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1.
Am J Physiol Endocrinol Metab ; 310(3): E238-47, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26646100

RESUMO

Among potential contributors for the increased incidence of metabolic diseases is the developmental exposure to endocrine-disrupting chemicals such as bisphenol A (BPA). BPA is an estrogenic chemical used in a variety of consumer products. Evidence points to interactions of BPA with the prevailing environment. The aim of this study was to assess the effects of prenatal exposure to BPA on postnatal metabolic outcomes, including insulin resistance, adipose tissue distribution, adipocyte morphometry, and expression of inflammatory markers in adipose tissue as well as to assess whether postnatal overfeeding would exacerbate these effects. Findings indicate that prenatal BPA exposure leads to insulin resistance in adulthood in the first breeder cohort (study 1), but not in the second cohort (study 2), which is suggestive of potential differences in genetic susceptibility. BPA exposure induced adipocyte hypertrophy in the visceral fat depot without an accompanying increase in visceral fat mass or increased CD68, a marker of macrophage infiltration, in the subcutaneous fat depot. Cohens effect size analysis found the ratio of visceral to subcutaneous fat depot in the prenatal BPA-treated overfed group to be higher compared with the control-overfed group. Altogether, these results suggest that exposure to BPA during fetal life at levels found in humans can program metabolic outcomes that lead to insulin resistance, a forerunner of type 2 diabetes, with postnatal obesity failing to manifest any interaction with prenatal BPA relative to insulin resistance and adipocyte hypertrophy.


Assuntos
Adipócitos Brancos/efeitos dos fármacos , Adiposidade/efeitos dos fármacos , Compostos Benzidrílicos/farmacologia , Estrogênios não Esteroides/farmacologia , Resistência à Insulina , Macrófagos/efeitos dos fármacos , Obesidade , Fenóis/farmacologia , Efeitos Tardios da Exposição Pré-Natal , Adipócitos Brancos/patologia , Animais , Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Feminino , Predisposição Genética para Doença , Hipertrofia , Gordura Intra-Abdominal/efeitos dos fármacos , Gordura Intra-Abdominal/imunologia , Gordura Intra-Abdominal/patologia , Macrófagos/imunologia , Hipernutrição , Gravidez , Ovinos , Gordura Subcutânea/efeitos dos fármacos
2.
Eur Heart J Case Rep ; 8(7): ytae343, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39071535

RESUMO

Background: Cardiac tamponade due to perforation of a cardiac chamber is a rare complication occurring in only 0.3% of patients undergoing permanent pacemaker (PM) implantation. Notably, perforation of the right coronary artery (RCA) following permanent PM implantation has only been reported twice in the literature. We report a rare case of RCA perforation leading to life-threatening cardiac tamponade with symptom onset 4 days after PM implantation. Case summary: A 75-year-old woman underwent permanent PM implantation without any difficulties in placing pacemaker leads and with good thresholds. Four days later, the patient was readmitted in a state of shock due to cardiac tamponade. A blood gas analysis on the bloody pericardial effusion raised suspicion of ongoing arterial bleeding. A CT scan ruled out aortic dissection; instead, the source of bleeding was identified as a perforation in the RCA, which was managed surgically. Discussion: This case highlights the necessity of coronary artery perforation being among the differential diagnoses of cardiac tamponade after PM implantation, and it stresses the usefulness of performing a blood gas analysis on the bloody pericardial effusion.

