Israel Medical Association Journal

Background: Patients with type 2 diabetes mellitus (T2DM) have a high rate of cardiovascular disease (CVD). The Mediterranean diet is preferred for CVD prevention. Endothelial dysfunction is demonstrated early in T2DM.

Objectives: To study the effects of dietary intervention of T2DM patients without known CVD on endothelial function and vascular inflammation.

Methods: A prospective study enrolled 22 patients with T2DM. Patients were divided randomly into two groups: an intervention group with 12 patients (55 ± 7 years old, 6 women) and a control group with 10 patients (59 ± 10 years old, 5 women). Clinical evaluation included body mass index (BMI) and endothelial function measured by the flow mediated percent change (FMD%). Fasting blood was drawn on entry to the study and 3 months later, measuring C-reactive protein (CRP), intercellular adhesion molecule-1 (ICAM-1), total cholesterol, triglycerides, and glycosylated hemoglobin (HbA1C%). The intervention was based on weekly telephone calls by a clinical dietitian for 3 months.

Results: In the intervention group CRP and ICAM-1 were reduced (from 4.2 ± 3.3 mg/dl to 0.4 ± 0.5 mg/dl, P = 0.01 and from 258.6 ± 98.3 ng/ml to 171.6 ± 47.7 ng/ml, P = 0.004). Endothelial function (FMD%) was improved (from 0.5 ± 8.0% to 9.5 ± 11.5%, P = 0.014). No change was observed in BMI, HbA1C%, total cholesterol, and triglycerides levels in either group.

Conclusions: Patients with T2DM on the Mediterranean diet who received a weekly telephone call for 3 months improved their endothelial function with reduction of markers of inflammation.

Background: Cardiovascular disease (CVD) is more frequent in patients with systemic lupus erythematosus (SLE) compared with age- and sex-matched healthy subjects. SLE is an autoimmune disease that is more prevalent in women (9:1). Women tend to develop CVD in post-menopausal years; however, women with SLE may develop endothelial dysfunction and CVD at a younger age in the pre-menopausal years.

Objectives: To study the endothelial function of adult-onset SLE patients from the north of Israel (the Galilee region) and to determine whether modern management (including biological treatments) changes the risk of developing CVD.

Methods: Thirteen females with adult-onset SLE without renal involvement were recruited to this prospective study. Clinical parameters (age, height, body mass index [BMI]), laboratory parameters (C-reactive protein [CRP] and hemoglobin level), and vascular responsiveness (flow mediated diameter percent change [FMD%]) were evaluated and compared to 11 age-matched healthy females. Student's t-test was used to find differences between the two groups.

Results: No difference was observed in adult-onset SLE female patients and their age- and sex-matched controls with regard to age (42.1 ± 11.8 years vs. 36.6 ± 10.8 years, P = NS), BMI (25 ± 1.8 kg/m² vs. 25 ± 2.5 kg/m², P = NS), and hemoglobin level (11.9 ± 0.9 gr% vs. 12.7 ± 1.2 gr%, P = NS). However, a significant difference was found in CRP (2.57 ± 2.2 mg vs. 0.60 ± 0.37 mg, P = 0.001), vascular responsiveness (0.94 ± 6.6 FMD% vs. 9.2 ± 8.1 FMD%, P = 0.012), and height (165.7 ± 4.5 cm vs. 171.6 ± 5.8 cm, P = 0.009).

Conclusions: Adult-onset SLE females had impaired endothelial function even though they were treated by modern protocols.

Erectile dysfunction (ED) is a syndrome associated with endothelial dysfunction, which may predict cardiovascular events in men presenting with this syndrome. It has been shown to be associated with a higher rate of acute myocardial infarction and cardiovascular mortality, vascular inflammation, and impaired endothelial function. In this review we present the literature findings and describe the mechanistic pathways that are known to be involved in this syndrome and its related clinical consequences.

Background: Endothelial progenitor cells may have a role in ongoing endothelial repair. Impaired mobilization or depletion of these cells may contribute to progression of vascular disease. Our hypothesis was that endothelial progenitor cells would be suppressed in patients with acute cerebrovascular event based on our previous study that found severe endothelial dysfunction in those patients.

Objectives: To study the ability of patients with acute stroke to build colonies of endothelial progenitor cells.

