bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Novel Role of Nuclear and Membrane Receptor on Isoflavone-Induced Neuritogenesis and Synaptogenesis
Authors: Ariyani Winda , Miyazaki Wataru , Koibuchi Noriyuki 
Published: May 2021

Abstract
Thyroid hormone (TH) receptor (TR) and estrogen receptor (ER) play crucial roles in brain development. TR and ER are involved in dendrite growth, spines, and synapse formation in neurons. Soybean isoflavones, such as genistein, daidzein, and daidzein metabolite, S-equol are known to exert their action through TR, ER, and GPER1, a G-protein-coupled ER. However, the mechanisms of isoflavones action on brain development, especially during neuritogenesis and synaptogenesis, have not yet been extensively studied. We evaluated the effects of isoflavones using mouse primary cerebellar culture, astrocyte-enriched culture, Neuro-2A clonal cells, and co-culture with neurons and astrocytes. Soybean isoflavone augmented TH- or estradiol (E2)-mediated dendrite arborization of Purkinje cells. Such augmentation was suppressed by G15, a selective GPER1 antagonist, and ICI 182.780, an antagonist for ERs in both cultures. The knockdown of nuclear TRs or ERs also significantly reduced the dendrite arborization of Purkinje cells. It also increased the mRNA levels of TH-responsive genes, including Mbp, Bdnf, Rc3, Ntf3, Camk2b, Hr, and also Syn1, Syp, and Psd95 that are involved in synaptic plasticity. Isoflavones also increased the protein levels of synapsin-1, synaptophysin, and PSD95 in dendrite and membrane fraction of the cerebellar culture. To study further the molecular mechanism, we used Neuro-2A clonal cells. Isoflavones also induced neurite growth of Neuro-2A. The knockdown of TRs, ERs, and GPR30 by RNAi reduced isoflavones-induced neurite growth. Moreover, the co-culture study of Neuro-2A and astrocytes also showed an increase in isoflavones-induces neurite growth. In addition, isoflavones increased the localization of synapsin-1 or synaptophysin and F-actin in filopodia tips during Neuro-2A differentiation. The knockdown of nuclear ERs or GPR30 significantly reduced the number of filopodia and synapsin-1 or synaptophysin expression levels in neurite and membrane fractions. However, there are no significant effects of filopodia formation after co-culture with astrocytes. These results indicate that nuclear ERs and TRs play an essential role in isoflavones-induces neuritogenesis. Non-genomics signaling through membrane receptor and F-actin are necessary for the isoflavones-induces synaptogenesis. Astrocytes-neurons communication also increased isoflavones-induced neuritogenesis, but not synaptogenesis.
Androgen Receptor Blocker Improves the Cardiometabolic Profile in a Rat Model of Polycystic Ovary Syndrome, but at What Cost?
Authors: Pruett Jacob E , Everman Steven , Fernandez Edgar David Torres , Davenport Kacey , Romero Damian G , Cardozo Licy L Yanes 
Published: May 2021

Abstract
Introduction: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age. PCOS is characterized by androgen excess and ovulatory dysfunction high prevalence of cardiovascular risk factors such as increased blood pressure (BP), insulin resistance (IR), and obesity. We have demonstrated previously that exposing prepubertal female rats to dihydrotestosterone (DHT) leads to increase in food intake (FI), body weight (BW), BP, and IR. We tested the hypothesis that administration of the AR blocker bicalutamide (BICA) would decrease BP, IR, and obesity in PCOS model. As there are previous reports of severe hepatotoxicity with the AR blocker flutamide, we also examined BICA effects in the liver. Methods: Four-week old female Sprague Dawley rats implanted with DHT pellets (7.5mg/90 days) or placebo (PBO) were randomized to standard chow diet with or without the AR blocker bicalutamide (BICA) at a dose of 250 mg/kg/day throughout the study (n=10/group). BW and FI were measured weekly. BP and heart rate (HR) were measured by radiotelemetry. Fasting plasma was collected for IR (Homeostatic model assessment for IR, HOMA-IR). At euthanasia, the liver was collected, as well as plasma for gamma glutamyl transferase (GGT), alanine transaminase (ALT), and aspartate transaminase (AST) quantification. Results: PCOS rats had increased BW, FI, IR, and BP compared to PBO. BICA treatment had no impact on BW (285.3 ± 7.0 vs 270 ± 8.2 g, P=0.2) as well as FI and HR in PCOS. However, in PCOS, BICA decreased HOMA-IR (5.10 ± 0.40 vs 3.33 ± 0.31, P&lt;0.05) and BP (115.4 ± 0.7 vs 105.3 ± 0.2 mmHg, P&lt;0.01). Compared to PBO, PCOS+BICA rats had similar IR (3.83 ± 0.28 vs 3.33 ± 0.31, P=0.7) and BP (107.4 ± 0.8 vs 105.3 ± 0.2 mmHg, P=0.9). In addition, the liver weight to tibia length ratio was drastically increased by BICA in PCOS (222.9 ± 9.5 vs 360.4 ± 16.9 mg/mm, P&lt;0.0001) as well as GGT (0.88 ± 0.88 vs 11.67 ± 0.58 U/L, P&lt;0.0001), though it decreased AST (60.2 ± 6.9 vs 42.4 ± 1.9 U/L, P&lt;0.05) and had no impact on ALT. Conclusion: In summary, in a model of PCOS, BICA treatment abolished IR and BP, independent of FI, BW and HR. Prompt treatment with an AR blocker can normalize increased IR and BP triggered by androgen excess in females. Further studies need to be done to fully understand the effect of BICA in the liver in PCOS. The beneficial effect of AR blockers as a therapeutic option to improve the cardiometabolic profile in PCOS may be hampered by its liver toxicity.
DHT Causes Liver Steatosis via Transcriptional Regulation of SCAP in Lean female Mice
Authors: Andrisse Stanley , Myer Jessie , Bogle Dilip “Bobby” , Eregha Nicole , Lofton Taylor 
Published: May 2021

