Role of Magnetic Resonance Spectroscopy in Evaluation of Cerebral Metabolic Status Before and After Carotid Endarterectomy/Thromboendarterectomy and Carotid Artery Stenting in Patients with Asymptomatic Critical Internal Carotid Artery Stenosis.

BACKGROUND The relative efficacy of carotid endarterectomy (CEA)/thromboendarterectomy (TEA) and carotid artery stenting (CAS) already has been compared in randomized controlled trials and a meta-analysis, but only limited data exist describing the status of cerebral metabolism before and after these interventions. The aim of the present study was to compare metabolic changes before and after treatment of carotid stenosis and assess their potential clinical implications.   MATERIAL AND METHODS Patients with asymptomatic unilateral critical internal CAS were imaged with proton 3T magnetic resonance spectroscopy (H-MRS) because the technique is more sensitive than regular magnetic resonance imaging for detection of the early signs of ischemic events. Abnormal metabolite ratios detected with H-MRS may precede actual morphological changes associated with hypoperfusion as well as reperfusion changes. Ipsilateral and contralateral middle cerebral artery vascular territories were both evaluated before and after vascular intervention. H-MRS was performed within 24 h before and after surgery. Correlations in the metabolic data from H-MRS for N-acetylaspartic acid (NAA)+N-acetylaspartylglutamate, creatinine (Cr)+phosphocreatinine, and phosphocholine+glycerophosphocholine (Cho) were sought. RESULTS H-MRS voxels from 11 subjects were analyzed. Values for dCho/CrI, dCho/CrC and Cho/Naal (P<0.001) were significantly higher ipsilaterally than contralaterally. Ratios for dNaa/ChoC and Cho/NaaC were significantly higher on the non-operated side (P<0.001). CONCLUSIONS H-MRS may be helpful for assessment of patients with CAS, particularly because unlike other modalities, it reveals postoperative changes in metabolic brain status. Initial results indicate the important role of perioperative neuroprotective treatment.

[Surgical treatment of internal carotid artery kinking following fibromuscular dysplasia]. / Rezul'taty khirurgicheskogo lecheniya patologicheskoi izvitosti vnutrennei sonnoi arterii na fone fibrozno-myshechnoi displazii.

OBJECTIVE: To evaluate the results of surgical treatment of internal carotid artery kinking following fibromuscular dysplasia. MATERIAL AND METHODS: There were 32 patients who underwent surgical treatment of internal carotid artery kinking following fibromuscular dysplasia. Structural changes of carotid artery wall were analyzed using immunohistochemical survey. Considering destructive changes revealed, we divided all patients into 2 groups in order to assess long-term postoperative outcomes: 1 - ICA resection followed by anastomosis in end-to-end fashion; 2 - ICA replacement. Postoperative analysis included incidence of stroke, thrombosis and deformities of anastomosis zone, regression of cerebrovascular insufficiency. RESULTS: The main «phenotype¼ of arterial wall in patients with ICA kinking following fibromuscular dysplasia is a large number of smooth muscle cells releasing matrix matelloproteinases-2 and -9 and low level of their tissue inhibitor type 1. Postoperative deformities are more common within a year after surgery. Maximum incidence is observed after 12 months. Both ICA resection and replacement are followed by similar incidence of deformity later. No severe deformities were diagnosed. Resection of ICA kinking on the background of fibromuscular dysplasia is followed by comparable results with ICA replacement regarding the incidence stroke, thrombosis and regression of cerebrovascular insufficiency. CONCLUSION: Despite degradation of extracellular matrix, destruction of elastic fibers and their fragmentation, no significant deformities are observed in long-term postoperative period in patients with ICA kinking and fibromuscular dysplasia.

Metabolic profiling of intra- and extracranial carotid artery atherosclerosis.

