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106 results on '"Gioia, Luisa"'

5. Oocyte activation is a cytoplasm-confined event so far: what about the nucleus?

Author

Gioia, Luisa, Palazzese, Luca, Czernik, Marta, Iuso, Domenico, Fulka, Helena, Fulka Jr, Josef, and Loi, Pasqualino

Subjects
OVUM, INTRACYTOPLASMIC sperm injection, REPRODUCTIVE technology, CELL cycle, DOMESTIC animals
Abstract

The fertilizing spermatozoa induce a Ca2+ oscillatory pattern, the universal hallmark of oocyte activation, in all sexually reproducing animals. Assisted reproductive technologies (ARTs) like intracytoplasmic sperm injection (ICSI) bypass the physiological pathway; however, while a normal Ca2+ release pattern occurs in some species, particularly humans, artificial activation is compulsory for ICSI-fertilized oocytes to develop in most farm animals. Unlike the normal oscillatory pattern, most artificial activation protocols induce a single Ca2+ spike, undermining proper ICSIderived embryo development in these species. Curiously, diploid parthenogenetic embryos activated by the same treatments develop normally at high frequencies and implant upon transfer in the uterus. We hypothesized that, at least in ruminant embryos, the oscillatory calcium waves late in the first cell cycle target preferentially the paternal pronucleus and are fundamentally important for paternal nuclear remodeling. We believe that Ca2+ signaling is central to full totipotency deployment of the paternal genome. Research in this area could highlight the asymmetry between the parental genome reprogramming timing/mechanisms in early development and impact ARTs like ICSI and cloning. [ABSTRACT FROM AUTHOR]

Published
2024
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16. L’immunoistochimica, l’immunofluorescenza e la microscopia laser confocale nello studio del sistema nervoso enterico in corso di Scrapie ovina

Author

Marruchella, Giuseppe, Ligios, C., Baffoni, Marina, Cancedda, Mg, Macciocu, S, Gioia, Luisa, Lalatta Costerbosa, G, Chiocchetti, R, Clavenzani, P, De Grossi, L, Agrimi, U, Aguzzi, A, DI GUARDO, Giovanni, MARRUCHELLA G., LIGIOS C., BAFFONI M., CANCEDDA G.M., MACCIOCU S., GIOIA L., LALATTA COSTERBOSA G., CHIOCCHETTI R., CLAVENZANI P., DE GROSSI L., AGRIMI U., AGUZZI A., and DI GUARDO G.

Published
2007

26. Cold-induced calcium elevation triggers DNA fragmentation in immature pig oocytes

Author

Mauro, Mattioli, Barbara, Barboni, Luisa, Gioia, Pasqualino, Loi, and Gioia, Luisa

Subjects
Ruthenium red, Swine, DNA damage, chemistry.chemical_element, DNA Fragmentation, Calcium, Biology, Calcium in biology, chemistry.chemical_compound, BAPTA, Genetics, Animals, Calcium Signaling, Egtazic Acid, Chelating Agents, Ryanodine receptor, Cell Biology, Kinetics, chemistry, Biochemistry, Oocytes, Biophysics, DNA fragmentation, Female, Intracellular, Developmental Biology
Abstract

Fluo-4 loaded immature oocytes were cooled from 30°C to various lower temperatures between 20 and 10°C and changes in intracellular calcium (Ca2+) levels were measured. Pig oocytes cooled to 14°C exhibited a clear biphasic Ca2+ rise. Lower temperatures produced similar responses, while higher temperatures did not exert any effect. The Ca2+ response appeared to rely on ryanodine dependent stores as removal of extracellular Ca2+ and intracytoplasmic injection of heparin did not modify cold-induced Ca2+ elevation, while procaine or ruthenium red virtually eliminated the response. Confocal analysis of subcellular Ca2+ distribution during cooling revealed that the ion rises sharply within the nucleus. As Ca2+ imbalance may activate nuclear endonucleases, DNA integrity of cooled pig oocytes was evaluated by TUNEL and comet assays. Most cooled oocytes showed clear signs of DNA fragmentation. Oocytes injected with 1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetracetic acid tetrapotassium salt (BAPTA), a Ca2+ chelator, maintained their DNA integrity thus confirming that intracellular Ca2+ is involved in triggering DNA fragmentation. The protective effect exerted by ruthenium red and/or procaine further confirmed this hypothesis. These data show that a moderate and transient cooling is sufficient to cause an intracellular Ca2+ rise that leads to DNA damage. The addition of inhibitors of ryanodine dependent Ca2+ stores may represent a valuable protective treatment to reduce chilling injuries. Mol. Reprod. Dev. 65: 289–297, 2003. © 2003 Wiley-Liss, Inc.

Published
2003

28. Preovulatory rise of NGF in ovine follicular fluid: possible involvement in the control of oocyte maturation

Author

Barboni, Barbara, Mattioli, Mauro, Gioia, Luisa, Turriani, Maura, Capacchietti, Giulia, Berardinelli, Paolo, and Bernabo', Nicola

Subjects
Meiosis, Sheep, Oocytes, Animals, Enzyme-Linked Immunosorbent Assay, Female, Nerve Growth Factors, In Vitro Techniques, Chorionic Gonadotropin, Follicular Fluid
Abstract

Since nerve growth factor (NGF) is produced in vitro by granulosa cells after gonadotropin stimulation, the present research has been designed to investigate whether this neurotropin is involved in the events triggered by the gonadotropin surge that lead the follicle to ovulate a mature oocyte. To this aim, NGF levels in follicular fluid, collected before or 20 hours after the gonadotropin surge, was measured by ELISA. To evaluate whether NGF may have a non-neurotropic effect on follicle cells, the presence of NGF receptors was investigated by immunohistochemistry and further evaluated by analysing the tyrosine-phosphorylation pattern after NGF stimulation in vitro. The effect of NGF on the degree of cumulus expansion, cumulus-oocyte metabolic coupling, and meiotic maturation was finally studied by using the culture of follicle-enclosed oocyte. The results demonstrate that GnRH causes a dramatic rise of NGF in large follicles. Immunohistochemistry revealed a discrete positivity for trkA receptors localised in cumulus cells. Tyrosine phosphorylation pattern confirms that somatic cells are capable to transduce NGF signal. By contrast, all the oocytes examined were negative for trkA and did not change the phosphorylation pattern after NGF. In vitro NGF (100 ng/ml) induced a marked cumulus expansion and a progressive cumulus-oocyte uncoupling similar to that produced by gonadotropins. The addition of NGF also caused the resumption of meiosis in more than 70% of the oocytes analysed with an effect that is only slightly less pronounced than that of gonadotropins (80%). The increase in NGF secretion following gonadotropin surge suggests that this neurotropin may be involved in the control of oocyte maturation.

Published
2002

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