Continuity of diabetes care among elderly Japanese patients: a medical record review study in a specialized diabetes clinic.

Aims: Continuity of diabetes care is relevant among elderly patients. The aim of this study is to investigate the impact of clinical characteristics on continuing outpatient visits to a specialized diabetes clinic in elderly Japanese patients with diabetes.

Methods: We included outpatients with type 2 diabetes aged ≥ 65 years who first visited our clinic from 2006 to 2009.

Skeletal muscle-specific HMG-CoA reductase knockout mice exhibit rhabdomyolysis: A model for statin-induced myopathy.

HMG-CoA reductase (HMGCR) catalyzes the conversion of HMG-CoA to mevalonic acid (MVA); this is the rate-limiting enzyme of the mevalonate pathway that synthesizes cholesterol. Statins, HMGCR inhibitors, are widely used as cholesterol-reducing drugs. However, statin-induced myopathy is the most adverse side effect of statins.

Circulating malondialdehyde-modified LDL-related variables and coronary artery stenosis in asymptomatic patients with type 2 diabetes.

Aims: To elucidate the levels of malondialdehyde-modified LDL (MDA-LDL)-related variables for predicting coronary artery stenosis (CAS) by coronary CT angiography (CCTA) in asymptomatic patients with type 2 diabetes (T2DM).

Methods: Enrolled were 36 Japanese patients with T2DM who underwent CCTA and in whom MDA-LDL levels were measured. Definition of CAS was luminal narrowing of ≥50%.

Hepatic CREB3L3 controls whole-body energy homeostasis and improves obesity and diabetes.

Transcriptional regulation of metabolic genes in the liver is the key to maintaining systemic energy homeostasis during starvation. The membrane-bound transcription factor cAMP-responsive element-binding protein 3-like 3 (CREB3L3) has been reported to be activated during fasting and to regulate triglyceride metabolism. Here, we show that CREB3L3 confers a wide spectrum of metabolic responses to starvation in vivo.

Ablation of Elovl6 protects pancreatic islets from high-fat diet-induced impairment of insulin secretion.

ELOVL family member 6, elongation of very long-chain fatty acids (Elovl6) is a microsomal enzyme that regulates the elongation of C12-16 saturated and monounsaturated fatty acids and is related to the development of obesity-induced insulin resistance via the modification of the fatty acid composition. In this study, we investigated the role of systemic Elovl6 in the pancreatic islet and β-cell function. Elovl6 is expressed in both islets and β-cell lines.

Comparison of the Framingham risk score, UK Prospective Diabetes Study (UKPDS) Risk Engine, Japanese Atherosclerosis Longitudinal Study-Existing Cohorts Combine (JALS-ECC) and maximum carotid intima-media thickness for predicting coronary artery stenosis in patients with asymptomatic type 2 diabetes.

Aims: To compare the efficacy of Framingham Risk Score (FRS), UK Prospective Diabetes Study (UKPDS) risk engine, a risk score based on the Japanese Atherosclerosis Longitudinal Study-Existing Cohorts Combine (JALS-ECC), the maximum intima-media thickness (max-IMT) determined on coronary computed tomography angiography (CCTA) and their combination in asymptomatic patients with type 2 diabetes.

Methods: A total of 116 Japanese patients with type 2 diabetes underwent CCTA. The risk of coronary heart disease was calculated according to the FRS, UKPDS and JALS-ECC.

Carotid artery plaque and LDL-to-HDL cholesterol ratio predict atherosclerotic status in coronary arteries in asymptomatic patients with type 2 diabetes mellitus.

Aims: To investigate the clinical predictors of coronary atherosclerosis and to assess the utility of maximum-IMT for predicting coronary atherosclerosis in asymptomatic type 2 diabetic patients.

Methods: One hundred one Japanese patients with type 2 diabetes underwent computed tomography coronary angiography. Definitions of coronary artery stenosis and vulnerable coronary plaque were luminal narrowing of ≥50% and any coronary plaque with positive vessel remodeling and low attenuation, respectively.

[Granular cell tumor of the neurohypophysis observed with hypoglycemic attack].

Granular cell tumor of the neurohypophysis (GCT) occurs as a solitary, small, nodular tumor and rarely grows to a sufficient size to present symptoms. The authors report a case of a 30-year-old man with GCT presenting with hypoglycemic attack. Hypoglycemic attack could be due to dysfunction of the hypothalamus and one of the important symptoms of GCT.

