Cerebrotendinous xanthomatosis, a metabolic disease with different neurological signs: two case reports.

Cerebrotendinous xanthomatosis (CTX) is an autosomal recessive inborn error of bile acids synthesis and lipid accumulation caused by a deficiency of the mitochondrial cytochrome P450 sterol 27-hydroxylase enzyme encoded by CYP27A1. Pathogenic variants in CYP27A1 cause elevated cholestanol levels in the body, which leads to a variable clinical presentation that often includes cataracts, intellectual disability, neurological features, tendon xanthomas, and chronic diarrhea. Herein we describe the cases of two unrelated adult CTX patients. Case 1 is a patient with neurological dysfunction, including moderate intellectual disability, cataract of right eye, and xanthomas; Case 2 is a patient with tendon xanthomas without neurological symptoms. Plasma sterols profile obtained from both cases showed higher levels of cholestanol and cholesterol biosynthetic precursors compared to unaffected subjects. Case 1 and Case 2 were homozygous for the c.1263 + 5G > T (p.Leu396Profs29X) and c.1435C > G (p.Arg479Gly) pathogenic variants, respectively, in the CYP27A1 gene. Interestingly, for the first time, Case 2 variant has been identified in a homozygous state. Our results highlight that the sterol profile and genetic analyses are essential to make the diagnosis of CTX and to exclude other dyslipidemias.

Association of USF1 and APOA5 polymorphisms with familial combined hyperlipidemia in an Italian population.

BACKGROUND: Familial combined hyperlipidemia (FCH) is a polygenic and multifactorial disease characterized by a variable phenotype showing increased levels of triglycerides and/or cholesterol. The aim of this study was to identify single nucleotides (SNPs) in lipid-related genes associated with FCH. METHODS AND RESULTS: Twenty SNPs in lipid-related genes were studied in 142 control subjects and 165 FCH patients after excluding patients with mutations in the LDLR gene and patients with the E2/E2 genotype of APOE. In particular, we studied the 9996G > A (rs2073658) and 11235C > T (rs3737787) variants in the Upstream Stimulatory Factor 1 gene (USF1), and the -1131T > C (rs662799) and S19W (rs3135506) variants in the Apolipoprotein A-V gene (APOA5). We found that the frequencies of these variants differed between patients and controls and that are associated with different lipid profiles. At multivariate logistic regression SNP S19W in APOA5 remained significantly associated with FCH independently of age, sex, BMI, cholesterol and triglycerides. CONCLUSIONS: Our results show that the USF1 and APOA5 polymorphisms are associated with FCH and that the S19W SNP in the APOA5 gene is associated to the disease independently of total cholesterol, triglycerides and BMI. However, more extensive studies including other SNPs such as rs2516839 in USF1, are required.

Effects of baked products enriched with n-3 fatty acids, folates, ß-glucans, and tocopherol in patients with mild mixed hyperlipidemia.

OBJECTIVE: To assess whether a diet containing foods enriched with ß-glucans (3.6 g/d), folic acid (1600 µg/d), long-chain (800 mg/d) and short-chain (400 mg/d) n-3 fatty acids, and tocopherols (120 mg/d) is able to modulate positively the cardiovascular risk profile in people at slightly increased cardiovascular risk. METHODS: Sixteen subjects with mild plasma lipid abnormalities were studied according to a randomized crossover design. After a 2-week run-in period, they followed a diet containing baked products enriched with active nutrients (active diet) or a diet containing the same products but without active nutrients (control diet) for 1 month and then crossed over to the other diet. At the end of each period, a test meal of the same composition as the corresponding diet was administered, and plasma samples were obtained before and for 6 hours after the meal. Hunger and satiety were evaluated by the visual analog scale at fasting and after the meal. RESULTS: Fasting plasma triglycerides were significantly lower after the active versus the control diet (1.56 ± 0.18 vs 1.74 ± 0.16 mmol/l, p < 0.05), as was the postprandial level of chylomicron triglycerides and the insulin peak (p < 0.05). The active diet also reduced fasting homocysteine (8 ± 0.6 vs 10 ± 0.8 µmol/l, p < 0.05) and the feeling of hunger at the fifth and sixth hour (p < 0.05). CONCLUSIONS: Baked functional products enriched with n-3 fatty acids, folates, ß-glucans, and tocopherols within the context of a balanced diet lower fasting and postprandial plasma triglycerides, fasting homocysteinemia, and the postprandial insulin peak. They induce a greater feeling of satiety with possible beneficial implications on energy intake.

