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1.
Mol Cell ; 81(21): 4493-4508.e9, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34555354

RESUMO

Initiation is the rate-limiting step in translation, and its dysregulation is vital for carcinogenesis, including hematopoietic malignancy. Thus, discovery of novel translation initiation regulators may provide promising therapeutic targets. Here, combining Ribo-seq, mass spectrometry, and RNA-seq datasets, we discovered an oncomicropeptide, APPLE (a peptide located in ER), encoded by a non-coding RNA transcript in acute myeloid leukemia (AML). APPLE is overexpressed in various subtypes of AML and confers a poor prognosis. The micropeptide is enriched in ribosomes and regulates the initiation step to enhance translation and to maintain high rates of oncoprotein synthesis. Mechanically, APPLE promotes PABPC1-eIF4G interaction and facilitates mRNA circularization and eIF4F initiation complex assembly to support a specific pro-cancer translation program. Targeting APPLE exhibited broad anti-cancer effects in vitro and in vivo. This study not only reports a previously unknown function of micropeptides but also provides new opportunities for targeting the translation machinery in cancer cells.


Assuntos
Fator de Iniciação 4F em Eucariotos/química , Fator de Iniciação Eucariótico 4G/metabolismo , Neoplasias Hematológicas/metabolismo , Peptídeos/química , Biossíntese de Proteínas , Animais , Progressão da Doença , Genoma Humano , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fases de Leitura Aberta , Polirribossomos/química , RNA Mensageiro/metabolismo , RNA não Traduzido/metabolismo , Proteínas de Ligação a RNA/genética , Ribossomos/metabolismo , Sensibilidade e Especificidade , Resultado do Tratamento
2.
Nucleic Acids Res ; 52(11): 6360-6375, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38682589

RESUMO

Although DNA-PK inhibitors (DNA-PK-i) have been applied in clinical trials for cancer treatment, the biomarkers and mechanism of action of DNA-PK-i in tumor cell suppression remain unclear. Here, we observed that a low dose of DNA-PK-i and PARP inhibitor (PARP-i) synthetically suppresses BRCA-deficient tumor cells without inducing DNA double-strand breaks (DSBs). Instead, we found that a fraction of DNA-PK localized inside of nucleoli, where we did not observe obvious DSBs. Moreover, the Ku proteins recognize pre-rRNA that facilitates DNA-PKcs autophosphorylation independent of DNA damage. Ribosomal proteins are also phosphorylated by DNA-PK, which regulates pre-rRNA biogenesis. In addition, DNA-PK-i acts together with PARP-i to suppress pre-rRNA biogenesis and tumor cell growth. Collectively, our studies reveal a DNA damage repair-independent role of DNA-PK-i in tumor suppression.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA , Proteína Quinase Ativada por DNA , Autoantígeno Ku , Precursores de RNA , Proteína Quinase Ativada por DNA/metabolismo , Proteína Quinase Ativada por DNA/genética , Humanos , Precursores de RNA/metabolismo , Precursores de RNA/genética , Linhagem Celular Tumoral , Autoantígeno Ku/metabolismo , Autoantígeno Ku/genética , Fosforilação , Nucléolo Celular/metabolismo , Nucléolo Celular/genética , Nucléolo Celular/efeitos dos fármacos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , RNA Ribossômico/metabolismo , RNA Ribossômico/genética , Animais , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo
3.
Med Res Rev ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515232

RESUMO

Atropisomerism, an expression of axial chirality caused by limited bond rotation, is a prominent aspect within the field of medicinal chemistry. It has been shown that atropisomers of a wide range of compounds, including established FDA-approved drugs and experimental molecules, display markedly different biological activities. The time-dependent reversal of chirality in atropisomers poses complexity and obstacles in the process of drug discovery and development. Nonetheless, recent progress in understanding atropisomerism and enhanced characterization methods have greatly assisted medicinal chemists in the effective development of atropisomeric drug molecules. This article provides a comprehensive review of their special design thoughts, synthetic routes, and biological activities, serving as a reference for the synthesis and biological evaluation of bioactive atropisomers in the future.

