High Glucose Stimulates Mineralocorticoid Receptor Transcriptional Activity Through the Protein Kinase C ß Signaling.

Activation of mineralocorticoid receptor (MR) is shown in resistant hypertension including diabetes mellitus. Although protein kinase C (PKC) signaling is involved in the pathogenesis of diabetic complications, an association between PKC and MR is not known. Activation of PKCα and PKCß by TPA (12-O-Tetradecanoylphorbol 13-acetate) increased MR proteins and its transcriptional activities in HEK293-MR cells. In contrast, a high glucose condition resulted in PKCß but not PKCα activation, which is associated with elevation of MR protein levels and MR transcriptional activities. Reduction of endogenous PKCß by siRNA decreased those levels. Interestingly, high glucose did not affect MR mRNA levels, but rather decreased ubiquitination of MR proteins. In db/db mice kidneys, levels of phosphorylated PKCß2, MR and Sgk-1 proteins were elevated, and the administration of PKC inhibitor reversed these changes compared to db/+ mice. These data suggest that high glucose stimulates PKCß signaling, which leads to MR stabilization and its transcriptional activities.

Aldosterone-producing adrenocortical carcinoma with prominent hepatic metastasis diagnosed by liver biopsy: a case report.

BACKGROUND: Aldosterone-producing adrenocortical carcinoma is a rare malignancy, which is usually diagnosed by histopathological examination of the excised tumor. In inoperable cases, aldosterone-producing ACC diagnosed by immunohistochemical staining of the metastatic tumor for Cytochrome P450 (CYP) 11ß has not previously been reported and even in that case staining for adrenocortical-specific adrenal 4 binding protein/steroidogenic factor1 (Ad4BP/SF1) and steroidogenic enzymes has not been reported. CASE PRESENTATION: We report the case of a 67-year-old Japanese woman with aldosterone-producing adrenocortical carcinoma. Laboratory findings showed severe hypopotassemia. Endocrinological examination revealed an increased plasma aldosterone concentration and suppressed plasma renin activity. Plasma dehydroepiandrosterone sulfate (DHEA-S) was elevated. Diurnal variation in serum cortisol was lost and administration of 1 mg and 8 mg dexamethasone did not suppress serum cortisol levels. From the 24-h urine collection sample, urine aldosterone and urine cortisol levels were greatly increased. Therefore, autonomous excess production was observed for the three adrenal cortex hormones. Abdominal computed tomography and magnetic resonance imaging showed a right adrenal tumor and a huge liver tumor. Adrenocortical carcinoma with metastatic liver cancer was strongly suggested, however surgery could not be considered due to stage IV disease: the liver tumor was too large and cardiac ultrasonography indicated that her cardiac function was poor. Therefore, a liver biopsy was taken to properly determine the diagnosis. Immunohistochemical stains for Ad4BP/SF1 and steroidogenic enzymes were positive. Ad4BP/SF-1 was originally identified as a steroidogenic, tissue-specific transcription factor implicated in the expression of the steroidogenic CYP gene encoding cytochrome P450s. Hence we could diagnose the patient as having adrenocortical carcinoma with metastatic liver cancer. CONCLUSION: This rare case had severe hypopotassemia accompanied with not only increased cortisol and DHEA-S but also aldosterone. We reached the diagnosis of adrenocortical carcinoma with metastatic liver cancer based on positive immunohistochemical staining of Ad4BP/SF1 in the liver biopsy specimen. We have reported the first case of aldosterone-producing adrenocortical carcinoma diagnosed solely by immunohistochemical staining for adrenocortical-specific Ad4BP/SF1 and steroidogenic enzymes in a metastatic liver tumor.

A missense single-nucleotide polymorphism in the sialic acid acetylesterase (SIAE) gene is associated with anti-PIT-1 antibody syndrome.

