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Immunobiology May 2024Kangfuxin has been widely recognized for its use in treating ulcerative conditions and mucositis, primarily due to its anti-inflammatory properties, which promote cell...
Kangfuxin has been widely recognized for its use in treating ulcerative conditions and mucositis, primarily due to its anti-inflammatory properties, which promote cell proliferation, granulation tissue growth, and angiogenesis. However, the exact mechanisms underlying these effects remain poorly understood. In this study, we employed high-throughput mass spectrometry to identify 11 compounds in Kangfuxin, including uracil, hypoxanthine, xanthine, inosine, glutamic acid, glycine, alanine, valine, isoleucine, leucine, and lysine. Notably, the antipyretic and anti-inflammatory properties of inosine, one of these compounds, have not been well characterized. To address this gap, we induced fever in vivo using lipopolysaccharide (LPS) and conducted various experiments, including the analysis of endogenous mediators, inflammatory factors, quantitative polymerase chain reaction (QPCR), Western blotting, and hematoxylin and eosin (HE) staining. Our findings indicate that inosine significantly reduces LPS-induced fever, inhibits the expression of inflammatory factors, and alleviates the inflammatory response. These results suggest that inosine may serve as a potential therapeutic target for inflammatory diseases.
Topics: Inosine; Animals; Mice; Lipopolysaccharides; Anti-Inflammatory Agents; Antipyretics; Male; Inflammation; Fever; Disease Models, Animal; Inflammation Mediators; Cytokines; Drugs, Chinese Herbal
PubMed: 38781756
DOI: 10.1016/j.imbio.2024.152812 -
Cellular and Molecular Life Sciences :... May 2024RNA modifications are essential for the establishment of cellular identity. Although increasing evidence indicates that RNA modifications regulate the innate immune...
RNA modifications are essential for the establishment of cellular identity. Although increasing evidence indicates that RNA modifications regulate the innate immune response, their role in monocyte-to-macrophage differentiation and polarisation is unclear. While mA has been widely studied, other RNA modifications, including 5 hmC, remain poorly characterised. We profiled mA and 5 hmC epitranscriptomes, transcriptomes, translatomes and proteomes of monocytes and macrophages at rest and pro- and anti-inflammatory states. Transcriptome-wide mapping of mA and 5 hmC reveals enrichment of mA and/or 5 hmC on specific categories of transcripts essential for macrophage differentiation. Our analyses indicate that mA and 5 hmC modifications are present in transcripts with critical functions in pro- and anti-inflammatory macrophages. Notably, we also discover the co-occurrence of mA and 5 hmC on alternatively-spliced isoforms and/or opposing ends of the untranslated regions (UTR) of mRNAs with key roles in macrophage biology. In specific examples, RNA 5 hmC controls the decay of transcripts independently of mA. This study provides (i) a comprehensive dataset to interrogate the role of RNA modifications in a plastic system (ii) a resource for exploring different layers of gene expression regulation in the context of human monocyte-to-macrophage differentiation and polarisation, (iii) new insights into RNA modifications as central regulators of effector cells in innate immunity.
Topics: Macrophages; Cell Differentiation; Humans; Monocytes; Transcriptome; Gene Expression Regulation; RNA Processing, Post-Transcriptional; RNA, Messenger; Cell Polarity; RNA; Adenosine
PubMed: 38780787
DOI: 10.1007/s00018-024-05261-9 -
Clinical and Applied... 2024Ticagrelor is an antiplatelet drug, and its use increases the risk of bleeding. Coronary artery disease is significantly influenced by the widespread occurrence of...
PURPOSE
Ticagrelor is an antiplatelet drug, and its use increases the risk of bleeding. Coronary artery disease is significantly influenced by the widespread occurrence of diabetes mellitus. In order to decrease the incidence of clinical adverse events, a novel bleeding and thrombosis score is developed in this research.
METHODS
We conducted a retrospective analysis of patient data from two medical centers who were diagnosed with diabetes mellitus and treated with ticagrelor. We gathered information on every patient from the electronic database of the hospital and follow-up. The collected data were statistically analyzed to obtain risk factors for bleeding and ischemic events.
RESULTS
A total of 851 patients with diabetes mellitus who have been administered ticagrelor are included in our investigation. A total of 76 patients have bleeding events and 80 patients have ischemic events. The analysis of multiple variables indicates that characteristics like the age of >65, having a previous occurrence of bleeding, experiencing anemia, using aspirin, and taking atorvastatin are linked to a higher likelihood of bleeding. Additionally, the age of >65, smoking, having a history of blood clots, and having a BMI ≥ 30 are found to increase the risk of ischemia.
