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Yukiiri K, Hosomi N, Naya T, Takahashi T, Ohkita H, Mukai M, Masugata H, Murao K, Ueno M, Nakamura T, Dobashi H, Miki T, Kuroda Y, Kohno M. Plasma brain natriuretic peptide as a surrogate marker for cardioembolic stroke. BMC Neurol 2008; 8:45. [PMID: 19077217 PMCID: PMC2621245 DOI: 10.1186/1471-2377-8-45] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2008] [Accepted: 12/11/2008] [Indexed: 02/03/2023] Open
Abstract
Background Cardioembolic stroke generally results in more severe disability, since it typically has a larger ischemic area than the other types of ischemic stroke. However, it is difficult to differentiate cardioembolic stroke from non-cardioembolic stroke (atherothrombotic stroke and lacunar stroke). In this study, we evaluated the levels of plasma brain natriuretic peptide in acute ischemic stroke patients with cardioembolic stroke or non-cardioembolic stroke, and assessed the prediction factors of plasma brain natriuretic peptide and whether we could differentiate between stroke subtypes on the basis of plasma brain natriuretic peptide concentrations in addition to patient's clinical variables. Methods Our patient cohort consisted of 131 consecutive patients with acute cerebral infarction who were admitted to Kagawa University School of Medicine Hospital from January 1, 2005 to December 31, 2007. The mean age of patients (43 females, 88 males) was 69.6 ± 10.1 years. Sixty-two patients had cardioembolic stroke; the remaining 69 patients had non-cardioembolic stroke (including atherothrombotic stroke, lacunar stroke, or the other). Clinical variables and the plasma brain natriuretic peptide were evaluated in all patients. Results Plasma brain natriuretic peptide was linearly associated with atrial fibrillation, heart failure, chronic renal failure, and left atrial diameter, independently (F4,126 = 27.6, p < 0.0001; adjusted R2 = 0.45). Furthermore, atrial fibrillation, mitral regurgitation, plasma brain natriuretic peptide (> 77 pg/ml), and left atrial diameter (> 36 mm) were statistically significant independent predictors of cardioembolic stroke in the multivariable setting (Χ2 = 127.5, p < 0.001). Conclusion It was suggested that cardioembolic stroke was strongly predicted with atrial fibrillation and plasma brain natriuretic peptide. Plasma brain natriuretic peptide can be a surrogate marker for cardioembolic stroke.
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Zhang GX, Kimura S, Murao K, Shimizu J, Matsuyoshi H, Takaki M. Role of neuronal NO synthase in regulating vascular superoxide levels and mitogen-activated protein kinase phosphorylation. Cardiovasc Res 2008; 81:389-99. [DOI: 10.1093/cvr/cvn304] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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Murao K, Imachi H, Yu X, Cao WM, Muraoka T, Dobashi H, Hosomi N, Haba R, Iwama H, Ishida T. The transcriptional factor prolactin regulatory element-binding protein mediates the gene transcription of adrenal scavenger receptor class B type I via 3',5'-cyclic adenosine 5'-monophosphate. Endocrinology 2008; 149:6103-12. [PMID: 18755803 DOI: 10.1210/en.2008-0380] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Prolactin regulatory element-binding (PREB) protein is a transcription factor that regulates prolactin promoter activity in the rat anterior pituitary. The PREB protein is not only expressed in the anterior pituitary but also in the adrenal gland. However, the role of PREB in the adrenal gland is not clearly understood. Scavenger receptor class B type I (SR-BI) is a receptor for high-density lipoprotein that mediates the cellular uptake of high-density lipoprotein-cholesteryl ester and is a major route for cholesterol delivery to the steroidogenic pathway in the adrenal gland. In the present study, we have examined the role of PREB in regulating SR-BI. SR-BI expression was found to be regulated by cAMP, which stimulated the expression of PREB in a dose-dependent manner. Conversely, overexpression of PREB using a PREB-expressing adenovirus increased the expression of the SR-BI protein in the adrenocortical cell line Y-1. In addition, PREB induced the expression of the luciferase reporter protein that was under the control of the SR-BI promoter. EMSA showed that PREB mediates its transcriptional effect by binding to the PREB-responsive cis-element of the SR-BI promoter. Finally, we used small interfering RNA to inhibit PREB expression in the Y-1 cells and demonstrated that the knockdown of PREB expression attenuated the effects of cAMP on SR-BI expression. In summary, our data showed that in the adrenal gland, PREB regulates the transcription of the SR-BI gene via cAMP.
