ACE/DD genotype is associated with hemostasis balance disturbances reflecting hypercoagulability and endothelial dysfunction in patients with untreated hypertension

Interrelationship between COVID-19 and Coagulopathy: Pathophysiological and Clinical Evidence

Since the first description of COVID-19 infection, among clinical manifestations of the disease, including fever, dyspnea, cough, and fatigue, it was observed a high incidence of thromboembolic events potentially evolving towards acute respiratory distress syndrome (ARDS) and COVID-19-associated-coagulopathy (CAC). The hypercoagulation state is based on an interaction between thrombosis and inflammation. The so-called CAC represents a key aspect in the genesis of organ damage from SARS-CoV-2. The prothrombotic status of COVID-19 can be explained by the increase in coagulation levels of D-dimer, lymphocytes, fibrinogen, interleukin 6 (IL-6), and prothrombin time. Several mechanisms have been hypothesized to explain this hypercoagulable process such as inflammatory cytokine storm, platelet activation, endothelial dysfunction, and stasis for a long time. The purpose of this narrative review is to provide an overview of the current knowledge on the pathogenic mechanisms of coagulopathy that may characterize COVID-19 infection and inform on new areas of research. New vascular therapeutic strategies are also reviewed.

Targeted genetic analysis unveils novel associations between ACE I/D and APO T158C polymorphisms with D-dimer levels in severe COVID-19 patients with pulmonary embolism

Only a percentage of COVID-19 patients develop thrombotic complications. We hypothesized that genetic profiles may explain part of the inter-individual differences. Our goal was to evaluate the genotypic distribution of targeted DNA polymorphisms in COVID-19 patients complicated (PE+) or not (PE-) by pulmonary embolism. We designed a retrospective observational study enrolling N = 94 consecutive patients suffering severe COVID-19 with pulmonary embolism (PE+, N = 47) or not (PE-, N = 47) during hospitalization. A panel of N = 13 prothrombotic DNA polymorphisms (FV R506Q and H1299R, FII G20210A, MTHFR C677T and A1298C, CBS 844ins68, PAI-1 4G/5G, GPIIIa HPA-1 a/b, ACE I/D, AGT T9543C, ATR-1 A1166C, FGB - 455G > A, FXIII103G > T) and N = 2 lipid metabolism-related DNA polymorphisms (APOE T 112C and T158C) were investigated using Reverse Dot Blot technique. Then, we investigated possible associations between genotypic subclasses and demographic, clinical, and laboratory parameters including age, obesity, smoking, pro-inflammatory cytokines, drug therapy, and biomarkers of thrombotic risk such as D-dimer (DD). We found that 58.7% of PE+ had homozygous mutant D/D genotype at ACE I/D locus vs. PE- (40.4%) and 87% of PE+ had homozygous mutant C/C genotype at APOE T158C locus vs. PE- (68.1%). In PE+ group, DD levels were significantly higher in D/D and I/D genotypes at ACE I/D locus (P = 0.00066 and P = 0.00023, respectively) and in C/C and T/C genotypes at APOE T158C locus (P = 1.6e-06 and P = 0.0012, respectively) than PE- group. For the first time, we showed significant associations between higher DD levels and ACE I/D and APOE T158C polymorphisms in PE+ vs. PE- patients suggesting potential useful biomarkers of poor clinical outcome.

Insertion/deletion polymorphism of the angiotensin-converting enzyme considerably changes postoperative outcome

STUDY OBJECTIVE

To evaluate the influence of insertion/deletion (ID) polymorphism of the angiotensin-converting enzyme (ACE) gene on clinical outcome of cardiac valve surgery.

DESIGN

Prospective, blinded observational study.

SETTING

Operating room and intensive care unit (ICU) of a university hospital.

PATIENTS

110 adult patients requiring elective cardiac valve surgery requiring cardiopulmonary bypass.