4.
J Am Chem Soc ; 146(6): 3764-3772, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38304977

RESUMO

TiO2-supported Pt species have been widely applied in numerous critical reactions involving photo-, thermo-, and electrochemical-catalysis for decades. Manipulation of the state of the Pt species in Pt/TiO2 catalysts is crucial for fine-tuning their catalytic performance. Here, we report an interesting discovery showing the epitaxial growth of PtO2 atomic layers on rutile TiO2, potentially allowing control of the states of active Pt species in Pt/TiO2 catalysts. The presence of PtO2 atomic layers could modulate the geometric configuration and electronic state of the Pt species under reduction conditions, resulting in a spread of the particle shape and obtaining a Pt/PtO2/TiO2 structure with more positive valence of Pt species. As a result, such a catalyst exhibits exceptional electrocatalytic activity and stability toward hydrogen evolution reaction, while also promoting the thermocatalytic CO oxidation, surpassing the performance of the Pt/TiO2 catalyst with no epitaxial structure. This novel epitaxial growth of the PtO2 structure on rutile TiO2 in Pt/TiO2 catalysts shows its potential in the rational design of highly active and economical catalysts toward diverse catalytic reactions.

5.
FASEB J ; 37(11): e23265, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37874273

RESUMO

Mitochondrial dysfunction plays an important role in the onset and progression of podocyte injury and proteinuria. However, the process by which the change in the podocyte mitochondria occurs is not well understood. Uncoupling protein 2 (UCP2) is a mitochondrial anion carrier protein, which is located in the mitochondrial inner membrane. Here, we reported that mice with podocyte-specific Ucp2 deficiency developed podocytopathy with proteinuria with aging. Furthermore, those mice exhibited increased proteinuria in experimental models evoked by Adriamycin. Our findings suggest that UCP2 mediates mitochondrial dysfunction by regulating mitochondrial dynamic balance. Ucp2-deleted podocytes exhibited increased mitochondrial fission and deficient in ATP production. Mechanistically, opacity protein 1 (OPA1), a key protein in fusion of mitochondrial inner membrane, was regulated by UCP2. Ucp2 deficiency promoted proteolysis of OPA1 by activation OMA1 which belongs to mitochondrial inner membrane zinc metalloprotease. Those finding demonstrate the role of UCP2 in mitochondrial dynamics in podocytes and provide new insights into pathogenesis associated with podocyte injury and proteinuria.


Assuntos
Podócitos , Proteólise , Animais , Camundongos , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Metaloproteases/genética , Metaloproteases/metabolismo , Dinâmica Mitocondrial , Proteínas Mitocondriais/metabolismo , Podócitos/metabolismo , Proteinúria/metabolismo , Proteína Desacopladora 2/genética , Proteína Desacopladora 2/metabolismo
6.
BMC Public Health ; 24(1): 1367, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773446

RESUMO

BACKGROUND: We previously conducted a case-control study and found that exposure to electronic screen before nocturnal sleep was associated with hypertensive disorders in pregnancy (HDP). Hence, we carried out this cohort study aiming to identify the effects of screen exposure time on the incidence rate and severity of HDP. METHODS: A retrospective cohort study was conducted from January 2022 and July 2022 from three hospitals in Wuxi and Changzhou cities. A total of 732 women were recruited and the information included socio-demographic characteristics, screen exposure and outcomes. Generalized estimating equations and binary non-conditional logistic models were applied to multivariate analysis, calculating the odds ratios (ORs) and 95% confidence intervals (CIs) of screen exposure time. RESULTS: The duration order of total screen time was smartphone > computer > television, while the duration order of screen time before nocturnal sleep was smartphone > television > computer. Multivariate analyses showed that the susceptibility of HDP among women who exposed to television before nocturnal sleep was 81.5% percent higher than those not exposed (P = 0.018, OR[95%CI] = 1.815[1.106-2.981]). In addition, total daily exposure time of television in the third trimester of pregnancy significantly increased the severity of HDP (P = 0.021, OR[95%CI] = 3.641[1.213-10.927]). CONCLUSIONS: Based on this preliminary study, we would suggest that pregnant women do not watch television before nocturnal sleep. While in the third trimester of pregnancy, total exposure time of television should be limited. Investigations from other areas and experimental studies should be conducted to verify the conclusion.


