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Oxidative stress can modulate blood pressure levels in different models. Xanthine oxidoreductase is one of the enzymes producing free radicals in the cardiovascular system, and it can contribute to the increment of the oxidative stress and, consequently, blood pressure. We analyzed the association between the -337GA and 565+64CT polymorphisms of the xanthine oxidoreductase gene with blood pressure and oxidative stress levels.These polymorphisms were studied in a case-control study (185 patients with hypertension and 385 normotensive controls), we found that these polymorphisms were related to blood pressure levels. This association was high in patients with hypertension and showed an additive effect but did not increase the risk of developing hypertension. We studied an additional and independent sample of patients with hypertension (n=100) to know the association of these polymorphisms with oxidative stress levels.We found that these polymorphisms were related to blood pressure levels. This association was high in hypertensive patients and showed an additive effect, but does not increase the risk of developing hypertension. We have found that the same alleles related with higher blood pressure-337A and 565+64C were related with increased oxidative stress in patients with hypertension.Our results suggest that polymorphisms -337GA and 565+64CT of xanthine oxidoreductase gene are related with blood pressure and oxidative stress in hypertension, adding evidence to the role of xanthine oxidoreductase and oxidative stress in blood pressure. [ABSTRACT FROM AUTHOR]

Few data are available on genotype-phenotype interactions among familial hypercholesterolemia (FH) patients in South European populations and there are no data about the influence of R3500Q mutation on lipoprotein phenotype compared to low-density lipoprotein receptor (LDLR) mutations. The objective of the study is to analyze the influence of mutations in the LDLR and apolipoprotein B (apoB) genes on lipoprotein phenotype among subjects clinically diagnosed of FH living in East Spain. In all, 113 FH index patients and 100 affected relatives were studied. Genetic diagnosis was carried out following a protocol based on Southern blot and PCR-SSCP analysis. A total of 118 FH subjects could be classified into three groups according to the type of LDLR mutations (null mutations, missense mutations affecting the ligand binding 3-5 repeat, and missense mutations outside this domain). In addition, the lipoprotein phenotype of these FH groups was compared with 19 heterozygous subjects with familial ligand-defective apoB (FDB), due to R3500Q mutation. FH patients carrying missense mutations affecting the ligand binding repeat 3-5 showed total and LDL cholesterol levels significantly higher than FH patients with missense mutations in other LDLR domains or FDB patients. FH subjects carrying null mutations showed lower high-density lipoprotein cholesterol plasma values compared to FH carrying missense mutations. FDB subjects showed the lowest total and LDL cholesterol plasma values. In conclusion, the type of LDLR gene mutation and R3500Q mutation influences the lipoprotein phenotype of FH population from East Spain.European Journal of Human Genetics (2003) 11, 959-965. doi:10.1038/sj.ejhg.5201079 Published online 24 September 2003 [ABSTRACT FROM AUTHOR]

• A renewed interest exists in miRNAs as biomarkers in cardiovascular disease. • miR-126–3p is associated with albuminuria, a marker of endothelial dysfunction, in hypertension. • High miR-126–3p levels are associated with cardiovascular events in general population. Endothelial dysfunction is a forerunner of atherosclerosis, leading to cardiovascular disease, and albuminuria is a marker of endothelial dysfunction. Circulating levels of microRNAs are emerging as potential biomarkers for cardiovascular disease. Here we estimate the predictive value of a plasma microRNAs signature associated with albuminuria in the incidence of cardiovascular events. Plasma microRNAs quantified in hypertensive patients by next generation sequencing were validated in a cohort of patients and controls by real-time quantitative PCR. The microRNAs found to be associated with albuminuria were analysed for their prognostic value in predicting cardiovascular events incidence on a retrospective, population-based study (Hortega Study), using Cox proportional hazard models. A plasma microRNA profile was identified in the discovery cohort (n = 48) associated with albuminuria and three microRNAs (miR-126–3p, miR-1260b and miR-374a-5p) were confirmed in the validation cohort (n = 98). The microRNA signature discriminates urinary albumin excretion at baseline (n = 1025), and predicts the incidence of cardiovascular events and coronary heart disease and stroke in a general population retrospective study within a 14-year follow-up (n = 926). High miR-126–3p levels were associated with a shorter time free of both cardiovascular events (HR=1.48, (1.36–1.62), p < 0.0001), as well as coronary artery disease and stroke combined (HR=2.49, (2.19–2.83), p < 0.0001). An increased plasma microRNAs profile was identified in hypertensive patients with albuminuria. Increased miR-126–3p suggest it may serve as a prognostic marker for cardiovascular events in a long-term general population. Further studies will assess the potential role of miR-126–3p as a guide for the status of endothelial dysfunction. Circulating miR-126–3p as a prognostic marker of MACE and combined CAD and stroke in a long-term general population cohort. A signature of 4 miRNAs is associated with albuminuria in the discovery and validation cohorts of hypertensive patients and controls. in a general population cohort (Hortega testing cohort) followed during 14 years, increased levels of plasma circulating miR-126–3p are associated with the incidence of MACE (major adverse cardiovascular events) and combined CAD (coronary artery disease) and stroke. [Display omitted] [ABSTRACT FROM AUTHOR]

