Screening for naturally occurring apolipoprotein A-I variants: apo A-I(ΔK107) is associated with low HDL-cholesterol levels in men but not in women

Isoelectric focussing (IEF) in carrier ampholyte-generated pH gradients and hybrid isoelectric focussing (HIEF) in immobilized pH gradients under nondenaturing conditions were used in parallel to screen 5,500 plasma samples for naturally occurring variants of apolipoprotein A-I (apo A-I). The following defects were identified in four unrelated subjects heterozygous for apo A-I variants: apo A-I(K107)(2 ×), apo A-I(K107M)(1 ×), and apo A-I(E41R)(1 ×). The later variant is a novel finding. Family studies did not reveal any association of apo A-I(K107M) and apo A-I(E41R) with dyslipidemia, but identified several heterozygotes for apo A-I(K107) who had low levels of high density lipoprotein (HDL)cholesterol. Therefore, and since the apo A-I(K107) is the most frequent apo A-I variant in Germany (1 5,000) we evaluated our data and that reported from 11 families with 32 heterozygous carriers and 30 unaffected controls. This analysis revealed that apo A-I(K107) is associated with lower HDL-cholesterol (-30%) and higher triglycerides (+ 48%) in men but not in women as compared with unaffected family members as well as with controls from the Prospective Cardiovascular Münster (PROCAM) study. Moreover, 11 of 15 male apo AI(K107) heterozygotes but only 2 of 17 female apo AI(K107) heterozygotes had HDL-cholesterol levels below the 20th percentile of sex-matched controls from the PROCAM study. We conclude that heterozygosity for apo A-I(K107) decreases HDL-cholesterol and increases triglycerides in men but not in women.     

Optimization of a diagnostic platform for oxidation–reduction potential (ORP) measurement in human plasma

Objectives: Oxidation–reduction potential (ORP) measurement can demonstrate the extent of oxidative stress in patients with severe illness and/or injury. A novel ORP diagnostic platform using disposable sensors (RedoxSYS) has been validated by comparison to mass spectrometry, but the optimal methods of sample handling for best performance of the device have not been described.

Methods: We sought to optimize ORP measurement in human plasma under controlled conditions. We hypothesized that the anticoagulant, freeze–thawing, and storage duration would influence measured ORP levels.

Results: The platform was sensitive to exogenous oxidation with hydrogen peroxide and reduction with ascorbic acid. Plasma anticoagulated with heparin was more sensitive to differences in ORP than plasma prepared in citrate. ORP measurements decreased slightly after a freeze–thaw cycle, but once frozen, ORP was stable for up to one month.

Discussion: We confirm that ORP detects oxidative stress in plasma samples. Optimal measurement of plasma ORP requires blood collection in heparin anticoagulant tubes and immediate analysis without a freeze–thaw cycle.     

Heterochromatin protein (HP)1γ is not only in the nucleus but also in the cytoplasm interacting with actin in both cell compartments

Confocal and electron microscopy images, and WB analysis of cellular fractions revealed that HP1γ is in the nucleus but also in the cytoplasm of C2C12 myoblasts, myotubes, skeletal and cardiac muscles, N2a, HeLa and HEK293T cells. Signal specificity was tested with different antibodies and by HP1γ knockdown. Leptomycin B treatment of myoblasts increased nuclear HP1γ, suggesting that its nuclear export is Crm-1-dependent. HP1γ exhibited a filamentous pattern of staining partially co-localizing with actin in the cytoplasm of myotubes and myofibrils. Immunoelectron microscopic analysis showed high-density immunogold particles that correspond to HP1γ localized to the Z-disk and A-band of the sarcomere of skeletal muscle. HP1γ partially co-localized with actin in C2C12 myotubes and murine myofibrils. Importantly, actin co-immunoprecipitated with HP1γ in the nuclear and cytosolic fractions of myoblasts. Actin co-immunoprecipitated with HP1γ in myoblasts incubated in the absence or presence of the actin depolymerizing agent cytochalasin D, suggesting that HP1γ may interact with G-and F-actin. In the cytoplasm, HP1γ was associated to the perinuclear actin cap that controls nuclear shape and position. In the nucleus, re-ChIP assays showed that HP1γ-actin associates to the promoter and transcribed regions of the house keeping gene GAPDH, suggesting that HP1γ may function as a scaffold protein for the recruitment of actin to control gene expression. When HP1γ was knocked-down, myoblasts were unable to differentiate or originated thin myotubes. In summary, HP1γ is present in the nucleus and the cytoplasm interacting with actin, a protein complex that may exert different functions depending on its subcellular localization.     

