Recombinant human LCAT normalizes plasma lipoprotein profile in LCAT deficiency

Abnormal Lipoproteins Trigger Oxidative Stress-Mediated Apoptosis of Renal Cells in LCAT Deficiency

Familial lecithin:cholesterol acyltransferase (LCAT) deficiency (FLD) is a rare genetic disease caused by the loss of function mutations in the LCAT gene. LCAT deficiency is characterized by an abnormal lipoprotein profile with severe reduction in plasma levels of high-density lipoprotein (HDL) cholesterol and the accumulation of lipoprotein X (LpX). Renal failure is the major cause of morbidity and mortality in FLD patients; the pathogenesis of renal disease is only partly understood, but abnormalities in the lipoprotein profile could play a role in disease onset and progression. Serum and lipoprotein fractions from LCAT deficient carriers and controls were tested for renal toxicity on podocytes and tubular cells, and the underlying mechanisms were investigated at the cellular level. Both LpX and HDL from LCAT-deficient carriers triggered oxidative stress in renal cells, which culminated in cell apoptosis. These effects are partly explained by lipoprotein enrichment in unesterified cholesterol and ceramides, especially in the HDL fraction. Thus, alterations in lipoprotein composition could explain some of the nephrotoxic effects of LCAT deficient lipoproteins on podocytes and tubular cells.

Novel therapeutic opportunities for familial lecithin:cholesterol acyltransferase deficiency: promises and challenges

PURPOSE OF REVIEW

Genetic lecithin:cholesterol acyltransferase (LCAT) deficiency is a rare, inherited, recessive disease, which manifests as two different syndromes: Familial LCAT deficiency (FLD) and Fish-eye disease (FED), characterized by low HDL-C and corneal opacity. FLD patients also develop anaemia and renal disease. There is currently no therapy for FLD, but novel therapeutics are at different stages of development. Here, we summarize the most recent advances and the opportunities for and barriers to the further development of such therapies.

RECENT FINDINGS

Recent publications highlight the heterogeneous phenotype of FLD and the uncertainty over the natural history of disease and the factors contributing to disease progression. Therapies that restore LCAT function (protein and gene replacement therapies and LCAT activators) showed promising effects on markers of LCAT activity. Although they do not restore LCAT function, HDL mimetics may slow renal disease progression.

SUMMARY

The further development of novel therapeutics requires the identification of efficacy endpoints, which include quantitative biomarkers of disease progression. Because of the heterogeneity of renal disease progression among FLD individuals, future treatments for FLD will have to be tailored based on the specific clinical characteristics of the patient. Extensive studies of the natural history and biomarkers of the disease will be required to achieve this goal.

High-density lipoproteins, reverse cholesterol transport and atherogenesis

Plasma HDL-cholesterol concentrations correlate negatively with the risk of atherosclerotic cardiovascular disease (ASCVD). According to a widely cited model, HDL elicits its atheroprotective effect through its role in reverse cholesterol transport, which comprises the efflux of cholesterol from macrophages to early forms of HDL, followed by the conversion of free cholesterol (FCh) contained in HDL into cholesteryl esters, which are hepatically extracted from the plasma by HDL receptors and transferred to the bile for intestinal excretion. Given that increasing plasma HDL-cholesterol levels by genetic approaches does not reduce the risk of ASCVD, the focus of research has shifted to HDL function, especially in the context of macrophage cholesterol efflux. In support of the reverse cholesterol transport model, several large studies have revealed an inverse correlation between macrophage cholesterol efflux to plasma HDL and ASCVD. However, other studies have cast doubt on the underlying reverse cholesterol transport mechanism: in mice and humans, the FCh contained in HDL is rapidly cleared from the plasma (within minutes), independently of esterification and HDL holoparticle uptake by the liver. Moreover, the reversibility of FCh transfer between macrophages and HDL has implicated the reverse process - that is, the transfer of FCh from HDL to macrophages - in the aetiology of increased ASCVD under conditions of very high plasma HDL-FCh concentrations.

