Selective activation of PPARα maintains thermogenic capacity of beige adipocytes

Beige adipocytes are inducible thermogenic adipocytes used for anti-obesity treatment. Beige adipocytes rapidly lose their thermogenic capacity once external cues are removed. However, long-term administration of stimulants, such as PPARγ and β-adrenergic receptor agonists, is unsuitable due to various side effects. Here, we reported that PPARα pharmacological activation was the preferred target for maintaining induced beige adipocytes. Pemafibrate used in clinical practice for dyslipidemia was developed as a selective PPARα modulator (SPPARMα). Pemafibrate administration regulated the thermogenic capacity of induced beige adipocytes, repressed body weight gain, and ameliorated impaired glucose tolerance in diet-induced obese mouse models. The transcriptome analysis revealed that the E-twenty-six transcription factor ELK1 acted as a cofactor of PPARα. ELK1 was mobilized to the Ucp1 transcription regulatory region with PPARα and modulated its expression by pemafibrate. These results suggest that selective activation of PPARα by pemafibrate is advantageous to maintain the function of beige adipocytes.

Genetic Risk of Primary Aldosteronism and Its Contribution to Hypertension: A Cross-Ancestry Meta-Analysis of Genome-Wide Association Study

BACKGROUND

Hypertension imposes substantial health and economic burden worldwide. Primary aldosteronism (PA) is one of the most common causes of secondary hypertension, causing cardiovascular events at higher risk compared with essential hypertension. However, the germline genetic contribution to the susceptibility of PA has not been well elucidated.

METHOD

We conducted a genome-wide association analysis of PA in the Japanese population and a cross-ancestry meta-analysis combined with UK Biobank and FinnGen cohorts (816 PA cases and 425 239 controls) to identify genetic variants that contribute to PA susceptibility. We also performed a comparative analysis for the risk of 42 previously established blood pressure-associated variants between PA and hypertension with the adjustment of blood pressure.

RESULTS

In the Japanese genome-wide association study, we identified 10 loci that presented suggestive evidence for the association with the PA risk (P<1.0×10^-6). In the meta-analysis, we identified 5 genome-wide significant loci (1p13, 7p15, 11p15, 12q24, and 13q12; P<5.0×10^-8), including 3 of the suggested loci in the Japanese genome-wide association study. The strongest association was observed at rs3790604 (1p13), an intronic variant of WNT2B (odds ratio, 1.50 [95% CI, 1.33-1.69]; P=5.2×10^-11). We further identified 1 nearly genome-wide significant locus (8q24, CYP11B2), which presented a significant association in the gene-based test (P=7.2×10^-7). Of interest, all of these loci were known to be associated with blood pressure in previous studies, presumably because of the prevalence of PA among individuals with hypertension. This assumption was supported by the observation that they had a significantly higher risk effect on PA than on hypertension. We also revealed that 66.7% of the previously established blood pressure-associated variants had a higher risk effect for PA than for hypertension.

CONCLUSIONS

This study demonstrates the genome-wide evidence for a genetic predisposition to PA susceptibility in the cross-ancestry cohorts and its significant contribution to the genetic background of hypertension. The strongest association with the WNT2B variants reinforces the implication of the Wnt/β-catenin pathway in the PA pathogenesis.

Association of DNA methylation with steroidogenic enzymes in Cushing's adenoma

DNA methylation and demethylation regulate the transcription of genes. DNA methylation-associated gene expression of adrenal steroidogenic enzymes may regulate cortisol production in cortisol-producing adenoma (CPA). We aimed to determine the DNA methylation levels of all genes encoding steroidogenic enzymes involved in CPA. Additionally, the aims were to clarify the DNA methylation-associated gene expression and evaluate the difference of CPA genotype from others using DNA methylation data. Twenty-five adrenal CPA and six nonfunctioning adrenocortical adenoma (NFA) samples were analyzed. RNA sequencing and DNA methylation array were performed. The methylation levels at 118 methylation sites of the genes were investigated, and their methylation and mRNA levels were subsequently integrated. Among all the steroidogenic enzyme genes studied, CYP17A1 gene was mainly found to be hypomethylated in CPA compared to that in NFA, and the Benjamini-Hochberg procedure demonstrated that methylation levels at two sites in the CYP17A1 gene body were statistically significant. PRKACA mutant CPAs predominantly exhibited hypomethylation of CYP17A1 gene compared with the GNAS mutant CPAs. Inverse associations between CYP17A1 methylation in three regions of the gene body and its mRNA levels were observed in the NFAs and CPAs. In applying clustering analysis using CYP17A1 methylation and mRNA levels, CPAs with PRKACA mutation were differentiated from NFAs and CPAs with a GNAS mutation. We demonstrated that CPAs exhibited hypomethylation of the CYP17A1 gene body in CPA, especially in the PRKACA mutant CPAs. Methylation of CYP17A1 gene may influence its transcription levels.

Hypomethylation associated vitamin D receptor expression in ATP1A1 mutant aldosterone-producing adenoma

DNA methylation alteration is tissue-specific and play a pivotal role in regulating gene transcription during cell proliferation and survival. We aimed to detect genes regulated by DNA methylation, and then investigated whether the gene influenced cell proliferation or survival in adrenal cells. DNA methylation and qPCR analyses were performed in nonfunctioning adrenocortical adenoma (NFA, n = 12) and aldosterone-producing adenoma (APA, n = 35) samples. The VDR gene promoter was markedly hypomethylated in APA with ATP1A1 mutation, and the promoter methylation levels showed a significant inverse association with the transcripts in APA. ATP1A1 mutation led to VDR transcription in HAC15 cells, and VDR suppression abrogated ATP1A1 mutation-mediated cell proliferation in HAC15 cells. We demonstrated that APA with ATP1A1 mutation showed entire hypomethylation in the VDR promoter and abundant VDR mRNA and protein expression. VDR suppression abrogated ATP1A1 mutation-mediated cell proliferation in HAC15 cells. Abundant VDR expression would be essential for ATP1A1 mutation-mediated cell proliferation.

Genotype-specific cortisol production associated with Cushing's syndrome adenoma with PRKACA mutations

The intracellular molecular mechanisms underlying the genotype of cortisol-producing adenoma (CPA) have not been fully determined. We analyzed gene expressions in CPA and the human adrenocortical cell line (HAC15 cells) with PRKACA mutation. Clustering analysis using a gene set associated with responses to cAMP revealed the possible differences between PRKACA mutant CPAs and GNAS and CTNNB1 mutant CPAs. The levels of STAR, CYP11A1, CYP17A1, CYP21A2, and FDX1 transcripts and cortisol levels per unit area in PRKACA mutant CPAs were significantly higher than those in GNAS mutant CPAs. PRKACA mutations led to an increase in steroidogenic enzyme expression and cortisol production in HAC15 cells. Transcriptome analysis revealed differences between PRKACA mutant CPAs and GNAS and CTNNB1 mutant CPAs. Cortisol production in PRKACA mutant CPAs is increased by the cAMP-PKA signaling pathway-mediated upregulation of steroidogenic enzymes transcription. The intracellular molecular mechanisms underlying these processes would be notably important in PRKACA mutant CPAs.

Variation in plasma glucagon levels according to obesity status in Japanese Americans with normal glucose tolerance

Japanese Americans living in the United States are genetically identical to Japanese people, but have undergone a rapid and intense westernization of their lifestyle. This study investigated variability in glucagon secretion after glucose loading among Japanese Americans with normal glucose tolerance (NGT) according to obesity status. The 75-g oral glucose tolerance test (OGTT) was performed for 138 Japanese Americans (aged 40-75 years) living in Los Angeles. Plasma glucagon levels measured using the sandwich enzyme-linked immunosorbent assay were compared according to body mass index (BMI) categories among 119 individuals with NGT. The individuals were classified into three categories according to their BMI values: <22 kg/m² (n = 37), 22-24.9 kg/m² (n = 46), and ≥25 kg/m² (n = 36). Fasting plasma glucagon levels and glucagon-area under the curve levels during the OGTT were the highest in the BMI ≥25 kg/m² group. Fasting glucagon levels were correlated with BMI (r = 0.399, p < 0.001), fasting insulin levels (r = 0.275, p = 0.003) and the homeostasis model assessment-insulin resistance (r = 0.262, p = 0.004). In conclusion, our findings suggest that fasting hyperglucagonemia is associated with obesity and insulin resistance even during the NGT stage in the Japanese American population.

