Combined Exogenous Activation of Bovine Oocytes: Effects on Maturation-Promoting Factor, Mitogen-Activated Protein Kinases, and Embryonic Competence.

Oocyte activation via dual inhibition of protein synthesis and phosphorylation has improved in vitro embryo production in different mammalian species. In this study, we evaluated the effects of the combination of cycloheximide (CHX), dimethyl amino purine (DMAP), and anisomycin (ANY) on the activation of bovine oocytes, particularly on dynamics of MPF and MAPKs, embryonic developmental potential, and quality. The results showed that the cleavage and blastocyst rates, as well as levels of CCNB1, CDK1, p-CDK1Thr161, and p-CDK1Thr14-Tyr15, were similar among groups; ANY and ANY + CHX reduced the expression of ERK1/2 compared to DMAP-combinations (p < 0.05), whereas ANY + DMAP, CHX + DMAP, and ANY + CHX + DMAP reduced p-ERK1/2 compared to ANY and ANY + CHX treatments (p < 0.05). The quality of blastocysts in terms of cell counts, their allocation, and the numbers of TUNEL-positive cells did not differ among groups. However, transcript levels of POU5F1 were higher in embryos derived from ANY + CHX + DMAP treatment compared to other groups, while expression levels of CDX2 did not show differences. In addition, the BCL2A1/BAX ratio of the ANY + CHX + DMAP treatment was significantly low compared to the ANY treatment (p < 0.05) and did not differ significantly from the other treatments. In conclusion, oocyte activation by dual inhibition of protein synthesis and phosphorylation induces MPF inactivation without degradation of CCNB1, while MAPK inactivation occurs differentially between these inhibitors. Thus, although the combined use of these inhibitors does not affect early developmental competence in vitro, it positively impacts the expression of transcripts associated with embryonic quality.

Activation of bovine oocytes by protein synthesis inhibitors: new findings on the role of MPF/MAPKs†.

The present study evaluated the mechanism by which protein synthesis inhibitors activate bovine oocytes. The aim was to analyze the dynamics of MPF and MAPKs. MII oocytes were activated with ionomycin (Io), ionomycin+anisomycin (ANY) and ionomycin+cycloheximide (CHX) and by in vitro fertilization (IVF). The expression of cyclin B1, p-CDK1, p-ERK1/2, p-JNK, and p-P38 were evaluated by immunodetection and the kinase activity of ERK1/2 was measured by enzyme assay. Evaluations at 1, 4, and 15 hours postactivation (hpa) showed that the expression of cyclin B1 was not modified by the treatments. ANY inactivated MPF by p-CDK1Thr14-Tyr15 at 4 hpa (P < 0.05), CHX increased pre-MPF (p-CDK1Thr161 and p-CDK1Thr14-Tyr15) at 1 hpa and IVF increased p-CDK1Thr14-Tyr15 at 17 hours postfertilization (hpf) (P < 0.05). ANY and CHX reduced the levels of p-ERK1/2 at 4 hpa (P < 0.05) and its activity at 4 and 1 hpa, respectively (P < 0.05). Meanwhile, IVF increased p-ERK1/2 at 6 hpf (P < 0.05); however, its kinase activity decreased at 6 hpf (P < 0.05). p-JNK in ANY, CHX, and IVF oocytes decreased at 4 hpa (P < 0.05). p-P38 was only observed at 1 hpa, with no differences between treatments. In conclusion, activation of bovine oocytes by ANY, CHX, and IVF inactivates MPF by CDK1-dependent specific phosphorylation without cyclin B1 degradation. ANY or CHX promoted this inactivation, which seemed to be more delayed in the physiological activation (IVF). Both inhibitors modulated MPF activity via an ERK1/2-independent pathway, whereas IVF activated the bovine oocytes via an ERK1/2-dependent pathway. Finally, ANY does not activate the JNK and P38 kinase pathways.

