The relationship between anti-mullerian hormone in women receiving fertility assessments and age at menopause in subfertile women : evidence from large population studies

Context: Anti-Müllerian hormone (AMH) concentration reflects ovarian aging and is argued to be a useful predictor of age at menopause (AMP). It is hypothesized that AMH falling below a critical threshold corresponds to follicle depletion, which results in menopause. With this threshold, theoretical predictions of AMP can be made. Comparisons of such predictions with observed AMP from population studies support the role for AMH as a forecaster of menopause. Objective: The objective of the study was to investigate whether previous relationships between AMH and AMP are valid using a much larger data set. Setting: AMH was measured in 27 563 women attending fertility clinics. Study Design: From these data a model of age-related AMH change was constructed using a robust regression analysis. Data on AMP from subfertile women were obtained from the population-based Prospect-European Prospective Investigation into Cancer and Nutrition (Prospect- EPIC) cohort (n � 2249). By constructing a probability distribution of age at which AMH falls below a critical threshold and fitting this to Prospect-EPIC menopausal age data using maximum likelihood, such a threshold was estimated. Main Outcome: The main outcome was conformity between observed and predicted AMP. Results: To get a distribution of AMH-predicted AMP that fit the Prospect-EPIC data, we found the critical AMH threshold should vary among women in such a way that women with low age-specific AMH would have lower thresholds, whereas women with high age-specific AMH would have higher thresholds (mean 0.075 ng/mL; interquartile range 0.038–0.15 ng/mL). Such a varying AMH threshold for menopause is a novel and biologically plausible finding. AMH became undetectable (�0.2 ng/mL) approximately 5 years before the occurrence of menopause, in line with a previous report. Conclusions: The conformity of the observed and predicted distributions of AMP supports the hypothesis that declining population averages of AMH are associated with menopause, making AMH an excellent candidate biomarker for AMP prediction. Further research will help establish the accuracy of AMH levels to predict AMP within individuals.

Decision-making about hormone replacement therapy by women in England and Scotland

OBJECTIVE: The aim of this study was to explore women's decision-making about the balance of risks and benefits of taking hormone replacement therapy (HRT) based on the latest evidence from the Women's Health Initiative (WHI) trial of combined HRT. METHODS: Women aged 50-69 years, who were eligible for the Women's International Study of long Duration Oestrogen after Menopause (WISDOM) trial, were invited to participate in one of eight focus groups. Participants were asked to discuss their views about taking HRT based on the latest international evidence. RESULTS AND CONCLUSIONS: Eighty-two women participated overall. Qualitative content analysis was applied to the discussion transcripts. Women regarded the decisions they make about taking HRT as highly personal, and, for women currently taking HRT, the overwhelming reason for continuation was perceived improvement in quality of life regardless of either the risks or the benefits in the longer term.

The willingness of women to participate in a long-term trial of hormone replacement therapy : A qualitative study using focus groups.

The actual proportion of eligible people who participate in clinical trials is low. Consequently, a qualitative study of the willingness of women who are postmenopausal to participate in a long-term randomized control trial of hormone replacement therapy (HRT) designed to investigate the prevention of degenerative diseases was conducted. Focus group methodology was employed to explore the personal and social aspects of decision making about trial participation. Participants were randomly selected from the patient age-sex registers of four University of Adelaide general practices. Twenty-one women participated in four focus groups. The reasons for and against trial participation were examined using qualitative content analysis; ( n = 18) women were unwilling to participate in the trial. The lack of perceived individual benefit, minimal altruism, the risk of breast cancer and side effects, not wanting to take unnecessary medication, a ten-year commitment, and negative experiences of HRT use, were the main reasons given for not entering the trial. Of the few women ( n = 3) who clearly would enter the trial, free prescriptions and a positive history of using HRT were the main reasons for participation. The perceived disadvantages of clinical trials of HRT deter women from participating in a long-term clinical trial of HRT. An investment in education and information to eligible participants about both the risks and potential benefits of HRT may improve trial recruitment.

