LINC01002 functions as a ceRNA to regulate FRMD8 by sponging miR-4324 for the development of COVID-19.

BACKGROUND: Syndrome coronavirus-2 (SARS-CoV-2) has developed various strategies to evade the antiviral impact of type I IFN. Non-structural proteins and auxiliary proteins have been extensively researched on their role in immune escape. Nevertheless, the detailed mechanisms of structural protein-induced immune evasion have not been well elucidated. METHODS: Human alveolar basal epithelial carcinoma cell line (A549) was stimulated with polyinosinic-polycytidylic acid (PIC) and independently transfected with four structural proteins expression plasmids, including nucleocapsid (N), spike (S), membrane (M) and envelope (E) proteins. By RT-qPCR and ELISA, the structural protein with the most pronounced inhibitory effects on IFN-ß induction was screened. RNA-sequencing (RNA-Seq) and two differential analysis strategies were used to obtain differentially expressed genes associated with N protein inhibition of IFN-ß induction. Based on DIANA-LncBase and StarBase databases, the interactive competitive endogenous RNA (ceRNA) network for N protein-associated genes was constructed. By combining single-cell sequencing data (GSE158055), lncRNA-miRNA-mRNA axis was further determined. Finally, RT-qPCR was utilized to illustrate the regulatory functions among components of the ceRNA axis. RESULTS: SARS-CoV-2 N protein inhibited IFN-ß induction in human alveolar epithelial cells most significantly compared with other structural proteins. RNA-Seq data analysis revealed genes related to N protein inhibiting IFNs induction. The obtained 858 differentially expressed genes formed the reliable ceRNA network. The function of LINC01002-miR-4324-FRMD8 axis in the IFN-dominated immune evasion was further demonstrated through integrating single-cell sequencing data. Moreover, we validated that N protein could reverse the effect of PIC on LINC01002, FRMD8 and miR-4324 expression, and subsequently on IFN-ß expression level. And LINC01002 could regulate the production of FRMD8 by inhibiting miR-4324. CONCLUSION: SARS-CoV-2 N protein suppressed the induction of IFN-ß by regulating LINC01002 which was as a ceRNA, sponging miR-4324 and participating in the regulation of FRMD8 mRNA. Our discovery provides new insights into early intervention therapy and drug development on SARS-CoV-2 infection.

[Exploring the Role of PCDHGB4 in the Occurrence of Lung Squamous Cell Carcinoma Based on Bioinformatics Analysis].

BACKGROUND: Lung squamous cell carcinoma (LUSC) is a subtypes of non-small cell lung cancer (NSCLC). It has been reported that members of the protocadherin γ family can regulate tumor cell growth by inhibiting the Wnt signaling pathway. Protocadherin-gamma subfamily B4 (PCDHGB4) as a family member in LUSC was rarely reported. The aim of this study was to investigate the role and potential prognostic value of PCDHGB4 in the development of LUSC using bioinformatics methods. METHODS: The Cancer Genome Atlas (TCGA), cBioPortal and UALCAN databases were used to analyze the expression, prognosis, clinicopathological features, immune cell infiltration, immune regulatory genes, immune checkpoint inhibitors (ICIs), and methyltransferases of PCDHGB4 in LUSC. At the single cell level, we analyzed the clustering results of cell subtypes and the expression of PCDHGB4 in different immune cell subpopulations. In addition, we compared the promoter methylation levels of PCDHGB4 in LUSC tissues and normal tissues and performed protein-protein interaction and mutation analysis. Finally, enrichment analysis was performed based on the differentially expressed genes. RESULTS: Bioinformatics analysis results showed that the expression level of PCDHGB4 in LUSC tissues was lower than that in normal tissues. Survival analysis showed that increased PCDHGB4 expression was associated with poor prognosis. Single-cell sequencing analysis showed that PCDHGB4 was expressed in T cells, monocytes or macrophages, and dendritic cells. It was further found that PCDHGB4 played an important role in tumor immunity and confirmed that PCDHGB4 was associated with immune checkpoints, immune regulatory genes, and methyltransferases. Besides, enrichment analysis revealed that PCDHGB4 was involved in multiple cancer-related pathways. CONCLUSIONS: The expression of PCDHGB4 was low in LUSC. PCDHGB4 was related to the poor prognosis of patients, and PCDHGB4 was closely related to the infiltration and pathway of tumor immune cells. PCDHGB4 may be a potential prognostic marker and a new target for immunotherapy in LUSC.

