Non-genomic Effects Research Articles

G-Protein-Coupled Estrogen Receptor (GPER)-Specific Agonist G1 Induces ER Stress Leading to Cell Death in MCF-7 Cells.

The G-protein-coupled estrogen receptor (GPER) mediates rapid non-genomic effects of estrogen. Although GPER is able to induce proliferation, it is down-regulated in breast, ovarian and colorectal cancer. During cancer progression, high expression levels of GPER are favorable for patients’ survival. The GPER-specific agonist G1 leads to an inhibition of cell proliferation and an elevated level of intracellular calcium (Ca2+). The purpose of this study is to elucidate the mechanism of G1-induced cell death by focusing on the connection between G1-induced Ca2+ depletion and endoplasmic reticulum (ER) stress in the estrogen receptor positive breast cancer cell line MCF-7. We found that G1-induced ER Ca2+ efflux led to the activation of the unfolded protein response (UPR), indicated by the phosphorylation of IRE1α and PERK and the cleavage of ATF6. The pro-survival UPR signaling was activated via up-regulation of the ER chaperon protein GRP78 and translational attenuation indicated by eIF2-α phosphorylation. However, the accompanying pro-death UPR signaling is profoundly activated and responsible for ER stress-induced cell death. Mechanistically, PERK-phosphorylation-induced JNK-phosphorylation and IRE1α-phosphorylation, which further triggered CAMKII-phosphorylation, are both implicated in G1-induced cell death. Our study indicates that loss of ER Ca2+ is responsible for G1-induced cell death via the pro-death UPR signaling.

Calcifediol Decreases Interleukin-6 Secretion by Cultured Human Trophoblasts From GDM Pregnancies.

Gestational diabetes mellitus (GDM) is often characterized by low maternal calcifediol (25OHD) and high inflammation levels. This study aimed to determine whether placental protein expressions of CYP27B1, vitamin D receptor (VDR), and CYP24A1 are impaired in GDM and to investigate the effect of a 25OHD treatment on IL-6 secretion by GDM trophoblasts compared with normoglycemic (NG) trophoblasts. Placental tissue samples were harvested to determine protein expression of CYP27B1, VDR, and CYP24A1 by immunoblots. Isolated trophoblasts were stimulated with 25OHD concentrations (25 to 2000 nM) once a day for 3 days and IL-6 secretion was quantified (ELISA). We recruited 17 NG women, 19 women with GDM treated with diet and exercise alone (GDM-d) and 9 women with GDM who necessitated insulin therapy (GDM-i). Protein expressions of CYP27B1 and VDR were significantly higher in placental tissue from GDM-d women compared with NG women (both P = 0.02), whereas no differences were detected between GDM-i and NG placental tissues. In cultured trophoblasts (two groups; n = 5 NG and n = 5 GDM-d), exposure to increasing 25OHD concentrations significantly decreased IL-6 secretion in the GDM-d group only (P = 0.006). After treatment with 25OHD (2000 nM), IL-6 secretion was lower in the GDM-d group compared with the NG group (P = 0.03). Our results suggest an upregulation of the VDR-1,25(OH)2D complex bioavailability in GDM-d placentas, possibly reflecting a compensatory mechanism aiming to ensure that vitamin D can exert its genomic and nongenomic effects in the target cells of the placental-fetal unit. Our findings support an anti-inflammatory effect of vitamin D at the feto-maternal interface in GDM-d pregnancies.

Skeletal effects of nongenomic thyroid hormone receptor beta signaling.

