bluuebunny/crossref_metadata_2025 huggingface dataset:
Microvascular Effects of CRH in Human Skin Vary in Relation to Gender
Authors: Clifton V. L. , Crompton R. , Smith R. , Wright Ian M. R.
Published: January 2014

Males and females have a significantly different life expectancy because of the cardioprotective effects of estrogen. The mechanisms that result in this difference between the sexes are not fully understood. However, stress is a contributing factor to the development of cardiovascular disease, and stress-related factors derived from central or peripheral sources may have differential effects in the modulation of cardiovascular function in males and females. CRH is a central modulator of the stress response and is known to have vasodilator effects in a number of vascular beds. We have examined whether CRH has vasodilator effects in human skin and whether this effect is different between males and females using laser Doppler and iontophoresis. CRH (1 nm) had vasodilatory effects in the skin circulation of both premenopausal females (n = 6) and age-matched males (n = 5), but CRH-induced dilation was significantly more potent in females than males. Acetylcholine-(1 nm) and sodium nitroprusside- (0.74 nm) induced dilation was not significantly different between males (n = 6) and females (n = 6). This is the first study to demonstrate that CRH acts locally as a vasodilator in human skin circulation and that this response is augmented in premenopausal females. The mechanism by which CRH causes dilation in human skin is presently unknown. However, these data suggest that CRH-induced dilation may be one mechanism by which cardiovascular risk is reduced in premenopausal women.
Effects of Dose and Gender on the Growth and Growth Factor Response to GH in GH-Deficient Children: Implications for Efficacy and Safety
Authors: Cohen Pinchas , Bright George M. , Rogol Alan D. , Kappelgaard Anne-Marie , Rosenfeld Ron G. ,   on behalf of the American Norditropin Clinical Trials Group
Published: January 2014

We evaluated the dose-response effects of GH on the growth and growth factor levels of GH-deficient patients. One hundred eleven short (−3.0 ± 0.9 height sd score), prepubertal GH-deficient children were randomized to receive low- (L; 0.025 mg/kg per day), medium- (M; 0.05 mg/kg per day), or high- (H; 0.1 mg/kg per day) dose GH. One hundred four children completed the 2-yr study. At 2 yr, the three groups displayed increases in height sd scores of 1.4 ± 0.1 for L, 2.2 ± 0.1 for M, and 2.3 ± 0.1 for H (P < 0.001 relative to L, P = NS relative to M). The serum levels of IGF-I and IGF binding protein-3 during treatment also demonstrated dependency on the GH dose and were independently correlated with the increase in height sd scores attained. Bone age advancement, the occurrence of puberty, fasting glucose, and hemoglobin A1c did not change during therapy, but fasting insulin levels rose in a dose-dependent manner. Surprisingly, the GH dose-response curve for both auxological and biochemical parameters differed between prepubertal females (n = 33) and males (n = 71). Males had a linear GH dose response, whereas females had an apparent plateau of both linear growth and IGF-I sd score responses at 0.05 mg/kg per day. In this large, randomized, 2-yr study, we observed a dose-response effect of GH on growth and serum growth factor levels and a prepubertal gender difference in GH sensitivity. These results suggest that the efficacy and theoretical safety of GH therapy can be optimized by modulating the GH dose in a gender-specific manner, based on the growth response and serum growth factor levels.
Efficacy of the New Long-Acting Formulation of Lanreotide (Lanreotide Autogel) in the Management of Acromegaly
Authors: Caron Ph. , Beckers A. , Cullen D. R. , Goth M. I. , Gutt B. , Laurberg P. , Pico A. M. , Valimaki M. , Zgliczynski W.
Published: January 2014

Lanreotide Autogel is a new long-acting aqueous preparation of lanreotide for the treatment of acromegaly and is administered by deep sc injection from a small volume, prefilled syringe. The aim of this study was to evaluate the efficacy and safety of this new long-acting formulation in a large population of acromegalic patients previously responsive to lanreotide 30 mg, im (sustained release microparticle formulation). Lanreotide Autogel was administered by deep sc injection every 28 d to 107 patients (54 males and 53 females; mean age, 54 ± 1.2 yr). All patients had been treated with lanreotide (30 mg) for at least 3 months before study entry and had a mean GH level less than 10 ng/ml after at least 4 subsequent im injections every 14 d (48%), 10 d (32%), or 7 d (20%). Treatment was switched from lanreotide 30 mg injected every 14, 10, or 7 d to 60, 90, or 120 mg lanreotide Autogel, respectively, every 28 d. After three fixed dose injections of lanreotide Autogel, mean lanreotide levels were similar to those obtained at steady state with lanreotide 30 mg. During lanreotide Autogel treatment, the control of acromegalic symptoms was comparable with that previously achieved during lanreotide 30 mg treatment. After 3 injections of lanreotide Autogel, mean GH (2.87 ± 0.22 ng/ml) and IGF-I (317 ± 15 ng/ml) values were comparable with those recorded at the end of lanreotide 30 mg treatment (GH, 2.82 ± 0.19 ng/ml; IGF-I, 323 ± 16 ng/ml). GH levels below 2.5 ng/ml and age-/sex-normalized IGF-I were achieved in 33% and 39% of patients during lanreotide 30 mg and lanreotide Autogel treatment, respectively. Diarrhea, abdominal pain, and nausea were reported by 38%, 22%, and 18% of patients during lanreotide 30 mg treatment and by 29%, 17%, and 9% of patients, respectively, during lanreotide Autogel treatment. In conclusion, this clinical study shows that lanreotide Autogel is at least as efficacious and well tolerated as lanreotide 30 mg. This new long-acting lanreotide formulation, lanreotide Autogel, which is administered from a small volume, prefilled syringe by deep sc injection, is therefore likely to improve the acceptability of medical treatment for patients requiring long-term somatostatin analog therapy.
Hexoneogenesis in the Human Breast during Lactation
Authors: Sunehag Agneta L. , Louie Kathryn , Bier Jessica L. , Tigas Stelios , Haymond Morey W.
Published: January 2014

Lactose is the major osmotic agent in milk. Therefore, lactose synthesis indirectly regulates milk volume. The aim of this study was to determine the source of glucose and galactose in lactose. Six healthy lactating women were studied twice, during a 24-h fast and during ingestion of a mixed macronutrient drink (Sustacal) using [U-13C]glucose and [2-13C]glycerol. Six additional lactating women were studied on one single occasion during ingestion of glucose labeled with [1-13C]glucose.