An improved method on stimulated T-lymphocytes to functionally characterize novel and known LDLR mutations.

The main causes of familial hypercholesterolemia (FH) are mutations in LDL receptor (LDLR) gene. Functional studies are necessary to demonstrate the LDLR function impairment caused by mutations and would be useful as a diagnostic tool if they allow discrimination between FH patients and controls. In order to identify the best method to detect LDLR activity, we compared continuous Epstein-Barr virus (EBV)-transformed B-lymphocytes and mitogen stimulated T-lymphocytes. In addition, we characterized both novel and known mutations in the LDLR gene. T-lymphocytes and EBV-transformed B-lymphocytes were obtained from peripheral blood of 24 FH patients and 24 control subjects. Functional assays were performed by incubation with fluorescent LDL followed by flow cytometry analysis. Residual LDLR activity was calculated normalizing fluorescence for the mean fluorescence of controls. With stimulated T-lymphocytes we obtained a better discrimination capacity between controls and FH patients compared with EBV-transformed B-lymphocytes as demonstrated by receiver operating characteristic (ROC) curve analysis (the areas under the curve are 1.000 and 0.984 respectively; P < 0.0001 both). The characterization of LDLR activity through T-lymphocytes is more simple and faster than the use of EBV-transformed B-lymphocytes and allows a complete discrimination between controls and FH patients. Therefore the evaluation of residual LDLR activity could be helpful not only for mutation characterization but also for diagnostic purposes.

Association between Lp(a) and small dense LDL in menopausal women without metabolic syndrome.

Background: Lipoprotein (a) (Lp [a]) is associated with premature atherosclerosis in menopausal women without metabolic syndrome (MS). MS is the main confounder in the relationship between Lp(a) and atherosclerosis in menopausal women. We have evaluated the relationship between Lp(a) and small dense-low density lipoprotein (sd-LDL) in 228 menopausal women participating to Progetto Atena. Methods: Lp(a) was measured and LDL particle separation was performed: mean LDL diameter and LDL score (% of sd-LDL) particles calculated. Results: Women without MS and elevated Lp(a) have increased number of sd-LDL (p < .05) and higher LDL score compared with those below the median of the studied population (p < .05). The association between Lp(a) and sd-LDL was evaluated taking into account different adjustment models. Women with elevated levels of Lp(a) show the following OR of having a small LDL diameter (in the lowest quartile): 1.02, p = .003; adjusted for age; 1.02, p = .002; adjusted for age, and triglycerides, or a high LDL score (in the highest quartile): 1.02, p = .006; adjusted for age; 1.02, p = .002; adjusted for age and triglycerides. Conclusions: In this group of menopausal women without MS, the independent association of Lp(a) with sd-LDL might explain at least in part the association of Lp(a) with premature atherosclerosis.

Tumor necrosis factor-alpha is a marker of familial combined hyperlipidemia, independently of metabolic syndrome.

