Polymorphisms of the renin-angiotensin system are not associated with overweight and obesity in a general adult population

ABSTRACT Objective The increased prevalence of obesity and associated comorbidities, such as cardiovascular and metabolic diseases, has gained attention worldwide, and the renin-angiotensin system (RAS) has been pointed out as a possible link. Thus, the present study aimed to verify the possible association between angiotensinogen (AGT) or angiotensin-converting enzyme (ACE) polymorphisms with overweight and obesity in adults. Subjects and methods The present investigation was a population-based cross-sectional study including 1,567 individuals from an urban area in Brazil. Anthropometric, clinical and biochemical parameters were evaluated, and all individuals were genotyped for the ACE I/D and AGT M/T polymorphisms. Results The prevalence of overweight was higher among men, whereas obesity was more prevalent among women. However, the frequency of ACE or AGT polymorphisms was similar among body mass index (BMI) categories. In addition, the mean age-adjusted BMI averages did not change significantly for ACE or AGT polymorphisms, regardless of sex or BMI category. The age-adjusted BMI average for the combination of ACE and AGT genotypes evidenced no significant differences regardless of sex or BMI categories. Results were similar when BMI was replaced by waist circumference (WC). Conclusions We were not able to find any associations between BMI and WC (overweight/obesity) and ACE and AGT polymorphisms, indicating that the RAS system might not be involved in overweight and obesity, at least based on genetic backgrounds. However, further studies must measure RAS components to elucidate this question.

Association of polymorphisms within the Renin-Angiotensin System with metabolic syndrome in a cohort of Chilean subjects

ABSTRACT Objective Metabolic syndrome (MetS) is associated with hypertension, obesity and dyslipidemia. Thus, genetic variants related with these conditions may modulate its development. We evaluated the effect of polymorphisms in the renin-angiotensin system (RAS) on metabolic syndrome risk in a cohort of Chilean subjects. Subjects and methods A total of 152 subjects, 83 with MetS (51.2 ± 9.6 years) and 69 without MetS (49.5 ± 9.3 years) of both genders were included, according to the ATP III update criteria. The rs4340 Insertion/Deletion (I/D), rs699 (T>C) and rs5186 (A>C) of the ACE, AGT and AGTR1 genes, respectively, were genotyped. Results After adjusting for age and gender, we observed the DD genotype of rs4340 associated with MetS (p = 0.02). Specifically, the DD genotype was associated with MetS risk in women (OR = 4.62, 95%CI, 1.41 – 15.04; p < 0.01). In males, the AA genotype for rs5186 variant was associated with an increased risk for developing MetS when compared with women carrying the same genotype (OR = 3.2; 95%CI, 1.03 – 9.89; p = 0.04). In subjects without MetS, DD genotype was associated with increased waist circumference (p = 0.023) while subjects with MetS carrying the rs5186 TT genotype showed higher levels of HDL-cholesterol (p = 0.031). Conclusion The present study contributes data highlighting the role for RAS polymorphisms in predisposing to metabolic syndrome in Chilean subjects.

Survival and Predictive Factors of Lethality in Hemodyalisis: D/I Polymorphism of The Angiotensin I-Converting Enzyme and of the Angiotensinogen M235T Genes / Sobrevida e Fatores Preditores de Letalidade em Hemodiálise: Polimorfismos D/I do Gene da Enzima Conversora da Angiotensina I e o M235T do Angiotensinogênio

Background: End-stage kidney disease patients continue to have markedly increased cardiovascular disease morbidity and mortality. Analysis of genetic factors connected with the renin-angiotensin system that influences the survival of the patients with end-stage kidney disease supports the ongoing search for improved outcomes. Objective: To assess survival and its association with the polymorphism of renin-angiotensin system genes: angiotensin I-converting enzyme insertion/deletion and angiotensinogen M235T in patients undergoing hemodialysis. Methods: Our study was designed to examine the role of renin-angiotensin system genes. It was an observational study. We analyzed 473 chronic hemodialysis patients in four dialysis units in the state of Rio de Janeiro. Survival rates were calculated by the Kaplan-Meier method and the differences between the curves were evaluated by Tarone-Ware, Peto-Prentice, and log rank tests. We also used logistic regression analysis and the multinomial model. A p value ≤ 0.05 was considered to be statistically significant. The local medical ethics committee gave their approval to this study. Results: The mean age of patients was 45.8 years old. The overall survival rate was 48% at 11 years. The major causes of death were cardiovascular diseases (34%) and infections (15%). Logistic regression analysis found statistical significance for the following variables: age (p = 0.000038), TT angiotensinogen (p = 0.08261), and family income greater than five times the minimum wage (p = 0.03089), the latter being a protective factor. Conclusions: The survival of hemodialysis patients is likely to be influenced by the TT of the angiotensinogen M235T gene. .

