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Objective: To determine whether there is an age-related difference in the therapeutic response to antithyroid drugs in hyperthyroid Graves' disease. Design: Retrospective analysis of treatment duration and recurrence rate. Patients: Two hundred and twenty-two patients who have triiodothyronine-suppressible thyroids within 4 years of methimazole treatment. Measurements: Serum thyroid hormone levels, serum thyrotropin receptor antibody titer, and thyroidal radioiodine uptake. Main results: A longer period of methimazole treatment was needed to normalize serum thyroid hormone levels and to restore normal thyroidal triiodothyronine suppressibility in young than in aged patients. There was an average 10-month lag between normalization of thyrotropin receptor antibody titer and restoration of thyroidal triiodothyronine suppressibility in both young and aged patients. Recurrence after discontinuation of methimazole was more frequent in young than in aged patients. Conclusions: Aged patients with hyperthyroid Graves' disease show a more favorable response to antithyroid drugs than young counterparts.

Glucose induces biphasic insulin secretion by the islet beta-cell. Based on recent knowledge on glucose signaling in the beta-cell, the underlying mechanisms for this biphasicity could be envisaged as follows. Glucose-induced elevation of cytosolic free Ca(2+) concentration, which is due to the electrophysiological events that originate in closure of the ATP-sensitive K(+) (K(ATP)) channel, most likely triggers the first phase. The second phase is produced by gradual augmentation and potentiation of Ca(2+)-triggered insulin release by the K(ATP) channel-independent, nonionic signals. Protein acylation may be involved in the nonionic signaling. In patients lacking functional K(ATP) channels, however, the first phase of glucose-induced insulin secretion is clearly retained, casting doubt on the simplistic view outlined above. In this pathological condition, the K(ATP) channel-independent, most likely nonionic, glucose action alone is sufficient for the first-phase response.

We present the case of a 65-year-old man with a pancreatic nonfunctioning neuroendocrine tumor causing main pancreatic duct obstruction that presented as excessive hyperglycemia. We considered the tumor elicited worsening of diabetes in this case, and we performed review of the relevant literature.

The relationship between insulin sensitivity (Si) and insulin secretion (β) was analyzed in 533 health examinees. The subjects underwent a 75 g oral glucose tolerance test, with plasma glucose (PG) and immunoreactive insulin (IRI) determined at fasting, 30 min and 120 min, and were classified according to the current criteria as normal glucose tolerance (NGT, n=328), non-diabetic hyperglycemia (NDH, n=113) including impaired fasting glucose and impaired glucose tolerance, and diabetes mellitus (DM, n=72). NGT was subdivided by fasting PG (FPG) tertile, ≤4.9, 5.0-5.4 and 5.5-6.0 mM, into NGT(FPG1), NGT(FPG2) and NGT(FPG3), or by body mass index (BMI) tertile, ≤21.8, 21.9-24.4 and ≥24.5 kg/m², into NGT(BMI1), NGT(BMI2) and NGT(BMI3). As an index of Si and β, Matsuda index=10,000/sqrt[FPG·FIRI·2hPG·2hIRI] and δIRI₀₋₃₀/δPG₀₋₃₀, were employed respectively: FIRI, 2hPG and 2hIRI denote fasting IRI, 2h-post glucose PG and IRI, respectively. Correlation between Si and β was evaluated by Spearman's rank correlation and the parameters for [β]=a·[Si](b) were obtained by standardized major axis (SMA) regression. Si-β correlation was strongest in NDH (Spearman's rho=-0.546, SMA regression r²=0.277), intermediate in DM (rho=-0.432, r²=0.193) and weakest in NGT (rho=-0.201, r²=0.039). Spearman's rho for the Si-β correlation was significantly lower in NGT than in NDH (p=0.003). Si-β correlation was significant in NGT(FPG3), NGT(FPG2) and NGT(BMI3), but not in NGT(FPG1), NGT(BMI2) and NGT(BMI1). The slope, b, was -1.184˜-1.530 without significant differences between any groups. In conclusion, the hyperbolic Si-β correlation was weaker in NGT than in NDH and absent in NGT subjects belonging to the lowest FPG or BMI tertile.

A 29-year-old female patient presented with shock and dyspnea due to heart failure and pulmonary edema. Echocardiography indicated excessive contraction limited to the left ventricular apex and akinesis of the basal and middle ventricle, which were confirmed by emergency left ventriculography. The finding was diagnostic of inverted Takotsubo cardiomyopathy. An abdominal computed tomography scan showed a tumor in the left adrenal gland with a central low-density area, and the plasma and urinary catecholamines were strikingly elevated. Taken together, these findings suggested the presence of a hemorrhagic pheochromocytoma. A myocardial biopsy in the very acute stage on the day of admission revealed neutrophilic infiltration and contraction-band necrosis, which was indistinguishable from the previously reported pathology in the acute phase of idiopathic Takotsubo cardiomyopathy without pheochromocytoma. The diagnosis of pheochromocytoma in this case was confirmed 7 weeks later by surgical removal of the left adrenal gland with massive hemorrhage at the center of the pheochromocytoma. The marked similarity of the endomyocardial pathology between this case and cases with idiopathic Takotsubo cardiomyopathy strongly points to catecholamine excess as a common causality for Takotsubo cardiomyopathy with or without pheochromocytoma.

Inflammation is a hallmark of many diseases, such as atherosclerosis, chronic obstructive pulmonary disease, arthritis, infectious diseases, and cancer. Although steroids and cyclooxygenase inhibitors are effective antiinflammatory therapeutical agents, they may cause serious side effects. Therefore, developing unique antiinflammatory agents without significant adverse effects is urgently needed. Vinpocetine, a derivative of the alkaloid vincamine, has long been used for cerebrovascular disorders and cognitive impairment. Its role in inhibiting inflammation, however, remains unexplored. Here, we show that vinpocetine acts as an antiinflammatory agent in vitro and in vivo. In particular, vinpocetine inhibits TNF-α–induced NF-κB activation and the subsequent induction of proinflammatory mediators in multiple cell types, including vascular smooth muscle cells, endothelial cells, macrophages, and epithelial cells. We also show that vinpocetine inhibits monocyte adhesion and chemotaxis, which are critical processes during inflammation. Moreover, vinpocetine potently inhibits TNF-α- or LPS-induced up-regulation of proinflammatory mediators, including TNF-α, IL-1β, and macrophage inflammatory protein-2, and decreases interstitial infiltration of polymorphonuclear leukocytes in a mouse model of TNF-α- or LPS-induced lung inflammation. Interestingly, vinpocetine inhibits NF-κB–dependent inflammatory responses by directly targeting IKK, independent of its well-known inhibitory effects on phosphodiesterase and Ca 2+ regulation. These studies thus identify vinpocetine as a unique antiinflammatory agent that may be repositioned for the treatment of many inflammatory diseases.

