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1.
Reprod Biol Endocrinol ; 15(1): 56, 2017 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-28738839

RESUMO

BACKGROUND: We and others have observed that young girls predisposed to polycystic ovary syndrome (PCOS) display defective insulin sensitivity, beta-cell function and non-esterified fatty acids (NEFA) suppressibility during early pubertal years, compared to controls. Our objective is to assess whether these differences in glucose and NEFA metabolisms persist after 5 years in late/post-puberty. METHODS: We conducted a prospective cohort study between 2007 and 2015 with 4-6 years of follow-up in an academic institution research center. We compared 8 daughters and sisters of PCOS women (PCOSr) to 8 age-matched girls unrelated to PCOS (±1.5 years). Girls were assessed initially at 8-14 years old and re-assessed after a median follow-up of 5.4 years, at 13-21 years old. Our main measures were a frequently sampled intravenous glucose tolerance test (FSivGTT)-derived insulin sensitivity (IS) and beta-cell function (disposition index, DIFSivGTT); and indices of NEFA suppression during FSivGTT (logn-linear slope of NEFA and T50 of NEFA suppression). RESULTS: At follow-up, both PCOSr and controls had similar results: IS = 3.2 vs 3.4 (p = 0.88), DIFSivGTT = 1926 vs 1380 (p = 0.44), logn-linear slope = -0.032 vs -0.032 (p = 0.88) and T50NEFA = 18.1 vs 20.8 min (p = 0.57). IS, DIFSivGTT and NEFA suppressibility were stable in PCOSr after 5 years, but decreased significantly in controls (all p < 0.05). CONCLUSIONS: Impaired metabolism observed during early puberty in girls predisposed to PCOS remains stable after 5 years whereas control girls deteriorated their metabolic parameters. Therefore, both groups become comparable in late/post-puberty. Early puberty may thus represent a window during which metabolic alterations are transiently apparent in girls at risk of PCOS.


Assuntos
Resistência à Insulina , Síndrome do Ovário Policístico/metabolismo , Puberdade Precoce/metabolismo , Adolescente , Ácidos Graxos não Esterificados/metabolismo , Feminino , Seguimentos , Glucose/metabolismo , Homeostase , Humanos , Adulto Jovem
2.
Endocrinology ; 155(9): 3684-93, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24971613

RESUMO

Polycystic ovary syndrome (PCOS) is mainly defined by hyperandrogenism but is also characterized by insulin resistance (IR). Studies showed that overexposure of nonadipose tissues to nonesterified fatty acids (NEFA) may explain both IR and hyperandrogenism. Recent studies indicate that treatment with an angiotensin II type 2 receptor (AT2R)-selective agonist improves diet-induced IR. We thus hypothesized that PCOS hyperandrogenism is triggered by ovarian NEFA overexposure and is improved after treatment with an AT2R agonist. Experiments were conducted in 12-week-old female JCR:LA-cp/cp rats, which are characterized by visceral obesity, IR, hyperandrogenism, and polycystic ovaries. Control JCR:LA +/? rats have a normal phenotype. Rats were treated for 8 days with saline or the selective AT2R agonist C21/M24 and then assessed for: 1) fasting testosterone, NEFA, and insulin levels; and 2) an iv 14(R,S)-[(18)F]fluoro-6-thia-heptadecanoic acid test to determine NEFA ovarian tissue uptake (Km). Compared with controls, saline-treated PCOS/cp rats displayed higher insulin (100 vs 5.6 µU/mL), testosterone (0.12 vs 0.04 nmol/L), NEFA (0.98 vs 0.48 mmol/L), and Km (20.7 vs 12.9 nmol/g·min) (all P < .0001). In PCOS/cp rats, C21/M24 did not significantly improve insulin or NEFA but normalized testosterone (P = .004) and Km (P = .009), which were strongly correlated together in all PCOS/cp rats (ρ = 0.74, P = .009). In conclusion, in an obese PCOS rat model, ovarian NEFA uptake and testosterone levels are strongly associated and are both significantly reduced after short-term C21/M24 therapy. These findings provide new information on the role of NEFA in PCOS hyperandrogenemia and suggest a potential role for AT2R agonists in the treatment of PCOS.


