Relation between the angiotensin-converting enzyme insertion/deletion polymorphism and blood pressure in Japanese male subjects

Angiotensin-converting enzyme gene insertion/deletion polymorphism and hypertension disease

Background: The renin-angiotensin system (RAS), which is important for controlling haemostasis in the body, can increase the development of essential hypertension (HTN). Various surveys have shown that ACE I/D polymorphism that influences ACE activity, a key component of RAS, has been known to be associated with the risk of HTN. The goal of this study was to investigate the correlation between ACE (I/D) polymorphism and HTN.Methods: Blood samples were obtained from 102 patients and 104 healthy individuals. The two groups were matched by age and sex. Informed consent was prepared for the study. The demographic data were collected using a questionnaire. White blood cells (WBCs) and then DNA were extracted from whole blood. After this, the PCR test was performed using specific primers. PCR products were examined using 1% agarose gel. Individuals with genotype II having a band of 490 bp, ID two band of 490 bp and 190 bp, and individuals with DD genotype, have a band in region 190 bp.Results: The average age of the patients was 52.7 ± 7.5 years. A significant difference was seen in the distribution of DD, II and I/D genotypes of ACE polymorphism between the essential hypertensive patients (44.1, 10.8, and 45.1%) and their ethnically matched healthy control (61.5, 3.8, and 24.6%, respectively). Our study showed an increased risk of disease in people with II genotype in comparison to ID and DD genotypes (0.46 (0.1-1.75) and 0.26 (0.05-0.94), respectively).Conclusions: The present study demonstrated that ACEI/D polymorphism is characterised with greater risk of essential HTN in the Lorestan province. II genotype increased the relative risk of essential HTN in the population. In the future, more investigations with more samples size are recommended for the better study of genetic factors in hypertensive patients.

Genetic polymorphisms associated with reactive oxygen species and blood pressure regulation

Hypertension is the most prevalent cause of cardiovascular disease and kidney failure, but only about 50% of patients achieve adequate blood pressure control, in part, due to inter-individual genetic variations in the response to antihypertensive medication. Significant strides have been made toward the understanding of the role of reactive oxygen species (ROS) in the regulation of the cardiovascular system. However, the role of ROS in human hypertension is still unclear. Polymorphisms of some genes involved in the regulation of ROS production are associated with hypertension, suggesting their potential influence on blood pressure control and response to antihypertensive medication. This review provides an update on the genes associated with the regulation of ROS production in hypertension and discusses the controversies on the use of antioxidants in the treatment of hypertension, including the antioxidant effects of antihypertensive drugs.

Translating Genomic Advances to Physical Therapist Practice: A Closer Look at the Nature and Nurture of Common Diseases

The Human Genome Project and the International HapMap Project have yielded new understanding of the influence of the human genome on health and disease, advancing health care in significant ways. In personalized medicine, genetic factors are used to identify disease risk and tailor preventive and therapeutic regimens. Insight into the genetic bases of cellular processes is revealing the causes of disease and effects of exercise. Many diseases known to have a major lifestyle contribution are highly influenced by common genetic variants. Genetic variants are associated with increased risk for common diseases such as cardiovascular disease and osteoarthritis. Exercise response also is influenced by genetic factors. Knowledge of genetic factors can help clinicians better understand interindividual differences in disease presentation, pain experience, and exercise response. Family health history is an important genetic tool and encourages clinicians to consider the wider client-family unit. Clinicians in this new era need to be prepared to guide patients and their families on a variety of genomics-related concerns, including genetic testing and other ethical, legal, or social issues. Thus, it is essential that clinicians reconsider the role of genetics in the preservation of wellness and risk for disease to identify ways to best optimize fitness, health, or recovery. Clinicians with knowledge of the influence of genetic variants on health and disease will be uniquely positioned to institute individualized lifestyle interventions, thereby fulfilling roles in prevention and wellness. This article describes how discoveries in genomics are rapidly evolving the understanding of health and disease by highlighting 2 conditions: cardiovascular disease and osteoarthritis. Genetic factors related to exercise effects also are considered.

Angiotensin-converting enzyme insertion/deletion polymorphism, 24-h blood pressure profile and left ventricular hypertrophy in hypertensive individuals: a cross-sectional study

Background

The absence of nocturnal blood pressure dipping (ND) identified by 24-h ambulatory blood pressure monitoring (ABPM) correlates with a worse cardiovascular prognosis. The renin–angiotensin system influences blood pressure levels and the occurrence of target organ damage (TOD). Thus, the aim of this study was to correlate the angiotensin-converting enzyme gene (ACE) insertion/deletion (I/D) polymorphism with the 24-h blood pressure profile and TOD in hypertensive individuals.