Thyroid hormone (TH) levels increase rapidly during the prepubertal growth period in mice, and this change is necessary for endochondral ossification of the epiphyses. This effect of TH on epiphyseal chondrocyte hypertrophy is mediated via TRβ1. In addition to its traditional genomic signaling role as a transcription factor, TRβ1 can also exert nongenomic effects by interacting with other signaling molecules such as PI3K. To investigate the role of nongenomic TRβ1 signaling in endochondral ossification, we evaluated the skeletal phenotype of TRβ147F mutant mice which exhibit a normal genomic response of TRβ1 to TH, but the nongenomic response through the PI3K pathway is impaired. Using microCT, we found that 13-week-old TRβ147F mice had significantly less trabecular bone mass at three sites. Histomorphometric analyses revealed that mineralizing surface to bone surface and BFR/BS were reduced in the mutant mice. Mechanistically, we found that activation of TRβ increased Alp and Osx expression in control but not TRβ147F osteoblasts. Since canonical β-catenin signaling has been implicated in mediating nongenomic TRβ-PI3K signaling, we evaluated the effect of TRβ1 activation on β-catenin target gene expression in MC3T3-E1 pre-osteoblasts. We found that β-catenin target genes were increased, suggesting that nongenomic TRβ1-PI3K pathway modulation of β-catenin signaling may mediate TRβ1 effects on osteoblast differentiation. Together, these results suggest that TH acting through TRβ1 regulates endochondral ossification in part via nongenomic signaling in mice. Further investigation of this nongenomic mechanism of TRβ1 signaling could lead to novel therapeutic targets for treatment and prevention of osteoporosis.

The Role of Thyroid Hormones in Hepatocyte Proliferation and Liver Cancer

Thyroid hormones T3 and T4 (thyroxine) control a wide variety of effects related to development, differentiation, growth and metabolism, through their interaction with nuclear receptors. But thyroid hormones also produce non-genomic effects that typically start at the plasma membrane and are mediated mainly by integrin αvβ3, although other receptors such as TRα and TRβ are also able to elicit non-genomic responses. In the liver, the effects of thyroid hormones appear to be particularly important. The liver is able to regenerate, but it is subject to pathologies that may lead to cancer, such as fibrosis, cirrhosis, and non-alcoholic fatty liver disease. In addition, cancer cells undergo a reprogramming of their metabolism, resulting in drastic changes such as aerobic glycolysis instead of oxidative phosphorylation. As a consequence, the pyruvate kinase isoform M2, the rate-limiting enzyme of glycolysis, is dysregulated, and this is considered an important factor in tumorigenesis. Redox equilibrium is also important, in fact cancer cells give rise to the production of more reactive oxygen species (ROS) than normal cells. This increase may favor the survival and propagation of cancer cells. We evaluate the possible mechanisms involving the plasma membrane receptor integrin αvβ3 that may lead to cancer progression. Studying diseases that affect the liver and their experimental models may help to unravel the cellular pathways mediated by integrin αvβ3 that can lead to liver cancer. Inhibitors of integrin αvβ3 might represent a future therapeutic tool against liver cancer. We also include information on the possible role of exosomes in liver cancer, as well as on recent strategies such as organoids and spheroids, which may provide a new tool for research, drug discovery, and personalized medicine.

Glucocorticoid and Mineralocorticoid Receptors in the Brain: A Transcriptional Perspective.

Adrenal glucocorticoid hormones are crucial for maintenance of homeostasis and adaptation to stress. They act via the mineralocorticoid receptors (MRs) and glucocorticoid receptors (GRs)—members of the family of nuclear receptors. MRs and GRs can mediate distinct, sometimes opposite, effects of glucocorticoids. Both receptor types can mediate nongenomic steroid effects, but they are best understood as ligand-activated transcription factors. MR and GR protein structure is similar; the receptors can form heterodimers on the DNA at glucocorticoid response elements (GREs), and they share a number of target genes. The transcriptional basis for opposite effects on cellular physiology remains largely unknown, in particular with respect to MR-selective gene transcription. In this review, we discuss proven and potential mechanisms of transcriptional specificity for MRs and GRs. These include unique GR binding to “negative GREs,” direct binding to other transcription factors, and binding to specific DNA sequences in conjunction with other transcription factors, as is the case for MRs and NeuroD proteins in the brain. MR- and GR-specific effects may also depend on specific interactions with transcriptional coregulators, downstream mediators of transcriptional receptor activity. Current data suggest that the relative importance of these mechanisms depends on the tissue and physiological context. Insight into these processes may not only allow a better understanding of homeostatic regulation but also the development of drugs that target specific aspects of disease.

Parental Effects and Climate Change: Will Avian Incubation Behavior Shield Embryos from Increasing Environmental Temperatures?

