The impact of an empiric superior vena cava isolation added to pulmonary vein isolation for non-paroxysmal atrial fibrillation associated with left atrial low voltage areas

Introduction

Left atrial low-voltage areas (LVAs) are associated with recurrence after radiofrequency catheter ablation of atrial fibrillation (AF). However, the impact of LVAs on recurrence after an empiric pulmonary vein isolation (PVI) plus superior vena cava isolation (SVCI) strategy for non-Paroxysmal AF (PAF) patients remains unclear.

Purpose

We evaluated the impact of LVAs on the recurrence of atrial tachyarrhythmias (ATs)/AF in patients who underwent an empiric SVCI added to the PVI for non-PAF.

Methods

We enrolled 153 consecutive patients with non-PAF who underwent a PVI alone (PVI group; n=51) or empiric PVI plus SVCI (PVI+SVCI group; n=102). Left atrial voltage maps were constructed during sinus rhythm to identify the LVAs (<0.5 mV). No patients underwent a substrate modification of the LVAs. We divided the patients into two groups based on the LVAs (with or without an LVA >5% of the left atrial surface area) and investigated the ATs/AF free survival rate after the initial and multiple procedures.

Results

LVAs were identified in 65% and 73% of the PVI and PVI + SVCI groups, respectively (P=0.319). In the PVI group, the 18-month ATs/AF-free survival was 61% of the patients without LVAs and 27% of patients with LVAs after the initial session (P=0.018) (Figure 1-A). Seventy-two percent of the patients without LVAs and 46% of those with LVAs were free from ATs/AF after multiple sessions (P=0.083) (Figure 1-B). In the PVI+SVCI group, 50% of the patients with LVAs and 61% of those without LVAs had no recurrence after the initial session (P=0.374) (Figure 2-A). Moreover, there was no significant difference in the 18-month ATs/AF-free survival between the patients with and without LVAs after multiple sessions (73% vs. 79%; P=0.520) (Figure 2-B).

Conclusion

A PVI alone strategy for non-PAF patients with LVAs had limited efficacy for the outcomes, even with multiple procedures. However, an SVCI may have the potential to compensate for an impaired outcome in patients with LVAs.

Funding Acknowledgement

Type of funding source: None

International Expert Consensus Document on Takotsubo Syndrome (Part II): Diagnostic Workup, Outcome, and Management

The clinical expert consensus statement on takotsubo syndrome (TTS) part II focuses on the diagnostic workup, outcome, and management. The recommendations are based on interpretation of the limited clinical trial data currently available and experience of international TTS experts. It summarizes the diagnostic approach, which may facilitate correct and timely diagnosis. Furthermore, the document covers areas where controversies still exist in risk stratification and management of TTS. Based on available data the document provides recommendations on optimal care of such patients for practising physicians.

International Expert Consensus Document on Takotsubo Syndrome (Part I): Clinical Characteristics, Diagnostic Criteria, and Pathophysiology

Takotsubo syndrome (TTS) is a poorly recognized heart disease that was initially regarded as a benign condition. Recently, it has been shown that TTS may be associated with severe clinical complications including death and that its prevalence is probably underestimated. Since current guidelines on TTS are lacking, it appears timely and important to provide an expert consensus statement on TTS. The clinical expert consensus document part I summarizes the current state of knowledge on clinical presentation and characteristics of TTS and agrees on controversies surrounding TTS such as nomenclature, different TTS types, role of coronary artery disease, and etiology. This consensus also proposes new diagnostic criteria based on current knowledge to improve diagnostic accuracy.

International Expert Consensus Document on Takotsubo Syndrome (Part I): Clinical Characteristics, Diagnostic Criteria, and Pathophysiology

Takotsubo syndrome (TTS) is a poorly recognized heart disease that was initially regarded as a benign condition. Recently, it has been shown that TTS may be associated with severe clinical complications including death and that its prevalence is probably underestimated. Since current guidelines on TTS are lacking, it appears timely and important to provide an expert consensus statement on TTS. The clinical expert consensus document part I summarizes the current state of knowledge on clinical presentation and characteristics of TTS and agrees on controversies surrounding TTS such as nomenclature, different TTS types, role of coronary artery disease, and etiology. This consensus also proposes new diagnostic criteria based on current knowledge to improve diagnostic accuracy.

Lansoprazole prevents the progression of liver fibrosis in non-alcoholic steatohepatitis model rats

OBJECTIVES

We previously demonstrated that lansoprazole provided hepatoprotection in a drug-induced hepatitis animal model partially through the Nrf2/HO-1 pathway. Here, we examined whether lansoprazole could also provide hepatoprotection in a rat model of non-alcoholic steatohepatitis (NASH).

METHODS

Six-week-old rats were fed a normal chow or a choline-deficient amino acid-defined (CDAA) diet to establish a rat model of NASH. The groups fed a CDAA diet for 5 weeks were subcutaneously administered either a vehicle or a lansoprazole suspension for 4 weeks beginning the second week of the experiment.