Assuntos
Hipertensão Induzida pela Gravidez , Tempo de Tela , Humanos , Feminino , Gravidez , Estudos Retrospectivos , Adulto , Hipertensão Induzida pela Gravidez/epidemiologia , China/epidemiologia , Smartphone/estatística & dados numéricos , Televisão/estatística & dados numéricos , Fatores de Risco , Incidência , Adulto Jovem , Fatores de Tempo
7.
Nano Lett ; 23(23): 11314-11322, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38018816

RESUMO

The electrochemical 5-hydroxymethylfurfural oxidation reaction (HMFOR) has been regarded as a viable alternative to sustainable biomass valorization. However, the transformation of the catalysts under harsh electrooxidation conditions remains controversial. Herein, we confirm the self-construction of cuprous sulfide nanosheets (Cu2S NSs) into sulfate-terminated copper oxide nanorods (CuO-SO42- NRs) during the first-cycle of the HMFOR, which achieves a near-quantitative synthesis of 2,5-furandicarboxylic acid (FDCA) with a >99.9% yield and faradaic efficiency without deactivation in 15 successive cycles. Electrochemical impedance spectroscopies confirm that the surface SO42- effectively reduces the onset potential for HMFOR, while in situ Raman spectroscopies identify a reversible transformation from CuII-O to CuIII-OOH in HMFOR. Furthermore, density functional theory calculations reveal that the surface SO42- weakens the Cu-OH bonds in CuOOH to promote the rate-determining step of its coupling with the C atom in HMF-H* resulting from HMF hydrogenation, which synergistically enhances the catalytic activity of CuO-SO42- NRs toward HMF-to-FDCA conversion.

8.
Psychol Health Med ; : 1-19, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503424

RESUMO

Suicide among college students is a challenging problem globally. Yet, the association between sleep quality, depressive symptoms, and suicidal ideation remains unclear. This study aims to understand if depressive symptoms mediate the relationship between sleep quality and suicide ideation and whether the interaction between depressive symptoms and sleep quality on suicidal ideation is additive. A total of 1182 college students were recruited, and sleep quality, depressive symptoms, and suicidal ideation were assessed using questionnaires. Univariate analysis, logistic regression analysis, linear regression models, and the Sobel test were performed. The results showed that, among college students, poor sleep quality was positively associated with suicidal ideation, and the association was mediated through depressive symptoms. Moreover, there was a significant additive interaction between poor sleep quality and depressive symptoms on suicidal ideation. These findings suggest that, in the process of preventing and treating suicidal ideation in college students with sleep disorders, we should focus on the evaluation and intervention of depressive symptoms and adopt multidisciplinary team interventions for college students with sleep disorders and depression.