Fundamento: Os pacientes em hemodiálise continuam tendo um significativo aumento na morbiletalidade, especialmente a causada por doenças cardiovasculares. A análise dos fatores genéticos ligados ao sistema renina-angiotensina que influenciam na sobrevivência destes pacientes poderá ajudar na busca por melhores resultados. Objetivo: Avaliar a sobrevida em hemodialisados e sua associação com polimorfismo dos genes do sistema reninaangiotensina: deleção/inserção do gene que codifica a enzima conversora da angiotensina I e o M235T do angiotensinogênio. Métodos: Estudo observacional desenhado para ver o papel dos genes do sistema renina-angiotensina. Foram analisados 473 pacientes tratados com hemodiálise crônica em quatro unidades de diálise do Estado do Rio de Janeiro. As taxas de sobrevida foram calculadas pelo método de Kaplan-Meier e as diferenças entre as curvas avaliadas pelos testes de: Tarone-Ware, Peto-Prentice e Log-rank. Foram utilizados também modelos de regressão logística e multinomial. Um valor de p ≤ 0,05 foi considerado estatisticamente significativo. O comitê de ética aprovou este estudo. Resultados: A idade média dos pacientes foi de 45,8%. A taxa de sobrevida global foi de 48% em 11 anos. As principais causas de óbito foram: doenças do aparelho circulatório (34 %) e infecções (15%). A análise de regressão logística encontrou significância estatística para as seguintes variáveis: idade, o TT do angiotensinogênio e a renda familiar acima de cinco salários mínimos, esta última como fator de proteção (p valor: 0,000038, 0,08261 e 0,03089, respectivamente). Conclusões: Nossos dados sugerem que o risco de letalidade em pacientes em hemodiálise pode ser influenciado também pelo polimorfismo ...

Asociación y efectos de interacción en los genes AGT , AGTR1 , ACE , ADRB2 , DRD1 , ADD1, ADD2, ATP2B1, TBXA2R y PTGS2 sobre la hipertensión en la población antioqueña / Association and interaction of AGT, AGTR1, ACE, ADRB2, DRD1, ADD1, ADD2, ATP2B1, TBXA2R and PTGS2 genes on the risk of hypertension in Antioquian population

Introducción. La hipertensión arterial es una enfermedad multifactorial influenciada por componentes genéticos y ambientales, cuya prevalencia varía entre grupos étnicos. Se han llevado a cabo numerosos estudios en genes de sistemas reguladores de la presión arterial, como el sistema renina-angiotensinaaldosterona, el sistema nervioso simpático, los factores endoteliales, y el balance de sodio, mostrando resultados incongruentes entre poblaciones. Objetivos. Evaluar el efecto de variantes en los genes AGT , AGTR1 , ACE , ADRB2 , DRD1 , ADD1 , ADD2 , ATP2B1 , TBXA2R y PTGS2 y del componente ancestral individual, sobre la hipertensión arterial y las cifras de presión arterial en una muestra de población antioqueña. Materiales y métodos. Se genotipificaron 107 casos y 253 controles para 12 variantes en los genes AGT , AGTR1 , ACE , ADRB2 , DRD1 , ADD1 , ADD2 , ATP2B1 , TBXA2R y PTGS2 , y para 20 marcadores informativos de ascendencia. Se evaluó la asociación de los polimorfismos y sus interacciones, y de la composición genética ancestral con hipertensión y cifras de presión arterial. Resultados. Los genes ADD2 , rs4852706 (OR=3,0; p=0,023); DRD1 , rs686 (OR=0,38; p=0,012) y ADRB2 , rs1042718 (OR=10,0; p=0,008); y combinaciones genotípicas de DRD1 con AGTR1 ; de AGT con ADD1 ; y de ADD1 con ATP2B1 y PTGS2 , se asociaron con hipertensión arterial. El componente ancestral amerindio se asoció con disminución en la presión arterial diastólica. Conclusiones. Variantes en los genes ADD2 , DRD1 , ADRB2 , AGTR1 , AGT , ADD1 , ATP2B1 y PTGS2 , individualmente o en su interacción, se encuentran asociadas con hipertensión. El componente ancestral amerindio tiene un efecto sobre las cifras de presión arterial.

