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Sleep disturbance is a common problem in general adult population. Recent evidence suggests the link between the occurrence of cardiovascular events and several sleep disturbances including sleep apnea syndrome, insomnia and periodic limb movements during sleep. Sleep duration may affect the cardiovascular outcome. Shift work also may increase the risk of ischemic heart disease. Normalization of sleep rhythm has a potential to be a therapeutic target of ischemic heart diseases, although further study is required to evaluate the preventive effect on cardiovascular events. Here we describe the current understandings regarding the roles of sleep disorders during the pathogenesis of cardiovascular events.

Flow-mediated vasodilatation of the brachial artery (FMD) is a marker which is related to endothelial nitric oxide bioavailability. Commercially available ultrasound machines equipped with online computer-assisted semi-automatic analysis software to measure FMD have recently become available in Japan. These devices enable more convenient examination, enhanced reproducibility of FMD measurement, and a shortened examination time. Using such devices, in the present multicenter prospective study we propose to: 1) establish standardized FMD values and determine the annual rates of FMD change in healthy subjects; 2) confirm the predictive value of FMD for future cardiovascular events in Japanese subjects; 3) evaluate the potential usefulness of a multimarker strategy, including measurements of FMD, pulse-wave velocity (PWV), ankle-brachial pressure index, biochemical markers, and proteomic biomarkers obtained by mass spectroscopic analysis to assess the prognosis of subjects with coronary artery disease; and 4) clarify the usefulness of FMD measurement to predict the rate of progression of carotid atherosclerosis, arterial stiffness and microalbuminuria in subjects with hypertension or diabetes mellitus. In total, we estimate that approximately 4000 Japanese subjects in 3 different study groups will eventually be enrolled in this prospective observational investigation. We anticipate that the present study will provide important evidence for the usefulness of FMD measurement in the risk stratification for cardiovascular disease.

Objective: Abnormal left ventricular (LV) geometry, especially concentric hypertrophy, is associated with cardiovascular morbidity and mortality. The aim of this study was to evaluate the impact of obstructive sleep apnea syndrome (OSAS) and the effects of nasal continuous positive airway pressure (CPAP) on the LV geometric patterns., Methods: The LV morphological parameters, including the LV mass index (LVMI) and the relative wall thickness (RWT), were evaluated using echocardiography in 37 patients with OSAS diagnosed on polysomnography and 34 control subjects. Based on the values of LVMI and RWT, the LV geometry was classified as normal, concentric remodeling, concentric hypertrophy or eccentric hypertrophy. The echocardiographic parameters were reassessed after three months of CPAP treatment., Results: Compared with the controls, the OSAS patients had a higher proportion of concentric hypertrophy patterns (54% vs. 0%, p<0.001) and a lower proportion of normal geometric patterns (5% vs. 62%, p<0.001). A univariate logistic regression analysis showed the apnea-hypopnea index, lowest oxygen saturation, hypoxemia index and body mass index to each be significantly associated with the presence of concentric hypertrophy. In a multivariate analysis of these factors, the apnea-hypopnea index was found to be a significant independent factor associated with the presence of concentric hypertrophy (odds ratio: 1.06, p=0.008). Three months of CPAP treatment resulted in significant decreases in LVMI and the proportion of cases with concentric hypertrophy (both p=0.025)., Conclusion: In our limited study population, OSAS patients were found to be associated with a high prevalence of concentric LV hypertrophy patterns that were able to be reversed with three months of CPAP treatment.

A 51-year-old woman was admitted to our hospital with heart failure due to aortic regurgitation. Examination showed severe aortic regurgitation mainly due to cleft-like deformity of the right coronary cusp and single coronary artery. Aortic valve replacement was performed, and the deformity was seen in all aortic cusps. Histological study showed elongation of the leaflets by myofibrotic and fibrotic hyperplasia without calcification and inflammation in the aortic valve. This deformity likely arose from an acquired modification of a congenitally malformed aortic valve.

A 60-year-old man was admitted to our hospital due to acute ST-segment elevation myocardial infarction. He had a history of self-expanding stent implantation in the proximal left anterior descending artery due to stable angina pectoris 7 years earlier. Emergent coronary angiography on admission showed occlusion in the distal portion of the previously stented segment, in which observation by optical coherence tomography revealed the existence of a remarkable proliferation of lipid-laden neointimal tissues with rupture and thrombus. This suggests that very late stent thrombosis in a self-expanding stent may occur through the process of atheromatous formation.