Human endometrial stromal cells inhibit the pro-angiogenic stimulus of hCG in vitro.

During embryo implantation, endometrial angiogenesis is regulated by signals originating from the endometrium itself and the developing embryo. It has been suggested that hCG may play a pro-angiogenic role; therefore, we sought to understand its regulatory role in blood vessel formation in human endometrium using in vivo and in vitro models. In the in vivo model, we screened 16 angiogenesis-related transcripts in the endometrium upon intrauterine administration of hCG. Oocyte donors were recruited and during their controlled ovarian stimulation cycle received a single dose of hCG or vehicle on the day of oocyte pick up during a cycle of ovarian stimulation. One hour before obtaining an endometrial sample, women received an intrauterine administration of vehicle or hCG (500, 1500 and 5000 IU). Transcript and protein analysis showed that MMP3 and VEGFA increased, whereas TIMP1 decreased. The in vitro analysis studied the angiogenic potential of conditioned medium (CM) from primary cultures of human endometrial stromal cells (ESC) stimulated with hCG. Using a 2D and 3D in vitro angiogenesis assays, our results indicate that CM from ESC almost completely inhibits the capillary-like structure formation in endothelial cells, overriding the pro-angiogenic effect of hCG; and this inhibition due to secreted factors present in CM specifically reduced the migration potential of endothelial cells. In conclusion, the endometrial stromal milieu seems to modulate the direct pro-angiogenic effects of hCG on endothelial cells during embryo implantation.

Efectividad de la distracción tibiofemoral en la funcionalidad adicionada al tratamiento convencional en pacientes mayores de 50 años con osteoartritis de rodilla: un estudio piloto / Effectiveness of tibiofemoral distraction in the functionality added to conventional treatment in patients over 50 years with knee osteoarthritis: a pilot study

RESUMEN: Osteoartritis (OA) es una de las enfermedades reumáticas más frecuentes y la más común enfermedad articular, afecta principalmente al cartílago articular y el hueso subcondral de una articulación sinovial resultando en la incapacidad articular. La OA es reconocida como una causa substancial de discapacidad, con significativos costos sociales y financieros debidos a las frecuentes intervenciones médicas y quirúrgicas además del ausentismo laboral. El objetivo del estudio fue determinar si la distracción tibiofemoral adicionada al tratamiento convencional en pacientes con osteoartritis de rodilla grado 3, presenta mejoras en el dolor, rango de movimiento y funcionalidad de la extremidad inferior, en comparación al tratamiento convencional propuesto por el MINSAL por sí solo. Esta investigación corresponde a un estudio piloto, con diseño experimental del tipo ensayo clínico aleatorizado (ECA), controlado, ciego simple y con una muestra equilibrada. La muestra corresponde a pacientes reclutados del Hospital San Borja Arriarán (Santiago, Chile) con diagnóstico médico de OA de rodilla grado 3. Se realizaron dos mediciones, una al inicio de las diez sesiones y otra al final del tratamiento, donde se midió el dolor con la escala visual análoga (EVA), el rango de movimiento articular pasivo con goniometría y la capacidad funcional con el test de marcha de 6 minutos y el cuestionario de WOMAC. Al comparar ambos grupos muestran diferencias estadísticamente significativas en la funcionalidad, el dolor y distancia de marcha durante 6 minutos. La distracción tibiofemoral adicionada al tratamiento convencional presentó mejoras clínicas significativas cuando comparada con la aplicación del tratamiento convencional de OA de rodilla.