Methods

155 non-diabetic hypertensive individuals on antihypertensive treatment underwent ABPM. Peripheral blood samples were drawn for biochemistry and genetic analysis of the ACE I/D polymorphism by polymerase chain reaction. ND was defined as ≥10 % differences in the mean systolic blood pressure (BP) during wakefulness and sleep.

Results

There were no differences in clinical or biochemical variables or TOD in respect to ND status, except for higher BP levels during sleep (p < 0.001) in non-dippers. There was significant difference in the prevalence of left ventricular hypertrophy (LVH) between ACE genotypes (II: 13.0 %; ID: 34.1 %; DD: 46.5 %; p value = 0.024) with an increased risk in carriers of the DD genotype (OR = 5.80; IC 95 % 1.50–22.44; p value = 0.011). Carriers of the D allele had higher systolic BP during wakefulness and by ABPM (p < 0.05), higher left ventricular mass (117.3 ± 50.0 vs. 100.3 ± 25.7; p value = 0.017) and higher prevalence of LVH (37.4 vs. 12.5 %; OR = 4.14; 95 % IC: 1.17–14.65; p value = 0.028), compared to the II genotype.

Conclusions

The DD genotype is associated with a higher prevalence of LVH. The presence of the D allele appears to be associated with higher mean 24-h and wake systolic BP measured by ABPM in hypertensive patients under antihypertensive treatment.

High Incidence of ACE/PAI-1 in Association to a Spectrum of Other Polymorphic Cardiovascular Genes Involving PBMCs Proinflammatory Cytokines in Hypertensive Hypercholesterolemic Patients: Reversibility with a Combination of ACE Inhibitor and Statin

Cardiovascular diseases (CVDs) are significantly high in the Lebanese population with the two most predominant forms being atherosclerosis and venous thrombosis. The purpose of our study was to assess the association of a spectrum of CVD related genes and combined state of hypertension hypercholesterolemia (HH) in unrelated Lebanese. Twelve polymorphisms were studied by multiplex PCR and reverse hybridization of DNA from 171 healthy individuals and 144 HH subjects. Two genes were significantly associated with HH: ACE (OR: 9.20, P<0.0001) and PAI-1 (OR: 2.29, P = 0.007), respectively with the occurrence of the risky alleles “Del” and “4G”. The frequencies of the Del and 4G alleles were found to be 0.98 and 0.90 in the HH group versus 0.84 and 0.79 in the healthy group, respectively. Serum ACE activity and PAI-I increased significantly with Del/Del and 4G/5G genotypes. The co-expression of Del/4G(+/+) was detected in 113 out of 171 (66.0%) controls and 125 out of 144 (86.8%) HH subjects. Del/4G(-/-) was detected in only 6 (3.5%) controls and undetected in the HH group. Three venous thrombosis related genes [FV(Leiden), MTHFR(A1298C) and FXIII(V34L)] were significantly related to the prominence of the co-expression of Del/4G(+/+). A range of 2 to 8 combined polymorphisms co-expressed per subject where 5 mutations were the most detected. In Del/4G(+/+) subjects, peripheral blood mononuclear cells (PBMCs) produced significant elevated levels of IFN-γ and TNF-α contrary to IL-10, and no variations occurred for IL-4. ACE inhibitor (ramipril) in combination with statin (atorvastatin) and not alone reversed significantly the situation. This first report from Lebanon sheds light on an additional genetic predisposition of a complex spectrum of genes involved in CVD and suggests that the most requested gene FVL by physicians may not be sufficient to diagnose eventual future problems that can occur in the cardiovascular system. Subjects expressing the double mutations (Del/4G) are at high risk for the onset of CVDs.

The ACE I/D polymorphism is associated with nitric oxide metabolite and blood pressure levels in healthy Mexican men

The I/D insertion/deletion polymorphism of the angiotensin-converting enzyme has been related to hypertension. This polymorphism also seems to have gender related implications. Angiotensin II contributes to the production and release of oxygen reactive species that react with nitric oxide, inactivating its effects.

OBJECTIVE

To establish whether the ACE I/D polymorphism correlates with nitric oxide plasma metabolites in healthy men and women.

