Interest in the physiologic and pharmacologic role of bioactive compounds present in plants has increased dramatically over the last decade. Of particular interest in relation to human health are the classes of compounds known as the phytoestrogens, which embody several groups of non-steroidal estrogens, including isoflavones and lignans that are widely distributed within nature. The impact of dietary phytoestrogens on normal biologic processes was first recognized in sheep. Observations of sheep grazing on fields rich in clover and cheetahs fed high soy diets in zoos suggested that flavonoids and related phytochemicals can affect mammalian health. Endogenous estrogens have an important role not only in the hypothalamic-pituitary-gonadal axis, but also in various non-gonadal systems, such as cardiovascular systems, bone, and central nervous systems, and lipid metabolism. There have been several clinical studies of hormone replacement therapy (HRT) in post-menopausal women to examine whether HRT has beneficial effects on the cardiovascular system, bone fractures, lipid metabolism, and Alzheimer's disease. In addition, estrogen contributes to the development of some estrogen-dependent cancers, such as breast cancer and prostate cancer and the number of patients with these cancers is increasing in developed countries. Although recent mega-studies showed negative results for classical HRT in the prevention of some of these diseases, the molecules that interact with estrogen receptors are candidate drugs for various diseases, including hormone-dependent cancers. This review focuses on the molecular properties and pharmaceutical potential of phytoestrogens.

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Phenylarsine oxide (PAO) which complexes vicinal thiol groups is a valuable pharmacological tool to investigate the interaction of peptides such as insulin with their receptors and the signal transduction from the receptor to the cell interior. This tool was now used to elucidate the inhibitory effects of insulin and IGF-1 on insulin secretion via their receptors. Insulin and IGF-1 inhibited insulin release from INS-1 cells, an insulin secreting cell line. PAO was able to reverse this inhibitory effect of both hormones. Dimercaptopropanol (DMP), which is well known to antagonize PAO effects, inhibited the abolishment of PAO effect on the inhibitory effect of insulin and IGF-1 regarding insulin release. Membrane bound GLUT2 in INS-1 cells was increased by either insulin and IGF-1 which is counteracted by PAO. Thus the inhibitory effect of insulin and IGF-1 on insulin release is operative and can be disturbed by a thiol interacting compound such as PAO. This may happen at the receptor level or at the sub-receptor level.

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Glucocorticoid (GC)-induced osteoporosis (GIO) is a serious problem for patients taking GC therapy. GC increases risk for fracture. However, there are controversies regarding the threshold of bone mineral density (BMD) in patients with GIO. The present study aimed to examine the relationship between the presence or absence of vertebral fracture and various indices including BMD in 136 female Japanese patients treated with oral GC (102 patients with autoimmune diseases). Moreover, we analyzed the cut-off values of BMD for incidence of vertebral fracture in patients with oral GC use and compared these values with those in control subjects. BMD was measured by dual-energy X-ray absorptiometry of the lumbar spine, femoral neck, and distal one third of radius. We compared various indices between patients taking oral GC with and without vertebral fracture. Age, body height, and body weight were significantly greater, shorter, and lower in the group with vertebral fracture, respectively. As for BMD, age-matched BMD seemed lower in the fracture group, although the differences were significant between both groups only at the femoral neck. Duration of GC treatment was longer in the fracture group. Cut-off values of BMD at lumbar spine, femoral neck, and distal radius were higher in patients with GC treatment compared with those of control group [GC vs control (g/cm²): 0.807 vs 0.716 at lumbar spine; 0.611 vs 0.581 at femoral; 0.592 vs 0.477 at radius]. The sensitivity and specificity were lower in patients with GC treatment compared with those of control group. The present study demonstrated that the thresholds of BMD for vertebral fracture were higher in Japanese female patients with oral GC treatment at any site compared with postmenopausal subjects. The factors other than BMD were considered to affect bone strength and vertebral fracture risk.