SUMMARY: Osteoarthritis (OA) is one of the most frequent rheumatic diseases and the most common joint disease, primarily affecting joint cartilage and the subchondral bone of a synovial joint resulting in the y articular dysfunction. OA is recognized as a cause of disability, with significant social and financial costs due to medical, surgical interventions in addition to frequent absenteeism at work. The objective was to determine if tibiofemoral distraction, in conjunction with conventional therapy in patients with knee osteoarthritis grade 3, improved performance of the lower extremity in comparison to the conventional treatment alone, as proposed by the Ministry of Health (MINSAL). This research is a pilot, prospective randomized clinical trial (RCT), controlled, single-blind and with a balanced sample. The sample was recruited from patients of the Hospital San Borja Arriarán (Santiago, Chile) with medical diagnosis of knee OA grade 3. Two measurements were performed, one at the beginning of the 10 sessions and at the end of treatment, which was measured with the functionality questionnaire of OA of the Western Ontario and McMaster Universities (WOMAC), the pain visual analog scale (VAS), the passive joint range of motion with goniometry, and distance to the Test 6-minute walk. When comparing the two groups showed statistically significant differences in functionality, pain, distance walked and joint range, except in knee grade extension. The tibiofemoral distraction added to conventional treatment functional improvement in patients with knee OA grade 3.

hCG activates Epac-Erk1/2 signaling regulating Progesterone Receptor expression and function in human endometrial stromal cells.

STUDY QUESTION: How does hCG signal in human endometrial stromal cells (ESCs) and what is its role in regulating ESC function? SUMMARY ANSWER: hCG signaling in ESCs activates the extracellular signal-regulated protein kinases 1 and 2 (Erk1/2) pathway through exchange protein activated by cyclic AMP (cAMP) (Epac) and transiently increases progesterone receptor (PR) transcript and protein expression and its transcriptional function. WHAT IS KNOWN ALREADY: hCG is one of the earliest embryo-derived secreted signals in the endometrium, which abundantly expresses LH/hCG receptors. hCG signals through cAMP/protein kinase A (PKA) in gonadal cells, but in endometrial epithelial cells, hCG induces Erk1/2 activation independent of the cAMP/PKA pathway. Few data exist concerning the signal transduction pathways triggered by hCG in ESCs and their role in regulation of ESC function. STUDY DESIGN, SIZE, DURATION: This is an in vitro study comprising patients undergoing benign gynecological surgery (n = 46). PARTICIPANTS/MATERIALS, SETTING, METHODS: Endometrial samples were collected from normal cycling women during the mid-secretory phase for ESCs isolation. The study conducted in an academic research laboratory within a tertiary-care hospital. The activation of the Erk1/2 signal transduction pathway elicited by hCG was evaluated in ESC. Signaling pathway inhibitors were used to examine the roles of PKA, PI3K, PKC, adenylyl cyclase and Epac on the hCG-stimulated up-regulation of phospho-Erk1/2 (pErk1/2). Erk1/2 phosphorylation was determined by immunoblot. siRNA targeting Epac was used to investigate the molecular mechanisms. To assess the role of Erk1/2 signaling induced by hCG on ESC function, gene expression regulation was examined by immunofluorescence and real-time quantitative PCR. The role of PR on the regulation of transcript levels was studied using progesterone and the PR antagonist RU486. All experiments were conducted using at least three different cell culture preparations in triplicate. MAIN RESULTS AND THE ROLE OF CHANCE: Addition of hCG to ESCs in vitro induced the phosphorylation of Erk1/2 through cAMP accumulation. Such induction could not be blocked by inhibitors for PKA, PKC and PI3K. Epac inhibition and knockdown with siRNA prevented pErk1/2 induction by hCG. ESCs stimulated with hCG for up to 72 h showed a significant increase in PR mRNA and immunofluorescent label at 48 h only; an effect that was abrogated with the mitogen-activated protein kinase kinase inhibitor UO126. In addition, the hCG-activated Erk1/2 pathway significantly decreased the mRNA levels for secreted frizzled-related protein 4 (SFRP4) at 24 h, whereas it increased those for homeobox A10 (HOXA10) at 48 h (P = 0.041 and P = 0.022 versus control, respectively). Prolactin mRNA levels were not significantly modified. HOXA10 mRNA up-regulation by hCG was not enhanced by co-stimulation with progesterone; however, it was completely abolished in the presence of RU486 (P = 0.036 hCG versus hCG + RU486). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: This is an in vitro study utilizing stromal cell cultures from human endometrial tissues. Furthermore, results obtained should also be confirmed in vivo in the context of the whole human endometrial tissue and hormonal milieu. The in vitro experiments using hCG have been conducted without other hormones/factors that may also modulate the ESCs response to hCG. WIDER IMPLICATIONS OF THE FINDINGS: We have determined that hCG induces the PR through the Erk1/2 pathway in ESCs which may render them more sensitive to progesterone, increasing our understanding about the effects of hCG at the embryo-maternal interface. The activation of such a pathway in the context of the hormonal milieu during the window of implantation might contribute to a successful dialog between the embryo and the uterus, leading to appropriate endometrial function. Defective hCG signaling in the endometrial stromal tissue may lead to an incomplete uterine response, compromising embryo implantation and early pregnancy. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Fund for Scientific and Technological Development, Government of Chile (FONDECYT) grants 11100443 and 1140614 (A.T.-P.). The authors have no conflicts of interest to declare.