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Hosomi N, Naya T, Ohkita H, Mukai M, Nakamura T, Ueno M, Dobashi H, Murao K, Masugata H, Miki T, Kohno M, Kobayashi S, Koziol JA. Predictors of Intracerebral Hemorrhage Severity and Its Outcome in Japanese Stroke Patients. Cerebrovasc Dis 2008; 27:67-74. [DOI: 10.1159/000172636] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2007] [Accepted: 08/04/2008] [Indexed: 11/19/2022] Open
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Hyogo T, Taki W, Negoro M, Takahashi A, Edura M, Hyodo A, Kobayashi S, Komiyama M, Kuwayama N, Matsumaru Y, Miyachi S, Murao K, Murayama Y, Nakahara I, Nemoto S, Sakai N, Satoh K, Sonobe M, Sugiu K, Terada T, Yoshimura S, Abe T, Itoh Y, Kiyosue H, Nagashima H, Nakamura M, Matsushima S. Japanese society of neuro-endovascular treatment specialist qualification system. Six years' experience and introduction of an animal model examination. Interv Neuroradiol 2008; 14:235-40. [PMID: 20557719 DOI: 10.1177/159101990801400302] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2008] [Accepted: 07/01/2008] [Indexed: 11/15/2022] Open
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Imachi H, Murao K, Cao WM, Muraoka T, Nishiuchi T, Dobashi H, Hosomi N, Iwama H, Ishida T. The prolactin regulatory element-binding regulates of the 11beta-hydroxylase gene. Biochem Biophys Res Commun 2008; 376:531-5. [PMID: 18801336 DOI: 10.1016/j.bbrc.2008.09.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Accepted: 09/06/2008] [Indexed: 11/29/2022]
Abstract
Prolactin regulatory element-binding (PREB) protein is a transcription factor not only in pituitary but also adrenal gland. Steroid 11beta-hydroxylase (CYP11B1), a member of the cytochrome p-450 superfamily, is responsible for the last step of glucocorticoid biosynthesis in the adrenal cortices of many kinds of animals. In the present study, we have examined the role of PREB in regulating CYP11B1. CYP11B1 expression was found to be regulated by cAMP, which stimulated the expression of PREB. In addition, PREB induced the expression of the luciferase reporter protein that was under the control of the CYP11B1 promoter. Electrophoretic mobility shift analysis (EMSA) showed that PREB mediates its transcriptional effect by binding to the PREB-responsive cis-element (PRCE) of the CYP11B1 promoter. The knockdown of PREB expression attenuated the effects of cAMP on CYP11B1 expression. In summary, our data showed that in the adrenal gland, PREB regulates the transcription of the CYP11B1 gene via cAMP.
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Yokoyama K, Matsuki M, Shimano H, Sumioka S, Ikenaga T, Hanabusa K, Yasuda S, Inoue H, Watanabe T, Miyashita M, Hiramatsu R, Murao K, Kondo A, Tanabe H, Kuroiwa T. Diffusion tensor imaging in chronic subdural hematoma: correlation between clinical signs and fractional anisotropy in the pyramidal tract. AJNR Am J Neuroradiol 2008; 29:1159-63. [PMID: 18356470 DOI: 10.3174/ajnr.a1001] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Diffusion tensor imaging (DTI) was introduced as a good technique to evaluate structural abnormalities in the white matter. In this study, we used DTI to examine anisotropic changes of the pyramidal tracts displaced by chronic subdural hematoma (CSDH). MATERIALS AND METHODS Twenty-six patients with unilateral CSDH underwent DTI before and after surgery. We measured fractional anisotropy (FA) values in pyramidal tracts of bilateral cerebral peduncles and calculated the ratio of the FA value on the lesion side to that on the contralateral side (FA ratio) and compared the ratios with motor weakness. Moreover, the relationships between FA ratios and clinical factors such as age, sex, midline shift, interval from trauma, and hematoma attenuation on CT were evaluated. RESULTS FA values of pyramidal tracts on the lesion side were significantly lower than those on the contralateral side (0.66 +/- 0.07 versus 0.74 +/- 0.05, P < .0001). The FA ratio was correlated to the severity of motor weakness (r(2) = 0.32, P = .002). FA ratios after surgery improved significantly compared with those before surgery (0.96 +/- 0.08 versus 0.89 +/- 0.07, P = .0004). Intervals from trauma and the midline shift were significantly associated with decreased FA ratios (P = .0008 and P = .037). CONCLUSIONS In patients with CSDH, a reversible decrease of FA in the affected pyramidal tract on DTI was correlated to motor weakness. These anisotropic changes were considered to be caused by a reversible distortion of neuron fibers and vasogenic edema due to the hematoma.
