The Japan Endocrine Society (JES) attempted to develop guidelines for the diagnosis and treatment of primary aldosteronism (PA). The Task Force Committee (TFC) was composed of a chair, selected by the JES, and additional experts. Systematic reviews of available evidence for Japanese patients were used to recommend the key treatment and prevention. We have evaluated the methods of screening, confirmatory tests and imaging, plus adrenal vein sampling (AVS). Consensus was guided by systematic review of evidence and discussion during each annual meeting of the JES, plus its related meetings, and by e-mail communication. The drafts prepared by TFC were reviewed successively by the members of Research on Intractable Diseases provided by the Japanese Ministry of Health, Labour and Welfare, and in comments from the JES’s councilors. At each stage of review, TFC received written comments and incorporated suggested changes. In conclusion, all patients with hypertension should be screened for PA, because of the high prevalence of cardiovascular disease and the current low case-detection rate in Japan. Case detection can be performed in hypertensive patients and those with hypokalemia by determining the aldosterone/renin ratio, and the diagnosis of PA can be confirmed by two of three confirmatory tests. The presence of a unilateral aldosterone-producing adenoma should be established/excluded by AVS by an experienced radiologist, optimally followed by laparoscopic adrenalectomy. In contrast, patients with bilateral adrenal hyperplasia, or those unsuitable for surgery, are optimally treated medically with mineralocorticoid receptor antagonists.

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Genome-wide association studies (GWAS) have facilitated a substantial and rapid rise in the number of confirmed genetic susceptibility variants for type 2 diabetes (T2D). Approximately 40 variants have been identified so far, many of which were discovered through GWAS. This success has led to widespread hope that the findings will translate into improved clinical care for the increasing numbers of patients with diabetes. Potential areas or clinical translation include risk prediction and subsequent disease prevention, pharmacogenetics, and the development of novel therapeutics. However, the genetic loci so far identified account for only a small fraction (approximately 10%) of the overall heritable risk for T2D. Uncovering the missing heritability is essential to the progress of T2D genetic studies and to the translation of genetic information into clinical practice.

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We examined children who were diagnosed with asymptomatic type 2 diabetes by school medical examinations to investigate the existence of glucokinase (GCK) gene defects in this group. Among 20 children diagnosed with asymptomatic type 2 diabetes by school medical examinations between 2003 and 2009 at our 2 hospitals, 8 were classified as non-obese type. Among them, we screened 5 children (2 boys and 3 girls; age: 8-13 years) who had mild elevation of fasting plasma glucose (108-134 mg/dL) with slightly high internationally standardized HbA1c levels (6.3-6.9%) at first close examination. Written informed consent was obtained and all families agreed to participate in this study. We found 4 different mutations (G223S, G81C, S336X and T228M) in 4 of the examined children. The blood glucose control levels had not become worse in any children during the 2-6 years follow-up period. The inheritance of diabetes with GCK gene defect was later confirmed in 1 family. These results suggest that GCK gene defects exist in non-obese children who are diagnosed with asymptomatic diabetes by school medical examinations. Cases of diabetes that are caused by GCK mutations may not be as rare in Japanese subjects as previously described and could be found in patients tentatively diagnosed as type 2 diabetes.

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Neurogenesis, which occurs not only in the developing brain but also in restricted regions in the adult brain including the forebrain subventricular zone (SVZ), is regulated by a variety of environmental factors, extracellular signals, and intracellular signal transduction pathways. We investigated whether the transcription factor cAMP response element (CRE)-binding protein (CREB) is involved in the regulation of cell proliferation of neural stem cells (NSCs) isolated from the SVZ of adult mice. Treatment of NSCs with the protein kinase A (PKA) inhibitors H89 and KT5720 inhibited epidermal growth factor (EGF)-stimulated NSC proliferation. Similar inhibition was observed when a dominant-negative mutant of CREB (MCREB) was expressed. EGF treatment increased CRE-mediated transcriptional activity, but this increase was much less than that caused by treatment with the adenylate cyclase activator forskolin, which changed neither basal nor EGF-stimulated proliferation of NSCs. Neither PKA inhibitors nor MCREB expression blocked EGF-induced phosphorylation of extracellular signal-regulated kinase (ERK), a protein kinase mediating EGF’s mitogenic action. However, MCREB suppressed EGF-induced expression of several immediately early genes including c-fos, c-jun, jun-B, and fra-1 and subsequent AP-1 transcriptional activation. MCREB expression also inhibited the ability of EGF to stimulate transcriptional activation mediated by the serum response element (SRE), a promoter sequence regulating c-fos gene expression. These results suggest that basal activity of CREB is required for the mitogenic signaling of EGF in NSCs at a level between ERK activation and SRE-mediated transcriptional activation.