3.
Eur Heart J Acute Cardiovasc Care ; 13(9): 658-661, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39217624

RESUMO

AIMS: In a recent meta-analysis of randomized controlled trials, routine use of veno-arterial ECMO (VA-ECMO) did not improve outcomes in patients with acute myocardial infarction-related cardiogenic shock (AMI-CS), while a microaxial flow pump reduced mortality in a selected group of patients with AMI-CS in the DanGer-Shock trial. METHODS AND RESULTS: Individual patient data of patients included in four randomized clinical trials investigating the routine use of VA-ECMO in AMI-CS were centrally analysed. For the purpose of this sub-analysis, DanGer-Shock-like patients were analysed (STEMI only, presumed low likelihood of brain injury). The primary endpoint was 180-day all-cause mortality. A total of 202 patients (106 randomized to VA-ECMO and 96 to control) were included. There were no differences in baseline characteristics, angiographic and interventional features between the two groups. Mortality after 6 months was numerically lower with VA-ECMO between the groups [45% in VA-ECMO group vs. 51% in control group; hazard ratio, 0.84; 95% confidence interval (CI), 0.56-1.26], while major bleeding (OR, 2.24; 95% CI, 1.08-4.64) and peripheral vascular complications (OR, 3.65; 95% CI, 1.15-11.56) were increased with the use of VA-ECMO. CONCLUSION: In this exploratory subgroup analysis in patients with CS, STEMI, and a low likelihood of brain injury, there was no mortality benefit with the routine use of VA-ECMO. However, as indicated by the large confidence intervals, the statistical power was limited to draw definite conclusions.


Assuntos
Oxigenação por Membrana Extracorpórea , Infarto do Miocárdio , Choque Cardiogênico , Humanos , Oxigenação por Membrana Extracorpórea/métodos , Infarto do Miocárdio/complicações , Infarto do Miocárdio/terapia , Infarto do Miocárdio/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Choque Cardiogênico/terapia , Choque Cardiogênico/mortalidade , Choque Cardiogênico/etiologia , Resultado do Tratamento
4.
J Clin Med ; 12(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37297879

RESUMO

Neutrophil gelatinase-associated lipocalin (NGAL) is an inflammatory biomarker related to acute kidney injury (AKI). Including 1892 consecutive patients with ST-elevation myocardial infarction (STEMI), in which NGAL was measured in 1624 (86%) on admission and in a consecutive subgroup at 6-12 h (n = 163) and 12-24 h (n = 222) after admission, this study aimed to evaluate the prognostic value of NGAL in predicting AKI and mortality. Patients were stratified based on whether their admission NGAL plasma concentration was greater than or equal to/less than the median. The primary endpoint was a composite of the first occurrence of AKI or all-cause death within 30 days. AKI was classified by the maximal plasma creatinine increase from baseline during index admission as KDIGO1 (<200% increase) or KDIGO23 (≥200% increase) according to the Kidney Disease Improving Global Outcomes (KDIGO) system. Admission NGAL > the median was independently associated with a higher risk of severe AKI (KDIGO2-3) and 30-day all-cause mortality when adjusted for age, admission systolic blood pressure and high-sensitivity C-reactive protein, left-ventricular ejection fraction, known kidney dysfunction, and cardiogenic shock with an odds ratio (95% confidence interval) of 2.26 (1.18-4.51), p = 0.014. Finally, we observed increasing predictive values in a subgroup during the first day of hospitalization suggesting that assessment of NGAL should be delayed for optimal prognostic purposes.

5.
Compr Physiol ; 12(4): 4185-4214, 2022 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-36073751

RESUMO

Circadian rhythms are endogenously generated, daily patterns of behavior and physiology that are essential for optimal health and disease prevention. Disruptions to circadian timing are associated with a host of maladies, including metabolic disease and obesity, diabetes, heart disease, cancer, and mental health disturbances. The circadian timing system is hierarchically organized, with a master circadian clock located in the suprachiasmatic nucleus (SCN) of the anterior hypothalamus and subordinate clocks throughout the CNS and periphery. The SCN receives light information via a direct retinal pathway, synchronizing the master clock to environmental time. At the cellular level, circadian rhythms are ubiquitous, with rhythms generated by interlocking, autoregulatory transcription-translation feedback loops. At the level of the SCN, tight cellular coupling maintains rhythms even in the absence of environmental input. The SCN, in turn, communicates timing information via the autonomic nervous system and hormonal signaling. This signaling couples individual cellular oscillators at the tissue level in extra-SCN brain loci and the periphery and synchronizes subordinate clocks to external time. In the modern world, circadian disruption is widespread due to limited exposure to sunlight during the day, exposure to artificial light at night, and widespread use of light-emitting electronic devices, likely contributing to an increase in the prevalence, and the progression, of a host of disease states. The present overview focuses on the circadian control of endocrine secretions, the significance of rhythms within key endocrine axes for typical, homeostatic functioning, and implications for health and disease when dysregulated. © 2022 American Physiological Society. Compr Physiol 12: 1-30, 2022.


