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1.
Free Radic Biol Med ; 222: 229-243, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38906233

RESUMEN

Ferroptosis is a form of iron-dependent cell death that has attracted significant attention for its potential role in numerous diseases. Targeted inhibition of ferroptosis could be of potential use in treating diseases: such as drug induced liver injury (DILI). Ferroptosis can be antagonized by the xCT/GSH/GPX4, FSP1/CoQ10, DHODH/CoQ10, GCH1/BH4, and NRF2 pathways. Identifying novel anti-ferroptosis pathways will further promote our understanding of the biological nature of ferroptosis and help discover new drugs targeting ferroptosis related human diseases. In this study, we identified the clinically used drug mifepristone (RU486) as a novel ferroptosis inhibitor. Mechanistically, RU486 inhibits ferroptosis by inducing GSH synthesis pathway, which supplies GSH for glutathione-S-transferase (GST) mediated 4-HNE detoxification. Furthermore, RU486 induced RLIP76 and MRP1 export 4-HNE conjugate contributes to its anti-ferroptosis activity. Interestingly, RU486 induced GSH/GSTs/RLIP76&MRP1 anti-ferroptosis pathway acts independent of classic anti-ferroptosis systems: including xCT/GSH/GPX4, FSP1, DHODH, GCH1, SCD1 and FTH1. Moreover, NRF2 was identified to be important for RU486's anti-ferroptosis activity by inducing downstream gene expression. Importantly, in mouse model, RU486 showed strong protection effect on acetaminophen (APAP)-induced acute liver injury, evidenced by decreased ALT, AST level and histological recovery after APAP treatment. Interestingly, RU486 also decreased oxidative markers, including 4-HNE and MDA, and induced NRF2 activation as well as GSTs, MRP1 expression. Together, these data suggest NRF2/GSH/GST/RLIP76&MRP1 mediated detoxification pathway as an important independent anti-ferroptosis pathway act both in vitro and in vivo.


Asunto(s)
Acetaminofén , Enfermedad Hepática Inducida por Sustancias y Drogas , Ferroptosis , Glutatión Transferasa , Glutatión , Mifepristona , Factor 2 Relacionado con NF-E2 , Animales , Ferroptosis/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Mifepristona/farmacología , Acetaminofén/efectos adversos , Acetaminofén/toxicidad , Ratones , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Glutatión/metabolismo , Glutatión Transferasa/metabolismo , Glutatión Transferasa/genética , Humanos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Transducción de Señal/efectos de los fármacos , Ratones Endogámicos C57BL , Masculino , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Proteínas Activadoras de GTPasa
2.
Physiol Behav ; 283: 114609, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38851441

RESUMEN

The neuropeptide kisspeptin (Kiss) is crucial in regulating the hypothalamic-pituitary-gonadal axis. It is produced by two main groups of neurons in the hypothalamus: the rostral periventricular region around the third ventricle and the arcuate nucleus. Kiss is the peptide product of the KiSS-1 gene and serves as the endogenous agonist for the GPR54 receptor. The Kiss/GPR54 system functions as a critical regulator of the reproductive system. Thus, we examined the effect of intracerebroventricular administration of 3 µg of Kiss to the right lateral ventricle of ovariectomized rats primed with a dose of 5 µg subcutaneous (sc) of estradiol benzoate (EB). Kiss treatment increased the lordosis quotient at all times tested. However, the lordosis reflex score was comparatively lower yet still significant compared to the control group. To investigate receptor specificity and downstream mechanisms on lordosis, we infused 10 µg of GPR54 receptor antagonist, Kiss-234, 5 µg of the progestin receptor antagonist, RU486, or 3 µg of antide, a gonadotropin-releasing hormone-1 (GnRH-1) receptor antagonist, to the right lateral ventricle 30 min before an infusion of 3 µg of Kiss. Results demonstrated a significant reduction in the facilitation of lordosis behavior by Kiss at 60 and 120 min when Kiss-234, RU486, or antide were administered. These findings suggest that Kiss stimulates lordosis expression by activating GPR54 receptors on GnRH neurons and that Kiss/GPR54 system is an essential intermediary by which progesterone activates GnRH.


