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Many studies have demonstrated that oxidative stress-induced apoptosis is a main cause of follicular atresia. Reactive oxygen species (ROS)-induced granulosa cell (GC) apoptosis is regulated by a variety of signaling pathways involving numerous genes and transcription factors. In this study, we found expression of the p53-upregulated modulator of apoptosis (PUMA), a BH3-only Bcl-2 subfamily protein, in ovarian GCs during oxidative stress. By overexpression and knockdown of Forkhead box O1 (FoxO1), we found that FoxO1 regulates PUMA at the protein level. Moreover, as c-Jun N-terminal kinase (JNK) has been shown to activate FoxO1 by promoting its nuclear import, we used a JNK inhibitor to reduce FoxO1 activation and detected decreased PUMA messenger RNA expression and protein levels during oxidative stress. In addition, in vivo oxidative stress-induced upregulation of PUMA was found following injection of 3 nitropropionic acid in mice. In conclusion, oxidative stress increases PUMA expression regulated by FoxO1 in follicular GCs. [ABSTRACT FROM AUTHOR]

Oxidative stress induces many serious reproductive diseases in female mammals and thus poses a serious threat to reproductive health. However, the relationship between reactive oxygen species (ROS)—induced oxidative stress and follicular development, oocyte and embryo quality is not clear. The aim of this study was to investigate the effect of ovarian oxidative stress on the health of follicle and oocyte development. Female ICR mice were dosed with 3-nitropropionic acid (3-NPA) at three different concentrations (6.25, 12.5 and 25 mg/kg) and saline (control) via continuous intraperitoneal injection for 7 days. The treatment with 12.5 mg/kg reduced the weight of mouse ovaries, and significantly increased ROS levels and the activities of antioxidant enzymes—total superoxide dismutase (T-SOD), glutathione peroxidase (GPx) and catalase (CAT) — in granulosa cells and ovarian tissues, but not in other tissues (brain, liver, kidney and spleen). The same treatment significantly increased the percentage of atretic large follicles, and reduced the number of large follicles, the number of ovulated oocytes, and the capacity for early embryonic development compared with controls. It also significantly decreased the ratio of Bcl-2 to Bax, while causing an increase in the mRNA expression of (SOD2, CAT and GPX) and ROS levels in granulosa cells. Collectively, these data indicate that 3-NPA induces granulosa cell apoptosis, large follicle atresia, and an increase of ROS levels in the ovary. Therefore, we have established an in vivo model of ovarian oxidative stress for studying the mechanism of resulting damage induced by free radicals and for the screening of novel antioxidants. [ABSTRACT FROM AUTHOR]

Abstract: Survivin is a member of inhibitors of apoptosis proteins (IAPs), and also belongs to be a member of the chromosomal passenger complex (CPC) which has multiple functions including inhibition of apoptosis and regulation of cell division and SAC activity. Plk1 (polo-like kinase 1) associates with the spindle poles and also distributes to the kinetochores and is shown to involve in spindle organization, APC/C activation and cytokinesis in many models. Our recent work has shown that Survivin is a critical regulator of chromosome segregation and spindle assembly checkpoint (SAC) in meiosis. In the present study, we found that Plk1 co-localized with Survivin at metaphase I (MI) and telophase I (TI) stage after GVBD. Plk1 dispersed into the oocyte cytoplasm or accumulated near the chromosomes after the depletion of Survivin by morpholino (MO) injection. Our results showed that the localization of Plk1 to kinetochores required the involvement of Survivin. [Copyright &y& Elsevier]

