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Cystatin C is an amyloidogenic protein found together with beta-amyloid in cerebral arteriolar walls of both patients with Alzheimer's Disease (AD) and conghopilic amyloid angiopathy. Several findings implicate cystatin C in the pathogenesis of vascular diseases. Recent genetic association studies proposed cystatin C gene (CST3) as a susceptibility factor for AD, although other reports did not replicate this finding. We conducted a case-control study including 192 probable AD cases and 192 age- and sex-matched controls to test the association between CST3 and AD. Possible interaction between CST3 and age at onset of AD or apolipoprotein E (APOE) was also examined. No significant differences in CST3 genotype or allele frequencies between cases and controls was observed, while the risk of AD increased in subjects carrying the APOE epsilon4 allele (OR 3.5, 95% CI [2.1-5.9]). There was no interaction between CST3 with age or APOE. Our findings do not support a role of CST3 gene in Italian sporadic AD.

Background: Cystatin C is the most abundant protease inhibitor in the plasma. Low plasma levels have been found in patients with aortic aneurysms and they seem correlated with the extension of the aortic lesions in early aneurysms detected by ultrasonography., Methods: In this study, plasma levels of cystatin C have been investigated in patients with acute myocardial infarction (AMI), unstable angina and controls. The effect on plasma levels of the G73A polymorphism of the CST3 gene has been also evaluated., Results: Patients with acute myocardial infarction showed significantly lower levels of cystatin C compared to unstable angina and controls, but levels were nearly normal in a week after the acute event. The genotype distribution of the G73A polymorphism was not different among the groups. Nevertheless, cystatin C levels decreased proportionally with the number of A alleles. Cystatin C levels were positively correlated with age, triglyceride/HDL cholesterol ratio and creatinine, and negatively with HDL cholesterol and the number of A alleles. All variables, but not HDL cholesterol, were independently correlated in a multivariate analysis., Conclusions: Cystatin C is decreased in acute myocardial infarction. It is still not clear whether lower cystatin C levels are causally linked to the acute event or just represent a negative acute phase response. The CST3 gene G73A polymorphism functionally affects cystatin C plasma levels.

Introduction: Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive disorder of cholesterol biosynthesis, resulting from deficient 7-dehydrocholesterol reductase (3beta-hydroxysterol Delta7-reductase) activity, the enzyme responsible for conversion of 7-dehydrocholesterol to cholesterol. SLOS is most common among people of European descent, with a reported incidence of 1 per 20,000-60,000 newborns, depending on the diagnostic criteria and the reference population. More than 80 different mutations have been identified in several hundred patients. In Italy, SLOS appears to be a rare condition, probably because of underdiagnosis., Method: We analyzed by direct sequencing the 7-dehydrocholesterol reductase gene (DHCR7) in a Sicilian patient with Smith-Lemli-Opitz syndrome and his parents in order to characterize the molecular defect., Results: The molecular analysis of the coding exons and the intron-exon boundaries of the DHCR7 gene demonstrated the presence of two missense mutations: a novel mutation (I251N) and a known mutation (E288K) responsible in a compound heterozygous state for a severe form of SLOS., Conclusion: The present study describes a Sicilian patient, a carrier of a novel mutation of the DHCR7 gene (I251N), which is responsible in a compound heterozygous state for a severe form of SLOS.

Objective: Chronic constipation in children can be linked to cow's milk intolerance (CMI) but the existence of a food intolerance-dependent proctitis is still debated. The aim of this study was to evaluate the histologic data in patients with food intolerance-related constipation., Material and Methods: Fifty-two consecutive patients (22 M, median age 4 years) with chronic constipation unresponsive to common treatment were enrolled. All patients were put on a cow's milk-free diet for 4 weeks and those uncured on this diet underwent a subsequent 4-week period of oligoantigenic diet. In the patients cured on elimination diet, a subsequent double-blind food challenge was performed to confirm the diagnosis of food intolerance. At entry to the study, routine hemato-chemical and immunologic assays, rectoscopy, and histologic study of the rectal mucosa were performed. In the patients cured on elimination diet, rectal histology was repeated when they were cured., Results: Twenty-four patients were found to be suffering from CMI and 6 from multiple food intolerance. These patients had a normal stool frequency on elimination diet, while constipation reappeared on food challenge. The condition of the remaining 22 patients did not improve on elimination diet. The patients with food intolerance showed a significantly higher frequency of erosions of the mucosa, number of intraepithelial lymphocytes and eosinophils, and number of eosinophils in the lamina propria. Study of the rectal mucus gel layer showed that the food-intolerant patients had a significantly lower thickness than the other subjects studied. In the food intolerant patients, histologic abnormalities disappeared on elimination diet, when the patients were well., Conclusions: Food intolerance-related constipation is characterized by proctitis with eosinophil infiltrate of the rectal mucosa. A reduced mucus gel layer can be considered a contributory factor in the pathogenesis of the constipation.

Beta-2-glycoprotein I (beta(2)GPI) is mainly produced by the liver and is found in plasma partially associated to lipoproteins. Although various properties have been attributed to this protein, its physiological role remains still unclear. We investigated its expression in cultured liver cells and in regenerating liver. Expression studies in HepG2 cells demonstrate that beta(2)GPI mRNA is regulated in a cell cycle-dependent manner, with very low expression in low cycling conditions and increasing levels in proliferating cells. p21 WAF-dependent growth arrest, induced by butyrate treatment, down-regulate beta(2)GPI mRNA levels. Immunolocalization in normal rat liver shows a non-homogeneous pattern, being mainly present in the centrolobular area; post-hepatectomy regenerating rat liver is uniformly immunostained and mitotic elements show the highest protein expression. Albumin gene expression, studies as control liver specific product, was not affected by sodium butyrate induced growth arrest. As previously reported for endothelial cells, beta(2)GPI behaves as survival factor for HepG2 cells: when increasing amounts of the protein (10-50 microg) have been added to serum deficient cultured liver cells a progressive reduced cell loss was observed. In conclusion, the present data demonstrate that beta(2)GPI gene expression is strictly related to the proliferative status of hepatic cells and that this protein could play a role in maintaining liver cells vitality when exposed to different stress factors such as regeneration after partial hepatectomy or growth factors depletion.

