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1.
Biochim Biophys Acta Mol Cell Res ; 1870(1): 119380, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36228837

RESUMO

The existence of N6-adenosine methylation (m6A) of mRNA has been known for a long time, but only recently its regulatory potential was uncovered. Current research deciphers the molecular determinants leading to the deposition of this modification and consequences for modified mRNAs. It also evaluates the importance of such modifications for specific cell types and programs. In this review, we summarize the current knowledge on m6A modification of mRNAs in conventional and regulatory T cells and T-cell-driven immune responses and pathology. We discuss the impact of m6A modification on T cell activation including cytokine and antigen receptor signaling or sensing of double-stranded RNAs (dsRNA).


Assuntos
Adenosina , Linfócitos T , Metilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Adenosina/genética , Linfócitos T/metabolismo
2.
Ann Lab Med ; 43(2): 153-166, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36281509

RESUMO

Background: Despite the popularity of the NeoBase 2 Non-derivatized MSMS assay (PerkinElmer, Turku, Finland), there are no reports of its comprehensive evaluation, including the ability to distinguish transient tyrosinemia of the newborn (TTN) from tyrosinemia type 1 (TYR 1) using succinylacetone (SUAC). No newborn screening (NBS) cutoffs for preterm neonates in the Korean population have been suggested. We evaluated the NeoBase 2 assay and identified analytes requiring different cutoffs in preterm neonates. Methods: Residual NBS dried blood spot samples and proficiency testing (PT) materials of the Newborn Screening Quality Assurance Program and the Korean Association of External Quality Assessment Service were used. Precision, accuracy, limit of detection (LOD), lower limit of quantification (LLOQ), linearity, recovery, carryover, and performance of SUAC were evaluated. Cutoffs were determined, and analytes requiring different cutoffs in preterm neonates were investigated. Results: Mean CVs for within-run and between-day precision were within 15%. Accuracy analysis indicated high agreement with in-house derivatized assay results and results of other PT participants. All analytes demonstrated acceptable LOD, LLOQ, and linearity. Recoveries were acceptable, except for SUAC. Carryover was negligible. Cutoffs were established for all analytes; Tyr, adenosine, and C20:0-lysophosphatidylcholine required different cutoffs in preterm neonates. Differential diagnosis of TYR 1 and TTN was successful with simultaneous Tyr and SUAC measurement. Conclusions: The NeoBase 2 assay demonstrated satisfactory performance. The additional analytes provide a wider diagnostic coverage, and the simultaneous measurement of Tyr and SUAC is efficient in excluding TYR 1. The new cutoffs for preterm neonates may decrease false-positive rates, without compromising diagnostic sensitivity.


Assuntos
Espectrometria de Massas em Tandem , Tirosinemias , Humanos , Recém-Nascido , Lisofosfatidilcolinas , Tirosinemias/diagnóstico , Triagem Neonatal/métodos , Adenosina
3.
Neuropharmacology ; 222: 109306, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36341808

RESUMO

Prolonged exposure (PE) therapy aiming to promote fear extinction is a useful treatment for post-traumatic stress disorder (PTSD). However, the mechanisms underlying fear extinction and effective methods used to promote fear extinction in PTSD are still lacking. In this study, we displayed dysfunctions of cyclic adenosine 3,5-monophosphate (cAMP)-protein kinase A (PKA), protein kinase B (Akt)/mammalian target of rapamycin (mTOR) and calcium signaling in peripheral serum of PTSD patients using bioinformatics analysis. Later, we confirmed the dysfunctions of cAMP-PKA, AKT/mTOR and calcium signaling in the hippocampus of PTSD mice. Moreover, the reduction of calpain1 in the hippocampus enhanced fear memory acquisition. Single activation of PKA by systemic application of rolipram (ROL) or meglumine cyclic adenylate (M-cAMP) before re-exposure promoted fear extinction and improved anxiety-like behavior in PTSD mice. Moreover, systemic application of ROL before re-exposure improved hippocampal brain-derived neurotrophic factor (BDNF)/tyrosine kinase receptor B (TrkB) signaling and calpain1/AKT/mTOR signaling. Interestingly, the effects of activation of PKA could be partially blocked by TrkB antagonist, ANA-12 and mTOR inhibitor, RAPA. Finally, intranasal administration of ROL could also adjust the abnormality of fear memory and improve anxiety-like behaviors in PTSD mice. Collectively, activation of PKA could promote fear extinction, which correlated with the reduction of anxiety-like behavior. The mechanisms were related to the BDNF/TrkB and calpain1/AKT/mTOR signaling pathways. PKA activation might be a useful complementary therapy for PE in the symptom elimination of PTSD.