Preoperative information concerning the severity and etiology of MR is very important for selecting the most appropriate surgical strategy. Ruptured chordae tendineae (RCT) are one of the most important preoperative findings. We compared the diagnostic power of transesophageal echocardiography (TEE) and transthoracic echocardiography (TTE) to detect RCT in patients with MR. We studied 61 patients with MR (30 men, 31 women; mean age, 61 ± 12 years) who underwent mitral valve repair or replacement. Both TTE and TEE were performed before the operations, and the sensitivity and specificity of TTE and TEE to detect RCT were determined. In addition, other factors that influenced the detection of RCT by these two methods were investigated. At the time of an operation, RCT was confirmed in 39 of 61 cases. Transesophageal echocardiography had a higher sensitivity than TTE (74% versus 44%; P = 0.006) to detect RCT, although the specificity was not significantly different. In patients with a body mass index (BMI) > 22 (P = 0.023) or MR grade 4 (P = 0.026), TEE had a significantly higher diagnostic sensitivity than TTE, although there was no significant difference in patients with BMI < 22 or MR grade ≤ 3. In the lateral and medial segments of the mitral valve, TEE had a significantly higher diagnostic sensitivity to detect RCT than TTE (P = 0.0012), although there was no significant difference in the middle segments. There was no significant difference between TTE and TEE with respect to the sensitivity to detect RCT in myxomatous mitral valves. Although the sensitivity of TEE was higher than that of TTE to detect RCT, it was affected by BMI, MR grade, the RCT-presenting segments, and the etiology of MR.

A 43-year-old man was admitted to our hospital presenting with seizures and syncope. He had a history of a cold with a fever of 39°C occurring three days earlier. Electrocardiography (ECG) showed complete atrioventricular block (AV block) with a maximum pause of 32 seconds, for which temporary pacing was performed. Echocardiography showed mild hypertrophy of the left ventricle (LV) with a normal ejection fraction of 61%. Coronary angiography showed normal coronary arteries. Then, an endomyocardial biopsy was performed, the results of which indicated a diagnosis of acute myocarditis. After admission, the complete atrioventricular block disappeared together with normalization of the LV wall thickness.

A 67-year-old woman was referred to our hospital with a sudden syncopal attack. She suffered from cardiogenic shock due to left ventricular (LV) outflow stenosis with simultaneous complete atrioventricular (AV) block. An endomyocardial biopsy of the left ventricle demonstrated myocardial disarray and myocardial fibrous and edematous tissue with infiltration of mononuclear cells. Cardiac magnetic resonance imaging (cMRI) detected a damaged septal area that was likely associated with the conduction disturbance. The diagnosis was hypertrophic cardiomyopathy accompanied by acute myocarditis. Although the LV outflow stenosis was transient, the complete AV block was persistent, thus requiring permanent pacemaker implantation.

Background: Recently, we and others reported that early repolarization (J wave) is associated with idiopathic ventricular fibrillation. However, its clinical and genetic characteristics are unclear., Methods and Results: This study included 50 patients (44 men; age, 45 ± 17 years) with idiopathic ventricular fibrillation associated with early repolarization, and 250 age- and sex-matched healthy controls. All of the patients had experienced arrhythmia events, and 8 (16%) had a family history of sudden death. Ventricular fibrillation was inducible by programmed electric stimulation in 15 of 29 patients (52%). The heart rate was slower and the PR interval and QRS duration were longer in patients with idiopathic ventricular fibrillation than in controls. We identified nonsynonymous variants in SCN5A (resulting in A226D, L846R, and R367H) in 3 unrelated patients. These variants occur at residues that are highly conserved across mammals. His-ventricular interval was prolonged in all of the patients carrying an SCN5A mutation. Sodium channel blocker challenge resulted in an augmentation of early repolarization or development of ventricular fibrillation in all of 3 patients, but none was diagnosed with Brugada syndrome. In heterologous expression studies, all of the mutant channels failed to generate any currents. Immunostaining revealed a trafficking defect in A226D channels and normal trafficking in R367H and L846R channels., Conclusions: We found reductions in heart rate and cardiac conduction and loss-of-function mutations in SCN5A in patients with idiopathic ventricular fibrillation associated with early repolarization. These findings support the hypothesis that decreased sodium current enhances ventricular fibrillation susceptibility.