Using the ratios of [13C6] enrichments of glucose in lactose and plasma glucose and that of galactose in lactose and plasma glucose, we determined that 98 ± 3% of glucose and 68 ± 7% of galactose in lactose were derived from plasma glucose in the fed state, and 72 ± 4 and 51 ± 3%, respectively, after a 24-h fast. Virtually identical results (97 ± 6 and 64 ± 4%, respectively) were obtained during the glucose feeding study. On the basis of the [13C1] enrichment of glucose and galactose in lactose (derived from [2-13C]glycerol), glycerol contributes to the production of galactose but not glucose within the breast.

Thus, plasma glucose is an important source of lactose, but significant amounts of glucose and galactose in lactose are generated within the breast, a process denoted hexoneogenesis. In this process, glycerol is a precursor for milk galactose but not glucose.
Detection of Insulin Resistance by Simple Quantitative Insulin Sensitivity Check Index QUICKI for Epidemiological Assessment and Prevention
Authors: Hřebíček Jiří , Janout Vladimír , Malinčíková Jana , Horáková Dagmar , Čížek Luděk
Published: January 2014

The aim of the present study was to evaluate the recently defined simple insulin sensitivity check index QUICKI (Katz et al. 2000) for insulin resistance diagnostics in common clinical and epidemiological practice. Both the QUICKI (1/log insulin + log glycemia in mg/dL) and HOMA (insulin * glycemia in μmol/L/22.5) indexes were calculated from fasting values in 259 adult healthy volunteers and patients, and in 47 healthy and obese children of prepubertal age of both sexes. In adults, a fall in the QUICKI index (mean ± SEM in healthy subjects = 0.366 ± 0.029) as well as an increase in the HOMA index (in healthy subjects 1.57 ± 0.87) corresponded to metabolic and clinical manifestations of insulin resistance in various groups of outpatients. The QUICKI index had lower dispersion variances and the 95% confidence limits displayed a higher discrimination capacity. Patients with glucose intolerance or diabetes, hyperlipidemia typical for insulin resistance, or with combination of these metabolic disorders were characterized by QUICKI index values that were significantly lower than those of healthy volunteers. The QUICKI index in healthy prepubertal children indicated a higher insulin resistance compared to adults (mean 0.339 ± 0.020); an increase in the QUICKI index in obese children with BMI over 25 was not significant, although obese children showed a significant increase of serum leptin and triglycerides and a decrease of HDL-cholesterol. Adult patients with QUICKI index below 0.357 (which is at the lower limit of 95% confidence limits in healthy persons) represented a group with typical manifestations of metabolic syndrome, differing in these parameters significantly from the group of patients of comparable age with a QUICKI index greater than 0.357. The present study suggests suitability of the QUICKI index for diagnosis of insulin resistance in clinical and epidemiological practice. However, a normal QUICKI index range needs to be established for each laboratory with an appropriate control group because of significant interlaboratory variations in insulin determinations and/or possible differences in various populations.
Insulin Resistance Is Associated with Increased Circulating Level of Thrombin-Activatable Fibrinolysis Inhibitor in Type 2 Diabetic Patients
Authors: Hori Yasuko , Gabazza Esteban C. , Yano Yukata , Katsuki Akira , Suzuki Koji , Adachi Yukihiko , Sumida Yasuhiro
Published: January 2014

Hypofibrinolysis is a common finding in patients with diabetes mellitus (DM) and obesity and a risk factor for the development of cardiovascular disease. Recently, a new potent inhibitor of fibrinolysis, the thrombin-activatable fibrinolysis inhibitor (TAFI) has been isolated and characterized from human plasma. The present study was undertaken to assess the activity and circulating level of TAFI and its relation to fibrinolytic function and obesity in patients with type 2 DM. Fifty-seven patients with type 2 DM (38 men, 19 women) were enrolled in this study. DM patients were categorized in age-matched obese [body mass index (BMI) ≥ 25] and nonobese (BMI < 25) groups. The plasma concentration and activity of TAFI were significantly (P < 0.05) higher in DM patients than in healthy controls. The plasma levels and activity of TAFI were significantly (P < 0.05) elevated in obese DM patients compared with nonobese DM and nonobese healthy subjects. RT-PCR demonstrated the expression of TAFI in human adipose tissue and in human endothelial cells. The plasma levels of TAFI were independently and significantly correlated with glucose intolerance (HbA1c), with obesity (BMI, visceral fat area), and with an indicator of insulin resistance (glucose infusion rate). This study showed that increased circulating level of TAFI may be an important causative factor of hypofibrinolysis in patients with type 2 diabetes, obesity and insulin resistance.
Selenium Supplementation in Patients with Autoimmune Thyroiditis Decreases Thyroid Peroxidase Antibodies Concentrations
Authors: Gärtner Roland , Gasnier Barbara C. H. , Dietrich Johannes W. , Krebs Bjarne , Angstwurm Matthias W. A.
Published: January 2014

