Clinical characterization and detection of subclinical atherosclerosis in subjects with extreme hyperalphalipoproteinemia. / Caracterización clínica y detección de arteriosclerosis subclínica en sujetos con hiperalfalipoproteinemia extrema.

INTRODUCTION AND OBJECTIVES: The association between HDL cholesterol (HDL-C) levels and death from cardiovascular disease follows a U-shaped pattern, increasing at the extremes. The objective of the study was to characterize a sample of subjects with extreme hyperalphalipoproteinemia (HAE). MATERIAL AND METHODS: 53 cases with HAE were recruited, 24 women (HDL-C>135mg/ dL) and 29 men (HDL-C>116mg/ dL). A detailed medical history was taken and questionnaires on adherence to the Mediterranean diet and physical activity were collected. Carotid ultrasounds were performed to detect the presence of suclinical atherosclerosis. RESULTS: The most prevalent cardiovascular risk factor (CVRF) was dyslipidemia (64%) with no significant differences between men and women, unlike hypertension (21% in women, versus 55% in men, p=0.01) and others CVRF, for example, diabetes. 7% of the series had previous cardiovascular disease, women had higher LDL cholesterol (p=0.002) and HDL-C than men (without significant differences). Plaque was detected in 53% of cases, being more prevalent in men. Patients with plaque were older, drank more alcohol and smoked more (p<0.05). CONCLUSIONS: Men had a higher prevalence of CVRF than women, except for dyslipidemia. Subclinical atherosclerosis occurred in more than half of the series. Age, alcohol consumption and smoking were independently associated with the presence of plaque, however, our data do not show a significant influence of HDL-C levels.

Early detection of severe hypertriglyceridemia using teleconsultation in a clinical laboratory setting.

BACKGROUND: Teleconsultation in the context of clinical laboratories is a valuable tool for the early detection of dyslipidemia and prevention of cardiovascular risk. Here, we describe a patient who was referred to the Lipid Unit of the Virgen Macarena Hospital due to an alert for severe hypertriglyceridemia through its teleconsultation program. CASE PRESENTATION: A comprehensive clinical and biochemical study of the patient was carried out, and genetic testing was performed on the patient and his family. The proband and his family showed mild to severe hypertriglyceridemia and various secondary factors, together with a genetic background associated with a triglyceride-raising effect. CONCLUSION: This extensive study has identified a family at high risk of cardiovascular disease and acute pancreatitis. These findings can help maximize lifestyle changes and improve the clinical management of their dyslipidemia.

Un caso de hipocolesterolemia a estudio / A case of hypocholesterolemia under study

Las hipocolesterolemias primarias (o hipobetalipoproteinemias) constituyen un trastorno infrecuente del metabolismo de las lipoproteínas que pueden obedecer a una predisposición poligénica o a una enfermedad monogénica. Entre estas, es posible diferenciar entre formas sintomáticas y asintomáticas, en las que, en ausencia de causas secundarias, la sospecha clínica inicial son concentraciones plasmáticas de ApoB por debajo del percentil 5 de la distribución por edad y sexo. En esta nota clínica describimos del diagnóstico diferencial de un caso de hipocolesterolemia asintomática. Estudiamos los datos clínicos de la paciente índice, así como su perfil lipídico y el de los familiares junto con los datos clínicos de estos que son relevantes para realizar el diagnóstico diferencial. Se realizó un estudio genético como prueba diagnóstica. El diagnóstico diferencial realizado sugirió una hipobetalipoproteinemia heterocigota por variantes de pérdida de función en PCSK9. La prueba diagnóstica puso de manifiesto, en la paciente índice, la presencia de una variante de cambio de pauta de lectura en PCSK9, en heterocigosis, de origen materno. Las concentraciones plasmáticas de colesterol de LDL y PCSK9 de la paciente y los familiares, fueron compatibles con la segregación de dicha variante. En conclusión, la prueba diagnóstica realizada permitió confirmar el diagnóstico de sospecha en el caso estudiado de hipobetalipoproteinemia familiar asintomática a causa de una variante de pérdida de función en el gen PCSK9. (AU)