Assuntos
Medo , Transtornos de Estresse Pós-Traumáticos , Camundongos , Animais , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Proteínas Quinases Dependentes de AMP Cíclico , Proteínas Proto-Oncogênicas c-akt , Fator Neurotrófico Derivado do Encéfalo , Extinção Psicológica , Ansiedade/tratamento farmacológico , Serina-Treonina Quinases TOR , Rolipram , Sinalização do Cálcio , Adenosina , Mamíferos
4.
Neuropharmacology ; 222: 109296, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36377091

RESUMO

Alcohol-related poisoning is the foremost cause of death resulting from excessive acute alcohol consumption. Respiratory failure is crucial to the pathophysiology of fatal alcohol poisoning. Alcohol increases accumulation of extracellular adenosine. Adenosine suppresses breathing. The goal of this investigation was to test the hypothesis that adenosine signaling contributes to alcohol-induced respiratory suppression. In the first experiment, the breathing of mice was monitored following an injection of the non-selective adenosine receptor antagonist caffeine (40 mg/kg), alcohol (5 g/kg), or alcohol and caffeine combined. Caffeine reduced alcohol-induced respiratory suppression suggesting that adenosine contributes to the effects of alcohol on breathing. The second experiment utilized the same experimental design, but with the blood brain barrier impermeant non-selective adenosine receptor antagonist 8-sulfophenyltheophylline (8-SPT, 60 mg/kg) instead of caffeine. 8-SPT did not reduce alcohol-induced respiratory suppression suggesting that adenosine is contributing to alcohol-induced respiratory suppression in the central nervous system. The third and fourth experiments used the same experimental design as the first, but with the selective A1 receptor antagonist DPCPX (1 mg/kg) and the selective A2A receptor antagonist istradefylline (3.3 mg/kg). Istradefylline, but not DPCPX, reduced alcohol-induced respiratory suppression indicating an A2A receptor mediated effect. In the fifth experiment, alcohol-induced respiratory suppression was evaluated in Adk+/- mice which have impaired adenosine metabolism. Alcohol-induced respiratory suppression was exacerbated in Adk+/- mice. These findings indicate that adenosinergic signaling contributes to alcohol-induced respiratory suppression. Improving our understanding of how alcohol affects breathing may lead to better treatment strategies and better outcomes for patients with severe alcohol poisoning.


Assuntos
Adenosina , Insuficiência Respiratória , Animais , Camundongos , Adenosina/farmacologia , Cafeína/farmacologia , Etanol , Sistema Respiratório , Antagonistas de Receptores Purinérgicos P1/farmacologia , Receptor A2A de Adenosina , Antagonistas do Receptor A2 de Adenosina/farmacologia , Xantinas/farmacologia , Receptor A1 de Adenosina
5.
Neuropharmacology ; 222: 109273, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36252615

RESUMO

The cost-benefit decision-making (CBDM) is critical to normal human activity and a diminished willingness to expend effort to obtain rewards is a prevalent/noted characteristic of neuropsychiatric disorders such as schizophrenia, Parkinson's disease. Numerous studies have identified nucleus accumbens (NAc) as an important locus for CBDM control but their neuromodulatory and behavioral mechanisms remain largely under-explored. Adenosine A2A receptors (A2ARs), which are highly concentrated in the striatopallidal neurons, can integrate glutamate and dopamine signals for controlling effort-related choice behaviors. While the involvement of A2ARs in effort-based decision making is well documented, the role of other decision variables (reward discrimination) in effort-based decision making and the role of A2AR in delay-based decision making are less clear. In this study, we have developed a well-controlled CBDM behavioral paradigm to manipulate effort/cost and reward independently or in combination, allowing a dissection of four behavioral elements: effort-based CBDM (E-CBDM), delay-based CBDM (D-CBDM), reward discrimination (RD), effort discrimination (ED), and determined the effect of genetic knockdown (KD) of NAc A2AR on the four behavioral elements. We found that A2AR KD in NAc increased the choice for larger, more costly reward in the E-CBDM, but not D-CBDM. Furthermore, this high-effort/high-reward bias was attributable to the increased willingness to engage in effort but not the effect of discrimination of reward magnitude. Our findings substantiate an important role of the NAc A2AR in control of E-CBDM and support that pharmacologically targeting NAc A2ARs would be a useful strategy for treating the aberrant effort-based decision making in neuropsychiatric disorders.