The effect of transgender hormonal treatment on high density lipoprotein cholesterol efflux capacity

BACKGROUND AND AIMS

A decrease in high-density lipoprotein (HDL)-cholesterol concentrations during transgender hormone therapy has been shown. However, the ability of HDL to remove cholesterol from arterial wall macrophages, termed cholesterol efflux capacity (CEC), has proven to be a better predictor of cardiovascular disease (CVD) largely independently of HDL-concentrations. In addition, the serum capacity to load macrophages with cholesterol (cholesterol loading capacity, CLC) represents an index of pro-atherogenic potential. As transgender individuals are exposed to lifelong exogenous hormone therapy (HT), it becomes of interest to study whether HDL-CEC and serum CLC are affected by HT. HDL-CEC and serum CLC have been evaluated in 15 trans men treated with testosterone and in 15 trans women treated with estradiol and cyproterone acetate at baseline and after 12 months of HT.

METHODS

Total HDL-CEC from macrophages and its major contributors, the ATP-binding cassette transporters (ABC) A1 and ABCG1 HDL-CEC and HDL-CEC by aqueous diffusion were determined by a radioisotopic assay. CLC was evaluated in human THP-1 macrophages.

RESULTS

In trans women, total HDL-CEC decreased by 10.8% (95%CI: -14.3;-7.3; p < 0.001), ABCA1 HDL-CEC by 23.8% (-34.7; -12.9; p < 0.001) and aqueous diffusion HDL-CEC by 4.8% (-8.4;-1.1; p < 0.01). In trans men, only aqueous diffusion HDL-CEC decreased significantly, -9.8% (-15.7;-3.9; p < 0.01). ABCG1 HDL-CEC did not change in either group. Serum CLC and HDL subclass distribution were not modified by HT in both groups.

CONCLUSIONS

Total HDL-CEC decreased during HT in trans women, with a specific reduction in ABCA1 CEC. This finding might contribute to a higher CVD risk.

Low Plasma Lecithin: Cholesterol Acyltransferase (LCAT) Concentration Predicts Chronic Kidney Disease

Low high-density lipoprotein-cholesterol (HDL-c) is the most remarkable lipid trait both in mild-to-moderate chronic kidney disease (CKD) patients as well as in advanced renal disease stages, and we have previously shown that reduced lecithin:cholesterol acyltransferase (LCAT) concentration is a major determinant of the low HDL phenotype. In the present study, we test the hypothesis that reduced LCAT concentration in CKD contributes to the progression of renal damage. The study includes two cohorts of subjects selected from the PLIC study: a cohort of 164 patients with CKD (NefroPLIC cohort) and a cohort of 164 subjects selected from the PLIC participants with a basal estimated glomerular filtration rate (eGFR) > 60 mL/min/1.73 m² (PLIC cohort). When the NefroPLIC patients were categorized according to the LCAT concentration, patients in the 1st tertile showed the highest event rate at follow-up with an event hazard ratio significantly higher compared to the 3rd LCAT tertile. Moreover, in the PLIC cohort, subjects in the 1st LCAT tertile showed a significantly faster impairment of kidney function compared to subjects in the 3rd LCAT tertile. Serum from subjects in the 1st LCAT tertile promoted a higher reactive oxygen species (ROS) production in renal cells compared to serum from subjects in the third LCAT tertile, and this effect was contrasted by pre-incubation with recombinant human LCAT (rhLCAT). The present study shows that reduced plasma LCAT concentration predicts CKD progression over time in patients with renal dysfunction, and, even more striking, it predicts the impairment of kidney function in the general population.

Recombinant LCAT (Lecithin:Cholesterol Acyltransferase) Rescues Defective HDL (High-Density Lipoprotein)-Mediated Endothelial Protection in Acute Coronary Syndrome

Objective- Aim of this study was to evaluate changes in LCAT (lecithin:cholesterol acyltransferase) concentration and activity in patients with an acute coronary syndrome, to investigate if these changes are related to the compromised capacity of HDL (high-density lipoprotein) to promote endothelial nitric oxide (NO) production, and to assess if rhLCAT (recombinant human LCAT) can rescue the defective vasoprotective HDL function. Approach and Results- Thirty ST-segment-elevation myocardial infarction (STEMI) patients were enrolled, and plasma was collected at hospital admission, 48 and 72 hours thereafter, at hospital discharge, and at 30-day follow-up. Plasma LCAT concentration and activity were measured and related to the capacity of HDL to promote NO production in cultured endothelial cells. In vitro studies were performed in which STEMI patients' plasma was added with rhLCAT and HDL vasoprotective activity assessed by measuring NO production in endothelial cells. The plasma concentration of the LCAT enzyme significantly decreases during STEMI with a parallel significant reduction in LCAT activity. HDL isolated from STEMI patients progressively lose the capacity to promote NO production by endothelial cells, and the reduction is related to decreased LCAT concentration. In vitro incubation of STEMI patients' plasma with rhLCAT restores HDL ability to promote endothelial NO production, possibly related to significant modification in HDL phospholipid classes. Conclusions- Impairment of cholesterol esterification may be a major factor in the HDL dysfunction observed during acute coronary syndrome. rhLCAT is able to restore HDL-mediated NO production in vitro, suggesting LCAT as potential therapeutic target for restoring HDL functionality in acute coronary syndrome.

