Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.6.1.44 (AGT)
 770 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An association between preeclampsia (PE) and a common missense mutation of the methylenetetrahydrofolate reductase gene (MTHFR), a C to T substitution at nucleotide 677 (C677T), which converts an alanine to a valine residue, has been reported in Italian and Japanese populations. We examined 101 cases of hypertension in pregnancy (HP), including 73 cases of PE, and 215 normal pregnancy controls to confirm the association in Japanese women. No significant differences of the frequency of the T677 allele frequency or percentage of T677 homozygotes were detected among the various types of cases: HP (0.38, 12%, respectively), severe HP (0. 40, 12%), PE (0.38, 11%), severe PE (0.41, 11%), primiparous HP (0. 40, 12%), primiparous PE (0.44, 18%), nonelderly HP (0.39, 13%), nonelderly PE (0.40, 14%), nonobese HP (0.38, 12%), nonobese PE (0. 39, 10%), HP without homozygous T235 of the angiotensinogen gene (TT of AGT) (0.38, 15%), PE without TT of AGT (0.38, 15%), and controls (0.38, 15%). The results indicate that T677 of MTHFR may not be a risk factor for PE in Japanese population.
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PMID:Absence of association between a common mutation in the methylenetetrahydrofolate reductase gene and preeclampsia in Japanese women. 1086 14

Several association studies of candidate genes for preeclampsia and essential hypertension have led to discordant results, partly because of small sample sizes. Using a large population-based sample of pregnant women, we conducted an association study of 10 polymorphisms in 9 genes and aimed (1) to validate 10 published associations with preeclampsia or essential hypertension, (2) to investigate candidate polymorphisms previously associated with preeclampsia for association with essential hypertension and similarly with polymorphisms previously associated with essential hypertension. From a prospective sample of 3391 nulliparous French Canadian pregnant women, we identified 180 cases of preeclampsia, 203 cases of essential hypertension that were matched with normotensive control subjects (n=310 and 357, respectively). Polymorphisms were genotyped by allele-specific PCR. Among our candidate polymorphisms, the Met allele of Thr174Met of AGT was associated with preeclampsia (P=0.0033). Haplotype analysis revealed that the A-Met-Thr (G1035A-Thr174Met-Met235Thr) haplotype was associated with a 2.1-fold increased risk of preeclampsia (95% CI, 1.4 to 3.4; P=0.0008). In conclusion, we observed a strong association between a specific AGT haplotype and preeclampsia in our population, without replicating previous published associations with either preeclampsia or essential hypertension. Our data support a role for AGT in genetic susceptibility to preeclampsia.
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PMID:Implication of an AGT haplotype in a multigene association study with pregnancy hypertension. 1463 22

Members of the cytochrome P450 3A subfamily catalyze the metabolism of endogenous substrates, environmental carcinogens, and clinically important exogenous compounds, such as prescription drugs and therapeutic agents. In particular, the CYP3A4 and CYP3A5 genes play an especially important role in pharmacogenetics, since they metabolize >50% of the drugs on the market. However, known genetic variants at these two loci are not sufficient to account for the observed phenotypic variability in drug response. We used a comparative genomics approach to identify conserved coding and noncoding regions at these genes and resequenced them in three ethnically diverse human populations. We show that remarkable interpopulation differences exist with regard to frequency spectrum and haplotype structure. The non-African samples are characterized by a marked excess of rare variants and the presence of a homogeneous group of long-range haplotypes at high frequency. The CYP3A5*1/*3 polymorphism, which is likely to influence salt and water retention and risk for salt-sensitive hypertension, was genotyped in >1,000 individuals from 52 worldwide population samples. The results reveal an unusual geographic pattern whereby the CYP3A5*3 frequency shows extreme variation across human populations and is significantly correlated with distance from the equator. Furthermore, we show that an unlinked variant, AGT M235T, previously implicated in hypertension and pre-eclampsia, exhibits a similar geographic distribution and is significantly correlated in frequency with CYP3A5*1/*3. Taken together, these results suggest that variants that influence salt homeostasis were the targets of a shared selective pressure that resulted from an environmental variable correlated with latitude.
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PMID:CYP3A variation and the evolution of salt-sensitivity variants. 1549 26

