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COMT (Catechol-O-methyl transferase), an enzyme that metabolizes catechol, requires magnesium (Mg 2+ ) to maintain its activity. Low COMT activity causes insufficient 2-methoxyestradiol (2-ME), a biologically active metabolite from hydroxyestradiol, which leads to hypertensive disorders, including preeclampsia. Hypoestrogenism increases the risk of salt-sensitive hypertension (SSH). SSH and preeclampsia are risk factors for each other; however, the molecular mechanism of this interaction is unclear. We focused on the interactive effect of Mg 2+ insufficiency and genetic COMT deficiency on SSH using 2 strains of mice with genetically distinct COMT activity. In male mice, BL6 (C57BL/6J), a high-activity COMT strain, displayed unaltered blood pressure regardless of the Mg 2+ and salt levels in food; DBA (DBA/2J), a low-activity COMT strain, developed SSH under low Mg 2+ and high-salt conditions. COMT inhibition in C57BL/6J strain also induced SSH. Treatment with 2-ME ameliorated SSH in both models. The ATR1 (angiotensin II type 1 receptor)–STE20-SPAK (serine-proline alanine-rich kinase)–NCC (sodium chloride cotransporter) axis, molecules associated with sodium reabsorption in distal convoluted tubules, was activated in mice that developed SSH. In female DBA mice, ovariectomized mice displayed SSH under low Mg 2+ associated with activation of ATR1-SPAK-NCC axis; 2-ME inhibited all, whereas the blood pressure of sham mice was unaltered regardless of any intervention. Our findings revealed that Mg 2+ insufficiency exaggerated the low COMT activity and induced SSH via the ATR1-SPAK-NCC axis due to 2-ME insufficiency, suggesting a new pathophysiological role that links COMT/2-ME deficiency with hypertensive syndrome.

Aims/Introduction Tubulointerstitial fibrosis is a hallmark of diabetic nephropathy and is associated with an epithelial‐to‐mesenchymal transition (EMT) program and aberrant glycolysis. Dimeric pyruvate kinase (PK) M2 (PKM2) acts as a key protein kinase in aberrant glycolysis by promoting the accumulation of hypoxia‐inducible factor (HIF)‐1α, while tetrameric PKM2 functions as a pyruvate kinase in oxidative phosphorylation. The aim of the research is to study the effect of PKM2 tetramer activation on preventing kidney fibrosis via suppression of aberrant glycolysis and the EMT program. Materials and methods In vivo: Streptozotocin (STZ) was utilized to induce diabetes in 8‐week‐old CD‐1 mice; 4 weeks after diabetes induction, proteinuria‐induced kidney fibrosis was developed by intraperitoneal injection of bovine serum albumin (BSA: 0.3 g/30 g BW) for 14 days; The PKM2 activator TEPP‐46 was also administered orally simultaneously. In vitro: HK2 cells were co‐treated with high‐glucose media or/and TGF‐β1 and TEPP46 for 48 h, cellular protein was extracted for evaluation. Results Diabetic mice developed kidney fibrosis associated with aberrant glycolysis and EMT; BSA injection accelerated kidney fibrosis in both the control and diabetic mice; TEPP‐46 rescued the kidney fibrosis. In HK2 cells, TEPP‐46 suppressed the EMT program induced by TGF‐β1 and/or high‐glucose incubation. TEPP‐46‐induced PKM2 tetramer formation and PK activity resulted in suppression of HIF‐1α and lactate accumulation. Specific siRNA‐mediated knockdown of HIF‐1α expression diminished high glucose‐induced mesenchymal protein levels. Conclusion PKM2 activation could restore the tubular phenotype via suppression of the EMT program and aberrant glycolysis, providing an alternative target to mitigate fibrosis in diabetic kidneys., Diabetic kidney disease displayed kidney fibrosis associated with aberrant glycolysis and EMT program, these alterations were related to the increased level of dimeric‐PKM2 formation, PKM2 activation by TEPP46 rescued the kidney fibrosis by promoting PKM2 tetramer formation, and inhibiting dimeric‐PKM2 which directly interacted with HIF‐1α and promoted its transcription.

