👤 Maurizio R Averna

We aimed to compare the molecular and clinical characteristics of patients identified in Italy as affected by either familial chylomicronemia syndrome (FCS) or multifactorial chylomicronemia syndrome (MCS) and to assess the overall benefit of novel triglyceride-lowering therapies prescribed to these patients within the routine clinical care. From the national LIPIGEN-sHTG (Lipid Transport Disorders Italian Genetic Network-Severe Hypertriglyceridemia) registry, 169 patients (57 FCS, 51 MCS, 61 variant-negative, variant-negative MCS) were retrospectively analyzed. Data on clinical and genetic characteristics, medical history, and medications were collected. Peak triglyceride levels were used to define untreated lipid phenotypes. In FCS, 72% exhibited biallelic As compared with MCS, patients with FCS showed a more severe phenotype and higher prevalence of Show less

The biological functions and role in human diseases of lipoprotein (a) discovered more than 60 years ago are still not fully understood. The high homology of apo(a) with plasminogen initially leads us to think of Lp(a) as a player in the coagulation system as pro-thrombotic factor. Over the years, a solid body of evidence from biology, epidemiology and from genetics and mendelian randomization has contributed to identify Lp(a) as a causal factor of atherosclerotic coronary heart disease, aortic calcific valve stenosis and ischaemic stroke. The active involvement of Lp(a) in atherogenesis and aortic calcific valve stenosis has been demonstrated by experimental data regarding the role of oxidized phospholipids, which are the cargo of Lp(a) and the presence of a Lp(a) receptor in valve interstitial cells. In secondary prevention, patients optimally treated for low density lipoprotein cholesterol (LDL-C) but with high Lp(a) levels show a residual cardiovascular risk. To date the LDL-C affecting drugs have a marginal effect on Lp(a). Statins produce a modest increase, monoclonal PCSK9i and Inclisiran a modest decrease not sufficient to reduce significantly the risk associated to Lp(a). Only lipoprotein apheresis and obicetrapib, a CETP novel inhibitor, reduce respectively by 75% and 40% Lp(a) levels. To obtain a lifetime risk reduction of 50% similar to that achieved by reducing LDL-C of about 40 mg/dl, Lp(a) should be reduced of about 100 mg/dl. The ongoing trials on drugs such as ASO, SiRnas, assembly inhibitors and maybe in the future the gene editing could obtain these results. Show less

Apolipoprotein C-III (ApoC-III) is a widely known player in triglyceride metabolism, and it has been recently recognized as a polyhedric factor which may regulate several pathways beyond lipid metabolism by influencing cardiovascular, metabolic, and neurological disease risk. This review summarizes the different functions of ApoC-III and underlines the recent findings related to its multifaceted pathophysiological role. The role of ApoC-III has been implicated in HDL metabolism and in the development of atherosclerosis, inflammation, and ER stress in endothelial cells. ApoC-III has been recently considered an important player in insulin resistance mechanisms, lipodystrophy, diabetic dyslipidemia, and postprandial hypertriglyceridemia (PPT). The emerging evidence of the involvement of ApoC-III in the in the pathogenesis of Alzheimer's disease open the way to further study if modification of ApoC-III level slows disease progression. Furthermore, ApoC-III is clearly linked to cardiovascular disease (CVD) risk, and progression of coronary artery disease (CAD) as well as the calcification of aortic valve and recent clinical trials has pointed out the inhibition of ApoC-III as a promising approach to manage hypertriglyceridemia and prevent CVD. Several evidences highlight the role of ApoC-III not only in triglyceride metabolism but also in several cardio-metabolic pathways. Results from recent clinical trials underline that the inhibition of ApoC-III is a promising therapeutical strategy for the management of severe hypertriglyceridemia and in CVD prevention. Show less

Hyperalphalipoproteinemia (HALP) is a lipid disorder characterized by elevated plasma high-density lipoprotein cholesterol (HDL-C) levels above the 90th percentile of the distribution of HDL-C values in the general population. Secondary non-genetic factors such as drugs, pregnancy, alcohol intake, and liver diseases might induce HDL increases. Primary forms of HALP are caused by mutations in the genes coding for cholesteryl ester transfer protein (CETP), hepatic lipase (HL), apolipoprotein C-III (apo C-III), scavenger receptor class B type I (SR-BI) and endothelial lipase (EL). However, in the last decades, genome-wide association studies (GWAS) have also suggested a polygenic inheritance of hyperalphalipoproteinemia. Epidemiological studies have suggested that HDL-C is inversely correlated with cardiovascular (CV) risk, but recent Mendelian randomization data have shown a lack of atheroprotective causal effects of HDL-C. This review will focus on primary forms of HALP, the role of polygenic inheritance on HDL-C, associated risk for cardiovascular diseases and possible treatment options. Show less

A number of clinical findings suggested HDL-raising as a plausible approach to treat residual risk of CVD. However, lack of CVD risk reduction by elevated HDL cholesterol (HDL-C) through cholesterol ester transfer protein (CETP) inhibition and enhanced risk reduction in apolipoprotein A-I Milano (apoAI-M) individuals with low HDL-C shifted the focus from HDL-C level to HDL function. In the present study, we investigated correlations between HDL-C, HDL function, fecal cholesterol excretion, and Show less

Lipase maturation factor 1 (LMF1) gene is a novel candidate gene in severe hypertriglyceridemia. Lmf1 is involved in the maturation of lipoprotein lipase (LPL) and hepatic lipase in endoplasmic reticulum. To date only one patient with severe hypertriglyceridemia and related disorders was found to be homozygous for a nonsense mutation in LMF1 gene (Y439X). The objective of the study was to investigate LMF1 gene in hypertriglyceridemic patients in whom mutations in LPL, APOC2, and APOA5 genes had been excluded. The resequencing of LMF1 gene led to the discovery of a novel homozygous nonsense mutation in one patient with severe hypertriglyceridemia and recurrent episodes of pancreatitis. The mutation causes a G>A substitution in exon 9 (c.1395G>A), leading to a premature stop codon (W464X). LPL activity and mass were reduced by 76 and 50%, respectively, compared with normolipidemic controls. The proband over the years has shown a good response to treatment. The proband's son, heterozygous for the W464X, shows normal plasma triglyceride levels. We identified the second novel pathogenic mutation in LMF1 gene in a patient with severe hypertriglyceridemia. LPL deficiency in our patient was milder than in the carrier of the Y439X previously described. Show less