Assuntos
Ácidos Graxos/metabolismo , Hiperandrogenismo/metabolismo , Obesidade/metabolismo , Ovário/metabolismo , Síndrome do Ovário Policístico/metabolismo , Receptor Tipo 2 de Angiotensina/metabolismo , Animais , Feminino , Humanos , Hiperandrogenismo/complicações , Hiperandrogenismo/genética , Insulina/sangue , Resistência à Insulina , Obesidade/complicações , Obesidade/genética , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/genética , Ratos , Ratos Transgênicos , Receptor Tipo 2 de Angiotensina/agonistas , Receptor Tipo 2 de Angiotensina/genética , Testosterona/sangue , Regulação para Cima
3.
Hypertens Pregnancy ; 31(3): 357-66, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21174572

RESUMO

OBJECTIVES: We hypothesized that hydrogen peroxide (H(2)O(2)) and soluble TNF-α receptor 2 (sTNF-R2) co-play a role in the pathogenesis of preeclampsia. METHODS: Correlation of H(2)O(2) and sTNF-R2 was assessed in vivo in maternal blood and placenta, and in vitro in cytotrophoblasts culture. RESULTS: We showed a positive correlation between increased levels of H(2)O(2) and sTNF-R2 early at 10-15 gestational weeks and at term in maternal serum, and in placenta of women with preeclampsia. Our in vitro experiments showed that H(2)O(2) induced the placental synthesis of sTNF-R2. CONCLUSION: We propose to consider H(2)O(2) and sTNF-R2 as potential biomarkers in predicting preeclampsia.


Assuntos
Peróxido de Hidrogênio/sangue , Pré-Eclâmpsia/sangue , Receptores Tipo II do Fator de Necrose Tumoral/sangue , Adulto , Biomarcadores/sangue , Feminino , Humanos , Placenta/metabolismo , Gravidez , Estudos Prospectivos , Adulto Jovem
4.
Reprod Toxicol ; 31(4): 528-33, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21338670

RESUMO

Pesticides associated to genetically modified foods (PAGMF), are engineered to tolerate herbicides such as glyphosate (GLYP) and gluphosinate (GLUF) or insecticides such as the bacterial toxin bacillus thuringiensis (Bt). The aim of this study was to evaluate the correlation between maternal and fetal exposure, and to determine exposure levels of GLYP and its metabolite aminomethyl phosphoric acid (AMPA), GLUF and its metabolite 3-methylphosphinicopropionic acid (3-MPPA) and Cry1Ab protein (a Bt toxin) in Eastern Townships of Quebec, Canada. Blood of thirty pregnant women (PW) and thirty-nine nonpregnant women (NPW) were studied. Serum GLYP and GLUF were detected in NPW and not detected in PW. Serum 3-MPPA and CryAb1 toxin were detected in PW, their fetuses and NPW. This is the first study to reveal the presence of circulating PAGMF in women with and without pregnancy, paving the way for a new field in reproductive toxicology including nutrition and utero-placental toxicities.


Assuntos
Aminobutiratos/farmacocinética , Sangue Fetal/metabolismo , Alimentos Geneticamente Modificados , Glicina/análogos & derivados , Exposição Materna , Praguicidas/farmacocinética , Adulto , Aminobutiratos/efeitos adversos , Aminobutiratos/sangue , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/sangue , Biotransformação , Endotoxinas/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Glicina/efeitos adversos , Glicina/sangue , Glicina/farmacocinética , Proteínas Hemolisinas/sangue , Humanos , Recém-Nascido , Troca Materno-Fetal , Compostos Organofosforados/sangue , Praguicidas/efeitos adversos , Praguicidas/sangue , Ácidos Fosfóricos/sangue , Gravidez , Propionatos/sangue , Quebeque , Glifosato
5.
J Obstet Gynaecol Res ; 34(4): 504-11, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18937704

RESUMO

AIM: Supplementation with antioxidant vitamins has been proposed to reduce the risk of preeclampsia and perinatal complications. In a recent study, it has been shown that this supplementation to above physiological doses does not reduce the risk of preeclampsia, but increases the rate of low birthweight babies, suggesting a detrimental effect on placental function, given the lower birthweight. The aim of the present study was to investigate the effects of high levels of antioxidants vitamins C and E on placental cells in vitro. METHODS: Isolated fresh human cytotrophoblasts were exposed to high concentrations of vitamins C and E for 48 h. Then the secretion of human chorionic gonadotropin (hCG) and the production of tumor necrosis factor-alpha (TNF-alpha) were assessed. RESULTS: High levels of vitamins C and E, separately or combined, decrease the secretion of hCG by cytotrophoblasts and increase their production of TNF-alpha. CONCLUSION: Exposure of cytotrophoblasts to high levels of antioxidant vitamins C and E may affect placental function, as reflected by decreased secretion of hCG; and placental immunity, as reflected by increased production of TNF-alpha. Such alterations are known to lead to endothelial dysfunction and adverse pregnancy outcomes, such as fetal growth restriction (FGR).


Assuntos
Antioxidantes/efeitos adversos , Ácido Ascórbico/efeitos adversos , Placenta/efeitos dos fármacos , Vitamina E/efeitos adversos , Adulto , Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Gonadotropina Coriônica/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Recém-Nascido , Gravidez , Trofoblastos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/biossíntese , Vitamina E/administração & dosagem
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