Influence of triglyceride concentration in lipoprotein (a) as a function of dyslipidemia. / Influencia de la concentración de triglicéridos en la lipoproteína(a) en función de la dislipidemia.

BACKGROUND: Recently, an inverse relationship between the blood concentration of lipoprotein(a) (Lp(a)) and triglycerides (TG) has been demonstrated. The larger the VLDL particle size, the greater the presence of VLDL rich in apoliprotein E and in subjects with the apoE2/E2 genotype, the lower Lp(a) concentration. The mechanism of this inverse association is unknown. The objective of this analysis was to evaluate the Lp(a)-TG association in patients treated at the lipid units included in the registry of the Spanish Society of Atherosclerosis (SEA) by comparing the different dyslipidemias. PATIENTS AND METHODS: Five thousand two hundred and seventy-five subjects ≥18 years of age registered in the registry before March 31, 2023, with Lp(a) concentration data and complete lipid profile information without treatment were included. RESULTS: The mean age was 53.0 ± 14.0 years, with 48% women. The 9.5% of subjects (n = 502) had diabetes and the 22.4% (n = 1184) were obese. The median TG level was 130 mg/dL (IQR 88.0-210) and Lp(a) 55.0 nmol/L (IQR 17.9-156). Lp(a) concentration showed a negative association with TG concentration when TG values exceeded 300 mg/dL. Subjects with TG > 1000 mg/dL showed the lowest level of Lp(a), 17.9 nmol/L, and subjects with TG < 300 mg/dL had a mean Lp(a) concentration of 60.1 nmol/L. In subjects without diabetes or obesity, the inverse association of Lp(a)-TG was especially important (p < 0.001). The median Lp(a) was 58.3 nmol/L in those with TG < 300 mg/dL and 22.0 nmol/L if TG > 1000 mg/dL. No association was found between TG and Lp(a) in subjects with diabetes and obesity, nor in subjects with familial hypercholesterolemia. In subjects with multifactorial combined hyperlipemia with TG < 300 mg/dL, Lp(a) was 64.6 nmol/L; in the range of 300-399 mg/dL of TG, Lp(a) decreased to 38. 8 nmol/L, and up to 22.3 nmol/L when TG > 1000 mg/dL. CONCLUSIONS: Our results show an inverse Lp(a)-TG relationship in TG concentrations > 300 mg/dL in subjects without diabetes, obesity and without familial hypercholesterolemia. Our results suggest that, in those hypertriglyceridemias due to hepatic overproduction of VLDL, the formation of Lp(a) is reduced, unlike those in which the peripheral catabolism of TG-rich lipoproteins is reduced.

Current causes of death in familial hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) is a codominant autosomal disease characterized by high low-density lipoprotein cholesterol (LDLc) and a high risk of premature cardiovascular disease (CVD). The molecular bases have been well defined, and effective lipid lowering is possible. This analysis aimed to study the current major causes of death of genetically defined heterozygous familial hypercholesterolemia (heFH). METHODS: A case‒control study was designed to analyse life-long mortality in a group of heFH and control families. Data from first-degree family members of cases and controls (nonconsanguineous cohabitants), including deceased relatives, were collected from a questionnaire and review of medical records. Mortality was compared among heFH patients, nonheFH patients, and nonconsanguineous family members. RESULTS: A total of 813 family members were analysed, 26.4% of whom were deceased. Among the deceased, the mean age of death was 69.3 years in heFH individuals, 73.5 years in nonheFH individuals, and 73.2 years in nonconsanguineous individuals, without significant differences. CVD was the cause of death in 59.7% of heFH individuals, 37.7% of nonheFH individuals, and 37.4% of nonconsanguineous individuals (P = 0.012). These differences were greater after restricting the analyses to parents. The hazard ratio of dying from CVD was 2.85 times higher (95% CI, (1.73-4.69) in heFH individuals than in individuals in the other two groups (non-FH and nonconsanguineous), who did not differ in their risk. CONCLUSIONS: CVD mortality in heFH individuals is lower and occurs later than that described in the last century but is still higher than that in non-FH individuals. This improved prognosis of CVD risk is not associated with changes in non-CVD mortality.

Maternally inherited hypercholesterolemia does not modify the cardiovascular phenotype in familial hypercholesterolemia.