Assuntos
Transtornos Cronobiológicos , Relógios Circadianos , Doenças Metabólicas , Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Humanos , Núcleo Supraquiasmático/fisiologia
6.
Trials ; 23(1): 952, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36414975

RESUMO

BACKGROUND: Patients resuscitated from out-of-hospital cardiac arrest (OHCA) have a high morbidity and mortality risk and often develop post-cardiac arrest syndrome (PCAS) involving systemic inflammation. The severity of the inflammatory response is associated with adverse outcome, with anoxic irreversible brain injury as the leading cause of death following resuscitated OHCA. The study aimed to investigate the anti-inflammatory and neuroprotective effect of pre-hospital administration of a high-dose glucocorticoid following OHCA. METHODS: The study is an investigator-initiated, randomized, multicenter, single-blinded, placebo-controlled, clinical trial. Inclusion will continue until one hundred twenty unconscious OHCA patients surviving a minimum of 72 h are randomized. Intervention is a 1:1 randomization to an infusion of methylprednisolone 250 mg following a minimum of 5 min of sustained return of spontaneous circulation in the pre-hospital setting. Methylprednisolone will be given as a bolus infusion of 1 × 250 mg (1 × 4 mL) over a period of 5 min. Patients allocated to placebo will receive 4 mL of isotonic saline (NaCl 0.9%). Main eligibility criteria are OHCA of presumed cardiac cause, age ≥ 18 years, Glasgow Coma Scale ≤ 8, and sustained ROSC for at least 5 min. Co-primary endpoint: Reduction of interleukin-6 and neuron-specific-enolase. Secondary endpoints: Markers of inflammation, brain, cardiac, kidney and liver damage, hemodynamic and hemostatic function, safety, neurological function at follow-up, and mortality. A research biobank is set up with blood samples taken daily during the first 72 h from hospitalization to evaluate primary and secondary endpoints. DISCUSSION: We hypothesize that early anti-inflammatory steroid treatment in the pre-hospital setting can mitigate the progression of PCAS following resuscitated OHCA. Primary endpoints will be assessed through analyses of biomarkers for inflammation and neurological damage taken during the first 72 h of admission. TRIAL REGISTRATION: EudraCT number: 2020-000855-11 ; submitted March 30, 2020 ClinicalTrials.gov Identifier: NCT04624776; submitted October 12, 2020, first posted November 10, 2020.


Assuntos
Fármacos Neuroprotetores , Parada Cardíaca Extra-Hospitalar , Humanos , Adolescente , Parada Cardíaca Extra-Hospitalar/diagnóstico , Parada Cardíaca Extra-Hospitalar/tratamento farmacológico , Fármacos Neuroprotetores/efeitos adversos , Resultado do Tratamento , Anti-Inflamatórios/efeitos adversos , Inflamação , Metilprednisolona/efeitos adversos , Esteroides/uso terapêutico
7.
Adv Pharmacol ; 92: 279-346, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34452689

RESUMO

With the advent of industrialization, humans are exposed to a wide range of environmental chemicals, many with endocrine disrupting potential. As successful maintenance of pregnancy and fetal development are under tight hormonal control, the gestational exposure to environmental endocrine disrupting chemicals (EDC) have the potential to adversely affect the maternal milieu and support to the fetus, fetal developmental trajectory and birth outcomes. This chapter summarizes the impact of exposure to EDCs both individually and as mixtures during pregnancy, the immediate and long-term consequences of such exposures on the mother and fetus, the direct and indirect mechanisms through which they elicit their effects, factors that modify their action, and the research directions to focus future investigations.