Asunto(s)
Estradiol , Kisspeptinas , Receptores LHRH , Receptores de Progesterona , Conducta Sexual Animal , Animales , Kisspeptinas/farmacología , Kisspeptinas/metabolismo , Femenino , Conducta Sexual Animal/efectos de los fármacos , Conducta Sexual Animal/fisiología , Receptores LHRH/antagonistas & inhibidores , Receptores LHRH/metabolismo , Ratas , Estradiol/farmacología , Estradiol/análogos & derivados , Receptores de Progesterona/metabolismo , Receptores de Progesterona/efectos de los fármacos , Receptores de Progesterona/antagonistas & inhibidores , Ovariectomía , Ratas Wistar , Progesterona/farmacología , Antagonistas de Hormonas/farmacología , Postura/fisiología , Receptores de Kisspeptina-1/metabolismo , Mifepristona/farmacología
3.
J Reprod Immunol ; 163: 104244, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38555747

RESUMEN

Implantation and maintenance of pregnancy involve intricate immunological processes that enable the developing fetus to coexist with the maternal immune system. Progesterone, a critical hormone during pregnancy, is known to promote immune tolerance and prevent preterm labor. However, the mechanism by which progesterone mediates these effects remains unclear. In this study, we investigated the role of the non-classical progesterone receptor membrane component 1 (PGRMC1) in progesterone signaling at the maternal-fetal interface. Using JEG3 cells, a trophoblast model cell line, we observed that progesterone stimulation increased the expression of human leukocyte antigen-C (HLA-C) and HLA-G, key molecules involved in immune tolerance. We also found that progesterone upregulated the expression of the transcription factor ELF3, which is known to regulate trophoblast-specific HLA-C expression. Interestingly, JEG3 cells lacked expression of classical progesterone receptors (PRs) but exhibited high expression of PGRMC1, a finding we confirmed in primary trophoblasts by mining sc-RNA seq data from human placenta. To investigate the role of PGRMC1 in progesterone signaling, we used CRISPR/Cas9 technology to knockout PGRMC1 in JEG3 cells. PGRMC1-deficient cells showed a diminished response to progesterone stimulation. Furthermore, we found that the progesterone antagonist RU486 inhibited ELF3 expression in a PGRMC1-dependent manner, suggesting that RU486 acts as a progesterone antagonist by competing for receptor binding. Additionally, we found that RU486 inhibited cell invasion, an important process for successful pregnancy, and this inhibitory effect was dependent on PGRMC1. Our findings highlight the crucial role of PGRMC1 in mediating the immunoregulatory effects of progesterone at the maternal-fetal interface.


Asunto(s)
Proteínas de la Membrana , Progesterona , Receptores de Progesterona , Trofoblastos , Humanos , Receptores de Progesterona/metabolismo , Femenino , Embarazo , Progesterona/metabolismo , Progesterona/farmacología , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Trofoblastos/metabolismo , Trofoblastos/inmunología , Placenta/inmunología , Placenta/metabolismo , Transducción de Señal/inmunología , Intercambio Materno-Fetal/inmunología , Implantación del Embrión/inmunología
4.
G3 (Bethesda) ; 14(5)2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38409337

RESUMEN

Robust genetic systems to control the expression of transgenes in a spatial and temporal manner are a valuable asset for researchers. The GeneSwitch system induced by the drug RU486 has gained widespread use in the Drosophila community. However, some concerns were raised as negative effects were seen depending on the stock, transgene, stage, and tissue under study. Here, we characterized the adverse effects triggered by activating the GeneSwitch system in adult muscles using the MHC-GS-GAL4 driver. When a control, mock UAS-RNAi transgene was induced by feeding adult flies with RU486, we found that the overall muscle structure, including myofibrils and mitochondrial shape, was significantly disrupted and led to a significant reduction in the lifespan. Remarkably, lifespan was even shorter when 2 copies of the driver were used even without the mock UAS-RNAi transgene. Thus, researchers should be cautious when interpreting the results given the adverse effects we found when inducing RU486-dependent MHC-GS-GAL4 in adult muscles. To account for the impact of these effects we recommend adjusting the dose of RU486, setting up additional control groups, such as a mock UAS-RNAi transgene, as comparing the phenotypes between RU486-treated and untreated animals could be insufficient.