BACKGROUND AND AIMS: Increasing evidence shows that intracranial carotid artery atherosclerosis may develop under the influence of a differential metabolic risk factor profile than atherosclerosis in the extracranial part of the carotid artery. To further elucidate these differences, we investigated associations of a wide range of circulating metabolites with intracranial and extracranial carotid artery atherosclerosis. METHODS: From the population-based Rotterdam Study, blood samples from 1111 participants were used to determine a wide range of metabolites by proton nuclear magnetic resonance (NMR). Moreover, these participants underwent non-contrast computed tomography of the neck and head to quantify the amount of extra- and intracranial carotid artery calcification (ECAC and ICAC), as a proxy of atherosclerosis. We assessed associations of the metabolites with ICAC and ECAC and compared the metabolic association patterns of the two. RESULTS: We found that one standard deviation (SD) increase in concentration of 3-hydroxybutyrate, a ketone body, was significantly associated with a 0.11 SD increase in ICAC volume (p = 1.8 × 10-4). When we compared the metabolic association pattern of ICAC with that of ECAC, we observed differences in glycolysis-related metabolite measures, lipoprotein subfractions, and amino acids. Interestingly, glycoprotein acetyls were associated with calcification in both studied vessel beds. These associations were most prominent in men. CONCLUSIONS: We found that a higher circulating level of 3-hydroxybutyrate was associated with an increase in ICAC. Furthermore, we found differences in metabolic association patterns of ICAC and ECAC, providing further evidence for location-specific differences in the etiology of atherosclerosis.

Repeated measurements of serum concentrations of TNF-alpha, interleukin-6 and interleukin-10 in the evaluation of internal carotid artery stenosis progression.

BACKGROUND AND AIMS: The inflammatory process (with TNFα, interleukin-6 and interleukin-10 involvement) plays a key role in the development, progression and destabilization of atherosclerotic plaques. The aim of this study was to assess the importance of double-checked measurements of TNFα, interleukin-6 (IL-6) and interleukin-10 (Il-10) serum levels in patients with internal carotid artery (ICA) stenosis to determine the dynamics of changes in the stenosis degree and in the ultrasound plaque morphology. METHODS: The study included 65 patients with ICA stenosis. Ultrasound of the carotid arteries was performed during qualification and every 3 months to identify any progression of stenosis degree and dynamics of changes in plaque morphology. Serum concentrations of TNF-alpha, IL-6 and IL-10 were measured during qualification and at month 6 of the study. Calculations considered cytokine concentrations and their indices determined as relative differences of cytokine levels assessed in the first and in second tests. RESULTS: Patients with increasing degree of ICA stenosis had higher indices of IL-6 and IL-10 than patients without any increase in the stenosis degree. In patients with unfavorable dynamics of changes in plaque morphology, significantly higher levels of interleukin-6 were found in the second test; these patients had higher indices of IL-6 and IL-10 than patients with favorable dynamics of atherosclerotic plaque morphology on ultrasound. CONCLUSIONS: Long-term trends in serum concentrations of IL-6 and IL-10 in patients with ICA stenosis allow to predict the progression of the degree of stenosis and the unfavorable change of atherosclerotic plaque morphology.

[Expression of matrix metalloproteinases and their inhibitors in the internal carotid artery wall in pathological tortuosity]. / Ekspressiya matriksnykh metalloproteinaz i ikh ingibitorov v stenke vnutrennei sonnoi arterii pri patologicheskoi izvitosti.

UNLABELLED: The principal morphological sign of fibromuscular dysplasia in pathological tortuosity (PT) of the internal carotid artery (ICA) is the fragmentation of elastic fibers that are degraded by matrix metalloproteinases 2 and 9 (MMP-2, MMP-9). Nevertheless, the role of MMPs and their inhibitors in the pathogenesis of ICA PT remains completely unexplored. AIM: to investigate the expression of elastin-degrading MMPs and their inhibitors in the wall of the ICA in PT by immunohistochemistry and confocal laser scanning microscopy. METHODS: Immunohistochemical examination was made using antibodies to MMP-2, MMP-9 and their tissue inhibitors TIMP-1 and TIMP-2. MMP-9 and TIMP-1 levels were determined by confocal laser scanning microscopy. RESULTS: Immunohistochemical examination revealed a statistically significant predominance of high concentrations of MMP-2 and MMP-9 and a low level of their inhibitor TIMP-1 in ICA PT, while simultaneous obvious accumulation of both markers was most often identified in the control group (p<0.05). Analysis of MMP-2/TIMP-2 and MMP-9/TIMP-2 ratios showed the prevalence of the simultaneously high expression of both proteins in ICA PT and in the control group too. The similar data were also obtained by confocal microscopy: the control group showed elevated MMP-9 and TIMP-1 expressions and the ICA PT control displayed a high proteinase and low inhibitor levels (p<0.05). CONCLUSION: Elastic fiber fragmentation in ICA PT is due to imbalance between MMPs and their inhibitors; namely, the prevalence of MMP-2 and MMP-9 over their inhibitor TIMP-1, which leads to the degradation of extracellular matrix components, primarily elastin.

