Association of the -344T/C aldosterone synthase gene variant with essential hypertension.

The aldosterone synthase gene (CYP11B2) is an important candidate gene region in essential hypertension. We therefore studied the association of -344T/C polymorphism of the CYP11B2 gene with the presence and severity of hypertension in a case-control study. We studied 369 individuals, of whom 213 were hypertensive patients (139 controlled hypertensive, 74 resistant hypertensive) and 156 were healthy normotensive subjects. The -344T/C polymorphism of the CYP11B2 gene was determined using polymerase chain reaction - restriction fragment length polymorphism analysis. The distribution of genotypes in normotensive controls and hypertensive subjects were: TT 25.6 vs. 31.9 %, TC 51.9 vs. 57.3 % and CC 22.4 vs. 10.8 %. The -344T/C variant was associated with hypertension. Subjects carrying the -344T allele had a greater risk of hypertension compared to those having C allele (chi(2)=5.89, p<0.05). The frequency of CC genotype was significantly lower in hypertensive patients than in normotensive controls (chi(2)=9.44, p<0.01). A stepwise logistic regression analysis confirmed these findings. We did not find an association of -344T/C variant with the resistance of hypertensive patients to combination therapy, but we observed an association of -344T/C polymorphism of aldosterone synthase gene with increased risk of hypertension. These results support a potential role of -344T/C CYP11B2 gene polymorphism in genetic predisposition to develop hypertension.

[Is mild essential hypertension without obvious organ complications and risk factors associated with increased levels of circulating markers of endothelial dysfunction? Effect of ACE inhibitor therapy]. / Je mírná esenciální hypertenze bez zrejmých orgánových komplikací a rizikových faktoru provázena zvýsenými hladinami cirkulujících markeru endoteliální dysfunkce? Vliv lécby ACE-inhibitory.

The objective of the investigation was to assess whether circulating adhesion molecules, von Willebrand factor (vWf) and endothelin-1 are elevated in patients with mild uncomplicated essential hypertension without further risk factors of atherosclerosis and whether they could serve as indicators of endothelial dysfunction in this form of hypertension. Furthermore the authors investigated the effect of ACE inhibitor treatment (ACEI), quinapril, on the level of these markers of endothelial dysfunction. The level of adhesion molecules [intercellular cytoadhesion molecule-1 (ICAM-1), E-selectin, P-selectin], von Willebrand s factor (vWf) and endothelin-1 were assessed in patients with mild essential hypertension without further cardiovascular risk factors or clinical manifestations of atherosclerosis before and after quinapril treatment (n = 25) and compared with normotensive controls (n = 29). The results of the examinations provided evidence that contrary to controls the hypertensive subjects had significantly higher ICAM-1 levels (237.8 vs. 207.8 ng/ml, P = 0.02) vWf (118 vs. 106 IU/dl, p < 0.05) and endothelin-1 (5.81 vs. 5.15 fmol/ml, p < 0.05). Three-month treatment of hypertensive patients with ACEI led to a significant drop of endothelin-1 levels (5.81 vs. 5.26 fmol/ml, p = 0.01). The authors proved also an unequivocal declining trend of other cytoadhesion molecules and vWf after ACEI treatment, the changes however were not statistically significant. From the investigation it may be concluded that also patients with uncomplicated essential hypertension without other cardiovascular risk factors or clinical manifestations of atherosclerosis have significantly elevated plasma levels of ICAM-1, vWf and endothelin-1. Higher concentrations of these factors suggest endothelial dysfunction already in mild forms of essential hypertension without further risk factors or cardiovascular complications. A significant drop of endothelin-1 and declining trend of the other investigated indicators suggest that ACEI treatment can favourably influence endothelial dysfunction in hypertensive patients also independently on reduction of the BP.

Association analysis of Arg16Gly polymorphism of the beta2-adrenergic receptor gene in offspring from hypertensive and normotensive families.

OBJECTIVE: Since beta2-adrenergic receptors (beta2AR) can influence blood pressure not only by vasodilation, but also participate in noradrenaline release from sympathetic nerve endings, we have studied whether Arg16Gly polymorphism of the beta2AR gene is associated with predisposition to essential hypertension and increased plasma noradrenaline concentration in offspring from normotensive (SN) and hypertensive parents (SH). DESIGN AND METHODS: The study population consisted of 105 young SN and 101 SH subjects matched for age and body mass index. Arg16Gly polymorphism of the beta2AR gene was determined by polymerase chain reaction (PCR) technique and subsequent incubation with NcoI restriction enzyme. Resulting fragments were separated using electrophoresis on a 4.2% Metaphor agarose gel. RESULTS: SH already had significantly higher systolic BP, and a tendency to higher diastolic BP than the SN group. The frequency of Arg/Arg homozygotes was significantly increased in SH when compared to SN (25% vs 15%). Results of logistic regression analysis showed the highest relative risk for the Arg/Arg genotype and suggested a recessive action of the Arg16 variant. There was an increased diastolic BP in Arg/Arg homozygotes of the SN group (p = 0.029). This genotype also had a tendency to increased heart rate in both groups (p = 0.049). There was no relationship of this polymorphism with plasma noradrenaline concentration. CONCLUSION: Our findings suggest that genetic variability of the beta2AR gene is implicated in predisposition to essential hypertension. However, the contradictory results between individual studies indicate that the action of the beta2AR gene is indirect, through multiple intermediate phenotypes and gene interactions.