BACKGROUND AND AIMS: Familial hypercholesterolemia (FH) is a codominant autosomal disease characterized by a high risk of cardiovascular disease when not in lipid-lowering treatment. However, there is a large variability in the clinical presentation in heterozygous subjects (HeFH). Maternal hypercholesterolemia has been proposed as a cardiometabolic risk factor later in life. Whether this phenotype variability depends on the mother or father origin of hypercholesterolemia is unknown. The objective of this study was to analyze potential differences in anthropometry, superficial lipid deposits, comorbidities, and lipid concentrations depending on the parental origin of hypercholesterolemia within a large group of HeFH. METHODS: This is a cross-sectional observational, multicenter, nation-wide study in Spain. We recruited adults with HeFH to study clinical differences according to the parental origin. Data on HeFH patients were obtained from the Dyslipidemia Registry of the Spanish Atherosclerosis Society. RESULTS: HeFH patients were grouped in 1231 HeFH-mother-offspring aged 45.7 (16.3) years and 1174 HeFH-father-offspring aged 44.8 (16.7) years. We did not find any difference in lipid parameters (total cholesterol, triglycerides, LDLc, HDLc, and Lp(a)), nor in the comorbidities studied (cardiovascular disease prevalence, age of onset of cardiovascular disease, obesity, diabetes, and hypertension) between groups. Lipid-lowering treatment did not differ between groups. The prevalence of comorbidities did not show differences when they were studied by age groups. CONCLUSIONS: Our research with a large group of subjects with HeFH shows that a potential maternal effect is not relevant in FH. However, due to the size of our sample, potential differences between genders cannot be completely ruled out. This implies that severe maternal hypercholesterolemia during pregnancy is not associated with additional risk in the FH affected offspring.

Three Dimensional Carotid and Femoral Ultrasound is not Superior to Two Dimensional Ultrasound as a Predictor of Coronary Atherosclerosis Among Men With Intermediate Cardiovascular Risk.

BACKGROUND: Current cardiovascular disease (CVD) risk stratification scales, drawn up from traditional risk factors, have important limitations. The detection of subclinical atherosclerosis, by a non-invasive technique such as peripheral arteries ultrasound (US) may improve cardiovascular risk (CVR) stratification, especially in intermediate risk population. Our aim was to compare the predictive power of atherosclerotic plaques detected in carotid and femoral arteries by 2-dimensional (2D) vs. 3-dimensional (3D) US for positive coronary artery calcium score (CACS), used as a proxy for CVD, in a middle-aged sample with intermediate 10-year CVR (7.5-20%). METHODS: To detect atherosclerotic plaques by 2D vs. 3D US scan of carotid and femoral arteries and comparison of their association with CACS obtained by computed tomography (CT) of subjects with intermediate CVR belonging to the Aragon Workers' Health Study. RESULTS: 120 men were included, with a 10.4% average 10 years CVR. Forty-one (34.2%) participants had CACS ≥ 1. 90 participants (75%) had at least one plaque detected by 2D scan while 85 participants (70.8%) had at least a plaque detected by 3D US. Conventional CVR estimates c-statistic for CACS was .590. Although the variables most predicted of CACS ≥ 1 were those measured by 3D US (total plaque volume and mean of plaque density, c-statistics: .743 and .750 respectively), their predictive capacity was not statistically significantly different from the number of territories with plaque, measured either by 2D and 3D US (c-statistics .728 to .740 respectively). CONCLUSION: Subclinical atherosclerosis measured by 2D and 3D US were better predictors of CACS ≥ 1 than CVR estimated by conventional guidelines. In our sample, 3D US did not show any significant advantages with respect to 2D US for the prediction of coronary atherosclerosis.

The island of Gran Canaria: A genetic isolate for familial hypercholesterolemia.

