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Medicine by Alexandros G. Sfakianakis,Anapafseos 5 Agios Nikolaos 72100 Crete Greece,00302841026182,00306932607174,alsfakia@gmail.com,
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Publication date: December 2017
Source:European Journal of Cancer, Volume 87
Author(s): R.A. Anderson, J. Mansi, R.E. Coleman, D.J.A. Adamson, R.C.F. Leonard
AimChemotherapy results in permanent loss of ovarian function in some premenopausal women. Accurate identification in women with hormone-sensitive early breast cancer (eBC) would allow optimisation of subsequent endocrine treatment. We sought to assess whether analysis of anti-Müllerian hormone (AMH) using a sensitive automated assay could identify women who would not regain ovarian function after chemotherapy.MethodsData from women in the Ovarian Protection Trial in Premenopausal Breast Cancer Patients (OPTION) trial of goserelin (a gonadotrophin-releasing hormone (GnRH) analogue) for ovarian protection were analysed. Women were assessed for premature ovarian insufficiency (POI: amenorrhoea with elevated follicle-stimulating hormone (FSH)) at 24 months after diagnosis. The accuracy of AMH for the diagnosis of POI and its prediction from measurement at the end of chemotherapy was calculated.ResultsAMH below the level of detection showed good diagnostic accuracy for POI at 24 months (n = 73) with receiver operating characteristic (ROC) area under the curve of 0.86, sensitivity 1.0 and specificity 0.73 at the assay limit of detection. In women aged >40 at diagnosis who did not receive goserelin, AMH measured at end of chemotherapy also gave good prediction of POI at 24 months (area under the curve (AUC) 0.89 95% CI 0.75–1.0, n = 32), with sensitivity 0.91, specificity 0.82, diagnostic odds ratio (DOR) 42.8. FSH gave slightly lower AUC, and specificity was low at 0.55. Age but not tamoxifen impacted on AMH levels.ConclusionUsing this sensitive AMH assay, the finding of an undetectable AMH level in women aged >40 at the end of chemotherapy for eBC gave a good prediction that ovarian function would not return. This may allow alterations in post-chemotherapy endocrine management.
http://ift.tt/2yyW5Vc
Publication date: November 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology, Volume 174
Author(s): Annekathrin M. Keiler, Dana Macejova, Birgit M. Dietz, Judy L. Bolton, Guido F. Pauli, Shao-Nong Chen, Richard B. van Breemen, Dejan Nikolic, Florian Goerl, Michael H. Muders, Oliver Zierau, Günter Vollmer
Supplements with estrogenic activities are intensively investigated as potential alternatives for the treatment of menopausal symptoms. These investigations include studies on their safety regarding potential breast cancer risks. Therefore, the aim of this study was to assess whether or not a standardized hops (Humulus lupulus) extract, containing 0.42% of the estrogenic flavanone, 8-prenylnaringenin, would stimulate growth of methyl-nitrosourea (MNU) induced mammary cancer in ovariectomized (OVX) Sprague-Dawley (SD) rats or would impact on the proliferative activity within the normal mammary gland of Wistar rats. To induce tumorigenesis SD-rats received an intraperitoneal injection of 50mg/kg body weight of MNU on postnatal days PND 50 and 52. 28days later animals were OVX or were SHAM operated (positive control) and randomly allocated and maintained for 140days on either a phytoestrogen-free placebo diet (SHAM and negative control) or on the hops fortified diet. For the investigations in the normal mammary gland young adult Wistar rats were bilaterally OVX and randomly allocated to a control group fed to a phytoestrogen-free diet, or to a diet supplemented either with E2-benzoate or the hops extract. As a major result, the tumor incidence was 15% (3 tumors totally) in OVX controls, whereas it was 85% (39 tumors totally) in SHAM operated positive controls. No tumors were detectable in the hops group. In addition, no estrogenic activity of the hops extract was detectable in uterus and liver of these animals. In investigations on the normal mammary gland, no impact of hops extract on the expression of estrogen dependent proliferation markers or of progesterone receptor became apparent. In conclusion, the lack of growth stimulation of MNU-induced breast cancer in OVX SD-rats and the lack of stimulation proliferative events in the normal mammary gland of OVX Wistar rats by standardized hops extracts provides an important piece of evidence regarding the safety of these extracts in the management of menopausal symptoms.
http://ift.tt/2h8Us5e
Publication date: Available online 26 October 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Angeles C. Tecalco-Cruz
Nuclear receptors (NRs) are transcription regulators that direct the expression of many genes linked to cellular processes, such as proliferation, differentiation, and apoptosis. Additionally, some cellular events are also modulated by signaling pathways induced by NRs outside of the nucleus. Hence, the subcellular transport of NRs is dynamic and is modulated by several signals, protein-protein interaction, and posttranslational modifications. Particularly, the exit of NRs from the nucleus to cytoplasm and/or other compartments is transcendental, as it is this export event, which determines their abundance in the cells' compartments, the activation or attenuation of nuclear or extranuclear pathways, and the magnitude and duration of their effects inside or outside of the nucleus. Consequently, an adequate control of the distribution of NRs is critical for homeostasis, because a deregulation in the nucleo-cytoplasmic transport of NRs could be involved in diseases including cancer as well as metabolic and vascular alterations. In this review, we investigated the pathways and molecular and biological aspects that have been described for the nuclear export of NRs so far and their functional relevance in some diseases. This information suggests that the transport of NRs out of the nucleus is a key mechanism for the identification of new therapeutic targets for alterations associated with the deregulation of the function of NRs.