Characterizing the Role of HMG-CoA Reductase in Aryl Hydrocarbon Receptor-Mediated Liver Injury in C57BL/6 Mice

The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor. The prototypical ligand of the AHR is an environmental contaminant called 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). TCDD exposure is associated with many adverse health outcomes in humans including non-alcoholic fatty liver disease (NAFLD). Previous studies suggest that AHR ligands alter cholesterol homeostasis in mice through repression of genes involved in cholesterol biosynthesis, such as Hmgcr, which encodes the rate-limiting enzyme of cholesterol biosynthesis called 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (HMGCR). In this study, we sought to characterize the impact of HMGCR repression in TCDD-induced liver injury. C57BL/6 mice were exposed to TCDD in the presence or absence of simvastatin, a competitive inhibitor of HMGCR. Simvastatin exposure decreased TCDD-induced hepatic lipid accumulation in both sexes, but was most prominent in females. Simvastatin and TCDD (S + T) co-treatment increased hepatic AHR-battery gene expression and liver injury in male, but not female, mice. In addition, the S + T co-treatment led to an increase in hepatic glycogen content that coincides with heavier liver in female mice. Results from this study suggest that statins, which are amongst the most prescribed pharmaceuticals, may protect from AHR-mediated steatosis, but alter glycogen metabolism and increase the risk of TCDD-elicited liver damage in a sex-specific manner.

The P274S Mutation of Lecithin-Cholesterol Acyltransferase (LCAT) and Its Clinical Manifestations in a Large Kindred

RATIONALE & OBJECTIVE

Lecithin-cholesterol acyltransferase (LCAT) catalyzes the maturation of high-density lipoprotein. Homozygosity for loss-of-function mutations causes familial LCAT deficiency (FLD), characterized by corneal opacities, anemia, and renal involvement. This study sought to characterize kidney biopsy findings and clinical outcomes in a family with FLD.

STUDY DESIGN

Prospective observational study.

SETTING & PARTICIPANTS

2 (related) index patients with clinically apparent FLD were initially identified. 110 of 122 family members who consented to genetic analysis were also studied.

PREDICTORS

Demographic and laboratory parameters (including lipid profiles and LCAT activity) and full sequence analysis of the LCAT gene. Kidney histologic examination was performed with samples from 6 participants.

OUTCOMES

Cardiovascular and renal events during a median follow-up of 12 years. Estimation of annual rate of decline in glomerular filtration rate.

ANALYTICAL APPROACH

Analysis of variance, linear regression analysis, and Fine-Gray competing-risk survival analysis.

RESULTS

9 homozygous, 57 heterozygous, and 44 unaffected family members were identified. In all affected individuals, full sequence analysis of the LCAT gene revealed a mutation (c.820C>T) predicted to cause a proline to serine substitution at amino acid 274 (P274S). Homozygosity caused a complete loss of LCAT activity. Kidney biopsy findings demonstrated lipid deposition causing glomerular basement membrane thickening, mesangial expansion, and "foam-cell" infiltration of kidney tissue. Tubular atrophy, glomerular sclerosis, and complement fixation were associated with worse kidney outcomes. Estimated glomerular filtration rate deteriorated among homozygous family members at an average annual rate of 3.56 mL/min/1.73 m². The incidence of cardiovascular and renal complications was higher among homozygous family members compared with heterozygous and unaffected members. Mild thrombocytopenia was a common finding among homozygous participants.

LIMITATIONS

The presence of cardiovascular disease was mainly based on medical history.

