Carbohydrate response element binding protein (ChREBP) is a transcription factor activated by glucose that is highly expressed in liver, pancreatic β-cells, brown and white adipose tissues, and muscle. We reported that hepatic suppression of the Chrebp gene improves hepatic steatosis, glucose intolerance, and obesity in genetically obese mice. Moreover, we have studied the role of ChREBP with special reference to feedforward and feedback looping in liver and pancreatic β-cells. Recently, several groups reported that (1) glucose activates ChREBP-α transactivity and in turn ChREBP-α induces ChREBP-β on both transcriptional and translational levels in adipose tissues, and (2) ChREBP regulates glucose transporter type 4 mRNA levels, which may affect glucose uptake in adipose tissues. Moreover, in adipose tissues of obese patients, Chrebpb mRNA levels were much lower than those in lean subjects, while the levels were much higher in liver of obese patients than those in lean subjects. These findings suggest that Chrebpb mRNA levels are different in various tissues and probably in the stages of diabetes mellitus. Herein, we review recent progress in the study of ChREBP with special references to (1) the mechanisms regulating ChREBP transactivity (posttranslational modifications, intramolecular glucose sensing module, feedforward mechanism, and the feedback loop between ChREBP and its target genes), and (2) the role of ChREBP in liver, pancreatic islets and adipose tissues. Understanding the role of ChREBP in each tissue will provide important insight into the pathogenesis of metabolic syndrome.

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Hypercalcemia with concomitant elevation of serum parathyroid hormone (PTH) and PTH-related protein (PTHrP) levels was found in a patient with advanced gastric carcinoma and multiple liver metastases. The most common features are hypercalcemia associated with hypersecretion of PTHrP and physiological suppression of PTH secretion in the syndrome of humoral hypercalcemia of malignancy (HHM). Although we initially made a diagnosis of primary hyperparathyroidism concomitant with HHM due to gastric cancer, diagnostic imaging studies, such as echography, CT, sestamibi scintigraphy, and autopsy findings, did not reveal evidence of any parathyroid tumors or ectopic parathyroid glands in the mediastinum. Both primary and metastatic tumor cells showed positive staining with PTH-specific antibody as well as PTHrP-specific antibody on immunohistochemical examination. PTH concentration in the cytosolic fraction of the metastatic tumor was elevated compared to that from a control patient with no calcium metabolic disorders in vitro. These findings indicated that PTH secreted ectopically by gastric cancer cells, not by parathyroid glands, caused hypercalcemia in this patient. To our knowledge, this is the first case report of PTH-secreting gastric carcinoma cells. We report the case and a review of the previous reported PTH-secreting non-parathyroid tumors along with the mechanisms of secretion.

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We performed a crossover study in hypertensive patients with type 2 diabetes to compare olmesartan (40 mg/day) with telmisartan (80 mg/day) in terms of their antihypertensive and metabolic effects. The subjects were 36 patients (20 men and 16 women) with type 2 diabetes who did not achieve a blood pressure <130/80 mmHg following treatment with olmesartan at 40 mg/day or telmisartan at 80 mg/day for 8 weeks or more. The primary endpoint was the blood pressure reduction rate, while the secondary endpoints were BMI, parameters of glucose metabolism, HMW-adiponectin, hs-CRP and lipids metabolism. All parameters were measured in Weeks 0, 12, and 24. Treatments were switched in Week 0, and Week 12 and the following results were obtained. There were 1) no significant differences in baseline characteristics; 2) no significant difference of the blood pressure reduction rate; 3) significant reductions of HbA1c (NGSP), FPG and HOMA-IR in olmesartan group; 4) a significant increase of HDL-C in olmesartan group; 5) a decrease of hs-CRP and a increase of HMW-adiponectin in olmesartan group; and 6) a positive correlation between the percent changes of HOMA-IR and hs-CRP in olmesartan group. In conclusion, there was no difference of the blood pressure reduction achieved at the highest dose in olmesartan group and telmisartan group. But improvement of glycemic control and insulin resistance was only observed in olmesartan group. Because there was a correlation between the percent changes of HOMA-IR and hs-CRP, these effects of olmesartan might be mediated by an anti-inflammatory action.