A novel clinical entity related to autoimmune polygladular syndrome (APS) termed "anti-PIT-1 antibody syndrome" is characterized by a presence of circulating autoantibody against the pituitary-specific transcriptional factor-1 (PIT-1) with acquired specific defect in GH, PRL, and TSH. Although autoimmunity to PIT-1 has been suggested, the underlying mechanisms remain to be elucidated. Sialic acid acetylesterase (SIAE) plays a crucial role in regulating the threshold of autoantibody production of B-cells and the defective variants of SIAE are associated with an increased risk of various autoimmune diseases such as type 1 diabetes (T1DM). To explore the link between anti-PIT-1 antibody syndrome and SIAE, we analyzed SIAE gene in 3 patients with anti-PIT-1 antibody syndrome and 200 healthy control subjects, and compared the prevalence of single nucleotide polymorphisms. Intriguingly, we found A467V SIAE variants (c.1400C>T, rs7941523) in a heterozygous state in all the patients with anti-PIT-1 antibody syndrome, while we detected in 6 % of control subjects, in which the prevalence was significantly increased in the patients (P<0.0005). Considering the physiological function of SIAE and the clinical features of anti-PIT-1 antibody syndrome, present data imply a novel aspect of the pathogenesis in this disease.

Deletion of the NESP55 differentially methylated region causes loss of maternal GNAS imprints and pseudohypoparathyroidism type Ib.

Epigenetic defects in the imprinted GNAS cluster are associated with pseudohypoparathyroidism type Ib. In two kindreds with this disorder, we now report deletions that remove the differentially methylated region encompassing exon NESP55 and exons 3 and 4 of the antisense transcript. When inherited from a female, either deletion abolishes all maternal GNAS imprints and derepresses maternally silenced transcripts, suggesting that the deleted region contains a cis-acting element that controls imprinting of the maternal GNAS allele.

Effects of co-administration of candesartan with pioglitazone on inflammatory parameters in hypertensive patients with type 2 diabetes mellitus: a preliminary report.

BACKGROUND: Angiotensin receptor blockers (ARBs) are reported to provide direct protection to many organs by controlling inflammation and decreasing oxidant stress. Pioglitazone, an anti-diabetic agent that improves insulin resistance, was also reported to decrease inflammation and protect against atherosclerosis. This study aimed to evaluate the utility of combination therapy with both medicines from the viewpoint of anti-inflammatory effects. METHODS: We administered candesartan (12 mg daily) and pioglitazone (15 mg daily) simultaneously for 6 months to hypertensive patients with type 2 diabetes mellitus (T2DM) and evaluated whether there were improvements in the serum inflammatory parameters of high-molecular-weight adiponectin (HMW-ADN), plasminogen activator inhibitor-1 (PAI-1), highly sensitive C-reactive protein (Hs-CRP), vascular cell adhesion molecule-1 (VCAM-1), and urinary-8-hydroxydeoxyguanosine (U-8-OHdG). We then analyzed the relationship between the degree of reductions in blood pressure and HbA1c values and improvements in inflammatory factors. Furthermore, we analyzed the relationship between pulse pressure and the degree of lowering of HbA1c and improvements in inflammatory factors. Finally, we examined predictive factors in patients who received benefits from the co-administration of candesartan with pioglitazone from the viewpoint of inflammatory factors. RESULTS: After 6 months of treatment, in all patients significant improvements from baseline values were observed in HMW-ADN and PAI-1 but not in VCAM-1, Hs-CRP, and U-8-OHdG. Changes in HbA1c were significantly correlated with changes in HMW-ADN and PAI-1 in all patients, but changes in blood pressure were not correlated with any of the parameters examined. Correlation and multilinear regression analyses were performed to determine which factors could best predict changes in HbA1c. Interestingly, we found a significant positive correlation of pulse pressure values at baseline with changes in HbA1c. CONCLUSIONS: Our data suggest that the pulse pressure value at baseline is a key predictive factor of changes in HbA1c. Co-administration of candesartan with pioglitazone, which have anti-inflammatory (changes in HMW-ADN and PAI-1) effects and protective effects on organs, could be an effective therapeutic strategy for treating hypertensive patients with type 2 diabetes mellitus. TRIAL REGISTRATION: UMIN-CTR: UMIN000010142.

Effects of candesartan in hypertensive patients with type 2 diabetes mellitus on inflammatory parameters and their relationship to pulse pressure.