CONCLUSIONS

The P274S LCAT mutation was found to cause FLD with renal involvement. Tubular atrophy, glomerular sclerosis, and complement fixation were associated with a worse renal prognosis.

Paradoxical fall in proteinuria during pregnancy in an LCAT-deficient patient-A case report

A 29-year-old lady was diagnosed with lecithin:cholesterol acyltransferase (LCAT) deficiency having presented with bilateral corneal clouding, severely reduced high density lipoproteins cholesterol, and proteinuria. She is a compound heterozygote with two LCAT gene mutations, one of which is novel, c.321C>A in exon 3. Surprisingly, the level of proteinuria significantly improved during pregnancy, despite stopping the angiotensin-converting enzyme inhibitor. However, LCAT concentration and activity remained identical during pregnancy and postpartum. Her pregnancy was complicated by rising triglyceride levels from the second trimester requiring treatment with omega-3 fatty acid and fenofibrate. In the last trimester, a further complication arose when she became hypertensive and proteinuria worsened. She was diagnosed with pre-eclampsia and had an emergency cesarean section at 39 weeks delivering a healthy baby. This case adds to the knowledge of the pathophysiology of LCAT deficiency during pregnancy and will be useful in future patient management.

Novel Missense LCAT Gene Mutation Associated with an Atypical Phenotype of Familial LCAT Deficiency in Two Portuguese Brothers

Familial lecithin-cholesterol acyltransferase deficiency (FLD) is a rare recessive disorder of cholesterol metabolism, caused by loss-of-function mutations in the human LCAT gene, leading to alterations in the lipid/lipoprotein profile, with extremely low HDL levels.The classical FLD phenotype is characterized by diffuse corneal opacification, haemolytic anaemia and proteinuric chronic kidney disease (CKD); an incomplete form, only affecting the corneas, has been reported in a few families worldwide.We describe an intermediate phenotype of LCAT deficiency, with CKD preceding the development of corneal clouding, in two Portuguese brothers apparently homozygous for a novel missense LCAT gene mutation. The atypical phenotype, the diagnosis of membranous nephropathy in the proband's native kidney biopsy, the late-onset and delayed recognition of the corneal opacification, the co-segregation with Gilbert syndrome and the late recurrence of the primary disease in kidney allograft all contributed to obscure the diagnosis of an LCAT deficiency syndrome for many years.A major teaching point is that on standard light microscopy examination the kidney biopsies of patients with LCAT deficiency with residual enzyme activity may not show significant vacuolization and may be misdiagnosed as membranous nephropathy. The cases of these two patients also illustrate the importance of performing detailed physical examination in young adults presenting with proteinuric CKD, as the most important clue to the diagnosis of FLD is in the eyes.

HDL-cholesterol and cardiovascular disease: rethinking our approach

PURPOSE OF REVIEW

A low level of plasma high density lipoprotein cholesterol (HDL-C) is a strong and independent risk factor for atherosclerotic cardiovascular disease (ASCVD). However, several large studies recently revealed that pharmacologic interventions that increase HDL-C concentration have not improved cardiovascular outcomes when added to standard therapy. In addition, specific genetic variants that raise HDL-C levels are not clearly associated with reduced risk of coronary heart disease. These observations have challenged the 'HDL hypothesis' that HDL-C is causally related to ASCVD and that intervention to raise HDL-C will reduce ASCVD events. This article will present the current data on the HDL hypothesis and provide a revised paradigm of considering HDL in the atherosclerotic pathway.

RECENT FINDINGS

Recent evidence has shed light on the complex nature of HDL-C metabolism and function. There are compelling data that the ability of HDL to promote cholesterol efflux from macrophages, the first step in the 'reverse cholesterol transport' (RCT) pathway, is inversely associated with risk for ASCVD even after controlling for HDL-C. This has led to the 'HDL flux hypothesis' that therapeutic intervention that targets macrophage cholesterol efflux and RCT may reduce risk. Preclinical studies of such interventions show promise and early phase clinical studies, though small, are encouraging.

SUMMARY

The role of HDL-C in modulating atherosclerotic disease is as yet uncertain. However, new findings and therapies targeting HDL-C show early promise and may provide an important intervention in attenuating the burden of ASCVD in the future.