The potential use of oxidative stress products as disease markers and progression is an important aspect of biomedical research. In the present study, the quantification of urine 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dG) concentration has been used to express the oxidation status of hypertensive subjects. 8-oxo-dG has been simultaneously isolated and assayed in nuclear (nDNA) and mitochondrial DNA (mtDNA). In addition, oxidative stress of mononuclear cells has been estimated by means of GSH and GSSG levels and GSSG/GSH ratio in hypertensive subjects before and after antihypertensive treatment. It is shown that oxidative stress decreases significantly in hypertensive patients after treatment the effect being accompanied by reduction of their blood pressure. A significant correlation is observed comparing the yield of urine 8-oxo-dG and that isolated from mitochondria DNA. Moreover, urinary excretion of 8-oxo-dG also correlates with the GSSG/GSH ratio of cells. Conclusion: urine 8-oxo-dG assay is a good marker for monitoring oxidative stress changes in hypertensives. [ABSTRACT FROM AUTHOR]

Kidney injury in hypertension and diabetes entails, among in other structures, damage in a key cell of the glomerular filtration barrier, the podocyte. Podocytes are polarized and highly differentiated cells in which vesicular transport, partly driven by Rab GTPases, is a relevant process. The aim of the present study was to analyze Rab GTPases of the Rab-Rabphilin system in human immortalized podocytes and the impact of high glucose and angiotensin II. Furthermore, alterations of the system in urine cell pellets from patients with hypertension and diabetes were studied. Apoptosis was analyzed in podocytes, and mRNA level quantification, Western blot analysis, and immunofluorescence were developed to quantify podocyte-specific molecules and Rab-Rabphilin components (Rab3A, Rab27A, and Rabphilin3A). Quantitative RTPCR was performed on urinary cell pellet from patients. The results showed that differentiated cells had reduced protein levels of the Rab-rabphillin system compared with undifferentiated cells. After glucose overload and angiotensin II treatment, apoptosis was increased and podocyte-specific proteins were reduced. Rab3A and Rab27A protein levels were increased under glucose overload, and Rabphilin3A decreased. Furthermore, this system exhibited higher levels under stress conditions in a manner of angiotensin II dose and time treatment. Immunofluorescence imaging indicated different expression patterns of podocyte markers and Rab27A under treatments. Finally, Rab3A and Rab27A were increased in patient urine pellets and showed a direct relationship with albuminuria. Collectively, these results suggest that the Rab-Rabphilin system could be involved in the alterations observed in injured podocytes and that a mechanism may be activated to reduce damage through the vesicular transport enhancement directed by this system. [ABSTRACT FROM AUTHOR]

Background: Sequencing of miRNAs isolated from exosomes has great potential to identify novel disease biomarkers, but exosomes have low amount of RNA, hindering adequate analysis and quantification. Here, we have assessed several steps in developing an optimized small RNA (sRNA) library preparation protocol for next-generation sequencing (NGS) miRNA analysis from urinary exosomes.Methods: A total of 24 urinary exosome samples from donors were included in this study. RNA was extracted by column-based methods. The quality of extracted RNA was assessed by spectrophotometric quantification and Bioanalyzer software analysis. All libraries were prepared using the CleanTag small RNA library preparation protocol and the effect of our additional modifications on adapter-dimer presence, sequencing data and tagged small RNA library population was also analyzed.Results: Our results show that good quality sequencing libraries can be prepared following our optimized small RNA library preparation protocol from urinary exosomes. When the size selection by gel purification step was included within the workflow, adapter-dimer was totally removed from cDNA libraries. Furthermore, the inclusion of this modification step within small RNA library protocol augmented the small RNA mapped reads, with an especially significant 37% increase in miRNA reads, and the gel purification step made no difference to the tagged miRNA population.Conclusions: This study provides researchers with an optimized small RNA library preparation workflow for next generation sequencing based exosome-associated miRNA analysis that yields a high amount of miRNA mapped reads without skewing the tagged miRNA population significantly. [ABSTRACT FROM AUTHOR]