BACKGROUND: Angiotensin receptor blockers (ARBs) are reported to provide direct protection to many organs by controlling inflammation and decreasing oxidant stress in patients without arteriosclerosis. This study aimed to evaluate (1) whether an ARB (candesartan) decreases values for inflammatory parameters in hypertensive patients with type 2 diabetes mellitus of long duration accompanied by arteriosclerosis and (2) whether there any predictors of which patients would receive the benefits of organ protection by candesartan. METHODS: We administered candesartan therapy (12 mg daily) for 6 months and evaluated whether there was improvement in serum inflammatory parameters high molecular weight adiponectin (HMW-ADN), plasminogen activator inhibitor-1 (PAI-1), highly sensitive C-reactive protein (Hs-CRP), vascular cell adhesion molecule-1 (VCAM-1) in serum and urinary-8-hydroxydeoxyguanosine (U-8-OHdG). We then analyzed the relationship between the degree of lowering of blood pressure and inflammatory factors and the relationship between pulse pressure and inflammatory factors. Finally, we analyzed predictive factors in patients who received the protective benefit of candesartan. RESULTS: After 6 months of treatment, significant improvements from baseline values were observed in all patients in HMW-ADN and PAI-1 but not in Hs-CRP, VCAM-1 and U-8-OHdG. Multilinear regression analysis was performed to determine which factors could best predict changes in HMW-ADN and PAI-1. Changes in blood pressure were not significant predictors of changes in metabolic factors in all patients. We found that the group with baseline pulse pressure <60 mmHg had improved HMW-ADN and PAI-1 values compared with the group with baseline pulse pressure ≥ 60 mmHg. These results suggest that pulse pressure at baseline could be predictive of changes in HMW-ADN and PAI-1. CONCLUSIONS: Candesartan improved inflammatory parameters (HMW-ADN and PAI-1) in hypertensive patients with type 2 diabetes mellitus of long duration independent of blood pressure changes. Patients with pulse pressure <60 mmHg might receive protective benefits by candesartan. TRIAL REGISTRATION: UMIN000007921.

Efonidipine, a Ca(2+)-channel blocker, enhances the production of dehydroepiandrosterone sulfate in NCI-H295R human adrenocortical carcinoma cells.

Steroid biosynthesis is initiated with transportation of cholesterol along with steroidogenic acute regulatory protein (StAR) into the mitchondria and is achieved with several steroidogenic enzymes. It has been reported that Ca(2+) channel blockers (CCBs), such as azelnidipine, efonidipine and nifedipine, suppress the biosynthesis of aldosterone and cortisol, but the overall effects of CCBs on steroid biosynthesis remain to be clarified. The present study was designed to evaluate the effects of CCBs on the expression of steroidogenic enzymes and the production of adrenal androgen, dehydroepiandrosterone sulfate (DHEA-S) that has anti-atherosclerotic actions. NCI-H295R human adrenocortical carcinoma cells and HepG2 human hepatoma cells were cultured for 24 hours with or without a CCB (amlodipine, efonidipine, nifedipine, azelnidipine R(-)-efonidipine, verapamil or diltiazem). HepG2 hepatoma cells were used to confirm the effects of CCBs on the expression of StAR. In fact, efonidipine and nifedipine increased the expression of StAR in HepG2 cells. Efonidipine and nifedipine, but not other examined CCBs, also increased the N(6), 2'-O-dibutyryladenosine 3',5'-cyclic monophosphate (dbcAMP)-induced StAR mRNA, which reflects the action of adrenocorticotropic hormone, and efonidipine and R(-)-efonidipine enhanced the dbcAMP-induced DHEA-S production in NCI-H295R adrenocortical carcinoma cells. Therefore, efonidipine and nifedipine might increase the expression of StAR and, in turn, efonidipine enhanced the dbcAMP-induced DHEA-S production, independent of Ca(2+) channel blockade. These results indicate that such effects are not associated with Ca(2+) influx. Moreover, only efonidipine enhanced the angiotensin II-induced expression of StAR mRNA (P < 0.01 vs. angiotensin II alone). In conclusion, efonidipine might exert an additional action beyond anti-hypertensive actions.