A Novel Mutation in OTX2 Causes Combined Pituitary Hormone Deficiency, Bilateral Microphthalmia, and Agenesis of the Left Internal Carotid Artery.

BACKGROUND: Mutations in OTX2 cause hypopituitarism, ranging from isolated growth hormone deficiency to combined pituitary hormone deficiency (CPHD), which are commonly detected in association with severe eye abnormalities, including anophthalmia or microphthalmia. Pituitary phenotypes of OTX2 mutation carriers are highly variable; however, ACTH deficiency during the neonatal period is not common in previous reports. OBJECTIVE: We report a novel missense OTX2 (R89P) mutation in a CPHD patient with severe hypoglycemia in the neonatal period due to ACTH deficiency, bilateral microphthalmia, and agenesis of the left internal carotid artery (ICA). RESULTS: We identified a novel heterozygous mutation in OTX2 (c.266G>C, p.R89P). R89P OTX2 showed markedly reduced transcriptional activity of HESX1 and POU1F1 reporters compared with wild-type OTX2. A dominant negative effect was noted only in the transcription analysis with POU1F1 promoter. Electrophoretic mobility shift assay experiments showed that R89P OTX2 abrogated DNA-binding ability. CONCLUSION: OTX2 mutations can cause ACTH deficiency in the neonatal period. Our study also shows that OTX2 mutations are associated with agenesis of the ICA. To the best of our knowledge, this is the first report of a transcription factor gene mutation, which was identified due to agenesis of the ICA of a patient with CPHD. This study extends our understanding of the phenotypic features, molecular mechanism, and developmental course associated with mutations in OTX2.

Investigating the Effect of a Single Infusion of Reconstituted High-Density Lipoprotein in Patients with Symptomatic Carotid Plaques.

BACKGROUND: Elevation of plasma high-density lipoprotein (HDL) cholesterol concentration reduces cardiovascular mortality and morbidity. HDLs have been shown to possess acute anti-inflammatory, antioxidant, and antithrombotic properties. We hypothesize that HDL therapy can acutely alter local and systemic manifestations of plaque instability. METHODS: Forty patients with early symptomatic carotid disease were randomized to either receive reconstituted HDL (rHDL) 40 mg/kg (n = 20) or placebo (n = 20). Carotid endarterectomies were performed 24 hr later. Plaques were obtained intraoperatively and used for measurement of thrombomodulatory genes expression. Plasma samples were collected before the infusion, 24 and 48 hr later to measure changes in systemic markers of plaque instability. RESULTS: No significant differences were noted in thrombomodulatory genes expression between the 2 groups. Systemic levels of tissue factor, matrix metalloproteinase 9 (MMP-9), and monocyte chemotactic factor-1 (MCP-1) were significantly reduced in the rHDL group. However, the effects on MMP-9 and MCP-1 were abolished in the immediate postoperative period. Although rHDL did not affect plasma interleukin-6 levels 24 hr following the infusion, it prevented the significant postoperative elevation seen in the placebo group. CONCLUSIONS: A single infusion of rHDL can acutely alter plasma biomarkers associated with plaque instability and cardiovascular morbidity.

[The structure of the internal carotid artery wall in pathological tortuosity].

OBJECTIVE: to study a change in the content of main components of the internal carotid artery (ICA) wall in pathological tortuosity (PT) resulting from fibromuscular dysplasia, using immunohistochemistry and confocal laser scanning microscopy. MATERIAL AND METHODS: Immunohistochemical (IHC) analysis using antibodies to elastin, collagen types I and III, and smooth muscle actin was made. The levels of elastin and matrix metalloproteinase 9 (MMP-9) were determined by confocal laser scanning microscopy. The relative area of expression and the area of co-location of these markers were measured. RESULTS: IHC examination of the expression of elastin revealed that the patients with PT of ICA had its higher content than the controls, but they were observed to have fiber fragmentation. Comparison of collagen types I and III expressions showed no significant differences between the groups. The found significantly lower smooth muscle actin expression in the patients with PT of ICA than in the controls was suggestive of the decreased levels of smooth muscle cells. Confocal microscopy analysis showed high elastin and low MMP-9 expressions in the control group and, on the contrary, low elastin and high proteinase levels in the PT group (р<0.05). CONCLUSION: One of the causes of PT is impairment in vascular elastic properties due to the destruction of elastic fibers and to their fragmentation, as well as to the decreased count of smooth muscle cells, which in turn causes enhanced MMP-9 activity and tissue matrix degradation.