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Ghrelin is the endogenous ligand for the growth hormone-secretagogue receptor expressed in various tissues including the heart, blood vessels and kidney. This study sought to determine the effects of long-term treatment with ghrelin (10 nmol/kg, twice a day, intraperitoneally) on the hypertension induced by high salt (8.0% NaCl) diet in Dahl salt-sensitive hypertensive (DS) rats. Systolic blood pressure (SBP) was measured by a tail cuff method. During the treatment period for 3 weeks, high salt diet increased blood pressure compared to normal salt (0.3% NaCl) diet, and this hypertension was partly but significantly (P<0.01) attenuated by simultaneous treatment with ghrelin. Ghrelin significantly increased urine volume and tended to increase urine Na⁺ excretion. Furthermore, ghrelin increased urine nitric oxide (NO) excretion and tended to increase renal neuronal nitric oxide synthase (nNOS) mRNA expression. Ghrelin did not alter the plasma angiotensin II level and renin activity, nor urine catecholamine levels. Furthermore, ghrelin prevented the high salt-induced increases in heart thickness and plasma ANP mRNA expression. These results demonstrate that long-term ghrelin treatment counteracts salt-induced hypertension in DS rats primarily through diuretic action associated with increased renal NO production, thereby exerting cardio-protective effects.

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Association between autoimmune thyroid diseases (AITD) and hepatitis C is controversial, but may occur or worsen during alpha-interferon treatment. The mechanism responsible for autoimmune diseases in infected patients has not been fully elucidated. This study aims to evaluate the frequency of AITD in chronic hepatitis C and the association of chemokine (CXC motif) ligand 10 (CXCL10) and AITD. One hundred and three patients with chronic hepatitis C and 96 controls were prospectively selected to clinical, hormonal, thyroid autoimmunity and ultrasound exams, besides thyroxine-binding globulin (TBG) and CXCL10 measurements and hepatic biopsies. The frequency of AITD among infected subjects was similar to controls. TT3 and TT4 distributions were right shifted, as was TBG, which correlated to both of them. Thyroid heterogeneity and hypoechogenicity were associated with AITD. Increased vascularization was more prevalent in chronic hepatitis C.CXCL10 was higher in infected patients (p=0.007) but was not related to thyroid dysfunction. Increase in CXCL10 levels were consistent with hepatic necroinflammatory activity (p=0.011). In summary, no association was found between chronic hepatitis C and AITD. Infected subjects had higher TT3 and TT4 which were correlated to TBG. Increased CXCL10 was not associated to thyroid dysfunction in HCV-infected population.

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This study is to explore the role of IL-23/IL-17 axis in subjects with Graves’ disease, while IL-23/IL-17 axis plays an important role in a number of autoimmune diseases, but it’s not clear in Graves’ disease. Thirty-three patients with Graves’ disease as a GD group, 15 patients with euthyroid GD as eGD group and 22 healthy volunteers as a control group whose age- and sex-matched. Peripheral blood was collected and peripheral blood mononuclear cells (PBMCs) were isolated in the both groups, then PBMCs were cultured in the presence or absence of IL-23 in vitro. The expression of retinoid-related orphan receptor gamma t (RORγt) and IL-17 mRNA were examined by Semi-quantitative RT-PCR, and the levels of IL-17 protein were measured by enzyme-linked immunosorbent assay. The expression of RORγt, IL-17 mRNA and IL-17 protein levels were markedly higher in GD and euthyroid GD group as compared with the control group. IL-17 levels were still higher in euthyroid GD patients. When PBMCs derived from the three groups were cultured in vitro with or without IL-23, the expression of RORγt in GD group with IL-23 dramatically increased as compared with that in GD group without IL-23 and in control group with IL-23. RORγt expression of PBMCs from eGD group cultured with IL-23 was increased compared with that cultured without IL-23. The levels of IL-17 mRNA and the protein were also significantly higher than that of GD and eGD cultured without IL-23 and control group. There was no difference of the expression of RORγt mRNA and IL-17 protein levels between GD and eGD group cultured with or without IL-23. Our studies demonstrated that IL-23/IL-17 axis is associated with the pathogenesis of Graves’ disease in it activated term. This effect is not dependent on thyroid function, but may be associated to the immunity.