Background We aimed to determine if immune-unreactive albumin excretion (IURAE) is associated with cardiovascular (CV) events in a representative sample of a general population from Spain. Methods We included 1297 subjects (mean age ± standard error 48.0 ± 0.2 years, 48% females), who participated in the Hortega Follow-Up Study. The primary endpoint was incidence of fatal and non-fatal CV events. Urinary albumin excretion (UAE) was measured in spot voided urine, frozen at –80°C, by immunonephelometry [immune-reactive albumin excretion (IRAE)] and by high-performance liquid chromatography (HPLC) [total albumin excretion (AE)]. IURAE was calculated as the difference between HPLC measurements and IRAE. We estimated fully adjusted hazard ratios (HRs) of CV incidence by Cox regression for IRAE, IURAE and total AE. Results After an average at-risk follow-up of 13 years, we observed 172 CV events. urinary albumin to creatinine ratio (UACR) of ≥30 mg/g assessed by IRAE, IURAE or total AE concentrations was observed in 74, 273 and 417 participants, respectively. Among discordant pairs, there were 49 events in those classified as micro- and macroalbuminuric by IURAE, but normoalbuminuric by IRAE. Only the IRAE was a significant independent factor for the incidence of CV events [HR (95% confidence interval) 1.15 (1.04–1.27)]. The association of UAE with CV events was mainly driven by heart failure (HF) [HR 1.33 (1.15–1.55) for IRAE; HR 1.38 (1.06–1.79) for IURAE; HR 1.62 (1.22–2.13) for total AE]. Those subjects who were micro- and macroalbuminuric by both IRAE and IURAE had a significant increase in risk for any CV event, and especially for HF. Conclusions IRAE, IURAE and AE were associated with an increased risk for CV events, but IRAE offered better prognostic assessment. [ABSTRACT FROM AUTHOR]

Identifying new markers of disease flares in lupus nephritis (LN) that facilitate patient stratification and prognosis is important. Therefore, the aim of the present study was to analyze whether urinary SIRT1 expression was altered in LN and whether SIRT1 values in urine could be valuable biomarker of disease activity. In a cohort study, urinary pellets from 40 patients diagnosed with systemic lupus erythematosus (SLE) were analyzed. Clinical measures of lupus activity were assessed. The expression of SIRT1 was quantified by quantitative PCR (qRT-PCR) and immunoblot, then compared between patients with active lupus nephritis, in remission and healthy controls. Association with lupus activity and renal histological features was also analyzed. A significant increase in SIRT1 mRNA levels in patients with active LN was observed compared with those in remission (P=0.02) or healthy controls (P=0.009). In addition, SIRT-1 protein levels were also augmented in LN group than remission (P=0.029) and controls (P=0.001). A strong association was found between SIRT1 expression with anti-dsDNA in SLE and in patients with LN. In addition, histological features in LN biopsies were related with SIRT1, increasing its expression in proliferative forms. Finally, SIRT1 expression values showed a strong discriminatory power of renal injury in SLE. Our study demonstrated an altered urinary expression of SIRT1 and a strong association with disease activity in LN patients, being a valuable marker of renal injury. These results showed the role of the SIRT1 pathway in the SLE pathogenesis. [ABSTRACT FROM AUTHOR]

Background: The possibility of integrating viral vectors to become a persistent part of the host genome makes them a crucial element of clinical gene therapy. However, viral integration has associated risks, such as the unintentional activation of oncogenes that can result in cancer. Therefore, the analysis of integration sites of retroviral vectors is a crucial step in developing safer vectors for therapeutic use. Results: Here we present VISMapper, a vector integration site analysis web server, to analyze next-generation sequencing data for retroviral vector integration sites. VISMapper can be found at: http://vismapper.babelomics.org. Conclusions: Because it uses novel mapping algorithms VISMapper is remarkably faster than previous available programs. It also provides a useful graphical interface to analyze the integration sites found in the genomic context. [ABSTRACT FROM AUTHOR]

Background. Currently, renal biopsy remains the gold standard for the diagnosis and prognosis of lupus nephritis (LN). However, it is an invasive method, and new non-invasive laboratory tests are needed to identify renal involvement without renal biopsy. Podocyte damage plays an important role in the pathogenesis and progression of systemic lupus erythematosus (SLE). We characterize whether the phenotype of urinary podocytes (viability, apoptosis, mRNA and protein levels of the podocyteassociated molecules) is a novel marker of clinical and histological features in SLE patients with or without LN. Methods. We quantified in urinary sediments of 32 SLE patients and 20 controls, mRNA and protein levels of podocalyxin, synapotopodin, podocin, nephrin andWT-1 by quantitative real-time polymerase chain reaction and western blot analysis and correlated thesewith clinical and histological parameters. The viability of detached urine podocytes was analysed by flow cytometry with podocalyxin and annexin V/7-AAD double staining and immunofluorescence of urine podocyte cultures. Results. The degree of a poptotic podocytes from urine samples was significantly decreased in patients with LN, especially in the active state (33% compared with 75% in controls, P < 0.001), and the majority of the detached podocytes in the urine of patients with active LN were viable (70% grew in culture). Furthermore, urinary mRNA of podocyte-associated molecules was significantly lower in patients with active LN (P < 0.05) compared with healthy controls, and protein levels of podocyte markers were significantly increased in SLE patients, especially with LN compared with SLE without LN (P < 0.05) and the healthy control group (P < 0.01). Finally, urinary protein levels of podocyte-related markers were associated with proteinuria and histological features (P < 0.05 and P < 0.01), and receiver operating characteristics curves of protein levels discriminate between LN and healthy controls with an area under the curve (AUC) between 0.91 and 0.77 (P < 0.001). Conclusions. Urinary dedifferentiated podocytes were shown in active LN, and their protein levels correlated with proteinuria and histological features in LN. These preliminary results suggest that it could be a potentially useful non-invasive marker for evaluating the progression of glomerular disease in SLE. [ABSTRACT FROM AUTHOR]