A major driver of wildlife responses to climate change will include non-genomic effects, like those mediated through parental behavior and physiology (i.e., parental effects). Parental effects can influence lifetime reproductive success and survival, and thus population-level processes. However, the extent to which parental effects will contribute to population persistence or declines in response to climate change is not well understood. These effects may be substantial for species that exhibit extensive parental care behaviors, like birds. Environmental temperature is important in shaping avian incubation behavior, and these factors interact to determine the thermal conditions embryos are exposed to during development, and subsequently avian phenotypes and secondary sex ratios. In this article, we argue that incubation behavior may be an important mediator of avian responses to climate change, we compare incubation strategies of two species adapted to different thermal environments nesting in extreme heat, and we present a simple model that estimates changes in egg temperature based on these incubation patterns and predicted increases in maximum daily air temperature. We demonstrate that the predicted increase in air temperature by 2100 in the central USA will increase temperatures that eggs experience during afternoon off-bouts and the proportion of nests exposed to lethal temperatures. To better understand how species and local adaptations and behavioral-plasticity of incubation behavior will contribute to population responses to climate change comparisons are needed across more avian populations, species, and thermal landscapes.

Renal Fibrosis, Immune Cell Infiltration and Changes of TRPC Channel Expression after Unilateral Ureteral Obstruction in Trpc6-/- Mice

The transient receptor potential cation channel subfamily C member 6 (TRPC6) is a Ca2+-permeable nonselective cation channel and has received recent attention because of its capability to promote chronic kidney disease (CKD). The aims of this study were (i) to examine whether deletion of TRPC6 impacts on renal fibrosis and inflammatory cell infiltration in an early CKD model of unilateral ureter obstruction (UUO) in mice; and (ii) whether TRPC6-deficiency as well as UUO affect the regulation of TRPC expression in murine kidneys. Wild-type (WT), Trpc6-knockout (Trpc6-/-) and New Zealand obese (NZO) mice underwent sham operation or unilateral ureteral obstruction (UUO). The kidneys were harvested 7 days after surgery. We examined renal fibrosis and inflammatory cell infiltration by histological and immunohistochemical staining. The mRNA expression of TRPC members and markers of fibrosis and inflammation in kidney were assessed by using real-time quantitative reverse transcription PCR. Histological and immunohistochemical analyses revealed less inflammatory cell infiltration (F4/80 and CD3) in UUO kidneys of Trpc6-/- mice compared to UUO kidneys of WT mice as well as less fibrosis. Genomic deletion of TRPC6 also affected the expression of pro-fibrotic genes in UUO Trpc6-/- kidneys compared to UUO WT kidneys while the expression of pro-inflammatory genes did not differ. UUO caused marked up-regulation of Trpc6 and down-regulation of Trpc1 mRNA in kidneys of WT and NZO mice. Trpc3 mRNA expression was significantly elevated in kidneys of Trpc6-/- mice underwent UUO while the levels did not change in kidneys of neither WT nor in NZO mice underwent UUO. TRPC6 contributes to renal fibrosis and immune cell infiltration in the UUO mouse model. Therefore, inhibition of TRPC6 emerges as a promising novel therapeutic strategy for treatment of chronic kidney failure in chronic obstructive nephropathy. However, confounding genomic and non-genomic effects of other TRPC channels should be taken into consideration to fully comprehend the renoprotective potential of targeting TRPC6 therapeutically under chronic kidney damaging conditions.

MPRs represent a novel target for PRL inhibition in experimental prolactinomas.

Membrane progesterone receptors are known to mediate rapid nongenomic progesterone effects in different cell types. Recent evidence revealed that mPRα is highly expressed in the rat pituitary, being primarily localized in lactotrophs, acting as an intermediary of P4-inhibitory actions on prolactin secretion. The role of mPRs in prolactinoma development remains unclear. We hypothesize that mPR agonists represent a novel tool for hyperprolactinemia treatment. To this end, pituitary expression of mPRs was studied in three animal models of prolactinoma. Expression of mPRs and nuclear receptor was significantly decreased in tumoral pituitaries compared to normal ones. However, the relative proportion of mPRα and mPRβ was highly increased in prolactinomas. Interestingly, the selective mPR agonist (Org OD 02-0) significantly inhibited PRL release in both normal and tumoral pituitary explants, displaying a more pronounced effect in tumoral tissues. As P4 also regulates PRL secretion indirectly, by acting on dopaminergic neurons, we studied mPR involvement in this effect. We found that the hypothalamus has a high expression of mPRs. Interestingly, both P4 and OrgOD 02-0 increased dopamine release in hypothalamus explants. Moreover, in an in vivo treatment, that allows both, pituitary and hypothalamus actions, the mPR agonist strongly reduced the hyperprolactinemia in transgenic females carrying prolactinoma. Finally, we also found and interesting gender difference: males express higher levels of pituitary mPRα/β, a sex that does not develop prolactinoma in these mice models. Taken together, these findings suggest mPRs activation could represent a novel tool for hyperprolactinemic patients, especially those that present resistance to dopaminergic drugs.