In 77 untreated patients (16 males and 61 females, aged 12 to 65 years) with hyperthyroid Graves' disease, and in 107 control subjects (36 males and 71 females, aged 13 to 78 years), blood urea nitrogen (BUN), serum creatinine (Scr) levels, and BUN to Scr ratios (BUN/Scr) were determined. In 53 patients, the determinations were performed before treatment and after restoration of euthyroidism by treatment with an antithyroid drug. In addition, in seven untreated patients and seven normal subjects, renal clearances of creatinine (Ccr), urea nitrogen (Cun), inulin (Cin), and p-aminohippurate (CPAH) were also determined. The distal tubule delivery of chloride (DTD) and the distal fractional chloride reabsorption (DFCR) were also measured in these subjects: DTD = (CH2O + Ccl)/Cin x 100, and DFCR = CH20/(H20 + Ccl) x 100, where CH20 and Ccl stand for clearances of H2O and chloride, respectively. BUN was significantly elevated, while Scr was significantly depressed, in untreated patients with hyperthyroid Graves' disease. Accordingly, the BUN/Scr was markedly elevated. Restoration of euthyroidism accompanied the normalization of all these abnormalities. Ccr and Cun were significantly elevated, but Cin (glomerular filtration rate [GFR]) was slightly, but insignificantly, elevated in the patients. As a result, the ratios Ccr/Cin and Cun/Cin were significantly greater in the patients than in controls (Ccr/Cin, 1.42 v 1.00; Cun/Cin, 0.92 v 0.68). The amounts of urinary creatinine and urea nitrogen (UN) excretion were decreased and increased, respectively, and DTD was significantly depressed, but DFCR was unchanged in the patients. We conclude that BUN is elevated, Scr is depressed, and the BUN/Scr is increased in hyperthyroidism.(ABSTRACT TRUNCATED AT 250 WORDS)

Transient exposure of rat pancreatic B-cell to 50 mM K+ ([K+50]) makes exocytosis unresponsive to further depolarization, i.e., stimulation with 100 mM K+ or 1 uM glyburide, which closes the ATP-sensitive K+ (K+ATP) channel, simultaneously with [K+50] does not produce any greater insulin secretion compared with [K+50] alone. In sharp contrast, 16.7 mM glucose ([G16.7]) applied simultaneously with [K+50] elicits an insulin response markedly greater than that produced by [K+50] alone, which is not attenuated by 100 uM diazoxide, an inhibitor of K+ATP channel closure. [G16.7]-Induced Insulin secretion at the basal K+ concn of 4.7 mM was greatly (93%) suppressed by 100 uM diazoxide. Insulin secretion induced by [K+50] plus [G16.7] ([K+50 + G16.7]) was markedly suppressed (70%) by 1 uM nifedipine, a Ca2+-channel blocker and was completely abolished by 2 mM 2-cyclohexen-1-one, which reportedly decreases reduced glutathione level and blocks glucokinase. This finding indicates that insulin release induced by [K+50 + G16.7] is not due to leakage produced by toxic stimuli but to activation of exocytosis. When graded concentrations (25 and 50 mM) of K+ were applied simultaneously with [G16.7] in the presence of 100 uM diazoxide, insulin response was clearly dependent on K+ concentration, indicating that the physiological range of membrane depolarization also activates the glucose-responsive effector. Membrane depolarization/Ca2+ influx directly stimulates hormone exocytosis on one hand and activates the K+ATP channel-independent glucose-responsive effector or effectors on the other in the B-cell. The nature of the glucose-responsive effector or effectors remains to be established.

The physiology of atrial naturiuretic peptide (ANP) secretion was studied in normotensive subjects and hypertensive patients both young and old. Basal plasma ANP concentration was least in young normotensives, intermediate in old normotensives and young hypertensives, and highest in old hypertensives. Nifedipine, a known stimulator of ANP secretion, acutely increased plasma ANP in young and old normotensive subjects but not in young hypertensive patients and half of the old hypertensive patients. Increase in serum ANP level in response to nifedipine did not augment its hypotensive effect. However, the increase of aldosterone in response to nifedipine-induced rise in plasma renin activity (PRA) seemed to be suppressed by elevated ANP.

Patients with autoimmune insulin antibody are characterized by hypoglycemic attacks and antibodies to insulin in serum without prior insulin administration. In the present report, a patient with hypoglycemia due to autoimmune insulin antibody associated with primary empty sella syndrome and polymyositis appeared to have high urinary immunoreactive insulin (IRI) in the face of normal urinary C peptide. Consequently, the urinary IRI/C peptide ratio was apparently high. The amelioration of hypoglycemic attacks and polymyositis by prednisolone treatment was accompanied by the disappearance of the antibodies and complete normalization of the urinary IRI and IRI/C peptide ratio. No comparable rise in the urinary IRI and IRI/C peptide ratio was observed in the patients with other disorders studied. Glucose clamp and glucose tolerance study showed decreased sensitivity to exogenous or newly secreted insulin, prolonged half disappearance time of serum insulin, and normal disappearance of blood glucose. These results were consistent with the idea that autoantibodies buffered the effect of exogenous or newly secreted insulin and maintained a relatively constant level of serum free insulin which was not high enough when a large amount of glucose was loaded, but was too high after prolonged fasting, which eventually caused hypoglycemic attacks.

To evaluate the role of adrenal androgens in the development of arteriosclerosis, serum dehydroepiandrosterone sulfate (DHEAS), dehydroepiandrosterone (DHEA), aortic calcification and pulse wave velocity (PWV) were measured in 69 males and 119 females without overt cardiovascular disease. The steroids decreased with age in both sexes, and the reduction was significantly steeper in younger (or = 40 years) than in older (40 years) subjects only in females. When adjusted for age, the steroids were significantly lower in subjects with aortic calcification than in those without it, and the PWV was significantly slower in the latter. Adrenal androgens appear to retard the development and/or progression of arteriosclerosis.