Introduction: Hypertension is a multifactorial disease influenced by genetic and environmental components, with its prevalence varying across ethnic groups. Manifold studies on blood pressure regulatory system genes have been carried out -such as the renin-angiotensin-aldosterone system, the sympathetic nervous system, endothelial factor, and sodium balance-, but the results yielded were inconsistent among populations. Objectives: To evaluate the effect of both variants in genes AGT, AGTR1, ACE, ADRB2, DRD1, ADD1, ADD2, ATP2B1, TBXA2R PTGS2, and the result of the individual ancestry component on hypertension and blood pressure levels among population in Antioquia. Methods and materials: 107 cases and 253 controls were genotyped for 12 variants on genes AGT, AGTR1, ACE, ADRB2, DRD1, ADD1, ADD2, ATP2B1, TBXA2R y PTGS2, and for 20 ancestry informative markers. The association of polymorphisms and their interactions, and the association of ancestral genetic composition with hypertension and blood pressure levels were examined. Results: Genes ADD2, rs4852706 (OR=3.0; p=0.023); DRD1, rs686 (OR=0.38; p=0.012) and ADRB2, rs1042718 (OR=10.0; p=0.008); as well as genotypic combinations of DRD1 and AGTR1; AGT and ADD1; and ADD1 to ATP2B1 and PTGS2 were associated to hypertension. The Amerindian ancestry component was associated to some decrease in diastolic blood pressure. Conclusion: Variants on genes ADD2, DRD1, ADRB2, AGTR1, AGT, ADD1, ATP2B1 and PTGS2 individually or interacting, are associated to hypertension. The Amerindian ancestry component has an effect on blood pressure.

Exaggerated blood pressure response during the exercise treadmill test as a risk factor for hypertension

Exaggerated blood pressure response (EBPR) during the exercise treadmill test (ETT) has been considered to be a risk factor for hypertension. The relationship of polymorphisms of the renin-angiotensin system gene with hypertension has not been established. Our objective was to evaluate whether EBPR during exercise is a clinical marker for hypertension. The study concerned a historical cohort of normotensive individuals. The exposed individuals were those who presented EBPR. At the end of the observation period (41.7 months = 3.5 years), the development of hypertension was analyzed within the two groups. Genetic polymorphisms and blood pressure behavior were assessed as independent variables, together with the classical risk factors for hypertension. The I/D gene polymorphism of the angiotensin-converting enzyme and M235T of angiotensinogen were ruled out as risk factors for hypertension. EBPR during ETT is not an independent influence on the chances of developing hypertension. No differences were observed between the hypertensive and normotensive individuals regarding gender (P = 0.655), skin color (P = 0.636), family history of hypertension (P = 0.225), diabetes mellitus (P = 0.285), or hypertriglyceridemia (P = 0.734). The risk of developing hypertension increased with increasing body mass index (BMI) and advancing age. The risk factors, which independently influenced the development of hypertension, were age and BMI. EBPR did not constitute an independent risk factor for hypertension and is probably a preclinical phase in the spectrum of normotension and hypertension.

