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Journal of the American Heart... Nov 2020Background Long-term feeding with a high-fat diet (HFD) induces endothelial dysfunction in mice, but early HFD-induced effects on endothelium have not been well...
In Vivo Magnetic Resonance Imaging-Based Detection of Heterogeneous Endothelial Response in Thoracic and Abdominal Aorta to Short-Term High-Fat Diet Ascribed to Differences in Perivascular Adipose Tissue in Mice.
Background Long-term feeding with a high-fat diet (HFD) induces endothelial dysfunction in mice, but early HFD-induced effects on endothelium have not been well characterized. Methods and Results Using an magnetic resonance imaging-based methodology that allows characterization of endothelial function in vivo, we demonstrated that short-term (2 weeks) feeding with a HFD to mice or to mice resulted in the impairment of acetylcholine-induced response in the abdominal aorta (AA), whereas, in the thoracic aorta (TA), the acetylcholine-induced response was largely preserved. Similarly, HFD resulted in arterial stiffness in the AA, but not in the TA. The difference in HFD-induced response was ascribed to distinct characteristics of perivascular adipose tissue in the TA and AA, related to brown- and white-like adipose tissue, respectively, as assessed by histology, immunohistochemistry, and Raman spectroscopy. In contrast, short-term HFD-induced endothelial dysfunction could not be linked to systemic insulin resistance, changes in plasma concentration of nitrite, or concentration of biomarkers of glycocalyx disruption (syndecan-1 and endocan), endothelial inflammation (soluble form of vascular cell adhesion molecule 1, soluble form of intercellular adhesion molecule 1 and soluble form of E-selectin), endothelial permeability (soluble form of fms-like tyrosine kinase 1 and angiopoietin 2), and hemostasis (tissue plasminogen activator and plasminogen activator inhibitor 1). Conclusions Short-term feeding with a HFD induces endothelial dysfunction in the AA but not in the TA, which could be ascribed to a differential response of perivascular adipose tissue to a HFD in the AA versus TA. Importantly, early endothelial dysfunction in the AA is not linked to elevation of classical systemic biomarkers of endothelial dysfunction.
Topics: Adipose Tissue; Animals; Aorta, Abdominal; Aorta, Thoracic; Diet, High-Fat; Endothelium, Vascular; Magnetic Resonance Imaging; Male; Mice; Mice, Inbred C57BL
PubMed: 33073641
DOI: 10.1161/JAHA.120.016929 -
Journal of Cardiovascular Magnetic... Sep 2019Cine fast interrupted steady-state in combination with arterial spin labeling is a recently described nonenhanced magnetic resonance angiography (MRA) technique that... (Comparative Study)
Comparative Study
Dynamic quantitative nonenhanced magnetic resonance angiography of the abdominal aorta and lower extremities using cine fast interrupted steady-state in combination with arterial spin labeling: a feasibility study.
BACKGROUND
Cine fast interrupted steady-state in combination with arterial spin labeling is a recently described nonenhanced magnetic resonance angiography (MRA) technique that relies on bolus tracking for time-resolved digital subtraction angiography-like displays of blood flow patterns. We evaluated the feasibility of applying this technique to display in-plane flow patterns in two regions: the abdominal aorta and lower extremity peripheral arteries.
METHODS
We performed an institutional review board-approved study in healthy subjects and patients. In 7 healthy subjects, in-plane flow was imaged at 4 stations ranging from the lower legs to the aorto-iliac bifurcation (junction of the distal thigh and upper calf, mid-thigh, junction of the upper thigh and pelvis, upper pelvis). In 5 healthy subjects and 6 patients without abdominal aortopathy, images were acquired through the suprarenal abdominal aorta. Ten patients with known peripheral arterial disease and two patients with stable disease of the abdominal aorta were also evaluated. Peak velocity was compared at each of the 4 stations for cine fast interrupted steady-state in combination with arterial spin labeling and two-dimensional cine phase contrast in patients with normal vessels.
RESULTS
In-plane flow patterns were well visualized in all peripheral arterial stations and in the abdominal aorta, providing a high quality display of hemodynamic patterns along extensive lengths of the vessels. There was very strong positive correlation (r = 0.952, P < 0.05) and excellent agreement (intraclass correlation coefficient, 0.935; 95% confidence interval, 0.812-0.972) between peak flow velocities measured by cine fast interrupted steady-state in combination with arterial spin labeling and two-dimensional cine phase contrast. In 10 patients with peripheral artery disease and 2 patients with aortic pathology, cine fast interrupted steady-state in combination with arterial spin labeling provided a visual demonstration of abnormal hemodynamics.