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Recently, it is implicated that the abnormality of Akt signaling pathway is involved in the diabetic pathology. Previous studies have demonstrated that berberine could decrease blood glucose by elevating liver glycogen synthesis. However, the underlying mechanism is still unclear. In the present study, we investigated the effects of berberine on fasting blood glucose, liver glycogen, Akt, Glycogen synthase kinase-3, glucokinase and insulin receptor substrate (IRS) in alloxan-induced diabetic mice, exploring its possible hypoglycemic mechanism. We found that in alloxan-induced diabetic mice, the high blood glucose was significantly lowered by berberine treatment. Liver glycogen content, the expression and activity of glucokinase and the phosphorylated Akt and IRS were all significantly reduced in diabetic mice whereas berberine blocked these changes. Berberine also depressed the increasing of phosphorylated GSK-3β in diabetic mice. Collectively, Berberine upregulates the activity of Akt possibly via insulin signaling pathway, eventually lowering high blood glucose in alloxan-induced diabetic mice.

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This paper reports the case of an infant presenting with sexual ambiguity at birth. The child presented with labia majora synechia, thready genital tubercle and perineal hypospadias. The karyotype was 46,XY. Low testosterone levels with no response to hCG administration, associated with high LH level for her age, high FSH level, high inhibin B levels and normal AMH indicated a lack of LH receptivity and prompted us to screen the LHCGR gene for mutations. A previously described missense mutation (p.Cys131Arg) was identified at homozygous state in the propositus and at heterozygous state in the mother. This variation, however, was not found in the father. Our attention was drawn by the presence of several single nucleotide polymorphisms (SNPs), identified at homozygous state without any paternal contribution from exon 1 to exon 10 of LHCGR, suggesting a paternal deletion. Array DNA analysis was performed revealing a large deletion extending from 61,493 to 135,344 bp and including the LHCGR gene. Adequate genetic counselling was provided. This paper describes the first application of prenatal diagnosis in LHCGR deficiency for 46,XY disorders of sex development with the subsequent delivery of a normal baby.

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In Japan, the growth hormone (GH) assay has been standardized since April 2005 through use of a uniform recombinant human GH (rhGH) standard. Since then, GH values measured using the rhGH standard have been approximately 40% lower than previous values measured using kit standards based on the WHO standards for hGH of pituitary origin. However, the Japanese criteria for evaluating treatment outcomes for acromegaly have remained the same: a nadir GH during a 75 g OGTT <1 μg/L is considered cured, 1≤GH<2.5μg/L is considered inadequately controlled, and ≥2.5 μg/L is considered poorly controlled, instead of these levels were lowered to 60%, i.e. from 1 to 0.6 μg/L for cured and from 2.5 to 1.5μg/L for inadequately controlled (termed as “newly proposed criteria” in this study). We investigated the effects of standardization of the GH assay on the evaluation of post-surgical disease activity in 50 patients with acromegaly (M/F 19/31, 21-72 yr.). Post-surgical nadir GH levels during OGTT were positively correlated with the IGF-I SD score 3 months after TSS. Five of 6 patients whose post-surgical nadir GH levels ranged between 0.6 and 1 μg/L had normal serum IGF-I levels 3 months after TSS. Rates of improvement in glucose metabolism did not differ when patients were classified based on the present criteria vs. the newly proposed criteria. In conclusion, the current Japanese remission criteria for acromegaly still accurately reflect post-surgical disease activity in most patients, though long-term observation is still required.