Progesterone decrease plasma membrane in human sperm with subnormal hypoosmotic swelling test scores

BackgroundProgesterone (P4) is known as a female hormone affecting oocyte maturation and developing uterine wall. A proteomic study identified several receptors including P4 receptors on human sperm. The role of P4 in human sperm cells remains unknown as to whether P4 has non-genomic effects on human sperm. The present study aims to determine the effect of progesterone (P4) on the hyperactivated motility and membrane integrity of human sperm cells.MethodsSemen from normal individuals was obtained from donors. The semen was washed by gradient density centrifugation. P4 was added to each semen sample to final concentrations of 0 (control), 250, 500, 750 and 1000 ng/mL. After the sample treatment was completed, the sperm membrane integrity was assessed with the hypoosmotic swelling test (sodium citrate dihydrate and D-fructose) and the hyperactivated sperm motility parameter was determined with the Computer Assisted Sperm Analyzer [CASA] (Hamilton Thorne, IVOS II, USA). The percentage was then compared between the treatment groups and the control group. The percentage differences were analyzed with the Sigmastat version 2.0 statistical program.ResultsAdministration of P4 increased sperm hyperactivated motility when compared with the control group at a concentration of 500 ng/mL, but the increase was statistically not signicant (p>0.05). In contrast, P4 decreased sperm membrane integrity significantly (p=0.042). And the mean of plasma membrane integrity in all groups was subnormal hypoosmotic swelling test score. ConclusionProgesterone administration tends to increase sperm hyperactivated motility. The integrity of plasma sperm membrane was affected by progesterone.

EPHB6 controls catecholamine biosynthesis by up-regulating tyrosine hydroxylase transcription in adrenal gland chromaffin cells

EPHB6 is a member of the erythropoietin-producing hepatocellular kinase (EPH) family and a receptor tyrosine kinase with a dead kinase domain. It is involved in blood pressure regulation and adrenal gland catecholamine (CAT) secretion, but several facets of EPHB6-mediated CAT regulation are unclear. In this study, using biochemical, quantitative RT-PCR, immunoblotting, and gene microarray assays, we found that EPHB6 up-regulates CAT biosynthesis in adrenal gland chromaffin cells (AGCCs). We observed that epinephrine content is reduced in the AGCCs from male Ephb6-KO mice, caused by decreased expression of tyrosine hydroxylase, the rate-limiting enzyme in CAT biosynthesis. We demonstrate that the signaling pathway from EPHB6 to tyrosine hydroxylase expression in AGCCs involves Rac family small GTPase 1 (RAC1), MAP kinase kinase 7 (MKK7), c-Jun N-terminal kinase (JNK), proto-oncogene c-Jun, activator protein 1 (AP1), and early growth response 1 (EGR1). On the other hand, signaling via extracellular signal-regulated kinase (ERK1/2), p38 mitogen-activated protein kinase, and ELK1, ETS transcription factor (ELK1) was not affected by EPHB6 deletion. We further report that EPHB6's effect on AGCCs was via reverse signaling through ephrin B1 and that EPHB6 acted in concert with the nongenomic effect of testosterone to control CAT biosynthesis. Our findings elucidate the mechanisms by which EPHB6 modulates CAT biosynthesis and identify potential therapeutic targets for diseases, such as hypertension, caused by dysfunctional CAT biosynthesis.

Estrogen Signaling in ERα-Negative Breast Cancer: ERβ and GPER.