http://ift.tt/2iz5h0S
Publication date: Available online 2 November 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Vinod Yalamanchili, J. Christopher Gallagher
Depression is a common problem affecting millions, usually treated with selective serotonin uptake inhibitors. Interest in vitamin D as a co-therapy was stimulated by some association studies that correlated depression with low serum 25OHD levels. There are few longitudinal studies of vitamin D and depression and most are single doses of vitamin D. In this study we examined the effect of one-year treatment with several doses of vitamin D on the Geriatric depression score (GDS) in older Caucasian and African American women. The clinical trial was a study of seven daily oral doses of vitamin D (400-4800IU/d) in Black and White older women. The trial was a double blind, randomized and placebo controlled lasting 12-months. The main inclusion criterion was serum 25 hydroxyvitamin D (25OHD) ≤ 20ng/ml (50nmo/L). Calcium supplements were given to maintain calcium intake 1000mg in young people and 1200–1400mg/day in older women. Data on Geriatric depression (GDS) was collected using the validated long form at baseline and 12-months. The change in serum 25OHD was the primary outcome and GDS was one of the secondary outcomes. Adjustments were made for relevant covariates. Analysis of vitamin D effect was by dose low, medium and high compared to placebo or by quintiles. Serum 25OHD increased as a quadratic curve function to a mean of 46ng/ml (115nmol/l) in white women and 49ng/ml (122.5nmol/L) in black women on the highest dose of 4800 IU. In older women mean GDS scores changed from 3.8 (SD±4.2) at baseline to 3.6 (SD±4.1) at 12 months in whites and from 3.0 (SD±3.7) to 3.02 (SD±4.2) in Blacks. (p=0.790 in whites; p=0.958 in blacks). After 12-months there was no effect of dose on change in GDS score in women treated with different doses of vitamin D (p=0.507 in whites and p=0.340 in blacks). When both Caucasians and African Americans were divided into 3 dose groups, low (400-800 IU), medium (1600-3200 IU) and high (4000-4800 IU) doses, the change in score was 0.8 on low dose, −0.30 on medium dose and −0.31 on high dose compared to 0.11 on placebo (p=0.546). In summary, there was no improvement in GDS scores in Caucasians or African Americans on either increasing doses of vitamin D or quintiles of achieved response in serum 25OHD. The changes were small and not significant perhaps because of the relatively lower numbers of depressed women in the groups. Further studies should recruit larger numbers, 3 dose groups covering a serum25OHD range of 20–60ng/ml and more subjects with clinical depression in order to fully address the question of vitamin D effects on depression.
http://ift.tt/2h9t0ob
Publication date: November 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology, Volume 174
Author(s): Valentin Trujillo, Paulina Marín-Luevano, Irma González-Curiel, Adrián Rodríguez-Carlos, Maira Ramírez-Reyes, Esther Layseca-Espinosa, José A. Enciso-Moreno, Lorenza Díaz, Bruno Rivas-Santiago
Foot ulceration is one of the most common and complex sequelae of diabetes mellitus, generally posing a therapeutic challenge due to poor healing responses and high rates of complications, including peripheral vascular disease, ischemia and infections. Calcitriol, the most active vitamin D metabolite, induces antimicrobial peptides production in keratinocytes from diabetic foot ulcers (DFU); however, little is known about its effects on angiogenic factors in this pathology. Herein we aimed at studying whether calcitriol induces angiogenic molecules in keratinocytes under normoxic and hypoxic conditions, and if these molecules are able to improve cell migration in vitro. Evaluation of DFU samples by immunohistochemistry showed increased VEGF and decreased angiogenin and HIF-1α expression compared to controls, suggesting an altered pattern of angiogenic factors in DFU. Interestingly, incubation of keratinocytes with calcitriol significantly upregulated VEGFA, HIF-1α and angiogenin gene expression, while the resulting cell culture media stimulated both endothelial cells and keratinocytes migration in an in vitro wound closure assay under a normoxic environment (p<0.05). Moreover, the culture media of calcitriol-treated keratinocytes stimulated cell migration in a similar extent as exogenous VEGF or EGF in endothelial and keratinocytes cells. These results suggest that the altered profile of angiogenic molecules in DFU might be improved by local or systemic treatment with calcitriol under normoxic conditions, which could probably be achieved with hyperbaric oxygen therapy. Given that calcitriol not only augments proangiogenic factors but also induces antimicrobial peptides expression, this hormone should be further investigated in clinical trials of DFU.
http://ift.tt/2iya42E
Publication date: November 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology, Volume 174
http://ift.tt/2h8C7Wc
Publication date: Available online 1 November 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): María Julia Ferronato, Eliana Noelia Alonso, Débora Gisele Salomón, María Eugenia Fermento, Norberto Ariel Gandini, Mario Alfredo Quevedo, Evangelina Mascaró, Cristian Vitale, Yagamare Fall, María Marta Facchinetti, Alejandro Carlos Curino
Glioblastoma multiforme (GBM) is the worst and most common brain tumor, characterized by high proliferation and invasion rates. The current standard treatment is mainly based on chemoradiotherapy and this approach has slightly improved patient survival. Thus, novel strategies aimed at prolonging the survival and ensuring a better quality of life are necessary. In the present work, we investigated the antitumoral effect of the novel analogue of calcitriol EM1 on GBM cells employing in vitro, in silico, and in vivo assays. In vitro, we demonstrated that EM1 treatment selectively decreases the viability of murine and human tumor cells without affecting that of normal human astrocytes. The analysis of the mechanisms showed that EM1 produces cell cycle arrest in the T98G cell line, which is accompanied by an increase in p21, p27, p57 protein levels and a decrease in cyclin D1, p-Akt-S473, p-ERK1/2 and c-Jun expression. Moreover, EM1 treatment also exerts in GBM cells anti-migratory effects and decreases their invasive capacity by a reduction in MMP-9 proteolytic activity. In silico, we demonstrated that EM1 is able to bind to the vitamin D receptor with greater affinity than calcitriol. Finally, we showed that EM1 treatment of nude mice administered at 50 ug/kg body weight during 21days neither induces hypercalcemia nor toxicity effects. In conclusion, all the results indicate the potential of EM1 analogue as a promising therapeutic alternative for GBM treatment.