Asunto(s)
Mifepristona , Transgenes , Animales , Mifepristona/farmacología , Músculos/metabolismo , Músculos/efectos de los fármacos , Proteínas de Drosophila/genética , Animales Modificados Genéticamente , Interferencia de ARN , Drosophila/genética , Drosophila/efectos de los fármacos , Drosophila melanogaster/genética , Drosophila melanogaster/efectos de los fármacos , Fenotipo , Longevidad/efectos de los fármacos , Longevidad/genética
5.
Linacre Q ; 90(4): 395-407, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37969420

RESUMEN

The safety and efficacy of mifepristone antagonization with progesterone to avert medication abortion, also known as abortion pill rescue, is a subject of vigorous debate. Two prominent medical associations have taken positions that either entirely reject or fully support its use. This scoping review aimed to gain insight into the safety and efficacy of its use. Analysis of 16 studies showed that the continuing pregnancy rate after ingesting mifepristone alone is ≦25 percent for gestational ages ≦49 days. Analysis of four studies showed that two-thirds of the women who changed their minds and received progesterone after initiating their medication abortion with mifepristone could safely continue their pregnancies. There is no increased maternal or fetal risk from using bioidentical progesterone in early pregnancy. If a woman has already taken mifepristone for her medication abortion and then changes her mind, timely supplementation with progesterone may allow her pregnancy to continue. The conclusion that mifepristone antagonization with progesterone is a safe and effective treatment has implications for medication abortion informed consent. Summary: Two-thirds of the women who changed their minds and received progesterone after initiating their medication abortion with mifepristone could safely continue their pregnancies. If a woman has already taken mifepristone for her medication abortion and then changes her mind, timely supplementation with progesterone may allow her pregnancy to continue. Physicians should disclose this treatment option to their patients at the time of informed consent.

6.
Eur J Med Res ; 28(1): 303, 2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37644600

RESUMEN

BACKGROUND: We sought to determine the extent to which cortisol suppressed innate and T cell-mediated cytokine production and whether it could be involved in reducing peripheral cytokine production following subarachnoid haemorrhage (SAH). METHODS: Whole blood from healthy controls, patients with SAH and healthy volunteers was stimulated with lipopolysaccharide (LPS), to stimulate innate immunity, or phytohaemagglutinin (PHA), to stimulate T cell-mediated immunity. Varying concentrations of cortisol were included, with or without the cortisol antagonist RU486. Concentration of interleukin-6 (IL-6), IL-1ß and tumour necrosis factor-alpha) TNFα were determined as a measure of innate immunity. IL-6, IL-17 (interferon gamma) IFNƔ and IL-17 were determined as an indicator of T cell-mediated immunity. RESULTS: Suppression of innate responses to LPS was apparent in whole blood from SAH patients, relative to healthy controls, and TNFα production was inversely correlated with plasma cortisol concentration. Cytokine production in whole blood from healthy volunteers was inhibited by cortisol concentrations from 0.33 µM, or 1 µM and above, and these responses were effectively reversed by the cortisol antagonist RU-486. In SAH patients, RU-486 reversed suppression of innate TNF-α and IL-6 responses, but not IL-1ß or T cell-mediated responses. CONCLUSION: These data suggest that cortisol may play a role in reducing innate, but not T cell-mediated immune responses in patients with injuries such as SAH and that cortisol antagonists could be effective in boosting early innate responses.


Asunto(s)
Hidrocortisona , Hemorragia Subaracnoidea , Humanos , Interleucina-17 , Interleucina-6 , Lipopolisacáridos/farmacología , Mifepristona , Factor de Necrosis Tumoral alfa , Terapia de Inmunosupresión , Interferón gamma
7.
Physiol Rep ; 11(11): e15745, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37280729

RESUMEN

This study investigated whether muscle contraction induces expression of regulated in development and DNA damage 1 (REDD1), a potent inhibitor of mTORC1, in mice muscle. Gastrocnemius muscle was unilaterally and isometrically contracted with electrical stimulation, and changes in muscle protein synthesis, mTORC1 signaling phosphorylation, and REDD1 protein, and mRNA were measured at time points of 0, 3, 6, 12, and 24 h after the contraction. At time point 0 and 3 h, muscle protein synthesis was blunted by the contraction, accompanied by a decrease in phosphorylation of 4E-BP1 at time point 0 h, suggesting suppression of mTORC1 was involved in blunting of muscle protein synthesis during and shortly after the contraction. REDD1 protein was not increased in the contracted muscle at these time points, but at time point 3 h, both REDD1 protein and mRNA were increased in the contralateral non-contracted muscle. The induction of REDD1 expression in the non-contracted muscle was attenuated by RU-486, an antagonist of the glucocorticoid receptor, suggesting that glucocorticoids are involved in this process. These findings suggest that muscle contraction induces temporal anabolic resistance in non-contracted muscle, potentially increasing the availability of amino acids for contracted muscle, allowing for the synthesis of muscle protein.


