Combined pituitary hormone deficiency harboring CHD7 gene missense mutation without CHARGE syndrome: a case report

BACKGROUND

Heterozygous loss-of-function mutations in the chromodomain helicase DNA-binding protein 7 (CHD7) gene cause CHARGE syndrome characterized by various congenital anomalies. A majority of patients with CHARGE syndrome present with congenital hypogonadotropic hypogonadism (HH), and combined pituitary hormone deficiency (CPHD) can also be present. Whereas CHD7 mutations have been identified in some patients with isolated HH without a diagnosis of CHARGE syndrome, it remains unclear whether CHD7 mutations can be identified in patients with CPHD who do not fulfill the criteria for CHARGE syndrome.

CASE PRESENTATION

A 33-year-old woman was admitted to our hospital. She had primary amenorrhea and was at Tanner stage 2 for both pubic hair and breast development. She was diagnosed with CPHD (HH, growth hormone deficiency, and central hypothyroidism), and a heterozygous rare missense mutation (c.6745G > A, p.Asp2249Asn) in the CHD7 gene was identified. Our conservation analysis and numerous in silico analyses suggested that this mutation had pathogenic potential. She had mild intellectual disability, a minor feature of CHARGE syndrome, but did not fulfill the criteria for CHARGE syndrome.

CONCLUSIONS

We report a rare case of CPHD harboring CHD7 mutation without CHARGE syndrome. This case provides valuable insights into phenotypes caused by CHD7 mutations. CHD7 mutations can have a continuous phenotypic spectrum depending on the severity of hypopituitarism and CHARGE features. Therefore, we would like to propose a novel concept of CHD7-associated syndrome.

Exogenous insulin antibody syndrome in a patient with diabetes secondary to total pancreatectomy

Exogenous insulin can induce insulin antibodies that have a low affinity/high binding capacity. Similar to what is observed in insulin autoimmune syndrome, these insulin antibodies can cause fasting hypoglycemia and postprandial hyperglycemia, a phenomenon known as "exogenous insulin antibody syndrome" (EIAS). Cases of EIAS in patients with type 1 and type 2 diabetes have been sporadically reported, mainly in Asia. However, there has been no report on EIAS in patients with diabetes secondary to total pancreatectomy treated with insulin analogs. A 74-year-old man with diabetes after total pancreatectomy had been treated with continuous subcutaneous insulin infusion using an insulin analog, lispro, and developed recurrent early morning hypoglycemia even after discontinuation of nocturnal basal insulin. His fasting serum lispro level was high even approximately 9 h after the last lispro dose. He had a high titer (72.7%) of insulin antibodies, and a Scatchard analysis revealed low affinity/high binding capacity. These findings suggested that the patient's recurrent early morning hypoglycemia was associated with insulin antibodies against lispro, and we, therefore, switched from lispro to another insulin analog, glulisine. His hypoglycemia improved, accompanied by a dramatic decrease in his insulin antibodies and serum glulisine levels. Early morning hypoglycemia in patients with diabetes secondary to total pancreatectomy may often be explained by high glycemic variability, malnutrition, and/or glucagon deficiency. However, in cases of recurrent early morning hypoglycemia, EIAS should be considered as a potential differential diagnosis.

Metformin-associated Lactic Acidosis with Hypoglycemia during the COVID-19 Pandemic

Metformin-associated lactic acidosis (MALA) is an extremely rare but life-threatening adverse effect of metformin treatment. The lifestyle changes associated with the coronavirus disease 2019 (COVID-19) pandemic may increase the potential risk of MALA development in patients with diabetes. We herein report a 64-year-old Japanese man taking a small dose of metformin who presented with MALA accompanied by hypoglycemia secondary to increased alcohol consumption triggered by lifestyle changes during the pandemic. Physicians should prescribe metformin judiciously to prevent MALA development and pay close attention to lifestyle changes in patients at risk for MALA during the COVID-19 pandemic.

Medium-term Influence of the Coronavirus Disease 2019 Pandemic on Patients with Diabetes: A Single-center Cross-sectional Study

Objective This study evaluated the lifestyle changes in patients with diabetes and their independent associations with glycemic and body weight control. In addition, the correlation between changes in mental health and lifestyles was evaluated. Methods This single-center cross-sectional study included 340 patients with diabetes who periodically visited our department. Changes in dietary habits, activities of daily living, and mental health before and during approximately six months after the onset of the coronavirus disease 2019 (COVID-19) pandemic were evaluated using a questionnaire, including the International Physical Activity Questionnaire-Short Form. Results Approximately 20%, 30%, and over 50% of patients had worsened dietary habits, decreased activities of daily living, and deteriorated mental health, respectively. A multiple regression analysis showed that irregular meal timing was significantly associated with change in HbA1c (β=0.328, p=0.001), and decreased walking time was significantly associated with changes in body weight (β=-0.245, p=0.025). The change in fear and anxiety was positively associated with changes in meal timing regularity (r=0.129, p=0.019) and carbohydrate consumption (r=0.127, p=0.021). Subsequently, the change in depressed mood was positively associated with changes in carbohydrate (r=0.142, p=0.010) and alcohol (r=0.161, p=0.037) consumption, and the change in psychological stress was positively associated with changes in carbohydrates (r=0.183, p=0.001) and snack (r=0.151, p=0.008) consumption as well as sedentary time (r=0.158, p=0.004). Conclusion The COVID-19 pandemic has had a considerable medium-term impact on the lifestyle and mental health of patients with diabetes. Lifestyle changes were associated with glycemic and body weight control, and mental health changes were associated with lifestyle changes. These findings may provide important information on diabetes care during the pandemic.