METHODS

Among 896 subjects between 18 and 30 years of age range, 138 fulfilled inclusion criteria. The polymorphism was identified by polymerase chain reaction, and blood nitric oxide metabolites were analyzed following the method described by Bryan.

RESULTS

Both systolic and diastolic arterial pressures were higher in men than in women (107/67 vs. 101/65 mm Hg, p<0.001). In terms of the ACE gene, there were differences in the concentration of nitric oxide metabolites in men with the I/D and D/D genotypes when compared to carriers of the I/I genotype (33.55 and 29.23 vs. 53.74 pmol/ml; p=<0.05), while there were no significant differences in women when compared by genotype. Men with the D/D genotype had higher systolic blood pressure than I/D carriers (111 vs. 104 mm Hg, p<0.05). We observed no arterial blood pressure differences in women when grouped by ACE genotype.

CONCLUSIONS

The ACE D/D genotype was associated with nitric oxide metabolite levels and systolic blood pressure in clinically healthy men while it had no effect in women.

The association of hypertension with renin-angiotensin system gene polymorphisms in the Lebanese population

AIM

The study objective was to examine the association of hypertension in the Lebanese population with three renin-angiotensin system gene polymorphisms (RAS): angiotensin-converting enzyme (ACE), angiotensinogen (AGT) and angiotensin-receptor type 1 (AT1R).

METHODS

A total of 270 subjects (124 hypertensive vs 146 normotensive) were genotyped for ACE insertion (I)/deletion (D), AGT (M235T), and AT(1)R (A1166C) gene polymorphisms by polymerase chain reaction and restriction fragment length polymorphism.

RESULTS

The studied genes showed no deviation from Hardy-Weinberg equilibrium. No association could be reported with the ACE I/D polymorphism, although the D allele frequency was high (77%) in patients. AGT TT genotype prevalence was found to be lower in hypertensive versus normotensive subjects (p<0.0001). AT(1)R CC and AC genotypes were significantly more frequent in hypertensive than normotensive subjects (p<0.0001).

CONCLUSION

The first conducted study on the RAS gene polymorphisms in Lebanese hypertensive patients demonstrated a possible association of the AGT T and AT(1)R C alleles with hypertension.

Is there a gender difference between ACE gene and race distance?

We aimed to examine the association between the angiotensin I-converting enzyme (ACE) gene (insertion (I) and deletion (D)) polymorphism in Japanese university track athletes and race distance, as well as to evaluate the gender effects on this association. The ACE I/D allele frequency was determined in 277 athletes (176 men, 101 women; aged 19.7 +/- 1.2 years), who were then grouped on the basis of their major competitive race distances (short distance (SD), < or = 200 m; middle distance (MD), 400-800 m, and long distance (LD), > or =1500 m). The ACE I allele frequency increased with the distance (44.4%, 48.4%, and 66.2% for the SD (n = 107), MD (n = 62), and LD (n = 108) groups, respectively; p < 0.001, chi(2) test). On multinomial logistic regression analysis, significant associations between ACE genotype and race distance were observed only in male athletes (ID vs. SD, p = 0.004; ID vs. LD, p = 0.030; II vs. LD, p = 0.001). There was no significant association between ACE genotype and race distance in female athletes. We conclude that the ACE I allele is overrepresented in endurance athletes, and that its frequency varies depending on gender.

Insertion/deletion polymorphism of angiotensin converting enzyme gene in Korean hypertensive adolescents

The essential role of the renin-angiotensin system (RAS) in controlling blood pressure has been well established. Genes encoding components of the RAS have been proposed as candidate genes that determine genetic predisposition to hypertension and the risk of developing cardiovascular complications. The purpose of this study was to analyze angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphisms in Korean hypertensive adolescents, and to determine the association between ACE genotype and cardiovascular risk. Forty hypertensive adolescents (16-17 years old, systolic blood pressure (BP) > or =140 mm Hg and/or diastolic BP > or =90 mm Hg) and a control group of twenty normotensive adolescents were included in the study. Obesity index (OI) and body mass index (BMI) were calculated. Skin fold thickness and arm circumference were also measured. Fat mass and fat distribution were analyzed by bioelectrical impedance. Blood pressure was measured at resting state by oscillometric methods. Serum aldosterone, renin, insulin, ACE, homocysteine, vitamin B12, and folate levels were evaluated after a fasting period of 12 h. The carotid intima-media thickness (IMT) and carotid artery diameter were measured by carotid ultrasound. Pulse wave velocity (PWV) and ankle-brachial index (ABI) were also measured. Polymerase chain reaction (PCR) was conducted to amplify DNA from blood samples of each individuals to analyze ACE I/D polymorphism. Genotype frequencies of I/I were 37.5%, I/D 45.0% and D/D 17.5%. Serum ACE levels were 33.5 +/- 8.7 U/l in I/I genotype, 48.6 +/- 19.8 U/l in I/D genotype and 61.4 +/- 22.7 U/l in D/D genotype, which showed that ACE levels were significantly higher in those with D/D or I/D genotype than in I/I genotype. Carotid IMT was significantly greater in D/D group than in I/I group. In conclusion, the D allele is associated with the increased level of ACE in Korean hypertensive adolescents.

