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1.
Endocrinology ; 161(2)2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32020188

RESUMO

Polycystic ovary syndrome (PCOS) is associated with hyperandrogenism, and we previously found that androgens activate endoplasmic reticulum (ER) stress in granulosa cells from patients with PCOS. In addition, recent studies demonstrated the accumulation of advanced glycation end products (AGEs) in granulosa cells from PCOS patients, which contribute to the pathology. Therefore, we hypothesized that androgens upregulate the receptor for AGEs (RAGE) expression in granulosa cells by activating ER stress, thereby increasing the accumulation of AGEs in these cells and contributing to the pathology. In the present study, we show that testosterone increases RAGE expression and AGE accumulation in cultured human granulosa-lutein cells (GLCs), and this is reduced by pretreatment with tauroursodeoxycholic acid (TUDCA), an ER stress inhibitor in clinical use. Knockdown of the transcription factor C/EBP homologous protein (CHOP), an unfolded protein response factor activated by ER stress, inhibits testosterone-induced RAGE expression and AGE accumulation. The expression of RAGE and the accumulation of AGEs are upregulated in granulosa cells from PCOS patients and dehydroepiandrosterone-induced PCOS mice. Administration of the RAGE inhibitor FPS-ZM1 or TUDCA to PCOS mice reduces RAGE expression and AGE accumulation in granulosa cells, improves their estrous cycle, and reduces the number of atretic antral follicles. In summary, our findings indicate that hyperandrogenism in PCOS increases the expression of RAGE and accumulation of AGEs in the ovary by activating ER stress, and that targeting the AGE-RAGE system, either by using a RAGE inhibitor or a clinically available ER stress inhibitor, may represent a novel approach to PCOS therapy.


Assuntos
Estresse do Retículo Endoplasmático , Produtos Finais de Glicação Avançada/metabolismo , Células da Granulosa/metabolismo , Hiperandrogenismo/metabolismo , Síndrome do Ovário Policístico/etiologia , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Animais , Benzamidas/uso terapêutico , Estudos de Casos e Controles , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Camundongos Endogâmicos BALB C , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/metabolismo , Ácido Tauroquenodesoxicólico/uso terapêutico , Testosterona
2.
J Obstet Gynaecol Res ; 46(2): 302-309, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31922309

RESUMO

AIM: The cryopreservation of embryos is essential for assisted reproductive technology field. The aim of the present study is to examine the efficacy and ease of use of a new vitrification device, Kitasato Vitrification System (KVS), in cryopreservation of human embryos. METHODS: Human embryos at the cleavage or blastocyst stage were vitrified and warmed by KVS or Cryotop (control device). The survival of cleavage- and blastocyst-stage embryos and the developmental competence of cleavage-stage embryos were evaluated. Four individuals inexperienced in vitrification and warming embryos tested both KVS and Cryotop. The vitrification time and the detachment time of the embryos were evaluated. RESULTS: At the cleavage stage, there were no significant differences in the survival rate and the development rate to the blastocyst stage between KVS and Cryotop (100 vs 96.8% and 63.3 vs 61.3%, respectively). At the blastocyst stage, there was no significant difference in the re-expansion rate between KVS and Cryotop (100 vs 88.9%). The vitrification time was shorter for KVS than Cryotop. There was no significant difference in the detachment time between KVS and Cryotop. CONCLUSION: Kitasato Vitrification System is easy to operate, even for inexperienced users, and the viability of human embryos vitrified by KVS is comparable to that of Cryotop, a widely used vitrification device.


Assuntos
Criopreservação/instrumentação , Embrião de Mamíferos , Vitrificação , Adulto , Desenvolvimento Embrionário , Feminino , Humanos
3.
Mol Hum Reprod ; 26(1): 40-52, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31869409

RESUMO

Endometriosis exerts detrimental effects on ovarian physiology and compromises follicular health. Granulosa cells from patients with endometriosis are characterized by increased apoptosis, as well as high oxidative stress. Endoplasmic reticulum (ER) stress, a local factor closely associated with oxidative stress, has emerged as a critical regulator of ovarian function. We hypothesized that ER stress is activated by high oxidative stress in granulosa cells in ovaries with endometrioma and that this mediates oxidative stress-induced apoptosis. Human granulosa-lutein cells (GLCs) from patients with endometrioma expressed high levels of mRNAs associated with the unfolded protein response (UPR). In addition, the levels of phosphorylated ER stress sensor proteins, inositol-requiring enzyme 1 (IRE1) and double-stranded RNA-activated protein kinase-like ER kinase (PERK), were elevated in granulosa cells from patients with endometrioma. Given that ER stress results in phosphorylation of ER stress sensor proteins and induces UPR factors, these findings indicate that these cells were under ER stress. H2O2, an inducer of oxidative stress, increased expression of UPR-associated mRNAs in cultured human GLCs, and this effect was abrogated by pretreatment with tauroursodeoxycholic acid (TUDCA), an ER stress inhibitor in clinical use. Treatment with H2O2 increased apoptosis and the activity of the pro-apoptotic factors caspase-8 and caspase-3, both of which were attenuated by TUDCA. Our findings suggest that activated ER stress induced by high oxidative stress in granulosa cells in ovaries with endometrioma mediates apoptosis of these cells, leading to ovarian dysfunction in patients with endometriosis.


