C. Agabiti Rosei

[PP.12.08] EFFECTS OF MELATONIN ON THE PRODUCTION OF ADIPONECTIN AND THE EXPRESSION OF ADIPONECTIN RECEPTOR IN THE VISCERAL ADIPOSE TISSUE OF AGING MICE.

Objective: It has been previously demonstrated that inflammation in adipose tissue may be implicated in vascular dysfunction (Circulation 2009; 119(12):1661–1670). A senescence-accelerated prone mouse (SAMP8) is a model of age-related cognitive decline and vascular dysfunction. Several studies demonstrated that SAMP8 suffers from increased oxidative stress and that accelerated senescence was associated with increased oxygen radicals synthesis. We have also recently demostrated that the anticontractile effect of perivascular fat is impaired in a senescence-accelerated prone mouse, compared with control senescence-resistant mice (SAMR1). A long-term treatment with melatonin seems to decrease contractile responses to norepinephrine in mesenteric small arteries of SAMP8, thus restoring an anticontractile effect, probably through antioxidant mechanisms. However, it is not know whether melatonin is able to modulate the production of adiponectin and/or the expression of adiponectin receptors. Therefore, the aim of the study was to investigate the production of adiponectin and/or the expression of adiponectin receptors in the visceral adipose tissue of SAMP8 before and after chronic treatment with melatonin. Design and method: We investigated 7 SAMP8 and 7 SAMR1 treated for 10 months with melatonin (MEL, 10 mg/kg/day), an endogenous indoleamine with antioxidant and vasculoprotective properties, as well as 7 SAMP8 and 7 SAMR1 untreated controls (CTR) kept untreated for 10 months. Visceral fat (perirenal fat) was obtained by dissection, and the adiponectin content, as well as the expression of adiponectin receptor were evaluated by immunohistochemistry. Results: Results are shown in the figure (* p < 0.05 vs SAMR1 CTR; # p < 0.05 vs SAMR1 + MEL; + p < 0.05 vs SAMP8 + MEL). The adiponectin content, as well as the expression of adiponectin receptor were reduced in untreated SAMP8 compared with untreated SAMR1. Treament with MEL was able to increase the production of both proteins in SAMP8. Figure. No caption available. Conclusions: Melatonin treatment is able to increase the production of adiponectin and the expression of adiponectin receptor in the visceral fat of aging mice. This observation might contribute to explain the improvement of the anticontractile action of perivascular fat observed in the mesenteric small resistance arteries of SAMP8 mice after chronic treatment with MEL.

POOR CONCORDANCE BETWEEN NON-INVASIVE AND LOCALLY INVASIVE TECHNIQUES OF EVALUATION OF MICROVASCULAR MORPHOLOGY IN THE DETECTION OF HYPERTROPHIC REMODELING OF SMALL RESISTANCE ARTERIES

Objective: The evaluation of the morphological characteristics of small resistance arteries in human beings is not easy. The gold standard is generally considered to be the evaluation of the media to lumen ratio (MLR) of subcutaneous small vessels obtained by local biopsies and evaluated by wire or pressure micromyiography. However, non-invasive techniques for the evaluation of retinal arterioles were recently proposed, in particular two approaches seem to provide interesting information: scanning laser Doppler flowmetry (SLDF) and adaptive optics (AO); both of them provide an estimation of the wall to lumen ratio (WLR) of retinal arterioles, as well as of internal and external diameters and wall cross-sectional area. Design and method: In the present study we enrolled 12 normotensive subjects, 12 lean hypertensive patients (HP), 9 severely obese normotensive patients (ONP) and 8 severely obese hypertensive patients (OHP), undergoing an election surgical intervention. All patients underwent a biopsy of subcutaneous fat during surgery. Subcutaneous small resistance artery structure was assessed by wire micromyography and the MLR was calculated. WLR of retinal arterioles was obtained by Scanning Laser Doppler Flowmetry and AO (SLDF, Heidelberg Engineering, Heidelberg, Germany and RTX-1, Imagine Eyes, Orsay, France). In hypertensive/obese patients the characteristics of microvascular remodeling were assessed by the calculation of the remodeling and growth indices, according to Heagerty AM et al, Hypertension 1993; 21:391–391). The remodeling index quantifies the proportion of the increase in the MLR or WLR that may be explained by a re-arrangement of the same amount of wall material around a narrowed lumen (eutrophic remodeling), while the growth index quantifies the contribution of vascular smooth muscle cell hypertrophy or hyperplasia (hypertrophic remodeling).When eutrophic remodeling is present, the remodeling index is close to 100%. Results: are reported in the Table. Figure. No caption available. Conclusions: Our data suggest that the three methodological approaches seems are not completely concordant in the detection of hypertrophic remodeling, since data provided are in relative poor agreement. The presence of a relevant proportion of hypertrophic remodeling in obese patients (Hypertension 2011; 58:29–36), observed with micromyographic approaches, is not always confirmed by non-invasive approaches.