To clarify whether the homozygous deletion (DD) genotype of angiotensin-converting enzyme gene ( ACE) is a genetic risk factor for preeclampsia in Japanese women, we performed ACE genotyping in patients with preeclampsia and healthy pregnant women, and analyzed the relationship between preeclampsia and ACE genotype, taking into account some well-known contributing factors for preeclampsia, such as primiparity, positive family history of hypertension, prepregnancy body mass index < 24, and heterozygosity and homozygosity of T235 (MT+TT) genotypes of the angiotensinogen ( AGT) gene. Among all of the subjects, the frequency of the DD genotype was not different between patients with preeclampsia and controls (16% and 12%, respectively). Regarding primiparity, prepregnancy body mass index < 24, and MT+TT genotypes of AGT, no significant differences in the frequency of the DD genotype of ACE were found between patients with preeclampsia and controls, although in a subgroup positive for family history of hypertension, the frequency of the DD genotype tended to be higher in patients with preeclampsia (25%) than in controls (8%; p = 0.061). Carrying the DD genotype may have some influence on the pathogenesis of preeclampsia, perhaps through effects on placental hypoxia or the interaction of hypertensive disease and atherosclerosis, although this influence may not be strong. Additional studies using a larger number of patients and analyses that include other genetic and environmental factors will be necessary to confirm these results.
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PMID:Insertion/deletion polymorphism of the angiotensin-converting enzyme gene and preeclampsia in Japanese patients. 1605 7

There are controversies in reports on the association of polymorphisms in endothelial nitric oxide synthase, angiotensinogen, angiotensin receptor type 1 and angiotensin-converting enzyme genes with an increased risk of developing preeclampsia. We performed a systematic search of published case-control studies through the PubMed database up to January 2006, and report the results of a meta-analysis of polymorphisms investigated in more than five studies: Glu298Asp in eNOS gene (9 analyses involving 1055 patients and 1788 controls), Met235Thr in AGT gene (13 analyses involving 1128 patients and 2278 controls), and intron 16 insertion-deletion polymorphism in ACE gene (10 analyses involving 1121 patients and 1361 controls). Statistically significant associations with preeclampsia were identified for the Met235Thr/AGT polymorphism: OR 1.65 (95% CI 1.19, 2.29) if the polymorphism is considered under the dominant genetic model, and OR 1.54 (95% CI 1.12, 2.11) under the recessive model. For insertion-deletion/ACE polymorphism, statistical significance was demonstrated when the polymorphism was considered under the recessive model: OR 1.51 (95% CI 1.17, 1.94). No single polymorphism was identified as having a major effect.
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PMID:Genetic polymorphisms in vasoactive genes and preeclampsia: a meta-analysis. 1782 85

Preeclampsia is a major cause of maternal and perinatal mortality and morbidity. Regardless of susceptibility or predisposing conditions and risk factors, the degree of increase in abdominal pressure is directly related to the severity of preeclampsia, particularly in women with hydatidiform mole. When increased abdominal pressure is normalized by delivery, preeclampsia is cured. Recent genetic studies highlighted two leading risk factors for preeclampsia: chronic renal disease and T235 homozygosity for the AGT gene. Thus, while there is increased abdominal pressure in pregnancy, an imbalanced renin angiotensin system and renal injuries lead to a vicious cycle of increasing abdominal pressure and further renal injuries. A hypothesis for the potential participation of pressure in preeclampsia is described and the amelioration of preeclampsia through postural intervention and the possible therapeutic effect of angiotensin is suggested.
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PMID:The potential participation of abdominal pressure in preeclampsia. 2577 15

BACKGROUND This meta-analysis enabled us to obtain a precise estimation of the association between gene polymorphisms on chromosome 1 (MTHFR, AGT, F5, IL-10, LEPR) and the susceptibility to pre-eclampsia (PE) in order to reach a uniform conclusion. MATERIAL AND METHODS Web of Science, PubMed, EMBASE, Cochran Library (CENTRAL), and Chinese databases (Chinese National Knowledge Infrastructure-CNKI and Wan Fang) were electronically searched to select relevant studies for this meta-analysis. We selected 95 case-control studies investigating 5 genes (MTHFR, AGT, F5, IL-10, and LEPR) with 8 SNPs. Odds ratios (OR) with their 95% confidence intervals (CI) were used for estimating the association. RESULTS A total of 16 646 PE patients and 28 901 normal-pregnancy patients were included in this meta-analysis. The overall results suggested that rs1801133 of MTHFR (OR=1.17, 95% CI: 1.05-1.13) and rs6025 of F5 (OR=1.53, 95%CI: 1.07-2.20) are significantly associated with PE, whereas rs1801131 of MTHFR, rs699 and rs4762 of AGT, rs1800896 and rs1800871 of IL-10, and rs1137101 of LEPR have no significant association with PE. Subgroup analysis by ethnicity revealed that, except for MTHFR rs1801133 and F5 rs6025 in Caucasians, which were significantly associated with an increased risk of PE, none of these SNPs were significantly associated with PE. As suggested by a symmetric funnel plot in conjunction with the Egger's test, there was no significant publication bias in MTHFR rs1801133 (P=0.318) and rs1801131 (P=0.204), F5 rs6025 (P=0.511), LEPR rs1137101 (P=0.511), AGT rs4762 (P=0.215) and rs699 (P=0.482), IL-10 rs1800871 (P=0.955), and rs1800896 (P=0.144). CONCLUSIONS This meta-analysis provides evidence that MTHFR rs1801133 and F5 rs6025 are associated with an increased risk of PE, especially in Caucasians. However, we do not have sufficient evidence to conclude there is a significant association between other gene polymorphisms and PE.
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PMID:Association Between Gene Polymorphisms on Chromosome 1 and Susceptibility to Pre-Eclampsia: An Updated Meta-Analysis. 2734 38