USP7 as an emerging therapeutic target: A key regulator of protein homeostasis.

Maintaining protein balance within a cell is essential for proper cellular function, and disruptions in the ubiquitin-proteasome pathway, which is responsible for degrading and recycling unnecessary or damaged proteins, can lead to various diseases. Deubiquitinating enzymes play a vital role in regulating protein homeostasis by removing ubiquitin chains from substrate proteins, thereby controlling important cellular processes, such as apoptosis and DNA repair. Among these enzymes, ubiquitin-specific protease 7 (USP7) is of particular interest. USP7 is a cysteine protease consisting of a TRAF region, catalytic region, and C-terminal ubiquitin-like (UBL) region, and it interacts with tumor suppressors, transcription factors, and other key proteins involved in cell cycle regulation and epigenetic control. Moreover, USP7 has been implicated in the pathogenesis and progression of various diseases, including cancer, inflammation, neurodegenerative conditions, and viral infections. Overall, characterizing the functions of USP7 is crucial for understanding the pathophysiology of diverse diseases and devising innovative therapeutic strategies. This article reviews the structure and function of USP7 and its complexes, its association with diseases, and its known inhibitors and thus represents a valuable resource for advancing USP7 inhibitor development and promoting potential future treatment options for a wide range of diseases.

Silencing of catalase reduces unfavorable low-temperature tolerance capacity in whiteflies.

BACKGROUND: Temperature is a primary factor that determines the eco-geographical distribution and population development of invasive insects. Temperature stress leads to various negative effects, including excess reactive oxygen species (ROS), and catalase (CAT) is a key enzyme against ROS in the antioxidant pathway. The whitefly Bemisia tabaci MED is a typical invasive pest that causes damage worldwide. Our previous studies have shown that CAT promotes whitefly adaptation to high temperature by eliminating ROS. However, the mechanism underlying the low-temperature adaptation of whiteflies is still unknown. RESULTS: In this study, we investigated the role of CAT in the low-temperature tolerance of B. tabaci MED by analyzing its survival rate, reproduction, and ROS levels at 25 °C (as a control, suitable temperature), 20 °C (moderately decreased temperature), and 4 °C (severely decreased temperature). Silencing of BtCAT1, BtCAT2, or BtCAT3 reduced the viability of whiteflies under a short-term severely decreased temperature (4 °C), which manifested as decreases in survival and fecundity accompanied by significant increases in ROS levels. Moreover, even at a moderately decreased temperature (20 °C), silencing of BtCAT1 led to high ROS levels and low survival rates in adults. CONCLUSION: Silencing of BtCATs significantly increased the sensitivity of B. tabaci MED to low temperatures. BtCAT1 is likely more essential than other BtCATs for low-temperature tolerance in whiteflies. © 2024 Society of Chemical Industry.

Gut microbiome and antibiotic resistance effects during travelers' diarrhea treatment and prevention.

IMPORTANCE: The travelers' gut microbiome is potentially assaulted by acute and chronic perturbations (e.g., diarrhea, antibiotic use, and different environments). Prior studies of the impact of travel and travelers' diarrhea (TD) on the microbiome have not directly compared antibiotic regimens, and studies of different antibiotic regimens have not considered travelers' microbiomes. This gap is important to be addressed as the use of antibiotics to treat or prevent TD-even in moderate to severe cases or in regions with high infectious disease burden-is controversial based on the concerns for unintended consequences to the gut microbiome and antimicrobial resistance (AMR) emergence. Our study addresses this by evaluating the impact of defined antibiotic regimens (single-dose treatment or daily prophylaxis) on the gut microbiome and resistomes of deployed servicemembers, using samples collected during clinical trials. Our findings indicate that the antibiotic treatment regimens that were studied generally do not lead to adverse effects on the gut microbiome and resistome and identify the relative risks associated with prophylaxis. These results can be used to inform therapeutic guidelines for the prevention and treatment of TD and make progress toward using microbiome information in personalized medical care.