REGRESSION OF RETINAL MICROVASCULAR ALTERATIONS IN PATIENTS WITH RHEUMATOID ARTHRITIS TREATED WITH ABATACEPT, AN INHIBITOR OF LYMPHOCYTIC CO-STIMULATION

Objective: It has been previously demonstrated that T lymphocytes may be involved in the development of hypertension and microvascular remodeling, and that circulating T effector lymphocytes may be increased in hypertension (De Ciuceis C et al, Am J Hypertens 2017, 30:51–60; Itani HA et al. Hypertension 2016; 68:123–132). In particular, Th1 and Th 17 lymphocytes may contribute to the progression of hypertension and microvascular damage. Abatacept is a fusion protein composed of the Fc region of the immunoglobulin IgG1 fused to the extracellular domain of CTLA-4 that binds to the CD80 and CD86 molecule, and prevents activation of T cells, avoiding CD28 repetitive engagement. Abatacept is presently indicated for treatment of moderate to severe active rheumatoid arthritis in adults (aged 18 years or over) who have not had an adequate response to other drugs. The aim of our study was to non-invasively investigated morphological characteristics of retinal arterioles in patients with rheumatoid arthritis before and after treatment with abatacept. Design and method: In the present study we enrolled 5 patients with rheumatoid arthritis. The wall to lumen ratio (WLR) of retinal arterioles was measured by adaptive optics (RTX-1, Imagine Eyes, Orsay, France), a recently validated technique (De Ciuceis C, in press in J Hypertens) for non-invasive assessment of retinal arteriolar morphology, providing also an estimation of internal and external diameters and wall cross-sectional area. Morphological evaluations were performed at baseline, after 6 months and after 12 months of treatment Results: The results obtained are reported in the Table (* < 0.05, **p < 0.01 vs. baseline). Figure. No caption available. Conclusions: Our data suggest that a reduction in WLR, wall thickness and wall cross-sectional area was observed after treatment for 12 months with abatacept, thus suggesting the possibility to induce a regression of microvascular abnormalities through a modulation of the immune system.

[PP.09.17] REPRODUCIBILITY OF THE EVALUATION OF THE WALL TO LUMEN RATIO OF RETINAL ARTERIOLES WITH TWO DIFFERENT NON-INVASIVE APPROACHES: SCANNING LASER-DOPPLER FLOWMETRY AND ADAPTIVE OPTICS

Objective: The evaluation of the morphological characteristics of small resistance arteries in human beings in not easy. The gold standard is generally considered to be the evaluation of the media to lumen ratio of subcutaneous small vessels obtained by local biopsies and measured by wire or pressure micromyiography. However, non-invasive techniques for the evaluation of retinal arterioles were recently proposed, in particular two approaches seem to provide interesting information: scanning laser Doppler flowmetry and adaptive optics; both of them provide an estimation of the wall to lumen ratio (WLR) of retinal arterioles. The reproducibility of such measurements was previously stated to be acceptable (coefficient of variation <10% for SLDF, <4% for RTX-1), however, no direct comparison of the two techniques in the same population was previously performed. Design and method: Therefore, we evaluated 18 subjects and patients (10 normotensives, 8 hypertensives, 7/18 severely obese). In all of them an evaluation of the WLR of retinal arterioles was made by Scanning Laser Doppler Flowmetry (SLDF, Heidelberg Engineering, Heidelberg, Germany) and adaptive optics (RTX-1, Imagine Eyes, Orsay, France). The same operator evaluated the same acquired images in two different days (intra-observer variability), and two different operators evaluated the same images in the same day (inter-observer variability). Results: The results are reported in the Table (***p < 0.001). Variation coefficient of SLDF is much greater than that of AO. Figure. No caption available. Conclusions: It is clear how the reproducibility of the evaluation of the WLR with adaptive optics is far better, as compared with SLDF, since the variation coefficient are clearly lower. This may be important in terms of clinical evaluation of microvascular morphology in a clinical setting.