O polimorfismo AGT*M235T na disfunção cardíaca de etiologia isquêmica aguda: projeto gisca / AGT*M235T polymorphism in acute ischemic cardiac dysfunction: the gisca project

FUNDAMENTO: O polimorfismo AGT*M235T tem sido associado a elevados níveis séricos de angiotensinogênio (AGT), hipertensão arterial sistêmica e disfunção cardíaca (DC). OBJETIVO: Testar a hipótese de haver associação entre polimorfismo AGT*M235T e o risco de desenvolver disfunção cardíaca (insuficiência cardíaca ou disfunção sistólica ventricular esquerda assintomática) pós-síndrome coronariana aguda (SCA), durante o período de internação hospitalar. MÉTODOS: Foram estudados 363 pacientes (idade média 62 ± 12 anos), sendo 233 (64 por cento) homens e 130 (36 por cento) mulheres, todos da mesma coorte, internados por SCA. Compararam-se dados clínicos e genéticos dos 117 (32,2 por cento) que evoluíram com disfunção cardíaca (grupo caso) com os dos 246 (67,8 por cento), que não desenvolveram tal condição (grupo controle). O polimorfismo AGT*M235T foi determinado por análise de sequenciamento e estava em equilíbrio de Hardy-Weinberg. RESULTADOS: Houve diferença significativa na distribuição dos genótipos nas mulheres, com predomínio do genótipo *235MM no grupo controle (p = 0,001) e do alelo *235T no grupo caso. Em ambos os sexos, nos modelos de regressão logística, o diagnóstico de infarto de parede anterior na admissão foi fator de incremento no risco de DC, enquanto angina instável na admissão, ausência do alelo *235T, glicemia < 100 mg/dl, uso de betabloqueador, creatinina sérica < 1,5 mg/dl, faixa de frequência cardíaca > 60 e < 90 bpm e tabagismo atual foram fatores de redução do risco de DC. CONCLUSÃO: Este estudo sugere que a ausência do alelo *235T do AGT contribui para a redução do risco de disfunção cardíaca pós-síndrome coronariana aguda.

BACKGROUND: AGT*M235T polymorphism has been associated with high serum angiotensinogen (AGT) levels, systemic hypertension and cardiac dysfunction (CD). OBJECTIVE: To test the hypothesis of AGT*M235T polymorphism being associated with the risk of developing cardiac dysfunction (heart failure or asymptomatic left ventricular systolic dysfunction) after acute coronary syndrome (ACS) during hospitalization. METHODS: A total of 363 patients (mean age of 62 ± 12 years), of whom 233 (64 percent) were men and 130 (36 percent) were women, all from the same cohort and hospitalized for ACS, were studied. Clinical and genetic data from the 117 (32.2 percent) patients who developed cardiac dysfunction (case group) were compared to those of the 246 (67.8 percent) who did not develop this condition (control group). The AGT*M235T polymorphism was determined by sequence analysis and was in Hardy-Weinberg equilibrium. RESULTS: There was a significant difference in the distribution of genotypes among women, with a predominance of the *235MM genotype in the control group (p = 0.001) and of the *235T allele in the case group. In the logistic regression models, the diagnosis of anterior wall myocardial infarction at admission was related to an increased risk of CD in both genders, whereas unstable angina at admission.; absence of the *235T allele; blood glucose <100 mg/dl; use of betablocker; serum creatinine level < 1.5 mg/dl;heart rate range > 60 and < 90 bpm; and current cigarette smoking were related to a lower risk of CD. CONCLUSION: This study suggests that the absence of the AGT *235T allele contributes to a reduced risk of cardiac dysfunction after acute coronary syndrome.

Hemodynamic, morphometric and autonomic patterns in hypertensive rats - renin-angiotensin system modulation

Background: Spontaneously hypertensive rats develop left ventricular hypertrophy, increased blood pressure and blood pressure variability, which are important determinants of heart damage, like the activation of renin-angiotensin system. AIMS: To investigate the effects of the time-course of hypertension over 1) hemodynamic and autonomic patterns (blood pressure; blood pressure variability; heart rate); 2) left ventricular hypertrophy; and 3) local and systemic Renin-angiotensin system of the spontaneously hypertensive rats. Methods: Male spontaneously hypertensive rats were randomized into two groups: young (n=13) and adult (n=12). Hemodynamic signals (blood pressure, heart rate), blood pressure variability (BPV) and spectral analysis of the autonomic components of blood pressure were analyzed. LEFT ventricular hypertrophy was measured by the ratio of LV mass to body weight (mg/g), by myocyte diameter (ìm) and by relative fibrosis area (RFA, percent). ACE and ACE2 activities were measured by fluorometry (UF/min), and plasma renin activity (PRA) was assessed by a radioimmunoassay (ng/mL/h). Cardiac gene expressions of Agt, Ace and Ace2 were quantified by RT-PCR (AU). Results: The time-course of hypertension in spontaneously hypertensive rats increased BPV and reduced the alpha index in adult spontaneously hypertensive rats. Adult rats showed increases in left ventricular hypertrophy and in RFA. Compared to young spontaneously hypertensive rats, adult spontaneously hypertensive rats had lower cardiac ACE and ACE2 activities, and high levels of PRA. No change was observed in gene expression of Renin-angiotensin system components. Conclusions: The observed autonomic dysfunction and modulation of Renin-angiotensin system activity are contributing factors to end-organ damage in hypertension and could be interacting. Our findings suggest that the management of hypertensive disease must start before blood pressure reaches the highest stable...