The study included pregnant women aged 23-41 years with preeclampsia and gestation-associated arterial hypertension at weeks 27-40 and patients with essential arterial hypertension developing under conditions of the metabolic syndrome and without it. Frequency analysis of polymorphisms of the renin-angiotensin system genes (ACE, AGT, and AGTR1), ITGB3, FTO and their associations confirmed the syndrome nature of hypertensive disorders in pregnancy. The presence allele T of AGT gene and/or allele C of AGTR1 gene in the genotype of patients with preeclampsia was associated with higher BP and pressure load over 24 h. Allele D of ACE gene was also essential for BP parameters (pressure load) in patients with preeclampsia and gestation-associated arterial hypertension. Due to high genetic heterogeneity of the preeclampsia syndrome and genetic differences in the incidence of the studied gene polymorphisms in preeclampsia and gestation-associated arterial hypertension, no direct associations between these gestation disorders and polymorphic markers of the renin-angiotensin system genes can be established. However, polymorphisms of the renin-angiotensin system genes are essential for the 24-h dynamics of BP and pressure load under conditions of hypertensive disorders in pregnancy.
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PMID:Distribution of Polymorphisms of the Renin-Angiotensin System Genes (ACE, AGT, and AGTR1), ITGB3, and FTO in Pregnant Patients with Hypertensive Disorders. 3117 47

Background AGT (angiotensinogen) synthesis occurs in renal proximal tubular epithelial cells, independent from systemic AGT , as a component of the intrarenal renin-angiotensin system. We investigated urinary AGT , as a biomarker for renin-angiotensin system activation, and electrolyte concentrations, in relation to glomerular volume, as a proxy for glomerular endotheliosis in renal biopsy tissue from pregnant normotensive control and hypertensive women. Methods and Results Urine samples were collected from normotensive control (n=10), gestational hypertensive (n=6), and pre-eclamptic (n=16) women at the time a renal biopsy was obtained. Samples were collected from Lund University Hospital between November 1999 and June 2001. Urinary AGT , potassium, and sodium were measured, normalized to urinary creatinine. Mean glomerular volume was estimated from biopsy sections. AGT protein expression and localization were assessed in renal biopsies by immunohistochemistry. Urinary AGT concentrations were higher in hypertensive pregnancies (median, gestational hypertension: 11.3 ng/mmol [interquartile range: 2.8-13.6]; preeclampsia: 8.4 ng/mmol [interquartile range: 4.2-29.1]; normotensive control: 0.6 ng/mmol [interquartile range: 0.4-0.8]; P<0.0001) and showed a positive relationship with estimated mean glomerular volume. Urinary potassium strongly correlated with urinary AGT ( P<0.0001). Although numbers were small, AGT protein was found in both glomeruli and proximal tubules in normotensive control but was present only in proximal tubules in women with hypertensive pregnancy. Conclusions This study shows that pregnant women with gestational hypertension or preeclampsia have increased urinary AGT and potassium excretion associated with signs of glomerular swelling. Our data suggest that the kidneys of women with hypertensive pregnancies and endotheliosis have inappropriate intrarenal renin-angiotensin system activation, which may contribute toward the pathogenesis of hypertension and renal injury.
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PMID:Evidence of Augmented Intrarenal Angiotensinogen Associated With Glomerular Swelling in Gestational Hypertension and Preeclampsia: Clinical Implications. 3123 75