Assuntos
Adenosina , Receptor A2A de Adenosina , Humanos , Adenosina/farmacologia , Tomada de Decisões/fisiologia , Recompensa , Viés
6.
Int J Oncol ; 62(1)2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36382642

RESUMO

Oral cancer is one of the highly malignant tumors with poor prognosis. The pathogenic mechanisms of oral cancer have remained to be fully elucidated and this brings significant challenges to the treatment. RNA modification is a common intracellular chemical modification that has been related to various pathological processes, such as blood diseases, immune system diseases and cancer. As the most common and abundant RNA modification in eukaryotic mRNA, N6­methyladenosine (m6A) modification has a crucial role in several cancers, including oral cancer. m6A modification directly affects gene expression levels and regulates various physiological and pathological processes. It has been demonstrated that m6A modification may affect the proliferation, migration and invasion of oral cancer cells by regulating the level of m6A modification. In the present review, the effects of m6A modification on the proliferation and death of oral cancer cells, as well as the occurrence and development of oral cancer, were analyzed in order to provide a new target for treatment. Furthermore, the roles of m6A modification in chemotherapy resistance and potential immunotherapy were analyzed and new treatment ideas were provided.


Assuntos
Adenosina , Neoplasias Bucais , Humanos , Metilação , RNA Mensageiro/genética , Neoplasias Bucais/genética
7.
Mol Cancer ; 21(1): 32, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35090469

RESUMO

N6-methyladenosine (m6A) methylation, the most common form of internal RNA modification in eukaryotes, has gained increasing attention and become a hot research topic in recent years. M6A plays multifunctional roles in normal and abnormal biological processes, and its role may vary greatly depending on the position of the m6A motif. Programmed cell death (PCD) includes apoptosis, autophagy, pyroptosis, necroptosis and ferroptosis, most of which involve the breakdown of the plasma membrane. Based on the implications of m6A methylation on PCD, the regulators and functional roles of m6A methylation were comprehensively studied and reported. In this review, we focus on the high-complexity links between m6A and different types of PCD pathways, which are then closely associated with the initiation, progression and resistance of cancer. Herein, clarifying the relationship between m6A and PCD is of great significance to provide novel strategies for cancer treatment, and has a great potential prospect of clinical application.


Assuntos
Adenosina , Neoplasias , Adenosina/análogos & derivados , Adenosina/metabolismo , Apoptose/genética , Humanos , Metilação , Neoplasias/genética , Neoplasias/metabolismo
8.
Comput Math Methods Med ; 2022: 2427987, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339682

RESUMO

Background: Hepatocellular carcinoma (HCC) is one of the most common and lethal digestive system cancers worldwide. N6-methyladenosine (m6A) modification plays an essential role in diverse critical biological processes and may participate in the development and progression of HCC. Methods: We downloaded transcriptome data and clinical data from TCGA as the training set. COX and LASSO screened prognostic m6A genes. ROC and Kaplan-Meier curve analysis evaluated the effectiveness of the model. ICGC and our center data were used as verification sets. Results: We include the "writer (METTL3, METTL14, WTAP, KIAA1429, RBM15, ZC3H13)," the "reader (YTHDC1, YTHDC2, YTHDF1, YTHDF2, HNRNPC)," and the "eraser (FTO, ALKBH5)" in the study. We obtained YTHDF2, YTHDF1, METTL3, and KIAA1429 through differential analysis, survival analysis, and LASSO regression analysis. The prediction model was established based on the expression of these 4 molecules. HCC patients were divided into "high-risk" and "low-risk" groups to compare survival differences. The model suggested a poor prognosis in the validation sets. Conclusion: The four-m6A-related-gene combination model was an independent prognostic factor of HCC and could improve the prediction of the prognosis of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Metiltransferases/genética , Metiltransferases/metabolismo , Prognóstico , Adenosina/genética , Adenosina/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato
9.
Cell Rep ; 41(5): 111585, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36323256