[Lack of association between renin-angiotensin system [RAS] polymorphisms and hypertension in Tunisian type 2 diabetics]

The genes encoding renin-angiotensin system [RAS] components are potent candidate genes in both hypertension and diabetes namely ACE encoding the angiotensin converting enzyme and AGT encoding angiotensinogen. It has been suggested that the insertion/deletion [I/D] polymorphism in intron 16 of ACE gene is associated with ACE levels, and M235T gene polymorphism is associated with plasma AGT levels. We examined in this report the association between ACE I/D and AGT M235T polymorphisms with hypertension status in Tunisian type 2 diabetic subjects. Thirty nine hypertensive and 22 normotensive type 2 diabetic Tunisian patients were recruited for this study. The I/D polymorphism of ACE gene was analysed with nested PCR in order to avoid mistyping heterozygous individuals and the M235T polymorphism of AGT gene was analysed using PCR and allele specific restriction. The distribution of DD, ID and II genotypes did not significantly differ between type 2 diabetic patients with or without hypertension [DD: 49%; ID: 41%; II: 10% vs DD: 36%; ID: 55%; II: 9%, respectively] [lasmbda[2]= .06, p=0.5 8]. There was also no significant statistical difference between these two groups for the M235T polymorphism [TT: 20%; MT: 54%; MM: 26% vs TT: 27%; MT: 41%; MM: 32%, respectively] lambda[2]=0.95, p=0.62] RAS polymorphisms do not seem to play a role in the development of hypertension in the studied Tunisian type 2 diabetic subjects

O gene do angiotensinogênio (M235T) e o infarto agudo do miocárdio / The angiotensinogen gene (M235T) and the acute myocardial infarction

OBJETIVO: Estudar o efeito do polimorfismo M235T do gene do angiotensinogênio na doença arterial coronariana e na sua gravidade em pacientes com e sem infarto agudo do miocárdio. MÉTODOS: Estudo transversal com 305 indivíduos de raça branca que foram alocados em 2 grupos. O primeiro com 201 pacientes com doença arterial coronariana comprovada pela angiografia (lesão obstrutiva > 50 por cento), sendo 110 com infarto agudo do miocárdio e 91 sem infarto. O segundo, 104 indivíduos controles com artérias coronárias normais. O polimorfismo M235T do angiotensinogênio foi analisado através da genotipagem pela reação em cadeia da polimerase seguida da digestão pela enzima de restrição. RESULTADOS: A freqüência dos genótipos TT, MT e MM do angiotensinogênio não foi estatisticamente diferente entre os pacientes com doença arterial coronariana e os controles (chi2 = 0,123; p = 0,939) bem como nos grupos de infartados e não infartados (chi2 = 2,171; p = 0,338). O risco relativo de desenvolver doença arterial coronariana e de apresentar infarto analisado entre os genótipos TT vs MM, MT vs MM e TT+MT vs MM não foi significante. A análise da gravidade da doença aterosclerótica no grupo de pacientes com doença arterial coronariana mostrou não haver correlação com os genótipos; resultado semelhante foi encontrado na comparação entre os grupos com e sem infarto. CONCLUSÕES: Não há associação entre o polimorfismo M235T do gene do angiotensinogênio com a doença arterial coronariana, com a sua gravidade e nem com o infarto agudo do miocárdio.

