Gonadotropin Cell Transduction Mechanisms

The intention of this Special Edition was to collect review and original research articles that illustrate and stimulate the growing efforts to highlight the mechanisms of action of gonadotropins, as well as deepen our understanding of their biological roles in health and disease, aiming at revealing novel therapeutic opportunities in reproductive and regenerative medicine [...]

The role of Akt signalling in the mammalian ovary

The serine/threonine protein kinase Akt is involved in many cellular processes including cell growth, survival, proliferation and metabolism. Akt activity is modulated downstream of phosphatidylinositol-3-kinase (PI3K) in response to different extracellular stimuli. In the mammalian ovary, Akt collaborates with other kinases in the regulation of coordinate follicle and oocyte development. Akt determines the pool of primordial follicles and the transition from quiescent to growing phase. In addition, the kinase modulates granulosa cell apoptosis throughout folliculogenesis. In oocytes Akt participates in the control of meiosis resumption and, at metaphase II stage, regulates polar body emission and spindle organization. Its inhibition negatively affects preimplantation embryo development. As a consequence of such a central role, Akt dysregulation is associated with several human diseases including infertility and ovarian cancer.[...

Between Community Spaces. Squares of Minor Centers of Calabria

The theme of open “community spaces” in recent years has to the development of important interdisciplinary issues. Nevertheless, the reading of smaller towns, in urbanistic, historical-anthropological and geographical terms appears less extended, considering the declination of public spaces as "squares." Starting from this declension we would like to introduce the first results of a research. The research had the aim of (re)interpreting the particular characteristics of these areas in specific areas such as small towns, using the region of Calabria for the case of analytic application. These communities have diverse and stratified living cultures, altered by settlement processes that have triggered two different types of urban contexts. The former often lead either to urban areas in depopulated decay or, in contrast, in places of memories: empty containers of relationships, sterile and crystallized museum objects, reduced to scenarios on which passing groups of visitors move necessarily from those realities. The latter often encircle primitive nuclei, asphyxiating them, or characterizing the so-called "dual" or "satellites" towns, completely detached from the original urban center in which all public functions are decentralized. The applied methodology is based on the reading of the historical-functional evolution of squares by the identification of codified compositional criteria. Through this research we seek to verify how urban planning, in synergy with other disciplines, can define processes of regeneration aimed at restoring the meaning of "center", and thus of an urban-community reference center

Effect of Estradiol and Progesterone on ovine Amniotic Epithelial Cells

This study was designed to clarify Estradiol (E2) and Progesterone (P4) steroid effects on ovine Amniotic Epithelial Cells (oAECs) that has a conserved plasticity and highly self-renewable capacity (Parolini et al., Stem Cells, 26(2), 300–311, 2008; Barboni et al., Stem Cell Rev Rep, 10:725–741, 2014). Based on their conserved immunomodulatory properties, oAECs are suitable for allo and xeno-transplantation (Barboni et al., Cell Transplant, 21(11), 2377–2395, 2012; Muttini et al., Res Vet Sci, 94(1),158–169, 2013). To date, no information is present on the effects of prolonged steroid exposition on AECs. oAECs were cultured as previously reported (Barboni et al., Cell Transplant. 21(11), 2377–2395, 2012) and treated with 12.5μM and 25μM of E2 or P4 (Sigma-Aldrich, Milan, Italy), alone and in both combinations, for three passages. Untreated cells were marked control (CTR). At 70% confluency, cells were detached for doubling time (DT) evaluation. Cells at fourth passage were differentiated for 21 days in osteogenic media (DM) (Mattioli et al., Cell Biol Int 36(1):7-19, 2012) without steroid. Alizarin Red and Alcian-Blue (Sigma-Aldrich, Milano, Italy) stainings were performed. RNA and cDNA were obtained as previously reported (Barboni et al., Cell Transplant. 21(11), 2377–2395, 2012). Real Time for NANOG, SOX2 ,OCT4 stemness genes expression were performed by SensiFast SYBR (Bioline, Aurogene, Rome, Italy) using specific primers (Mattioli et al., Cell Biol Int. 36(1):7-19, 2012).The protocol was: 5 min at 95°C, 30 cycles at 95°C for 15 sec, 60°C for 30 sec, 72°C for 15 sec. Comparative Ct 2-ΔΔC(t) normalization to GAPDH was applied. IHC analyses were carried out for Cytokeratin 8 and αSMA expression as previously reported (Barboni et al. PLoS ONE 7(2): e30974, 2012). Data expressed as mean (±SD), compared by one-way ANOVA followed by Tukey’s test (GraphPad Prism 5). Significant values for P < 0.05. Steroids treated ovine AECs proliferate with significant differences between concentrations. While P4 treated cells showed cuboidal shape and Cytokeratin expression until third passage, CTR and E2 treated cells showed a rapid downregulation of Cytokeratin and increased αSMA expression. oAECs with E2+P4 showed both cell type morphology. Steroids modified stemness genes based on the concentration. 12.5 μM E2, 25μM P4 and 25μM of both E2+P4 treatments maintained higher OCT4, NANOG and SOX2 expressions in treated cells despite their progressive downregulation in the CTR. Moreover, compared to CTR, after Alizarin staining, steroid pretreated cells suffered morphological changes under DM acquiring Alcian Blue-positive chondrogenic-like morphology. AECs stemness properties and plasticity can be modified by prolonged steroidal treatment. These data improve our knowledge, opening new prospective on oAEC use in stem cell-based therapy. Acknowledgments. Research supported by H2020-MSCA ITN EJD-REP BIOTECH 675526