Primary hypocholesterolemia (or hypobetalipoproteinemia) is a rare disorder of lipoprotein metabolism that may be due to a polygenic predisposition or a monogenic disease. Among these, it is possible to differentiate between symptomatic and asymptomatic forms, in which, in the absence of secondary causes, the initial clinical suspicion is plasma ApoB levels below the 5th percentile of the distribution by age and sex. Here we describe the differential diagnosis of a case of asymptomatic hypocholesterolemia. We studied proband's clinical data, the lipid profile of the proband and her relatives and the clinical data of the family relevant to carry out the differential diagnosis. We performed a genetic study as the diagnostic test. The information obtained from the differential diagnosis suggested a heterozygous hypobetalipoproteinemia due to PCSK9 loss-of-function variants. The diagnostic test revealed, in the proband, the presence of a heterozygous PCSK9 frame-shift variant of a maternal origin. Plasma levels of LDL cholesterol and PCSK9 of the patient and her relatives were compatible with the segregation of the variant revealed. In conclusion, the diagnostic test performed confirmed the suspected diagnosis of the proband as asymptomatic familial hypobetalipoproteinemia due to a loss-of-function variant in the PCSK9 gene. (AU)

A case of hypocholesterolemia under study. / Un caso de hipocolesterolemia a estudio.

Primary hypocholesterolemia (or hypobetalipoproteinemia) is a rare disorder of lipoprotein metabolism that may be due to a polygenic predisposition or a monogenic disease. Among these, it is possible to differentiate between symptomatic and asymptomatic forms, in which, in the absence of secondary causes, the initial clinical suspicion is plasma ApoB levels below the 5th percentile of the distribution by age and sex. Here we describe the differential diagnosis of a case of asymptomatic hypocholesterolemia. We studied proband's clinical data, the lipid profile of the proband and her relatives and the clinical data of the family relevant to carry out the differential diagnosis. We performed a genetic study as the diagnostic test. The information obtained from the differential diagnosis suggested a heterozygous hypobetalipoproteinemia due to PCSK9 loss-of-function variants. The diagnostic test revealed, in the proband, the presence of a heterozygous PCSK9 frame-shift variant of a maternal origin. Plasma levels of LDL cholesterol and PCSK9 of the patient and her relatives were compatible with the segregation of the variant revealed. In conclusion, the diagnostic test performed confirmed the suspected diagnosis of the proband as asymptomatic familial hypobetalipoproteinemia due to a loss-of-function variant in the PCSK9 gene.

Role of lipoprotein lipase activity measurement in the diagnosis of familial chylomicronemia syndrome.

BACKGROUND: Activity assays for lipoprotein lipase (LPL) are not standardised for use in clinical settings. OBJECTIVE: This study sought to define and validate a cut-off points based on a ROC curve for the diagnosis of patients with familial chylomicronemia syndrome (FCS). We also evaluated the role of LPL activity in a comprehensive FCS diagnostic workflow. METHODS: A derivation cohort (including an FCS group (n = 9), a multifactorial chylomicronemia syndrome (MCS) group (n = 11)), and an external validation cohort (including an FCS group (n = 5), a MCS group (n = 23) and a normo-triglyceridemic (NTG) group (n = 14)), were studied. FCS patients were previously diagnosed by the presence of biallelic pathogenic genetic variants in the LPL and GPIHBP1 genes. LPL activity was also measured. Clinical and anthropometric data were recorded, and serum lipids and lipoproteins were measured. Sensitivity, specificity and cut-offs for LPL activity were obtained from a ROC curve and externally validated. RESULTS: All post-heparin plasma LPL activity in the FCS patients were below 25.1 mU/mL, that was cut-off with best performance. There was no overlap in the LPL activity distributions between the FCS and MCS groups, conversely to the FCS and NTG groups. CONCLUSION: We conclude that, in addition to genetic testing, LPL activity in subjects with severe hypertriglyceridemia is a reliable criterium in the diagnosis of FCS when using a cut-off of 25.1 mU/mL (25% of the mean LPL activity in the validation MCS group). We do not recommend the NTG patient based cut-off values due to low sensitivity.

Evaluation of the chylomicron-TG to VLDL-TG ratio for type I hyperlipoproteinemia diagnostic.