Objective: We investigated the possible causes of diabetes in a young child who presented with hyperglycemia associated with severe hypertriglyceridemia (>166 mmol/l), hypercholesterolemia (>38 mmol/l) and fasting chilomicrons., Results: The patient did not have any of the HLA and autoantibody markers typically associated with type 1 diabetes. A glucose clamp failed to demonstrate insulin resistance (peripheral glucose utilization rate (M)=4.3 mg/kg per min) and there was no family history of type 2 diabetes or maturity onset diabetes in youth. Both fasting and stimulated C-peptide levels, including those in response to i.v. glucagon, were below the limit of detection. This is consistent with loss of beta-cell function. The family history did not reveal the existence of relatives with lipid abnormalities, coronary heart disease, and pancreatitis. We did not find any abnormality of plasma apoCII, lipoproteinlipase and hepatic lipase activities. The patients had a epsilon3/epsilon3 apoE genotype and she rapidly cleared an oral fat load after normalization of plasma lipids., Conclusions: The mild hyperglycemia seems an unlikely explanation for both the severe hypertriglyceridemia and chylomicronemia. A more plausible explanation is transient lipoproteinlipase deficiency. This rare condition, occasionally associated with a high-fat diet, could have caused the rapid and dramatic hypertriglyceridemia observed in this patient, which in turn might have led to the beta-cell destruction by direct lipid toxicity.

CD surface molecules mediates cell activation and signaling. In particular, CD14 on blood monocytes mediate monocyte/macrophage activation by lipopolysaccharide. Lipopolysaccharide and its receptor, CD14, have been implicated in atherogenesis. It has been recently shown that a C(-260)T polymorphism in the promoter of the CD14 receptor may be a risk factor for coronary artery disease. Recently this association has been questioned because no increased risk was found with the T allele, even in the homozygous state. In the present study we investigated a possible association between the C(-260)T polymorphism in the CD14 promoter and acute myocardial infarction. Two hundred and thrteen patients with and acute myocardial infarction 213 healthy controls were included in the study. Genotype frequencies of the C(-260)T polymorphism in the CD14 promoter were determined by polimerase chain reaction and the amplified product was cleaved with HaeIII. The frequency of the T allele was not significantly different in patients compared with controls. In this study we were not able to detect differences of frequency of the allele T (-260) in the promoter of the CD14 receptor gene in survivors of myocardial infarction and controls.

Background and Aims: Type III hyperlipoproteinemia, or dysbetalipoproteinemia, is commonly associated with apolipoprotein E2 homozygosity (Cys112, Cys158). Apo E2-Christchurch (Arg136-->Ser), a rare mutation of the Apo E gene, located in the receptor-binding domain of the protein, has been found to be associated in the vast majority of cases of dysbetalipoproteinemia., Methods and Results: This is the first report of two Italian kindreds carrying the Arg136-->Ser mutation. One family is a four-generation kindred from Genoa (Liguria, Italy) with a high rate of mortality due to coronary artery disease: the proband was a 51-year-old woman with previous myocardial infarction and residual angina, severe carotid atherosclerosis, peripheral arterial vascular disease and arterial hypertension. The other family was identified in Palermo (Sicily, Italy): the proband was an overweight 62-year-old man with a mixed form of hyperlipidemia. The mutation, which was identified by means of Apo E genotyping followed by direct sequencing, co-segregated with the same haplotype in the two families., Conclusions: The family histories and clinical examinations of these subjects clearly show that the Apo E Arg136-->Ser variant fully expresses a type III phenotype in association with a second allele coding for Apo E2, and only partially in association with a second allele coding for Apo E4.

We describe a Sicilian family presenting a recessive form of hypercholesterolemia harboring a mutation of the autosomal recessive hypercholesterolemia (ARH) gene. In two of the three sibs, a 26-year-old male and a 22-year-old female, a severe hypercholesterolemia was diagnosed with very high levels of plasma cholesterol (15.9 and 12.2 mmol/l, respectively); tendon xanthomatas and xanthelasms were present and in the male proband was documented a diffuse coronary atherosclerotic disease with a rapid and fatal progression. Both the parents had normal or slightly increased levels of plasma cholesterol. All causes of secondary hypercholesterolemia were ruled out as well as an involvement of the LDL receptor or apoB genes. Beta-Sitosterol plasma levels were in the normal range. Cultured fibroblasts from skin biopsy from parents and the two probands displayed a normal ability to bind and degrade 125I-LDL. Direct sequencing of ARH gene demonstrated the presence of a 432insA mutation in homozygosis in the two probands; parents were heterozygotes for the same mutation. This mutation is the first report of a mutation of the ARH gene responsible for recessive forms of hypercholesterolemia in Sicily.