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In pancreatic β-cells, glucose metabolism leads to closure of ATP sensitive K⁺ channels (K_ATP channel) and Ca²⁺ influx, which is regarded as a required step for triggering of insulin release. Here, we demonstrate that glucose triggers rapid insulin release independent from its action on K_ATP channels given the cellular cAMP is elevated. We measured insulin release from rat pancreatic islets by static and perifusion experiments. Changes in cytosolic free Ca²⁺ concentration ([Ca²⁺]_i) were monitored using fura-2 loaded rat pancreatic β-cells. Glucose-induced insulin release was abolished when Ca²⁺ influx was inhibited by a combination of 250 μM diazoxide, an opener of K_ATP channel, and 10 μM nifedipine, a blocker of L-type voltage-dependent Ca²⁺ channels. However, with both nifedipine and diazoxide, glucose induced a 5-fold increase in insulin release in the presence of 10 μM forskolin, an activator of adenylyl cyclase. In the presence of diazoxide, nifedipine, and forskolin, 22 mM glucose sharply increased the rate of insulin release within 2 min which peaked at 6 min: this was followed by a further gradual increase in insulin release. In contrast, it lowered [Ca²⁺]_i with a nadir at 2-3 min followed by a gradual increase in [Ca²⁺]_i. The glucose effect was mimicked by 20 mM α-ketoisocaproic acid, a mitochondrial fuel, and it was nullified by 2 mM sodium azide, an inhibitor of mitochondrial electron transport. Cerulenin, an inhibitor of protein acylation, decreased the glucose effect. In conclusion, a rise in [Ca²⁺]_i through voltage-dependent Ca²⁺ channels is not mandatory for glucose-induced triggering of insulin release.

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Adipokines are associated with obesity. However, the relationships between adipokines, specifically vaspin, obesity, and obesity-related variables remain controversial, and only a few studies have been conducted which examines them in children. We investigated the relationships between obesity in prepubertal Korean children and three types of adipokines: vaspin, leptin, and visfatin. In this cross-sectional study, 168 nine-year-old boys and 176 nine-year-old girls participated in a school-based health examination program. Children were classified as overweight using the Korean Pediatric Society 2007 guidelines. Overweight boys and girls had higher leptin and vaspin levels than both boys and girls of normal weight, whereas only overweight boys had higher visfatin levels than normal weight boys. Leptin, visfatin and vaspin concentrations were correlated with obesity-related variables. A multiple logistic regression analysis showed that systolic blood pressure (SBP), total cholesterol (TC), alanine aminotransferase (ALT), homeostasis model assessment of insulin resistance (HOMA-IR), leptin, and vaspin were associated with an increased risk of being overweight, whereas high-density lipoprotein (HDL) cholesterol was associated with a decreased risk of being overweight. Elevated vaspin and leptin levels are associated with obesity in prepubertal Korean children.

