Elevation of ADAM10, ADAM17, MMP-2 and MMP-9 expression with media degeneration features CaCl2-induced thoracic aortic aneurysm in a rat model.

PURPOSE: This study was designed to establish a rat model of thoracic aortic aneurysm (TAA) by calcium chloride (CaCl(2))-induced arterial injury and to explore the potential role of a disintegrin and metalloproteinase (ADAM), matrix metalloproteinases (MMPs) and their endogenous inhibitors (TIMPs) in TAA formation. METHODS: Thoracic aorta of male Sprague-Dawley rats was exposed to 0.5M CaCl(2) or normal saline (NaCl). After 12weeks, animals were euthanized, and CaCl(2)-treated, CaCl(2)-untreated (n=12) and NaCl-treated aortic segments (n=12) were collected for histological and molecular assessments. MMP-TIMP and ADAM mRNAs were semi-quantitatively analyzed and protein expressions were determined by immunohistochemistry. RESULTS: Despite similar external diameters among CaCl(2)-treated, non-CaCl(2)-treated and NaCl-treated segments, aneurymal alteration (n=6, 50%), media degeneration with regional disruption, fragmentation of elastic fiber, and increased collagen deposition (n=12, 100%) were demonstrated in CaCl(2)-treated segments. MMP-2, MMP-9, ADAM-10 and ADAM-17 mRNA levels were increased in CaCl(2)-treated segments (all p<0.01), with trends of elevation in CaCl(2)-untreated segments, as compared with NaCl-treated segments. Immunohistochemistry displayed significantly increased expressions of MMP-2, MMP-9, ADAM-10 and ADAM-17 (all p<0.01) in intima and media for CaCl(2)-treated segments. TIMP mRNA and tissue levels did not differ obviously among the three aortic segments. CONCLUSION: This study establishes a TAA model by periarterial CaCl(2) exposure in rats, and demonstrates a significant elevation of expression of MMP-2, MMP-9, ADAM10 and ADAM17 in the pathogenesis of vascular remodeling.

[Efficacy of shenfu injection as adjuvant therapy in treating patients of ischemic cardiomyopathy with heart insufficiency].

OBJECTIVE: To evaluate the clinical efficacy of Shenfu Injection (SFI), as a adjuvant therapy, in treating patients of ischemic cardiomyopathy with heart insufficiency (ICP-HI). METHODS: One hundred patients of ICP-HF were equally randomized into two groups, the SFI group and the control group. All received the conventional treatment, but to patients in the SFI group SFI was given additionally via intravenous injection, 60 mL once a day, 10 days each month, the treatment course was 6 months. Changes of cardial functional grading, 6-min walking distance, echocardiographic indices, plasma N terminal pro-brain natriuretic peptide (pro-BNP) level were observed before and after treatment, and the occurrence of major adverse cardiovascular events (MACE) and mortality in patients were observed as well. RESULTS: As compared with the conventional treatment alone, additional application of SFI showed a more significant efficacy in improving NYHA functional grade and 6-min walking distance, reducing the diameters of left ventricular at end diastole and systole, increasing left ventricular ejection fraction, and decreasing plasma N terminal pro-BNP level (P <0.05). The occurrence of MACE and the mortality in the SFI group were significantly lower than those in the control group respectively (P <0.05). CONCLUSIONS: Based on the conventional treatment, the adjuvant therapy of SFI could improve the cardiac function, improve the quality of life, ameliorate ventricular reconstruction, and decrease the occurrence of cardiovascular events in patients of ICP-HI.

[Quantitative evaluation of ischemic myocardium by adenosine tissue Doppler stress echocardiography.].

OBJECTIVE: To evaluate the value of adenosine tissue Doppler stress echocardiography on ischemic myocardium. METHODS: Routine dosage (140 microgxkg(-1)xmin(-1) IV for 6 min) adenosine stress echocardiography was performed on 40 patients with chest pain for diagnosis of coronary artery disease (CAD). The images of left ventricular myocardial motion were acquired by tissue Doppler imaging (TDI) based on traditional 2D stress echocardiography before and 3 min, 6 min after adenosine stress (GE Vivid 7, USA). The myocardial velocity, strain and strain rate in 16 segments were offline measured and analyzed on ECHOPAC software. The results were compared with that of coronary angiography (CAG). RESULTS: CAG identified 18 CAD and 22 non-CAD patients with 159 ischemic segments and 465 non-ischemic segments. Adenosine significantly increased the systolic velocity (Sm), early diastolic velocity (Em), late diastolic velocity (Am), peak systolic strain (Smax), systolic strain rate (SRs), early diastolic strain rate (SRe) and late diastolic strain rate (SRa) both ischemic and non-ischemic segments (all P < 0.05). The baseline Sm and Em in ischemic segments were significant lower than non-ischemic segments [(3.16 +/- 1.20) cm/s vs (4.03 +/- 1.27) cm/s, P < 0.01; (3.75 +/- 1.67) cm/s vs (4.66 +/- 1.70) cm/s, P < 0.05]. At peak stress the differences in Sm and Em were more significant [(3.98 +/- 1.63) cm/s vs (5.07 +/- 1.52) cm/s; (4.51 +/- 2.32) cm/s vs (6.52 +/- 2.56) cm/s; P < 0.01]. The reductions on Smax and Se were more significant in ischemic segments compared those in non-ischemic segments (16.91% +/- 3.35% vs 19.56% +/- 5.47%, P < 0.01 and 9.53% +/- 2.89% vs 13.06% +/- 4.63%, P < 0.001). The biggest area under curve (AUC) in peak stress was seen in Se by ROC curve analysis (AUC = 0.740, with sensitivity 67% and specificity 83%). CONCLUSION: Parameters derived from TDI offer reliable and accurate information on ischemic myocardium during adenosine stress echocardiography.