Coexistence of renin-independent aldosterone secretion and multiple endocrine neoplasia type 1 within a family

Primary aldosteronism (PA) is a state of renin-independent aldosterone secretion that can range from subclinical to overt. Some normotensive individuals for whom PA screening is not routinely recommended are reported to fulfill the loading test criterion used for the diagnosis of PA. Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterized by the development of various endocrine tumors. Cases of PA associated with MEN1 have been reported; however, there has been no previous report on renin-independent aldosterone secretion within a family with MEN1. Herein, we present the case of a normotensive family presenting with both MEN1 and renin-independent aldosterone secretion. A 49-year-old man was admitted to our hospital for PA evaluation owing to the plasma aldosterone concentration/plasma renin activity ratio being greater than the screening cut-off value; the patient was normotensive. The patient had a history of left nephrectomy and adrenalectomy for left renal carcinoma and adrenal tumor at the age of 39 years. Subsequently, he was diagnosed with MEN1 concurrent with primary hyperparathyroidism, insulinoma, and novel MEN1 gene mutations (c.655-5_655-4insC, and c.818delC). The loading tests for PA confirmation, including saline infusion, and furosemide upright and captopril challenge tests yielded positive findings, confirming a case of renin-independent aldosterone secretion. The patient’s mother, brother, and sister were also genetically or clinically diagnosed with MEN1. All of them were also normotensive and confirmed to have renin-independent aldosterone secretion. The coexistence of renin-independent aldosterone secretion and MEN1 within this family suggests a relationship between the two entities.

A Japanese patient with a 2p25.3 terminal deletion presented with early-onset obesity, intellectual disability and diabetes mellitus: A case report

2p25.3 deletion syndrome is a rare genetic disorder that accompanies various phenotypic features, including early‐onset obesity and intellectual disability. Here, we report the first Japanese case of this deletion associated with severe obesity and diabetes mellitus. Microarray‐based comparative genomic hybridization analysis identified a 3.1‐Mb deletion of distal chromosome band 2p25.3, which was suspected as de novo. The patient also presented bilateral cataracts and adolescent‐onset muscular weakness of the upper limbs, both of which were uncommon in previously reported cases. It is possible that these symptoms are also important clinical features suggestive of this syndrome.

Hypoglycemia during the Concomitant Use of Repaglinide and Clopidogrel in an Elderly Patient with Type 2 Diabetes and Severe Renal Insufficiency

Hypoglycemia should be avoided when treating patients with diabetes. Repaglinide is an insulin secretagogue with a low hypoglycemic risk because of its rapid- and short-acting effects. However, its blood concentration has been reported to increase in combination with clopidogrel, an antiplatelet drug, and in patients with severe renal insufficiency. We herein report an elderly patient with type 2 diabetes mellitus and severe renal insufficiency who received repaglinide and hypoglycemia three days after starting clopidogrel. The concomitant use of repaglinide and clopidogrel can lead to hypoglycemia, especially in patients with severe renal insufficiency.

Activation of invariant natural killer T cells ameliorates doxorubicin-induced cardiotoxicity in mice

Objective

Doxorubicin (DOX) is one of the most important anticancer agents and widely used to treat cancers but clinical utility of DOX is limited for its dose-dependent cardiotoxicity. The precise mechanism of DOX-induced cardiotoxicity is still not fully understood but it has been reported that cardiac inflammation is involved in the cardiotoxicity. Invariant natural killer T (iNKT) cells, a unique subset of T lymphocytes that recognize glycolipid antigens and secrete a large amount of both Th1 and Th2 cytokines on activation, have been shown to play crucial roles in the regulation of immune responses. However, it remains unclear whether iNKT cells are involved in DOX-induced cardiotoxicity.

Methods and results

Male C57BL/6J mice were administered DOX (20mg/kg body weight; n=28) or vehicle (Vehicle; n=6). DOX-administered mice were further divided into 2 groups; those treated with α-galactosylceramide (αGC, 0.1μg/g body weight; DOX-αGC; n=14), which specifically activates iNKT cells, or those treated with PBS (DOX-PBS; n=14) by intraperitoneal injections (twice; 4 days before and 3 days after DOX administration).An echocardiography conducted at 14 days after DOX/Vehicle administration revealed that LV fractional shortening was significantly reduced in the DOX-PBS compared to the Vehicle (49.3±0.8% vs. 59.2±1.7%, P<0.05), and this decrease was completely attenuated in the DOX-αGC (57.7±1.3%, P<0.05 vs. DOX-PBS)without affecting LV end-diastolic diameter. Flow cytometric analysis revealed that the ratio of iNKT cells to mononuclear cells infiltrated into the heart tissue was significantly increased in the DOX+αGC compared to the Vehicle and the DOX+PBS (1.00±0.09% vs. 0.54±0.09% and 0.71±0.07%, P<0.05). Immuno-histochemistry revealed that the infiltration number of Iba1+macrophages in the heart tissue was significantly elevated in the DOX+αGC compared to the Vehicle and the DOX+PBS (55.4±3.2 cells/mm2 vs. 21.7±2.0 cells/mm2 and 37.5±5.9 cells/mm2, P<0.05) The ratio of fibrosis area to the heart tissue was markedly higher in the DOX-PBS than in Vehicle (4.3±0.5% vs. 2.2±0.1%, P<0.05), and this increase was completely attenuated in the DOX-αGC (2.8±0.1%, P<0.05 vs.DOX-PBS).Real-time PCR analysis revealed that mRNA expressions of M2 macrophage markers (Arginase 1 and Retnla) and IL-4 were significantly enhanced in the DOX+αGC compared to the DOX+PBS (Arginase 1: 2.5±0.4 vs. 1.6±0.3 [relative ratio to the Vehicle], P=0.08; Retnla: 2.4±0.5 vs. 1.1±0.2 [relative ratio to the Vehicle], P<0.05; IL-4: 1.0±0.3 vs. 8.94±2.8 [relative ratio to the DOX+PBS], P<0.05), while those of M1 macrophage markers (iNOS and MCP-1) did not change among all groups.

Conclusions

Activation of iNKT cells ameliorates DOX-induced cardiotoxicity in mice via enhanced M2 macrophage polarization with the upregulation of IL-4 and reducing cardiac fibrosis. iNKT cell activation can be a novel preventive strategy against DOX-induced cardiotoxicity.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Japan Agency for Medical Research and Development (18lm0203001j0002) and JSPS KAKENHI (18K15834).

