Aortic valve and arterial calcification in patients with familial hypercholesterolemia.

Heterozygous familial hypercholesterolemia (heFH) is an autosomal dominant lipid metabolism disorder. Its prevalence is 1:250-1:300 people in the population. Patients with heFH have an up to 13-fold increased risk of premature coronary artery disease (CAD). If left untreated, men and women with heFH typically develop early CAD before the ages of 55 and 60, respectively. There is evidence that coronary artery calcification (CAC) and aortic valve calcification (AoVC) are more prevalent in FH patients than in the general population. It is documented that CAC and AoVC are predictors of increased risk of cardiovascular morbidity and mortality in heFH patients, like in the general population. However, the etiology and pathogenesis of vascular calcification in FH patients is not well understood. Risk factors for vascular calcification include age, increased levels of atherogenic lipoproteins, Lp(a), increased blood pressure, and inflammation. There are convincing data from clinical studies and animal atherosclerotic mouse models using low-density lipoprotein receptor (LDL-R) knockout mice that the vascular calcification processes in FH are associated with LDL-R mutations, probably partly due to a higher total cholesterol burden of FH subjects. Data from animal models as well as clinical studies indicate that the Wnt/beta-catenin pathway components and LDL receptor-related proteins 5 and 6 (LRP-5/6) might be involved in calcification processes in FH patients. The purpose of the review is to describe the prevalence of coronary and aortic calcification and its risk factors in FH patients. The review covers data about the role of the Wnt/beta-catenin pathway and factors modulating calcification processes.

Targeted sequencing of a gene panel in patients with familial hypercholesterolemia from Southern Poland.

INTRODUCTION: Familial hypercholesterolemia (FH) is an autosomal dominant monogenic lipid metabolism disorder characterized by a significantly elevated level of low­density lipoprotein (LDL) cholesterol and leading to premature ischemic heart disease. FH is caused by mutations in the LDLR, APOB, and PCSK9 genes; however, these mutations account for only about 40% of FH cases. In order to obtain a genetic diagnosis of FH, sequencing of other genes involved in the lipid metabolism might be useful. OBJECTIVES: This study aimed to describe genetic variants in genes associated with FH in a group of patients from the Malopolska province in Southern Poland, using the targeted next generation sequencing (NGS) technology. PATIENTS AND METHODS: The study involved 90 unrelated adults (age range, 18-70 years) with FH diagnosed clinically according to the Simon Broome Register criteria. A custom­designed capture assay and the Illumina MiSeq platform were used. The panel included exons and exon / intron boundaries of known FH­causing genes: LDLR, APOB, and PCSK9, as well as genes previously associated with high cholesterol levels: APOE, ABCG5, ABCG8, LPL, NPC1, LDLRAP1, LIPC, STAP1, and CELSR2. Genetic variants were classified based on in silico predictions and ClinVar reports. RESULTS: We detected 4 patients with variants in the LDLR and APOB genes that had not been previously linked to FH in ClinVar. We also found APOB mutations outside the common LDL receptor-binding region, in exons 26 and 29. Interestingly, we observed a high frequency of pathogenic variants in exon 4 of the APOE gene: rs7412, probably damaging (4 patients) and rs429358, benign (16 patients). CONCLUSIONS: NGS is a useful and reliable method to detect new variants in genes related to FH. In addition, the results enable the detection of FH phenocopies and introduction of appropriate treatment.

Serum PCSK9 Correlates with PTX3 and Apolipoproteins B, A1, and C3 Concentrations in Patients with Type 2 Diabetes.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is involved in the regulation of LDL metabolism. There is evidence that circulating PCSK9 is a cardiovascular risk factor. In this study, we determined factors associated with circulating PCSK9 in a group of patients with type 2 diabetes mellitus (DM2). Material included 116 consecutive patients with DM2 from outpatient diabetes clinic. Circulating PCSK9, PTX3, apolipoprotein (apo) B100, apo B48, and apo C3 levels were determined by ELISA, apo A1 by immunoturbidimetry. The mean (sd) age of patients was 59.1 (11.1) years, the mean (sd) values of serum PCSK9 were 255.4 (106.97) ng/ml. Circulating PCSK9 correlated negatively with age (r = -0.21, p < 0.05) and HbA1c (r = -0.21, p < 0.05) and positively with BMI (r = 0.21, p < 0.05), total cholesterol (r = 0.59), LDL-cholesterol (r = 0.50), triglyceride (r = 0.35), apo B100 (r = 0.43), apo A1 (r = 0.43) (p < 0.001 for all), apo C3 (r = 0.29, p < 0.01), and apo B48 (r = 0.25, p < 0.01) concentration and FLI (r = 0.26, p < 0.01). Strong correlation between PTX3 and PCSK9 levels was observed (r = 0.47, p < 0.001). Multiple stepwise backward regression analysis with PCSK9 as dependent variable revealed that PTX3, apo B100, apo A1, apo B48, and BMI were significantly positive and the presence of NAFLD and HbA1c negatively associated with PCSK9 concentrations. These variables together explain 57% of PCSK9 variability; the strongest relationship was observed between PCSK9 and PTX3 and apo B100. Our results indicate that circulating PCSK9 is significantly associated with inflammation marker PTX3 as well as atherogenic lipids and apolipoproteins C3, B100, and B48, which might be of value in understanding interactions between development of atherosclerosis and inflammatory state in DM2 patients.

