ANGPTL3 and ApoC-III inhibitors for treating hypertriglyceridemia in context: horses for courses?

PURPOSE OF REVIEW: Hypertriglyceridemia (HTG) is an independent and casual risk factor for atherosclerotic cardiovascular disease (ASCVD). There is an unmet need for more effective treatments for patients with HTG. Angiopoietin-like protein 3 (ANGPTL3) and apolipoprotein C-III (apoC-III) are key regulators of triglyceride-rich lipoprotein (TRL) metabolism. We review recent clinical trials targeting ANGPTL3 and apoC-III with monoclonal antibody and nucleic acid therapies, including antisense oligonucleotides and small interfering RNA. RECENT FINDINGS: ANGPTL3 and apoC-III inhibitors are effective in lowering plasma triglycerides and TRLs, with possibly greater efficacy with the inhibition of apoC-III. By contrast to ANGPTL3 inhibition that has the advantage of greater lowering of plasma low-density lipoprotein (LDL)-cholesterol and apoB levels, apoC-III inhibition only has a modest or no effect in lowering plasma LDL-cholesterol and apoB concentrations. Therapeutic inhibition of ANGPTL3 and apoC-III can correct HTG possibly by reducing production and increasing catabolism of TRL particles, but this remains to be formally investigated in patients with HTG. SUMMARY: Novel agents targeting ANGPTL3 and apoC-III can correct HTG and potentially lower risk of ASCVD in patients with HTG. The long-term safety and cost-effectiveness of these agents await confirmation in ongoing and future studies.

An Analysis of the Gut Microbiota and Related Metabolites following PCSK9 Inhibition in Statin-Treated Patients with Elevated Levels of Lipoprotein(a).

BACKGROUND: Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of global mortality, often associated with high blood levels of LDL cholesterol (LDL-c). Medications like statins and PCSK9 inhibitors, are used to manage LDL-c levels and reduce ASCVD risk. Recent findings connect the gut microbiota and its metabolites to ASCVD development. We showed that statins modulate the gut microbiota including the production of microbial metabolites involved in the regulation of cholesterol metabolism such as short chain fatty acids (SCFAs) and bile acids (BAs). Whether this pleiotropic effect of statins is associated with their antimicrobial properties or it is secondary to the modulation of cholesterol metabolism in the host is unknown. In this observational study, we evaluated whether alirocumab, a PCSK9 inhibitor administered subcutaneously, alters the stool-associated microbiota and the profiles of SCFAs and BAs. METHODS: We used stool and plasma collected from patients enrolled in a single-sequence study using alirocumab. Microbial DNA was extracted from stool, and the bacterial component of the gut microbiota profiled following an amplicon sequencing strategy targeting the V3-V4 region of the 16S rRNA gene. Bile acids and SCFAs were profiled and quantified in stool and plasma using mass spectrometry. RESULTS: Treatment with alirocumab did not alter bacterial alpha (Shannon index, p = 0.74) or beta diversity (PERMANOVA, p = 0.89) in feces. Similarly, circulating levels of SCFAs (mean difference (95% confidence interval (CI)), 8.12 [-7.15-23.36] µM, p = 0.25) and BAs (mean difference (95% CI), 0.04 [-0.11-0.19] log10(nmol mg-1 feces), p = 0.56) were equivalent regardless of PCSK9 inhibition. Alirocumab therapy was associated with increased concentration of BAs in feces (mean difference (95% CI), 0.20 [0.05-0.34] log10(nmol mg-1 feces), p = 0.01). CONCLUSION: In statin-treated patients, the use of alirocumab to inhibit PCSK9 leads to elevated levels of fecal BAs without altering the bacterial population of the gut microbiota. The association of alirocumab with increased fecal BA concentration suggests an additional mechanism for the cholesterol-lowering effect of PCSK9 inhibition.

Cascade testing of children and adolescents for elevated Lp(a) in pedigrees with familial hypercholesterolaemia.