BACKGROUND: The aim of this study is to confirm the diagnostic performance of the Chylomicron to very low-density lipoproteins triglycerides (CM/VLDL-TG) ratio, the triglycerides to cholesterol ratio (TG/TC) and a dichotomic rule including the tryglycerides to apolipoprotein B (TG/APOB) ratio for the presence of Type I hyperlipoproteinemia (HPLI) in patients with severe hypertriglyceridemia (sHTG) that were at high risk for familial chylomicronemia syndrome (FCS). METHODS: Two cohorts (derivation and validation) of patients with sHTG were included in the study. Anthropometric, clinical, biochemical and genetic data were obtained. The CM/VLDL-TG, TG/TC and TG/APOB ratios were calculated. Finally, a diagnostic performance study was developed to establish sensitivity, specificity and cut-offs by a ROC curve analysis in the derivation cohort as well as agreement and predictive values in the validation cohort. RESULTS: Patients with FCS in both cohorts showed an earlier presence in pancreatitis, greater number of acute pancreatitis episodes and lower BMI. FCS patients also showed higher ratios of CM/VLDL-TG, TG/TC and TG/APOB ratios, whereas their HDL-C, LDL-C and APOB levels were lower than in non-FCS patients. Sensitivity and agreement were low for both the TG/TC and TG/APOB ratios, although predictive values were good. The CM/VLDL-TG ratio showed greatest sensitivity, specificity, agreement and predictive values for cut-off of 3.8 and 4.5. CONCLUSIONS: Our results suggest that in subjects at high risk of FCS a total serum TG/TC ratio or TG/APOB ratio are feasible to initially screen for HLPI; however, a CM/VLDL-TG ratio ≥4.5 is a better diagnostic criterion for HPLI.

Genetic variants in the LPL and GPIHBP1 genes, in patients with severe hypertriglyceridaemia, detected with high resolution melting analysis.

INTRODUCTION: Pathogenic variants in lipoprotein lipase (LPL) and glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1) have been described in patients with severe hypertriglyceridaemia. We aimed to optimise high resolution melting (HRM) assays to detect the presence of functional variants in these genes. METHODS: One hundred and sixteen patients with severe hypertriglyceridaemia were studied. HRM assays were optimised to scan exons and splice junctions in LPL and GPIHBP1. Sanger sequencing was the reference method. Next-generation-sequencing (NGS) was performed in five patients, including one with Familial Chylomicronemia syndrome (FCS). RESULTS: We identified 15 different variants in LPL and 6 in GPIHBP1. The variants revealed with NGS were also detected with HRM, including a rare premature stop codon in LPL (p.Trp421*) and two LPL pathogenic variants in the patient with FCS (p.His80Arg + p.Gly215Glu). Having multiple functional variant alleles was associated with pancreatitis onset at younger ages and higher baseline triglycerides. CONCLUSIONS: Our HRM assays detected the presence of functional gene variants that were confirmed with Sanger and NGS sequencing. The presence of multiple functional variant alleles was associated with differences in the clinical profile. Therefore, these assays represent a reliable, cost-effective tool that can be used to complement the NGS approach for gene scanning.

Molecular basis of the familial chylomicronemia syndrome in patients from the National Dyslipidemia Registry of the Spanish Atherosclerosis Society.

BACKGROUND: Familial chylomicronemia syndrome (FCS) is an extremely rare lipoprotein disorder caused by mutations in at least 5 genes of the lipoprotein lipase (LPL) complex. OBJECTIVE: This work shows the molecular analysis of patients diagnosed with FCS, who attended the Spanish Arteriosclerosis Society lipid units and were included in the National Dyslipidemia Registry. METHODS: Among the 238 patients registered with severe hypertriglyceridemia (fasting triglycerides >1000 mg/dL), 26 were diagnosed with FCS as they had confirmed postheparin plasma LPL activity deficiency and/or homozygosity for loss-of-function mutations in LPL, GPIHBP1, APOC2, LMF1, or Apolipoprotein A5 (APOA5). RESULTS: Among the 26 FCS cases, 23 had mutations in the homozygous state: 19 in LPL and 4 in the GPIHBP1 gene. The molecular analysis revealed 3 novel mutations: 2 in LPL, in 2 unrelated patients (c.312delA; p.Asp105Thrfs*66 and c.629A>G; p.His210Arg), and 1 in GPHIBP1 in a third patient (c.502delC; p.Leu168Serfs*83). These 3 patients had confirmed lack of LPL activity. Three additional patients with confirmed LPL activity deficiency were heterozygous carriers of mutations in the genes analyzed. Among these, we found 2 novel mutations in APOA5 (c.50-1G>A and c.326_327insC; p.Tyr110Leufs*158). CONCLUSION: We have identified 5 novel pathogenic mutations: 2 in LPL, 1 in GPIHBP1, and 2 in the APOA5 gene. The genetic defaults accounting for the LPL activity deficiency of 23 of them have been clearly identified and 3 patients, who harbored mutations in heterozygosity, were diagnosed based on LPL activity deficiency, which raises the question of the involvement of new genes in the manifestation of FCS.

The Effects of Parenteral K1 Administration in Pseudoxanthoma Elasticum Patients Versus Controls. A Pilot Study.