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Polycystic thyroid disease (PCTD) is characterized by multiple thyroid cysts detected by ultrasonography, the absence of thyroid autoantibodies, and susceptibility to the development of hypothyroidism due to a high iodine intake. It is necessary to obtain histopathological information on PCTD in order to clarify the cause of hypothyroidism. We retrospectively reviewed three patients with PCTD and small papillary thyroid cancer who underwent thyroidectomy. We observed the thyroid tissues pathologically in areas with and without multiple cysts, and compared them with those of multinodular goiter with cysts. In the patients with PCTD, there were multiple enlarged follicles that resembled enlarged normal follicles and differed from those found in multinodular goiter in terms of their shape. Huge follicles corresponded to the cysts that were detected by ultrasonography. Each follicle contained colloid. Follicular cells in enlarged follicles comprised low cuboidal epithelium that appeared normal. These findings were common in the 3 patients with PCTD. In Conclusion the PCTD patients had multiple enlarged follicles that seemed to decrease the total number of follicular cells, and may be a cause of hypothyroidism. We believe that PCTD is a new entity of thyroid disease based on the pathological findings.

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Endogenous Cushing’s syndrome (CS) is associated with a high incidence of cardiovascular morbidity and mortality resulting from the co-existence of multiple cardiovascular risk factors which probably induce a state of endothelial dysfunction. Recently, studies conducted in vitro as well as in normal human subjects suggest a direct role of cortisol in the causation of vascular dysfunction in this disorder. We non-invasively assessed the vascular reactivity and its potential association with elevated cortisol levels in patients of CS. A single time point observational study was conducted in 18 patients of CS and 15 age and gender matched healthy subjects. Vascular reactivity was assessed non-invasively by measuring the peripheral pulse wave form changes during reactive hyperemia (RH) using digital Photoplethysmography (PPG). Parameters measured were pulse wave form amplitude (PWA), slope and pulse transit time (PTT). Maximal percentage changes in PWA during RH with reference to baseline were significantly lower in the patients as compared to controls [23.19% (13.19-53.54) vs 61.71% (38.21-95.36); p=0.0079]. Normalized PTT responses during the 1^st minute of RH were blunted in the patients as compared to controls (1.036 ± 0.026 vs 1.056 ± 0.029; p=0.0425). Percentage changes in PTT during the 2^nd minute of RH were negatively correlated to the morning cortisol levels in patients (r = -0.6328; p=0.0064). The present study showed that endothelium mediated vascular reactivity along with myogenic regulation of vascular tone is impaired in CS. Hypercortisolism possibly plays an important role in the causation of impaired vascular reactivity and endothelial dysfunction in CS.

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Carcinoma metastasis to the thyroid is uncommon, but may be increasing. We describe here a patient with a metastasis of hepatocellular carcinoma (HCC) presenting within a medullary thyroid carcinoma (MTC). The thyroid tumor was detected synchronously with the hepatic lesion by FDG-PET imaging, and HCC metastasis within MTC was confirmed by histological analysis of the thyroid gland.

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Recent studies have reported that leptin and adiponectin are associated with metabolic syndrome. The leptin/adiponectin ratio has been suggested as an atherosclerotic index. The objective of this study was to compare the degree of association of metabolic syndrome with adiponectin levels, leptin levels, leptin/adiponectin ratio, and leptin/high-molecular-weight (HMW) adiponectin ratio. The study population included 3272 Koreans (men: 1915, women: 1357; age, 30-84 years), who had visited the Health Examination Center. Adipokines were divided into quartiles, and metabolic syndrome was defined by the National Cholesterol Education Program Adult Treatment Panel-III (NCEP ATP III). A logistic regression model was fitted to establish the association between adipokines and metabolic syndrome. Adipokines, such as adiponectin, HMW adiponectin, and leptin, were found to be statistically related to metabolic syndrome. Compared to the lowest quartile, the leptin/HMW adiponectin ratio in the highest quartile was associated with a 5-fold increase in the probability of prevalent metabolic syndrome, which was independent of age, smoking status, exercise, low-density lipoprotein (LDL) cholesterol, and body mass index. There was a linear increase in the leptin/HMW adiponectin ratio as the number of metabolic syndrome components increased. The leptin/HMW adiponectin ratio had the highest odds ratio in women. In addition, compared to adiponectin or leptin alone, the AUC of the leptin/adiponectin ratio and leptin/HMW adiponectin ratio was higher for metabolic syndrome. We may suggest that the leptin/HMW adiponectin ratio is not superior to other adipokine markers, but is as effective as the leptin/total adiponectin ratio.

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