Long-term effects of non-retrieved inferior vena cava filters on recurrences of venous thromboembolism in cancer and non-cancer patients: From the COMMAND VTE registry

BACKGROUND

There is a paucity of data comparing the long-term outcomes after inferior vena cava (IVC) filters placement for patients with acute venous thromboembolism (VTE) between those with and without active cancer.

METHODS

In the COMMAND VTE Registry, we evaluated the effects of IVC filter use on the long-term clinical outcomes stratified by the presence and absence of active cancer.

RESULTS

Among 2,626 patients with acute symptomatic VTE, there were 604 patients with active cancer, and 2022 patients without active cancer. IVC filters were placed and not retrieved in 455 patients (17%) in the entire cohort, in 150 patients (24.8%) in the active cancer stratum, and in 305 patients (15.1%) in the non-cancer stratum. In the entire cohort, non-retrieved IVC filter placement was not associated with a lower adjusted risk for PE recurrence (HR 0.59, 95% CI 0.30-1.15, P = 0.122), but with an increased adjusted risk for DVT recurrence (HR 2.27, 95% CI 1.43-3.60, P<0.001). In the non-cancer stratum, the non-retrieved IVC filter placement was associated with a decreased risk for PE (HR 0.29, 95% CI 0.09-0.93, P = 0.037), but not with an increased risk for DVT (HR 1.73, 95% CI 0.89-3.38, P = 0.108), while in the active cancer stratum, it was associated with an increased risk for DVT (HR 2.47, 95% CI 1.24-4.91, P = 0.010), but not with a decreased risk for PE (HR 0.82, 95% CI 0.34--1.96, P = 0.650).

CONCLUSIONS

There were some differences in the risk-benefit balance between VTE patients with and without active cancer.

Angiotensin-converting enzyme 2 expression is not induced by the renin-angiotensin system in the lung

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has developed into a pandemic with significant morbidity and mortality. SARS-CoV-2 has been reported to invade lung epithelium via the angiotensin-converting enzyme 2 (ACE2) receptor using its glycosylated cell surface spike protein [1]. ACE2 expression in the heart and kidney is regulated by the renin–angiotensin system (RAS), especially angiotensin II (A-II), which is catalysed from angiotensin I (A-I) by angiotensin-converting enzyme (ACE) [2]. In a cohort study in the early period of the COVID-19 outbreak in Wuhan in China, hypertension was found in 30% of the patients and was identified as the most common comorbidity [3]. It has recently been reported that RAS inhibitors are not associated with the severity of COVID-19 in a meta-analysis that included nine studies comprising 3936 patients with hypertension and COVID-19 [4]. The most serious concerns for the use of RAS inhibitors may be related to their role in development of or exacerbation of COVID-19, as suggested in a recent review by Ingrahamet al. [5]. However, the alteration in ACE2 expression in pulmonary cells has not been studied.

Pulmonary expression of angiotensin-converting enzyme 2, which is a receptor of severe acute respiratory syndrome coronavirus 2, is not regulated by angiotensin II or renin–angiotensin system inhibitors #COVID19https://bit.ly/3fkopuO

Retrograde-angioscopy guided wiring technique in chronic total occlusion lead to successful revascularization

Endovascular therapy (EVT) was performed in two cases with chronic total occlusion (CTO) of superficial femoral artery. In these cases, angioscopy was deployed in the backyard of the CTO lesion from popliteal artery retrogradely, then the guidewire was advanced from antegrade. When the wire crossed the distal of the CTO lesion, the wire penetration was clearly visualized by the retrograde-angioscopy. Therefore, wire crossing of CTO into the distal true lumen was certainly confirmed, and EVT was successful. <Learning objective: Angioscopy-guided endovascular therapy for chronic total occlusion was useful not only to evaluate thrombus and plaque in situ visually, but also to successfully perform guidewire crossing.>.

Predictive value of the coronary artery calcium score and advanced plaque characteristics: Post hoc analysis of the PREDICT registry

BACKGROUND

Whether coronary plaque characteristics assessed in coronary computed tomography angiography (CCTA) in association with the coronary artery calcium score (CACS) have predictive value for coronary events is unclear. We aimed to examine the predictive value of the CACS and plaque characteristics for the occurrence of coronary events.

METHODS

Among 2802 patients who were analyzed in the PREDICT registry, 2083 with suspected coronary artery disease (CAD) were studied using post hoc analysis. High-risk plaques were defined as having ≥2 adverse characteristics, such as low computed tomographic attenuation, positive remodeling, spotty calcification, and napkin-ring sign. An adjudicative composite of coronary events (cardiac death, nonfatal acute coronary syndrome, and coronary revascularization ≥3 months after indexed CCTA) were analyzed.

RESULTS

Seventy-three (3.5%) patients had coronary events and 313 (15.0%) had high-risk plaques. Multivariate Cox proportional hazard analysis showed that high-risk plaques remained an independent predictor of coronary events (adjusted hazard ratio [HR] 1.95, 95% confidence interval [CI] 1.13-3.34, P ​= ​0.0154), as well as the log-transformed CACS (adjusted HR 1.24, 95% CI 1.11-1.39, P ​= ​0.0002) and the presence of obstructive stenosis (adjusted HR 5.63, 95% CI 3.22-10.12, P 0.0001). In subgroup analyses, high-risk plaques were independently predictive only in the low CACS class (<100).

CONCLUSION

This study shows that assessment of adverse features by coronary plaque imaging independently predicts coronary events in patients with suspected CAD and a low CACS. Our findings suggest that the clinical value of high-risk plaques to CACS and stenosis assessment appears marginal.

Determinants and prognostic implications of instantaneous wave-free ratio in patients with mild to intermediate coronary stenosis: Comparison with those of fractional flow reserve

The instantaneous wave-free ratio (iFR) is used for assessing the hemodynamic severity of a lesion, as an alternative to the fractional flow reserve (FFR). We evaluated the relationship between iFR and FFR in detail and the clinical significance of iFR in patients with mild to intermediate coronary artery stenosis. We recruited consecutive 323 patients (421 lesions) with lesions exhibiting 30% to 80% diameter stenosis on angiography in whom FFR and iFR were measured. In the total lesions, mean diameter stenosis was 48.6% ± 9.0%, and physiological significance, defined by FFR of 0.80 or less or by iFR of 0.92 or less, was observed in 32.5% or 33.5%, respectively. Mismatch between iFR and FFR was observed in 18.1% of the lesions. Clinical factors did not predict FFR value; however, gender, diabetes mellitus, aortic stenosis, anemia, high-sensitivity CRP value, and renal function predicted iFR value. In multivariate logistic analysis after adjustment for FFR value, gender (p < 0.001), diabetes mellitus (p = 0.005), aortic stenosis (p = 0.016), high-sensitivity CRP (p < 0.001), and renal function (p = 0.003) were all independent predictors of iFR value. In Kaplan-Meier analysis, the baseline iFR predicted the subsequent major cardiovascular events (MACE) (hazard ratio, 2.40; 95% CI, 1.16–4.93; p = 0.018) and the results of the iFR-guided strategy for predicting rates of MACE and myocardial infarction/revascularization were superior to those of the FFR-guided strategy. In conclusion, significant clinical factors predicted iFR value, which affected the prognostic capacity. The iFR-guided strategy may be superior in patients with mild to intermediate stenosis.