Mastoparan, a tetradecapeptide purified from wasp venom, stimulates insulin and glucagon release by rat pancreatic islets in a dose-related manner. In perifusion experiments, mastoparan produces monophasic hormone release, which ceases within 10 min of removal of the peptide. After exposure of the isles to mastoparan, glucose-induced insulin release is clearly retained. In incubation experiments, mastoparan-induced insulin release is greatly blocked by pretreatment of the islets with pertussis toxin or neomycin (inhibitor of phosphoinositide turnover) or by lowering the ambient temperature to 17 C. Pretreatment of the islets with nifedipine (calcium channel blocker), H-7 (inhibitor of A- and C-kinase), somatostatin, or divalent cation-free medium does not affect the response to mastoparan. Pretreatment with parabromophenacylbromide (phospholipase-A2 inhibitor) does not block the response induced by a high concentration of (58 microM) mastoparan. The peptide does not stimulate insulin synthesis during 30 min of incubation. Mastoparan raises the cytosolic free Ca2+ concentration, measured by fura-2, in isolated islet cells at normal (1.9 mM) and very low (6.5 microM) extracellular Ca2+ concentrations. Intravenous administration of mastoparan in rats causes a significant elevation of both insulin and glucagon. Together with the previous data, we conclude that mastoparan stimulates islet hormone release through a temperature-dependent process mediated by pertussis toxin-sensitive GTP-binding protein(s). Activation of phospholipase-C and liberation of intracellular Ca2+ are likely to be coupled to exocytosis. Ca2+ influx through the Ca2+ channel and protein kinase-A and -C appear not to be involved in mastoparan's hormone-releasing action. Phospholipase-A2 may be involved in the hormone release induced by low, but not high, concentrations of the peptide.

Among 436 patients with hypertension unrelated to any renal lesion, renovascular damage, pheochromocytoma, Cushing’s syndrome or hyperthyroidism, 15 patients had low plasma renin activity (PRA) and el

Hyperthyroidism due to Graves' disease is more prominent in older patients than was originally thought. Aged patients with this disorder have characteristic clinical and hormonal features that are different from those in younger patients. Thus, Graves' disease in aged patients is not merely a milder form of the disease seen in youth, but is qualitatively different in many aspects. Owing in part to incomplete understanding of the etiology of Graves' disease, the pathophysiologic reasons for these differences are unknown.

急性リウマチ熱に急性腎不全を合併し, 腎不全発症時の原因として急性糸球体腎炎の併発が考えられた成人例を報告する. 症例は23歳の男性. 感冒様症状の約10日後, 発熱, 関節痛, 呼吸困難のため入院となった. 入院時, 軽度の高血圧, 扁桃腫大, 全身の関節腫脹がみられた. 検尿では蛋白尿, 血尿, 顆粒円柱を認め, 血液検査では高度の白血球増多, 血沈値亢進, CRP強陽性, ASO価上昇, 軽度の腎機能障害を認めた. 扁桃炎に対し抗生物質が投与されたが, 心膜摩擦音が聴取されるようになり, 腎不全も進行した. 胸部X線, 心電図, 心エコー検査で心膜炎, 心筋炎の所見を認めたためJonesの診断基準により急性リウマチ熱と診断し, これに急性腎不全が合併したものと考えられた. 血液透析, ペニシリン系抗生物質およびステロイド剤の投与により両病態とも軽快した. 第30病日の腎生検ではメサンギウムのごく軽度の拡大と, 糸球体への好中球の軽度浸潤が主体であったが, 一部の糸球体に半月体形成を伴った硝子化像およびその周囲の高度の線維化, 細胞浸潤が認められ, 急性腎不全発症時の原因として急性糸球体腎炎の併発が示唆された.

Effects of long-acting somatostain analogue (SMS 201-995) on plasma corticotropin (ACTH) and corticotropin-releasing hormone (CRH) levels were studied in a patient (63-year-old woman) with ectopic ACTH-producing tumors associated with type I multiple endocrine neoplasia (MEN-I). The patient had undergone bilateral adrenalectomy. Plasma CRH, as well as plasma ACTH, beta-endorphin and alpha-MSH, increased. The hormone levels were dramatically decreased by acute administration of SMS 201-995. Moderately higher doses of dexamethasone (0.05 or 0.1 mg/kg a day) did not decrease plasma CRH or ACTH. An extremely high dose of dexamethasone (0.2 mg/kg a day), however, decreased plasma ACTH, but failed to decrease plasma CRH. Acute administration of SMS 201-995 further lowered the level of plasma ACTH even in this condition. In addition to the decrease in ACTH, SMS 201-995 decreased plasma CRH. Chronic administration of SMS 201-995 continuously decreased plasma CRH, ACTH and beta-endorphin. The decrease in these hormone concentrations accompanied the disappearance of hyperpigmentation. These results suggested that SMS 201-995 inhibits hypersecretion not only of ACTH but also of CRH, and that the agent is therapeutically useful in normalizing the hypersecretion of these hormones.

To assess the regression of cardiac hypertrophy during long-term (12 years) antihypertensive treatment, the following parameters were determined in 93 patients with essential hypertension: SV1 + RV5 by electrocardiography (ECG), and septal wall (SW) and posterior wall (PW) thickness by echocardiography (UCG). The patients were treated with a thiazide diuretic alone (group 1), thiazide + beta-blocker (group 2), thiazide + methyldopa or nifedipine (group 3) or nifedipine or methyldopa alone (group 4). The blood pressure decreased gradually within 6 months of treatment. According to ECG, regression of left ventricular hypertrophy occurred during the initial 7 years in all groups, whereas in the subsequent 5 years, statistically significant regression was found only in the patients treated with thiazide + other drugs (group 3). By UCG, which was taken only at the 7th and 12th year, regression was detectable during the last 5 years in all groups. The apparent incidence of regression of hypertrophy was lower in the thiazide-alone group (group 1) than in the thiazide + beta-blocker group (group 2), most likely due to mild hypertension in group 1. A cardiovascular accident (nonfatal myocardial infarction) occurred only in 1 patient. We conclude that during long-term antihypertensive treatment, persistent, progressive reversal of cardiac hypertrophy takes place.

