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1.
F S Sci ; 4(4): 286-293, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37516276

RESUMO

OBJECTIVE: To study if a pituitary or ovarian defect contributes to subfertility of the female Nsmf knockout (KO) mouse, an animal model of the hypogonadotropic hypogonadism gene NSMF. DESIGN: Analysis of hypothalamic, pituitary and ovarian gene expression at baseline, serum gonadotropin levels before and after gonadotropin-releasing hormone (GnRH) stimulation, ovarian response and implantation after superovulation, gonadotropin effects after ovariectomy, and ovarian NSMF protein expression. SETTING: University research laboratory. PATIENTS: None; mice were used. INTERVENTIONS: Gonadotropin-releasing hormone stimulation, superovulation, and ovariectomy in separate experiments. MAIN OUTCOME MEASURES: Gene expression in the hypothalamus, pituitary, and ovary; ovarian response and implantation after superovulation; serum gonadotropins after GnRH stimulation and ovariectomy; Western blot to measure ovarian NSMF expression. RESULTS: We found increased hypothalamic Kiss1, Gnrh1, and Jak2 mRNA expression in female Nsmf KO vs. wild type (WT) mice. However, pituitary gonadotropin, and GnRH receptor gene expression was not affected, and serum gonadotropin levels were normal. Gonadotropins increased after ovariectomy for both groups. Baseline Kiss1, Fshr, Prkaca, Prkar1a, and Gdf9 ovarian mRNA expression was increased and Cyp19a1 expression was decreased in Nsmf KO mice, while superovulated Nsmf KO mice had reduced ovarian Kiss1r, Prkar1a, and Fshr mRNA expression, 50% less oocytes, and normal implantation. Western blot demonstrated NSMF protein expression in the ovary of WT mice. CONCLUSIONS: Altered hypothalamic and ovarian gene expression was demonstrated in female Nsmf KO mice. It is possible that increased hypothalamic Gnrh1 and Kiss1 mRNA expression could compensate for reduced NSMF enabling a normal pituitary gonadotropin response. Impaired superovulation response, altered ovarian gene expression, and decreased number of oocytes indicate ovarian dysfunction, but a uterine factor cannot be excluded. These findings provide an anatomic basis for future mechanistic studies of subfertility in female Nsmf KO mice.


Assuntos
Infertilidade , Kisspeptinas , Humanos , Feminino , Camundongos , Animais , Camundongos Knockout , Hormônio Liberador de Gonadotropina , Gonadotropinas Hipofisárias , RNA Mensageiro/metabolismo
2.
Mol Cell Endocrinol ; 534: 111334, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34062169

RESUMO

Hypogonadotropic hypogonadism, which may be normosmic (nHH) or anosmic/hyposmic, known as Kallmann syndrome (KS), is due to gonadotropin-releasing hormone deficiency, which results in absent puberty and infertility. Investigation of the genetic basis of nHH/KS over the past 35 years has yielded a substantial increase in our understanding, as variants in 44 genes in OMIM account for ~50% of cases. The first genes for KS (ANOS1) and nHH (GNRHR) were followed by the discovery that FGFR1 variants may cause either nHH or KS. Associated anomalies include midline facial defects, neurologic deficits, cardiac anomalies, and renal agenesis, among others. Mouse models for all but one gene (ANOS1) generally support findings in humans. About half of the known genes implicated in nHH/KS are inherited as autosomal dominant and half are autosomal recessive, whereas only 7% are X-linked recessive. Digenic and oligogenic inheritance has been reported in 2-20% of patients, most commonly with variants in genes that may result in either nHH or KS inherited in an autosomal dominant fashion. In vitro analyses have only been conducted for both gene variants in eight cases and for one gene variant in 20 cases. Rigorous confirmation that two gene variants in the same individual cause the nHH/KS phenotype is lacking for most. Clinical diagnosis is probably best accomplished by targeted next generation sequencing of the known candidate genes with confirmation by Sanger sequencing. Elucidation of the genetic basis of nHH/KS has resulted in an enhanced understanding of this disorder, as well as normal puberty, which makes genetic diagnosis clinically relevant.