Background: Early repolarization pattern is a common ECG finding characterized by J-point elevation and QRS notching or slurring in the inferior and/or lateral leads, yet little is known about its incidence and long-term prognosis in Asian populations., Methods and Results: We reviewed all the ECG records of the 5976 atomic-bomb survivors who were examined at least once during our biennial health examination in Nagasaki, Japan, between July 1958 and December 2004. We defined early repolarization pattern as ≥0.1-mV elevation of the J point or ST segment, with notching or slurring in at least 2 inferior and/or lateral leads. We assessed unexpected, cardiac, and all-cause death risk by Cox analysis. We identified 1429 early repolarization pattern cases (779 incident cases) during follow-up, yielding a positive rate of 23.9% and an incidence rate of 715 per 100 000 person-years. Early repolarization pattern had an elevated risk of unexpected death (hazard ratio, 1.83; 95% confidence interval, 1.12 to 2.97; P=0.02) and a decreased risk of cardiac (hazard ratio, 0.75; 95% confidence interval, 0.60 to 0.93; P<0.01) and all-cause (hazard ratio, 0.85; 95% confidence interval, 0.78 to 0.93; P<0.01) death. In addition, both slurring and notching were related to higher risk of unexpected death (hazard ratio, 2.09; 95% confidence interval, 1.06 to 4.12; P=0.03), as was early repolarization pattern manifestation in both inferior and lateral leads (hazard ratio, 2.50; 95% confidence interval, 1.29 to 4.83; P<0.01)., Conclusions: Early repolarization pattern is associated with an elevated risk of unexpected death and a decreased risk of cardiac and all-cause death. Specific early repolarization pattern morphologies and location are associated with an adverse prognosis.

Both the physiological and pathological functions of cardiovascular organs are closely related to circadian rhythm, an endogenously driven 24-h cycle. Heart rate, blood pressure, and endothelial function show diurnal variations within a day. The onset of cardiovascular disorders such as acute coronary syndrome, atrial arrhythmia, and subarachinoid hemorrhage also exhibits diurnal oscillation. Recent progress in studying the functions and molecular mechanisms of the biological clock brought forth the idea that intrinsic circadian rhythms are tightly related to cardiovascular pathology. The center of the biological clock exists in the suprachiasmatic nucleus in the hypothalamus. In addition to this central clock, each organ has its own biological clock system, termed the peripheral clock. Each cardiovascular tissue or cell, including heart and aortic tissue, cardiomyocyte, vascular smooth muscle cell, and vascular endothelial cell also has intrinsic biological rhythm. Until recently, little was known about the roles of peripheral clocks in cardiovascular organs. However, studies using genetically engineered mice revealed their contributions during the process of disease progression. Loss of synchronization between the internal clock and external stimuli can induce cardiovascular organ damage. Discrepancy in the phases between the central and peripheral clocks also seems to contribute to progression of the disorders. Elucidation of the precise roles of biological clocks in cardiovascular organs will provide us with more profound insights into the relevance of the circadian rhythm in cardiac pathology. Moreover, identification of the modalities with which we can manipulate the phase of each peripheral clock will enable us to establish a novel chronotherapeutic approach. This time-of-day based strategy may innovate a new paradigm in the prevention and treatment of cardiovascular disorders., (Copyright © 2011 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)

Interrupted inferior vena cava (IVC) with azygos continuation is a rare congenital anomaly, and is frequently associated with other cardiovascular malformations and situs anomalies, such as left isomerism. These patients usually develop deep vein thrombosis (DVT), and asymptomatic patients above 60 years of age are very rare. Here we report a case of interrupted IVC which we diagnosed in a 72-year-old woman. She was admitted to our hospital suffering from heart failure and supraventricular tachycardia. Echocardiography detected secundum atrial septal defect (ASD). An abnormal paravertebral pleural line on the chest X-rays indicated the existence of venous anomaly. Anatomical images obtained by Multidetector Computed Tomography (MDCT) helped us to successfully perform right heart catheterization procedures through azygos continuation including blood sampling from pulmonary veins. Even in elderly patients, a careful examination of chest X-rays can indicate undiagnosed venous anomalies; thus, it is critically important before planning surgical or interventional procedures.

