Naturally Occurring PCSK9 Inhibitors

Genetic, epidemiological and pharmacological data have led to the conclusion that antagonizing or inhibiting Proprotein convertase subtilisin/kexin type 9 (PCSK9) reduces cardiovascular events. This clinical outcome is mainly related to the pivotal role of PCSK9 in controlling low-density lipoprotein (LDL) cholesterol levels. The absence of oral and affordable anti-PCSK9 medications has limited the beneficial effects of this new therapeutic option. A possible breakthrough in this field may come from the discovery of new naturally occurring PCSK9 inhibitors as a starting point for the development of oral, small molecules, to be used in combination with statins in order to increase the percentage of patients reaching their LDL-cholesterol target levels. In the present review, we have summarized the current knowledge on natural compounds or extracts that have shown an inhibitory effect on PCSK9, either in experimental or clinical settings. When available, the pharmacodynamic and pharmacokinetic profiles of the listed compounds are described

Pharmacological aspects of ANGPTL3 and ANGPTL4 inhibitors: new therapeutic approaches for the treatment of atherogenic dyslipidemia

Among the determinants of atherosclerotic cardiovascular disease (ASCVD), genetic and experimental evidence has provided data on a major role of angiopoietin-like proteins 3 and 4 (ANGPTL3 and ANGPTL4) in regulating the activity of lipoprotein lipase (LPL), antagonizing the hydrolysis of triglycerides (TG). Indeed, beyond low-density lipoprotein cholesterol (LDL-C), ASCVD risk is also dependent on a cluster of metabolic abnormalities characterized by elevated fasting and post-prandial levels of TG-rich lipoproteins and their remnants. In a head-to-head comparison between murine models for ANGPTL3 and ANGPTL4, the former was found to be a better pharmacological target for the treatment of hypertriglyceridemia. In humans, loss-of-function mutations of ANGPTL3 are associated with a marked reduction of plasma levels of VLDL, low-density lipoprotein (LDL) and high-density lipoprotein (HDL). Carriers of loss-of-function mutations of ANGPTL4 show instead lower TG-rich lipoproteins and a modest but significant increase of HDL. The relevance of ANGPTL3 and ANGPTL4 as new therapeutic targets is proven by the development of monoclonal antibodies or antisense oligonucleotides. Studies in animal models, including non-human primates, have demonstrated that short-term treatment with monoclonal antibodies against ANGPTL3 and ANGPTL4 induces activation of LPL and a marked reduction of plasma TG-rich-lipoproteins, apparently without any major side effects. Inhibition of both targets also partially reduces LDL-C, independent of the LDL receptor. Similar evidence has been observed with the antisense oligonucleotide ANGPTL3-LRX. The genetic studies have paved the way for the development of new ANGPTL3 and 4 antagonists for the treatment of atherogenic dyslipidemias. Conclusive data of phase 2 and 3 clinical trials are still needed in order to define their safety and efficacy profile

Proprotein Convertase Subtilisin/Kexin Type 9, Brain Cholesterol Homeostasis and Potential Implication for Alzheimer’s Disease

Alzheimer’s disease (AD) has been associated with dysregulation of brain cholesterol homeostasis. Proprotein convertase subtilisin/kexin type 9 (PCSK9), beyond the known role in the regulation of plasma low-density lipoprotein cholesterol, was first identified in the brain with a potential involvement in brain development and apoptosis. However, its role in the central nervous system (CNS) and in AD pathogenesis is still far from being understood. While in vitro and in vivo evidence led to controversial results, genetic studies apparently did not find an association between PCSK9 loss of function mutations and AD risk or prevalence. In addition, a potential impairment of cognitive performances by the treatment with the PCSK9 inhibitors, alirocumab and evolocumab, have been excluded, although ongoing studies with longer follow-up will provide further insights. PCSK9 is able to affect the expression of neuronal receptors involved in cholesterol homeostasis and neuroinflammation, and higher PCSK9 concentrations have been found in the cerebrospinal fluid (CSF) of AD patients. In this review article, we critically examined the science of PCSK9 with respect to its modulatory role of the mechanisms underlying the pathogenesis of AD. In addition, based on literature data, we made the hypothesis to consider brain PCSK9 as a negative modulator of brain cholesterol homeostasis and neuroinflammation and a potential pharmacological target for treatment