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The syndrome of McCune-Albright syndrome (MAS) is clasically defined as a triad presentation with the findings of polyostotic fibrous dysplasia, café-au-lait spots, and sexual precocity. However, not all patients present with complete symptoms. A 52-year-old man was diagnosed as having a variant of McCune-Albright syndrome with the following findings: polyostotic fibrous dysplasia, acromegaly due to pituitary tumor and subclinical hyperthyroidism due to toxic multinodular goiter. Sexual precocity and café-au-lait spots were not noted. Acromegaly was confirmed by laboratory examination (IGF-1, glucose suppression test and TRH stimulation test). Long acting somatostatin analogue was used as treatment. Although the pituitary tumor could not be removed due to technical problems, mass lesions on the cranium were removed subtotally. Histopathological evaluation demonstrated that the lesion complied with fibrous dysplasia. Genomic DNAs were isolated from the craniofacial bones and peripheral leucocytes of the patient. After amplifying the related regions, Gs alpha (Gsα) gene was analysed by automatic DNA sequence analysis. An activating mutation of the Gsα gene (Arg 201 Cys) was found in the genomic DNA isolated from the bone tissue of the patient, but not in the genomic DNA isolated from the blood. We described a case of MAS associated with Gsα mutation in the bone tissue, presenting with polyostotic fibrous dysplasia, subclinical hyperthyroidism and acromegaly.

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The aim of this study was to investigate the effect of strict glycemic control on the carotid artery intima-media thickness (IMT) in type 2 diabetic patients who initially had good glycemic control (HbA1c between 5.8 and 6.4 %). The subjects were 67 patients showing deterioration of the mean HbA1c over 3 years by more than 0.2% from baseline (D group) and 33 subjects showing improvement of the mean HbA1c by more than 0.2% from baseline (A group). The clinical characteristics and annual change of IMT during the observation period were compared between the two groups in a 3-year retrospective longitudinal study. The baseline characteristics and the mean values of BMI, blood pressure, and serum lipids during the study period did not differ significantly between the two groups. However, the mean HbA1c of A group was significantly lower than that of D group (5.67 ± 0.10 vs. 6.28 ± 0.08, mean ± SE, p<0.001). The adjusted annual increase rate of IMT was significantly less in A group than in D group (-0.035 ± 0.019 vs. 0.036 ± 0.015 mm, M ± SEM, p<0.001). These results indicate that further improvement of glycemic control from a good HbA1c value can prevent an increase of IMT in type 2 diabetic patients.

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The three dimensional structures of the C₁X₂G ₃(X₃)X₄C₅ motif of hCG, which is considered to be important for noncovalent assembly of the α- and β-subunits of glycoprotein hormones were analyzed to assess the importance of glycine (Gly) (G) at site X₃ in the motif by the conformational energy calculation using computational procedures. In the C₁M₂G ₃(X₃)C₄C₅ motif of the α-subunit, Ramachandran plot analysis showing the allowed area of the dihedral angles demonstrated that only a Gly residue was allowed at site X₃. In calculating collision with surrounding atoms as a monomer the possible main chain models of the C₁A₂G₃(X₃)Y₄C ₅ motif in the β-subunit showed that only alanine (Ala) (A) or Gly at site X₃ is allowed to alleviate the collision with the cysteine (Cys) (C) residues which form a disulfide bridge. A mutant of the β-subunit with the C₁A₂A₃(X₃)Y₄C ₅ motif (Ala at site X₃) may not compose a heterodimer with the α-subunit because of interference of intermolecular hydrogen bond formation. These findings indicate that the Gly residue at site X₃ (G₃) in the motif is essential for heterodimer formation of glycoprotein hormones. The significance of similar motifs found in various human proteins other than glycoprotein hormones was suggested.