Assuntos
Disruptores Endócrinos , Disruptores Endócrinos/toxicidade , Feminino , Humanos , Exposição Materna/efeitos adversos , Gravidez
8.
Front Cell Dev Biol ; 8: 426, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32695775

RESUMO

A growing number of studies point to reduced fertility upon chronic exposure to endocrine-disrupting chemicals (EDCs) such as phthalates and plasticizers. These toxins are ubiquitous and are often found in food and beverage containers, medical devices, as well as in common household and personal care items. Animal studies with EDCs, such as phthalates and bisphenol A have shown a dose-dependent decrease in fertility and embryo toxicity upon chronic exposure. However, limited research has been conducted on the acute effects of these EDCs on male fertility. Here we used a murine model to test the acute effects of four ubiquitous environmental toxins: bisphenol A (BPA), di-2-ethylhexyl phthalate (DEHP), diethyl phthalate (DEP), and dimethyl phthalate (DMP) on sperm fertilizing ability and pre-implantation embryo development. The most potent of these toxins, di-2-ethylhexyl phthalate (DEHP), was further evaluated for its effect on sperm ion channel activity, capacitation status, acrosome reaction and generation of reactive oxygen species (ROS). DEHP demonstrated a profound hazardous effect on sperm fertility by producing an altered capacitation profile, impairing the acrosome reaction, and, interestingly, also increasing ROS production. These results indicate that in addition to its known chronic impact on reproductive potential, DEHP also imposes acute and profound damage to spermatozoa, and thus, represents a significant risk to male fertility.

9.
Shock ; 53(3): 299-306, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31058719

RESUMO

BACKGROUND: Thirty-day mortality in ST-elevation myocardial infarction (STEMI) patients is primarily driven by cardiogenic shock (CS). High neutrophil counts and high neutrophil/lymphocyte ratios (NLR) have previously been associated with mortality in STEMI patients; however, there is only sparse knowledge regarding their association with CS. PURPOSE: We sought to assess the associations between neutrophil count and NLR with the development of CS as well as 30-day mortality in STEMI patients. METHODS: Patients admitted with STEMI at two tertiary Heart Centres throughout 1 year were included in the study and stratified into quartiles according to the level of leukocyte count upon admission. The primary endpoint was development of CS both before (early CS) and after leaving the catheterization laboratory (late CS). The secondary endpoint was all-cause 30-day mortality. RESULTS: A total of 1,892 STEMI patients were included, whereof 194 (10%) developed CS while 122 (6.4%) died within 30 days. Patients in the highest quartile of neutrophils (OR: 2.54; 95% CI: 1.40-4.60; P = 0.002) and NLR (OR: 3.64; 95% CI: 2.02-6.54; P<0.0001) were at increased risk of developing late CS compared with patients in the lower quartiles, whereas there was no risk difference across quartiles regarding development of early CS. Both biomarkers correlated strongly to an increased 30-day mortality (plogrank<0.0001) and, moreover, a high level of neutrophils was independently associated with 30-day mortality (HR: 1.95; 95% CI: 1.25-3.03; P = 0.003). CONCLUSION: High levels of neutrophils and a high NLR upon admission for STEMI were independently associated with an increased risk of developing late CS and, additionally, both biomarkers showed association to 30-day mortality.


Assuntos
Contagem de Leucócitos , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Choque Cardiogênico/sangue , Choque Cardiogênico/etiologia , Idoso , Biomarcadores/sangue , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Valor Preditivo dos Testes , Taxa de Sobrevida
10.
J Neuroendocrinol ; 31(11): e12798, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31550401

