STIM1-mediated NFAT signaling synergizes with STAT1 to control T-bet expression and TH1 differentiation
Related Articles
STAT1 mediates the pro-inflammatory role of GBP5 in colitis
Previous studies establish guanylate binding protein 5 (GBP5) as a driver in the development of inflammatory bowel diseases (IBDs). Here, we aim to elucidate the mechanism underlying the pro-inflammatory role of GBP5. We observe that loss of Gbp5 causes reduced colonic inflammation and decreased numbers of innate lymphoid cells (ILCs) in colitis mice. The transcriptional alterations observed in GBP5-deficient THP-1 cells mirrored those triggered by STAT1 activation, leading to the findings that GBP5 is essential for the stimulated expression of STAT1 and its downstream effectors, including cytokines that drive the expansion of ILCs. Remarkably, over-expression of STAT1 reverses the reduced cytokine expression caused by GBP5 deficiency. While GBP5 does not directly drive gene transcription, it binds with STAT1 and facilitates its nuclear translocation, thereby enhancing the expression of STAT1 itself and its downstream effectors. Overall, GBP5 plays a pro-inflammatory role in IBD by enhancing the activity and expression of STAT1.
Sodium oligomannate disrupts the adherence of Ribhigh bacteria to gut epithelia to block SAA-triggered Th1 inflammation in 5XFAD transgenic mice
Sodium oligomannate (GV-971), an oligosaccharide drug approved in China for treating mild-to-moderate Alzheimer’s disease (AD), was previously found to recondition the gut microbiota and limit altered peripheral Th1 immunity in AD transgenic mice. As a follow-up study, we here made advances by pinpointing a Lactobacillus murinus (L.m.) strain that highly expressed a gene encoding a putative adhesin containing Rib repeats (Ribhigh–L.m.) particularly enriched in 5XFAD transgenic mice. Mechanistically, Ribhigh–L.m. adherence to the gut epithelia upregulated fecal metabolites, among which lactate ranked as the top candidate. Excess lactate stimulated the epithelial production of serum amyloid A (SAA) in the gut via the GPR81-NFκB axis, contributing to peripheral Th1 activation. Moreover, GV-971 disrupted the adherence of Ribhigh–L.m. to gut epithelia via direct binding to Rib, which corrected the excess lactate, reduced SAA, and alleviated Th1-skewed inflammation. Together, we gained further insights into the molecular link between gut bacteria and AD progression and the mechanism of GV-971 in treating AD.
Iron homeostasis and ferroptosis in muscle diseases and disorders: mechanisms and therapeutic prospects
The muscular system plays a critical role in the human body by governing skeletal movement, cardiovascular function, and the activities of digestive organs. Additionally, muscle tissues serve an endocrine function by secreting myogenic cytokines, thereby regulating metabolism throughout the entire body. Maintaining muscle function requires iron homeostasis. Recent studies suggest that disruptions in iron metabolism and ferroptosis, a form of iron-dependent cell death, are essential contributors to the progression of a wide range of muscle diseases and disorders, including sarcopenia, cardiomyopathy, and amyotrophic lateral sclerosis. Thus, a comprehensive overview of the mechanisms regulating iron metabolism and ferroptosis in these conditions is crucial for identifying potential therapeutic targets and developing new strategies for disease treatment and/or prevention. This review aims to summarize recent advances in understanding the molecular mechanisms underlying ferroptosis in the context of muscle injury, as well as associated muscle diseases and disorders. Moreover, we discuss potential targets within the ferroptosis pathway and possible strategies for managing muscle disorders. Finally, we shed new light on current limitations and future prospects for therapeutic interventions targeting ferroptosis.
Integrated proteogenomic characterization of ampullary adenocarcinoma
Ampullary adenocarcinoma (AMPAC) is a rare and heterogeneous malignancy. Here we performed a comprehensive proteogenomic analysis of 198 samples from Chinese AMPAC patients and duodenum patients. Genomic data illustrate that 4q loss causes fatty acid accumulation and cell proliferation. Proteomic analysis has revealed three distinct clusters (C-FAM, C-AD, C-CC), among which the most aggressive cluster, C-AD, is associated with the poorest prognosis and is characterized by focal adhesion. Immune clustering identifies three immune clusters and reveals that immune cluster M1 (macrophage infiltration cluster) and M3 (DC cell infiltration cluster), which exhibit a higher immune score compared to cluster M2 (CD4+ T-cell infiltration cluster), are associated with a poor prognosis due to the potential secretion of IL-6 by tumor cells and its consequential influence. This study provides a comprehensive proteogenomic analysis for seeking for better understanding and potential treatment of AMPAC.
Type 2 immunity in allergic diseases
Significant advancements have been made in understanding the cellular and molecular mechanisms of type 2 immunity in allergic diseases such as asthma, allergic rhinitis, chronic rhinosinusitis, eosinophilic esophagitis (EoE), food and drug allergies, and atopic dermatitis (AD). Type 2 immunity has evolved to protect against parasitic diseases and toxins, plays a role in the expulsion of parasites and larvae from inner tissues to the lumen and outside the body, maintains microbe-rich skin and mucosal epithelial barriers and counterbalances the type 1 immune response and its destructive effects. During the development of a type 2 immune response, an innate immune response initiates starting from epithelial cells and innate lymphoid cells (ILCs), including dendritic cells and macrophages, and translates to adaptive T and B-cell immunity, particularly IgE antibody production. Eosinophils, mast cells and basophils have effects on effector functions. Cytokines from ILC2s and CD4+ helper type 2 (Th2) cells, CD8 + T cells, and NK-T cells, along with myeloid cells, including IL-4, IL-5, IL-9, and IL-13, initiate and sustain allergic inflammation via T cell cells, eosinophils, and ILC2s; promote IgE class switching; and open the epithelial barrier. Epithelial cell activation, alarmin release and barrier dysfunction are key in the development of not only allergic diseases but also many other systemic diseases. Recent biologics targeting the pathways and effector functions of IL4/IL13, IL-5, and IgE have shown promising results for almost all ages, although some patients with severe allergic diseases do not respond to these therapies, highlighting the unmet need for a more detailed and personalized approach.
Responses