Asunto(s)
Glucocorticoides , Serina-Treonina Quinasas TOR , Ratones , Animales , Glucocorticoides/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Contracción Isométrica , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Músculo Esquelético/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Fosforilación/fisiología , Proteínas Musculares/metabolismo
8.
Biomedicines ; 11(3)2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36979886

RESUMEN

The clinical use of mifepristone for medical abortions has been established in 1987 in France and since 2000 in the United States. Mifepristone has a limited medical period that lasts <9 weeks of gestation, and the incidence of mifepristone treatment failure increases with gestation time. Mifepristone functions as an antagonist for progesterone and glucocorticoid receptors. Studies have confirmed that mifepristone treatments can directly contribute to endometrium disability by interfering with the endometrial receptivity of the embryo, thus causing decidual endometrial degeneration. However, whether mifepristone efficacy directly affects embryo survival and growth is still an open question. Some women choose to continue their pregnancy after mifepristone treatment fails, and some women express regret and seek medically unapproved mifepristone antagonization with high doses of progesterone. These unapproved treatments raise the potential risk of embryonic fatality and developmental anomalies. Accordingly, in the present study, we collected mouse blastocysts ex vivo and treated implanted blastocysts with mifepristone for 24 h. The embryos were further cultured to day 8 in vitro to finish their growth in the early somite stage, and the embryos were then collected for RNA sequencing (control n = 3, mifepristone n = 3). When we performed a gene set enrichment analysis, our data indicated that mifepristone treatment considerably altered the cellular pathways of embryos in terms of viability, proliferation, and development. The data indicated that mifepristone was involved in hallmark gene sets of protein secretion, mTORC1, fatty acid metabolism, IL-2-STAT5 signaling, adipogenesis, peroxisome, glycolysis, E2F targets, and heme metabolism. The data further revealed that mifepristone interfered with normal embryonic development. In sum, our data suggest that continuing a pregnancy after mifepristone treatment fails is inappropriate and infeasible. The results of our study reveal a high risk of fetus fatality and developmental problems when pregnancies are continued after mifepristone treatment fails.

9.
Front Endocrinol (Lausanne) ; 14: 1151873, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38260129

RESUMEN

Two adrenalectomies py -45erformed fourteen years apart notoriously alleviated insulin resistance in a female teenager with Congenital Generalized Lipoatrophy (CGL, 1988) and in a murine model of CGL (2002). Following a successful therapeutic trial with anti-glucocorticoids, we performed the first surgical procedure on an 18-year-old girl. Before surgery, the anti-glucocorticoid therapy produced a rapid and striking drop in fasting serum insulin levels (from over 400 to 7.0 mU/L) and a slower -but impressive- fall in fasting serum triglycerides from 7,400 to 220-230 mg/dL. In contrast, fasting serum glucose levels dropped more slowly, from 225-290 to 121-138 mg/dL. Two weeks following total adrenalectomy, the fasting serum glucose level was 98 mg/dL, with a corresponding serum insulin level of 10 mU/L. During an Oral Glucose Tolerance Test, the 2-hour serum glucose was 210 mg/dL, and serum insulin values during the test did not exceed 53 mU/L. In 2002, the A-ZIP/F1 hypoleptinemic mouse had its adrenal glands removed. Even though this CGL model does not respond well to leptin replacement, an infusion of recombinant leptin reduced the characteristic hypercorticosteronemia of this murine model of CGL. Adrenalectomy in this transgenic mouse improved insulin sensitivity in the liver and muscle. In summary, adrenalectomy -in both a human and a mouse case of CGL- limited adipose tissue exposure to corticosteroid action and led to a notorious metabolic improvement. On a broader scenario, given that leptin restrains the adrenal axis, the reduced leptin activity of the leptin resistance displayed by obese subjects should lead to adrenal axis overactivity. This overactivity should result in elevated serum levels of free cortisol, free fatty acids, and glycerol. In this manner, leptin resistance should lead to peripheral (adipose tissue, liver, and muscle) insulin resistance and islet beta-cell apoptosis, paving the way to Type 2 diabetes.


