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Objective In addition to excess visceral fat, lipid deposition in the liver and skeletal muscle has been implicated in the pathophysiology of type 2 diabetes and metabolic syndrome. This study was designed to explore the relationship between hepatic and muscular lipid deposition and visceral fat accumulation in 105 middle-aged men with metabolic syndrome. Methods Abdominal computed tomography (CT) was used to simultaneously evaluate the visceral fat area (VFA) and CT Hounsfield unit (HU) values of three different portions of skeletal muscle and the liver. Results A significant inverse correlation was observed between the VFA and the CT HU values of the iliopsoas muscle, back muscle, rectus abdominis muscle and liver. Three types of interventions, i.e., lifestyle modification and treatment with antidiabetic drugs, such as Pioglitazone or Miglitol, caused significant decreases in visceral fat accumulation. The extent of lipid deposition in the liver was strongly correlated with the levels of glucose-lipid metabolic markers, which decreased significantly following Pioglitazone treatment. On the other hand, the amount of lipid deposition in the three skeletal muscles and the liver did not decrease after Miglitol treatment. Conclusion Visceral fat accumulation is accompanied by excess lipid deposition in skeletal muscle and the liver in patients with metabolic syndrome. The CT-based simultaneous, concise evaluations of ectopic lipid deposition and visceral fat mass used in the present study may provide unique information for assessing cardiometabolic risks and the therapeutic impact in patients with diabetes-obesity syndrome.

Brown rice is known to improve glucose intolerance and prevent the onset of diabetes. However, the underlying mechanisms remain obscure. In the current study, we investigated the effect of brown rice and its major component, γ-oryzanol (Orz), on feeding behavior and fuel homeostasis in mice. When mice were allowed free access to a brown rice–containing chow diet (CD) and a high-fat diet (HFD), they significantly preferred CD to HFD. To reduce hypothalamic endoplasmic reticulum (ER) stress on an HFD, mice were administered with 4-phenylbutyric acid, a chemical chaperone, which caused them to prefer the CD. Notably, oral administration of Orz, a mixture of major bioactive components in brown rice, also improved glucose intolerance and attenuated hypothalamic ER stress in mice fed the HFD. In murine primary neuronal cells, Orz attenuated the tunicamycin-induced ER stress. In luciferase reporter assays in human embryonic kidney 293 cells, Orz suppressed the activation of ER stress–responsive cis-acting elements and unfolded protein response element, suggesting that Orz acts as a chemical chaperone in viable cells. Collectively, the current study is the first demonstration that brown rice and Orz improve glucose metabolism, reduce hypothalamic ER stress, and, consequently, attenuate the preference for dietary fat in mice fed an HFD.

Cytotoxic T-lymphocyte antigen-4 (CTLA-4) decreases the immune response of T cells by inactivating the signal that occurs with interaction between CD28 on T cells and B7 on antigen-presenting cells. Gene polymorphisms involving CTLA-4 promoter (-318 C/T), exon 1 (49 A/G), and exon 4 (microsatellite (AT)n) have been linked to Hashimoto's thyroiditis (HT) and other autoimmune diseases. HT also has a reported association with human T-cell lymphotrophic virus-1 (HTLV-1) infection. We investigated the occurrence of CTLA-4 polymorphisms in Japanese patients with HT with and without anti-HTLV-1 antibodies (HTLV-1 Ab). DNA samples from 143 patients with HT and 199 controls were subjected to polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis using the restriction enzymes, Bbv 1, Tse 1, and Mse 1. In the HTLV-1 Ab-positive group the exon 1 G allele was more frequent in patients with HT than in controls (67% vs. 53%, p = 0.0377), and in HTLV-1 Ab-negative group it was also frequent in patients with HT than in controls (68% vs. 53%, p = 0.0041). Frequency of the G allele in HT with HTLV-1 Ab was comparable to those without HTLV-1 Ab. Frequency of polymorphism in the promoter did not differ between patients with HT and controls, nor between controls with and without HTLV-1 Ab. HTLV-1 infection is not associated with CTLA-4 polymorphisms in either HT or controls. HTLV-1 infection is not regulated by genetic factor such as CTLA-4, and may affect occurrence of HT as an independent purely environmental factor.

