Adiponectin concentration data improve the estimation of atherosclerotic risk in normal and in overweight subjects.

BACKGROUND: The combinations of adipokines and body mass parameters to estimate carotid atherosclerotic disease have not been completely delineated. OBJECTIVE: To test the combinations of well-established, easily accessible body mass indices and circulating biomarkers to identify increased carotid intima-media thickness (cIMT) in a primary prevention setting. DESIGN AND PATIENTS: In a cross-sectional analysis of 339 asymptomatic individuals with no history of cardiovascular events, inflammatory and insulin sensitivity biomarkers as well as adipokine levels were measured and combined with body mass parameters to evaluate the best marker for increased cIMT. RESULTS: As isolated parameters, body mass index (BMI) and adiponectin best identified abnormal cIMT (P = .04). Adiponectin levels were also linked to the relationship between BMI and cIMT (ß = 0.0371; P = .01). Twenty-nine individuals with increased cIMT were missed by BMI alone but detected by combining BMI and adiponectin measurements. When compared with BMI alone, the combination of adiponectin plus BMI improved the c-statistic (0.549-0.567) and the integrated discrimination improvement index (0.01725; P = .021). Segregation of individuals by the combined use of BMI + adiponectin is associated with significant differences in insulin sensitivity, glomerular filtration rate, systemic inflammatory activity, dyslipidaemia and cIMT. CONCLUSIONS: Combining plasma adiponectin measurements and BMI improves estimation of cIMT as compared to anthropometric parameters.

Apolipoprotein E mRNA expression in mononuclear cells from normolipidemic and hypercholesterolemic individuals treated with atorvastatin.

BACKGROUND: Apolipoprotein E (apoE) is a key component of the lipid metabolism. Polymorphisms at the apoE gene (APOE) have been associated with cardiovascular disease, lipid levels and lipid-lowering response to statins. We evaluated the effects on APOE expression of hypercholesterolemia, APOE ε2/ε3/ε4 genotypes and atorvastatin treatment in Brazilian individuals. The relationship of APOE genotypes and plasma lipids and atorvastatin response was also tested in this population. METHODS: APOE ε2/ε3/ε4 and plasma lipids were evaluated in 181 normolipidemic (NL) and 181 hypercholesterolemic (HC) subjects. HC individuals with indication for lowering-cholesterol treatment (n = 141) were treated with atorvastatin (10 mg/day/4-weeks). APOE genotypes and APOE mRNA in peripheral blood mononuclear cells (PBMC) were analyzed by TaqMan real time PCR. RESULTS: HC had lower APOE expression than NL group (p < 0.05) and individuals with low APOE expression showed higher plasma total and LDL cholesterol and apoB, as well as higher apoAI (p < 0.05). Individuals carrying ε2 allele have reduced risk for hypercholesterolemia (OR: 0.27, 95% I.C.: 0.08-0.85, p < 0.05) and NL ε2 carriers had lower total and LDL cholesterol and apoB levels, and higher HDL cholesterol than non-carriers (p < 0.05). APOE genotypes did not affect APOE expression and atorvastatin response. Atorvastatin treatment do not modify APOE expression, however those individuals without LDL cholesterol goal achievement after atorvastatin treatment according to the IV Brazilian Guidelines for Dyslipidemia and Atherosclerosis Prevention had lower APOE expression than patients with desirable response after the treatment (p < 0.05). CONCLUSIONS: APOE expression in PBMC is modulated by hypercholesterolemia and the APOE mRNA level regulates the plasma lipid profile. Moreover the expression profile is not modulated neither by atorvastatin nor APOE genotypes. In our population, APOE ε2 allele confers protection against hypercholesterolemia and a less atherogenic lipid profile. Moreover, low APOE expression after treatment of patients with poor response suggests a possible role of APOE level in atorvastatin response.

Pharmacogenetics of OATP transporters reveals that SLCO1B1 c.388A>G variant is determinant of increased atorvastatin response.