KEY FINDINGS

Bridging fibrosis was observed in the livers of almost all the NASH model rats (six of seven), but it was not always observed in NASH model rats (one of seven) continuously administered lansoprazole. The serum aspartate aminotransferase level elevated by the CDAA diet was significantly decreased following lansoprazole administration. Lansoprazole also increased the expression of Nrf2, but not HO-1, in the liver of NASH model rats. Lansoprazole decreased the level of activated TGF-β protein. Furthermore, interleukin-6 gene and protein expression were decreased.

CONCLUSIONS

Lansoprazole inhibits hepatic fibrogenesis, at least during the early stages, in CDAA diet-induced NASH model rats. The mechanisms might be associated with cytokine suppression but not the inhibition of reactive oxygen species.

Effect of Ticlopidine on Graft Patency Following Arterial Reconstructive Surgery in the Lower Extremity: A Multicenter Three-Year Prospective Study

A multicenter, randomized, prospective trial was conducted to determine the clinical efficacy of ticlopidine, an antiplatelet agent, in the prevention of graft occlusion following vascular reconstructive surgery of the lower extremity for arteriosclerosis obliterans. Ticlopidine was administered for two years to one group of patients (112 reconstructed arterial segments) while a control group received no antithrombotic therapy (108 segments). There was no significant difference between the treated and control groups in the overall cumulative patency rates for both suprainguinal and infrainguinal reconstructions. In the treated group, however, there was a significant reduction of occlusions in pa tients with rest pain or ischemic gangrene (p < 0.1) and in those with hyperlipi demia (p < 0.05). Ticlopidine-treated patients with infrainguinal arterial reconstructions developed more occlusions than controls between three and twelve months after surgery, but the controls had more occlusions both immedi ately after surgery and in the second postoperative year. It appeared, therefore, that ticlopidine reduced graft failure due to neointimal fibrous hyperplasia or progression of the underlying condition but caused an adverse effect by delaying graft healing. The clinical usefulness of antiplatelet therapy is limited, but it may be effective in the prevention of graft occlusion when administered to the selected patient groups above mentioned. Controversy about antiplatelet ther apy and future research on adjuvant drug therapy after arterial reconstruction are discussed.

Gene expression profiling in rats with depressive-like behavior

Individual differences indicate stronger phenotypes than model animals especially in behavioral studies, and some animals show unexpected behaviors in control and animal model groups. High-throughput analysis including cDNA microarray analysis are more affected by individual differences, because more samples are needed to reduce the difference in multiple factor analysis than single factor analysis such as real-time PCR. We measured the depressive-like behavior of over 100 normal rats in the forced swimming test and selected the rats for control and depression group from them to minimize the individual difference using data of force swimming test. Here, we provided the detail of methods and quality control parameters for the cDNA microarray data. This dataset can reflect the increase of depressive-like behavior. The dataset is deposited in the gene expression omnibus (GEO), series GSE63377.

Downregulation of growth hormone 1 gene in the cerebellum and prefrontal cortex of rats with depressive-like behavior

Depressive-like behaviors in animals are usually assessed by standardized behavioral tests such as the forced swimming test (FST). However, individual variation in test performance may obscure group differences and thereby hinder the discovery of genes responsible for depression. Few reports have shown the influence of individual variability in identifying the genes associated with depressive-like behaviors. In this study, we conducted microarray analysis to identify genes differentially expressed in the prefrontal cortex (PFC) and cerebellum of rats stratified by FST immobility ratio (% immobility in 5 min) into a control group [immobility ratio: −1 to +1 standard deviation (SD) from the mean] and a depressive group (immobility ratio: +1 to +2 SDs above the mean). Genes differentially expressed in both the cerebellum and PFC of the depressive group were Alas2, Gh1, Hba-a2, Hbb, Hbb-b1, Hbe2, LOC689064, Mrps10, Mybpc, Olf6415, and Pfkb1. Ingenuity Pathway Analysis identified Gh1 as a hub gene in the networks of differentially expressed genes in both brain regions. This study indicates that the depressive-like behavior may be related to the decrease of Gh1 expression in the cerebellum and PFC.

Reduction of cortical excitability and increase of thalamic activity in a low-frequency rTMS treatment for chronic tinnitus

Low-frequency repetitive transcranial magnetic stimulation (rTMS) has received increasing attention for the treatment of tinnitus, but its therapeutic mechanisms are unclear. We performed low-frequency rTMS treatment for a patient with chronic tinnitus and examined changes of cortical excitability and cerebral blood flow using paired-pulse TMS and single-photon emission computed tomography. After the rTMS treatment, tinnitus loudness was decreased, cortical excitability was reduced, and blood flow in the thalamus was increased. Our results suggest that low-frequency rTMS treatment reduces tinnitus loudness by an inhibitory effect on the cortical excitability and a remote activation effect on the thalamus through the corticothalamic networks.