Ultra-trace detection of diagnostically important biomarkers using functionalised-Surface Enhanced Raman Spectroscopy (SERS)

Here we report an ultrasensitive method for detecting bio-active compounds in biological samples by means of functionalised nanoparticles interrogated by surface enhanced Raman spectroscopy (SERS). This method is applicable to the recovery and detection of many diagnostically important peptidyl analytes such as insulin, human growth hormone, growth factors (IGFs) and erythropoietin (EPO), as well as many small molecule analytes and metabolites. Our method, developed to detect EPO, demonstrates its utility in a complex yet well defined biological system. Recombinant human EPO (rhEPO) and EPO analogues have successfully been used to treat anaemia in end-stage renal failure, chronic disorders and infections, cancer and AIDS. Current methods for EPO testing are lengthy, laborious and relatively insensitive to low concentrations. In our rapid screening methodology, gold nanoparticles were functionalised with anti-EPO antibodies to provide very high selectivity towards the EPO protein in urine. These “smart sensor” nanoparticles interact with and trap EPO. Subsequent SERS screening allows for the detection and quantisation of ultra trace amounts (<<10-15 M) of EPO in urine samples with minimal sample preparation. We present data showing that the SERS spectrum differentiates between human endogenous EPO and rhEPO in unpurified urine, and potentially distinguishes between purified EPO isoforms. The elimination of sample preparation and direct screening in biological fluids significantly reduces the time required by current methods. Antibody recognition against a variety of biological targets and the availability of portable commercial SERS analysers for rapid onsite testing suggest broad diagnostic applicability in a flexible analytical platform.

Investigation of hormone receptor genes in migraine

Migraine is a common neurological condition with a complex mode of inheritance. Steroid hormones have long been implicated in migraine, although their role remains unclear. Our investigation considered that genes involved in hormonal pathways may play a role in migraine susceptibility. We therefore investigated the androgen receptor (AR) CAG repeat, and the progesterone receptor (PR) PROGINS insert by cross-sectional association analysis. The results showed no association with the AR CAG repeat in our study group of 275 migraineurs and 275 unrelated controls. Results of the PR PROGINS analysis showed a significant difference in the same cohort, and in an independent follow-up study population of 300 migraineurs and 300 unrelated controls. Analysis of the genotypic risk groups of both populations together indicated that individuals who carried the PROGINS insert were 1.8 times more likely to suffer migraine. Interaction analysis of the PROGINS variant with our previously reported associated ESR1 594A variant showed that individuals who possessed at least one copy of both risk alleles were 3.2 times more likely to suffer migraine. Hence, variants of these steroid hormone receptor genes appear to act synergistically to increase the risk of migraine by a factor of three.

Molecular genetic analyses of RFLPs for PCR-amplified growth hormone gene, renal kallikrein gene and atrial natriuretic factor gene in essential hypertension

The present study examined polymorphisms of genes that might be involved in the onset of essential hypertension (HT). These included the (i) growth hormone gene (GH1), whose locus has recently been linked to elevated blood pressure (BP) in the stroke-prone SHR, although recent sib-pair analysis of a polymorphism near the human chorionic somatomammotropin gene (a member of the GH cluster) was unable to show linkage with HT; (ii) renal kallikrein gene (KLK1); and (iii) atrial natriuretic factor gene (ANF), where a primary defect in production or activity of kallikrein or ANF could cause NaCl retention and vasoconstriction. Association analyses were conducted to compare restriction fragment length polymorphisms (RFLPs) of each gene in 85 HT and 95 normotensive (NT) Caucasian subjects whose parents had a similar BP status at age ≥50 years. The frequency of the minor allele of (i) a RsaI RFLP in the promoter of GH1, amplified from leukocyte DNA by the polymerase chain reaction, was 0.15 in the HT group and 0.14 in the NT group (χ1=0.34, P=0.55); (ii) a TaqI RFLP for KLK1 was 0.035 in the HT group and 0.015 in the NT group (χ2=1.5, P=0.21); and (iii) a XhoI RFLP for ANF was 0.50 in HTs and 0.46 in NTs (χ2=0.20, P=0.65). Studies of HT pedigrees found one family in which the ANF locus and HT were not linked, owing to an obligate recombinant. The present data thus provide no evidence for involvement of the growth hormone, renal kallikrein, nor ANF gene in the causation of essential hypertension.