AIMS: The relationship between variants in SLCO1B1 and SLCO2B1 genes and lipid-lowering response to atorvastatin was investigated. MATERIAL AND METHODS: One-hundred-thirty-six unrelated individuals with hypercholesterolemia were selected and treated with atorvastatin (10 mg/day/4 weeks). They were genotyped with a panel of ancestry informative markers for individual African component of ancestry (ACA) estimation by SNaPshot(®) and SLCO1B1 (c.388A>G, c.463C>A and c.521T>C) and SLCO2B1 (-71T>C) gene polymorphisms were identified by TaqMan(®) Real-time PCR. RESULTS: Subjects carrying SLCO1B1 c.388GG genotype exhibited significantly high low-density lipoprotein (LDL) cholesterol reduction relative to c.388AA+c.388AG carriers (41 vs. 37%, p = 0.034). Haplotype analysis revealed that homozygous of SLCO1B1*15 (c.521C and c.388G) variant had similar response to statin relative to heterozygous and non-carriers. A multivariate logistic regression analysis confirmed that c.388GG genotype was associated with higher LDL cholesterol reduction in the study population (OR: 3.2, CI95%:1.3-8.0, p < 0.05). CONCLUSION: SLCO1B1 c.388A>G polymorphism causes significant increase in atorvastatin response and may be an important marker for predicting efficacy of lipid-lowering therapy.

Functional analysis of PCSK9 3'UTR variants and mRNA-miRNA interactions in patients with familial hypercholesterolemia.

Aim: Functional analysis of PCSK9 3'UTR variants and mRNA-miRNA interactions were explored in patients with familial hypercholesterolemia (FH). Materials & methods:PCSK9 3'UTR variants were identified by exon-targeted gene sequencing. Functional effects of 3'UTR variants and mRNA-miRNA interactions were analyzed using in silico and in vitro studies in HEK293FT and HepG2 cells. Results: Twelve PCSK9 3'UTR variants were detected in 88 FH patients. c.*75C >T and c.*345C >T disrupted interactions with miR-6875, miR-4721 and miR-564. Transient transfection of the c.*345C >T decreased luciferase activity in HEK293FT cells. miR-4721 and miR-564 mimics reduced PCSK9 expression in HepG2 cells. Conclusion:PCSK9 c.*345C >T has a possible role as loss-of-function variant. miR-4721 and miR-564 downregulate PCSK9 and may be useful to improve lipid profile in FH patients.

Pleiotropic effects with equivalent low-density lipoprotein cholesterol reduction: comparative study between simvastatin and simvastatin/ezetimibe coadministration.

BACKGROUND: Coadministration of any statin with ezetimibe is as effective as using high doses of the same statin in the reduction of low-density lipoprotein cholesterol (LDL-c). There may be other effects called pleiotropics. OBJECTIVE: To compare the effectiveness of 2 different treatments that obtain equivalent LDL-c reductions (80 mg of simvastatin, once a day and coadministration of 10 mg of simvastatin and 10 mg of ezetimibe, once a day) over endothelial function and inflammation. METHODS: Twenty-three randomized patients with hypercholesterolemia in a 2 x 2 crossover protocol were studied. Endothelial function was analyzed by ultrasound assessment of endothelial dependent flow-mediated vasodilation of the brachial artery, and inflammation was estimated by high-sensitivity C-reactive protein (hs-CRP). RESULTS: LDL-c reduction was similar between the 2 treatments with simvastatin/ezetimibe and with simvastatin (P < 0.001); no difference between treatments was found (P = 0.968). Both treatments improved significantly the endothelial function [3.61% with simvastatin/ezetimibe (P = 0.003) and 5.08% with simvastatin (P < 0.001)]; no difference was found between the 2 treatments (P = 0.291). hs-CRP had a 23% reduction with simvastatin/ezetimibe (P = 0.004) and a 30% reduction with simvastatin alone (P = 0.01), with no significant difference between the 2 treatments (P = 0.380). CONCLUSION: The 2 forms of treatment presented similar pleiotropic effects: improvement in endothelial function and decrease in hs-CRP levels.

CYP3A53A allele is associated with reduced lowering-lipid response to atorvastatin in individuals with hypercholesterolemia.