Semaphorin 4D induces vaginal epithelial cell apoptosis to control mouse postnatal vaginal tissue remodeling

The opening of the mouse vaginal cavity to the skin is a postnatal tissue remodeling process that occurs at approximately five weeks of age for the completion of female genital tract maturation at puberty. The tissue remodeling process is primarily composed of a hormonally triggered apoptotic process predominantly occurring in the epithelium of the distal section of the vaginal cavity. However, the detailed mechanism underlying the apoptotic induction remains to be elucidated. In the present study, it was observed that the majority of BALB/c mice lacking the class 4 semaphorin, semaphorin 4D (Sema4D), developed imperforate vagina and hydrometrocolpos resulting in a perpetually unopened vaginal cavity regardless of a normal estrogen level comparable with that in wild-type (WT) mice. Administration of β-estradiol to infant Sema4D-deficient (Sema4D^−/−) mice did not induce precocious vaginal opening, which was observed in WT mice subjected to the same β-estradiol administration, excluding the possibility that the closed vaginal phenotype was due to insufficient estrogen secretion at the time of vaginal opening. In order to assess the role of Sema4D in the postnatal vaginal tissue remodeling process, the expression of Sema4D and its receptor, plexin-B1, was examined as well as the level of apoptosis in the vaginal epithelia of five-week-old WT and Sema4D^−/− mice. Immunohistochemical analyses confirmed the localization of Sema4D and plexin-B1 in the mouse vaginal epithelia. Terminal deoxynucleotidyl transferase dUTP nick end labeling assay and immunohistochemistry detecting activated caspase-3 revealed significantly fewer apoptotic cells in situ in the vaginal mucosa of five-week-old Sema4D^−/− mice compared with WT mice. The addition of recombinant Sema4D to Sema4D^−/− vaginal epithelial cells in culture significantly enhanced apoptosis of the vaginal epithelial cells, demonstrating the apoptosis-inducing activity of Sema4D. The experimental reduction of plexin-B1 expression in vaginal epithelial cells demonstrated the integral role of plexin-B1 in Sema4D-induced apoptotic cell death. These results suggest a non-redundant role of Sema4D in the postnatal tissue remodeling process in five-week-old BALB/c mice, which involves the induction of vaginal epithelial cell apoptosis through Sema4D binding to plexin-B1.

Estrogen-dependent proteolytic cleavage of semaphorin 4D and plexin-B1 enhances semaphorin 4D-induced apoptosis during postnatal vaginal remodeling in pubescent mice

Around the fifth week after birth, the vaginal cavity in female mouse pups opens to the overlaying skin. This postnatal tissue remodeling of the genital tract occurs during puberty, and it largely depends upon hormonally induced apoptosis that mainly occurs in the epithelium at the lower part of the mouse vaginal cavity. Previously, we showed that most BALB/c mice lacking the class IV Semaphorin (Sema4D) develop imperforate vagina and hydrometrocolpos; therefore, we reasoned that the absence of Sema4D-induced apoptosis in vaginal epithelial cells may cause the imperforate vagina. Sema4D signals via the Plexin-B1 receptor; nevertheless detailed mechanisms mediating this hormonally triggered apoptosis are not fully documented. To investigate the estrogen-dependent control of Sema4D signaling during the apoptosis responsible for mouse vaginal opening, we examined structural and functional modulation of Sema4D, Plexin-B1, and signaling molecules by analyzing both wild-type and Sema4D−/− mice with or without ovariectomy. Both the release of soluble Sema4D and the conversion of Plexin-B1 by proteolytic processing in vaginal tissue peaked 5 weeks after birth of wild-type BALB/c mice at the time of vaginal opening. Estrogen supplementation of ovariectomized wild-type mice revealed that both the release of soluble Sema4D and the conversion of Plexin-B1 into an active form were estrogen-dependent and concordant with apoptosis. Estrogen supplementation of ovariectomized Sema4D−/− mice did not induce massive vaginal apoptosis in 5-week-old mice; therefore, Sema4D may be an essential apoptosis-inducing ligand that acts downstream of estrogen action in vaginal epithelium during this postnatal tissue remodeling. Analysis of ovariectomized mice also indicated that Sema4D contributed to estrogen-dependent dephosphorylation of Akt and ERK at the time of vaginal opening. Based on our results, we propose that apoptosis in vaginal epithelium during postnatal vaginal opening is induced by enhanced Sema4D signaling that is caused by estrogen-dependent structural changes of Sema4D and Plexin-B1.

Brain regions responsible for tinnitus distress and loudness: a resting-state FMRI study

Subjective tinnitus is characterized by the perception of phantom sound without an external auditory stimulus. We hypothesized that abnormal functionally connected regions in the central nervous system might underlie the pathophysiology of chronic subjective tinnitus. Statistical significance of functional connectivity (FC) strength is affected by the regional autocorrelation coefficient (AC). In this study, we used resting-state functional MRI (fMRI) and measured regional mean FC strength (mean cross-correlation coefficient between a region and all other regions without taking into account the effect of AC (rGC) and with taking into account the effect of AC (rGCa) to elucidate brain regions related to tinnitus symptoms such as distress, depression and loudness. Consistent with previous studies, tinnitus loudness was not related to tinnitus-related distress and depressive state. Although both rGC and rGCa revealed similar brain regions where the values showed a statistically significant relationship with tinnitus-related symptoms, the regions for rGCa were more localized and more clearly delineated the regions related specifically to each symptom. The rGCa values in the bilateral rectus gyri were positively correlated and those in the bilateral anterior and middle cingulate gyri were negatively correlated with distress and depressive state. The rGCa values in the bilateral thalamus, the bilateral hippocampus, and the left caudate were positively correlated and those in the left medial superior frontal gyrus and the left posterior cingulate gyrus were negatively correlated with tinnitus loudness. These results suggest that distinct brain regions are responsible for tinnitus symptoms. The regions for distress and depressive state are known to be related to depression, while the regions for tinnitus loudness are known to be related to the default mode network and integration of multi-sensory information.