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A 63-year-old male patient was admitted for the treatment of malignant pheochromocytoma with multiple liver metastases. Plasma and urinary levels of catecholamines were elevated. Transcatheter arterial embolization (TAE) with concomitant administration of mitomycin C and gelatin sponge was performed for the treatment of liver metastases. Dose of alpha-1 blocker before TAE was increased to prevent hypertensive crisis during and after TAE. The hepatic metastatic lesion of CT findings was decreased after TAE. Although blood pressure showed a transient hypertension (180/100 mmHg) after every TAE, it returned rapidly to normal. The patient experienced transient abdominal pain, nausea, and loss of appetite after every TAE; however, those symptoms were readily controlled by conventional medications. Slight elevation of liver transaminases was recognized but returned to normal range within 3 weeks. No other major side effects were seen with TAE. While plasma and urinary level of catecholamines were unchanged, plasma chromogranin A (CgA) level was significantly decreased. These results suggest that TAE is a useful treatment for hepatic metastases. Plasma CgA level is a useful marker in the treatment of malignant pheochromocytoma.

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Mitiglinide is novel class of rapid-acting insulin secretagogues, which have been widely used alone or in combination with other oral hypoglycemic drugs to improve postprandial hyperglycemia in early type 2 diabetes. While mitiglinide enhances postprandial requirement of insulin, the efficacy of mitiglinide combined with insulin has yet to be established. We investigated the efficacy of mitiglinide combined with insulin glargine, the first soluble insulin analog that has a flat and prolonged effect. After control with the intensive regimen (daily aspart insulin and glargine), 30 inpatients with type 2 diabetes were switched to premeal mitiglinide combined with once daily insulin glargine (mitiglinide regimen), and daily profiles of blood glucose level were compared under each regimen. Fifteen patients showed similar control of hyperglycemia with mitiglinide regimen and intensive insulin regimen, assessed by M value (<32), while the remaining 15 showed worsening under the mitiglinide regimen. The patients who were well controlled with mitiglinide regimen were significantly younger (51.9 ± 16.0 years, p<0.005) and heavier (body mass index: 25.7 ± 3.3 kg/m², p<0.05) than those who were not (67.9 ± 8.7 and 23.0 ± 3.1, respectively). Moreover, insulin doses of aspart per body weight were significantly fewer in effective group than in ineffective group. Duration of diabetes was shorter in the effective group, albeit insignificantly. Previous treatment before starting intensive insulin regimen, such as insulin and sulfonylurea, was not different between the two groups. Our results suggest that mitiglinide plus insulin glargine combination therapy is useful for lowering both fasting and postprandial hyperglycemia in a subpopulation of type 2 diabetes. The long-term effects of such treatment need to be established in future studies.

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The present study was conducted to compare the effects of exogenous follistatin and activin A on liver regeneration in 90% hepatectomized rats. Intraportal administration of follistatin markedly accelerated liver regeneration, and nuclear BrdU labeling and liver regeneration rate were greatly increased by follistatin. In contrast, administration of activin A attenuated liver regeneration. After 120 h of 90% hepatectomy, histological analysis showed that the hepatic architecture was restored in control and activin-treated rats. However, it was not restored in follistatin-treated rats. The serum bilirubin levels were significantly increased in follistatin-treated rats, and the serum glucose level was significantly lower in follistatin-treated rats. Although follistatin markedly accelerated liver regeneration, it reduced the function of the remnant liver. Treatment with activin A instead may be beneficial to support liver regeneration after massive hepatectomy.