Background and Aims Familial hypercholesterolemia (FH) is associated with higher levels of inflammatory mediators such as chemokines, which contribute to an increased risk of premature atherosclerosis in these patients. We studied the response of chemokines related to early atherosclerotic processes during an oral unsaturated fat load test (OFLT) in patients with heterozygous FH and compared this response to normolipidemic and normoglycemic subjects. Methods Blood samples were taken from 12 FH patients and 20 healthy controls with a similar age, gender distribution, and body mass index. Plasma chemokine levels were determined in both groups in a fasting state and at 2, 4, 6, and 8 h after an OFLT using human cytokine multiplex kits (Linco) and a Luminex LABScan™100 system. Results In the fasting state MIP-1β, MIP-1α, IP-10, IFN-γ, MCP-1, and IL-8 were significantly increased in the FH group compared to the healthy controls ( p <0.05). In addition, a significant decrease in postprandial chemokine plasma values were found in the FH group compared to fasting values after the OFLT. In normolipidemic nondiabetic controls no significant changes were found in the postprandial state. Conclusions There was a postprandial decrease in chemokines related to early atherosclerotic processes after an OFLT in FH patients. These results confirm the influence of dietary patterns in this group of patients. [ABSTRACT FROM AUTHOR]

There is increased interest in using microRNAs (miRNAs) as biomarkers in different diseases. Present in body fluids, it is controversial whether or not they are mainly enclosed in exosomes, thus we studied if urinary miRNAs are concentrated inside exosomes and if the presence of systemic lupus erythematosus with or without lupus nephritis modifies their distribution pattern. We quantified specific miRNAs in urine of patients with systemic lupus erythematosus (n = 38) and healthy controls (n = 12) by quantitative reverse-transcription PCR in cell-free urine, exosome-depleted supernatant and exosome pellet obtained by ultracentrifugation. In control group, miR-335* and miR-302d were consistently higher in exosomes than in exosome-depleted supernatant, and miR-200c and miR-146a were higher in cell-free fraction. In lupus patients, all urinary miRNAs tested were mainly in exosomes with lower levels outside them (p<0.05 and p<0.01, respectively). This pattern is especially relevant in patients with active lupus nephritis compared to the control group or to the SLE patients in absence of lupus nephritis, with miR-146a being the most augmented (100-fold change, p<0.001). Among the exosomal miRNAs tested, only the miR-146a discriminates the presence of active lupus nephritis. In conclusion, urinary miRNAs are contained primarily in exosomes in systemic lupus erythematosus, and the main increment was found in the presence of active lupus nephritis. These findings underscore the attractiveness of exosomal miRNAs in urine, a non-invasive method, as potential renal disease markers. [ABSTRACT FROM AUTHOR]

Background Alterations in the redox balance are involved in the origin, promotion and progression of cancer. Inter-individual differences in the oxidative stress regulation can explain a part of the variability in cancer susceptibility. Purpose: The aim of this study was to evaluate if polymorphisms in genes codifying for the different systems involved in oxidative stress levels can have a role in susceptibility to breast cancer. Methods We have analyzed 76 single base polymorphisms located in 27 genes involved in oxidative stress regulation by SNPlex technology. First, we have tested all the selected SNPs in 493 breast cancer patients and 683 controls and we have replicated the significant results in a second independent set of samples (430 patients and 803 controls). Gene-gene interactions were performed by the multifactor dimensionality reduction approach. Results Six polymorphisms rs1052133 (OGG1), rs406113 and rs974334 (GPX6), rs2284659 (SOD3), rs4135225 (TXN) and rs207454 (XDH) were significant in the global analysis. The gene-gene interactions demonstrated a significant four-variant interaction among rs406113 (GPX6), rs974334 (GPX6), rs105213 (OGG1) and rs2284659 (SOD3) (p-value = 0.0008) with high-risk genotype combination showing increased risk for breast cancer (OR = 1.75 [95% CI; 1.26-2.44]). Conclusions The results of this study indicate that different genotypes in genes of the oxidant/antioxidant pathway could affect the susceptibility to breast cancer. Furthermore, our study highlighted the importance of the analysis of the epistatic interactions to define with more accuracy the influence of genetic variants in susceptibility to breast cancer. [ABSTRACT FROM AUTHOR]