It is unclear whether an association between familial combined hyperlipidemia (FCHL) and inflammatory markers exists, independently of age, sex, body weight, insulin resistance, and metabolic syndrome. Serum concentrations of soluble vascular cell adhesion molecule-1 (sVCAM-1), monocyte chemoattractant protein 1, interleukin 6, tumor necrosis factor-alpha (TNF-alpha), and high-sensitive C-reactive protein were determined in 135 probands with FCHL and in 146 normolipidemic, normotensive, normoglycemic healthy subjects. Insulin resistance was evaluated using homeostasis model assessment (HOMA). All inflammatory parameters, except interleukin 6, were significantly higher in FCHL according to medians or mean comparisons. After adjustment for age, sex, body mass index, and HOMA, only TNF-alpha remained an independent predictor of FCHL status by binary logistic regression (odds ratio [OR], 1.19; 95% confidence interval [CI], 1.07-1.31; P = .001). In particular, elevated levels of TNF-alpha (above the 90th and 95th percentiles of the value observed in the control group, 9.6 and 9.8 pg/mL, respectively) were independent predictors of FCHL status: for TNF-alpha above the 90th percentile, OR was 7.91 (95% CI, 3.27-19.13; P < .001), and for TNF-alpha above 95th percentile, OR was 13.08 (95% CI, 4.60-37.15; P < .0001). The independent role of TNF-alpha as predictor of FCHL status was confirmed after adjustment for components of the metabolic syndrome (P = .007 and P = .003, for TNF-alpha values above 90th and 95th percentiles, respectively). In conclusion, among the inflammatory markers most commonly measured, only TNF-alpha was associated with FCHL independently of age, sex, body mass index, and HOMA. The association of TNF-alpha with FCHL was also independent of the metabolic syndrome.

Small dense LDL particles and metabolic syndrome in a sample of middle-aged women. Findings from Progetto Atena.

Metabolic Syndrome (MS) is highly prevalent in the general population. Recently, small dense LDL (sd-LDL) particles have been considered a risk marker in MS diagnosis. We analyzed cross-sectionally the association between sd-LDL and MS in a population-based sample of 210 middle-aged southern Italian women; among them 86 participants had MS (prevalence 40.9%). LDL particle separation was performed by Lipoprint System: seven LDL subfractions were obtained and LDL score (% of sd-LDL particles) calculated. Women with the MS diagnosis had significantly higher LDL score as compared to participants without MS diagnosis (median 0 vs. 3.6, p<0.001 by Mann Whitney). The univariate analysis showed a positive and significant association between MS diagnosis (OR 4.80; 95% CI 2.29-10.18; p<0.001 for MS diagnosis) and some MS components Triglycerides (TG), HDL Cholesterol (HDL-C), (OR 14.82; 95% CI 5.24-41.88; p<0.001 for Ln TG); (OR 0.92; 95% CI 0.89-0.95; p<0.001 for HDL-C) and LDL score. Apo B and insulin levels were also positively related to the presence of sd-LDL (OR 31.56; 95% CI 5.58-178.29; p<0.001 for apo B); (OR 1.07; 95% CI 1.00-1.15; p<0.05 for insulin). After controlling for age, insulin and apo B, MS diagnosis (OR 4.0; 95% CI 1.76-9.09; p<0.001 for MS diagnosis) and MS components (TG, HDL-C) (OR 4.41; 95% CI 1.22-15.87; p=0.023 for Ln TG); (OR 0.94; 95% CI 0.89-0.98; p=0.009 for HDL-C) remained significantly associated with high LDL score (upper quintile). Our results suggest that sd-LDL particles could be a valuable marker for diagnosis and severity of the MS. Future prospective epidemiological studies are envisaged to explore the specific contribution of this marker on cardiovascular risk. LDL size measurement could be an useful tool for identifying a subsample patients with prominent lipoprotein abnormality, within the large population with the MS diagnosis, and who are candidates for intensive lipid-lowering interventions.

Causative mutations and premature cardiovascular disease in patients with heterozygous familial hypercholesterolaemia.