Background: Immediate and accurate differential diagnosis is critically important for the patients who present acute onset of chest and/or back pain. We have noticed that regions of decreased contrast enhancement existed within the myocardial wall of the patients with acute coronary syndrome (ACS) on conventional computed tomography (CT) images, performed to differentiate other acute thoracic diseases (e.g. aortic dissection, pulmonary embolism). This study was designed to utilize these features for the differential diagnosis of ACS. Methods: The study population consisted of 95 consecutive patients who required enhanced CT for the differential diagnosis of acute chest discomfort at the emergency room. Using the representative apical four-chamber view, the left ventricular (LV) wall was divided into the following 6 segments: 1) basal septum, 2) mid septum, 3) apex, 4) mid lateral, 5) basal lateral and 6) basal posterior. A CT number was measured at each segment, and was then fitted into either of the following formula to calculate a segmental perfusion abnormality (SPA) index based on the existence of visually-apparent low density segments (VALDS): 1) In case of VALDS presence: average CT numbers of VALDS/average CT number of the rest normal segments × 100 (%), 2) in case of VALDS absence: the minimum CT number/average CT number of the rest 5 segments × 100 (%). The SPA index was compared between the two groups, one with ACS and another without ACS, both confirmed by coronary angiography. Results: Forty-five patients (47.4%) were eventually diagnosed as ACS by coronary angiography. Importantly, the SPA index was significantly smaller in the ACS group compared to the non ACS group (48.7±17.2% vs 85.5 ± 7.1%, p Conclusions: The SPA index, a novel CT-based diagnostic approach for the non-invasive visualization of the ischemic LV wall, is confirmed to be easy and accurate method to differentiate ACS among the various patients who present acute chest or back pain.

To examine retinopathy and nephropathy in elderly patients with diabetes mellitus (DM) under intensive multifactorial DM control.Six-year interventional observation study.Multicenter study including four hospitals.Four hundred thirteen elderly (or = 65) patients with type 2 DM attending each hospital for 1 year or longer; those receiving hemodialysis or with uncured malignancy were excluded.Development, worsening, and improvement of retinopathy and nephropathy and respective risk factors.The mean baseline hemoglobin (HbA1c), blood pressure (BP), and total cholesterol were 6.8%, 137/74 mmHg, and 5.13 mmol/L, respectively. Retinopathy developed in 45 of 168 (27%) patients and, of 63 with nonproliferative retinopathy, worsened and improved in 11 (17%) and 23 (37%), respectively. Nephropathy developed in 53 of 227 (23%) patients and improved in 13 of 51 (25%) having it baseline. The mean change in glomerular filtration rate (DeltaGFR, baseline GFR-GFR at the end of the study period) in those with nephropathy at baseline was 21.5 mL/min. HbA1c was related to development of retinopathy (P=.001, odds ratio (OR)=1.91), and serum creatinine (P=.03, OR=1.02), systolic BP (SBP) (P=.03, OR=1.22), and prior stroke (P=.005, OR=3.21) were related to development of nephropathy. In patients with nephropathy at baseline, SBP (P=.03, Spearman's rho (rho)=0.310), total cholesterol (P=.01, rho=0.361), and low-density lipoprotein cholesterol (P=.03, rho=0.322) were correlated with DeltaGFR.In elderly patients under intensive control for DM, the outcome of microangiopathy is favorable. Modifiable risk factors were hyperglycemia for development of retinopathy and hypertension and hypercholesterolemia for development or worsening of nephropathy; prior stroke was an unmodifiable risk factor for development of nephropathy.

In this study we confirmed our previous findings on the importance of IgE in Graves' disease and further investigated the relationships existing among Graves' disease, IgE, and interleukin-4. Two hundred and thirty-two newly diagnosed Graves' disease patients were treated with methimazole for 2 years, and were classified into 3 groups according to their response to the therapy. Incidence of IgE elevation (IgEor =170 IU/ml) before treatment was lowest, 23.8%, in the group who achieved remission without recurrence, while it was 41.7% in the group who achieved remission but recurrence occurred within 4 years. Incidence of IgE elevation before treatment was highest, 60.7%, in the group who failed to achieve remission, significantly higher than that of the group without recurrence. Incidence of IgE elevation before treatment in all these patients of Graves' disease were 35.3%, significantly higher than those of Hashimoto's thyroiditis (17.5%) and of simple goiter (7.0%). Serum IL-4 levels before treatment were significantly higher in the patients of Graves' disease with IgE elevation than in those without IgE elevation. Serum T4 concentration and TSAb titration before treatment were also significantly higher in elevated IgE group than in normal IgE group. These results support our previous findings and suggest that IL-4 may play important roles in the elevation of IgE, TBII, and TSAb in patients of Graves' disease, and that IL-4 and IgE may be involved in the development, progression, and maintenance of Graves' disease.

Background Coronary artery spasm plays an important role in the pathogenesis of vasospastic angina, and contributes to the development of several acute coronary syndromes. Endothelial nitric oxide synthase (ecNOS) catalyzes the synthesis of nitric oxide, which regulates vascular tone, and may be related to coronary vasospasm. The present study investigated whether coronary spasm is related to particular polymorphisms of the ecNOS gene. Methods and Results Spasm provocation by serial infusions of acetylcholine was performed on 165 patients who were clinically suspected of having angina. In both study patients and healthy controls (n=400), genomic polymorphisms of the ecNOS gene were determined by using polymerase chain reaction. Quantitative luminal diameter measurements of the 3 major coronary arteries were initially obtained before and after acetylcholine injection, and then after isosorbide dinitrate injection, by using a computer-assisted analysis system. Logistic multiple regression analysis identified the a/a or a/b genotype in intron 4 of ecNOS (NOS4a: p=0.0431, odds ratio (OR) 2.43) and diabetes mellitus (p=0.0060, OR 4.88) as significant predictors of coronary spasm. In the patients with NOS4a, both the induced and spontaneous contractions were augmented. Conclusion The present study results indicated that NOS4a could be a good marker for coronary artery spasm. (Circ J 2006; 70: 409 - 413)

