Preeclampsia (PE) is a serious pregnancy complication closely linked to trophoblast dysfunction. Recent studies highlight the importance of N⁶-methyladenosine (m⁶A) modification in placental development; however, its role in PE-associated trophoblast dysfunction remains poorly understood. This study aimed to elucidate the regulatory role of METTL3 in trophoblast cell function under hypoxia, a key pathological feature associated with preeclampsia, with a focus on its downstream target SLC2A1. A hypoxic model was established using HTR-8/SVneo trophoblast cells. METTL3 expression was evaluated using RT-qPCR and western blotting. METTL3 expression was modulated through siRNA-mediated knockdown and plasmid-based overexpression. Cell proliferation, apoptosis, migration, and invasion were evaluated using EdU, flow cytometry, and Transwell assays. With SLC2A1 as our pre-selected candidate, ENCORI and SRAMP databases were used to investigate METTL3 as a potential upstream m⁶A regulator of SLC2A1. The regulatory impact of METTL3 on SLC2A1 m⁶A methylation and mRNA stability was assessed through MeRIP-qPCR and actinomycin D assays. To confirm the functional relationship between METTL3 and SLC2A1, combined knockdown of METTL3 and SLC2A1 was performed. Hypoxic stimulation significantly upregulated METTL3 expression in HTR-8/SVneo cells. METTL3 silencing markedly enhanced trophoblast cell proliferation, migration, and invasion, while reducing apoptosis, whereas METTL3 overexpression produced the opposite effects. Mechanistically, METTL3 promoted m6A modification of SLC2A1 mRNA and accelerated its degradation, thereby suppressing SLC2A1 expression. Moreover, co-silencing SLC2A1 significantly attenuated the pro-proliferative and pro-migratory effects induced by METTL3 knockdown, suggesting that SLC2A1 functions as a critical downstream effector in METTL3-mediated regulation of trophoblast cell function. METTL3 is aberrantly upregulated under hypoxic conditions and suppresses the mRNA stability and expression of SLC2A1 through m⁶A modification, thereby inhibiting the proliferative and invasive capacities of trophoblast cells.
Cerium oxide nanoparticles (CeO₂ NPs) have attracted considerable interest because of their redox-related antioxidant properties, while surface modification with chitosan may alter their physicochemical and biological behavior. However, the balance between antioxidant activity and hemocompatibility following chitosan association remains insufficiently characterized. In this study, CeO₂ NPs were synthesized using a chemical precipitation method and subsequently associated with chitosan. The physicochemical characteristics of the synthesized CeO₂ NPs were evaluated using transmission electron microscopy (TEM), atomic force microscopy (AFM), UV–visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and zeta-potential analysis. The antioxidant activity of bare CeO₂ and chitosan-associated CeO₂ (CS-CeO₂) NPs was comparatively evaluated at concentrations of 62.5–1000 µg/mL using free-radical scavenging assays. Hemolytic activity was assessed using human erythrocytes over the same concentration range. The synthesized CeO₂ NPs exhibited heterogeneous particle-size distributions, with TEM-observed particle sizes ranging from approximately 52 to 450 nm and an AFM-derived mean diameter of 64.71 nm. The CeO₂ NPs showed a positive zeta potential of + 13.5 mV. CS-CeO₂ NPs generally exhibited higher antioxidant activity than bare CeO₂ NPs, although statistically significant differences were observed only at selected concentrations. The antioxidant activity of CS-CeO₂ NPs ranged from 6.1 ± 1.2
Cytarabine (Ara-C) is a core drug for the treatment of acute myeloid leukemia (AML), but its efficacy is often limited by drug resistance. Luteolin has been shown to inhibit AML cell proliferation and induce apoptosis; however, whether the combined application of both agents can further inhibit AML cell proliferation remains unclear. Ara-C-resistant cell models were established using HL-60/KG-1 cells, and Ara-C-resistant HL-60 cells were injected into nude mice to establish a xenograft animal model. Cell proliferation and apoptosis were detected using a CCK-8 assay, soft agar colony formation assay, and flow cytometry. Western blotting was used to detect protein expression. Luteolin significantly inhibited the proliferation of Ara-C-resistant AML cells. Compared with single-drug treatment, combined treatment with luteolin and Ara-C further reduced cell viability and colony formation ability and induced S-phase cell cycle arrest and apoptosis. Additionally, luteolin alone or in combination with Ara-C significantly inhibited the growth of drug-resistant AML xenograft tumors. Mechanistic studies revealed that luteolin significantly suppressed the expression of Nrf2 and its downstream antioxidant proteins HO-1 and NQO1, reduced intracellular GSH levels, and promoted ROS accumulation. The Nrf2 activator ML334 partially reversed the therapeutic effect of luteolin. Further investigation revealed that luteolin did not affect Keap1 expression but inhibited GSK3β phosphorylation, thereby activating GSK3β. The GSK3β inhibitor LiCl attenuated the ability of luteolin to promote Nrf2 ubiquitination and degradation. Luteolin inhibits the proliferation of Ara-C-resistant AML cells by activating GSK3β to promote Nrf2 ubiquitination and degradation, thereby inhibiting Nrf2-mediated antioxidant effects. The combined treatment of luteolin and Ara-C is more effective than either agent alone.