Asunto(s)
Diabetes Mellitus Lipoatrófica , Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Insulinas , Lipodistrofia Generalizada Congénita , Adolescente , Animales , Femenino , Humanos , Ratones , Adrenalectomía , Modelos Animales de Enfermedad , Glucosa , Leptina , Informes de Casos como Asunto
10.
Int J Neurosci ; : 1-10, 2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36469636

RESUMEN

BACKGROUND: Allopregnanolone (3α, 5α-tetrahydroprogesterone) is an inhibitory neurosteroid synthesized from progesterone via 5α-reductase activity in the brain and has anxiolytic, antidepressant, sedative, anticonvulsant, and analgesic activity. Altered levels of allopregnanolone cause anxiety, depression, premenstrual syndrome, and psychiatric disorders. Although allopregnanolone exerts most of its actions by modulating GABAA receptor, NMDA receptor, BDNF expression, and PXR activity, a recent study showed its effects are blocked by mifepristone on lordosis behavior which indicates the involvement of progestin or glucocorticoid receptors in the effects of allopregnanolone since mifepristone blocks both these receptors. However, whether these receptors are involved in acute anxiolytic or antidepressant-like effects is unknown. METHODS: Adult male Wistar rats were used to study whether the prior administration of mifepristone would alter the effects of allopregnanolone in the elevated plus maze (EPM) and forced swim test (FST) was evaluated. RESULTS: 10 mg/Kg dose of allopregnanolone increased percent open arm entries in the EPM, whereas 3 mg/Kg dose of allopregnanolone decreased percent immobility in the FST. Mifepristone administration resulted in a U-shaped response in the FST (with 1 mg/Kg, s.c., decreasing the immobility time) without significantly impacting the behavior in the EPM. In combination studies, mifepristone blocked the anxiolytic and antidepressant effects of allopregnanolone. CONCLUSION: The current study provides evidence for the first time that progestin or glucocorticoid receptors are involved in the acute anxiolytic and antidepressant effects of allopregnanolone. Understanding the mechanism of action of allopregnanolone will help us design better therapeutic strategies to treat neuropsychiatric diseases such as depression and anxiety.

11.
Molecules ; 27(21)2022 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-36364430

RESUMEN

The aim of the study was the development and validation of the UHPLC-QqQ-MS/MS method for the determination of mifepristone in human blood as well as the identification and quantification of its metabolites after self-induced pharmacological abortion. The metabolic pathway in humans was proposed after examination of an authentic casework. The fast and simple preanalytical procedure was successfully applied (pH9, tert-butyl-methyl ether). The validation parameters of the method were as follows: limit of quantification: 0.5 ng/mL; coefficients of determination: >0.999 (R2), intra- and inter-day accuracy and precision values did not exceed ± 13.2%. The recovery and matrix effect were in the range of 96.3−114.7% and from −3.0 to 14.7%, respectively. Toxicological analysis of the mother's blood (collected the day after the pregnancy termination) revealed the presence of five compounds: mifepristone (557.4 ng/mL), N-desmethyl-mifepristone (638.7 ng/mL), 22-OH-mifepristone (176.9 ng/mL), N,N-didesmethyl-mifepristone (144.5 ng/mL) and N-desmethyl-hydroxy-mifepristone (qualitatively). To our knowledge, the study presented in this paper is the first report on the concentrations of mifepristone and its metabolites in maternal blood samples after performing a self-induced abortion. The established UHPLC-QqQ-MS/MS method is suitable for forensic toxicological analysis as well as in terms of clinical toxicology in future investigations (examination of pharmacokinetics, bioavailability and metabolism of RU-486).


Asunto(s)
Aborto Inducido , Mifepristona , Embarazo , Femenino , Humanos , Espectrometría de Masas en Tándem , Aborto Inducido/métodos
12.
Pharmacol Res ; 185: 106521, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36272641

RESUMEN

The melanocortinergic neural circuit, known for its influence on energy expenditure and feeding behavior, also plays a role in stress and stress-induced psychiatric disorders, including anxiety and depression. The major contribution is given by the melanocortin-4 receptor (MC4R) subtype, highly expressed in brain regions involved in the control of stress responses. Furthermore, the MC4R appears to profoundly affect the activity of the hypothalamic-pituitary-adrenal (HPA) axis, and it has been also highlighted a functional and anatomical interaction with the corticotropin-releasing factor (CRF), an important mediator of stress and stress-related behaviors. The MC4R agonists seem to exacerbate stress-inducing anxiety- and depressive-like behavior, while MC4R antagonists have been demonstrated to mitigate such disorders, as shown in several preclinical behavioral tests. The evidence collected in the present review suggests that the melanocortin system, through the MC4R, could possibly modulate behavioral responses to stress, suggesting the use of MC4R antagonists as a possible novel treatment for anxiety and depression induced by stress.