The biological influence of antidiabetic drugs on cancer cells and diabetic cancer patients has not yet been completely elucidated. We reported that a dipeptidyl peptidase (DPP)-4 inhibitor accelerates mammary cancer metastasis by inducing epithelial–mesenchymal transition (EMT) through the CXCL12/CXCR4/mTOR axis. Metformin has been shown to inhibit the mTOR signaling pathway. In this study, we investigated whether metformin mitigates breast cancer metastasis induced by a DPP-4 inhibitor via suppression of mTOR signaling. In cultured mouse mammary and human breast cancer cells, metformin suppressed DPP-4 inhibitor KR62436 (KR)-induced EMT and cell migration via suppression of the mTOR pathway associated with AMPK activation. For the in vivo study, metformin intervention was performed in an allograft 4T1 breast cancer model mouse with or without KR. We also analyzed mice transplanted with shRNA-mediated DPP-4 knockdown 4T1 cells. Treatment with metformin inhibited the lung metastasis of DPP-4–deficient 4T1 mammary tumor cells generated by either KR administration or DPP-4 knockdown. Immunostaining of primary tumors indicated that DPP-4 suppression promoted the expression of EMT-inducing transcription factor Snail through activation of the CXCR4-mediated mTOR/p70S6K pathway in an allograft breast cancer model; metformin abolished this alteration. Metformin treatment did not alter DPP-4–deficiency-induced expression of CXCL12 in either plasma or primary tumors. Our findings suggest that metformin may serve as an antimetastatic agent by mitigating the undesirable effects of DPP-4 inhibitors in patients with certain cancers. Implications: Metformin could combat the detrimental effects of DPP-4 inhibitor on breast cancer metastasis via mTOR suppression, suggesting the potential clinical relevance. Visual Overview: http://mcr.aacrjournals.org/content/molcanres/19/1/61/F1.large.jpg.

The importance of fibrinogen replacement therapy in obstetric disseminated intravascular coagulation is well recognized. However, fibrinogen measurement in conventional laboratories has been a time-consuming task. Recently, a Japanese manufacturer developed a portable device that enables immediate fibrinogen measurement at the point of care. This report describes a case in which this device was used for the successful management of obstetric disseminated intravascular coagulation.

Key Clinical Message However, the common strategy for eliminating premature ventricular contractions (PVCs) is to explore the exit site and ablate, which may be difficult in some cases. The origin and the preferential pathway, an insulated pathway connected to the exit, may also become targets for eliminating PVCs.

Cardiac involvement secondary to polymyositis is not infrequent. In addition, it sometimes presents various forms of arrhythmia, including atrial tachycardia (AT). A 72-year-old female who had 5-years history of polymyositis was referred to our clinic with symptomatic supraventricular tachycardia with 2:1 atrioventricular conduction. Electrophysiological study revealed a total of three focal AT in right atrium with the origin of the basal right atrial appendage (AT1), coronary sinus ostium (AT2), and low lateral right atrium (AT3), respectively. Endocardial bipolar voltage mapping showed low voltage area in the limited area, partially overlapping with the focus of AT3. We finally terminated AT2 targeting an early fractionated potential and AT3 at early activation site with a support of flexibly-bended deflectable sheath while accidentally eliminating AT3 with the bumping of a catheter. With the additional applications, we completely eliminated all AT. AT were never provoked by any inductions with isoproterenol infusion. .

Quantitative flow ratio (QFR) is an image-based fractional flow reserve (FFR) computed by three-dimensional quantitative coronary angiography and estimated flow velocity. Several studies have reported that QFR was rapidly computed within approximately 5 min and had a good diagnostic performance as compared with FFR. However, studies comparing QFR with instantaneous wave-free ratio (iFR) as an index with a prognostic value comparable to that of FFR are limited. Thus, we investigated the applicability of QFR with respect to iFR, both being easy-to-measure indices not requiring pharmacological hyperaemic induction. We computed QFR in prospectively enrolled 150 coronary lesions (including 50 lesions for onsite QFR analysis) in consecutive patients with intermediate stenosis evaluated by iFR. The correlation and diagnostic performance of QFR were compared using iFR as a reference. The mean QFR and iFR were 0.81 ± 0.12 and 0.89 ± 0.11, respectively. QFR and iFR exhibited a good correlation in all subjects (R = 0.70, p < 0.0001) and the onsite-analysed vessels (R = 0.74, p < 0.0001). In the receiver-operating characteristics analysis, the area under the curve of QFR predicting iFR ≤ 0.89 was 0.91. Applying the cut-off value of QFR ≤ 0.80 and iFR ≤ 0.89, the sensitivity, specificity, positive and negative predictive values were 85%, 83%, 72%, and 91%, respectively, in all subjects, and 82%, 82%, 78%, and 85%, respectively, in the onsite-analysed vessels. QFR including onsite analysis demonstrated a good correlation with iFR and a diagnostic performance comparable to that of iFR in consecutive patients with intermediate coronary stenosis, suggesting its potential as a rapidly derived index for evaluating myocardial ischaemia in clinical settings.

