 2 OLE trials. AEs were analyzed separately for the parent and OLE trials. Overall AE rates, serious AEs, laboratory assessments, and AEs of interest were evaluated.

Results:

Overall AE rates were similar between evolocumab and control in the parent trials (51.1% versus 49.6%) and in year 1 of OLE trials (70.0% versus 66.0%), as were those for serious AEs. Elevations of serum transaminases, bilirubin, and creatine kinase were infrequent and similar between groups. Muscle-related AEs were similar between evolocumab and control. Neurocognitive AEs were infrequent and balanced during the double-blind parent studies (5 events [0.1%], evolocumab groups versus 6 events [0.3%], control groups). In the OLE trials, 27 patients (0.9%) in the evolocumab groups and 5 patients (0.3%) in the control groups reported neurocognitive AEs. No neutralizing antievolocumab antibodies were detected.

Conclusions:

Overall, this integrated safety analysis of 6026 patients pooled across phase 2/3 trials and 4465 patients who continued in OLE trials for 1 year supports a favorable benefit-risk profile for evolocumab.

Screening for Small Molecule Inhibitors of Statin-Induced APP C-terminal Toxic Fragment Production

Alzheimer's disease (AD) is characterized by neuronal and synaptic loss. One process that could contribute to this loss is the intracellular caspase cleavage of the amyloid precursor protein (APP) resulting in release of the toxic C-terminal 31-amino acid peptide APP-C31 along with the production of APPΔC31, full-length APP minus the C-terminal 31 amino acids. We previously found that a mutation in APP that prevents this caspase cleavage ameliorated synaptic loss and cognitive impairment in a murine AD model. Thus, inhibition of this cleavage is a reasonable target for new therapeutic development. In order to identify small molecules that inhibit the generation of APP-C31, we first used an APPΔC31 cleavage site-specific antibody to develop an AlphaLISA to screen several chemical compound libraries for the level of N-terminal fragment production. This antibody was also used to develop an ELISA for validation studies. In both high throughput screening (HTS) and validation testing, the ability of compounds to inhibit simvastatin- (HTS) or cerivastatin- (validation studies) induced caspase cleavage at the APP-D720 cleavage site was determined in Chinese hamster ovary (CHO) cells stably transfected with wildtype (wt) human APP (CHO-7W). Several compounds, as well as control pan-caspase inhibitor Q-VD-OPh, inhibited APPΔC31 production (measured fragment) and rescued cell death in a dose-dependent manner. The effective compounds fell into several classes including SERCA inhibitors, inhibitors of Wnt signaling, and calcium channel antagonists. Further studies are underway to evaluate the efficacy of lead compounds - identified here using cells and tissues expressing wt human APP - in mouse models of AD expressing mutated human APP, as well as to identify additional compounds and determine the mechanisms by which they exert their effects.

One-year and longer dual antiplatelet therapy after an acute coronary syndrome: a Belgian position paper

Acute coronary syndrome patients receive DAPT up to one year after their initial event. Exceptions to the guideline-recommended one-year rule, however, are not uncommon. The reasoning behind shorter treatments, such as unacceptable bleeding risk or urgent surgery, should be well documented in the patient's charts and discharge letter. Based on recent evidence, patients at high risk for repetitive events should continue on low-dose ticagrelor without a significant interruption at one year and indefinitely in the absence of excess bleeding risk. As there is currently no reimbursement, policy makers and insurers should be made aware of the continuing risk and unmet clinical need in this patient population. Nevertheless, many unsolved questions need to be answered, both through additional analyses from recent trials such as PEGASUS-TIMI 54 or DAPT, as well as new carefully designed clinical studies.

Pooling and expanding registries of familial hypercholesterolaemia to assess gaps in care and improve disease management and outcomes: Rationale and design of the global EAS Familial Hypercholesterolaemia Studies Collaboration

BACKGROUND

The potential for global collaborations to better inform public health policy regarding major non-communicable diseases has been successfully demonstrated by several large-scale international consortia. However, the true public health impact of familial hypercholesterolaemia (FH), a common genetic disorder associated with premature cardiovascular disease, is yet to be reliably ascertained using similar approaches. The European Atherosclerosis Society FH Studies Collaboration (EAS FHSC) is a new initiative of international stakeholders which will help establish a global FH registry to generate large-scale, robust data on the burden of FH worldwide.