Estrogen receptors are important regulators of the growth of breast tumors. Three different receptors for estrogens have been identified in breast tumors, two nuclear receptors, ERα and ERβ, and a G-protein coupled estrogen receptor 1 (GPER) that initiates non-genomic effects of estrogens in the cytosol. Recent findings show that the stimulation of cytoplasmic ERα and ERβ also triggers non-genomic signaling pathways. The treatment of breast cancer with anti-estrogens depends on the presence of ERα. About 40% of all breast cancers, however, do not express ERα. One subgroup of these tumors overexpress Her-2, another important group is designated as triple-negative breast cancer, as they neither express ERα, nor progesterone receptors, nor do they overexpress Her-2. This review addresses the signaling of ERβ and GPER in ERα-negative breast tumors. In addition to the well-established EGF-receptor transactivation pathways of GPER, more recent findings of GPER-dependent activation of FOXO3a, the Hippo-pathway, and HOTAIR-activation are summarized.

Non-Genomic Effects of Aldosterone.

Encouraging changes in the steroid hormone receptor field from initially questioning the role of non-genomic actions of steroid hormones to acceptance of the concept that the acute, membrane-centric actions are linked and/or regulate the nuclear actions. The focus of this chapter is how the non-genomic effects are linked to the longer lasting, genomic actions of aldosterone. By non-genomic we refer to the rapid actions that occur within minutes do not require transcription or translation and occur in both classical MR target organs (kidney and colon) and non-epithelial tissues (blood vessels, heart, and adipose). The mechanism of rapid non-genomic actions of aldosterone varies between tissues. As a result, this chapter is viewed through the lens of how the non-genomic and genomic actions of aldosterone are linked in cardiovascular disease. Specifically, regulation of sodium flux in the myocardium has an important role in pathogenesis of cardiac arrhythmia. Since there are now recognized gender differences in cardiovascular disease, we also include preliminary studies to investigate the interaction of sex steroid hormones with the ligand binding pocket of the mineralocorticoid receptor. Overall, we aim to showcase how the non-genomic effects of aldosterone potentially modulate the genomic effects and represent additional targets for intervention.

Видовые особенности негеномной реакции главных клеток собирательных трубок почек крыс и мышей на альдостерон

We have previously shown the fast nongenomic effect of aldosterone on intracellular sodium ([Na+]i) in the principal cells of rat kidney cortical collecting duct (CCD) in low sodium outer medium (14 mM NaCl). The method of fluorescence microscopy with the intracellular dye Sodium Green was used to study the rate of [Na+]i changes in response to external sodium shift (from 137 to 14 mM ) in Wistar rat and C57bl/6 mouse principal cells. In the presence of aldosterone (10 nM), the level of intracellular sodium in the rat principal cells was higher than in control at the low sodium medium (14 mM NaCl) (р˂0.05). In the principal cells of the mice kidney CCD, the response to a sharp change in the sodium level in the outer medium was significantly faster than we have found in rat, and the nongenomic response to aldosterone (10 nM) was weaker than in rats (р˂0.05). The data obtained for the first time demonstrated the differences in the fast nongenomic aldosterone effects in the principal cells of rat and mice CCD on intracellular sodium balance.

Nongenomic glucocorticoid effects and their mechanisms of action in vertebrates.

Glucocorticoids (GC) act on multiple organ systems to regulate a variety of physiological processes in vertebrates. Due to their immunosuppressive and anti-inflammatory actions, glucocorticoids are an attractive target for pharmaceutical development. Accordingly, they are one of the most widely prescribed classes of therapeutics. Through the classical mechanism of steroid action, glucocorticoids are thought to mainly affect gene transcription, both in a stimulatory and suppressive fashion, regulating de novo protein synthesis that subsequently leads to the physiological response. However, over the past three decades multiple lines of evidence demonstrate that glucocorticoids may work through rapid, nonclassical mechanisms that do not require alterations in gene transcription or translation. This review assimilates evidence across the vertebrate taxa on the diversity of nongenomic actions of glucocorticoids and the membrane-associated cellular mechanisms that may underlie rapid glucocorticoid responses to include potential binding sites characterized to date.