INTRODUCTION: Pseudoxanthoma elasticum (PXE) is a rare disease caused by mutations in the ABCC6 gene. Vitamin K1 is involved in the posttranslational carboxylation of some proteins related to inhibition of the calcification process. Our aim was to investigate, in patients affected by PXE, baseline levels of vitamin K1-dependent proteins and -metabolites and whether parenteral administration of phytomenadione was effective in modulating their levels. METHODS: We included eight PXE patients with typical clinical symptoms (skin, retina, and vascular calcification) and two ABCC6 causative mutations; 13 clinically unaffected first-degree patients' relatives (9 carrying one ABCC6 mutation and 4 non-carriers). We assessed urinary vitamin K1 metabolites and serum Glu- and Gla-OC, Gas6 and undercaboxylated prothrombin (PIVKA-II), at baseline and after 1 and 6 weeks after a single intramuscular injection of 10 mg vitamin K1. RESULTS: Comparison of PXE patients, heterozygous, and non-carriers revealed differences in baseline levels of serum MK-4 and of urinary vitamin K metabolites. The response to phytomenadione administration on vitamin K-dependent proteins was similar in all groups. CONCLUSION: The physiological axis between vitamin K1 and vitamin K-dependent proteins is preserved; however, differences in the concentration of vitamin K metabolites and of MK-4 suggest that vitamin K1 metabolism/catabolism could be altered in PXE patients.

Novel mutations in the GPIHBP1 gene identified in 2 patients with recurrent acute pancreatitis.

BACKGROUND: Glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1) has been demonstrated to be essential for the in vivo function of lipoprotein lipase (LPL), the major triglyceride (TG)-hydrolyzing enzyme involved in the intravascular lipolysis of TG-rich lipoproteins. Recently, loss-of-function mutations of GPIHBP1 have been reported as the cause of type I hyperlipoproteinemia in several patients. METHODS: Two unrelated patients were referred to our Lipid Units because of a severe hypertriglyceridemia and recurrent pancreatitis. We measured LPL activity in postheparin plasma and serum ApoCII and sequenced LPL, APOC2, and GPIHBP1. RESULTS: The 2 patients exhibited very low LPL activity not associated with mutations in LPL gene or with ApoCII deficiency. The sequence of GPIHBP1 revealed 2 novel point mutations. One patient (proband 1) was found to be homozygous for a C>A transversion in exon 3 resulting in the conversion of threonine to lysine at position 80 (p.Thr80Lys). The other patient (proband 2) was found to be homozygous for a G>T transversion in the third base of the ATG translation initiation codon in exon 1, resulting in the conversion of methionine to isoleucine (p.Met1Ile). CONCLUSION: In conclusion, we have identified 2 novel GPIHBP1 missense mutations in 2 unrelated patients as the cause of their severe hypertriglyceridemia.

Alzheimer's like brain changes correlate with low adiponectin plasma levels in type 2 diabetic patients.

AIM: To study the association between adiponectin plasma levels, and gray matter brain volume and cerebral glucose metabolism in a group of type 2 diabetes patients. METHODS: We studied 25 type 2 diabetes patients and 25 age- and gender-matched healthy control participants. Biochemical analysis and structural cerebral magnetic resonance imaging, including voxel-based morphometry and (18)-fluorodeoxyglucose positron emission tomography, were performed. The gray matter volumes and metabolism changes were analyzed using statistical parametric mapping (SPM8). RESULTS: Lower levels of adiponectin correlated with a lower gray matter volume in temporal regions and with reduced cerebral glucose metabolism in temporal regions (p<0.001), adjusted for age, gender, education, and the presence of at least one epsilon 4 allele for the apolipoprotein E (APOEε4 genotype). CONCLUSIONS: Positive correlations between adiponectin plasma levels and both gray matter volume and cerebral glucose metabolism were found, predominantly in temporal regions, as in Alzheimer's disease. Adiponectin might be a biomarker for the cognitive decline associated with type 2 diabetic patients.

Acuerdo intra-interobservador en las pruebas Minimental State Examination (MMSE) y Montreal Cognitive Assessment (MoCA test) aplicados por personal en entrenamiento / Intra and interrater reliability of the Minimental State Exmination (MMSE) and Montréal Cognitive Assessment (MoCA test) applied by health personnel in training