BACKGROUND: Genetic diagnosis of familial hypercholesterolemia (FH) has not been universally performed in the Canary Islands (Spain). OBJECTIVES: This study aimed to genetically characterize a cohort of patients with FH in the island of Gran Canaria. METHODS: Study subjects were 70 unrelated index cases attending a tertiary hospital in Gran Canaria, with a clinical diagnosis of FH, according to the criteria of the Dutch Lipid Clinic Network. Given that 7 of the first 10 cases with positive genetic study were carriers of a single mutation in the LDLR gene [p.(Tyr400_Phe402del)], a specific polymerase chain reaction-based assay was developed for the detection of this variant as a first screening step on the remaining subjects. In those without this mutation, molecular diagnosis was completed using a next-generation sequencing panel including LDLR, APOB, PCSK9, LDLRAP1, APOE, STAP1, and LIPA genes and incorporating copy number variation detection in LDLR. RESULTS: On the whole, 44 subjects (62%) had a positive genetic study, of whom 30 (68%) were heterozygous carriers of the p.(Tyr400_Phe402del) variant. Eleven subjects carried other mutations in LDLR, including the novel mutation NM_000527.4: c.877dupG; NP_000518.1: p.(Asp293Glyfs*8). An unclassified PCSK9 gene variant was found in one subject [(NM_174936.3:c.1496G>A; NP_777596.2: p.(Arg499His)]. Other single patients had mutations in APOB (heterozygous) and in LIPA (homozygous). All identified variants co-segregated with the disease phenotype. CONCLUSIONS: These findings suggest a founder effect for the p.(Tyr400_Phe402del) LDLR mutation in Gran Canaria. A cost-effective local screening strategy for genetic diagnosis of FH could be implemented in this region.

Lipid-lowering response in subjects with the p.(Leu167del) mutation in the APOE gene.

BACKGROUND AND AIMS: The aim of this work was to compared the effect of lipid lowering drugs among familial hypercholesterolemia (FH) subjects with a functional mutation in LDLR (LDLR FH) and FH with the p.(Leu167del) mutation in APOE. METHODS: We retrospectively selected all adults with the p.(Leu167del) mutation on lipid-lowering treatment (n = 22) attending the Lipid Unit at the Hospital Miguel Servet. Age and sex matched LDLR FH from the same Unit were randomly selected as a control group (n = 44). RESULTS: The mean percentage reduction in LDLc was significantly higher in the p.(Leu167del) carriers (-52.1%) than in the LDLR FH (-39.7%) (p = 0.040) when on high intensity statins. Similar differences between groups were observed in non-HDLc -49.4% and -36.4%, respectively (p = 0.030). CONCLUSIONS: Subjects with p.(Leu167del) mutation have a higher lipid-lowering response to statins with or without ezetimibe than LDLR FH. This supports the use of genetics for a more efficient management of FH.

Association between non-cholesterol sterol concentrations and Achilles tendon thickness in patients with genetic familial hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) is a genetic disorder that result in abnormally high low-density lipoprotein cholesterol levels, markedly increased risk of coronary heart disease (CHD) and tendon xanthomas (TX). However, the clinical expression is highly variable. TX are present in other metabolic diseases that associate increased sterol concentration. If non-cholesterol sterols are involved in the development of TX in FH has not been analyzed. METHODS: Clinical and biochemical characteristics, non-cholesterol sterols concentrations and Aquilles tendon thickness were determined in subjects with genetic FH with (n = 63) and without (n = 40) TX. Student-t test o Mann-Whitney test were used accordingly. Categorical variables were compared using a Chi square test. ANOVA and Kruskal-Wallis tests were performed to multiple independent variables comparison. Post hoc adjusted comparisons were performed with Bonferroni correction when applicable. Correlations of parameters in selected groups were calculated applying the non-parametric Spearman correlation procedure. To identify variables associated with Achilles tendon thickness changes, multiple linear regression were applied. RESULTS: Patients with TX presented higher concentrations of non-cholesterol sterols in plasma than patients without xanthomas (P = 0.006 and 0.034, respectively). Furthermore, there was a significant association between 5α-cholestanol, ß-sitosterol, desmosterol, 24S-hydroxycholesterol and 27-hydroxycholesterol concentrations and Achilles tendon thickness (p = 0.002, 0.012, 0.020, 0.045 and 0.040, respectively). CONCLUSIONS: Our results indicate that non-cholesterol sterol concentrations are associated with the presence of TX. Since cholesterol and non-cholesterol sterols are present in the same lipoproteins, further studies would be needed to elucidate their potential role in the development of TX.

Single Nucleotide Variants Associated With Polygenic Hypercholesterolemia in Families Diagnosed Clinically With Familial Hypercholesterolemia.