A disintegrin and metalloproteinase 12 prevents heart failure by regulating cardiac hypertrophy and fibrosis

A disintegrin and metalloproteinase (ADAM)12 is considered to promote cardiac dysfunction based on the finding that a small-molecule ADAM12 inhibitor, KB-R7785, ameliorated cardiac function in a transverse aortic constriction (TAC) model by inhibiting the proteolytic activation of heparin-binding-EGF signaling. However, this compound has poor selectivity for ADAM12, and the role of ADAM12 in cardiac dysfunction has not yet been investigated using genetic loss-of-function mice. We revealed that ADAM12 knockout mice showed significantly more advanced cardiac hypertrophy and higher mortality rates than wild-type mice 4 wk after TAC surgery. An ADAM12 deficiency resulted in significantly more expanded cardiac fibrosis accompanied by increased collagen-related gene expression in failing hearts. The results of a genome-wide transcriptional analysis suggested a strongly enhanced focal adhesion- and fibrosis-related signaling pathway in ADAM12 knockout hearts. The loss of ADAM12 increased the abundance of the integrinβ1 subunit and transforming growth factor (TGF)-β receptor types I and III, and this was followed by the phosphorylation of focal adhesion kinase, Akt, mammalian target of rapamycin, ERK, and Smad2/3 in the heart, which resulted in cardiac dysfunction. The present results revealed that the loss of ADAM12 enhanced focal adhesion and canonical TGF-β signaling by regulating the abundance of the integrinβ1 and TGF-β receptors.NEW & NOTEWORTHY In contrast to a long-believed cardio-damaging role of a disintegrin and metalloproteinase (ADAM)12, cardiac hypertrophy was more severe, cardiac function was lower, and mortality was higher in ADAM12 knockout mice than in wild-type mice after transverse aortic constriction surgery. The loss of ADAM12 enhanced focal adhesion- and fibrosis-related signaling pathways in the heart, which may compromise cardiac function. These results provide insights for the development of novel therapeutics that target ADAM12 to treat heart failure.

P1623Activation of invariant natural killer T cells by alpha-galactosylceramide ameliorates doxorubicin-induced cardiotoxicity in mice

Objective

Doxorubicin (DOX) is an effective antineoplastic agent commonly used to treat many types of cancer but its clinical use is limited because of cardiotoxicity, which might proceed to irreversible cardiac dysfunction in a dose-dependent manner. The precise mechanism of DOX-induced cardiotoxicity is still not fully elucidated but it has been reported that cardiac inflammation is involved in the cardiotoxicity. Invariant natural killer T (iNKT) cells, a unique subset of T lymphocytes that recognize glycolipid antigens and secrete a large amount of Th1 and Th2 cytokines on activation, have been shown to play crucial roles in the regulation of immune responses. However, it remains unclear whether iNKT cells are involved in DOX-induced cardiotoxicity.

Methods and results

Male C57BL/6J mice were administered DOX (20mg/kg body weight single intraperitoneal injection; n=28) or vehicle (Vehicle; n=6). DOX-administered mice were further divided into 2 groups; α-galactosylceramide (αGC, 0.1μg/g body weight twice intraperitoneal injection; DOX-αGC; n=14), which specifically activates iNKT cells, or phosphate-buffered saline alone (PBS; DOX-PBS; n=14) 4 days before and 3 days after DOX administration. Survival rate at 14 days after DOX/Vehicle administration was significantly lower in DOX-PBS than in Vehicle (71% vs. 100%, P<0.05), and this decrease was completely attenuated in DOX-αGC (100%, P<0.05 vs. DOX-PBS). Echocardiography at 14 days after DOX/Vehicle administration revealed that left ventricular (LV) fractional shortening was significantly reduced in DOX-PBS compared to Vehicle (49.3±0.8% vs. 59.2±1.7%, P<0.05), and this decrease was completely attenuated in DOX-αGC (57.7±1.3%, P<0.05 vs. DOX-PBS) without affecting LV end-diastolic diameter. Picro-sirius red staining revealed that the ratio of fibrosis area to the cardiac tissue was markedly higher in DOX-PBS than in Vehicle (4.3±0.5% vs. 2.2±0.1%, P<0.05), and this increase was completely attenuated in DOX-αGC (2.8±0.1%, P<0.05 vs. DOX-PBS). Real-time PCR analysis revealed that mRNA expression of anti-inflammatory Th2 cytokine IL-4 was enhanced by 7.9-folds in DOX-αGC compared to DOX-PBS, though the difference did not reach statistically significance (P=0.09).

Conclusions

Activation of iNKT cells by αGC ameliorates DOX-induced cardiotoxicity in mice via up-regulation of anti-inflammatory IL-4 and reducing cardiac fibrosis. iNKT cell activation may be a novel therapeutic strategy against DOX-induced cardiotoxicity.

Acknowledgement/Funding

Japan Agency for Medical Research and Development (18lm0203001j0002) and JSPS KAKENHI (18K15834)

Impact of glycosylphosphatidylinositol-specific phospholipase D on hepatic diacylglycerol accumulation, steatosis, and insulin resistance in diet-induced obesity

Glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) is an enzyme that specifically cleaves GPI anchors. Previous human studies suggested the relationship of GPI-PLD to insulin resistance, type 1 and type 2 diabetes, and nonalcoholic fatty liver disease (NAFLD). However, the biological roles of GPI-PLD have not been elucidated. Here, we hypothesized that GPI-PLD impacted on lipid and glucose metabolism, especially in the liver. GPI-PLD mRNA was most highly expressed in the liver, and the hepatic mRNA level and circulating concentration of GPI-PLD were significantly augmented in diabetic mice. To investigate in vivo functions of GPI-PLD, we generated GPI-PLD knockout (GP-KO) mice. Mice lacking GPI-PLD exhibited the amelioration of glucose intolerance and hepatic steatosis under high-fat and high-sucrose diet. Furthermore, diacylglycerol (DAG) content was significantly decreased, and PKCε activity was suppressed in the livers of GP-KO mice. In vitro knockdown and overexpression experiments of GPI-PLD using rat primary hepatocytes showed the GPI-PLD-dependent regulation of intracellular DAG content. Finally, serum GPI-PLD levels were strongly and independently associated with serum alanine transaminase (R = 0.37, P = 0.0006) and triglyceride (R = 0.34, P = 0.001) levels in male subjects with metabolic syndrome. In conclusion, upregulation of hepatic GPI-PLD in diabetic conditions leads to DAG accumulation in the liver by shedding GPI anchors intracellularly, which may play a causal role in impaired hepatic insulin signaling and the progression of NAFLD.