Hypomethylation of the thymosin β(10) gene is not associated with its overexpression in non-small cell lung cancer

Lung cancer is the leading cause of cancer-related deaths worldwide and is usually associated with a late diagnosis and a poor prognosis. Thymosin β₁₀ (TMSB10) is a monomeric actin sequestering protein that regulates actin cytoskeleton organization. The aberrant TMSB10 expression has been implicated in the pathogenesis of human cancers. However, its role in carcinogenesis is still controversial. To better understand the role of TMSB10 in lung tumorigenesis and its regulatory mechanism, we examined the methylation status and expression of the TMSB10 gene in non-small cell lung cancers (NSCLCs) using methylation-specific PCR (MSP) and immunohistochemistry (IHC), respectively. MSP analysis showed that the TMSB10 promoter was already unmethylated in most tumor tissues and became demethylated in 20 (14.4%) of the 139 NSCLCs. TMSB10 hypomethylation was not significantly correlated with the clinicopathological features. IHC showed that the TMSB10 protein was strongly expressed in the cytoplasm of malignant cells and its overexpression was detected in 50.0% of the tumor tissues compared to normal tissues. TMSB10 overexpression was frequently observed in sqaumous cell carcinomas compared to adenocarcinomas with border line significance (P = 0.072). However, TMSB10 methylation status was not linked to its overexpression. Collectively, these results suggest that TMSB10 hypomethylation may be a frequent event in NSCLCs, but it may not be a common mechanism underlying TMSB10 overexpression. However, further studies with large numbers of patients are needed to confirm our findings.     

Claudin-11 is over-expressed and dislocated from the blood–testis barrier in Sertoli cells associated with testicular intraepithelial neoplasia in men

In mouse testis, claudin-11 is responsible for the formation of specific parallel TJ strands of the blood–testis barrier (BTB). Concerning the human BTB, there is no information about the transmembrane TJ proteins. We recently demonstrated the loss of functional integrity of the BTB in testicular intraepithelial neoplasia (TIN), associated with a dislocation of the peripheral TJ proteins ZO-1 and ZO-2. Here, we determined the expression and distribution of claudin-11 at the human BTB in seminiferous tubules with normal spermatogenesis (NSP) and TIN. Immunostaining of claudin-11 revealed intense signals at the basal BTB region in seminiferous epithelium with NSP. Within TIN tubules, claudin-11 immunostaining became diffuse and cytoplasmic. Double immunogold labeling demonstrated a co-localization of claudin-11 and ZO-1 at the inter-Sertoli cell junctions. Real-time RT-PCR of laser microdissected tubules showed an up-regulation of claudin-11 mRNA in TIN. Additionally, increased claudin-11 protein was observed by Western blot. We conclude that claudin-11 constitutes a TJ protein at the human BTB. In TIN tubules, claudin-11 is up-regulated and dislocated from the BTB. Therefore, the disruption of the BTB is related to a dysfunction of claudin-11 and not to a failure of its expression.     