Elevated plasma lipoprotein(a) [Lp(a)] is a common, inherited condition independently causing cardiovascular disease. Recent expert recommendations suggest opportunistically testing for elevated Lp(a) during cascade testing for familial hypercholesterolaemia (FH). We investigated the effectiveness of detecting elevated Lp(a) in 103 children and adolescents who were first-degree relatives of 66 adult index FH cases as part of an established FH cascade screening program. The yield of detection of elevated Lp(a) using a threshold of ≥30 mg/dL in children and adolescents was assessed. Cascade testing from FH index cases with elevated Lp(a) ≥50 mg/dL identified 1 case of Lp(a) ≥30 mg/dL for every 2 children or adolescents tested. In contrast, opportunistic screening from index cases with FH but normal Lp(a) levels demonstrated 1 case of Lp(a) ≥30 mg/dL for every 7.5 children or adolescents tested (p < 0.001). In conclusion, cascade testing for elevated Lp(a) from index cases with FH and elevated Lp(a) is effective in identifying new cases of elevated Lp(a).

Adherence to pharmacotherapy: sine qua non for reducing cumulative risk of premature coronary disease in familial hypercholesterolemia.

PURPOSE OF REVIEW: Familial hypercholesterolemia (FH) is a dominant and highly penetrant monogenic disorder present from birth that markedly elevates plasma low-density lipoprotein (LDL)-cholesterol concentration and, if untreated, leads to atherosclerotic cardiovascular disease (ASCVD). The risk of ASCVD can be substantially reduced with lipid-lowering treatment (LLT). However, adherence to LLT remains a major challenge in FH patients and an under-recognized issue. We review several barriers to treatment adherence and implementation strategies for improving adherence in patients with FH. RECENT FINDINGS: Barriers that negatively affect patient adherence to treatment include the misunderstanding of perceived and actual risk of FH and the benefits of LLT, inadequate knowledge, lack of standardization of treatment, insufficient monitoring of LDL-cholesterol level, and inequalities in healthcare resources. Education of patients, carers and healthcare providers, guideline-directed treatment goals, regular monitoring, medication regimen simplification and greater access to established and new drugs are crucial enablers for improving adherence to treatment. However, given FH is present from birth, strategies for life-long adherence from childhood or young adulthood is critically important and requires further study. To be effective, strategies should be multifaceted, targeted and patient-centred involving a multidisciplinary-team with support from family, communities and peer groups. SUMMARY: FH confers a significant risk for ASCVD from a young age. Achieving better medication adherence is foundational for improving clinical outcomes and reducing the burden of atherosclerosis over a lifetime. Identification of key barriers and enablers are critical for implementing better adherence to treatment across the life-course of patients with FH.

Improved arterial inflammation with high dose omega-3 fatty acids in patients with elevated lipoprotein(a): Selective effect of eicosapentaenoic acid?

Elevated lipoprotein(a) [Lp(a)] is a causal risk factor for atherosclerotic cardiovascular disease. However, there are no approved and effective treatments for lowering Lp(a) and the associated cardiovascular risks. Omega-3 fatty acids (ω-3FAs), primarily eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have both triglyceride-lowering and anti-inflammatory properties. This pilot study investigated the effect of high dose ω-3FAs (3.6 g/day) on arterial inflammation in 12 patients with elevated Lp(a) (> 0.5 g/L) and stable coronary artery disease (CAD) receiving cholesterol-lowering treatment. Arterial inflammation was determined using 18F-fluorodexoyglucose positron emission tomography/computed tomography before and after 12-weeks intervention. ω-3FAs significantly lowered plasma concentrations of triglycerides (-17%, p < 0.01), Lp(a) (-5%, p < 0.01) as well as aortic maximum standardized uptake value (SUVmax) (-4%, p < 0.05). The reduction in SUVmax was significantly inversely associated with average on-treatment EPA (r = -0.750, p < 0.01), but not DHA and triglyceride, concentrations. In conclusion, high dose ω-3FAs decrease arterial inflammation in patients with elevated Lp(a) and stable CAD, which may involve a direct arterial effect of EPA.

A multicentre double-blinded randomized controlled trial on the efficacy of laser-assisted hatching in patients with repeated implantation failure undergoing IVF or ICSI.