MEASUREMENTS

Patients' preoperative data (age, gender, body weight, New York Heart Association score, medication, biochemical data, and comorbid disorders), anesthetic management (blood pressure, heart rate, blood loss and transfusion, and cardiorespiratory complications and their treatment), and postoperative outcome (life-threatening complications, nosocomial infections, reintubation/reoperation, death, and duration of ICU stay and hospitalization) were recorded. ACE ID was detected by gel electrophoresis following conventional polymerase chain reaction. Patients were divided into two groups postoperatively; groups with II and non-II (ID and DD) genotypes, and group differences were analyzed.

MAIN RESULTS

Distribution of ACE ID in II, ID, and DD genotypes was 29%, 59%, and 12%, respectively. The non-II group had significantly greater postoperative blood loss and transfusion (P < 0.05), more common postoperative infections, and longer ICU stay duration than the II group (P < 0.01).

CONCLUSIONS

ACE ID polymorphism is associated with a higher incidence of postoperative complications, including postoperative infections, in patients undergoing cardiac valve surgery.

Thrombin activatable fibrinolysis inhibitor (TAFI) levels in hypertensive patients and a comparison of the effects of amlodipine and ramipril on TAFI levels

Hypertension is associated with fibrinolysis abnormality. Thrombin-activatable fibrinolysis inhibitor (TAFI) is a novel molecule-linking coagulation and fibrinolysis. The aim of this study was to investigate the levels of TAFI in primary hypertensive patients and to compare the effects of amlodipine and ramipril on TAFI levels. The study was performed with 58 hypertensive subjects and 27 healthy volunteers. Biochemical and hematological parameters and TAFI levels were measured at baseline and after 1-month follow-up. TAFI concentrations increased in hypertensive patients compared with the controls (P = .030). Additionally, TAFI levels decreased with blood pressure control at 1-month follow-up (P = .026). There was no significant difference between TAFI levels in the amlodipine and ramipril groups at baseline. However, after 1-month follow-up, TAFI levels were decreased in the amlodipine group (P = .037) but not in the ramipril group. Our study is the first in the literature to determine increased TAFI levels in primary hypertension patients. In addition, we determined a decrease in TAFI levels in the amlodipine group after 1 month, but none in the ramipril group.

Masked hypertension unfavourably affects haemostasis parameters

OBJECTIVE. Recent evidence demonstrates that masked hypertension (MH) is a significant predictor of cardiovascular disease. The aim of our study was to examine the impact of MH on haemostasis parameters and to compare the findings to those of healthy normotensives matched for age, sex, body mass index and the rest of risk factors. DESIGN AND METHOD. 130 (60 male, 70 female) healthy subjects mean age 45 ± 12 years who had clinic blood pressure < 140/90 mmHg were studied. The whole study population underwent 24-h ambulatory blood pressure monitoring (ABPM). According to the ABPM recordings, 24 individuals (eight males, 16 females) had MH (daytime systolic blood pressure ≥ 135 mmHg or daytime diastolic blood pressure ≥ 85 mmHg - group A) and the remaining 106 subjects (52 males, 54 females) had normal ABPM recordings - group B. Fibrinogen, thrombomodulin ™, the antigens of plasminogen activator inhibitor 1 (PAI-1Ag) and tissue plasminogen activator (tPA-Ag) were determined in the two groups. Results. The PAI-1 Ag, tPA-Ag, fibrinogen and TM levels were significantly higher in the masked hypertensive group than to normotensive control group. CONCLUSIONS. Our findings suggest that subjects with MH have significantly higher fibrinogen, TM, PAI-1Ag and tPA-Ag plasma levels compared with normotensives. This observation may have prognostic significance for future cardiovascular events in subjects with MH and needs further investigation.

Migraine as a systemic vasculopathy

Epidemiological studies suggests that migraine is associated with disorders of the cerebral, coronary, retinal, dermal and peripheral vasculature. There is evidence that migraine is associated with endothelial dysfunction, both as a cause and a consequence. Endothelial dysfunction, a vascular risk factor, is characterized by endothelial activation and impaired vascular reactivity. Plasma and genetic biomarkers for these conditions have been identified. The clinical significance lies in the potential for the rapid identification of migraineurs at increased risk of ischaemic stroke and vascular disease through ascertainment of endothelial dysfunction biomarkers. It is uncertain whether stroke, myocardial infarction and other vasculopathies can be prevented by migraine prophylaxis, endothelial repair, platelet inhibition or a combination of these strategies.

