Correlations between gene expression highlight a different activation of ACE/TLR4/PTGS2 signaling in symptomatic and asymptomatic plaques in atherosclerotic patients.

Inflammation has a key role and translates the effects of many known risk factors for the disease in atherosclerotic vulnerable plaques. Aiming to look into the elements that induce the development of either a vulnerable or stable atherosclerotic plaque, and considering that inflammation has a central role in the progression of lesions, we analyzed the expression of genes involved in the ACE/TLR4/PTGS2 signaling in carotid plaques of symptomatic and asymptomatic patients. Patients with internal carotid artery stenosis undergoing carotid endarterectomy at Verona University Hospital were included in this study. A total of 71 patients was considered for gene expression analysis (29 atherothrombotic stroke patients and 42 asymptomatic patients). Total RNA was extracted from the excised plaques and expression of PTGS2, ACE, TLR4, PTGER4, PTGER3, EPRAP and ACSL4 genes was analyzed by real-time PCR. The correlation between the pair of genes was studied by Spearman coefficient. From the analyzed genes, we did not observe any individual difference in gene expression but the network of co-expressed genes suggests a different activation of pathways in the two groups of plaques.

Expression of Circulating miR-17-92 Cluster and HDAC9 Gene in Atherosclerotic Patients with Unstable and Stable Carotid Plaques.

AIMS: The miR-17-92 cluster and the HDAC9 gene are involved in inflammatory, apoptotic, and angiogenic processes that are activated in the vulnerable carotid plaque. The aim of this research was to determine whether expression of one or more of the miRs of the miR-17-92 cluster and/or HDAC9 expression could represent biomarkers for patients with unstable atherosclerotic carotid plaques. MATERIALS AND METHODS: Plasma levels of miRs and HDAC9 expression in peripheral blood were analyzed by real-time PCR in patients with histologically classified stable or unstable plaques. RESULTS: No differences were observed between the two groups. DISCUSSION AND CONCLUSIONS: Levels of the miR-17-92 cluster in plasma and HDAC9 gene expression in peripheral blood cannot be considered appropriate biomarkers to identify patients with unstable plaques at risk of rupture.

HDAC9, TWIST1 and FERD3L gene expression in asymptomatic stable and unstable carotid plaques.

BACKGROUND AND OBJECTIVES: A variant located at the end of HDAC9 gene within clusters of DNAse I sensitivity zones and histone modification hotspots has been associated with large vessel stroke and could be linked to plaque instability. The aim of the study is to define if an altered expression of HDAC9, TWIST1 and FERD3L genes could be involved in plaque vulnerability. METHODS: Histological classification and gene expression analysis were performed in 6 stable and 16 unstable plaques obtained from asymptomatic patients undergoing endarterectomy. Gene expression was analysed by real-time PCR. RESULTS AND CONCLUSIONS: TWIST1 gene expression resulted higher in stable plaques (P < 0.02). HDAC9 gene expression followed a similar trend (P = 0.11). These results highlighting the significant correlation between TWIST and HDAC9 gene expression suggest that both genes may contribute to plaque stability in a coordinated way.

Cyclooxygenase 2, toll-like receptor 4 and interleukin 1ß mRNA expression in atherosclerotic plaques of type 2 diabetic patients.

OBJECTIVES AND DESIGN: Inflammation has a prominent role in the development of atherosclerosis. Type 2 diabetes could contribute to atherosclerosis development by promoting inflammation. This status might accelerate changes in intrinsic vascular wall cells and favor plaque formation. Cyclooxygenase 2 (COX-2) is highly expressed in atherosclerotic plaques. COX-2 gene expression is promoted through activation of toll-like receptor 4 (TLR4) and pro-inflammatory cytokine interleukin 1ß (IL1-ß). Aim of this study is to investigate whether expression profiles of pro-inflammatory genes such as COX-2, TLR4 and IL1-ß in atherosclerotic plaques are altered in type 2 diabetes (T2D). METHODS: Total RNA was isolated from plaques of atherosclerotic patients and expression of COX-2, TLR4, IL1-ß analyzed using real-time PCR. Histological analysis was performed on sections of the plaque to establish the degree of instability. RESULTS: Statistically significant differences in mRNA expression of COX-2 and IL1-ß were found in plaques of T2D compared with non-T2D patients. A multi-variable linear regression model suggests that COX-2 mRNA expression is affected by T2D pathology and IL1-ß mRNA expression in atherosclerotic plaques. CONCLUSIONS: Our results support the hypothesis that T2D pathology contributes in vivo to increase the inflammatory process associated with the atherosclerotic plaque formation, as shown by an increment of COX-2 and IL1-ß mRNA expression.

Polymorphism -2604G>A variants in TLR4 promoter are associated with different gene expression level in peripheral blood of atherosclerotic patients.

Toll-like receptor-4 (TLR4) is a primary receptor of the innate immune reaction and compelling evidence demonstrates its involvement in the pathogenesis of atherosclerosis and stroke. TLR4 is constitutively expressed on monocytes and endothelial cells; it is highly expressed in atherosclerotic plaques and in peripheral blood of patients after ischemic stroke. Polymorphisms in the promoter region that alter the transcriptional regulation of this gene may represent genetic risk factors involved in the predisposition to atherosclerotic disease. In this study we investigated the effect on TLR4 gene expression of three polymorphisms in the upstream regulatory region at positions -1607T>C/rs10759932, -2026A>G/rs1927914 and -2604G>A/rs10759931 in peripheral blood of atherosclerotic patients. RNA from individuals homozygous for the -2604A allele showed a lower expression of the gene when compared to patients carrying the counterparts GG+GA. Electrophoretic mobility shift assays showed differences in the electrophoretic mobility of the DNA-nuclear protein complexes formed by the G>A variants, suggesting that the two alleles differ in their binding affinity to transcriptional factors.