Adiponectin/T-cadherin system enhances exosome biogenesis and decreases cellular ceramides by exosomal release

Adiponectin, an adipocyte-derived circulating protein, accumulates in vasculature, heart, and skeletal muscles through interaction with a unique glycosylphosphatidylinositol-anchored cadherin, T-cadherin. Recent studies have demonstrated that such accumulation is essential for adiponectin-mediated cardiovascular protection. Here, we demonstrate that the adiponectin/T-cadherin system enhances exosome biogenesis and secretion, leading to the decrease of cellular ceramides. Adiponectin accumulated inside multivesicular bodies, the site of exosome generation, in cultured cells and in vivo aorta, and also in exosomes in conditioned media and in blood, together with T-cadherin. The systemic level of exosomes in blood was significantly affected by adiponectin or T-cadherin in vivo. Adiponectin increased exosome biogenesis from the cells, dependently on T-cadherin, but not on AdipoR1 or AdipoR2. Such enhancement of exosome release accompanied the reduction of cellular ceramides through ceramide efflux in exosomes. Consistently, the ceramide reduction by adiponectin was found in aortas of WT mice treated with angiotensin II, but not in T-cadherin-knockout mice. Our findings provide insights into adiponectin/T-cadherin-mediated organ protection through exosome biogenesis and secretion.

Association of Epicardial, Visceral, and Subcutaneous Fat With Cardiometabolic Diseases

BACKGROUND

Excess of visceral fat is a central factor in the pathogenesis of metabolic syndrome (MetS) and atherosclerosis. However, little is known about how much epicardial fat affects cardiometabolic disorders in comparison with visceral or subcutaneous fat.Methods and Results:Participants suspected as having angina pectoris underwent cardiac computed tomography (CT) imaging. Of them, 374 subjects were analyzed the association of clinical characteristics and CT-based fat distribution measured as epicardial fat volume (EFV), visceral fat area (VFA), and subcutaneous fat area (SFA). EFV was highly associated with VFA (R=0.58). Serum adiponectin was significantly decreased in high VFA subjects (VFA ≥100 cm²) and was also reduced in the high EFV group (EFV ≥80 cm³). Among the low VFA groups, the numbers of subjects with diabetes and coronary atherosclerosis were increased in high EFV group. Among the low EFV groups, the numbers of subjects with diabetes, hyperuricemia, and coronary atherosclerosis were increased among the high VFA subjects. In an age-, sex-, and body mass index (BMI)-adjusted model, EFV was associated with dyslipidemia and MetS, and VFA was significantly associated with hypertension, dyslipidemia, MetS, and coronary atherosclerosis, while SFA was not related with coronary risks and atherosclerosis.

CONCLUSIONS

Epicardial fat accumulation may be a risk for coronary atherosclerosis in subjects without visceral fat accumulation. Visceral fat is the strongest risk for cardiometabolic diseases among the 3 types of fat depot.

The unique prodomain of T-cadherin plays a key role in adiponectin binding with the essential extracellular cadherin repeats 1 and 2

Adiponectin, an adipocyte-derived circulating protein, accumulates in the heart, vascular endothelium, and skeletal muscles through an interaction with T-cadherin (T-cad), a unique glycosylphosphatidylinositol-anchored cadherin. Recent studies have suggested that this interaction is essential for adiponectin-mediated cardiovascular protection. However, the precise protein-protein interaction between adiponectin and T-cad remains poorly characterized. Using ELISA-based and surface plasmon analyses, we report here that T-cad fused with IgG Fc as a fusion tag by replacing its glycosylphosphatidylinositol-anchor specifically bound both hexameric and larger multimeric adiponectin with a dissociation constant of ∼1.0 nm and without any contribution from other cellular or serum factors. The extracellular T-cad repeats 1 and 2 were critical for the observed adiponectin binding, which is required for classical cadherin-mediated cell-to-cell adhesion. Moreover, the 130-kDa prodomain-bearing T-cad, uniquely expressed on the cell surface among members of the cadherin family and predominantly increased by adiponectin, contributed significantly to adiponectin binding. Inhibition of prodomain-processing by a prohormone convertase inhibitor increased 130-kDa T-cad levels and also enhanced adiponectin binding to endothelial cells both by more preferential cell-surface localization and by higher adiponectin-binding affinity of 130-kDa T-cad relative to 100-kDa T-cad. The preferential cell-surface localization of 130-kDa T-cad relative to 100-kDa T-cad was also observed in normal mice aorta in vivo In conclusion, our study shows that a unique key feature of the T-cad prodomain is its involvement in binding of the T-cad repeats 1 and 2 to adiponectin and also demonstrates that adiponectin positively regulates T-cad abundance.

Oncogenic signaling by Kit tyrosine kinase occurs selectively on the Golgi apparatus in gastrointestinal stromal tumors

Gastrointestinal stromal tumors (GISTs) are caused by gain-of-function mutations in the Kit receptor tyrosine kinase. Most primary GIST patients respond to the Kit inhibitor imatinib, but this drug often becomes ineffective because of secondary mutations in the Kit kinase domain. The characteristic intracellular accumulation of imatinib-sensitive and -resistant Kit protein is well documented, but its relationship to oncogenic signaling remains unknown. Here, we show that in cancer tissue from primary GIST patients as well as in cell lines, mutant Kit accumulates on the Golgi apparatus, whereas normal Kit localizes to the plasma membrane (PM). In imatinib-resistant GIST with a secondary Kit mutation, Kit localizes predominantly on the Golgi apparatus. Both imatinib-sensitive and imatinib-resistant Kit (Kit(mut)) become fully auto-phosphorylated only on the Golgi and only if in a complex-glycosylated form. Kit(mut) accumulates on the Golgi during the early secretory pathway, but not after endocytosis. The aberrant kinase activity of Kit(mut) prevents its export from the Golgi to the PM. Furthermore, Kit(mut) on the Golgi signals and activates the phosphatidylinositol 3-kinase–Akt (PI3K–Akt) pathway, signal transducer and activator of transcription 5 (STAT5), and the Mek–Erk pathway. Blocking the biosynthetic transport of Kit(mut) to the Golgi from the endoplasmic reticulum inhibits oncogenic signaling. PM localization of Kit(mut) is not required for its signaling. Activation of Src-family tyrosine kinases on the Golgi is essential for oncogenic Kit signaling. These results suggest that the Golgi apparatus serves as a platform for oncogenic Kit signaling. Our study demonstrates that Kit(mut)’s pathogenicity is related to its mis-localization, and may offer a new strategy for treating imatinib-resistant GISTs.