Association of von Willebrand Factor Activity with ACE I/D and MTHFR C677T Polymorphisms in Migrainecha

Angiotensin-converting enzyme (ACE) insertion (I)/deletion (D) and methylene-tetrahydrofolate reductase (MTHFR) C677T polymorphisms are linked to endothelial dysfunction and to cerebral white matter lesions. Objectives of this study were to determine if ACE and MTHFR gene polymorphisms are associated with von Willebrand factor (vWF) activity, an endothelial dysfunction marker, and with a distinct headache phenotype. We enrolled 64 women (18–50 years old) with International Classification of Headache Disorders, 2nd edn migraine without aura (MoA) and 61 with aura (MA). Genotypic frequencies: ACE DD 35%, ID 42%, II 23%, and MTHFR TT 17%, CT 40%, CC 43%. Those with ACE DD genotype had higher levels of vWF activity (152%) compared with ID and II genotypes. Levels were highest (179%) with combined ACE DD and MTHFR TT genotypes. ACE DD was associated with higher headache frequency, and MTHFR TT was associated with MA. In migraine, vWF activity may be a marker of endothelial-mediated genetic risk for ischaemic conditions.

Prevalence of prothrombotic polymorphisms in Greece

The aim of this study was to assess the prevalence of several polymorphisms in genes that are involved in several pathways such as hemostasis, fibrinolysis, platelet membrane receptor activity, endothelial integrity and function, lipid metabolism, and regulation of blood pressure in healthy subjects of Greek origin. Most of these polymorphisms are mainly associated with conditions such as venous thromboembolism and atherothrombosis, and their prevalence has not been studied yet in Greece. We tested 140 healthy individuals for factor V (FV)1691G/A, FV4070G/A, FII 20210G/A, factor XIII (FXIII) exon 2G/T, fibrinogen beta-455G/A, plasminogen activator inhibitor-1 (PAI-1)-675 4G/5G, human platelet antigens 1 (HPA1) a/b, apolipoprotein B (ApoB) 10708 G/A, apolipoprotein E (ApoE) E2, E3, and E4, angiotensin-converting enzyme (ACE) D/I, 5,10 methylenetetrahydrofolate reductase (MTHFR) 677C/T, and MTHFR 1298A/C polymorphisms using a PCR and reverse hybridization technique that detects all of them simultaneously. The allele frequencies observed are in accordance with those reported in other Caucasian populations and almost identical to those of East Mediterranean populations. This first report from Greece may serve as a baseline for planning further investigations of these polymorphisms in association with several clinical entities and for launching guidelines for patient testing of various disease settings in this population.

Migraine and ischaemic heart disease and stroke: potential mechanisms and treatment implications

The migraine-ischemia relationship is best understood in the context of the pathophysiology of migraine. Potential mechanisms of migrainous infarction (stroke occurring during migraine) include vasospasm, hypercoagulability, and vascular changes related to cortical spreading depression. Stroke occurring remote for the migraine attack may be related to arterial dissection, cardioembolism, and endothelial dysfunction. Endothelial dysfunction, a process mediated by oxidative stress, may be a cause or a consequence of migraine, and explain the relationship of migraine to vascular factors and ischemic heart disease. It remains uncertain whether stroke or myocardial infarction can be prevented by migraine prophylaxis, endothelial repair, platelet inhibition, or a combination of these strategies. Although triptans are generally considered safe for use in migraine, caution is warranted in those with multiple vascular risk factors. Known vascular disease is a contraindication to triptan use.