Diurnal rhythm and effects of feeding, exercise and recombinant equine growth hormone on serum insulin concentrations in the horse

Reasons for performing the study As growth hormone increases lean body mass, it could be a therapy for obese horses. However, growth hormone use induces hyperinsulinaemia in some species, so further investigation is warranted. Objectives To investigate the effects of feeding, exercise and growth hormone therapy on basal insulin concentrations in healthy horses. Study design In vivo experimental study. Methods Blood samples were obtained every 30 min from 12 geldings over 24 h, to establish basal serum insulin concentrations, before they underwent a 3-week exercise programme. Horses were allocated into 2 groups and exercised for another 4 weeks. Group A received daily i.m. injections of recombinant equine growth hormone; 5 mg/day for 5 days, then 12.5 mg/day for 16 days. Blood samples were taken daily before feeding. Insulin vs. time area under curve of Groups A and B were compared using a Student's unpaired t test. Results Horses demonstrated insulin peaks within 2 h of feeding of 577 ± 108.3 pmol/l at 09.30 h and 342.4 ± 75.7 pmol/l at 17.30 h, despite receiving the same meal. The nadir was between midnight and 07.30 h. Exercise had no effect on basal insulin concentrations prior to equine growth hormone administrations. The equine growth hormone injections increased serum insulin concentrations (P = 0.01) within Group A, from 44.4 ± 15.3 pmol/l initially to 320.9 ± 238.2 pmol/l by Day 12. Exogenous growth hormone caused variable hyperinsulinaemia, which was alleviated once equine growth hormone administration ceased. Conclusions Single serum samples taken prior to the morning meal provide basal insulin concentrations. Exercise did not change basal insulin concentrations. However, equine growth hormone injections increased basal insulin concentrations, which were not ameliorated by exercise. Potential relevance This therapy is not recommended to address obesity in insulin-resistant equids.

Somatostatin, its receptors and analogs, in lung cancer

Despite developments in diagnosis and treatment, lung cancer is the commonest cause of cancer death in Europe and North America. Due to increasing cigarette consumption, the incidence of the disease and resultant mortality is rising dramatically in women. Novel approaches to the management of lung cancer are urgently required. Somatostatin is a tetradecapeptide first identified in the pituitary and subsequently throughout the body particularly in neuroendocrine cells of the pancreas and gastrointestinal tract and the nervous system. The peptide has numerous functions including inhibition of hormone release, immunomodulation and neurotransmission and is an endogenous inhibitor of cell proliferation and angiogenesis. Somatostatin and its analogs, including octreotide (SMS 201-995), somatuline (BIM 23014) and vapreotide (RC-160), act by binding to specific somatostatin receptors (SSTR) of which there are 5 principal subtypes, SSTR-1-5. Although elevated plasma somatostatin levels may be detected in 14-15% of patients, tumor cell expression appears rare. SSTR may be expressed by lung tumors, particularly small cell lung cancer and bronchial carcinoid disease. [111In]pentetreotide scintigraphy may have a role to play in the localization and staging of lung cancers both before and following treatment, and in detecting relapsed disease. The potential role of radiolabelled somatostatin analogs as radiotherapeutic agents in the management of lung cancer is currently being explored. Somatostatin analog therapy results in significant growth inhibition of both SSTR-positive and SSTR-negative lung tumors in vivo. Recent work indicates that these agents may enhance the efficacy of chemotherapeutic agents in the treatment of solid tumors including lung cancer. Copyright © 2001 S. Karger AG, Basel.

Exenatide extended-release; clinical trials, patient preference, and economic considerations

Type 2 diabetes remains an escalating world-wide problem, despite a range of treatments. The revelation that insulin secretion is under the control of a gut hormone, glucagon-like peptide 1 (GLP-1) led to a new paradigm in the management of type 2 diabetes, medicines that directly stimulate, or that prolong the actions of the endogenous GLP-1, at its receptors. Exenatide is an agonist at the GLP-1 receptors, and was initially developed as a subcutaneous twice daily medication, ExBID. The clinical trials with ExBID established a role for exenatide in the treatment of type 2 diabetes. Subsequently, once weekly exenatide (ExQW) was shown to have advantages over ExBID, and there is now more emphasis on the development of ExQW. ExQW alone reduces glycosylated haemoglobin (HbA1c) and body weight, and is well tolerated. ExQW has been compared to sitagliptin, pioglitazone and metformin, and shown to have a greater ability to reduce HbA1c than these other medicines. The only preparation of insulin, which ExQW has been compared to, is insulin glargine, and the ExQW has some favourable properties in this comparison, notably causing weight loss, compared to the gain with insulin glargine. ExQW has been compared to another GLP-1 receptor agonist, liraglutide, and ExQW is non-inferior to liraglutide in reducing HbA1c. The small amount of evidence available, shows that subjects with type 2 diabetes, prefer ExQW to ExBID, and that adherence was high to these in the clinical trial setting. Healthcare and economic modelling suggests that ExQW will reduce diabetic complications and be cost-effective, compared to other medications, with long term use. Little is known about whether subjects with type 2 diabetes prefer ExQW to other medicines, and whether adherence is good to ExQW in practice, and these important topics require further study.