Role of transient receptor potential vanilloid 2 in LPS-induced cytokine production in macrophages.

There is considerable evidence indicating that intracellular Ca2+ participates as a second messenger in TLR4-dependent signaling. However, how intracellular free Ca2+ concentrations ([Ca2+]i) is increased in response to LPS and how they affect cytokine production are poorly understood. Here we examined the role of transient receptor potential (TRP), a major Ca2+ permeation pathway in non-excitable cells, in the LPS-induced cytokine production in macrophages. Pharmacologic experiments suggested that TRPV family members, but neither TRPC nor TRPM family members, are involved in the LPS-induced TNFalpha and IL-6 production in RAW264 macrophages. RT-PCR and immunoblot analyses showed that TRPV2 is the sole member of TRPV family expressed in macrophages. ShRNA against TRPV2 inhibited the LPS-induced TNFalpha and IL-6 production as well as IkappaBalpha degradation. Experiments using BAPTA/AM and EGTA, and Ca2+ imaging suggested that the LPS-induced increase in [Ca2+]i involves both the TRPV2-mediated intracellular and extracellular Ca2+ mobilizations. BAPTA/AM abolished LPS-induced TNFalpha and IL-6 production, while EGTA only partially suppressed LPS-induced IL-6 production, but not TNFalpha production. These data indicate that TRPV2 is involved in the LPS-induced Ca2+ mobilization from intracellular Ca2+ store and extracellular Ca2+. In addition to Ca2+ mobilization through the IP3-receptor, TRPV2-mediated intracellular Ca2+ mobilization is involved in NFkappaB-dependent TNFalpha and IL-6 expression, while extracellular Ca2+ entry is involved in NFkappaB-independent IL-6 production.

Possible involvement of corticotropin-releasing factor receptor signaling on vascular inflammation.

Based on the reported anti-inflammatory and anti-stress responses by corticotropin-releasing factor (CRF) receptor signaling, endogenous CRF receptor agonists, CRF, urocortin (UCN) I and its related peptides, may play protective roles against cardiovascular stresses via the CRF receptor signaling. Therefore, the present study was designed to evaluate the involvement of CRF receptor signaling against vascular inflammatory stress using human aortic endothelial cells (HAECs). In addition, due to the possible involvement of CRF receptor signaling in the effects of statin on endothelial cells, the effects of pitavastatin on the expression of UCN-related peptides in HAECs were also evaluated. HAECs expressed all UCNs, CRF type 1 receptor (CRF-R1), and CRF type 2 (CRF-R2)alpha and CRF-R2beta mRNAs. Real time PCR analysis revealed that UCN I mRNA was down-regulated, whereas UCN II mRNA was up-regulated by tumor necrosis factor (TNF)-alpha. Selective blockade of CRF-R1 resulted in significant increase in TNF-alpha-induced expression of vascular adhesion molecule-1 at mRNA level and E-selectin at mRNA and protein levels. Pitavastatin up-regulated UCN I mRNA without TNF-alpha, but co-incubation with pitavastatin and TNF-alpha resulted in decrease in UCN I mRNA. On the contrary, UCN II, CRF-R1, and CRF-R2 mRNAs were markedly increased by co-incubation of pitavastatin and TNF-alpha. These facts indicate that CRF-R1 signaling may have protective role against TNF-alpha-induced vascular inflammation. In addition, because of up-regulation of CRF-R1 mRNA by pitavastatin with or without TNF-alpha, CRF-R1 may be involved in the vasoprotective effects of pitavastatin.

Coexistence of aldosterone-producing adrenocortical adenoma and pheochromocytoma in an ipsilateral adrenal gland.

