关键词： Tianhuang formula   Non-alcoholic fatty liver diseases   Type 2 diabetes mellitus   CRLS1-ATF3/ChREBP pathway  

摘要： Objective Tianhuang Formula (THF) is a hospital formula summarized by Professor Jiao Guo's 30 years of clinical experience. Some studies have shown that it can alleviate dyslipidemia in the body. The purpose of this study is to confirm whether THF can improve non-alcoholic fatty liver diseases (NAFLD) in type 2 diabetic mice induced by high-fat diet (HFD)/streptomycin (STZ) and to clarify its potential mechanism. Methods After induction of diabetes, mice were administrated with THF (60 ​mg/kg or 120 ​mg/kg) once daily for 10 weeks. Blood glucose (FBG), glucose tolerance, and insulin resistance (IR) were assayed by oral glucose tolerance test (OGTT) and insulin tolerance test (ITT). Blood lipids, alanine transaminase (ALT), and aspartate transaminases (AST) were detected. Serum fasting insulin (INS) and adiponectin (APN) levels were measured using ELISA. Histological changes in liver and pancreatic islets were observed by H&E staining, followed by Oil Red O staining for liver lipid quantification and periodic acid-Schiff (PAS) staining to detect glycogen accumulation. Western blotting detected the levels of fatty cardiolipin synthase 1 (CRLS1), transcription factor activator 3 (ATF3), and carbohydrate-responsive element binding protein (ChREBP) in the liver. The mRNA transcripts of hepatic inflammatory factors, lipogenesis and lipolysis-related genes, and gluconeogenic enzyme-phosphoenolpyruvate carboxykinase (PEPCK), CRLS1, ATF3, and ChREBP mRNA levels were evaluated by RT-qPCR. Results THF restored impaired glucose tolerance and insulin resistance, respectively. There was an improvement in HFD/STZ-induced liver and islet damage, high serum HDL-C and ANP levels, and a significant decrease in FBG, total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), FFA, INS, ALT, and AST, and lipid droplet counts in the T2DM mice treated with THF. CREBBP binding protein ATF3 mediated the insulin resistance signaling pathway, which regulated glucos

关键词： ECM   RNAseq   Cell cycling   Mechanotransduction   Proliferation   Rigidity  

摘要： The Rho family GTPases Rac and Rho play critical roles in transmitting mechanical information contained within the extracellular matrix (ECM) to the cell. Rac and Rho have well-described roles in regulating stiffness-dependent actin remodeling, proliferation and motility. However, much less is known about the relative roles of these GTPases in stiffness-dependent transcription, particularly at the genome-wide level. Here, we selectively inhibited Rac and Rho in mouse embryonic fibroblasts cultured on deformable substrata and used RNA sequencing to elucidate and compare the contribution of these GTPases to the early transcriptional response to ECM stiffness. Surprisingly, we found that the stiffness-dependent activation of Rac was dominant over Rho in the initial transcriptional response to ECM stiffness. We also identified activating transcription factor 3 (ATF3) as a major target of stiffness-and Rac-mediated signaling and show that ATF3 repression by ECM stiffness helps to explain how the stiffness-dependent activation of Rac results in the induction of cyclin D1.

关键词： circRNA   hepatocellular carcinoma   N-6-methyladenosine modification   mRNA decay   protein encoding   RNA-binding protein  