STUDY QUESTION: Does assisted hatching increase the cumulative live birth rate in subfertile couples with repeated implantation failure? SUMMARY ANSWER: This study showed no evidence of effect for assisted hatching as an add-on in subfertile couples with repeated implantation failure. WHAT IS KNOWN ALREADY: The efficacy of assisted hatching, with regard to the live birth rate has not been convincingly demonstrated in randomized trials nor meta-analyses. It is suggested though that especially poor prognosis women, e.g. women with repeated implantation failure, might benefit most from assisted hatching. STUDY DESIGN, SIZE, DURATION: The study was designed as a double-blinded, multicentre randomized controlled superiority trial. In order to demonstrate a statistically significant absolute increase in live birth rate of 10% after assisted hatching, 294 participants needed to be included per treatment arm, being a total of 588 subfertile couples. Participants were included and randomized from November 2012 until November 2017, 297 were allocated to the assisted hatching arm of the study and 295 to the control arm. Block randomization in blocks of 20 participants was applied and randomization was concealed from participants, treating physicians, and laboratory staff involved in the embryo transfer procedure. Ovarian hyperstimulation, oocyte retrieval, laboratory procedures, embryo selection for transfer and cryopreservation, the transfer itself, and luteal support were performed according to local protocols and were identical in both the intervention and control arm of the study with the exception of the assisted hatching procedure which was only performed in the intervention group. The laboratory staff performing the assisted hatching procedure was not involved in the embryo transfer itself. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were eligible for inclusion in the study after having had either at least two consecutive fresh IVF or ICSI embryo transfers, including the transfer of frozen and thawed embryos originating from those fresh cycles, and which did not result in a pregnancy or as having had at least one fresh IVF or ICSI transfer and at least two frozen embryo transfers with embryos originating from that fresh cycle which did not result in a pregnancy. The study was performed at the laboratory sites of three tertiary referral hospitals and two university medical centres in the Netherlands. MAIN RESULTS AND THE ROLE OF CHANCE: The cumulative live birth rate per started cycle, including the transfer of fresh and subsequent frozen/thawed embryos if applicable, resulted in 77 live births in the assisted hatching group (n = 297, 25.9%) and 68 live births in the control group (n = 295, 23.1%). This proved to be statistically not significantly different (relative risk: 1.125, 95% CI: 0.847 to 1.494, P = 0.416). LIMITATIONS, REASONS FOR CAUTION: There was a small cohort of subfertile couples that after not achieving an ongoing pregnancy, still had cryopreserved embryos in storage at the endpoint of the trial, i.e. 1 year after the last randomization. It cannot be excluded that the future transfer of these frozen/thawed embryos increases the cumulative live birth rate in either or both study arms. Next, at the start of this study, there was no international consensus on the definition of repeated implantation failure. Therefore, it cannot be excluded that assisted hatching might be effective in higher order repeated implantation failures. WIDER IMPLICATIONS OF THE FINDINGS: This study demonstrated no evidence of a statistically significant effect for assisted hatching by increasing live birth rates in subfertile couples with repeated implantation failure, i.e. the couples which, based on meta-analyses, are suggested to benefit most from assisted hatching. It is therefore suggested that assisted hatching should only be offered if information on the absence of evidence of effect is provided, at no extra costs and preferably only in the setting of a clinical trial taking cost-effectiveness into account. STUDY FUNDING/COMPETING INTEREST(S): None. TRIAL REGISTRATION NUMBER: Netherlands Trial Register (NTR 3387, NL 3235, https://www.clinicaltrialregister.nl/nl/trial/26138). TRIAL REGISTRATION DATE: 6 April 2012. DATE OF FIRST PATIENT'S ENROLMENT: 28 November 2012.

The Promise of PCSK9 and Lipoprotein(a) as Targets for Gene Silencing Therapies.