Assuntos
Proteínas da Matriz Extracelular/genética , Síndrome de Kallmann/genética , Proteínas do Tecido Nervoso/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptores LHRH/genética , Animais , Modelos Animais de Doenças , Aconselhamento Genético , Variação Genética , Humanos , Padrões de Herança , Masculino , Camundongos
3.
J Assist Reprod Genet ; 38(7): 1745-1754, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33709343

RESUMO

By 2030, WHO estimates that 1.4 million reproductive-aged women will be diagnosed with cancer annually. Fortunately, cancer is no longer considered an incurable disease in many cases. From 2008-2014, 85% of women under the age of 45 years diagnosed with cancer survived. This increase in survival rate has shifted attention from focusing exclusively on preserving life to focusing on preserving quality of life after treatment. One aspect of this is preserving the ability to have a biological family. Oncofertility, the field that bridges oncology and reproductive endocrinology with the goal of preserving fertility, offers these patients hope. Though it is clear that ASCO and ASRM recognize the importance of fertility preservation as an aspect of comprehensive oncology care, there are not yet unified guidelines for oncologists and fertility specialists for treating oncofertility patients. First, we identify the need for reproductive counseling prior to cancer treatment, as many patients report that their fertility preservation concerns are not addressed adequately. We then delineate multi-modal fertility preservation options that are available and appropriate for different patients with corresponding outcomes using different treatments. We discuss the unique challenges and considerations, including ethical dilemmas, for delivering timely and comprehensive care specifically for oncofertility patients. Finally, we address the multidisciplinary team that includes oncologists, reproductive endocrinologists, surgeons as well as their staff, nurses, genetic counselors, mental health professionals, and more. Since oncofertility patient care requires the coordination of both physician teams, one set of unified guidelines will greatly improve quality of care.


Assuntos
Preservação da Fertilidade/métodos , Neoplasias/terapia , Indução da Ovulação/métodos , Adulto , Aconselhamento , Criopreservação , Endocrinologistas , Feminino , Preservação da Fertilidade/ética , Pessoal de Saúde , Humanos , Infertilidade/etiologia , Infertilidade/prevenção & controle , Masculino , Síndrome de Hiperestimulação Ovariana/etiologia , Guias de Prática Clínica como Assunto , Gravidez , Qualidade de Vida , Preservação do Sêmen
4.
Stem Cells Dev ; 28(2): 101-113, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30328800

RESUMO

Mouse Embryonic Stem Cells (mESCs) are unique in their self-renewal and pluripotency. Hypothetically, mESCs model gestational stress effects or stresses of in vitro fertilization/assisted reproductive technologies or drug/environmental exposures that endanger embryos. Testing mESCs stress responses should diminish and expedite in vivo embryo screening. Transgenic mESCs for green fluorescent protein (GFP) reporters of differentiation use the promoter for platelet-derived growth factor receptor (Pdgfr)a driving GFP expression to monitor hyperosmotic stress-forced mESC proliferation decrease (stunting), and differentiation increase that further stunts mESC population growth. In differentiating mESCs Pdgfra marks the first-lineage extraembryonic primitive endoderm (ExEndo). Hyperosmotic stress forces mESC differentiation gain (Pdgfra-GFP) in monolayer or three-dimensional embryoid bodies. Despite culture with potency-maintaining leukemia inhibitory factor (LIF), stress forces ExEndo as assayed using microplate readers and validated by coexpression of Pdgfra-GFP, Disabled 2 (Dab2), and laminin by immunofluorescence and GFP protein and Dab2 by immunoblot. In agreement with previous reports, Rex1 and Oct4 loss was inversely proportional to increased Pdgfra-GFP mESC after treatment with high hyperosmotic sorbitol despite LIF. The increase in subpopulations of Pdgfra-GFP+ cells>background at ∼23% was similar to the previously reported ∼25% increase in Rex1-red fluorescent protein (RFP)-negative subpopulation at matched high sorbitol doses. By microplate reader, there is a ∼7-11-fold increase in GFP at a high nonmorbid and a morbid dose despite LIF, compared with LIF alone. By flow cytometry (FACS), the subpopulation of Pdgfra-GFP+ cells>background increases ∼8-16-fold at these doses. Taken together, the microplate, FACS, immunoblot, and immunofluorescence data suggest that retinoic acid or hyperosmotic stress forces dose-dependent differentiation whether LIF is present or not and this is negatively correlated with and possibly compensates for stress-forced diminished ESC population expansion and potency loss.