Publication date: Available online 4 November 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Mercedes Perusquía, Andrea E. Hanson, Claudia M. Meza, Cris Kubli, Nieves Herrera, John N. Stallone
Dehydroepiandrosterone (DHEA), testosterone (TES) and its 5-reduced metabolites induce a nongenomic vasorelaxation in several vascular beds of mammals; similarly these hormones produce systemic hypotensive and antihypertensive responses in normotensive and hypertensive male rats. Thus, it was hypothesized that the antihypertensive response of androgens, whose levels are elevated during gestation, protect against gestational hypertension. An animal model of preeclampsia was induced in female Wistar rats using DOCA-salt-treated pregnant (PT) and normal pregnant (NP) rats. In vivo experiments in conscious rats revealed that bolus intravenous injections of DHEA, TES, 5α- or 5β-dihydrotestosterone (-DHT) log −1.0 to 2.0μmolk−1min−1, produced substantial transient reductions in arterial blood pressure (BP), without significant changes in heart rate (HR). Mean arterial blood pressure (MAP) was reduced significantly in both groups. PT rats were more sensitive to the antihypertensive responses of androgens than NP. DHEA and 5β-DHT were the most potent to reduce MAP: 66±07 and 69±2.0mmHg in PT but only 33±0.5 and 35±1.2mmHg in NP rats, respectively. In isolated aortas of PT and NP, the concentration-response curves to each androgen (0.1–100μM) indicated that KCl-induced pre-contraction is more sensitive to all androgens than phenylephrine (Phe) pre-contractions. Notably, 5β-DHT is the greatest vasorelaxant with KCl-induced contraction than with Phe contraction of both groups, suggesting a preferential blockade on L-VOCCs. TES exhibited minor vasorelaxing effect of aortas pre-contracted with KCl, compared to its precursor DHEA and its 5-reduced metabolites. These data show that these androgens exert acute vasorelaxing effects in vitro and remarkably, reduce the BP in vivo in PT and NP at term pregnancy. Moreover, a deficit in feto-placental androgen production during pregnancy may trigger the development of preeclampsia or gestational hypertension.
http://ift.tt/2iyjNpF
Publication date: November 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology, Volume 174
Author(s): Ali S. Alzahrani, Meshael M. Alswailem, Avaniyapuram Kannan Murugan, Doha S. Alhomaidah, Cameron P. Capper, Richard J. Auchus, Ebtesam Qasem, Ohoud S. Alzahrani, Afaf Al-Sagheir, Bassam Bin-Abbas
Despite ethnic variation, 11 β-hydroxylase deficiency (11β-OHD) has generally been considered the second most common subtype of congenital adrenal hyperplasia (CAH). We report a high rate of novel mutations in this gene (CYP11B1) in patients from Saudi Arabia. We studied 16 patients with 11β-OHD from 8 unrelated families. DNA was isolated from peripheral blood. The 9 exons and exon-intron boundaries of CYP11B1 were PCR-amplified and directly sequenced. The novel mutations were functionally characterized using subcloning, in vitro mutagenesis, cell transfection and 11-deoxycortisol: cortisol conversion assays. Six mutations were found in these 8 unrelated families. Three of these mutations are completely novel and two have just been recently described as novel mutations from the same population. These include a single nucleotide insertion mutation in codon 18 (c.53_54insT) leading to frameshift and truncation in 4 siblings, a novel mutation (c.1343G>C, p.R448P) in 3 unrelated families, a novel mutation (c.1394A>T, p.H465L) in 2 siblings, a novel mutation (c.617G>T, p.G206V) in 1 patient, and a recently described non-sense novel mutation (c.780G>A, p.W260X) in another patient. Out of the 6 mutations described in this report, only one mutation (p.Q356X) was reported previously. In vitro functional testing of the 3 missense and nonsense novel mutations revealed complete loss of the 11 hydroxylase activity. We conclude that 11 β-OHD in Saudi Arabia has a unique genotype with a high rate of novel mutations. The novel p. R448P mutation is the most common mutation in this highly inbred population.
http://ift.tt/2h71Jmf
Publication date: Available online 29 October 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Yannick Audet-Delage, Jean Grégoire, Patrick Caron, Véronique Turcotte, Marie Plante, Pierre Ayotte, David Simonyan, Lyne Villeneuve, Chantal Guillemette
Endometrial cancer (EC) is the most common gynecologic malignancy prevailing after menopause. Defining steroid profiles may help predict the risk of recurrence after hysterectomy, which remains limited due to the lack of reliable markers. Adrenal precursors, androgens, parent estrogens and catechol estrogen metabolites were measured by mass spectrometry (MS) in preoperative serums and those collected one month after hysterectomy from 246 newly diagnosed postmenopausal EC cases. We also examined the associations between steroid hormones and EC status by including 110 healthy postmenopausal women. Steroid concentrations were analyzed in relation to clinicopathological features, recurrence and overall survival (OS). The mean follow-up time was 65.5 months and 26 patients experienced relapse after surgery for a recurrence incidence of 10.6% (6.4% Type I and 29.5% Type II). Recurrence and OS were related to a more aggressive disease but not linked to body mass index. Preoperative levels of estriol (E3) and estrone-sulfate (E1-S) were inversely associated with recurrence in a multivariate logistic regression analysis (Hazard ratios (HRs) of 0.31, P=0.039 and 3.01, P=0.024; respectively). All circulating steroids declined considerably after surgery almost reaching those of healthy women, except 4-methoxy-E2 (4MeO-E2) for which postoperative levels increased by 35% and were associated to a 68% decreased risk of recurrence (HR=0.32, P=0.015). Women diagnosed with both histological types of EC present significantly higher levels of steroids, in support of their mitogenic effects. The estrogen precursor E1-S, the anticancer metabolite 4MeO-E2, and E3 that exert mixed antagonist and agonist estrogenic activities and immunological effects, are potential independent prognostic factors.