Background: The predominance of small, dense low-density lipoprotein (LDL) particles ('LDL phenotype B') has been associated with a three-fold increased risk of myocardial infarction, but the feasibility of the identification of small, dense LDL as independent predictors of coronary artery disease risk in population studies remains questioned. Design We evaluated the LDL peak particle size and its relation with other established risk factors for coronary heart disease in a group of 156 randomized subjects living on the Mediterranean island of Ustica (71 males and 85 women, range of age 20-69 years), representing approximately 30% of the total population., Results: The prevalence of LDL phenotype B subjects was low (approximately 15% in both men and women) and there was a clear trend for both genders in reducing the LDL peak particle size with age. Moreover, LDL phenotype B subjects had higher BMI values, prevalence of diabetes and plasma triglyceride (TG) levels and lower plasma HDL-C concentrations in comparison with LDL phenotype A individuals; in a multivariate analysis, plasma TG levels were the only variable independently associated with LDL peak particle size., Conclusions: In this population, which appears to be somewhat protected by premature coronary artery disease, a low prevalence of the LDL pattern B was found in both men and women, and plasma TG could have a key role in regulating the LDL peak particle size. The follow up, still ongoing, will provide useful information on the predictive role of LDL peak particle size on cardiovascular risk, at least in a low-risk population.

Background and Methods: Lipoprotein(a) [Lp(a)] levels represent an independent risk factor for cardio- and cerebrovascular diseases. Since lipoprotein(a) levels show a wide variability even in subjects with similar apolipoprotein(a) isoforms, we investigated the contribution of apolipoprotein(a) heterozygosity to lipoprotein(a) variance. Lipoprotein(a) levels, apolipoprotein(a) isoforms identification and expression, and the correlation with other lipo-apolipoprotein parameters have been investigated in 628 subjects >18 years of age., Results: In our study, 246 subjects were found heterozygous for apolipoprotein(a) isoforms. Lipoprotein(a) levels were higher in females. About 40% of the subjects expressed the larger isoform more intensely than the dominant isoform. Lipoprotein(a) was correlated with apolipoprotein(a) dominant isoform size, HDL-cholesterol and smaller apolipoprotein(a) isoform expression rate. Lipoprotein(a) was independently correlated with the smaller apolipoprotein(a) isoform, with its expression rate and with LDL-cholesterol. The inclusion of the smaller apolipoprotein(a) expression rate in a multiple regression model explained at least an additional 4% of the lipoprotein(a) variance after correction for apolipoprotein(a) size., Conclusions: The smaller isoforms are not always effectively dominant in heterozygosis since 40% of the subjects expressed more the larger isoform. The individual variability of apolipoprotein(a) isoform expression in heterozygosis could explain part of the lipoprotein(a) levels variability., (Copyright 2002 Elsevier Science B.V.)

Epidemiological and pathogenetic evidences suggest a strong association between vascular risk factors and sporadic Alzheimer's disease (sAD). In agreement with the vascular hypothesis of AD, the role of various candidate genes for atherosclerosis has been investigated, leading to conflicting results. In order to clarify the significance of angiotensin-converting enzyme (ACE) gene insertion (I)/deletion (D) polymorphism in a group of patients with sAD, we conducted a case-control study including 149 cases and 149 age and sex matched controls. All subjects were genotyped for ACE and Apolipoprotein E (APOE). There were no significant differences in ACE genotype or allele frequencies between cases and controls, even after stratification for APOE4 carrier status. Our data suggest that the ACE I/D polymorphism is not associated to genetic susceptibility in sAD patients.

Objective: Knowledge of alimentary habits among populations permits a better definition of appropriate public health interventions. We designed the epidemiological project "Ventimiglia di Sicilia" to characterize the risk profile in a rural village with low total cholesterol levels and low early cardiovascular mortality but with a large prevalence of overweight and obesity, which previously have been significantly associated with total mortality., Methods: 488 individuals of age 20 to 69 years were included in the dietary survey conducted by a seven-day food record., Results: Alimentary habits were characterized by high consumption of total and complex carbohydrates (respectively 52.5 +/- 7.6% and 46.6 +/- 8.2% of daily energy) and by a low cholesterol intake (92.5 +/- 35.0 mg/1000 kcal/day). Fat intake was 34.7 +/- 7.7% of daily energy due to a higher consumption of monounsaturated fats in respect to saturated fats (respectively 20.5 +/- 5.1% and 10.2 +/- 2.9% of daily energy). In particular, in this population there was a large consumption of bread, pasta, fresh vegetables, olive oil and fruits. We also observed an excess of total calories (about 2900 kcal/day in men and 2100 kcal/day in women) not balanced by a high degree of physical activity levels. Furthermore we found a significant higher total and saturated fat consumption in the youngest individuals and in people with higher educational levels., Conclusions: Dietary habits of Ventimiglia di Sicilia still follow the nutritional characteristics typical of the Mediterranean diet. The high total calorie intake indicates a quantitative more than qualitative problem, which may account the large prevalence of overweight and obesity and may represent a public health issue that needs to be corrected in such a rural population.

Background and Aim: The populations of the Mediterranean area have a low incidence of cardiovascular disease (CHD). The aims of this paper are: 1) to present demographic data of the population of Ustica, a small island in the southern part of the Tyrrhenian sea that has reduced communications with the mainland and a diet presumably rich in fish; and 2) to evaluate the distribution of risk factors, plasma lipids, lipoproteins and dyslipidemias in this population., Methods and Results: We invited all of the free-living resident population aged more than 14 years (about 800 individuals) to participate in the study; 576 responded, for a participation rate of about 73%. The distribution of cardiovascular risk factors, plasma lipids, lipoproteins and dyslipidemias were evaluated in all of the subjects. More than 60% of the population was out of the normal weight range. Total and low-density lipoprotein cholesterol levels were respectively 207.4 +/- 46.7 and 141.7 +/- 42.4 mg/dL, and similar in males and females. Lipoprotein (a) (Lp[a]) levels presented the classical "skewed" distribution and, among the apolipoprotein(a) isoforms, there was a clear predominance of intermediate-sized kringle IV repeats. Overall, 43% of the subjects had a lipid disorder: the prevalence of hypercholesterolemia was 22.8% (3.2% with severe hypercholesterolemia terolemia > or = 300 mg/dL); low high-density lipoprotein cholesterol levels were found in 22.5%; the so-called lipid triad in 2.1%; and high Lp(a) levels in 6.2%. Large familial clusters were found for some lipid disorders., Conclusions: A large prevalence of body weight disturbances and high frequency of dyslipidemias are the main characteristics of this population. Ongoing data and future longitudinal studies will better clarify the relative influence of each parameter on CHD risk and total mortality.