Correlates of pentraxin 3 serum concentration in men and women with type 2 diabetes.

Elevated levels of plasma pentraxin 3 (PTX3), a marker of inflammation, are associated with the risk of developing cardiovascular diseases in the general population, as well as in patients with type 2 diabetes (DM2). In this study, we aimed to determine factors associated with PTX3 serum concentrations in men and women with DM2. The study included 116 consecutive patients (67 men and 49 women) with DM2 from an outpatient diabetic clinic. Men were characterised by lower age and higher uric acid, creatinine and bilirubin concentrations and waist/hip ratio than women. In women, low-density lipoprotein cholesterol (LDL-C) levels were higher than in men. In men, median (interquartile range) values of PTX3 concentration were 4.02 (1.99), and in women they were 4.53 (3.31) ng/ml (NS). In men, PTX3 concentrations correlated with total cholesterol (TC), triglycerides, apolipoprotein (Apo) C3, Apo B48, Glc and creatinine levels. In women, PTX3 correlated significantly with TC and LDL-C and Apo B100. Partial regression analysis revealed that after adjusting for age, PTX3 concentrations in men were significantly associated with TC, LDL-C, triglycerides, creatinine, Apo C3 and Apo B48, while in women they were associated with TC, LDL-C and Apo B100. The results could be of importance in sex-specific prevention of vascular complications in DM2 patients.

Serum pentraxin 3 concentration in patients with type 2 diabetes and nonalcoholic fatty liver disease.

INTRODUCTION: Nonalcoholic fatty liver disease (NAFLD) is common in patients with type 2 diabetes (T2D). Pentraxin 3 (PTX3), a marker of inflammation, is a cardiovascular risk factor. OBJECTIVES: We examined clinical and biochemical factors associated with serum PTX3 concentrations in patients with T2D with and without NAFLD. PATIENTS AND METHODS: Serum material was obtained from 116 patients with T2D (mean age, 59.1 years), including 79 patients with NAFLD. RESULTS: Median (interquartile range) PTX3 level was 4.264 (2.293) ng/ml in patients with and 3.773 (3.223) ng/ml in patients without NAFLD (P = 0.93). In the whole group, PTX3 level was associated with total cholesterol, low­density lipoprotein cholesterol (LDL­C), apolipoprotein (apo) B100, apo C3, triglyceride (TG) concentrations, and waist circumference after adjustment for age and gender. As indicated by partial regression coefficient b, increase of independent variable LDL­C by 1 mmol/l was associated with the rise of PTX3 by 1.2017 ng/ml, increase of apo B100 by 1 mg/dl with the rise of PTX3 by 1.0051 ng/ml, and increase of apo C3 by 1 µg/dl with the rise of PTX3 by 1.0012 ng/ml. In patients with T2D with NAFLD, total cholesterol, LDL­C, TG, apo C3, and apo B100 were associated with PTX3. Associations of PTX3 with apolipoproteins were observed only in the NAFLD group. CONCLUSIONS: Reported associations of PTX3 level add new insight into possible mechanisms of its atherogenic actions.

The genetic spectrum of familial hypercholesterolemia in south-eastern Poland.

BACKGROUND: Familial hypercholesterolemia (FH) is a common autosomal dominant disorder with a frequency of 1 in 200 to 500 in most European populations. Mutations in LDLR, APOB and PCSK9 genes are known to cause FH. In this study, we analyzed the genetic spectrum of the disease in the understudied Polish population. MATERIALS AND METHODS: 161 unrelated subjects with a clinical diagnosis of FH from the south-eastern region of Poland were recruited. High resolution melt and direct sequencing of PCR products were used to screen 18 exons of LDLR, a region of exon 26 in the APOB gene and exon 7 of PCSK9. Multiplex ligation-dependent probe amplification (MLPA) was performed to detect gross deletions and insertions in LDLR. Genotypes of six LDL-C raising SNPs were used for a polygenic gene score calculation. RESULTS: We found 39 different pathogenic mutations in the LDLR gene with 10 of them being novel. 13 (8%) individuals carried the p.Arg3527Gln mutation in APOB, and overall the detection rate was 43.4%. Of the patients where no mutation could be found, 53 (84.1%) had a gene score in the top three quartiles of the healthy comparison group suggesting that they have a polygenic cause for their high cholesterol. CONCLUSIONS: These results confirm the genetic heterogeneity of FH in Poland, which should be considered when designing a diagnostic strategy in the country. As in the UK, in the majority of patients where no mutation can be found, there is likely to be a polygenic cause of their high cholesterol level.