Adiponectin association with T-cadherin protects against neointima proliferation and atherosclerosis

Adiponectin, an adipocyte-derived protein abundant in the circulation, is thought to be protective against atherosclerosis. However, it is not fully understood how the association of adiponectin with vascular cells and its antiatherogenic effect are connected. In this study, T-cadherin was essential for accumulation of adiponectin in the neointima and atherosclerotic plaque lesions, and the adiponectin-T-cadherin association protected against vascular injury. In the apolipoprotein E-knockout (ApoE-KO) mice, adiponectin and T-cadherin colocalized on endothelial cells and synthetic smooth muscle cells in the aortic intima. Notably, aortic adiponectin protein disappeared in T-cadherin/ApoE double-knockout (Tcad/ApoE-DKO) mice with significant elevation of blood adiponectin concentration. Furthermore, in Tcad/ApoE-DKO mice, carotid artery ligation resulted in a significant increase of neointimal thickness compared with ApoE-KO mice. Finally, on a high-cholesterol diet, Tcad/ApoE-DKO mice increased atherosclerotic plaque formation, despite a 5-fold increase in plasma adiponectin level compared with that in ApoE-KO mice. In vitro, knockdown of T-cadherin from human aortic smooth muscle cells (HASMCs) with synthetic phenotype significantly reduced adiponectin accumulation on HASMCs and negated the inhibitory effect of adiponectin on proinflammatory change. Collective evidence showed that adiponectin accumulates in the vasculature via T-cadherin, and the adiponectin-T-cadherin association plays a protective role against neointimal and atherosclerotic plaque formations.-Fujishima, Y., Maeda, N., Matsuda, K., Masuda, S., Mori, T., Fukuda, S., Sekimoto, R., Yamaoka, M., Obata, Y., Kita, S., Nishizawa, H., Funahashi, T., Ranscht, B., Shimomura, I. Adiponectin association with T-cadherin protects against neointima proliferation and atherosclerosis.

Impact of visceral fat on gene expression profile in peripheral blood cells in obese Japanese subjects

Background

Visceral fat plays a central role in the development of metabolic syndrome and atherosclerotic cardiovascular diseases. The association of visceral fat accumulation with cardio-metabolic diseases has been reported, but the impact of visceral fat on the gene expression profile in peripheral blood cells remains to be determined. The aim of this study was to determine the effects of visceral fat area (VFA) and subcutaneous fat area (SFA) on the gene expression profile in peripheral blood cells of obese subjects.

Methods

All 17 enrolled subjects were hospitalized to receive diet therapy for obesity (defined as body mass index, BMI, greater than 25 kg/m²). VFA and SFA were measured at the umbilical level by computed tomography (CT). Blood samples were subjected to gene expression profile analysis by using SurePrint G3 Human GE Microarray 8 × 60 k ver. 2.0. The correlation between various clinical parameters, including VFA and SFA, and peripheral blood gene expression levels was analyzed.

Results

Among the 17 subjects, 12 had normal glucose tolerance or borderline diabetes, and 5 were diagnosed with type 2 diabetes without medications [glycated hemoglobin (HbA1c); 6.3 ± 1.3%]. The mean BMI, VFA, and SFA were 30.0 ± 5.5 kg/m², 177 ± 67 and 245 ± 131 cm², respectively. Interestingly, VFA altered the expression of 1354 genes, including up-regulation of 307 and down-regulation of 1047, under the statistical environment that the parametric false discovery rate (FDR) was less than 0.1. However, no significant effects were noted for SFA or BMI. Gene ontology analysis showed higher prevalence of VFA-associated genes than that of SFA-associated genes, among the genes associated with inflammation, oxidative stress, immune response, lipid metabolism, and glucose metabolism.

Conclusions

Accumulation of visceral fat, but not subcutaneous fat, has a significant impact on the gene expression profile in peripheral blood cells in obese Japanese subjects.

Serum adiponectin levels predict the risk of coronary heart disease in Japanese patients with type 2 diabetes

AIMS/INTRODUCTION

An inverse association between adiponectin and coronary heart disease (CHD) has been found in Caucasians, but it is uncertain whether this association can be extrapolated to the East Asian population. The present study aimed to investigate whether serum adiponectin levels can predict CHD in Japanese patients with type 2 diabetes as observed in Caucasians.

MATERIALS AND METHODS

This longitudinal study included 504 patients with type 2 diabetes (342 men and 162 women) who were admitted to Sumitomo Hospital between July 2005 and December 2006. We used Cox proportional hazard analysis to estimate the hazard ratio (HR) of CHD associated with serum adiponectin levels at baseline.

RESULTS

During a median follow up of 5.7 years (2177 person-years), 40 participants had new CHD and 10 had recurrent CHD. After multivariate adjustment, the highest compared with the lowest quartile of serum adiponectin levels had a significantly reduced risk of CHD (hazard ratio [HR] 0.35; 95% confidence interval [CI] 0.13-0.94; P = 0.017). The multivariate adjusted HR for the risk of CHD according to a doubling of adiponectin at baseline was 0.61 (95% CI 0.39-0.97; P = 0.037).

CONCLUSIONS

High serum adiponectin levels are significantly associated with a lower risk of CHD in Japanese patients with type 2 diabetes. This association is independent of other well-known CHD risk factors.

Relationship between serum adiponectin levels and age in healthy subjects and patients with type 2 diabetes

OBJECTIVE

Serum adiponectin levels are affected by gender, body fat mass, several pathological factors or therapeutic interventions and it might be also affected by age. This study aimed to investigate the relationship between serum adiponectin levels and age in several physiological states.

DESIGN, PATIENTS AND MEASUREMENTS

The study was carried out in 21 100 healthy subjects (12 363 men and 8737 women) and 1833 patients with type 2 diabetes (1233 men and 600 women). Physical and demographic characteristics were recorded, and blood samples were collected to measure serum adiponectin levels. Using these data, we determined the relationships between serum adiponectin levels and various parameters, including age.

RESULTS

Serum adiponectin levels increased with increasing age of healthy subjects and in patients with diabetes, in both men and women. Serum adiponectin levels were positively correlated with age in healthy subjects and patients with diabetes, in both men and women. In stepwise multiple regression analysis with serum adiponectin levels as the dependent variable and physiological characteristics as explanatory variables, age was significantly and independently associated with serum adiponectin levels in each of these groups of subjects.