The aim of the Epidemiological project "Ventimiglia di Sicilia" is to identify the cardiovascular risk factors in a Sicilian population with a low risk profile and healthy nutritional habits. The risk of cardiovascular mortality in older subjects (over 60 years of age) is presented for an 11 year follow-up. Females showed higher prevalence of diabetes mellitus, hypertension, obesity and higher levels of total, LDL and HDL cholesterol, factor VII activity and fibrinogen compared to males. Cardiovascular mortality was related to hypertension and obesity in males, to high factor VII activity, obesity and diabetes mellitus in females. In a Logistic Regression model the same variables were independently correlated to cardiovascular mortality with the exception of obesity. In conclusion, these findings suggest that in a population with a low risk profile, other factors, such as factor VII activity, may emerge as predictors of cardiovascular mortality.

Background and Aim: More than 750 mutations in the low-density lipoprotein (LDL) receptor gene are currently known to cause familial hypercholesterolemia (FH), but the array of mutations varies considerably in different populations. The definition of essentially all the LDL receptor gene mutations in a population is therefore a prerequisite for the implementation of nation-wide genetic testing for FH., Methods and Results: In this study, a screening strategy based on PCR-enzymatic digestion and PCR-allele specific hybridisation procedures was used to evaluate the frequency distributions of 11 known mutations in a cohort of 214 unrelated subjects meeting the diagnostic criteria of "probable" FH. We identified 20 mutation carriers (9.3%). One mutation (FH Palermo-1) occurred with a relatively high frequency, accounting for 7% of the entire study cohort. We also report the first observation of the receptor-negative mutation V408M (Afrikaner-2) in Italy., Conclusions: Our screening approach is not effective and, at least in our area, it is not a suitable alternative to the more expensive and time-consuming sequencing approach. However, our data suggest that it is possible to identify the molecular defect in about 10% of Sicilian patients with a clinical diagnosis of "probable FH" using a rapid laboratory diagnostic mutation panel. Four mutations were responsible for all of the diagnosed cases, and it could be reasonable to use this 4-mutation panel as a preliminary step before adopting a more complex laboratory approach.

Familial defective apolipoprotein (apo) B-100 together with familial hypercholesterolemia are the two common genetic conditions that cause hypercholesterolemia. Familial defective apolipoprotein B-100 is due to mutations around codon 3500 of the apo B gene. The most-characterized mutation is a G>A transition at nucleotide 10,708 that results in the substitution of arginine by glutamine at codon 3500 (Apo B Arg3500Gln). Two other mutations are caused by a C>T transition, one at nucleotide 10,800 (Apo B Arg3531Cys) and the other at nucleotide 10,707 (apo B Arg3500Trp). In the present study we describe three new Italian cases of familial defective apolipoprotein B-100 (Apo B Arg3500Gln), one from the Liguria region and two from Sicily, and the haplotype of the apo B gene co-segregating with the mutation. By screening two groups of probands, clinically diagnosed as having Familial Hypercholesterolemia (700 from mainland Italy and 305 from Sicily), the prevalence of familial defective apolipoprotein B-100 due to Arg3500Gln was found to be very low (0.28% and 0.65%, respectively). The Arg3531Cys mutation was not detected in any proband. In the three new families with Arg3500Gln mutation in the present study and in one previously described in Italy, the mutation was associated with a unique apo B haplotype, which is consistent with data previously reported for Caucasian patients [XbaI-, MspI+, EcoRI-, presence of the 5' signal peptide insertion (Ins) allele, and the 49-repeat allele of the 3'-VNTR].

Stroke incidence rates in the Mediterranean area are higher compared to northern European countries. In this study, we present the 8-year prospective data from a small rural Sicilian town. This population, consisting of 1351 subjects (622 males and 729 females), is homogeneous for ethnic background with traditional healthy dietary habits and shows low cholesterol mean levels. We found that the risk of stroke was significantly associated with the record of at least one previous neurological symptom (PNS), such as lack of strength, loss of vision or speech or possible drop attacks, and high hematocrit in males, and to high body mass index (BMI) and waist-hip ratio (WHR), diabetes, hypertension, high leukocyte count in females. We also documented age-related differences: stroke was associated in younger subjects (age<65 years) with diabetes, high BMI, high uric acid levels and in older patients (age>/=65 years) with high WHR, hypertension, diabetes, PNS, leukocyte count and hematocrit above the 95th percentile. Multivariate analysis demonstrated an independent association between stroke and age, diabetes, leukocyte count, hypertension and PNS. In conclusion, in this rural Sicilian population, the incidence rate of stroke is 1.72 cases per 1000/year in the subjects between 40 and 75 years of age. The risk factors associated with stroke are different in younger and older subjects. Leukocyte count, as an expression of an undergoing inflammatory process, may have a relevant role at least in the elderly.