A polymorphism in the YWHAH gene encoding 14-3-3 eta that is not associated with sporadic Creutzfeldt–Jakob disease (CJD)

14-3-3 proteins are abundantly expressed in the brain, particularly neuronal tissue and are thought to serve multiple biological functions involved in neuronal development and cell growth and death. Recent studies have shown associations of 14-3-3 genes with neurodegenerative disorders based on their chromosomal linkage to these diseases and to regulatory functions for the nervous system. Although the role of 14-3-3 proteins in the pathogenesis of prion diseases remains unknown, the detection of altered levels of isoforms of the 14-3-3 protein in the cerebrospinal fluid is considered a biomarker for diagnosis of sporadic Creutzfeldt–Jakob disease (sCJD). To identify other susceptibility genes for prion disease, we examined nucleotide variations in YWHAH, a gene encoding 14-3-3 eta. This case–control study included 182 sCJD patients and 206 healthy Koreans. Polymerase chain reaction was used to amplify open reading frame and some 3′-untranslated region (UTR) in exon 2, and direct sequencing was carried out. One polymorphism, 753 G/A, was detected in the 3′-UTR of exon 2 on the YWHAH. The genotype distribution and allele frequencies of the YWHAH 753 G/A polymorphism were not significantly different between controls and sCJD patients. This finding indicates that YWHAH 753 G/A polymorphism is unlikely to be linked to genetic susceptibility or have a modifying effect in sCJD. On analysis stratified by the prion protein gene 129 or 219 genotype, no significant relation was found in genotype and allele frequencies of the YWHAH 753G/A. This is the first genetic association study of YWHAH with sCJD populations.     

RARB and STMN2 polymorphisms are not associated with sporadic Creutzfeldt–Jakob disease (CJD) in the Korean population

Polymorphisms in the prion protein gene (PRNP) can affect the susceptibility of humans to prion diseases. Recently, aside from PRNP, single nucleotide polymorphisms (SNPs) of two candidate genes for susceptibility to human prion diseases have been identified by human genome-wide association studies (GWAS) in the British population. One SNP of retinoic acid receptor beta (RARB), which is correlated with prion disease incubation time in mice, was associated with human prion diseases such as variant and iatrogenic CJD in the British population. The other SNP of the gene that encodes SCG10 (STMN2), which is related to clinical onset of sporadic CJD, was also associated with variant CJD and kuru. In order to investigate whether two polymorphisms located in upstream of RARB and STMN2 are associated with sporadic CJD in the Korean population, we compared genotype and allele frequencies of these polymorphisms in 217 sporadic CJD patients and 216 healthy Koreans. The genotype distribution and allele frequencies in upstream of the RARB and STMN2 polymorphisms were not significantly different between healthy controls and Korean sporadic CJD patients. This finding indicates that the two SNPs are not correlated with genetic susceptibility to sporadic CJD in the Korean population. This is the first genetic association study of RARB and STMN2 with sporadic CJD in an Asian population.     

Supplementation of Merino ewes with vitamin E plus selenium increases α-tocopherol and selenium concentrations in plasma of the lamb but does not improve their immune function

Vitamin E and selenium have been reported to improve immune function across a range of species. Ewes lambing on poor-quality dry pasture in autumn in Western Australia are at risk of being deficient in vitamin E and selenium at lambing thus predisposing their lambs to deficiencies and increasing the risk of infection and disease. This study tested the hypotheses that (i) supplementation of autumn-lambing ewes with vitamin E plus selenium in late gestation will increase the concentrations of vitamin E and selenium in plasma in the ewe and lamb and (ii) that the increased concentrations of vitamin E and selenium in plasma in the lambs will improve their innate and adaptive immune responses and thus survival. Pregnant Merino ewes were divided into a control group (n=58) which received no supplementation or a group supplemented with vitamin E plus selenium (n=55). On days 111, 125 and 140 of pregnancy ewes in the vitamin E plus selenium group were given 4 g all-rac-α-tocopherol acetate orally. On day 111 the ewes were also given 60 mg of selenium as barium selenate by subcutaneous injection. The concentrations of α-tocopherol and selenium were measured in ewes and/or lambs from day 111 of pregnancy to 14 weeks of age±10 days (weaning). Immune function of the lamb was assessed by analysing the numbers and phagocytic capacities of monocytes and polymorphonuclear leucocytes and plasma IgG and anti-tetanus toxoid antibody concentrations between birth and 14 weeks of age±10 days. Maternal supplementation with vitamin E plus selenium increased the concentration of α-tocopherol in plasma (1.13 v. 0.67 mg/l; P<0.001) and selenium in whole blood (0.12 v. 0.07 mg/l; P<0.01) of the ewes at lambing compared with controls. Supplementation also increased the concentration of α-tocopherol (0.14 v. 0.08 mg/l; P<0.001) and selenium (0.08 v. 0.05 mg/l; P<0.01) in lambs at birth compared with controls. There was no significant effect of supplementation on immune function or survival in the lambs.     

