Shanxi Medical University First Hospital

Although N⁶-methyladenosine (m⁶A) may be related to the pathogenesis of fibrotic process, the mechanism of m⁶A modification in aging-related idiopathic pulmonary fibrosis (IPF) remains unclear. Three-milliliter venous blood was collected from IPF patients and healthy controls. MeRIP-seq and RNA-seq were utilized to investigate differential m⁶A modification. The expressions of identified m⁶A regulator and target gene were validated using MeRIP-qPCR and real-time PCR. Moreover, we established an animal model and a senescent model of A549 cells to explore the associated molecular mechanism. Our study provided a panorama of m⁶A methylation in IPF. Increased peaks (3756) and decreased peaks (4712) were observed in the IPF group. The association analysis showed that 749 DEGs were affected by m⁶A methylation in IPF. Among the m⁶A regulators, the expression of METTL14 decreased in IPF. The m⁶A level of our interested gene DDIT4 decreased significantly, but the mRNA level of DDIT4 was higher in IPF. This was further verified in bleomycin-induced pulmonary fibrosis. At the cellular level, it was further confirmed that METTL14 and DDIT4 might participate in the senescence of alveolar epithelial cells. The downregulation of METTL14 might inhibit the decay of DDIT4 mRNA by reducing the m⁶A modification level of DDIT4 mRNA, leading to high expression of DDIT4 mRNA and protein. Our study provided a panorama of m⁶A alterations in IPF and discovered METTL14 as a potential intervention target for epigenetic modification in IPF. These results pave the way for future investigations regarding m⁶A modifications in aging-related IPF.

Intrauterine adhesion (IUA) presents a significant challenge in gynecology, characterized by excessive fibrosis and compromised reproductive function, leading to severe infertility. Although biocompatible hydrogels integrated with stem cells offer a promising approach for IUA therapy, clinical applications remain limited. Recent studies have highlighted the role of ferroptosis and reactive oxygen species (ROS) in IUA pathogenesis, yet strategies targeting ferroptosis through antioxidant stress are underexplored. This study investigates the therapeutic effects and mechanisms of a Ru-Single-Atom Nanozyme (Ru-SAN) incorporated into chitosan hydrogel for treating IUA. Ru-SAN, which mimics the enzyme activities of catalase, superoxide dismutase, and glutathione peroxidase, effectively clears excess ROS and shows promise in treating oxidative stress-induced diseases. The results demonstrate the superior antioxidative capabilities of Ru-SAN, significantly suppressing the ROS-ferroptosis cycle at the injury site. This creates a favorable microenvironment for post-injury repair by inhibiting inflammation, enhancing mesenchymal-to-epithelial transformation, promoting angiogenesis, and polarizing M2 macrophages. Importantly, it mitigates adverse repair outcomes from inflammation and excessive collagen fiber deposition, ultimately restoring uterine glandular structures and thickness, thereby achieving the ultimate goal of restoring fertility and live birth rates. In conclusion, our study delineates a pioneering therapeutic approach leveraging the antioxidant properties of Ru-SAN to target ferroptosis, thereby offering an efficacious treatment for IUA.

Bagaza virus (BAGV) is a mosquito-borne flavivirus and has caused significant avian death in many regions, and also garnered recognition as a significant human pathogen causing diseases like encephalitis. The genome of BAGV encodes ten proteins including three structural proteins and seven nonstructural proteins. The C-terminus of the BAGV NS3 helicase serves as a helicase during BAGV replication, aiding in ATP hydrolysis and unwinding of double-stranded RNA. Here we determined the crystal structure of BAGV helicase and revealed the NTP and RNA binding pockets in the helicase which may be used for exploiting antiviral therapeutics. Using structure-based virtual screening, we discovered 20 compounds targeting both NTP and RNA binding pockets of the helicase. Molecular docking, mutation analysis, isothermal calorimetry (ITC) and the ATPase activity assay demonstrated that epigallocatechin-3-gallate (EGCG), and other top three screened compounds (Quercitrin, Citicoline sodium, Isochlorogenic acid C), showed binding affinities for both the NTP binding site and the RNA binding site of BAGV helicase, and inhibited the ATPase activity of the helicase. Taken together, our discovery of dual-target inhibitors provides a viable strategy for advancing innovative therapies against BAGV, as well as other flaviviruses.