Background and Aim: Extracranial cerebrovascular atherosclerosis is a common feature of hypercholesterolemia and carotid lesions are good predictors of cardiovascular events in the general population. Factors associated with the carotid damage of hypercholesterolemic patients and their relationships with the occurrence of clinical events are investigated in this study., Methods and Results: One hundred and seventeen cardiovascular event-free hypercholesterolemic subjects underwent a complete clinical examination to look for additional risk factors. A blood sample was collected for lipoprotein determination and an ultrasound high resolution B-mode imaging examination of the common carotid arteries was performed. Patients were treated according to the current guidelines during a 4-yr follow-up and all major cardiovascular events were recorded. The prevalence of subjects with increased intima-media thickness and plaque was 21.4% and 29.9% respectively, higher than in normolipidemic controls. Carotid lesions were significantly related to age, hypertension and LDL-cholesterol and HDL-cholesterol levels. The relative risk of developing a major clinical event was 3.92 (95% CI 1.54-9.95, p < 0.004) among categories of carotid status. At multivariate analysis, cardiovascular events were independently related to the diagnosis of familial hypercolesterolemia (FH), baseline carotid score and mean levels of LDL-cholesterol and HDL-cholesterol during the follow-up., Conclusions: Common risk factors cooperate with plasma lipoprotein levels in increasing the frequency of carotid lesions of hypercholesterolemic patients. Since such lesions are useful predictors of clinical events, B-mode ultrasound evaluation of the carotids should be routinely included in the management of these patients.

Objective: We investigated the prevalence of overweight and obesity and their relationships with the main cardiovascular risk factors in the population of Ventimiglia di Sicilia, a rural village in Southern Italy characterized by low cholesterol levels and by a low incidence of early coronary heart disease mortality. We related all deaths to body weight and fat distribution during an 8 y follow-up., Design: Cross-sectional and prospective observational study., Subjects: A total of 835 free-living individuals, 363 males and 472 females, of age between 20 and 69 y., Measurements: In all participants body weight, waist-to-hip ratio (WHR), cardiovascular risk factors and plasma lipids were measured. During the follow-up, total and cardiovascular deaths were registered., Results: We found a high overall prevalence of subjects with overweight or obesity (respectively 45.0% and 27.7%), with great differences among classes of age. As expected, body weight and fat distribution were associated with diabetes, hypertension, dyslipidemia and with a worsening of lipid profile. During the follow-up we registered 37 total and 11 cardiovascular deaths. All-cause and cardiovascular mortality risks were, respectively, 1.64 (95% CI 0.65-4.15) and 2.71 (95% CI 0.29-25.26) in subjects with a body mass index (BMI) of 27-29.99 kg/m2 and 2.45 (95% CI 1.03-5.87) and 5.36 (95% CI 1.41-62.01) in subjects with a BMI of > or =30 kg/m2 in comparison with participants with a BMI of <27 kg/m2, and 3.48 (95% CI 1.46-8.30) and 4.55 (95% CI 1.12-18.40) in subjects with a WHR higher than the median in comparison with individuals with a WHR lower than the median., Conclusion: The Ventimiglia di Sicilia Study highlights the great importance of overweight and obesity as a public health issue in a rural population and indicates that it is necessary to consider the impact of body weight and fat distribution on both total and CHD mortality.

Polymorphisms of apoE gene are able to modulate lipoprotein metabolism at different steps and to influence LDL-cholesterol (LDL-C) levels and also other lipoproteins features. Population studies documented large differences in the frequency of apoE alleles which could be even related to the prevalence of cardiovascular disease. In this study we evaluated the apoE genotypes and allele frequency in 576 subjects living in a small island in the Tyrrhenian Sea and the relative contribution of apoE polymorphism on plasma lipid and lipoprotein profile, including LDL particle size. We found a cumulative frequency of 0.073, 0.866 and 0.061 for epsilon2, epsilon3 and epsilon4 alleles respectively. Moreover epsilon3 subjects had only triglyceride levels significantly lower and LDL-C and lipoprotein (a) (Lp(a)) levels higher than epsilon2 carriers. LDL-particle size was significant smaller in epsilon2 subjects than both epsilon3 and epsilon4 carriers, but the difference disappeared when data were adjusted for triglycerides. In conclusion we have provided further evidence of a low prevalence of epsilon4 allele in a Mediterranean population which may represent a genetic protective factor of these populations. Environmental factors, such as diet, occurring in this area may have attenuated the influence of this gene on plasma lipoproteins.

Background: Lipoprotein(a) [Lp(a)] is a lipoprotein consisting of a low-density lipoprotein (LDL) particle linked to a polymorphic glycoprotein, apoprotein(a) [apo(a)]. Prior studies have reported high Lp(a) levels in the nephrotic syndrome, but it is still controversial whether this is due to the degree of hypoalbuminemia or proteinuria., Methods: To investigate a model of nephrotic syndrome in the absence of renal failure, we studied a group of 84 children in different clinical stages of the disease for a period of five years. We evaluated the direct relationships between lipoproteins, including Lp(a), and/or plasma albumin and proteinuria., Results: Lp(a) levels were significantly higher in the subjects with the active disease compared with patients in remission, and were also significantly different when subjects were ranked by albumin quartiles. Multiple regression analysis revealed that Lp(a) levels were inversely correlated with apo(a) isoform size and plasma albumin levels but not with the proteinuria/creatinine clearance ratio. Among subjects in complete remission, Lp(a) levels were different in patients with albumin levels below or above the fifth percentile. After the improvement of the clinical stage of the disease, the Delta% variation of albumin levels was related to the Delta% of apoB and LDL cholesterol (LDL-C), but not with the Delta% variation of Lp(a), whereas the Delta% variation of LDL-C was, in turn, related to the Delta% of Lp(a) levels., Conclusions: These results suggest that in the childhood nephrotic syndrome, the increased Lp(a) levels are mainly related to hypoalbuminemia, probably through a mechanism involving apoB overproduction, which leads to an increased number of LDL particles to be converted into Lp(a).

