Tribbles 3 deficiency promotes atherosclerotic fibrous cap thickening and macrophage-mediated extracellular matrix remodelling

Melatonin Inhibiting Neuronal Cells Ferroptosis Through Lipid Metabolic Reprogramming

This study aims to identify the underlying mechanism by which melatonin protects neurons. Firstly, the inhibitory effect of melatonin on ferroptosis was verified by treating HT22 cells with melatonin, Erastin, and Ferrostatin-1. Secondly, transcriptomic and metabolomic analyses were performed. Melatonin-related hub genes were identified by differential gene expression analysis, and lipid metabolism-related critical signaling pathways and biological processes (BPs) were determined by gene set enrichment analysis (GSEA). Finally, the expression of hub genes was verified by quantitative real-time PCR (qRT-PCR) or Western Blot (WB), and the involvement of Tribble 3 (Trib3) in the regulation of lipid metabolism and ferroptosis by melatonin was confirmed by Cell Counting Kit 8 (CCK-8) assay, ROS analysis, and WB. Assay results showed that melatonin significantly increased Gpx4 activity, decreased ROS generation, and inhibited ferroptosis in HT22 cells. The hub gene Trib3 was obtained by transcriptomic analysis, and its expression was upregulated with Erastin treatment. Lipid metabolomic analysis suggested that the regulation of lipid metabolism by melatonin was associated with glycerophospholipids. In vitro experiments showed that Trib3 was regulated by the upstream factor Atf4, and the protein levels of Trib3 and Atf4 were significantly increased after Erastin treatment. However, melatonin can reduce the protein levels of Trib3 and Atf4, increase the survival rate of HT-22 cells and the activity of GPX4, and reduce the ROS content. Melatonin inhibits neuronal ferroptosis by affecting the Atf4/Trib3 axis via the modulation of lipid metabolism.

Reprogramming human macrophages in symptomatic carotid stenosis: Stabilization of atherosclerotic carotid plaques

BACKGROUND AND AIMS

Inflammation is a precursor to atherosclerotic plaque destabilisation, leading to ischaemic events like stroke. Since macrophage phenotypes can be influenced by their microenvironment, we aimed to stabilise plaques and reduce the risk of recurrent ischaemic events using clinically relevant anti-inflammatory agents.

METHODS

Thirteen carotid plaques from stroke/Transient Ischaemic Attack (TIA) patients undergoing carotid endarterectomy were analysed using immunofluorescence stain to identify macrophage markers (CD68, CD86, MRC1). An in vitro model of human blood-derived macrophages was used to evaluate the effects of statins and glucocorticoids on macrophage-specific markers using RT-qPCR, Western Blot, and immunofluorescence staining. The physiological effects of dexamethasone on macrophages and human carotid plaques were further studied ex vivo.

RESULTS

The macrophage population (CD68+) in the carotid plaques was dominated by "double-positive" (CD86+MRC1+) macrophages (67.8 %), followed by "M1-like" (CD86+MRC1-) (16.5 %), "M2-like" (CD86-MRC1+) (8.7 %) and "double-negative" (CD86-MRC1-) (7.0 %) macrophages. M1-like macrophages were more prevalent in unstable plaque sections than stable ones (p = 0.0022). Exposure to dexamethasone increased macrophage MRC1 gene expression in vitro and ex vivo. It also reduced the expression of the Oxidised Low-Density Lipoprotein Receptor 1 (OLR1) gene and protein, leading to reduced oxLDL uptake in foam cell assays.

CONCLUSIONS

Clinically relevant concentrations of glucocorticoids may shift human macrophages to a less inflammatory state, thus reducing their ability for oxidised LDL uptake. In contrast, this anti-inflammatory mechanism was not observed in response to statins. These findings suggest that glucocorticoids could help prevent ischemic events in patients with advanced atherosclerosis.

TRIB3 Is a Hub Gene in Steatohepatitis and Aggravates Lipid Deposition and Inflammation in Hepatocytes

Background

Non-alcoholic fatty liver disease (NAFLD), also known as Metabolic dysfunction-associated fatty liver disease (MASLD), has become one of the most common chronic liver diseases worldwide, approximately 30% of adults and 70%~80% of patients with obesity and diabetes suffer from NAFLD.

Objective

We attempted to find a potential hub gene in NAFLD hepatocyte cell model induced by palmitic acid and oil acid (PAOA), and investigated the function of the hub-gene.

Methods

We searched and downloaded the GSE122660 dataset from GEO-DataSets, and differentially expressed genes (DEGs) were analyzed using R software. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to identify the significantly activated signaling pathways in steatohepatitis. A protein-protein interaction (PPI) network was constructed to identify hub genes among the DEGs. qRT-PCR, Western blotting, and Oil Red O staining were used to explore the function of hub genes in PAOA-induced hepatocytes in vitro.

Results

A total of 255 DEGs were identified in the GSE122660 dataset and were primarily associated with inflammation-and lipid metabolism-related pathways. The tribbles pseudokinase 3 (TRIB3) was highlighted as a hub gene. We found that TRIB3 was upregulated in CDHFDinduced NAFLD mouse liver tissue and hepatocyte cell models. Furthermore, TRIB3 aggravated PAOA-induced lipid accumulation and inflammation in hepatocytes in vitro.

Conclusion

The present study identified TRIB3 as a hub gene for steatohepatitis and aggravated lipid accumulation and inflammation in vitro. Therefore, targeting TRIB3 could be a potential pharmacological strategy for NAFLD treatment.