Abstract
Hyperandrogenemia (HA) and insulin resistance are hallmarks of polycystic ovary syndrome (PCOS). These hallmarks are also integral elements of non-alcoholic fatty liver disease (NALFD). Administering low dose dihydrotestosterone (DHT) induced a lean PCOS-like female mouse model. The molecular mechanism of HA-induced NAFLD has not been determined. We hypothesized that low dose DHT would interrupt hepatic lipid metabolism leading to NAFLD. We extracted white adipose tissue (WAT), liver, and skeletal muscle from control and low dose DHT female mice; and performed histological and biochemical lipid profiles, Western blot, immunoprecipitation, chromatin immunoprecipitation, and real-time quantitative PCR analyses. DHT lowered the 65 kD form of cytosolic SREBP1 in the liver and WAT compared to controls. However, DHT did not alter the levels of the active and inactive forms of SREBP2 in the liver and WAT. DHT increased SCAP protein expression and SCAP-SREBP1 binding via AR binding to intron-8 of SCAP leading to increased SCAP mRNA. FAS mRNA and protein expression was increased in liver of DHT mice. p-ACC levels were unaltered in liver but decreased in WAT. Other lipid metabolism pathways were examined in liver and WAT, but no changes were observed. Our findings suggest that DHT increased de novo lipogenic proteins resulting in increased NAFLD via regulation of SREBP1 in liver. We show that in the presence of DHT the SCAP-SREBP1 interaction is elevated leading to increased nuclear SREBP1 resulting in increased de novo lipogenesis. We propose that the mechanism of action is increased AR binding to an ARE in SCAP intron-8.
Epitranscriptomic Reader HNRNPA2B1 Confers Endocrine Resistance to Breast Cancer Cells
Authors: Klinge Carolyn M , Petri Belinda J , Piell Kellianne M 
Published: May 2021

