Relationship between ACE-DD polymorphism and diastolic performance in healthy subjects

Effects of human endothelial gene polymorphisms on cellular responses to hyperglycaemia: role of NOS3 (Glu298Asp) and ACE (I/D) polymorphisms

The functional relevance of NOS3 and ACE genetic variations to endothelial cell function is largely unstudied. Here we tested the functional relevance of the NOS3 (Glu298Asp) polymorphism and ACE (I/D) polymorphism in endothelial cells in vitro. Our hypothesis was that these genetic polymorphisms alter endothelial cell sensitivity to glucose and 3-nitrotyrosine (3NT). Genotyped HUVECs were incubated with glucose, free 3NT or a combination of these two toxicants. Significant differences in glucose-induced cell death and free 3NT-induced cell death were observed among the NOS3 genotypes. Combined glucose/3NT caused increased toxicity among the NOS3 genotypes. No differences were observed among the ACE genotypes in their responses to glucose/3NT. These data demonstrate that the NOS3 genotype may be an important predictor of, or be mechanistically involved in, endothelial vulnerability, whereas the ACE I/D genotype is apparently less important. Thus this NOS3 genetic variation may play a role in vulnerability to endothelium-dependent diabetic vascular complications.

Effects of angiotensin-converting enzyme gene polymorphism and serum vitamin D levels on ambulatory blood pressure measurement and left ventricular mass in Turkish hypertensive population

INTRODUCTION

Regulation of angiotensin converting enzyme (ACE) and angiotensin II (ang-II) levels is under genetic control. 1,25(OH)2 vitamin D3 treatment has been shown to reduce the ang-II level, reduce myocardial hypertrophy and to decrease blood pressure. This study was designed to examine the effect of ACE gene polymorphisms on 24-h ambulatory blood pressure measurement (24 h) values, vitamin D levels and target organ damage in hypertensive patients.

METHODS

This study was carried on 118 patients with essential hypertension (female/male: 70/48, mean age: 49.1+/-7.6 years, hypertension duration: 56+/-40.5 months). All patients were assessed for target organ damage; the eye by retinal examination, the heart with echocardiography and the kidney with blood and 24-h urine analysis. 24-h ambulatory blood pressure measurement was performed in all patients. PCR amplification was employed to detect ACE genotypes.

RESULTS

ACE genotypes were as follows: DD (n=49) 41.5%; ID (n=37) 31.4% and II (n=32) 27.1%. No difference was present between groups of ACE polymorphism when 24-h ambulatory blood pressure measurement values, retinal vascular changes and microalbuminuria were taken into account. Statistically significant left ventricular mass index levels were obtained in the DD group when compared with the non-DD (ID+II) group (P : 0.009). Positive correlations have been noted between left ventricular mass index and day/night and early morning systolic pressures. A negative correlation exists between serum 25 (OH) vitamin D levels and 24-h ambulatory blood pressure measurement values (P<0.05).

CONCLUSIONS

The presence of the D allele is linked with a higher risk for left ventricular mass index in the Turkish hypertensive population.

Effects of canrenoate plus angiotensin-converting enzyme inhibitors versus angiotensin-converting enzyme inhibitors alone on systolic and diastolic function in patients with acute anterior myocardial infarction

BACKGROUND

Aldosterone (ALDO) exerts profibrotic effects, acting via the mineralocorticoid receptors in cardiovascular tissues. Aldosterone antagonism in combination with angiotensin-converting enzyme inhibition may better protect against the untoward effects of ALDO than angiotensin-converting enzyme inhibition alone.

METHODS

In a double-blind randomized study, the tolerability and efficacy of canrenoate (25 mg/d) plus captopril versus captopril alone were evaluated in 510 patients with an acute anterior myocardial infarction (MI), a serum creatinine concentration < 2.0 mg/dL, and a serum potassium level < 5.0 mmol/L. Three hundred forty-one patients received captopril and 25-mg canrenoate (group A). Group B (346 patients) received captopril and placebo. At baseline and at 10, 90, and 180 days after admission, Doppler echocardiography was performed.

RESULTS

Clinical and demographic aspects were similar in both groups. In addition, baseline cardiac enzyme levels, left ventricular function, and incidence of surgical interventions and angioplasty were comparable. Overall, creatinine, blood urea, and serum potassium levels did not show significant differences between groups. However, in 18 patients in group A, increases in serum potassium levels to > 5.5 mEq/L and creatinine levels to > 2.0 mg/L after 10 days of treatment were observed. At 180 days, the mitral E-wave-A-wave ratio was higher (P = .0001) and left ventricular end-systolic volume was smaller (P = .0001) in patients treated with canrenoate than in those receiving placebo. No further side effects were observed during the study period.

CONCLUSIONS

Our data suggest that the combination of captopril plus canrenoate is well tolerated after an acute MI and has beneficial effect on systolic and diastolic parameters and may decrease post-MI remodeling.