A 50-year history of the health impacts of Westernization on the lifestyle of Japanese Americans: A focus on the Hawaii-Los Angeles-Hiroshima Study

A medical survey of Japanese Americans have been carried out since 1970; in particular, this survey was administered to the Japanese emigrants from Hiroshima (Japan) to Hawaii or Los Angeles (USA) and their offspring. Labeled the Hawaii–Los Angeles–Hiroshima Study, it constituted a long‐term epidemiological study of Japanese Americans who are genetically identical to the native Japanese people, but have experienced rapid and intense Westernization in terms of their lifestyles. The authors have compared the medical survey data procured from two Japanese populations, evincing very disparate lifestyles; that is, the native Japanese inhabitants of Hiroshima (Japan) and Japanese Americans living in Hawaii or Los Angeles (USA). The focus was particularly on differences in the intake of nutrients, the frequency of obesity, the prevalence of metabolic syndrome and diabetes mellitus, and the progression of atherosclerosis. The authors believe that the health effects of the lifestyles of Japanese Americans can predict the imminent health prospects of native Japanese people who adopt Westernized lifestyles in Japan. This review thus summarized the major results accumulated from the Hawaii–Los Angeles–Hiroshima Study over the past 50 years.

Endoplasmic Reticulum Chaperone Calmegin Is Upregulated in Aldosterone-Producing Adenoma and Associates With Aldosterone Production

The endoplasmic reticulum (ER) plays a pivotal role in syntheses of proteins and steroid hormones and regulation of intracellular Ca²⁺ level. We aimed to investigate ER-associated genes in aldosterone-producing adenomas (APAs) and clarify their effect on aldosterone production. Microarray analysis targeting 288 ER-associated genes was conducted using nonfunctioning adrenocortical adenomas (n=5) and APAs (n=19). Immunohistochemistry and quantitative polymerase chain reaction analyses were performed with 13 nonfunctioning adrenocortical adenoma and 48 APA samples. Functional studies were performed with human adrenocortical carcinoma (HAC15) cells, some of which were genetically modified using lentiviruses. The ER chaperone calmegin (CLGN) was the most highly expressed ER-associated gene in APAs relative to nonfunctioning adrenocortical adenomas. Analysis with quantitative polymerase chain reaction revealed CLGN to be 9.5-fold upregulated in APAs relative to nonfunctioning adrenocortical adenomas. There were no differences among different APA genotypes affecting aldosterone production. Immunohistochemistry analysis revealed that CLGN was strongly expressed in APAs and aldosterone-producing cell clusters. Angiotensin II stimulation or KCNJ5 T158A overexpression in HAC15 cells did not affect CLGN mRNA levels. CLGN overexpression in HAC15 cells increased aldosterone levels but did not stimulate CYP11B2 mRNA levels. Pathway and gene ontology analyses using RNA sequencing results showed that tRNA aminoacyl metabolism was the most enriched pathway in CLGN-overexpressing cells. CYP11B2 (aldosterone synthase) and HSD3B2 (3 beta-hydroxysteroid dehydrogenase/delta 5->4-isomerase type 2) protein expression were more abundant in CLGN-overexpressing cells. CLGN knockdown using CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeat-associated 9) method in HAC15 cells that carry the KCNJ5 mutation did not affect aldosterone production. To summarize, CLGN was upregulated and associated with aldosterone production via translational regulation of CYP11B2 in APAs.

Associations of nutrient intakes with glaucoma among Japanese Americans

The aim of this study was to investigate possible associations of nutrient intake on glaucoma in subjects of Japanese descent living in Los Angeles, CA.In this cross-sectional study, 581 Japanese American participants in Los Angeles underwent an interview, fundus photography, comprehensive physical, and blood examinations, along with determining the body mass index status and any confounding factors. CDSketch was used to measure the cup-disc ratio and rim width of each fundus in the retinal photographs. A multivariate logistic regression test with adjustment for confounding factors was used to assess the association between glaucoma and nutrient intake.A total of 61 of 581 participants were diagnosed with glaucoma in this study. Multivariate logistic regression analysis showed that a high intake of iron (odds ratio [OR]: 1.303, P = .004), low intake of vitamin A (OR: 0.365, P = .019), and vegetable fat (OR: 0.957, P = .004) were associated with an increased risk of glaucoma.Current findings showed that high iron intake and low vitamin A and vegetable fat intake appeared to be associated with an increased risk of glaucoma in subjects of Japanese descent living in the Los Angeles populations.

Alteration of gut microbiota by a Westernized lifestyle and its correlation with insulin resistance in non-diabetic Japanese men

AIMS/INTRODUCTION

The severity of insulin resistance is higher in Japanese-American people with American lifestyles than in native Japanese people with Japanese lifestyles. Recently, the role of gut microbiota in the control of host metabolic homeostasis and organ physiology has been recognized. In addition, gut microbiota alterations have been suggested to contribute to pathogenesis of insulin resistance. The principle aim of the present study was to evaluate the impact of a Westernized lifestyle on the gut microbiota of Japanese-Americans versus native Japanese, and its correlation with insulin resistance.

MATERIALS AND METHODS

A total of 14 native Japanese men living in Hiroshima, Japan, and 14 Japanese-American men living in Los Angeles, USA, were included. A 75-g oral glucose tolerance test was carried out for all participants to assess their glucose tolerance, and normal glucose tolerance was observed. We compared the insulin response with oral glucose load, the Matsuda Index, and the composition of the gut microbiota between the native Japanese and Japanese-American men.

RESULTS

Japanese-American men showed higher area under the curve values for serum insulin concentrations during the oral glucose tolerance test and lower Matsuda Index than native Japanese men. Gut microbiota composition of the Japanese-American men was different; in particular, they showed a relatively lower abundance of Odoribacter than native Japanese men. The ratio between relative abundance of Odoribacter and Matsuda Index was positively correlated between the two groups.

CONCLUSIONS

Our findings suggest that Westernized lifestyles alter gut microbiota, and its alteration might induce insulin resistance in non-diabetic Japanese men.

Angiotensin 1-7 suppresses angiotensin II mediated aldosterone production via JAK/STAT signaling inhibition

Angiotensin 1-7 (Ang 1-7), which is a protein cleaved from angiotensin II (A-II), binds to the MAS receptor. Ang 1-7 has been demonstrated to exert protective effects against A-II-mediated cardiac, atherosclerotic, and renal damages. The aims of our study were to demonstrate the inhibitory role of Ang 1-7 in A-II-mediated aldosterone production by interacting with the MAS receptor in human adrenocortical carcinoma (HAC15) cells, and clarify the intracellular signaling mechanisms underlying the inhibition of aldosterone production by Ang 1-7. Ang 1-7 significantly suppressed A-II-stimulated aldosterone production, and partially abrogated A-II-induced upregulation of CYP11B2 expression. Treatment with a selective Ang 1-7 antagonist abrogated Ang 1-7-mediated inhibition of aldosterone production in HAC15 cells. Incubation of A-II-treated HAC15 cells with conditioned medium containing Ang 1-7 was demonstrated to suppress A-II-mediated aldosterone production and CYP11B2 expression. Proteomic analysis showed that Ang 1-7 predominantly inhibited the phosphorylation of JAK-STAT proteins in A-II stimulated HAC15 cells. Treatment of HAC15 cells with a STAT3 inhibitor partially but significantly repressed A-II-mediated aldosterone production by 63.2%. Similarly, treatment with a STAT5 inhibitor significantly abrogated A-II-stimulated aldosterone production in HAC15 cells by 60.7%. In conclusion, we demonstrated that Ang 1-7 negatively regulates A-II-mediated aldosterone production, and the observed inhibition of aldosterone production was associated with JAK/STAT signaling in human adrenal cells. Therefore, activation of Ang 1-7 or stimulation of the MAS receptor, which inhibits aldosterone production, is a promising therapeutic approach for the prevention of cardiovascular events that can directly affect the target organs.

