Lineage-Specific Restraint of Pituitary Gonadotroph Cell Adenoma Growth

Although pituitary adenomas are usually benign, unique trophic mechanisms restraining cell proliferation are unclear. As GH-secreting adenomas are associated with p53/p21-dependent senescence, we tested mechanisms constraining non-functioning pituitary adenoma growth. Thirty six gonadotroph-derived non-functioning pituitary adenomas all exhibited DNA damage, but undetectable p21 expression. However, these adenomas all expressed p16, and >90% abundantly expressed cytoplasmic clusterin associated with induction of the Cdk inhibitor p15 in 70% of gonadotroph and in 26% of somatotroph lineage adenomas (p = 0.006). Murine LβT2 and αT3 gonadotroph pituitary cells, and αGSU.PTTG transgenic mice with targeted gonadotroph cell adenomas also abundantly expressed clusterin and exhibited features of oncogene-induced senescence as evidenced by C/EBPβ and C/EBPδ induction. In turn, C/EBPs activated the clusterin promoter ∼5 fold, and elevated clusterin subsequently elicited p15 and p16 expression, acting to arrest murine gonadotroph cell proliferation. In contrast, specific clusterin suppression by RNAis enhanced gonadotroph proliferation. FOXL2, a tissue-specific gonadotroph lineage factor, also induced the clusterin promoter ∼3 fold in αT3 pituitary cells. As nine of 12 pituitary carcinomas were devoid of clusterin expression, this protein may limit proliferation of benign adenomatous pituitary cells. These results point to lineage-specific pathways restricting uncontrolled murine and human pituitary gonadotroph adenoma cell growth

Oral Glucose Tolerance Test Performed after 28 Gestational Weeks and Risk for Future Diabetes—A 5-Year Cohort Study

Gestational diabetes mellitus (GDM) is diagnosed by an oral glucose tolerance test (oGTT), preferably performed at 24 + 0–28 + 6 gestational weeks, and is considered a risk factor for type 2 diabetes (T2DM). In this study, we aimed to evaluate the risk of T2DM associated with abnormal oGTT performed after 28 weeks. We conducted a retrospective cohort study that included parturients with available glucose levels during pregnancy and up to 5 years of follow-up after pregnancy. Data were extracted from the computerized laboratory system of Meuhedet HMO and cross-tabulated with the Israeli National Registry of Diabetes (INRD). The women were stratified into two groups: late oGTT (performed after 28 + 6 weeks) and on-time oGTT (performed at 24 + 0–28 + 6 weeks). The incidence of T2DM was evaluated and compared using univariate analysis followed by survival analysis adjusted to confounders. Overall, 78,326 parturients entered the analysis. Of them, 6195 (7.9%) performed on-time oGTT and 5288 (6.8%) performed late oGTT. The rest—66,846 (85.3%)—had normal glucose tolerance. Women who performed late oGTT had lower rates of GDM and T2DM. However, once GDM was diagnosed, regardless of oGTT timing, the risk of T2DM was increased (2.93 (1.69–5.1) vs. 3.64 (2.44–5.44), aHR (95% CI), late vs. on-time oGTT, p < 0.001 for both). Unlike in oGTT performed on time, one single abnormal value in late oGTT was not associated with an increased risk for T2DM

Foetal Sonographic Anogenital Distance Is Longer in Polycystic Ovary Syndrome Mothers

Anogenital distance (AGD) is a biomarker for the prenatal hormonal environment. Androgen excess is a key element in polycystic ovary syndrome (PCOS). The aim of this study was to assess the sonographic foetal AGD in a population of PCOS mothers in comparison to the general population. Foetal AGD was measured prospectively by 2D ultrasound in PCOS mothers and compared to prenatal AGD nomograms. The results were interpreted regarding maternal and foetal characteristics. The mean sonographic foetal AGD centile measurement in PCOS mothers was significantly longer in comparison to the general population (86.04% &plusmn; 18.22; p &lt; 0.001). Estimated foetal weight and birthweight were appropriate for gestational age and did not correlate with AGD. Sonographic foetal AGD was significantly longer in PCOS diabetic mothers and in those who conceived following assisted reproduction treatments when compared to the general population (p &lt; 0.001). Our results support the role of AGD as a biomarker of the prenatal hormonal environment and provide evidence for the hyperandrogenic effect in PCOS pregnancies on foetal androgenic status and genitalia development

