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La stanniocalcina 1 è un potenziale regolatore fisiologico della steroidogenesi nel follicolo ovarico suino.
No full textProlactin is a potential physiological modulator of swine ovarian follicle function.
No full textApart from the well established role of prolactin (PRL) in the control of mammary development and lactation, this hormone appears to possess a variety of physiological functions and evidence exists about its expression in many extra-pituitary sites. This experimental work was undertaken to gain knowledge about PRL and its receptor presence in the porcine antral follicle. In particular, we investigated the expression and local production of PRL in follicular fluid, theca and granulosa cells cultured in standard conditions and in hypoxia. Then, we also investigated its modulatory effect on several parameters mainly involved in granulosa cell function, namely redox status and steroidogenesis. In order to verify an involvement of PRL in the control of ovarian angiogenesis, a process strictly linked to follicle growth and development, we have verified possible PRL effects on granulosa cell production of Vascular Endothelial Growth Factor (VEGF) and nitric oxide as well as its modulatory role on the angiogenic activity of endothelial cells. Our data demonstrate that in the swine PRL is expressed in both components of the antral follicle, theca and granulosa layers, and it is produced by granulosa cells. Moreover, the hormone represents a relevant modulatory factor on key processes underlying follicular growth and development, such as steroidogenesis and angiogenesis
Protein mutations following adaptation of avian influenza viruses in different biological systems
Full text linkTraditionally, embryonated chicken eggs (ECE) are considered the gold standard for Influenza virus isolation and vaccine production. Nowadays, different biological systems have been improved and performed, in order to evaluate a feasible alternative to ECE. In fact, in a previous study, mammalian and avian cell cultures were successfully used for avian influenza viruses primary isolation from target tissues and virus propagation. This research is focused on the investigation of adaptive mutations that occur after influenza A virus amplification in ECE and cell cultures. The results of the study shows that avian influenza viruses after multiple passages in different biological systems undergo mutations, in particular, the largest number of amino acid substitutions occurred in all biological substrates in the hemagglutinin
Gossypol, a polyphenolic aldehyde from cotton plant, interferes with swine granulosa cell function
No full textGossypol is a polyphenol isolated from the seed, roots and stem of cotton plant (Gossypium sp.) It
has been associated with adverse effects on female reproduction, but recently also shown having
promising effects against several malignancies. Its mechanisms of action are however still not fully
understood. This study was therefore conducted to investigate the effect of 5 or 25 microg/mL
gossypol on swine granulosa cell steroidogenic activity, redox status and Vascular Endothelial
Growth Factor (VEGF) production. Study demonstrated that gossypol significantly (P<0.001)
inhibited granulosa cell estradiol 17beta and progesterone production, an effect that could be at least
partially mediated by an increase (P<0.05) of nitric oxide and superoxide anion production as a
consequence of superoxide dismutase inhibition. Moreover, gossypol stimulates (P<0.001) VEGF
production. In conclusion, study has demonstrated effects of gossypol on swine granulosa cell
function in vitro. Effects on female swine fertility can not be exclude
Stanniocalcin 1 affects redox status of swine granulosa cells
No full textStanniocalcin 1 (STC1) is a glycoprotein hormone expressed in different mammalian tissues. In previous studies, we showed STC1 expression in swine ovarian follicles and we demonstrated that STC1 may be a physiological regulator of follicular function. Since reactive oxygen species (ROS) are important signal transducers in the ovary, the present study was undertaken to investigate STC1 action on ROS generation and on the activity of the major enzymatic and non-enzymatic scavengers in swine granulosa cells. O2- generation, catalase activity and FRAP levels were increased by STC1, whereas H2O2 generation and peroxidase activity were decreased by STC1. Taken together, our data show that STC1 modulates redox status in swine granulosa cells
Gelatinases (MMP2 and MMP9) in swine antral follicle
No full textAbstract.Follicular growth is allowed by extracellular matrix (ECM) remodelling and vascular network development. Since matrix metalloproteinases (MMPs) play a crucial role in both of these processes, the aim of the present study was to evaluate the expression of gelatinases MMP2 and MMP9 in swine ovarian follicle (theca and granulosa compartments) during its development. Moreover, we measured gelatinase activities into follicular fluids (FF). Our data demonstrate for the first time that MMP2 and MMP9 are expressed in swine ovarian follicle both in theca and granulosa layers; moreover we show that the expression of both gelatinases increases in theca while decreases in granulosa during follicle growth. Additionally, MMP2 activity has been detected in FF. The spatial pattern of expression of gelatinases in swine follicle suggests a differential role during physiological ovarian events
Netrin-1: Just an axon-guidance factor?
No full textNetrin-1 was first identified as a guidance factor in axon outgrowth during central nervous
system development and was later shown to be involved in the morphogenesis of other
organs. This study, thus, aimed to verify netrin-1 gene expression in swine antral follicles
and to detect netrin-1 protein expression in follicular fluid. In addition, since netrin-1 is also
a potential guidance factor for endothelial cells during angiogenesis, an essential event for
follicular development, we attempted to verify its effects on swine aortic endothelial cells.
Our results show that netrin-1 is present in follicular fluid and is physiologically expressed
in both the thecal and granulosa layers from swine antral follicles. Furthermore, by means
of an angiogenesis bioassay, we documented the inhibition of vascular neoformation by
netrin-1. In conclusion, our results demonstrate that netrin-1 can be synthesized by swine
follicular cells and secreted in the follicular fluid where it appears to exert regulatory effects
on both follicular function and vascular development
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