http://ift.tt/2iyjriM
Publication date: Available online 26 October 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Tamar I. Schwarz, Ioanna Katsiadaki, Benjamin H. Maskrey, Alexander P. Scott
Previous studies have shown that mussels can pick up 17β-estradiol [E2] and testosterone [T] from water, metabolize them and conjugate them to fatty acids (esterification), leading to their accumulation in tissue. A key requirement for the esterification process is that a steroid must have a 'reactive' hydroxyl group to conjugate to a fatty acid (which in T, and probably E2, is the β-hydroxyl group on carbon 17). Progesterone (P) lacks any hydroxyl groups and theoretically cannot be esterified and hence should not accumulate in mussels in the same way as E2 or T. However, it is already known that mussels have an enzyme that can achieve 5α-reduction of the A ring of T and P and that there is also another reductase that can transform the 3-oxo group of the 5α-reduced A ring of T into a hydroxyl group. We hypothesized that, although intact P cannot be directly esterified, it might nevertheless be transformed into metabolites that can. To test this hypothesis, we investigated the rate and capacity of uptake, metabolism and potential depuration of tritiated P by the common mussel, Mytilus spp. We found that tritiated P was taken up from water at a similar rate to E2 and T (mean clearance rate 49mL−1 animal−1h−1) and that, as found with the other steroids, the rate of uptake could not be saturated by the addition of non-radioactive steroid (even at 7.6μgL−1). We found that up to 66% of the radioactivity that was taken up was present in the ester fraction, suggesting that hydroxylation of the P must indeed have occurred. We then definitively identified two metabolites in the ester fraction: 5α-pregnane-3β,20β-diol and 3β-hydroxy-5α-pregnan-20-one. These same two steroids were also present in the free steroid fraction. Intact P was not detected in either of the fractions. When undergoing depuration (under semi-static conditions), the radioactivity in the ester fraction remained at the same concentrations in the animals for at least 10 days. Our findings suggest that the lack of reactive hydroxyl groups on P does not preclude it from being taken up, metabolized and subsequently stored. Many questions remain, not least of which is why, when P seems to be so rapidly metabolized, two previous studies on mussels have reported concentrations of up to 30ngg−1 wet weight of P in their flesh.
http://ift.tt/2h8BPP6
Publication date: November 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology, Volume 174
Author(s): Maria Meyer, Laura I. Garay, María Sol Kruse, Agustina Lara, Gisella Gargiulo-Monachelli, Michael Schumacher, Rachida Guennoun, Hector Coirini, Alejandro F. De Nicola, Maria Claudia Gonzalez Deniselle
Amyotrophic lateral sclerosis (ALS) is a devastating disorder characterized by progressive death of motoneurons. The Wobbler (WR) mouse is a preclinical model sharing neuropathological similarities with human ALS. We have shown that progesterone (PROG) prevents the progression of motoneuron degeneration. We now studied if allopregnanolone (ALLO), a reduced metabolite of PROG endowed with gabaergic activity, also prevents WR neuropathology. Sixty-day old WRs remained untreated or received two steroid treatment regimens in order to evaluate the response of several parameters during early or prolonged steroid administration. ALLO was administered s.c. daily for 5days (4mg/kg) or every other day for 32days (3, 3mg/kg), while another group of WRs received a 20mg PROG pellet s.c. for 18 or 60days. ALLO administration to WRs increased ALLO serum levels without changing PROG and 5 alpha dihydroprogesterone (5α-DHP), whereas PROG treatment increased PROG, 5α-DHP and ALLO. Untreated WRs showed higher basal levels of serum 5α-DHP than controls. In the cervical spinal cord we studied markers of oxidative stress or associated to trophic responses. These included nitric oxide synthase (NOS) activity, motoneuron vacuolation, MnSOD immunoreactivity (IR), brain derived neurotrophic factor (BDNF) and TrkB mRNAs, p75 neurotrophin receptor (p75NTR) and, cell survival or death signals such as pAKT and the stress activated kinase JNK. Untreated WRs showed a reduction of MnSOD-IR and BDNF/TrkB mRNAs, associated to high p75NTR in motoneurons, neuronal and glial NOS hyperactivity and neuronal vacuolation. Also, low pAKT, mainly in young WRs, and a high pJNK in the old stage characterized WŔs spinal cord. Except for MnSOD and BDNF, these alterations were prevented by an acute ALLO treatment, while short-term PROG elevated MnSOD. Moreover, after chronic administration both steroids enhanced MnSOD-IR and BDNF mRNA, while attenuated pJNK and NOS in glial cells. Long-term PROG also increased pAKT and reduced neuronal NOS, parameters not modulated by chronic ALLO. Clinically, both steroids improved muscle performance. Thus, ALLO was able to reduce neuropathology in this model. Since high oxidative stress activates p75NTR and pJNK in neurodegeneration, steroid reduction of these molecules may provide adequate neuroprotection. These data yield the first evidence that ALLO, a gabaergic neuroactive steroid, brings neuroprotection in a model of motoneuron degeneration.