Hepatic and plasma sex differences in saturated and monounsaturated fatty acids are associated with differences in expression of elongase 6, but not stearoyl-CoA desaturase in Sprague–Dawley rats

Monounsaturated fatty acids (MUFA) have been viewed as either beneficial or neutral with respect to health; however, recent evidence suggests that MUFA may be associated with obesity and cardiovascular disease. Sex differences in MUFA composition have been reported in both rats and humans, but the basis for this sexual dimorphism is unknown. In the current study, enzymes involved in MUFA biosynthesis are examined in rat and cell culture models. Male and female rats were maintained on an AIN-93G diet prior to killing at 14 weeks of age after an overnight fast. Concentrations of 16:0 (2,757 ± 616 vs. 3,515 ± 196 μg fatty acid/g liver in males), 18:1n-7 (293 ± 66 vs. 527 ± 49 μg/g) and 18:1n-9 (390 ± 80 vs. 546 ± 47 μg/g) were lower, and concentrations of 18:0 (5,943 ± 1,429 vs. 3,987 ± 325 μg/g) were higher in phospholipids in livers from female rats compared with males. Hepatic elongase 6 mRNA and protein were 5.9- and 2.0-fold higher, respectively, in females compared with males. Stearoyl-CoA desaturase expression did not differ. Specific hormonal effects were examined in HepG2 cells cultured with varying concentrations of 17β-estradiol, progesterone and testosterone (0, 10, 30 and 100 nM) for 72 h. Progesterone and 17β-estradiol treatments increased, while testosterone decreased, elongase 6 protein. Sex differences in MUFA composition were associated with increased expression of hepatic elongase 6 in females relative to male rats, which appears to be mediated by sex hormones based on observations of hormonal treatments of HepG2 cells.     

Why is the reduction of NO in cytochrome c dependent nitric oxide reductase (cNOR) not electrogenic?

The membrane-bound enzyme cNOR (cytochrome c dependent nitric oxide reductase) catalyzes the reduction of NO in a non-electrogenic process. This is in contrast to the reduction of O₂ in cytochrome c oxidase (CcO), the other member of the heme-copper oxidase family, which stores energy by the generation of a membrane gradient. This difference between the two enzymes has not been understood, but it has been speculated to be of kinetic origin, since per electron the NO reduction is more exergonic than the O₂ reduction, and the energy should thus be enough for an electrogenic process. However, it has not been clear how and why electrogenicity, which mainly affects the thermodynamics, would slow down the very exergonic NO reduction. Quantum chemical calculations are used to construct a free energy profile for the catalytic reduction of NO in the active site of cNOR. The energy profile shows that the reduction of the NO molecules by the enzyme and the formation of N₂O are very exergonic steps, making the rereduction of the enzyme endergonic and rate-limiting for the entire catalytic cycle. Therefore the NO reduction cannot be electrogenic, i.e. cannot take electrons and protons from the opposite sides of the membrane, since it would increase the endergonicity of the rereduction when the gradient is present, thereby increasing the rate-limiting barrier, and the reaction would become too slow. It also means that proton pumping coupled to electron transfer is not possible in cNOR. In CcO the corresponding rereduction of the enzyme is very exergonic.     

