Changes in DNA methylation in naïve T helper cells regulate the pathophysiological state in minimal-change nephrotic syndrome.

BACKGROUND: DNA methylation plays a crucial role in regulating transcription, and changes in DNA methylation affect gene expression and disease development. Minimal change nephrotic syndrome (MCNS) has been reported to involve immunological disturbances. Since the characteristic features of the disease include recurrent relapse and sex and age preference, the disease pathogenesis may be partly related to epigenetic changes. However, little is known about these changes. METHODS: We analyzed genome-wide DNA methylation using the microarray-based integrated analysis of methylation by isoschizomers method. This method was used to evaluate methylation in monocytes (patient number; n = 6) and naïve T helper cells (n = 4) from the peripheral blood of MCNS patients both in relapse and following remission and that of healthy controls (n = 5). RESULTS: In total, 85 co-occurring genes were identified in naïve T helper cells, while 4 such genes were identified in monocytes, which were common among the 3 following comparisons for changes in DNA methylation using sample pairs: (1) relapse versus remission, (2) relapse versus controls, and (3) remission versus controls. In 82 of 85 co-occurring genes (96.5%) in naïve T helper cells, the level of DNA methylation was altered according to disease activity, but was not related to disease activity in the 4 genes detected in monocytes. CONCLUSIONS: Therefore, in 82 co-occurring genes in naïve T helper cells, the regulation of DNA methylation was well correlated with the clinical and pathophysiological state. Our genome-wide approach to analyze DNA methylation provides further insight into the pathogenesis of MCNS and indicates potential prediction and diagnostic tool for the disease.

Suppression of MUC5AC expression in human bronchial epithelial cells by interferon-γ.

BACKGROUND: Excessive mucin secretion in the airway is an important feature of airway inflammatory diseases. MUC5AC expression is regulated by a variety of stimuli such as cytokines. Little is known about the role of interferon (IFN)-γ in MUC5AC expression in human bronchial epithelial cells. METHODS: Human pulmonary mucoepidermoid carcinoma cell line (NCI-H292) and normal human bronchial epithelial (NHBE) cells were used to assess the effects of IFN-γ on MUC5AC transcription. RESULTS: Transforming growth factor (TGF)-α and double-stranded RNA (polyI:C)-induced MUC5AC mRNA and protein expression was repressed by IFN-γ in a concentration-dependent manner. IFN-γ showed limited effects on TGF-α and polyI:C-induced activation of epidermal growth factor receptor (EGFR) and extracellular signal-regulated kinase (ERK). A chromatin immunoprecipitation assay indicated that Sp1 bound to its cognate sequence located on the MUC5AC promoter. The Sp1 inhibitor mithramycin A inhibited MUC5AC mRNA expression, implying a critical role for Sp1 in MUC5AC induction. Importantly, IFN-γ impeded Sp1 binding to the MUC5AC promoter. CONCLUSIONS: These results suggest that IFN-γ represses MUC5AC expression, disturbing binding of Sp1 to its target sequences.

Identification of genes associated with the astrocyte-specific gene Gfap during astrocyte differentiation.

Chromosomes and genes are non-randomly arranged within the mammalian cell nucleus, and gene clustering is of great significance in transcriptional regulation. However, the relevance of gene clustering and their expression during the differentiation of neural precursor cells (NPCs) into astrocytes remains unclear. We performed a genome-wide enhanced circular chromosomal conformation capture (e4C) to screen for genes associated with the astrocyte-specific gene glial fibrillary acidic protein (Gfap) during astrocyte differentiation. We identified 18 genes that were specifically associated with Gfap and expressed in NPC-derived astrocytes. Our results provide additional evidence for the functional significance of gene clustering in transcriptional regulation during NPC differentiation.

[Multiple mitral valve aneurysms, mycotic arterial embolism and aneurysms with infective endocarditis].