Association of Angiotensin-Converting Enzyme and Angiotensinogen Gene Polymorphisms with Preeclampsia

We tested the hypothesis that angiotensin-converting enzyme (ACE) and angiotensinogen gene polymorphism influence the incidence, development and outcome of preeclampsia. Subjects were recruited from 90 Korean patients with preeclampsia during pregnancy and 98 age-matched controls. After isolation of DNA, polymerase chain reactions (PCR) were carried out to detect polymorphism of the ACE and angiotensinogen. M235T and T174M genotypes of angiotensinogen were determined by digestion with restriction enzyme endonuclease Tth 111-I and NCo I, respectively. The frequency of DD genotype was significantly greater in preeclampsia (0.36) than in controls (0.14) (p<0.05). The frequency of D allele was 0.55 in preeclampsia and 0.40 in controls (p<0.05). There were no differences in the onset of preeclampsia and pregnancy outcomes according to the ACE genotypes. There was no difference in the frequency of a allele of angiotensinogen M235T between the groups (0.79:0.78 in preeclampsia : controls). The frequency of T allele of angiotensinogen T174M gene was slightly increased, but not significantly, in preeclampsia (0.11) than in controls (0.07). In a multivariate analysis, only ACE genotype was associated with the development of preeclampsia (beta=0.27, p=0.05). In conclusion, a molecular variant of ACE, but not angiotensinogen, gene is associated with preeclampsia in Korean women.

Progresión de la poliquistosis renal autosómica dominante. Influencia de polimorfismos de genes de sintasa endotelial del óxido nítrico (ecNOS) y del sistema renina-angiotensina / Progression of autosomic dominant polycystic kidney disease. Influence of endothelial NO synthase (ecNOS) and renin angiotensin system gene polymorphisms

Glomerular filtration rate decline (GFRd) is variable in autosomic dominant polycystic kidney disease (ADPKD). In 88 ADPKD patients, GFRd was assessed by 1/S(Cr) and compared with the association to AT1A1166C (AT1R), AGTM235T (angiotensinogen) and ecNOSGlu298Asp (NO endothelial synthase) polymorphisms. Age at S(Cr) values of 2 and 6 mg/dl were assumed as beginning of progressive phase (A2) and end-stage-renal disease (A6), respectively. Polymorphisms were studied by PCR-RFLP. The group as a whole showed GFRd (ml/min/year) of 6.9+/-0.5; A2 and A6 of 48.9+/-1.3 and 55.0+/-1.4 years and mean arterial pressure of 111.2+/-1.2 mmHg. When A6 was considered, two populations were defined (< or = and > 55 years). In < or = 55 (assumed as PKD1 phenotype) (n=42), A2 and A6 of the AT1 1166CC genotype were 36.0+/-1.2 and 41.4+/-0.9 years vs AA-AC (42.8+/-1.0 and 47.5+/-0.8, p<0.001). A2 and A6 of the ecNOS298Asp/Asp genotype were 34.8+/-1.5 and 41.1+/-0.6 years vs. Glu/Glu-Glu/Asp (42.4+/-0.9 and 47.1+/-0.8, p<0.02). In AGT235TT genotype, GFRd was 12.4+/-2.2 ml/min/year vs MM-MT (7.9+/-0.7, p<0.03). This difference was also observed when all ADPKD patients were considered (TT: 11.02+/-1.5 vs. MM-MT: 6.44+/-0.5 ml/ min/year, p<0.003). AT1 1166CC and ecNOS 298Asp/Asp are associated with earlier A2 and A6 whereas AGT 235TT induce twofold increase in GFRd, suggesting that RAS and ecNOS are involved in ADPKD progression.