Measurement of midnight ACTH levels is useful for the evaluation of midnight cortisol levels

OBJECTIVE

Elevated midnight cortisol levels induced by non-suppressed ACTH levels may lead to false-positive results for hypercortisolism in patients with adrenal incidentaloma. We investigated whether plasma ACTH-associated high midnight serum cortisol levels are correlated with other endocrinological findings with respect to hypothalamic-pituitaryadrenal function or hypercortisolism status.

METHODS

Two-hundred-forty-six patients with adrenocortical adenoma were evaluated via measurements of midnight ACTH and cortisol levels, a 1-mg dexamethasone suppression test (DST), and a cosyntropin-releasing hormone (CRH) stimulation test. Patients were divided into four groups according to their midnight plasma ACTH levels.

RESULTS

The groups with higher midnight ACTH levels had significantly higher basal ACTH levels. A positive relationship was observed between midnight serum cortisol and serum cortisol in the 1-mg DST for all groups; stronger associations were observed in the group with lower midnight ACTH. In the CRH test, peak, delta, and sigma ACTH had significant inverse relationships with midnight cortisol levels in the lowest and second lowest midnight ACTH groups. Patients with midnight cortisol levels >3.5 μg/dL were further divided into two groups according to whether their midnight plasma ACTH levels were below or above 10.0 pg/mL. There were significantly fewer patients with hypercortisolism in the higher ACTH group; midnight serum cortisol levels were associated with hypercortisolism only in the lower ACTH group.

CONCLUSION

We demonstrated that midnight ACTH-associated cortisol values were not correlated with other endocrinological findings or hypercortisolism state. Measurement of midnight ACTH levels is important, and careful evaluation is needed for patients with higher midnight ACTH levels.

Purkinje Cell Protein 4 Expression Is Associated With DNA Methylation Status in Aldosterone-Producing Adenoma

CONTEXT

Aldosterone production is stimulated by activation of calcium signaling in aldosterone-producing adenomas (APAs), and epigenetic factors such as DNA methylation may be associated with the expression of genes involved in aldosterone regulation.

OBJECTIVE

Our aim was to investigate the DNA methylation of genes related to calcium signaling cascades in APAs and the association of mutations in genes linked to APAs with DNA methylation levels.

METHODS

Nonfunctioning adrenocortical adenoma (n = 12) and APA (n = 35) samples were analyzed. The KCNJ5 T158A mutation was introduced into human adrenocortical cell lines (HAC15 cells) using lentiviral delivery. DNA methylation array analysis was conducted using adrenal tumor samples and HAC15 cells.

RESULTS

The Purkinje cell protein 4 (PCP4) gene was one of the most hypomethylated in APAs. DNA methylation levels in two sites of PCP4 showed a significant inverse correlation with messenger RNA expression in adrenal tumors. Bioinformatics and multiple regression analysis revealed that CCAAT/enhancer binding protein alpha (CEBPA) may bind to the methylation site of the PCP4 promoter. According to chromatin immunoprecipitation assay, CEBPA was bound to the PCP4 hypomethylated region by chromatin immunoprecipitation assay. There were no significant differences in PCP4 methylation levels among APA genotypes. Moreover, KCNJ5 T158A did not influence PCP4 methylation levels in HAC15 cells.

CONCLUSIONS

We showed that the PCP4 promoter was one of the most hypomethylated in APAs and that PCP4 transcription may be associated with demethylation as well as with CEBPA in APAs. KCNJ5 mutations known to result in aldosterone overproduction were not related to PCP4 methylation in either clinical or in vitro studies.

Aberrant G protein-receptor expression is associated with DNA methylation in aldosterone-producing adenoma

This study aimed to evaluate the methylation levels of G protein-coupled receptor (GPCR) related genes and the effects of methylation on mRNA expression levels in aldosterone-producing adenoma (APA). DNA methylation array and transcriptome analysis were applied in non-functioning adrenocortical adenoma (NFA) and APA. We investigated 192 GPCR-related genes and found hypo-methylation in the promoter region of 66 of these genes in APA. An integration study between microarray and methylation analysis revealed that HTR4, MC2R, TACR1, GRM3, and PTGER1 showed hypo-methylation and up-regulation of mRNA in APA. qPCR analysis showed that HTR4 and PTGER1 expression was 9.3-fold and 6.6-fold higher in APAs than in NFAs, respectively, whereas expression of the other genes was not different between the groups. Methylation of HTR4 and PTGER1 at positions -229 and -666 from the transcription start site, respectively, showed a significant inverse correlation with their mRNA levels. Methylation levels were not associated with KCNJ5 or ATP1A1 mutations in human adrenal samples. We demonstrated an increased incidence of CpG island demethylation of GPCR-related gene in APA. The expression of two receptors, HTR4 and PTGER1, showed a strong association with DNA methylation.

Calneuron 1 Increased Ca2+ in the Endoplasmic Reticulum and Aldosterone Production in Aldosterone-Producing Adenoma

Aldosterone production is initiated by angiotensin II stimulation and activation of intracellular Ca²⁺ signaling. In aldosterone-producing adenoma (APA) cells, the activation of intracellular Ca²⁺ signaling is independent of the renin-angiotensin-aldosterone systems. The purpose of our study was to clarify molecular mechanisms of aldosterone production related to Ca²⁺ signaling. Transcriptome analysis revealed that the CALN1 gene encoding calneuron 1 had the strongest correlation with CYP11B2 (aldosterone synthase) among genes encoding Ca²⁺-binding proteins in APA. CALN1 modulation and synthetic or fluorescent compounds were used for functional studies in human adrenocortical carcinoma (HAC15) cells. CALN1 expression was 4.4-fold higher in APAs than nonfunctioning adrenocortical adenomas. CALN1 expression colocalized with CYP11B2 expression as investigated using immunohistochemistry in APA and zona glomerulosa of male rats fed by a low-salt diet. CALN1 expression was detected in the endoplasmic reticulum (ER) by using GFP-fused CALN1, CellLight ER-RFP, and the corresponding antibodies. CALN1-overexpressing HAC15 cells showed increased Ca²⁺ in the ER and cytosol fluorescence-based studies. Aldosterone production was potentiated in HAC15 cells by CALN1 expression, and dose-responsive inhibition with TMB-8 showed that CALN1-mediated Ca²⁺ storage in ER involved sarcoendoplasmic reticulum calcium transport ATPase. The silencing of CALN1 decreased Ca²⁺ in ER, and abrogated angiotensin II- or KCNJ5 T158A-mediated aldosterone production in HAC15 cells. Increased CALN1 expression in APA was associated with elevated Ca²⁺ storage in ER and aldosterone overproduction. Suppression of CALN1 expression prevented angiotensin II- or KCNJ5 T158A-mediated aldosterone production in HAC15 cells, suggesting that CALN1 is a potential therapeutic target for excess aldosterone production.

Hypomethylation of CYP11B2 in Aldosterone-Producing Adenoma

The purpose of this study was to evaluate the DNA methylation levels of steroidogenic enzyme genes in aldosterone-producing adenoma (APA) and the effects of gene mutations in APA on the DNA methylation levels. DNA methylation array analysis was conducted using nonfunctioning adrenocortical adenoma (n=12) and APA (n=35) samples, including some with a KCNJ5 mutation (n=21), an ATP1A1 mutation (n=5), and without the known mutations (n=9). The quantitative polymerase chain reaction assay was performed for the detection of CYP11B2 and CYP11B1 expression levels in nonfunctioning adrenocortical adenoma and APA. We introduced the KCNJ5 T158A mutation using lentivirus delivery in the human adrenocortical 15 cell line, and analyzed the effects of the mutation on DNA methylation levels. We analyzed the 83 presumed DNA methylation sites of steroidogenic enzymes. In APA, we found 7 hypomethylated sites in CYP11B2 and 1 hypomethylated and 6 hypermethylated sites in CYP11B1 There were no differences in the steroidogenic enzymes gene DNA methylation of peripheral leukocytes between nonfunctioning adrenocortical adenoma and APA. No CYP11B2 methylation level was associated with CYP11B2 transcription levels in APA. All methylation sites, except for a CYP11B2 region, showed no difference among APAs with or without gene mutations. Human adrenocortical 15 cells with the KCNJ5 mutation showed no changes in CYP11B2 or CYP11B1 methylation levels compared with control cells. We demonstrated that CYP11B2 in APA was extensively hypomethylated, and CYP11B2 methylation in the region with hypomethylation was not induced by KCNJ5 or ATP1A1 mutations that cause aldosterone overproduction in APA and a KCNJ5 mutation human adrenocortical 15 cells.