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We report two cases of insulinoma in advanced age patients considered unsuitable for surgery, in whom single daily doses of octreotide successfully improved hypoglycemia and hyperinsulinemia. The biological half-life of octreotide is about 100 min, hence it is customary to use two or three administrations per day to prevent hypoglycemia in insulinoma patients. The first case was a 76-year-old woman who presented with hyperinsulinemic hypoglycemia. Computed tomography (CT) and magnetic resonance imaging did not identify a tumor in the pancreas but a 1.5-cm tumor was found in the pancreatic body on abdominal angiography and selective arterial calcium stimulation and hepatic venous sampling (ASVS) were compatible with insulinoma. The patient refused surgery, but was successfully treated with octreotide at 50 μg subcutaneous injection once daily. Since the treatment was started (1 year), she has not suffered hypoglycemia. Case 2 was an 85-year-old woman who presented with hyperinsulinemic hypoglycemia. CT identified a 1.5-cm tumor in the pancreatic uncus, but she was considered unsuitable for surgery due to advanced age, obesity and cardiopulmonary dysfunction. Octreotide at 100 μg subcutaneous injection once daily prevented further hypoglycemic attacks, but two months later, postprandial plasma glucose was elevated. Octreotide was gradually reduced to 50 μg once daily. Three years have passed since the treatment without any hypoglycemic attack. Successful treatment with octreotide once daily could be due to old-age-related slow metabolism and could be potentially considered as the treatment of choice for elderly patients with insulinoma especially those considered unsuitable for surgery.

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Core binding factor α1 (Cbfa1) is a member of the runt family of transcription factors, which appears to play a pivotal role in regulating the differentiation of osteoblastic precursors and the activity of mature osteoblasts. Total flavonoids of Herba epimedii (HEF) is a recognized bone anabolic agent, but there is lack of reports on the modulation of Cbfa1 expression by HEF. Here we investigated the effect of HEF on Cbfa1 expression in the bone of ovariectomized (OVX) rats. HEF could increase the expression of Cbfa1 mRNA in the bone of ovariectomized rats in a dose-dependent manner. Furthermore, the high dose HEF (160 mg/kg) administered for 12 weeks in vivo stimulated osteocalcin expression. These findings suggest that Cbfa1 is required for mediating the anabolic effects of HEF.

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A 54-year-old man was admitted to our hospital for evaluation of hypoglycemia. He had frequent episodes of loss of concentration before dinner. The ratio of IRI to plasma glucose (PG) was 0.8-1.0. Abdominal CT revealed no pancreatic tumor, and angiography of splenic artery showed no definite tumor stain within the pancreas. Based on the results of selective arterial calcium stimulation and hepatic venous sampling (ASVS), the provisional diagnosis was a small insulinoma in the pancreatic body. The patient underwent subtotal distal pancreatectomy. However, histopathological and immunohistochemical examinations of the resected tissue showed hypertrophy of islets of Langerhans islands and β cells around pancreatic ducts. The final diagnosis was adult-onset nesidioblastosis. Postoperatively, the patient continued to exhibit hyperinsulinemia and nighttime hypoglycemia. Octreotide, voglibose and diet therapies failed to improve the nocturnal hypoglycemia. However, treatment with diazoxide at a starting dose of 200 mg/day resulted in immediate amelioration of nocturnal hypoglycemia. This is the first Japanese adult case of nesidioblastosis treated successfully with diazoxide. This case report suggests that diazoxide may be effective for adult-onset nesidioblastosis in a manner similar to that described for pediatric cases.

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Several measurement systems are used for LH, FSH, and PRL in Japan, but the comparison of the measured values is difficult in some cases. In this study, we compared the measured values of 3 types of measurement systems widely used in Japan, SPAC-S, ARCHITECT, and Centaur, in females with a normal menstrual cycle and with various ovulatory disorders. Variant LH was discriminated by the criterion, SPAC-S LH/ARCHITECT LH ratio <0.5. Excluding the variant LH, the correlation of the measured LH values among the measurement systems was high, 0.94-0.99, and the value measured by ARCHITECT LH and Centaur LH was slightly higher than that measured by SPAC-S LH. As for FSH, the correlation was also high, 0.94-1.00, and the value measured by ARCHITECT FSH and Centaur FSH was slightly lower than that measured by SPAC-S FSH. The important judgment criterion of polycystic ovary syndrome (PCOS), a high level of LH relative to FSH, has been set to 1.0 or higher LH/FSH using SPAC-S. When the regression line of the LH/FSH ratio among the measurement systems was investigated, it can be said that 1.25 or higher by ARCHITECT and 1.40 or higher by Centaur are appropriate for the judgment criteria of a high level of LH relative to FSH. As for PRL, the correlation was high, 0.96-0.99, but the value showed large differences among the systems. For the diagnosis of hyperprolactinemia, the higher limit of the normal range may be 15 ng/mL for SPAC-S, 30 ng/mL for ARCHITECT, and 24 ng/mL for Centaur.