A 30-year-old woman with a more than 6-month history of fever, weight loss, general fatigue and dysesthesia of lower extremities was admitted to our hospital with a diagnosis of infective endocarditis. Blood cultures revealed Staphylococcus oralis. Echocardiography revealed severe mitral and moderate tricuspid regurgitation, as well as massive vegetations and aneurysms on the mitral valve. Computed tomography revealed an abdominal aortic aneurysm, left common and external iliac arterial aneurysms, and occlusion of the left common iliac, the deep femoral arteries and the bilateral tibioperoneal trunk. The ankle brachial pressure indices (ABI) were 0.94 (right) and 0.61 (left). She initially underwent mitral valve replacement and tricuspid annuloplasty. On postoperative day 24, the affected segments of the arteries were replaced with a woven Dacron bifurcated graft after resection of the mycotic abdominal and the iliac arterial aneurysms. We could not obtain a sufficient amount of omental pedicle to wrap the prosthesis. Her postoperative course was uneventful and mycotic arterial embolism and aneurysm did not recur.

The promoter of the oocyte-specific gene, Oog1, functions in both male and female meiotic germ cells in transgenic mice.

Oog1 is an oocyte-specific gene whose expression is turned on in mouse oocytes at embryonic day (E) 15.5, concomitant with the time when most of the female germ cells stop proliferating and enter meiotic prophase. Here, we characterize the Oog1 promoter, and show that transgenic GFP reporter expression driven by the 2.7 kb and 3.9 kb regions upstream of the Oog1 transcription start site recapitulates the intrinsic Oog1 expression pattern. In addition, the 3.9 kb upstream region exhibits stronger transcriptional activity than does the 2.7 kb region, suggesting that regulatory functions might be conserved in the additional 1.2 kb region found within the 3.9 kb promoter. Interestingly, the longer promoter (3.9 kb) also showed strong activity in male germ cells, from late pachytene spermatocytes to elongated spermatids. This is likely due to the aberrant demethylation of two CpG sites in the proximal promoter region. One was highly methylated in the tissues in which GFP expression was suppressed, and another was completely demethylated only in Oog1pro3.9 male and female germ cells. These results suggest that aberrant demethylation of the proximal promoter region induced ectopic expression in male germ cells under the control of 3.9 kb Oog1 promoter. This is the first report indicating that sex-dependent gene expression is altered according to the length and the methylation status of the promoter region. Additionally, our results show that individual CpG sites are differentially methylated and play different roles in regulating promoter activity and gene transcription.

DNA methylation changes between relapse and remission of minimal change nephrotic syndrome.

BACKGROUND: DNA methylation of gene promoters is associated with transcriptional inactivation. Changes in DNA methylation can lead to differences in gene expression levels and thereby influence disease development. We hypothesized that epigenetics underlies the pathogenesis of minimal change nephrotic syndrome (MCNS). METHODS: Genome-wide DNA methylation changes between relapse and remission in monocytes (n = 6) and naive T helper cells (Th0s) (n = 4) isolated from patients with MCNS were investigated using the microarray-based integrated analysis of methylation by isochizomers (MIAMI) method. We confirmed the MIAMI results using bisulfite-pyrosequencing analysis. Expression analysis was performed using quantitative real-time PCR. RESULTS: Three gene loci (GATA2, PBX4, and NYX) were significantly less methylated in Th0s during relapse than in remission, compared to none in monocytes. In addition, the distance distribution from the regression line of all probes in MIAMI was significantly different between monocytes and Th0s. The mRNA levels of the three genes in Th0s were not significantly different between relapse and remission. CONCLUSIONS: Our results demonstrate that the change in DNA methylation patterns from remission to relapse in MCNS occurs predominantly in Th0s rather than in monocytes and suggest that epigenetic regulation in Th0s underlies the pathogenesis of MCNS.

Estimation of central aortic systolic pressure using late systolic inflection of radial artery pulse and its application to vasodilator therapy.