Hypercholesterolemia is a major risk factor for cardiovascular diseases that has been managed mostly with 3-hydroxy-3-methyl glutaryl coenzyme A reductase inhibitors (statins) that suppress de novo cholesterol synthesis in the liver. Statins also have beneficial pleiotropic effects on the atherosclerotic process that are independent of their ability to lower lipid values. However, the levels of low-density lipoprotein cholesterol (LDL-C) in most hypercholesterolemic patients at high risk for cardiovascular disease do not reach the goals proposed by guidelines even when prescribed with statins. Ezetimibe is a new lipid-lowering agent that blocks the intestinal absorption of dietary and biliary cholesterol and reduces LDL-C levels, especially when combined with statins. However, its effect on cardiovascular events remains unknown. We reviewed the effects of ezetimibe on cardiovascular diseases, in particular, vascular endothelial function, which is initially impaired during the atherogenetic process and is an important predictor of cardiovascular events. The simultaneous inhibition of cholesterol synthesis by statin and of cholesterol absorption by ezetimibe might retard the atherogenetic process. These effects are considered to be mainly mediated by lipid lowering. However, further studies should elucidate the mechanism of the anti-atherosclerotic effects induced by ezetimibe; for instance, whether or not it directly affects atherogenesis independently from its lipid-lowering effects.

Background: Although chronic kidney disease is associated with a high prevalence of cardiovascular disease, the relationship between coronary artery spasm and renal dysfunction has not been elucidated., Methods and Results: We evaluated 139 patients with chest pain at rest who had no significant organic stenosis on coronary angiograms and who underwent coronary spasm provocation tests using acetylcholine or ergonovine. The results of the provocation tests revealed that 59 patients had vasospastic angina (VSA), and that 80 did not (non-VSA). We analyzed the association between VSA and renal dysfunction using the estimated glomerular filtration rate (eGFR). The eGFR was significantly lower in the VSA group than in the non-VSA group (P = 0.013). The patients were assigned to quartiles (Q) 1, 2, 3 and 4 based on eGFR (ml·min⁻¹·1.73 m²) < 64.1, 64.1-74.7, 74.8-85.0 and ≥ 85.1, respectively, in each of which the prevalence of VSA was 57%, 53%, 34% and 26%, respectively. The prevalence of VSA was significantly higher in Q1 than in Q4 (P = 0.008). Logistic regression analysis showed that the independent factors associated with the presence of VSA were a lower eGFR (P = 0.011) and male gender (P = 0.001)., Conclusions: Lower levels of eGFR in our study population were significantly and independently associated with a high prevalence of VSA, suggesting that a lower eGFR could be a risk factor for VSA.

There is a deep relationship between impaired circadian rhythm and hypertension. However, the detailed mechanisms between the daily sleep-wake rhythm and cardiovascular disorders have not yet been elucidated. To clarify the mechanism, we examined salt-sensitive Dahl rats that were fed normal chow (n=10), high-salt chow (n=10) and high-salt chow with bisoprolol (n=10). Simultaneous electroencephalogram, electromyogram and locomotor activity were examined to analyze the sleep-wake state. We also examined heart rate, blood pressure and echocardiographic findings to verify the presence of hypertension. Hypertension with impaired ventricular contraction was observed in the rats with high-salt-chow consumption whereas normal-chow rats did not show these disorders. Although rats with the normal diet showed a standard daily rhythm with normal rapid eye movement (REM) sleep duration and locomotor activity, the high-salt-diet group exhibited an impaired daily rhythm with suppressed REM sleep and significant abnormal locomotor activity. Bisoprolol significantly improved the daily sleep-wake rhythm and locomotor activity. We showed that an impaired daily rhythm was closely related to the development of hypertension. Regulation of sympathetic nerve alterations may have a key role in the treatment of hypertension and circadian rhythm disorder.