The Involvement of the ERK Pathway in the Activation of the cAMP Response-Element-Binding Protein by Thyroxine in TT Cells

It has been demonstrated that thyroxine stimulates calcitonin (CT) secretion from TT cells (a model human thyroid C cells) via the cAMP-dependent protein kinase A (PKA) pathway. The nongenomic effects of thyroid hormone including activation of cAMP-dependent protein kinase and mitogen-activated protein kinase (MAPK) pathway have also been reported in TT cells. Therefore, thyroid hormones may regulate the phosphorylation of cAMP response element-binding protein (CREB) related to the MAPK pathway, but further work is needed to confirm this possibility. TT cells, were incubated in medium containing the vehicle or thyroxine. The levels of intracellular total-extracellular signal-regulated kinases (T-ERK1/2) and phospho- ERK1/2 (P-ERK1/2) were measured. The thyroxine effects on CT secretion were examined through the cAMP-dependent PKA with ERK pathways from TT cells. TT cells were treated by vehicle, thyroxine plus KT5720 (a PKA inhibitor) or U0126 (a MAP kinase inhibitor). The amount and localization of P-CREB and P-ERK were analyzed by immunofluorescence. The results indicated that thyroxine increased nuclear P-CREB expression and intracellular levels of T-ERK1/2 and P-ERK1/2 and those effects were inhibited by KT5720 and U0126. These results suggested that the thyroxine stimulates CREB phosphorylation from TT cells via the expression of P-ERK.

Glucocorticoid receptor in ayu (Plecoglossus altivelis): Genomic and non-genomic effects on monocytes/macrophages function

The glucocorticoid receptor (GR) is an important feedback regulator of the hypothalamic-pituitary-interrenal (HPI) axis. However, there are a limited number of studies focused on host-pathogen interactions in which an association between GR and immune response has been evaluated in monocytes/macrophages (MO/MФ) after being challenged with highly pathogenic bacteria. Here, we cloned the cDNA sequence of the glucocorticoid receptor (PaGR) gene from ayu fish. The PaGR transcript was expressed in all tissues, and changes in expression were observed in immune tissues and MO/MФ after live Vibrio anguillarum infection. Subsequently, PaGR was expressed and purified to prepare anti-PaGR antibodies. We analyzed the subcellular localization of PaGR. PaGR was expressed not only in the intracellular space but also in the plasma membrane. PaGR activation decreased the expression of pro-inflammatory cytokines and increased the expression of anti-inflammatory cytokines. However, PaGR activation suppressed the phagocytosis activity of V. anguillarum-infected ayu MO/MФ via a non-genomic pathway. Interestingly, PaGR activation could enhance MO/MФ bacterial killing capability and apoptosis. Therefore, PaGR may modulate the immune response in ayu MO/MФ by genomic and non-genomic pathways.

Endocrine disruption through membrane estrogen receptors and novel pathways leading to rapid toxicological and epigenetic effects

Estrogen binding to estrogen receptors (ESR) triggers signaling cascades within cells. Historically, a major emphasis has been characterizing estrogen-induced genomic actions resulting from binding to nuclear estrogen receptor 1 (nESR1). However, recent evidence indicates the first receptors estrogens encounter as they enter a cell, membrane ESR1 (mESR1), also play crucial roles. Membrane and nuclear ESR are derived from the same transcripts but the former are directed to the membrane via palmitoylation. Binding and activation of mESR1 leads to rapid fluctuations in cAMP and Ca+2 and stimulation of protein kinase pathways. Endocrine disrupting chemicals (EDC) that mimic 17β-estradiol can signal through mESR1 and elicit non-genomic effects. Most current EDC studies have focused on genomic actions via nESR1. However, increasing number of studies have begun to examine potential EDC effects mediated through mESR1, and some EDC might have higher potency for signaling through mESR1 than nESR1. The notion that such chemicals might also affect mESR1 signaling via palmitoylation and depalmitoylation pathways has also begun to gain currency. Recent development of transgenic mice that lack either mESR1 or nESR1, while retaining functional ESR1 in the other compartment, will allow more precise in vivo approaches to determine EDC effects through nESR1 and/or mESR1. It is increasingly becoming apparent in this quickly evolving field that EDC directly affect mESR and estrogen signaling, but such chemicals can also affect proportion of ESR reaching the membrane. Future EDC studies should be designed to consider the full range of effects through mESR alone and in combination with nESR.