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In several countries including Japan, people without obesity but with a clustering of metabolic risk factors (MetRFs) were not considered to have the metabolic syndrome (MetS). Here, we examined whether lifestyle characteristics differed between non-obese and obese subjects with or without a clustering of MetRFs. From a population-based cross-sectional study of Japanese subjects aged ≥ 40 years, 1,601 subjects (age: 61.9 ± 10.3 years; 710/891 men/women) were recruited. Physical activity status and daily nutritional intake were estimated using questionnaires. A clustering of MetRFs was defined based on the presence of at least two non-essential risk factors for the diagnosis of the MetS in Japan. Energy intake was not higher in subjects with a clustering of MetRFs compared with those without. Among men, energy expenditure at work was significantly lower in non-obese (9.0 ± 8.2 vs. 11.3 ± 9.3 metabolic equivalents (METs), P = 0.025) and obese (9.0 ± 7.9 vs. 11.6 ± 9.4 METs, P = 0.017) subjects with a clustering of MetRFs than in those without. Multiple logistic regression analysis showed that energy expenditure at work was significantly associated with a clustering of MetRFs after adjusting for possible confounding factors including total energy intake. The ORs (per 1 METs) were 0.970 (95% CI, 0.944–0.997; P = 0.032) in non-obese men and 0.962 (0.926– 0.999; P = 0.043) in obese men. Similar associations were not observed in women. In Japanese males, lower physical activity, but not excessive energy intake, is a risk factor for a clustering of MetRFs independent of their obesity status.

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Children and adolescents represent 1–1.5% of all patients with thyroid cancer (TC). The vast majority of TC in children and adolescents is papillary TC; follicular TC (FTC) is exceedingly rare. In this study, we evaluate the clinical and pathological features of FTC in children and adolescents. We also report the risk factors for post-operative tumor recurrence and the associated outcomes. Twenty children and adolescents (under 21 years old) with FTC have been treated and followed at Noguchi Thyroid Clinic and Hospital Foundation since 1946. All patients underwent surgery (lobectomy, 11; subtotal thyroidectomy, 8; and total thyroidectomy, 1), and 8 patients received postoperative external beam radiation therapy. The incidence of FTC in children and adolescents was 1.9% among all FTC patients treated in our hospital. Histopathology revealed vascular and capsular invasion in 9 and 20 patients, respectively. The tumor recurrence rate in FTC with vascular invasion is significantly higher than in those without it (p = 0.038). No other factors were significant. Patients with recurrences were treated with completion thyroidectomy and ¹³¹I radioactive iodine therapy. There were no significant differences in the rates of disease-free survival or cause-specific survival when pediatric/adolescent FTC patients were compared to adults with FTC. FTC is very rare among children and adolescents, but the outcomes are similar to those observed among adults. Vascular invasion is poor prognostic indicator in pediatric/adolescent FTC patients.

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Follicular thyroid carcinoma (FTC) is divided into two categories: minimally and widely invasive FTC. Generally, the prognosis of minimally invasive FTC is excellent, but patients showing certain characteristics have a dire prognosis. In this study, we investigated the prognostic factors of minimally invasive FTC using a series of 292 patients. On multivariate analysis, extensive (4 or more) vascular invasion, age ≥ 45 years, and tumor size > 4 cm were independent prognostic factors of patient disease-free survival (DFS). Distant metastasis at diagnosis (M1) was the strongest prognostic factor of cause-specific survival (CSS). Extensive vascular invasion and tumor size > 4 cm also independently affected patient carcinoma death. Capsular invasion was not related to patient prognosis. The ten-year DFS rate of patients with extensive vascular invasion was 80%, which was poorer than that of those having tumor size > 4 cm (91%) and aged 45 years or older (90%). These findings suggest that 1) M1 most strongly affects the CSS of patients, and 2) M0 patients with extensive vascular invasion may be candidates for completion total thyroidectomy and radioactive iodine ablation.