Aim This study aimed to investigate the rate of labor-onset hypertension (LOH) under neuraxial labor analgesia and the effect of neuraxial labor analgesia on LOH. Methods A retrospective study was conducted in a tertiary university hospital from 2015 to 2016. Patients who were admitted to the hospital for vaginal delivery under combined spinal and epidural anesthesia were selected. LOH was defined as the elevation of systolic blood pressure (BP) to ≥140 mmHg or diastolic BP to ≥90 mmHg for the first time after the onset of labor. Cases of LOH that persisted after neuraxial labor analgesia (prolonged LOH) were further analyzed to determine the hypertension severity and therapeutic intervention rate. Results Among 775 patients, 213 (28.4%) developed LOH. Prolonged LOH was observed in 30 patients (3.9%). LOH severity and the likelihood of prolonged LOH were positively correlated. Therapeutic intervention was administered only to the patients with prolonged LOH, that is, to 100% of those with emergent hypertension, to 21.1% of those with severe hypertension during labor, and to 36.8% of those with severe hypertension, to 55.6% of those with mild hypertension in the post-partum period. Conclusion The rate of LOH was reduced significantly after neuraxial labor analgesia. Patients with prolonged LOH should be carefully followed up during labor and in the post-partum period because such patients often require antihypertensive therapy.

Cardiac tumors are rare, and multiple myxomas are even rarer. The latter phenomenon is mostly associated with the Carney complex, a dominantly inherited disease characterized by multiple primary cardiac myxomas, endocrinopathy, and spotty pigmentation of the skin. We report the rare case of a patient who did not have the Carney complex but had multiple primary cardiac tumors. A 78-year-old woman with a past history of breast cancer was referred to our hospital for further examination of multiple cardiac tumors. Echocardiography showed 4 tumors in the left atrium and left ventricle. We could not diagnose them preoperatively and decided to resect them surgically because they were mobile and could have caused embolism and obstruction. The postoperative pathological findings of all 4 tumors were myxomas, although the patient did not meet the diagnostic criteria of the Carney complex. Therefore, a rare case of multiple primary cardiac myxomas was diagnosed.

Although the efficacy of catheter ablation of the accessory pathway (AP) has been established, there are subgroups of APs with an intermittent conduction property, which is sometimes difficult to diagnose accurately. A 57-year-old man with a history of catheter ablation was referred to our clinic due to frequent faintness. He had undergone concealed AP ablation 8 years previously and bilateral circumferential pulmonary vein isolation (CPVI) 6 years previously. During regular electrocardiogram monitoring, it was suggested that irregular wide QRS tachycardia, which was considered to be atrial fibrillation with antegrade AP conduction, was the cause of the present symptoms. In the present electrophysiological study, we noticed a residual antegrade AP in the left lateral wall that was not observed during the previous session. We achieved abolition of overt accessory conduction, bilateral CPVI, and superior vena cava isolation with several radiofrequency applications without any recurrence. We also confirmed the absence of dormant conduction in the AP and the left atrium-PV connection with 20 mg adenosine triphosphate. This case demonstrated the possibility of sudden exposure of overt AP conduction late after catheter ablation of the concealed AP and the importance of confirming the absence of dormant conduction by means of adenosine triphosphate, which has the potential benefit of revealing latent AP conduction.