[Determinants of nonalcoholic fatty liver disease in men and women with type 2 diabetes]. / Determinanty niealkoholowego stluszczenia watroby u mezczyzn i kobiet z cukrzyca typu 2.

Nonalcoholic fatty liver disease (NAFLD) is recognized in 20-30% of general population but among the people with impaired glucose metabolism this percentage is about 70-90%. The aim of this study is to assess the determinants of NAFLD with respect to patients' gender. We examined 180 patients, 73 women and 107 men. Increased body mass index (BMI), waist circumference above the norm are the determinants of NAFLD irrespectively to gender. Besides it has been observed that in the women group the increase of HDL-cholesterol by 1 mmol/l decreases the chances of NAFLD occurrence by 90%.

Nonalcoholic fatty liver disease is associated with low HDL cholesterol and coronary angioplasty in patients with type 2 diabetes.

BACKGROUND: There is evidence that nonalcoholic fatty liver disease (NAFLD) is associated with increased cardiovascular risk. In this study we examined factors associated with the presence of NAFLD and the prevalence of macroangiopathy in patients with type 2 diabetes. MATERIAL AND METHODS: Subjects were 101 consecutive patients with type 2 diabetes: 72 with NAFLD and 29 free of NAFLD. NAFLD was diagnosed by ultrasonography. Serum lipids were measured enzymatically and glycated hemoglobin HbA1c was measured by HPLC. RESULTS: The mean age of patients was 53.1 ± 10.4 in the NAFLD group and 44.9 ± 10.9 years in patients without NAFLD (p<0.001). The mean duration of diabetes was 10 ± 6.3 years in patients with NAFLD and 15.1 ± 7.8 years in those without NAFLD (p<0.001). Mean values of glycated hemoglobin A1c were similar in both groups. Patients with NAFLD were characterized by a significantly higher prevalence of coronary angioplasty (20.8% vs. 0%, p=0.008). Overweight and obesity were observed in a higher percentage of patients with NAFLD (p<0.001). Patients with NAFLD were characterized by significantly higher values of alanine transaminase (p=0.033), and lower serum concentrations of HDL-cholesterol (p<0.001) and creatinine (p=0.034). Logistic regression analysis (p<0.001) revealed that NAFLD was positively associated with waist circumference above normal (women >80 cm, men >94 cm) (p=0.0083) and alanine transaminase activity (p=0.0164), and negatively with creatinine concentration (p=0.0226). In a second logistic regression model (p<0.001), waist circumference (p<0.007) and total cholesterol (p<0.008) were positive predictors, while HDL-C (p<0.003) was a negative predictor of NAFLD. CONCLUSIONS: The results of the study suggest that NAFLD is associated with visceral obesity and low HDL-cholesterol in patients with type 2 diabetes.

Intima-media thickness correlates with features of metabolic syndrome in young people with a clinical diagnosis of familial hypercholesterolaemia.

BACKGROUND: Familial hypercholesterolaemia (FH) is a monogenic lipid metabolism disorder characterised by markedly elevated serum low-density lipoprotein (LDL) cholesterol level due to a mutation in the LDL receptor gene. Clinical features of FH include premature atherosclerosis and coronary artery disease. AIM: To explore associations between noninvasive markers of atherosclerosis including intima-media thickness (IMT) and pulse wave velocity (PWV) and blood lipids, blood pressure (BP) and obesity in a group of young patients with FH. METHODS: Study population included 36 patients aged < 35 years with the diagnosis of FH based on the Simon Broome Register criteria, and their 49 relatives who comprised the control group free of FH. RESULTS: Mean IMT values were higher in FH patients than controls (0.60 ± 0.19 vs. 0.53 ± 0.07 mm, respectively, p < 0.05).Mean body mass index (BMI) and waist circumference were similar in patients and controls. The prevalence of carotid atherosclerotic plaques was significantly higher among FH patients (n = 6) than in controls (n = 1) (21.4% vs. 2.6%, p = 0.012). Arterial hypertension was present in 27.8% of patients with FH and 16.3% of subjects in the control group. Systolic blood pressure (SBP) in FH patients correlated significantly with age (r = 0.35), BMI (r = 0.48) and waist circumference (r = 0.47), and diastolic blood pressure (DBP) correlated with BMI (r = 0.42) and waist circumference (r = 0.41). PWV correlated significantly with age (r = 0.44), SBP (r = 0.63) and DBP (r = 0.52). We did not find any correlations between IMT and serum lipids, BP or obesity indices in FH patients. CONCLUSIONS: Our findings show a higher rate of arterial hypertension in young FH patients compared to their relatives free of FH, with significant associations between BP and indices of obesity and arterial stiffness. Intensive lipid lowering and antihypertensive therapy along with a reduction in central fat may be considered a mandatory treatment strategy in young FH patients to prevent atherosclerosis and increased arterial stiffness.