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Osteoporosis causes an enormous health and economic impact in Japan. We investigated the relation between lifestyle and bone fracture in middle-aged and elderly women. This was a population-based, multicenter, cross-sectional survey for postmenopausal osteoporosis in Chiba City, Japan (Chiba bone survey). This survey included 64,809 Japanese women aged > 40 years. All participants underwent anthropometric measurements including bone mineral density (BMD) and completed a structured, nurse-assisted, self-administered questionnaire also including patient lifestyle. Bone fracture during the recent 5 years was observed in 5.3%, and the fracture group had significantly higher age, BMI, and prevalence of delivery, family histories of kyphosis and hip fracture, diabetes mellitus (DM), dyslipidemia, kidney disease, exercise, fall, and osteoporosis, and had significantly lower BMD and proportion of menstruating participants. Logistic regression analysis revealed that bone fracture was closely associated with not only low bone mass but also age, fall, family histories of kyphosis and hip fracture, DM, kidney disease, menopause, and lifestyle factors of dieting, exercise, and alcohol. Women’s health care focusing on lifestyle-related fracture risks such as dieting, exercise, and alcohol appears necessary to prevent bone fracture in postmenopausal osteoporosis.

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The somatostatin analog lanreotide Autogel has proven to be efficacious for treating acromegaly in international studies and in clinical practices around the world. However, its efficacy in Japanese patients has not been extensively evaluated. We examined the dose-response relationship and long-term efficacy and safety in Japanese patients with acromegaly or pituitary gigantism. In an open-label, parallel-group, dose-response study, 32 patients (29 with acromegaly, 3 with pituitary gigantism) received 5 injections of 60, 90, or 120 mg of lanreotide Autogel over 24 weeks. Four weeks after the first injection, 41% of patients achieved serum GH level of <2.5 ng/mL and insulin-like growth factor-I (IGF-I) level was normalized in 31%. Values at Week 24 were 53% for GH and 44% for IGF-I. Dose-dependent decreases in serum GH and IGF-I levels were observed with dose-related changes in pharmacokinetic parameters. In an open-label, long-term study, 32 patients (30 with acromegaly, 2 with pituitary gigantism) received lanreotide Autogel once every 4 weeks for a total of 13 injections. Dosing was initiated with 90 mg and adjusted according to clinical responses at Weeks 16 and/or 32. At Week 52, 47% of patients had serum GH levels of <2.5 ng/mL and 53% had normalized IGF-I level. In both studies, acromegaly symptoms improved and treatment was generally well tolerated although gastrointestinal symptoms and injection site induration were reported. In conclusion, lanreotide Autogel provided early and sustained control of elevated GH and IGF-I levels, improved acromegaly symptoms, and was well tolerated in Japanese patients with acromegaly or pituitary gigantism.

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Thyroid cancers arising from a thyroglossal duct cyst (TGDC) are rarely reported. No clear consensus exists regarding optimal management. In this light, TGDC carcinomas recently treated at Asan Medical Center, as well as previously reported cases in the literature, were reviewed. There were ten patients who were diagnosed with TGDC carcinoma at our institution. All patients underwent pre-operative fine-needle aspiration biopsy (FNAB). Nine patients were suspected of having papillary carcinoma following cytology. The Sistrunk operation (SO) was performed in four patients, SO with total thyroidectomy (SO/TT) was performed in three patients, and SO/TT with neck dissection was performed in three patients. Six patients who received total thyroidectomy underwent radioactive iodine (RAI) therapy and T4 suppression. With a median follow-up period of 28.5 months, two patients showed recurrence and one of them died of the disease. We analyzed 163 cases from 1990 to 2012 with three or more cases TGDC carcinoma, including the present study. Among 48 patients who underwent FNAB, 75% had papillary thyroid carcinoma (PTC). SO, SO/TT, or SO/TT with neck dissection was performed in 27%, 41%, and 32% of patients, respectively. Among 119 patients who received total thyroidectomy, 36% had concomitant PTC in the thyroid. Among 52 patients who received neck dissection, 69% had cervical nodal involvement. The results of our review suggest that when TGDC carcinoma is suspected, ultrasonography and, if necessary, FNAB should be performed. If these tests reveal a suspected lesion in the thyroid or lymph node, SO/TT and lymph node dissection should be performed.