The cytokines within the carotid plaque in symptomatic patients with internal carotid artery stenosis.

UNLABELLED: The aim of the study was the evaluation of the inflammatory cytokines within atheromatic carotid plaque. MATERIALS AND METHODS: The experiment was carried out on 100 symptomatic patients with internal carotid artery stenosis that underwent carotid endarterectomy. Every patient had the wall of the carotid artery resected during organ harvesting surgery in order to evaluate some cytokines (TGF-ß, VEGF, FGF, TNF-α) and to perform the immunohistochemistry (IHC). An immunoreactive score (IRS) was calculated based on the staining intensity and the number of cells stained. Over a 3-year period, 7 patients died, and 2 patients were lost to follow-up. The study group consisted of 91 patients. The control group comprised 20 young organ donors with confirmed death brain, who had their normal carotid artery sampled. RESULTS: In all healthy donors (control group) with normal carotid arteries the three cytokines (TGF-ß, VEGF, TNF-α) were not discovered. The presence of FGF was confirmed in 25% of healthy donors, probably due to an intima fibroblasts activity, responsible for the synthesis of elastin and collagen to the extracellular matrix (ECM). Only three cytokines (TGF-ß, FGF, TNF-α) were found within atheromatous plaques (study group). CONCLUSIONS: Our research confirmed that these factors may accelerate the development of atheromatic plaque and its destabilisation.

[The dynamics of cardio-specified marker troponin I (TN I) as a predictor of acute coronary syndrome under surgery of carotid endarterectomy].

The article deals with the data of dynamics of troponin I as a main marker of damage of myocardium under reconstructive surgery of inner carotid artery. The sampling for randomized prospective clinical examination included 227 patients. It is proved that the indicator of troponin I during the carotid endarterectomy can be used as a marker to evaluate severity of ischemic heart disease and as a predictor of possible development of acute coronary syndrome.

Internal carotid thrombus in patients with inflammatory bowel disease: two cases.

Increased ischemic stroke risk is observed in patients with inflammatory bowel disease (IBD). Causes and physiopathological aspects of cerebral infarct, in this specific population, are less often described. There is little information to provide guidelines for the best curative and preventive treatment. We report 2 cases of ischemic strokes due to internal carotid thrombus in patients during active phase of IBD. Ulceration of early atherosclerotic plaques activated by a hypercoagulation state may cause a thrombus. A combined therapy with heparin and corticosteroids was used for both our patients. Lysis of the thrombus was obtained after several days without surgical treatment and shown by ultrasonography. These cases highlight an aetiology of stroke in patients with IBD and use of a synergic treatment to respond to hypercoagulability in link with IBD. Benefits and safety of this therapy should be confirmed with clinical studies.

Pathophysiological mechanisms of carotid plaque vulnerability: impact on ischemic stroke.

Stroke is among the major causes of mortality and disabilities in the world. About 80 % of all strokes in the anterior circulation are ischemic and up to 20 % of all ischemic strokes are caused by extracranial atherosclerotic carotid artery stenosis. The prevalence of a cervical internal carotid artery stenosis increases with age and can be found in 6.9 % of the elderly population (>65 years). Atherosclerotic changes of the carotid vessel wall can lead to plaque vulnerability and may result in arterio-arterial embolism, which frequently underlie carotid-related cerebrovascular ischemic events. Carotid atherosclerosis is characterised by inflammation, extensive degradation of extracellular matrix components, neovascularization, and as recently recognised is also affected by epigenetic changes. These factors accelerate the progression of atherosclerosis towards vulnerable plaques and increase the risk of ischemic stroke. In this review, the main pathophysiological mechanisms leading to rupture-prone carotid artery plaques and successive ischemic stroke are considered. It is important to recognise the heterogeneity of atherosclerosis and that various pathophysiological processes dissected in this review are not acting individually, but rather in a complementary manner. The identification and careful integration of all relevant factors will be required for the development of future diagnostic and therapeutic strategies.

Distribution of H2S synthesis enzymes in the walls of cerebral arteries in rats.