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We report a rare case of ACTH-independent macronodular adrenal hyperplasia (AIMAH) with primary hyperparathyroidism (PHPT). A 57-year-old woman was admitted to our hospital for further examination of secondary hypertension and bilateral adrenal macrotumors. Midnight serum cortisol elevation with undetectable plasma ACTH, increased 24-hour urinary free cortisol excretion, and loss of the normal circadian rhythm in cortisol secretion established the diagnosis of Cushing's syndrome. Total resection of the enlarged left adrenal gland was performed with subsequent steroid replacement. Her general condition improved but serum calcium level increased 3 weeks after surgery. PHPT was diagnosed on the basis of endocrinological examination, although imaging studies failed to detect parathyroid lesion. In summary, we believe this to be the first report of a case of AIMAH with PHPT.

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Hyperhomocysteinemia is an independent risk factor for coronary, peripheral and cerebrovascular diseases. Moderately elevated total homocysteine (tHcy) levels have been reported in patients with overt hypothyroidism. Plasma tHcy concentration is affected by several physiological factors and is elevated under conditions of impaired folate and cobalamin status and in renal failure. The aim of this study was to assess plasma tHcy concentrations and to evaluate the role of potential determinants of plasma tHcy levels in hypothyroid patients. Fasting plasma tHcy, serum homocysteine-related vitamins folate and vitamin B₁₂, serum cystatin C (CysC) and creatinine, were determined in 22 hypothyroid patients and compared with 25 healthy control subjects. Creatinine clearance (CCr) was calculated using the Cockroft-Gault formula. Plasma tHcy levels were determined by HPLC with fluorescence detection and serum CysC by automated particle enhanced immunoturbidimetry. Plasma tHcy, creatinine levels were significantly higher, and serum CysC levels, and creatinine clearance values were lower in hypothyroid patients than in control subjects. Folate levels were lower in hypothyroidic group compared to the control group. There were no differences in vitamin B₁₂ levels between hypothyroid and control groups. Positive correlation was noted between tHcy and creatinine levels in hypothyroid patients (r = 0.596); however, an inverse correlation was found between tHcy and folate levels (r = -0.705) in hypothyroid patients. In conclusion, tHcy was increased in hypothyroidism, and this increase was more strongly associated with changes in serum folate than in serum creatinine and CysC, suggesting an altered folate status.

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We reviewed the cases of 32 patients with growth hormone (GH)-secreting macroadenoma who underwent short-term octreotide treatment before transsphenoidal surgery to determine which types of adenoma the preoperative treatment were sensitive and whether predictors of tumor shrinkage could be identified. The effects of preoperative octreotide treatment, endocrinologic effect and effect on tumor volume in 32 patients were evaluated retrospectively in relation to tumor features on magnetic resonance images and responses to endocrinologic challenge tests. At a daily dose of 300 μg for 2-3 weeks, octreotide reduced serum GH and insulin-like growth factor-1 (IGF-1) levels to 31.9 % and 51.6% of pretreatment values, respectively, and led to a mean tumor volume of 68% of pretreatment volume in 52% of the patients. The endocrinologic effect and the effect on tumor volume were larger in Knosp grades 0-2 than in Knosp grades 3-4. Tumor shrinkage occurred significantly more often among patients that had a good response to both octreotide and bromocriptine challenge tests. For surgical removal of the tumor, the effect of reducing tumor to 68% of pretreatment volume will be beneficial for the macroadenomas of Knosp grades 1-2. Preoperative short-term octreotide treatment is effective for GH-secreting macroadeomas of Knosp grades 1-2 and a good response to both octreotide and bromocriptine challenge tests is a predictor of subsequent tumor shrinkage. These results will lead to more effective selection of patients for preoperative octreotide treatment.