p21(WAF1 )expression induced by MEK/ERK pathway activation or inhibition correlates with growth arrest, myogenic differentiation and onco-phenotype reversal in rhabdomyosarcoma cells

BACKGROUND: p21(WAF1), implicated in the cell cycle control of both normal and malignant cells, can be induced by p53-dependent and independent mechanisms. In some cells, MEKs/ERKs regulate p21(WAF1 )transcriptionally, while in others they also affect the post-transcriptional processes. In myogenic differentiation, p21(WAF1 )expression is also controlled by the myogenic transcription factor MyoD. We have previously demonstrated that the embryonal rhabdomyosarcoma cell line undergoes growth arrest and myogenic differentiation following treatments with TPA and the MEK inhibitor U0126, which respectively activate and inhibit the ERK pathway. In this paper we attempt to clarify the mechanism of ERK-mediated and ERK-independent growth arrest and myogenic differentiation of embryonal and alveolar rhabdomyosarcoma cell lines, particularly as regards the expression of the cell cycle inhibitor p21(WAF1). RESULTS: p21(WAF1 )expression and growth arrest are induced in both embryonal (RD) and alveolar (RH30) rhabdomyosarcoma cell lines following TPA or MEK/ERK inhibitor (U0126) treatments, whereas myogenic differentiation is induced in RD cells alone. Furthermore, the TPA-mediated post-transcriptional mechanism of p21(WAF1)-enhanced expression in RD cells is due to activation of the MEK/ERK pathway, as shown by transfections with constitutively active MEK1 or MEK2, which induces p21(WAF1 )expression, and with ERK1 and ERK2 siRNA, which prevents p21(WAF1 )expression. By contrast, U0126-mediated p21(WAF1 )expression is controlled transcriptionally by the p38 pathway. Similarly, myogenin and MyoD expression is induced both by U0126 and TPA and is prevented by p38 inhibition. Although MyoD and myogenin depletion by siRNA prevents U0126-mediated p21(WAF1) expression, the over-expression of these two transcription factors is insufficient to induce p21(WAF1). These data suggest that the transcriptional mechanism of p21(WAF1 )expression in RD cells is rescued when MEK/ERK inhibition relieves the functions of myogenic transcription factors. Notably, the forced expression of p21(WAF1 )in RD cells causes growth arrest and the reversion of anchorage-independent growth. CONCLUSION: Our data provide evidence of the key role played by the MEK/ERK pathway in the growth arrest of Rhabdomyosarcoma cells. The results of this study suggest that the targeting of MEK/ERKs to rescue p21(WAF1 )expression and myogenic transcription factor functions leads to the reversal of the Rhabdomyosarcoma phenotype

Effects of P4 Antagonist RU486 on VEGF and Its Receptors' Signaling during the In Vivo Transition from the Preovulatory to Periovulatory Phase of Ovarian Follicles