Characterization of the inflammatory cells in ascending thoracic aortic aneurysms in patients with Marfan syndrome, familial thoracic aortic aneurysms, and sporadic aneurysms.

OBJECTIVE: This study sought to characterize the inflammatory infiltrate in ascending thoracic aortic aneurysm in patients with Marfan syndrome, familial thoracic aortic aneurysm, or nonfamilial thoracic aortic aneurysm. BACKGROUND: Thoracic aortic aneurysms are associated with a pathologic lesion termed "medial degeneration," which is described as a noninflammatory lesion. Thoracic aortic aneurysms are a complication of Marfan syndrome and can be inherited in an autosomal dominant manner of familial thoracic aortic aneurysm. METHODS: Full aortic segments were collected from patients undergoing elective repair with Marfan syndrome (n = 5), familial thoracic aortic aneurysm (n = 6), and thoracic aortic aneurysms (n = 9), along with control aortas (n = 5). Immunohistochemistry staining was performed using antibodies directed against markers of lymphocytes and macrophages. Real-time polymerase chain reaction analysis was performed to quantify the expression level of the T-cell receptor beta-chain variable region gene. RESULTS: Immunohistochemistry of thoracic aortic aneurysm aortas demonstrated that the media and adventitia from Marfan syndrome, familial thoracic aortic aneurysm, and sporadic cases had increased numbers of T lymphocytes and macrophages when compared with control aortas. The number of T cells and macrophages in the aortic media of the aneurysm correlated inversely with the patient's age at the time of prophylactic surgical repair of the aorta. T-cell receptor profiling indicated a similar clonal nature of the T cells in the aortic wall in a majority of aneurysms, whether the patient had Marfan syndrome, familial thoracic aortic aneurysm, or sporadic disease. CONCLUSION: These results indicate that the infiltration of inflammatory cells contributes to the pathogenesis of thoracic aortic aneurysms. Superantigen-driven stimulation of T lymphocytes in the aortic tissues of patients with thoracic aortic aneurysms may contribute to the initial immune response.

Pathogenesis of thoracic and abdominal aortic aneurysms.

The major disease processes affecting the aorta are aortic aneurysms and dissections. Aneurysms are usually described in terms of their anatomic location, with thoracic aortic aneurysms (TAAs) involving the ascending and descending aorta in the thoracic cavity and abdominal aortic aneurysms (AAAs) involving the infrarenal abdominal aorta. Both thoracic and abdominal aortas are elastic arteries, and share similarities in their physical structures and cellular components. However, thoracic and abdominal aortas differ in their biochemical properties and the origin of their vascular smooth muscle cells (VSMCs). These similarities and differences between thoracic and abdominal aortas provide the basis for the various pathologic mechanisms observed in this disease. This review focuses on the comparison of the pathologic mechanisms involved in TAA and AAA.

Characterization of the inflammatory and apoptotic cells in the aortas of patients with ascending thoracic aortic aneurysms and dissections.

OBJECTIVE: The histopathologic abnormality underlying ascending aortic aneurysm and dissection is medial degeneration, a lesion that is described as the noninflammatory loss of smooth muscle cells and elastic fibers. This study sought to determine whether inflammatory cells are present in medial degeneration and assess any possible contribution of these cells to apoptosis of smooth muscle cells. METHODS: Aortic specimens were obtained from patients undergoing prophylactic surgical repair of an ascending aortic aneurysm (n = 9) and type A dissection (n = 7), along with control patients dying of causes unrelated to aortic disease (n = 5). Immunohistochemical staining was performed to evaluate the presence of lymphocytes and macrophages, and markers of apoptosis were assessed in the aortas of patients with ascending aortic aneurysm and dissection. RESULTS: Immunohistochemical study indicated significantly more CD3+ cells in the aortas of patients with aneurysms or dissections than in control aortas (P = .020 and P = .0022, respectively). In addition, aortas of patients with aneurysms or dissections had more CD68+ cells (P = .01 and P = .005, respectively). CD3+ cells were localized in the media and surrounding the vasa vasorum in the adventitia. Cells yielding a positive result on in situ terminal transferase-mediated deoxyuridine triphosphate nick end-labeling were found in increased numbers in the aortas of patients with aneurysms or dissections relative to control aortas (P = .005 and P = .002, respectively). Furthermore, Fas and FasL were increased in the aortic samples from patients with aneurysms and dissections relative to control aortas. CONCLUSION: The coexistence of inflammatory cells with markers of apoptotic vascular cell death in the media of ascending aortas with aneurysms and type A dissections raises the possibility that activated T cells and macrophages may contribute to the elimination of smooth muscle cells and degradation of the matrix associated with thoracic aortic aneurysms and dissections.