METHODS

The EAS FHSC will maximise the potential exploitation of currently available and future FH data (retrospective and prospective) by bringing together regional/national/international data sources with access to individuals with a clinical and/or genetic diagnosis of heterozygous or homozygous FH. A novel bespoke electronic platform and FH Data Warehouse will be developed to allow secure data sharing, validation, cleaning, pooling, harmonisation and analysis irrespective of the source or format. Standard statistical procedures will allow us to investigate cross-sectional associations, patterns of real-world practice, trends over time, and analyse risk and outcomes (e.g. cardiovascular outcomes, all-cause death), accounting for potential confounders and subgroup effects.

CONCLUSIONS

The EAS FHSC represents an excellent opportunity to integrate individual efforts across the world to tackle the global burden of FH. The information garnered from the registry will help reduce gaps in knowledge, inform best practices, assist in clinical trials design, support clinical guidelines and policies development, and ultimately improve the care of FH patients.

Paradoxical effect of TrkA inhibition in Alzheimer's disease models

An unbiased screen for compounds that block amyloid-β protein precursor (AβPP) caspase cleavage identified ADDN-1351, which reduced AβPP-C31 by 90%. Target identification studies showed that ADDN-1351 is a TrkA inhibitor, and, in complementary studies, TrkA overexpression increased AβPP-C31 and cell death. TrkA was shown to interact with AβPP and suppress AβPP-mediated transcriptional activation. Moreover, treatment of PDAPP transgenic mice with the known TrkA inhibitor GW441756 increased sAβPPα and the sAβPPα to Aβ ratio. These results suggest TrkA inhibition-rather than NGF activation-as a novel therapeutic approach, and raise the possibility that such an approach may counteract the hyperactive signaling resulting from the accumulation of active NGF-TrkA complexes due to reduced retrograde transport. The results also suggest that one component of an optimal therapy for Alzheimer's disease may be a TrkA inhibitor.

Dietary supplementation contributes to lifestyle improvement in hypercholesterolemic patients in real-life contexts

AIMS

Assess the evolution of cardiovascular lifestyle behaviors in hypercholesterolemic patients concomitantly with changes in their daily intake of phytosterol-supplemented yoghurt (Phyto-SY).

METHODS

Nationwide prospective observational study conducted in general practices across France and Spain. Each practitioner suggested lifestyle changes to five consecutive patients with hypercholesterolemia (whether or not they were taking hypocholesterolemic drugs) and recommended daily consumption of Phyto-SY. The study design involved an inclusion visit, a patient's self-monitoring assessment after 1 month, and a final visit after 4 months. Primary evaluation criterion: changes in dietary habits assessed by a standardized Nutritional Lifestyle score. Secondary criteria: changes in lipid profile, anthropometry (waist circumference) and lifestyle behavior.

RESULTS

A total of 2376 hypercholesterolemic patients (of whom 54.8% were women) were included. The average age was 56.2 years old. The Nutritional Lifestyle score improved from 15.4 ± 5.4 to 8.7 ± 4.0 (p < 0.0001). Total cholesterol decreased by 10.6% (<0.0001), HDL-C increased by 8.0% (<0.0001), and LDL-C fell by 12.7% (<0.0001). Similar results were observed in patients treated with statins and those who were not. Frequency of walking (>30 min) increased from 59.3% to 78.3% (p < 0.0001). The overweight rate decreased from 22.8% to 17.5% (p < 0.0001) and waist circumference from 94.6 ± 13.3 cm to 93.0 ± 12.8 cm (p < 0.0001). Nutritional Lifestyles and other lifestyle markers' improvement were parallel to adherence to Phyto-SY adherence.

CONCLUSION

Improvements in Nutritional Lifestyle scores, which included regular consumption of Phyto-SY over 4 months, was significantly linked to healthier lifestyles and to beneficial modifications in atherogenic lipid profiles, which reflected patient empowerment in a 'real life' context.

AβPP-selective BACE inhibitors (ASBI): novel class of therapeutic agents for alzheimer's disease

A systematic approach was used to identify AβPP-selective BACE inhibitors (ASBI) and to evaluate their in vivo ability to modulate AβPP processing selectively. We identified a bioflavonoid nutritional supplement as a molecular lead that acts as an ASBI in cell models, and show that increasing brain levels of this bioflavonoid through a pro-drug approach leads to reduction of Aβ42 in an Alzheimer's disease mouse model. ASBIs represent a novel class of candidate therapeutic agents for Alzheimer's disease.