INTRODUCTION AND OBJECTIVES: Approximately 20% to 40% of clinically defined familial hypercholesterolemia cases do not show a causative mutation in candidate genes, and some of them may have a polygenic origin. A cholesterol gene risk score for the diagnosis of polygenic hypercholesterolemia has been demonstrated to be valuable to differentiate polygenic and monogenic hypercholesterolemia. The aim of this study was to determine the contribution to low-density lipoprotein cholesterol (LDL-C) of the single nucleotide variants associated with polygenic hypercholesterolemia in probands with genetic hypercholesterolemia without mutations in candidate genes (nonfamilial hypercholesterolemia genetic hypercholesterolemia) and the genetic score in cascade screening in their family members. METHODS: We recruited 49 nonfamilial hypercholesterolemia genetic hypercholesterolemia families (294 participants) and calculated cholesterol gene scores, derived from single nucleotide variants in SORT1, APOB, ABCG8, APOE and LDLR and lipoprotein(a) plasma concentration. RESULTS: Risk alleles in SORT1, ABCG8, APOE, and LDLR showed a statistically significantly higher frequency in blood relatives than in the 1000 Genomes Project. However, there were no differences between affected and nonaffected members. The contribution of the cholesterol gene score to LDL-C was significantly higher in affected than in nonaffected participants (P = .048). The percentage of the LDL-C variation explained by the score was 3.1%, and this percentage increased to 6.9% in those families with the highest genetic score in the proband. CONCLUSIONS: Nonfamilial hypercholesterolemia genetic hypercholesterolemia families concentrate risk alleles for high LDL-C. Their contribution varies greatly among families, indicating the complexity and heterogeneity of these forms of hypercholesterolemias. The gene score explains a small percentage of LDL-C, which limits its use in diagnosis.

ABCG5/G8 gene is associated with hypercholesterolemias without mutation in candidate genes and noncholesterol sterols.

CONTEXT: Approximately 20% to 40% of clinically defined familial hypercholesterolemia (FH) cases do not show a causative mutation in candidate genes (mutation-negative FH), and some of them may have a polygenic origin. OBJECTIVE: The aim of this work was to study the prevalence of ABCG5/G8 genetic variants in mutation-negative FH, as defects in these genes relate to intestinal hyperabsorption of cholesterol and thus ABCG5/G8 variants could explain in part the mechanism of hypercholesterolemia. DESIGN, SETTING, AND PATIENTS: We sequenced the ABCG5/G8 genes in 214 mutation-negative FH and 97 controls. Surrogate markers of cholesterol absorption (5α-cholestanol, ß-sitosterol, campesterol, stigmasterol, and sitostanol) were quantified by high-performance liquid chromatography-tandem mass spectrometry in both studied groups. RESULTS: We found 8 mutation-negative FH patients (3.73%) with a pathogenic mutation in ABCG5/G8 genes. We observed significantly higher concentration of surrogate markers of cholesterol absorption in mutation-negative FH than in controls. In addition, we found significantly higher concentrations of cholesterol absorption markers in mutation-negative FH with ABCG5/G8 defects than in mutation-negative, ABCG5/G8-negative FH. A gene score reflecting the number of common single nucleotide variants associated with hypercholesterolemia was significantly higher in cases than in controls (P = .032). Subjects with a gene score above the mean had significantly higher 5α-cholestanol and stigmasterol than those with a lower gene score. CONCLUSIONS: Mutation-negative FH subjects accumulate an excess of rare and common gene variations in ABCG5/G8 genes. This variation is associated with increased intestinal absorption of cholesterol, as determined by surrogate makers, suggesting that these loci contribute to hypercholesterolemia by enhancing intestinal cholesterol absorption.

Effect of intensive LDL cholesterol lowering with PCSK9 monoclonal antibodies on tendon xanthoma regression in familial hypercholesterolemia.

BACKGROUND AND AIMS: The effect of LDLc lowering with PCSK9 antibodies on tendon xanthomas (TX) is unknown. METHODS: TX was measured in 24 heterozygous familial hypercholesterolemia (HeFH) cases and in 24 HeFH controls with or without PCSK9 inhibitors for at least one year. RESULTS: Exposure to PCSK9 inhibitors in cases was 2.96 ± 1.33 years. LDLc decreased 80.8 ± 7.66% in cases and 56.9 ± 11.1% in controls. There was a decrease in maximum (-5.03%) and mean (-5.32%) TX in cases but not in controls (+3.97%, +3.16, respectively, p = 0.01). PCSK9 inhibitor treatment was independently associated with TX reduction. CONCLUSION: Addition of a PCSK9 inhibitor to statin and ezetimibe resulted in a greater decrease in LDLc and TX after 3 years of treatment.

Association Between the Presence of Carotid Artery Plaque and Cardiovascular Events in Patients With Genetic Hypercholesterolemia.