Dynamics of thyroid diseases and thyroid‐axis gland masses

Abstract Thyroid disorders are common and often require lifelong hormone replacement. Treating thyroid disorders involves a fascinating and troublesome delay, in which it takes many weeks for serum thyroid‐stimulating hormone (TSH) concentration to normalize after thyroid hormones return to normal. This delay challenges attempts to stabilize thyroid hormones in millions of patients. Despite its importance, the physiological mechanism for the delay is unclear. Here, we present data on hormone delays from Israeli medical records spanning 46 million life‐years and develop a mathematical model for dynamic compensation in the thyroid axis, which explains the delays. The delays are due to a feedback mechanism in which peripheral thyroid hormones and TSH control the growth of the thyroid and pituitary glands; enlarged or atrophied glands take many weeks to recover upon treatment due to the slow turnover of the tissues. The model explains why thyroid disorders such as Hashimoto's thyroiditis and Graves' disease have both subclinical and clinical states and explains the complex inverse relation between TSH and thyroid hormones. The present model may guide approaches to dynamically adjust the treatment of thyroid disorders

Hypoglycaemia and its management in primary care setting

Abstract Hypoglycemia is common in patients with type 1 diabetes (T1D) and type 2 diabetes (T2D) and constitutes a major limiting factor in achieving glycemic control among people with diabetes. While hypoglycemia is defined as a blood glucose level under 70 mg/dL (3.9?mmol/L), symptoms may occur at higher blood glucose levels in individuals with poor glycemic control. Severe hypoglycemia is defined as an episode requiring the assistance of another person to actively administer carbohydrate, glucagon, or take other corrective actions to assure neurologic recovery. Hypoglycemia is the most important safety outcome in clinical studies of glucose lowering agents. The ADA Standards of Medical Care recommends that a management protocol for hypoglycemia should be designed and implemented by every hospital, along with a clear prevention and treatment plan. A tailored approach, using clinical and pathophysiologic disease stratification, can help individualize glycemic goals and promote new therapies to improve quality of life of patients. Data from recent large clinical trials reported low risk of hypoglycemic events with the use of newer antidiabetic drugs. Increased hypoglycemia risk is observed with the use of insulin and/or sulfonylureas. Vulnerable patients with T2D at dual risk of severe hypoglycemia and Cardiovascular (CV) outcomes show features of ?frailty?. Many of such patients may be better treated by the use of GLP-1 receptor agonists or SGLT2 inhibitors rather than insulin. CGM should be considered for all individuals with increased risk for hypoglycemia, impaired hypoglycemia awareness, frequent nocturnal hypoglycemia and with history of severe hypoglycemia. Patients with impaired awareness of hypoglycemia (IAH) benefit from real-time continuous glucose monitoring (CGM). The diabetes educator is an invaluable resource and can devote the time needed to thoroughly educate the individual to reduce the risk of hypoglycemia and integrate the information within the entire construct of diabetes self-management. Conversations about hypoglycemia facilitated by a healthcare professional may reduce the burden and fear of hypoglycemia among patients with diabetes and their family members. Optimizing insulin doses and carbohydrate intake, in addition to a short warm up before or after the physical activity sessions may help avoiding hypoglycemia. Several therapeutic considerations are important to reduce hypoglycemia risk during pregnancy including administration of rapid-acting insulin analogs rather than human insulin, pre-conception initiation of insulin analogs, and immediate postpartum insulin dose reduction. This article is protected by copyright. All rights reserved.Peer reviewe

Admission blood glucose and 10-year mortality among patients with or without pre-existing diabetes mellitus hospitalized with heart failure

Abstract Background High admission blood glucose (ABG) level has been associated with a poor short-term outcome among non-diabetic patients with heart failure (HF). We aimed to investigate the association between ABG levels and long-term (10 years) mortality in patients with or without pre-existing diabetes mellitus (DM) admitted with HF. Methods We analyzed data on 1811 patients with DM and 2182 patients without pre-existing DM who were hospitalized with HF during a prospective national survey. The relationship between ABG and 10-year mortality was assessed using the Cox proportional hazard model adjusting for multiple variables. ABG was analyzed both as a categorical (200 mg/dL) and as a continuous variable. Results At 10 years of follow-up the cumulative probability of mortality was 85 and 78% among patients with DM and patients with no pre-existing DM (p 200 mg/dL had an increased mortality risk (>200 mg/dL versus 200 mg/dL is associated with increased mortality risk

FOXL2 stimulates the clusterin promoter.