METTL3 regulates glucose transporter expression in placenta exposed to hyperglycemia through the mTOR signaling pathway.

BACKGROUND: Alterations in the placental expression of glucose transporters (GLUTs), the crucial maternal-fetal nutrient transporters, have been found in women with hyperglycemia in pregnancy (HIP). However, there is still uncertainty about the underlying effect of the high-glucose environment on placental GLUTs expression in HIP. METHODS: We quantitatively evaluated the activity of mammalian target of rapamycin (mTOR) and expression of GLUTs (GLUT1, GLUT3, and GLUT4) in the placenta of women with normal pregnancies (CTRL, n = 12) and pregnant women complicated with poorly controlled type 2 diabetes mellitus (T2DM, n = 12) by immunohistochemistry. In addition, BeWo cells were treated with different glucose concentrations to verify the regulation of hyperglycemia. Then, changes in the expression of GLUTs following the activation or suppression of the mTOR pathway were also assessed using MHY1485/rapamycin (RAPA) treatment or small interfering RNA (siRNA)-mediated silencing approaches. Moreover, we further explored the alteration and potential upstream regulatory role of methyltransferase-like 3 (METTL3) when exposed to hyperglycemia. RESULTS: mTOR, phosphorylated mTOR (p-mTOR), and GLUT1 protein levels were upregulated in the placenta of women with T2DM compared with those CTRL. In BeWo cells, mTOR activity increased with increasing glucose concentration, and the expression of GLUT1, GLUT3, and GLUT4 as well as GLUT1 cell membrane translocation were upregulated by hyperglycemia to varying degrees. Both the drug-mediated and genetic depletion of mTOR signaling in BeWo cells suppressed GLUTs expression, whereas MHY1485-induced mTOR activation upregulated GLUTs expression. Additionally, high glucose levels upregulated METTL3 expression and nuclear translocation, and decreasing METTL3 levels suppressed GLUTs expression and mTOR activity and vice versa. Furthermore, in METTL3 knockdown BeWo cells, the inhibitory effect on GLUTs expression was eliminated by activating the mTOR signaling pathway using MHY1485. CONCLUSION: High-glucose environment-induced upregulation of METTL3 in trophoblasts regulates the expression of GLUTs through mTOR signaling, contributing to disordered nutrient transport in women with HIP.

Multi-omics analysis reveals hepatic lipid metabolism profiles and serum lipid biomarkers upon indoor relevant VOC exposure.

As a widespread indoor air pollutant, volatile organic compound (VOC) caused various adverse health effects, especial the damage to liver, which has become a growing public concern. However, the current toxic data are intrinsically restricted in the single or major VOC species. Limited knowledge is available regarding toxic effects, biomarkers and underlying mechanisms of real indoor VOC-caused liver damage. Herein, an indoor relevant VOC exposure model was established to evaluate the hepatic adverse outcomes. Machine learning and multi-omics approaches, including liver lipidomic, serum lipidomic and liver transcriptomic, were utilized to uncover the characteristics of liver damage, serum lipid biomarkers, and involved mechanism stimulated by VOC exposure. The result showed that indoor relevant VOC led to the abnormal hepatic lipid metabolism, mainly manifested as a decrease in triacylglycerol (TG) and its precursor substance diacylglycerol (DG), which could be contributed to the occurrence of hepatic adverse outcomes. In terms of serum lipid biomarkers, five lipid biomarkers in serum were uncovered using machine learning to reflect the hepatic lipid disorders induced by VOC. Multi-omics approaches revealed that the upregulated Dgkq disturbed the interconversion of DG and phosphatidic acid (PA), leading to a TG downregulation. The in-depth analysis revealed that VOC down-regulated FoxO transcription factor, contributing to the upregulation of Dgkq. Hence, this study can provide valuable insights into the understanding of liver damage caused by indoor relevant VOC exposure model VOC exposure, from the perspective of multi-omics analysis.