Abstract
Despite new combination therapies improving survival of breast cancer patients with estrogen receptor α (ER+) tumors, the molecular mechanisms for endocrine-resistant metastatic disease remain unresolved. HNRNPA2B1 (Heterogeneous Nuclear Ribonucleoprotein A2/B1), an RNA binding protein that functions as reader of the N(6)-methyladenosine (m6A) mark in transcribed RNA, is upregualted in tamoxifen- and fulvestrant-resistant, estrogen receptor (ERα)+ LCC9 and LY2 cells derived from MCF-7 endocrine-sensitive luminal A breast cancer cells (1). The miRNA-seq transcriptome of MCF-7 cells transiently overexpressing HNRNPA2B1 (A2B1) identified gene ontology (GO) pathways including “cellular response to steroid hormone signaling and estradiol” and “positive regulation of protein ser/thr kinase activity”. Modest (~ 4.5-fold) stable HNRNPA2B1 overexpression in MCF-7 cells (MCF-7-A2B1) results in ablation of growth inhibition by 4-hydroxytamoxifen (4-OHT) and fulvestrant. This was not due to loss or decrease of ERα; in fact, ERα was increased. Conversely, transient knockdown of HNRNPA2B1 in LCC9 and LY2 cells sensitized the cells to growth inhibition by 4-OHT and fulvestrant while reducing ERα. MCF-7-A2B1 cells showed increased migration, invasion, clonogenicity, soft agar colony size, and markers of epithelial-to-mesenchymal transition. Like LCC9 cells, MCF-7-A2B1 cells showed activation of AKT and MAPK and high androgen receptor (AR). Treatment of MCF-7-A2B1 cells with either PI3K inhibitor Wortmannin or MEK inhibitor PD98059 inhibited soft agar colony formation and reduced colony size. Knockdown of HNRNPA2B1 in MCF-7-A2B1 reduces clonogenicity, but had no effect on the clonogenicity of either LCC9 or LY2 cells. These data suggest a role for HNRNPA2B1 in promoting the initiation of acquired endocrine-resistance by activating ser/thr kinase growth factor signaling pathways. Selective inhibition of HNRNPA2B1 may be a target to prevent acquistion of endocrine therapy resistance, but not treat established metastatic disease. Reference: (1) Klinge CM, Piell KM, Tooley CS, Rouchka EC. HNRNPA2/B1 is upregulated in endocrine-resistant LCC9 breast cancer cells and alters the miRNA transcriptome when overexpressed in MCF-7 cells. Scientific reports 2019; 9:9430
Estrogen Receptor Alpha Is Required to Protect Daily Metabolic Rhythms From Disruption by High-Fat Feeding in Female Mice
Authors: Omotola Oluwabukola B , Pendergast Julie S 
Published: May 2021

Abstract
The circadian system is a critical regulator of obesity in male mice, but its role in females is poorly understood. In our previous studies we found that estrogen regulates daily rhythms in female mice to confer resistance to diet-induced obesity, but the mechanism is unknown. Estrogen signals via the classical estrogen receptor alpha (ERα) to regulate metabolism and obesity. Therefore, in this study we tested the hypothesis that estrogen regulates daily metabolic rhythms in females via ERα. To do so, we studied daily rhythms in female global ERα knockout (ERα KO) with the circadian reporter, PERIOD2::LUCIFERASE, mice fed high-fat diet for 6 weeks. ERα KO female mice became obese and hyperglycemic when fed high-fat diet, while wild-type females were resistant to diet-induced obesity. Chronic high-fat diet feeding also reduced the amplitude of the daily rhythm of eating behavior in ERα KO, but not wild-type, female mice. In wild-type females, the amplitude of the locomotor activity rhythm increased during high-fat feeding. In contrast, high-fat feeding decreased the amplitude of the activity rhythm in ERα KO females. The temporal relationship between central and peripheral circadian tissue clocks was disrupted by high-fat feeding in ERα KO females since the phase of the liver PERIOD2::LUCIFERASE rhythm was advanced 4 hours by high-fat feeding in ERα KO mice compared to wild-type females. Taken together these results show that estrogen signals via ERα to protect daily metabolic rhythms from disruption by high-fat feeding in female mice.
Glucocorticoid Mediated Transcriptional Activity in Human Corneal Epithelial Cells Lacking the Glucocorticoid Receptor
Authors: Jonsson Andrea Joyce , Ennis Lydia , Cidlowski John A , Kadmiel Mahita 
Published: May 2021