Management of familial heterozygous hypercholesterolemia: Position Paper of the Polish Lipid Expert Forum.

Heterozygous familial hypercholesterolemia (HFH) affects on average 1 in 500 individuals in European countries, and it is estimated that HeFH in Poland may affect more than 80,000 people. Cardiovascular mortality in individuals with FH between 20 and 39 years of age is 100 times higher than in the general population. HFH is a relatively common lipid disorder, but usually still remaining undiagnosed and untreated. A very high risk of cardiovascular diseases and a shortened lifespan in patients with this condition require early diagnosis and intensive treatment. The aim of the position paper was to present the importance and scale of this problem in Poland, which has not been raised enough so far, as well as the recommendations of diagnosis, treatment and prevention methods.

[Nonalcoholic fatty liver disease as a risk factor of macroangiopahty in patients with type 2 diabetes]. / Niealkoholowe stluszczenie watroby jako czynnik ryzyka makroangiopatii u chorych z cukrzyca typu 2.

Nonalcoholic fatty liver disease (NAFLD) is recognized in 20-30% of general population but among the people with impaired glucose metabolism is about 70-90%. There is increasing number publications that show strong association between NAFLD, metabolic syndrome and insulin resistance as risk factors of cardiovascular complication. Gens PNPLAL3 NCAN, LYPAL1 and GCKR that have been linked to lipid metabolism disorders or impaired glucose metabolism can also contribute to development of NAFLD. The reduction of body mass and of known risk factors of atherosclerosis and restriction of simple carbohydrates in diet contribute to regression of NAFLD.

A novel mutation (Cys308Phe) of the LDL receptor gene in families from the South-Eastern part of Poland.

The purpose of this investigation was to characterize a new mutation in the LDL-receptor (LDLR) gene in three families with clinically diagnosed familial hypercholesterolemia (FH) from the South-Eastern part of Poland. Mutational screening with exon by exon sequencing analysis was performed in all probands. The novel mutation c986G>T (Cys308Phe) in the exon 7 of LDLR gene was found in three apparently unrelated probands with FH. Analysis of the receptor activity of peripheral blood lymphocytes by binding and uptake of DiL-LDL showed a significant reduction (by 24% versus healthy control) of the fluorescent label in the lymphocytes of patients heterozygous for this mutation. Concentrations of serum LDL-C in probands before treatment were between 9.5 and 10.5 mmol/l. All patients had corneal arcus and tendon xanthoma. Clinically, families were characterized by premature coronary artery disease. This mutation occurred relatively frequently in our group of patients with FH, but this could be explained by a founder effect since we demonstrated their common ancestors.

Corticosteroid treatment of kidney disease in a patient with familial lecithin-cholesterol acyltransferase deficiency.

Familial lecithin-cholesterol acyltransferase (LCAT) deficiency (FLD) is a rare genetic disorder of lipid metabolism, characterised by low plasma HDL cholesterol, proteinuria, haemolytic anaemia and corneal opacities. Usually renal disease progresses during the third decade of life to renal failure; however the pathogenesis of renal disease is not well understood. In this study we describe treatment of renal disease in two siblings with FLD. The proband WX at the age of 31 years presented proteinuria and ankle oedema during her third pregnancy. Diagnosis of FLD was based on a renal biopsy with characteristic serpiginous fibrillar deposits under electron microscopy, markedly decreased HDL cholesterol, esterified cholesterol levels and LCAT activity, confirmed by molecular analysis. After 3 years her proteinuria increased and she received an ACE inhibitor to which she responded well. During further increases of proteinuria she additionally received methylprednisolone and her proteinuria decreased. This long-term observation indicates the efficacy of corticosteroids and renin-angiotensin-aldosterone system blockers in the treatment of proteinuria in patients with FLD. The results suggest the role of inflammatory processes as well as dyslipidemia in the pathogenesis of glomerular disorders in LCAT-deficient patients.