A 40-year-old female, diagnosed as essential hypertension, demonstrated a 2 cm mass in left adrenal gland by computed tomography without abnormal endocrinological findings. (131)I-adosterol and (123)I-metaiodobenzylguanidine (MIBG) scintigraphy at 39 years of age showed no abnormal accumulation. Follow up (131)I-adosterol scintigraphy performed one year later showed apparently abnormal uptake and slightly elevated uptake in left adrenal gland. Her physical examination was unremarkable except for mild hypertension. Routine blood chemistry was normal except for hypokalemia. Endocrinological date revealed suppressed plasma renin activity, and elevated plasma aldosterone concentration, and noradrenalin levels. Serial T2-weighted magnetic resonance imaging clearly demonstrated two distinct tumors. Furthermore, selective adrenal venous sampling with intravenous ACTH infusion indicated aldosterone-producing adrenocortical adenoma (APA) in left adrenal gland. During operation of adrenal tumor, blood pressure elevated markedly and complication of pheochromocytoma (PC) was suspected. Immunohistochemical findings after left adrenolectomy revealed that the adrenal mass was compatible with APA and PC. Risk of operation against undiagnosed PC is very high and, therefore, it must be diagnosed before surgery. Herein, we present an extremely rare case of the simultaneous occurrence of both APA and PC in an ipsilateral adrenal gland.

Prospective randomized study for optimal insulin therapy in type 2 diabetic patients with secondary failure.

BACKGROUND: The large clinical trials proved that Basal-Bolus (BB) insulin therapy was effective in the prevention of diabetic complications and their progression. However, BB therapy needs multiple insulin injections per a day. In this regard, a biphasic insulin analogue needs only twice-daily injections, and is able to correct postprandial hyperglycemia. Therefore it may achieve the blood glucose control as same as that of BB therapy and prevent the diabetic complications including macroangiopathy. METHODS: In PROBE (Prospective, Randomized, Open, Blinded-Endpoint) design, forty-two type 2 diabetic patients (male: 73.8%, median(inter quartile range) age: 64.5(56.8-71.0)years) with secondary failure of sulfonylurea (SU) were randomly assigned to BB therapy with a thrice-daily insulin aspart and once-daily basal insulin (BB group) or to conventional therapy with a twice-daily biphasic insulin analogue (30 Mix group), and were followed up for 6 months to compare changes in HbA1c, daily glycemic profile, intima-media thickness (IMT) of carotid artery, adiponectin levels, amounts of insulin used, and QOL between the two groups. RESULTS: After 6 months, HbA1c was significantly reduced in both groups compared to baseline (30 Mix; 9.3(8.1-11.3) --> 7.4(6.9-8.7)%, p < 0.01, vs BB;8.9(7.7-10.0) --> 6.9(6.2-7.3)%, p < 0.01), with no significant difference between the groups in percentage change in HbA1c (30 Mix; -14.7(-32.5- (-)7.5)% vs BB -17.8(-30.1- (-)11.1)%, p = 0.32). There was a significant decrease in daily glycemic profile at all points except dinner time in both groups compared to baseline. There was a significant increase in the amount of insulin used in the 30 Mix group after treatment compared to baseline (30 Mix;0.30(0.17-0.44) --> 0.39(0.31-0.42) IU/kg, p = 0.01). There was no significant difference in IMT, BMI, QOL or adiponectin levels in either group compared to baseline. CONCLUSION: Both BB and 30 mix group produced comparable reductions in HbA1c in type 2 diabetic patients with secondary failure. There was no significant change in IMT as an indicator of early atherosclerotic changes between the two groups. The basal-bolus insulin therapy may not be necessarily needed if the type 2 diabetic patients have become secondary failure. TRIAL REGISTRATION: Current Controlled Trials number, NCT00348231.

Cellular physiology of rat cardiac myocytes in cardiac fibrosis: in vitro simulation using the cardiac myocyte/cardiac non-myocyte co-culture system.