Identification of a novel gene, HCR2, in aorta of hypercoagulable rats using suppression subtractive hybridization

Screening and identification of novel genes involved in hypercoagulable state (HCS) is important in understanding the underlying mechanisms of development of atheroslerosis, which implicated in critical vascular diseases such as coronary heart disease and stroke. HCS was induced in rats with high carbohydrate diet. Subtractive hybridization experiments between aorta tissues from hypercoagulable rats and controls showed that a novel cDNA (GenBank Accession No. AY234417), designated as hypercoagulability related gene-2 (HCR2), was highly expressed in aorta tissue. The predicted protein encoded by HCR2 contains 78 amino acids, which has a theoretical isoelectric point (pI) of 8.59 and molecular weight (MW) of 8841.7 based on sequence analysis. Our data suggest that HCR2 may be involved in HCS and identification of the gene may contribute to our understanding of the mechanisms for the production of a hypercoagulable state of several critical clinical disorders.

Effects of perindopril treatment on hemostatic function in patients with essential hypertension in relation to angiotensin converting enzyme (ACE) and plasminogen activator inhibitor-1 (PAI-1) gene polymorphisms

BACKGROUND AND AIM

An imbalance in the hemostatic system is a frequent finding in untreated essential hypertension (HT), and it has been shown that treatment with angiotensin converting entyme (ACE) inhibitors improves hemostatic function. In order to elucidate the role of genetic factors, we studied hemostasis in patients with untreated and treated HT and correlated the results with ACE I/D and plasminogen activator enhibitor-1 (PAI-1) 4G/5G gene polymorphisms.

METHODS AND RESULTS

Forty-three males with HT (mean age 31.7 +/- 6.8 years) were compared with 34 age and gender-matched controls. All of the patients were treated with perindopril (4 mg/day) and, after one and six months of therapy, their levels of plasma fibrinogen (Fb), t-PA antigen, PAI-1 antigen, von Willebrand factor (vWF), ACE activity and blood pressure were measured. ACE and PAI-1 genotypes were identified by means of the polymerase chain reaction on DNA isolated from peripheral blood lymphocytes. Untreated patients had significantly higher levels of Fb, PAI-1 (p < 0.01) and t-PA (p < 0.05) regardless of their ACE or PAI-1 genotypes. Perindopril reduced blood pressure regardless of ACE or PAI-1 genotype (p < 0.001). ACE II homozygotes showed the greatest decrease in ACE activity (p < 0.01) and a significant reduction in Fb levels (p < 0.05) after just one month of treatment. Analysis of the group as a whole revealed an increase in t-PA antigen levels after six months of treatment, regardless of ACE or PAI-1 genotype (p < 0.01).

CONCLUSIONS

Our results show that essential hypertension predisposes to the procoagulant state characterized by hyperfibrinogenemia and hypofibrinolysis. Perindopril reduced fibrinogen levels in ACE II homozygotes due to its more potent inhibitory action on the renin-angiotensin system in such patients. It improved fibrinolysis by increasing t-PA levels regardless of ACE and PAI-1 genotype.

Angiotensin-converting enzyme gene polymorphism may influence blood loss in a geriatric population undergoing total hip arthroplasty

OBJECTIVES

To evaluate how angiotensin-converting enzyme (ACE) gene polymorphism is associated with perioperative blood loss in hip arthroplasty in a geriatric population.

DESIGN

A case-control study of subjects consecutively undergoing total hip arthroplasty.

SETTING

A department of orthopedic surgery in Italy.

PARTICIPANTS

One hundred five patients, mean age +/- standard deviation 68.6 +/- 10.4, undergoing total hip arthroplasty.

MEASUREMENTS

ACE gene polymorphism was analyzed using polymerase chain reaction. Decrement of hemoglobin (Hb) and hematocrit (Ht) was calculated as the difference between the preoperative and the lowest postoperative value, measured 1, 2, and 3 days after surgery. Total blood loss was calculated as the sum of intra- and postoperative blood loss.

RESULTS

Patients carrying the deletion homozygous and insertion/deletion heterozygous genotypes of the ACE gene show a higher decrement of Hb (P <.01) and Ht (P <.01) and higher total blood loss (P <.007) after hip surgery than subjects carrying the insertion (II) homozygous. The role of ACE gene polymorphism seems hypertension independent. Logistic regression analysis showed that II genotype reduces total blood loss.

CONCLUSIONS

This is the largest study evaluating the distribution of ACE gene genotypes in patients undergoing hip arthroplasty and the first investigating the association between bleeding and ACE gene polymorphism. Our data suggest that II genotype is associated with lower total blood loss.

