Israel Medical Association Journal

Background: Anti-endothelial cell antibodies (AECA) are a known biomarker of endothelial dysfunction and damage in clinical practice, especially in autoimmune disease.

Objectives: To determine the relation between natural AECA levels and prognosis related to coronary artery disease.

Methods: Candidates for coronary angiography were prospectively enrolled. AECA levels were determined by ELISA assay. Mortality was evaluated after more than 5 years follow-up.

Results: Of a total 857 patients, 445 had high AECA levels (group 1) and 412 had low levels (< 1 OD unit, group 2). Both groups did not differ in age, sex, or presence of diabetes. The median follow up was 2293 days (76 months). Patients with high AECA levels were more likely to have normal coronary arteries on angiography (21.6% vs. 16.9%, P = 0.047) and less likely to have calcified lesions (19.0% vs. 26.6%, P = 0.028) and lower prevalence of abnormal renal functions (71.1 mg/dl vs. 66.5 mg/dl, P = 0.033). Patients with higher AECA levels had lower mortality levels (20.1% vs. 27.6%, P = 0.006). A logistic regression model demonstrated independent association between lower AECA levels and the presence of coronary atherosclerosis based on angiogram.

Conclusions: After a median of more than 6 years, higher natural AECA levels were associated with less coronary artery disease and lower mortality rates in patients undergoing coronary angiography

Microvascular damage, clinically expressed by Raynaud’s phenomenon, is generally the first symptom of the disease and the injured vascular cells, both endothelial and perivascular, may transdifferentiate to myofibroblasts, thus leading to collagen deposition in the tissue and consequent fibrosis. Systemic sclerosis (SSc, scleroderma) is complex disease characterized by autoimmunity, vasculopathy, and fibrosis. It has been shown that microvascular damage may be the first symptom of SSc. Injured endothelial cells and pericytes may transdifferentiate into myofibroblasts, the cells responsible for fibrosis and collagen deposition in the tissue. Based on these factors, the process of myofibroblast generation may link two pivotal events of SSc: microvascular damage and fibrosis. Understanding the development, differentiation, and function of myofibroblasts is therefore crucial to individuate early pathogenetic events and develop new therapeutic target for SSc, a condition in which no disease-modifying agents are available. The aim of this review was to discuss the possible origins of myofibroblasts in SSc, highlighting the process of endothelial mesenchymal transition and pericytes to myofibroblast transition and to show how these events may contribute to pathogenesis of the disease.

Abstract

Background: Hyperhomocysteinemia is associated with increased cardiovascular risk, but treatment with folic acid has no effect on outcome in unselected patient populations.

Objectives: To confirm previous observations on the association of homozygosity for the TT MTHFR genotype with B12 deficiency and endothelial dysfunction, and to investigate whether patients with B12 deficiency should be tested for 677MTHFR genotype.

Methods: We enrolled 100 individuals with B12 deficiency, tested them for the MTHFR C677T polymorphism and measured their homocysteine levels. Forearm endothelial function was checked in 23 B12-deficient individuals (13 with TT MTHFR genotype and 10 with CT or CC genotypes). Flow-mediated dilatation (FMD) was tested after short-term treatment with B12 and folic acid in 12 TT MTHFR homozygotes.

Results: Frequency of the TT MTHFR genotype was 28/100 (28%), compared with 47/313 (15%) in a previously published cohort of individuals with normal B12 levels (P = 0.005). Mean homocysteine level was 21.2 ± 16 mM among TT homozygotes as compared to 12.3 ± 5.6 mM in individuals with the CC or CT genotype (P = 0.008). FMD was abnormal (£ 6%) in 9/13 TT individuals with B12 deficiency (69%), and was still abnormal in 7/12 of those tested 6 weeks after B12 and folic treatment (58%).

Conclusions: Among individuals with B12 deficiency, the frequency of the TT MTHFR genotype was particularly high. The TT polymorphism was associated with endothelial dysfunction even after 6 weeks of treatment with B12 and folic acid. Based on our findings we suggest that B12 deficiency should be tested for MTHFR polymorphism to identify potential vascular abnormalities and increased cardiovascular risk. 

Abstract

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by multisystem involvement due to immune dysregulation. Neuropsychiatric systemic lupus erythematosus (NPSLE) includes neurological syndromes involving the central, peripheral and autonomic nervous system, as well as psychiatric syndromes observed in patients with SLE in which other causes have been excluded. The pathogenesis of NPSLE has been attributed to many different mechanisms. In particular, autoantibody-mediated vasculopathy seems to play a major role in the pathogenesis of the clinical features. Several autoantibody specificities have been reported in the serum and cerebrospinal fluid of NPSLE patients. Recently, we demonstrated an association between serum anti-endothelial antibodies (AECA) and psychosis or depression in SLE patients, strengthening the notion of a possible role of this class of autoantibodies in the pathogenesis of the disease. The study of these autoantibodies could be a useful diagnostic and prognostic tool in patients with NPSLE.

Background: The etiology of chest pain with normal epicardial coronary arteries (cardiac syndrome X) seems to be related to endothelial cell dysfunction. Multiple factors are implicated in the pathophysiology, including evelated levels of homocysteine in the blood. Mutations in the MTHFR gene are associated with evelated levels of homocysteine.

Objectives: To test whether abnormal homocysteine metabolism is associated with syndrome X.

Methods: Forty-two women with chest pain, positive stress test and normal coronary arteries (syndrome X) and 100 asymptomatic women (controls) were studied for the C677T mutation. Vitamin B12, folic acid, and plasma levels of homocysteine were also measured. Endothelial cell function was studied in 10 patients with syndrome X and homozygosity for C677T mutation, and in 10 matched healthy controls. Folic acid (5 mg daily) was prescribed to syndrome X patients after initial measurements of ECF[1]. Following 13 weeks of treatment, ECF and blood tests were repeated and compared to baseline measurements.

Results: Homozygosity for C677T mutation was doubled in syndrome X vs. control (33%, 14/42 vs. 16%, 16/100, P < 0.02), and homocysteine levels were increased (9.16 ± 2.4 vs. 8.06 ± 2.6 μmol/L, P = 0.02). In the 10 homozygous patients, homocysteine levels decreased significantly after treatment with 5 mg/day folic acid (10 ± 3.3 vs. 5.4 ± 1.1 µmol/L, P = 0.004). Abnormal baseline ECF improved after treatment with folic acid: flow-mediated dilatation was greater (11.3 ± 7.9% vs. 0.7 ± 4.5%, P < 0.002), as was nitroglycerin-mediated dilatation (15.2 ± 9.0% vs. 5.6 ± 6.4%, P < 0.003). Frequency of chest pain episodes was significantly reduced after 13 weeks of folic acid treatment.

Conclusion: Our findings establish the association between the C677T mutation, endothelial cell dysfunction and cardiac syndrome X, and provide a novel and simple therapy for a subset of patients with syndrome X and homozygosity for the C677T mutation.