Efficient silencing of endogenous microRNAs using artificial microRNAs in Arabidopsis thaliana

We report here that the expression of endogenous microRNAs (miRNAs) can be efficiently silenced in Arabidopsis thaliana (Arabidopsis) using artificial miRNA (amiRNA) technology. We demonstrate that an amiRNA designed to target a mature miRNA directs silencing against all miRNA family members, whereas an amiRNA designed to target the stem-loop region of a miRNA precursor transcript directs silencing against only the individual family member targeted. Furthermore, our results indicate that amiRNAs targeting both the mature miRNA and stem-loop sequence direct RNA silencing through cleavage of the miRNA precursor transcript, which presumably occurs in the nucleus of a plant cell during the initial stages of miRNA biogenesis. This suggests that small RNA (sRNA)-guided RNA cleavage in plants occurs not only in the cytoplasm, but also in the nucleus. Many plant miRNA gene families have been identified via sequencing and bioinformatic analysis, but, to date, only a small tranche of these have been functionally characterized due to a lack of effective forward or reverse genetic tools. Our findings therefore provide a new and powerful reverse-genetic tool for the analysis of miRNA function in plants. © The Author 2010. Published by the Molecular Plant Shanghai Editorial Office in association with Oxford University Press on behalf of CSPP and IPPE, SIBS, CAS.

Sex hormone regulation of innate immunity in the female reproductive tract : the role of epithelial cells in balancing reproductive potential with protection against sexually transmitted pathogens

The immune system in the female reproductive tract (FRT) does not mount an attack against HIV or other sexually transmitted infections (STI) with a single endogenously produced microbicide or with a single arm of the immune system. Instead, the body deploys dozens of innate antimicrobials to the secretions of the female reproductive tract. Working together, these antimicrobials along with mucosal antibodies attack many different viral, bacterial and fungal targets. Within the FRT, the unique challenges of protection against sexually transmitted pathogens coupled with the need to sustain the development of an allogeneic fetus have evolved in such a way that sex hormones precisely regulate immune function to accomplish both tasks. The studies presented in this review demonstrate that estradiol and progesterone secreted during the menstrual cycle act both directly and indirectly on epithelial cells and other immune cells in the reproductive tract to modify immune function in a way that is unique to specific sites throughout the FRT. As presented in this review, studies from our laboratory and others demonstrate that the innate immune response is under hormonal control, varies with the stage of the menstrual cycle, and as such is suppressed at mid-cycle to optimize conditions for successful fertilization and pregnancy. In doing so, a window of STI vulnerability is created during which potential pathogens including HIV enter the reproductive tract to infect host targets.

Validation of β-actin used as endogenous control for gene expression analysis in mechanobiology studies : amendments

We write in response to the letter by Liu et al. [1] commenting on our article, ‘‘Mesenchymal Stem Cells Regulate Angiogenesis According to Their Mechanical Environment’’ [2]. The study by Liu et al. demonstrates that the commonly used endogeneous reference gene (ERG), b-actin, is upregulated by mechanical loading, indicating a potential bias in the determined target gene expression when normalizing to b-actin, such as in our report on unchanged vascular endothelial growth factor (VEGF) and hypoxia-inducible factors (HIF)-1a mRNA levels in mechanically loaded mesenchymal stem cells (MSCs).