Introducción: en el proceso del diagnóstico neuropsicológico, los instrumentos de tamizaje cognitivo, son una herramienta útil en la identificación de cambios mentales del sujeto, en momentos puntuales o a través del tiempo. Su uso se fundamenta en el análisis psicométrico. Objetivo: determinar el acuerdo inter e intra-observador en el MoCA test y el MMSE, aplicado por profesores y estudiantes en procesos de entrenamiento de tamización cognitiva. Materiales y métodos: a los estudiantes y profesores en entrenamiento en la puntuación del MoCA test y el MMSE, se les presentó un video en dos sesiones, con un intervalo de 5 meses, mostrando el desempeño de dos adultos mayores, respondiendo el MoCA test y el MMSE, previo consentimiento informado. Se compararon los puntajes dados en las dos sesiones por los sujetos en entrenamiento, con los de ellos mismos (intra-observador), usando el coeficiente de concordancia y correlación de Lin(rho) y con los del grupo restante (inter-observador) usando el coeficiente de correlación intra-clase (ICC). Resultados: participaron 46 evaluadores. Se encontró alta confiabilidad inter-observador para el MoCA (ICC=0.86), pero baja para el MMSE (ICC=0.24) y baja confiabilidad intra-observador tanto para el MoCA (rho paciente 1=0.012 y rho paciente 2=0.152) como para el MMSE (rho paciente 1=0.008 y rho paciente 2=0.012). Aunque los puntajes difirieron, las clasificaciones diagnósticas realizadas por los evaluadores fueron similares a las del patrón de oro. Conclusión: la correcta aplicación del test, requiere varios entrenamientos, y aunque hubo pocas diferencias entre los puntajes, los errores cuando se está cerca del punto de corte propuesto, aumentan el riesgo de sesgo.

Introduction: The instruments for screening cognitive functions, applied to subjects in clinical settings and research, are useful for determining if this person has any trouble in cognition or show changes in the time. The usefulness of these instruments is defined with the evaluation of their psychometrics properties. Objective: This study allows to determine the intra and inter-observer agreement, when the MoCA test and MMSE were applied by a group in training process Materials and methods: The study group who attended two training sessions, with an interval of 5 months, scored the MoCA test and MMSE, from two patients which were filmed responding the tests, previous informed consent signature. We compared how close were the scores of participants among themselves by concordance correlation coefficient of Lin (rho) and with those given from the others by intra-class correlation coefficients (ICC). Results: In total, 46 participants were included. Intra-rater reliability was high for MoCA test (ICC = 0.86), but it was poor for MMSE (ICC=0.24). Inter-rater was poor for MoCA test (rho patient 1= 0.012, rho patient 2= 0.152) and MMSE (rho patient 1 = 0.008, rho patient 2 = 0.012). Although the scores between participants and gold standard were different, the diagnoses were similar. Conclusion:The correct scoring of the test, requires several trainings to clinical and research groups, and although they can be found few differences between scores applied by non-expert personnel, if the scores mistakenly given, are close to the cut-of point proposed for each test, the bias increases.

Cognitive dysfunctions in middle-aged type 2 diabetic patients and neuroimaging correlations: a cross-sectional study.

BACKGROUND/OBJECTIVE: The aim was to assess the neuropsychological performance of a group of middle-aged patients with well-controlled type 2 diabetes mellitus (T2DM) and to examine whether the neuropsychological deficits correlate with structural and functional brain alterations. METHODS: We compared 25 subjects with T2DM aged 45-65 years with 25 control participants matched for age, gender, and educational level. The neuropsychological battery was designed to examine executive functions, attention, information processing speed, and verbal memory. Severity of depression was assessed using the Hamilton Depression Rating Scale and cardiovascular risk factors were assessed using the Framingham Cardiovascular Risk Profile Score. The presence of at least one APOEε4 allele was determined. Reduced gray matter density was analyzed using voxel-based morphometry and brain glucose metabolic changes were assessed by 18FDG-PET. RESULTS: T2DM subjects had significantly lower scores than subjects without T2DM in the Trail-making Test B (p < 0.004), Color-Word Stroop test (p < 0.005), Semantic Fluency (p < 0.006), Digit-Symbol modalities test (p < 0.02), Text Recall from the Wechsler Memory Scale (p < 0.0001), Rey-Osterrieth Complex Figure-copy (p < 0.004), and delayed reproduction (p < 0.03). Worse executive functions and memory functioning correlated predominantly with less gray matter density and reduced glucose metabolism in the orbital and prefrontal cortex, temporal (middle gyrus, parahippocampus and uncus), and cerebellum regions (p < 0.001). CONCLUSIONS: T2DM subjects presented cognitive dysfunctions compared with controls. Clinical-neuroimaging correlations corresponded to brain changes (reduced gray matter density and glucose metabolism) mainly in fronto-temporal areas.

Triglyceride levels and apolipoprotein E polymorphism in patients with acute pancreatitis.