Dipeptidyl peptidase (DPP)-4 is a multifunctional glycoprotein involved in various biological and pathologic processes. DPP-4 has been widely recognized as a therapeutic target for type 2 diabetes mellitus but is also implicated in the development of human malignancies. Here, we show that inhibition of DPP-4 accelerates breast cancer metastasis via induction of CXCL12/CXCR4, which activates mTOR to promote epithelial–mesenchymal transition (EMT). In cultured cells, DPP-4 knockdown induced EMT and cell migration. Treatment with the DPP-4 inhibitor KR62436 (KR) promoted primary tumor growth and lung metastasis in a 4T1 tumor allograft mouse model; DPP-4 knockdown in 4T1 cells displayed similar phenotypes in vivo and in vitro. KR treatment enhanced the levels of CXCL12/CXCR4 and phosphorylated mTOR, which were associated with the induction of EMT in metastatic cancer cells. KR-induced EMT in cancer cells was inhibited by treatment with the CXCR4 inhibitor AMD3100 or the mTOR inhibitor rapamycin, and AMD3100 suppressed KR-induced metastasis in vivo. Our findings suggest that DPP-4 plays a significant role in cancer biology and that inhibition of DPP-4 promotes cancer metastasis via induction of the CXCL12/CXCR4/mTOR/EMT axis. Significance: These findings reveal that inhibition of DPP-4 increases the metastatic potential of breast cancer. This is especially important given the potential use of DPP-4 inhibition as a therapeutic strategy for type 2 diabetes.

Introduction The efficacy of thoracic vein isolation (TVI), an approach to trigger atrial fibrillation (AF), for the management of AF has been established. Our goal was to identify the predictors for late recurrence of atrial tachyarrhythmias (ATAs), for which the patients and procedural and/or echocardiographic parameters were retrospectively analyzed. Although substrate modification in the atrium for the treatment of AF ablation remains controversial, the background associated with the outcome has not been fully investigated. We retrospectively studied 33 patients with paroxysmal AF and 21 with persistent AF undergoing defragmentation followed by TVI. We evaluated the late/early recurrences, defined as ATA at 3 months after/within the single procedure. Methods and Results During a median follow-up period of 22 (11-37) months, 28 patients (52%) experienced a late recurrence. There was a higher incidence of late recurrences in the patients with disease durations of ≥12.4 months, which was the optimal cut-off point measured in the receiver operating characteristic curve analysis, or in those with left atrial diameter >50 mm or with earlier recurrences than the others (19% versus 72%, p=0.01; 0% versus 37%, p=0.02; or 13% versus 53%, p

A 39-year-old woman with no coronary risk factors was admitted due to repetitive morning chest pain. Coronary angiography revealed subtotal occlusion of the distal obtuse marginal branch that was not recanalized by intracoronary nitroglycerin administration. Intravascular ultrasound and optical frequency domain imaging showed tandem intramural hematomas in the culprit vessel. We performed cutting balloon angioplasty successfully with dual intracoronary imaging modality guidance. The 4-month follow-up angiography revealed favorable vascular healing and the provocation test induced multiple spasms, including in the culprit vessel, by intracoronary acetylcholine administration. .

BACKGROUND Quantitative flow ratio (QFR) is a newly developed image-based index for estimating fractional flow reserve (FFR).Methods and Results:We analyzed 151 coronary arteries with intermediate stenosis in 142 patients undergoing wire-based FFR measurement using dedicated software. Predefined contrast flow QFR, which was derived from 3-dimensional quantitative coronary angiography (3-D QCA) withThrombolysis in Myocardial Infarction (TIMI) frame counts, was compared with FFR as a reference. QFR had good correlation (r=0.80, P

A 67-year old male with a dual-chamber pacemaker visited for a regular check-up. An unfamiliar message emerged on the display just after placing the programmer wand. We could recognize that the pacemaker had already been in the safe back-up mode of DDI, and the programmer prompted a re-initialization request. We are so surprised because there was no indication of device malfunction the day before in daily monitoring and a 12-lead electrocardiogram revealed normally working in the DDD mode just before checking the device. The pacemaker was immediately re-programmed to the former setting. This phenomenon has not recurred for 12 months. Keywords: Power-on reset, Electromagnetic interference, Pacemaker, Daily monitoring, Transmission interference