CONCLUSION
This feasibility study suggests that cine fast interrupted steady-state in combination with arterial spin labeling provides an efficient, high quality and physiologically accurate display of in-plane flow patterns over extensive lengths of the lower extremity peripheral arteries, which can be difficult to achieve using other MRA techniques.
Topics: Adult; Aged; Aged, 80 and over; Aorta, Abdominal; Blood Flow Velocity; Case-Control Studies; Cineangiography; Feasibility Studies; Female; Humans; Lower Extremity; Magnetic Resonance Angiography; Male; Middle Aged; Perfusion Imaging; Predictive Value of Tests; Regional Blood Flow; Reproducibility of Results; Spin Labels; Time Factors; Vascular Diseases
PubMed: 31474219
DOI: 10.1186/s12968-019-0562-3 -
The Journal of Thoracic and... Nov 2008Vascular remodeling within the aorta results in a loss of structural integrity with consequent aneurysm formation. This degradation is more common in the abdominal aorta... (Review)
Review
Vascular remodeling within the aorta results in a loss of structural integrity with consequent aneurysm formation. This degradation is more common in the abdominal aorta but also occurs above the diaphragm in the thoracic aorta. Conventionally, the aorta has been considered a large vascular conduit with uniform cellular and extracellular structure and function. Evidence is accumulating, however, to suggest that variations exist between the thoracic and abdominal aorta, thereby demonstrating regional heterogeneity. Further pathophysiologic studies of aortic dilation in each of these regions have identified disparities in atherosclerotic plaque deposition, vessel mechanics, protease profiles, and cell-signaling pathways. Improved understanding of this spatial heterogeneity might promote evolution in the management of aneurysm disease through computational models of aortic wall stress, imaging of proteolytic activity, targeted pharmacologic treatment, and application of region-specific gene therapy.
Topics: Aorta, Abdominal; Aorta, Thoracic; Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Humans
PubMed: 19026791
DOI: 10.1016/j.jtcvs.2008.06.027 -
Journal of Vascular Surgery Jan 2017This review describes ongoing efforts to develop a medical therapy to limit abdominal aortic aneurysm (AAA) growth. (Review)
Review
OBJECTIVE
This review describes ongoing efforts to develop a medical therapy to limit abdominal aortic aneurysm (AAA) growth.
METHODS
Data from animal model studies, human investigations, and clinical trials are described.
RESULTS
Studies in rodent models and human samples have suggested a number of potential targets for slowing or halting AAA growth. A number of clinical trials are now examining the value of medications targeting some of the pathways identified. These trials have a number of challenges, including identifying medications safe to use in older patients with multiple comorbidities, developing accurate outcome assessments, and minimizing the dropout of patients during the trials. Three recent trials have reported no benefit of the antibiotic doxycycline, a mast cell inhibitor, an angiotensin-converting enzyme inhibitor, or a calcium channel blocker in limiting AAA growth. A number of other trials examining angiotensin receptor blockers, cyclosporine, and an antiplatelet agent are currently underway.
CONCLUSIONS
Further refinement of drug discovery pathways and testing paradigms are likely needed to develop effective nonsurgical therapies for AAA.
Topics: Animals; Aorta, Abdominal; Aortic Aneurysm, Abdominal; Cardiovascular Agents; Dilatation, Pathologic; Disease Progression; Drug Discovery; Humans
PubMed: 27641464
DOI: 10.1016/j.jvs.2016.08.003 -
Journal of Visualized Experiments : JoVE Feb 2022Abdominal aortic aneurysm (AAA), although primarily asymptomatic, is potentially life-threatening as the rupture of AAA usually has a devastating outcome. Currently,...
Abdominal aortic aneurysm (AAA), although primarily asymptomatic, is potentially life-threatening as the rupture of AAA usually has a devastating outcome. Currently, there are several distinct experimental models of AAA, each emphasizing a different aspect in the pathogenesis of AAA. The elastase-induced AAA model is the second most used rodent AAA model. This model involves direct infusion or application of porcine pancreatic elastase (PPE) to the infrarenal segment of the aorta. Due to technical challenges, most elastase-induced AAA model nowadays is performed with the external application rather than an intraluminal infusion of PPE. The infiltration of elastase will cause degradation of elastic lamellae in the medial layers, resulting in the loss of aortic wall integrity and subsequent dilation of the abdominal aorta. However, one disadvantage of the elastase-induced AAA model is the inevitable variation of how the surgery is performed. Specifically, the surgical technique of isolating the infrarenal segment of the aorta, the material used for aorta wrapping and PPE incubation, the enzymatic activity of PPE, and the time duration of PPE application can all be important determinants that affect the eventual AAA formation rate and aneurysm diameter. Notably, the difference in these factors from different studies on AAA can lead to reproducibility issues. This article describes a detailed surgical process of the elastase-induced AAA model through direct application of PPE to the adventitia of the infrarenal abdominal aorta in the mouse. Following this procedure, a stable AAA formation rate of around 80% in male and female mice is achievable. The consistency and reproducibility of AAA studies using an elastase-induced AAA model can be significantly enhanced by establishing a standard surgical procedure.
