Dioscin decreases M2 polarization via inhibiting a positive feedback loop between RBM47 and NF-κB in glioma.

BACKGROUND: The role of the glioblastoma (GBM) microenvironment is pivotal in the development of gliomas. Discovering drugs that can traverse the blood-brain barrier and modulate the tumor microenvironment is crucial for the treatment of GBM. Dioscin, a steroidal saponin derived from various kinds of plants and herbs known to penetrate the blood-brain barrier, has shown its powerful anti-tumor activity. However, little is known about its effects on GBM microenvironment. METHODS: Bioinformatics analysis was conducted to assess the link between GBM patients and their prognosis. Multiple techniques, including RNA sequencing, immunofluorescence staining, Western blot analysis, RNA-immunoprecipitation (RIP) assays, and Chromatin immunoprecipitation (CHIP) analysis were employed to elucidate the mechanism through which Dioscin modulates the immune microenvironment. RESULTS: Dioscin significantly impaired the polarization of macrophages into the M2 phenotype and enhanced the phagocytic ability of macrophages in vitro and in vivo. A strong correlation between high expression of RBM47 in GBM and a detrimental prognosis for patients was demonstrated. RNA-sequencing analysis revealed an association between RBM47 and the immune response. The inhibition of RBM47 significantly impaired the recruitment and polarization of macrophages into the M2 phenotype and enhanced the phagocytic ability of macrophages. Moreover, RBM47 could stabilize the mRNA of inflammatory genes and enhance the expression of these genes by activating the NF-κB pathway. In addition, NF-κB acts as a transcription factor that enhances the transcriptional activity of RBM47. Notably, we found that Dioscin could significantly inhibit the activation of NF-κB and then downregulate the expression of RBM47 and inflammatory genes protein. CONCLUSION: Our study reveals that the positive feedback loop between RBM47 and NF-κB could promote immunosuppressive microenvironment in GBM. Dioscin effectively inhibits M2 polarization in GBM by disrupting the positive feedback loop between RBM47 and NF-κB, indicating its potential therapeutic effects in GBM treatment.

Thermal insulating, light-weight and conductive cellulose/aramid nanofibers composite aerogel for pressure sensing.

Conductive nanocellulose aerogels have attracted significant attention in pressure sensing for wearable devices owing to lightweight, sustainability and good chemical stability. Limited by its flammability and weak mechanical properties, aramid nanofiber (ANF) was designed as reinforcement to overcome the shortcoming mentioned above. Herein, the unidirectional freeze casting method was proposed to fabricate nanocellulose/aramid nanofiber (CA) aerogel. Then, the CA/PPy (CAP) aerogel was obtained by using the oriented structure of CA aerogel as a template for inducing conductive polypyrrole (PPy) in-situ formation inside the composite aerogel. The conductive aerogel with the ordered microstructure exhibited the anisotropic mechanical properties and thermal conductivity. And it could withstand high temperature without any destruction phenomenon. Moreover, the aerogel sensor revealed high strain sensitivity and satisfactory electrochemical performance. Lightweight CAP aerogel with controllable alignment, sensitive sensing property and thermal stability is very promising in pressure sensor under some extreme conditions.