The multi-functional drug tropisetron binds APP and normalizes cognition in a murine Alzheimer's model

Tropisetron was identified in a screen for candidates that increase the ratio of the trophic, neurite-extending peptide sAPPα to the anti-trophic, neurite-retractive peptide Aβ, thus reversing this imbalance in Alzheimer's disease (AD). We describe here a hierarchical screening approach to identify such drug candidates, moving from cell lines to primary mouse hippocampal neuronal cultures to in vivo studies. By screening a clinical compound library in the primary assay using CHO-7W cells stably transfected with human APPwt, we identified tropisetron as a candidate that consistently increased sAPPα. Secondary assay testing in neuronal cultures from J20 (PDAPP, huAPP(Swe/Ind)) mice showed that tropisetron consistently increased the sAPPα/Aβ 1-42 ratio. In in vivo studies in J20 mice, tropisetron improved the sAPPα/Aβ ratio along with spatial and working memory in mice, and was effective both during the symptomatic, pre-plaque phase (5-6 months) and in the late plaque phase (14 months). This ameliorative effect occurred at a dose of 0.5mg/kg/d (mkd), translating to a human-equivalent dose of 5mg/day, the current dose for treatment of postoperative nausea and vomiting (PONV). Although tropisetron is a 5-HT3 receptor antagonist and an α7nAChR partial agonist, we found that it also binds to the ectodomain of APP. Direct comparison of tropisetron to the current AD therapeutics memantine (Namenda) and donepezil (Aricept), using similar doses for each, revealed that tropisetron induced greater improvements in memory and the sAPPα/Aβ1-42 ratio. The improvements observed with tropisetron in the J20 AD mouse model, and its known safety profile, suggest that it may be suitable for transition to human trials as a candidate therapeutic for mild cognitive impairment (MCI) and AD, and therefore it has been approved for testing in clinical trials beginning in 2014.

Ayurvedic medicinal plants for Alzheimer's disease: a review

Alzheimer's disease is an age-associated, irreversible, progressive neurodegenerative disease that is characterized by severe memory loss, unusual behavior, personality changes, and a decline in cognitive function. No cure for Alzheimer's exists, and the drugs currently available to treat the disease have limited effectiveness. It is believed that therapeutic intervention that could postpone the onset or progression of Alzheimer's disease would dramatically reduce the number of cases in the next 50 years. Ayurvedic medicinal plants have been the single most productive source of leads for the development of drugs, and over a hundred new products are already in clinical development. Indeed, several scientific studies have described the use of various Ayurvedic medicinal plants and their constituents for treatment of Alzheimer's disease. Although the exact mechanism of their action is still not clear, phytochemical studies of the different parts of the plants have shown the presence of many valuable compounds, such as lignans, flavonoids, tannins, polyphenols, triterpenes, sterols, and alkaloids, that show a wide spectrum of pharmacological activities, including anti-inflammatory, anti-amyloidogenic, anti-cholinesterase, hypolipidemic, and antioxidant effects. This review gathers research on various medicinal plants that have shown promise in reversing the Alzheimer's disease pathology. The report summarizes information concerning the phytochemistry, biological, and cellular activities and clinical applications of these various plants in order to provide sufficient baseline information that could be used in drug discovery campaigns and development process, thereby providing new functional leads for Alzheimer's disease.

Altering APP proteolysis: increasing sAPPalpha production by targeting dimerization of the APP ectodomain