Assuntos
Diferenciação Celular , Linhagem da Célula , Ensaios de Triagem em Larga Escala/métodos , Células-Tronco Embrionárias Murinas/citologia , Pressão Osmótica , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Células Cultivadas , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Laminina/genética , Laminina/metabolismo , Camundongos , Células-Tronco Embrionárias Murinas/metabolismo , Regiões Promotoras Genéticas , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo
5.
J Assist Reprod Genet ; 35(8): 1359-1366, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29882092

RESUMO

Here we examine recent evidence suggesting that many drugs and diet supplements (DS), experimental AMP-activated protein kinase (AMPK) agonists as well as energy-depleting stress, lead to decreases in anabolism, growth or proliferation, and potency of cultured oocytes, embryos, and stem cells in an AMPK-dependent manner. Surprising data for DS and drugs that have some activity as AMPK agonists in in vitro experiments show possible toxicity. This needs to be balanced against a preponderance of evidence in vivo that these drugs and DS are beneficial for reproduction. We here discuss and analyze data that leads to two possible conclusions: First, although DS and drugs that have some of their therapeutic mechanisms mediated by AMPK activity associated with low ATP levels, some of the associated health problems in vivo and in vitro fertilization/assisted reproductive technologies (IVF/ART) may be better-treated by increasing ATP production using CoQ10 (Ben-Meir et al., Aging Cell 14:887-895, 2015). This enables high developmental trajectories simultaneous with solving stress by energy-requiring responses. In IVF/ART, it is ultimately best to maintain handling and culture of gametes and embryos in the quietest state with low metabolic activity (Leese et al., Mol Hum Reprod 14:667-672, 2008; Leese, Bioessays 24 (9):845-849, 2002) using back-to-nature or simplex algorithms to identify optima (Biggers, Reprod Biomed Online 4 Suppl 1:30-38, 2002). Stress markers, such as checkpoint proteins like TRP53 (aka p53) (Ganeshan et al., Exp Cell Res 358:227-233, 2017); Ganeshan et al., Biol Reprod 83:958-964, 2010) and a small set of kinases from the protein kinome that mediate enzymatic stress responses, can also be used to define optima. But, some gametes or embryos may have been stressed in vivo prior to IVF/ART or IVF/ART optimized for one outcome may be suboptimal for another. Increasing nutrition or adding CoQ10 to increase ATP production (Yang et al., Stem Cell Rev 13:454-464, 2017), managing stress enzyme levels with inhibitors (Xie et al., Mol Hum Reprod 12:217-224, 2006), or adding growth factors such as GM-CSF (Robertson et al., J Reprod Immunol 125:80-88, 2018); Chin et al., Hum Reprod 24:2997-3009, 2009) may increase survival and health of cultured embryos during different stress exposure contexts (Puscheck et al., Adv Exp Med Biol 843:77-128, 2015). We define "stress" as negative stimuli which decrease normal magnitude and speed of development, and these can be stress hormones, reactive oxygen species, inflammatory cytokines, or physical stimuli such as hypoxia. AMPK is normally activated by high AMP, commensurate with low ATP, but it was recently shown that if glucose is present inside the cell, AMPK activation by low ATP/high AMP is suppressed (Zhang et al., Nature 548:112-116, 2017). As we discuss in more detail below, this may also lead to greater AMPK agonist toxicity observed in two-cell embryos that do not import glucose. Stress in embryos and stem cells increases AMPK in large stimulation indexes but also direness indexes; the fastest AMPK activation occurs when stem cells are shifted from optimal oxygen to lower or high levels (Yang et al., J Reprod Dev 63:87-94, 2017). CoQ10 use may be better than risking AMPK-dependent metabolic and developmental toxicity when ATP is depleted and AMPK activated. Second, the use of AMPK agonists, DS, and drugs may best be rationalized when insulin resistance or obesity leads to aberrant hyperglycemia and hypertriglyceridemia, and obesity that negatively affect fertility. Under these conditions, beneficial effects of AMPK on increasing triglyceride and fatty acid and glucose uptake are important, as long as AMPK agonist exposures are not too high or do not occur during developmental windows of sensitivity. During these windows of sensitivity suppression of anabolism, proliferation, and stemness/potency due to AMPK activity, or overexposure may stunt or kill embryos or cause deleterious epigenetic changes.