Cardiovascular functions such as heart rate and blood pressure show 24h variation. The incidence of cardiovascular diseases including acute myocardial infarction and arrhythmia also exhibits diurnal variation. The center of this circadian clock is located in the suprachiasmatic nucleus in the hypothalamus. However, recent findings revealed that each organ, including cardiovascular tissues, has its own internal clock, which has been termed a peripheral clock. The functional roles played by peripheral clocks have been reported recently. Since the peripheral clock is considered to play considerable roles in the processes of cardiac tissues, the identification of genes specifically regulated by this clock will provide insights into its role in the pathogenesis of cardiovascular disorders. In addition, the discovery of small compounds that modulate the peripheral clock will help to establish chronotherapeutic approaches. Understanding the biological relevance of the peripheral clock will provide novel approaches to the prevention and treatment of cardiovascular diseases., (2010 Elsevier B.V. All rights reserved.)

Cardiovascular functions, including blood pressure and vascular functions, show diurnal oscillation. Circadian variations have been clearly shown in the occurrence of cardiovascular events such as acute myocardial infarction. Circadian rhythm strongly influences human biology and pathology. The identification and characterization of mammalian clock genes revealed that they are expressed almost everywhere throughout the body in a circadian manner. In contrast to the central clock in the suprachiasmatic nucleus (SCN), the clock in each tissue or cell is designated as a peripheral clock. It is now accepted that peripheral clocks have their own roles specific to each peripheral organ by regulating the expression of clock-controlled genes (CCGs), although the oscillation mechanisms of the peripheral clock are similar to that of the SCN. However, little was known about how the peripheral clock in the vasculature contributes to the process of cardiovascular disorders. The biological clock allows each organ or cell to anticipate and prepare for changes in external stimuli. Recent evidence obtained using genetically engineered mice with disrupted circadian rhythm showed a novel function of the internal clock in the pathogenesis of endothelial dysfunction, hypertension and hemostasis. Loss of synchronization between the central and peripheral clock also contributes to the pathogenesis of cardiovascular diseases, as restoration of clock homeostasis could prevent disease progression. Identification of CCGs in each organ, as well as discovery of tools to manipulate the phase of each biological clock, will be of great help in establishing a novel chronotherapeutic approach to the prevention and treatment of cardiovascular disorders.

Although fatty liver predicts ischemic heart disease, the incidence and predictors of fatty liver need examination. The objective of this study was to determine fatty liver incidence and predictive variables. Using abdominal ultrasonography, we followed biennially through 2007 (mean follow-up, 11.6+/-4.6 years) 1635 Nagasaki atomic bomb survivors (606 men) without fatty liver at baseline (November 1990 through October 1992). We examined potential predictive variables with the Cox proportional hazard model and longitudinal trends with the Wilcoxon rank-sum test. In all, 323 (124 men) new fatty liver cases were diagnosed. The incidence was 19.9/1000 person-years (22.3 for men, 18.6 for women) and peaked in the sixth decade of life. After controlling for age, sex, and smoking and drinking habits, obesity (relative risk (RR), 2.93; 95% confidence interval (CI), 2.33-3.69, P<0.001), low high-density lipoprotein-cholesterol (RR, 1.87; 95% CI, 1.42-2.47; P<0.001), hypertriglyceridemia (RR, 2.49; 95% CI, 1.96-3.15; P<0.001), glucose intolerance (RR, 1.51; 95% CI, 1.09-2.10; P=0.013) and hypertension (RR, 1.63; 95% CI, 1.30-2.04; P<0.001) were predictive of fatty liver. In multivariate analysis including all variables, obesity (RR, 2.55; 95% CI, 1.93-3.38; P<0.001), hypertriglyceridemia (RR, 1.92; 95% CI, 1.41-2.62; P<0.001) and hypertension (RR, 1.31; 95% CI, 1.01-1.71; P=0.046) remained predictive. In fatty liver cases, body mass index and serum triglycerides, but not systolic or diastolic blood pressure, increased significantly and steadily up to the time of the diagnosis. Obesity, hypertriglyceridemia and, to a lesser extent, hypertension might serve as predictive variables for fatty liver.