Objectives Familial hypercholesterolemia (FH) is characterized by increased oxidative stress (OS) levels. In the postprandial state, lipids and lipoproteins modulate OS status through their impact on pro-oxidant and antioxidant mechanisms. The objective of this study was to evaluate in patients with FH the response to an unsaturated oral fat load test (OFLT) by analyzing the mRNA levels of genes involved in the glutathione and thioredoxin antioxidant systems. Design and Methods We analyzed 14 FH patients and 20 normolipidemic and normoglycemic controls. In both groups, mRNA values of antioxidant enzyme genes (glutathione and thioredoxin systems) were determined at baseline and at 2, 4, 6, and 8 h after OFLT by real time PCR. Results In the fasting state the mRNA levels of antioxidant enzymes GPX4 and the GSR, GSS, and GCLC enzymes (involved in glutathione regeneration and synthesis) and thioredoxin (TXN), were significantly increased in the FH group compared to the healthy controls. Some genes (GPX1 and GPX4) were increased at 4 h in both groups, but values for the rest of the antioxidant enzyme mRNAs were decreased in FH patients after 4 h from unsaturated OFLT and were increased in controls. Conclusions We concluded that an OFLT with predominantly unsaturated fat has a different effect on postprandial antioxidant enzyme mRNA levels in controls than in FH patients. Increased antioxidant enzyme mRNA is not the main way to reduce postprandial oxidative stress in FH. This difference could determine the influence of dietary patterns in these patients. [ABSTRACT FROM AUTHOR]

Background: Alterations in the redox balance are involved in the origin, promotion and progression of cancer. Inter-individual differences in the oxidative stress regulation can explain a part of the variability in cancer susceptibility. The aim of this study was to evaluate if polymorphisms in genes codifying for the different systems involved in oxidative stress levels can have a role in susceptibility to breast cancer. Methods: We have analyzed 76 single base polymorphisms located in 27 genes involved in oxidative stress regulation by SNPlex technology. First, we have tested all the selected SNPs in 493 breast cancer patients and 683 controls and we have replicated the significant results in a second independent set of samples (430 patients and 803 controls). Gene-gene interactions were performed by the multifactor dimensionality reduction approach. Results: Six polymorphisms rs1052133 (OGG1), rs406113 and rs974334 (GPX6), rs2284659 (SOD3), rs4135225 (TXN) and rs207454 (XDH) were significant in the global analysis. The gene-gene interactions demonstrated a significant four-variant interaction among rs406113 (GPX6), rs974334 (GPX6), rs105213 (OGG1) and rs2284659 (SOD3) (p-value = 0.0008) with high-risk genotype combination showing increased risk for breast cancer (OR = 1.75 [95% CI; 1.26-2.44]). Conclusions: The results of this study indicate that different genotypes in genes of the oxidant/antioxidant pathway could affect the susceptibility to breast cancer. Furthermore, our study highlighted the importance of the analysis of the epistatic interactions to define with more accuracy the influence of genetic variants in susceptibility to breast cancer. [ABSTRACT FROM AUTHOR]

Background The objective was to investigate the association between BMI and single nucleotide polymorphisms previously identified of obesity-related genes in two Spanish populations. Forty SNPs in 23 obesity-related genes were evaluated in a rural population characterized by a high prevalence of obesity (869 subjects, mean age 46yr, 62% women, 36% obese) and in an urban population (1425 subjects, mean age 54yr, 50% women, 19% obese). Genotyping was assessed by using SNPlex and PLINK for the association analysis. Results Polymorphisms of the FTO were significantly associated with BMI, in the rural population (beta 0.87, p-value <0.001). None of the other SNPs showed significant association after Bonferroni correction in the two populations or in the pooled analysis. A weighted genetic risk score (wGRS) was constructed using the risk alleles of the Tag-SNPs with a positive Beta parameter in both populations. From the first to the fifth quintile of the score, the BMI increased 0.45 kg/m2 in Hortega and 2.0 kg/m2 in Pizarra. Overall, the obesity predictive value was low (less than 1%). Conclusion The risk associated with polymorphisms is low and the overall effect on BMI or obesity prediction is minimal. A weighted genetic risk score based on genes mainly acting through central nervous system mechanisms was associated with BMI but it yields minimal clinical prediction for the obesity risk in the general population. [ABSTRACT FROM AUTHOR]