Assuntos
Aborto Espontâneo/patologia , Suplementos Nutricionais/efeitos adversos , Obesidade/tratamento farmacológico , Proteínas Quinases/efeitos dos fármacos , Quinases Proteína-Quinases Ativadas por AMP , Aborto Espontâneo/induzido quimicamente , Aborto Espontâneo/enzimologia , Trifosfato de Adenosina/metabolismo , Blastocisto/efeitos dos fármacos , Feminino , Humanos , Resistência à Insulina/genética , Metformina/uso terapêutico , Oócitos/efeitos dos fármacos , Gravidez , Técnicas de Reprodução Assistida/tendências , Células-Tronco/efeitos dos fármacos
6.
J Pediatr Adolesc Gynecol ; 28(6): e189-91, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26376072

RESUMO

BACKGROUND: We present a patient with primary amenorrhea and a rare combination of anomalies. She was found to have a septate uterus, double cervix, and a longitudinal and a low transverse vaginal septum. CASE: An 18-year-old girl with primary amenorrhea presented with severe monthly pelvic pain. Examination and imaging revealed a thin transverse vaginal septum, complete septate uterus, double cervix, and a longitudinal vaginal septum. The transverse and longitudinal vaginal septa were excised and repaired. SUMMARY AND CONCLUSION: Although repetitive pregnancy loss and preterm birth are associated with various Müllerian duct anomalies, clinicians should also be suspicious of the presented anomaly in cases of primary amenorrhea and cyclic pelvic pain. To our knowledge, this is the only case of simultaneous septate uterus with longitudinal and transverse vaginal septum and the second case of combined longitudinal and transverse septum, which caused primary amenorrhea. This rare anomaly further supports the bidirectional regression theory of Müllerian development.


Assuntos
Ductos Paramesonéfricos/anormalidades , Anormalidades Urogenitais/diagnóstico , Útero/anormalidades , Vagina/anormalidades , Adolescente , Amenorreia/etiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Ductos Paramesonéfricos/cirurgia , Dor Pélvica/etiologia , Gravidez , Anormalidades Urogenitais/cirurgia , Útero/cirurgia , Vagina/cirurgia
7.
Reprod Fertil Dev ; 27(1): 31-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25472042

RESUMO

Obese women experience worse reproductive outcomes than normal weight women, specifically infertility, pregnancy loss, fetal malformations and developmental delay of offspring. The aim of the present study was to use a genetic mouse model of obesity to recapitulate the human reproductive phenotype and further examine potential mechanisms and therapies. New inbred, polygenic Type 2 diabetic TallyHO mice and age-matched control C57BL/6 mice were superovulated to obtain morula or blastocyst stage embryos that were cultured in human tubal fluid (HTF) medium. Deoxyglucose uptake was determined for individual insulin-stimulated blastocysts. Apoptosis was detected by confocal microscopy using the terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL) assay and Topro-3 nuclear dye. Embryos were scored for TUNEL-positive as a percentage of total nuclei. AMP-activated protein kinase (AMPK) activation, tumour necrosis factor (TNF)-α expression and adiponectin expression were analysed by western immunoblot and confocal immunofluorescent microscopy. Lipid accumulation was assayed by BODIPY. Comparisons were made between TallyHO morulae cultured to blastocyst embryos in either HTF medium or HTF medium with 25 µg mL(-1) metformin. TallyHO mice developed whole body abnormal insulin tolerance, had decreased litter sizes and increased non-esterified fatty acid levels. Blastocysts from TallyHO mice exhibited increased apoptosis, decreased insulin sensitivity and decreased AMPK. A possible cause for the insulin resistance and abnormal AMPK phosphorylation was the increased TNF-α expression and lipid accumulation, as detected by BODIPY, in TallyHO blastocysts and decreased adiponectin. Culturing TallyHO morulae with the AMPK activator metformin led to a reversal of all the abnormal findings, including increased AMPK phosphorylation, improved insulin-stimulated glucose uptake and normalisation of lipid accumulation. Women with obesity and insulin resistance experience poor pregnancy outcomes. Previously we have shown in mouse models of insulin resistance that AMPK activity is decreased and that activators of AMPK reverse poor embryo outcomes. Here, we show for the first time using a genetically altered obese model, not a diet-induced model, that metformin reverses many of the adverse effects of obesity at the level of the blastocyst. Expanding on this we determine that activation of AMPK via metformin reduces lipid droplet accumulation, presumably by eliminating the inhibitory effects of TNF-α, resulting in normalisation of fatty acid oxidation and HADH2 (hydroxyacyl-CoA dehydrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase (trifunctional protein), alpha subunit) activity. Metformin exposure in vitro was able to partially reverse these effects, at the level of the blastocyst, and may thus be effective in preventing the adverse effects of obesity on pregnancy and reproductive outcomes.


