Vitamin K2, known as a cofactor for γ-carboxylase, also serves as a ligand of a nuclear receptor, Steroid and Xenobiotic Receptor (SXR). Several clinical trials revealed that vitamin K2 reduced de novo formation and recurrence of hepatocellular carcinoma (HCC). To examine the role of SXR in HCC as a receptor activated by vitamin K2, the cells stably overexpressing SXR were established using a HCC cell line, HuH7. Overexpression of SXR resulted in reduced proliferation and motility of the cells. Further suppression of proliferation and motility was observed when SXR overexpressing clones were treated with vitamin K2. These results suggest that the activation of SXR could contribute to tumor suppressive effects of vitamin K2 on HCC cells.

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In order to study the benefit of adding recombinant human growth hormone (rhGH) to antiresorptive therapy, six patients with idiopathic osteoporosis (IO) receiving alendronate plus calcium and vitamin D were started on daily subcutaneous injections of rhGH 2.0 IU for one year. Fasting morning urine and serum samples were collected for N telopeptide of type-1 collagen (NTX), serum bone-specific alkaline phosphatase (BSAP) and insulin-like growth factor 1 (IGF-1) during the study. Bone mineral density (BMD) was determined by dual-energy x-ray absorptiometry at baseline and 01 year. The effect of rhGH was evaluated comparing the percentage changes in BMD during the last year on ALN with the results obtained with the combined therapy. Serum IGF-1 increased in all patients but variations were not significant (p=0.266). Serum BSAP did not significantly change (p=0.078) but median NTX increased at 45 days from 12.3 to 19.8 nMBCE/mMCr (p=0.012) and tended to return to baseline values at 12 months (15.2 nMBCE/mMCr). Comparing with isolated ALN therapy, a beneficial effect on bone density was observed in 2/3 of the patients at lumbar spine, and percentage change (median and quartiles) varied from -0.65% (-2.33 and 2.23) on ALN to 0.70% (-0.35 and 3.03) on ALN+GH. Although no bone gain occurred at the femoral neck, our data point to a positive effect of rhGH in patients with idiopathic osteoporosis.

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Aims. Dysfunction of the FSH receptor (FSHR) may be involved in some form of male infertility with azoospermia or oligozoospermia. We assessed the discrete codon combination with homo/heterozygous variation of the exon 10 in the FSHR gene. Methods. The genotype of codon 307 and codon 680 were analysed in 352 patients with idiopathic male infertility and 145 men with proven fertility. Results and Conclusion. There was no significant difference in the distributions of each homozygous codon 307 or 680 between these two groups as reported in the literature. However, the population with heterozygous combinations Thr/Ala (codon 307) and Ser/ Asn (codon 680) comprised 26% (38/146) and 44.9% (157/343) in subjects with proven fertility and idiopathic infertile men, respectively. Moreover, the heterozygous genotype Thr/Ala-Ser/Asn was significantly increased in infertile patients compared with the controls. This finding showed that the combination of heterozygous FSHR can be responsible for male infertility.

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Bilateral adrenalectomy is the standard treatment for Cushing’s syndrome (CS) related to ACTH-independent bilateral macronodular hyperplasia (AIMAH), although it imposes life-long adrenal insufficiency. This study reports a clinical case in order to discuss the clinical interest of pharmacological β-blockade of illegitimate membrane receptors and unilateral adrenalectomy as alternatives to bilateral adrenalectomy for treatment of CS due to AIMAH. Evidence for cortisol stimulation by upright posture and insulin-induced hypoglycemia in a patient with CS related to AIMAH led us to try β-blockers as a therapeutic test and then as a first line treatment. Thus, a 3-day β-blocker test (320mg/d propranolol) induced normalization of cortisol secretion, with return of hypercortisolism at the end of the test. A long term treatment with 320mg/d propranolol allowed sustained normalization of cortisol secretion and progressive disappearance of Cushingoid features but after 8 months the patient complained of Raynaud’s syndrome and fatigue. Lowering propranolol dosage or switching to atenolol was less efficient to reduce cortisol levels. Unilateral adrenalectomy was then performed as a second line treatment, leading to normalisation of the 24h urinary cortisol without adrenal insufficiency. Long term control of blood pressure and glycemia were observed during a 7-year follow-up without β-blocker. In conclusion, a 3-day propranolol test may identify patients with AIMAH who can benefit from a long term β-blocker treatment. In case of intolerance to β-blocking agents, unilateral adrenalectomy may allow for long term control of Cushing’s syndrome related to AIMAH without adrenal insufficiency.