Identification of candidate diagnostic biomarkers for adolescent idiopathic scoliosis using UPLC/QTOF-MS analysis: a first report of lipid metabolism profiles

Adolescent idiopathic scoliosis (AIS) is a complex spine deformity, affecting approximately 1–3% adolescents. Earlier diagnosis could increase the likelihood of successful conservative treatment and hence reduce the need for surgical intervention. We conducted a serum metabonomic study to explore the potential biomarkers of AIS for early diagnosis. Serum metabolic profiles were firstly explored between 30 AIS patients and 31 healthy controls by ultra high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. Then, the candidate metabolites were validated in an independent cohort including 31 AIS patients and 44 controls. The results showed that metabolic profiles of AIS patients generally deviated from healthy controls in both the discovery set and replication set. Seven differential metabolites were identified as candidate diagnostic biomarkers, including PC(20:4), 2-hexenoylcarnitine, beta-D-glucopyranuronicacid, DG(38:9), MG(20:3), LysoPC(18:2) and LysoPC(16:0). These candidate metabolites indicated disrupted lipid metabolism in AIS, including glycerophospholipid, glycerolipid and fatty acid metabolism. Elevated expressions of adipose triglyceride lipase and hormone sensitive lipase in adipose tissue further corroborated our findings of increased lipid metabolism in AIS. Our findings suggest that differential metabolites discovered in AIS could be used as potential diagnostic biomarkers and that lipid metabolism plays a role in the pathogenesis of AIS.

Management of lipoprotein X and its complications in a patient with primary sclerosing cholangitis

Lipoprotein X (LpX) is an abnormal lipoprotein found in conditions such as lecithin:cholesterol acyltransferase deficiency and cholestatic states (e.g., primary biliary cirrhosis and primary sclerosing cholangitis). Management of severe hypercholesterolemia due to LpX with drugs and physical removal methods is not well established in the literature. A case is discussed of a 51-year-old woman who presented with multiple electrolyte abnormalities, xanthomas and neuropathy found to be secondary to LpX in the setting of primary sclerosing cholangitis. This case highlights that oral medications, including statins, may be insufficient to normalize lipid levels or improve clinical symptoms of LpX and presents therapeutic plasma exchange as a safe and effective therapeutic option to treat the morbid sequela of LpX hyperlipidemia.

Advances in the Study of the Antiatherogenic Function and Novel Therapies for HDL

The hypothesis that raising high-density lipoprotein cholesterol (HDL-C) levels could improve the risk for cardiovascular disease (CVD) is facing challenges. There is multitudinous clear clinical evidence that the latest failures of HDL-C-raising drugs show no clear association with risks for CVD. At the genetic level, recent research indicates that steady-state HDL-C concentrations may provide limited information regarding the potential antiatherogenic functions of HDL. It is evident that the newer strategies may replace therapeutic approaches to simply raise plasma HDL-C levels. There is an urgent need to identify an efficient biomarker that accurately predicts the increased risk of atherosclerosis (AS) in patients and that may be used for exploring newer therapeutic targets. Studies from recent decades show that the composition, structure and function of circulating HDL are closely associated with high cardiovascular risk. A vast amount of data demonstrates that the most important mechanism through which HDL antagonizes AS involves the reverse cholesterol transport (RCT) process. Clinical trials of drugs that specifically target HDL have so far proven disappointing, so it is necessary to carry out review on the HDL therapeutics.

Acquired lecithin:cholesterol acyltransferase deficiency as a major factor in lowering plasma HDL levels in chronic kidney disease

OBJECTIVES

It has been suggested that a low plasma high-density lipoprotein cholesterol (HDL-C) level contributes to the high cardiovascular disease risk of patients with chronic kidney disease (CKD), especially those undergoing haemodialysis (HD). The present study was conducted to gain further understanding of the mechanism(s) responsible for the low HDL-C levels in patients with CKD and to separate the impact of HD from that of the underlying CKD.

METHODS

Plasma lipids and lipoproteins, HDL subclasses and various cholesterol esterification parameters were measured in a total of 248 patients with CKD, 198 of whom were undergoing HD treatment and 40 healthy subjects.