In areas with severe selenium deficiency there is a higher incidence of thyroiditis due to a decreased activity of selenium-dependent glutathione peroxidase activity within thyroid cells. Selenium-dependent enzymes also have several modifying effects on the immune system. Therefore, even mild selenium deficiency may contribute to the development and maintenance of autoimmune thyroid diseases. We performed a blinded, placebo-controlled, prospective study in female patients (n = 70; mean age, 47.5 ± 0.7 yr) with autoimmune thyroiditis and thyroid peroxidase antibodies (TPOAb) and/or Tg antibodies (TgAb) above 350 IU/ml. The primary end point of the study was the change in TPOAb concentrations. Secondary end points were changes in TgAb, TSH, and free thyroid hormone levels as well as ultrasound pattern of the thyroid and quality of life estimation. Patients were randomized into 2 age- and antibody (TPOAb)-matched groups; 36 patients received 200 μg (2.53 μmol) sodium selenite/d, orally, for 3months, and 34 patients received placebo. All patients were substituted with l-T4 to maintain TSH within the normal range. TPOAb, TgAb, TSH, and free thyroid hormones were determined by commercial assays. The echogenicity of the thyroid was monitored with high resolution ultrasound. The mean TPOAb concentration decreased significantly to 63.6% (P = 0.013) in the selenium group vs. 88% (P = 0.95) in the placebo group. A subgroup analysis of those patients with TPOAb greater than 1200 IU/ml revealed a mean 40% reduction in the selenium-treated patients compared with a 10% increase in TPOAb in the placebo group. TgAb concentrations were lower in the placebo group at the beginning of the study and significantly further decreased (P = 0.018), but were unchanged in the selenium group. Nine patients in the selenium-treated group had completely normalized antibody concentrations, in contrast to two patients in the placebo group (by χ2 test, P = 0.01). Ultrasound of the thyroid showed normalized echogenicity in these patients. The mean TSH, free T4, and free T3 levels were unchanged in both groups.

We conclude that selenium substitution may improve the inflammatory activity in patients with autoimmune thyroiditis, especially in those with high activity. Whether this effect is specific for autoimmune thyroiditis or may also be effective in other endocrine autoimmune diseases has yet to be investigated.
Hypersecretion of FSH in Infant Boys and Girls Born Small for Gestational Age
Authors: Ibáñez Lourdes , Valls Carme , Cols Maria , Ferrer Angela , Marcos Maria Victoria , de Zegher Francis
Published: January 2014

Prenatal growth restraint, as reflected in a low birthweight for gestational age, is a risk factor for postpubertal FSH hypersecretion and for reduced gonadal size. The ontogeny of the low-birthweight effect on the FSH-inhibin B feedback loop is unknown. Infancy is an episode of choice to study the possibility of an early low-birthweight effect on the FSH-inhibin B loop because this phase is characterized by high activity within the gonadal axis.

We assessed serum concentrations of FSH and inhibin B in 46 infants [26 girls and 20 boys; mean age, 4 months; range, 3–6 months; 17 appropriate for gestational age (AGA), 29 small for gestational age (SGA); mean birthweight, 3.2 kg for AGA vs. 2.3 kg for SGA], together with circulating levels of LH, E2, and free androgen index.

In SGA girls and boys, serum FSH levels were 2- and 4-fold higher (P < 0.001), respectively, than in AGA controls of the same gender (7.3 ± 0.9 vs. 3.8 ± 0.4 IU/ml and 2.9 ± 0.5 vs. 0.7 ± 0.2 IU/ml). Serum LH, inhibin B, and free androgen index/E2 concentrations were similar in AGA and SGA infants.

In conclusion, prenatal growth restraint was found to be followed by elevated serum FSH concentrations in infant girls and boys. SGA infants seem to need an augmented FSH drive to fulfill inhibin B requirements on the afferent side of the feedback loop. The late-endocrine correlates of early growth restraint are herewith extended to include the main axis of reproduction in both genders. It remains to be studied whether FSH hypersecretion in infancy is a marker of subsequent subfertility.
Follicle-Stimulating Hormone Activates Mitogen-Activated Protein Kinase in Preneoplastic and Neoplastic Ovarian Surface Epithelial Cells
Authors: Choi Kyung-Chul , Kang Sung Keun , Tai Chen-Jei , Auersperg Nelly , Leung Peter C. K.
Published: January 2014

To investigate the role of FSH in ovarian cancer development, the present study examined the expression of FSH receptor (FSH-R) and the effect of FSH on proliferation of normal, preneoplastic, and neoplastic ovarian surface epithelium (OSE) cells. Recently, immortalized OSE (IOSE) cell lines, including IOSE-29 (preneoplastic) and IOSE-29EC (neoplastic), were used. Our results indicated that FSH-R mRNA was expressed and that FSH exerted a growth stimulatory effect in normal, preneoplastic, and neoplastic OSE cells. To investigate the mechanism of the growth stimulatory effect, the activation of MAPKs by FSH was examined in preneoplastic and neoplastic OSE cells. Treatment with FSH resulted in MAPK activation of IOSE-29 and IOSE-29EC cells, whereas the stimulatory effect of FSH on cellular proliferation and MAPK activation was completely abolished in the presence of PD98059, a MAPK kinase inhibitor, suggesting that the growth stimulatory effect of FSH is mediated through MAPK activation in these OSE cells. In a time-dependent study, FSH significantly increased MAPK activity at 5–10 min in IOSE-29 cells. The activated MAPK declined to the control level after 20 min in these cells. Similarly, treatment with FSH significantly induced MAPK activation after 5 min and sustained it for 60 min in IOSE-29EC cells. In addition, treatment with FSH resulted in substantial phosphorylation of Elk-1, confirming that FSH action is mediated via activation of MAPK. In conclusion, we have demonstrated that FSH-R was expressed, and FSH induced growth stimulation in normal, preneoplastic, and neoplastic OSE cells. Furthermore, treatment with FSH stimulated activation of the MAPK cascade and phosphorylated Elk-1 in neoplastic OSE cells. These results suggest that the MAPK cascade may be involved in cellular functions such as growth stimulation in response to FSH in preneoplastic and neoplastic OSE cells.
Human Resistin Gene: Molecular Scanning and Evaluation of Association with Insulin Sensitivity and Type 2 Diabetes in Caucasians
Authors: Wang Hua , Chu Winston S. , Hemphill Chris , Elbein Steven C.
Published: January 2014