• SNP in oxidative stress-related genes are crucial in osteoporotic bone fracture. • rs4077561 TXNRD1 SNP was the principal genetic risk factor associated with fracture. • Genetic factors are crucial in the etiopathogenesis of osteoporosis complications. The most widely accepted etiopathogenesis hypothesis of the origin of osteoporosis and its complications is that they are a consequence of bone aging and other environmental factors, together with a genetic predisposition. Evidence suggests that oxidative stress is crucial in bone pathologies associated with aging. The aim of this study was to determine whether genetic variants in oxidative stress-related genes modified the risk of osteoporotic fracture. We analysed 221 patients and 354 controls from the HORTEGA sample after 12–14 years of follow up. We studied the genotypic and allelic distribution of 53 SNPs in 24 genes involved in oxidative stress. The results showed that being a carrier of the variant allele of the SNP rs4077561 within TXNRD1 was the principal genetic risk factor associated with osteoporotic fracture and that variant allele of the rs1805754 M6PR , rs4964779 TXNRD1 , rs406113 GPX6 , rs2281082 TXN2 and rs974334 GPX6 polymorphisms are important genetic risk factors for fracture. This study provides information on the genetic factors associated with oxidative stress which are involved in the risk of osteoporotic fracture and reinforces the hypothesis that genetic factors are crucial in the etiopathogenesis of osteoporosis and its complications. [ABSTRACT FROM AUTHOR]

Eur J Clin Invest 2011 Abstract Background Increased accumulation of fat results from an imbalance between energy expenditure and intake, being modulated by different environmental and genetic factors. Uncoupling proteins (UCPs) are mitochondrial carrier proteins able to spend energy generating heat. Therefore, variations in these genes are good candidates as potential modulators of body fat accumulation. Our aim was to investigate the possible association of genetic variations of the gene codifying the UCP2 protein with obesity and fat distribution. Design We performed a cross-sectional study in 2367 individuals from two population-based studies from different regions of Spain. The Hortega Study included 1436 individuals (693 women) 21-85 years old, and the Pizarra Study included 931 individuals (584 women) 18-65 years old. We evaluated three polymorphisms of the UCP2 gene. Results The TT genotype of the rs660339 polymorphism and the AA genotype of the rs659366 polymorphism of the UCP2 gene were significantly associated with higher waist circumference in the Hortega Study. Furthermore, subjects carrying both genotypes (TT+AA) also showed higher central adiposity compared with other genotypes. This association was also present in the Pizarra Study. Moreover, in the pooled population, we found a stronger association with waist circumference. Even, we found association with BMI. Furthermore, rs659366 polymorphism was associated with the risk of abdominal obesity ( P = 0·04: OR = 1·3; CI = 1·01-1·67). Conclusions Polymorphisms of the UCP2 gene (rs660339 and rs659366) were associated with central obesity. This study shows association between the UCP2 gene and the susceptibility to obesity and body fat distribution in a south European population. [ABSTRACT FROM AUTHOR]

The objective of the study was to evaluate oxidative stress (OS) status in subjects with different cardiovascular risk factors. With this in mind, we have studied three models of high cardiovascular risk: hypertension (HT) with and without metabolic syndrome, familial hypercholesterolemia (FH) and familial combined hyperlipidemia (FCH) with and without insulin resistance. Oxidative stress markers (oxidized/reduced glutathione ratio, 8-oxo-deoxyguanosine and malondialdehide) together with the activity of antioxidant enzyme triad (superoxide dismutase, catalase, glutathione peroxidase) and activation of both pro-oxidant enzyme (NAPDH oxidase components) and AGTR1 genes, as well as antioxidant enzyme genes (CuZn-SOD, CAT, GPX1, GSR, GSS and TXN) were measured in mononuclear cells of controls (n = 20) and patients (n = 90) by assessing mRNA levels. Activity of some of these antioxidant enzymes was also tested. An increase in OS and pro-oxidant gene mRNA values was observed in patients compared to controls. The hypertensive group showed not only the highest OS values, but also the highest pro-oxidant activation compared to those observed in the other groups. In addition, in HT a significantly reduced antioxidant activity and mRNA induction of antioxidant genes were found when compared to controls and the other groups. In FH and FCH, the activation of pro-oxidant enzymes was also higher and antioxidant ones lower than in the control group, although it did not reach the values obtained in hypertensives. The thioredoxin system was more activated in patients as compared to controls, and the highest levels were in hypertensives. The increased oxidative status in the presence of cardiovascular risk factors is a consequence of both the activation of pro-oxidant mechanisms and the reduction of the antioxidant ones. The altered response of the main cytoplasmic antioxidant systems largely contributes to OS despite the apparent attempt of the thioredoxin system to control it. [ABSTRACT FROM AUTHOR]

