Effects of IL-11/IL-11 Receptor Alpha on Proliferation and Steroidogenesis in Ovarian Granulosa Cells of Dairy Cows.

Granulosa cells (GCs) are essential for follicular growth, oocyte maturation, and steroidogenesis in the ovaries. Interleukin (IL)-11 is known to play a crucial role in the decidualization of the uterus, however, the expression of the IL-11 system (IL-11, IL-11Rα, and gp130) in the bovine ovary and its exact role in GCs have not been extensively studied. In this study, we identified the IL-11 signaling receptor complex in the bovine ovary and investigated the regulatory effects and underlying mechanism of IL-11Rα on the proliferation and steroidogenesis of GCs. We observed that the IL-11 complex was highly expressed in the GCs of large follicles. IL-11Rα knockdown significantly inhibited GC proliferation by inducing cell cycle arrest at the G1 phase, along with a significant downregulation of proliferating cell nuclear antigen (PCNA) and Cyclin D1 (CCND1) protein, and induced GC apoptosis by significantly upregulating the ratio of BCL-2-associated X protein (BAX) and B-cell lymphoma-2 (BCL-2). In addition, IL-11Rα knockdown attenuated the Janus kinase (JAK) 1-signal transducer and activator of transcription 3 (STAT3) signaling, which is related to cell proliferation and apoptosis. Furthermore, the enzyme-linked immunosorbent assay (ELISA) indicated that IL-11Rα silencing decreased the basal and forskolin (FSK)-stimulated secretions of estradiol and progesterone in GC culture medium concomitantly with a remarkable decrease in cytochrome P450 family 19 subfamily A member 1 (CYP19A1) and steroidogenic acute regulatory protein (StAR). We subsequently determined that this reduction in steroidogenesis was in parallel with the decrease in phosphorylations of protein kinase A (PKA) substrates, cAMP-response element binding protein (CREB), extracellular regulated protein kinase (ERK) 1/2, and p38 mitogen-activated protein kinase (MAPK). Taken together, these data indicate that the effects of IL-11/IL-11Rα on the proliferation and steroidogenesis in bovine GCs is mediated by the JAK1-STAT3, PKA-CREB, p38MAPK, and ERK1/2 signaling pathways. Our findings provide important insights into the local action of the IL-11 system in regulating ovarian function.

PGC7 Regulates Genome-Wide DNA Methylation by Regulating ERK-Mediated Subcellular Localization of DNMT1.

DNA methylation is an epigenetic modification that plays a vital role in a variety of biological processes, including the regulation of gene expression, cell differentiation, early embryonic development, genomic imprinting, and X chromosome inactivation. PGC7 is a maternal factor that maintains DNA methylation during early embryonic development. One mechanism of action has been identified by analyzing the interactions between PGC7 and UHRF1, H3K9 me2, or TET2/TET3, which reveals how PGC7 regulates DNA methylation in oocytes or fertilized embryos. However, the mechanism by which PGC7 regulates the post-translational modification of methylation-related enzymes remains to be elucidated. This study focused on F9 cells (embryonic cancer cells), which display high levels of PGC7 expression. We found that both knockdown of Pgc7 and inhibition of ERK activity resulted in increased genome-wide DNA methylation levels. Mechanistic experiments confirmed that inhibition of ERK activity led to the accumulation of DNMT1 in the nucleus, ERK phosphorylated DNMT1 at ser717, and DNMT1 Ser717-Ala mutation promoted the nuclear localization of DNMT1. Moreover, knockdown of Pgc7 also caused downregulation of ERK phosphorylation and promoted the accumulation of DNMT1 in the nucleus. In conclusion, we reveal a new mechanism by which PGC7 regulates genome-wide DNA methylation via phosphorylation of DNMT1 at ser717 by ERK. These findings may provide new insights into treatments for DNA methylation-related diseases.

Preparation and Application of Nanocomposite Thin-Film Temperature Sensor during the Milling Process.

During the titanium alloy milling process, high temperatures in the tool-chip contact area will affect the tool life and precision of titanium alloy machining. Therefore, it is essential to measure the temperature of the tool-chip contact area continuously. In this paper, a finite element simulation model of the milling process was established using ABAQUS2020 to obtain the highest temperature location in the tool-chip contact area when milling titanium alloy. The integration of the wire with the alumina ceramic substrate formed an integrated wire substrate. Furthermore, NiCr, NiSi, and SiO2 films were deposited on the substrate sequentially using the DC pulsed magnetron sputtering technique. Finally, its microscopic morphology and static and dynamic performance were tested. The results show that the developed thin-film thermocouple temperature sensor has a Seebeck coefficient of 40.72 µV/°C and a dynamic response time of 0.703 ms. The application of the sensor to our titanium alloy milling experiments showed that the sensor can monitor the transient temperature in the tool-chip contact area, and its temperature measurement performance showed no detrimental effect from wearing. The effect of each milling parameter on the milling temperature was analyzed using ANOVA, and a regression model with an R-sq of 96.76% was obtained for the milling temperature.