Insulin resistance is strongly associated with obesity, but even among obese subjects insulin sensitivity varies widely. Recently, a new adipocyte hormone, resistin, was identified, shown to reduce insulin-mediated glucose uptake, and shown to be increased in obese mice. We used the chromosome 19 draft sequence to determine the genomic structure of human resistin and to screen the exons, introns, and flanking sequences for variation. We screened 44 subjects with type 2 diabetes and 20 nondiabetic family members who were at the extremes of insulin sensitivity. We identified eight noncoding single nucleotide polymorphisms (SNPs) and one GAT microsatellite repeat. Three SNPs, which were in incomplete linkage disequilibrium with each other and had allelic frequencies exceeding 5%, were selected for further study. No SNP was associated with type 2 diabetes, but the SNP in the promoter region was a significant determinant of insulin sensitivity index (P = 0.04) among nondiabetic family members who had undergone iv glucose tolerance tests. The three common SNPs showed statistical significance as determinants of insulin sensitivity index (P < 0.01) in interaction with body mass index. Noncoding SNPs in the resistin gene may influence insulin sensitivity in interaction with obesity, but this finding will need to be confirmed in other populations.
Uterine Glands Provide Histiotrophic Nutrition for the Human Fetus during the First Trimester of Pregnancy
Authors: Burton Graham J. , Watson Adrian L. , Hempstock Joanne , Skepper Jeremy N. , Jauniaux Eric
Published: January 2014

Providing adequate nutrition to the fetus is key to a successful pregnancy. The interstitial form of implantation displayed by the human blastocyst is generally associated with early onset of maternal blood flow to the developing placenta, and hence hemotrophic exchange. However, the recent finding that the maternal intraplacental circulation is not fully established until the third month of gestation suggests that human fetal nutrition may be initially histiotrophic. We therefore investigated activity of the uterine glands during early pregnancy. We demonstrate here that these glands remain active until at least wk 10 of pregnancy, and that their secretions are delivered freely into the placental intervillous space. We also demonstrate phagocytic uptake by the placental syncytiotrophoblast of two glycoproteins, the mucin MUC-1 and glycodelin A, synthesized in the maternal glands. Glycodelin was also detected within the epithelium of the secondary yolk sac lining the exocoelomic cavity, indicating that the yolk sac may play an important role in nutrient exchange before vascularisation of the chorionic villi. Our findings demonstrate that the uterine glands are an important source of nutrients during organogenesis, when metabolism is essentially anaerobic.
Regulated Expression of Signal Transducer and Activator of Transcription, Stat5, and its Enhancement of PRL Expression in Human Endometrial Stromal Cells in Vitro
Authors: Mak I. Y. H. , Brosens J. J. , Christian M. , Hills F. A. , Chamley L. , Regan L. , White J. O.
Published: January 2014

Differentiation of human endometrium during the secretory phase of the menstrual cycle is characterized by expression of a variety of genes implicated in the establishment and maintenance of pregnancy. An increased abundance of signal transducers and activators of transcription (Stats) in the secretory phase suggests Stat5 as a component of the differentiation of endometrium in response to ovarian hormone stimulation in vivo. Decidualization is initiated in a subset of endometrial stromal cells (ESC) in vivo during the secretory phase, but it is unclear whether regulated expression of Stat5 is a feature of these cells. Here, therefore, the abundance and subcellular distribution of Stat5 in ESC after a decidualization stimulus of cAMP plus medroxyprogesterone acetate (MPA) has been investigated in vitro. Western blotting revealed an increase in the apparent abundance of Stat5a and Stat5b, in the cytosolic and nuclear fractions, at 2, 3, and 4 d after stimulation. The potential functional relevance of this increase in Stat5 is suggested by the ability of transiently transfected Stat5a or Stat5b to significantly enhance the response of the decidual PRL promoter to cAMP/MPA and attenuation of the response to cAMP/MPA by dominant negative Stat5. Recent evidence suggests endometrial differentiation, including PRL production, as a possible target of antiphospholipid antibodies (aPL) prevalent in recurrent miscarriage. Monoclonal antibody, ID2, which has similar reactivity as human aPL, significantly decreased the apparent abundance of nuclear Stat5b in response to cAMP/MPA and was associated with decreased decidual PRL promoter activation and PRL secretion. Regulated expression of Stat5 is therefore a component of decidual differentiation of human ESC and contributes significantly to activation of the decidual PRL promoter. Alteration of this process by an aPL component suggests decidual differentiation as a potential clinical target in recurrent early miscarriages.
Body Composition, IGF-I and IGFBP-3 Concentrations as Outcome Measures in Severely GH-Deficient (GHD) Patients after Childhood GH Treatment: A Comparison with Adult Onset GHD Patients
Authors: Attanasio Andrea F. , Howell Simon , Bates Peter C. , Frewer Paul , Chipman John , Blum Werner F. , Shalet Stephen M.
Published: January 2014