Recent epidemiological studies have found that androgen deficiency is associated with a higher incidence of cardiovascular disease in men. However, little is known about the mechanism underlying the cardioprotective effects of androgens. Here we show the inhibitory effects of testosterone on vascular calcification and a critical role of androgen receptor (AR)-dependent transactivation of growth arrest-specific gene 6 (Gas6), a key regulator of inorganic phosphate (P(i))-induced calcification of vascular smooth muscle cells (VSMC). Testosterone and nonaromatizable androgen dihydrotestosterone inhibited P(i)-induced calcification of human aortic VSMC in a concentration-dependent manner. Androgen inhibited P(i)-induced VSMC apoptosis, an essential process for VSMC calcification. The effects on VSMC calcification were mediated by restoration of P(i)-induced down-regulation of Gas6 expression and a subsequent reduction of Akt phosphorylation. These effects of androgen were blocked by an AR antagonist, flutamide, but not by an estrogen receptor antagonist, ICI 182,780. We then explored the mechanistic role of the AR in Gas6 expression and found an abundant expression of AR predominantly in the nucleus of VSMC and two consensus ARE sequences in the Gas6 promoter region. Dihydrotestosterone stimulated Gas6 promoter activity, and this effect was abrogated by flutamide and by AR siRNA. Site-specific mutation revealed that the proximal ARE was essential for androgen-dependent transactivation of Gas6. Furthermore, chromatin immunoprecipitation assays demonstrated ligand-dependent binding of the AR to the proximal ARE of Gas6. These results indicate that AR signaling directly regulates Gas6 transcription, which leads to inhibition of vascular calcification, and provides a mechanistic insight into the cardioprotective action of androgens.

Hypertension in patients with chronic kidney disease (CKD) strongly associates with cardiovascular events. Among patients with CKD, reducing the accumulation of uremic toxins may protect against the development of hypertension and progression of renal damage, but there are no established therapies to accomplish this. Here, overexpression of human kidney-specific organic anion transporter SLCO4C1 in rat kidney reduced hypertension, cardiomegaly, and inflammation in the setting of renal failure. In addition, SLCO4C1 overexpression decreased plasma levels of the uremic toxins guanidino succinate, asymmetric dimethylarginine, and the newly identified trans-aconitate. We found that xenobiotic responsive element core motifs regulate SLCO4C1 transcription, and various statins, which act as inducers of nuclear aryl hydrocarbon receptors, upregulate SLCO4C1 transcription. Pravastatin, which is cardioprotective, increased the clearance of asymmetric dimethylarginine and trans-aconitate in renal failure. These data suggest that drugs that upregulate SLCO4C1 may have therapeutic potential for patients with CKD.

Adiponectin exhibits diverse protective effects against atherogenesis and antagonizes many effects of TNFalpha. Here, we investigated the effect of adiponectin and TNFalpha on vascular calcification, a critical event in the development and progression of vascular disease. In human aortic smooth muscle cells (HASMC), TNFalpha augmented inorganic phosphate (Pi)-induced calcification, whereas adiponectin significantly suppressed it and abolished the stimulatory effect of TNFalpha in a concentration-dependent manner. Similarly, adiponectin ameliorated the accelerating effect of TNFalpha on Pi-induced apoptosis, the essential process of HASMC calcification. Furthermore, these effects of TNFalpha and adiponectin were associated with AMP-activated protein kinase (AMPK)-dependent growth arrest-specific gene 6 (Gas6) expression and Akt signaling. The AMPK activator, 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR), induced phosphorylation of AMPK and significantly inhibited Pi-induced calcification in HASMC. Conversely, pharmacological inhibition of AMPK by compound C blocked both AMPK activation and the inhibitory effect of adiponectin on calcification, providing evidence that AMPK plays a regulatory role in vascular calcification. Reporter assay revealed that adiponectin restored Gas6 promoter activity decreased by TNFalpha, and the effect of adiponectin was abrogated by compound C. These results demonstrate that adiponectin antagonizes the stimulatory effect of TNFalpha on vascular calcification by restoration of the AMPK-dependent Gas6-mediated survival pathway.