Background Familial hypercholesterolemia is a common autosomal dominant disease, caused by mutations leading to elevated low-density lipoprotein (LDL) cholesterol and, if untreated, to premature cardiovascular disease. Methods Patients (young adults with a family history of hypercholesterolaemia or premature cardiovascular disease) with LDL cholesterol concentration ≥4.9 mmol/l, after excluding Familial Combined Hyperlipidaemia, were evaluated for causative mutations, Dutch Lipid Clinic Network score calculation and non-invasive ultrasound examination of carotid arteries. Results Of the 263 patients, 210 were heterozygotes for LDL receptor ( LDLR) mutations, four had APOB gene mutations, one PCSK9 gene mutation, while 48 had no evidence of mutations. Among 194 unrelated index cases 149 had mutations (77%). Among patients with LDLR mutations ( n = 145), there were five compound heterozygotes, 75 patients with null mutations and 65 with missense mutations. As many as 178 patients underwent a follow-up and treatment (statin ± ezetimibe), achieving a mean reduction of 49% in LDL cholesterol, with 21% of patients reaching the LDL goal of 2.6 mmol/l. In a multivariate analysis, carotid plaques, at ultrasound examination, were associated with the presence of genetic mutation ( p = 0.001), LDL cholesterol ( p < 0.001), Dutch Lipid Clinic Network score ( p < 0.001), independently of age, gender, smoking habits and systolic blood pressure. The presence of carotid plaque ( p = 0.017), LDL cholesterol ( p < 0.003), Dutch Lipid Clinic Network score ( p < 0.001) were independently associated with premature cardiovascular disease. Conclusions We identified patients with causative mutations in 82% of the cases under study. In addition to LDL cholesterol and Dutch Lipid Clinic Network score, carotid plaques in ultrasound evaluation provide direct evidence of premature vascular disease and are associated with high risk for cardiovascular events.

Association between Lp (a) and atherosclerosis in menopausal women without metabolic syndrome.

AIM: The association between Lipoprotein (a) (Lp [a]) and common carotid intima media thickness (IMT) has been evaluated in 222 menopausal women. MATERIAL & METHODS: Lp (a) and IMT were measured, carotid ultrasound examination (B-Mode imaging) was performed and mean max IMT was calculated. RESULTS: Lp (a) was significantly lower in women with metabolic syndrome (MS). In a multivariate analysis Lp (a) showed the following odds ratio (OR; all p < 0.05) of having common carotid IMT (≥1.30 mm): 1.03, adjusted for age, low-density lipoprotein cholesterol (LDL) and waist circumference; 1.02, adjusted for age LDL, homeostatic assessment model (HOMA). In women without MS, after controlling for age, LDL and waist circumference, we found the following OR for increased IMT (≥1.30; OR: 1.03; for Lp [a]); 1.02 adjusted for age, LDL and HOMA (all p < 0.05). In women with MS these relationships were not statistically significant. CONCLUSION: Lp (a) gives additional information in the risk assessment for atherosclerotic cardiovascular disease, especially in menopausal women without MS.

Effects of Armolipid Plus on small dense LDL particles in a sample of patients affected by familial combined hyperlipidemia.

AIM: The aim of this study was to test small dense LDL changes with Armolipid Plus treatment in patients with familial combined hyperlipidemia (FCHL). METHODS: After 4 weeks, 30 patients with FCHL were included in an 8-week, randomized, double-blind study and were taking, in addition to the standard diet, either placebo or Armolipid Plus. RESULTS: The placebo group showed no statistically significant differences in the studied parameters; instead, in the Armolipid Plus group, statistically significant reduction differences were detected in BMI (p = 0.010), LDL score (p = 0.035) and an increase in mean LDL particle diameter (p = 0.040). CONCLUSION: The combination of a standard diet with Armolipid Plus is able to reduce LDL score and increase LDL particle diameter in a group of FCHL after 8 weeks of treatment.

Identification and functional characterization of LDLR mutations in familial hypercholesterolemia patients from Southern Italy.