BACKGROUND: Hypertriglyceridemia is an unusual cause of acute pancreatitis and sometimes considered to be an epiphenomenon. This study aimed to investigate the clinical and analytical features and the APOE genotypes in patients with acute pancreatitis and severe hypertriglyceridemia. METHODS: We undertook a one-year, prospective study of patients with acute pancreatitis whose first laboratory analysis on admission to the emergency department included measurement of serum triglycerides. The APOE genotype was determined and the patients answered an established questionnaire within the first 24 hours concerning their alcohol consumption, the presence of co-morbidities and any medications being taken. The patients' progression, etiological diagnosis, hospital stay and clinical and radiological severity were all recorded. RESULTS: Hypertriglyceridemia was responsible for 7 of 133 cases of pancreatitis (5%); the remaining cases were of biliary (53%), idiopathic (26%), alcoholic (11%) or other (5%) origin. Compared with these remaining cases, the patients with hypertriglyceridemia were significantly younger, had more relapses, and more often had diabetes mellitus. They usually consumed alcohol or consumed it excessively on the days before admission. Also, the ε4 allele of the APOE gene was more common in this group (P<0.05). CONCLUSION: One of 20 episodes of acute pancreatitis is caused by hypertriglyceridemia and it is linked to genetic (ε4 allele) and comorbid factors such as diabetes and, especially, alcohol consumption.

Análisis de la influencia de polimorfismos en APOE, APOA5, LPL, LIPC y CETP sobre los niveles de triglicéridos en población laboral malagueña / Analysis of the influence of polymorphisms in the APOE, APOA5, LPL, LIPC and CETP (Spain)

Introducción: Los triglicéridos se consideran un factor independiente de riesgo vascular. La influencia, por separado, de polimorfismos en genes como APOE, APOA5, LPL, LIPC y CETP sobre dichos niveles está descrita, por lo que resulta de interés su análisis conjunto y el estudio de interacciones con factores ambientales. Métodos: Se han genotipado en 1.825 sujetos (80% varones, edad media 36 años) procedentes del estudio ICARIA, el polimorfismo de APOE, 2 variantes de APOA5 (S19W y -1131 T/C), 5 deLPL (D9N, N291S, PvuII, HindIII y S447X), 1 de LIPC (-250G/A) y 1 de CETP (TaqI ) mediante PCR-restricción y ensayos TaqMan. El efecto conjunto de las variantes se ha analizado mediante regresión lineal con la variable triglicéridos transformada logarítmicamente y corrigiendo porcovariables. Las interacciones se han explorado mediante contrastes múltiples. Resultados: El alelo 4 de APOE, los polimorfismos de APOA5 S19W y -1131T/C y las variantes de LPL, D9N y N291S mostraron un efecto elevador de triglicéridos significativo e independiente. Los polimorfismos HindIII y S447X de LPL se asociaron significativamente con una reducción de los niveles de TG. Las variantes PvuII (LPL), -250G/A (LIPC) y TaqI (CETP) no mostraron asociaciones significativas. Se encontró una tendencia estadística (p=0,048) para la interacción entre obesidad abdominal (perímetro de cintura >102 cm en hombres; >88 cm en mujeres) y elalelo APOE- 4 (AU)

Introduction: Triglyceride levels are considered to be an independent vascular risk factor. The influence of polymorphisms in genes such as APOE, APOA5, LPL, LIPC and CETP on these levels has been separately described. The aim of the present study was to analyze the combined effects of these polymorphisms and their interaction with environmental factors. Methods: We genotyped the APOE polymorphism, two variants of APOA5 (S19W and -1131 T/C),five of LPL (D9N, N291S, PvuII, HindIII and S447X), one of LIPC (-250G/A) and one of CETP (TaqI )by polymerase chain reaction-restriction and TaqMan assays in 1825 subjects (80% male, meanage 36 years) from the ICARIA study. The combined effect of the variants was analyzed by linear regression with the log-transformed triglyceride variable and adjustment for covariates. The interactions were explored by multiple comparisons. Results: The 4 allele of APOE, the APOA5 polymorphisms S19W and -1131T/C and the LPL variants D9N and N291S independently and significantly increased triglyceride levels. The HindIII and S447X LPL polymorphisms were significantly associated with lower triglyceride levels. The PvuII (LPL), -250G/A (LIPC) and TaqI (CETP) variants showed no significant associations. There was a statistical trend (p = 0.048) for an interaction between abdominal obesity (waist circumference >102 cm in men and >88 cm in women) and the APOE- 4 allele. Conclusions: Our study shows the influence of the APOE- 4 allele, the S19W and -1131T/Cpolymorphisms of APOA5 and the LPL-D9N, N291S, HindIII and S447X variants on triglyceride levels and suggests that the effect of the 4 allele could by modulated by interaction with abdominal obesity (AU)

Additive effects of LPL, APOA5 and APOE variant combinations on triglyceride levels and hypertriglyceridemia: results of the ICARIA genetic sub-study.