IL-1ra anti-inflammatory cytokine polymorphism is associated with risk of gastric cancer and chronic gastritis in a Brazilian population, but the TNF-β pro-inflammatory cytokine is not

Genetic polymorphisms in genes that codify inflammatory cytokines have been associated with gastric carcinogenesis. This study evaluated polymorphisms IL-1RN VNTR and TNFB+252A/G in a population from Southeast Brazil with regard to the risk of chronic gastritis and gastric cancer and the presence of an association of gastric lesions with risk factors such as gender, age, smoking, drinking and Helicobacter pylori infection. In this case-control study, polymorphism at IL-1RN VNTR was investigated using the allele-specific polymerase chain reaction method, while the polymerase chain reaction-restriction fragment length polymorphism technique was used to identify the TNFB+252A/G genotype in 675 Brazilian individuals [229 with chronic gastritis (CG), 200 with gastric cancer (GC) and 246 healthy individuals as controls (C)]. Multiple logistic regression analysis (log-additive, dominant, and recessive models) have not showed association of the genotype frequencies for the SNP TNFB + 252A/G with risk of CG or GC. However, as for IL-1RN VNTR it was observed significant differences in all three analysis models, with higher values of OR in recessive model, both in the GC group (OR = 3.04, 95% CI = 1.41-6.56, p < 0.01) and CG (OR = 2.32, 95% CI = 1.10-4.90, p = 0.02) compared to the C group. In addition, the multiple logistic regression showed also an association with risk factors such as male gender, older age and alcohol intake regarded GC group. So, our results indicated that the IL-1RN*2 allele may increase the risk of gastric cancer and precancerous lesions in the Southeast Brazilian population, reinforcing the importance of host genetic factors in the susceptibility to gastric cancer and the participation of cytokines in both the inflammation and the carcinogenic process.     

Confinement of β(1)- and β(2)-adrenergic receptors in the plasma membrane of cardiomyocyte-like H9c2 cells is mediated by selective interactions with PDZ domain and A-kinase anchoring proteins but not caveolae

The sympathetic nervous system regulates cardiac output by activating adrenergic receptors (ARs) in cardiac myocytes. The predominant cardiac ARs, β(1)- and β(2)AR, are structurally similar but mediate distinct signaling responses. Scaffold protein-mediated compartmentalization of ARs into discrete, multiprotein complexes has been proposed to dictate differential signaling responses. To test the hypothesis that βARs integrate into complexes in live cells, we measured receptor diffusion and interactions by single-particle tracking. Unstimulated β(1)- and β(2)AR were highly confined in the membrane of H9c2 cardiomyocyte-like cells, indicating that receptors are tethered and presumably integrated into protein complexes. Selective disruption of interactions with postsynaptic density protein 95/disks large/zonula occludens-1 (PDZ)-domain proteins and A-kinase anchoring proteins (AKAPs) increased receptor diffusion, indicating that these scaffold proteins participate in receptor confinement. In contrast, modulation of interactions between the putative scaffold caveolae and β(2)AR did not alter receptor dynamics, suggesting that these membrane domains are not involved in β(2)AR confinement. For both β(1)- and β(2)AR, the receptor carboxy-terminus was uniquely responsible for scaffold interactions. Our data formally demonstrate that distinct and stable protein complexes containing β(1)- or β(2)AR are formed in the plasma membrane of cardiomyocyte-like cells and that selective PDZ and AKAP interactions are responsible for the integration of receptors into complexes.     

Examination of structural changes in the transforming growth factor β receptor 1 (TGFβR1) gene in patients with chronic heart failure

We examined nine exons of transforming growth factor β receptor type 1 (TGFβR1) gene in patients with chronic heart failure with different types of heart remodelling. We identified two missense mutations (c.457G>A (p.V1531) and c.1285A>C (p.Y229S)) and two synonym substitutions (c.1125A>C (p.Y377Y) and c.516A>G (p.S172S)), as well as polymorphisms at splicing site c.1024+24G>A (rs334354). Substitutions c.1285A>C (p.Y229S) and c.516A>G (p.S172S) were not previously described.     