Is gastrectomy-induced high turnover of bone with hyperosteoidosis and increase of mineralization a typical osteomalacia?

Gastrectomy (GX) is thought to result in osteomalacia due to deficiencies in Vitamin D and Ca. Using a GX rat model, we showed that GX induced high turnover of bone with hyperosteoidosis, prominent increase of mineralization and increased mRNA expression of both osteoclast-derived tartrate-resistant acid phosphatase 5b and osteocalcin. The increased 1, 25(OH)2D3 level and unchanged PTH and calcitonin levels suggested that conventional bone and Ca metabolic pathways were not involved or changed in compensation. Thus, GX-induced bone pathology was different from a typical osteomalacia. Gene expression profiles through microarray analysis and data mining using Ingenuity Pathway Analysis indicated that 612 genes were up-regulated and 1,097 genes were down-regulated in the GX bone. These genes were related functionally to connective tissue development, skeletal and muscular system development and function, Ca signaling and the role of osteoblasts, osteoclasts and chondrocytes. Network analysis indicated 9 genes (Aldehyde dehydrogenase 1 family, member A1; Aquaporin 9; Interleukin 1 receptor accessory protein; Very low density lipoprotein receptor; Periostin, osteoblast specific factor; Aggrecan; Gremlin 1; Angiopoietin-like 4; Wingless-type MMTV integration site family, member 10B) were hubs connected with tissue development and immunological diseases. These results suggest that chronic systemic inflammation might underlie the GX-induced pathological changes in bone.

Amlodipine has a preventive effect on temporal left ventricular hypokinesia after emotional stress compared with an angiotensin II receptor blocker

PURPOSE

We previously reported that α- and β-blockers protected against emotional stress-induced cardiac dysfunction, but the protective effects of other antihypertensive drugs is unknown. The purpose of this study is to evaluate the ability of a calcium channel blocker, amlodipine, to prevent temporal left ventricular hypokinesia after emotional stress compared with an angiotensin II receptor blocker, olmesartan medoxomil.

METHODS

Rats premedicated with amlodipine (0.2 mg/kg), olmesartan (0.8 mg/kg), or vehicle were restrained for 30 min (immobilization stress: IMO) to reproduce emotional stress and then anesthetized to release stress. We measured the fractional area change (FAC) using echocardiography (SONOS5500) with a s12 probe (frequency 5-12 MHz, frame rate 120 Hz) and blood pressure and heart rate at the end of IMO and every 10 for 60 min after IMO.

RESULTS

During IMO, FAC in the amlodipine or the olmesartan group was as high as that in the vehicle group. At 20 min after IMO, FAC in the amlodipine group was significantly higher than in the other two groups (84 ± 8 vs. 60 ± 7 or 68 ± 15 %, p < 0.05). During IMO, blood pressure in the amlodipine or the olmesartan group was significantly lower than with vehicle (119 ± 6 and 110 ± 7 vs. 124 ± 5 mmHg, p < 0.05). After IMO, blood pressure in the olmesartan group was significantly lower than in the other two groups.

CONCLUSION

Acute administration of amlodipine could prevent a sudden drop in cardiac function after acute stress like IMO, but olmesartan did not. Amlodipine might have a protective effect on temporal left ventricular hypokinesia after emotional stress, which might not be related to decreased blood pressure.

[Emotion, amygdala, and autonomic nervous system]

Emotion refers to the dynamic changes of feeling accompanied by the alteration of physical and visceral activities. Autonomic nervous system (sympathetic and parasympathetic) regulates the visceral activities. Therefore, monitoring and analyzing autonomic nervous activity help understand the emotional changes. To this end, the survey of the expression of immediate early genes (IEGs), such as c-Fos in the brain and target organs, and the viral transneuronal labeling method using the pseudorabies virus (PRV) have enabled the visualization of the neurocircuitry of emotion. By comparing c-Fos expression and data from PRV or other neuroanatomical labeling techniques, the central sites that regulate emotional stress-induced autonomic activation can be deduced. Such regions have been identified in the limbic system (e. g., the extended amygdaloid complex; lateral septum; and infralimbic, insular, and ventromedial temporal cortical regions), as well as in several hypothalamic and brainstem nuclei. The amygdala is structurally diverse and comprises several subnuclei, which play a role in emotional process via projections from the cortex and a variety of subcortical structures. All amygdaloid subnuclei receive psychological information from other limbic systems, while the lateral and central subnuclei receive peripheral and sensory information. Output to the hypothalamus and peripheral sympathetic system mainly originates from the medial amygdala. As estrogen receptor α, estrogen receptor β, and androgen receptor are expressed in the medial amygdala, sex steroids may modulate the autonomic nervous activities.