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Inflammation and thrombogenesis have been suggested as possible causes for cardiovascular events in patients suffering from metabolic syndrome (MS). The primary objective of this study was to determine the relationship between red blood cell (RBC) or white blood cell (WBC) subtypes and MS. The secondary objective was to reveal any gender differences inherent to this association. Body mass index (BMI), blood pressure, serum high-density lipoprotein cholesterol, triglycerides, and glucose were measured. The numbers of WBC subtypes and RBCs were determined in healthy adults. In male subjects, the numbers of total leukocytes, neutrophils, and lymphocytes was elevated in the MS patients (P<0.05). In the male subjects, the numbers of total leukocytes, neutrophils, and lymphocytes were elevated in accordance with the metabolic component count (P<0.05). RBC, monocyte, eosinophil, and basophil counts did not differ in accordance with metabolic component counts (r = 0.406, r = 0.304, r = 0.366; P<0.05). In the female subjects, we determined there to be no differences in the numbers of RBC and WBC subtypes in the MS patients, in accordance with metabolic component counts. The numbers of total leukocytes, neutrophils, and lymphocytes were elevated in the male MS subjects in this study, and these counts increased in accordance with the metabolic component counts. In the female subjects in this study, we determined there to be no association between RBC and WBC subtype counts with MS.

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We report a case with insulinoma diagnosed and localized preoperatively using a combination of contrast-enhanced ultrasonography (CEUS) and arterial stimulation and venous sampling (ASVS). A 76-year-old woman was admitted to our hospital because of hypoglycemic attacks, delirium, and dementia. Fajans' ratio, Grunt's ratio, and Turner's ratio, which are reported to be indexes for endogenous hyperinsulinemia in insulinoma, were all negative. Imaging tests, including computed tomography, magnetic resonance imaging and angiography, failed to detect any abnormalities. CEUS showed a small low echoic lesion in the pancreatic body with blood flow and ASVS showed that the insulin levels in the hepatic vein were extremely increased by calcium injection to the splenic artery, indicating an insulinoma in the pancreatic body preoperatively. An open intra-abdominal operation was performed and an insulinoma was confirmed in the pancreatic body. Enucleation of tumor was undertaken and symptomatic hypoglycemia improved.

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The aim of this study was to develop an assay to selectively detect high-affinity components among TRAb. Using an rhTSHR-coated tube system, a 1 step TRAb assay method was developed that included 1) co-incubation with ¹²⁵I-bTSH, 2) a 50 μl serum sample, 3) an increased incubation volume (450 μl), and 4) a 1 hour incubation time. Sixty-one TRAb positive Graves' sera were studied. When the regular TRAb assay (Reg) results were quantitatively compared to the 1 step assay (1 step) results, certain dispersions and overestimations using the latter were seen. Further, some 1 step positive results were observed in the low Reg range. Overestimations were considered mostly due to the differences between TRAb standard and patients' serum TRAb in the binding competition against co-incubated ¹²⁵I-bTSH, which was shown from a modified assay mimicking the 1 step conditions. Therefore, the 1 step results were decided to be expressed by % inhibition against ¹²⁵I-bTSH. As for data dispersions, TRAb absorptions during the regular 1^st incubation were studied. Individually, the absorption rates varied from 11 to 69%, and higher absorptions were observed in lower Reg range, especially in those negative by the 1 step. Observed 1 step positive results in the low Reg range were of interest, and 1 step/Reg ratios were calculated. The ratios with 1 step negative samples were significantly lower than those of 1 step positive samples. In conclusion, the 1 step assay was proved to detect a particular and biologically active TRAb, especially in those with low TRAb. The clinical significance of the 1 step results should be of future interest.

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