9.
Int J Mol Sci ; 25(4)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38396956

RESUMO

Ramshorn snails from the family Planorbidae are important freshwater snails due to their low trophic level, and some of them act as intermediate hosts for zoonotic trematodes. There are about 250 species from 40 genera of Planorbidae, but only 14 species from 5 genera (Anisus, Biomphalaria, Bulinus, Gyraulus, and Planorbella) have sequenced complete mitochondrial genomes (mitogenomes). In this study, we sequenced and assembled a high-quality mitogenome of a ramshorn snail, Polypylis sp. TS-2018, which represented the first mitogenome of the genus. The mitogenome of Polypylis sp. TS-2018 is 13,749 bp in length, which is shorter than that of most gastropods. It contains 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, and 2 ribosomal RNA (rRNA). We compared mitogenome characteristics, selection pressure, and gene rearrangement among all of the available mitogenomes of ramshorn snails. We found that the nonsynonymous and synonymous substitution rates (Ka/Ks) of most PCGs indicated purifying and negative selection, except for atp8 of Anisus, Biomphalaria, and Gyraulus, which indicated positive selection. We observed that transpositions and reverse transpositions occurred on 10 tRNAs and rrnS, which resulted in six gene arrangement types. We reconstructed the phylogenetic trees using the sequences of PCGs and rRNAs and strongly supported the monophyly of each genus, as well as three tribes in Planorbidae. Both the gene rearrangement and phylogenetic results suggested that Polypylis had a close relationship with Anisus and Gyraulus, while Bulinus was the sister group to all of the other genera. Our results provide useful data for further investigation of species identification, population genetics, and phylogenetics among ramshorn snails.


Assuntos
Acanthaceae , Genoma Mitocondrial , Animais , Filogenia , Genoma Mitocondrial/genética , Caramujos/genética , RNA Ribossômico/genética , RNA de Transferência/genética
10.
Aust Crit Care ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38762342

RESUMO

AIM: The aim of this study was to test whether rumination and negative affectivity mediate the relationship between work-family conflict and nurse-assessed patient safety among intensive care unit nurses. BACKGROUND: Most intensive care unit nurses experience work-family conflicts that jeopardise patient safety. Although prior studies have explored the effect of work-family conflict on patient safety, few have investigated whether work-family conflict is associated with patient safety through rumination and negative affectivity among intensive care unit nurses. DESIGN: Cross-sectional study. METHODS: This study included 209 intensive care unit nurses from five general hospitals. The Work-Family Conflict Scale, the Ruminative Response Scale, the Positive and Negative Affect Schedule-Negative Affectivity, and three items indicating nurses' perception of overall patient safety were used to gather data. Associations between work-family conflict, rumination, negative affectivity, and nurse-assessed patient safety were assessed using correlation and serial multiple mediation analysis. RESULTS: Work-family conflict, rumination, negative affectivity, and nurse-assessed patient safety were significantly correlated (p < 0.01). Work-family conflict can have not only a direct negative impact on the nurse-assessed patient safety (effect = -0.0234; standard error [SE] = 0.0116; 95% confidence interval [CI]: lower limit [LL] = -0.0464, upper limit [UL] = -0.0005) but also an indirect impact on nurse-assessed patient safety through three paths: the independent mediating role of rumination (effect = -0.0118; SE = 0.0063; 95% CI: LL = -0.0251, UL = -0.0006), the independent mediating role of negative affectivity (effect = -0.0055; SE = 0.0039; 95% CI: LL = -0.0153, UL = -0.0001), and the chain-mediating role of rumination and negative affectivity (effect = -0.0078; SE = 0.0031; 95% CI: LL = -0.0152, UL = -0.0027). CONCLUSION: Our findings indicated that work-family conflict could influence nurse-assessed patient safety through increasing rumination and negative affectivity among intensive care unit nurses. Based on the results, interventions aimed at decreasing work-family conflict would be beneficial for intensive care unit nurses' emotional stability and patient safety.

11.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(1): 190-197, 2024 Jan 20.
Artigo em Zh | MEDLINE | ID: mdl-38322514