http://ift.tt/2iyjhIc
Publication date: November 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology, Volume 174
Author(s): Yu H. Zhong, Jasbeer Dhawan, Joel A. Kovoor, John Sullivan, Wei X. Zhang, Dennis Choi, Anat Biegon
Accumulating evidence suggests that expression of aromatase, the enzyme responsible for the conversion of androgens to estrogens, is transiently upregulated in rat stroke models. It was further suggested that increased aromatase expression is linked to neuroinflammation and that it is neuroprotective in females. Our goal was to investigate aromatase upregulation in male rats subjected to experimental stroke in relationship to neuroinflammation, infarct and response to treatment with different putative neuroprotective agents. Intact male rats were subjected to transient (90min) middle cerebral artery occlusion (MCAO) and administered selfotel (N-methyl-d-aspartic acid (NMDA) receptor competitive antagonist), TPEN (a zinc chelator), a combination of the two drugs or vehicle, injected immediately after reperfusion. Animals were killed 14days after MCAO and consecutive brain sections used to measure aromatase expression, cerebral infarct volume and neuroinflammation. Quantitative immunohistochemistry (IHC) demonstrated increased brain aromatase expression in the peri-infarct area relative to contralesional area, which was partially abrogated by neuroprotective agents. There was no correlation between aromatase expression in the peri-infarct zone and infarct volume, which was reduced by neuroprotective agents. Microglial activation, measured by quantitative autoradiography, was positively correlated with infarct and inversely correlated with aromatase expression in the peri-infarct zone. Our findings indicate that focal ischemia upregulates brain aromatase in the male rat brain at 14days post surgery, which is within the time frame documented in females. However, the lack of negative correlation between aromatase expression and infarct volume and lack of positive correlation between microgliosis and aromatase do not support a major role for aromatase as a mediator of neuroprotection or a causal relationship between microglial activation and increased aromatase expression in male focal ischemia.
http://ift.tt/2h9siax
Publication date: November 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology, Volume 174
Author(s): Huili Wei, Hua Qu, Hang Wang, Baolan Ji, Yao Ding, Dan Liu, Yang Duan, Huimin Liang, Chuan Peng, Xiaoqiu Xiao, Huacong Deng
http://ift.tt/2iz1qAT
Publication date: Available online 1 November 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Peter Thomas
An essential role for GPER (formerly known as GPR30) in regulating mammalian reproduction has not been identified to date, although it has shown to be involved in the regulation a broad range of other estrogen-dependent functions. In contrast, an important reproductive role for GPER in the maintenance of oocyte meiotic arrest has been identified in teleost fishes, which is briefly reviewed here. Recent studies have clearly shown that ovarian follicle production of estradiol-17β (E2) maintains meiotic arrest in several teleost species through activation of GPER coupled to a stimulatory G protein (Gs) on oocyte plasma membranes resulting in stimulation of cAMP production and maintenance of elevated cAMP levels. Studies with denuded zebrafish oocytes and with microinjection of GPER antisense oligonucleotides into oocytes have demonstrated the requirement for both ovarian follicle production of estrogens and expression of GPER on the oocyte surface for maintenance of meiotic arrest. This inhibitory action of E2 on the resumption of meiosis is mimicked by the GPER-selective agonist G-1, by the GPER agonists and nuclear ER antagonists, ICI 182,780 and tamoxifen, and also by the xenoestrogen bisphenol-A (BPA) and related alkylphenols. GPER also maintains meiotic arrest of zebrafish oocytes through estrogen- and BPA-dependent GPER activation of epidermal growth factor receptor (EGFR) and mitogen-activated protein kinase (MAPK) signaling. Interestingly, progesterone receptor component 1 (PGRMC1) is also involved in estrogen maintenance of meiotic arrest through regulation of EGFR expression on the oocyte plasma membrane. The preovulatory surge in LH secretion induces the ovarian synthesis of progestin hormones that activate a membrane progestin receptor alpha (mPRα)/inhibitory G protein (Gi) pathway. It also increases ovarian synthesis of the catecholestrogen, 2-hydroxy-estradiol-17β (2-OHE2) which inhibits the GPER/Gs/adenylyl cyclase pathway. Both of these LH actions cause declines in oocyte cAMP levels resulting in the resumption of meiosis. GPER is also present on murine oocytes but there are no reports of studies investigating its possible involvement in maintaining meiotic arrest in mammals.
http://ift.tt/2h7NLQR
Publication date: Available online 1 November 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Hiroki Mano, Shinichi Ikushiro, Nozomi Saito, Atsushi Kittaka, Toshiyuki Sakaki
Split-luciferase techniques are widely used to detect protein-protein interaction and bioactive small molecules including some hormones and vitamins. Previously, we successfully expressed chimeric proteins of luciferase and the ligand binding domain (LBD) of the vitamin D receptor (VDR), LucC-LBD-LucN in COS-7 cells. The LucC-LBD-LucN biosensor was named split-luciferase vitamin D biosensor (SLDB). This biosensor can detect and discriminate between VDR agonists and antagonists in mammalian cells. In this study, we established an in vitro screening system for VDR ligands using the SLDB proteins expressed in Escherichia coli (E. coli) cells. Our in vitro screening system using cell lysate of recombinant E. coli cells could be completed within 30min, and its activity was unchanged after 10 freeze-thaw cycles. This highly sensitive and convenient system would be quite useful to screen VDR ligands with therapeutic potential for various bone-related diseases, age-related cognitive disorders, cancer, and immune disorders. In addition, our system might be applicable to diagnostic measurement of serum concentrations of 25-hydroxyvitamin D3 and 1α,25-dihydroxyvitamin D3.