PURPOSE: High plasma concentrations of LDL and lipoprotein(a) (Lp[a]) are independent and causal risk factors for atherosclerotic cardiovascular disease (ASCVD). There is an unmet therapeutic need for high-risk patients with elevated levels of LDL-C and/or Lp(a). Recent advances in the development of nucleic acids for gene silencing (ie, triantennary N-acetylgalactosamine conjugated antisense-oligonucleotides [ASOs] and small interfering RNA [siRNA]) targeting proprotein convertase subtilisin/kexin type 9 (PCSK9) and Lp(a) offer effective and sustainable therapies. METHODS: Related articles in the English language were identified through a search for original and review articles in the PubMed database using the following key terms: cardiovascular disease, dyslipidemia, PCSK9 inhibitors, Lp(a), LDL-cholesterol, familial hypercholesterolemia, siRNA, and antisense oligonucleotide and clinical trials (either alone or in combination). FINDINGS: Inclisiran, the most advanced siRNA-treatment targeting hepatic PCSK9, is well tolerated, producing a >30% reduction on LDL-C levels in randomized controlled trials. Pelacarsen is the most clinical advanced ASO, whereas olpasiran and SLN360 are the 2 siRNAs directed against the mRNA of the LPA gene. Evidence suggests that all Lp(a)-targeting agents are safe and well tolerated, with robust and sustained reduction in plasma Lp(a) concentration up to 70% to 90% in individuals with elevated Lp(a) levels. IMPLICATIONS: Cumulative evidence from clinical trials supports the value of ASO and siRNA therapies targeting the synthesis of PCSK9 and Lp(a) for lowering LDL-C and Lp(a) in patients with established ASCVD or high risk of ASCVD. Further research is needed to examine whether gene silencing therapy could improve clinical outcomes in patients with elevated LDL and/or Lp(a) levels. Confirmation of the tolerability and cost-effectiveness of long-term inhibition of PCSK9 and Lp(a) with this approach is essential.

Effect of omega-3 fatty acid ethyl esters on postprandial arterial elasticity in patients with familial hypercholesterolemia.

BACKGROUND: Impaired arterial elasticity reflects increased risk of atherosclerotic cardiovascular disease in patients with familial hypercholesterolemia (FH). Treatment with omega-3 fatty acid ethyl esters (ω-3FAEEs) in FH patients has been shown to improve postprandial triglyceride-rich lipoprotein (TRL) metabolism, including TRL-apolipoprotein(a) [TRL-apo(a)]. Whether ω-3FAEE intervention also improves postprandial arterial elasticity in FH has not been demonstrated. METHODS: We carried out an 8-week open-label, randomized, crossover trial to test the effect of ω-3FAEEs (4 g/day) on postprandial arterial elasticity in 20 FH subjects following ingestion of an oral fat load. Fasting and postprandial large (C1) and small (C2) artery elasticity at 4 and 6 h were measured by pulse contour analysis of the radial artery. The area under-the-curves (AUCs) (0-6 h) for C1, C2, plasma triglycerides and TRL-apo(a) were determined using the trapezium rule. RESULTS: Compared with no treatment, ω-3FAEEs significantly increased fasting (+9%, P < 0.05) and postprandial C1 at 4 h (+13%, P < 0.05) and at 6 h (+10%, P < 0.05), with improvement in the postprandial C1 AUC (+10%, P < 0.01). ω-3FAEEs also decreased postprandial triglyceride and TRL-apo(a) AUCs (-17% and -19%, respectively, P < 0.05). ω-3FAEEs had no significant effect on fasting and postprandial C2. The change in C1 AUC was inversely associated with the changes in the AUC of triglycerides (r = -0.609, P < 0.01) and TRL-apo(a) (r = -0.490, P < 0.05). CONCLUSIONS: High-dose ω-3FAEEs improves postprandial large artery elasticity in adults with FH. Reduction in postprandial TRL-apo(a) with ω-3FAEEs may contribute to the improvement in large artery elasticity. However, our findings need to be confirmed in a larger population. CLINICAL TRIAL REGISTRATION: https://www. CLINICALTRIALS: com/NCT01577056.

Plasma Amyloid-ß Homeostasis Is Associated with Body Mass Index and Weight Loss in People with Overweight and Obesity.