Background: The elongase of long chain fatty acids family 6 (ELOVL6) is an enzyme that specifically catalyzes the elongation of saturated and monounsaturated fatty acids with 12, 14 and 16 carbons. ELOVL6 is expressed in lipogenic tissues and it is regulated by sterol regulatory element binding protein 1 (SREBP-1). Objective: We investigated whether ELOVL6 genetic variation is associated with insulin sensitivity in a population from southern Spain. Design: We undertook a prospective, population-based study collecting phenotypic, metabolic, nutritional and genetic information. Measurements were made of weight and height and the body mass index (BMI) was calculated. Insulin resistance was measured by homeostasis model assessment. The type of dietary fat was assessed from samples of cooking oil taken from the participants' kitchens and analyzed by gas chromatography. Five SNPs of the ELOVL6 gene were analyzed by SNPlex. Results: Carriers of the minor alleles of the SNPs rs9997926 and rs6824447 had a lower risk of having high HOMA_IR, whereas carriers of the minor allele rs17041272 had a higher risk of being insulin resistant. An interaction was detected between the rs6824447 polymorphism and the intake of oil in relation with insulin resistance, such that carriers of this minor allele who consumed sunflower oil had lower HOMA_IR than those who did not have this allele (P = 0.001). Conclusions: Genetic variations in the ELOVL6 gene were associated with insulin sensitivity in this population-based study. [ABSTRACT FROM AUTHOR]

Familial hypercholesterolaemia (FH) is an autosomal dominant disease characterized by elevated levels of low-density lipoprotein-cholesterol (LDL-C). Phenotypic expression is highly variable, being influenced by diet, age, gender, body mass index, apolipoprotein E genotype and type of LDL-receptor gene mutation. Microsomal triglyceride (TG) transfer protein (MTP) is a protein involved in lipid metabolism. Polymorphism MTP -493 GT has been shown to modulate lipid levels in several populations. To analyse the effect of this polymorphism in the lipid phenotype expression of FH and treatment response, we studied a sample of 222 Spanish FH patients, of whom 147 were studied before and after treatment with 20 mg of atorvastatin daily during 6 weeks. The variant was analysed by polymerase chain reaction amplification and single-strand confirmation polymorphism. Treatment reduced LDL-C, total cholesterol and TGs. Baseline fasting TGs and very-low-density lipoprotein cholesterol levels were lower in female T allele carriers (TG: 111±51 mg/dl GG, 89±35 mg/dl GT, 83±26 mg/dl TT, P=0.022; very-low-density lipoprotein cholesterol: 24±13 mg/dl GG, 16±5 mg/dl GT, 17±5 mg/dl TT, P=0.018). Triglyceride response to atorvastatin was modulated by this polymorphism in men (P=0.009), but not in women, although differences between genotypes were maintained after treatment. In conclusion, the MTP -493 GT polymorphism modulates pre- and post-treatment plasma TG values of FH in Spanish subjects in a gender-specific way. Other environmental and genetic factors likely also modulate this response. [ABSTRACT FROM AUTHOR]

Osteoporosis is the most common bone disorder worldwide and is associated with a reduced quality of life with important clinical and economic consequences. The most widely accepted etiopathogenic hypothesis on the origin of osteoporosis and its complications is that they are a consequence of the synergic action of environmental and genetic factors. Bone is constantly being remodelled through anabolic and catabolic pathways in which inflammation, the NF-kB pathway and the renin-angiotensin-aldosterone system (RAAS) are crucial. The aim of our study was to determine whether polymorphisms in genes implicated in inflammation, the NF-kB pathway and RAAS modified the risk of osteoporotic fracture. We analysed 221 patients with osteoporotic fracture and 354 controls without fracture from the HORTEGA sample after 12–14 years of follow up. In addition, we studied the genotypic distribution of 230 single nucleotide polymorphisms (SNPs) in genes involved in inflammation, NF-kB pathway and RAAS. Our results showed that be carrier of the C allele of the rs2228145 IL6R polymorphism was the principal genetic risk factor associated with osteoporotic fracture. The results also showed that variant genotypes of the rs4762 AGT , rs4073 IL8 , rs2070699 END1 and rs4291 ACE polymorphisms were important genetic risk factors for fracture. The study provides information about the genetic factors associated with inflammation, the NF-kB pathway and RAAS, which are involved in the risk of osteoporotic fracture and reinforces the hypothesis that genetic factors are crucial in the etiopathogenesis of osteoporosis and its complications. • Genetic factors are crucial in the osteoporotic fracture. • Inflammation gene polymorphisms are associated with osteoporotic fracture. • NF-kB pathway gene polymorphisms are associated with osteoporotic fracture. • RAAS gene polymorphisms are associated with osteoporotic fracture. [ABSTRACT FROM AUTHOR]