Elevated galectin-3 levels detected in women with hyperglycemia during early and mid-pregnancy antagonizes high glucose - induced trophoblast cells apoptosis via galectin-3/foxc1 pathway.

OBJECTIVE: This study was to evaluate plasma galectin-3 levels from early pregnancy to delivery and explore the effects of galectin-3 on the function of trophoblast cells under high glucose exposure. METHODS: The plasma galectin-3 levels were quantified by enzyme-linked immunosorbent assay (ELISA) in the China National Birth Cohort (CNBC) at Peking University First Hospital, and the underlying signaling pathway was identified by protein-protein interaction (PPI) analysis, gene set enrichment analysis (GSEA), quantitative PCR (qPCR), western blotting, small interfering RNA (siRNA) transfections, and flow cytometry. RESULTS: Significantly higher galectin-3 levels were found in patients with gestational diabetes mellitus (GDM group; n = 77) during the first and second trimesters than that in healthy pregnant women (HP group; n = 113) (P < 0.05). No significant differences in plasma galectin-3 levels were detected between GDM and HP groups in maternal third-trimester blood and cord blood. PPI analysis suggested potential interactions between galectin-3 and foxc1. The findings of GSEA showed that galectin-3 was involved in the cytochrome P450-related and complement-related pathways, and foxc1 was associated with type I diabetes mellitus. Additionally, high glucose (25 mM) significantly increased the expression levels of galectin-3 and foxc1 and induced apoptosis in HTR-8/SVneo cells. Further in vitro experiments showed that galectin-3/foxc1 pathway could protect HTR-8/SVneo cells against high glucose - induced apoptosis. CONCLUSION: Future studies were required to validate whether plasma galectin-3 might become a potential biomarker for hyperglycemia during pregnancy. Elevated galectin-3 levels might be a vital protective mechanism among those exposed to hyperglycemia during pregnancy.

Fluid Thermodynamic Simulation of Ti-6Al-4V Alloy in Laser Wire Deposition.

A 3D numerical model of heat transfer and fluid flow of molten pool in the process of laser wire deposition was presented by computational fluid dynamics technique. The simulation results of the deposition morphology were also compared with the experimental results under the condition of liquid bridge transfer mode. Moreover, they showed a good agreement. Considering the effect of recoil pressure, the morphology of the deposit metal obtained by the simulation was similar to the experiment result. Molten metal at the wire tip was peeled off and flowed into the molten pool, and then spread to both sides of the deposition layer under the recoil pressure. In addition, the results of simulation and high-speed charge-coupled device presented that a wedge transition zone, with a length of ∼6 mm, was formed behind the keyhole in the liquid bridge transfer process, where the height of deposited metal decreased gradually. After solidification, metal in the transition zone retained the original melt morphology, resulting in a decrease in the height of the tail of the deposition layer.

Comprehensive Analysis of lncRNA-mRNA Expression Profiles in Depression-like Responses of Mice Related to Polystyrene Nanoparticle Exposure.