Background: Renal transplant recipients have an increased incidence of cardiovascular disease. These patients present abnormalities of lipoprotein profile which are persistent and involve an increasing number of individuals, suggesting the opportunity of an early therapeutic intervention., Methods: We evaluated the effects of a 10- to 12-week diet based on the American Heart Association step-one diet criteria, modified with an increased intake of monounsaturated fats and alimentary fibers, on lipid profile and lipid-related cardiovascular risk in 78 normolipidemic and hyperlipidemic renal transplant recipients., Results: Diet led to a significant reduction in total cholesterol levels by 10%, triglycerides by 6.5%, low-density lipoprotein (LDL)-cholesterol by 10.4% and LDL-cholesterol/high-density lipoprotein (HDL)-cholesterol ratio by 10%, whereas HDL-cholesterol levels remained unchanged. Dividing renal transplant recipients into risk classes according to the National Cholesterol Expert Program guidelines and LDL-cholesterol levels, we observed a progressively increasing reduction in total cholesterol and LDL-cholesterol levels among 'desirable LDL-cholesterol', 'borderline high-risk LDL-cholesterol' and 'high-risk LDL-cholesterol' patients, while HDL-cholesterol levels did not change in any group and the LDL-cholesterol/HDL-cholesterol ratio significantly decreased in 'borderline high-risk LDL-cholesterol' and in 'high-risk LDL-cholesterol' patients (respectively by 6.8%, p < 0.05, and by 21.1%, p < 0.0001). Reduction in triglyceride levels was statistically significant only in subjects with 'desirable LDL-cholesterol' (by 12.3%, p < 0.01). Patients in the 'desirable LDL-cholesterol' class increased from 28 (35.9% of total patients) before diet to 45 (57.7% of total patients, p < 0.01), while subjects in the 'high-risk LDL-cholesterol' class reduced from 24 (30.8% of total patients) to 8 (10.2% of total patients, p < 0.005)., Conclusion: These data suggest the possibility of a nutritional hypolipidemic approach in renal transplant recipients, even if normolipidemic. Dietetic treatment determined an inversion in the typical trend of renal transplant recipients, reducing instead of increasing the number of subjects with hypercholesterolemia, permitting the selection of individual candidates for further pharmacological treatment by carefully evaluating risk/benefit costs.

The aim of this study was to evaluate the influence of lipoprotein(a) levels and apoprotein(a) isoform size in determining the low cardiovascular risk of a rural, inland Sicilian population. Plasma levels of total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, lipoprotein(a) and apoprotein B and AI were measured in a sample of 278 subjects (141 males, 137 females) representative of a population of 1351 subjects (622 males, 729 females). The apoprotein(a) isoforms were also identified. Results indicated that the levels of the common lipo-apoliproprotein parameters were lower than those of other populations, while lipoprotein(a) plasmatic levels and apoprotein(a) isoform distribution were similar to those of other Caucasian populations. The distribution of lipoprotein(a) levels was skewed to the right, with a higher prevalence of low levels, the apoprotein(a) isoforms most strongly represented in our sample were of intermediate size (25-27 kringles IV). Univariate analysis showed that lipoprotein(a) levels were correlated to apoprotein(a) isoform size (R = -0.48, p < 0.001) and to the age of the subjects (R = +0.13, p < 0.01). In a multiple regression analysis, lipoprotein(a) levels were correlated to the apoprotein(a) isoform size of the homozygous isoforms or smaller heterozygous isoforms, while larger heterozygous forms were not correlated. In conclusion, our study showed that in our population, lipoprotein(a) levels and apoprotein(a) isoforms are similar to those of other Caucasian populations. Other factors, such as the physical activity of a rural population or the Mediterranean diet, must be considered in order to explain the lower cardiovascular risk of this population.

In order to assess the role of HDL on longevity, we studied HDL subfraction distribution in centenarian women compared with a group of weight- and gender-matched healthy normolipidemic controls. We did not find any significant difference in the mean plasma lipid, apolipoprotein, and Lp(a) levels. On the contrary, in spite of similar HDL-cholesterol concentrations (1.32 +/- 0.41 mmol/l in centenarians vs. 1.32 +/- 0.25 mmol/l in controls, p = not significant), HDL2b and HDL3a levels were, respectively, significantly increased and significantly reduced in centenarians in comparison with controls (HDL2b 32.4 +/- 9.2% in centenarians vs. 23.4 +/- 7.7% in controls, p < 0.002, and HDL3a 26.3 +/- 9.8% in centenarians vs. 34.1 +/- 7.3% in controls, p < 0.01). Moreover, HDL2b levels were significantly raised and HDL3a levels were significantly reduced in centenarians in comparison with both 'middle-aged' and 'elderly' subjects, whereas no difference for any HDL subfraction was found between the two groups of controls of different ages. Age was significantly correlated with HDL2b and HDL3a (respectively, +0.452, p < 0.001, and -0.370, p < 0.01) in all subjects, but not with all the other lipid, lipoprotein and apolipoprotein parameters, but we observed a large overlapping of individual values of HDL2b between centenarians and controls. Since HDL2b levels were found to be inversely correlated with coronary heart disease risk, we could speculate that, in some cases, this may probably favor a healthy ageing, but long-term longitudinal studies are necessary to define the relative importance of HDL subfractions distribution as a marker of longevity. Probably other factors or clinical characteristics play a major role in the ageing process.