Topics: Animals; Aorta, Abdominal; Aortic Aneurysm, Abdominal; Disease Models, Animal; Female; Male; Mice; Mice, Inbred C57BL; Pancreatic Elastase; Reproducibility of Results; Swine
PubMed: 35225256
DOI: 10.3791/63608 -
Journal of Ultrasound Mar 2020Information on the relationship between the diameters of the abdominal aorta (AA) and the basilar artery (BA) is limited. Using the Atahualpa Project cohort, we aimed to...
INTRODUCTION
Information on the relationship between the diameters of the abdominal aorta (AA) and the basilar artery (BA) is limited. Using the Atahualpa Project cohort, we aimed to assess this association in Atahualpa residents aged ≥ 60 years.
MATERIALS AND METHODS
Atahualpa residents aged ≥ 60 years underwent abdominal ultrasound and MRA of intracranial vessels. The independent association between both arterial diameters was estimated in a generalized linear model adjusted for demographics, cardiovascular risk factors, the presence of a fetal-type Circle of Willis, and severity of white matter hyperintensities. Fractional polynomials were fitted to model the relationship between AA and BA diameters.
RESULTS
The mean age of 277 participants was 69.5 ± 7.7 years (61% women). The mean AA diameter was 19.8 ± 3.3 mm, and the mean BA diameter was 3.1 ± 0.7 mm. The mean diameters of both arteries were significantly higher in men than in women. Locally weighted scatterplot smoothing showed a non-linear relationship between both arterial diameters. Fractional polynomial models showed that AA and BA diameters had a significant non-linear association in men (p = 0.005), but not in women (p = 0.315). When sex was excluded from a generalized linear model, the relationship between both arterial diameters became significant (p = 0.017).
CONCLUSION
In this population of community-dwelling older adults, the relationship between AA and BA diameters was confined to men. The finding of a large AA diameter in men should prompt the investigation of the intracranial vasculature because of the possibility of BA ectasia.
Topics: Aged; Aorta, Abdominal; Basilar Artery; Ecuador; Ethnicity; Female; Humans; Linear Models; Magnetic Resonance Angiography; Male; Middle Aged; Models, Statistical; Neuroimaging; Risk Factors; Sex Characteristics; Ultrasonography
PubMed: 30414081
DOI: 10.1007/s40477-018-0338-x -
Scientific Reports Mar 2021Microvascular anastomosis is a critical procedure in cerebral bypass surgeries. In some rare cases, the extraluminal interrupted technique is not optimal because the...
Microvascular anastomosis is a critical procedure in cerebral bypass surgeries. In some rare cases, the extraluminal interrupted technique is not optimal because the vessels are immobile and cannot be rotated, and anastomosis can be performed effectively through the intraluminal continuous suturing technique. The authors reported the application of the intraluminal continuous suturing technique in microanastomosis training with silicone tube, rat's common iliac arteries and abdominal aorta. A silicone tube with a diameter of 1.5 mm was used to practice microanastomosis in intraluminal continuous suturing technique. Then the technique was applied in side-to-side, end-to-side anastomoses of common iliac arteries and the end-to-end abdominal aorta anastomoses of rat. The suturing time and patency rates were compared with an alternative intraluminal continuous suturing technique and one-way-up interrupted suturing technique in silicone tube and rat vessel anastomoses. The intraluminal continuous suturing technique could be gained through practicing with silicone tube, and the technique has also been demonstrated effective in side-to-side, end-to-side anastomoses of common iliac arteries of rat and the abdominal aorta end-to-end anastomoses. In all the animal experimental groups with different suturing techniques, there was no difference between the patency rates, all the immediate patency rate was 100%. There was no significant suturing time difference between the two intraluminal continuous suturing techniques, but the two intraluminal continuous suturing techniques were faster than the interrupted technique. The intraluminal continuous suturing technique described in the study could be used as an efficient method for side-to-side, end-to-side and end-to-end anastomosis, especially under the situation the posterior wall of the anastomosis could not be rotated. Proficiency of the technique could be achieved through practicing in laboratory with silicone tube and live animals.