摘要： Background: Circular RNAs (circRNAs) play a significant role in the initiation and progression of various cancers, including hepatocellular carcinoma (HCC). Circular syntaxin 6 (circSTX6, also known as hsa_circ_0007905) has been identified as a microRNA (miRNA) sponge in pancreatic adenocarcinoma. However, its full range of functions in terms of protein scaffold and translation remain largely unexplored in the context of ***: The expression of circSTX6 and its encoded protein was examined in HCC tumour tissues. N-6 -methyladenosine (m(6) A) on circSTX6 was verified and quantified by methylated RNA immunoprecipitation (Me-RIP), RIP and dual luciferase reporter assays. The biological functions of circSTX6 and its encoded protein in HCC were clarified by in vitro and in vivo experiments. Mechanistically, the interaction between circSTX6 and heterogeneous nuclear ribonucleoprotein D (HNRNPD) was investigated by RNA pull-down, RIP and fluorescence in situ hybridization (FISH)/IF. The regulatory effects of circSTX6 and HNRNPD on activating transcription factor 3 (ATF3) mRNA were determined by mRNA stability and RIP assays. Furthermore, the presence of circSTX6-encoded protein was verified by mass ***: CircSTX6 and its encoded 144 amino acid polypeptide, circSTX6-144aa, were highly expressed in HCC tumour tissues and served as independent risk factors for overall survival in HCC patients. The expression of circSTX6 was regulated by METTL14 in an m(6) A-dependent manner. Functionally, circSTX6 accelerated HCC proliferation and tumourigenicity and reinforced tumour metastasis in vitro and in vivo. Mechanistically, circSTX6 acted as a sponge for HNRNPD protein, facilitating its binding to ATF3 mRNA, consequently promoting ATF3 mRNA decay. Meanwhile, circSTX6-144aa promoted HCC proliferation, migration and invasion independent of circSTX6 ***: Collectively, our study reveals that m(6) A-modified circSTX6 drives malignancy in HCC through t

关键词： Non-alcoholic fatty liver disease   E6446   ATF3   Liver-adipose axis  

摘要： Due to the complexity and incomplete understanding of the crosstalk between liver and adipose tissue, especially the processes of hepatic lipogenesis and adipogenic differentiation, there are currently no effective drugs for the treatment of nonalcoholic fatty liver disease (NAFLD). Stearoyl-coenzyme A desaturase 1 (SCD1), which is abundantly expressed in liver and adipose tissue, may mediate the cross-talk between liver and adipose tissue. Thus, it is essential to develop specific SCD1 inhibitors that target the liver-adipose axis. Herein, we identified a novel SCD1 inhibitor, E6446, through a high-throughput virtual screen. E6646 significantly inhibited adipogenic differentiation and hepatic lipogenesis via SCD1-ATF3 signaling. The SPR results showed that E6446 had a strong interaction ability with SCD1 (KD:4.61 mu M). Additionally, E6646 significantly decreased hepatic steatosis, hepatic lipid droplet accumulation and insulin resistance in high-fat diet (HFD)-fed mice. Taken together, our findings not only suggest that E6446 can serve as a new, safe and highly effective anti-NAFLD agent for future clinical use but also provide a molecular basis for the future development of SCD1 inhibitors that inhibit both adipogenic differentiation and hepatic lipogenesis.-_fLbJcbqbtKciFUEE_QdNVideo Abstract

关键词： Saikosaponin A   Hepatocellular carcinoma   Ferroptosis   ATF3  

摘要： Ferroptosis is a type of nonapoptotic necrotic cell death characterized by iron-dependent lipid peroxidation. Saikosaponin A (SsA), a natural bioactive triterpenoid saponin extracted from Radix Bupleuri, has shown potent antitumor activity against various tumors. However, the underlying mechanism of the antitumor activity of SsA remains unclear. Here, we discovered that SsA induced HCC cell ferroptosis in vitro and in vivo. Using RNA-sequence analysis, we found that SsA mainly affected the glutathione metabolic pathway and inhibited the expression of cystine transporter solute carrier family 7 member 11 (SLC7A11). Indeed, SsA increased intracellular malondialdehyde (MDA) and iron accumulation, while it decreased the levels of reduced glutathione (GSH) in HCC. Deferoxamine (DFO), ferrostatin-1 (Fer-1) and GSH could rescue SsA-induced cell death, whereas Z-VAD-FMK was found ineffective in inhibiting SsAinduced cell death in HCC. Importantly, our result indicated that SsA induced the expression of activation transcription factor 3 (ATF3). SsA-induced cell ferroptosis and suppression of SLC7A11 are dependent on ATF3 in HCC. Moreover, we revealed that SsA induced ATF3 upregulation via activation of endoplasmic reticulum (ER) stress. Taken together, our findings support that ATF3-dependent cell ferroptosis mediated the antitumor effects of SsA, opening the possibility to explore SsA as a ferroptosis inducer in HCC. & COPY;2023 Elsevier Inc. All rights reserved.