To reduce the operational complexity of conventional dual-feed fed-batch processes while maintaining high productivity, an intensified cell culture strategy integrating a commercial single-feed medium with N-1 perfusion-based high-density inoculation was developed using a CHO-K1 cell line expressing a bispecific antibody. Six commercially available single-feed media were first evaluated in shake-flask cultures, and the selected medium achieved cell growth, metabolic performance, antibody titer, and product quality comparable to those of a conventional dual-feed process. To further improve productivity, N-1 perfusion intensification enabled inoculation at 10 × 106 cells/mL in 2 L bioreactors. High-density cultures entered the stationary phase earlier while maintaining elevated viable cell densities throughout production. When combined with the single-feed strategy, The IFB-Single process achieved a final antibody titer of 9.4 g/L, approximately 24
Endothelial dysfunction is an initiating event of atherosclerosis (AS). Circular RNAs (circRNAs) have been implicated in endothelial injury. This study aimed to investigate the function and mechanism of circCRIM1 (hsa_circ_0007386) in AS-related endothelial injury. GSE152280 and GSE115733 datasets were acquired to identify differentially expressed circRNAs in AS. circCRIM1 expression was validated in serum from 30 AS patients and 30 healthy controls. An in vitro AS model was established by exposing human coronary artery endothelial cells (HCAECs) to 50 µg/mL oxidized low-density lipoprotein (ox-LDL) for 24 h. The subcellular localization of circCRIM1 were measured by Fluorescence in situ hybridization. Cell injury was evaluated by detecting cell viability, proliferation, LDH release, inflammation, and ferroptosis after circCRIM1 overexpression or knockdown. The underlying mechanism was explored through bioinformatics analysis, dual-luciferase reporter assay, RT-qPCR, Western blot, and rescue experiments. circCRIM1 expression was decreased, whereas miR-567 was increased, in AS and ox-LDL-treated HCAECs. circCRIM1 was mainly localized to the cytoplasm. circCRIM1 overexpression conferred protective effects against ox-LDL-induced injury in HCAECs, as manifested by enhanced cell viability and EdU-positive cell number, attenuated LDH release, reduced secretion of inflammatory cytokines (TNF-α and IL-6), and mitigation of ferroptosis characterized by decreased Fe2+, MDA, and lipid ROS levels, increased SOD activity, downregulated ACSL4, and upregulated GPX4. Conversely, circCRIM1 knockdown aggravated ox-LDL-induced cellular damage. miR-567 mimic exacerbated, whereas miR-567 inhibitor alleviated ox-LDL-induced injury of HCAECs. PRDX3 was identified as a direct target of miR-567, and circCRIM1 served as a miR-567 sponge to regulate PRDX3. Both miR-567 mimic and PRDX3 siRNA partially abrogated the protective effects of circCRIM1 upregulation. circCRIM1 relieves ox-LDL-induced endothelial inflammation and ferroptosis by regulating the miR-567/PRDX3 axis in AS.