Methods: We studied the number of colony-forming units of endothelial progenitor cells (CFU-EPCs) from the peripheral blood of 22 male patients with a first-time acute stroke (age 58.09 ± 9.8 years) and 13 healthy men (34 ± 6.7 years), 8 female patients with a first-time acute stroke (54.6 ± 10.3 years) and 6 healthy women (38.3 ± 11.6 years). Endothelium-dependent function was assessed by high-resolution ultrasonography of the brachial artery that measured the change in diameter of the artery by flow-mediated diameter percent change (FMD%). All patients had strokes demonstrated by a brain computed tomography (CT) scan done on admission. Peripheral blood was drawn soon after admission and was processed for endothelial progenitor cells in culture.

Results: Thirty patients without known cardiovascular risk factors and who did not take any medications were admitted with a first-time acute stroke. All demonstrated a strong correlation between CFU-EPCs grown in culture and endothelial dysfunction (r = 0.827, P < 0.01). Endothelial dysfunction with an FMD% of -2.2 ± 9.7% was noted in male patients vs. 17.5 ± 6.8% in healthy males (P = 0.0001), and -7.2 ± 10.1% in female patients vs. 25.1 ± 7.1% in healthy females (P = 0.0001). CFU-EPCs were 5.5 ± 6.3 in men with stroke vs. 23.75 ± 5.3 in healthy males (P = 0.0001), and 7.6 ± 4.9 in women with stroke vs. 22.25 ± 6.7 in healthy females (P = 0.0004).

Conclusions: Patients with acute stroke had an impaired ability to grow CFU-EPCs in culture and exhibited endothelial dysfunction. The novelty of this study was the discovery of the phenomenon of depressed numbers of EPCs and the poor ability to grow colonies of EPCs in the first 24 hours of the cerebrovascular event.

Background: Weight loss surgery is the most effective treatment for obesity, and it reduces cardiovascular and cancer risk through poorly understood mechanisms. MicroRNAs (miRNAs) are short RNA molecules that regulate the stability and translation of many mRNAs. We hypothesized that levels of specific circulating miRNAs are altered following surgery and may contribute to lower cancer risk.

Objectives: To investigate the change of miRNA following surgery.

Methods: All patients underwent gastric “sleeve operation”. RNA was isolated from sera of 21 patients (14 men, 7 women) before and 3 months after surgery. Sera were combined into two pools, which served for cDNA library construction followed by miSeq sequencing. The levels of candidate miRNAs were validated in the individual samples by QRT-PCR.

Results: Serum miR-122 was significantly up-regulated 3 months post-bariatric surgery in sera of patients, whose endothelial function had greatly improved. In addition, serum miR-122 levels correlated positively with endothelial function as measured by FMD. The changes in miR-122 levels from pre-surgery to 3 months post-surgery also tended to correlate with the respective changes in FMD.

Conclusions: The serum miR-122/miR-451 ratio may serve as a marker for endothelial function in obese patients. miR-122 is the dominant miRNA in the liver and a known tumor suppressor. Our findings suggest a role for circulating miR-122 in the maintenance of vascular endothelial cells (VECs) and in the prevention of cancer. Further studies are required to elucidate the mechanism of its secretion into circulation and its absorption by VECs, as well as its relevant cellular targets.

Background: Erectile dysfunction (ED), a common problem in males of all ages, can be of organic, psychogenic or combined etiology. Organic ED is mainly caused by vascular and neurological disorders. One of the available tests for differentiating organic from inorganic ED is measuring penile tumescence and rigidity during the REM phase of sleep. However, this test lacks the ability to differentiate between a vascular and non-vascular cause of organic ED. 

Objectives: To compare the results of the EndoPAT test and the nocturnal penile tumescence (NPT) test in patients with erectile dysfunction.

Methods: Twenty patients with ED were recruited for the study. Each participant was evaluated by the SHIM score, RigiScan during polysomnography, and two EndoPAT tests (at the beginning and end of the study).

Results: Seventeen patients had SHIM score ≤ 21; 4 of them had organic ED with a mean EndoPAT score of 1.49, significantly lower than the 1.93 mean EndoPAT score of the 11 patients in the psychogenic ED group (P = 0.047). Two participants had a neurological impairment (spinal trauma and herniated disk). The average SHIM score in the vascular organic group was 6.25 points as compared to 11.69 for the psychogenic group (P = 0.027). The positive predictive value was 43% and the negative predictive value 90%.