BACKGROUND: Hypertriglyceridemia (HTG) is a well-established independent risk factor for cardiovascular disease and the influence of several genetic variants in genes related with triglyceride (TG) metabolism has been described, including LPL, APOA5 and APOE. The combined analysis of these polymorphisms could produce clinically meaningful complementary information. METHODS: A subgroup of the ICARIA study comprising 1825 Spanish subjects (80% men, mean age 36 years) was genotyped for the LPL-HindIII (rs320), S447X (rs328), D9N (rs1801177) and N291S (rs268) polymorphisms, the APOA5-S19W (rs3135506) and -1131T/C (rs662799) variants, and the APOE polymorphism (rs429358; rs7412) using PCR and restriction analysis and TaqMan assays. We used regression analyses to examine their combined effects on TG levels (with the log-transformed variable) and the association of variant combinations with TG levels and hypertriglyceridemia (TG > or = 1.69 mmol/L), including the covariates: gender, age, waist circumference, blood glucose, blood pressure, smoking and alcohol consumption. RESULTS: We found a significant lowering effect of the LPL-HindIII and S447X polymorphisms (p < 0.0001). In addition, the D9N, N291S, S19W and -1131T/C variants and the APOE-epsilon4 allele were significantly associated with an independent additive TG-raising effect (p < 0.05, p < 0.01, p < 0.001, p < 0.0001 and p < 0.001, respectively). Grouping individuals according to the presence of TG-lowering or TG-raising polymorphisms showed significant differences in TG levels (p < 0.0001), with the lowest levels exhibited by carriers of two lowering variants (10.2% reduction in TG geometric mean with respect to individuals who were homozygous for the frequent alleles of all the variants), and the highest levels in carriers of raising combinations (25.1% mean TG increase). Thus, carrying two lowering variants was protective against HTG (OR = 0.62; 95% CI, 0.39-0.98; p = 0.042) and having one single raising polymorphism (OR = 1.20; 95% CI, 1.39-2.87; p < 0.001) or more (2 or 3 raising variants; OR = 2.90; 95% CI, 1.56-5.41; p < 0.001) were associated with HTG. CONCLUSION: Our results showed a significant independent additive effect on TG levels of the LPL polymorphisms HindIII, S447X, D9N and N291S; the S19W and -1131T/C variants of APOA5, and the epsilon4 allele of APOE in our study population. Moreover, some of the variant combinations studied were significantly associated with the absence or the presence of hypertriglyceridemia.

Lipoprotein lipase activity and mass, apolipoprotein C-II mass and polymorphisms of apolipoproteins E and A5 in subjects with prior acute hypertriglyceridaemic pancreatitis.

BACKGROUND: Severe hypertriglyceridaemia due to chylomicronemia may trigger an acute pancreatitis. However, the basic underlying mechanism is usually not well understood. We decided to analyze some proteins involved in the catabolism of triglyceride-rich lipoproteins in patients with severe hypertriglyceridaemia. METHODS: Twenty-four survivors of acute hypertriglyceridaemic pancreatitis (cases) and 31 patients with severe hypertriglyceridaemia (controls) were included. Clinical and anthropometrical data, chylomicronaemia, lipoprotein profile, postheparin lipoprotein lipase mass and activity, hepatic lipase activity, apolipoprotein C II and CIII mass, apo E and A5 polymorphisms were assessed. RESULTS: Only five cases were found to have LPL mass and activity deficiency, all of them thin and having the first episode in childhood. No cases had apolipoprotein CII deficiency. No significant differences were found between the non-deficient LPL cases and the controls in terms of obesity, diabetes, alcohol consumption, drug therapy, gender distribution, evidence of fasting chylomicronaemia, lipid levels, LPL activity and mass, hepatic lipase activity, CII and CIII mass or apo E polymorphisms. However, the SNP S19W of apo A5 tended to be more prevalent in cases than controls (40% vs. 23%, NS). CONCLUSION: Primary defects in LPL and C-II are rare in survivors of acute hypertriglyceridaemic pancreatitis; lipase activity measurements should be restricted to those having their first episode during childhood.