RESUMO

Objective: To create a novel chitosan antibacterial hemostatic sponge (NCAHS) and to evaluate its material and biological properties. Methods: Chitosan, a polysaccharide, was used as the sponge substrate and different proportions of sodium tripolyphosphate (STPP), glycerol, and phenol sulfonyl ethylamine were added to prepare the sponges through the freeze-drying method. The whole-blood coagulation index (BCI) was used as the screening criterion to determine the optimal concentrations of chitosan and the other additives and the hemostatic sponges were prepared accordingly. Zein/calcium carbonate (Zein/CaCO3) composite microspheres loaded with ciprofloxacin hydrochloride were prepared and added to the hemostatic sponges to obtain NCAHS. Scanning electron microscope was used to observe the microscopic morphology and porosity of the NCAHS. The water absorption rate, in vitro antibacterial susceptibility rate against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), in vitro coagulation performance, and hemocompatibility of NCAHS were examined. The coagulation performance of NCAHS was evaluated by using rabbit liver injury and rabbit auricular artery hemorrhageear models and commercial hemostatic sponge (CHS) was used as a control. The in vivo biocompatibility, including such aspects as cytotoxicity, skin irritation in animals, and acute in vivo toxicity, of the NCAHS extracts was examined by using as a reference the national standards for biological evaluation of medical devices. Results: The NCAHS prepared with 1.5% chitosan (W/V), 0.01% STPP (W/V), 0% glycerol (V/V), 0.15% phenol-sulfonyl-ethylamine (V/V), Zein and CaCO3 at the mixing ratio of 5∶1 (W/W), Zein at the final mass concentration of 2.5 g/L, and ethanol at the final concentration of 17.5% (V/V) were fine and homogeneous, possessing a honeycomb-like porous structure with a pore size of about 200 µm. The NCAHS thus prepared had the lowest BCI value. The water absorption ([2362.16±201.15] % vs. [1102.56±91.79]%) and in vitro coagulation performance (31.338% vs. 1.591%) of NCAHS were significantly better than those of CHS (P<0.01). Tests with the in vivo auricular artery hemorrhage model ([36.00±13.42] s vs. [80.00±17.32] s) and rabbit liver bleeding model ([30.00±0] s vs. [70.00±17.32] s) showed that the hemostasis time of NCAHS was significantly shorter than that of CHS (P<0.01). NCAHS had significant inhibitory ability against S. aureus and E. coli. In addition, NCAHS showed good in vitro and in vivo biocompatibility. Conclusion: NCAHS is a composite sponge that shows excellent antimicrobial properties, hemostatic effect, and biocompatibility. Therefore, its extensive application in clinical settings is warranted.


Assuntos
Quitosana , Hemostáticos , Zeína , Animais , Coelhos , Quitosana/química , Hemostáticos/farmacologia , Escherichia coli , Glicerol/farmacologia , Staphylococcus aureus , Zeína/farmacologia , Hemostasia , Antibacterianos/farmacologia , Hemorragia , Água/farmacologia , Etilaminas/farmacologia , Fenóis/farmacologia
12.
Angew Chem Int Ed Engl ; 63(5): e202312663, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38032817

RESUMO

Azomethine imines, as a prominent class of 1,3-dipolar species, hold great significance and potential in organic and medicinal chemistry. However, the reported synthesis of centrally chiral azomethine imines relies on kinetic resolution, and the construction of axially chiral azomethine imines remains unexplored. Herein, we present the synthesis of axially chiral azomethine imines through copper- or chiral phosphoric acid catalyzed ring-closure reactions of N'-(2-alkynylbenzylidene)hydrazides, showcasing high efficiency, mild conditions, broad substrate scope, and excellent enantioselectivity. Furthermore, the biological evaluation revealed that the synthesized axially chiral azomethine imines effectively protect dorsal root ganglia (DRG) neurons by inhibiting apoptosis induced by oxaliplatin, offering a promising therapeutic approach for chemotherapy-induced peripheral neuropathy (CIPN). Remarkably, the (S)- and (R)-atropisomers displayed distinct neuroprotective activities, underscoring the significance of axial stereochemistry.