BACKGROUND: Obesity is linked to a higher incidence of Alzheimer's disease (AD). Studies show that plasma amyloid-ß (Aß) dyshomeostasis, particularly low 42/40 ratio indicates a heightened risk for developing AD. However, the relationship between body mass index (BMI) and circulating plasma Aß has not been extensively studied. OBJECTIVE: We hypothesized that people with a high BMI have altered plasma Aß homeostasis compared with people with a lower BMI. We also tested whether reducing BMI by calorie-restriction could normalize plasma concentrations of Aß. METHODS: Plasma concentrations of Aß40, Aß42, and Aß42/40 ratio were measured in 106 participants with BMIs classified as lean, overweight, or obese. From this cohort, twelve participants with overweight or obese BMIs entered a 12-week calorie-restriction weight loss program. We then tested whether decreasing BMI affected plasma Aß concentrations. RESULTS: Plasma Aß42/40 ratio was 17.54% lower in participants with an obese BMI compared to lean participants (p < 0.0001), and 11.76% lower compared to participants with an overweight BMI (p < 0.0001). The weight loss regimen decreased BMI by an average of 4.02% (p = 0.0005) and was associated with a 6.5% decrease in plasma Aß40 (p = 0.0425). However, weight loss showed negligible correlations with plasma Aß40, Aß42, and Aß42/40 ratio. CONCLUSION: Obesity is associated with aberrant plasma Aß homeostasis which may be associated with an increased risk for AD. Weight loss appears to lower Aß40, but large-scale longitudinal studies in addition to molecular studies are required to elucidate the underlying mechanisms of how obesity and weight loss influence plasma Aß homeostasis.

Is type 2 diabetes associated dementia a microvascular early-Alzheimer's phenotype induced by aberrations in the peripheral metabolism of lipoprotein-amyloid?

There is increasing evidence of a positive association of type 2 diabetes with Alzheimer's disease (AD), the most prevalent form of dementia. Suggested pathways include cerebral vascular dysfunction; central insulin resistance, or exaggerated brain abundance of potentially cytotoxic amyloid-ß (Aß), a hallmark feature of AD. However, contemporary studies find that Aß is secreted in the periphery by lipogenic organs and secreted as nascent triglyceride-rich lipoproteins (TRL's). Pre-clinical models show that exaggerated abundance in blood of TRL-Aß compromises blood-brain barrier (BBB) integrity, resulting in extravasation of the TRL-Aß moiety to brain parenchyme, neurovascular inflammation and neuronal degeneration concomitant with cognitive decline. Inhibiting secretion of TRL-Aß by peripheral lipogenic organs attenuates the early-AD phenotype indicated in animal models, consistent with causality. Poorly controlled type 2 diabetes commonly features hypertriglyceridemia because of exaggerated TRL secretion and reduced rates of catabolism. Alzheimer's in diabetes may therefore be a consequence of heightened abundance in blood of lipoprotein-Aß and accelerated breakdown of the BBB. This review reconciles the prevailing dogma of amyloid associated cytotoxicity as a primary risk factor in late-onset AD, with substantial evidence of a microvascular axis for dementia-in-diabetes. Consideration of potentially relevant pharmacotherapies to treat insulin resistance, dyslipidaemia and by extension plasma amyloidemia in type 2 diabetes are discussed.

Lipoprotein(a) Is Associated with Thrombus Burden in Culprit Arteries of Younger Patients with ST-Segment Elevation Myocardial Infarction.