Nitrite correlates with 3-nitrotyrosine but not with the F2-isoprostane 15(S)-8-iso-PGF2α in urine of rheumatic patients

In vitro studies suggested that nitrite may play a cytoprotective role in inflammation. The aim of the present clinical study was to investigate the relationship between the NO metabolites nitrite and nitrate and the biomarkers of oxidative stress 3-nitrotyrosine (3-NT) and 15(S)-iso-PGF_2α in patients suffering from chronic inflammatory rheumatic diseases. In morning urine from 28 patients with different chronic inflammatory rheumatic diseases (23–82 years of age) and from 41 healthy persons of both genders, nitrite and nitrate were quantitated by GC-MS, and 3-NT and 15(S)-iso-PGF_2α by GC-MS/MS. Mean creatinine-corrected urinary excretion rates of nitrite (1.1 versus 0.19 μmol/mmol, P = 0.00012) and 3-NT (1.2 versus 0.39 nmol/mmol, P = 0.01629), but not of nitrate (105 versus 106 μmol/mmol), were significantly elevated in rheumatism as compared to health. Urinary excretion rate of 15(S)-iso-PGF_2α did not differ between patients and healthy subjects (65 versus 69 pmol/mmol creatinine, P = 0.48). In rheumatism, urinary 3-NT correlated closely with nitrite (R = 0.788, P < 0.0001) and moderately with nitrate (R = 0.45, P < 0.016), but did not correlate with 15(S)-iso-PGF_2α (R = ?0.083, P = 0.68). In healthy persons there was no correlation between urinary 3-NT and nitrite or nitrate. Our study suggests that urinary nitrite may represent a novel specific biomarker of nitrative stress in chronic inflammatory rheumatic disease. In another eight patients with chronic inflammatory rheumatic diseases we found higher nitrite concentrations in synovial fluid as compared to serum (1.30 versus 0.35 μM). We hypothesize that in chronic inflammatory rheumatic diseases nitrite concentration is elevated in the inflamed joint and contributes to the inactivation of myeloperoxidase-catalyzed production of hypochloric acid by forming nitryl chloride which eventually nitrates tyrosine to form 3-NT.     

A SNP in the 5′ flanking region of the myostatin-1b gene is associated with harvest traits in Atlantic salmon (Salmo salar)

Background

Myostatin (MSTN) belongs to the transforming growth factor-β superfamily and is a potent negative regulator of skeletal muscle development and growth in mammals. Most teleost fish possess two MSTN paralogues. However, as a consequence of a recent whole genome-duplication event, salmonids have four: MSTN-1 (?1a and -1b) and MSTN-2 (?2a and -2b). Evidence suggests that teleost MSTN plays a role in the regulation of muscle growth. In the current study, the MSTN-1b gene was re-sequenced and screened for SNP markers in a commercial population of Atlantic salmon. After genotyping 4,800 progeny for the discovered SNPs, we investigated their association with eight harvest traits - four body-weight traits, two ratios of weight traits, flesh colour and fat percentage - using a mixed model association analysis.

Results

Three novel SNPs were discovered in the MSTN-1b gene of Atlantic salmon. One of the SNPs, located within the 5′ flanking region (g.1086C?>?T), had a significant association with harvest traits (p?<?0.05), specifically for: Harvest Weight (kg), Gutted Weight (kg), Deheaded Weight (kg) and Fillet Weight (kg). The haplotype-based association analysis was consistent with this result because the two haplotypes that showed a significant association with body-weight traits, hap4 and hap5 (p?<?0.05 and p?<?0.01, respectively), differ by a single substitution at the g.1086C?>?T locus. The alleles at g.1086C?>?T act in an additive manner and explain a small percentage of the genetic variation of these phenotypes.

Conclusions

The association analysis revealed that g.1086C?>?T had a significant association with all body-weight traits under study. Although the SNP explains a small percentage of the variance, our results indicate that a variation in the 5′ flanking region of the myostatin gene is associated with the genetic regulation of growth in Atlantic salmon.