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Adiponectin (AdN), an adipokine derived from the adipose tissue, has an insulin-sensitizing effect, and plasma AdN is shown to be decreased in obesity and/or insulin resistant state. To clarify whether changes in AdN are also responsible for the development of glucocorticoid-induced insulin resistance, we examined AdN concentration in plasma and AdN expression in the adipose tissue, using corticotropin-releasing hormone (CRH) transgenic mouse (CRH-Tg), an animal model of Cushing syndrome. We found, unexpectedly, that plasma AdN levels in CRHTg were significantly higher than those in wild-type littermates (wild-type: 19.7±2.5, CRH-Tg: 32.4±3.1μg/mL, p<0.01). On the other hand, AdN mRNA and protein levels were significantly decreased in the adipose tissue of CRH-Tg. Bilateral adrenalectomy in CRH-Tg eliminated both their Cushing’s phenotype and their increase in plasma AdN levels (wild-type/sham: 9.4±0.5, CRH-Tg/sham: 15.7±2.0, CRH-Tg/ADX: 8.5±0.4μg/mL). These results strongly suggest that AdN is not a major factor responsible for the development of insulin resistance in Cushing syndrome. Our data also suggest that glucocorticoid increases plasma AdN levels but decreases AdN expression in adipocytes, the latter being explained possibly by the decrease in AdN metabolism in the Cushing state.

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Neuroendocrine tumors develop in various organs in patients with multiple endocrine neoplasia type 1 (MEN1). Among those, tumors developed in upper gastrointestinal tract, thymus and bronchus have historically been called “carcinoid tumor”. Occurrence of “carcinoid tumor” in other region is very rare and molecular pathogenesis of such tumors is unknown. We have experienced a patient with MEN1 who have developed an “ectopic” retroperitoneal neuroendocrine tumor. Genetic analysis of the MEN1 gene in tumor cells revealed a somatic mutation in exon 9 as well as a germline mutation in exon 10. Allele-specific amplification followed by sequence analysis revealed these two mutations exist on the different allele, indicating both alleles are functionally inactivated. Immunohistochemical staining with an anti-menin antibody revealed that wild-type menin is not expressed in tumor cells. Expression of p27^Kip1 protein is not observed in tumor cells, either. These results confirmed the inactivation of the MEN1 gene as a genetic cause of an ectopically developed neuroendocrine tumor in a patient with MEN1.

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For the diagnosis of Cushing’ s syndrome (CS), the overnight 1 mg dexamethasone suppression test (DST) has been widely used as a standard low-dose DST. However, it is evident that 1 mg DST may not be sensitive enough to detect CS when the cortisol cut-off concentration is 5 μg/dL. Therefore, we developed and validated 0.5 mg DST as a new screening method for diagnosis of ACTH-dependent CS. To compare 0.5 mg DST with 1 mg DST, 110 patients with ACTHdependent CS were enrolled, including 88 with Cushing’ s disease (CD), 8 with subclinical CD and 14 with ectopic ACTH syndrome, as well as 134 control subjects. Subjects were given either 0.5 mg or 1 mg dexamethasone orally at 23:00 on different days, with blood samples collected the following morning between 8:00 and 9:00 to determine plasma cortisol concentration. The area under the receiver operator characteristics curve observing the 0.5 mg DST was higher than that of the 1 mg DST. The most sensitive and specific cut-off value of plasma cortisol concentration using 0.5 mg DST was found to be 3.05 μg/dL with 99.1% sensitivity and 98.4% specificity, identical to the 3 μg/dL cut-off currently used in the Japanese guideline for diagnosis of subclinical CD. In conclusion, 0.5 mg DST is a sensitive and specific screening test for diagnosis of ACTH-dependent CS. We recommend 0.5 mg DST with a cortisol cut-off concentration of 3 μg/dL to be used as the initial step in diagnosing ACTH-dependent CS.