OBJECTIVE: Autosomal dominant hypercholesterolemias are due to defects in the LDL receptor (LDLR) gene, in the apolipoprotein B-100 gene or in the proprotein convertase subtilisin/kexin type 9 gene. The aim of this study was to identify and functionally characterize mutations in the LDLR gene that account for most cases of familial hypercholesterolemia (FH). METHODS: We enrolled 56 unrelated patients from Southern Italy with a clinical diagnosis of FH. The mutation screening was performed by direct sequencing of the promoter and the 18 exons of the LDLR gene and by multiplex ligation-dependent probe amplification (MLPA) analysis to search for large rearrangements. RESULTS AND CONCLUSION: We found 5 new mutations, the causative role of which was demonstrated by functional characterization performed by quantification of fluorescent LDL uptake in EBV-transformed B lymphocytes. These results enlarge the spectrum of FH-causative LDLR mutations. Lastly, screening for large rearrangements is highly recommended for the genetic diagnosis of FH.

Efficacy and safety of rosuvastatin in the management of dyslipidemia.

Rosuvastatin is a synthetic statin that represents an advance in the pharmacologic and clinical properties of statins. Relative to other statins, rosuvastatin possesses a greater number of binding interactions with HMG-CoA reductase and has a high affinity for the active site of the enzyme. As with other statins, serious adverse effects with rosuvastatin therapy are uncommon and primarily involve effects on the liver and skeletal muscle. The risk increases with increasing dosages and coadministration with other drugs interacting with the same metabolic pathway. The degree of LDL reduction is important to achieve the treatment goals suggested by international guidelines. Among the most potent statins, rosuvastatin is capable of getting the majority of patients to their LDL cholesterol goals. In addition, rosuvastatin has been found effective in reducing small-dense LDL, C-reactive protein and in increasing HDL cholesterol levels. Controlled clinical trials using vascular end-points have been performed. In particular, a study demonstrated that rosuvastatin therapy could slow progression and/or cause regression of carotid intima-media thickness over 2 years in middle-aged individuals with a low Framingham risk score (FRS) and mild to moderate subclinical atherosclerosis. A primary prevention study (JUPITER) was stopped before the programmed end of the study, because of excess benefit for high-risk individuals receiving rosuvastatin treatment. It is suggested that pronounced LDL reduction, in association with significant HDL cholesterol increase, are the bases of a marked preventive action of rosuvastatin. The results from JUPITER support the use of rosuvastatin for primary cardiovascular prevention, in overweight men and women, with near to normal LDL cholesterol and high CRP. There is now evidence of benefit from rosuvastatin treatment for a wide segment of the general population at intermediate cardiovascular risk. In absolute numbers, this segment represents the main source of cardiovascular events: on the basis of JUPITER results, it is expected that treatment target and potential candidates to statin therapy will be reevaluated and redefined.

Small dense low-density lipoprotein in familial combined hyperlipidemia: Independent of metabolic syndrome and related to history of cardiovascular events.

INTRODUCTION: It is unclear whether small dense low-density lipoprotein (sdLDL) are associated with familial combined hyperlipidemia (FCHL), independently of the metabolic syndrome (MS). It is also unclear whether sdLDL are related to history of cardiovascular (CVD) events in FCHL patients, independently of MS. PATIENTS AND METHODS: Serum levels of sdLDL, expressed as percentage of total LDL cholesterol (LDL score), were determined in 137 probands with FCHL and in 133 normolipidemic, normotensive, normoglycemic healthy subjects. RESULTS: In binary logistic regression age- and gender-adjusted LDL score values above the 90th and 95th percentiles of the values in the control group (10.23 and 13.11%, respectively) were found to be significant predictors of FCHL status, independently of MS diagnosis (p=0.007 and p<0.0001, respectively). Values of the LDL score above the 90th and the 95th percentile of the control group resulted to be significantly related to FCHL status, even after adjustment for the components of MS (p=0.006 and p=0.001, respectively). Among FCHL patients, values of the LDL score above 95th percentile of the values in the control group were found to be significantly related to personal and/or family history of CVD events, independently of age, gender, total cholesterol, apolipoprotein (apo) B, and MS status (p=0.016). The same significant relationship was found adjusting for all components of MS (p=0.034). CONCLUSIONS: High concentrations of sdLDL are highly specific markers of FCHL, independently of concomitant MS. In FCHL patients high levels of sdLDL are related to history of CVD events, independently of MS, total cholesterol and apo B.