In response to biological and mechanical injury, or in vitro culturing, vascular smooth muscle cells (VSMCs) undergo phenotypic modulation from a differentiated “contractile” phenotype to a dedifferentiated “synthetic” one. This results in the capacity to proliferate, migrate, and produce extracellular matrix proteins, thus contributing to neointimal formation. Cyclic nucleotide phosphodiesterases (PDEs), by hydrolyzing cAMP or cGMP, are critical in the homeostasis of cyclic nucleotides that regulate VSMC growth. Here, we demonstrate that PDE1A, a Ca 2+ -calmodulin–stimulated PDE preferentially hydrolyzing cGMP, is predominantly cytoplasmic in medial “contractile” VSMCs but is nuclear in neointimal “synthetic” VSMCs. Using primary VSMCs, we show that cytoplasmic and nuclear PDE1A were associated with a contractile marker (SM-calponin) and a growth marker (Ki-67), respectively. This suggests that cytoplasmic PDE1A is associated with the “contractile” phenotype, whereas nuclear PDE1A is with the “synthetic” phenotype. To determine the role of nuclear PDE1A, we examined the effects loss-of-PDE1A function on subcultured VSMC growth and survival using PDE1A RNA interference and pharmacological inhibition. Reducing PDE1A function significantly attenuated VSMC growth by decreasing proliferation via G 1 arrest and inducing apoptosis. Inhibiting PDE1A also led to intracellular cGMP elevation, p27 Kip1 upregulation, cyclin D1 downregulation, and p53 activation. We further demonstrated that in subcultured VSMCs redifferentiated by growth on collagen gels, cytoplasmic PDE1A regulates myosin light chain phosphorylation with little effect on apoptosis, whereas inhibiting nuclear PDE1A has the opposite effects. These suggest that nuclear PDE1A is important in VSMC growth and survival and may contribute to the neointima formation in atherosclerosis and restenosis.

Aging per se is associated with reduced insulin secretion, which is an important contributing factor for pandemic of diabetes worldwide. Although underlying mechanism for it is not fully elucidated, a combination of reduced beta cell mass and impairment of insulin granule handing in the cell is most likely which may be due to age-related mitochondrial dysfunction and/or dysregulation of transcriptional factors. For effective prevention of diabetes in the elderly population, restoration of beta cell function is desired. Meanwhile, identification of insulin-deficient elderly patients with diabetes and an earlier institution of insulin therapy for them are recommended for improvement of treatment outcome.

The goal of this study was to know the fate of albuminuria in Japanese patients with type 2 diabetes under tight blood pressure and glycemic control.Patients having normoalbuminuria (urinary albumin excretion30 mg/g creatinine, n = 179) or microalbuminuria (albumin excretion 30-299 mg/g creatinine, n = 94) at baseline have been followed up for 8 years: ratio of men to women was 160/113, the mean age was 58 years, pretreatment HbA(1c) (A1C) was 8.8%, and blood pressure was 136/76 mmHg. A1C6.5% and blood pressure130/80 mmHg were targeted, and the A1C of 6.5 +/- 0.7% (mean +/- SD) and blood pressure of 127 +/- 11/72 +/- 6 mmHg have been maintained during the 8 years. Development of microalbuminuria or macroalbuminuria (albumin excretionor =300 mg/g creatinine) in initially normoalbuminuric patients and progression to macroalbuminuria or regression to normoalbuminuria in initially microalbuminuric patients were assessed at year 8.Development occurred in 27 (15%) of the normoalbuminuric patients and progression and regression in 16 (17%) and 20 (21%), respectively, of the microalbuminuric patients. Significant independent relationships existed between development and higher achieved mean systolic blood pressure (SBP) and regression and lower achieved mean SBP. In the patients with achieved mean SBP120 mmHg, development was 3%, progression was 11%, and regression was 44% during 8 years. Prediction for nephropathy by blood pressure and glycemia alone was limited. Nevertheless, albumin excretion at year 8 was positively correlated with achieved mean SBP and baseline albuminuria.Development and progression were low and regression was high with SBP of 120 mmHg, provided A1C was maintained at 6.5%.

The monomeric small GTPase Rab27a is specifically localized on both secretory granules and lysosome-related organelles. Although natural mutations of the Rab27a gene in human Griscelli syndrome and in ashen mice cause partial albinism and immunodeficiency reflecting the dysfunction of lysosome-related organelles, phenotypes resulting from the defective exocytosis of secretory granules have not been reported. To explore the roles of Rab27a in secretory granules, we analyzed insulin secretion profiles in ashen mice. Ashen mice showed glucose intolerance after a glucose load without signs of insulin resistance in peripheral tissues or insulin deficiency in the pancreas. Insulin secretion from isolated islets was decreased specifically in response to high glucose concentrations but not other nonphysiological secretagogues such as high K+ concentrations, forskolin, or phorbol ester. Neither the intracellular Ca2+ concentration nor the dynamics of fusion pore opening after glucose stimulation were altered. There were, however, marked reductions in the exocytosis from insulin granules predocked on the plasma membrane and in the replenishment of docked granules during glucose stimulation. These results provide the first genetic evidence to our knowledge for the role of Rab27a in the exocytosis of secretory granules and suggest that the Rab27a/effector system mediates glucose-specific signals for the exocytosis of insulin granules in pancreatic beta cells.

1. A dietary intervention study targeting female students by using cake containing soybean protein and isoflavone was conducted. Female students (n = 120) were divided into three Groups (A, 6.26 g of soybean protein and isoflavone at 50 mg/day; B, 1.36 g soybean protein and isoflavone 50 mg; and C, a wheat puff as placebo). Intervention period was 4 weeks. The ratio of hypercholesterol in each group indicated a high value; A: 25%, B: 17.9% and C: 24.4%. 2. Total cholesterol as well as the rate of hypercholesterolemia decreased in Group A. The average total cholesterol significantly reduced (P < 0.001) from 242 +/- 17 to 220 +/- 25 mg/dL in Group A. 3. Dietary intake of soy protein for 4 weeks could be effective in reducing CHD risk among Japanese female students with a high plasma cholesterol level.