http://ift.tt/2iz59hU
Publication date: Available online 28 October 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Yolandi Starczak, Daniel C. Reinke, Kate R. Barratt, Jackson W. Ryan, René St-Arnaud, Howard A. Morris, Rachel A. Davey, Gerald J. Atkins, Paul H. Anderson
Mature osteoclasts express the vitamin D receptor (VDR) and are able to synthesise and respond to 1,25(OH)2D3 via CYP27B1 enzyme activity. Whether vitamin D signalling within osteoclasts is necessary for the regulation of osteoclastic bone resorption in an in vivo setting is unclear. To determine the requirement for the VDR- and CYP27B1-mediated activity in mature osteoclasts, conditional deletion mouse models were created whereby either Vdr or Cyp27b1 gene was inactivated by breeding either Vdrfl/fl or Cyp27b1fl/fl mice with Cathepsin K-Cre transgenic mice (CstkCre) to generate CtskCre/Vdr−/− and CtskCre/Cyp27b1−/− mice respectively. To account for potential CtskCre-meaited off-target deletion of Vdr, Dmp1Cre were also used determine the effect of Vdr deletion in osteocytes. Furthermore, CtskCre/Vdr−/− mice were ovariectomised (OVX) to assess the role of VDR in osteoclasts under bone-loss conditions and bone marrow precursor cells were cultured under osteoclastogenic conditions to assess osteoclast formation. Six-week-old CtskCre/Vdr−/− female mice demonstrated a 15% decrease in femoral BV/TV (p<0.05). In contrast, BV/TV remained unchanged in CtskCre/Cyp27b1−/− mice as well as in Dmp1Cre/VDR−/− mice. When CtskCre/Vdr−/− mice were subjected to OVX, the bone loss that occurred in CtskCre/Vdr−/− was predominantly due to a diminished volume of thinner trabeculae when compared to control levels. These changes in bone volume in CtskCre/Vdr−/− mice occurred without an observable histological change in osteoclast numbers or size. However, while cultured bone marrow-derived osteoclasts from CtskCre/Vdr−/− mice were marginally increased when compared to VDRfl/fl mice, elevated expression of genes such as Cathepsin K, Nfatc1 and VATPase was observed. Collectively, these data indicate that the absence of VDR in mature osteoclasts causes exacerbated bone loss in young mice and during OVX which is associated with enhanced osteoclastic activity and without increased osteoclastogenesis.
http://ift.tt/2h6kypv
Publication date: Available online 26 October 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): M. Abboud, M.S. Rybchyn, Y.J. Ning, T.C. Brennan-Speranza, C.M. Girgis, J.E. Gunton, D.R. Fraser, R.S. Mason
The major circulating metabolite of vitamin D3, 25-hydroxycholecalciferol [25(OH)D], has a remarkably long half-life in blood for a (seco)steroid. Data from our studies and others are consistent with the hypothesis that there is a role for skeletal muscle in the maintenance of vitamin D status. Muscle cells internalise vitamin D-binding protein (DBP) from the circulation by means of a megalin/cubilin plasma membrane transport mechanism. The internalised DBP molecules then bind to actin and thus provide an intracellular array of high affinity binding sites for its specific ligand, 25(OH)D. There is evidence that the residence time for DBP in muscle cells is short and that it undergoes proteolytic degradation, releasing bound 25(OH)D. The processes of internalisation of DBP and its intracellular residence time, bound to actin, appear to be regulated. To explore whether 1,25-dihydroxycholecalciferol (calcitriol) has any effect on this process, cell cultures of myotubes and primary skeletal muscle fibers were incubated in a medium containing 10−10M calcitriol but with no added DBP. After 3hours pre-incubation with calcitriol, the net uptake of 25(OH)D by these calcitriol-treated cells over a further 4hours was significantly greater than that in vehicle-treated control cells. This was accompanied by a significant increase in intracellular DBP protein. However, after 16hours of pre-incubation with calcitriol, the muscle cells showed a significantly depressed ability to accumulate 25(OH)D compared to control cells over a further 4 or 16hours. These effects of pre-incubation with calcitriol were abolished in fibers from VDR-knockout mice. The effect was also abolished by the addition of 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS), which inhibits chloride channel opening. Incubation of C2 myotubes with calcitriol also significantly reduced retention of previously accumulated 25(OH)D after 4 or 8h. It is concluded from these in vitro studies that calcitriol can modify the DBP-dependent uptake and release of 25(OH)D by skeletal muscle cells in a manner that suggests some inducible change in the function of these cells.
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Publication date: Available online 18 October 2017
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Hai Jiang, Wenpei Bai, Wenjuan Wang, Ke Wang, Jing Jia, Jing Zhang, He Diao, Lihua Qin
The menopausal period, an inevitable physiological process for women, is frequently associated with physiological and psychological dysfunction attributable to substantial fluctuation and gradual decrease in female hormones induced by ovarian failure, leading to corresponding symptoms and diseases that impact multiple systems in the body to varying degrees. As prior studies have focused primarily on menopausal syndrome-related pathophysiological changes and hormone replacement therapy effects, here we approached menopausal disease incidence risk and pathogenesis through systemic plasma proteomics analysis. Female Sprague-Dawley rats were randomly divided into sham, ovariectomized, and estrogen treatment after ovariectomy groups (n=9 per group). Tandem Mass Tag quantitative proteomics analysis of their plasma identified over 900 proteins by MS. Between group fold change of >1.2 and p<0.05 (Student's t test) identified 121 (including 36 up-regulated and 85 down-regulated), 117 (69 up-regulated and 48 down-regulated), and 109 (41 up-regulated and 68 down-regulated) differentially expressed proteins between groups, respectively. Of these, 5 (GHR, LIFR, apoA IV, RTN, and Lin28b) were verified by parallel reaction monitoring to be reliable. Further application of optimized screening criteria and performance of a series of bioinformatics analyses allowed the selection of 35 optimal differentially expressed proteins. Gene ontology annotation results suggested that the differentially expressed proteins are mainly annotated as protein binding, cell, and single organism process in terms of molecular function, cell composition, and biological process, respectively. KEGG pathway analysis indicated that the PI3-Akt pathway has the highest aggregation degree of differentially expressed proteins. Protein-protein interaction analysis noted GLUT4 as an important node protein. This research is the first to comprehensively analyze plasma protein changes, together with estrogen efficacy, in ovariectomized rats. The findings facilitate our understanding of the molecular mechanism of systemic menopausal changes and provide valuable clues for developing diagnostic biomarkers for menopausal dysfunctions and selecting clinical therapeutic strategies.