CONCLUSION
The AB score established in this study was better than the HAS-BLED score,and the same is true for the ABST score to the CHADS-VASc score. This new risk assessment model can potentially detect patients who are at high risk for bleeding and ischemic events. For high-risk patients, the dose of ticagrelor can be adjusted appropriately or the medication can be adjusted.(2023-09-11, ChiCTR2300075627).
Topics: Humans; Ticagrelor; Female; Male; Hemorrhage; Aged; Retrospective Studies; Middle Aged; Diabetes Mellitus; Platelet Aggregation Inhibitors; Risk Factors; Ischemia; Thrombosis
PubMed: 38780348
DOI: 10.1177/10760296241254107 -
BMC Medical Genomics May 2024Head and neck squamous cell carcinoma (HNSCC) is a prevalent cancer with a poor survival rate due to anatomical limitations of the head and a lack of reliable...
BACKGROUND
Head and neck squamous cell carcinoma (HNSCC) is a prevalent cancer with a poor survival rate due to anatomical limitations of the head and a lack of reliable biomarkers. Cuproptosis represents a novel cellular regulated death pathway, and N6-methyladenosine (m6A) is the most common internal RNA modification in mRNA. They are intricately connected to tumor formation, progression, and prognosis. This study aimed to construct a risk model for HNSCC using a set of mRNAs associated with m6A regulators and cuproptosis genes (mcrmRNA).
METHODS
RNA-seq and clinical data of HNSCC patients from The Cancer Genome Atlas (TCGA) database were analyzed to develop a risk model through the least absolute shrinkage and selection operator (LASSO) analysis. Survival analysis and receiver operating characteristic (ROC) analysis were performed for the high- and low-risk groups. Additionally, the model was validated using the GSE41613 dataset from the Gene Expression Omnibus (GEO) database. GSEA and CIBERSORT were applied to investigate the immune microenvironment of HNSCC.
RESULTS
A risk model consisting of 32 mcrmRNA was developed using the LASSO analysis. The risk score of patients was confirmed to be an independent prognostic indicator by multivariate Cox analysis. The high-risk group exhibited a higher tumor mutation burden. Additionally, CIBERSORT analysis indicated varying levels of immune cell infiltration between the two groups. Significant disparities in drug sensitivity to common medications were also observed. Enrichment analysis further unveiled significant differences in metabolic pathways and RNA processing between the two groups.
CONCLUSIONS
Our risk model can predict outcomes for HNSCC patients and offers valuable insights for personalized therapeutic approaches.
Topics: Humans; Squamous Cell Carcinoma of Head and Neck; Head and Neck Neoplasms; Adenosine; Male; RNA, Messenger; Prognosis; Female; Biomarkers, Tumor; Risk Assessment; Gene Expression Regulation, Neoplastic; Middle Aged; Tumor Microenvironment
PubMed: 38778403
DOI: 10.1186/s12920-024-01916-5 -
Current Opinion in Genetics &... Jun 2024N-methyladenosine (mA) is the most prevalent internal RNA modification in eukaryotic messenger RNAs (mRNAs), regulating gene expression at the transcription and... (Review)
Review
N-methyladenosine (mA) is the most prevalent internal RNA modification in eukaryotic messenger RNAs (mRNAs), regulating gene expression at the transcription and post-transcription levels. Complex interplay between mA and other well-studied epigenetic modifications, including histone modifications and DNA modification, has been extensively reported in recent years. The crosstalk between RNA mA modification and histone/DNA modifications plays a critical role in establishing the chromatin state for the precise and specific fine-tuning of gene expression and undoubtedly has profound impacts on both physiological and pathological processes. In this review, we discuss the crosstalk between RNA mA modification and histone/DNA modifications, emphasizing their sophisticated communications and the mechanisms underlying to gain a comprehensive view of the biological relevance of mA-based epigenetic network.
Topics: Adenosine; Chromatin; DNA; DNA Methylation; Epigenesis, Genetic; Histones; RNA; RNA, Messenger
PubMed: 38776766
DOI: 10.1016/j.gde.2024.102205 -
International Journal of Medical... 2024Inflammatory responses, apoptosis, and oxidative stress, are key factors that contribute to hepatic ischemia/reperfusion (I/R) injury, which may lead to the failure of...