Asunto(s)
Melanocortinas , Sistema Hipófiso-Suprarrenal , Humanos , Ansiedad/tratamiento farmacológico , Sistema Hipotálamo-Hipofisario , Estrés Fisiológico
13.
Artículo en Inglés | MEDLINE | ID: mdl-36169060

RESUMEN

The gastrointestinal system of fish reacts rapidly to food deprivation. The relative masses of digestive organs and activities of digestive enzymes decrease within days of fasting. This is believed to be an energy-conserving strategy as the metabolic cost of maintaining digestive capacity is high. Cortisol is known for its role in energy mobilization following stress exposure, and prolonged elevated cortisol levels have been shown to reduce growth rates in fish. Fish experiencing chronic cortisol elevations show structural changes to their digestive tissues and overall reductions in relative digestive tissue masses. In fish fasting for prolonged periods, circulating cortisol levels have been reported to be downregulated, upregulated, or unchanged compared to feeding fish. This study aimed to investigate if RU486 and spironolactone, antagonists of the glucocorticoid receptor (GR), and mineralocorticoid receptor (MR), respectively, alone or in combination affect circulating cortisol levels during prolonged starvation. In addition, we tested the effects of blocking GR and MR, on the down-regulation of relative digestive tissue mass during starvation, and its effects on weight loss. Three treatment groups of rainbow trout were intraperitoneally implanted with either GR, MR, or GR and MR blockers. A fourth group was implanted with cortisol, while a fifth group served as a control. All treatment groups were sampled over a course of four weeks of food deprivation and compared against each other and fed control fish at day 0 of the trial. Starvation for 2 weeks and longer significantly increased circulating cortisol levels in all groups except for the group implanted with GR and MR antagonists. Loss of body mass occurred most rapidly during the first week of starvation. Spironolactone treatment resulted in significantly reduced loss of mass during the first week, however, over the following weeks, no differences in mass loss were observed in the groups implanted with blockers, while cortisol-treated fish showed the highest decrease in body mass over time. Relative digestive tissue mass decreased in all groups but apparently, the fasting-induced elevation in plasma cortisol levels did not affect the relative weight loss of digestive tissues as no differences were observed between control fish and GR + MR antagonist treated fish. Very high cortisol levels caused by cortisol treatment however caused a faster decrease in the relative mass of some digestive organs, particularly the stomach.


Asunto(s)
Oncorhynchus mykiss , Receptores de Mineralocorticoides , Animales , Ayuno , Glucocorticoides/metabolismo , Hidrocortisona , Mifepristona/farmacología , Antagonistas de Receptores de Mineralocorticoides/metabolismo , Antagonistas de Receptores de Mineralocorticoides/farmacología , Oncorhynchus mykiss/fisiología , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , Espironolactona/metabolismo , Espironolactona/farmacología , Pérdida de Peso
14.
Artículo en Inglés | MEDLINE | ID: mdl-35886217

RESUMEN

BACKGROUND: Mifepristone (RU-486) has been approved for abortion in Taiwan since 2000. Mifepristone was the first non-addictive medicine to be classified as a schedule IV controlled drug. As a case of the "misuse" of "misuse of drugs laws," the policy and consequences of mifepristone-assisted abortion for pregnant women could be compared with those of illicit drug use for drug addicts. METHODS: The rule-making process of mifepristone regulation was analyzed from various aspects of legitimacy, social stigma, women's human rights, and access to health care. RESULTS AND DISCUSSION: The restriction policy on mifepristone regulation in Taiwan has raised concerns over the legitimacy of listing a non-addictive substance as a controlled drug, which may produce stigma and negatively affect women's reproductive and privacy rights. Such a restriction policy and social stigma may lead to the unwillingness of pregnant women to utilize safe abortion services. Under the threat of the COVID-19 pandemic, the US FDA's action on mifepristone prescription and dispensing reminds us it is time to consider a change of policy. CONCLUSIONS: Listing mifepristone as a controlled drug could impede the acceptability and accessibility of safe mifepristone use and violates women's right to health care.