Assuntos
Blastocisto/metabolismo , Diabetes Mellitus Tipo 2/complicações , Metformina/farmacologia , Obesidade/etiologia , Reprodução/efeitos dos fármacos , 3-Hidroxiacil-CoA Desidrogenases/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Ácidos Graxos/metabolismo , Feminino , Humanos , Marcação In Situ das Extremidades Cortadas , Resistência à Insulina/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Microscopia Confocal , Gravidez
8.
Biol Reprod ; 85(4): 678-83, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21653893

RESUMO

Free fatty acids (FFAs) are energy substrates for many cell types, but in excess, some FFAs can accumulate in nonadipose cells, inducing apoptosis. Also known as lipotoxicity, this phenomenon may play a role in the development of obesity-related disease. Obesity is common among reproductive age women and is associated with adverse pregnancy and fetal outcomes; however, little is known about the effects of excess FFAs on embryos and subsequent fetal development. To address this knowledge gap, murine blastocysts were cultured in excess palmitic acid (PA), the most abundant saturated FFA in human serum, and ovarian follicular fluid. Targets susceptible to aberrations in maternal physiology, including embryonic IGF1 receptor (IGF1R) expression, glutamic pyruvate transaminase (GPT2) activity, and nuclei count, were measured. PA-exposed blastocysts demonstrated altered IGF1R expression, increased GPT2 activity, and decreased nuclei count. Trophoblast stem cells derived from preimplantation embryos were also cultured in PA. Cells exposed to increasing doses of PA demonstrated increased apoptosis and decreased proliferation. To demonstrate long-term effects of brief PA exposure, blastocysts cultured for 30 h in PA were transferred into foster mice, and pregnancies followed through Embryonic Day (ED)14.5 or delivery. Fetuses resulting from PA-exposed blastocysts were smaller than controls at ED14.5. Delivered pups were also smaller but demonstrated catch-up growth and ultimately surpassed control pups in weight. Altogether, our data suggest brief PA exposure results in altered embryonic metabolism and growth, with lasting adverse effects on offspring, providing further insight into the pathophysiology of maternal obesity.


Assuntos
Blastocisto/metabolismo , Desenvolvimento Fetal , Retardo do Crescimento Fetal/etiologia , Obesidade/etiologia , Ácido Palmítico/efeitos adversos , Animais , Apoptose , Blastocisto/citologia , Peso Corporal , Contagem de Células , Proliferação de Células , Células Cultivadas , Cruzamentos Genéticos , Ectogênese , Transferência Embrionária , Feminino , Feto/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Camundongos , Gravidez , Transaminases/metabolismo , Trofoblastos/citologia , Trofoblastos/metabolismo
9.
Endocrinology ; 151(8): 4039-46, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20573727