BACKGROUND: The cytochrome P450 isoenzyme 3A5 (CYP3A5) has an important role on biotransformation of xenobiotics. CYP3A5 SNPs have been associated with variations on enzyme activity that can modify the metabolism of several drugs. METHODS: In order to evaluate the influence of CYP3A5 variants on response to lowering-cholesterol drugs, 139 individuals with hypercholesterolemia were selected. After a wash-out period of 4 weeks, individuals were treated with atorvastatin (10 mg/day/4 weeks). Genomic DNA was extracted by a salting-out procedure. CYP3A5*3C, CYP3A5*6 and CYP3A5*1D were analyzed by PCR-RFLP and DNA sequencing. RESULTS: >Frequencies of the CYP3A5*3C and CYP3A5*1D alleles were lower in individuals of African descent (*3C: 47.8% and *1D: 55.2%) than in non-Africans (*3C: 84.9% and *1D 84.8%, p<0.01). Non-Africans carrying *3A allele (*3C and *1D combined alleles) had lower total and LDL-cholesterol response to atorvastatin than non-*3A allele carriers (p<0.05). CONCLUSION: CYP3A5*3A allele is associated with reduced cholesterol-lowering response to atorvastatin in non-African individuals.

Statin-associated muscle symptoms: position paper from the Luso-Latin American Consortium.

In the last two decades, statin therapy has proved to be the most potent isolated therapy for attenuation of cardiovascular risk. Its frequent use has been seen as one of the most important elements for the reduction of cardiovascular mortality in developed countries. However, the recurrent incidence of muscle symptoms in statin users raised the possibility of causal association, leading to a disease entity known as statin associated muscle symptoms (SAMS). Mechanistic studies and clinical trials, specifically designed for the study of SAMS have allowed a deeper understanding of the natural history and accurate incidence. This set of information becomes essential to avoid an unnecessary risk of severe forms of SAMS. At the same time, this concrete understanding of SAMS prevents overdiagnosis and an inadequate suspension of one of the most powerful prevention strategies of our times. In this context, the Luso-Latin American Consortium gathered all available information on the subject and presents them in detail in this document as the basis for the identification and management of SAMS.

Antioxidant effect of simvastatin is not enhanced by its association with alpha-tocopherol in hypercholesterolemic patients.

Among the pleiotropic effects of statins, their antioxidant action may be involved in their protective effects. Thus, we investigated the antioxidant effect of simvastatin, associated or not with alpha-tocopherol, on levels of electronegative low-density lipoprotein (LDL-), nitrotyrosine, thiols (homocysteine, glutathione, cysteine, methionine), and lipid-soluble antioxidants in blood plasma of hypercholesterolemic subjects. In this study, 25 hypercholesterolemic subjects were treated for 2 months with simvastatin (20 mg/day) and with simvastatin (20 mg/day) + alpha-tocopherol (400 IU/day). Concentrations of thiols were determined by high-performance capillary electrophoresis-laser-induced fluorescene. Lipid-soluble antioxidants were determined by HPLC, and LDL-, and nitrotyrosine by ELISA. Simvastatin, independent of its association with alpha-tocopherol, reduced plasma concentrations of LDL-, nitrotyrosine, total cholesterol, and LDL cholesterol and the LDL cholesterol/HDL cholesterol ratio. Neither simvastatin nor simvastatin plus alpha-tocopherol altered plasma levels of the thiols analyzed. alpha-Tocopherol did not change the antioxidant effect of simvastatin on the levels of LDL- and nitrotyrosine in hypercholesterolemic subjects. The reduction of LDL- and nitrotyrosine by simvastatin seems to be related to the pleiotropic effects of this statin, and it may have an important protective effect against endothelial dysfunction and atherosclerosis.

Effects of simvastatin and L-arginine on vasodilation, nitric oxide metabolites and endogenous NOS inhibitors in hypercholesterolemic subjects.