The distribution of two enzymes involved in H(2)S synthesis, cystationine ß-synthase (CBS) and cystationine γ-liase (CSE), was studied in the walls of the internal carotid artery, order I-V branches of the middle cerebral artery basin, and intracerebral vessels of adult Wistar rats. Immunohistochemical staining showed the presence of CBS in the endothelium of small pial arteries (order IV-V branches) and intracerebral arterioles and in the capillary walls, neurons, and vascular nerves. As for CSE, in the internal carotid artery and large (order I-II) pial branches it was found mainly in the tunica media myocytes, in order III-IV vessels in myocytes and endothelium, and in smaller pial and intracerebral vessels in the endothelium. Along with enzyme-positive vessels, many pial and intracerebral arteries contained no these enzymes in the walls.

Chronic intermittent hypoxia induces local inflammation of the rat carotid body via functional upregulation of proinflammatory cytokine pathways.

Maladaptive changes in the carotid body (CB) induced by chronic intermittent hypoxia (IH) account for the pathogenesis of cardiovascular morbidity in patients with sleep-disordered breathing. We postulated that the proinflammatory cytokines, namely interleukin (IL)-1ß, IL-6 and tumor necrosis factor (TNF)-α, and cytokine receptors (IL-1r1, gp130 and TNFr1) locally expressed in the rat CB play a pathophysiological role in IH-induced CB inflammation. Results showed increased levels of oxidative stress (serum 8-isoprostane and nitrotyrosine in the CB) in rats with 7-day IH treatment resembling recurrent apneic conditions when compared with the normoxic control. Local inflammation shown by the amount of ED1-containing cells (macrophage infiltration) and the gene transcripts of NADPH oxidase subunits (gp91(phox) and p22(phox)) and chemokines (MCP-1, CCR2, MIP-1α, MIP-1ß and ICAM-1) in the CB were significantly more in the hypoxic group than in the control. In addition, the cytokines and receptors were expressed in the lobules of chemosensitive glomus cells containing tyrosine hydroxylase and the levels of expressions were significantly increased in the hypoxic group. Exogenous cytokines elevated the intracellular calcium ([Ca(2+)](i)) response to acute hypoxia in the dissociated glomus cells. The effect of cytokines on the [Ca(2+)](i) response was significantly greater in the hypoxic than in the normoxic group. Moreover, daily treatment of IH rats with anti-inflammatory drugs (dexamethasone or ibuprofen) attenuated the levels of oxidative stress, gp91(phox) expression and macrophage infiltration in the CB. Collectively, these results suggest that the upregulated expression of proinflammatory cytokine pathways could mediate the local inflammation and functional alteration of the CB under chronic IH conditions.

The activation of the cannabinoid receptor type 2 reduces neutrophilic protease-mediated vulnerability in atherosclerotic plaques.

AIMS: The activation of cannabinoid receptor type 2 (CB(2))-mediated pathways might represent a promising anti-atherosclerotic treatment. Here, we investigated the expression of the endocannabinoid system in human carotid plaques and the impact of CB(2) pharmacological activation on markers of plaque vulnerability in vivo and in vitro. METHODS AND RESULTS: The study was conducted using all available residual human carotid tissues (upstream and downstream the blood flow) from our cohort of patients symptomatic (n = 13) or asymptomatic (n = 27) for ischaemic stroke. Intraplaque levels of 2-arachidonoylglycerol, anandamide N-arachidonoylethanolamine, N-palmitoylethanolamine, N-oleoylethanolamine, and their degrading enzymes (fatty acid amide hydrolase and monoacylglycerol lipase) were not different in human plaque portions. In the majority of human samples, CB(1) (both mRNA and protein levels) was undetectable. In downstream symptomatic plaques, CB(2) protein expression was reduced when compared with asymptomatic patients. In these portions, CB(2) levels were inversely correlated (r = -0.4008, P = 0.0170) with matrix metalloprotease (MMP)-9 content and positively (r = 0.3997, P = 0.0174) with collagen. In mouse plaques, CB(2) co-localized with neutrophils and MMP-9. Treatment with the selective CB(2) agonist JWH-133 was associated with the reduction in MMP-9 content in aortic root and carotid plaques. In vitro, pre-incubation with JWH-133 reduced tumour necrosis factor (TNF)-α-mediated release of MMP-9. This effect was associated with the reduction in TNF-α-induced ERK1/2 phosphorylation in human neutrophils. CONCLUSION: Cannabinoid receptor type 2 receptor is down-regulated in unstable human carotid plaques. Since CB(2) activation prevents neutrophil release of MMP-9 in vivo and in vitro, this treatment strategy might selectively reduce carotid vulnerability in humans.