Alteration in the differentiated state of smooth muscle cells (SMCs) is known to be integral to vascular development and the pathogenesis of vascular disease. However, it is still largely unknown how environmental cues translate into transcriptional control of SMC genes. We found that deltaEF1 is upregulated during SMC differentiation and selectively transactivates the promoters of SMC differentiation marker genes, SM alpha-actin and SM myosin heavy chain (SM-MHC). DeltaEF1 physically interacts with SRF and Smad3, resulting in a synergistic activation of SM alpha-actin promoter. Chromatin immunoprecipitation assays and knockdown experiments showed that deltaEF1 is involved in the control of the SMC differentiation programs induced by TGF-beta signaling. Overexpression of deltaEF1 inhibited neointima formation and promoted SMC differentiation, whereas heterozygous deltaEF1 knockout mice exhibited exaggerated neointima formation. It thus appears deltaEF1 mediates SMC differentiation via interaction with SRF and Smad3 during development and in vascular disease.

Recent studies have shown that C-reactive protein (CRP) is not just a predictor of cardiovascular events but also acts directly as a proinflammatory stimulus in vascular cells. In this report, we studied the molecular mechanisms underlying vascular cellular adhesion molecule-1 (VCAM-1) induction by CRP. CRP-induced VCAM-1 mRNA expression and this induction was inhibited by protein kinase C (PKC) inhibitors, p38 mitogen-activated protein kinase (MAPK) inhibitor, and tyrosine kinase inhibitors. In addition, parthenolide, a nuclear factor kappaB (NF-kappaB) inhibitor, abolished VCAM-1 induction. Moreover, CRP increased VCAM-1 promoter activity, indicating that CRP induces VCAM-1 mRNA expression at the transcriptional level. Mutation of NF-kappaB-binding sites resulted in a loss of induction. Finally, an electrophoretic mobility shift assay confirmed binding of the p65 subunit of NF-kappaB to kappaB-binding sites. Taken together, our findings suggest that VCAM-1 induction by CRP is mediated by PKC, p38MAPK, tyrosine kinase and the NF-kappaB-dependent signaling pathways in vascular endothelial cells.

Changes in the expression levels of several genes have been described in aortic aneurysm specimens, however, the spectrum of diverse molecular alterations remains to be elucidated. We attempted to identify key molecules that modulate the pathogenesis of aortic aneurysm, using a complimentary DNA microarray carrying approximately 13,000 human genes. Segments of thoracic aortic aneurysms (TAA) and adjacent normal thoracic aortic tissues without aneurysmal changes (NTA) were obtained from 20 patients undergoing graft surgery. RNA obtained from five pairs of TAA and NTA samples was compared to determine aneurysm-specific alterations using microarray. Further, the expression levels of several genes of interest were verified in the remaining specimens by real-time reverse transcription-polymerase chain reaction (RT-PCR). In microarray assays, several types of the matrix metalloproteinases were upregulated as reported previously. Also, 220 genes suggested to be involved in protein degradation, inflammation, apoptosis, stress response, intracellular signaling, and other processes were significantly upregulated. Many of these genes have not been previously implicated in cardiovascular disease. The real time RT-PCR independently confirmed that the expression levels of MMP-2, MMP-9, ADAMTS-1, and caspase 4 were consistently increased in TAA. The results indicate that many genes are involved in a complicated manner in the pathogenesis of TAA. Investigation of these genes will help clarify the pathogenesis of this disease, and may lead to the discovery of novel therapeutic targets.

Krüppel-like factor 5 (KLF5) is a zinc-finger transcription factor known to play a pivotal role in the pathogenesis of cardiovascular disease. Here, we show that neonatal heterozygous KLF5 knockout mice exhibit a marked deficiency in white adipose tissue development, suggesting that KLF5 is also required for adipogenesis. In 3T3-L1 preadipocytes, KLF5 expression was induced at an early stage of differentiation, and this was followed by expression of PPARgamma2. Constitutive overexpression of dominant-negative KLF5 inhibited adipocyte differentiation, whereas overexpression of wild-type KLF5 induced differentiation even without hormonal stimulation. Moreover, embryonic fibroblasts obtained from KLF5+/- mice showed much attenuated adipocyte differentiation, confirming the key role played by KLF5 in adipocyte differentiation. KLF5 expression is induced by C/EBPbeta and delta. KLF5, in turn, acts in concert with C/EBPbeta/delta to activate the PPARgamma2 promoter. This study establishes KLF5 as a key component of the transcription factor network controlling adipocyte differentiation.