TFE3 regulates muscle metabolic gene expression, increases glycogen stores, and enhances insulin sensitivity in mice.

The role of transcription factor E3 (TFE3), a bHLH transcription factor, in immunology and cancer has been well characterized. Recently, we reported that TFE3 activates hepatic IRS-2 and hexokinase, participates in insulin signaling, and ameliorates diabetes. However, the effects of TFE3 in other organs are poorly understood.

Inhibition of ubiquitin ligase F-box and WD repeat domain-containing 7α (Fbw7α) causes hepatosteatosis through Krüppel-like factor 5 (KLF5)/peroxisome proliferator-activated receptor γ2 (PPARγ2) pathway but not SREBP-1c protein in mice.

F-box and WD repeat domain-containing 7α (Fbw7α) is the substrate recognition component of a ubiquitin ligase that controls the degradation of factors involved in cellular growth, including c-Myc, cyclin E, and c-Jun. In addition, Fbw7α degrades the nuclear form of sterol regulatory element-binding protein (SREBP)-1a, a global regulator of lipid synthesis, particularly during mitosis in cultured cells. This study investigated the in vivo role of Fbw7α in hepatic lipid metabolism.

Macrophage Elovl6 deficiency ameliorates foam cell formation and reduces atherosclerosis in low-density lipoprotein receptor-deficient mice.

Objective: Elovl6, a long-chain fatty acid elongase, is a rate-limiting enzyme that elongates saturated and monounsaturated fatty acids and has been shown to be related to obesity-induced insulin resistance via modification of fatty acid composition. In this study, we investigated the roles of Elovl6 in foam cell formation in macrophages and atherosclerosis in mice.

Methods And Results: To investigate the roles of Elovl6 in macrophages in the progression of atherosclerosis, we transplanted bone marrow cells of wild-type or Elovl6(-/-) mice into irradiated LDL-R(-/-) mice that were fed a western diet.

Sterol regulatory element-binding protein-1 determines plasma remnant lipoproteins and accelerates atherosclerosis in low-density lipoprotein receptor-deficient mice.

Objective: Sterol regulatory element-binding protein-1 (SREBP-1) is nutritionally regulated and is known to be a key transcription factor regulating lipogenic enzymes. The goal of this study was to evaluate the roles of SREBP-1 in dyslipidemia and atherosclerosis.

Methods And Results: Transgenic mice that overexpress SREBP-1c in the liver and SREBP-1-deficient mice were crossed with low-density lipoprotein receptor (LDLR)-deficient mice, and the plasma lipids and atherosclerosis were analyzed.

Thunderclap headache without hypertension in a patient with pheochromocytoma.

Pheochromocytoma is a well known, catecholamine-producing tumor characterized by hypertension, headache, hyperglycemia, hypermetabolism, and hyperhydrosis. Approximately 65% of cases of pheochromocytoma were shown to be associated with hypertension. A case of pheochromocytoma that presented with thunderclap headache (TCH) and palpitations is reported.

Protein kinase Cbeta mediates hepatic induction of sterol-regulatory element binding protein-1c by insulin.

Sterol-regulatory element binding protein-1c (SREBP-1c) is a transcription factor that controls lipogenesis in the liver. Hepatic SREBP-1c is nutritionally regulated, and its sustained activation causes hepatic steatosis and insulin resistance. Although regulation of SREBP-1c is known to occur at the transcriptional level, the precise mechanism by which insulin signaling activates SREBP-1c promoter remains to be elucidated.

The liver-enriched transcription factor CREBH is nutritionally regulated and activated by fatty acids and PPARalpha.

To elucidate the physiological role of CREBH, the hepatic mRNA and protein levels of CREBH were estimated in various feeding states of wild and obesity mice. In the fast state, the expression of CREBH mRNA and nuclear protein were high and profoundly suppressed by refeeding in the wild-type mice. In ob/ob mice, the refeeding suppression was impaired.

The up-regulation of microRNA-335 is associated with lipid metabolism in liver and white adipose tissue of genetically obese mice.

MicroRNAs (miRNAs) are short non-coding RNA that post-transcriptionally regulates gene expression. Some miRNAs have been proposed to be associated with obesity. However, miRNAs, which are related to the development of obesity in vivo remains unknown.