Identification of a long non-coding RNA gene, GHSROS (growth hormone secretagogue receptor opposite strand), which stimulates cell migration in non-small cell lung cancer cell lines

The molecular mechanisms involved in non‑small cell lung cancer tumourigenesis are largely unknown; however, recent studies have suggested that long non-coding RNAs (lncRNAs) are likely to play a role. In this study, we used public databases to identify an mRNA-like, candidate long non-coding RNA, GHSROS (GHSR opposite strand), transcribed from the antisense strand of the ghrelin receptor gene, growth hormone secretagogue receptor (GHSR). Quantitative real-time RT-PCR revealed higher expression of GHSROS in lung cancer tissue compared to adjacent, non-tumour lung tissue. In common with many long non-coding RNAs, GHSROS is 5' capped and 3' polyadenylated (mRNA-like), lacks an extensive open reading frame and harbours a transposable element. Engineered overexpression of GHSROS stimulated cell migration in the A549 and NCI-H1299 non-small cell lung cancer cell lines, but suppressed cell migration in the Beas-2B normal lung-derived bronchoepithelial cell line. This suggests that GHSROS function may be dependent on the oncogenic context. The identification of GHSROS, which is expressed in lung cancer and stimulates cell migration in lung cancer cell lines, contributes to the growing number of non-coding RNAs that play a role in the regulation of tumourigenesis and metastatic cancer progression.

Tandem mass spectrometry of deprotonated iodothyronines

In order to assist with the development of more selective and sensitive methods for thyroid hormone analysis the \[M-H](-) anions of the iodothyronines T4, T3, rT3, (3,5)-T2 and the non-iodinated thyronine (TO) have been generated by negative ion electrospray mass spectrometry. Tandem mass spectra of these ions were recorded on a triple-quadrupole mass spectrometer and show a strong analogy with the fragmentation pathways of the parent compound, tyrosine. All iodothyronines also show significant abundances of the iodide anion in their tandem mass spectra, which represents an attractive target for multiple reaction monitoring (MRM) analysis, given that iodothyronines are the only iodine bearing endogenous molecules. Characteristic fragments are observed at m/z 359.7 and 604.5 for rT3 but are absent in the spectrum of T3, thus differentiating the two positional isomers. The striking difference in the fragmentation patterns of these regioisomeric species is attributed to the increased acidity of the phenol moiety in rT3 compared with T3. Copyright (C) 2005 John Wiley & Sons, Ltd.

Intermittent Fugu parathyroid hormone 1 (1–34) is an anabolic bone agent in young male rats and osteopenic ovariectomized rats

Human parathyroid hormone (hPTH) is currently the only treatment for osteoporosis that forms new bone. Previously we described a fish equivalent, Fugu parathyroid hormone 1 (fPth1) which has hPTH-like biological activity in vitro despite fPth1(1–34) sharing only 53% identity with hPTH(1–34). Here we demonstrate the in vivo actions of fPth1(1–34) on bone. In study 1, young male rats were injected intermittently for 30 days with fPth1 [30 μg–1000 μg/kg body weight (b.w.), (30fPth1–1000fPth1)] or hPTH [30 μg–100 μg/kg b.w. (30hPTH–100hPTH)]. In proximal tibiae at low doses, the fPth1 was positively correlated with trabecular bone volume/total volume (TbBV/TV) while hPTH increased TbBV/TV, trabecular thickness (TbTh) and trabecular number (TbN). 500fPth1 and 1000fPth1 increased TbBV/TV, TbTh, TbN, mineral apposition rate (MAR) and bone formation rate/bone surface (BFR/BS) with a concomitant decrease in osteoclast surface and number. In study 2 ovariectomized (OVX), osteopenic rats and sham operated (SHAM) rats were injected intermittently with 500 μg/kg b.w. of fPth1 (500fPth1) for 11 weeks. 500fPth1 treatment resulted in increased TbBV/TV (151%) and TbTh (96%) in the proximal tibiae due to increased bone formation as assessed by BFR/BS (490%) and MAR (131%). The effect was restoration of TbBV/TV to SHAM levels without any effect on bone resorption. 500fPth1 also increased TbBV/TV and TbTh in the vertebrae (L6) and cortical thickness in the mid-femora increasing bone strength at these sites. fPth1 was similarly effective in SHAM rats. Notwithstanding the low amino acid sequence homology with hPTH (1–34), we have clearly established the efficacy of fPth1 (1–34) as an anabolic bone agent.