[Limbic system and autonomic nervous system]

The viral transneuronal labeling method using pseudorabies virus (PRV) is an ideal technique for identifying the central sites that regulate the sympathetic nervous system. Regions were identified in limbic system such as extended amygdaloid complex, lateral septum, infralimbic, insular, ventromedial temporal cortical regions, as well as in several hypothalamic and brain stem nuclei. Emotional stress causes rapid and transient expression of immediate early genes (IEGs) such as c-Fos in the brain, and the monitoring of IEGs has enabled the visualization of the neurocircuitry of stress. By a comparison of the data from the separate PRV and c-Fos neuroanatomical labeling techniques, the central sites which regulate emotional stress-induced sympathoadrenal activation can be deduced. Estrogen receptors are expressed in the brain, where estrogen modulates central nervous function and autonomic nervous function. Estrogen attenuated the stress-induced c-Fos expression in medial amygdaloid nucleus, paraventricular hypothalamic nucleus; these same regions contain central sympathetic neurons and neurons with immunoreactive estrogen receptors.

Restraint stress induces connexin-43 translocation via α-adrenoceptors in rat heart

BACKGROUND

Immobilization (IMO) confers emotional stress in animals and humans. It was recently reported that IMO in rats induced translocation of connexin-43 (Cx43) to gap junctions (GJs) and attenuated arrhythmogenesis with GJ inhibition, and Cx43 translocation in the ischemic heart was also shown. Few reports show the contribution of adrenoceptors to Cx43 upregulation in cardiomyocytes, but the involvement of adrenoceptors and ischemia in Cx43 translocation in IMO remains elusive.

METHODS AND RESULTS

Male Sprague-Dawley rats underwent IMO and the ventricular distribution of Cx43 was examined by western blotting. IMO induced translocation of Cx43 to the GJ-enriched membrane fraction, with a peak at 60min. The IMO-induced Cx43 translocation was inhibited by pretreatment with the α(1)-adrenoceptor blockers, prazosin (1mg/kg, PO) and bunazosin (4mg/kg, PO), but not with either the β(1)-blocker, metoprolol (10mg/kg, IP), or the β(1+2)-blocker, propranolol (1mg/kg, PO). The translocation was inhibited by the nitric oxide, donor isosorbide dinitrate (100µg·kg(-1)·min(-1), IV), possibly through sympathetic inhibition. Hypoxia inducible factor-1α was not redistributed by IMO. The β-blockers, but not the α-blockers, inhibited the premature ventricular contractions (PVCs) induced by IMO.

CONCLUSIONS

Translocation of Cx43 to the GJ-enriched fraction occurs via the α(1)-adrenoceptor pathway, independently of ischemia. The β-adrenoceptor pathway contributes to the inducing of PVCs in IMO.

Stress cardiomyopathy

Recently, an increasing number of cases of stress cardiomyopathy, mainly occurring in elderly women, have been documented in many parts of the world. In Japan, this disease is known as takotsubo cardiomyopathy (named after the fishing pot used for trapping octopus). Symptoms of this condition are akin to those of acute myocardial infarction, but no obstructive lesions are found in the coronary arteries, and left ventricular apical ballooning is present. Stress cardiomyopathy is now a well-recognized cause of acute heart failure, lethal ventricular arrhythmias, and ventricular rupture. Although the precise mechanism of onset of this condition is still controversial, two major pathogenic mechanisms have been proposed: catecholamine cardiotoxicity and neurogenic stunned myocardium. We summarize the findings of studies conducted to date on stress cardiomyopathy-from bench to bedside and bedside to bench.

Connexin-43 redistribution and gap junction activation during forced restraint protects against sudden arrhythmic death in rats

BACKGROUND

Connexin-43 (Cx43) expression is reduced or redistributed in heart disease. Restraint or other emotional stressors might cause sudden death in persons with such diseases, but the mechanism of death and its connection to Cx43 during restraint remain unknown. Whether Cx43 distribution or gap junction (GJ) function during restraint is involved in sudden arrhythmic death in rats is addressed in this study.

METHODS AND RESULTS

Male Sprague-Dawley rats underwent immobilization (IMO), and individual electrocardiographic responses were monitored by telemetry. Heart sections were used to examine ventricular Cx43 distribution, and GJ intercellular communication (GJIC) activity was assessed using a dye-transfer assay. IMO induced the translocation of Cx43 into to the GJ-rich fraction, with a peak at 60 min. During IMO, Cx43 immunofluorescence was enhanced at intercalated discs, in association with GJIC activation, and premature ventricular contractions (PVCs) increased. In the presence of the GJ inhibitor, carbenoxolone (0.25 mg.kg(-1).h(-1)), IMO induced lethal ventricular tachycardia or fibrillation in 21.7% of rats, in association with QRS prolongation and increased PVCs.

CONCLUSIONS

IMO causes Cx43 translocation to intercalated discs, thereby reducing vulnerability to lethal arrhythmias via enhancing GJ coupling.