[OP.8C.03] COMPARISON BETWEEN THREE NON-INVASIVE TECHNIQUES OF EVALUATION MICROVASCULAR MORPHOLOGY VS. THE GOLD-STANDARD LOCALLY INVASIVE MICROMYOGRAPHY. PRELIMINARY DATA

Objective: The evaluation of the morphological characteristics of small resistance arteries in human beings in not easy. The gold standard is generally considered to be the evaluation of the media to lumen ratio (M/L) of subcutaneous small vessels obtained by local biopsies and evaluated by wire or pressure micromyiography. However, non-invasive techniques for the evaluation of retinal arterioles were recently proposed, in particular two approaches seem to provide interesting information: scanning laser Doppler flowmetry (SLDF) and adaptive optics (AO); both of them provide an estimation of the wall to lumen ratio (WLR) of retinal arterioles. A non-invasive measurement of basal and total capillary density may be obtained by videomicroscopy/capillaroscopy. No direct comparison of the three non-invasive techniques in the same population was previously performed, in particular AO was never validated against micromyography. Design and method: In the present study we enrolled 12 normotensive subjects and 8 hypertensive patients undergoing an election surgical intervention; 11/20 were severely obese). All patients underwent a biopsy of subcutaneous fat during surgery. Subcutaneous small resistance artery structure was assessed by wire myography and the M/L was calculated. WLR of retinal arterioles was obtained by Scanning Laser Doppler Flowmetry and AO (SLDF, Heidelberg Engineering, Heidelberg, Germany and RTX-1, Imagine Eyes, Orsay, France). Functional (basal) and structural (total) microvascular density were evaluated by capillaroscopy (Videocap 3, DS Medica, Milan, Italy) before and after venous congestion. Results: The results are summarized in the Table (slope of the relation: p < 0.01 RTX-1 vs. SLDF). Figure. No caption available. Conclusions: Our data suggest that AO has a substantial advantage over SLDF in terms of evaluation of microvascular morphology, since it is more closely correlated with the M/L of subcutaneous small arteries, considered a gold-standard approach but limited in its clinical application by the local invasiveness of the procedure.

[OP.7C.11] RELATIONSHIP BETWEEN DIMENSIONS OF THE ASCENDING AORTA AND CLINIC AND 24 HOURS BLOOD PRESSURE IN A GENERAL POPULATION IN NORTHERN ITALY

Objective: Epidemiological studies have suggested that even mild enlargement of the ascending aorta may have independent prognostic significance for cardiovascular events. Therefore, some Authors have proposed that dilatation of the ascending aorta could be considered as a form of preclinical vascular damage in hypertensive patients. Aim of our study: was to assess the correlation between clinic and 24 hours BP values and the dimensions of the aorta, measured at level of the sinuses of Valsalva (Val), at the left ventricular outflow tract (LVOT), and at the level of the proximal ascending aorta (AscAO) in subjects from a general population. Design and method: 250 subjects (43% males, mean age 56 ± 4 years, 42% hypertensives-HT) underwent laboratory examinations, clinic and 24 hours BP measurement, cardiac and carotid ultrasound, carotid-femoral pulse wave velocity measurement (AoPWV). Results: Aortic diameters were greater HT as compared to NT (Val: 3.41 ± 0.54 vs 3.25 ± 0.41 cm, LVOT 2.10 ± 0.28 vs 2.04 ± 0.26, AscAo 3.39 ± 0.45 vs 3.18 ± 0.38, all p < 0.05). Aortic diameters were all correlated to clinic and 24 hours BP values. The coefficients of correlation were greater for 24 hours BP (Tab). Val, AscAo, LVOT were also significantly correlated with left ventricular mass (r = 0.61, r = 0.48, and r = 0.43, all p < 0.001), meanmax intima media thickness (r = 0.13, r = 0.24, and r = 0.13, all p < 0.05) and with AoPWV (r = 0.16, p < 0.05, r = 0.28 p < 0.001, r = 0.08 p = ns). Figure. No caption available. Conclusions: The dimensions of the proximal ascending aorta are significantly related to BP values in normotensive subjects and in hypertensive patients. Aortic dimension are more strictly related to twenty-four hours BP values than to clinic BP values. In this sample of general population a significant correlation between aortic dimensions and measures of cardiac and vascular organ damage was also observed, confirming the parallelism between different forms of organ damage