RESUMO

Posttranscriptional RNA modifications by adenosine-to-inosine (A-to-I) editing are abundant in the brain, yet elucidating functional sites remains challenging. To bridge this gap, we investigate spatiotemporal and genetically regulated A-to-I editing sites across prenatal and postnatal stages of human brain development. More than 10,000 spatiotemporally regulated A-to-I sites were identified that occur predominately in 3' UTRs and introns, as well as 37 sites that recode amino acids in protein coding regions with precise changes in editing levels across development. Hyper-edited transcripts are also enriched in the aging brain and stabilize RNA secondary structures. These features are conserved in murine and non-human primate models of neurodevelopment. Finally, thousands of cis-editing quantitative trait loci (edQTLs) were identified with unique regulatory effects during prenatal and postnatal development. Collectively, this work offers a resolved atlas linking spatiotemporal variation in editing levels to genetic regulatory effects throughout distinct stages of brain maturation.


Assuntos
Inosina , Edição de RNA , Humanos , Animais , Camundongos , Edição de RNA/genética , Inosina/genética , Adenosina/metabolismo , Primatas , Regiões 3' não Traduzidas , Encéfalo/metabolismo , Adenosina Desaminase/metabolismo
10.
Clin Transl Med ; 12(11): e1075, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36324258

RESUMO

BACKGROUND: A number of studies have demonstrated that N6-methyladenosine (m6A) plays a vital role in the pathological process of various tumours. Recently, it was found that m6A writers or erasers affect the tumourigenesis of melanoma. However, the relationship between m6A readers such as YTH domain family (YTHDF) proteins and melanoma was still elusive. METHODS: RT-qPCR, Western blot and immunohistochemistry were conducted to measure the expression level of YTH N6-methyladenosine RNA binding protein 3 (YTHDF3) and lysyl oxidase-like 3 (LOXL3) in melanoma tissues and cells. The effects of YTHDF3 and LOXL3 on melanoma were verified in vitro and in vivo. Multi-omics analysis including RNA-seq, MeRIP-seq, RIP-seq and mass spectrometry analyses was performed to identify the target. The interaction between YTHDF3 and LOXL3 was verified by RT-PCR, Western blot, MeRIP-qPCR, RIP-qPCR and CRISPR-Cas13b-based epitranscriptome engineering. RESULTS: In this study, we found that m6A reader YTHDF3 could affect the metastasis of melanoma both in vitro and in vivo. The downstream targets of YTHDF3, such as LOXL3, phosphodiesterase 3A (PDE3A) and chromodomain helicase DNA-binding protein 7 (CHD7) were identified by means of RNA-seq, MeRIP-seq, RIP-seq and mass spectrometry analyses. Besides, RT-qPCR, Western blot, RIP-qPCR and MeRIP-qPCR were performed for subsequent validation. Among various targets of YTHDF3, LOXL3 was found to be the optimal target of YTHDF3. With the application of CRISPR-Cas13b-based epitranscriptome engineering, we further confirmed that the transcript of LOXL3 was captured and regulated by YTHDF3 via m6A binding sites. YTHDF3 augmented the protein expression of LOXL3 without affecting its mRNA level via the enrichment of eukaryotic translation initiation factor 3 subunit A (eIF3A) on the transcript of LOXL3. LOXL3 downregulation inhibited the metastatic ability of melanoma cells, and overexpression of LOXL3 ameliorated the inhibition of melanoma metastasis caused by YTHDF3 downregulation. CONCLUSIONS: The YTHDF3-LOXL3 axis could serve as a promising target to be interfered with to inhibit the metastasis of melanoma.


Assuntos
Melanoma , Proteínas de Ligação a RNA , Humanos , Proteínas de Ligação a RNA/genética , Adenosina/metabolismo , Melanoma/genética , RNA Mensageiro/genética , Aminoácido Oxirredutases/metabolismo
11.
Front Immunol ; 13: 1012534, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36341324