Mesenchymal stem cells differentiate into an endothelial phenotype, enhance vascular density, and improve heart function in a canine chronic ischemia model.

BACKGROUND: Bone marrow-derived stem cells are under investigation as a treatment for ischemic heart disease. Mesenchymal stem cells (MSCs) have been used preferentially in the acute ischemia model; data in the chronic ischemia model are lacking. METHODS AND RESULTS: Twelve dogs underwent ameroid constrictor placement. Thirty days later, they received intramyocardial injections of either MSCs (100x10(6) MSCs/10 mL saline) (n=6) or saline only (10 mL) (controls) (n=6). All were euthanized at 60 days. Resting and stress 2D echocardiography was performed at 30 and 60 days after ameroid placement. White blood cell count (WBC), C-reactive protein (CRP), creatine kinase MB (CK-MB), and troponin I levels were measured. Histopathological and immunohistochemical analyses were performed. Mean left ventricular ejection fraction was similar in both groups at baseline but significantly higher in treated dogs at 60 days. WBC and CRP levels were similar over time in both groups. CK-MB and troponin I increased from baseline to 48 hours, eventually returning to baseline. There was a trend toward reduced fibrosis and greater vascular density in the treated group. MSCs colocalized with endothelial and smooth muscle cells but not with myocytes. CONCLUSIONS: In a canine chronic ischemia model, MSCs differentiated into smooth muscle cells and endothelial cells, resulting in increased vascularity and improved cardiac function.

High throughput detection of small genomic insertions or deletions by Pyrosequencing.

Small insertions or deletions of nucleotides are common polymorphic variations in the human genome and can result in a predisposition to disease. However, high throughput methods for detecting these variations are limited. This report describes a method to detect this variation based on sequencing the boundaries of nucleotide alterations using the Pyrosequencing technique. This method can optimally detect up to 100 base pair nucleotide insertions and deletions, and also complicated genomic rearrangements.

Genetic susceptibility to enteroaggregative Escherichia coli diarrhea: polymorphism in the interleukin-8 promotor region.

Enteroaggregative Escherichia coli (EAEC) infection can be identified in 26% of travelers with diarrhea and is associated with fecal interleukin (IL)-8 production. We hypothesized that single-nucleotide polymorphisms (SNPs) in the IL-8 gene are associated with EAEC-related symptoms. Fecal IL-8 production and IL-8 SNPs at 5 loci were identified in 69 US students who remained in Mexico for 5 weeks; 23 subjects had EAEC-associated diarrhea, 7 were asymptomatic EAEC carriers, 22 had nonspecific diarrhea, and 17 were asymptomatic without an enteropathogen. The chances of having EAEC-associated diarrhea were significantly increased among those with the AA genotype at the -251 position (odds ratio [OR], 208.51; 95% confidence interval [CI], 28.5-1525.36) and among those with AT genotype (OR, 14.3; 95% CI, 1.98-105.74), compared with those with the TT genotype at the -251 position. Among subjects with EAEC-associated diarrhea, the AA genotype at the -251 position produced greater concentrations of fecal IL-8 than those with the AT or TT genotype (P=.0053). In the present study, the AA genotype at the -251 position was associated with the occurrence of EAEC-associated diarrhea and increased levels of fecal IL-8.

Mapping a locus for familial thoracic aortic aneurysms and dissections (TAAD2) to 3p24-25.

BACKGROUND: Familial thoracic aortic aneurysms and dissections (TAAD) occur as part of known syndromes such as Marfan syndrome but can also be inherited in families in an autosomal dominant manner as an isolated condition. Previous studies have mapped genes causing nonsyndromic familial TAAD to 5q13-15 (TAAD1) and 11q23.2-q24 (FAA1). Further genetic heterogeneity for the condition was evident by the presence of TAAD in some families not linked to these known loci. METHODS AND RESULTS: A 4-generation family with dominant mode of inheritance of TAAD was studied. Affected status was determined by dilation of the ascending aorta, surgical repair of an aneurysm or dissection, or death as the result of aortic dissection. None of the family members evaluated met the diagnostic criteria for Marfan syndrome. After exclusion of known loci for familial TAAD, a genome-wide scan was carried out to map the defective gene causing the disease in the family. A locus was mapped to a 25-cM region on 3p24-25 with a maximum multipoint logarithm of the odds score of 4.28. CONCLUSIONS: A third locus for nonsyndromic TAAD was mapped to 3p24-25 and termed the TAAD2 locus. This locus overlaps a previously mapped second locus for Marfan syndrome, termed the MFS2 locus. Future characterization of the TAAD2 gene will determine if TAAD2 is allelic to MFS2. In addition, identification of the TAAD2 gene will improve the presymptomatic diagnosis of individuals with this life-threatening genetic syndrome and provide information concerning the pathogenesis of the disease.