Abstract
The cornea is the dome-shaped transparent outermost layer of the eye, forming a physical barrier to protect the internal structures of the eye. Glucocorticoids are a mainstay in the treatment of ophthalmic diseases for their anti-inflammatory and anti-angiogenic properties. However, high doses or chronic use of glucocorticoid therapy can lead to vision-impairing effects such as increase in intraocular pressure and the formation of cataracts. The exact signaling pathways responsible for these undesirable effects of glucocorticoid use is poorly understood. One of the major molecular actions of glucocorticoids is to regulate transcription through its cognate nuclear receptor, the glucocorticoid receptor. We have previously reported the effect of glucocorticoids on global gene expression and their role in wound healing and barrier function in immortalized human corneal epithelial cells (HCE-T). In the current study, we knocked down glucocorticoid receptor using siRNA (GRKD) to determine the function of the glucocorticoid receptor in HCE-T cells. Successful knockdown of glucocorticoid receptor was confirmed by RT-PCR and immunoblot experiments. Genome-wide microarray analysis was performed and an FDR adjusted p value less than 0.01 was considered the cut off to create the list of differentially expressed genes (DEGs). Comparison of GRKD cells to HCE-T cells expressing endogenous glucocorticoid receptor (referred as NTC for No Target Control siRNA) revealed that expression of 2150 genes was altered in HCE-T cells when glucocorticoid receptor was knocked down, indicating that glucocorticoid receptor in corneal epithelial cells regulates a large cohort of genes. Inhibition of matrix metalloproteases, granulocyte adhesion and diapedesis, cyclins and cell cycle regulation were the top canonical pathways predicted by Ingenuity Pathway Analysis (IPA) to be altered in GRKD cells. In a 6-hour treatment with dexamethasone (Dex), a synthetic glucocorticoid, or with vehicle as a control, NTC cells had 2039 Dex-regulated genes, while Dex was still able to regulate 1087 genes in GRKD cells. Of these 1087 genes, 895 genes were uniquely regulated by Dex in GRKD cells suggesting that glucocorticoids might be signaling through another receptor in corneal epithelial cells. The top canonical pathways predicted to be altered by Dex in GRKD cells included PI3K/ATK Signaling, ERK5 Signaling, Prostrate Cancer Signaling, Aldosterone Signaling in Epithelial Cells, and PPAR signaling. These findings suggest that Dex could regulate large cohorts of genes through other nuclear receptors in corneal epithelial cells. Given the wide use of ophthalmic Dex in forms including eyedrops, ointments, gels, and implants, it is of clinical significance to understand the molecular actions of synthetic glucocorticoids since they appear to be ligands for multiple nuclear receptors in ocular cells and tissues.
Inhibition of Estrogen Signaling Reverses Established Inguinal Hernias
Authors: Potluri Tanvi , Taylor Matthew Joseph , Zhao Hong , Bulun Serdar Ekrem 
Published: May 2021

Abstract
Background: An inguinal hernia occurs when an intestinal loop or fat pushes through a weak spot in the lower abdominal muscle (LAM), causing a painful bulge that has the potential to cause bowel obstruction. Despite a high prevalence in men (~25%), non-surgical approaches are not available to treat this disease. We recently found a critical role of estrogen and estrogen receptor alpha (ERα) in inguinal hernia formation. To examine this further, we use a humanized aromatase mouse model (Aromhum) where all of the male mice develop scrotal hernias as a pre-clinical model to test the first pharmacological intervention for inguinal hernias. These mice are utilized because their skeletal muscle tissue contains aromatase and produces estradiol (E2), which acts via ERα in the LAM stromal fibroblasts and leads to fibrosis and muscle atrophy. Hypothesis: E2-ERα modulation can inhibit and reverse the formation of inguinal hernias in Aromhum mice by reducing LAM fibrosis and atrophy. Results: We tested three types of treatments to inhibit E2-ERα signaling: letrozole, fulvestrant, and raloxifene. Letrozole, an aromatase inhibitor, was shown to inhibit hernia formation and reversed small (150-175 mm2) scrotal hernias (n = 10-15/group, p&lt;0.0001). The LAM tissues also showed a reduction in fibrosis (n = 5-8/group, p = 0.0004) and a concurrent increase in myofiber cross-sectional area (n = 5-8, p=0.0356) compared to placebo-treated mice. Similarly, fulvestrant and raloxifene, E2-ERα antagonists, also inhibited hernia formation (n = 10-15/group). Most interestingly, both drugs reversed large and severe hernias (&gt;200 mm2, n = 10-15/group), accompanied by a decrease in muscle fibrosis and increase in myofiber cross-sectional area (ongoing study, n = 10-11, p&lt;0.0001) compared to placebo mice. The drug-treated mice had lower expression of pro-fibrotic genes such as Mmp3, Emb, Spon2, Timp1, and Tgfb1 in the LAM tissues compared to placebo-treated LAM. Furthermore, we analyzed the differences in extracellular matrix producing genes and muscle regeneration markers between the placebo and drug-treated muscle tissues. Conclusion: We find that inhibition of the E2-ERα signaling pathway can reverse mild or severe inguinal hernias. Successful treatment is accompanied by decreased skeletal muscle fibrosis and reversal of myocyte atrophy. These interventions are promising non-surgical treatment options for patients suffering from severe and recurrent inguinal hernias.
Maternal Total Cortisol Levels in Early Pregnancy Depends on Fetal Sexual Dimorphism. But Finally No Association With Birth Weight
Authors: Twickler Theodorus Bartholomeus , Vrijkotte Tanja 
Published: May 2021