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Murao K, Imachi H, Yu X, Cao WM, Nishiuchi T, Chen K, Li J, Ahmed RAM, Wong NCW, Ishida T. Interferon alpha decreases expression of human scavenger receptor class BI, a possible HCV receptor in hepatocytes. Gut 2008; 57:664-71. [PMID: 17998316 DOI: 10.1136/gut.2006.111443] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Infection with the hepatitis C virus (HCV) causes acute hepatitis. This disease has a high probability of becoming chronic and leading to cirrhosis, but a more deadly consequence is hepatocellular carcinoma. Interferon alpha (IFN alpha)-based treatment combined with ribavirin is the major therapeutic choice available for the treatment of chronic HCV infection. AIMS The scavenger receptor class B type I (SR-BI) or its human homologue CD36 and LIMPII Analogous-1 (hSR-BI/CLA-1) has recently been shown to interact with HCV envelope glycoprotein E2, thus suggesting that it might participate in entry of the virus into host cells. This rationale underlies current interest in the potential role of IFN alpha in hSR-BI/CLA-1 expression in HepG2 cells. RESULTS It was shown that endogenous hepatocyte expression of hSR-BI/CLA-1 was suppressed by exposure to IFN alpha. Decreased hSR-BI/CLA-1 expression in IFN alpha-treated cells was due to lower transcriptional activity of the promoter. A potential pathway for the effect of IFN alpha on hSR-BI/CLA-1 promoter activity was identified when the inhibitory action of IFN was abrogated in signal transducer and activator of transcription 1 (STAT1)/STAT2 knocked-down cells. Exposure of HepG2 cells to IFN alpha elicited a rapid phosphorylation of STAT1/STAT2, a known target of IFN alpha signalling. In addition, the mutagenesis of a STAT1/STAT2 response element in the hSR-BI/CLA-1 promoter abolished the ability of IFN alpha to suppress promoter activity. CONCLUSIONS Together, these results indicate that the STAT1/STAT2 pathway participates in IFN alpha inhibition of hSR-BI/CLA-1 expression, and raise the possibility that lowering the expression of this gene may be of therapeutic value for treating HCV infections.
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Murao K, Imachi H, Muraoka T, Fujiwara M, Kushida Y, Haba R, Ishida T. Isolated follicle-stimulating hormone (FSH) deficiency without mutation of the FSHbeta gene and successful treatment with human menopausal gonadotropin. Fertil Steril 2008; 90:2012.e17-9. [PMID: 18402948 DOI: 10.1016/j.fertnstert.2008.02.145] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Revised: 02/18/2008] [Accepted: 02/21/2008] [Indexed: 10/22/2022]
Abstract
OBJECTIVE To describe the case of isolated follicle-stimulating hormone (FSH) deficiency without mutation of the FSHbeta gene. DESIGN Case report. SETTING Division of Endocrinology and Metabolism, Department of Internal Medicine, Faculty of Medicine, Kagawa University, Kagawa, Japan. PATIENT(S) A 22-year-old man referred for infertility, azoospermia, and isolated FSH deficiency. INTERVENTION(S) The patient's FSHbeta gene was sequenced. Pituitary function at baseline and after repeated GnRH administration was evaluated. Testicular biopsy was performed. The patient was treated with human menopausal gonadotropin (hMG). MAIN OUTCOME MEASURE(S) Pathologic examination revealed hypospermatogenesis with isolated FSH deficiency without mutation of the FSHbeta gene. RESULT(S) The FSH levels remained below the normal range despite repeated GnRH stimulation. Hypospermatogenesis was confirmed by testicular biopsy. After 6 months of hMG treatment, spermatogenesis was successfully induced. CONCLUSION(S) We report the case of an infertile male with isolated FSH deficiency without any evidence of mutation in the FSHbeta gene.
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Iwama H, Hori Y, Matsumoto K, Murao K, Ishida T. ReAlignerV: web-based genomic alignment tool with high specificity and robustness estimated by species-specific insertion sequences. BMC Bioinformatics 2008; 9:112. [PMID: 18294369 PMCID: PMC2267439 DOI: 10.1186/1471-2105-9-112] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Accepted: 02/22/2008] [Indexed: 11/23/2022] Open
Abstract
Background Detecting conserved noncoding sequences (CNSs) across species highlights the functional elements. Alignment procedures combined with computational prediction of transcription factor binding sites (TFBSs) can narrow down key regulatory elements. Repeat masking processes are often performed before alignment to mask insertion sequences such as transposable elements (TEs). However, recently such TEs have been reported to influence the gene regulatory network evolution. Therefore, an alignment approach that is robust to TE insertions is meaningful for finding novel conserved TFBSs in TEs. Results We constructed a web server 'ReAlignerV' for complex alignment of genomic sequences. ReAlignerV returns ladder-like schematic alignments that integrate predicted TFBSs and the location of TEs. It also provides pair-wise alignments in which the predicted TFBS sites and their names are shown alongside each sequence. Furthermore, we evaluated false positive aligned sites by focusing on the species-specific TEs (SSTEs), and found that ReAlignerV has a higher specificity and robustness to insertions for sequences having more than 20% TE content, compared to LAGAN, AVID, MAVID and BLASTZ. Conclusion ReAlignerV can be applied successfully to TE-insertion-rich sequences without prior repeat masking, and this increases the chances of finding regulatory sequences hidden in TEs, which are important sources of the regulatory network evolution. ReAlignerV can be accessed through and downloaded from .