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Type 2 11β-hydroxysteroid dehydrogenase encoded by the HSD11B2 gene converts cortisol to inactive cortisone, and alteration in this enzymatic activity might affect glucose homeostasis by affecting circulating levels or tissue availability of glucocorticoids. We investigated the association of HSD11B2 variant with glucose homeostasis. Subjects with normal glucose tolerance (n=585), impaired glucose tolerance (n=202) and type 2 diabetes (n=355) were genotyped for a highly polymorphic CA-repeat polymorphism in the first intron of HSD11B2. Allele and genotype frequencies differed between normal and impaired glucose tolerance (P = 0.0014 and 0.0407, respectively; 4 degree of freedom) or type 2 diabetes (P = 0.0053 and 0.0078), with significant linear trends between the repeat length and the phenotype fraction. In normal subjects, total CA-repeat length was negatively correlated with fasting insulin and HOMA-β. Thus, subjects having more CA repeats are susceptible to developing abnormal glucose tolerance, whereas normal subjects carrying more CA repeats appeared to have frugal characteristics in insulin secretion.

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Recent data suggest that variations in calcium intake may influence body weight and composition; however, the relationship between daily calcium intake and muscle mass has not been well established. The objective of this study was to assess the relationship between daily calcium intake and sarcopenia. We analyzed data for older adults (over 60 years) from the fourth Korea National Health and Nutrition Examination Survey (KNHANES) conducted in 2009. A total of 1339 Non-Obese (BMI between 18.5 and 25 kg/m²), older adults (592 men and 707 women) were enrolled. Dietary variables were assessed using a nutrition survey that used a 24-hour recall method. Daily calcium intake based on the consumption of each food item was calculated. Sarcopenia was defined as an appendicular skeletal muscle mass divided by body weight less than 2 SD below the sex-specific mean for young adults. We found that daily calcium intake was negatively correlated with total body fat percentage and positively correlated with appendicular skeletal mass (p<0.001). Participants with sarcopenia appear to have significantly lower daily calcium intakes than participants without sarcopenia (p<0.001). The unadjusted prevalence of sarcopenia according to daily calcium intake tertiles were 6.3%, 4.3%, and 2.7% in tertiles 1, 2, and 3, respectively. After adjustment for age, sex, BMI, total energy intake, and lifestyle factors, compared with those in the lowest tertile of daily calcium intake, participants in the highest tertile had an odds ratio for sarcopenia of 0.295 (95% confidence interval, 0.087-0.768; p for trend = 0.014). We found that daily calcium intake, corrected for total energy intake and serum 25(OH)D status, was significantly lower in subjects with sarcopenia than in those without. Our results suggest a strong inverse association between daily calcium intake and sarcopenia in non-obese, older Korean adults.

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The mechanism that initiates regeneration of pancreatic β-cells is not clear at present. The vagal nerve is implicated in the regulation of gastrointestinal functions, glucose metabolism and proliferation of pancreatic β-cells under physiological conditions. To elucidate the triggering mechanism of the regeneration of pancreatic β-cells, we examined the involvement of the vagal nerve. To this end, we employed a rat pancreatic duct ligation (DL) model, in which profound β-cell neogenesis and β-cell proliferation were observed within a week. We administered atropine to block the vagal nerve. Administration of atropine inhibited proliferation of β-cells in both islets and islet-like cell clusters (ICC), without affecting ductal cell proliferation in the ligated pancreas. The numbers of PDX-1 and MafB-positive cells in or attaching to the ducts were significantly reduced by atropine. MafB/glucagon and MafB/insulin double-positive cells were also decreased by atropine. Finally, atropine reduced the number of MafA-positive ductal cells, all of which were positive for insulin, by 50% on day 5. These results strongly suggest that the vagal nerve is involved in β-cell proliferation, induction of endocrine progenitors and neogenesis of α- and β-cells.

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