Gonadotropin-Releasing Hormone Stimulate Aldosterone Production in a Subset of Aldosterone-Producing Adenoma

We aimed to detect novel genes associated with G protein-coupled receptors (GPCRs) in aldosterone-producing adenoma (APA) and elucidate the mechanisms underlying aldosterone production.Microarray analysis targeting GPCR-associated genes was conducted using APA without known mutations (APA-WT) samples (n = 3) and APA with the KCNJ5 mutation (APA-KCNJ5; n = 3). Since gonadotropin-releasing hormone receptor (GNRHR) was the highest expression in APA-WT by microarray analysis, we investigated the effect of gonadotropin-releasing hormone (GnRH) stimulation on aldosterone production.The quantitative polymerase chain reaction assay results revealed higher GNRHR expression levels in APA-WT samples those in APA-KCNJ5 samples (P < 0.05). LHCGR levels were also significantly elevated in APA-WT samples, and there was a significant and positive correlation between GNRHR and LHCGR expression in all APA samples (r = 0.476, P < 0.05). Patients with APA-WT (n = 9), which showed higher GNRHR and LHCGR levels, had significantly higher GnRH-stimulated aldosterone response than those with APA-KCNJ5 (n = 13) (P < 0.05). Multiple regression analysis revealed that the presence of the KCNJ5 mutation was linked to GNRHR mRNA expression (β = 0.94 and P < 0.01). HAC15 cells with KCNJ5 gene carrying T158A mutation exhibited a significantly lower GNRHR expression than that in control cells (P < 0.05).We clarified increased expression of GNRHR and LHCGR in APA-WT, and the molecular analysis including the receptor expression associated with clinical findings of GnRH stimulation.

Collagen VI deficiency reduces muscle pathology, but does not improve muscle function, in the γ-sarcoglycan-null mouse

Muscular dystrophy is characterized by progressive skeletal muscle weakness and dystrophic muscle exhibits degeneration and regeneration of muscle cells, inflammation and fibrosis. Skeletal muscle fibrosis is an excessive deposition of components of the extracellular matrix including an accumulation of Collagen VI. We hypothesized that a reduction of Collagen VI in a muscular dystrophy model that presents with fibrosis would result in reduced muscle pathology and improved muscle function. To test this hypothesis, we crossed γ-sarcoglycan-null mice, a model of limb-girdle muscular dystrophy type 2C, with a Col6a2-deficient mouse model. We found that the resulting γ-sarcoglycan-null/Col6a2Δex5 mice indeed exhibit reduced muscle pathology compared with γ-sarcoglycan-null mice. Specifically, fewer muscle fibers are degenerating, fiber size varies less, Evans blue dye uptake is reduced and serum creatine kinase levels are lower. Surprisingly, in spite of this reduction in muscle pathology, muscle function is not significantly improved. In fact, grip strength and maximum isometric tetanic force are even lower in γ-sarcoglycan-null/Col6a2Δex5 mice than in γ-sarcoglycan-null mice. In conclusion, our results reveal that Collagen VI-mediated fibrosis contributes to skeletal muscle pathology in γ-sarcoglycan-null mice. Importantly, however, our data also demonstrate that a reduction in skeletal muscle pathology does not necessarily lead to an improvement of skeletal muscle function, and this should be considered in future translational studies.

Genetic characterization and improved genotyping of the dysferlin-deficient mouse strain Dysf (tm1Kcam)

Background

Mouse models of dysferlinopathies are valuable tools with which to investigate the pathomechanisms underlying these diseases and to test novel therapeutic strategies. One such mouse model is the Dysf^tm1Kcam strain, which was generated using a targeting vector to replace a 12-kb region of the dysferlin gene and which features a progressive muscular dystrophy. A prerequisite for successful animal studies using genetic mouse models is an accurate genotyping protocol. Unfortunately, the lack of robustness of currently available genotyping protocols for the Dysf^tm1Kcam mouse has prevented efficient colony management. Initial attempts to improve the genotyping protocol based on the published genomic structure failed. These difficulties led us to analyze the targeted locus of the dysferlin gene of the Dysf^tm1Kcam mouse in greater detail.

Methods

In this study we resequenced and analyzed the targeted locus of the Dysf^tm1Kcam mouse and developed a novel PCR protocol for genotyping.

Results

We found that instead of a deletion, the dysferlin locus in the Dysf^tm1Kcam mouse carries a targeted insertion. This genetic characterization enabled us to establish a reliable method for genotyping of the Dysf^tm1Kcam mouse, and thus has made efficient colony management possible.

Conclusion

Our work will make the Dysf^tm1Kcam mouse model more attractive for animal studies of dysferlinopathies.

Electronic supplementary material

The online version of this article (doi:10.1186/s13395-015-0057-3) contains supplementary material, which is available to authorized users.

Distinct Time Course of the Decrease in Hepatic AMP-Activated Protein Kinase and Akt Phosphorylation in Mice Fed a High Fat Diet

AMP-activated protein kinase (AMPK) plays an important role in insulin resistance, which is characterized by the impairment of the insulin-Akt signaling pathway. However, the time course of the decrease in AMPK and Akt phosphorylation in the liver during the development of obesity and insulin resistance caused by feeding a high fat diet (HFD) remains controversial. Moreover, it is unclear whether the impairment of AMPK and Akt signaling pathways is reversible when changing from a HFD to a standard diet (SD). Male ddY mice were fed the SD or HFD for 3 to 28 days, or fed the HFD for 14 days, followed by the SD for 14 days. We examined the time course of the expression and phosphorylation levels of AMPK and Akt in the liver by immunoblotting. After 3 days of feeding on the HFD, mice gained body weight, resulting in an increased oil red O staining, indicative of hepatic lipid accumulation, and significantly decreased AMPK phosphorylation, in comparison with mice fed the SD. After 14 days on the HFD, systemic insulin resistance occurred and Akt phosphorylation significantly decreased. Subsequently, a change from the HFD to SD for 3 days, after 14 days on the HFD, ameliorated the impairment of AMPK and Akt phosphorylation and systemic insulin resistance. Our findings indicate that AMPK phosphorylation decreases early upon feeding a HFD and emphasizes the importance of prompt lifestyle modification for decreasing the risk of developing diabetes.

Efficacy and safety of insulin degludec in Japanese patients with type 1 and type 2 diabetes: 24-week results from the observational study in routine clinical practice

Aims/Introduction

Insulin degludec, a new long‐acting insulin analog, showed its better glycemic control and reduced risk of hypoglycemia. This is the first prospective observational study that evaluated the efficacy and safety of insulin degludec in routine clinical practice.

Materials and Methods

Japanese patients with type 1 or type 2 diabetes mellitus receiving basal–bolus insulin therapy were switched their basal insulin to degludec, and prospectively observed over a 24‐week course. The Diabetes Therapy‐Related Quality of Life questionnaire was administered before and 12 weeks after switching.

Results

The participants were 80 diabetes patients = (type 1, 44; type 2, 36). In the type 1 group, there was no difference in glycated hemoglobin levels between the pre‐switching and 24‐week measurements (from 62 to 62 mmol/mol, P = 0.768), whereas the daily insulin dose (per kg of bodyweight) decreased significantly (basal, from 0.25 to 0.20 U/kg, P < 0.001; bolus, from 0.40 to 0.37 U/kg, P = 0.001). In the type 2 group, glycated hemoglobin levels decreased after switching (from 60 to 58 mmol/mol, P = 0.028). In the type 1 group, the frequency of hypoglycemia decreased significantly after switching, but not significantly in the type 2 group. Patient satisfaction with the control of hypoglycemia tended to improve in the type 1 group.