RESUMO

Adenosine triphosphate (ATP) represents a danger signal that accumulates in injured tissues, in inflammatory sites, and in the tumor microenvironment. ATP promotes tumor growth but also anti-tumor immune responses notably via the P2X7 receptor. ATP can also be catabolized by CD39 and CD73 ecto-enzymes into immunosuppressive adenosine. P2X7, CD39 and CD73 have attracted much interest in cancer as targets offering the potential to unleash anti-tumor immune responses. These membrane proteins represent novel purinergic checkpoints that can be targeted by small drugs or biologics. Here, we investigated nanobody-based biologics targeting mainly P2X7, but also CD73, alone or in combination therapies. Blocking P2X7 inhibited tumor growth and improved survival of mice in cancer models that express P2X7. P2X7-potentiation by a nanobody-based biologic was not effective alone to control tumor growth but enhanced tumor control and immune responses when used in combination with oxaliplatin chemotherapy. We also evaluated a bi-specific nanobody-based biologic that targets PD-L1 and CD73. This novel nanobody-based biologic exerted a potent anti-tumor effect, promoting tumor rejection and improving survival of mice in two tumor models. Hence, this study highlights the importance of purinergic checkpoints in tumor control and open new avenues for nanobody-based biologics that may be further exploited in the treatment of cancer.


Assuntos
Neoplasias , Microambiente Tumoral , Camundongos , Animais , Trifosfato de Adenosina/metabolismo , Adenosina , Oxaliplatina
12.
Int J Mol Sci ; 23(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36361618

RESUMO

Adenosine A2A receptors (A2AR) control fear memory and the underlying processes of synaptic plasticity in the amygdala. In other brain regions, A2AR activation is ensured by ATP-derived extracellular adenosine formed by ecto-5'-nucleotidase or CD73. We now tested whether CD73 is also responsible to provide for the activation of A2AR in controlling fear memory and amygdala long-term potentiation (LTP). The bilateral intracerebroventricular injection of the CD73 inhibitor αß-methylene ADP (AOPCP, 1 nmol/ventricle/day) phenocopied the effect of the A2AR blockade by decreasing the expression of fear memory, an effect disappearing in CD73-knockout (KO) mice and in forebrain neuronal A2AR-KO mice. In the presence of PPADS (20 µM) to eliminate any modification of ATP/ADP-mediated P2 receptor effects, both AOPCP (100 µM) and the A2AR antagonist, SCH58261 (50 nM), decreased LTP magnitude in synapses of projection from the external capsula into the lateral amygdala, an effect eliminated in slices from both forebrain neuronal A2AR-KO mice and CD73-KO mice. These data indicate a key role of CD73 in the process of A2AR-mediated control of fear memory and underlying synaptic plasticity processes in the amygdala, paving the way to envisage CD73 as a new therapeutic target to interfere with abnormal fear-like emotional processing.


Assuntos
5'-Nucleotidase , Receptor A2A de Adenosina , Camundongos , Animais , 5'-Nucleotidase/genética , 5'-Nucleotidase/metabolismo , Receptor A2A de Adenosina/genética , Receptor A2A de Adenosina/metabolismo , Adenosina/metabolismo , Camundongos Endogâmicos C57BL , Tonsila do Cerebelo/metabolismo , Camundongos Knockout , Medo/fisiologia , Difosfato de Adenosina , Trifosfato de Adenosina/metabolismo
13.
Int J Mol Sci ; 23(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36362112

RESUMO

Adenosine receptors (ARs) are involved in the suppression and development of inflammatory and fibrotic conditions. Specifically, AR activation promotes differentiation of lung fibroblasts into myofibroblasts, typical of a fibrotic event. Pulmonary fibrosis is a severe disease characterized by inflammation and fibrosis of unknown etiology and lacking an effective treatment. The present investigation explored the action of MRS5980, a new, highly potent and selective A3AR agonist, in an established murine model of lung fibrosis. The effects of either vehicle or MRS5980 were studied in mice following intratracheal bleomycin administration. We evaluated the role of the A3AR agonist on lung stiffness, studying the airway resistance to inflation, oxidative stress (8-OHdG and MDA), inflammation, pro- and anti-inflammatory marker levels (IL-1ß, IL-6, TNF-α, IL-10 and IL-17A) and fibrosis establishment, evaluating transforming growth factor (TGF)-ß expression and α-smooth muscle actin (α-SMA) deposition in lungs. Bleomycin administration increased lung stiffness, TGF-ß levels, α-SMA deposition, and inflammatory and oxidative stress markers. The treatment with MRS5980 attenuated all the analyzed functional, biochemical and histopathological markers in a dose-dependent manner. Our findings support the therapeutic potential of A3AR agonists in lung fibrosis by demonstrating reduced disease progression, as indicated by decreased inflammation, TGF-ß expression and fibrotic remodeling.