Activation of GPER suppresses the malignancy of osteosarcoma cells via down regulation of IL-6 and IL-8

Estrogenic signals can regulate the progression of osteosarcoma (OS) via classic estrogen receptor α/β (ERα/β). G protein-coupled estrogen receptor (GPER) can mediate the non-genomic effects of estrogen and regulate the progression of various cancers. Our present study revealed that the expression of GPER in OS cells and tissues was lower than that in their corresponding controls. Activation of GPER via its specific agonist G-1 can decrease the proliferation, migration, and invasion of OS cells. By screening the expression of cytokines involved in the progression of OS, we found that activation of GPER can inhibit the expression of interleukin-6 (IL-6) and IL-8 in OS cells. Recombinant IL-6 (rIL-6) or rIL-8 can attenuate G-1 suppressed migration of OS cells. Mechanically, activation of GPER can rapidly decease the phosphorylation and nuclear translocation of NF-κB in OS cells. While over expression of p65 significantly attenuated G-1 induced down regulation of IL-6/IL-8. Further, G-1 can decrease the activation of p38-MAPK, which can further shorten the half-life of IL-8 mRNA. Collectively, we revealed that GPER can suppress the migration and invasion of OS cells via inhibition of IL-6 and IL-8. It suggested that GPER might be a potential therapy target for OS treatment.

Vitamin D, muscle recovery, sarcopenia, cachexia, and muscle atrophy.

The relevance of vitamin D to skeletal muscle metabolism has been highlighted in recent years. The interest arises from the important findings of studies demonstrating multiple effects of vitamin D on this tissue, which can be divided into genomic (direct effects) and non-genomic effects (indirect effects). Another important aspect to be considered in the study of vitamin D and muscle fiber metabolism is related to different expression of vitamin D receptor (VDR), which varies in muscle tissue depending on age, sex, and pathology. The correlation between low circulating levels of vitamin D and muscle metabolism disorders is documented in various contexts, including muscle recovery, atrophy, sarcopenia, and cachexia. The aim of this review was to analyze recent results of both in vitro and in vivo studies to address the relationship between vitamin D and skeletal muscle biology. The words muscle atrophy, muscle hypertrophy, sarcopenia, and cachexia were crossed over with vitamin D in a Pubmed search. All original contributions, along with reviews on the topic, were included, and no publications in the past 10 y were discarded. The papers retrieved different topics such as vitamin D in skeletal muscle; vitamin D in circulation; vitamin D, sarcopenia, and muscle atrophy; vitamin D and cachexia; and vitamin D and muscle recovery.

Role of the central nucleus of the amygdala in regulating the nongenomic effect of aldosterone on sodium intake in rat nucleus tractus solitarius

To reveal the nongenomic effect of aldosterone on the regulation of sodium intake in the nucleus tractus solitarius (NTS) and the role of central nucleus of the amygdala (CeA) in regulating this effect. Adult male SD rats were divided into four groups and underwent operations to induce bilateral CeA electrolytic lesions (400 μA, 25 s; n=28), bilateral sham CeA lesions (n=28), unilateral CeA lesions (n=28), or unilateral sham CeA lesions (n=26). After 3 days of recovery, the rats received implantation of a stainless steel 23-gauge cannula wih two tubes into the NTS followed by a recovery period of 7 days. The rats in each group were then divided into two subgroups for microinjection of aldosterone (50 ng/μL) or control solution in the NTS, and the cumulative intake within 30 min of 0.3 mol/L NaCl solution was recorded for each rat. Bilateral CeA lesions (3 days) eliminated the increased 0.3 mol/L NaCl intake induced by aldosterone microinjected into the NTS (0.3±0.04 mL in CeA lesion group vs 1.3±0.3 mL in sham lesion group). Unilateral CeA lesion (3 days) reduced aldosterone-induced increase of NaCl intake in the first 15 min (P < 0.05) but not in 15-30 min (P > 0.05). In rats with sham lesions, aldosterone (50 ng/μL) still induced a significant increase in NaCl intake[1.3±0.3 mL vs 0.25±0.02 mL in the control group; F (3, 224)=24.0, P < 0.05]. The regulation of sodium intake by aldosterone is subjected to descending facilitatory modulation by the bilateral CeA, and CeA integrity is essential for aldosterone to execute the nongenomic effect in regulating rapid sodium intake.