Plastics in the environment can break down into nanoplastics (NPs), which pose a potential threat to public health. Studies have shown that the nervous system constitutes a significant target for nanoplastics. However, the potential mechanism behind nanoplastics' neurotoxicity remains unknown. This study aimed to investigate the role of lncRNA in the depressive-like responses induced by exposure to 25 nm polystyrene nanoplastics (PS NPs). Forty mice were divided into four groups administered doses of 0, 10, 25, and 50 mg/kg via gavage for 6 months. After conducting behavioral tests, RNA sequencing was used to detect changes in mRNAs, miRNAs, and lncRNAs in the prefrontal cortex of the mice in the 0 and 50 mg/kg PS NPs groups. The results revealed that mice exposed to chronic PS NPs developed depressive-like responses in a dose-dependent manner. It was demonstrated that 987 mRNAs, 29 miRNAs, and 116 lncRNAs were significantly different between the two groups. Then, a competing endogenous RNA (ceRNA) network containing 6 lncRNAs, 18 miRNAs, and 750 mRNAs was constructed. Enrichment results suggested that PS NPs may contribute to the onset of depression-like responses through the activation of axon guidance, neurotrophin-signaling pathways, and dopaminergic synapses. This study provided evidence of the molecular relationship between PS NPs and depression-like responses.

Exploring the role of m6A modification in the great obstetrical syndromes.

BACKGROUND: N6-methyladenosine (m6A) is one of the predominant RNA epigenetic modifications that modify RNAs reversibly and dynamically by "writers" (methyltransferase), "erasers" (demethylase), and "readers." OBJECTIVE: This review aimed to provide a comprehensive understanding of the complexity of m6A regulation in the great obstetrical syndromes to understand its pathogenesis and potential therapeutic targets. METHODS: The terms "placenta or trophoblast" and "m6A or N6-methyladenosine" were searched in PubMed databases (June 2023). RESULTS: In this review, we discuss the regulatory role of m6A in the great obstetrical syndromes such as preeclampsia (PE), spontaneous abortion (SA), hyperglycemia in pregnancy (HIP) and fetal growth to emphasize the clinical relevance of m6A dysregulation in pregnancy. We also describe mechanisms that potentially involve the participation of m6A methylation, such as proliferation, invasion, migration, apoptosis, autophagy, endoplasmic reticulum stress, macrophage polarization, and inflammation. CONCLUSION: We summarize the recent research progress on the role of m6A modification in the great obstetrical syndromes and placental function and provide a brief perspective on its prospective applications.

Linear epitopes on the capsid protein of norovirus commonly elicit high antibody response among past-infected individuals.

BACKGROUND: Human norovirus (HuNoV) is the leading cause of acute nonbacterial gastroenteritis globally, and its infection is usually self-limited, so most people become past Norovirus (NoV)-infected individuals. It is known that some antibody responses may play a critical role in preventing viral infection and alleviating disease; however, the characteristics and functions of particular antibody responses in persons with previous infections are not fully understood. Capsid proteins, including VP1 and VP2, are crucial antigenic components of NoV and may regulate antibody immune responses, while epitope-specific antibody responses to capsid proteins have not been comprehensively characterized. METHODS: We prepared purified VP1 and VP2 proteins by ion exchange chromatography and measured serum antigen-specific IgG levels in 398 individuals by ELISA. Overlapping 18-mer peptides covering the full length of VP1 and VP2 were synthesized, and then we identified linear antigenic epitopes from 20 subjects with strong IgG positivity. Subsequently, specific antibody responses to these epitopes were validated in 185 past infected individuals, and the conservation of epitopes was analyzed. Finally, we obtained epitope-specific antiserum by immunizing mice and expressed virus-like particles (VLPs) in an insect expression system for a blockade antibody assay to evaluate the receptor-blocking ability of epitope-specific antibodies. RESULTS: The IgG responses of VP1 were significantly stronger than those of VP2, both of which had high positive rates of over 80%. The overall positive rate of VP1-IgG and/or VP2-IgG was approximately 94%, which may be past NoV-infected individuals. Four linear antigenic B-cell epitopes of capsid proteins were identified, namely, VP1199-216, VP1469-492, VP297-120, and VP2241-264, all of which were conserved. The IgG response rates of the above epitopes in past NoV-infected individuals were 38.92%, 22.16%, 8.11% and 28.11%, respectively. In addition, VP1199-216- and VP1469-492-specific antibodies can partially block the binding of VLPs to the receptor histo-blood group antigen (HBGA). CONCLUSION: This is the first study to describe specific antibody responses of VP2 and to identify its B-cell epitopes. Our findings offer data for a more thorough understanding of norovirus capsid protein-specific IgG responses and could provide useful information for designing and developing vaccines.