Assuntos
Fibrose Pulmonar , Camundongos , Animais , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Bleomicina/farmacologia , Camundongos Endogâmicos C57BL , Pulmão/patologia , Fator de Crescimento Transformador beta/metabolismo , Fibroblastos/metabolismo , Fibrose , Inflamação/patologia , Receptores Purinérgicos P1/metabolismo , Adenosina/metabolismo
14.
Int J Mol Sci ; 23(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36362227

RESUMO

The adenosine A2A and A2B receptors are promising therapeutic targets in the treatment of obesity and diabetes since the agonists and antagonists of these receptors have the potential to positively affect metabolic disorders. The present study investigated the link between body weight reduction, glucose homeostasis, and anti-inflammatory activity induced by a highly potent and specific adenosine A2B receptor antagonist, compound PSB-603. Mice were fed a high-fat diet for 14 weeks, and after 12 weeks, they were treated for 14 days intraperitoneally with the test compound. The A1/A2A/A2B receptor antagonist theophylline was used as a reference. Following two weeks of treatment, different biochemical parameters were determined, including total cholesterol, triglycerides, glucose, TNF-α, and IL-6 blood levels, as well as glucose and insulin tolerance. To avoid false positive results, mouse locomotor and spontaneous activities were assessed. Both theophylline and PSB-603 significantly reduced body weight in obese mice. Both compounds had no effects on glucose levels in the obese state; however, PSB-603, contrary to theophylline, significantly reduced triglycerides and total cholesterol blood levels. Thus, our observations showed that selective A2B adenosine receptor blockade has a more favourable effect on the lipid profile than nonselective inhibition.


Assuntos
Doenças Metabólicas , Antagonistas de Receptores Purinérgicos P1 , Camundongos , Animais , Antagonistas de Receptores Purinérgicos P1/uso terapêutico , Antagonistas do Receptor A2 de Adenosina/farmacologia , Antagonistas do Receptor A2 de Adenosina/uso terapêutico , Antagonistas do Receptor A2 de Adenosina/metabolismo , Teofilina , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Peso Corporal , Adenosina/farmacologia , Glucose/metabolismo , Nucleosídeos de Purina , Colesterol/uso terapêutico , Triglicerídeos/uso terapêutico , Receptor A2B de Adenosina/metabolismo
15.
Int J Mol Sci ; 23(21)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36362385

RESUMO

The universal N6-threonylcarbamoyladenosine (t6A) modification occurs at position 37 of tRNAs that decipher codons starting with adenosine. Mechanistically, t6A stabilizes structural configurations of the anticodon stem loop, promotes anticodon-codon pairing and safeguards the translational fidelity. The biosynthesis of tRNA t6A is co-catalyzed by two universally conserved protein families of TsaC/Sua5 (COG0009) and TsaD/Kae1/Qri7 (COG0533). Enzymatically, TsaC/Sua5 protein utilizes the substrates of L-threonine, HCO3-/CO2 and ATP to synthesize an intermediate L-threonylcarbamoyladenylate, of which the threonylcarbamoyl-moiety is subsequently transferred onto the A37 of substrate tRNAs by the TsaD-TsaB -TsaE complex in bacteria or by the KEOPS complex in archaea and eukaryotic cytoplasm, whereas Qri7/OSGEPL1 protein functions on its own in mitochondria. Depletion of tRNA t6A interferes with protein homeostasis and gravely affects the life of unicellular organisms and the fitness of higher eukaryotes. Pathogenic mutations of YRDC, OSGEPL1 and KEOPS are implicated in a number of human mitochondrial and neurological diseases, including autosomal recessive Galloway-Mowat syndrome. The molecular mechanisms underscoring both the biosynthesis and cellular roles of tRNA t6A are presently not well elucidated. This review summarizes current mechanistic understandings of the catalysis, regulation and disease implications of tRNA t6A-biosynthetic machineries of three kingdoms of life, with a special focus on delineating the structure-function relationship from perspectives of conservation and diversity.