If GH therapy of children with GH deficiency (GHD) has been adequate, body composition should be comparable to that of patients who have undergone normal childhood development and become hypopituitary thereafter. To assess this, body composition was determined in 92 patients with childhood onset (CO) GHD, aged 18–30 yr, who had been treated to final height with GH for 8.98 ± 4.30 yr and had stopped treatment 1.57 ± 1.20 yr previously, but who remained GHD (assessed by a GH stimulation test and IGF-I values). These were compared with 35 age-matched GH-naïve hypopituitary patients with adult onset (AO) GHD. Lean body mass, fat mass, and total bone mineral content were assessed by dual energy x-ray absorptiometry and corrected for actual height. CO patients were shorter (CO height, −1.18 ± 1.16 sd score; AO height, −0.38 ± 1.12 sd score; P < 0.001) and had lower body mass index (CO, 23.19 ± 5.76 kg/m2; AO, 28.9 ± 6.27 kg/m2; P < 0.001) than the AO group. Although there were gender differences, within genders CO patients had lower lean body mass, fat mass, and bone mineral content (P < 0.001 in all cases) compared with AO patients. Standard deviation scores for IGF-I (CO female, −9.2 ± 3.1; AO female, −5.2 ± 2.6; CO male, −6.4 ± 2.7; AO male, −3.5 ± 2.3; P < 0.001 within each gender) and IGFBP-3 (CO female, −3.5 ± 2.5; AO female, −1.7 ± 1.5; CO male, −2.8 ± 2.0; AO male, −1.1 ± 1.6; P < 0.001 within each gender) were significantly lower in the CO group. These results suggest that patients with CO GHD who were treated to final height suffer a significant maturational deficit despite GH replacement during childhood.
Hydrochlorothiazide Effectively Reduces Urinary Calcium Excretion in Two Japanese Patients with Gain-of-Function Mutations of the Calcium-Sensing Receptor Gene
Authors: Sato Kohei , Hasegawa Yukihiro , Nakae Jun , Nanao Kenji , Takahashi Ikuko , Tajima Toshihiro , Shinohara Nozomi , Fujieda Kenji
Published: January 2014

Gain-of-function mutations of the calcium-sensing receptor (CaR) gene cause autosomal dominant and/or sporadic hypocalcemia with hypercalciuria. Because treatment of the hypocalcemia with vitamin D and/or calcium in patients with such mutations results in increased hypercalciuria, nephrocalcinosis, and renal impairment, its use should be limited to alleviating the symptoms of symptomatic patients. Because thiazide diuretics have been successfully used to treat patients with hypercalciuria and hypoparathyroidism, they are theoretically useful in reducing urine calcium excretion and maintaining serum calcium levels in patients with gain-of-function mutations of the CaR gene. In this study, we report on the clinical course, molecular analysis, and effects of hydrochlorothiazide therapy in two Japanese patients with gain-of-function mutations of the CaR gene. Within a few weeks after birth, they developed generalized tonic seizures due to hypocalcemia (serum calcium values: 1.1 mmol/liter and 1.3 mmol/liter, respectively). Despite treatment with the standard dose of 1,25-dihydroxyvitamin D3 in one patient and 1α-hydroxyvitamin D3 in the other, acceptable serum calcium levels near the lower limit of normal were not established, and their urinary calcium excretion inappropriately increased. Addition of hydrochlorothiazide (1 mg/kg) reduced their urinary calcium excretion and maintained their serum calcium concentrations near the lower limit of normal, allowing the 1,25-dihydroxyvitamin D3 and 1α-hydroxyvitamin D3 doses to be reduced, and it alleviated their symptoms. A heterozygous missense mutation was identified in both patients. In one patient, the mutation was A843E in the seventh transmembrane domain of the CaR, and in the other it was L125P in the N-terminal extracellular domain. In vitro transient transfection of their mutant CaR cDNAs into HEK293 cells shifted the concentration-response curve of Ca2+ to the left.

In conclusion, two sporadic cases of hypercalciuric hypocalcemia were due to de novo gain-of-function mutations of the CaR gene. Hydrochlorothiazide with vitamin D3 successfully reduced the patients’ urinary calcium excretion and controlled their serum calcium concentrations and symptoms. Thiazide diuretics are effective in patients with gain-of function mutations of the CaR gene.
Human Chorionic Gonadotropin-Induced Ovarian Hyperstimulation Syndrome Is Associated with Up-Regulation of Vascular Endothelial Growth Factor
Authors: Wang Tzu-Hao , Horng Shang-Gwo , Chang Chia-Lin , Wu Hsien-Ming , Tsai Yi-Ju , Wang Hsin-Shih , Soong Yung-Kuei
Published: January 2014

Ovarian hyperstimulation syndrome (OHSS), a life-threatening complication occurring in stimulated ovarian cycles, arises from treatment with gonadotropin for induction of follicular maturation in infertile women. Clinical characteristics of OHSS include ascites and pleural effusion induced by increased vascular permeability, where vascular endothelial growth factor (VEGF) was suspected to be the culprit. To test whether the effects of human CG (hCG) on the pathogenesis of OHSS were mediated through the VEGF produced by luteinized granulosa cells, we measured estradiol, VEGF, IGF-II levels in serum, and follicular fluid and analyzed their mRNA expression in luteinized granulosa cells obtained from 101 women (58 with OHSS and 43 controls) who underwent in vitro fertilization and embryo transfer. This study presents the first evidence that hCG up-regulated VEGF expression of granulosa cells in the OHSS, not the control groups, and that follicular VEGF worked through an autocrine mechanism using its kinase insert domain-containing receptor, not the fms-like tyrosine kinase receptor. We calculated total follicular production of VEGF, by multiplying follicular concentrations by follicular volumes, and verified that an increase in total follicular production of VEGF accounted for elevated serum levels of VEGF, which was associated with the development of OHSS. These findings demonstrate that through up-regulation of VEGF, hCG plays a significant role in the pathogenesis of OHSS.
Pendrin Is an Iodide-Specific Apical Porter Responsible for Iodide Efflux from Thyroid Cells
Authors: Yoshida Akio , Taniguchi Shinichi , Hisatome Ichiro , Royaux Ines E. , Green Eric D. , Kohn Leonard D. , Suzuki Koichi
Published: January 2014