Angiotensin-converting enzyme polymorphisms and risk of spontaneous deep intracranial hemorrhage in Taiwan

BACKGROUND AND PURPOSE

This study examines whether angiotensin-converting enzyme (ACE) gene polymorphisms are associated with the risk of spontaneous deep intracerebral hemorrhage (SDICH) in Taiwan using a case-control study.

METHODS

Totally, 217 SDICH patients and 283 controls were recruited. Associations of ACE A-240T and ACE I/D polymorphisms with SDICH were examined under the additive model and adjusted for gender, age, body mass index, total cholesterol level, smoking history, alcohol use, hypertension, and use of ACE inhibitors.

RESULTS

Hypertension, diabetes mellitus, family history of spontaneous intracerebral hemorrhage (SICH), and low cholesterol level increase risk of female SDICH, whereas hypertension, alcohol use, smoking history, family history of SICH, and low cholesterol level are an important risk factor for male SDICH. After adjusting for covariates, only haplotype ACE T-D (OR = 2.7, 95% CI, 1.1-6.5, P = 0.02) was associated with female SDICH.

CONCLUSIONS

This study demonstrates that environmental risk factors play a major role and ACE polymorphisms play a minor role in contributing risk of SDICH in Taiwan.

Five polymorphisms in gene candidates for cardiovascular disease in Afro-Brazilian individuals

Associations of polymorphisms in the angiotensin I-converting enzyme (ACE), apolipoprotein B (APOB) and apolipoprotein E (APOE) genes with hypertension and variations in lipid serum levels were evaluated in 184 Afro-Brazilians with a familial history of coronary artery disease (CAD). ACE (Ins/Del) and APOB (Ins/Del, XbaI, and EcoRI) and APOE (HhaI) polymorphisms were determined by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analyses on agarose, and polyacrylamide gel electrophoresis. Serum lipids were measured by means of routine enzymatic assays. The results showed a high frequency of hypertension (44%) in Afro-Brazilians that was increased in subjects >40 years old and those with a blood mass index (BMI) higher than 25 kg/m(2) (P<0.001). The ACE Del allele was associated with hypertension in men >40 years old (P<0.05). APOE (HhaI) and APOB (XbaI and Ins/Del) polymorphisms were not associated with hypertension or variations in serum concentrations of lipids, while subjects with the APOB E- allele had higher low-density lipoprotein cholesterol (LDL-C) levels than E+ carriers (P<0.05). These results suggest that ACE Ins/Del polymorphism is associated with hypertension, and APOB EcoRI polymorphism is associated with LDL-C variation in Afro-Brazilians.

Angiotensin-converting enzyme, sleep-disordered breathing, and hypertension

The angiotensin-converting enzyme (ACE) gene insertion/deletion polymorphism influences ACE activity, cardiovascular risk, blood pressure, and possibly the risk of developing Alzheimer's dementia. We explored the association of the insertion/deletion polymorphism with sleep-disordered breathing (SDB) and hypertension in 1,100 subjects of the Wisconsin Sleep Cohort. The polymorphism did not influence body mass index or the occurrence of SDB, but was dose-dependently associated with blood pressure. Interestingly, SDB and the insertion/deletion polymorphism interacted significantly to modulate blood pressure independently of age, sex, ethnicity, and body mass index. Most specifically, the association of the deletion allele with hypertension was most pronounced in subjects with mild to moderate degrees of sleep apnea (5 < or = apnea-hypopnea index < or = 30). We hypothesize that in the absence of SDB the effect of the deletion allele alone may not be sufficient to increase blood pressure. At severe levels of SDB, the effect of sleep apnea on blood pressure overwhelms any association of the deletion allele with hypertension and occurs independent of any ACE gene genotype.