Hypercholesterolemia is linked to endothelial dysfunction and enhancement of the endogenous inhibitor of NO synthase. The statins have lipid-lowering and pleiotropic properties, which could exert protective effects on the endothelium in hypercholesterolemia. The association of L-arginine with simvastatin could promote a further improvement on endothelial function in this condition. Thus, we investigated whether simvastatin, with or without supplementation with L-arginine, could improve endothelium-dependent vasodilation. In this study, 25 hypercholesterolemic subjects were treated according to the following protocol: washout period of 1 month; simvastatin (20 mg/day) for 2 months; simvastatin (20 mg/day) + L-arginine (7 g/day) for 2 months. From these patients, 10 were chosen at random for evaluation of vascular function by high resolution ultrasonography of the brachial artery. In subjects treated with simvastatin plus L-arginine, an increase of L-arginine levels (68%) and L-arginine/asymmetric dimethylarginine (ADMA) ratio (67%) were observed. Simvastatin reduced the plasma concentrations of NO metabolites nitrite + nitrate (NOx: 34%), S-nitrosothiols (RSNO: 42%), total cholesterol (25%), low density lipoprotein (LDL)-cholesterol (36%) and the LDL-cholesterol/high density lipoprotein (HDL-cholesterol ratio (34%). Simvastatin, associated or not to L-arginine, did not affect ADMA levels and endothelium-dependent vasodilation. Our data showed that simvastatin reduced the plasma concentrations of NOx and RSNO without affecting either the levels of ADMA or endothelium-dependent vasodilation in hypercholesterolemia.

Influence of PCSK9 polymorphisms on plasma lipids and response to atorvastatin treatment in Brazilian subjects.

BACKGROUND: The proprotein convertase subtilisin/kexin type 9 (PCSK9) has a key role in the regulation of plasma low-density lipoprotein (LDL) cholesterol by enhancing the degradation of LDL receptor. Functional variants in PCSK9 have been associated with differences in plasma lipids and may contribute to the variability of the response to cholesterol-lowering drugs. OBJECTIVE: To investigate the influence of PCSK9 variants on plasma lipid profile and response to atorvastatin in Brazilian subjects. METHODS: PCSK9 E670G, I474V, and R46L single nucleotide polymorphisms (SNPs) and plasma lipids were evaluated in 163 hypercholesterolemics (HC) and 171 normolipidemics (NL). HC patients with indication for cholesterol-lowering drug therapy (n = 128) were treated with atorvastatin (10 mg/d/4 wk). PCSK9 SNPs were analyzed by real time polymerase chain reaction. RESULTS: Frequencies of the PCSK9 SNPs were similar between the HC and NL groups. Logistic regression analysis showed a trend of association between PCSK9 E670G and hypercholesterolemia after adjustment for covariates (P = .059). The 670G allele was associated with high basal levels of LDL cholesterol (P = .03) in HC patients using the extreme discordant phenotype method. No association tests were performed for R46L variant because of its very low frequency, whereas the I474V polymorphism and PCSK9 haplotypes were not related to hypercholesterolemia or variability on plasma lipids in both NL and HC groups (P > .05). LDL cholesterol reduction in response to atorvastatin was not influenced by PCSK9 genotypes or haplotypes. CONCLUSIONS: PCSK9 E670G polymorphism but not I474V contributes to the variability on plasma LDL cholesterol levels in hypercholesterolemic subjects. Both PCSK9 variants have no influence on cholesterol-lowering response to atorvastatin.

Atorvastatin and hormone therapy influence expression of ABCA1, APOA1 and SCARB1 in mononuclear cells from hypercholesterolemic postmenopausal women.

BACKGROUND: Reverse cholesterol transport (RCT) has been inversely related to atherosclerosis and cardiovascular risk. The influence of menopause in the RCT process is poorly understood and the effects of cholesterol-lowering interventions, including statins and hormone therapy (HT), on genes controlling the RCT in postmenopausal women are also unknown. METHODS: The effects on serum lipids and expression profile of genes involved in RCT - APOA1, ABCA1, ABCG1, SCARB1 and LXRA - were evaluated by TaqMan(®) quantitative PCR in peripheral blood mononuclear cells (PBMC) from 87 postmenopausal hypercholesterolemic women treated with atorvastatin (AT, n=17), estrogen or estrogen plus progestin (HT, n=34) and estrogen or estrogen plus progestin associated with atorvastatin (HT+AT, n=36). RESULTS: Atorvastatin and HT treatments reduced the mRNA levels of APOA1 and SCARB1, respectively, whereas ABCA1 expression was reduced after all treatments. Although the expression of LXRA, an important transcription factor controlling the expression of genes involved in RCT, was not modified after any treatment, it was correlated with ABCA1, APOA1 and SCARB1 RNAm values before and after treatments, however no correlation with ABCG1 was observed. In a linear regression analysis, HT was related to an increase in apoAI levels after treatment when compared to atorvastatin and, moreover, higher SCARB1 and ABCA1 basal expression were also associated with decreased apoAI levels after treatments. CONCLUSION: ABCA1 mRNA levels are decreased by atorvastatin and HT, however these treatments have a differential effect on APOA1 and SCARB1 expression in PBMC from postmenopausal women. Basal ABCA1 and SCARB1 expression profile could be helpful markers in predicting the effect of atorvastatin and HT on RCT, according to the changes in apoAI levels in this sample population.