Nuclear SREBP-1a causes loss of pancreatic beta-cells and impaired insulin secretion.

Transgenic mice expressing nuclear sterol regulatory element-binding protein-1a under the control of the insulin promoter were generated to determine the role of SREBP-1a in pancreatic beta-cells. Only low expressors could be established, which exhibited mild hyperglycemia, impaired glucose tolerance, and reduced plasma insulin levels compared to C57BL/6 controls. The islets isolated from the transgenic mice were fewer and smaller, and had decreased insulin content and unaltered glucagon staining.

Cholesterol accumulation and diabetes in pancreatic beta-cell-specific SREBP-2 transgenic mice: a new model for lipotoxicity.

To determine the role of cholesterol synthesis in pancreatic beta-cells, a transgenic model of in vivo activation of sterol-regulatory element binding protein 2 (SREBP-2) specifically in beta-cells (TgRIP-SREBP-2) was developed and analyzed. Expression of nuclear human SREBP-2 in beta-cells resulted in severe diabetes as evidenced by greater than 5-fold elevations in glycohemoglobin compared with C57BL/6 controls. Diabetes in TgRIP-SREBP-2 mice was primarily due to defects in glucose- and potassium-stimulated insulin secretion as determined by glucose tolerance test.

Palmitate impairs and eicosapentaenoate restores insulin secretion through regulation of SREBP-1c in pancreatic islets.

Objective: Chronic exposure to fatty acids causes beta-cell failure, often referred to as lipotoxicity. We investigated its mechanisms, focusing on contribution of SREBP-1c, a key transcription factor for lipogenesis.

Research Design And Methods: We studied in vitro and in vivo effects of saturated and polyunsaturated acids on insulin secretion, insulin signaling, and expression of genes involved in beta-cell functions.

Cyclin-dependent kinase inhibitor, p21WAF1/CIP1, is involved in adipocyte differentiation and hypertrophy, linking to obesity, and insulin resistance.

Both adipocyte hyperplasia and hypertrophy are determinant factors for adipocyte differentiation during the development of obesity. p21(WAF1/CIP1), a cyclin-dependent kinase inhibitor, is induced during adipocyte differentiation; however, its precise contribution to this process is unknown. Using both in vitro and in vivo systems, we show that p21 is crucial for maintaining adipocyte hypertrophy and obesity-induced insulin resistance.

Mouse Elovl-6 promoter is an SREBP target.

Elovl-6, a long fatty acid elongase, contributes to de novo synthesis of fatty acids and regulates hepatic insulin sensitivity. Hepatic regulation of Elovl-6 gene expression in various nutritional conditions suggested that, like other lipogenic enzyme genes, Elovl-6 is a target of SREBP-1, a transcription factor governing fatty acid synthesis. Supportively, adenoviral RNAi knockdown of SREBP-1 in mouse liver suppressed Elovl-6 mRNA and fatty acid synthase levels.

Involvement of glomerular SREBP-1c in diabetic nephropathy.

The role of glomerular SREBP-1c in diabetic nephropathy was investigated. PEPCK-promoter transgenic mice overexpressing nuclear SREBP-1c exhibited enhancement of proteinuria with mesangial proliferation and matrix accumulation, mimicking diabetic nephropathy, despite the absence of hyperglycemia or hyperlipidemia. Isolated transgenic glomeruli had higher expression of TGFbeta-1, fibronectin, and SPARC in the absence of marked lipid accumulation.

Crucial role of a long-chain fatty acid elongase, Elovl6, in obesity-induced insulin resistance.

Insulin resistance is often associated with obesity and can precipitate type 2 diabetes. To date, most known approaches that improve insulin resistance must be preceded by the amelioration of obesity and hepatosteatosis. Here, we show that this provision is not mandatory; insulin resistance and hyperglycemia are improved by the modification of hepatic fatty acid composition, even in the presence of persistent obesity and hepatosteatosis.

Even low-intensity and low-volume exercise training may improve insulin resistance in the elderly.

Objective: Moderate to high intensity exercise training is known to ameliorate the coronary risk factors in relation to an improvement in body composition. However, the benefit of low-intensity and low-volume training for these risk factors remains unclear in elderly people. Therefore, we investigated the effects of low-intensity and low-volume exercise training on blood lipid values and insulin resistance in the elderly.