Development of an Endoplasmic Reticulum Stress-Related Diagnostic Signature in Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is a prevalent endocrine and metabolic disorder in premenopausal women. This investigation was to elucidate the underlying mechanism of endoplasmic reticulum stress (ERS) activation in granulosa cells, which has been implicated in the etiology of PCOS. Differentially expressed genes (DEGs) between PCOS and control groups were integrated with ERS gene lists from databases to identify DE-ERS genes, and functional analyses were performed. Univariate regression analysis and the LASSO method were used to select diagnostic factors, followed by establishing a DE-ERS gene-based diagnostic model. A nomogram model was further generated to predict the risk of PCOS. The correlation between ERS gene expression and immune cell proportion was assessed. A total of 14 DE-ERS genes associated with "protein processing in endoplasmic reticulum", "ferroptosis", and "glycerophospholipid metabolism" were selected as PCOS-related factors. An eight-DE-ERS genes-based diagnostic model was developed and displayed satisfactory performance in the training (Area under curve (AUC) = 0.983) and validation datasets (AUC = 0.802). High risk of PCOS can be accurately predicted, which might contribute to clinical decision-making. Moreover, EDEM1 expression was significantly positively correlated with naive B cell infiltration, while PDIA6 was negatively correlated with neutrophil proportion (P < 0.001). We identified eight novel molecules and developed an ERS gene-based diagnostic model in PCOS, which might provide novel insight for finding biomarkers and treatment methods.

tRNA-derived fragment tRF-30 propels diabetes-induced retinal microvascular complications by regulating STAT3 signaling

Transfer RNA-derived fragments (tRFs) represent a novel class of non-coding RNA transcripts that possess specific biological functions. However, the involvement of tRFs in retinal microvascular diseases remains poorly understood. In this study, we aimed to reveal whether modulation of tRF-30 expression could attenuate pathological retinal neovascular diseases. Our findings demonstrate a significant upregulation of tRF-30 expression levels in both in vivo models of diabetic retinopathy (DR) and in vitro endothelial sprouting models. Conversely, inhibition of tRF-30 expression suppressed the formation of abnormal neovascularization in the retina in vivo, while reducing the proliferation and migration activity of retinal vascular endothelial cells in vitro. We also found that tRF-30 modulates retinal neovascularization through the tRF-30/TRIB3/signal transducer and activated transcription 3 signaling pathway. Furthermore, we validated a significant upregulation of tRF-30 expression levels in the vitreous humor of DR patients, with high levels of both validity and specificity in diagnostic testing. Collectively, our findings highlight a pro-angiogenic role for tRF-30 in DR. Intervening in the tRF-30 signaling pathway may represent a promising prevention and treatment strategy for retinal angiogenesis.

Single-nuclei transcriptome analysis of channel catfish spleen provides insight into the immunome of an aquaculture-relevant species

The catfish industry is the largest sector of U.S. aquaculture production. Given its role in food production, the catfish immune response to industry-relevant pathogens has been extensively studied and has provided crucial information on innate and adaptive immune function during disease progression. To further examine the channel catfish immune system, we performed single-cell RNA sequencing on nuclei isolated from whole spleens, a major lymphoid organ in teleost fish. Libraries were prepared using the 10X Genomics Chromium X with the Next GEM Single Cell 3' reagents and sequenced on an Illumina sequencer. Each demultiplexed sample was aligned to the Coco_2.0 channel catfish reference assembly, filtered, and counted to generate feature-barcode matrices. From whole spleen samples, outputs were analyzed both individually and as an integrated dataset. The three splenic transcriptome libraries generated an average of 278,717,872 reads from a mean 8,157 cells. The integrated data included 19,613 cells, counts for 20,121 genes, with a median 665 genes/cell. Cluster analysis of all cells identified 17 clusters which were classified as erythroid, hematopoietic stem cells, B cells, T cells, myeloid cells, and endothelial cells. Subcluster analysis was carried out on the immune cell populations. Here, distinct subclusters such as immature B cells, mature B cells, plasma cells, γδ T cells, dendritic cells, and macrophages were further identified. Differential gene expression analyses allowed for the identification of the most highly expressed genes for each cluster and subcluster. This dataset is a rich cellular gene expression resource for investigation of the channel catfish and teleost splenic immunome.

The role of the CXCR6/CXCL16 axis in the pathogenesis of fibrotic disease

CXC chemokine receptor 6 (CXCR6), a seven-transmembrane domain G-protein-coupled receptor, plays a pivotal regulatory role in inflammation and tissue damage through its interaction with CXC chemokine ligand 16 (CXCL16). This axis is implicated in the pathogenesis of various fibrotic diseases and correlates with clinical parameters that indicate disease severity, activity, and prognosis in organ fibrosis, including afflictions of the liver, kidney, lung, cardiovascular system, skin, and intestines. Soluble CXCL16 (sCXCL16) serves as a chemokine, facilitating the migration and recruitment of CXCR6-expressing cells, while membrane-bound CXCL16 (mCXCL16) functions as a transmembrane protein with adhesion properties, facilitating intercellular interactions by binding to CXCR6. The CXCR6/CXCL16 axis is established to regulate the cycle of damage and repair during chronic inflammation, either through modulating immune cell-mediated intercellular communication or by independently influencing fibroblast homing, proliferation, and activation, with each pathway potentially culminating in the onset and progression of fibrotic diseases. However, clinically exploiting the targeting of the CXCR6/CXCL16 axis requires further elucidation of the intricate chemokine interactions within fibrosis pathogenesis. This review explores the biology of CXCR6/CXCL16, its multifaceted effects contributing to fibrosis in various organs, and the prospective clinical implications of these insights.