RESUMO

In spontaneously ovulating rodent species, the timing of the luteinising hormone (LH) surge is controlled by the master circadian pacemaker in the suprachiasmatic nucleus (SCN). The SCN initiates the LH surge via the coordinated control of two opposing neuropeptidergic systems that lie upstream of the gonadotrophin-releasing hormone (GnRH) neuronal system: the stimulatory peptide, kisspeptin, and the inhibitory peptide, RFamide-related peptide-3 (RFRP-3; the mammalian orthologue of avian gonadotrophin-inhibitory hormone [GnIH]). We have previously shown that the GnRH system exhibits time-dependent sensitivity to kisspeptin stimulation, further contributing to the precise timing of the LH surge. To examine whether this time-dependent sensitivity of the GnRH system is unique to kisspeptin or a more common mechanism of regulatory control, we explored daily changes in the response of the GnRH system to RFRP-3 inhibition. Female Syrian hamsters were ovariectomised to eliminate oestradiol (E2 )-negative-feedback and RFRP-3 or saline was centrally administered in the morning or late afternoon. LH concentrations and Lhß mRNA expression did not differ between morning RFRP-3-and saline-treated groups, although they were markedly suppressed by RFRP-3 administration in the afternoon. However, RFRP-3 inhibition of circulating LH at the time of the surge does not appear to act via the GnRH system because no differences in medial preoptic area Gnrh or RFRP-3 receptor Gpr147 mRNA expression were observed. Rather, RFRP-3 suppressed arcuate nucleus Kiss1 mRNA expression and potentially impacted pituitary gonadotrophs directly. Taken together, these findings reveal time-dependent responsiveness of the reproductive axis to RFRP-3 inhibition, possibly via variation in the sensitivity of arcuate nucleus kisspeptin neurones to this neuropeptide.


Assuntos
Ritmo Circadiano/fisiologia , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Neuropeptídeos/farmacologia , Reprodução/efeitos dos fármacos , Animais , Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Núcleo Arqueado do Hipotálamo/metabolismo , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/genética , Cricetinae , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/metabolismo , Gonadotropinas/metabolismo , Kisspeptinas/genética , Kisspeptinas/metabolismo , Hormônio Luteinizante/genética , Hormônio Luteinizante/metabolismo , Mesocricetus , Reprodução/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Tempo
11.
Front Cardiovasc Med ; 6: 65, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31157242

RESUMO

MicroRNA-1 (miRNA-1) has been long viewed as a muscle-specific miRNA and plays a critical role in myocardium and cardiomyocytes by controlling myocyte growth and rhythm. We identified that miRNA-1 is expressed in cardiac fibroblasts, which are one of the major non-muscle cell types in myocardium and are responsible for cardiac fibrosis in pathological conditions. In this study, we aimed to investigate the effect and mechanism of action of miRNA-1 on cardiac fibroblast proliferation. Subcutaneous angiotensin II (Ang II) infusion via osmotic minipumps for 4 weeks was used to induce myocardial interstitial fibrosis in male Sprague-Dawley rats. MiRNA-1 expression was significantly down-regulated by 68% in freshly isolated ventricular fibroblasts from Ang II-infused rats than that from control rats. Similar results were obtained in adult rat ventricular fibroblasts that were stimulated in culture by Ang II or TGFß for 48 h. Functionally, overexpression of miRNA-1 inhibited fibroblast proliferation, whereas knockdown of endogenous miRNA-1 increased fibroblast proliferation. We then identified and validated cyclin D2 and cyclin-dependent kinase 6 (CDK6) as direct targets of miRNA-1 in cardiac fibroblasts using biochemical assays. Moreover, we showed that the inhibitory effects of miRNA-1 on cardiac fibroblast proliferation can be blunted by overexpression of its target, cyclin D2. In conclusion, our findings demonstrate miRNA-1 expression and regulation in adult ventricular fibroblasts, where it acts as a novel negative regulator of adult cardiac fibroblast proliferation that is at least partially mediated by direct targeting of two cell cycle regulators. Our results expand the understanding of the regulatory roles of miRNA-1 in cardiac cells (i.e., from myocytes to a major non-muscle cells in the heart).