Cardiac involvement in Wilson disease.

BACKGROUND: Wilson disease is an inherited autosomal recessive disorder of copper metabolism resulting in pathological accumulation of copper in the liver, brain and other tissues. One of the reported manifestations is cardiac involvement. METHODS: We studied 42 patients with Wilson disease (19 men and 23 women, mean age 34 +/- 10 y) and 42 age- and sex-matched healthy volunteers. All subjects underwent complete echocardiographic examination; 24 h ECG Holter monitoring was performed in 23 Wilson disease patients. RESULTS: In comparison to healthy subjects, patients with Wilson disease had increased thickness of the interventricular septum (9.5 +/- 1.4 vs 8.6+/-1.1 mm, p < 0.01) and left ventriclular (LV) posterior wall (9.1 +/- 1.3 vs 8.2 +/- 1.0 mm, p < 0.01). While the two groups did not differ in LV mass index, relative LV wall thickness was significantly increased in Wilson disease patients compared to control subjects (0.39 +/- 0.06 vs 0.34 +/- 0.04 p < 0.001). Concentric LV remodelling was present in 9 patients (21%) and LV hypertrophy in one patient. Systolic LV function showed a nonsignificant trend towards lower values in Wilson disease patients (EF 62 +/- 5% vs 64 +/- 50%, p = 0.06). Diastolic filling and the frequency of valvular abnormalities were comparable in both groups. The established echocardiographic abnormalities did not correlate with the type of Wilson disease manifestation, the presence of the His1069Gln mutation, laboratory parameters or the duration and type of therapy. Twenty-four-hour ECG Holter monitoring detected ECG abnormalities in 10 patients (42%), the most frequent findings being runs of supraventricular tachycardias and frequent supraventricular ectopic beats. CONCLUSIONS: Cardiac involvement in Wilson disease patients was mild, characterized by LV parietal thickening with an increased prevalence of concentric LV remodelling and a relatively high frequency of benign supraventricular tachycardias and extrasystolic beats.

Circulating intercellular cell adhesion molecule-1, endothelin-1 and von Willebrand factor-markers of endothelial dysfunction in uncomplicated essential hypertension: the effect of treatment with ACE inhibitors.

The aim of the study was to examine whether the circulating cell adhesion molecules, von Willebrand factor (vWf) and endothelin-1, are elevated in patients with essential hypertension with no other risk factors for atherosclerosis and thus may serve as a markers of endothelial dysfunction in uncomplicated hypertension. Furthermore, the effect of treatment with the ACE inhibitor, quinapril, on levels of endothelial dysfunction markers were studied. The levels of adhesion molecules (intercellular cell adhesion molecule-1 [ICAM-1], E-selectin, P-selectin), von Willebrand factor (vWf) and endothelin-1 were measured in patients with hypertension without any other risk factors of atherosclerosis before and after treatment with quinapril (n = 22) and in normotensive controls (n = 22). Compared with normotensive subjects, the hypertensive patients had significantly higher levels of ICAM-1 (238 vs 208 ng/ml, P = 0.02), vWf (119 vs 105 IU/dl, P < 0.05) and endothelin-1 (5.76 vs 5.14 fmol/ml, P < 0.05). Three-month treatment of hypertensive patients with quinapril led to a significant decrease in the levels of endothelin-1 (5.76 vs 5.28 fmol/ml, P < 0.01). We did not observe significant changes in the levels of adhesion molecules and vWf after ACE inhibitor treatment, although a trend toward a decrease was apparent with all these parameters. Patients with uncomplicated hypertension with no other risk factors of atherosclerosis had significantly elevated levels of ICAM-1, vWf, and endothelin-1. Our data suggest that these factors may serve as markers of endothelial damage even in uncomplicated hypertension. In hypertensive patients, treatment with the ACE inhibitor quinapril resulted in a significant decrease in endothelin-1 levels. These findings indicate a beneficial effect of ACE inhibitors on endothelial dysfunction in hypertensive patients.