INTRODUCTION AND OBJECTIVES: The equations used in the general population to calculate cardiovascular risk are not useful in genetic hypercholesterolemia (GH). Carotid plaque detection has proved useful in cardiovascular prediction and risk reclassification but there have been no studies of its usefulness in GH. The aim of this study was to determine the association between the presence of carotid artery plaque and the occurrence of cardiovascular events in patients with GH. METHODS: This study included 1778 persons with GH. The mean follow-up until the occurrence of cardiovascular events was 6.26 years. At presentation, the presence of carotid artery plaque was studied by high-resolution ultrasound. RESULTS: Carotid artery plaque was found in 661 (37.2%) patients: 31.9% with familial hypercholesterolemia, 39.8% with familial combined hyperlipidemia, 45.5% with dysbetalipoproteinemia, and 43.2% with polygenic hypercholesterolemia. During follow-up, 58 patients had a cardiovascular event. Event rates were 6354/100 000 (95%CI, 4432.4-8275.6) in the group with plaque and 1432/100 000 (95%CI, 730.6-2134.3) in the group without plaque, with significant differences between the 2 groups (P < .001). The relative risk of an event was 4.34 (95CI%, 2.44-7.71; P < .001) times higher in patients with plaque and was 2.40 (95%CI, 1.27-4.56; P = .007) times higher after adjustment for major risk factors. The number of carotid artery plaques was positively associated with the risk of cardiovascular events. CONCLUSIONS: Most cardiovascular events occur in a subgroup of patients who can be identified by carotid plaque detection. These results support the use of plaque screening in this population and should help in risk stratification and treatment in GH.

The p.Leu167del Mutation in APOE Gene Causes Autosomal Dominant Hypercholesterolemia by Down-regulation of LDL Receptor Expression in Hepatocytes.

CONTEXT: The p.Leu167del mutation in the APOE gene has been associated with hyperlipidemia. OBJECTIVES: Our objective was to determine the frequency of p.Leu167del mutation in APOE gene in subjects with autosomal dominant hypercholesterolemia (ADH) in whom LDLR, APOB, and PCSK9 mutations had been excluded and to identify the mechanisms by which this mutant apo E causes hypercholesterolemia. DESIGN: The APOE gene was analyzed in a case-control study. SETTING: The study was conducted at a University Hospital Lipid Clinic. PATIENTS OR OTHER PARTICIPANTS: Two groups (ADH, 288 patients; control, 220 normolipidemic subjects) were included. INTERVENTION: We performed sequencing of APOE gene and proteomic and cellular experiments. MAIN OUTCOME MEASURE: To determine the frequency of the p.Leu167del mutation and the mechanism by which it causes hypercholesterolemia. RESULTS: In the ADH group, nine subjects (3.1%) were carriers of the APOE c.500_502delTCC, p.Leu167del mutation, cosegregating with hypercholesterolemia in studied families. Proteomic quantification of wild-type and mutant apo E in very low-density lipoprotein (VLDL) from carrier subjects revealed that apo E3 is almost a 5-fold increase compared to mutant apo E. Cultured cell studies revealed that VLDL from mutation carriers had a significantly higher uptake by HepG2 and THP-1 cells compared to VLDL from subjects with E3/E3 or E2/E2 genotypes. Transcriptional down-regulation of LDLR was also confirmed. CONCLUSIONS: p.Leu167del mutation in APOE gene is the cause of hypercholesterolemia in the 3.1% of our ADH subjects without LDLR, APOB, and PCSK9 mutations. The mechanism by which this mutation is associated to ADH is that VLDL carrying the mutant apo E produces LDLR down-regulation, thereby raising plasma low-density lipoprotein cholesterol levels.

Atherosclerosis progression in patients with autosomal dominant hypercholesterolemia in clinical practice.