Conclusions: EndoPAT could be helpful in excluding organic ED.

 

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. 

Background: Endothelial dysfunction is recognized as a major factor in the development of atherosclerosis and it has a prognostic value.

Objectives: To detect the long-term association of peripheral vascular endothelial function and clinical outcome in healthy subjects and patients with cardiovascular disease.

Methods: We prospectively assessed brachial artery flow-mediated dilation in 110 consecutive subjects (46 CVD[1] patients and 64 healthy controls), mean age 57 ± 11 years; 68 were men. After an overnight fast and discontinuation of all medications for ≥ 12 hours, percent improvement in FMD and nitroglycerin-mediated vasodilatation were assessed using high resolution ultrasound.

Results: %FMD[2] but not %NTG[3] was significantly lower in CVD patients (9.5 ± 8.0% vs. 13.5 ± 8.0%, P = 0.012) compared to healthy controls (13.4 ± 8.0% vs. 16.7 ± 11.0%, P = 0.084; respectively). In addition, an inverse correlation between %FMD and the number of traditional CVD risk factors was found among all study participants (r = -0.23, P = 0.015) and healthy controls (r = -0.23, P = 0.036). In a mean follow-up of 15 ± 2 months, the composite CVD endpoints (all-cause mortality, myocardial infarction, hospitalization for heart failure or angina pectoris, stroke, coronary artery bypass grafting and percutaneous coronary interventions) were significantly more common in subjects with FMD < 6% compared to subjects with FMD > 6% (33.3% vs. 12.1%, P < 0.03, respectively).
Conclusions: Thus, brachial artery %FMD provides important prognostic information in addition to that derived from traditional risk factor assessment

Background: Hypertension is considered resistant if blood pressure cannot be reduced to <140/90 mmHg with an appropriate triple-drug regimen, including an oral diuretic, with all agents administered at maximal dosages. This definition has evolved with the development of new therapies and evidence-based data supporting treatment to lower BP[1] goals.

Objective: To assess whether vitamin C and atorvastatin improve endothelial function and blood pressure control in subjects with resistant arterial hypertension and dyslipidemia.

Methods: Forty-eight hyperlipidemic subjects with RH[2] (office systolic BP >140 mmHg and/or office diastolic BP >90 mm/Hg notwithstanding antihypertensive treatment with three medications in maximal doses) were randomized into three groups to receive additional medication for 8 weeks. Group VTC (n = 17) – mean 24 hour SBP[3] 150.6 ± 5.2 mmHg, DBP[4] 86.1 ± 3.3 mmHg, low density lipoprotein 158.1 ± 24.5 mg/dl) – received vitamin C 500 mg per day; Group ATR (n = 15) – mean 24 hour SBP 153.1 ± 4.8 mmHg, DBP 87.1 ± 6.7 mmHg, LDL[5] 162.6 ± 13.6 mg/dl) – received atorvastatin 20 mg/day; and Group PLA (n = 16) – mean 24 hour SBP 151.1 ± 7.4 mmHg, DBP 84.8 ± 5.9 mmHg, LDL 156.7 ± 26.1 mg/dl – received a placebo. High resolution ultrasound was used to calculate brachial artery flow-mediated dilation, and 24 hour ambulatory BP monitoring was performed at study entry and after 8 weeks.

Results: In the ATR group there were significant reductions of SBP (DSBP1-2: 13.7 ± 5.6 mmHg, P < 0.001), DBP (DDBP1-2: 7.8 ± 5.7 mmHg, P < 0.01), LDL (DLDL1-2: 67.7 ± 28.3 mg/dl, P < 0.001) and improvement of brachial artery FMD[6] (DFMD2-1: 4.2 ± 2.6%). No significant changes in BP, LDL and FMD were observed in the other two groups.

Conclusions: In subjects with RH and dyslipidemia, atorvastatin 20 mg/day compared to vitamin C 500 mg/day may help to achieve better BP control and improve endothelial function in a finite period. A larger trial is needed to assess the drug's efficacy in this population for longer periods.