Experimental-Theoretical Approach to the Adsorption Mechanisms for Anionic, Cationic, and Zwitterionic Surfactants at the Calcite-Water Interface.

The adsorption of surfactants (DTAB, SDS, and CAPB) at the calcite-water interface was studied through surface zeta potential measurements and multiscale molecular dynamics. The ground-state polarization of surfactants proved to be a key factor for the observed behavior; correlation was found between adsorption and the hard or soft charge distribution of the amphiphile. SDS exhibits a steep aggregation profile, reaching saturation and showing classic ionic-surfactant behavior. In contrast, DTAB and CAPB featured diversified adsorption profiles, suggesting interplay between supramolecular aggregation and desorption from the solid surface and alleviating charge buildup at the carbonate surface when bulk concentration approaches CMC. This manifests as an adsorption profile with a fast initial step, followed by a metastable plateau and finalizing with a sharp decrease and stabilization of surface charge. Suggesting this competition of equilibria, elicited at the CaCO3 surface, this study provides atomistic insight into the adsorption mechanism for ionic surfactants on calcite, which is in accordance with experimental evidence and which is a relevant criterion for developing enhanced oil recovery processes.

Role of 2-methoxyestradiol, an Endogenous Estrogen Metabolite, in Health and Disease.

Estradiol (E2) is a steroid hormone whose physiological actions are mainly mediated by its interaction with intracellular estrogen receptors (ER) leading to modification on the mRNA and protein synthesis in its target cells. However, estrogens can also activate several intracellular signal transduction cascades by non-genomic mechanisms. Estrogens must be inactivated and removed from blood through its conversion to soluble compounds with an apparent low estrogenic activity and decreased affinity for ER. In this context, 2-methoxyestradiol (2ME2) is generated by a sequential hydroxylation of E2 via the enzyme cytochrome P450 isoform 1A1 to produce 2-hydroxyestradiol (2OHE2) followed by a conjugation reaction catalyzed by the enzyme Catechol-O-Methyltransferase generating 2ME2 from 2OHE2. Recent evidence indicates that physiological concentration of 2ME2 may regulate several biological processes while high concentrations of this metabolite may induce pathophysiological alterations in several tissues. In the last years, 2ME2 has also been described as a promising anticancer drug although its cellular and molecular mechanisms are still being disclosed. Herein, we will review the available literature concerning the role of 2ME2 in health and disease. We will focus on to describing the intracellular mechanisms by which 2ME2 exerts its effects on reproductive and non-reproductive tissues. The promising anticancer effects of 2ME2 and its synthetic derivatives will also be discussed. Finally, a group of 2ME2-target genes that could be used as biomarkers of 2ME2 under physiological or pathophysiological conditions will be reviewed.