BACKGROUND: Central blood pressure (BP) is a useful predictor of cardiovascular risk. Recently, a fully automated device that measures central SBP (cSBP) from radial late SBP (rSBP2) has been developed. METHOD: We measured cSBP using this device, compared it with aortic SBP (aSBP) measured with a high-fidelity pressure sensor, and evaluated the accuracy of cSBP before and after vasodilator administration. The data of 66 patients (mean age, 63.4 ±â€Š9.7 years; 49 men) who underwent cardiac catheterization were analyzed. The radial artery pulse waveform and brachial BP were measured sequentially and used to calculate cSBP. Brachial SBP and DBP were used for radial SBP (rSBP) and radial DBP to calculate the absolute value of rSBP2. The radial pulse waveform was recorded by an applanation tonometer (HEM-9000AI; Omron Healthcare Co. Ltd). A high-fidelity pressure sensor was placed in the ascending aorta, and aSBP was measured simultaneously by an invasive method. RESULTS: Significant positive correlations between directly measured aortic late SBP and cSBP or rSBP were observed (r = 0.93, 0.88, respectively). Changes in aSBP before and after vasodilator administration showed a trend toward higher correlation with changes in cSBP than with changes in rSBP (r = 0.84, 0.78, respectively). The slope of the linear regression line of aSBP with cSBP (slope: 0.94) was closer to unity than with rSBP (0.66). CONCLUSION: Noninvasive cSBP calculated with rSBP2 accorded well with aSBP measured by the invasive method. Vasodilator medication and four of five diseases did not affect this relation.

Cross-sectional characterization of all classes of antihypertensives in terms of central blood pressure in Japanese hypertensive patients.

BACKGROUND: Central blood pressure (CBP) has been reported to be superior to brachial blood pressure (BP) as a cardiovascular risk predictor in hypertensive patients; however, the effects of antihypertensives on CBP have not been fully examined. This cross-sectional hypothesis-generating study aimed to tentatively characterize all classes of antihypertensives in relation to CBP. METHODS: Calibrated tonometric radial artery pressure waveforms were recorded using an automated device in 1,727 treated hypertensive patients and 848 nonhypertensive (non-HT) participants. Radial artery late systolic BP (SBP) has been reported to reflect central SBP. The difference between late and peak SBPs (DeltaSBP2) was assessed with linear regression model-based adjustments. Separate regression models for DeltaSBP2 were constructed for both participant groups as well as specified sub-populations. RESULTS: DeltaSBP2 was 3.3 mm Hg lower in patients treated with any single-vasodilating (VD) antihypertensive agent without significant interclass difference than with non-VD agents, and was 2.0 mm Hg lower than estimated in nonhypertensive subjects. Combinations of two vasodilators were 6.6 and 2.9 mm Hg lower in DeltaSBP2 than nonvasodilator combinations and nonhypertensive subjects, respectively (P < 0.001 for all comparisons). Nonvasodilators and their combination showed high DeltaSBP2, 1.1 and 3.7 mm Hg higher than in nonhypertensive subjects (P < 0.001 for both). Additional adjustment of the pulse rate reduced high DeltaSBP2 with beta-blockers (betaBLs). CONCLUSIONS: This cross-sectional observation suggests that vasodilatory antihypertensives lower CBP independently of peripheral BP levels without evident class-specific differences, whereas nonvasodilators may raise CBP.

Postpartum complete atrioventricular block due to cardiac sarcoidosis: steroid therapy without permanent pacemaker.

A 32 year-old woman with bilateral hilar lymphadenopathy suffered from syncopal attacks after her first delivery. Electrocardiograms showed complete atrioventricular block (AVB) and myocardial scintigrams demonstrated a decreased uptake in the anteroseptal area. She was diagnosed as having postpartal cardiac acceleration of sarcoidosis. Because she rejected permanent pacemaker implantation, we started steroid therapy under temporary pacing. Fortunately, the treatment was very effective. Even after tapering-off of the steroid, the AVB has never reappeared. Permanent pacemaker implantation with subsequent steroid therapy is generally recommended for complete AVB due to cardiac sarcoidosis. However, steroid therapy alone can be considered for some selected cases.