Clinical significance of plasma D-dimer and von Willebrand factor levels in patients with ulcer colitis

AIM: To investigate the levels of D-dimer (DD) and von Willebrand factor (vWF) and the relationship between DD and vWF in ulcerative colitis (UC) patients.

METHODS: A total of 29 plasma specimens were obtained from patients with ulcerative colitis (male 13, female 16), aged 21-47 years (33 ± 11). Disease activity was assessed by Truelove-Writeria. Patients with a score of above 5 were regarded as having active colitis. Twenty healthy people (male 12, female 8), aged 19-53 years (31 ± 14), served as normal controls. Blood samples were taken from an antecubital vein puncture. Blood (1.8 mL) was injected into the tubes containing sodium citrate (0.13 mmol/L). The plasma was obtained by centrifugation at 3000 r·min^-1 for 10 min, and stored at -80 °C until assayed by ELISA.

RESULTS: The mean plasma levels of DD and vWF in active UC patients were significantly higher than those of the controls (0.69 ± 0.41 vs 0.27 ± 0.11, P < 0.01; 143 ± 46 vs 103 ± 35, P < 0.01). The mean plasma levels of DD in the patients with active disease were higher than those with inactive disease (0.69 ± 0.41 vs 0.48 ± 0.29, P < 0.05). The levels of vWF were not different between active and inactive patients. DD levels were positively related to vWF levels (r = 0.574, P < 0.01). There was no significant difference between levels of DD and vWF and the scope of disease and sex of the patients.

CONCLUSION: vWF is an important feature and a good marker of UC; intravascular thrombus and endothelial cell dysfunction were found in UC patients; and the combined test of DD and vWF is helpful to distinguish the activity of the UC patients.

Relationship of angiotensin converting enzyme genotype with serum triglyceride concentration in stroke patients

The Objective of this research was to study the relationship of angiotensin converting enzyme (ACE) genotype with serum triglycerides concentration in stroke patients. The insertion/deletion (I/D) ACE polymorphism was identified by using polymerase chain reaction in 122 prospectively studied ischemic stroke patients (age 45-91 years). Serum triglycerides concentration was determined at admission and 3 months after the stroke, and compared between the ACE genotype groups (37 D/D, 68 D/I, 17 I/I). All clinical characteristics were similar in the three groups. Patients with D/D genotype had mean serum triglycerides concentration significantly higher in acute (179.0+/-111.8 mg/dl) and chronic phase (176.4+/-121.6 mg/dl) than those with I/I genotype (acute phase: 108.7+/-36.1 mg/dl, P=0.019; chronic phase: 116.0+/-44.3 mg/dl, P=0.021). The results showed that serum triglycerides concentration is elevated in stroke patients with the DD ACE genotype and it may be related to the risk of cerebrovascular disease associated with this polymorphism.

The renin angiotensin system as a risk factor for coronary artery disease

The renin angiotensin system was demonstrated to play a significant role in the genesis of hypertension and regulation of vascular tone over 100 years ago. The early investigations were subsequently expanded to implicate the renin angiotensin system in a variety of physiologic processes that may play a significant role in the initiation and progression of atherosclerosis. The renin angiotensin system modulates vascular structure and left ventricular hypertrophy via a number of trophic effects. Elevated levels of angiotensin II are associated with the generation of oxidative stress, and may thus play a significant role in the earliest phases of atherosclerosis. The role inflammation plays in atherosclerosis is amplified by the renin angiotensin system via the effects on adhesion molecules, growth factors, and chemoattractant molecules, which modulate the migration of inflammatory cells into the subendothelial space. The effects of angiotensin II, which may be at least partially genetically mediated, have been implicated in epidemiologic and clinical studies as a risk factor for the development of atherosclerosis. This review centers on the potential role that the renin angiotensin system plays as a risk factor for the development of atherosclerosis, and the role of converting enzyme inhibition or angiotensin receptor blockade as a mechanism to decrease the initiation, progression, and clinical consequences of the atherosclerotic process.