Conclusions

Compared with existing long‐acting insulin, degludec can maintain glycemic control at a lower insulin dose and frequency of hypoglycemia in type 1 diabetes, while it can improve glycemic control at an equal insulin dose in type 2 diabetes.

This is first observational prospective study of insulin degludec in routine clinical practice that we evaluated the effect on glycemic control and risk of hypoglycemia in basal‐bolus insulin therapy. We found that insulin degludec can maintain glycemic control at a lower insulin dose and frequency of hypoglycemia in type 1 diabetes, while it can improve glycemic control at equally insulin dose in type 2 diabetes.

These results mean that insulin degludec is of use in routine clinical practice.

Activation of classical brown adipocytes in the adult human perirenal depot is highly correlated with PRDM16-EHMT1 complex expression

Brown fat generates heat to protect against cold and obesity. Adrenergic stimulation activates the thermogenic program of brown adipocytes. Although the bioactivity of brown adipose tissue in adult humans had been assumed to very low, several studies using positron emission tomography-computed tomography (PET-CT) have detected bioactive brown adipose tissue in adult humans under cold exposure. In this study, we collected adipose tissues obtained from the perirenal regions of adult patients with pheochromocytoma (PHEO) or non-functioning adrenal tumors (NF). We demonstrated that perirenal brown adipocytes were activated in adult patients with PHEO. These cells had the molecular characteristics of classical brown fat rather than those of beige/brite fat. Expression of brown adipose tissue markers such as uncoupling protein 1 (UCP1) and cell death-inducing DFFA-like effector A (CIDEA) was highly correlated with the amounts of PRD1-BF-1-RIZ1 homologous domain-containing protein-16 (PRDM16) - euchromatic histone-lysine N-methyltransferase 1 (EHMT1) complex, the key transcriptional switch for brown fat development. These results provide novel insights into the reconstruction of human brown adipocytes and their therapeutic application against obesity and its complications such as type 2 diabetes.

Impact of impaired glucose tolerance on clopidogrel response in patients with coronary artery disease

Although patients with impaired glucose tolerance (IGT) are at increased atherothrombotic risk, it is unclear how antiplatelet drugs act in patients with IGT. The aim of this study was to investigate the pharmacodynamic response to clopidogrel in patients with IGT and insulin resistance (IR). A 75 g oral glucose tolerance test was performed in 65 coronary artery disease (CAD) patients on aspirin and clopidogrel therapy. Platelet function tests were assessed at 3 time-points by light transmittance aggregometry using ADP (5 and 20 μmol/L) stimuli. 30 patients had IGT and 35 normal glucose tolerance (NGT). Among them, 13 patients showed IR. Following ADP stimuli, patients with IGT showed significantly higher maximal platelet aggregation at each time point than those with NGT patients. This resulted in greater high on-treatment platelet reactivity (HPR) rates at each time point in IGT patients (53.3-36.7 vs. 14.3-11.4 %, p < 0.05). A multivariable logistic regression analysis showed that IGT status was the strongest predictor of HPR (odds ratio 7.54, 95 % CI 1.95-29.1, p = 0.003). Following a glucose load, profiles of platelet reactivity varied according to IR status, with minimal changes over time in patients with IR, while there was a significant reduction in the non-IR patients. In aspirin and clopidogrel-treated patients with CAD, IGT is associated with enhanced platelet reactivity and increased rates of HPR compared with NGT patients. These findings suggest the presence of platelet dysfunction in patients with IGT, which may be attributed to the presence of IR.

Clinical utility of low-pressure implantation of drug-eluting stent into very small vessels

BACKGROUND

Although drug-eluting stents (DES) reduce restenosis, the best strategy for DES implantation in small vessels has not been established.

PURPOSE

We investigated the clinical usefulness of low-pressure implantation of a 2.5-mm DES for small vessels less than 2.5mm in diameter.

METHODS

In 118 patients, a 2.5-mm DES was implanted for small vessels less than 2.5mm in diameter between 2007 and 2009 in our hospital. The patients were divided into two groups by initial deployment pressure: low-pressure (LP; n=46) and nominal-pressure (NP; n=72).

RESULTS

Patients with impaired glucose tolerance were more frequent (p=0.02) and the target vessel diameter was significantly smaller (p=0.01) in the LP group than in the NP group. A smaller minimum lumen diameter (MLD) was obtained (LP: 2.22±0.27mm vs. NP: 2.34±0.26mm, p=0.02) after DES implantation with a smaller balloon-to-artery ratio (p=0.03) in the LP group. However, at mid-term follow-up (7.7±3.9 months), MLD (p=0.55) and the binary restenosis rate (LP: 2.6% vs. NP: 11.1%, p=0.12) were not significantly different between the LP and NP groups. Furthermore, by Kaplan-Meier analysis, the incidence of major adverse cardiac events was not different between the groups during the long-term follow-up (32.4±8.6 months).

CONCLUSION

The present study indicates that low-pressure implantation of 2.5-mm DES for very small vessels may be feasible with regard to short- and long-term clinical outcomes.

Quantitative myocardial perfusion analysis using multi-row detector CT in acute myocardial infarction

OBJECTIVE

To assess the feasibility of quantitative myocardial perfusion imaging (MPI) in acute myocardial infarction (AMI), using multi-row detector CT (MDCT) with a model-based deconvolution method. DESIGN, SETTING, PATIENTS AND INTERVENTIONS: Fifteen normal subjects with normal coronary arteries and 26 patients with AMI after reperfusion therapy underwent MPI with MDCT. Perfusion parameters: tissue blood flow (TBF), tissue blood volume (TBV) and mean transit time (MTT) were obtained and compared with clinical parameters, angiography and single-photon emission CT (SPECT) data. Furthermore, the MPI data were compared with data from myocardial magnetic resonance (MR) in 10 subjects.

RESULTS

The TBF and TBV of infarcted myocardium were significantly lower than those of non-infarcted areas (TBF, 51.96±19.42 vs 108.84±13.29 ml/100 g/min, p<0.01; TBV, 4.47±2.23 vs 9.79±2.58 ml/100 g, p<0.01). The MTT of infarcted areas did not differ from that of non-infarcted areas. The defect areas on TBV colour maps were significantly associated with peak creatine kinase level, QRS score and SPECT defect score. The ratio of TBF or TBV in the epicardial to endocardial side was significantly higher in infarct myocardium with good collateral circulation than in myocardium with poor/no collateral circulation (p<0.01 for both). The TBF measurements with CT- and MR-MPI were in good agreement by linear regression analysis (R=0.55, p<0.01).

CONCLUSIONS

This study demonstrated that MDCT perfusion imaging with deconvolution analysis could quantitatively detect myocardial perfusion abnormalities in patients with AMI and may provide the basis for the non-invasive and quantitative assessment of myocardial infarction.

A common disease-associated missense mutation in alpha-sarcoglycan fails to cause muscular dystrophy in mice

Limb-girdle muscular dystrophy type 2D (LGMD2D) is caused by autosomal recessive mutations in the alpha-sarcoglycan gene. An R77C substitution is the most prevalent cause of the disease, leading to disruption of the sarcoglycan-sarcospan complex. To model this common mutation, we generated knock-in mice with an H77C substitution in alpha-sarcoglycan. The floxed neomycin (Neo)-cassette retained at the targeted H77C alpha-sarcoglycan locus caused a loss of alpha-sarcoglycan expression, resulting in muscular dystrophy in homozygotes, whereas Cre-mediated deletion of the floxed Neo-cassette led to recovered H77C alpha-sarcoglycan expression. Contrary to expectations, mice homozygous for the H77C-encoding allele expressed both this mutant alpha-sarcoglycan and the other components of the sarcoglycan-sarcospan complex in striated muscle, and did not develop muscular dystrophy. Accordingly, conditional rescued expression of the H77C protein in striated muscle of the alpha-sarcoglycan-deficient mice prevented the disease. Adding to the case that the behavior of mutant alpha-sarcoglycan is different between humans and mice, mutant human R77C alpha-sarcoglycan restored the expression of the sarcoglycan-sarcospan complex when introduced by adenoviral vector into the skeletal muscle of previously created alpha-sarcoglycan null mice. These findings indicate that the alpha-sarcoglycan with the most frequent missense mutation in LGMD2D is correctly processed, is transported to the sarcolemma, and is fully functional in mouse muscle. Our study presents an unexpected difference in the behavior of a missense-mutated protein in mice versus human patients, and emphasizes the need to understand species-specific protein quality control systems.