12.
Curr Opin Physiol ; 5: 133-140, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30957055

RESUMO

The circadian timing system orchestrates daily rhythms in physiology and behavior via the suprachiasmatic nucleus (SCN), the master brain clock. Because endocrine secretions have far-reaching influence on the brain and periphery, circadian regulation of hormones is essential for normal functioning and disruptions to circadian timing (e.g., irregular sleep patterns, limited exposure to sunlight, jet lag, nighttime light exposure) have detrimental health consequences. Herein, we provide an overview of circadian timing in three major endocrine axes, the hypothalamo-pituitary-gonadal (HPG), hypothalamo-pituitary-adrenal (HPA) and hypothalamo-pituitary-thyroid (HPT) axes, and then consider the negative health consequences of circadian disruptions in each of these systems. For example, disruptions to HPG axis circadian timing lead to a host of negative reproductive outcomes such as irregular menstrual cycles, low sperm density and increased rates of miscarriages and infertility. Dysregulation of HPA axis timing is associated with obesity and metabolic disease, whereas disruptions to the HPT axis are associated with dysregulated metabolic gene rhythms in the heart. Together, this overview underscores the significance of circadian endocrine rhythms in normal health and disease prevention.

13.
Endocrinology ; 157(12): 4641-4653, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27792406

RESUMO

Prenatal testosterone (T) treatment recapitulates the reproductive and metabolic phenotypes of polycystic ovary syndrome in female sheep. At the neuroendocrine level, prenatal T treatment results in disrupted steroid feedback on gonadotropin release, increased pituitary sensitivity to GnRH, and subsequent LH hypersecretion. Because prenatal T-treated sheep manifest functional hyperandrogenism and hyperinsulinemia, gonadal steroids and/or insulin may play a role in programming and/or maintaining these neuroendocrine defects. Here, we investigated the effects of prenatal and postnatal treatments with an androgen antagonist (flutamide [F]) or an insulin sensitizer (rosiglitazone [R]) on GnRH-stimulated LH secretion in prenatal T-treated sheep. As expected, prenatal T treatment increased the pituitary responsiveness to GnRH leading to LH hypersecretion. Neither prenatal interventions nor postnatal F treatment normalized the GnRH-stimulated LH secretion. Conversely, postnatal R treatment completely normalized the GnRH-stimulated LH secretion. At the tissue level, gestational T increased pituitary LHß, androgen receptor, and insulin receptor-ß, whereas it reduced estrogen receptor (ER)α protein levels. Although postnatal F normalized pituitary androgen receptor and insulin receptor-ß, it failed to prevent an increase in LHß expression. Contrarily, postnatal R treatment restored ERα and partially normalized LHß pituitary levels. Immunohistochemical findings confirmed changes in pituitary ERα expression to be specific to gonadotropes. In conclusion, these findings indicate that increased pituitary responsiveness to GnRH in prenatal T-treated sheep is likely a function of reduced peripheral insulin sensitivity. Moreover, results suggest that restoration of ERα levels in the pituitary may be one mechanism by which R prevents GnRH-stimulated LH hypersecretion in this sheep model of polycystic ovary syndrome-like phenotype.


Assuntos
Antagonistas de Androgênios/farmacologia , Androgênios/farmacologia , Flutamida/farmacologia , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Luteinizante/metabolismo , Síndrome do Ovário Policístico/metabolismo , Testosterona/farmacologia , Tiazolidinedionas/farmacologia , Animais , Modelos Animais de Doenças , Receptor alfa de Estrogênio/metabolismo , Feminino , Hormônio Luteinizante Subunidade beta/metabolismo , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Receptor de Insulina/metabolismo , Receptores Androgênicos/metabolismo , Rosiglitazona , Ovinos
14.
Endocrinology ; 157(2): 522-35, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26650569