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Publication date: 15 January 2018
Source:NeuroImage, Volume 165
Author(s): Michael Ebner, Karen K. Chung, Ferran Prados, M. Jorge Cardoso, Declan T. Chard, Tom Vercauteren, Sébastien Ourselin
Hospitals often hold historical MR image data printed on films without being able to make it accessible to modern image processing techniques. Having the possibility to recover geometrically consistent, volumetric images from scans acquired decades ago will enable more comprehensive, longitudinal studies to understand disease progressions. In this paper, we propose a consistent framework to reconstruct a volumetric representation from printed films holding thick single-slice brain MR image acquisitions dating back to the 1980's. We introduce a flexible framework based on semi-automatic slice extraction, followed by automated slice-to-volume registration with inter-slice transformation regularisation and slice intensity correction. Our algorithm is robust against numerous detrimental effects being present in archaic films. A subsequent, isotropic total variation deconvolution technique revitalises the visual appearance of the obtained volumes. We assess the accuracy and perform the validation of our reconstruction framework on a uniquely long-term MRI dataset where a ground-truth is available. This method will be used to facilitate a robust longitudinal analysis spanning 30 years of MRI scans.
Publication date: 15 January 2018
Source:NeuroImage, Volume 165
Author(s): Guilherme Blazquez Freches, Cristina Chavarrias, Noam Shemesh
The auditory pathway is widely distributed throughout the brain, and is perhaps one of the most interesting networks in the context of neuroplasticity. Accurate mapping of neural activity in the entire pathway, preferably noninvasively, and with high resolution, could be instrumental for understanding such longitudinal processes. Functional magnetic resonance imaging (fMRI) has clear advantages for such characterizations, as it is noninvasive, provides relatively high spatial resolution and lends itself for repetitive studies, albeit relying on an indirect neurovascular coupling to deliver its information. Indeed, fMRI has been previously used to characterize the auditory pathway in humans and in rats. In the mouse, however, the auditory pathway has insofar only been mapped using manganese-enhanced MRI. Here, we describe a novel setup specifically designed for high-resolution mapping of the mouse auditory pathway using high-field fMRI. Robust and consistent Blood-Oxygenation-Level-Dependent (BOLD) responses were documented along nearly the entire auditory pathway, from the cochlear nucleus (CN), through the superior olivary complex (SOC), nuclei of the lateral lemniscus (LL), inferior colliculus (IC) and the medial geniculate body (MGB). By contrast, clear BOLD responses were not observed in auditory cortex (AC) in this study. Diverse BOLD latencies were mapped ROI- and pixel-wise using coherence analysis, evidencing different averaged BOLD time courses in different auditory centers. Some degree of tonotopy was identified in the IC, SOC, and MGB in the pooled dataset though it could not be assessed per subject due to a lack of statistical power. Given the importance of the mouse model in plasticity studies, animal models, and optogenetics, and fMRI's potential to map dynamic responses to specific cues, this first fMRI study of the mouse auditory pathway paves the way for future longitudinal studies studying brain-wide auditory-related activity in vivo.
Publication date: 15 January 2018
Source:NeuroImage, Volume 165
Author(s): Kurt G. Schilling, Vaibhav Janve, Yurui Gao, Iwona Stepniewska, Bennett A. Landman, Adam W. Anderson
Diffusion magnetic resonance imaging (dMRI) is widely used to probe tissue microstructure, and is currently the only non-invasive way to measure the brain's fiber architecture. While a large number of approaches to recover the intra-voxel fiber structure have been utilized in the scientific community, a direct, 3D, quantitative validation of these methods against relevant histological fiber geometries is lacking. In this study, we investigate how well different high angular resolution diffusion imaging (HARDI) models and reconstruction methods predict the ground-truth histologically defined fiber orientation distribution (FOD), as well as investigate their behavior over a range of physical and experimental conditions. The dMRI methods tested include constrained spherical deconvolution (CSD), Q-ball imaging (QBI), diffusion orientation transform (DOT), persistent angular structure (PAS), and neurite orientation dispersion and density imaging (NODDI) methods. Evaluation criteria focus on overall agreement in FOD shape, correct assessment of the number of fiber populations, and angular accuracy in orientation. In addition, we make comparisons of the histological orientation dispersion with the fiber spread determined from the dMRI methods. As a general result, no HARDI method outperformed others in all quality criteria, with many showing tradeoffs in reconstruction accuracy. All reconstruction techniques describe the overall continuous angular structure of the histological FOD quite well, with good to moderate correlation (median angular correlation coefficient > 0.70) in both single- and multiple-fiber voxels. However, no method is consistently successful at extracting discrete measures of the number and orientations of FOD peaks. The major inaccuracies of all techniques tend to be in extracting local maxima of the FOD, resulting in either false positive or false negative peaks. Median angular errors are ∼10° for the primary fiber direction and ∼20° for the secondary fiber, if present. For most methods, these results did not vary strongly over a wide range of acquisition parameters (number of diffusion weighting directions and b value). Regardless of acquisition parameters, all methods show improved successes at resolving multiple fiber compartments in a voxel when fiber populations cross at near-orthogonal angles, with no method adequately capturing low to moderate angle (<60°) crossing fibers. Finally, most methods are limited in their ability to capture orientation dispersion, resulting in low to moderate, yet statistically significant, correlation with histologically-derived dispersion with both HARDI and NODDI methodologies. Together, these results provide quantitative measures of the reliability and limitations of dMRI reconstruction methods and can be used to identify relative advantages of competing approaches as well as potential strategies for improving accuracy.