One of the events associated with Alzheimer's disease is the dysregulation of α- versus β-cleavage of the amyloid precursor protein (APP). The product of α-cleavage (sAPPα) has neuroprotective properties, while Aβ1-42 peptide, a product of β-cleavage, is neurotoxic. Dimerization of APP has been shown to influence the relative rate of α- and β- cleavage of APP. Thus finding compounds that interfere with dimerization of the APP ectodomain and increase the α-cleavage of APP could lead to the development of new therapies for Alzheimer's disease. Examining the intrinsic fluorescence of a fragment of the ectodomain of APP, which dimerizes through the E2 and Aβ-cognate domains, revealed significant changes in the fluorescence of the fragment upon binding of Aβ oligomers--which bind to dimers of the ectodomain--and Aβ fragments--which destabilize dimers of the ectodomain. This technique was extended to show that RERMS-containing peptides (APP(695) 328-332), disulfiram, and sulfiram also inhibit dimerization of the ectodomain fragment. This activity was confirmed with small angle x-ray scattering. Analysis of the activity of disulfiram and sulfiram in an AlphaLISA assay indicated that both compounds significantly enhance the production of sAPPα by 7W-CHO and B103 neuroblastoma cells. These observations demonstrate that there is a class of compounds that modulates the conformation of the APP ectodomain and influences the ratio of α- to β-cleavage of APP. These compounds provide a rationale for the development of a new class of therapeutics for Alzheimer's disease.

Induction of the C-terminal proteolytic cleavage of AβPP by statins

Statins are drugs commonly used to inhibit cholesterol synthesis, with the goal of reducing vascular diseases such as myocardial infarction and stroke. Statins have also been suggested as a therapeutic option for Alzheimer's disease (AD), although their benefit in AD remains controversial. We have previously shown that the intracellular C-terminal cleavage of the amyloid-β protein precursor (AβPP) is a major contributor to the neuronal toxicity seen in AD, and that this cleavage can be induced by amyloid-β. We now report that certain brain permeable statins are also able to induce the C-terminal cleavage of AβPP and associated cell death, whereas other statins do not. This statin effect on AβPP exceeded the effects of all other FDA-approved drugs in a library composed of these compounds, suggesting that this effect on AβPP cleavage is unique to a subset of the statins. Furthermore, the greatest effect occurred with cerivastatin, which has previously been shown to be the statin associated with the greatest risk of rhabdomyolysis. These results may have implications for the choice of which statins to evaluate in AD therapeutic trials; furthermore, the results may inform statin choice in individuals who are at high risk for the development of AD, such as those with an apolipoprotein E ε4 allele.

Mitochondrial production of reactive oxygen species and incidence of age-associated lymphoma in OF1 mice: Effect of alternate-day fasting

There is currently of a great interest investigating the role of nutrition in the prevention of age-associated disorders. The present study aimed to evaluate, on a particular strain of mice, the efficacy of alternate-day fasting on the mitochondrial production of free radical species and on the incidence of a specific cancer (lymphoma) in aged mice. Alternate fasting, that was initiated in middle age mice through a 4 month period, reduced significantly the incidence of lymphoma (0% versus 33% for controls). No remarkable difference was observed in the overall food consumption between alternate-fed (AF) and ad libitum (AL) mice, suggesting that the efficacy of alternate fasting did not really depend on calorie restriction. A significant decrease in the mitochondrial generation of reactive oxygen species (ROS) that was associated with a significant increase in spleen mitochondria SOD activity was observed when mice were maintained on intermittent fasting. Our results suggest that alternate fasting could exert a beneficial antioxidant effect and a modulation of the oxidative stress associated with aging.

Sequencing of the coding exons of the LRP1 and LDLR genes on individual DNA samples reveals novel mutations in both genes

Five coding polymorphisms in de LRP1 gene, i.e. A217V, A775P, D2080N, D2632E and G4379S were discovered by sequencing its 89 exons in three test-groups of 22 healthy individuals, 29 Alzheimer patients and 18 individuals with different clinical and molecularly uncharacterized lipid metabolism problems. No genetic defect was evident in the LRP1 gene of any of the Alzheimer's disease (AD) patients, further excluding LRP1 as a major genetic problem in AD. Lipoprotein receptor related protein (LRP) A217V (exon 6) was clearly present in all groups as a polymorphism, while D2632E was observed only once in a healthy volunteer. On the other hand, LRP1 alleles A775P, D2080N, and G4379 were encountered only in patients with FH or with undefined problems of lipid metabolism. This finding forced one to also analyze the LDL receptor (LDLR) gene, for which a method was devised to sequence the entire region comprising LDLR exons 2-18. The resulting sequence contig of 33567 nucleotides yielded finally an exact physical map that corrects published and listed LDLR gene maps in many positions. In addition, next to known mutations in LDLR that cause FH, four novel LDLR defects were defined, i.e. del e7-10, exon 9 mutation N407T, a 20 bp insertion in exon 4, and a double mutation C292W/K290R in exon 6. No evidence for pathology connected to the LRP1 'mutations' was obtained by subsequent screening for the five LRP1 variants in larger groups of 110 FH patients and 118 patients with molecularly undefined, clinical problems of cholesterol and/or lipid metabolism. In three individuals with a mutant LDLR gene a variant LRP1 allele was also present, but without direct, obvious clinical compound effects, indicating that the variant LRP1 alleles must, for the present, be considered polymorphisms.