Assuntos
Apoptose/genética , Endometriose/genética , Estresse do Retículo Endoplasmático/genética , Endorribonucleases/genética , Proteínas Serina-Treonina Quinases/genética , eIF-2 Quinase/genética , Adulto , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Caspase 8/genética , Caspase 8/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Endometriose/metabolismo , Endometriose/patologia , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Endorribonucleases/metabolismo , Feminino , Regulação da Expressão Gênica , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Células da Granulosa/patologia , Humanos , Peróxido de Hidrogênio/farmacologia , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ovário/patologia , Estresse Oxidativo , Cultura Primária de Células , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Ácido Tauroquenodesoxicólico/farmacologia , Resposta a Proteínas não Dobradas , eIF-2 Quinase/metabolismo
4.
J Obstet Gynaecol Res ; 44(10): 1956-1962, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30004618

RESUMO

AIM: The objective of this study is to determine the factors associated with successful pregnancy in women of late reproductive age with uterine fibroids who undergo embryo cryopreservation before surgery (ECBS). METHODS: Patients who underwent in vitro fertilization treatment with controlled ovarian stimulation from November 2010 to January 2017 in our university hospital were included. Twenty-two patients older than 35 years of age at the first visit with cavity-distorting uterine fibroids underwent ECBS, a three-step therapeutic approach consisting of oocyte pick-up, myomectomy and embryo transfer (ET), which are performed in this order. We retrospectively calculated the pregnancy rate and determined the factors associated with successful pregnancy. RESULTS: The mean age at ET of the patients who underwent ECBS was 40.9 years, with a pregnancy rate per ET of 36.8% (21/57). Of 22 patients, 10 (45.5%) successfully continued pregnancy beyond 12 weeks of gestation (ongoing pregnancy). An ongoing pregnancy was observed only among the patients with more than three frozen embryos. The ongoing pregnancy rates of patients with ≤five fibroids and ≤5 cm in the maximal diameter were significantly higher compared to the respective remaining group (90.0% vs 14.3% and 87.5% vs 33.3%). CONCLUSION: ECBS is an effective strategy for infertile women of late reproductive age with cavity-distorting uterine fibroids, especially when it is applied to the patients who can freeze at least three embryos before myomectomy, with five or less fibroids smaller than 5 cm in the maximal diameter.


Assuntos
Criopreservação , Transferência Embrionária , Preservação da Fertilidade , Fertilização in vitro , Infertilidade Feminina/cirurgia , Leiomioma/cirurgia , Idade Materna , Recuperação de Oócitos , Avaliação de Resultados em Cuidados de Saúde , Neoplasias Uterinas/cirurgia , Adulto , Feminino , Humanos , Gravidez , Miomectomia Uterina
5.
Gynecol Endocrinol ; 29(2): 113-5, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22835092

RESUMO

Although assisted reproductive technology (ART) is suspected to increase the risk of placenta previa, a life-threatening complication of pregnancy, the reason is poorly understood. We recruited consecutive 318 pregnancies conceived by ART in our clinic and examined relation of ten variables, i.e. maternal age, gravidity, parity, male or female fetus, previous abortion, previous cesarean delivery, endometriosis, ovulatory disorder, tubal disease, and male infertility, to placenta previa, by logistic regression analysis. As a result, we found that endometriosis (odds ratio = 15.1; 95% CI = 7.6-500.0) and tubal disease (odds ratio = 4.4; 95% CI = 1.1-26.3) were significantly associated with placenta previa. It would be preferable to take the increased risk of placenta previa into account in treating ART pregnancy with endometriosis and tubal disease.


Assuntos
Endometriose/fisiopatologia , Doenças das Tubas Uterinas/fisiopatologia , Fertilização in vitro , Infertilidade Feminina/terapia , Placenta Prévia/etiologia , Injeções de Esperma Intracitoplásmicas , Adulto , Características da Família , Feminino , Fertilização in vitro/efeitos adversos , Seguimentos , Hospitais Universitários , Humanos , Infertilidade Feminina/etiologia , Infertilidade Masculina/fisiopatologia , Japão/epidemiologia , Modelos Logísticos , Masculino , Placenta Prévia/diagnóstico por imagem , Placenta Prévia/epidemiologia , Gravidez , Estudos Retrospectivos , Fatores de Risco , Injeções de Esperma Intracitoplásmicas/efeitos adversos , Ultrassonografia Pré-Natal
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