The Pendred syndrome gene encodes a 780-amino acid putative transmembrane protein (pendrin) that is expressed in the apical membrane of thyroid follicular cells. Although pendrin was shown to transport iodide and chloride using Xenopus laevis oocytes and Sf9 insect cells, there is no report using mammalian cells to study its role in thyroid function. We show here, using COS-7 cells and Chinese hamster ovary cells transfected with expression vectors encoding sodium iodide symporter or human Pendred syndrome gene cDNA and by comparison with studies using rat thyroid FRTL-5 cells, that pendrin is an iodide-specific transporter in mammalian cells and is responsible for iodide efflux in the thyroid.
The Corticotropin-Releasing Hormone Stimulation Test in White Coat Hypertension
Authors: Tabeta Isao , Ueshiba Hajime , Ichijo Takamasa , Hiroi Naoki , Yakushiji Fumiatu , Simojo Masako , Tsuboi Kumiko , Miyachi Yukitaka
Published: January 2014

This study was undertaken to clarify the status of the ACTH and cortisol responses to CRH in patients with white coat hypertension. White coat hypertension was defined as a difference between clinic blood pressure and ambulatory blood pressure of at least 20 mm Hg for systolic blood pressure and/or 10 mm Hg for diastolic blood pressure. CRH stimulation tests were performed between 1400 and 1700 h in 11 patients with white coat hypertension (4 males and 7 females) and 11 normal subjects (4 males and 7 females). Blood pressure and heart rate were measured 15 min before, at time zero, and 15, 30, 60, and 120 min after initiation of the CRH stimulation tests. In white coat hypertension, both the mean systolic blood pressure (162 ± 15 mm Hg) and diastolic blood pressure (97 ± 10 mm Hg) were higher than in controls (P < 0.01) on 3 occasions. The mean ambulatory blood pressure for the 24-h period of the test did not differ between patients with white coat hypertension and normal subjects. Basal levels of ACTH and cortisol did not differ between patients with white coat hypertension and control subjects. However, challenge with CRH elevated ACTH (30 min) and cortisol (30, 60, and 120 min) to levels higher than those in controls, with the net increase in both ACTH and cortisol being higher than that in controls over the study period (P < 0.01). These significant responses suggest that white coat hypertension is associated with hypothalamic-pituitary-adrenal hypersensitivity to stressors.
Size and Oxidative Susceptibility of Low-Density Lipoprotein Particles in Breast Cancer Patients with Tamoxifen-Induced Fatty Liver
Authors: Wakatsuki Akihiko , Ogawa Yasuhiro , Saibara Toshiji , Okatani Yuji , Fukaya Takao
Published: January 2014

The purpose of the present study was to investigate the effects of tamoxifen on the size and oxidative susceptibility of low-density lipoprotein (LDL) particles in breast cancer patients with tamoxifen-induced fatty liver. We investigated the following breast cancer patients: 13 receiving no tamoxifen (group A), 13 receiving tamoxifen 40 mg daily but without fatty liver (group B), and 13 receiving tamoxifen 40 mg daily with fatty liver (group C). Plasma lipids and diameter of LDL particles were measured. Susceptibility of LDL to oxidation was analyzed by incubation with CuSO4 while monitoring conjugated diene formation and assaying thiobarbituric acid reactive substances (TBARS). Plasma total and LDL cholesterol concentrations in groups B and C were significantly lower than those in group A. In group C, concentrations of plasma triglyceride (TG) and TBARS were significantly greater, but LDL particle diameter and lag time for LDL oxidation were significantly smaller than those in groups A and B. Plasma TG concentrations correlated negatively with computed tomography ratio of liver to spleen (r = −0.76; P < 0.001). LDL particle diameter correlated negatively with plasma TG (r = −0.62; P < 0.001) and TBARS (r = −0.44; P < 0.01), but positively with LDL lag time (r = 0.47; P < 0.01). Tamoxifen-induced fatty liver in breast cancer patients may be atherogenic, via increased TG and consequent small, easily oxidized LDL particles.
A Prospective Controlled Study of the Impact of Hyperthyroidism on Reproductive Function in Males
Authors: Krassas G. E. , Pontikides N. , Deligianni V. , Miras K.
Published: January 2014