RESULTS

Chronic kidney disease was found to be associated with highly significant reductions in plasma HDL-C, unesterified cholesterol, apolipoprotein (apo)A-I, apoA-II and LpA-I:A-II levels in both CKD cohorts (with and without HD treatment). The cholesterol esterification process was markedly impaired, as indicated by reductions in plasma lecithin:cholesterol acyltransferase (LCAT) concentration and activity and cholesterol esterification rate, and by an increase in the plasma preβ-HDL content. HD treatment was associated with a further lowering of HDL levels and impaired plasma cholesterol esterification. The plasma HDL-C level was highly significantly correlated with LCAT concentration (R = 0.438, P < 0.001), LCAT activity (R = 0.243, P < 0.001) and cholesterol esterification rate (R = 0.149, P = 0.031). Highly significant correlations were also found between plasma LCAT concentration and levels of apoA-I (R = 0.432, P < 0.001), apoA-II (R = 0.275, P < 0.001), LpA-I (R = 0.326, P < 0.001) and LpA-I:A-II (R = 0.346, P < 0.001).

CONCLUSION

Acquired LCAT deficiency is a major cause of low plasma HDL levels in patients with CKD, thus LCAT is an attractive target for therapeutic intervention to reverse dyslipidaemia, and possibly lower the cardiovascular disease risk in these patients.

Novel concepts in HDL pharmacology

High-density lipoproteins (HDL) are a target for drug development because of their proposed anti-atherogenic properties. In this review, we will briefly discuss the currently established drugs for increasing HDL-C, namely niacin and fibrates, and some of their limitations. Next, we will focus on novel alternative therapies that are currently being developed for raising HDL-C, such as CETP inhibitors. Finally, we will conclude with a review of novel drugs that are being developed for modulating the function of HDL based on HDL mimetics. Gaps in our knowledge and the challenges that will have to be overcome for these new HDL based therapies will also be discussed.

High-density lipoprotein metabolism, composition, function, and deficiency

PURPOSE OF REVIEW

To examine the recent advances in our knowledge of HDL metabolism, composition, function, and coronary heart disease (CHD), as well as marked HDL deficiency states because of mutations in the apolipoprotein (apo) A-I, ATP-binding cassette transfer protein A1 and lecithin cholesterol acyltransferase (LCAT) gene loci.

RECENT FINDINGS

It has been documented that apoA-I, myeloperoxidase and paraoxonase 1 (PON1) form a complex in HDL that is critical for HDL binding and function. Myeloperoxidase has a negative impact on HDL function, whereas PON1 has a beneficial effect. Patients who lack apoA-I develop markedly premature CHD. Patients who lack ATP-binding cassette transfer protein A1 transporter function have only very small discoidal preβ-1 HDL, and develop hepatosplenomegaly, intermittent neuropathy and premature CHD, although significant heterogeneity for these disorders has been reported. Patients with LCAT deficiency have abnormal small discoidal LDLs and HDL particles, and develop kidney failure. Enzyme replacement therapy is being developed for the latter disorder.

SUMMARY

Recent data indicates that proteins other than apoA-I and apoA-II such as MPO and PON1 have important effects on HDL function. There has been considerable recent progress made in our understanding of HDL protein content and function.

Distant homology modeling of LCAT and its validation through in silico targeting and in vitro and in vivo assays

LCAT (lecithin:cholesterol acyltransferase) catalyzes the transacylation of a fatty acid of lecithin to cholesterol, generating a cholesteryl ester and lysolecithin. The knowledge of LCAT atomic structure and the identification of the amino acids relevant in controlling its structure and function are expected to be very helpful to understand the enzyme catalytic mechanism, as involved in HDL cholesterol metabolism. However - after an early report in the late ‘90 s - no recent advance has been made about LCAT three-dimensional structure. In this paper, we propose an LCAT atomistic model, built following the most up-to-date molecular modeling approaches, and exploiting newly solved crystallographic structures. LCAT shows the typical folding of the α/β hydrolase superfamily, and its topology is characterized by a combination of α-helices covering a central 7-strand β-sheet. LCAT presents a Ser/Asp/His catalytic triad with a peculiar geometry, which is shared with such other enzyme classes as lipases, proteases and esterases. Our proposed model was validated through different approaches. We evaluated the impact on LCAT structure of some point mutations close to the enzyme active site (Lys218Asn, Thr274Ala, Thr274Ile) and explained, at a molecular level, their phenotypic effects. Furthermore, we devised some LCAT modulators either designed through a de novo strategy or identified through a virtual high-throughput screening pipeline. The tested compounds were proven to be potent inhibitors of the enzyme activity.