Endothelial PAS domain protein-1 (EPAS1) regulates transcription of the genes encoding erythropoietin and vascular endothelial growth factor, which are important for maintaining oxygen homeostasis. We have previously shown that plasminogen activator inhibitor-1 (PAI-1) gene expression is induced by hypoxia. In this study, we sought to determine whether PAI-1 gene expression is directly regulated by EPAS1 in cancer cells because activities of proteases and their inhibitors are tightly regulated for tumor invasion. Hypoxia increased the PAI-1 mRNA levels in human adenocarcinoma A549 cells. Overexpression of EPAS1 significantly increased the PAI-1 mRNA and protein levels. Transient transfection assays revealed that EPAS1 increased PAI-1 gene transcription through a sequence containing 5'-CACGTACA-3' located at -194 (we refer to it as site HREPAI-1) and GT-box located at -78. Electrophoretic gel mobility shift assays revealed that HREPAI-1 serves as a binding site for EPAS1, and Sp1 constitutively binds to GT-box. In conclusion, PAI-1 expression is induced by EPAS1 through HREPAI-1 and through an Sp1-binding site. These results indicate that the PAI-1 gene is a direct target of EPAS1 and suggest the role of EPAS1 and Sp1 in the hypoxic response of cancer cells.

Growth factors, cell-surface receptors, adhesion molecules, and extracellular matrix proteins play critical roles in vascular pathophysiology by affecting growth, migration, differentiation, and survival of vascular cells. In a search for secreted and cell-surface molecules expressed in the cardiovascular system, by using a retrovirus-mediated signal sequence trap method, we isolated a cell-surface protein named vasorin. Vasorin is a typical type I membrane protein, containing tandem arrays of a characteristic leucine-rich repeat motif, an epidermal growth factor-like motif, and a fibronectin type III-like motif at the extracellular domain. Expression analyses demonstrated that vasorin is predominantly expressed in vascular smooth muscle cells, and that its expression is developmentally regulated. To clarify biological functions of vasorin, we searched for its binding partners and found that vasorin directly binds to transforming growth factor (TGF)-beta and attenuates TGF-beta signaling in vitro. Vasorin expression was down-regulated during vessel repair after arterial injury, and reversal of vasorin down-regulation, by using adenovirus-mediated in vivo gene transfer, significantly diminished injury-induced vascular lesion formation, at least in part, by inhibiting TGF-beta signaling in vivo. These results suggest that down-regulation of vasorin expression contributes to neointimal formation after vascular injury and that vasorin modulates cellular responses to pathological stimuli in the vessel wall. Thus, vasorin is a potential therapeutic target for vascular fibroproliferative disorders.

A 74 year-old Japanese woman, who had suffered from Lambert-Eaton myasthenic syndrome (LEMS), Sjoegren's syndrome, and discoid lupus erythematosus for 10 years and had been successfully controlled by 3,4-diaminopyridine and prednisolone, began to suffer from chest discomfort at night. Stress-induced myocardial ischemia in the left ventricular anterior septum was detected by thallium-201 scintigraphy. After diltiazem was prescribed, she began to feel systemic malaise and weakness in both thighs. She stopped taking diltiazem and the symptoms improved. Coronary angiography revealed 75% stenosis with calcification in the middle of the left anterior descending artery. After atherectomy with a lotablator and coronary stenting, diltiazem was prescribed. She felt malaise again, but continued taking diltiazem. After three months a follow-up coronary angiography showed no restenosis in the lesion and diltiazem was stopped. The weakness and malaise disappeared and her muscle strength recovered. LEMS is an autoimmune disorder of peripheral cholinergic transmission in which autoantibodies to the presynaptic P/Q-type voltage-gated calcium channels (VGCC) decrease the release of acetylcholine at the neuromuscular junction resulting in muscle weakness. P/Q-type VGCC regulates most of the neurotransmitter release and L-type VGCC regulates the remainder. L-type VGCC blockers are thought to have little effect on the neuromuscular junction. but they should be used very carefully. even in the remission stage of LEMS, because of preexisting neuromuscular blocking in transmission.