Respuesta posprandial de la apolipoproteína B-48 y del perfil lipídico en pacientes con diabetes mellitus tipo 2 / Post-prandial response of apolipoprotein B-48 and the lipid profile in patients with type-2 diabetes mellitus

Introducción. En el presente trabajo, hemos evaluado las diferencias en la respuesta posprandial, incluidos en ésta los valores de la apolipoproteína (apo) B-48 y el perfil lipídico, entre varones y mujeres, en una población de pacientes con diabetes mellitus tipo 2 (DM2). También se analizó la relación entre la apo B-48 y determinadas variables antropométricas, glucídicas y lipídicas implicadas en la aparición y desarrollo de la enfermedad diabética. Pacientes y métodos. Se recogieron los datos antropométricos y clínicos de 50 pacientes con DM2 y se tomaron muestras de 12 h de ayunas y 4 h después de un desayuno mixto. A las muestras de plasma, en ayunas de 12 h, por centrifugación, se les cuantificó hemoglobina glucosilada, índice HOMA-IR, fenotipo de las lipoproteínas de baja densidad, apo A-1, apo B-100, perfil lipídico y apo B-48. Se cuantificó también el perfil lipídico y los valores de apo B-48 de las muestras posprandiales. Resultados. Ambos sexos difirieron únicamente en los valores de colesterol unido a lipoproteínas de alta densidad (p < 0,05). En el total de pacientes, se observó un incremento posprandial significativo de triglicéridos y apo B-48, siendo en esta última variable de mayor magnitud (18 frente a 58%). Los valores de apo B-48, en ayunas y posprandiales, correlacionaron únicamente con los triglicéridos en ayunas y posprandiales (p < 0,05). Conclusiones. Comprobamos que los triglicéridos y la apo B-48, variables que presentan un fuerte incremento posprandial, especialmente en la apo B-48, son similares en ambos sexos y que el principal parámetro asociado con los valores de apo B-48 en estos individuos son los valores de triglicéridos en ayunas y posprandiales (AU)

Introduction. The aim of this study has been to evaluate the postprandial response, including apolipoprotein (apo) B-48 levels and the lipid profile, in men and women with Type 2 Diabetes Mellitus. The relationships between apo B-48 with anthropometric values, fasting and postprandial lipids as well as glucose homeostasis parameters were also analyzed. Patients and methods. Clinic and anthropometric parameter were included from 50 type 2 diabetic patients. 12 h fasting blood samples and 4 h after a mixed breakfast. %HbA1c, HOMA index, LDL phenotype, apo A1 and apo B-100 levels, the lipid profile and apo B-48 levels were measured in fasting plasma. The lipid profile and apo B-48 were also measured in postprandial plasma samples. Results. Both men and women only differed in HDL-C level (p < 0,05). A significant postprandial increase was observed in triglycerides and apo B-48 levels, being in the latter of higher magnitude (18% vs. 58%). Fair correlations between fasting and postprandial apo B-48 and fasting and postprandial triglycerides were observed (p < 0,05). Conclusions. Apo B-48 showed higher postprandial increase than plasma triglycerides, with no difference in men and women. Among several variables analyzed, fasting and postprandial triglycerides were the strongest predictors of fasting and postprandial apo B-48 (AU)

Association of the -250G/A promoter polymorphism of the hepatic lipase gene with the risk of peripheral arterial disease in type 2 diabetic patients.

AIM: This study aimed to investigate the association between a polymorphism in the hepatic lipase (LIPC) gene promoter and the presence of peripheral arterial disease (PAD) in persons with type 2 diabetes. PATIENT AND METHODS: We evaluated 120 type 2 diabetics and identified those with PAD according to the ankle-arm index. The G-250A polymorphisms in the promoter of the LIPC gene were studied by PCR restriction. A logistic regression analysis was performed to determine the association between the rare allele and PAD. RESULTS: The prevalence of PAD was 19%. The frequency of the -250A allele was 0.211 in the group without PAD and 0.395 in the group with PAD (P<.05). Carriers of the -250A allele differed only in the ankle-arm index (0.92+/-0.12 for carriers vs. 1.00+/-0.12 for noncarriers, P<.05), with the difference remaining significant after adjustment for covariates (age; sex; waist-to-hip ratio; body mass index; duration of diabetes; smoking; hypertension; glycated hemoglobin; triglycerides; HDL cholesterol; LDL cholesterol; small, dense LDL cholesterol). Only smoking [odds ratio (OR)=6.93, 95% confidence interval (CI)=2.12-22.69, P=.001] and the -250A allele (OR=2.89, 95% CI=1.07-7.84, P=.036) were significantly associated with vascular disease in the logistic regression analysis. CONCLUSIONS: Patients with type 2 diabetes who are carriers of the rare -250A allele in the promoter of the hepatic lipase gene are susceptible to PAD.