Increased serum interleukin-6 (IL-6) concentrations have recently been reported in patients with subacute thyroiditis, possibly because of cytokine release from damaged thyroid cells. To investigate the changes in serum IL-6 concentrations in subacute thyroiditis during treatment with corticosteroid, serum IL-6 concentrations were determined by an enzyme-linked immunosorbent assay method in five patients with subacute thyroiditis. Serum IL-6 concentrations were increased moderately, and simultaneously, serum levels of T4, thyroglobulin, and C-reactive protein and erythrocyte sedimentation rate were increased markedly. The treatment with prednisolone rapidly and progressively decreased serum levels of thyroglobulin, T4, and C-reactive protein and the erythrocyte sedimentation rate. In contrast, serum IL-6 concentrations increased markedly 7 days after the treatment with prednisolone in all five patients and two of five patients showed further increases in serum IL-6 concentration on the 17th day. The rise in serum IL-6 levels in untreated patients with subacute thyroiditis in this study is compatible with previous reports. The rise in serum IL-6 levels after treatment with corticosteroid in subacute thyroiditis may reflect the dissociation between the persistent release of IL-6 from the damaged thyroid cells, immediate inhibition of secondary inflammatory reactions by corticosteroid, and the release of thyroglobulin and T4 from performed colloid stores in follicular lumen destroyed by subacute thyroiditis.

Angiotensin II (Ang II) and nitric oxide (NO)/natriuretic peptide (NP) signaling pathways mutually regulate each other. Imbalance of Ang II and NO/NP has been implicated in the pathophysiology of many vascular diseases. cGMP functions as a key mediator in the interaction between Ang II and NO/NP. Cyclic nucleotide phosphodiesterase 5A (PDE5A) is important in modulating cGMP signaling by hydrolyzing cGMP in vascular smooth muscle cells (VSMC). Therefore, we examined whether Ang II negatively modulates intracellular cGMP signaling in VSMC by regulating PDE5A. Ang II rapidly and transiently increased PDE5A mRNA levels in rat aortic VSMC. Upregulation of PDE5A mRNA was associated with a time-dependent increase of both PDE5 protein expression and activity. Increased PDE5A mRNA level was transcription-dependent and mediated by the Ang II type 1 receptor. Ang II-mediated activation of extracellular signal-regulated kinases 1/2 (ERK1/2) was essential for Ang II-induced PDE5A upregulation. Pretreatment of VSMC with Ang II inhibited C-type NP (CNP) stimulated cGMP signaling, such as cGMP dependent protein kinase (PKG)-mediated phosphorylation of vasodilator-stimulated-phosphoprotein (VASP). Ang II-mediated inhibition of PKG was blocked when PDE5 activity was decreased by selective PDE5 inhibitors, suggesting that upregulation of PDE5A expression is an important mechanism for Ang II to attenuate cGMP signaling. PDE5A may also play a critical role in the growth promoting effects of Ang II because inhibition of PDE5A activity significantly decreased Ang II-stimulated VSMC growth. These observations establish a new mechanism by which Ang II antagonizes cGMP signaling and stimulates VSMC growth.

Long-term administration of angiotensin II causes myocardial loss and cardiac fibrosis. We previously found iron deposition in the heart of the angiotensin II-infused rat, which may promote angiotensin II-induced cardiac damage. In the present study, we have investigated whether an iron chelator (deferoxamine) and a free radical scavenger (T-0970) affect the angiotensin II-induced upregulation of transforming growth factor-β1 (TGF-β1). Angiotensin II infusion for 7 days caused a robust increase in TGF-β1 mRNA expression in vascular smooth muscle cells, myofibroblast-like cells, and migrated monocytes/macrophages. T-0970 and deferoxamine suppressed the upregulation of TGF-β1 mRNA and reduced the extent of cardiac fibrosis in the heart of rats treated with angiotensin II. These agents blocked the angiotensin II-induced upregulation of heme oxygenase-1, a potent oxidative and cellular stress-responsive gene, but they did not significantly affect systolic blood pressure or plasma levels of aldosterone. In addition, T-0970 and deferoxamine suppressed the angiotensin II-induced upregulation of monocyte chemoattractant protein-1 in the heart. These results collectively suggest that iron and the iron-mediated generation of reactive oxygen species may contribute to angiotensin II-induced upregulation of profibrotic and proinflammatory genes, such as TGF-β1 and monocyte chemoattractant protein-1.

We have previously shown that abnormal iron metabolism might be one underlying mechanism of the renal damage observed in the angiotensin II-infused rat. Transforming growth factor-beta1 (TGF-beta1) is known to play a crucial role in the development of renal damage induced by activation of the renin-angiotensin-aldosterone system. The purpose of the present study was to examine the effects of an iron chelator and a free radical scavenger on the angiotensin II-induced upregulation of TGF-beta1 in the kidney. Rats were given angiotensin II (0.7 mg/kg/day) via osmotic minipumps for 7 days. The expressions of the mRNAs of TGF-beta1 and collagen types I and IV were significantly increased in response to angiotensin II treatment. Histologic analysis showed that TGF-beta1 expression was upregulated mainly in tubular epithelial cells, and occasionally in glomerular and perivascular cells, some of which were identified as monocytes and/or macrophages. Although tubular cells that overexpressed TGF-beta1 did not contain iron particles, angiotensin II-induced TGF-beta1 upregulation was suppressed by the iron chelator and the free radical scavenger. The free radical scavenger also suppressed angiotensin II-induced upregulation of heme oxygenase-1, an oxidative-stress sensitive gene. By contrast, administration of iron dextran to rats induced upregulation of TGF-beta1 mRNA. Collectively, these data suggest that the renal iron overload and presumed subsequent increase in oxidative stress play a role in angiotensin II-induced upregulation of the mRNAs of TGF-beta1 and collagen types I and IV in the kidney.

Axl, a receptor tyrosine kinase, is involved in cell survival, proliferation, and migration. We have shown that Axl expression increases in the neointima of balloon-injured rat carotids. Because oxidative stress is known to play a major role in remodeling of injured vessels, we hypothesized that H(2)O(2) might activate Axl by promoting autophosphorylation. H(2)O(2) rapidly stimulated Axl tyrosine phosphorylation in rat vascular smooth muscle cells within 1 min that was maximal at 5 min (6-fold). The response to H(2)O(2) was concentration-dependent with EC(50) of approximately 500 microm. Axl phosphorylation was partly dependent on production of its endogenous ligand, growth arrest gene 6 (Gas6), because Axl-Fc, a fragment of Axl extracellular domain that neutralizes Gas6, inhibited H(2)O(2)-induced Axl phosphorylation by 50%. Axl phosphorylation by H(2)O(2) was also attenuated by warfarin, which inhibits Gas6 activity by preventing post-translational modification. In intact vessels Axl was phosphorylated by H(2)O(2), and Axl phosphorylation was inhibited by warfarin treatment in balloon-injured carotids. Akt, a downstream target of Axl, was phosphorylated by H(2)O(2)in Axl(+/+) mouse aorta but significantly inhibited in Axl(-/-) aorta. Intimal proliferation was decreased significantly in a cuff injury model in Axl(-/-) mice compared with Axl(+/+) mice. In summary, Axl is an important signaling mediator for oxidative stress in cultured vascular smooth muscle cells and intact vessels and may represent an important therapeutic target for vascular remodeling and response to injury.