<p><b>A</b>) Effects of FOXL2 on the clusterin promoter in αT3 cells 24 h after transfection. Cells were co-transfected with 200 ng murine pGL3-luc-m<i>Clu</i> reporter plasmid and indicated amounts of pcDNA3-His-mFoxl2. The ratio of luciferase to co-trasfected β-galactosidase control reporter vector was normalized to pCDNA3-null expression vector. SEM was calculated from triplicate assays, and experiments repeated three times with similar results. Results of a representative experiment are shown; **,p<0.01; <b>B</b>) Western blot analysis of clusterin expression in αT3 cells 24 hours after transfection with pcDNA3-His-mFoxl2; <b>C</b>) ChiP assay was performed in nuclear fractions derived from αT3 cell lysates. Top, schematic of the approximate location of primers used in the PCR reactions. Enrichment of specific clusterin promoter sequences was obtained with primer Set 2. FOXL2, specific antibody, IgG, nonspecific antibody, PCP, positive control primers. The experiment was repeated twice, and results of a representative assay shown.</p

C/EBPs induce clusterin.

<p><b>A</b>) C/EBPβ is up-regulated in the αGSU.<i>PTTG</i> pituitary. Confocal image showing C/EBPβ co-localization with αGSU-positive, GH-positive and PRL-positive cells in WT and pre-tumorous αGSU.<i>PTTG</i> pituitary glands. (Hormones-green, cytoplsmic, C/EBPβ–red, intranuclear); <b>B</b>) Western blot analysis of C/EBPβ and δ isoforms induced in LβT2 cells stably transfected with m<i>Pttg</i>; <b>C</b>) Effects of C/EBPs on the clusterin promoter in LβT2 and αT3 cells 24 h after transfection. Cells were co-transfected with 200 ng murine pGL3-luc-m<i>Clu</i> reporter plasmid and 800 ng murine pCDNA3-C/EBPα, β or δ. The ratio of luciferase to co-trasfected β-galactosidase control reporter vector was normalized to pCDNA3-null expression vector. SEM was calculated from triplicate assays, and experiments repeated three times with similar results. Results of a representative experiment are shown.*, p<0.05, **,p<0.01; <b>D</b>) Western blot analysis of clusterin expression in gonadotroph-derived αT3 cells 24 hours after transfection with pCDNA3-C/EBPβ or <b>E</b>) pCDNA3-C/EBPδ; <b>F</b>) Western blot analysis of clusterin expression in LβT2 mPttg cells 48 hours after simultaneous transfection with siC/EBPβ and siC/EBPδ (3 nM each). Two different combinations of siRNAs were used.</p

Clusterin restrains pituitary cell proliferation by inducing Cdk inhibitors.

<p>Western blot analysis of Cdk inhibitors and proliferation markers <b>A</b>) in LβT2 cells, <b>B</b>) in αT3 cells 48 h after transfection with m<i>Clu</i>; <b>C</b>) Confocal images of immunofluoprescence of histone H3 methylation on lysine 9 (H3-K9M) (red) in vector and <i>Clu</i>-expressing αT3 cells 48 hours after transfection; <b>D</b>) Quantification of positive H3-K9M foci. Cells were fixed, stained with H3-K9M antibody, and one thousand cells/field counted in three randomly chosen visual fields; <b>E</b>) Percentage of BrdU positive cells 48 h after transfection with m<i>Clu</i>. Triplicate samples were pulsed with BrdU for 30 min and analyzed by flow cytometry, *, p<0.05; <b>F</b>) αT3 cells stably overexpressing <i>mClu</i> or vector were synchronized in 0.1% fetal bovine serum for 18 hours, and then cultured in 10% fetal bovine serum. At the indicated times, duplicate samples were pulsed with BrdU for 30 min, analyzed by flow cytometry, and cells in S-phase identified by staining with BrdU antibodies.</p