Slow-fast atrioventricular nodal tachycardia (AVNRT) has various electrophysiological aspects due to atrioventricular (AV) nodal physiology. In addition, concomitantly another form of arrhythmia with AVNRT, especially atrial tachycardia (AT), was an infrequent arrhythmia. A 38-year-old female with narrow QRS tachycardia underwent electrophysiological study due to frequent faintness. The electrophysiological study disclosed the coexistence of AT originating from coronary sinus (CS) with slow-fast AVNRT. We easily diagnosed AT originating from CS and terminated with several radiofrequency ablations (RFA) around CS. The diagnosis of slow-fast AVNRT, however, was somewhat difficult due to the following findings: (1) small amount of adenosine triphosphate (ATP) could terminate slow-fast AVNRT reproducibly; (2) we could provoke slow-fast AVNRT only by RV pacing with isoproterenol infusion. With other electrophysiological findings, we diagnosed slow-fast AVNRT. Radiofrequency energy was delivered initially in the posteroseptal region, followed by inside CS, and finally in the middle septal region, which completed the slow pathway ablation. After the procedure, we could never provoke these arrhythmias.

Although the global maternal mortality ratio has been consistently reduced over time, in 2015, there were still 303,000 maternal deaths throughout the world, of which 99% occurred in developing countries. Understanding pathophysiology of pregnancy complications contributes to the proper prenatal care for the reduction of prenatal, perinatal and neonatal mortality and morbidity ratio. In this review, we focus on AMP-activated protein kinase (AMPK) as a regulator of pregnancy complications. AMPK is a serine/threonine kinase that is conserved within eukaryotes. It regulates the cellular and whole-body energy homeostasis under stress condition. The functions of AMPK are diverse, and the dysregulation of AMPK is known to correlate with many disorders such as cardiovascular disease, diabetes, inflammatory disease, and cancer. During pregnancy, AMPK is necessary for the proper placental differentiation, nutrient transportation, maternal and fetal energy homeostasis, and protection of the fetal membrane. Activators of AMPK such as 5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR), resveratrol, and metformin restores pregnancy complications such as gestational diabetes mellitus (GDM), preeclampsia, intrauterine growth restriction, and preterm birth preclinically. We also discuss on the relationship between catechol-O-methyltransferase (COMT), an enzyme that metabolizes catechol, and AMPK during pregnancy. It is known that metformin cannot activate AMPK in COMT deficient mice, and that 2-methoxyestradiol (2-ME), a metabolite of COMT, recovers the AMPK activity, suggesting that COMT is a regulator of AMPK. These reports suggest the therapeutic use of AMPK activators for various pregnancy complications, however, careful analysis is required for the safe use of AMPK activators since AMPK activation could cause fetal malformation.

Background The role of p53 in the prevention of development of embryos damaged by genotoxic factors is well recognized. However, whether p53 plays an analogous role in preventing birth defects from genetic mutations remains an unanswered question. Genetic screens for mutations affecting development show that only a fraction of developmentally lethal mutations leads to specific phenotypes while the majority results in similar recurrent phenotypes characterized by neuronal apoptosis and developmental delay. Mutations in cell-essential genes typically fall into this group. The observation that mutations in diverse housekeeping genes lead to a similar phenotype suggests a common mechanism underlying this phenotype. For some mutants, p53 inhibition was shown to attenuate the phenotype. Methodology/Principal Findings To find out how common p53 involvement is in this phenotype, we analyzed zebrafish mutants from various categories of cell essential genes. Several thousand zebrafish mutants have been identified; many of them are kept at stock centers and available for the research community. We selected mutants for genes functioning in DNA replication, transcription, telomere maintenance, ribosome biogenesis, splicing, chaperoning, endocytosis, and cellular transport. We found that mutants have similar phenotypes including neural apoptosis, failure to develop structures originated from the neural crest cells, and hematopoietic defects. All mutants share p53 upregulation and similar changes in several p53-dependent and independent molecular pathways. Conclusion/Significance Our results suggest that mutations in housekeeping genes often canalize on the p53-mediated phenotype. p53 prevents the development of embryos with defects in such genes. p53-mediated changes in gene expression may also contribute to many human congenital malformations.