Abstract: Cavernous hemangioma is vascular malformation with developmental aberrations. It was assumed that the abnormality of endothelial cells contributed greatly to the occurrence of cavernous hemangioma. In our previous study, we have found distinct characteristics of endothelial cells derived from human liver cavernous hemangioma (HCHEC). Here, we reported the abnormal vascular vessels formed by primary HCHEC in nude mice and that the drug podophyllotoxin can destroy HCHEC in vitro and in vivo. HCHEC was isolated from a human liver cavernous hemangioma specimen, and the HCHEC generated a red hemangioma-like mass 7 days after subcutaneously co-inoculating HCHEC and human liver cancer cells (Bel-7402) in nude mice. Lentiviral expression of GFP and immunohistochemistry for human CD31 was used to confirm that the HCHEC formed the blood vessels in nude mice. And the pathological features of vascular vessels formed by HCHEC were very similar to clinical cavernous hemangioma. In addition, by MTT assay, the drug podophyllotoxin was found inhibiting HCHEC viability, and by TUNEL and DNA ladder assays, podophyllotoxin was found inducing apoptosis of HCHEC. Moreover, podophyllotoxin was also effective for destroying the abnormal vascular vessels in the hemangioma-like mass in nude mice. In summary, the HCHEC can form abnormal blood vessels in nude mice, and we can evaluate drugs for cavernous hemangioma by using HCHEC in vitro and in vivo. [Copyright &y& Elsevier]

Mammalian diaphanous1 (mDia1) is a homologue of Drosophila diaphanous and belongs to the Formin-homology family of proteins that catalyze actin nucleation and polymerization. Although Formin family proteins, such as Drosophila diaphanous, have been shown to be essential for cytokinesis, whether and how mDia1 functions during meiosis remain uncertain. In this study, we explored possible roles and the signaling pathway involved for mDia1 using a mouse oocyte model. mDia1 depletion reduced polar body extrusion, which may have been due to reduced cortical actin assembly. mDia1 and Profilin1 had similar localization patterns in mouse oocytes and mDia1 knockdown resulted in reduced Profilin1 expression. Depleting FMNL1, another Formin family member, resulted in reduced mDia1 expression, while RhoA inhibition did not alter mDia1 expression, which indicated that there was a FMNL1-mDia1-Profilin1 signaling pathway in mouse oocytes. Additionally, mDia1 knockdown resulted in disrupting oocyte spindle morphology, which was confirmed by aberrant p-MAPK localization. Thus, these results demonstrated indispensable roles for mDia1 in regulating mouse oocyte meiotic maturation through its effects on actin assembly and spindle organization. [ABSTRACT FROM AUTHOR]

Most mammalian follicles undergo atresia at various stages before ovulation, and granulosa cell apoptosis is a major cause of antral follicular atresia. Estradiol is an essential mitogen for granulosa cell proliferation in vivo and inhibition of apoptosis. The estradiol-producing capacity and metabolism levels are important for follicle health, and sufficient estradiol is necessary for follicle development and ovulation. Cyp1b1 , a member of the cytochrome P450 1 subfamily, is responsible for the metabolism of a wide variety of halogenated and polycyclic aromatic hydrocarbons in diverse tissues. In mouse follicles, Cyp1b1 converts estradiol to 4-hydroxyestradiol. We investigated mouse granulosa cells (MGCs) in vivo and in vitro and found that Cyp1b1 played a crucial role in estradiol metabolism in dominant follicles. Follicle-stimulating hormone (FSH) decreased estrogen metabolism by reducing Cyp1b1 mRNA and protein levels in MGCs. Furthermore, FSH regulated signal transducer and activator of transcription 1 (STAT1), a significant transcription factor of Cyp1b1 , by mediating the dephosphorylation of STAT1 on serine 727 (Ser 727 ) in MGCs. p38 mitogen-activated protein kinase (MAPK) may be involved in the FSH-induced dephosphorylation of STAT1 on Ser 727 in MGCs. These results suggested that FSH functions via p38 MAPK-induced dephosphorylation at Ser 727 of STAT1 to downregulate Cyp1b1 expression and maintain the estradiol levels in mouse dominant follicles. [ABSTRACT FROM AUTHOR]

Highlights: [•] Amino acid sequence KKRK is responsible for nuclear localization of TET3. [•] Amino acid sequence KKRK are capable of targeting the cytoplasmic proteins to the nucleus. [•] Amino acid sequence KKRK are conserved in TET3 orthologs. [ABSTRACT FROM AUTHOR]