Truncations of apolipoprotein (apo) B shorter than 3200 amino acids (3200/4536 = apoB-70) do not possess the LDL receptor-recognition domain and are not recognized by altered cells with normally functioning LDL receptors. To ascertain which organs remove such truncated apoB-containing particles, we isolated apoB-31-, apoB-38.9-, and apoB-43.7-containing particles from plasmas of familial hypobetalipoproteinemia heterozygous humans by a combination of sequential ultracentrifugation and preparative electrophoresis. Particles with labeled 125I- or 131I-dilactitol tyramine (I-DLT), were injected into New Zealand White rabbits, along with I-DLT-apoB-100-containing LDLs, and the decay of 125I- and 131I-TCA-precipitated counts was followed over 24 hours. At the end of 24 hours, rabbits were anesthetized and their bodies perfused. Organs were removed and homogenized, and TCA-precipitable counts determined. Fractional catabolic rates of apoB truncation particles were two to five times greater than those of apoB-100 LDLs. ApoB truncations accumulated in adrenals at one fifth the rates of apoB-100 LDL, compatible with the functional absences of LDL receptor-recognition domains in truncated apoBs. The major organ of uptake for apoB-100-LDLs was the liver, whereas truncation particles were readily removed by the kidney (kidney: liver uptake ratios were 0.10 to 0.30 for apoB-100 LDLs and 1.03 to 3.77 for truncations). Spleens accumulated little of either apoB-100 or truncation particles, suggesting particles were not "damaged" or aggregated. Thus, the absence of > 56% of the carboxyl end of apoB-100 increases the plasma clearance and redirects the organ uptake of the apoB truncation-containing lipoproteins from liver to kidney.

We describe a new truncation of apolipoprotein (apo) B in a white kindred with familial hypobetalipoproteinemia (FHBL). Apo B-43.7, found in a daughter and her father, was due to a C --> T change in base position 6162 of the apo B gene converting the arginine (residue 1986) codon CGA to a stop codon TGA. Both subjects were heterozygotes, and both apo B-43.7- and apo B-100-containing particles were present in plasma. On density gradient ultracentrifugation (DGUC), approximately 30% to 40% of apo B-43.7 floated with very-low-density lipoprotein (VLDL)/intermediate-density lipoprotein (IDL)-density particles and 60% to 70% floated with high-density lipoprotein (HDL)-density particles. To assess the metabolism of apo B, 13C-leucine was infused and its rates of appearance in and disappearance from apo B-43.7- and apo B-100-containing particles were quantified by multicompartmental kinetic analysis. Apo B-100 entered plasma via VLDL with a production rate of 30 mg x kg-1 x d-1. Fractional catabolic rates (FCRs) for apo B-100 VLDL, IDL, and low-density lipoprotein (LDL) were 20.0, 16.0, and 0.46 pools x d-1, respectively. The production rate of apo B-43.7 was 9.6 mg x kg-1 x d-1, and FCRs for apo B-43.7 VLDL- and HDL-like particles were 12.0 and 1.8 pools x d-1, respectively. Approximately 30% of apo B-43.7 in HDL-density particles was derived from VLDL apo B-43.7, and about 70% appeared to enter the plasma as HDLs. The relatively low production rate of apo B-43.7 is compatible with previous reports that apo B truncations are produced at lower rates than their apo B-100 counterparts.

Since the high rate of cardiovascular disease in renal transplant recipients, alterations of lipoprotein profile in such patients were extensively evaluated, but the HDL subclass profile was not completely clarified. Renal transplant recipients usually show normal to high plasma levels of HDL cholesterol, even if some investigations suggested a persistence of low HDL2 levels: this was not useful in terms of cardiovascular protection. We designed this study in order to evaluate HDL subfractions distribution in renal transplant recipients. We studied 55 renal transplant recipients, treated with prednisone, azathioprine and/or cyclosporine, and 34 healthy normolipidemics as controls. In all subjects cholesterol, triglycerides, LDL cholesterol, HDL cholesterol, apolipoproteins A-I and B levels and HDL subfractions, as determined by nondenaturing polyacrylamide gradient gel electrophoresis, were assayed. Renal transplant recipients had cholesterol, triglycerides, LDL cholesterol and apolipoproteins A-I and B levels significantly higher than controls; HDL cholesterol levels were slightly, but not significantly, increased in comparison with controls (respectively 51.1 +/- 15.5 and 46.1 +/- 10.8 mg/dl). Multivariate analysis showed that only the time since transplantation was significantly associated with HDL cholesterol levels. When HDL subfractions were analyzed, renal transplant recipients presented significantly lower levels of HDL3a and HDL3b and, in males, higher levels of HDL2b than controls. HDL cholesterol levels were positively correlated with HDL2b levels in both renal transplant recipients and controls, and negatively correlated with HDL3b in controls. In conclusion, in renal transplant recipients, we failed to demonstrate any decrease of HDL2 particles. On the basis of a nonatherogenic HDL profile, we suggest that the increased cardiovascular risk in renal transplant recipients might be accounted for by other risk factors.