CONCLUSIONS

Serum adiponectin levels are significantly and positively associated with age in healthy subjects and in patients with diabetes. This association is independent of renal function, body fat status, glucose metabolism and lipid profiles.

Scale-up Effect in Internal Mixers

In the development of a new polymer and a new compound, mixing equipment plays an important role. However, the properties of a compound tend to vary depending on the size and shape of the equipment used and a means to obtain the same compound by a small scale laboratory mixer as the one obtained by a large scale mixer has been longed for a long time.

As a rubber compound is characterized by the physical properties, they are affected both by the dimensions and shape of the equipment and the mixing conditions. Recently, we developed a laboratory mixer generally following the designs of FH Banbury with exchangeable rotors and mixing chamber blocks which enable us to investigate the influences of the shape of equipment as well as the mixing conditions.

In analysing rubber mixing, we found that the following factors should be taken into account, that is, unit-work which is the applied energy to the unit volume of the material during mixing, Mooney viscosity of the compound, bound rubber which is the amount of polymer unextractable from the compound by a solvent, and weight average molecular weight of polymer extractable by a solvent. If the values of the four factors are close enough for the two compounds obtained by different mixers of different size and shape, one may regard them as the same compounds. Furthermore, we experimentally measured the four factors for the compounds of typical formulations of three species of commercially available rubbers, that is, styrene butadiene rubber, ethylene propylene rubber and butadiene, and expressed the values of the factors as functions of mixing conditions and the parameters of rotor shapes by means of multiple regression analysis. Among the rotor parameters, the following showed significant effects: tip clearance, tip width, total bulkiness and wing overlap ratio. As for the mixing conditions, mixing time, rotor speed and mixing temperature were dominant.

Using the functions obtained by the above mentioned method for the laboratory scale mixer, we tried to find the combinations of rotor shapes and mixing conditions that reproduced the compound mixed by large scale mixers. The optimum parameters of a laboratory mixer for the reproduction of the mixing of an industrial mixer were found to be larger rotor tip clearance, larger rotor tip width, larger wing overlap ratio, higher mixing temperature, and higher rotor speed than those of proportionally reduced dimensions and comparable conditions.

Relationship between Rotor Designs in an Internal Mixer and Physical Properties of Mixed Rubber Compounds

Internal mixers are commonly used for rubber compounding in industry. However, the relations among the designs of equipments, mixing conditions and the properties of the resulting compound are little known. In this paper we tried to reveal some manners of the relations concentrating, particularly, on rotor designs. A specially designed internal mixer (Banbury type) was developed. A number of double winged rotors of various shapes and replaceable mixing chambers were prepared. In developing the equipment, eight parameters were taken into consideration concerning the shape of rotors, that is, lengths, twist angles and overlap ratio of the wings, width and clearance at the rotor tip, angles of flow-in and flow-out at the gap area and total bulkiness of the rotor. Measured properties concerning mixing are: unit work, Mooney viscosity of dumped compound, the amount of bound rubber, weight average molecular weight of the extracted portion of the compound, and peaks in a torque curve, i.e., values of first peak torque and second peak time. In order to estimate the degree of influences of the design parameters mentioned above and mixing conditions, each measured properties were expressed as functions of these parameters by means of multiple regression analysis.

Association of adiponectin with blood pressure in healthy people

OBJECTIVE

With the increasing prevalence of diseases related to obesity, metabolic syndrome and its key player adiponectin are now attracting considerable attention. Hypoadiponectinaemia is reported to be a risk factor for hypertension and associated with endothelial dysfunction, which is closely related to complications of obesity such as hypertension. As there is limited information regarding serum adiponectin levels in normotensive people, we undertook the large-scale study to determine the association of adiponectin with blood pressure (BP) in mainly normotensive people.

DESIGN, PATIENTS AND MEASUREMENTS

In 21 100 Japanese adults (12 363 men and 8737 women) who had no apparent diseases, we examined the relationship between the serum adiponectin concentration and BP by performing a questionnaire survey, physical measurements and measurement of laboratory parameters including the serum adiponectin level.

RESULTS

Subjects with hypoadiponectinaemia had higher systolic and diastolic BPs as already reported. And interestingly, subjects with higher adiponectin had lower systolic and diastolic BP. According to linear regression analysis, adiponectin showed a significant negative correlation with systolic and diastolic BP independently of the other variables. Analysis of covariance according to adiponectin quintiles showed that systolic and diastolic BP in highest adiponectin quintile was significantly lower than in other quintiles.

CONCLUSIONS

This study revealed that there were significant trends toward lower systolic and diastolic BP with higher adiponectin not only in hypertensive people but also in normotensive people.

Resolution of gelatinous bone marrow transformation following hormone replacement therapy in a patient with primary insufficiency of the adrenal and thyroid glands

A 59-year-old man with recurrent oral cancer presented with severe pancytopenia, hyponatremia and hypoglycemia. Endocrine testing showed a partial primary adrenal insufficiency and primary hypothyroidism. The bone marrow biopsy showed a gelatinous transformation with hypocellularity and fat atrophy. His pancytopenia, hyponatremia and hypoglycemia resolved following treatment with corticosteroids and thyroid hormone replacement therapy. The follow-up bone marrow biopsy demonstrated a resolution of the gelatinous transformation. This case is a rare example of a patient with a primary insufficiency of the adrenal and thyroid glands that is associated with gelatinous bone marrow transformation (GMT). The GMT was resolved through the administration of corticosteroids and thyroid hormone replacement therapy.

Serum adiponectin level is not only decreased in metabolic syndrome but also in borderline metabolic abnormalities

Objective:

Along with the increasing prevalence of obesity and related diseases, particularly atherosclerotic diseases, metabolic syndrome (MetS) is now a common and major public health issue in many countries around the world. Adiponectin, a protein secreted by the adipose tissue, has become recognized as a key player in the development of MetS. These days, not only MetS but also borderline metabolic/physiological abnormalities, such as impaired fasting glucose, high normal blood pressure and high normal plasma cholesterol, have been reported to be risk factors for atherosclerotic disease. Therefore, we undertook this study to determine the relationship between adiponectin and borderline metabolic/physiological abnormalities, as well as MetS.

Design:

A cross-sectional study performed from April 2007 to November 2009.