LDL oxidation: therapeutic perspectives

The peroxidation step of lipid transormation is considered to be essential in the pathogenesis of atherosclerosis. Although data concerning the mechanisms by which lipid peroxidation occurs in vivo are scarce, several lines of evidence suggest that some endogenous and exogenous compounds with antioxidant activity could have some beneficial effects in the prevention of atherosclerosis. Ascorbic acid (vitamin C) and alpha-tocopherol (vitamin E) act as the most important hydrophilic and lipophilic antioxidants, respectively in vivo. Accordingly, animal and human studies suggest that these compounds may have some preventive effect against the development of clinical coronary heart disease. Many plant phenols and flavonoids may be important dietary antioxidants and it has been speculated that these compounds in red wine or in the Mediterranean diet could explain the 'French paradox'. Several studies show that antioxidants such as probucol and butylated hydroxytoluene can inhibit development of atherosclerotic lesions in Watanabe and cholesterol-fed rabbits. Some drugs such as beta-blockers, calcium antagonists, hypolipodemic drugs,...appear to have at least in vitro antioxidant effects but the clinical relevance of these properties remains unkonwn. Moreover, some interventions aimed to decrease the LDL-oxidative susceptibility have not been shown to attenuate atherogenesis when cholesterol levels remain markedly elevated.

LDLR Database (second edition): new additions to the database and the software, and results of the first molecular analysis

Mutations in the LDL receptor gene (LDLR) cause familial hypercholesterolemia (FH), a common autosomal dominant disorder. The LDLR database is a computerized tool that has been developed to provide tools to analyse the numerous mutations that have been identified in the LDLR gene. The second version of the LDLR database contains 140 new entries and the software has been modified to accommodate four new routines. The analysis of the updated data (350 mutations) gives the following informations: (i) 63% of the mutations are missense, and only 20% occur in CpG dinucleotides; (ii) although the mutations are widely distributed throughout the gene, there is an excess of mutations in exons 4 and 9, and a deficit in exons 13 and 15; (iii) the analysis of the distribution of mutations located within the ligand-binding domain shows that 74% of the mutations in this domain affect a conserved amino-acid, and that they are mostly confined in the C-terminal region of the repeats. Conversely, the same analysis in the EGF-like domain shows that 64% of the mutations in this domain affect a non-conserved amino-acid, and, that they are mostly confined in the N-terminal half of the repeats. The database is now accessible on the World Wide Web at http://www.umd.necker.fr

High prevalence of a novel mutation in the exon 4 of the low-density lipoprotein receptor gene causing familial hypercholesterolemia in Belgium

In a cohort of 70 unrelated patients living in Southern Belgium with autosomal dominantly inherited hypercholesterolemia, 11 had a hitherto undescribed mutation in exon 4. It consisted in a C-->A mutation at nucleotide 366, resulting in a stop codon at residue Cys122. This C122X mutation is expected to cause a class I receptor defect. The biochemical and clinical data collected from the patients carrying the mutation were consistent with a severe form of familial hypercholesterolemia (FH). Some differences between generations were noted. Amongst the C122X carriers, those born after 1926 had cardiovascular complications earlier than those born before 1926. This raises the possibility that changes in environmental factors during the course of the century have had an unfavorable impact on the prognosis of the disease. The mutation was found in 16% of the suspected FH patients and less frequently (less than 3% of suspected FH) in Northern Belgium. The haplotype of the chromosomes carrying the mutation was the same in all C122X families, but extensive genealogical studies failed to reveal a common ancestor. We conclude that C122X is an old and common cause of FH in Belgium. Screening for this mutation may be useful in the diagnosis of FH in Belgium.