Inflammatory responses, apoptosis, and oxidative stress, are key factors that contribute to hepatic ischemia/reperfusion (I/R) injury, which may lead to the failure of liver surgeries, such as hepatectomy and liver transplantation. The N6-methyladenosine (mA) modification has been implicated in multiple biological processes, and its specific role and mechanism in hepatic I/R injury require further investigation. Dot blotting analysis was used to profile mA levels in liver tissues at different reperfusion time points in hepatic I/R mouse models. Hepatocyte-specific METTL3 knockdown (HKD) mice were used to determine the function of METTL3 during hepatic I/R. RNA sequencing and western blotting were performed to assess the potential signaling pathways involved with the deficiency of METTL3. Finally, AAV8-TBG-METTL3 was injected through the tail vein to further elucidate the role of METTL3 in hepatic I/R injury. The mA modification levels and the expression of METTL3 were upregulated in mouse livers during hepatic I/R injury. METTL3 deficiency led to an exacerbated inflammatory response and increased cell death during hepatic I/R, whereas overexpression of METTL3 reduced the extent of liver injury. Bioinformatic analysis revealed that the MAPK pathway was significantly enriched in the livers of METTL3-deficient mice. METTL3 protected the liver from I/R injury, possibly by inhibiting the phosphorylation of JNK and ERK, but not P38. METTL3 deficiency aggravates hepatic I/R injury in mice by activating the MAPK signaling pathway. METTL3 may be a potential therapeutic target in hepatic I/R injury.
Topics: Animals; Humans; Male; Mice; Adenosine; Apoptosis; Disease Models, Animal; Hepatocytes; Liver; MAP Kinase Signaling System; Methyltransferases; Mice, Inbred C57BL; Mice, Knockout; Reperfusion Injury; HEK293 Cells
PubMed: 38774758
DOI: 10.7150/ijms.94177 -
Molecular Medicine (Cambridge, Mass.) May 2024Catalpol (CAT) has various pharmacological activities and plays a protective role in cerebral ischemia. It has been reported that CAT played a protective role in...
OBJECTIVE
Catalpol (CAT) has various pharmacological activities and plays a protective role in cerebral ischemia. It has been reported that CAT played a protective role in cerebral ischemia by upregulaing NRF1 expression. Bioinformatics analysis reveals that NRF1 can be used as a transcription factor to bind to the histone acetyltransferase KAT2A. However, the role of KAT2A in cerebral ischemia remains to be studied. Therefore, we aimed to investigate the role of CAT in cerebral ischemia and its related mechanism.
METHODS
In vitro, a cell model of oxygen and glucose deprivation/reperfusion (OGD/R) was constructed, followed by evaluation of neuronal injury and the expression of METTL3, Beclin-1, NRF1, and KAT2A. In vivo, a MCAO rat model was prepared by means of focal cerebral ischemia, followed by assessment of neurological deficit and brain injury in MCAO rats. Neuronal autophagy was evaluated by observation of autophagosomes in neurons or brain tissues by TEM and detection of the expression of LC3 and p62.
RESULTS
In vivo, CAT reduced the neurological function deficit and infarct volume, inhibited neuronal apoptosis in the cerebral cortex, and significantly improved neuronal injury and excessive autophagy in MCAO rats. In vitro, CAT restored OGD/R-inhibited cell viability, inhibited cell apoptosis, LDH release, and neuronal autophagy. Mechanistically, CAT upregulated NRF1, NRF1 activated METTL3 via KAT2A transcription, and METTL3 inhibited Beclin-1 via mA modification.
CONCLUSION
CAT activated the NRF1/KAT2A/METTL3 axis and downregulated Beclin-1 expression, thus relieving neuronal injury and excessive autophagy after cerebral ischemia.
Topics: Animals; Autophagy; Beclin-1; Rats; Neurons; Brain Ischemia; Male; Iridoid Glucosides; Neuroprotective Agents; Disease Models, Animal; Apoptosis; Rats, Sprague-Dawley; Reperfusion Injury; Adenosine
PubMed: 38773376
DOI: 10.1186/s10020-024-00818-7 -
Nature Communications May 2024Epigenetic mechanisms bridge genetic and environmental factors that contribute to the pathogenesis of major depression disorder (MDD). However, the cellular specificity...
Epigenetic mechanisms bridge genetic and environmental factors that contribute to the pathogenesis of major depression disorder (MDD). However, the cellular specificity and sensitivity of environmental stress on brain epitranscriptomics and its impact on depression remain unclear. Here, we found that ALKBH5, an RNA demethylase of N6-methyladenosine (m6A), was increased in MDD patients' blood and depression models. ALKBH5 in astrocytes was more sensitive to stress than that in neurons and endothelial cells. Selective deletion of ALKBH5 in astrocytes, but not in neurons and endothelial cells, produced antidepressant-like behaviors. Astrocytic ALKBH5 in the mPFC regulated depression-related behaviors bidirectionally. Meanwhile, ALKBH5 modulated glutamate transporter-1 (GLT-1) m6A modification and increased the expression of GLT-1 in astrocytes. ALKBH5 astrocyte-specific knockout preserved stress-induced disruption of glutamatergic synaptic transmission, neuronal atrophy and defective Ca activity. Moreover, enhanced m6A modification with S-adenosylmethionine (SAMe) produced antidepressant-like effects. Our findings indicate that astrocytic epitranscriptomics contribute to depressive-like behaviors and that astrocytic ALKBH5 may be a therapeutic target for depression.