Atorvastatin and hormone therapy effects on APOE mRNA expression in hypercholesterolemic postmenopausal women.

Menopause is associated with changes in lipid levels resulting in increased risk of atherosclerosis and cardiovascular events. Hormone therapy (HT) and atorvastatin have been used to improve lipid profile in postmenopausal women. Effects of HT, atorvastatin and APOE polymorphisms on serum lipids and APOE and LXRA expression were evaluated in 87 hypercholesterolemic postmenopausal women, randomly selected for treatment with atorvastatin (AT, n=17), estrogen or estrogen plus progestagen (HT, n=34) and estrogen or estrogen plus progestagen associated with atorvastatin (HT+AT, n=36). RNA was extracted from peripheral blood mononuclear cells (PBMC) and mRNA expression was measured by TaqMan(®) PCR. APOE ɛ2/ɛ3/ɛ4 genotyping was performed using PCR-RFLP. Total cholesterol (TC), LDL-c and apoB were reduced after each treatment (p<0.001). Triglycerides, VLDL-c and apoAI were reduced only after atorvastatin (p<0.05), whereas triglycerides and VLDL-c were increased after HT (p=0.01). HT women had lower reduction on TC, LDL-c and apoB than AT and HT+AT groups (p<0.05). APOE mRNA expression was reduced after atorvastatin treatment (p=0.03). Although LXRA gene expression was not modified by atorvastatin, it was correlated with APOE mRNA before and after treatments. Basal APOE mRNA expression was not influenced by gene polymorphisms, however the reduction on APOE expression was more pronounced in ɛ3ɛ3 than in ɛ3ɛ4 carriers. Atorvastatin down-regulates APOE mRNA expression and it is modified by APOE genotypes in PBMC from postmenopausal women.

Differentiation of African components of ancestry to stratify groups in a case-control study of a Brazilian urban population.

BACKGROUND: Balancing the subject composition of case and control groups to create homogenous ancestries between each group is essential for medical association studies. METHODS: We explored the applicability of single-tube 34-plex ancestry informative markers (AIM) single nucleotide polymorphisms (SNPs) to estimate the African Component of Ancestry (ACA) to design a future case-control association study of a Brazilian urban sample. RESULTS: One hundred eighty individuals (107 case group; 73 control group) self-described as white, brown-intermediate or black were selected. The proportions of the relative contribution of a variable number of ancestral population components were similar between case and control groups. Moreover, the case and control groups demonstrated similar distributions for ACA <0.25 and >0.50 categories. Notably a high number of outlier values (23 samples) were observed among individuals with ACA <0.25. These individuals presented a high probability of Native American and East Asian ancestral components; however, no individuals originally giving these self-described ancestries were observed in this study. CONCLUSIONS: The strategy proposed for the assessment of ancestry and adjustment of case and control groups for an association study is an important step for the proper construction of the study, particularly when subjects are taken from a complex urban population. This can be achieved using a straight forward multiplexed AIM-SNPs assay of highly discriminatory ancestry markers.

Influence of SCARB1 polymorphisms on serum lipids of hypercholesterolemic individuals treated with atorvastatin.