Brown rice (BR) and white rice (WR) produce different glycaemic responses and their consumption may affect the dietary management of obesity. In the present study, the effects of BR and WR on abdominal fat distribution, metabolic parameters and endothelial function were evaluated in subjects with the metabolic syndrome in a randomised cross-over fashion. In study 1, acute postprandial metabolic parameters and flow- and nitroglycerine-mediated dilation (FMD and NMD) of the brachial artery were determined in male volunteers with or without the metabolic syndrome after ingestion of either BR or WR. The increases in glucose and insulin AUC were lower after ingestion of BR than after ingestion of WR (P= 0·041 andP= 0·045, respectively). FMD values were decreased 60 min after ingestion of WR (P= 0·037v. baseline), but the decrease was protected after ingestion of BR. In study 2, a separate cohort of male volunteers (n27) with the metabolic syndrome was randomised into two groups with different BR and WR consumption patterns. The values of weight-based parameters were decreased after consumption of BR for 8 weeks, but returned to baseline values after a WR consumption period. Insulin resistance and total cholesterol and LDL-cholesterol levels were reduced after consumption of BR. In conclusion, consumption of BR may be beneficial, partly owing to the lowering of glycaemic response, and may protect postprandial endothelial function in subjects with the metabolic syndrome. Long-term beneficial effects of BR on metabolic parameters and endothelial function were also observed.

Summary Activated interleukin (IL)-4Rα stimulates production of IgE through signal transducer and activator of transcription-6 (Stat6) activation in lymphocytes. Genetic studies have shown an association between polymorphisms in the genes encoding IL-4Rα and Stat6 and elevated serum IgE in patients with atopic disease. Some authors, including us, have reported an association of Graves' disease and elevated serum IgE. To analyse the relationship between IL-4Rα and Stat6 polymorphisms and elevated serum IgE in patients with Graves' disease, 169 patients with Graves' disease were studied. We investigated whether these polymorphisms affect IL-4Rα–Stat6 signalling in cultured human lymphocytes. A high frequency of both the Ile50 polymorphism in IL-4Rα and 13GT repeat variants of the Stat6 gene was observed in patients with Graves' disease and elevated serum IgE (Ile50 allele; P

We studied whether a patient with Graves' disease will go into remission during antithyroid drug (ATD) treatment. Remission of Graves' hyperthyroidism is predicted by a smooth decrease in TSH receptor antibody (TRAb) during ATD treatment. Cytotoxic T cell lymphocyte-associated molecule-4 (CTLA-4) may play an important role in the development of Graves' hyperthyroidism and in its remission. We studied A/G polymorphism at position 49 in exon 1 of the CTLA-4 gene in 144 Japanese Graves' patients. We intended to reveal the possible association of CTLA-4 gene polymorphism with the remission of Graves' hyperthyroidism. All patients with Graves' disease were treated with ATD. Thyroid-stimulating antibody and TSH binding inhibitory Ig were measured as TRAb. We analyzed CTLA-4 genotypes and alleles with PCR. We calculated the frequencies of CTLA-4 genotypes and alleles. A significant increase in the frequency of the G allele was seen in Graves' patients compared with controls (P = 0.0095). Graves' patients were divided into three groups (A, B, and C) according to time of TRAb disappearance after the start of ATD treatment. In group A patients TRAb had disappeared within 1 yr after the start of ATD treatment, in group B TRAb had disappeared between the beginning of the second year and the end of the fifth year of treatment, and in group C TRAb continued to be positive after 5 yr of ATD treatment. The frequencies of the GG genotype and the G allele were significantly higher in group C patients with persistently positive TRAb over 5 yr of ATD treatment than in the other groups (P < 0.0001). Group C patients did not have the AA genotype. The periods of time until remission were significantly shorter in the AA genotype. Graves' patients with the G allele need to continue ATD treatment for longer periods.