Aim To determine the association between serum levels of high-sensitivity C-reactive protein (hs- CRP) and the incidence of type 2 diabetes in a prospective cohort from southern Spain ( Pizarra study). Materials and methods The study formed part of the Pizarra cohort study, a prospective study started in 1995 with a follow-up of 11 years. Anthropometric and metabolic variables were measured at baseline and at 6 years and 11 years of follow-up . All subjects underwent an oral glucose tolerance test. Serum levels of TNFα and its receptors, hs- CRP, IL-6, leptin, adiponectin and FABP4 were measured at 6 years of follow-up. Results After adjusting for age, sex and obesity, subjects with levels of hs- CRP> 2.9 mg/L in the second study (2003-4) had a higher risk of developing type 2 diabetes by the third study (2008-9) ( OR = 7.97; 95% CI = 1.72-36.89; P = 0.008), and subjects with adiponectin levels > 13.2 mg/L had a lower risk of developing type 2 diabetes ( OR = 0.23, P = 0.02). High values of hs- CRP and high values of adiponectin were associated positively ( OR = 8.26; 95% CI = 1.84-37.19; P = 0.006) and negatively ( OR = 0.17; 95% CI = 0.04-0.69; P = 0.01), respectively, with the risk of having Hb A1c ≥ 6.5% at 11 years of follow-up. Conclusions Subjects with high serum hs- CRP levels and low serum adiponectin levels have a higher risk of developing type 2 diabetes within five years. [ABSTRACT FROM AUTHOR]

The objective of the study was to evaluate oxidative stress (OS) status in subjects with different cardiovascular risk factors. With this in mind, we have studied three models of high cardiovascular risk: hypertension (HT) with and without metabolic syndrome, familial hypercholesterolemia (FH) and familial combined hyperlipidemia (FCH) with and without insulin resistance. Oxidative stress markers (oxidized/reduced glutathione ratio, 8-oxo-deoxyguanosine and malondialdehide) together with the activity of antioxidant enzyme triad (superoxide dismutase, catalase, glutathione peroxidase) and activation of both pro-oxidant enzyme (NAPDH oxidase components) and AGTR1 genes, as well as antioxidant enzyme genes (CuZn-SOD, CAT, GPX1, GSR, GSS and TXN) were measured in mononuclear cells of controls (n = 20) and patients (n = 90) by assessing mRNA levels. Activity of some of these antioxidant enzymes was also tested. An increase in OS and pro-oxidant gene mRNA values was observed in patients compared to controls. The hypertensive group showed not only the highest OS values, but also the highest pro-oxidant activation compared to those observed in the other groups. In addition, in HT a significantly reduced antioxidant activity and mRNA induction of antioxidant genes were found when compared to controls and the other groups. In FH and FCH, the activation of pro-oxidant enzymes was also higher and antioxidant ones lower than in the control group, although it did not reach the values obtained in hypertensives. The thioredoxin system was more activated in patients as compared to controls, and the highest levels were in hypertensives. The increased oxidative status in the presence of cardiovascular risk factors is a consequence of both the activation of pro-oxidant mechanisms and the reduction of the antioxidant ones. The altered response of the main cytoplasmic antioxidant systems largely contributes to OS despite the apparent attempt of the thioredoxin system to control it. [ABSTRACT FROM AUTHOR]

Background: There is increasing interest in using extracellular vesicle-derived microRNAs (miRNAs) as biomarkers in renal dysfunction and injury. Preliminary evidence indicates that miRNAs regulate the progression of glomerular disease. Indeed, exosomes from the renal system have provided novel evidence in the clinical setting of albuminuria. Thus, the aim of this study was to quantify the urinary miRNAs present in exosome and microvesicles (MVs), and to assess their association with the presence of increased urinary albumin excretion in essential hypertension.Methods: Exosomes were collected from urine specimens from a cohort of hypertensive patients with (n = 24) or without albuminuria (n = 28), and from 20 healthy volunteers as a control group. Urinary exosomes were phenotyped by Western blot, tunable resistive pulse sensing, and electronic microscopy. Expression of miR-146a and miR-335* was analysed by qRT-PCR and any associations between albuminuria and exosomal miRNAs were analysed.Results: Urinary miRNAs are highly enriched in exosome subpopulations compared to MVs, both in patients with or without increased albuminuria (p < 0.001), but not in the control group. High albuminuria was associated with 2.5-fold less miR-146a in exosomes (p = 0.017), whereas miR-146a levels in MV did not change. In addition, exosome miR-146a levels were inversely associated with albuminuria (r = 0.65, p < 0.0001), and discriminated the presence of urinary albumin excretion presence [area under the curve = 0.80, 95% confidence interval: 0.66-0.95; p = 0.0013].Conclusions: Our results indicate that miRNAs were enriched in the urinary exosome subpopulation in hypertensive patients and that low miR-146a expression in exosomes was associated with the presence of albuminuria. Thus, urinary exosome miR-146a may be a potentially useful tool for studying early renal injury in hypertension. [ABSTRACT FROM AUTHOR]