An improved method for detection of low density lipoprotein receptor defects in human T lymphocytes

Familial hypercholesterolemia (FH) results from an inherited functional defect of the low density lipoprotein (LDL) receptor and is complicated by premature atherosclerosis. FH diagnosis is obtained by sophisticated techniques or is suggested by clinical criteria. We have developed a technique based on flow cytometry for the measurement of DiI-labeled LDL uptake in human peripheral blood T lymphocytes left for 2 days in a lipoprotein-deficient culture medium. Flow cytometry allowed us to discriminate the uptake of DiI-LDL by T lymphocytes subpopulation from the uptake by the whole mononuclear population using a T cell-specific anti-CD3 antibody. The method appeared to be highly specific for the receptor-mediated pathway of LDL uptake as DiI-LDL uptake was inhibited in the presence of a 10-fold excess of unlabeled LDL and by EDTA. A good relationship was found between the uptake of DiI-LDL and 125I-labeled LDL degradation. The test was applied in three groups of patients: patients with normal cholesterol levels, patients with heterozygous FH, and patients with high cholesterol levels but without clinical criteria of FH. The mean fluorescence intensities were 23.1 +/- 8.9, 6.3 +/- 1.7, and 17.1 +/- 3.5 (mean +/- standard deviation), respectively. The ability to measure the fluorescence in T lymphocytes improved the discrimination between FH and non-FH subjects when compared with values obtained from the whole mononuclear cell population. These results suggest that our method could be useful for LDL receptor defects screening.

Hypoxic hepatitis in patients with cardiac failure: incidence in a coronary care unit and measurement of hepatic blood flow

The incidence of hypoxic hepatitis was prospectively studied for 1 year in a group of high-risk patients suffering from low cardiac output in a coronary care unit. Hypoxic hepatitis, defined as an increase in serum aminotransferase activity of at least 20 times the upper limit of normal without any other cause for hepatic necrosis, was observed in 20 patients. This represents 2.6% of the 766 patients admitted to the unit during this period and 21.9% of the 91 patients suffering from low cardiac output. Clinical, biological and hemodynamic data were compared between 20 patients with low cardiac output and hypoxic hepatitis, and 48 patients with low cardiac output but without hypoxic hepatitis who survived more than 24 h. In these two groups of patients, hepatic blood flow was measured by galactose clearance at low concentration. Patients with hypoxic hepatitis exhibited a higher central venous pressure (90% versus 38%-p < 0.001) as well as a lower hepatic blood flow (867 +/- 377 ml/min versus 1429 +/- 644 ml/min-p = 0.001). In conclusion, although it is considered a rare hepatic disorder, hypoxic hepatitis is frequent in patients with low cardiac output admitted to the coronary care unit, and is associated with a decrease in hepatic blood flow and passive hepatic venous congestion.

Insulin stimulates receptor-mediated uptake of apoE-enriched lipoproteins and activated alpha 2-macroglobulin in adipocytes

The low density lipoprotein receptor-related protein (LRP) is a cell surface receptor that binds and internalizes several macromolecules including apolipoprotein E-enriched remnant lipoproteins and protease/antiprotease complexes such as activated alpha 2-macroglobulin. Its function has been studied primarily in cultured fibroblasts and in liver. In the current studies, we provide evidence that LRP is present on the surface of primary adipocytes isolated from rat epididymal fat pads. The activity of the receptor increases 2-3-fold within minutes after the adipocytes are exposed to physiological concentrations of insulin as indicated by an increase in the uptake of 125I-labeled activated alpha 2-macroglobulin. There is a corresponding increase in the uptake of [3H]cholesteryl esters from radiolabeled apoE-enriched beta-very low density lipoprotein. The latter uptake was inhibited by an antibody against LRP and by a fusion protein containing the 39-kDa protein, also called receptor-associated protein, a known inhibitor of LRP function. In vivo, rats that had been fed ad libitum accumulated approximately 24-fold more chylomicron cholesteryl esters in their epididymal fat pads than did fasted control animals. We suggest that insulin stimulation of LRP, in a synergistic action with lipoprotein lipase, increases the endocytic uptake of cholesteryl esters and triglycerides from remnant lipoproteins in postprandial adipocytes.

Coronary artery spasm induced by 5-fluorouracil

We report a case of coronary artery spasm induced by 5-fluorouracil. The symptoms occurred during continuous intravenous infusion of the drug, and a coronary spasm was visualized at angiography.