Topics: Anastomosis, Surgical; Animals; Aorta, Abdominal; Iliac Artery; Microsurgery; Rats; Sutures; Vascular Surgical Procedures
PubMed: 33649423
DOI: 10.1038/s41598-021-84619-6 -
Life Sciences Aug 2018The biguanide metformin (MET) has been used during pregnancy for treatment of polycystic ovary syndrome and gestational diabetes. MET crosses the placenta and maternal...
The biguanide metformin (MET) has been used during pregnancy for treatment of polycystic ovary syndrome and gestational diabetes. MET crosses the placenta and maternal treatment can expose the progeny to this drug during important phases of body development. Direct vascular protective effects have been described with the treatment of metformin. Nevertheless, it is unclear whether intrauterine exposure to metformin is safe for the vascular system of offspring. Thus, the present study aimed to investigate the intrinsic effects of metformin exposure in utero in the offspring abdominal aorta reactivity, in the presence and absence of perivascular adipose tissue (PVAT) and endothelium. For this, Wistar rats were treated with metformin 293 mg/kg/day (MET) or water (CTR) by gavage during the gestational period. The abdominal aorta reactivity to phenylephrine, acetylcholine, and sodium nitroprusside was evaluated in male adult offspring. It was observed that abdominal aorta relaxation was similar between MET and CTR groups in the presence or absence of PVAT. In addition, the contraction to phenylephrine was similar between MET and CTR groups in the presence and absence of PVAT and endothelium. Therefore, metformin exposure during pregnancy had no intrinsic effect on the offspring abdominal aorta PVAT and endothelial function, demonstrating it to be safe to the vascular system of the offspring.
Topics: Adipose Tissue; Animals; Aorta, Abdominal; Body Weight; Dose-Response Relationship, Drug; Endothelial Cells; Endothelium, Vascular; Female; Male; Maternal Exposure; Metformin; Nitroprusside; Pregnancy; Pregnancy, Animal; Prenatal Exposure Delayed Effects; Rats; Rats, Wistar; Vasoconstriction; Vasodilation
PubMed: 29852188
DOI: 10.1016/j.lfs.2018.05.050 -
Cardiovascular Pathology : the Official... 2024Abdominal aortic aneurysm is a weakening and expansion of the abdominal aorta. Currently, there is no drug treatment to limit abdominal aortic aneurysm growth. The... (Review)
Review
BACKGROUND
Abdominal aortic aneurysm is a weakening and expansion of the abdominal aorta. Currently, there is no drug treatment to limit abdominal aortic aneurysm growth. The glycocalyx is the outermost layer of the cell surface, mainly composed of glycosaminoglycans and proteoglycans.
OBJECTIVE
The aim of this review was to identify a potential relationship between glycocalyx disruption and abdominal aortic aneurysm pathogenesis.
METHODS
A narrative review of relevant published research was conducted.
RESULTS
Glycocalyx disruption has been reported to enhance vascular permeability, impair immune responses, dysregulate endothelial function, promote extracellular matrix remodeling and modulate mechanotransduction. All these effects are implicated in abdominal aortic aneurysm pathogenesis. Glycocalyx disruption promotes inflammation through exposure of adhesion molecules and release of proinflammatory mediators. Glycocalyx disruption affects how the endothelium responds to shear stress by reducing nitric oxide availabilty and adversely affecting the storage and release of several antioxidants, growth factors, and antithromotic proteins. These changes exacerbate oxidative stress, stimulate vascular smooth muscle cell dysfunction, and promote thrombosis, all effects implicated in abdominal aortic aneurysm pathogenesis. Deficiency of key component of the glycocalyx, such as syndecan-4, were reported to promote aneurysm formation and rupture in the angiotensin-II and calcium chloride induced mouse models of abdominal aortic aneurysm.
CONCLUSION
This review provides a summary of past research which suggests that glycocalyx disruption may play a role in abdominal aortic aneurysm pathogenesis. Further research is needed to establish a causal link between glycocalyx disruption and abdominal aortic aneurysm development.
Topics: Glycocalyx; Aortic Aneurysm, Abdominal; Humans; Animals; Aorta, Abdominal; Oxidative Stress; Mechanotransduction, Cellular; Capillary Permeability; Signal Transduction; Vascular Remodeling
PubMed: 38461960
DOI: 10.1016/j.carpath.2024.107629 -
Asian Journal of Surgery Apr 2024
Topics: Humans; Aorta, Abdominal; Bronchogenic Cyst; Stomach; Abdomen
PubMed: 38262794
DOI: 10.1016/j.asjsur.2023.12.126