EIF5A1 promotes trophoblast migration and invasion via ARAF-mediated activation of the integrin/ERK signaling pathway.

Trophoblast dysfunction is one mechanism implicated in the etiology of recurrent miscarriage (RM). Regulation of trophoblast function, however, is complex and the mechanisms contributing to dysregulation remain to be elucidated. Herein, we found EIF5A1 expression levels to be significantly decreased in cytotrophoblasts in RM villous tissues compared with healthy controls. Using the HTR-8/SVneo cell line as a model system, we found that overexpression of EIF5A1 promotes trophoblast proliferation, migration and invasion in vitro. Knockdown of EIF5A1 or inhibiting its hypusination with N1-guanyl-1,7-diaminoheptane (GC7) suppresses these activities. Similarly, mutating EIF5A1 to EIF5A1K50A to prevent hypusination abolishes its effects on proliferation, migration and invasion. Furthermore, upregulation of EIF5A1 increases the outgrowth of trophoblasts in a villous explant culture model, whereas knockdown has the opposite effect. Suppression of EIF5A1 hypusination also inhibits the outgrowth of trophoblasts in explants. Mechanistically, ARAF mediates the regulation of trophoblast migration and invasion by EIF5A1. Hypusinated EIF5A1 regulates the integrin/ERK signaling pathway via controlling the translation of ARAF. ARAF level is also downregulated in trophoblasts of RM villous tissues and expression of ARAF is positively correlated with EIF5A1. Together, our results suggest that EIF5A1 may be a regulator of trophoblast function at the maternal-fetal interface and low levels of EIF5A1 and ARAF may be associated with RM.

Stretchable Electrochemical Sensor for Real-Time Monitoring of Cells and Tissues.

Stretchable electrochemical sensors are conceivably a powerful technique that provides important chemical information to unravel elastic and curvilinear living body. However, no breakthrough was made in stretchable electrochemical device for biological detection. Herein, we synthesized Au nanotubes (NTs) with large aspect ratio to construct an effective stretchable electrochemical sensor. Interlacing network of Au NTs endows the sensor with desirable stability against mechanical deformation, and Au nanostructure provides excellent electrochemical performance and biocompatibility. This allows for the first time, real-time electrochemical monitoring of mechanically sensitive cells on the sensor both in their stretching-free and stretching states as well as sensing of the inner lining of blood vessels. The results demonstrate the great potential of this sensor in electrochemical detection of living body, opening a new window for stretchable electrochemical sensor in biological exploration.

[Tetramethoxystilbene, a selective CYP1B1 inhibitor, suppresses adipogenesis of C3H10T1/2 pluripotent stem cells].

OBJECTIVE: To investigate the inhibitory effects of tetramethoxystilbene, a selective CYP1B1 inhibitor, on adipogenic differentiation of C3H10T1/2 multi-potent mesenchymal cells. METHODS: In vitro cultured C3H10T1/2 cells at full confluence were induced by adipogenic agents (10 µg/ml insulin, 2 µmol/L dexamethasone and 0.5 mmol/L 3-isobutyl-1-methylxanthine) and exposed simultaneously to TMS at the final concentrations of 1.0, 2.0 or 4.0 µg/ml. Oil Red-O staining was used to observe the cell differentiation. The expression of peroxisome proliferator-activated receptor gamma (PPARγ) and its target genes cluster of differentiation 36 (CD36) and fatty acid binding protein 4 (FABP4) were quantified by real-time RT-PCR and Western blotting. RESULTS: Oil Red-O staining and TG contents revealed that TMS suppressed induced differentiation of C3H10T1/2 cells. TMS exposure of the cells dose-dependently decreased both mRNA and protein expressions of PPARγ, a key nuclear transcription factor during adipogenesis, and also lowered the mRNA expressions of PPARγ target genes CD36 and FABP4. CONCLUSION: TMS can suppress adipogenic differentiation of C3H10T1/2 cells by inhibiting PPARγ