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Congenital nephrogenic diabetes insipidus (CNDI) is a rare inherited disease, characterized by an inability of the kidney to concentrate urine in response to vasopressin. Three different inheritance patterns have been described, i.e., the X-linked recessive form associated with arginine vasopressin V2 receptor (AVPR2) gene mutations, the autosomal recessive and dominant forms of CNDI associated with mutations in the aquaporin-2 (AQP2) gene encoding the vasopressinregulated water channel of the renal collecting duct. Our case is an 18-year-old male patient who complained of severe polyuria since his infancy. But his developmental and growth status were normal. He was diagnosed as CNDI by water deprivation test and genomic DNA sequencing, which revealed high plasma AVP levels but persistently low urine osmolalities to 6 h-water deprivation and the novel missense mutation S216F in exon4 of the AQP2 gene. Immunohistochemistry of renal biopsied tissue revealed that most of the AQP2 labeling was seen intracellularly in a dotted pattern in the collecting duct principal cells. Immunoblotting of urine samples revealed significantly decreased urinary excretion of AQP2 (~7% of normal control). Here, we report a new case of CNDI associated with the novel missense mutation of the AQP2 gene.

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Insulin resistance is mainly present in skeletal muscle in non-obese patients with myotonic dystrophy. Thiazolidinediones are reported to reduce insulin resistance in these patients. However, the effects of pioglitazone in overweight patients with myotonic dystrophy and type 2 diabetes mellitus have not been established. Here, we evaluated the effect of pioglitazone in two poorly-controlled over-weight diabetic patients with myotonic dystrophy. Case 1 was a 41- year-old women (BMI 27.8 kg/m²) with myotonic dystrophy and type 2 diabetes had been treated with 3 mg/day glimepiride and 500 mg/day metformin, but the treatment failed to achieve good glycemic control (HbA_1C 11.8 %). Following admission to the hospital, she was treated with low-dose insulin and 30 mg/day pioglitazone. At 10 days after initiation of therapy, glycemic control was improved, serum IL-6 and hs-CRP decreased, and adiponectin level increased rapidly. Case 2 was a 47-year-old women (BMI 29.2kg/m²) with myotonic dystrophy and type2 diabetes mellitus had been treated with insulin without successful glycemic control (HbA_1C 10.3 %). After admission, she was treated with 15 mg/day pioglitazone. This improved glycemic control, reduced daily insulin requirement, decreased IL-6 and hs-CRP levels rapidly and increased adiponectin level at 10 days after initiation of therapy. In both cases, pioglitazone rapidly improved glycemic control, enhanced adiponectin production, and reduced inflammatory cytokines. These results suggest that pioglitazone may be suitable for these patients.

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Little information on the relationship between blood rheology and atherosclerosis indicators in obese patients is available. We examined blood rheology as assessed by the blood passage time (BPT) with the microchannel method in 109 obese patients. BPT was correlated well with the extent of each metabolic syndrome component. A multivariate regression analysis revealed that the independent contributors to BPT were pulse-wave velocity, an index of arterial stiffness, body mass index and red blood cell. Furthermore, weight reduction intervention significantly decreased BPT. Assessment of rheology may be associated with pulse-wave velocity, and useful to manage obese patients.

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