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Matsumoto K, Murao K, Imachi H, Nishiuchi T, Cao W, Yu X, Li J, Ahmed RAM, Iwama H, Kobayashi R, Tokumitsu H, Ishida T. The role of calcium/calmodulin-dependent protein kinase cascade on MIP-1alpha gene expression of ATL cells. Exp Hematol 2008; 36:390-400. [PMID: 18249060 DOI: 10.1016/j.exphem.2007.11.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2007] [Revised: 11/24/2007] [Accepted: 11/28/2007] [Indexed: 10/22/2022]
Abstract
OBJECTIVE Adult T-cell leukemia (ATL) is a mature CD4(+) T-cell malignancy caused by infection with human T-lymphotrophic virus type-1 and is associated with a marked hypercalcemia in many patients. Recently, it has been proposed that macrophage inflammatory protein-1alpha (MIP-1alpha) is the clinical hallmark of hypercalcemia in ATL. In this study, we investigated the effect of extracellular calcium on MIP-1alpha secretion in ATL cells and the role of Ca(2+)/calmodulin (CaM)-dependent protein kinase (CaM-K) cascade in transcriptional activation of MIP-1alpha. MATERIALS AND METHODS MIP-1alpha protein levels in the culture supernatant collected from ATL cells were measured by enzyme-linked immunosorbent assay. Reporter plasmid containing the MIP-1alpha promoter was transfected to ATL cells, and the promoter activity was measured by luciferase assay. RESULTS The addition of calcium to the culture medium enhanced the secretion of MIP-1alpha from ATL cells, which was inhibited by the CaM-KK inhibitor. The transfection of CaM-KIV stimulated MIP-1alpha promoter activity, and the upstream kinase CaM-KK enhanced the stimulatory effect of CaM-KIV on the promoter activity. Mutation in the cyclic adenosine 5' monophosphate response element (CRE) within the MIP-1alpha promoter significantly reduced the effect of CaM-KIV, and CRE mutant promoter activity was not significantly enhanced by the addition of calcium to the culture medium as compared to wild-type promoter activity. CONCLUSION Hypercalcemia enhances MIP-1alpha secretion in ATL cells, and this mechanism requires the involvement of CaM-KK/CaM-KIV cascade through the CRE. These findings raise a possibility that the inhibitory effect of CaM-KK/CaM-KIV cascade may be a potential therapeutic target for ATL.
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Murao K, Yu X, Imachi H, Cao WM, Chen K, Matsumoto K, Nishiuchi T, Wong NCW, Ishida T. Hyperglycemia suppresses hepatic scavenger receptor class B type I expression. Am J Physiol Endocrinol Metab 2008; 294:E78-87. [PMID: 17957039 DOI: 10.1152/ajpendo.00023.2007] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Hyperglycemia is a major risk factor for atherosclerotic disease. Hepatic scavenger receptor class B type I (SR-BI) binds HDL particles that mediate reverse cholesterol transport and thus lowers the risk of atherosclerosis. Here we examined glucose regulation of SR-BI gene expression in both HepG2 cells and whole animals. Results showed that hepatic SR-BI mRNA, protein, and uptake of cholesterol from HDL were halved following 48 h of exposure to 22.4 vs. 5.6 mM glucose. As in the case of the cell culture model, hepatic expression of SR-BI was lower in diabetic rats than in euglycemic rats. Transcriptional activity of the human SR-BI promoter paralleled endogenous expression of the gene, and this activity was dependent upon the dose of glucose. Next, we used inhibitors of select signal transduction pathways to demonstrate that glucose suppression of SR-BI was sensitive to the p38 MAPK inhibitor. Expression of a constitutively active p38 MAPK inhibited SR-BI promoter activity in the presence or absence of glucose. A dominant-negative p38 MAPK abolished the inhibitory effect of glucose on promoter activity. Deletional analysis located a 50-bp fragment of the promoter that mediated the effects of glucose. Within this DNA fragment there were several specificity protein-1 (Sp1) binding sites, and cellular knockdown of Sp1 abrogated its suppression by glucose. Together, these results indicate that the glucose suppression of SR-B1 expression is partially mediated by the activation of the p38 MAPK-Sp1 pathway and raise the possibility that the inhibition of hepatic SR-BI expression under high-glucose conditions provides a mechanism for accelerated atherosclerosis in diabetics.