Pleiotropic effects of mitiglinide in type 2 diabetes mellitus

This study investigated the effects of mitiglinide in 16 patients with type 2 diabetes mellitus treated with 30 mg/day mitiglinide, divided into three doses given just before each meal, for approximately 12 months. A 450 kcal meal tolerance test was performed at baseline and after 3, 6 and 12 months, and levels of plasma glucose and immunoreactive insulin were measured. Various parameters of glucose metabolism and lipid metabolism, urinary albumin and markers of atherosclerosis, coagulation and fibrinolysis were also determined. Mitiglinide showed a rapid stimulatory effect on insulin secretion and reduced the levels of plasma glucose. The free fatty acid level significantly decreased at 60 min after the meal tolerance test. Mitiglinide also significantly lowered glycosylated haemoglobin and raised 1,5-anhydroglucitol after 6 months, and significantly decreased urinary albumin after 12 months. These data indicate that mitiglinide may have beneficial effects not only on glycaemic control but also on lipid metabolism and urinary albumin excretion, and may have a role in the prevention of the vascular complications of diabetes.

Polaprezinc (Zinc L-carnosine) is a potent inducer of anti-oxidative stress enzyme, heme oxygenase (HO)-1 - a new mechanism of gastric mucosal protection

Heme oxygenase (HO)-1 is implicated in cytoprotection in various organs. We tested a possibility that polaprezinc (PZ), an anti-ulcer drug, could induce HO-1 in the gastric mucosa. Male 6-week-old Wistar rats were intragastrically administered PZ. Gastric expression of HO-1 was assessed by real time RT-PCR and western blotting, and localization of HO-1 was observed by in situ hybridization and immunohistochemistry. The levels of HO-1 mRNA were increased in a dose-dependent manner. The levels of HO-1 mRNA were increased 4-fold by PZ at the dose of 200 mg/kg at 3 h as compared with control levels. The levels of immunoreactive HO-1 were increased 3-fold at 6 h. Signals for HO-1 mRNA and immunoreactivity were detected strongly in the surface gastric mucosal cells and moderately in the gastric macrophages. Treatment with an HO-1 inhibitor, stannous mesoporphyrin (SnMP) significantly worsened the HCl-induced acute gastric mucosal lesions and increased the apoptosis of mucosal cells. Mucosal lesions were decreased by pretreatment with PZ, while they were increased by co-administration with SnMP. These data indicate for the first time that PZ is an effective inducer of HO-1 in the stomach. PZ-induced HO-1 functions as a part of the mucosal protective effects of PZ.

Upregulation of heme oxygenase-1 in an animal model of Takotsubo cardiomyopathy

BACKGROUND

Disturbance of the coronary microcirculation and catecholamine intoxication, which may be responsible for the pathogenesis of takotsubo cardiomyopathy, could trigger an oxidative stress response in the heart.

METHODS AND RESULTS

Expression and localization of inducible heme oxygenase-1 (HO-1), which is an oxidative stress-related factor in the heart of immobilization stressed (IMO) rats, an animal model of takotsubo cardiomyopathy, were investigated by real-time reverse transcriptase-polymerase chain reaction and in situ hybridization histochemistry and immunohistochemistry. In response to IMO, the levels of HO-1 mRNA in the heart and in the aorta were slightly increased at 90 min, and increased 3-fold at 3 h compared with control levels. The signals for HO-1 mRNA were expressed on scatted cells in the myocardium and aortic adventitia. Double fluorescence immunohistochemistry showed that HO-1 immunoreactive cells were also ED1 and ED2 positive, indicating that they were macrophages. The numbers of ED1 and ED2 positive cells were constant, whereas the number of HO-1 positive cells was increased 5-fold at 6 h compared with control levels. Blocking of alpha- and beta-adrenoceptors attenuated IMO-induced upregulation of HO-1 mRNA levels in the heart.

CONCLUSIONS

Emotional stress and a surge of catecholamine upregulate HO-1 in the cardiac and aortic macrophages.

Vasospastic angina induced by nonsteroidal anti-inflammatory drugs

We report two cases of vasospastic angina associated with anaphylactic reaction caused by nonsteroidal anti-inflammatory drugs (NSAIDs). Both patients exhibited anaphylactic manifestations, such as general rash and urticaria, along with angina pectoris with electrocardiographic ST-segment elevations after suppository administration of diclofenac sodium or indomethacin, the most commonly used NSAIDs. Although these patients had normal coronary arteriograms, intracoronary administration of ergonovine or acetylcholine provoked diffuse coronary artery spasms accompanied by chest pain and ischemic ST-segment changes. It is therefore suggested that an allergic mechanism may be involved as a causative factor of the coronary artery spasm induced by NSAIDs.

Catecholamines and estrogen are involved in the pathogenesis of emotional stress-induced acute heart attack

Emotional stress triggers takotsubo cardiomyopathy in postmenopausal women. Clinical analysis of autonomic nervous function has revealed a transient increase of sympathetic nervous activity and decrease of vagal nervous activity. Immobilization (IMO) stress of rats can reproduce the electrocardiographic and left ventriculographic changes that occur in takotsubo cardiomyopathy, both of which are prevented by combined blockade of alpha- and beta-adrenoceptors. Estrogen supplementation partially attenuated these cardiac changes. It also attenuated the IMO-induced increase of c-Fos immunoreactivity, or c-fos mRNA expression in the lateral septum, medial amygdaloid nucleus, paraventricular hypothalamic nucleus, dorsomedial hypothalamic nucleus, laterodorsal tegmental nucleus, and locus ceruleus; these regions contain central sympathetic neurons and neurons with immunoreactive estrogen receptors. It also downregulated c-fos mRNA expression in the adrenal gland and the heart, suggesting an increase of estrogen attenuated the stress-induced hypothalamo-sympathoadrenal outflow from the central nervous system to the target organs. Estrogen treatment also upregulated the levels of cardioprotective substances, such as atrial natriuretic peptide and heat shock protein 70, in the heart. These data suggest that reduction of estrogen levels following menopause might be involved in the primary cause of takotsubo cardiomyopathy both by indirect action on the nervous system and by direct action on the heart.