La velocidad de progresión (VdP) de la poliquistosis renal autosómica dominante (PQRAD) es variable.Estudiamos la asociación de los polimorfismos AGTM235T (angiotensinógeno), AT1A1166C(ATR1) y ecNOSGlu298Asp (NO sintasa endotelial) con la VdP en 88 pacientes. VdP fue estimada por 1/Crplvs edad. Consideramos edades de Crpl 2 y 6 mg/dl como comienzo de progresión (E2) y arribo a insuficienciarenal crónica terminal (E6), respectivamente. Los polimorfismos se estudiaron por PCR-RFLP. El grupo en sutotalidad presentó VdP (ml/min/año) de 6.9±0.5, E2 y E6 de 48.9±1.3 y 55.0±1.4 años y tensión arterial media(TAM) de 111.2±1.2 mmHg. Según E6 observamos dos grupos (≤ y > a 55 años). En ≤ 55 (fenotipo PKD1,n=42), E2 y E6 del genotipo CC de AT1A1166C fueron 36.0±1.2 y 41.4±0.9 años vs. AA-AC (42.8±1.0 y 47.5±0.8, p < 0.001). E2 y E6 del genotipo ecNOS298Asp/Asp fueron 34.8±1.5 y 41.1±0.6 años vs. Glu/Glu-Glu/Asp (42.4±0.9 y 47.1±0.8, p < 0.02). En el genotipo AGT235TT, la VdP fue 12.4±2.2 ml/min/año vs. MM-MT (7.9±0.7, p < 0.03). Esta diferencia también se observó cuando analizamos todos los pacientes PQRAD (TT: 11.02±1.5 vs. MM-MT: 6.44±0.5 ml/min/año, p < 0.003). Los genotipos AT1 1166CC y ecNOS 298Asp/Asp anticipan E2 y E6 mientras que AGT235TT duplica VdP, sugiriendo la participación del sistema renina angiotensina y NO sintasaendotelial en la progresión de la PQRAD.

Angiotensin converting enzyme I/D, angiotensinogen T174M-M235T and angiotensin II type 1 receptor A1166C gene polymorphisms in Turkish hypertensive patients

Essential hypertension is a multifactorial disease in which genetic and enviromental factors play an important role. These factors differ in each population. As there are no existing data for the Turkish population, we investigated four Renin Angiotensin System (RAS) gene polymorphisms, the angiotensin converting enzyme (ACE), angiotensinogen (AGN) M235T/T174M and angiotensin II type 1 receptor A1166C polymorphism in 109 hypertensive and 86 normotensive Turkish subjects. Polymerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP), and agarose gel electrophoresis tecniques were used to determine these polymorphism. The frequencies of person that carry ACE D allel (DD+ID) was significantly higher in hypertensive group (99.1%) than controls (80%) (P<0.000). M235T TT genotype was also found significantly higher in hypertensives than control group (20% vs 2.7%; P<0.001). The frequency of AGN 174M allele was higher in the hypertensive group than control subjects (8.76% vs 4.81%). Frequency of ATR1 C allele (AC+CC genotypes) was found higher hypertensives than controls (39.4% vs 25.9%; P = 0.054). Our results suggest that an interaction exists between the RAS genes and hypertension in Turkish population.

Angiotensinogen and Angiotensin II Type 1 Receptor Gene Polymorphism in Patients with Autosomal Dominant Polycystic Kidney Disease: Effect on Hypertension and ESRD

Autosomal dominant polycystic kidney disease (ADPKD), a common genetic disease, is characterized by the development of hypertension and end stage renal disease. An increase in the activity of the renin-angiotensin system, due to a renal ischemia caused by cyst expansion, contributes to the development of hypertension and renal failure in ADPKD. Recently, the angiotensinogen (AGT) gene, M235T, and angiotensin II type 1 receptor (ATR) gene, A1166C, polymorphisms have been associated with the susceptibility to develop hypertension and renal disease. We hypothesized that the AGT M235T and ATR A1166C polymorphisms could account for some of the variability in the progression of ADPKD. Genotyping was performed in 108 adult patients with ADPKD, and 105 normotensive healthy controls, using PCR and restriction digestion. We analyzed the effects of the AGT M235T and ATR A1166C polymorphisms on hypertension and age at the end stage renal disease (ESRD). Of the 108 patients with ADPKD, 64 (59%) had hypertension and 24 (22%) reached the ESRD. The prevalence of hypertension were; [MM+MT], [TT] genotypes, 60%, 59% (p=1.00) ; [AA], [AC+CC] genotypes, 60%, 50% respectively (p=0.54). The ages at the onset of ESRD were; [MM+MT], [TT] genotypes, 50 +/- 9 years, 56 +/- 8 years (p=0.07) ; [AA], [AC+CC] genotypes, 54 +/- 8 years, 52 +/- 14 years, respectively (p=0.07). There were no differences in the prevalence of hypertension and the ages at the ESRD in relation to the AGT M235T and ATR A1166C polymorphisms. We suggest that the AGT and ATR gene polymorphisms would not have an effect on hypertension or the ESRD in ADPKD.