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Murao K, Imachi H, Sato M, Dobashi H, Tahara R, Haba R, Kakehi Y, Ishida T. A case of pheochromocytoma complicated with slowly progressive type 1 diabetes mellitus and chronic thyroiditis. Endocrine 2007; 32:350-3. [PMID: 18256939 DOI: 10.1007/s12020-008-9049-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 01/09/2008] [Accepted: 01/14/2008] [Indexed: 10/22/2022]
Abstract
This is a case report regarding a 45-year-old woman, who has been undergoing treatment for diabetes mellitus (DM) with chronic thyroiditis (euthyroid state). The patient was admitted to our hospital for the evaluation of a right adrenal tumor (50 x 45 mm) and episodic hypertension. She was diagnosed as having pheochromocytoma based on the increased catecholamine and metabolite concentrations and the result of iodine-131 metaiodobenzyl guanidine ((131)I-MIBG) scintigraphy. Subsequently, the right adrenal tumor was excised. Slowly, progressive type 1 DM (SPIDDM) was confirmed by seropositivity to anti-glutamic acid decarboxylase (1890 U/ml) and the clinical course. After right adrenalectomy, the elevated catecholamine and metabolite concentrations and blood pressure returned to normal, and the dosage of insulin injection was reduced. However, she still needed the insulin injection therapy to control her blood glucose level. This case exhibited an extremely rare combination of pheochromocytoma and SPIDDM with chronic thyroiditis. Although it is common for patients with pheochromocytoma to exhibit glucose intolerance, this case raises the suggestion that measuring the levels of the autoantibody for pancreatic islet cells should be considered if SPIDDM is suspected in a patient with pheochromocytoma.
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Fujiwara M, Imachi H, Murao K, Kitamura Y, Kiguchi T, Takimoto H, Onishi H, Kushida Y, Haba R, Ishida T. [Non-Hodgkin's lymphoma associated with adrenal failure]. NIHON NAIKA GAKKAI ZASSHI. THE JOURNAL OF THE JAPANESE SOCIETY OF INTERNAL MEDICINE 2007; 96:1700-2. [PMID: 17802721 DOI: 10.2169/naika.96.1700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
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Murao K, Yu X, Cao WM, Imachi H, Chen K, Muraoka T, Kitanaka N, Li J, Ahmed RAM, Matsumoto K, Nishiuchi T, Tokuda M, Ishida T. D-Psicose inhibits the expression of MCP-1 induced by high-glucose stimulation in HUVECs. Life Sci 2007; 81:592-9. [PMID: 17655880 DOI: 10.1016/j.lfs.2007.06.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2007] [Revised: 06/06/2007] [Accepted: 06/24/2007] [Indexed: 02/02/2023]
Abstract
Monocyte chemoattractant protein-1 (MCP-1) is a 76-amino-acid chemokine thought to be the major chemotactic factor for monocytes. MCP-1 is found in macrophage-rich areas of atherosclerotic lesions. Recent report indicates that MCP-1 is induced by glucose-stimulation, raising the important link between diabetes mellitus and atherosclerosis. One of the rare sugars, d-psicose (d-ribo-2-hexulose) is present in small quantities in commercial carbohydrate complexes, however the physiological functions of d-psicose have not been evaluated. In this study, we examined the effects of d-psicose on MCP-1 expression in human umbilical vein endothelial cells (HUVECs). Results showed that MCP-1 mRNA and protein were stimulated following exposure to 22.4 mM glucose. Transcriptional activity of MCP-1 promoter paralleled endogenous expression of the gene and this activity was dependent on the dose of d-glucose. d-Psicose inhibited these effects. Next we used inhibitors of selected signal transduction pathways to show that high-glucose (HG) stimulated MCP-1 promoter activity was sensitive to p38-Mitogen-Activated Protein Kinase (p38-MAPK) pathway inhibitor. As expected, a dominant-negative p38-MAPK abolished the stimulatory effect of HG on the promoter activity. To incubate the cells with HG and d-psicose reduced the activation of p38-MAPK. Together, these results indicate that the d-psicose suppression of HG induced MCP-1 expression is mediated in part by inhibition of the p38-MAPK pathway and raise the possibility that d-psicose may be of therapeutic value in the treatment of diseases such as atherosclerosis.
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Kudo T, Iihara K, Satow T, Murao K, Miyamoto S. Incidence of Ischemic Complications after Endovascular Treatment for Ruptured Dissecting Vertebral Artery Aneurysms. Comparison between Those Arising Proximal to and Distal to the Origin of the Posterior Inferior Cerebellar Artery. Interv Neuroradiol 2007; 13 Suppl 1:157-62. [PMID: 20566095 DOI: 10.1177/15910199070130s124] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Accepted: 01/15/2007] [Indexed: 11/16/2022] Open
Abstract
SUMMARY We analyzed the incidence of ischemic complications after internal trapping for ruptured VA dissecting aneurysms. Between April 2001 and August 2005, nine cases of ruptured VA dissecting aneurysms, five in women, "proximal" or distal (distal type) to the origin of the PICA, were treated by internal trapping in the acute stage after SAH. There were four cases of proximal type and five of distal type. The demographics of the patients were reviewed in the medical charts and radiological findings were evaluated by neuroradiologists. The dissected site was completely obliterated and PICA was preserved in all cases. Follow-up angiography performed five to 19 days after treatment revealed complete obliteration of the aneurysm and patency of the PICA. The incidence of perioprocedural ischemic complications for the PICA-distal type (75%) was higher than that for the PICA-proximal type (20%). Here we retrospectively analyzed and discussed the incidence and mechanisms of ischemic complications.
