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PloS One 2020Aging causes stiffness and decreased function of the renal artery (RA). Histological study with light microscopy can reveal microscopic structural remodeling but no...
OBJECTIVES
Aging causes stiffness and decreased function of the renal artery (RA). Histological study with light microscopy can reveal microscopic structural remodeling but no functional changes. The present study aimed to clarify the association between structural and functional aging of the RA through the use of scanning acoustic microscopy.
METHODS
Formalin-fixed, paraffin-embedded cross-sections of renal arteries from 64 autopsy cases were examined. Speed-of-sound (SOS) values of three layers, which correspond to the stiffness, were compared among different age groups. SOS of the tunica media was examined in terms of blood pressure (BP) and SOS of the ascending aorta. Vulnerability to proteases was assessed by SOS reduction after collagenase treatment.
RESULTS
The tunica intima presented inward hypertrophy with luminal narrowing, and the tunica media showed outward hypertrophic remodeling with aging. SOS of the tunica media and internal and external elastic laminae showed a reverse correlation with age. SOS of the tunica media was negatively correlated with BP and strongly associated with that of the aorta. The tunica media of young RAs were more sensitive to collagenase compared with the old ones.
CONCLUSIONS
Scanning acoustic microscopy is useful for observing the aging process of the RA. This technique simultaneously shows structural and mechanical information from each portion of the RA. In the process of aging, the RA loses contractile function and elasticity as a result of protease digestion. The tunica media and the internal and external elastic laminae exhibit reduced stiffness, but the tunica intima stiffens with atherosclerosis. As a consequence, the RA's outer shape changes from round to oval with inward and outward hypertrophy. This indicates that the inner resistant intima supports the mechanical weakness of the tunica media to compensate for an increase in BP with aging.
Topics: Adult; Aged, 80 and over; Aging; Autopsy; Blood Pressure; Female; Humans; Male; Microscopy, Acoustic; Renal Artery; Tunica Intima; Tunica Media
PubMed: 33147291
DOI: 10.1371/journal.pone.0234759 -
Cardiovascular Diabetology May 2022Individuals with type 2 diabetes mellitus (T2DM) have an increased risk for developing macrovascular disease (MVD) manifested by atherosclerosis. Phenotypically and...
BACKGROUND
Individuals with type 2 diabetes mellitus (T2DM) have an increased risk for developing macrovascular disease (MVD) manifested by atherosclerosis. Phenotypically and functionally different monocyte subsets (classical; CD14CD16, non-classical; CD14CD16, and intermediate; CD14CD16) including pro-angiogenic monocytes expressing Tie2 (TEMs) can be identified. Here we investigated monocyte heterogeneity and its association with T2DM and MVD.
METHODS
Individuals with (N = 51) and without (N = 56) T2DM were recruited and allocated to "non-MVD" or "with MVD" (i.e., peripheral or coronary artery disease) subgroups. Blood monocyte subsets were quantified based on CD14, CD16 and Tie2 expression levels. Plasma levels of Tie2-ligands angiopoietin-1 and angiopoietin-2 were determined using ELISA. Carotid endarterectomy samples from individuals with (N = 24) and without (N = 22) T2DM were stained for intraplaque CD68 macrophages (inflammation) and CD34 (angiogenesis), as plaque vulnerability markers.
RESULTS
Monocyte counts were similar between individuals with T2DM and healthy controls (non-diabetic, non-MVD). Non-classical monocytes were reduced (p < 0.05) in T2DM, whereas the percentage of TEMs within the intermediate subset was increased (p < 0.05). T2DM was associated with increased angiopoietin-1 (p < 0.05) and angiopoietin-2 (p = 0.0001) levels. Angiopoietin-2 levels were higher in T2DM individuals with MVD compared with non-MVD (p < 0.01). Endarterectomized plaques showed no differences in macrophage influx and microvessel number between individuals with and without T2DM.
CONCLUSIONS
Monocyte subset distribution is altered in T2DM with reduced non-classical monocytes and increased TEM percentage in the intermediate monocyte subset. Increased angiopoietin-2 levels together with increased frequency of TEMs might promote plaque vulnerability in T2DM which could however not be confirmed at tissue level in advanced atherosclerotic lesions.
Topics: Angiopoietin-1; Angiopoietin-2; Atherosclerosis; Diabetes Mellitus, Type 2; Humans; Monocytes; Plaque, Atherosclerotic; Receptor, TIE-2; Tunica Intima
PubMed: 35549955
DOI: 10.1186/s12933-022-01497-6 -
Circulation Research Nov 1999
Review
Topics: Animals; Arteriosclerosis; Carotid Artery, Internal; Humans; Tunica Intima
PubMed: 10559132
DOI: 10.1161/01.res.85.10.877 -
Hospital Practice (1995) Apr 2013Carotid artery intima-media thickness (IMT) is a biomarker for cardiovascular disease that also predicts the risk of cardiovascular mortality. Angiotensin-converting... (Review)
Review
Carotid artery intima-media thickness (IMT) is a biomarker for cardiovascular disease that also predicts the risk of cardiovascular mortality. Angiotensin-converting enzyme (ACE) inhibition is a unique therapeutic modality because it both treats hypertension and improves arterial health and cardiovascular disease outcomes. Controversy exists regarding the role of ACE inhibitors and angiotensin receptor blockers (ARBs) in IMT regression. Our article provides an update on how ACE inhibitors and ARBs could play a role in decreasing IMT.