Abstract
Enhanced maternal cortisol levels may have a negative impact on fetal development with a higher risk for diseases later in life, e.g. premature cardiovascular disease and type 2 diabetes. Prior studies do assume even a sex specific impact. Currently, it is unknown whether sexual dimorphism in the fetus could display a different maternal cortisol level that is associated with intra uterine growth. In the present study (performed in the Amsterdam Born Children and their Development (ABCD) –cohort), we evaluated in 3049 pregnant women (in early pregnancy) whether fetal sex is related to the level of maternal serum total cortisol and whether this contributes to fetal growth. Maternal serum total cortisol levels increased along early pregnancy from on average 390±22 nmol/L (at 5th week of pregnancy) to 589±15 nmol/L (at 20th week of pregnancy). The presence of a female fetus was associated with higher maternal total cortisol level in a distinctive time interval along early pregnancy; before 11th week of pregnancy, no difference, and from the 12th week of pregnancy a difference of 15 (SE:7) nmol/L between mothers carrying a male vs female fetus was found and that difference increased to 45 (22) nmol/L at 20th week of pregnancy (p-for-interaction=0.05). Maternal serum total cortisol levels were negatively associated with maternal age, pBMI, smoking and parity, the last one also increasing with pregnancy duration. After adjusting for these factors, the association between fetal sex and maternal cortisol remained Maternal serum total cortisol levels were significantly associated with birth weight, standardized for pregnancy duration (ß -.22; SE:0.06; P &lt; 0.001). Girls had a significantly lower birth weight (-132 SE:16 gram) compared to males, however, maternal cortisol did not alter the association between fetal sex and birth weight to a relevant degree indicating no mediation by maternal cortisol. In early pregnancy, the maternal total cortisol levels are related to fetal sex. However this difference in maternal total cortisol level was finally not related to birth weight.
Persistent COUP-TFII Expression Underlies the Myopathy and Impaired Muscle Regeneration Observed in Resistance to Thyroid Hormone-Alpha
Authors: Aguiari Paola , Liu Yan-Yun , Petrosyan Astgik , Cheng Sheue-Yann , Brent Gregory A , Perin Laura , Milanesi Anna 
Published: May 2021

Abstract
Myopathic changes, including muscular dystrophy and weakness, are commonly described in hypothyroid and hyperthyroid patients. Thyroid hormone signaling, via activation of thyroid nuclear receptor alpha (THRA), plays an essential role in maintaining muscle mass, function, and regeneration. A mouse model of resistance to thyroid hormone carrying a frameshift mutation in the THRA gene (THRA-PV) is associated with accelerated skeletal muscle loss with aging and impaired regeneration after injury(1,2). We previously demonstrated that the expression of nuclear orphan receptor chicken ovalbumin upstream promoter-factor II (COUP-TFII, or Nr2f2) persists during myogenic differentiation in THRA-PV myoblasts and skeletal muscle of aged THRA- PV mice. COUP-TFII is known to regulate myogenesis negatively and has a role in Duchenne-like Muscular Dystrophies(3). COUP-TFII physically and functionally interacts with THRA in primary myoblasts isolated from WT and THRA-PV mice, as demonstrated via co-immunoprecipitation and chromatin-immunoprecipitation. We observed that satellite cells from THRA-PV mice display impaired myoblast proliferation and in vitro myogenic differentiation compared to WT cells. However, the silencing of COUP-TFII expression using siRNA probes restores in vitro myogenic potential of THRA-PV myoblasts and shifts the mRNA expression profile closer to WT myoblasts, with a higher proliferation of myoblasts and a higher number of fully differentiated myotubes after 5 days of myogenic induction. Moreover, RNAseq analysis on myoblasts from THRA-PV mice after COUP-TFII knockdown shows that COUP-TFII silencing reverses the transcriptomic profile of THRA-PV myoblasts and results in reactivation of pathways involved in muscle function and extracellular matrix remodeling/deposition. These findings indicate that the persistent COUP-TFII expression in THRA-PV mice is responsible for the abnormal muscle phenotype. In conclusion, COUP-TFII and THRA cooperate during murine post-natal myogenesis, and COUP-TFII is critical for the accelerated skeletal muscle loss with aging and impaired muscle regeneration after injury in THRA-PV mice. These studies can help increase our knowledge of the mechanisms involved in thyroid hormone signaling during skeletal muscle regeneration, ultimately increasing the possibility of designing more specific treatments for patients with thyroid hormone-induced myopathies. References: 1. Milanesi, A., et al., Endocrinology 2016; 2. Kaneshige, M. et al., Proc Natl Acad Sci U S 2001; 3. Lee HJ, et al, Sci Rep. 2017.