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Yoshida K, Murao K, Imachi H, Cao WM, Yu X, Li J, Ahmed RAM, Kitanaka N, Wong NCW, Unterman TG, Magnuson MA, Ishida T. Pancreatic glucokinase is activated by insulin-like growth factor-I. Endocrinology 2007; 148:2904-13. [PMID: 17317782 DOI: 10.1210/en.2006-1149] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Glucokinase (GK) plays a key role in the regulation of glucose use and glucose-stimulated insulin secretion in pancreatic islet cells. Gene targeting of the IGF-I receptor down-regulated pancreatic islet GK activity. That finding prompted us to examine the potential mechanism that may control GK gene activity using an islet cell line, INS-1, known to express IGF-I receptor. Exposure of these cells to IGF-I induced GK protein expression and activity of the enzyme in a dose-dependent manner. In addition, IGF-I induced activity of a reporter construct containing the GK promoter in parallel with the effect on endogenous GK mRNA levels. The stimulatory effect of IGF-I on GK promoter activity was abrogated by wortmannin and LY294002, specific inhibitors of phosphatidylinositol 3-kinase. Exposure of cells to IGF-I elicited a rapid phosphorylation of Akt and FoxO1, a known target of Akt signaling. Constitutively active Akt stimulates the activity of the GK promoter, and a dominant-negative mutant of Akt or mutagenesis of a FoxO1 response element in the GK promoter abolished the ability of IGF-I to stimulate the promoter activity. Furthermore, cell knockdown of FoxO1 with small interfering RNA disrupted the effect of IGF-I on GK expression. These results demonstrate that the phosphatidylinositol 3-kinase/Akt/FoxO1 pathway contributes to the regulation of GK gene expression in response to IGF-I stimulation.
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Yu X, Murao K, Imachi H, Cao WM, Li J, Matsumoto K, Nishiuchi T, Ahmed RAM, Wong NCW, Kosaka H, Unterman TG, Ishida T. Regulation of scavenger receptor class BI gene expression by angiotensin II in vascular endothelial cells. Hypertension 2007; 49:1378-84. [PMID: 17404186 DOI: 10.1161/hypertensionaha.106.082479] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
High-density lipoprotein mediates a normal physiological process called reverse cholesterol transport. In this process, a scavenger receptor of the B class (SR-BI)/human homologue of SR-BI, CD36, and LIMPII analogous-1 (hSR-BI/CLA-1) facilitates the cellular uptake of cholesterol from high-density lipoprotein. In endothelial cells, high-density lipoprotein activates endothelial NO synthase via hSR-BI/CLA-1. Angiotensin II (Ang II) is a powerful accelerator of atherosclerosis and modulates the expression of endothelial NO synthase. In the present study, we have examined the role of Ang II on hSR-BI/CLA-1 expression in human umbilical vein endothelial cells. Our results showed that endogenous expression of hSR-BI/CLA-1 was suppressed by exposure to Ang II in human umbilical vein endothelial cells. Administration of the Ang II type-1 receptor blocker olmesartan inhibited Ang II-induced hSR-BI/CLA-1 protein repression. In Ang II-treated cells, high-density lipoprotein had no effect on endothelial NO synthase activation. Ang II decreased transcriptional activity of the hSR-BI/CLA-1 promoter. The inhibitory effect of Ang II on hSR-BI/CLA-1 promoter activity was abrogated by wortmannin and LY294002, specific inhibitors of phosphatidylinositol 3-kinase. Exposure of human umbilical vein endothelial cells to Ang II elicited a rapid phosphorylation of Akt and FoxO1, a known target of Akt signaling. Constitutively active Akt inhibits the activity of the hSR-BI/CLA-1 promoter, and a dominant-negative mutant of Akt or mutagenesis of a FoxO1 response element in the hSR-BI/CLA-1 abolished the ability of Ang II to suppress promoter activity. Together, these results indicate that the phosphatidylinositol 3-kinase/Akt/FoxO1 pathway participates in Ang II suppression of hSR-BI/CLA-1 expression and suggests that the endothelial receptor for hSR-BI/CLA-1 is downregulated by the renin-angiotensin system.
