TCF7 is highly expressed in immune cells on the atherosclerotic plaques, and regulating inflammatory signaling via NFκB/AKT/STAT1 signaling.

Atherosclerosis, which is the fundamental basis for cardiovascular diseases in the global world, is driven by multiple roles of the immune system in the circulation and vascular plaque. Recent studies demonstrated that T-cell infiltrates into aorta plaque and plays an important role in recruiting macrophages to the vascular wall. Here, using single-cell sequencing, we found T cells in patients' plaques and differentially expressed genes (DEGs) of T cells in atherosclerosis mice. T cells and macrophages were continuously activated in atherosclerotic plaque in patients. Besides, other immune cells also take part in atherogenesis, such as natural killer (NK) cells, granulocytes. Interferon (IFN)/NFκB signaling, the AKT signaling pathway was highly activated in mouse (in vivo) and cell line (in vitro). TCF7 and XCL1 were regulated by AKT and NFκB, respectively through protein-protein network analysis. Therefore, we attempt to clarify and discover potential genes and new mechanisms associated with atherosclerosis for drug development.

Cholesterol 25-hydroxylase protects against experimental colitis in mice by modulating epithelial gut barrier function.

Cholesterol 25-hydroxylase (CH25H) encodes the enzyme that converts cholesterol to 25-hydroxycholesterol (25-HC). 25-HC has been demonstrated to be involved in the pathogenesis of inflammatory bowel disease. However, the role of CH25H in experimental colitis remains unknown. Dextran sulfate sodium (DSS)-induced colitis was monitored in wild type and Ch25h-/- mice in 8-week-old male for 7 days by assessment of body weight, histology, inflammatory cellular infiltration, and colon length. The function of CH25H was investigated using loss-of-function and gain-of-function such as Ch25h-deficient mice, supplementation with exogenous 25-HC and treatment of 25-HC into Caco2 and HCT116 colonic epithelial cells. Ch25h-/- mice with DSS-induced colitis exhibited aggravated injury, including higher clinical colitis scores, severe injury of the epithelial barrier, lower tight junction protein levels and higher levels of IL-6. Supplementation with exogenous 25-HC ameliorated disease symptoms and reduced the extent of damage in DSS-induced colitis, which was characterized by lower colon damage, higher tight junction protein expression, significantly decreased local and systemic production of pro-inflammatory cytokines IL-6. In Caco2 and HCT116 cells, 25-HC induced tight junction genes expression in colon cancer epithelial cells. These effects of CH25H were obtained by promoting ATF3 expression. Taken together, our findings reveal a protective role for 25-HC in DSS-induced colitis and the ability of CH25H to maintain epithelial gut barrier function through ATF3 expression. Supplementation with exogenous 25-HC ameliorates disease symptoms, which provides a new therapeutic strategy for ulcerative colitis.

STAT3 Regulates Mouse Neural Progenitor Proliferation and Differentiation by Promoting Mitochondrial Metabolism.

The proliferation and differentiation of neural progenitor lay the foundation for brain development. In neural progenitors, activation of Signal Transducer and Activator of Transcription 3 (STAT3) has been found to promote proliferation and astrocytogenesis while suppressing neurogenesis. However, our study found that Stat3 conditional knockout in neural progenitors (Stat3 cKO) also results in increased proliferation and suppressed neurogenesis. To investigate how STAT3 regulates these processes, we attempted to identify potential STAT3 target genes by RNA-seq profiling of the control (CTL) and Stat3 cKO neural progenitors. We found that STAT3 promotes the expression of genes involved in the mitochondrial oxidative phosphorylation (OXPHOS), and thereby promotes mitochondrial respiration and negatively regulates reactive oxygen species (ROS) production. In addition, we demonstrated that Stat3 loss-of-function promotes proliferation via regulation of mitochondrial metabolism and downstream signaling pathways. Our study provides novel insights into the relation between STAT3, mitochondrial metabolism and the process of embryonic neurogenesis.