An understanding of the cellular physiology of cardiac myocytes (MCs) and non-myocytes (NMCs) may help to explain the mechanisms underlying cardiac hypertrophy. Despite numerous studies using MC/NMC co-culture systems, it is difficult to precisely evaluate the influence of each cell type because of the inherent cellular heterogeneity of such a system. Here we developed a co-culture system using Wistar rat neonatal MCs and NMCs isolated by discontinuous Percoll gradient and adhesion separation methods and cultured on either side of insert well membranes. Co-culture of MCs and NMCs resulted in significant increases in [3H]-leucine incorporation by MCs, in the amount of protein synthesized by MCs, and in the secretion of natriuretic peptides, while the addition of MCs to NMC cultures significantly reduced [3H]-thymidine incorporation by NMCs. Interestingly, the percentage of the brain natriuretic peptide (BNP) component of total natriuretic peptide secreted (atrial natriuretic peptide+BNP) increased as the number of NMCs placed in the MC/NMC co-culture system increased. However, MCs did not affect production of angiotensin II (Ang II) by NMCs or secretion of endothelin-1 and transforming growth factor-beta1 into the MC/NMC co-culture system. This finding was supported by the anti-hypertrophic and anti-fibrotic actions of RNH6270, an active form of olmesartan, on MCs in the MC/NMC co-culture system and on NMCs that may synthesize Ang II in the heart. The present data indicate that cardiac fibrosis may not only facilitate MC hypertrophy (possibly through the local angiotensin system) but may also change particular pathophysiological properties of MCs, such as the secretory pattern of natriuretic peptides.

Upregulation of heat shock transcription factor 1 plays a critical role in adaptive cardiac hypertrophy.

Exercise-induced cardiac hypertrophy has been reported to have better prognosis than pressure overload-induced cardiac hypertrophy. Cardiac hypertrophy induced by exercise was associated with less cardiac fibrosis and better systolic function, suggesting that the adaptive mechanisms may exist in exercise-induced hypertrophy. Here, we showed a critical role of heat shock transcription factor 1 (HSF1), an important transcription factor for heat shock proteins, in the adaptive mechanism of cardiac hypertrophy. We examined expression of 8800 genes in the heart of exercise-induced hypertrophy model using DNA chip technique and compared with pressure overload-induced hypertrophy. Expression of HSF1 and its target molecule heat shock proteins was significantly upregulated in the heart by exercise but not by chronic pressure overload. Constitutive activation of HSF1 in the heart significantly ameliorated death of cardiomyocytes and cardiac fibrosis and thereby prevented cardiac dysfunction as well as hypertrophy induced by chronic pressure overload. Conversely, decreased activity of HSF1 in the heart promoted cardiac dysfunction in response to exercise, a load that normally leads to adaptive hypertrophy with preserved systolic function. Likewise, cardiac function was significantly impaired from the early phase of pressure overload, when HSF1 activation was inhibited. These results suggest that HSF1 plays a critical role in the transition between adaptive and maladaptive hypertrophy.

Acute liver damage and subsequent hypophosphatemia in malnourished patients: case reports and review of literature.

OBJECTIVE: The relationship between liver damage and subsequent hypophosphatemia in malnourished patients will be discussed. METHOD: The authors report two malnourished females who developed severe liver damage and subsequent hypophosphatemia. Liver damage commenced suddenly after over a week of hospitalization and deteriorated rapidly. Although the precise pathology of the liver damage could not be determined and the specific cause was not identified, steatohepatitis associated with fatty liver might be considered. RESULTS: Hypophosphatemia following liver damage was considered to be the result of hepatocyte regeneration and replacement of phosphorus was an effective treatment. CONCLUSION: Hypophosphatemia in these cases suggested improvement from liver damage; however, it is commonly known that hypophosphatemia has a central role in refeeding syndrome in malnourished patients. Therefore, it was concluded that attention should be paid to hypophosphatemia after liver damage.

Immunohistochemical analysis of 11-beta-hydroxysteroid dehydrogenase type 2 and glucocorticoid receptor in subclinical Cushing's disease due to pituitary macroadenoma.