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MESH Headings
- Androstadienes/pharmacology
- Angiotensin II/genetics
- Angiotensin II/physiology
- Cells, Cultured
- Chromones/pharmacology
- Down-Regulation
- Endothelium, Vascular/cytology
- Endothelium, Vascular/metabolism
- Forkhead Box Protein O1
- Forkhead Transcription Factors/genetics
- Forkhead Transcription Factors/physiology
- Gene Expression Regulation/physiology
- Humans
- Imidazoles/pharmacology
- Morpholines/pharmacology
- Nitric Oxide Synthase/metabolism
- Oncogene Protein v-akt/genetics
- Oncogene Protein v-akt/physiology
- Phosphatidylinositol 3-Kinases/genetics
- Phosphatidylinositol 3-Kinases/physiology
- Phosphoinositide-3 Kinase Inhibitors
- Phosphorylation/drug effects
- Promoter Regions, Genetic/genetics
- Promoter Regions, Genetic/physiology
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptor, Angiotensin, Type 1/physiology
- Renin-Angiotensin System/physiology
- Scavenger Receptors, Class B/genetics
- Scavenger Receptors, Class B/metabolism
- Tetrazoles/pharmacology
- Wortmannin
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144
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Murao K, Kubo Y, Ohtani N, Hara E, Arase S. Epigenetic abnormalities in cutaneous squamous cell carcinomas: frequent inactivation of the RB1/p16 and p53 pathways. Br J Dermatol 2007; 155:999-1005. [PMID: 17034532 DOI: 10.1111/j.1365-2133.2006.07487.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Aberrant methylation of CpG islands in the promoter regions of cancer-related genes has been demonstrated in many human tumours. However, the methylation profile of these regions in cutaneous squamous cell carcinomas (SCCs) has not been well studied. OBJECTIVES To examine epigenetic abnormalities of a wide range of cancer-related genes in SCCs. METHODS We investigated the methylation status of 11 candidate cancer-related genes (CDH1, p16(INK4a), p14(ARF), DAPK1, MGMT, RB1, RASSF1, p15(INK4b), PTEN, PRDM2 and p53) in 20 cases of SCC by methylation-specific polymerase chain reaction, and comparatively examined the protein production of E-cadherin (CDH1), p16, RB1, p14, BMI1 and cyclin A by immunohistochemical analysis. RESULTS The frequency of cancer-related gene methylation in SCCs was: CDH1 (95%), p16 (20%), p14 (15%), DAPK1 (15%), MGMT (15%), RB1 (5%), RASSF1 (5%), p15 (0%), PTEN (0%), PRDM2 (0%) and p53 (0%). Almost all cases with hypermethylation of CDH1, p16, RB1 and p14 showed no obvious production of each protein, suggesting that promoter hypermethylation of these genes contributes to the loss of protein production. The results of methylation analysis, in combination with the results of our previous mutation analysis of CDKN2A locus and p53, revealed that 70% of SCCs have alterations in the RB1/p16 or p53 pathway. CONCLUSIONS Our findings indicate that the promoter hypermethylation of cancer-related genes, especially CDH1, is frequently shown in SCCs, and dysregulation of the RB1/p16 and/or p53 pathway through either genetic or epigenetic mechanisms, except for epigenetic abnormalities of p53 itself, should contribute to the carcinogenesis of SCCs.
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145
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Ishida T, Murao K. [Ectopic insulin secretion]. NIHON RINSHO. JAPANESE JOURNAL OF CLINICAL MEDICINE 2006; Suppl 3:208-10. [PMID: 17022532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
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146
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Nagao S, Murao K, Imachi H, Cao WM, Yu X, Li J, Matsumoto K, Nishiuchi T, Ahmed RAM, Wong NCW, Ueda K, Ishida T. Platelet derived growth factor regulates ABCA1 expression in vascular smooth muscle cells. FEBS Lett 2006; 580:4371-6. [PMID: 16854413 DOI: 10.1016/j.febslet.2006.07.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2006] [Revised: 06/20/2006] [Accepted: 07/02/2006] [Indexed: 11/15/2022]
Abstract
The ATP-binding cassette transporter A1 (ABCA1) regulates lipid efflux from peripheral cells to High-density lipoprotein. The platelet-derived growth factor (PDGF) is a potent mitogen that enables vascular smooth muscle cells to participate in atherosclerosis. In this report, we showed that PDGF suppressed endogenous expression of ABCA1 in cultured vascular smooth muscle cells. Exposure of CRL-208 cells to PDGF elicited a rapid phosphorylation of a kinase downstream from PI3-K, Akt. The constitutively active form of both p110, a subunit of PI3-K, and Akt inhibited activity of the ABCA1 promoter. In conclusion, PI3-K-Akt pathways participate in PDGF-suppression of ABCA1 expression.
