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Female fertility and environmental pollution
Full text linkA realistic picture of our world shows that it is heavily polluted everywhere. Coastal regions and oceans are polluted by farm fertilizer, manure runoff, sewage and industrial discharges, and large isles of waste plastic are floating around, impacting sea life. Terrestrial ecosystems are contaminated by heavy metals and organic chemicals that can be taken up by and accumulate in crop plants, and water tables are heavily contaminated by untreated industrial discharges. As deadly particulates can drift far, poor air quality has become a significant global problem and one that is not exclusive to major industrialized cities. The consequences are a dramatic impairment of our ecosystem and biodiversity and increases in degenerative or man-made diseases. In this respect, it has been demonstrated that environmental pollution impairs fertility in all mammalian species. The worst consequences are observed for females since the number of germ cells present in the ovary is fixed during fetal life, and the cells are not renewable. This means that any pollutant affecting hormonal homeostasis and/or the reproductive apparatus inevitably harms reproductive performance. This decline will have important social and economic consequences that can no longer be overlooked
XIV workshop on the development and function of reproductive organs
No full textThe XIV Workshop on the Development and Function of Reproductive Organs was held in Rome, from 14-17 September, 2008, at the Congress Centre of the University of Tor Vergata of Villa Mondragone (Rome, Italy). The Workshop was conceived to be a survey of the events from the formation of the gamete precursors, the primordial germ cells, to the development of the preimplantation embryo through female and male gametogenesis in the mouse experimental model. It was divided into six topics including classic and highly-debated current subjects in the field of the biology of reproduction: mammalian primordial germ cells, the formation of the gonads, stem cells and germ cells, gametogenesis from birth to adult (male), gametogenesis from birth to adult (female), and finally fertilization and preimplantation embryo
Effect of PACAP and VIP on mouse preantral follicle development in vitro
No full textPituitary adenylate cyclase-activating polypeptide (PACAP) is a bioactive peptide isolated from ovine hypothalamus. It is transiently expressed in preovulatory follicles and positively affects several parameters correlated with the ovulatory process. It has also been shown to be expressed in the interstitial tissue around primordial and preantral follicles. The aim of the present study was to investigate whether PACAP influences preantral follicle growth and differentiation. Mouse preantral follicles were cultured for 5 d in the presence of FSH and increasing concentrations of PACAP or vasoactive intestinal polypeptide (VIP) (10(-12) to 10(-7) m). In the presence of FSH, follicles increased in diameter and formed an antrum. At the concentrations tested, neither PACAP alone nor VIP alone had any effect on follicle development, but the addition of either peptide to FSH-stimulated follicles caused a dose-dependent inhibition of follicle growth, antrum formation, granulosa cell proliferation, and estradiol production. The effect of PACAP on follicle growth and antrum formation was directly correlated with the length of stimulation and was reversible. Although exposure of follicles to 10(-7) m PACAP and VIP did not affect oocyte growth, it severely impaired completion of meiotic maturation in oocytes isolated from the follicles and cultured for 17 h in medium alone. The cyclic production of PACAP by preovulatory follicles during the estrous cycle in adult rats and its induction by LH in the rat and mouse ovary suggest that this peptide may play a role in the local regulation of preantral follicle growth
Granulosa cell-oocyte interactions
No full textThroughout oogenesis the oocyte and follicle cells establish an intricate system
of mutual interactions that ultimately lead to the acquisition of their
respective competences. Paracrine factors released by both cell types are
believed to stimulate formation of the primordial follicle and support the
initial phases of follicle growth. At the same time, these processes are also
dependent on gap junction communication between the germinal and somatic
compartment. At later stages of follicle development, activities released by the
oocyte induce the adjacent granulosa cells to express a specialized phenotype. In
their turn, these cells crucially regulate the ability of the oocyte to progress
through the meiotic process and acquire full developmental potentia
Epithelium-Mesenchyme interactions mediated by HGF/HGFR system during the late fetal period of mouse testis development
No full textInvolvement of carbohydrates in the hardening of the zona pellucida of mouse oocytes
No full textThe effect of lectins with different saccharide specificity (ConA, LCA, DBA, WGA and PNA) on enzymatic digestion of the zona pellucida (ZP) of mouse oocytes was studied. All lectins tested, except PNA, induced ZP hardening with different degrees of efficiency. Moreover, extensive ZP digestion with mixed exoglycosidase prevented "spontaneous" ZP hardening. These observations suggest that changes of the carbohydrate moieties can be involved in the hardening of the zona pellucida of mouse oocytes
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