BACKGROUND: Autosomal dominant hypercholesterolemias (ADH) are associated with high risk of premature cardiovascular disease (CVD). No data on progression of atherosclerosis in ADH population in clinical practice are available. OBJECTIVE: To investigate atherosclerosis progression in ADH patients and its relationship with CVD risk factors. METHODS: A total of 463 patients, 279 with familial hypercholesterolemia and 184 with familial combined hyperlipidemia, were prospectively followed during a median of 36.5 months. Carotid intima-media thickness (cIMT) was assessed at baseline and at the end of the follow-up by ultrasonography. RESULTS: A total of 259 patients (55.9%) showed cIMT progression and 149 (32.2%) remained within normal age-adjusted cIMT. Baseline cIMT was the variable most inversely associated with cIMT progression (B = -0.313; P < .001). Hypertension, diabetes, and smoking during follow-up were variables positively associated with progression. Patients who began statin treatment during the study period had less progression than former statin users. The 83.7% of ADH with normal baseline cIMT, absence of major CVD risk factors and non-high-density lipoprotein (HDL) cholesterol <190 mg/dL at follow-up remained with normal cIMT at the end of the study. Non-HDL cholesterol concentration reached during the follow-up was associated with cIMT only in subjects with abnormal cIMT at baseline. In this subgroup, cIMT tended to avoid progression with non-HDL cholesterol <130 mg/dL. CONCLUSION: Atherosclerosis progression varies greatly among ADH patients. cIMT progression was inversely related to baseline cIMT and previous use of statins, and positively with age and CVD risk factors during the follow-up. Patients previously treated with statins may not be the preferred candidates for atherosclerosis regression trials. Treatment recommendations in ADH should be based on baseline risk.

[Lipoprotein(a) is associated to atherosclerosis in primary hypercholesterolemia]. / La lipoproteína(a) se asocia a la presencia de arteriosclerosis en pacientes con hipercolesterolemia primaria.

INTRODUCTION: Several studies have suggested that Lp(a) could be a risk factor mainly in hypercholesterolemic patients. METHODS: A total of 909 individuals were selected for this study. 307 were diagnosed of familiar hypercholesterolemia with a pathogenic mutation in LDLR or APOB genes (FH+), 291 of familiar combined hyperlipidemia (FCH) and 311 of familial hypercholesterolemia without a pathogenic mutation in LDLR nor APOB genes (FH-). Main risk factor were studied, included statin treatment. Plasma lipids, Lp(a), HbA1c and C-reactive protein. Intima-media thickness (IMT) of common and bulb carotid in both sides were measured in all subjects. RESULTS: Lp(a) values (median, interquartile range) were 21.9mg/dL (9.24-50.5) in FH+, 22.4mg/dL (6.56-51.6) in FCH and 32.7 (14.6-71.5) in FH- (P<.001). Regression analysis including age, gender, HDL cholesterol, LDL cholesterol corrected for Lp(a), Lp(a), C-reactive protein, packs of cigarettes/day per year, systolic blood pressure and glucose as independent variables, demonstrate that Lp(a) was associated with carotid IMT in FH- subjects. Cardiovascular disease was more frequent in subjects with Lp(a) >50mg/dL (17.9%) than in subjects with Lp(a) <15mg/dL (9.6%), and between 15-50mg/dL (10.1%), and it was concentrated mostly in FH-group (6.7, 11.3, and 23.4% for the groups of Lp(a) <15mg/dL 15-50mg/dL, and >50mg/dL, respectively). CONCLUSIONS: Our results indicate that Lp(a) is associated with atherosclerosis burden especially in subjects with FH- and concentrations of Lp(a)>50mg/dL.

Beneficial effects of omega-3 fatty acids in the proteome of high-density lipoprotein proteome.

BACKGROUND: Omega-3 poly-unsaturated fatty acids (ω-3 PUFAs) have demonstrated to be beneficial in the prevention of cardiovascular disease, however, the mechanisms by which they perform their cardiovascular protection have not been clarified. Intriguingly, some of these protective effects have also been linked to HDL. The hypothesis of this study was that ω-3 PUFAs could modify the protein cargo of HDL particle in a triglyceride non-dependent mode. The objective of the study was to compare the proteome of HDL before and after ω-3 PUFAs supplemented diet. METHODS: A comparative proteomic analysis in 6 smoker subjects HDL before and after a 5 weeks ω-3 PUFAs enriched diet has been performed. RESULTS: Among the altered proteins, clusterin, paraoxonase, and apoAI were found to increase, while fibronectin, α-1-antitrypsin, complement C1r subcomponent and complement factor H decreased after diet supplementation with ω-3 PUFAs. Immunodetection assays confirmed these results. The up-regulated proteins are related to anti-oxidant, anti-inflammatory and anti-atherosclerotic properties of HDL, while the down-regulated proteins are related to regulation of complement activation and acute phase response. CONCLUSIONS: Despite the low number of subjects included in the study, our findings demonstrate that ω-3 PUFAs supplementation modifies lipoprotein containing apoAI (LpAI) proteome and suggest that these protein changes improve the functionality of the particle.