Site-specific Atg13 methylation-mediated autophagy regulates epithelial inflammation in PM2.5-induced pulmonary fibrosis.

Fine particulate matters (PM2.5) increased the risk of pulmonary fibrosis. However, the regulatory mechanisms of lung epithelium in pulmonary fibrosis remained elusive. Here we developed PM2.5-exposure lung epithelial cells and mice models to investigate the role of autophagy in lung epithelia mediating inflammation and pulmonary fibrosis. PM2.5 exposure induced autophagy in lung epithelial cells and then drove pulmonary fibrosis by activation of NF-κB/NLRP3 signaling pathway. PM2.5-downregulated ALKBH5 protein expression promotes m6A modification of Atg13 mRNA at site 767 in lung epithelial cells. Atg13-mediated ULK complex positively regulated autophagy and inflammation in epithelial cells with PM2.5 treatment. Knockout of ALKBH5 in mice further accelerated ULK complex-regulated autophagy, inflammation and pulmonary fibrosis. Thus, our results highlighted that site-specific m6A methylation on Atg13 mRNA regulated epithelial inflammation-driven pulmonary fibrosis in an autophagy-dependent manner upon PM2.5 exposure, and it provided target intervention strategies towards PM2.5-induced pulmonary fibrosis.

Immunodominant SARS-CoV-2-specific CD4+ and CD8+ T-cell responses elicited by inactivated vaccines in healthy adults.

Safety profiles and humoral responses to inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines have been previously assessed, but cellular immune responses to inactivated SARS-CoV-2 vaccines remain understudied. Here, we report the comprehensive characteristics of SARS-CoV-2-specific CD4+ and CD8+ T-cell responses elicited by the BBIBP-CorV vaccine. A total of 295 healthy adults were recruited, and SARS-CoV-2-specific T-cell responses were detected after stimulation with overlapping peptide pools spanning the entire length of the envelope (E), membrane (M), nucleocapsid (N), and spike (S) proteins. Robust and durable CD4+ (p < 0.0001) and CD8+ (p < 0.0001) T-cell responses specific to SARS-CoV-2 were detected following the third vaccination, with an increase in specific CD8+ T-cells, compared to CD4+ T-cells. Cytokine profiles showed that interferon gamma and tumor necrosis factor-α were predominantly expressed with the negligible expression of interleukin (IL)-4 and IL-10, indicating a Th1- or Tc1-biased response. Compared to E and M proteins, N and S activated a higher proportion of specific T-cells with broader functions. The predominant frequency of the N antigen (49/89) was highest for CD4+ T-cell immunity. Furthermore, N19-36 and N391-408 were identified to contain dominant CD8+ and CD4+ T-cell epitopes, respectively. In addition, N19-36 -specific CD8+ T-cells were mainly effector memory CD45RA cells, whereas N391-408 -specific CD4+ T-cells were mainly effector memory cells. Therefore, this study reports comprehensive features of T-cell immunity induced by the inactivated SARS-CoV-2 vaccine BBIBP-CorV and proposes highly conserved candidate peptides which may be beneficial in vaccine optimization.

Detailed curriculum vitae of HER2-targeted therapy.

With the booming development of precision medicine, molecular targeted therapy has been widely used in clinical oncology treatment due to a smaller number of side effects and its superior accuracy compared to that of traditional strategies. Among them, human epidermal growth factor receptor 2 (HER2)-targeted therapy has attracted considerable attention and has been used in the clinical treatment of breast and gastric cancer. Despite excellent clinical effects, HER2-targeted therapy remains in its infancy due to its resulting inherent and acquired resistance. Here, a comprehensive overview of HER2 in numerous cancers is presented, including its biological role, involved signaling pathways, and the status of HER2-targeted therapy.

Enhancing Conformational Sampling for Intrinsically Disordered and Ordered Proteins by Variational Autoencoder.