RESUMO

Associations between maternal obesity and adverse fetal outcomes are well documented, but the mechanisms involved are largely unknown. Most previous work has focused on postconceptional events, however, our laboratory has shown pre- and periconceptional aberrations in maternal glucose metabolism have adverse effects on oocytes and embryos that carry on to the fetus. To demonstrate effects of maternal obesity in the pre- and periconceptional periods, we compared reproductive tissues from diet-induced obese female mice to those of control mice. Ovaries were either stained for follicular apoptosis or dissected and evaluated for oocyte size and meiotic maturation. Mice were also mated and followed for reproductive outcomes including preimplantation embryonic IGF-I receptor (IGF-IR) immunostaining, midgestation fetal growth, and midgestational placental IGF receptor 2 (Igf2r) mRNA. Delivered pups were followed for growth and development of markers of metabolic syndrome. Compared with controls, obese mice had significantly more apoptotic ovarian follicles, smaller and fewer mature oocytes, decreased embryonic IGF-IR staining, smaller fetuses, increased placental Igf2r mRNA, and smaller pups. All weaned pups were fed a regular diet. At 13 wk pups delivered from obese mice were significantly larger, and these pups demonstrated glucose intolerance and increased cholesterol and body fat suggesting early development of a metabolic-type syndrome. Together, our findings suggest maternal obesity has adverse effects as early as the oocyte and preimplantation embryo stage and that these effects may contribute to lasting morbidity in offspring, underscoring the importance of optimal maternal weight and nutrition before conception.


Assuntos
Dieta/efeitos adversos , Transtornos do Crescimento/etiologia , Obesidade/etiologia , Oócitos/patologia , Ovário/anormalidades , Efeitos Tardios da Exposição Pré-Natal/patologia , Animais , Animais Recém-Nascidos , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/farmacologia , Modelos Animais de Doenças , Embrião de Mamíferos , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Transtornos do Crescimento/patologia , Fenômenos Fisiológicos da Nutrição Materna/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/patologia , Ovário/patologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/etiologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia
10.
Reproduction ; 136(3): 335-44, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18577554

RESUMO

Maternal insulin resistance results in poor pregnancy outcomes. In vivo and in vitro exposure of the murine blastocyst to high insulin or IGF1 results in the down-regulation of the IGF1 receptor (IGF1R). This in turn leads to decreased glucose uptake, increased apoptosis, as well as pregnancy resorption and growth restriction. Recent studies have shown that blastocyst activation of AMP-activated protein kinase (AMPK) reverses these detrimental effects; however, the mechanism was not clear. The objective of this study was to determine how AMPK activation rescues the insulin-resistant blastocyst. Using trophoblast stem (TS) cells derived from the blastocyst, insulin resistance was recreated by transfecting with siRNA to Igf1r and down-regulating expression of the protein. These cells were then exposed to AMPK activators 5-aminoimidazole-4-carboxamide riboside and phenformin, and evaluated for apoptosis, insulin-stimulated 2-deoxyglucose uptake, PI3-kinase activity, and levels of phospho-AKT, phospho-mTor, and phospho-70S6K. Surprisingly, disrupted insulin signaling led to decreased AMPK activity in TS cells. Activators reversed these effects by increasing the AMP/ATP ratio. Moreover, this treatment increased insulin-stimulated 2-deoxyglucose transport and cell survival, and led to an increase in PI3-kinase activity, as well as increased P-mTOR and p70S6K levels. This study is the first to demonstrate significant crosstalk between the AMPK and insulin signaling pathways in embryonic cells, specifically the enhanced response of PI3K/AKT/mTOR to AMPK activation. Decreased insulin signaling also resulted in decreased AMPK activation. These findings provide mechanistic targets in the AMPK signaling pathway that may be essential for improved pregnancy success in insulin-resistant states.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Blastocisto/metabolismo , Resistência à Insulina , Insulina/metabolismo , Transdução de Sinais/fisiologia , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Animais , Apoptose/efeitos dos fármacos , Western Blotting/métodos , Linhagem Celular , Desoxiglucose/metabolismo , Ativação Enzimática , Feminino , Hipoglicemiantes/farmacologia , Camundongos , Fenformin/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Receptor IGF Tipo 1/genética , Ribonucleosídeos/farmacologia , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo
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