Assuntos
Anticódon , RNA de Transferência , Humanos , RNA de Transferência/metabolismo , Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação ao GTP/metabolismo
16.
Molecules ; 27(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36364238

RESUMO

As a cellular protease, transmembrane serine protease 2 (TMPRSS2) plays roles in various physiological and pathological processes, including cancer and viral entry, such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Herein, we conducted expression, mutation, and prognostic analyses for the TMPRSS2 gene in pan-cancers as well as in COVID-19-infected lung tissues. The results indicate that TMPRSS2 expression was highest in prostate cancer. A high expression of TMPRSS2 was significantly associated with a short overall survival in breast invasive carcinoma (BRCA), sarcoma (SARC), and uveal melanoma (UVM), while a low expression of TMPRSS2 was significantly associated with a short overall survival in lung adenocarcinoma (LUAD), demonstrating TMPRSS2 roles in cancer patient susceptibility and severity. Additionally, TMPRSS2 expression in COVID-19-infected lung tissues was significantly reduced compared to healthy lung tissues, indicating that a low TMPRSS2 expression may result in COVID-19 severity and death. Importantly, TMPRSS2 mutation frequency was significantly higher in prostate adenocarcinoma (PRAD), and the mutant TMPRSS2 pan-cancer group was significantly associated with long overall, progression-free, disease-specific, and disease-free survival rates compared to the wild-type (WT) TMPRSS2 pan-cancer group, demonstrating loss of functional roles due to mutation. Cancer cell lines were treated with small molecules, including cordycepin (CD), adenosine (AD), thymoquinone (TQ), and TQFL12, to mediate TMPRSS2 expression. Notably, CD, AD, TQ, and TQFL12 inhibited TMPRSS2 expression in cancer cell lines, including the PC3 prostate cancer cell line, implying a therapeutic role for preventing COVID-19 in cancer patients. Together, these findings are the first to demonstrate that small molecules, such as CD, AD, TQ, and TQFL12, inhibit TMPRSS2 expression, providing novel therapeutic strategies for preventing COVID-19 and cancers.


Assuntos
COVID-19 , Neoplasias Pulmonares , Neoplasias da Próstata , Masculino , Humanos , SARS-CoV-2 , COVID-19/tratamento farmacológico , COVID-19/genética , Prognóstico , Adenosina , Mutação , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Serina Endopeptidases/genética
17.
Mediators Inflamm ; 2022: 4766992, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36330380

RESUMO

N6-methyladenosine (m6A) modification is the most prevalent chemical modification in eukaryotic mRNA and is associated with the development of various immune diseases. However, the role of m6A methylation in rheumatoid arthritis (RA) development is unclear. We preliminarily explored the role of m6A methylation-related mRNAs in RA for its clinical application. The discovery of m6A methylation-modifying genes in this study may provide a fresh perspective on the development of drugs for RA treatment. High-throughput sequencing combined with methylated RNA immunoprecipitation (MeRIP-seq) and RNA sequencing were used to assess whole-transcriptome m6A modifications in the synovium of patients with RA. The relationship between m6A-modified target genes and RA inflammation and macrophages was determined. The expression of the m6A-modified significant transcript-enriched inflammatory signaling pathway was assessed through animal experiments. Differentially expressed m6A genes were correlated with macrophage activation involved in immune response, vascular endothelium, MAPK signaling pathway, PI3K - Akt signaling pathway, and other inflammatory processes. Furthermore, combined analysis with m6A-seq and RNA-seq revealed 120 genes with significant changes in both m6A modification and mRNA expression. We selected the top 3 candidate mRNAs that were upregulated and downregulated simultaneously. The expression of phosphatase and tensin homolog deleted on chromosome ten (PTEN) mRNA and protein in RA patients was lower than that in healthy control (HC). SHC-binding protein 1 (SHCBP1) and neurexophilin-3 (NXPH3) mRNA expressions were increased in RA patients. The expression of M1 macrophages was increased in RA patients. RA markers are such as rheumatoid factor (RF) and peptide containing citrulline (CCP). Further animal experiments showed that the expression of synovial MAPK, PI3K, and Akt1 proteins in the RA model was increased, and the PTEN, p-PTEN protein expression was decreased. PI3K, Akt1, PTEN, and p-PTEN were correlated to RA joint inflammation. This study revealed a unique pattern of differential m6A methylation modifications in RA and concluded that m6A modification is related to the occurrence of RA synovial inflammation.