Intrinsically disordered proteins (IDPs) account for more than 50% of the human proteome and are closely associated with tumors, cardiovascular diseases, and neurodegeneration, which have no fixed three-dimensional structure under physiological conditions. Due to the characteristic of conformational diversity, conventional experimental methods of structural biology, such as NMR, X-ray diffraction, and CryoEM, are unable to capture conformational ensembles. Molecular dynamics (MD) simulation can sample the dynamic conformations at the atomic level, which has become an effective method for studying the structure and function of IDPs. However, the high computational cost prevents MD simulations from being widely used for IDPs conformational sampling. In recent years, significant progress has been made in artificial intelligence, which makes it possible to solve the conformational reconstruction problem of IDP with fewer computational resources. Here, based on short MD simulations of different IDPs systems, we use variational autoencoders (VAEs) to achieve the generative reconstruction of IDPs structures and include a wider range of sampled conformations from longer simulations. Compared with the generative autoencoder (AEs), VAEs add an inference layer between the encoder and decoder in the latent space, which can cover the conformational landscape of IDPs more comprehensively and achieve the effect of enhanced sampling. Through experimental verification, the Cα RMSD between VAE-generated and MD simulation sampling conformations in the 5 IDPs test systems was significantly lower than that of AE. The Spearman correlation coefficient on the structure was higher than that of AE. VAE can also achieve excellent performance regarding structured proteins. In summary, VAEs can be used to effectively sample protein structures.

N6-methyladenosine mediates Nrf2 protein expression involved in PM2.5-induced pulmonary fibrosis.

It has been reported that particulate matter with an aerodynamic diameter of <2.5 µm (PM2.5) could induce epithelial-mesenchymal transition (EMT)- and extracellular matrix (ECM)-related pulmonary fibrosis (PF). The transcription factor Nrf2 alleviated PM2.5-induced PF by antagonizing oxidative stress. The N6-methyladenosine (m6A) modification plays a significant role in the stress response. However, the effect of m6A modification on the mechanisms of Nrf2-mediated defense against PM2.5-induced PF remained unknown. Here, we explored the role and the underlying molecular mechanisms of m6A methylation of Nrf2 mRNA in PM2.5-induced PF. We established filtered air (FA), unfiltered air (UA), and concentrated PM2.5 air (CA) group mice model and 0, 50, and 100 µg/mL PM2.5-treated 16HBE cell models. The extent of lung fibrosis in mice and fibrosis indicators were detected by histopathological analysis, immunohistochemical staining and western blotting. The molecular mechanism of m6A-modified Nrf2 was demonstrated by m6A-methylated RNA immunoprecipitation (MeRIP), RNA immunoprecipitation (RIP), qRT-PCR and T3 ligase-based PCR. Our data showed that PM2.5 exposure for 16 weeks could induce pulmonary fibrosis and activate Nrf2 signaling pathway. m6A methyltransferase METTL3 was upregulated after PM2.5 treatment in vivo and in vitro. Moreover, METTL3 mediated m6A modification of Nrf2 mRNA and promoted Nrf2 translation in mice and 16HBE cells after PM2.5 exposure. Mechanistically, three m6A-modified sites (1317, 1376 and 935; numbered relative to the first nucleotide of 3'UTR) of Nrf2 mRNA were identified in PM2.5-treatment 16HBE cells. Furthermore, the m6A binding proteins YTHDF1/IGF2BP1 promoted Nrf2 translation by binding to m6A residues of Nrf2 mRNA. Our results revealed the mechanism of m6A mediated Nrf2 signaling pathway against oxidative stress, which affected the development of PM2.5-induced PF.

Insulin Autoimmune Syndrome: A Systematic Review.