Asunto(s)
Mifepristona , Política Pública , Aborto Inducido/métodos , COVID-19/epidemiología , Femenino , Humanos , Mifepristona/uso terapéutico , Pandemias , Embarazo , Salud de la Mujer , Tratamiento Farmacológico de COVID-19
15.
Steroids ; 184: 109058, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35679911

RESUMEN

Mifepristone is a non-selective progesterone (PR), glucocorticoid (GR), and androgen receptor (AR) antagonist with antidepressant and anxiolytic effects. The dose and duration of mifepristone administration vary in rodent preclinical studies to evaluate depression-like and anxiety-like behavior. This review summarizes the findings so far and attempts to reconcile some of the differences in the results. While a few studies assessed basal depression- and anxiety-like behavior, several studies have used mifepristone in conjunction with stress, corticosterone/dexamethasone (after adrenalectomy), or progesterone administration. The effect of mifepristone on depression-like behavior appears to depend not only on the dose and duration of administration but also on the intensity or type of stress. In addition, the anxiolytic effects may depend on the species and strain of the experimental animals. More reports assess antidepressant-like or anxiolytic-like effects following acute than chronic administration. These effects are dependent on the paradigms and the nature of stressors. Most mifepristone studies implicate the role of GRs, yet only two reports have confirmed its role using a genetic approach, whereas none implicate the role of PRs/ARs. There are several novel selective GR antagonists whose effects on depression- and anxiety-like behavior are yet to be studied. Future studies could aim to confirm the role of GRs and evaluate the contribution of PRs/ARs to the effects of mifepristone. Such studies will contribute to a better understanding of depression, anxiety, and other mood disorders and develop novel strategies, particularly for treatment-resistant conditions.


Asunto(s)
Ansiolíticos , Mifepristona , Animales , Ansiolíticos/farmacología , Ansiolíticos/uso terapéutico , Antidepresivos/farmacología , Antidepresivos/uso terapéutico , Ansiedad/tratamiento farmacológico , Depresión/tratamiento farmacológico , Glucocorticoides , Mifepristona/farmacología , Progesterona , Receptores de Glucocorticoides , Roedores
16.
Int J Mol Sci ; 23(9)2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35563258

RESUMEN

Preterm birth (PTB) represents 15 million births every year worldwide and is frequently associated with maternal/fetal infections and inflammation, inducing neuroinflammation. This neuroinflammation is mediated by microglial cells, which are brain-resident macrophages that release cytotoxic molecules that block oligodendrocyte differentiation, leading to hypomyelination. Some preterm survivors can face lifetime motor and/or cognitive disabilities linked to periventricular white matter injuries (PWMIs). There is currently no recommendation concerning the mode of delivery in the case of PTB and its impact on brain development. Many animal models of induced-PTB based on LPS injections exist, but with a low survival rate. There is a lack of information regarding clinically used pharmacological substances to induce PTB and their consequences on brain development. Mifepristone (RU-486) is a drug used clinically to induce preterm labor. This study aims to elaborate and characterize a new model of induced-PTB and PWMIs by the gestational injection of RU-486 and the perinatal injection of pups with IL-1beta. A RU-486 single subcutaneous (s.c.) injection at embryonic day (E)18.5 induced PTB at E19.5 in pregnant OF1 mice. All pups were born alive and were adopted directly after birth. IL-1beta was injected intraperitoneally from postnatal day (P)1 to P5. Animals exposed to both RU-486 and IL-1beta demonstrated microglial reactivity and subsequent PWMIs. In conclusion, the s.c. administration of RU-486 induced labor within 24 h with a high survival rate for pups. In the context of perinatal inflammation, RU-486 labor induction significantly decreases microglial reactivity in vivo but did not prevent subsequent PWMIs.


Asunto(s)
Microglía , Nacimiento Prematuro , Animales , Animales Recién Nacidos , Femenino , Humanos , Inflamación , Lipopolisacáridos/toxicidad , Ratones , Mifepristona/farmacología , Embarazo
17.
Brain Res ; 1782: 147833, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35189098