Bone marrow-derived endothelial progenitor cells participate in the initiation of moyamoya disease.

The mechanisms through which moyamoya disease occurs and progresses remain unknown. Recent studies have indicated the involvement of circulating endothelial progenitor cells (EPCs) in the development of moyamoya disease. This study directly investigated the participation of EPCs in moyamoya disease, using specimens of the supraclinoid internal carotid artery collected from two adult patients. The specimens were stained with primary antibodies against CD34, CD133, and vascular endothelial growth factor receptor-2 (VEGFR2) to localize the circulating EPCs in the thickened intima of occlusive arterial lesion. The CD34- and VEGFR2-positive cells were densely found in the thickened intima of occlusive arterial lesion, particularly clustered in the superficial layer of thickened intima. However, the number of CD34- and CD133-positive cells was very small. The CD34-positive cells also expressed von Willebrand factor on the surface of thickened intima and were also positive for α-smooth muscle actin in the deeper layer. These findings suggest that circulating EPCs may be involved in the development of occlusive arterial lesion in moyamoya disease.

Endovascular transplantation of stem cells to the injured rat CNS.

INTRODUCTION: Transplantation procedures using intraparenchymal injection of stem cells result in tissue injury in addition to associated surgical risks. Intravenous injection of mesenchymal stem cells gives engraftment to lesions, but the method has low efficiency and specificity. In traumatic brain injuries (TBI), there is a transient breakdown of the blood-brain barrier and an inflammatory response, which increase migration of cells from blood to parenchyma. The aim of this investigation was to analyze the effect of intra-arterial administration on cellular engraftment. METHODS: Experimental TBI was produced in a rat model. Endovascular technique was used to administer human mesenchymal stem cells in the ipsilateral internal carotid artery. Evaluation of engraftment and side effects were performed by immunohistochemical analysis of the brain and several other organs. The results were compared to intravenous administration of stem cells. RESULTS: Intra-arterial transplantation of mesenchymal stem cells resulted in central nervous system (CNS) engraftment without thromboembolic ischemia. We observed a significantly higher number of transplanted cells in the injured hemisphere after intra-arterial compared to intravenous administration both 1 day (p < 0.01) and 5 days (p < 0.05) after the transplantation. Some cells were also detected in the spleen but not in the other organs analyzed. CONCLUSION: Selective intra-arterial administration of mesenchymal stem cells to the injured CNS is a minimally invasive method for transplantation. The method is significantly more efficient than the intravenous route and causes no side effects in the current model. The technique can potentially be used for repeated transplantation to the CNS after TBI and in other diseases.

Ethnic differences in the relationship of carotid atherosclerosis to coronary calcification: the Multi-Ethnic Study of Atherosclerosis.

Ethnic differences in non-invasive measures of atherosclerosis are increasingly being reported, but the relationship of these measures to each other has not been widely explored. Carotid ultrasonographic and computed cardiac tomographic findings were compared in 6814 participants of White, Black, Hispanic, and Chinese ethnicities free of overt cardiovascular disease. Coronary calcium and carotid atherosclerosis were strongly related to each other in all ethnic groups. Associations of coronary calcium prevalence and common carotid intimal-medial thickness (IMT) differed by ethnicity in women, being weakest among Black women (0.07 mm IMT difference between those with and without coronary calcium) compared to the other three groups (0.10-0.12 mm difference, p=0.007). Estimated percent increments in internal carotid IMT per 10% increment in coronary calcium score were highest in Hispanics (18.5%) and lowest in Blacks (6.1%, p<0.01). Coronary calcium may be less strongly associated with carotid atherosclerosis in Blacks, particularly Black women, than in other ethnic groups. These differences should be pursued for relationships to coronary events to determine whether coronary calcium carries the same risk information in other ethnic groups as it does in Whites.

Adipophilin expression is increased in symptomatic carotid atherosclerosis: correlation with red blood cells and cholesterol crystals.