Insulin autoimmune syndrome (IAS) is a rare endocrine disorder characterized by recurrent episodes of severe hypoglycemia, markedly elevated serum insulin, and positive insulin autoantibodies. In recent years, various countries have reported it one after another. It can be seen that we must pay attention to this disease. The diagnosis of IAS is challenging, requiring a careful workup aimed at excluding other causes of hyperinsulinemic hypoglycemia. High levels of insulin autoantibodies are found in patients, and C-peptide is not parallel to insulin, which could be diagnostic. IAS is a self-limiting disease with a good prognosis. Its treatment mainly includes symptomatic supportive treatment, such as adjusting the diet and using acarbose and other drugs to delay the absorption of glucose to prevent hypoglycemia. For patients with severe symptoms, available treatments may include drugs that reduce pancreatic insulin secretion (such as somatostatin and diazoxide), immunosuppressants (glucocorticoids, zaprin, and rituximab), and even plasma exchange to remove autoantibodies from the body. This review provides a comprehensive analysis of the epidemiology, pathogenesis, clinical manifestations, diagnosis and identification, and monitoring and treatment management of IAS.

UreB immunodominant epitope-specific CD8+ T-cell responses were beneficial in reducing gastric symptoms in Helicobacter pylori-infected individuals.

BACKGROUND AND AIMS: Although Helicobacter pylori is recognized as an extracellular infection bacterium, it can lead to an increase in the number of CD8+ T cells after infection. At present, the characteristics of H. pylori antigen-specific CD8+ T cells and the epitope response have not been elucidated. This study was focused on putative protective antigen UreB to detect specific CD8+ T-cell responses in vitro and screen for predominant response epitopes. METHODS: The PBMCs collected from H. pylori-infected individuals were stimulated by UreB peptide pools in vitro to identify the immunodominant CD8+ T-cell epitopes. Furthermore, their HLA restriction characteristics were detected accordingly by NGS. Finally, the relationship between immunodominant responses and appearance of gastric symptoms after H. pylori infection was conducted. RESULTS: UreB-specific CD8+ T-cell responses were detected in H. pylori-infected individuals. Three of UreB dominant epitopes (A-2 (UreB443-451 : GVKPNMIIK), B-4 (UreB420-428 : SEYVGSVEV), and C-1 (UreB5-13 : SRKEYVSMY)) were firstly identified and mainly presented by HLA-A*1101, HLA-B*4001 and HLA-C*0702 alleles, respectively. C-1 responses were mostly occurred in H. pylori-infected subjects without gastric symptoms and may alleviate the degree of gastric inflammation. CONCLUSIONS: The UreB dominant epitope-specific CD8+ T-cell response was closely related to the gastric symptoms after H. pylori infection, and the C-1 (UreB5-13 ) dominant peptides may be protective epitopes.

Mechanism of YY1 mediating autophagy dependent ferroptosis in PM2.5 induced cardiac fibrosis.

Epidemiological studies have demonstrated strong associations between exposure to ambient fine particulate matter (PM2.5) and cardiac disease. To investigate the potential mechanism of cardiac fibrosis induced by PM2.5, we established PM2.5 exposure models in vivo and in vitro, and then cardiac fibrosis was evaluated. The ferroptosis and ferritinophagy was detected to characterize the effects of PM2.5 exposure. The results indicated that PM2.5 exposure could induce cardiac fibrosis in mice. YY1 was induced by PM2.5 exposure and then increased NCOA4, a cargo receptor for ferritinophagy, which interacted with FHC and promoted the transport of ferritin to the autophagosome for degradation. The release of large amounts of free iron from ferritinophagy led to lipid peroxidation directly via the Fenton reaction, thereby triggering ferroptosis. Moreover, siNCOA4 could partly restore the FHC protein level in HL-1 cells and inhibit the occurrence of downstream ferroptosis. Functionally, NCOA4 knockdown inhibited ferroptosis and alleviated HL-1 cell death induced by PM2.5. Ferroptosis inhibitor (Ferrostatin-1) could reverse the promoting effect of ferritinophagy mediated ferroptosis on cardiac fibrosis induced by PM2.5 exposure in mice. Our study indicated that PM2.5 induced cardiac fibrosis through YY1 regulating ferritinophagy-dependent ferroptosis.