To assess whether very low concentrations of LDL affected lipoprotein(a) [Lp(a)] concentrations and apo(a) associations with lipoproteins, we studied Lp(a) levels and associations in heterozygous subjects with familial hypobeta-lipoproteinemia FHBL) associated with several truncated forms of apoB-100, ranging from apoB-31 to apoB-89. Distributions of apo(a) isotypes were assessed by a combined electrophoresis-immunoblotting procedure that detects 34 isoforms. Lp(a) concentrations were quantified by two ELISAs, one detecting total apo(a) and the other apoB-bound apo(a) in plasma. Associations of apo(a) with plasma lipoproteins were evaluated by gel permeation chromatography (FPLC) and DGUC followed by analyses of elution and gradient fractions by apo(a) ELISA. In addition, associations were examined by nondenaturing electrophoresis or immunoprecipitation of whole plasma and examination of contents by immunoblotting. Finally, interactions between r-apo(a) and LDLs were evaluated in reconstitution experiments. The distributions of apo(a) isotypes did not differ between FHBL-affected and unaffected members of the same kindreds, and concentrations of Lp(a) were similar even when subjects were matched for isotypes both within and across kindreds. In subjects heterozygous for apo(a) isoforms, the smaller isoforms were inversely related to Lp(a) concentrations, the larger isoforms were not. The regression lines between Lp(a) concentrations and the smaller apo(a) isoforms were significant and negative in slope for both FHBL-affected and unaffected subjects, but the slopes of the lines did not differ. In multiple regression analyses, only the sizes of the smaller apo(a) isoforms contributed to the prediction of Lp(a) concentrations. ApoB-size made no difference. In simple apoB-100/apoB-truncation heterozygotes, virtually all apo(a) was complexed with apoB-100-containing particles but not apoB-truncation particles, and r-apo(a) recombined with apoB-100-containing LDLs but not with apoB-89-containing LDLs. Thus, (1) low apoB levels do not affect the plasma concentrations of Lp(a), (2) apo(a) binds apoB-100 to form Lp(a) particles of usual sizes and densities, and (3) apoB truncations even as large as apoB-89 do not form covalent bands with apo(a), although noncovalent associations with apoB-89 may be present in plasma.

Relationships between plasma lipoproteins and cerebrovascular atherosclerosis are not completely clear. In a group of asymptomatic nondiabetic normolipidemic subjects, plasma lipid and apolipoprotein profiles have been related to extracranial carotid atherosclerotic lesions, as assessed by B-mode ultrasonography and independent relations between lipid and clinical parameters and carotid atherosclerosis have been evaluated. We have found that subjects with atherosclerotic lesions (both intimal thickening or plaque) had TG levels and CHO/HDL-C and LDL-C/HDL-C ratios significantly higher and HDL-C and apo A-I levels significantly lower in comparison with subjects with normal arteries. When patients were divided according to the lesions of carotid arteries subjects with atherosclerotic plaque presented HDL-C and apo A-I levels significantly reduced and TG and apo B levels and CHO/HDL-C and LDL-C/HDL-C ratios significantly increased in comparison with subjects with normal arteries, and HDL-C levels reduced and CHO/HDL-C and LDL-C/HDL-C ratios increased in comparison with subjects with intimal thickening. Patients with intimal thickening and normal subjects differed for HDL-C and TG levels and CHO/HDL-C and LDL-C/HDL-C ratios. At multivariate analysis HDL-C levels (negatively), age, hypertension and cigarette smoking (positively) resulted independently associated with cerebrovascular atherosclerosis. Our data seem to show that, although several lipid and apoprotein abnormalities are able to initiate the atherosclerotic process in extracranial carotid district, probably the presence of low HDL-cholesterol levels is an important condition to determine the further worsening of the lesions.

Cigarette smoking produces lipo-apoprotein modifications, which makes it more atherogenic. In this study we have evaluated lipids and apoproteins in 178 normolipidemic, healthy subjects, in relation to their smoking habits. In smokers we have found lower levels of HDL-cholesterol and apo A-I and higher levels of triglyceride and apo B. Number of cigarette smoked in a day directly correlated with triglycerides and apo B (r = 0.321 and 0.313 respectively) and inversely with HDL-cholesterol (r = -0.274). These alterations seem to be due to an inhibition that smoking could cause on lipolytic processes. Further studies need to establish influences that smoking-related alterations have in the atherosclerotic lesions of smokers.

Post-prandial profiles of plasma lipids and apoproteins have been studied in 13 hypertriglyceridaemic patients and in 24 normolipidaemic subjects who acted as controls. Triglyceride curves were different in the two groups: type IV patients reached the peak later than the controls (7-h vs 4 1/2-h) and cleared plasma triglycerides more slowly. The magnitude of post-prandial response was found to be higher in hypertriglyceridaemic patients. Positive correlations were also found between triglycerides response and fasting levels of triglycerides, apo B, apo C-II, apo C-III and apo E levels and negative correlations (not significant) with HDL-C levels in both hypertriglyceridemics and controls. In normolipidaemic subjects the triglyceride increase area was also correlated with age, BMI and total cholesterol, while in type IV patients with apo A-I and apo A-II levels. These data confirm that the magnitude of post-prandial phase is influenced by fasting levels of triglycerides-rich lipoproteins and that HDL are important determinants in the control of the post-prandial response. The most relevant finding in this study was the difference of the post-prandial profile of apoproteins C-II, C-III and E. These apoproteins significantly decreased nine hours after meal in the controls, while in hypertriglyceridaemics these apoproteins showed a rise over time. On the contrary apo A-I, apo A-II and apo B curves presented a similar profile in both groups. Possible mechanisms have been discussed, but further studies are necessary to understand the metabolic defects responsible for this behaviour in hypertriglyceridaemia.

Two non familial cases of pseudoachondroplasia are reported. The patients, observed at 4 years and 6 months and 5 years respectively, show short-limb dwarfism with disproportionated long trunk and with normal head and face. Flattening of vertebral bodies with biconvex deformity and short tubular bones with irregular epiphyses and metaphyses are the major radiographic features. In these patients to state the type of genetic transmission is very arduous, as the genetic heterogeneity of the pseudoachondroplasia.