Subclinical Cushing's disease (SCD) is characterized by lack of clinically evident Cushingoid features, despite abnormal hypersecretion of ACTH. Nearly half the cases of SCD are due to macroadenomas, and in the majority of them, ACTH secretion is not inhibited even by high-dose dexamethasone. Impaired glucocorticoid (GC) action may be correlated with the proliferation and development of pituitary macroadenomas causing SCD. In this study, immunohistochemical analysis of the resected tumors were performed to evaluate the expression of 11beta-hydroxysteroid dehydrogenase type 2 (11betaHSD2) and glucocorticoid receptor (GR) in pituitary tissues obtained from two SCD (macroadenomas), eight Cushing's disease (CD) (microadenomas), nine acromegaly, and nine normal pituitary (NP). Scattered 11betaHSD2-immunopositive cells were detected in all NP tissues, but its immunoreactivity was totally absent in any tumorous tissues except two CD. Scattered GR-immunopositive cells were also detected and GR immunostaining was restricted to the cytosol in NP tissue. In contrast, GR-immunopositive cells were abundantly present and GR immunostaining was restricted to the nucleus in all the tumorous tissues. There were marked differences in both expression levels and localization between NP tissues and all the tumors. There may be a mechanism other than that via 11betaHSD2 for causes of impaired negative feedback action by GC in SCD and CD, but results of our present study suggest that impaired GC action may be involved, at least in part, in tumorigenesis of SCD and CD.

Primary Aldosteronism With Type 2 Diabetes Mellitus Requires More Antihypertensive Drugs for Blood Pressure Control: A Retrospective Observational Study.

BACKGROUND: Diabetes mellitus (DM) and primary aldosteronism (PA) have been reported to induce drug-resistant hypertension and atherosclerosis. It is likely that blood pressure (BP) control becomes far more difficult in PA patients with DM. However, precise clinical characteristics of PA with type 2 DM especially in the aspect of BP control are not clear. METHODS: The study included 18 patients who were diagnosed as PA with DM and 52 PA patients without DM who matched age and sex and chosen as a control group. We have compared differences in BP control, use of antihypertensive agents and clinical characteristics between PA patients with and without DM. RESULTS: There was no difference with regard to the duration of hypertension and BP control between either group. Interestingly, the PA with DM group was found to require more antihypertensive agents than the PA without DM group (number of antihypertensive agents used, 2.0 ± 1.5 vs. 1.3 ± 1.1; P < 0.05, respectively). In the 28 patients who underwent measurement of central BP (CBP) values, plasma aldosterone concentration (PAC) was high in the PA with DM group. Furthermore, a positive correlation was shown between PAC and CBP (r = 0.58; P < 0.01); the higher the PAC, the higher the CBP of patient. CONCLUSIONS: These results might suggest that hypertension becomes more difficult to control in PA patients with DM in the future.

Somatic and germ-line mutations of the HRPT2 gene in sporadic parathyroid carcinoma.

BACKGROUND: We looked for mutations of the HRPT2 gene, which encodes the parafibromin protein, in sporadic parathyroid carcinoma because germ-line inactivating HRPT2 mutations have been found in a type of familial hyperparathyroidism--hyperparathyroidism-jaw tumor (HPT-JT) syndrome--that carries an increased risk of parathyroid cancer. METHODS: We directly sequenced the full coding and flanking splice-junctional regions of the HRPT2 gene in 21 parathyroid carcinomas from 15 patients who had no known family history of primary hyperparathyroidism or the HPT-JT syndrome at presentation. We also sought to confirm the somatic nature of the identified mutations and tested the carcinomas for tumor-specific loss of heterozygosity at HRPT2. RESULTS: Parathyroid carcinomas from 10 of the 15 patients had HRPT2 mutations, all of which were predicted to inactivate the encoded parafibromin protein. Two distinct HRPT2 mutations were found in tumors from five patients, and biallelic inactivation as a result of a mutation and loss of heterozygosity was found in one tumor. At least one HRPT2 mutation was demonstrably somatic in carcinomas from six patients. Unexpectedly, HRPT2 mutations in the parathyroid carcinomas of three patients were identified as germ-line mutations. CONCLUSIONS: Sporadic parathyroid carcinomas frequently have HRPT2 mutations that are likely to be of pathogenetic importance. Certain patients with apparently sporadic parathyroid carcinoma carry germ-line mutations in HRPT2 and may have the HPT-JT syndrome or a phenotypic variant.

Coefficient of variation of R-R intervals in electrocardiogram is a sensitive marker of anemia induced by autonomic neuropathy in type 1 diabetes.