BACKGROUND AND PURPOSE: Adipophilin is an adipose differentiation-related protein expressed in lipid-containing cells. Using DNA microarray analysis, we previously found the adipophilin gene (ADFP) to be overexpressed in symptomatic carotid plaques (CP). This led us to further examine the role of adipophilin in carotid atherosclerosis relative to symptom status. METHODS: Ninety-eight high-grade (>70%) CPs were obtained in carotid endarterectomy. The relative expression of ADFP mRNA was measured by quantitative real-time RT-PCR, and the relative amount of adipophilin protein was quantified with Western blotting. Detailed topographical correlations with extravasated red blood cells and extracellular cholesterol crystals were obtained by means of immunohistochemistry. RESULTS: The relative expression of ADFP mRNA was increased in symptomatic compared with asymptomatic CPs at both the mRNA level (1.82+/-0.19[SE] versus 1.25+/-0.15, P=0.012) and the protein level (1.04+/-0.23 versus 0.46+/-0.14, P=0.043). Adipophilin colocalized with macrophage foam cells, extravasated red blood cells (P<0.0001), and cholesterol crystals (P<0.0001), and its expression associated with macroscopic ulceration of CP (P<0.0001). CONCLUSIONS: Intraplaque hemorrhages may contribute to intracellular lipid accumulation and consequent adipophilin expression. Because adipophilin blocks cholesterol efflux from lipid-laden cells, they may die and develop a necrotic lipid core, thereby destabilizing the plaque.

Taurine may prevent diabetic rats from developing cardiomyopathy also by downregulating angiotensin II type2 receptor expression.

OBJECTIVE: In diabetes, intracellular accumulation of sorbitol resulting from the high extracellular levels of glucose leads to depletion of intracellular compounds including taurine. This is associated with the development of late diabetic complications such as cardiomyopathy. The development of myocyte hypertrophy has been largely attributed to angiotensin II, whose growth properties are antagonized by taurine. However, the interaction between taurine, angiotensin II type2 receptor (AT2) and cardiomyopathy related to angiotensin II is still unknown. This study investigates the roles of taurine and AT2 in rats with streptozotocin (STZ)-induced diabetic cardiomyopathy. METHODS: Of 60 female 4-week-old Wistar rats, 8 were treated with common diet and the other 52 with high sugar/fat diet (during the whole experiment) to induce insulin resistance. At the 4th week, of the 52 rats, 7 treated with sodium citrate buffer (pH = 4.5) were grouped into control group1 (con1) and the other 45 were treated by intraperitoneal injection (I.P) with STZ to develop type 2 diabetes. At the 28th week, the maximal velocity decrease of pressure per second in left ventricle within the period of isovolumic relaxation (-dp/dt(max)) was detected by a cannula through right carotid artery. After the cannula operation, of the 45 rats, all the living 24 with -dp/dt(max)< or = 5250 mmHg/s, who had developed diabetic cardiomyopathy, were grouped as follows: 7 treated with double distilled H2O (I.P) were grouped into control group2 (con2). 8 treated with AT2 agonist (CGP42112A) (I.P) were grouped into experimental group1 (exp1). Another 9 treated with taurine (I.P) were grouped into experimental group2 (exp2). All injections lasted 4 weeks (Q.D) and the heart weight (HW) was recorded. To examine cardiomyocyte apoptosis index (CAI), mRNA and protein of AT2 and Bcl-2 in cardiomyocytes, methods of terminal-deoxynucltidyl transferase mediated nick end labeling (TUNEL), reversal transcription polymerase chain reaction (RT-PCR) and immunoblot (Western Blot) were used, respectively. RESULTS: Values of -dp/dt(max) in exp1, exp2 or con2 were much less than those in con1, respectively (p < 0.01). CAI (= stained cell number/total cell number x 100%) and AT2 values both in mRNA and protein levels in con1 were less than those in the other three groups, respectively (p < 0.01). The three parameters above were more in exp1 but less in exp2 than those in con2, respectively (p < 0.01). The three parameters and HW in exp1 were much higher than those in exp2, respectively (p < 0.01). Changes of Bcl-2 were opposed to those of AT2. CONCLUSIONS: A high expression of AT2 may accelerate the apoptosis of cardiomyocytes in diabetic rats and play a role in precipitating diabetic cardiomyopathy; taurine may protect diabetic rats from developing cardiomyopathy also by downregulating AT2 receptors.