Topics: Animals; Astrocytes; AlkB Homolog 5, RNA Demethylase; Mice; Humans; Depressive Disorder, Major; Male; Mice, Knockout; Female; Disease Models, Animal; Mice, Inbred C57BL; Neurons; Stress, Psychological; Adenosine; Excitatory Amino Acid Transporter 2; Behavior, Animal; Prefrontal Cortex; Depression; Adult; Synaptic Transmission; Middle Aged
PubMed: 38773146
DOI: 10.1038/s41467-024-48730-2 -
Nature Communications May 2024Hypomyelinating leukodystrophy (HLD) is an autosomal recessive disorder characterized by defective central nervous system myelination. Exome sequencing of two siblings...
Hypomyelinating leukodystrophy (HLD) is an autosomal recessive disorder characterized by defective central nervous system myelination. Exome sequencing of two siblings with severe cognitive and motor impairment and progressive hypomyelination characteristic of HLD revealed homozygosity for a missense single-nucleotide variant (SNV) in EPRS1 (c.4444 C > A; p.Pro1482Thr), encoding glutamyl-prolyl-tRNA synthetase, consistent with HLD15. Patient lymphoblastoid cell lines express markedly reduced EPRS1 protein due to dual defects in nuclear export and cytoplasmic translation of variant EPRS1 mRNA. Variant mRNA exhibits reduced METTL3 methyltransferase-mediated writing of N-methyladenosine (mA) and reduced reading by YTHDC1 and YTHDF1/3 required for efficient mRNA nuclear export and translation, respectively. In contrast to current models, the variant does not alter the sequence of mA target sites, but instead reduces their accessibility for modification. The defect was rescued by antisense morpholinos predicted to expose mA sites on target EPRS1 mRNA, or by mA modification of the mRNA by METTL3-dCas13b, a targeted RNA methylation editor. Our bioinformatic analysis predicts widespread occurrence of SNVs associated with human health and disease that similarly alter accessibility of distal mRNA mA sites. These results reveal a new RNA-dependent etiologic mechanism by which SNVs can influence gene expression and disease, consequently generating opportunities for personalized, RNA-based therapeutics targeting these disorders.
Topics: Female; Humans; Male; Adenosine; Hereditary Central Nervous System Demyelinating Diseases; Homozygote; Methyltransferases; Mutation, Missense; Nerve Tissue Proteins; RNA Splicing Factors; RNA, Messenger; RNA-Binding Proteins
PubMed: 38769304
DOI: 10.1038/s41467-024-48549-x -
Cell Death & Disease May 2024Osteosarcoma is a malignant bone tumor that primarily inflicts the youth. It often metastasizes to the lungs after chemotherapy failure, which eventually shortens...
Osteosarcoma is a malignant bone tumor that primarily inflicts the youth. It often metastasizes to the lungs after chemotherapy failure, which eventually shortens patients' lives. Thus, there is a dire clinical need to develop a novel therapy to tackle osteosarcoma metastasis. Methionine dependence is a special metabolic characteristic of most malignant tumor cells that may offer a target pathway for such therapy. Herein, we demonstrated that methionine deficiency restricted the growth and metastasis of cultured human osteosarcoma cells. A genetically engineered Salmonella, SGN1, capable of overexpressing an L-methioninase and hydrolyzing methionine led to significant reduction of methionine and S-adenosyl-methionine (SAM) specifically in tumor tissues, drastically restricted the growth and metastasis in subcutaneous xenograft, orthotopic, and tail vein-injected metastatic models, and prolonged the survival of the model animals. SGN1 also sharply suppressed the growth of patient-derived organoid and xenograft. Methionine restriction in the osteosarcoma cells initiated severe mitochondrial dysfunction, as evident in the dysregulated gene expression of respiratory chains, increased mitochondrial ROS generation, reduced ATP production, decreased basal and maximum respiration, and damaged mitochondrial membrane potential. Transcriptomic and molecular analysis revealed the reduction of C1orf112 expression as a primary mechanism underlies methionine deprivation-initiated suppression on the growth and metastasis as well as mitochondrial functions. Collectively, our findings unraveled a molecular linkage between methionine restriction, mitochondrial function, and osteosarcoma growth and metastasis. A pharmacological agent, such as SGN1, that can achieve tumor specific deprivation of methionine may represent a promising modality against the metastasis of osteosarcoma and potentially other types of sarcomas as well.
Topics: Osteosarcoma; Methionine; Humans; Animals; Mitochondria; Cell Line, Tumor; Mice; Bone Neoplasms; Cell Proliferation; Neoplasm Metastasis; S-Adenosylmethionine; Mice, Nude; Reactive Oxygen Species; Gene Expression Regulation, Neoplastic
PubMed: 38769167
DOI: 10.1038/s41419-024-06727-1