The role of intravenous coronary thrombolysis for patients with acute myocardial infarction in different treatment strategies.

OBJECTIVE: To examine acute-phase outcomes in acute myocardial infarction (AMI) according to different initial treatments. PATIENTS AND METHODS: This retrospective study involved 405 patients with AMI who had undergone coronary angiography during the acute phase. The patients were retrospectively examined by dividing into groups according to treatment received: intravenous coronary thrombolysis (IVCT) (n=83), intracoronary thrombolysis (ICT) (n=62), and percutaneous coronary intervention (PCI) (n=221). RESULTS: TIMI 3 flow at the initial angiography was higher in the IVCT group (P<0.05) at 32.5% in the IVCT group and 21.7% in the non-IVCT group. The time from onset to initiation of treatment was shorter in the IVCT group (P<0.001) at 227 min in the IVCT group, 337 min in the ICT group, and 479 min in the PCI group. The acute-phase mortality was lower in the IVCT group (P<0.05) at 2.4% in the IVCT group, 3.2% in the ICT group, and 11.8% in the PCI group. According to sub-analysis, the restenosis rate during the chronic phase after PCI did not differ with or without antecedent administration of a thrombolytic agent. CONCLUSION: IVCT as an initial treatment for AMI enabled the fastest reperfusion at TIMI > or = 2 flow, resulting in a good acute-phase outcome.

Oog1, an oocyte-specific protein, interacts with Ras and Ras-signaling proteins during early embryogenesis.

We previously identified an oocyte-specific gene, Oogenesin 1 (Oog1), that encodes 326 amino acids containing a leucine zipper structure and a leucine-rich repeat. In the present study, to identify the interacting proteins of Oog1, we performed a yeast two-hybrid screening using a GV-oocyte cDNA library and found that Ral guanine nucleotide dissociation stimulator (RalGDS) is the binding partner of Oog1. Coimmunoprecipitation assay confirmed the interaction between Oog1 and RalGDS proteins. Colocalization experiments provide the evidence that the nuclear localization of RalGDS depends on the expression of Oog1. Interestingly, RalGDS protein localized in the nucleus rather than the cytoplasm between late 1-cell and early 2-cell stages, the time when Oog1 localizes in the nucleus. We also examined the interaction between Oog1 and Ras by GST pull-down assay and revealed that Oog1 interacts with Ras in a GTP-dependent manner. These findings suggest a role of Oog1 as a Ras-binding protein.

Oogenesin is a novel mouse protein expressed in oocytes and early cleavage-stage embryos.

We describe a new gene (Oogenesin) that is expressed through oogenesis and early embryogenesis in the mouse. De novo expression starts at 15.5 dpc (days postcoitum) in the ovary, which coincides with the start of oogenesis. The isolated cDNA was 1387 base pairs (bp) in length with a single open reading frame of 326 amino acids corresponding to a predicted molecular mass of 37 kDa with no significant homology to previously reported sequences. A remarkable characteristic of the gene is the presence of a leucine zipper structure at amino acid positions 131-152 and a leucine-rich domain at positions 131-254. Northern blot analysis demonstrated that the mRNA was present only in the ovary, in which it was expressed as a single transcript of approximately 1.7 kb. In situ hybridization revealed distinct signals in the oocytes in follicles at all stages (primordial to antral follicles). Western blot analysis demonstrated that the protein is expressed from oocytes to four-cell-stage embryos and that it has a little larger size (46 kDa) than the predicted size of 37. Immunohistochemical analysis of ovary sections revealed that the protein is also expressed specifically in oocytes in follicles at all stages. Furthermore, immunostaining of preimplantation embryos revealed that the protein localizes in nuclei at the late one-cell and early two-cell stages. These results suggest that the gene has some roles in zygotic transcription of early preimplantation embryos as well as folliculogenesis and oogenesis in the mouse.