Treatment of type II endoleak with a transcatheter transcaval approach: results at 1-year follow-up.

PURPOSE: This study assessed the feasibility and mid-term outcomes in the treatment of type II endoleak using transcatheter transcaval embolization (TTE). METHODS: During an 8-month period, 12 patients underwent TTE. After direct transcaval puncture of the aneurysm sac, embolization was performed by injecting thrombin and placing coils. Systemic and intrasac pressures were recorded throughout the entire procedure. Computed tomography (CT) scans were performed at 24 hours, 30 days, 6 months, and 1 year after TTE to evaluate endoleaks and changes in sac diameter. Technical success was defined as the feasibility of the procedure; clinical success was defined as no evidence of leaks during the follow-up evaluation. RESULTS: TTE was feasible in 11 of 12 patients (technical success 92%). The mean systemic pressure was 117 mm Hg. The mean intrasac pressure before embolization was 75 mm Hg (range, 39 to 125 mm Hg), 16.5 mm Hg (range, 7 to 40 mm Hg) in 10 patients after embolization, and it increased in one patient. CT scans at 24 hours showed stable contrast medium inside the sac in 10 patients. Only minor complications were observed during follow-up. At the 1-year follow-up, no recurrence of leaks was noted, and sac diameter was reduced in 10 of 11 patients. As a result, TTE clinical success was obtained in 10 (83%) of 12 patients. CONCLUSION: TTE appears to be a feasible technique for the complete exclusion of type II endoleaks. Technical and clinical successes are comparable with other treatment strategies, and TTE should be considered an alternative to direct translumbar puncture of the aneurysm sac.

Use of the Parodi anti-embolism system in carotid stenting: Italian trial results.

PURPOSE: To investigate the safety and efficacy of the Parodi anti-embolism system (PAES) in establishing flow reversal in the internal carotid artery (ICA) as a means of protecting against embolic phenomena during carotid stenting. METHODS: Seven centers participated in a nonrandomized, prospective trial of carotid angioplasty and stenting under PAES protection in 30 patients (22 men; mean age 72 years, range 49-88) with 15 symptomatic (>70%) and 15 asymptomatic (>80%) stenotic ICAs. Safety was defined as achieving sufficient brain oxygenation during flow reversal as determined by level of awareness and motor control. The presence of new or enhanced neurological deficits and death were endpoints. Performance was based on angiographic evidence of successful retrograde flow. RESULTS: The PAES was positioned in all 30 patients, but technical error and access-related difficulties prevented establishment of reversed flow in 2. Among the 28 (93%) patients treated under PAES protection, 1 patient developed aphasia after flow reversal, necessitating balloon deflation between subsequent stages of the procedure. Three other adverse events included 1 case of bradycardia and 2 cases of hypotension, with dysarthria and facial paresis in one and temporary loss of consciousness in the other. All events resolved with appropriate therapy, and there was no change from baseline in the neurological status or brain scans at 24 hours. There were no strokes or neurological deficits at 30 days. CONCLUSIONS: The PAES appears to be a safe and effective means of providing protection from embolic complications during carotid stenting.

Noninvasive diagnosis of incomplete endovascular aneurysm repair: D-dimer assay to detect type I endoleaks and nonshrinking aneurysms.

PURPOSE: To test the hypothesis that D-dimer (D-D), a cross-linked fibrin degradation product of an ongoing thrombotic event, could be a marker for incomplete aneurysm exclusion after endovascular abdominal aortic aneurysm (AAA) repair. METHODS: In a multicenter study, 83 venous blood samples were collected from 74 AAA endograft patients and controls. Twenty subjects who were >6 months postimplantation and had evidence of an endoleak and/or an unmodified or increasing AAA sac diameter formed the test group. Controls were 10 nondiseased subjects >65 years old, 18 AAA surgical candidates, and 26 postoperative endograft patients with no endoleak and a shrinking aneurysm. Blood samples were analyzed for D-D through a latex turbidimetric immunoassay. The endograft patients were stratified into 5 clinical groups for analysis: no endoleak and decreasing sac diameter, no endoleak and increasing/unchanged sac diameter, type II endoleak and decreasing sac diameter, type II endoleak and increasing/unchanged sac diameter, and type I endoleak. RESULTS: Individual D-D values were highly variable, but differences among clinical groups were statistically significant (p < 0.0001). D-D values did not vary significantly between patients with stable, untreated AAAs and age-matched controls (238 +/- 180 ng/mL versus 421 +/- 400 ng/mL, p > 0.05). Median D-D values increased at 4 days postoperatively (963 ng/mL versus 382 ng/mL, p > 0.05) and did not vary thereafter if there was no endoleak and the aneurysm sac decreased. D-D mean values were higher in patients with type I endoleak (1931 +/- 924 ng/mL, p < 0.005) and those with unchanged/increasing sac diameters (1272 +/- 728 ng/mL) than in cases with decreasing diameters (median 638 +/- 238 ng/mL) despite the presence of endoleak (p < 0.0005). CONCLUSIONS: Elevated D-D may prove to be a useful marker for fixation problems after endovascular AAA repair and may help rule out type I endoleak, thus excluding patients from unnecessary invasive tests.