Subjects:

In 16 892 Japanese adults (10 008 men and 6884 women), we examined the relationship between the serum adiponectin concentration and borderline metabolic/physiological abnormalities or MetS by a questionnaire survey about medical treatment, body size measurement and measurement of laboratory parameters including the serum adiponectin concentration.

Results:

Adiponectin showed a significant negative correlation with the number of MetS components. In subjects without overt diabetes mellitus, hypertension or dyslipidemia, the adiponectin concentration also showed a significant negative correlation with the number of borderline metabolic abnormalities.

Conclusion:

The decrease of circulating adiponectin may start before the development of diabetes mellitus, hypertension, dyslipidemia or MetS. Adiponectin is an important biomarker for reflecting the adverse influence of visceral fat in persons with MetS, and also in these subclinical states.

Scattered radiation from dental metallic crowns in head and neck radiotherapy

We aimed to estimate the scattered radiation from dental metallic crowns during head and neck radiotherapy by irradiating a jaw phantom with external photon beams. The phantom was composed of a dental metallic plate and hydroxyapatite embedded in polymethyl methacrylate. We used radiochromic film measurement and Monte Carlo simulation to calculate the radiation dose and dose distribution inside the phantom. To estimate dose variations in scattered radiation under different clinical situations, we altered the incident energy, field size, plate thickness, plate depth and plate material. The simulation results indicated that the dose at the incident side of the metallic dental plate was approximately 140% of that without the plate. The differences between dose distributions calculated with the radiation treatment-planning system (TPS) algorithms and the data simulation, except around the dental metallic plate, were 3% for a 4 MV photon beam. Therefore, we should carefully consider the dose distribution around dental metallic crowns determined by a TPS.

Glomerulocystic kidney disease in an adult with enlarged kidneys: a case report and review of the literature

We report the case of a 31-year-old male with enlarged kidneys and glomerulocystic kidney disease (GCKD). The patient had no family history of renal disease or other diseases. On initial presentation he complained of poor eyesight, and hypertensive retinopathy and elevated serum creatinine (5.0 mg/dl) were found at that time. Renal biopsy showed cystic dilatation of Bowman's capsule and atrophy of the glomerular tuft. Thus, an adult case of sporadic GCKD was diagnosed. Based on previous reports, kidney size in patients with adult type GCKD varies from small to large. Our patient's kidneys are the largest ever reported (right kidney was 22 cm×10 cm, left kidney was 19 cm×10 cm). A review of the literature dealing with sporadic adult GCKD suggested that it is difficult to diagnose this disease early in its course.

Long-term efficacy of trilostane for Cushing's syndrome due to adrenocorticotropin-independent bilateral macronodular adrenocortical hyperplasia

A 66-year-old man with Cushing's syndrome due to adrenocorticotropin-independent bilateral macronodular adrenocortical hyperplasia (AIMAH) was treated for 7 years with trilostane, a 3β-hydroxysteroid dehydrogenase inhibitor. Administration of trilostane reduced the serum cortisol level to around the upper limit of normal for 7 years, and symptoms of excessive glucocorticoid production (such as moon face and obesity) were gradually improved. On the other hand, the size of both adrenal glands gradually increased despite treatment with trilostane. Though trilostane therapy could not prevent adrenal growth, it did suppress cortisol secretion over the long term, so it might be a reasonable option for AIMAH in addition to adrenalectomy.

The effect of gantry and collimator angles on leaf limited velocity and position in dynamic multileaf collimator intensity-modulated radiation therapy

The purpose of the study is to evaluate the limiting velocity (LV) of a multileaf collimator and the leaf position in various collimator and gantry angles. Both leading leaves and trailing leaves began to move with a constant acceleration from 0 to 4 cm s(-1). When the beam hold occurred, the leaf velocity was defined as the leaf LV. Dynamic irradiation was performed at eight gantry angles of every 45 degrees with three different collimator angles. The analysis of the LV and the leaf position was performed with a log file from a leaf motion controller. The mean LVs for Varian Clinac 21EX (21EX) ranged from 2.51 to 3.10 cm s(-1). The mean LVs for Clinac 600C ranged from 2.91 to 3.12 cm s(-1). When only central 5 mm leaves of 21EX moved, LVs were significantly higher than those when all 60 pairs of leaf moved, while the leaf position inconsistencies of the two accelerators were within 1 mm at the leaf velocities from 0.5 to 2.0 cm s(-1). It was recognized that the LV was affected by gravity. This measurement method can be utilized as routine quality assurance for a dynamic multileaf collimator (DMLC) is and easily reproducible.

Four-dimensional quantitative analysis of the gait of mutant mice using coarse-grained motion capture

To analyze an abnormal gait pattern in mutant mice (Hugger), we conducted coarse-grained motion capture. Using a simple retroreflective marker-based approach, we could detect high-resolution mutant-specific gait patterns. The phenotypic gait patterns are caused by extreme vertical motion of limbs, revealing inefficient motor functions. To elucidate the inefficiency, we developed a musculoskeletal computer model of the mouse hindlimb based on X-ray CT data. By integrating motion data with the model, we determined mutant-specific musculotendon lengths, suggesting that three major muscles were involved in the abnormal gait. This approach worked well on laboratory mice, which were putatively too small to be motion capture subjects. Motion capture technology was originally developed for human study, and our approach may help fill neuroscience gaps between mouse and human behavioral phenotypes.

JDP2 suppresses adipocyte differentiation by regulating histone acetylation

Among the events that control cellular differentiation, the acetylation of histones plays a critical role in the regulation of transcription and the modification of chromatin. Jun dimerization protein 2 (JDP2), a member of the AP-1 family, is an inhibitor of such acetylation and contributes to the maintenance of chromatin structure. In an examination of Jdp2 'knock-out' (KO) mice, we observed elevated numbers of white adipocytes and significant accumulation of lipid in the adipose tissue in sections of scapulae. In addition, mouse embryo fibroblasts (MEFs) from Jdp2 KO mice were more susceptible to adipocyte differentiation in response to hormonal induction and members of the CCAAT/enhancer-binding proteins (C/EBP) gene family were expressed at levels higher than MEFs from wild-type mice. Furthermore, JDP2 inhibited both the acetylation of histone H3 in the promoter of the gene for C/EBPdelta and transcription from this promoter. Our data indicate that JDP2 plays a key role as a repressor of adipocyte differentiation by regulating the expression of the gene for C/EBPdelta via inhibition of histone acetylation.