OC29 is preferentially expressed in the presumptive sensory organ region of the otocyst

The mammalian inner ear derives from the otocyst. Molecular mechanisms underlying inner ear development are largely unknown. We have isolated a secreted molecule, OC29, from a rat otocyst cDNA library by the signal sequence trap method. OC29 was revealed to be a rat homologue of human WFIKKN. OC29 is preferentially expressed in the developing inner ear and the dorsal neural tube. In the inner ear, the expression of OC29 is first detectable at embryonic day 11.5 (E11.5), broadly in the dorsolateral region of the otocyst, which gives rise to the vestibular organ. At E12.5, the expression of OC29 becomes restricted to the presumptive sensory region, mainly to the BMP4-positive presumptive cristae, and expression becomes reduced at later stages. These results suggest that OC29 may have a role in the early development of the inner ear sensory organ, particularly in the formation of the cristae of the semicircular canals.

Stem cell-derived neural stem/progenitor cell supporting factor is an autocrine/paracrine survival factor for adult neural stem/progenitor cells

Recent evidence suggests that adult neural stem/progenitor cells (ANSCs) secrete autocrine/paracrine factors and that these intrinsic factors are involved in the maintenance of adult neurogenesis. We identified a novel secretory molecule, stem cell-derived neural stem/progenitor cell supporting factor (SDNSF), from adult hippocampal neural stem/progenitor cells by using the signal sequence trap method. The expression of SDNSF in adult central nervous system was localized to hippocampus including dentate gyrus, where the neurogenesis persists throughout life. In induced neurogenesis status seen in ischemically treated hippocampus, the expression of SDNSF was up-regulated. As functional aspects, SDNSF protein provided a dose-dependent survival effect for ANSC following basic fibroblast growth factor 2 (FGF-2) withdrawal. ANSCs treated by SDNSF also retain self-renewal potential and multipotency in the absence of FGF-2. However, SDNSF did not have mitogenic activity, nor was it a cofactor that promoted the mitogenic effects of FGF-2. These data suggested an important role of SDNSF as an autocrine/paracrine factor in maintaining stem cell potential and lifelong neurogenesis in adult central nervous system.

Role of cytokines in autoimmune myocarditis and cardiomyopathy

Cellular as well as humoral autoimmune responses are critically associated with the pathogenesis and progression of myocarditis and cardiomyopathy. Cytokines appear to play critical roles in accentuating or regulating autoimmune mechanisms in these disorders. However, depending on the triggers of autoimmune responses against the heart, such as viral or parasitic infections and experimental immunization with cardiac myosin, the effect of each cytokine on autoimmune myocardial disease may vary. Cytokines may represent new therapeutic targets in the treatment and prevention of autoimmunity-mediated myocarditis and cardiomyopathy, though the etiology and variability in the type of autoimmune responses should be taken into account in the development of cytokine/anti-cytokine treatment of these disorders.

Fibulin-5/DANCE is essential for elastogenesis in vivo

The elastic fibre system has a principal role in the structure and function of various types of organs that require elasticity, such as large arteries, lung and skin. Although elastic fibres are known to be composed of microfibril proteins (for example, fibrillins and latent transforming growth factor (TGF)-beta-binding proteins) and polymerized elastin, the mechanism of their assembly and development is not well understood. Here we report that fibulin-5 (also known as DANCE), a recently discovered integrin ligand, is an essential determinant of elastic fibre organization. fibulin-5-/- mice generated by gene targeting exhibit a severely disorganized elastic fibre system throughout the body. fibulin-5-/- mice survive to adulthood, but have a tortuous aorta with loss of compliance, severe emphysema, and loose skin (cutis laxa). These tissues contain fragmented elastin without an increase of elastase activity, indicating defective development of elastic fibres. Fibulin-5 interacts directly with elastic fibres in vitro, and serves as a ligand for cell surface integrins alphavbeta3, alphavbeta5 and alpha9beta1 through its amino-terminal domain. Thus, fibulin-5 may provide anchorage of elastic fibres to cells, thereby acting to stabilize and organize elastic fibres in the skin, lung and vasculature.

ESDN, a novel neuropilin-like membrane protein cloned from vascular cells with the longest secretory signal sequence among eukaryotes, is up-regulated after vascular injury

A novel cDNA has been isolated from primary culture of human coronary arterial cells by a signal sequence trap method, and designated ESDN (endothelial and smooth muscle cell-derived neuropilin-like molecule). ESDN is a type-I transmembrane protein with the longest cleavable secretory signal sequence among eukaryotes. ESDN contains a CUB domain and a coagulation factor V/VIII homology domain, which reminds us of the structure of neuropilins. ESDN also harbors an LCCL domain, which is shared by Limulus factor C and Coch. Mouse and rat counterparts were also identified revealing >84% amino acid identity with human ESDN. The human ESDN gene was mapped between D3S1552 and D3S1271. Northern blot analysis showed that ESDN mRNA was expressed in various tissues; particularly highly expressed in cultured vascular smooth muscle cells. The ESDN expression was up-regulated in platelet-derived growth factor-BB-stimulated vascular smooth muscle cells in vitro and neointima of the balloon-injured carotid artery in vivo. Overexpression of ESDN in 293T cells suppressed their bromodeoxyuridine uptake. In addition, ESDN protein was strongly expressed in nerve bundles in rodents. Thus, ESDN is considered to play a role in regulation of vascular cell growth and may have a wide variety of functions in other tissues including the nervous system, like neuropilins.

DANCE, a novel secreted RGD protein expressed in developing, atherosclerotic, and balloon-injured arteries

We have identified and characterized mouse, rat, and human cDNAs that encode a novel secreted protein of 448 amino acids named DANCE (developmental arteries and neural crest epidermal growth factor (EGF)-like). DANCE contains six calcium-binding EGF-like domains, one of which includes an RGD motif. Overexpression studies of recombinant DANCE protein document that DANCE is a secreted 66-kDa protein. DANCE and recently described protein S1-5 comprise a new EGF-like protein family. The human DANCE gene was mapped at chromosome 14q32.1. DANCE mRNA is mainly expressed in heart, ovary, and colon in adult human tissues. Expression profile analysis by in situ hybridization revealed prominent DANCE expression in developing arteries. DANCE is also expressed in neural crest cell derivatives, endocardial cushion tissue, and several other mesenchymal tissues. In adult vessels, DANCE expression is largely diminished but is reinduced in balloon-injured vessels and atherosclerotic lesions, notably in intimal vascular smooth muscle cells and endothelial cells that lose their ability to proliferate in late stage of injury. DANCE protein was shown to promote adhesion of endothelial cells through interaction of integrins and the RGD motif of DANCE. DANCE is thus a novel vascular ligand for integrin receptors and may play a role in vascular development and remodeling.