关键词： scRNA-seq   Macrophage   Transcription factor  

摘要： The dorsal root ganglion (DRG) is actively involved in the development of neuropathic pain (NP), serving as an intermediate station for pain signals from the peripheral nervous system to the central nervous system. The mechanism by which DRG is involved in NP regulation is not fully understood. The immune system plays a pivotal role in the physiological and pathological states of the human body. In recent years, the immune system has been thought to play an increasingly important role in the pathogenesis of NP. The immune system plays a key role in pain through specific immune cells and their immune-related genes (IRGs). However, the mechanism by which IRGs of DRG regulate NP action has not been fully ***, we performed Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of IRGs in DRG bulk-RNA sequencing data from spared nerve injury (SNI) model mice and found that their IRGs were enriched in many pathways, especially in the immune response pathway. Subsequently, we analyzed single cell RNA sequencing (scRNA-seq) data from DRGs extracted from the SNI model and identified eight cell populations. Among them, the highest IRG activity was presented in macrophages. Next, we analyzed the scRNA and bulk-sequencing data and deduced five common transcription factors (TFs) from differentially expressed genes (DEGs). The protein-protein interaction (PPI) network suggested that Atf3 and JunB are closely related. In vitro experiments, we verified that the protein and mRNA expressions of Atf3 and JunB were up-regulated in macrophages after lipopolysaccharide (LPS) stimulation. Moreover, the down-regulation of Atf3 reduced the release of inflammatory cytokines and decreased the protein and mRNA expression levels of JunB. The down-regulation of JunB also reduced the release of inflammatory cytokines. Furthermore, overexpression of JunB attenuated the effect of Atf3 down-regulation in reducing the release of inflammatory cytokines. Therefor

关键词： Small cell lung cancer   Shikonin   Ferroptosis   ATF3   ROS   Histone acetylation  

摘要： Small cell lung cancer (SCLC) is a subtype of lung cancer with a very poor overall survival rate due to its extremely high proliferation and metastasis predilection. Shikonin is an active ingredient extracted from the roots of Lithospermum erythrorhizon, and exerts multiple anti-tumor functions in many cancers. In the present study, the role and underlying mechanism of shikonin in SCLC were investigated for the first time. We found that shikonin effectively suppressed cell proliferation, apoptosis, migration, invasion, and colony formation and slightly induced apoptosis in SCLC cells. Further experiment indicated the shikonin could also induced ferroptosis in SCLC cells. Shikonin treatment effectively suppressed the activation of ERK, the expression of ferroptosis inhibitor GPX4, and elevated the level of 4-HNE, a biomarker of ferroptosis. Both total ROS and lipid ROS were increased, while the GSH levels were decreased in SCLC cells after shikonin treatment. More importantly, our data identified that the function of shikonin was dependent on the up-regulation of ATF3 by performing rescue experiments using shRNA to silence the expression of ATF3, especially in the total and lipid ROS accumulaiton. Xenograft model was established using SBC-2 cells, and the results revealed that shikonin also significantly inhibited tumor growth by inducing ferroptosis. Finally, our data further confirmed that shikonin activated ATF3 transcription by impairing the recruitment of HDAC1 mediated by c-myc on the ATF3 promoter, and subsequently elevating of histone acetylation. Our data documented that shikonin suppressed SCLC by inducing ferroptosis in a ATF3-dependent manner. Shikonin upregulated the expression of ATF3 expression via promoting the histone acetylation by inhibiting c-myc-mediated HDAC1 binding on ATF3 promoter.