Protein acylation in glucose stimulation of insulin secretion in the beta-cells has been implicated. Accordingly, we attempted to identify the target(s) of acylation in the pancreatic islets. Rat pancreatic islets were labeled with [3H]palmitic acid for 1 h at 37 C, and the whole cell lysate was analyzed by SDS-PAGE and two-dimensional gel electrophoresis. The labeling of the proteins by [3H]palmitic acid was shown to be palmitoylation by chemical analyses. Palmitoylation of four distinct bands was recognized, and the palmitoylation was significantly reduced in all of them when the labeling was performed with high glucose. Quite interestingly, the degree of attenuation was particularly dominant for a 24-kDa doublet. Palmitoylation of the 24-kDa doublet was preferentially attenuated also by the mitochondrial fuels and an acylation inhibitor, cerulenin. The half-life of the labeling of the doublet was apparently shorter (approximately 45 min) than that of other bands on pulse chasing of the islets, irrespective of the presence or absence of high glucose. High glucose attenuation of the palmitoylation of the 24-kDa doublet was partially blocked by 20 mm mannoheptulose, a glucokinase inhibitor. Two-dimensional gel electrophoresis revealed that the doublet was composed of acidic peptides, and, by immunoprecipitation, it was shown not to be synaptosome-associated protein of 25 kDa. We identified rapidly turning over palmitoylated 24-kDa acidic proteins distinct from synaptosome-associated protein of 25 kDa in the pancreatic islets, which are preferentially modulated by fuel secretagogues. The data suggested a functional role of the palmitoylated 24-kDa doublet in nutrient stimulation of insulin secretion.

Atherosclerosis involves cellular immune responses and altered vascular smooth muscle cell (VSMC) function. Nitric oxide (NO)/cGMP is uniquely capable of inhibiting key processes in atherosclerosis. In this study, we determined the effects of NO/cGMP and their molecular mechanisms in the regulation of NF-κB–dependent gene expression in VSMCs. We found that cGMP-elevating agents such as the NO donor S -nitroso- N -acetylpenicillamine (SNAP) and C-type natriuretic peptide (CNP), reduced TNF-α–induced NF-κB–dependent reporter gene expression in rat aortic VSMCs in a cGMP-dependent manner. The effects of SNAP and CNP on NF-κB are mediated by cAMP-dependent protein kinase (PKA) but not cGMP-dependent protein kinase (PKG) based on the findings that the selective PKA inhibitor, PKI, abolished the effects of SNAP and CNP on NF-κB, whereas the PKG inhibitor Rp-8-Br-PET-cGMP had no effect. Inhibition of cGMP-inhibited cAMP-hydrolyzing phosphodiesterase 3 (PDE3) blocked SNAP- and CNP-elicited effects on NF-κB–dependent transcription. Furthermore, cGMP analogues such as 8-pCPT-cGMP, which selectively activates PKG but does not inhibit PDE3, had no effect on NF-κB–mediated transcription. Activation of PKA by SNAP or cAMP-elevating agents not only inhibited TNF-α–induced NF-κB–dependent reporter gene expression but also reduced endogenous NF-κB–dependent adhesion molecule and chemokine expression. These results suggest that SNAP and CNP exert inhibitory effects on NF-κB–dependent transcription by activation of PKA via cGMP-dependent inhibition of PDE3 activity. Therefore, PDE3 is a novel mediator of inflammation in VSMCs.

Two juvenile patients with multiple endocrine neoplasia type 1 (MEN1) who developed pituitary adenomas are reported. The first case, a 14-year-old girl, developed prolactinoma and manifested delayed puberty and growth arrest. The second case, a 16-year-old boy, was asymptomatic and a pituitary adenoma accompanied by mild elevation of PRL and GH was identified through family screening. His growth and pubertal development was not impaired. Medication with bromocriptine was started for both cases with good therapeutic responses. These cases emphasize relevance of early screening of endocrine disorders for members of families with MEN1.

Angiotensin II (Ang II) and nitric oxide (NO) signaling pathways mutually regulate each other by multiple mechanisms. Ang II regulates the expression of NO synthase and NO production, whereas NO downregulates the Ang II type I (AT1) receptor. In addition, downstream effectors of Ang II and NO signaling pathways also interact with each other. A feedback mechanism between Ang II and NO is critical for normal vascular structure and function. Imbalance of Ang II and NO has been implicated in the pathophysiology of many vascular diseases. In this review, we focus on the diverse ways in which Ang II and NO interact and the importance of the balance between the signaling pathways activated by these mediators.

A 67-year-old man with thrombocytopenia, and amegakaryocytic but otherwise normal bone marrow, was evaluated. Antibody against thrombocytes was negative and the half-life of thrombocytes was normal. In vitro clonal culture of the patient's bone marrow cells yielded no megakaryocyte colony with normal granulocyte-macrophage and erythroid colony formation. Megakaryocyte colony formation of the control bone marrow cells was significantly suppressed by the addition of the patient's serum to the culture, suggesting the existence of humoral inhibitory factor(s) for megakaryocyte colony formation. Therapeutic trials with plasma exchange, cyclosporine, prednisolone, and cyclosporine plus prednisolone were all unsuccessful, but serious bleeding has been absent.(Internal Medicine 33:147-149, 1994)