RESUMEN

Several brain structures responsible for controlling stress responses reach maturity during adolescence. Therefore, acute or chronic stress in prepuberty may negatively affect stress responses as well as behavior in adulthood. The hypothalamus-pituitary-adrenal axis (HPA) is part of the stress system whose inhibitory control is regulated by glucocorticoids through mineralocorticoid (MR) and glucocorticoid (GR) receptors. In this study, we aimed to determine whether MR or GR blockade after stress in adolescence prevents changes in exploratory behavior and HPA axis control in adult female rats. Adolescent female rats (26 days old) were submitted to one or seven daily restraint sessions followed by administration of MR (spironolactone) or GR (RU-486) antagonists. At 60 days old, animals were evaluated in the elevated plus maze and at 61 days old rats were subjected to acute stress to evaluate the HPA response. The chronic restraint in the adolescence induced an anxiogenic effect in the adult animals that was reverted by either MR or GR antagonist. In the same way chronic stress reduced the HPA axis activity by blunted corticosterone (CORT) secretion and decreased the activation of Corticotropin Releasing Hormone (CRH) neurons in the paraventricular nucleus. The post-stress blocking of GR independently restored the CORT secretion without effect on central activation. The acute stress in the adolescence had minor enduring effects. We concluded that the use of RU-486 and spironolactone after stress in the early adolescence can improve behavioral changes induced by stress whereas RU-486 only showed effect on the HPA axis response in adulthood.


Asunto(s)
Ansiedad , Sistema Hipotálamo-Hipofisario , Antagonistas de Receptores de Mineralocorticoides , Sistema Hipófiso-Suprarrenal , Receptores de Glucocorticoides , Animales , Corticosterona/farmacología , Hormona Liberadora de Corticotropina/metabolismo , Femenino , Glucocorticoides/farmacología , Mifepristona/farmacología , Antagonistas de Receptores de Mineralocorticoides/farmacología , Ratas , Receptores de Glucocorticoides/antagonistas & inhibidores , Espironolactona/farmacología , Estrés Psicológico
19.
Artículo en Inglés | MEDLINE | ID: mdl-34831795

RESUMEN

The limitations caused by the spread of the SARS-CoV2 virus have had repercussions on the voluntary termination of pregnancy. During the pandemic, Italy issued updated guidelines regarding voluntary termination of pregnancy by means of mifepristone and prostaglandin. This included news concerning the time limit and location in which this procedure could be accessed: updates partially recognize women's needs, and they are into line with the European parliament's recent exhortations. However, these updates do not change the previously provided responsibilities that lie with doctors. This article aimed to compare regulations concerning medical abortion in Italy and other countries, with a focus on recent Italian updates in the context of pandemic.


Asunto(s)
Aborto Inducido , COVID-19 , Femenino , Humanos , Italia/epidemiología , Pandemias , Embarazo , ARN Viral , SARS-CoV-2
20.
Mol Cell Biochem ; 476(12): 4471-4485, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34491525

RESUMEN

Glucocorticoids (GCs) regulate astrocyte function, while glutamine synthetase (GS), an enzyme highly expressed in astrocytes, is one of the most remarkable GCs-induced genes. GCs mediate their effects through their cognate glucocorticoid receptor (GRα and GRß isoforms); however, the mechanism via which these isoforms regulate GS activity in astrocytes remains unknown. We used dexamethasone (DEX), a classical GRα/GRß agonist, RU486, which is a specific GRß ligand, and Compound A, a known "dissociated" ligand, to delineate the mechanism via which GR modulates GS activity. Aged Mouse Cerebral Hemisphere astrocytes were treated with DEX (1 µM), RU486 (1 nM-1 µM) or compound A (10 µM), alone or in combination with DEX. GS activity and expression, GR isoforms (mRNA and protein levels), and GRα subcellular trafficking were measured. DEX increased GS activity in parallel with GRα nuclear translocation. RU486 increased GS activity in absence of GRα nuclear translocation implicating thus a role of GRß-mediated mechanism compound A had no effect on GS activity implicating a GRα-GRE-mediated mechanism. None of the compounds affected whole-cell GRα protein content. DEX reduced GRα and GRß mRNA levels, while RU486 increased GRß gene expression. We provide evidence that GS activity, in astrocytes, is regulated via GRα- and GRß-mediated pathways with important implications in pathological conditions in which astrocytes are involved.


Asunto(s)
Astrocitos/metabolismo , Cerebro/metabolismo , Glutamato-Amoníaco Ligasa/metabolismo , Receptores de Glucocorticoides/metabolismo , Acetatos/farmacología , Factores de Edad , Animales , Antiinflamatorios/farmacología , Antiinflamatorios no Esteroideos/farmacología , Astrocitos/efectos de los fármacos , Células Cultivadas , Cerebro/efectos de los fármacos , Cerebro/patología , Dexametasona/farmacología , Antagonistas de Hormonas/farmacología , Ratones , Mifepristona/farmacología , Tiramina/análogos & derivados , Tiramina/farmacología
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