Paternal dual barrier by Ifg2-H19 and Dlk1-Gtl2 to parthenogenesis in mice

The functional difference between the maternal and paternal genome, which is characterized by epigenetic modifications during gametogenesis, that is genomic imprinting, prevents mammalian embryos from parthenogenesis. Genomic imprinting leads to nonequivalent expression of imprinted genes from the maternal and paternal alleles. However, our research showed that alteration of maternal imprinting by oocyte reconstruction using nongrowing oocytes together with deletion of the H19 gene, provides appropriate expression of maternally imprinted genes. Here we discuss that further alteration of paternally imprinted gene expressions at chromosomes 7 and 12 allows the ng/fg parthenogenetic embryos to develop to term, suggesting that the paternal contribution is obligatory for the descendant.

254 DEVELOPMENTAL COMPETENCE OF MOUSE OOCYTES AFTER IN VITRO GROWTH, NUCLEAR TRANSFER, AND IN VITRO FERTILIZATION

Long-term effects of in vitro maturation of oocytes and in vitro culture of fertilized eggs have been reported in ruminants, mice, and humans. However, effects of in vitro oocyte growth are unknown. Although a large number of non-growing oocytes can be a gamete resource, very few oocytes ever acquire competence to support full-term development after in vitro growth. The objective of the study was to evaluate different culture conditions and the long-term effects of in vitro oocyte growth on the production of offspring. Oocytes of newborn, 10-day-old, and adult BDF1 (C57BL/6N � DBA2) mice were cultured for 22, 11, and 1 day(s), respectively. The results showed that alpha-MEM medium was superior to Waymouth medium in oocyte growth (68.6 � 3.87 �m vs. 61.7 � 3.26 �m, respectively; P &lt; 0.001), and in maintenance of follicular integrity (69% vs. 30%; P &lt; 0.001) when non-growing oocytes from newborn mice were cultured. However, oocytes grown in vitro were incompetent to support meiotic maturation by themselves in the case of either the 22-day culture of oocytes from newborn mice (1/59 in alpha-MEM vs. 1/65 in Waymouth) or the 11-day culture of oocytes from 10-day-old mice (51/140 in alpha-MEM vs. 2/157 in Waymouth), and none of them developed to the blastocyst stage. Subsequently, to examine the nucleic competence of oocytes grown in vitro, serial nuclear transfers were carried out. Karyoplasts from oocytes grown in vitro using alpha-MEM were fused with the GV oocytes grown in vivo after enucleation. The reconstituted oocytes were cultured in alpha-MEM. After 14 h, MII chromosomes of the reconstituted oocytes were transferred into the enucleated and ovulated MII oocytes in order to provide cytoplasmic competency. The results showed that when the donor oocytes attained a diameter of e60 �m, the reconstituted oocytes could develop into pups at extremely high rates (30-41%) after in vitro fertilization (IVF) and embryo transfer in the case of either the 22-day culture of oocytes from newborn mice (7/17) or the 11-day culture of oocytes from 10-day-old mice (25/77). A significant difference was not observed in the competence to develop to term of the reconstituted oocytes when compared with that of the oocytes reconstituted from the control GV (25/52; P &gt; 0.05). When the donor oocytes attained a diameter of 50–60 �m, the reconstituted oocytes also could develop into pups (7/33); however, their efficiency was significantly reduced when compared with that of the reconstituted oocytes from the control GV (P &lt; 0.05). On the other hand, the weight of the offspring depended on the duration of culture, and offspring from non-growing oocytes (1.48 � 0.17 g) were heavier than those of the IVF control (1.25 � 0.14 g; P &lt; 0.05). In conclusion, we have demonstrated that using a nuclear transfer technique combined with in vitro growth of oocytes was sufficient to produce functional oocytes, and long-term culture for oocyte growth did not affect the nucleic ability of oocytes to develop to term; however, fetal growth may be susceptible to the duration of culture.

358 MICROINSEMINATION USING MALE GERM CELLS FROM EPIDIDYMIDES AND TESTES STORED IN FREEZERS WITHOUT CRYOPROTECTANT

Cryopreservation of male germ cells is a strategy for the conservation of species and strains valuable to biomedical researchers. However, to minimize damage that may occur during freezing and thawing, complex cryopreservation protocols that have been optimized for the stage and species of the male germ cell are usually employed. This study was undertaken to see whether mouse male germ cells could be safely cryopreserved for later use by freezing the whole epididymides and testes without cryoprotectant. Furthermore, we examined whether frozen male germ cells maintained their fertilization ability after international transportation on dry ice. Epididymides and testes were collected from sexually mature male ICR and C57BL/6Cr mice and placed in polypropylene cryotubes. The cryotubes were frozen at -80�C with or without a freezing container, or were plunged directly into liquid nitrogen (LN2). They were stored at -80�C or in LN2 from between one week and one year. Epididymides and testes were thawed by placing the cryotubes in a water bath at room temperature. B6D2F1 and C57BL/6Cr oocytes were microinseminated with either epididymal and testicular spermatozoa or round spermatids. After embryo transfer into pseudopregnant females, normal pups were obtained irrespective of the method of cryopreservation and cell type used. However, their birth rates (2-33%) were lower than those of our conventional microinsemination using fresh sperm or spermatids (20-60%). For transportation experiments, testes were collected from C57BL/6J mice and placed in a cryotube. The cryotubes were frozen at -80�C in a freezing container. On the day of transportation, the cryotubes were placed in a polystyrene foam case filled with dry ice and were transported from Harwell (UK) to Tsukuba (Japan) by air and land. After three days, the samples were delivered to the recipient facility and were stored at -80�C until use (about 1 month). After thawing and collection of spermatogenic cells, C57BL/6J oocytes were microinseminated with either testicular spermatozoa or elongated spermatids. After embryo transfer, 24 (34% per transfer) and 8 (16%) offspring, respectively, were obtained from the two groups. These results indicate that mouse male germ cells retain their nuclear integrity even after freezing epididymides or testes in freezers without cryoprotectant. Since this cryopreservation technique is very simple and allows storage at -80�C for at least several months, it may enable transportation of mouse male germ cells internationally on dry ice, even when the senders are not specialized in cryopreservation.