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Striae have been reported to be one of the most common skin changes and a commonly encountered esthetic problem.
To analyze risk factors of striae not associated with pregnancy and verify if body build and composition influence striae distensae (SD) occurrence and visibility.
Eighty female students (40 with striae (the mean age 23.9 years, SD 2.05 years) and 40 without these lesions (24.7 years, SD 6.2 years)) were included in the study. The subjects were asked to fill out a questionnaire including questions concerning risk factors of SD. Body build and composition were examined using Tanita SC-331S Body Composition Analyzer.
Women without striae more often reported a history of intended weight loss (P < .0001), less frequently had a history of contraceptives intake (P < .001) and more often their family history of striae was negative or unknown (P = .01). Multivariate analysis including body build and composition parameters indicated BMI as risk factor of SD (P = .021; OR =1.155, 95% CI 1.006; 1.325).
History of contraceptives intake and a family history of striae are risk factors of SD occurrence, while weight loss can reduce the risk of these lesions. BMI appeared to be the risk factor of striae visibility, especially in abdomen, but not on the buttocks. Further clinical researches are needed to examine the pathophysiology of this condition and to inform patients about the possibility to reduce the risk of striae occurrence.
Publication date: February 2018
Source:Addictive Behaviors, Volume 77
Author(s): Ashley Acheson, Andrea S. Vincent, Andrew J. Cohoon, William R. Lovallo
Individuals with a family history of alcohol and other drug use disorders (FH+) are at increased risk for developing substance use disorders themselves relative to those with no such histories (FH−). Here we sought to identify key characteristics associated with FH+ status and alcohol and other drug use disorder status in a large cohort of FH+ and FH− young adults.We conducted principal component analyses on demographic, temperament, and cognitive measures differentiating 506 FH+ and 528 FH− young adults. Three principal components were identified, and these component scores were then used to predict the odds of being FH+ and the odds of having an alcohol or other drug use disorder. Component 1 consisted of measures indexing internalizing traits, with higher component scores indicating greater depressive, anxious, and emotional instability tendencies. Component 2 consisted of measures of externalizing traits as well as exposure to early life adversity (ELA), with higher scores indicating less impulse control, more antisocial behavior, and greater ELA exposure. Component 3 consisted of estimated intelligence, delay discounting, and demographic characteristics, with higher scores indicating lower estimated intelligence, greater discounting of delayed rewards, less education, and lower childhood socioeconomic status. For each 1-point increase in the Component 1, 2, and 3 scores, the odds of being classified FH+ increased by 2%, 8%, and 4%, respectively. Similar findings were observed when individuals with alcohol or other drug use disorders were removed from the analyses. Finally, greater Component 2 scores were also associated with increased odds of having an alcohol or other drug use disorder. Collectively, these findings provide a more comprehensive understanding of the FH+ phenotype in young adults and help form a basis for further studies on biological mechanisms underlying risk for substance use disorders. The present findings also provide further support for a prominent role of ELA in promoting risk for problem alcohol and other drug use.
http://ift.tt/2An340o
Publication date: February 2018
Source:Addictive Behaviors, Volume 77
Author(s): Jacob Jones, K. Nicole Jones, Jenny Peil
In January of 2014 the Regulate Marijuana like Alcohol Act or, Amendment 64, went into effect in Colorado. Even though it was the first state to enact recreational legalization, attitudes towards marijuana use have been changing for decades. Prompted by medical marijuana legalization, studies have found mixed results in regards to the impact that legalization has on frequency of use and abuse. With college students having the highest rates of use in the United States (U.S.), whether legal or not, it was important to explore the impact that legalization has on this population. In the current study, rates of marijuana and alcohol use in college students before and after recreational legalization were explored. Data was collected in four waves from October 2013 to March 2015, to be able to determine the trends in marijuana and alcohol use, and relationship between the substances. In addition, grade point average was measured as a possible consequence of marijuana use. We found the frequency of marijuana use in Colorado college students is much higher than the national average t(94445)=24.424, p<0.001, especially the percentage of daily or almost daily users, t(2191)=10.373, p<0.001. There were significant differences between the marijuana non-users and the once a week or more often but not daily marijuana users in grade point average, F(6, 227)=2.935, p<0.001. In addition, it seems that the relationship between alcohol and marijuana use in general is decreasing since the passing of Amendment 64, but not among the binge drinkers.
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In the attempt to exploit the potential of the monoecious fiber hemp cv. Futura 75 in new fields besides textile, cosmetics and food industry, its crop-residue given by leaves and inflorescences was subjected to hydrodistillation to obtain the essential oils. These are niche products representing an ideal candidate for the development of natural insecticides for the control and management of mosquito vectors, houseflies and moth pests. After GC-MS analysis highlighting a safe and legal chemical profile (THC in the range 0.004–0.012% dw), the leaf and inflorescence essential oils were investigated for the insecticidal potential against three insect targets: the larvae of Culex quinquefasciatus and Spodoptera littoralis and the adults of Musca domestica. The essential oil from inflorescences, showing (E)-caryophyllene (21.4%), myrcene (11.3%), cannabidiol (CBD, 11.1%), α-pinene (7.8%), terpinolene (7.6%), and α-humulene (7.1%) as the main components, was more effective than leaf oil against these insects, with LD50 values of 65.8 μg/larva on S. littoralis, 122.1 μg/adult on M. domestica, and LC50 of 124.5 μl/l on C. quinquefasciatus larvae. The hemp essential oil moderately inhibited the acetylcholinesterase (AChE), which is a target enzyme in pesticide science. Overall, these results shed light on the future application of fiber hemp crop-residue for the development of effective, eco-friendly and sustainable insecticides.