     

Angiotensin (1–7) does not interact directly with MAS1, but can potently antagonize signaling from the AT1 receptor

Angiotensin (1–7) has been reported to be a ligand for the GPCR MAS1. Small molecule MAS1 modulators have also been recently characterized. Aside from convincing evidence for MAS1 activation of Gq signaling, little is known about MAS1 mediated signaling pathways initiated by these ligands, especially Ang (1–7). We performed a comprehensive characterization of recombinant MAS1 signaling induced by Ang (1–7) and small molecule ligands through numerous G protein-dependent and independent pathways, and in a signaling pathway agnostic approach. We find that small molecule ligands modulate numerous G protein-dependent and independent pathways through MAS1, including Gq and Gi pathways, GTPγS binding, β-arrestin recruitment, Erk1/2 and Akt phosphorylation, arachidonic acid release, and receptor internalization. Moreover, in dynamic mass redistribution (DMR) assays that provide a pathway-agnostic readout of cellular responses, small molecule agonists produced robust responses. In contrast, Ang (1–7) failed to induce or block signaling in any of these assay platforms. We detected specific binding of radiolabeled Ang (1–7) to rat aortic endothelial cell (RAEC) membranes, but not to recombinant MAS1. Biphasic, concentration-dependent biased signaling responses to Ang II were detected in RAEC. These phases were associated with vastly different DMR characteristics and this likely provides a molecular basis for previously observed concentration-dependent divergent physiological actions of Ang II. Both phases of Ang II signaling in RAECs were potently inhibited by Ang (1–7), providing a plausible molecular mechanism for Ang (1–7) as counter regulator of the Ang II- AT1 axis, responsible at least in part for Ang (1–7) physiological activities.     

The T29C polymorphism of the transforming growth factor-β1 (TGF-β1) gene is associated with genetic susceptibility to acute coronary syndrome in Mexican patients

Inflammation plays an essential role in the development and progression of atherosclerotic lesions, and plaque disruption. The TGF-β1 plays an important role in the anti-inflammatory process. The aim of the present study was to evaluate the role of TGF-β1 gene polymorphisms as susceptibility markers for acute coronary syndrome (ACS). Two polymorphisms (TGF-β -509T>C and TGF-β T29C) of the TGF-β gene were analyzed by 5' exonuclease TaqMan genotyping assays in a group of 426 patients with coronary acute syndrome and 551 healthy unrelated controls. A significant difference was observed in the distribution of TGF-β T29C polymorphism between ACS patients and healthy controls (P<10(-3)). According to the co-dominant model, individuals with the TGF-β 29 TT genotype have a 2.5-fold increased risk of developing ACS (P<10(-3)). Multiple logistic analysis showed that the largest risk factor for developing ACS was given by smoking habit, diabetes, hypertension, dyslipidemia, and the TGF-β1 29 TT genotype. The analysis of linkage disequilibrium showed one haplotype (TT) with increased frequency and one haplotype (CC) with decreased frequency in ACS patients when compared to healthy controls. The results suggest that TGF-β1 T29C gene polymorphism could be involved in the risk of developing ACS in Mexican individuals.     

Mutation in the beta3 subunit of Guanine nucleotide-binding protein (GNB3) gene is not associated with Type II diabetes mellitus risk: a case–control study of a North Indian population

Context: Genetics play a major role in development and pathophysiology of Type 2 diabetes mellitus (T2DM).

Objective: To asses the association of Guanine nucleotide-binding protein (GNB3) (C825T) gene's polymorphism with T2DM.

Materials and methods: A case–control study including 400 North Indians was performed using Polymerase Chain Reaction–Restriction Fragment Length Polymorphism (PCR-RFLP) approach to analyze genetic polymorphism.

Results: No significant difference was observed in genotype and allele frequencies of GNB3 gene on comparing cases with controls.

Discussion: Our study is in agreement with studies on Polish, Japanese, Hispanic-American and Danish populations who observed no significant association between GNB3 (C825T) polymorphism and T2DM.

Conclusion: GNB3 (C825T) polymorphism is not associated with T2DM.