L. Gioia
University of Teramo, Biomedical Sciences, Faculty Member
Research Interests:
The research has been designed to investigate whether acrosome-reacted spermatozoa can fuse with somatic cells and to check whether this event may involve the molecular machinery implicated in the sperm–egg fusion. Boar spermatozoa were... more
The research has been designed to investigate whether acrosome-reacted spermatozoa can fuse with somatic cells and to check whether this event may involve the molecular machinery implicated in the sperm–egg fusion. Boar spermatozoa were capacitated in vitro and then treated with A23187 to induce acrosome reaction and activate their fusogenic potential. Reacted spermatozoa, loaded with the membrane-permeant fluorescent dye calcein AM, were incubated with plated granulosa cells or cells derived from stable cell lines: CRFK, VERO, and ESK4. The fusion between spermatozoa and somatic cells was revealed by the diffusion of the fluorescent dye from the sperm to the cell as membrane fusion and cytoplasmic continuity between the two cells were established. The involvement of integrin α6 and tetraspanin CD9 in the process of fusion was assessed by carrying out the experiment in the presence of antibodies against these molecules. Moreover, the incidence of fusion displayed by the different ce...
Research Interests: Physiology, Reproduction, Cats, Cercopithecus aethiops, Cell line, and 15 moreHumans, Cell fusion, Female, Animals, Male, Clinical Sciences, Hybrid Solar Cells, Swine, Cell communication, Spermatozoa, Acrosome Reaction, Vero cells, Somatic Cells, Sperm capacitation, and Paediatrics and reproductive medicine
Research Interests: Physiology, Biology, Medicine, Oogenesis, Female, and 15 moreAnimals, In Vitro Fertilization, Male, DNA methylation, Enzyme, Clinical Sciences, Oocyte Maturation, Histones, Fluorescent Antibody Technique, Fertility Rate, Acetylation, Fertilization in Vitro, Histone Acetylation, Histone deacetylases, and Paediatrics and reproductive medicine
Research Interests:
Research Interests:
Research Interests:
... Later other neurotrophic factors were found and charac-terised, including BDNF (Leibrock et al, 1989; Hyman et al, 1991; Knusel et al, 1991), NT-3 ... As far as the ovary is concerned, both NGF and its mRNA have been detected in the... more
... Later other neurotrophic factors were found and charac-terised, including BDNF (Leibrock et al, 1989; Hyman et al, 1991; Knusel et al, 1991), NT-3 ... As far as the ovary is concerned, both NGF and its mRNA have been detected in the immature rat ovary (Lara et al, 1990a), and ...
Research Interests:
We have studied the changes in membrane potential induced by LH in cumulus and granulosa cells isolated from sheep antral follicles. The investigation was carried out by using a non-invasive technique based on the use of a membrane... more
We have studied the changes in membrane potential induced by LH in cumulus and granulosa cells isolated from sheep antral follicles. The investigation was carried out by using a non-invasive technique based on the use of a membrane potential sensitive probe, bis-oxonol. The membrane potential of mural granulosa cells was totally unaffected by LH, while that of cumulus or corona cells showed a marked depolarisation, starting 2-3 min after the addition of the hormone and plateauing after 5-10 min. None of the cells tested reacted to FSH. In the second part of the experiment the role of protein kinase A (PKA) and protein kinase C (PKC) in mediating the effect of LH was studied. The selective activation of PKA or PKC induced in cumulus-corona cells a rapid hyperpolarisation due to increased Cl and K conductance respectively. By contrast, the simultaneous activation of the two kinases induced a rapid membrane depolarisation due to the progressive decrease in K conductance. The activation of each kinase or their combined stimulation did not induce any change in the membrane potential of mural granulosa cells. These data demonstrated that LH has a depolarising effect regionally circumscribed to cumulus-corona cells and that this depolarisation depends on a reduction of K conductance caused by the activation of PKA and PKC.
Research Interests:
Vascular endothelial growth factor (VEGF) expression pattern and blood vessel remodelling were evaluated during the transition from the preovulatory follicle to the corpus luteum (CL). To this end, prepubertal gilts were treated with... more
Vascular endothelial growth factor (VEGF) expression pattern and blood vessel remodelling were evaluated during the transition from the preovulatory follicle to the corpus luteum (CL). To this end, prepubertal gilts were treated with equine chorionic gonadotrophin (eCG) to collect preovulatory follicles (60 h after eCG) and with human chorionic gonadotrophin (hCG) to obtain periovulatory follicles 18 h and 36 h later. The VEGF mRNA content was analysed by in situ hybridization, while protein localization in follicular fluid (FF) and in granulosa and theca compartments was evaluated by ELISA, immunohistochemistry or western blot. Blood vessel architecture and vascular area (VA) were investigated using immunohistochemistry for von Willenbrand Factor, a specific endothelial marker. Vascular remodelling was finally tested using Ki-67 immunocytochemistry as a proliferation marker, or alpha-smooth muscle actin (alpha-SMA) as a specific mural cell marker. eCG-treated follicles showed high VEGF levels and two concentric blood vessel networks composed of proliferating endothelial cells without any association with mural components. hCG injection inhibited VEGF synthesis in the granulosa compartment and, as a consequence, the protein fell within the FF. In parallel, endothelial cell proliferation stopped and the VA decreased. Close to ovulation, VEGF production restarted in both follicular compartments and VEGF mRNA content significantly increased in the theca layer. Changes in follicular VEGF secretion were observed; the protein disappeared from FF and was observed in the extracellular matrix. An active angiogenesis characterized the follicle; endothelial cell proliferation was associated with a recruitment of alpha-SMA-positive mural cells. The data presented in this work showed that, in the phases preceding ovulation, a complete vascular remodelling occurs, characterized by both an evident neovascularization and the appearance of blood vessels presenting smooth musculature which could be involved in CL formation after ovulation.