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147
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Ohtsuka S, Murao K, Imachi H, Cao WM, Yu X, Li J, Iwama H, Wong NCW, Bancroft C, Ishida T. Prolactin regulatory element binding protein as a potential transcriptional factor for the insulin gene in response to glucose stimulation. Diabetologia 2006; 49:1599-607. [PMID: 16752178 DOI: 10.1007/s00125-006-0255-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2005] [Accepted: 02/13/2006] [Indexed: 11/29/2022]
Abstract
AIMS/HYPOTHESIS Prolactin regulatory element binding (PREB) protein has been identified as a factor that regulates prolactin promoter activity in rat anterior pituitary. PREB is located not only in the anterior pituitary but also in pancreas; however its role in the pancreas is not known. We therefore examined the role of PREB in insulin gene expression. MATERIALS AND METHODS To analyse the effects of PREB on insulin gene transcription, we employed the luciferase reporter gene assay and electrophoretic mobility shift assay (EMSA). In cells expressing or knocked down for PREB, insulin expression and secretion were determined. RESULTS PREB was located mainly in nuclei of rat pancreatic beta cells and its cell line, INS-1. A nuclear extract of INS-1 cells contained material that was recognised by PREB antiserum. This nuclear extract also showed insulin promoter binding activity that was super-shifted by PREB antiserum in EMSA studies. In the INS-1 cells, co-expression of PREB and the insulin promoter induced activity of the latter. The addition of glucose to the cells increased PREB expression. Deletional analysis of the insulin promoter showed that A3, a glucose-responsive cis-element in the insulin promoter, mediated the transcriptional effect of PREB. In addition, synthesised PREB bound the A3 element by EMSA, while a mutant of this motif in the insulin promoter abrogated the effect of PREB. Cells expressing or knocked down for PREB exhibited increased or decreased insulin expression, respectively. CONCLUSIONS/INTERPRETATION These results demonstrate that PREB may contribute to the regulation of insulin gene transcription and insulin secretion in response to glucose stimulation.
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148
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Hayashi K, Seyama H, Yamada N, Murao K, Iihara K, Takahashi JC, Nakajima N, Sayama T, Morimoto M, Mori H, Yamamoto M, Hishikawa T, Nonaka Y, Ayabe J, Kikuchi T, Hyuga M, Ookawa M, Kudo T, Miyamoto S. The Stenting to Internal Carotid Artery Stenosis (ICS) in Petrous Portion. The Evaluation of Plaque Figures in Magnetic Resonance Image. Interv Neuroradiol 2006; 12:193-6. [PMID: 20569630 DOI: 10.1177/15910199060120s134] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2005] [Accepted: 12/15/2005] [Indexed: 11/16/2022] Open
Abstract
SUMMARY In the safety stenting, it is important to get to know the characteristics of a plaque. In petrous carotid artery stenosis, it is difficult to know the characteristics of the plaque.We paid our attention to the MPRAGE (Magnetization Prepared Rapid Acquisition with Gradient Echo) method on high resolving power MRI. By the MPRAGE method, low intensity was observed in these lesions of all cases. This result suggested that the plaque in petrous portion was a fibrous plaque. This method is useful to get to know the characteristics of a plaque in petrous portion before endovascular treatment.
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149
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Murao K, Imachi H, Cao W, Yu X, Li J, Yoshida K, Ahmed RAM, Matsumoto K, Nishiuchi T, Wong NCW, Ishida T. High-density lipoprotein is a potential growth factor for adrenocortical cells. Biochem Biophys Res Commun 2006; 344:226-32. [PMID: 16600185 DOI: 10.1016/j.bbrc.2006.03.131] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2006] [Accepted: 03/20/2006] [Indexed: 01/02/2023]
Abstract
The entry of cholesterol contained within high-density lipoprotein (HDL) into adrenocortical cells is mediated by a human homologue of SR-BI, CD36, and LIMPII Analogous-1 (CLA-1) and thus augmenting their growth. To address the role of CLA-1, we created a mutant mCLA that lacked the C-terminal tail. HDL CE selective uptake by cells carrying the mCLA-1 receptor was fully active and equivalent to those transfected with full-length CLA-1 (fCLA-1). Expression of mCLA inhibited the proliferation of an adrenocortical cell line and the incorporation of [(3)H]thymidine into the cells. This effect was sensitive to wortmannin, an inhibitor of phosphoinositide 3-kinase (PI3K). Our transcriptional studies revealed that the inhibitory action of mCLA required the transcriptional factor AP-1 and the effect of HDL on AP-1 activation was also abrogated by wortmannin. These findings raise the possibility that the inhibitors of the effects of HDL may be of therapeutic value for adrenocortical tumor.
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150
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Kudo T, Iihara K, Murao K, Hayashi K, Ayabe J, Miyamoto S. Dissecting aneurysm of the vertebral artery developed after microvascular decompression for hemifacial spasm. Interv Neuroradiol 2006; 12:145-7. [PMID: 20569620 DOI: 10.1177/15910199060120s124] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2005] [Accepted: 12/15/2005] [Indexed: 11/17/2022] Open
Abstract
SUMMARY We report a rare case of a ruptured de novo dissecting aneurysm induced by ethyl 2-cyanoacrylate. A 39-year-old woman underwent microvascular decompression for left hemifacial spasm. The offending vessel was left posterior inferior cerebellar artery (PICA). Left vertebral artery (VA) was mobilized and affixed to the dura mater with cyanoacrylate to remove pressure of PICA to the root exit zone of the facial nerve. The left VA was found to be intact at the time of the operation. One year later, the patient sufferd subarachnoid haemorrhage (SAH) caused by rupture of a newly-developed dissecting aneurysm of the left VA. Endovascular occlusion of the dissecting site was performed using Guglielmi detachable coils. We suppose mechanical injury and chemical reaction of ethyl 2-cyanoacrylate induced dissecting aneurysm.
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