Isolated rat islets were exposed to cAMP-elevating agents and/or nutrients. Insulin exocytosis subsequently triggered by a depolarizing concentration of K(+) or a stimulatory concentration of glucose was employed as an index of time-dependent potentiation (TDP). Stimulatory concentrations (or=5.5 mM) of glucose caused TDP, and 6 micro M forskolin (an activator of adenylyl cyclase) significantly enhanced it (3.1-fold at most). Forskolin produced an 8.0-fold increase in islet cell cAMP; however, it returned to the baseline after washout by the time of stimulation of exocytosis. Two millimoles of dibutyryl cAMP (a cAMP analog), 0.1 mM isobutylmethylxanthine (a phosphodiesterase inhibitor), and 100 nM glucagon-like peptide-1 (an incretin hormone) also enhanced glucoseinduced TDP. The time-dependent effect of cAMP was not attenuated by protein kinase A inhibitors (200 micro M adenosine 3',5'-cyclic monophosphothioate, Rp isomer, and 10 micro M H89). Although glucose-induced TDP was attenuated by NaN(3) (a mitochondrial poison) and cerulenin (an inhibitor of protein acylation), cAMP enhancement of it was unaffected by these agents. In conclusion, cAMP time-dependently stimulates insulin exocytosis, provided the extracellular glucose concentration is equivalent to or higher than ambient plasma levels. Protein kinase A, mitochondrial metabolism, and protein acylation are not involved in this cAMP action. Incretin stimulation of insulin exocytosis may occur in part via this mechanism.

We report two cases of type 1 diabetes mellitus fulminantly developed as diabetic ketoacidosis (DKA) at 19 weeks of gestation and immediately after delivery. Development of type 1 diabetes around pregnancy is not rare, but its fulminant development is highly uncommon. We also review the relevant literature concerning mostly Japanese cases. In our cases, the group of patients with fulminant progressive diabetes mellitus associated with pregnancy required insulin replacement therapy even after the acute period and showed high value of pancreatic exocrine enzymes, i.e. amylase, elastase, and lipase. The phenotype of this group was similar to "nonautoimmune, fulminant type 1 diabetes" described by Imagawa et al., where the laboratory data of type 1 diabetes-related autoantibodies showed negative. It is well known that autoimmune diseases are in good control during pregnancy. Our present finding suggests that this type of fulminant type 1 diabetes mellitus associated with pregnancy might develop as a consequence of a nonautoimmune mechanism.

The klotho gene, originally identified by insertional mutagenesis in mice, suppresses the expression of multiple aging-associated phenotypes. This gene is predominantly expressed in the kidney. Recent studies have shown that expression of renal klotho gene is regulated in animal models of metabolic diseases and in humans with chronic renal failure. However, little is known about the mechanisms and the physiological relevance of the regulation of the expression of the klotho gene in the kidney in some diseased conditions. In the present study, we first investigated the role of angiotensin II in the regulation of renal klotho gene expression. Long-term infusion of angiotensin II downregulated renal klotho gene expression at both the mRNA and protein levels. This angiotensin II-induced renal klotho downregulation was an angiotensin type 1 receptor-dependent but pressor-independent event. Adenovirus harboring mouse klotho gene (ad-klotho, 3.3×10 10 plaque forming units) was also intravenously administered immediately before starting angiotensin II infusion in some rats. This resulted in a robust induction of Klotho protein in the liver at day 4, which was still detectable 14 days after the gene transfer. Ad-klotho gene transfer, but not ad-lacZ gene transfer, caused an improvement of creatinine clearance, decrease in urinary protein excretion, and amelioration of histologically demonstrated tubulointerstitial damage induced by angiotensin II administration. Our data suggest that downregulation of the renal klotho gene may have an aggravative role in the development of renal damage induced by angiotensin II, and that induction of the klotho gene may have therapeutic possibilities in treating angiotensin II-induced end organ damage.

Inhibition of insulin release by norepinephrine has been attributed to activation of ATP-sensitive K+ channels, inactivation of voltage-dependent Ca2+ channels, and inhibition of adenylyl cyclase. However, direct inhibitory action of norepinephrine at a distal site of stimulus-secretion coupling has also been suggested. To obtain more direct evidence for norepinephrine inhibition of insulin release at a distal site, we performed experiments in intact, non-permeabilized beta cells. In rat pancreatic islets, a combination of glucose, phorbol ester and forskolin under stringent Ca2+-free conditions was used as a trigger of insulin exocytosis at a distal site. Norepinephrine inhibited this Ca2+-independent insulin release in a concentration-dependent manner, with an IC50 of 50 nM. The inhibition was complete, reversible, and pertussis toxin-sensitive, and not associated with any reduction of cAMP content in the islet cells. In conclusion, norepinephrine strongly, yet reversibly, inhibits insulin release in intact beta cells at a late step of exocytosis, through pertussis toxin-sensitive, G protein-mediated mechanism(s).

Nutrient augmentation of Ca(2+)-triggered insulin release occurs in an ATP-sensitive K(+) (K(ATP)) channel--independent manner. Here, using rat islets, we explored the possibility of the K(ATP) channel-independent nutrient triggering of insulin release. In the presence of 250 micromol/l diazoxide, simultaneous application of forskolin and 16.7 mmol/l glucose strongly stimulated insulin release: fourfold and eightfold increases with 1 and 30 micromol/l forskolin, respectively. alpha-Ketoisocaproate (KIC) and 3-isobutylmethylxanthine (IBMX) could be used in place of glucose and forskolin, respectively, to trigger insulin release in the presence of diazoxide. Triggering of insulin release by a combination of nutrients and forskolin was not attenuated by 10 micromol/l nifedipine (a blocker of voltage-dependent Ca(2+) channels) and 2 micromol/l thapsigargin (an inhibitor of intracellular Ca(2+)-ATPase), ascertaining independence of this phenomenon from Ca(2+) entry and from intracellular Ca(2+) liberation. As anticipated, the action of glucose and KIC was greatly (80%) suppressed by inhibition of mitochondrial metabolism by 2 mmol/l sodium azide (NaN(3)). A combination of palmitate and dimethyl glutamate (a cell-permeable glutamate donor), but not either one alone, weakly but unequivocally triggered insulin release when applied simultaneously with forskolin. In this case, however, mitochondrial poisoning by azide was without effect. The finding suggests that a combination of induced palmitoylation and cytosolic glutamate accumulation partially reconstituted signaling beyond mitochondrial metabolism in the beta-cell upon glucose stimulation. In conclusion, a combination of cAMP signal and nutrients potently triggers insulin release under full activation of the K(ATP) channel, indicating the multiplicity of driving force for insulin exocytosis.