Effects of estrogen on stress-induced activation of peptide neurons in PVN of ovariectomized rats

Estrogen has been implicated in brain function related to stress responses. We investigated whether estrogen affects psychological stress-induced activation of peptide-containing or nitric oxide-producing neurons in the paraventricular hypothalamic nucleus (PVN) in ovariectomized (OVX) rats, both placebo-treated (OVX + Pla) and estrogen-treated (OVX + E2) by comparison of c-Fos expression using immunohistochemistry. Cage-switch stress increased activation in oxytocinergic neurons in the parvocellular PVN (pPVN) in OVX + Pla, but not in that of OVX + E2, rats. Moreover, the stress-induced activation in NADPH-diaphorase-positive neurons in the pPVN was larger in the OVX + E2 than in the OVX + Pla group. These findings suggest that estrogen attenuates the activation of oxytocinergic neurons in the pPVN, at least in part via nitric oxide.

Adaptive HNE-Nrf2-HO-1 pathway against oxidative stress is associated with acute gastric mucosal lesions

Disturbance of the microcirculation and generation of reactive oxygen species are crucial in producing acute gastric mucosal lesions (AGML). To understand the protective mechanism against mucosal injury and oxidative stress in the stomach, we investigated sequential expression and localization of a product of lipid peroxidation and a chemical mediator of the oxidative response array, 4-hydroxynonenal (HNE), transcriptional factor, NF-E2-related factor (Nrf2), and the inducible heme oxygenase (HO-1) in the injured stomach. AGML was produced by intragastric administration of 0.6 N HCl in male rats. Expression and localization of HNE, Nrf2, and HO-1 were investigated by Western blotting, immunohistochemistry, real-time RT-PCR, and in situ hybridization histochemistry. Mucosal lesions and expression of HNE and HO-1 were assessed by prior treatment with the PGI2 analog beraprast or after sensory denervation by pretreatment with capsaicin. Mucosal lesions were assessed by prior treatment with a HO-1 inhibitor, zinc protoporphyrin (ZnPP). After AGML, increased generation of HNE was observed in the injured mucosa and the surrounding submucosa, followed by nuclear translocation of Nrf2 and upregulation of HO-1 in the macrophages located in the margin of the injured mucosa and in the submucosa. Pretreatment with beraprost attenuated AGML and downregulated the expression of HNE and HO-1, while sensory denervation aggravated AGML and upregulated the expression of HNE and HO-1. Pretreatment with ZnPP also aggravated AGML. The sequential HNE-Nrf2-HO-1 pathway in the gastric mucosal cells and the macrophages is involved in an adaptive mechanism against oxidative stress after AGML.

AP-1 expression in ethanol-treated corneal epithelium in vivo

PURPOSE

To examine the expression pattern of stress-related genes, c-fos and c-jun, both the major components of activator protein-1 (AP-1), in rat corneal epithelium treated with a short-term ethanol exposure. The purpose of the current study was to examine if the ethanol exposure during laser epithelial keratomileusis (LASEK) may stimulate or damage the corneal epithelial cells.

METHOD

Sixty male Wistar rats were used. Fifty microliters of 20% ethanol was placed onto a surface 2.4 mm in diameter of the central corneal epithelium for 30 s. The affected eyes, washed with saline, were then enucleated after various intervals of healing. To know the expression pattern of c-fos and c-jun mRNAs and c-Fos, c-Jun and Jun D proteins, in situ hybridization and immunohistochemistry were carried out. The expression level of c-fos and c-jun mRNAs was determined by real-time reverse-transcriptase polymerase chain reaction (RT-PCR). Apoptotic nuclei in the tissue sections were identified by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) assay.

RESULTS

Thirty to 60 min after the treatment, c-fos and c-jun mRNAs were detected in the corneal epithelium. These signals were no longer evident at 90 min. c-Fos protein was detected in the corneal epithelium around the area of ethanol exposure from 60 to 120 min after the treatment, while c-Jun protein was not detected. Jun D protein was detected in control whole corneal epithelium and not affected by ethanol exposure in the periphery. The levels of c-fos and c-jun mRNAs were increased approximately 8 times at 30 min compared with the control level. TUNEL-positive apoptotic nuclei in the tissue sections were identified.

CONCLUSION

Corneal epithelial cells, especially those surrounding the ethanol-exposed area, are transiently transcriptionally activated at a very early phase after the ethanol exposure. mRNA expression for c-fos is followed by protein synthesis, but that of c-jun is not followed by protein synthesis. Resistance of Jun D protein expression to ethanol suggests that it might be a candidate for an AP-1 complex with c-Fos.