[PP.21.05] RELATIONSHIP BETWEEN MICROVASCULAR STRUCTURE AND T REGULATORY LYMPHOCYTES OF SMALL RESISTANCE ARTERIES

Objective: Recently it has been demonstrated a role for adaptive immunity, particularly for T regulatory lymphocytes (Tregs), in the development of hypertension and in preventing of angiotensin II–induced vascular injury and inflammation in animal models (Barhoumi T et al, Hypertension 2011;57:469–476). However, no data are presently available in human beings about possible relationships between Tregs and microvascular structural alterations. Design and method: In the present study we enrolled 11 normotensive subjects and 8 hypertensive patients undergoing an election surgical intervention. All patients underwent a biopsy of subcutaneous fat during surgery. Subcutaneous small resistance artery structure was assessed by wire myography and media to lumen ratio (M/L) was calculated. W/L of retinal arterioles was obtained by Scanning Laser Doppler Flowmetry. Functional (basal) and structural (total) microvascular density were studied by capillaroscopy before and after venous congestion. No sign of local or systemic inflammation was present in any subjects or patients. We extracted genomic DNA from small resistance arteries and analyzed methylation status of the FoxP3 gene promoter involved in Treg lymphocytes activation. Unmethylated FoxP3 has been demonstrated to be specific for Treg lymphocytes. A peripheral blood sample was obtained before surgery for routine chemistry Results: Results are summarized in the Table. Figure. No caption available. A significant positive correlation was detected between Tregs in small resistance arteries and basal, total and delta gain capillary density in the forearm, whereas no correlations were observed with small resistance artery M/L and retinal arteriole W/L. In addition, a significant inverse correlation was detected between Treg in subcutaneous small vessels and C reactive protein. Conclusions: Our data suggest that Treg lymphocytes detected in subcutaneous small resistance artery wall are related with capillary density and inversely related with inflammatory markers suggesting a protecting role of Treg also, probably, in terms of angiogenetic properties.

[PP.32.09] EPISTAXIS: RELATIONSHIP WITH CLINIC BLOOD PRESSURE

Objective Background: Epistaxis and hypertension are frequent diseases in the adult population. A relationship between the increase of the blood pressure (BP) and the prevalence and incidence of epistaxis has been suggested (Kikidis et al, 2013). Design and method: Aim of our study was to analyze blood pressure changes in patients with active or recent onset epistaxis (<12 hours) from admission to the emergency department (ED) to discharge. Patients and methods: 126 consecutive subjects (84 males, age range 15–93 years, mean age 67 ± 17 years) admitted to the ED (April 2014-February 2015) with primary epistaxis, were prospectively evaluated. BP was measured with an automatic device (OMRON MT10-E) in accordance to ESH-ESC guidelines 2013; measurements were performed at admission to the ED and 30 minutes after the ear, nose and throat (ENT) specialist visit (and possible hemostasis). Results Results: a diagnosis of hypertension was present in 68% of subjects; 75% of them were on antihypertensive treatment, 35% of them reported adequate BP control, 17% had diabetes mellitus and 25% dyslipidemia. A statistically significant reduction in BP was observed from admission to the ED and to the end of ENT evaluation (from 142 ± 21/84 ± 13 mmHg to 135 ± 21/81 ± 13 mmHg, p = 0.001), while no significant changes were observed in heart rate (from 76 ± 15 to 72 ± 13 b/min). Conclusions Conclusions: results obtained in this group of patients with primary epistaxis show a prevalence of hypertension similar to that of a general population. An accurate BP measurement shows a significant reduction at the end of the ENT specialist evaluation compared to baseline measurement, in both hypertensive and normotensive subjects.