RESUMO

Prenatally testosterone (T)-treated sheep present metabolic disruptions similar to those seen in women with polycystic ovary syndrome. These females exhibit an increased ratio of small to large adipocytes, which may be the earliest event in the development of adult insulin resistance. Additionally, our longitudinal studies suggest the existence of a period of compensatory adaptation during development. This study tested whether 1) in utero cotreatment of prenatally T-treated sheep with androgen antagonist (flutamide) or insulin sensitizer (rosiglitazone) prevents juvenile insulin resistance and adult changes in adipocyte size; and 2) visceral adiposity and insulin sensitivity are both unaltered during early adulthood, confirming the predicted developmental trajectory in this animal model. Insulin sensitivity was tested during juvenile development and adipose tissue distribution, adipocyte size, and concentrations of adipokines were determined during early adulthood. Prenatal T-treated females manifested juvenile insulin resistance, which was prevented by prenatal rosiglitazone cotreatment. Neither visceral adiposity nor insulin sensitivity differed between groups during early adulthood. Prenatal T-treated sheep presented an increase in the relative proportion of small adipocytes, which was not substantially prevented by either prenatal intervention. A large effect size was observed for increased leptin concentrations in prenatal T-treated sheep compared with controls, which was prevented by prenatal rosiglitazone. In conclusion, gestational alterations in insulin-glucose homeostasis likely play a role in programming insulin resistance, but not adipocyte size distribution, in prenatal T-treated sheep. Furthermore, these results support the notion that a period of compensatory adaptation of the metabolic system to prenatal T exposure occurs between puberty and adulthood.


Assuntos
Adiposidade/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Resistência à Insulina , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Testosterona/farmacologia , Animais , Modelos Animais de Doenças , Feminino , Flutamida/farmacologia , Obesidade/induzido quimicamente , Obesidade/metabolismo , Obesidade/patologia , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia , Gravidez , Rosiglitazona , Ovinos , Tiazolidinedionas/farmacologia
15.
Endocrinology ; 156(7): 2678-92, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25919188

RESUMO

Prenatal T excess induces maternal hyperinsulinemia, early puberty, and reproductive/metabolic defects in the female similar to those seen in women with polycystic ovary syndrome. This study addressed the organizational/activational role of androgens and insulin in programming pubertal advancement and periovulatory LH surge defects. Treatment groups included the following: 1) control; 2) prenatal T; 3) prenatal T plus prenatal androgen antagonist, flutamide; 4) prenatal T plus prenatal insulin sensitizer, rosiglitazone; 5) prenatal T and postnatal flutamide; 6) prenatal T and postnatal rosiglitazone; and 7) prenatal T and postnatal metformin. Prenatal treatments spanned 30-90 days of gestation and postnatal treatments began at approximately 8 weeks of age and continued throughout. Blood samples were taken twice weekly, beginning at approximately 12 weeks of age to time puberty. Two-hour samples after the synchronization with prostaglandin F2α were taken for 120 hours to characterize LH surge dynamics at 7 and 19 months of age. Prenatal T females entered puberty earlier than controls, and all interventions prevented this advancement. Prenatal T reduced the percentage of animals having LH surge, and females that presented LH surge exhibited delayed timing and dampened amplitude of the LH surge. Prenatal androgen antagonist, but not other interventions, restored LH surges without normalizing the timing of the surge. Normalization of pubertal timing with prenatal/postnatal androgen antagonist and insulin sensitizer interventions suggests that pubertal advancement is programmed by androgenic actions of T involving insulin as a mediary. Restoration of LH surges by cotreatment with androgen antagonist supports androgenic programming at the organizational level.


Assuntos
Antagonistas de Androgênios/farmacologia , Androgênios/farmacologia , Desenvolvimento Fetal/efeitos dos fármacos , Flutamida/farmacologia , Hipoglicemiantes/farmacologia , Metformina/farmacologia , Maturidade Sexual/efeitos dos fármacos , Testosterona/farmacologia , Tiazolidinedionas/farmacologia , Animais , Ciclo Estral/efeitos dos fármacos , Ciclo Estral/metabolismo , Feminino , Hormônio Luteinizante/efeitos dos fármacos , Hormônio Luteinizante/metabolismo , Síndrome do Ovário Policístico , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Rosiglitazona , Ovinos , Carneiro Doméstico
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