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1.
Reprod Med Biol ; 22(1): e12529, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37546178

RESUMO

Purpose: Since the developmental competence of oocytes cultured after in vitro maturation (IVM) is low, it is necessary to improve the IVM method for efficient offspring production. In this study, we revealed that transferrin (TF)-Fe3+ was accumulated in follicular fluid with increasing the follicular diameter, and that TF receptor (TFR1) was localized in granulosa cells of pig. Thus, we hypothesized that TF-Fe3+ would be a factor in the induction of developmental competence of porcine oocytes. Methods: To mimic the follicular development environment, cumulus-oocyte complexes (COCs) were cultured in pre-IVM medium (low dose of FSH) without or with Holo-TF (monoferric or diferric TF) or Apo-TF (non-iron bond TF). After pre-IVM without or with Holo-TF, COCs were cultured in IVM medium (high dose of FSH and EGF) without or with Holo-TF. Results: Cultivation with Holo-TF increased the expression of follicular development maker (Cyp19a1 and Ccnd2), E2 production, and proliferative activity of cumulus cells, whereas cultivation with Apo-TF did not show these positive effects. The treatment with Holo-TF during pre-IVM, but not during IVM, dramatically induced oocyte maturation with increasing the blastocyst rate. Conclusion: We succeeded in showing for the first time that the cultivation with Holo-TF in pre-IVM can produce embryos in pig with high efficiency.

2.
Reprod Biol ; 23(1): 100710, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36470010

RESUMO

Postpartum endometritis is known to be associated with ovarian dysfunction in cows. Lipopolysaccharide (LPS) generated by Gram-negative bacteria is recognized by toll-like receptor 4 (TLR4), which leads to an inflammatory response by the generation of cytokines such as tumor necrosis factor-α (TNF-α) and interleukins. In this study, we investigated the effect of endometrial LPS on granulosa cell functions during early follicular development in cows. Uteri and follicles were obtained from a slaughterhouse and classified into either clinical endometritis (CE) or normal groups by vaginal mucus test. TLR4 mRNA and protein in normal cows were expressed in granulosa cells collected from follicles measuring 1-3 and 4-7 mm in a diameter, respectively. LPS content in endometrium and follicular fluid of CE cows was significantly higher than that in normal cows. Compared to normal cows, CE cows showed lower expression of follicular development markers (FSHR, CYP19A1, CCND2, and LHCGR) in granulosa cells, lower estradiol-17ß concentrations in follicular fluid, and lower granulosa cell proliferation. CE contraction significantly increased cytokine expressions (TNF, IL-1A, and IL-1B) in granulosa cells and suppressed apoptosis of granulosa cells compared to normal cows. LPS significantly suppressed the expression of follicular development markers and the production of estradiol-17ß in granulosa cells and reduced granulosa cells proliferation compared to cells cultured without LPS. LPS significantly increased cytokine expressions and suppressed granulosa cell apoptosis. Thus, the present results suggest that the existence of LPS in developing follicles is one of the causes of ovarian quiescence in cows.


Assuntos
Endometrite , Lipopolissacarídeos , Feminino , Humanos , Bovinos , Animais , Lipopolissacarídeos/farmacologia , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Citocinas/metabolismo , Endometrite/metabolismo , Células da Granulosa , Estradiol/metabolismo , Proliferação de Células
3.
Endocrinology ; 162(11)2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34431998

RESUMO

In the liver, the sterol response element binding protein (SREBP) and the SREBP cleavage-activated protein (SCAP) complex upregulate cholesterol biosynthesis by gene induction of de novo cholesterol synthetic enzymes (Hmgcr, Cyp51, and Dhcr7). Insulin induced gene 1 (INSIG1) negatively regulates cholesterol biosynthesis by the inhibition of de novo cholesterol biosynthetic gene expression. In the ovary, cholesterol is de novo synthesized; however, the roles of SREBP and its regulators (SCAP and INSIG1) are not well understood. In this study, when immature mice were treated with gonadotropins (eCG followed by hCG), eCG induced and hCG maintained the expression of SREBP-1a, -2, and SCAP granulosa cells, whereas INSIG1 expression was dramatically downregulated after hCG injection. Downregulation of INSIG1 led to generate the SREBPs active form and translocate the SREBPs active form to nuclei. Inhibition of generation of the SREBPs active form by fatostatin or Scap siRNA in both in vivo and in vitro significantly decreased the expressions of de novo cholesterol biosynthetic enzymes, cholesterol accumulation, and progesterone (P4) production compared with the control group. Fatostatin treatment inhibited the ovulation and increased the formation of abnormal corpus luteum which trapped the matured oocyte in the corpus luteum; however, the phenomenon was abolished by P4 administration. The results showed that decreasing INSIG1 level after hCG stimulation activated SREBP-induced de novo cholesterol biosynthesis in granulosa cells of preovulatory follicles, which is essential for P4 production and the rupture of matured oocyte during ovulation process.


Assuntos
Colesterol/biossíntese , Células da Granulosa/efeitos dos fármacos , Hormônio Luteinizante/farmacologia , Ovulação/efeitos dos fármacos , Animais , Células Cultivadas , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Células da Granulosa/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Redes e Vias Metabólicas/efeitos dos fármacos , Redes e Vias Metabólicas/genética , Camundongos , Camundongos Endogâmicos C57BL , Ovulação/metabolismo , Proteínas de Ligação a Elemento Regulador de Esterol/genética , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo
4.
Open Heart ; 5(2): e000865, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30245838

RESUMO

Objective: Mountain districts normally have tougher geographic conditions than plain districts, which might worsen heart failure (HF) conditions in patients. Also, those places frequently are associated with social problems of ageing, underpopulation and fewer medical services, which might cause delay in detection of disease progression and require more admissions. We investigated the association of residence altitude with readmission in patients with HF. Methods: We followed 452 patients with HF to determine all-cause readmissions over a median of 1.1 years. The altitude of patient residences, population, proportion of the elderly and number of hospitals or clinics in a minor administrative district (Cho-Aza district) located at the residences were examined using data from the 2010 census and Google Maps. Results: All-cause readmissions were observed in 269 (60%) patients. The altitude of ≥200 m was significantly associated with readmissions (HR, 1.49; 95 % CI 1.12 to 1.96; p=0.006) after adjustment for physical and haemodynamic parameters, left ventricular ejection fraction, brain natriuretic peptide and components of the established score for predicting readmission for HF. Altitude was significantly associated with ageing, underpopulation, fewer hospitals or clinics and lower temperature (all p<0.01), with an increased tendency for readmission during the winter season; however, it was not associated with patient clinical parameters. Conclusions: High altitude residence may be an important predictor for readmission in patients with HF. This relationship may be confounded by unfavourable sociogeographic conditions at higher altitudes.

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