The present study investigated the relationship between hemoglobin (Hb) levels and autonomic failure using a sensitive marker, coefficient of variation of R-R intervals in electrocardiogram (CVR-R) in order to clarify a cause of normocytic normochromic anemia in type 1 diabetic patients without overt nephropathy. We recruited 46 patients with type 1 diabetes and measured creatinine clearance (Ccr), HbA1c, albuminuria, Hb levels and CVR-R of all patients. In addition, the status of diabetic retinopathy and neuropathy were also evaluated. Serum erythropoietin (EPO), Fe, total iron binding capacity, lactate dehydrogenase, total bilirubin levels and number of reticulocytes and mean corpuscular volume were also measured to distinguish types of anemia. To survey the statistical correlation existing between Hb and body mass index (BMI), Ccr, HbA1c, albuminuria or retinopathy, multiple regression analysis was performed. Serum EPO, Fe, TIBC, LDH and TB levels and number of reticulocytes and MCV were within normal limits. Multiple regression analysis disclosed that HbA1c, nephropathy evaluated by albuminuria and Ccr, and retinopathy has no concern with Hb level. There is only significant relationship between Hb levels and CVR-R. Similar results were obtained even if we analyzed a group of male and female separately. We conclude that CVR-R has the strong relationship on anemia without overt nephropathy in type 1 diabetes, indicating that autonomic failure contributes on the progression of anemia via a poor response of EPO to anemia.

A novel thymoma-associated autoimmune disease: Anti-PIT-1 antibody syndrome.

Anti-PIT-1 antibody syndrome has recently been reported and characterized by acquired growth hormone (GH), prolactin (PRL), and thyroid-stimulating hormone (TSH) deficiencies associated with autoimmunity to a pituitary specific transcription factor PIT-1, which plays an essential role in GH-, PRL-, and TSH-producing cells. Although circulating anti-PIT-1 antibody and PIT-1-reactive cytotoxic T cells (CTLs) were detected in the patients, the pathophysiology and precise mechanisms for the autoimmunity remain unclarified. During the follow up, thymoma was diagnosed in all 3 cases with anti-PIT-1 antibody syndrome. Immunohistochemical analysis revealed that PIT-1 was strongly expressed in neoplastic cortical thymic epithelial cells. Importantly, after thymectomy, the titer of anti-PIT-1 antibody decreased and reactivity of CTLs toward PIT-1 diminished. These data strongly suggest that the aberrant expression of PIT-1 in the thymoma plays a causal role in the development of this syndrome. Thus, we define that this syndrome is a novel thymoma-associated autoimmune disease.

Identification and functional analysis of the novel S179R POU1F1 mutation associated with combined pituitary hormone deficiency.

CONTEXT: The pituitary-specific transcription factor 1 plays a key role in the development and differentiation of three pituitary cell types: somatotrophs, lactotrophs, and thyrotrophs. Several mutations of the human gene (called POU1F1) have been shown to be responsible for a phenotype of combined pituitary hormone deficiency involving GH, prolactin (PRL), and TSH. OBJECTIVE: We have identified a novel homozygous C to G mutation in exon 4 of the POU1F1 gene (S179R) in a patient with this rare phenotype. We analyzed the functional consequences of this S179R mutation associated with a single-amino acid change in the POU-specific domain. METHODS: Consequences of this mutation on transcriptional activities by transfection studies in alphaT3 cells, DNA binding ability by EMSA, structural properties, and nuclear accumulation of POU1F1 were investigated. RESULTS: The transactivation capacity of this mutant was markedly decreased on the GH1, PRL, TSHbeta, and POU1F1 genes. Interestingly, this mutation abolished the functional interaction of POU1F1 on the PRL promoter with the coactivator cAMP response element-binding protein-binding protein but not with the transcription factor LIM homeodomain transcription factor 3. The S179R mutant displayed normal nuclear accumulation but a markedly decreased binding to a DNA response element in keeping with crystallographic data, suggesting that the S179R mutation might interfere with DNA binding. CONCLUSIONS: Together with previous data, our study indicates that both DNA binding and interaction with cofactors like cAMP response element-binding protein-binding protein are critical for POU1F1 function and that functional and structural properties of abnormal POU1F1 proteins are variously influenced by the type of mutations.