The development of an adequate blood vessel network is crucial for the accomplishment of ovarian follicle growth and ovulation, which is necessary to support the proliferative and endocrine functions of the follicular cells. Although the Vascular Endothelial Growth Factor (VEGF) through gonadotropins guides ovarian angiogenesis, the role exerted by the switch on of Progesterone (P4) during the periovulatory phase remains to be clarified. The present research aimed to investigate in vivo VEGF-mediated mechanisms by inducing the development of periovulatory follicles using a pharmacologically validated synchronization treatment carried out in presence or absence of P4 receptor antagonist RU486. Spatio-temporal expression profiles of VEGF, FLT1, and FLK1 receptors and the two major MAPK/ERKs and PI3K/AKT downstream pathways were analyzed on granulosa and on theca compartment. For the first time, the results demonstrated that in vivo administration of P4 antagonist RU486 inhibits follicular VEGF receptors' signaling mainly acting on the theca layer by downregulating the activation of ERKs and AKTs. Under the effect of RU486, periovulatory follicles' microarchitecture did not move towards the periovulatory stage. The present evidence provides new insights on P4 in vivo biological effects in driving vascular and tissue remodeling during the periovulatory phase

Biomimetic PLGA 3D Scaffold Potentiate Amniotic Epithelial Stem Cells Biological Capability for Tendon Tissue Engineering Applications

INTRODUCTION: Tendon tissue engineering represents a promising solution to deal with tendinopathies and aims to develop effective implantable 3D biomimetic scaffolds with ideally native tissue’s physical, mechanical, biological, and functional qualities. These constructs can be engineered with stem cells to potentiate their teno-inductive and immunomodulatory properties (El Khatib, Mauro, Di Mattia, et al., 2020; El Khatib, Mauro, Wyrwa, et al., 2020; Russo et al., 2020). In this context, amniotic epithelial stem cells (AECs) have recently received much attention in the field of regenerative medicine due to their capacity to differentiate into the tenogenic lineage and to their immunomodulatory profile (Barboni et al., 2012, 2018; Mauro et al., 2016). The focus of this research was to create bundle tendon-like PLGA 3D scaffolds, which mimic tendon macro and micro-architecture and biomechanics, and to assess their impacts on AECs’ biological potential. METHODS: PLGA fleeces, with highly aligned fibers, were fabricated via electrospinning technique through a rotatory collector. The obtained fleeces were then wrapped manually to form 3D tendon-like scaffolds, which were evaluated in terms of structure, mechanical characteristics, and biological influence on AECs by conducting in vitro experiments. Indeed, ovine AECs, seeded on the PLGA 3D scaffolds and fleeces, were compared for their morphological changes and for the cytoplasmic expression of TNMD, a mature tendon protein, respect to cells cultured on Petri dishes (CTR), after 48h and 7d of culture through a confocal microscope. Moreover, the teno-differentiative potential and immunomodulatory properties of the produced constructs were assessed by analyzing the gene expression of tendon related markers (early: SCX, late: COL1 and TNMD) and of anti- (IL10) and pro- (IL12) inflammatory cytokines respectively. Moreover, the present research evaluated YAP protein activation in the engineered AECs through immunofluorescence assay by assessing its cellular localization. RESULTS: The produced PLGA 3D scaffolds, analyzed though a scanning electron microscope, showed high fiber alignment, which closely resemble the architecture, both macroscopically and microscopically, and the biomechanical properties of native tendon tissue. AECs seeded on the produced constructs exhibited an elongated tenocyte-like morphology already after 24 hours, while AECs cultivated on petri dishes (CTR) retained their characteristic polygonal morphology. The engineered AECs' phenotypic change was also confirmed by visualizing the cytoplasmic expression of TNMD protein and supported by tendon-related genes (SCX, COL1, and TNMD) upregulation at 7-day culture respect to CTR cells (p<0.05), which showed no TNMD protein expression or significant increase in tendon-related genes. Moreover, AECs seeded on 3D PLGA scaffolds showed an anti-inflammatory profile, with a significant higher IL10/IL12 ratio respect to the CTR (p<0.05). Finally, 3D scaffolds with highly aligned fibers stimulated AECs in terms of cell cytoskeleton stress, activating their mechanosensitive YAP pathway by significantly increasing YAP nuclear localization compared to the CTR (p<0.05), in which YAP was instead localized in the cytoplasm. DISCUSSION & CONCLUSIONS: Overall, these results support the biomimicry of the fabricated scaffolds in terms of structure and biomechanics and reveal their great teno/immuno-inductive potential and mechanosensing stimulus on AECs, thus standing biomimetic PLGA 3D scaffolds as a potential candidate for tendon regeneration