Molecular-pathological analysis of a patient with three synchronous squamous cell carcinomas in the aerodigestive tract

A case of synchronous squamous cell carcinomas in the soft palate, larynx and esophagus is reported, along with findings of molecular-pathological analysis. A biopsy sample from the aryngeal carcinoma revealed well differentiated squamous cell carcinoma harboring two point mutations at codons 144 and 148 of the p53 gene but not at codon 299, and more than 50% of the cancer cells showed accumulation of p53 protein immunohistochemically. The esophageal tumor, which was moderately differentiated squamous cell carcinoma, showed immunoreactivity for p53 within the nuclei of 25-50% of cancer cells with a missense mutation at codon 299 but not at codon 144 or 148. This cancer also showed immunoreactivity for transforming growth factor alpha. On the other hand, the poorly differentiated squamous cell carcinoma in the soft palate showed negative immunoreactivity for p53 and no point mutation in exons 5 to 8 of the gene. These results suggest that the three synchronous squamous cell carcinomas arose as independent events.

Distribution of neurokinin A-like and neurokinin B-like immunoreactivity in human peripheral tissues

Using specific radioimmunoassay and immunocytochemistry for neurokinin A (NKA) and neurokinin B (NKB), distribution and localization of the two peptides in human peripheral tissues were studied. Both NKA-like immunoreactivity (NKA-LI) and NKB-like immunoreactivity (NKB-LI) were present in the walls of the gut and gall bladder and in the pancreas. In the gut, the values for NKA-LI were 0.56-35.73 pmol/g wet weight, while those in pancreas and gall bladder were 0.64-0.68 and 0.36 pmol/g wet weight, respectively. The values of NKB-LI were 0.45-2.66 pmol/g wet weight in the gut, 0.93-1.65 pmol/g wet weight in the pancreas, and 0.30 pmol/g wet weight in the gall bladder. The immunocytochemical reactivity to both peptides was localized to ganglia of the submucosal and myenteric nerve plexuses in the gut wall, and to neurons in the muscle layer and mucosa of the gut wall. Weak but positive NKA-LI appeared in nerve cells of the pancreas, while NKB-LI was not detectable in the pancreas. Conversely, in the gall bladder wall, NKA-LI was undetectable while a very faint NKB-LI was found in the muscle layer. The localization of NKA corresponded closely to that of NKB in the tissues although the relative concentrations of the peptides varied from organ to organ.

Preventive effect of cimetidine on chronic erosive gastritis induced by taurocholate in rats

We studied the preventive effect of cimetidine at the microscopic level on chronic erosive gastritis induced experimentally by 6-months of administration of drinking water containing 5 mmol/l of the sodium salt of taurocholic acid (TCA) in rats. The chronic erosive gastritis was characterized by mucosal erosions, reduction of mucosal thickness and reduction in the number of parietal cells per unit area, infiltration of inflammatory cells which were mainly lymphocytes and plasmocytes, and proliferation of collagenous fibers in the gastric mucosa. A standard meal including cimetidine 0.4 and 0.8%, which was administered ad libitum with TCA, reduced the total length of erosions, normalized the mucosal thickness and the number of parietal cells, and reduced inflammatory cell infiltration in the gastric mucosa. However, cimetidine did not show any effect on the proliferation of collagenous fibers in the interstitial space of the mucosa. The doses administered were 400 mg/kg/day and 800 mg/kg/day for 6 months. Cimetidine, thus, had a preventive effect on experimental chronic erosive gastritis in rats.

Analysis of cellular immunity in patients with Graves' disease

Graves' disease has attracted considerable attention as an autoimmune disease. In this study, cellular immunity in patients with this disease was assessed. Specifically examined was the lymphocyte response to mitogens, Interleukin-2 (IL-2) production from peripheral blood mononuclear cells (PBMCs) and the percentage of lymphocyte subsets. No significant difference was observed in the lymphocyte response to phytohemagglutinin (PHA), concanavalin A (Con A) and poke-weed mitogen (PWM) between untreated patients with Graves' disease and healthy people. IL-2 production in untreated patients, however, was significantly greater than that of healthy people. While a significant decrease was observed in the percentage of CD8+ cells in untreated patients, no difference was found in the percentage of CD5+, CD4+ and HLA-DR+ cells between them and healthy people. It is thought that the enhancement of IL-2 production by PBMCs and the decrease in the percentage of CD8+ cells (cytotoxic/suppressor cell) are associated with abnormalities in the immune system.

Distribution and localization of neurokinin A-like immunoreactivity and neurokinin B-like immunoreactivity in rat peripheral tissue

Using specific radioimmunoassays and immunocytochemistry for neurokinin A (NKA) and neurokinin B (NKB), distribution and localization of these peptides in rat peripheral tissues were studied. NKA-like immunoreactivity (NKA-LI) was present in highest levels of 15.7-23.9 pmol/g wet wt. and NKB-like immunoreactivity (NKB-LI) was in levels of 0.33-0.67 pmol/g wet wt., throughout the gastrointestinal tract involving stomach, duodenum, jejunum, ileum and colon. Immunocytochemical analysis of gastrointestinal tract revealed that NKA-LI and NKB-LI localized in ganglia of both the submucosal and myenteric plexuses as well as varicose neurons in the mucosa and the muscle layer of the small and large intestine. On the other hand, high levels of NKB-LI were observed in oesophagus (0.83 +/- 0.08 pmol/g wet wt.), adrenal (1.02 +/- 0.21), head of pancreas (0.73 +/- 0.06) and kidney (0.98 +/- 0.05). The present study shows the difference of localization of NKA-LI and NKB-LI in peripheral tissues and suggests that NKB may have some physiological role differing from that of NKA in peripheral tissues.

Further study of mucosal repair by sofalcone in experimental gastritis

The effect of sofalcone on the glandular structure and cell proliferation in the gastric mucosa of rats with gastritis induced by the administration of sodium taurocholate (TCA) for 6 months was examined by histoquantitative analysis and [3H]thymidine autoradiography. Morphometric observation revealed that, with TCA treatment, mucosal thickness, parietal cell mass, and the ratios of the length of the glandular portion/total length of the gastric gland were decreased in both the fundic and pyloric glands. Inflammatory cell infiltration and collagenous fiber proliferation were present in the gastric mucosa following TCA and indicated the presence of atrophic gastritis. These atrophic changes and inflammatory cell infiltration were reversed by a 3 week administration of sofalcone. Cellular proliferative activity assessed by the labeling indices of the gastric mucosa increased in TCA-induced gastritis in rats. The administration of sofalcone to rats with TCA-induced gastritis significantly increased labeling indices, particularly in the pyloric glands. From these results, it appears that sofalcone stimulates the compensatory increase in proliferative activity of generative cells, which then may become available to heal the gastritis.

Detection of soluble tumor-associated antigens in sera and effusions using novel monoclonal antibodies, KL-3 and KL-6, against lung adenocarcinoma

Two novel monoclonal antibodies, KL-3 (IgM) and KL-6 (IgG1), which can detect soluble antigens in sera and effusions (molecular weights greater than 1,000 K) were produced against human pulmonary adenocarcinoma VMRC-LCR cells. KL-3 and KL-6 antibodies reacted with asialo- and sialo-carbohydrate antigenic determinants, respectively. Both carbohydrate epitopes appear, from competitive inhibition studies, to be different from Lex, Ley, sialyl Lea and sialyl Lexi which were recognized with FH2, AH6, NS19-9 and FH6 antibodies, respectively. Using an enzyme linked immunosorbent assay, elevated KL-6 antigen levels were frequently observed in the sera of patients with lung adenocarcinoma [52% (17/33)], pancreatic cancer [44% (4/9)] and breast cancer [40% (8/20)], but infrequently in the sera of patients with lung squamous cell carcinoma [18% (4/22)], lung small cell carcinoma [8% (1/13)], gastric cancer [0% (0/19)], colorectal cancer [0% (0/8)] and hepatocellular cancer [13% (1/8)]. The levels and positive rates of serum KL-6 antigen increased with the progression of clinical stage of lung adenocarcinoma. In pleural effusions, the prevalences of lung adenocarcinoma cases with elevated levels of KL-3 and KL-6 antigens were 76% (13/17) and 82% (14/17), respectively. These monoclonal antibodies can define novel soluble antigens in sera and effusions which could be useful in tumor diagnoses and for monitoring tumor progression.