Assuntos
Artrite Reumatoide , Transcriptoma , Animais , Metilação , Transcriptoma/genética , Adenosina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Artrite Reumatoide/genética , Artrite Reumatoide/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inflamação/genética
18.
Int J Oncol ; 61(6)2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36321774

RESUMO

As one of the three major malignant tumor types of the female reproductive system, endometrial cancer (EC) is the most prevalent gynecologic cancer in developed countries. In recent years, the incidence of EC has increased worldwide, threatening the health and well­being of women. Recent research has indicated that the expression of multiple N6­methyladenosine (m6A) regulators is up­ or downregulated in EC and that abnormalities in m6A methylation and the expression of associated regulators are critical to the pathogenesis and progression of EC. m6A is the most abundant internal modification of mRNA. Several studies have demonstrated a close association between the development and progression of malignant tumors and the epigenetic phenomenon of m6A methylation. In the present study, the current status of research on m6A methylation in EC was reviewed. The mechanisms of methyltransferase, demethylase and m6A binding protein in regulating the development and progression of EC by modifying mRNA were introduced. The related research results will provide novel methods and approaches for the prevention and treatment of EC.


Assuntos
Adenosina , Neoplasias do Endométrio , Feminino , Humanos , Metilação , Metiltransferases/metabolismo , RNA Mensageiro/metabolismo , RNA/genética
19.
Discov Med ; 34(172): 115-129, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36333113

RESUMO

Poly (ADP-ribose) polymerase 1 (PARP1) plays an irreplaceable role in the progression of diabetic retinopathy (DR). The m6A methylation in mRNA controls gene expression under various physiological and pathological conditions. However, effects of m6A methylation on PARP1 expression and DR progression at molecular level have not been documented. This study shows that the levels of PARP1, inflammatory factors, and fibrosis markers were significantly upregulated via evaluation by real-time PCR, western blotting, and immunofluorescence in both in vivo and in vitro experiments. EdU, CCK8, and apoptosis assays demonstrate that knockdown of PARP1 not only significantly improved the vitality of hRMECs (human retinal microvascular endothelial cells) even under high glucose conditions but also prevented glucose-induced inflammation, fibrosis, and angiogenesis in vivo. Mechanistically, dot blot, RNA pull-down, and immunoblots were implemented to explore the mechanism of m6A-mediated PARP1 stability and function. PARP1 is identified as a target of YTHDF2-mediated m6A modification. Overexpression of YTHDF2 substantially suppressed PARP1 mRNA m6A modification and inhibited its mRNA expression. Collectively, it has been demonstrated that PARP1 is frequently upregulated in human retinas and contributes to DR progression, and that YTHDF2-mediated m6A modification epigenetically regulates diabetes-induced PARP1 expression. Findings from this work may engender therapeutic targets for treating diabetic retinopathy.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Hiperglicemia , Humanos , Retinopatia Diabética/genética , Células Endoteliais , Adenosina/metabolismo , RNA Mensageiro/genética , Hiperglicemia/genética , Glucose , Fibrose , Poli(ADP-Ribose) Polimerase-1/genética
20.
Front Endocrinol (Lausanne) ; 13: 1007801, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36407311

RESUMO

Despite great efforts, effective treatment against cancer has not yet been found. However, natural compounds such as the polyphenol resveratrol have emerged as promising preventive agent in cancer therapy. The mode of action of resveratrol is still poorly understood, but it can modulate many signaling pathways related to the initiation and progression of cancer. Adenosinergic signaling may be involved in the antitumoral action of resveratrol since resveratrol binds to the orthosteric binding site of adenosine A2A receptors and acts as a non-selective agonist for adenosine receptors. In the present study, we measured the impact of resveratrol treatment on different adenosinergic pathway components (i.e. adenosine receptors levels, 5'-nucleotidase, adenosine deaminase, and adenylyl cyclase activities, protein kinase A levels, intracellular adenosine and other related metabolites levels) and cell viability and proliferation in HeLa and SH-SY5Y cell lines. Results revealed changes leading to turning off cAMP signaling such as decreased levels of A2A receptors and reduced adenylyl cyclase activation, increased levels of A1 receptors and increased adenylyl cyclase inhibition, and lower levels of PKA. All these changes could contribute to the antitumoral action of resveratrol. Interestingly, these effects were almost identical in HeLa and SH-SY5Y cells suggesting that resveratrol enhances A1 and hinders A2A adenosine receptors signaling as part of a potential mechanism of antitumoral action.


Assuntos
Adenilil Ciclases , Neuroblastoma , Humanos , Resveratrol/farmacologia , Adenilil Ciclases/metabolismo , Receptores Purinérgicos P1/metabolismo , Adenosina/farmacologia
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