Topics: Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Cardiovascular Diseases; Carotid Arteries; Humans; Renin-Angiotensin System; Risk Assessment; Tunica Intima
PubMed: 23680737
DOI: 10.3810/hp.2013.04.1026 -
Folia Morphologica Aug 2010The structural organisation of tunica intima in the aorta is important for its integrity, prediction, and diagnosis of atherosclerosis. The goat is a suitable model for...
The structural organisation of tunica intima in the aorta is important for its integrity, prediction, and diagnosis of atherosclerosis. The goat is a suitable model for cardiovascular studies, but the structure of its tunica intima is scarcely reported. This study, therefore, aimed to describe features of the goat aortic tunica intima by light and transmission electron microscopy. Sixteen healthy male domestic goats (capra hircus) aged between 6 and 24 months were used: 8 for light and 8 for electron microscopy. The animals were euthanised with sodium pentabarbitone 20 mg/mL and fixed with 3% phosphate buffered glutaraldehyde. For light microscopy, specimens from various regions of the aorta were routinely processed for paraffin embedding and 7 mm sections stained with Mason's trichrome. Those for transmission electron microscopy were post fixed in osmium tetroxide, embedded in Durcupan, and ultrathin sections stained with uranyl acetate and counter stained with lead citrate. Endothelium comprises round and squamous cells, linked to the subendothelial material by a simple and sometimes lamellated basement membrane. In the subendothelial zone, a heterogenous population of cells are connected with interlinked collagen and elastic fibres. Both cells and fibres are connected to the internal elastic lamina. The composite structure and interlinkages in the tunica intima permit unitary function and increase mechanical strength, thus enabling it to withstand haemodynamic stress.
Topics: Animals; Aorta; Endothelium, Vascular; Goats; Hemodynamics; Male; Microscopy; Microscopy, Electron, Transmission; Tunica Intima
PubMed: 21154287
DOI: No ID Found -
Ultraschall in Der Medizin (Stuttgart,... Oct 2009
Review
Topics: Arteriosclerosis; Humans; Prognosis; Risk Factors; Stroke; Tunica Intima; Tunica Media; Ultrasonography
PubMed: 19813155
DOI: 10.1055/s-0028-1109797 -
Journal of the American Society of... Aug 2011
Topics: Atherosclerosis; Carotid Arteries; Carotid Intima-Media Thickness; Humans; Practice Guidelines as Topic; Predictive Value of Tests; Risk Assessment; Risk Factors; Sensitivity and Specificity; Tunica Intima; Tunica Media
PubMed: 21791274
DOI: 10.1016/j.echo.2011.06.012 -
The International Journal of... Mar 2022The long saphenous vein is commonly used in cardiac surgery to bypass occluded coronary arteries. Its use is complicated by late stenosis and occlusion due to the... (Review)
Review
The long saphenous vein is commonly used in cardiac surgery to bypass occluded coronary arteries. Its use is complicated by late stenosis and occlusion due to the development of intimal hyperplasia. It is accepted that intimal hyperplasia is a multifactorial inflammatory process that starts immediately after surgery. The role of acute changes in haemodynamic conditions when the vein is implanted into arterial circulation, especially shear stress, is not fully appreciated. This review provides an overview of intimal hyperplasia and the effect of acute shear stress changes on the activation of pro-inflammatory mediators.
Topics: Coronary Vessels; Humans; Hyperplasia; Saphenous Vein; Stress, Mechanical; Tunica Intima; Vascular Diseases
PubMed: 35151879
DOI: 10.1016/j.biocel.2022.106173 -
Current Medicinal Chemistry 2009Carotid artery intima-media thickness measured by ultrasound has been shown to be correlated with the presence of cardiovascular disease and is now accepted and used as... (Review)
Review
Carotid artery intima-media thickness measured by ultrasound has been shown to be correlated with the presence of cardiovascular disease and is now accepted and used as a surrogate marker for atherosclerotic disease, an important organ damage of hypercholesterolemia. In particular, statins reduce ischemic heart disease, improve endothelial function, reduce pro-inflammatory cytokines, reduce left ventricular hypertrophy and adverse remodeling, and slow/arrest atherosclerotic process. This last effect represents one of the most important targets of lipid-lowering drugs, in particular, carotid intima-media thickness, and an early-onset of atherosclerotic process. The acute anti-inflammatory effects of statins should further be explored as a potential mediator of change in intima-media thickness. Larger randomized controlled trials with selected patients and more detailed measurements of carotid intima-media thickness are needed to determine the clinical practice implications of these findings in participants who have asymptomatic evidence of atherosclerosis. The aim of this review is to explore the effectiveness of several used statins on carotid intima-media thickness regression.
Topics: Carotid Arteries; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Tunica Intima
PubMed: 19442146
DOI: 10.2174/092986709788186183 -
Cardiovascular Research Apr 2020This review seeks to provide an update of preclinical findings and available clinical data on the chronic persistent inflammation and its direct role on the pulmonary... (Review)
Review
This review seeks to provide an update of preclinical findings and available clinical data on the chronic persistent inflammation and its direct role on the pulmonary arterial hypertension (PAH) progression. We reviewed the different mechanisms by which the inflammatory and immune pathways contribute to the structural and functional changes occurring in the three vascular compartments: the tunica intima, tunica media, and tunica adventitia. We also discussed how these inflammatory mediator changes may serve as a biomarker of the PAH progression and summarize unanswered questions and opportunities for future studies in this area.
Topics: Adventitia; Animals; Arterial Pressure; Autoimmunity; Chronic Disease; Disease Progression; Humans; Inflammation Mediators; Pulmonary Arterial Hypertension; Pulmonary Artery; Signal Transduction; Tunica Intima; Tunica Media; Vascular Remodeling; Vasculitis
PubMed: 31813986
DOI: 10.1093/cvr/cvz308