Renin-Angiotensin-Aldosterone System (RAAS) Gene Polymorphism as a Risk Factor of Coronary In-Stent Restenosis

Intimal proliferation is a main cause of in-stent restenosis. Over-excretion of angiotensin I converting enzyme (ACE) and aldosterone is reported to stimulate intimal hyperplasia and the genetic effect of these molecules may alter the process of in-stent restenosis. We hypothesized that the genetic polymorphisms that alter the expression of genes such as ACE I/D, CYP11B2-344C/T, and AGT M235T can affect in-stent restenosis. We analyzed the angiographic and clinical data of 238 patients (272 stents) who underwent coronary stenting and follow-up angiography, and analyzed the genotypes of ACE I/D, CYP11B2-344T/C, and AGT M235T. There was no significant difference in age, sex, or lipid profiles between the patent and restenosis groups. Diabetes mellitus was more frequent in the binary restenosis group. Quantitative computer-assisted angiographic (QCA) analysis revealed that the risk of in-stent restenosis increased with lesion length and was inversely proportional to post- stenting minimal luminal diameter (MLD) and reference diameter. There was no difference in the frequency of binary restenosis between genotypes in each of the three genes. However, follow-up MLD was significantly smaller in the ACE DD genotype than in the ACE II or ID genotypes. Defining restenosis as MLD 2 mm, the restenosis rate was significantly higher in the ACE DD genotype than in the ACE II or ID genotypes. There was no significant synergistic effect between the three gene polymorphisms. In conclusion, while the ACE I/D polymor phism promoted the progress of in-stent restenosis and was of clinical significance, the other potential variables examined did not correlate with in-stent restenosis.

Polimorfismos del sistema renina-angiotensina aldosterona: implicaciones clínicas y moleculares en las enfermedades cardiovasculares / Polymorphisms of the renin angiotensin aldosterone system: clinical and molecular implications for cardiovascular diseases

Se discute el rol actual de los polimorfismos del sistema renina-angiotensina-aldosterona, específicamente el polimorfismo inserción deleción (I/D) del gen de la enzima convertidora de angiotensina I (ECA), el polimorfismo M235T del gen de angiotensinógeno y el polimorfismo A1166C del receptor tipo 1 de angiotensina II (R-AT1) en relación con algunas enfermedades cardiovasculares de alta prevalencia. También se revisan las evidencias sobre los mecanismos moleculares o celulares subyacentes detrás de una asociación determinada entre un genotipo y un fenotipo. La mejor evidencia actual en favor de alguna relación clínicamente relevante es la que existe entre el polimorfismo ECA I/D con la hipertensión arterial en hombres, lo que además tiene un correlato experimental reciente. Un área adicional de gran relevancia es la relación de estos polimorfismos con diferentes respuestas farmacológicas (o farmacogenómicas), un área de gran actividad e investigación

Frecuencia del genotipo M234T del gen del angiotensinógeno en pacientes venezolanos sobrevivientes de infarto del miocardio / frequency of the genotype M234T of the gene of the angiotensinogen in patients venezuelan survivors of miocardial infartaction

El polimorfismo TT del gen del angiotensinógeno, ha sido asociado con el riesgo de infarto del miocardio y ya que las enfermedades cardiovasculares constituyen la primera causa de muerte en adultos venezolanos mayores de 35 años, nos propusimos evaluarlo en nuestra población. Se estudiaron 175 pacientes sobrevivientes de infarto del miocardio menores de 65 años, apareados, con respecto a los factores de riesgo establecidos para el infarto, con 175 sujetos normales. El DNA genómico fue extraído de leucocitos y los polimorfismos analizados mediante reacción en cadena de la polimerasa. Las características clínicas de ambas poblaciones se compararon mediante la prueba t de Student no apareada. Ambos grupos están en equilibrio de Hardy-Weinberg. Nuestros resultados indican que el genotipo TT del gen del angiotensinógeno es más frecuente en pacientes sobrevivientes de infarto del miocardio que en sujetos normales y conciente de probabilidades indica el riesgo de infarto del miocardio en 2,088 veces mayor para el genotipo TT, que para el genotipo CC (1,249