The aim of this prospective controlled study was to ascertain the effect of hyperthyroidism on sperm quality and composition. We studied 23 thyrotoxic male patients, aged 43.8 ± 2.4 yr (mean ± sem), and 15 healthy male controls of approximately the same age (42.2 ± 2.2 yr). Two semen analyses at intervals of 2–3 wk were obtained before and about 5 months after euthyroidism was achieved either by methimazole alone (14 patients) or 131I plus methimazole (9 patients). Total fructose, zinc (Zn), and magnesium (Mg) were also measured in seminal plasma in 16 patients, because 7 had semen volume less than 2 ml. In the control group semen analysis was performed only once. Mean (±sem) semen volume was within normal range both in patients (3.3 ± 0.2 ml) and controls (3.5 ± 0.4 ml; P = NS). Mean sperm density was lower in patients, although the difference compared with controls did not reach statistical significance (35.7 ± 5.3 vs. 51.5 ± 6.1 × 106/ml; P = 0.062). The same was found with sperm morphology (68 ± 7% vs. 78 ± 8%; P = NS). Finally, mean motility was lower in thyrotoxic males than in controls (28 ± 8% vs. 57 ± 7%; P < 0.01). After treatment, sperm density and motility improved [35.7 ± 5.3 vs. 43.3 ± 6.5 × 106/ml (P = NS) and 28 ± 8% vs. 45 ± 7% (P < 0.05), respectively], but sperm morphology did not change (68 ± 7% vs. 70 ± 6%; P = NS). Mean values for fructose, Zn, and Mg did not differ between controls and patients either before or after achievement of euthyroidism [9.2 ± 0.7, 3.0 ± 0.5, and 4.2 ± 0.7 nmol/liter vs. 8.6 ± 0.9, 3.0 ± 0.5, and 4.7 ± 0.8 nmol/liter (patients before) and 9.1 ± 0.7, 3.1 ± 0.6, and 4.5 ± 0.9 nmol/liter (patients after treatment) for fructose, Zn, and Mg, respectively]. Moreover, according to the treatment given, no statistically significant differences were found before or after treatment. Finally, seminal plasma fructose, Zn, and Mg levels did not correlate with sperm parameters or with pretreatment thyroid hormone levels. In conclusion, the results of our study indicate that male patients with hyperthyroidism have abnormalities in seminal parameters, mainly sperm motility. These abnormalities improve or normalize when the patients become euthyroid. Restoration of sperm parameters was independent of the treatment provided for the hyperthyroid syndrome. Moreover, seminal plasma elements, such as fructose, Zn, and Mg, did not correlate with sperm density, motility, or morphology.
Transcriptional Repression of the α-Subunit Gene by Androgen Receptor Occurs Independently of DNA Binding but Requires the DNA-Binding and Ligand-Binding Domains of the Receptor
Authors: Heckert Leslie L. , Wilson Elizabeth M. , Nilson John H.
Published: January 2014

The pituitary glycoprotein hormones LH and FSH regulate the reproductive cycle and are sensitive to feedback by gonadal steroids. The common α-subunit shared by these hormones is transcriptionally repressed by androgen receptor (AR) in the presence of its ligand dihydrotestosterone. This identifies at least one mechanism that contributes to AR-dependent suppression of gonadotropin synthesis. Repression of α-subunit transcription by AR requires only the sequences within the first 480 bp of the promoter. While this region contains a high-affinity binding site for AR, this element does not mediate the suppressive effects of androgens. Instead, two other elements within the promoter-regulatory region (α-basal element and cAMP-regulatory element), which are important for expression of theα -subunit gene in gonadotropes, mediate the effects of AR. This suggests that AR inhibits activity of the α-subunit promoter by interfering with the transcriptional properties of the proteins that bind to α-basal element and the cAMP-regulatory elements. Furthermore, transfection analysis of various mutant ARs identified both the DNA-binding and ligand-binding domains of the receptor as critical for repression. Comparisons with the MMTV promoter revealed distinct structural requirements that underlie the transactivation and transrepression properties of AR.
Human and Murine Osteocalcin Gene Expression: Conserved Tissue Restricted Expression and Divergent Responses to 1,25-Dihydroxyvitamin D3in Vivo
Authors: Sims Natalie A. , White Christopher P. , Sunn Kate L. , Thomas Gethin P. , Drummond Melanie L. , Morrison Nigel A. , Eisman John A. , Gardiner Edith M.
Published: January 2014

Human and murine osteocalcin genes demonstrate similar cell-specific expression patterns despite significant differences in gene locus organization and sequence variations in cis-acting regulatory elements. To investigate whether differences in these regulatory regions result in an altered response to 1,25-dihydroxyvitamin D3[ 1,25-(OH)2D3] in vivo, we compared the response of the endogenous mouse osteocalcin gene to a bacterial reporter gene directed by flanking regions of the human osteocalcin gene in transgenic mice. Transgene expression colocalized with endogenous osteocalcin expression in serial sections, being detected in osteoblasts, osteocytes and hypertrophic chondrocytes. In calvarial cell culture lysates from transgenic and nontransgenic mice, the endogenous mouse osteocalcin gene did not respond to 1,25-(OH)2D3 treatment. Despite this, transgene activity was significantly increased in the same cells. Similarly, Northern blots of total cellular RNA and in situ hybridization studies of transgenic animals demonstrated a maximal increase in transgene expression at 6 h after 1,25-(OH)2D3 injection (23.6 ± 3.6-fold) with a return to levels equivalent to uninjected animals by 24 h (1.2 ± 0.1-fold). This increase in transgene expression was also observed at 6 h after 1,25-(OH)2D3 treatment in animals on a low calcium diet (25.2 ± 7.7-fold) as well as in transgenic mice fed a vitamin D-deficient diet containing strontium chloride to block endogenous 1,25-(OH)2D3 production (7.5 ± 0.9-fold). In contrast to the increased transgene expression levels, neither endogenous mouse osteocalcin mRNA levels nor serum osteocalcin levels were significantly altered after 1,25-(OH)2D3 injection in transgenic or nontransgenic mice, regardless of dietary manipulations, supporting evidence for different mechanisms regulating the response of human and mouse osteocalcin genes to 1,25-(OH)2D3. Although the cis- and trans-acting mechanisms directing cell-specific gene expression appear to be conserved in the mouse and human osteocalcin genes, responsiveness to 1,25-(OH)2D3 is not. The mouse osteocalcin genes do not respond to 1,25-(OH)2D3 treatment, but the human osteocalcin-directed transgene is markedly up-regulated under the same conditions and in the same cells. The divergent responses of these homologous genes to 1,25-(OH)2D3 are therefore likely to be due to differences in mouse and human osteocalcin-regulatory sequences rather than to variation in the complement of trans-acting factors present in mouse osteoblastic cells. Increased understanding of these murine-human differences in osteocalcin regulation may shed light on the function of osteocalcin and its regulation by vitamin D in bone physiology.
Loss of an Estrogen Receptor Isoform (ERαΔ3) in Breast Cancer and the Consequences of Its Reexpression: Interference with Estrogen-Stimulated Properties of Malignant Transformation
Authors: Erenburg I. , Schachter B. , Lopez R. Mira y , Ossowski L.
Published: January 2014