RELATIONSHIP BETWEEN MICROVASCULAR T REGULATORY LYMPHOCYTES AND CIRCULATING LYMPHOCYTES

Objective: Both innate and adaptive immune systems may contribute to the pathogenesis of cardiovascular disease and vascular remodeling through inflammation and oxidative stress. Particularly, the balance between Th1 effector lymphocytes (producing interferon-&ggr;), Th 17 (producing IL-17) and T regulatory (Treg) lymphocytes, which elicit an anti-inflammatory activity, may be crucial for blood pressure elevation and organ damage development, at least in experimental models. Tregs have been previously demonstrated to inversely correlate with subcutaneous small resistance artery media to lumen ratio (M/L) and retinal arteriole wall to lumen ratio (W/L) (unpublished data). Design and method: Therefore, we evaluated the possible relationship between Treg detected in small resistance arteries and circulating levels of Treg. We enrolled 11 normotensive subjects and 4 hypertensive patients undergoing an election surgical intervention (usually removal of adrenal gland for a non-producing adenoma). No sign of local or systemic inflammation was present in any subjects or patients. All patients underwent a biopsy of subcutaneous fat during surgery and small resistance arteries were isolated. We extracted genomic DNA from small resistance arteries and analyzed methylation status of the FoxP3 gene promoter involved in Treg lymphocytes activation. Unmethylated FoxP3 has been demonstrated to be specific for Treg lymphocytes. A peripheral blood sample was obtained before surgery for assessment of T lymphocyte subpopulations. Lymphocyte phenotype was evaluated by flow cytometry after 5 days in vitro activation in order to assess Th17 lymphocytes. Results: A significant positive correlation was detected between Treg in small resistance arteries and circulating levels of Treg (R = 0.42, p∼0.05) whereas an inverse correlation was observed between Th17 lymphocytes and Treg in small resistance arteries (R = -0.46, p < 0.05). Conclusions: Our data suggest that Treg lymphocytes detected in subcutaneous small resistance artery wall are related to circulating Treg which were previously observed to inversely correlate with subcutaneous small resistance artery media to lumen ratio and retinal arteriole wall to lumen ratio. This suggest that Treg may be protective against microvascular damage confirming an involvement of adaptive immune system on microvascular remodeling.

Correlation between wall-to-lumen ratio of retinal arterioles and clinic and 24 hours blood pressure

Objective: Wall-to-lumen ratio of retinal arterioles might serve as an in-vivo parameter of vascular damage. Previuos studies have shown a correlation between retinal arteriolar structure and blood pressure values, measured both in the clinic and during 24 hours ambulatory monitoring. We analyzed the impact of brachial clinic blood pressure (BP), of central BP and of 24 hours BP values on wall-to-lumen ratio of retinal arterioles. Methods: In 267 subjetcts (129 males, age range 20-72 years; mean 54±7 years) wall-to-lumen ratio of retinal arterioles was assessed in vivo using scanning laser doppler flowmetry (Heidelberg retina flowmeter, Heidelberg Engeneering). In addition clinic and 24 hours BP values were measured. Central hemodynamics and augmentation index (Ai) were assessed by pulse wave analysis. Results: In never treated patients with essential hypertension (n = 56) a higher wall-to-lumen ratio (0.37±0.19 vs. 0.30±0.13, P=0.05) was observed in comparison with normotensive individuals (n = 115); no significant differences were observed between treated (n=96) and untreated hypertensive patients. Wall to lumen ratio and wall cross sectional area of retinal arterioles were significantly related to clinic systolic BP (r=0.23, P=0.005) and PP (r=0.18, P=0.005), to 24 hours systolic BP (r=0.28, P=0.0001)and PP (r=0.19, P=0.003) and to central systolic BP (r=0.20, P=0.01) and central PP (r=0.21, P=0.001). Multiple regression analysis including all BP indices revealed that only mean systolic 24 hours BP is independently associated with an increased wall-to-lumen ratio of retinal arterioles. Conclusion: In this quite large group of hypertensive patients and normotensive individuals 24 hours systolic BP seems to be the strongest determinant of increased WLR of retinal arterioles.