Chronic Estrogen Supplementation Following Ovariectomy Improves the Emotional Stress-Induced Cardiovascular Responses by Indirect Action on the Nervous System and by Direct Action on the Heart

BACKGROUND

Takotsubo cardiomyopathy is triggered by emotional or physical stress especially in post-menopausal women. A reduction in estrogen levels following menopause might underlie the high incidence of takotsubo cardiomyopathy.

METHODS AND RESULTS

The left ventricular contraction between ovariectomized rats (OVX) and OVX with estrogen supplementation (OVX + E) while subjected to immobilization stress (IMO) was compared. The IMO in combination with general anesthesia impaired the left ventricular contraction in both OVX and OVX + E. Estrogen supplementation tended to improve the IMO-induced cardiac dysfunction and significantly attenuated the increase of blood pressure and heart rate. To understand the protective mechanism of estrogen, the expression of c-fos mRNA, a marker of cellular activation was compared. The mRNA expression of cardioprotective substances in the heart was also investigated. In the OVX + E, the levels of c-fos mRNA were significantly decreased in the paraventricular hypothalamic nucleus, adrenal gland and left ventricle, suggesting that an increase of estrogen attenuates the emotional stress-induced hypothalamo-sympatho-adrenal outflow from the central nervous system to the target organs. An expression of heat shock protein 70 and atrial natriuretic peptide was significantly augmented in the OVX + E.

CONCLUSIONS

These data suggest that estrogen supplementation partially prevents emotional stress-induced cardiovascular responses both by indirect action on the nervous system and by direct action on the heart.

[Pacemaker implanted in right inguinal region following removal of infected generator; report of a case]

We treated a 62-year-old male who had previously undergone a mitral valve plasty and aorto-coronary bypass. One year after the operation, he underwent pacemaker implantation for atrial fibrillation. Two months following implantation, the pacemaker generator was exposed due to a methicillin-resistant Staphylococcus aureus (MRSA) infection. We selected a new catheter route from the right saphenous vein, and implanted a generator under the fascia of the external oblique abdominal muscle. Thereafter, the pacemaker is functioning without trouble and there is no evidence of infection.

Persistent median artery in the hand: A report with a brief review of the literature

We encountered a persistent median artery in the forearms and hands bilaterally in a 78-year-old Japanese male cadaver during dissection practice at Wakayama Medical University. The brachial arteries divided into the ulnar and radial arteries. The ulnar artery gave off the median and posterior interosseous arteries at the same point, although the anterior interosseous artery was not found. The median artery ran along the median nerve and bifurcated in the hand. In the superficial layer of the palm, one branch of the median artery ran to the ulnar side of the thumb, whereas the other passed to the second interdigital space. The ulnar artery reached the third and fourth interdigital spaces and the ulnar side of the little finger, and showed no anastomosis with the median artery in the superficial layer of the palm. The radial artery did not give off the superficial palmar branch. Therefore, the formation of the superficial palmar arch was incomplete. In the deep layer of the palm, the radial artery formed the deep palmar arch with the deep palmar branch of the ulnar artery and gave off the princeps pollicis artery. In the dorsum of hand, the radial artery passed over the first dorsal interosseous muscle to the index finger and communicated with the palmar pollical artery from the median artery in the first interosseous space. The present study reports an unusual variation of the persistent median artery in the hand and briefly reviews the literature about the median artery.

Cyclooxygenase 2 expression in rat corneas after ethanol exposure

PURPOSE

To evaluate the effects of ethanol exposure of the cornea on inflammation in corneal epithelium.

SETTING

Department of Ophthalmology, Wakayama Medical University, Wakayama, Japan.

METHODS

One cornea of Wistar rats (n = 60) was exposed to ethanol 20% for 30 seconds. The animals were killed 0.5, 1.0, 1.5, 2.0, 6.0, 12.0, 24.0, 48.0, or 72.0 hours or 7 days after treatment. The paraffin section or cryosection of the treated eyes was processed for histology; immunohistochemistry for cyclooxygenase 2 (COX2); p65 subunit of nuclear factor kappa B (NF-kappaB), which is the major transcription factor involved in COX2 expression; phospho-IkappaB; or in situ hybridization for COX2 mRNA.

RESULTS

In the uninjured corneas, faint immunoreactivity for COX2 was detected in the basal cells of the corneal epithelium, but not in other cell layers. Cyclooxygenase 2 mRNA was not observed in the injured epithelium; it was expressed 2 hours after ethanol exposure, but not 3 hours or later after treatment. The COX2 protein was detected in the corneal epithelium throughout the epithelial layers from 3 to 72 hours, but not at 7 days. The p65 of NF-kappaB translocated to the nuclei of corneal epithelium 3 to 24 hours after treatment but was not seen in the nuclei 48 hours after treatment. Phospho-I kappaB was detected in corneal epithelium 6 hours after treatment, but not 12 hours or later.

CONCLUSION

Ethanol exposure activated NF-kappaB and upregulated COX2 expression, which may cause inflammation in corneal tissue.