COVID-19 Severity in Multiple Sclerosis: Putting Data Into Context

Background and objectives: It is unclear how multiple sclerosis (MS) affects the severity of COVID-19. The aim of this study is to compare COVID-19-related outcomes collected in an Italian cohort of patients with MS with the outcomes expected in the age- and sex-matched Italian population. Methods: Hospitalization, intensive care unit (ICU) admission, and death after COVID-19 diagnosis of 1,362 patients with MS were compared with the age- and sex-matched Italian population in a retrospective observational case-cohort study with population-based control. The observed vs the expected events were compared in the whole MS cohort and in different subgroups (higher risk: Expanded Disability Status Scale [EDSS] score > 3 or at least 1 comorbidity, lower risk: EDSS score ≤ 3 and no comorbidities) by the χ2 test, and the risk excess was quantified by risk ratios (RRs). Results: The risk of severe events was about twice the risk in the age- and sex-matched Italian population: RR = 2.12 for hospitalization (p < 0.001), RR = 2.19 for ICU admission (p < 0.001), and RR = 2.43 for death (p < 0.001). The excess of risk was confined to the higher-risk group (n = 553). In lower-risk patients (n = 809), the rate of events was close to that of the Italian age- and sex-matched population (RR = 1.12 for hospitalization, RR = 1.52 for ICU admission, and RR = 1.19 for death). In the lower-risk group, an increased hospitalization risk was detected in patients on anti-CD20 (RR = 3.03, p = 0.005), whereas a decrease was detected in patients on interferon (0 observed vs 4 expected events, p = 0.04). Discussion: Overall, the MS cohort had a risk of severe events that is twice the risk than the age- and sex-matched Italian population. This excess of risk is mainly explained by the EDSS score and comorbidities, whereas a residual increase of hospitalization risk was observed in patients on anti-CD20 therapies and a decrease in people on interferon

DMTs and Covid-19 severity in MS: a pooled analysis from Italy and France

We evaluated the effect of DMTs on Covid-19 severity in patients with MS, with a pooled-analysis of two large cohorts from Italy and France. The association of baseline characteristics and DMTs with Covid-19 severity was assessed by multivariate ordinal-logistic models and pooled by a fixed-effect meta-analysis. 1066 patients with MS from Italy and 721 from France were included. In the multivariate model, anti-CD20 therapies were significantly associated (OR = 2.05, 95%CI = 1.39–3.02, p < 0.001) with Covid-19 severity, whereas interferon indicated a decreased risk (OR = 0.42, 95%CI = 0.18–0.99, p = 0.047). This pooled-analysis confirms an increased risk of severe Covid-19 in patients on anti-CD20 therapies and supports the protective role of interferon

Nabiximols in Multiple Sclerosis-Related Spasticity

Multiple sclerosis (MS) is a chronic, autoimmune disease caused by inflammation and neurodegeneration, which is associated with a wide spectrum of central nervous system symptoms. Spasticity, defined as abnormally increased muscular tone, is 1 of the most common disabling symptoms in MS, occurring in up to 80% of MS patients and showing increased severity as the disease progresses over time. The approval of nabiximols for the management of MS spasticity opened up a new treatment opportunity to many patients. Here, we report a case of a 43-year-old man with a primary progressive MS diagnosis and spasticity-associated symptoms. Nabiximols had significant benefits with respect to spasticity symptoms

Tribute to Kenneth Snelson

This paper presents the project of a tensegrity pavilion dedicated to the memory of Kenneth Snelson (1927-2016), the American artist who invented tensegrities and popularized them with the sculptures he built worldwide. The shape of the pavilion, based on a combination of X-Modules, is that of a “gate”, so that when walking through it, one can observe on the sides and above the transparent “floating-compression” arrangement of struts and cables. The choice of materials employed in the construction – bars in fir-wood for struts and recycled sailing ropes for cables - is also inspired by the Snelson’s tensegrity primary plywood “X-Piece”, complying with a fabrication and assembly procedure conceived to maximize simplicity and recyclability. The form finding of the pavilion was carried out by energy minimization on a virtual elastic structure, while for the structural design, a linearized static and dynamic analysis was performed considering own weight load and live loads. The geometry developed for the nodal connections between struts and cables has been realized by the Italian company Progetto Legno, according to a customized fabrication process

Lipoprotein(a) and PCSK9 inhibition: clinical evidence

Compelling evidence has emerged from epidemiological and Mendelian randomization analyses relative to the causality of lipoprotein(a) [Lp(a)] in atherosclerotic cardiovascular diseases (ASCVD), being elevated Lp(a) a strong risk factor regardless of the reduction of LDL-C achieved by statins. So far, no specific available agent can lower Lp(a) to the extent required to achieve a cardiovascular (CV) benefit, i.e. approximately 100mg/dL. The most recent outcomes trial FOURIER with evolocumab showed that a 25nmol/L (12mg/dL) reduction in Lp(a) corresponded to a 15% decrement in the relative risk of cardiovascular disease. The ODYSSEY OUTCOMES trial with alirocumab has been the first demonstrating that a reduction in Lp(a) associates with less major adverse cardiovascular events (MACE), i.e. hazard ratio: 0.994 per 1mg/dL decrement in Lp(a). The Lp(a) lowering effect driven by PCSK9 inhibition was confirmed in carriers of PCSK9 loss-of-function mutations in which Lp(a) and oxPL-apoB levels were decreased compared to non-carriers as was for a slight larger number of apo(a) Kringle IV repeats. Although PCSK9 inhibitors are not able to decrease Lp(a) to the extent required to achieve a CV benefit, their use has led to a higher discontinuation rate in lipoprotein apheresis in patients with progressive ASCVD and high plasma Lp(a)