Comparison of mRNA ratios of a non-DNA-binding estrogen receptor (ERα) isoform, missing exon 3 (ERαΔ3), to the full-length ERα, in normal breast epithelium to that in primary breast cancers and breast cancer cell lines revealed a 30-fold reduction of this ratio in cancer cells (P < 0.0001). To test what functions may have been affected by the loss of ERαΔ3, stable clones of MCF-7 cells expressing ectopic ERαΔ3 protein, at the range of physiological ERα, were generated. In vector-transfected controls the ERαΔ3-mRNA and protein were less than 10% while in the ERαΔ3-expressing clones, ERαΔ3-mRNA and protein ranged from 36–76% of the total ERα. Estrogen (E2) stimulated the expression of pS2-mRNA in pMV7 vector control cells, but the stimulation was reduced by up to 93% in ERαΔ3-expressing clones. In addition, several properties associated with the transformed phenotype were also strongly affected when ERαΔ3 protein was reexpressed. Compared with vector-transfected control cells, the saturation density of the ERαΔ3-expressing clones was reduced by 50–68%, while their exponential growth rate was only slightly (14.5 ± 5%) lower. The in vivo invasiveness of the ERαΔ3-expressing cells was significantly reduced (P = 0.007) by up to 79%. E2 stimulated anchorage-independent growth of the pMV7 vector control cells, but reduced it to below baseline levels in ERαΔ3 clones. The reduction of the pS2 response to E2 in the ERαΔ3-expressing clones and the E2 block of anchorage-independent growth to below baseline were more pronounced than expected from the dominant negative function of ERαΔ3. These observations suggest that E2 may activate an additional ERαΔ3-dependent inhibitory pathway. The drastic reduction of ERαΔ3 to ERα ratio in breast cancer, and the fact that when present in breast cancer cells this isoform leads to a suppression, rather than enhancement, of the transformed phenotype by E2 suggests that the regulation of ERα-mRNA splicing may need to be altered for the breast carcinogenesis to proceed.
Activities in Pit-1 Determine Whether Receptor Interacting Protein 140 Activates or Inhibits Pit-1/Nuclear Receptor Transcriptional Synergy
Authors: Chuang F. Max , West Brian L. , Baxter John D. , Schaufele Fred
Published: January 2014

Pituitary-specific transcription of the evolutionarily related rat (r) GH and PRL genes involves synergistic interactions between Pit-1 and other promoter-binding factors including nuclear receptors. We show that Pit-1/thyroid hormone receptor (TR) and Pit-1/estrogen receptor (ER) synergistic activation of the rGH and rPRL promoters are globally similar. Both synergies depend upon the same activation functions in Pit-1 and also require activation function-2 conserved in TR and ER. The activation function-2 binding protein, RIP140, previously thought to be a nuclear receptor coactivator, strongly inhibits both Pit-1/TR and Pit-1/ER synergy. RIP140 inhibition is profoundly influenced, in a promoter-specific fashion, by a synergism-selective function in Pit-1: deletion of Pit-1 amino acids 72–100 switches RIP140 to an activator of Pit-1/ER and Pit-1/TR synergy at the rPRL promoter but not at the rGH promoter. Pit-1 amino acids 101–125 are required for RIP140 inhibition or activation again only at the rPRL promoter. Therefore, functions within one factor can determine the activity of a coactivator binding to its synergistic partner. This promoter context-specific synergistic interplay between transcription factors and coactivators is likely an essential determinant of cell-specific transcriptional regulation.
An Inhibitory Region of the DNA-Binding Domain of Thyroid Hormone Receptor Blocks Hormone-Dependent Transactivation
Authors: Liu Ying , Takeshita Akira , Nagaya Takashi , Baniahmad Aria , Chin William W. , Yen Paul M.
Published: January 2014

We have employed a chimeric receptor system in which we cotransfected yeast GAL4 DNA-binding domain/retinoid X receptor β ligand-binding domain chimeric receptor (GAL4RXR), thyroid hormone receptor-β (TRβ), and upstream activating sequence-reporter plasmids into CV-1 cells to study repression, derepression, and transcriptional activation. In the absence of T3, unliganded TR repressed transcription to 20% of basal level, and in the presence of T3, liganded TRβ derepressed transcription to basal level. Using this system and a battery of TRβ mutants, we found that TRβ/RXR heterodimer formation is necessary and sufficient for basal repression and derepression in this system. Additionally, an AF-2 domain mutant (E457A) mediated basal repression but not derepression, suggesting that interaction with a putative coactivator at this site may be critical for derepression. Interestingly, a mutant containing only the TRβ ligand binding domain (LBD) not only mediated derepression, but also stimulated transcriptional activation 10-fold higher than basal level. Studies using deletion and domain swap mutants localized an inhibitory region to the TRβ DNA-binding domain. Titration studies further suggested that allosteric changes promoting interaction with coactivators may account for enhanced transcriptional activity by LBD. In summary, our findings suggest that TR heterodimer formation with RXR is important for repression and derepression, and coactivator interaction with the AF-2 domain may be needed for derepression in this chimeric system. Additionally, there may be an inhibitory region in the DNA-binding domain, which reduces TR interaction with coactivators, and prevents full-length wild-type TRβ from achieving transcriptional activation above basal level in this chimeric receptor system.