BACKGROUND: The SR-BI is a key component on the cholesterol metabolism. Polymorphisms in the SR-BI gene (SCARB1) were related with variations on plasma lipoprotein profile and other risk factors for cardiovascular disease. We tested the relationship of 3 SCARB1 single nucleotide polymorphisms (SNPs) with hypercholesterolemia in a Brazilian population and whether these variants can influence lipid-lowering response to atorvastatin. METHODS: c.4G>A, c.726+54C>T and c.1050C>T SNPs and serum concentrations of lipid and apolipoproteins were evaluated in 147 hypercholesterolemic (HC) and 185 normolipidemic (NL) unrelated Brazilian subjects. HC patients were treated with atorvastatin (10 mg/day/4 weeks). RESULTS: Frequencies of SCARB1 polymorphisms were similar between the HC and NL groups (p>0.05). The T allele for c.726+54C>T was associated with higher LDL-c in NL and with higher apoB and apoB/apoAI in HC (p<0.05). HC individuals carrying c.1050C allele carriers (CC and CT genotypes) had lower change of total cholesterol, LDL-c, apoB and apoB/apoAI ratio (p<0.05) than the TT genotype carriers in response to atorvastatin. CONCLUSION: The SCARB1 polymorphisms are related with variations in serum lipids in the Brazilian population and c.1050C>T SNP is associated with lipid-lowering atorvastatin response.

Arritimias cardíacas em idosos saudáveis: detecçäo através da eletrocardiografia dinâmica / Cardiac arrhythmias in healthy elderly: detection through dynamic electrocardiography

Com o objetivo de avaliar a ocorrência de arritmias em idosos considerados "normais" do ponto de vista cardiovascular, foram estudados, através da eletrocardiografia dinâmica de 24 horas, 50 gerontes, com idades de 65 a 82 anos (média = 73,1), 44 do sexo masculino. Consideraram-se critérios de inclusäo: ausência de sintomas relacionados ao aparelho cardiovascular, de arritmias ao exame rotineiro, de bulhas acessórias e sopros; pressäo arterial sistólica menor do que 160 mmHg e diastólicas inferior a 95 mmHg. O ritmo era sinusal em todos os casos e as freqüências cardíacas mínimas variaram de 45 a 75 bpm (médio = 60,9) e as máximas de 60 a 150 bpm (média = 79,8). O intervalo PR variou de 0,10 a 0,24 s (média = 0,17); em apenas um caso era maior que 0,20. Em 30 casos (60%) foram evidenciadas arritmias cardíacas: extra-sístoles ventriculares (EV), em 22, extra-sístoles supraventriculares (ESV), em 16, e Wolff-Parkinson-White transitório, em um. As EV eram unifocais em 14 casos e polifocais em 8. Apresentavam-se isoladas em 20 casos, sendo freqüentes (> 6 EV/min) em um, e bigeminadas (curta duraçäo) em 2. As EVS eram unificais em 13 casos e polifocais em dois; isoladas em 13 casos e freqüentes em cinco; em dois casos havia bigeminismo de curta duraçäo e, em outro, episódios fugazes de taquicardia paroxística supraventricular. Näo houve registro de alteraçöes do segmento ST em nenhum caso. Esses resultados indicam que indivíduos idosos, assintomáticos e sem evidência de cardiopatia, podem apresentar arritmias relativamente freqüentes quanto avaliados pela ECD de 24 horas. Entretanto, o real significado desses achados e a necessidade de tratamento medicamentoso profilático näo estäo ainda adequadamente estabelecidos

Comparação entre lovastatina e o gemfibrozil no tratamento de hiperlipidemias primárias / Comparison between lovastatin and gemfibrozil in treatment of primary hyperlipidemias

Purpose - To compare the effects of lovastatin and gemfibrozil in patients with primary hyperlipidemias. Patients and Methods - Forty patients with cholesterolemia over 200 mgldl and triglyceridemia not higher than 350 mp/dl, excluded secondary causes, were selected. Twenty patients received lovastatin and 20 gemfibrozil. In order to establish the lipid profile, blood samples were taken after 2 months without medication, after 4 weeks of diet and placebo and after 6 and 12 weeks active treatment. Biochemic profile was determined before and after the treatment with active drug. Results - Thirty nine patients completed the study. Total and LDL-cholesterol were significantly reduced (p < 0.05) by both drugs but lovastatin had greater effect. Only gemfibrozil reduced triglycerides significantly. Neither drug had significant effects on HDL-cholesterol. The tolerance was satisfactory; only one patient (using gemfibrozil) needed to stop the treatment due to gastrointestinal side effects. The biochemic profïle did not present any significant alteration. Conclusion - Both drugs produced useful effects on the lipid profile. Lovastatin produced greater reductions of total and LDL-cholesterol, while gemfibrozil was more active reducing triglycerides. Neither drug changed significantly the HDL-cholesterol