BACKGROUND: Lipoprotein(a) (Lp[a]) is a risk factor for cardiovascular disease. The burden of thrombus in ST-segment elevation myocardial infarction (STEMI) has implications on treatment and outcomes. However, the association between Lp(a) and atherothrombosis in STEMI remains unclear. OBJECTIVES: The aim of the study was to determine the association between Lp(a) and culprit artery thrombus burden in younger patients with STEMI. METHODS: This was a single-center study of 83 patients aged <65 years with STEMI between 2016-2018 who underwent percutaneous coronary intervention and measurement of Lp(a); those receiving thrombolytic therapy were excluded. Thrombus burden in the culprit artery was determined angiographically using the Thrombolysis In Myocardial Infarction score and classified as absent-to-small, moderate, or large. Elevated Lp(a) was defined as plasma mass concentration >30 mg/dL. Multivariate analysis was performed adjusting for cardiovascular risk factors. RESULTS: The mean age was 48.0 ± 8.4 years, and 78.3% were male. Thirteen (16%), 9 (11%), and 61 (73%) patients had small, moderate, or large thrombus burden, respectively, and 34 (41%) had elevated Lp(a). Elevated Lp(a) was associated with greater thrombus burden compared to normal Lp(a) (large burden 85% vs. 65%; p = 0.024). Elevated Lp(a) was associated with moderate or large thrombus in univariate (OR 10.70 [95% CI 1.32-86.82]; p = 0.026) and multivariate analysis (OR 10.33 [95% CI 1.19-89.52]; p = 0.034). Lp(a) was not associated with culprit artery or stenosis location according to culprit artery. CONCLUSIONS: Elevated Lp(a) is associated with greater thrombus burden in younger patients with STEMI. The finding of this observational study accords with the thrombotic and anti-fibrinolytic properties of Lp(a). A causal relationship requires verification.

Probabilistic risk analysis of unit trains versus manifest trains for transporting hazardous materials.

When transporting hazardous materials by rail, train types (unit train or manifest train) can influence derailment and release risks in several ways. Unit trains only experience risks on mainlines and when arriving at or departing from terminals, while manifest trains experience additional switching risks in yards. A comprehensive risk assessment methodology is needed to quantitively compare shipments with unit trains and manifest trains, considering both mainline and yard operations. To fulfill this research gap, this paper constructs event chains for line-haul risks, arrival/departure risks, and yard switching risks using various probabilistic models and finally determines expected casualties as the consequences of a potential train derailment and release incident. Five illustrative scenarios are designed to analyze the best and worst cases and compare the transportation risk differences between service options using unit trains and manifest trains. The comparison results indicate that placing all tank cars at the positions with the lowest probability of derailing and switching tank cars alone in classification yards could provide the lowest risk estimate given the same transportation demand.

Prospective Randomized Controlled Trial Comparing Laparoscopic Palomo Surgery vs Scrotal Antegrade Sclerotherapy in Adolescent Varicocele.

PURPOSE: Varicocele is a common condition in adolescence and the most common correctable cause of infertility. This study aimed to analyze and compare the outcomes of scrotal antegrade sclerotherapy and laparoscopic Palomo surgery in a tertiary referral center. MATERIALS AND METHODS: Patients with left grade 3 varicocele indicated for surgery were prospectively enrolled and randomly allocated to the scrotal antegrade sclerotherapy and laparoscopic Palomo surgery groups, with their respective contralateral normal testes taken as controls. The primary outcome measures were clinical varicocele recurrence, testicular catch-up growth, and postoperative hydrocele. All patients were evaluated clinically and using Doppler ultrasound by radiologists. RESULTS: From 2015 to 2020, 113 patients completed the study and were statistically analyzed (scrotal antegrade sclerotherapy, n = 57; laparoscopic Palomo surgery, n = 56). All patients had significantly smaller testes preoperatively; the testicular volume differences with control testes were -23% in scrotal antegrade sclerotherapy and -19% in laparoscopic Palomo surgery. At 12-month follow-up, there were no statistically significant differences in clinical recurrences between the 2 groups (scrotal antegrade sclerotherapy = 5.3% vs laparoscopic Palomo surgery = 5.4%, P > .05, noninferiority test). Testicular catch-up growths were observed in both groups; the mean testicular volume difference between the treatment and control testes decreased from -23% to -8.1% in scrotal antegrade sclerotherapy (P < .001) and from -19% to -9.3% in laparoscopic Palomo surgery (P < .001) at 12-month follow-up. There was no postoperative hydrocele in the scrotal antegrade sclerotherapy group compared to 7 cases in the laparoscopic Palomo surgery group (0% vs 13%, P = .006). CONCLUSIONS: Both scrotal antegrade sclerotherapy and laparoscopic Palomo surgery are safe and effective procedures for treatment of adolescent varicocele with significant positive effect on testicular catch-up growth. Scrotal antegrade sclerotherapy is not inferior to laparoscopic Palomo surgery in terms of clinical recurrence rate and has significantly less postoperative hydrocele.