Assuntos
Compostos Azo , Iminas , Tiossemicarbazonas , Estereoisomerismo , Compostos Azo/farmacologia , Catálise
13.
Anal Chem ; 95(13): 5780-5787, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36939176

RESUMO

Intracellular peroxynitrite anions (ONOO-) and microenvironments (such as viscosity and polarity) play an important role in maintaining redox homeostasis, regulating diffusion, transportation, and signal transduction in living cells. The abnormality of these factors is often closely related to various physiological/pathological processes. However, owing to the lack of suitable probes, the simultaneous visualization of ONOO-, viscosity, and polarity in ferroptosis and cancer models has not been achieved. To meet urgent needs, we presented a multifunctional near-infrared (NIR) fluorescent probe, named MQA-P, for simultaneously detecting ONOO-, viscosity, and polarity within mitochondria. The probe exhibited a remarkable turn-on response to ONOO- with the far-red emission of about 645 nm and was highly sensitive to viscosity/polarity in the NIR channel with λem > 704 nm. Facilitated by MQA-P, for the first time, we revealed that erastin-induced ferroptosis was accompanied by a significant upregulation of ONOO- and an increase of viscosity (or decrease of polarity) at the same time. Moreover, the concurrent use of ONOO-, viscosity, and polarity for the diagnosis of cancer has been successfully achieved not only at cell/tissue levels but also in tumor mice models. Compared with detecting only one factor, this simultaneous detection of multimarkers provides a more sensitive and reliable method/tool for tracking ferroptosis-related pathological processes and cancer diagnosis, holding great potential in preclinical research, medical diagnosis, and imaging-guided surgery.


Assuntos
Ferroptose , Neoplasias , Animais , Camundongos , Corantes Fluorescentes , Viscosidade , Ácido Peroxinitroso , Mitocôndrias , Neoplasias/diagnóstico por imagem
14.
Biol Reprod ; 108(5): 778-790, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-36857632

RESUMO

P450 aromatase, encoded by the Cyp19 gene, catalyzes the synthesis of estrogen, which is crucial for mammalian germ cell differentiation. We have previously shown that transforming growth factor beta 1 (TGF-ß1) attenuated the accumulation of steroidogenic factor-1 (SF-1) and liver receptor homolog-1 (LRH-1) and eventually reduced the transcription of Cyp19 in rat Leydig cells (LCs). Here, we report that TGF-ß1 treatment-induced phosphorylation of Smad2 and decreased the expression levels of SF-1 and LRH-1 by elevating the expression levels of microRNA-21-3p and microRNA-339-5p in vivo and in vitro. Furthermore, both TGF-ß1 treatment and over-expression of Smad2 inhibited the SF-1 or LRH-1-regulated promoter activity of the Cyp19 gene, and p-Smad2 physically interacted with SF-1 and LRH-1. Our findings collectively suggest that TGF-ß1 may inhibit the expression of CYP19 in LCs mainly through two ways. On the one hand, TGF-ß1 acts through Smad2 to repress the accumulation of SF-1 and LRH-1 at post-transcriptional level by upregulating specific microRNAs. On the other hand, TGF-ß1 inhibits the transcriptional activity of Cyp19 through the interaction of p-Smad2 with SF-1/LRH-1.


Assuntos
Aromatase , Células Intersticiais do Testículo , MicroRNAs , Proteína Smad2 , Fator de Crescimento Transformador beta1 , Animais , Masculino , Ratos , Aromatase/genética , Aromatase/metabolismo , Diferenciação Celular , Células Intersticiais do Testículo/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína Smad2/genética , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Fator de Crescimento Transformador beta1/metabolismo
15.
Haematologica ; 108(9): 2487-2502, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37021526

RESUMO

Enhancer of zeste homolog 2 (EZH2) is the lysine methyltransferase of polycomb repressive complex 2 (PRC2) that catalyzes H3K27 tri-methylation. Aberrant expression and loss-of-function mutations of EZH2 have been demonstrated to be tightly associated with the pathogenesis of various myeloid malignancies characterized by ineffective erythropoiesis, such as myelodysplastic syndrome (MDS). However, the function and mechanism of EZH2 in human erythropoiesis still remains largely unknown. Here, we demonstrated that EZH2 regulates human erythropoiesis in a stage-specific, dual-function manner by catalyzing histone and non-histone methylation. During the early erythropoiesis, EZH2 deficiency caused cell cycle arrest in the G1 phase, which impaired cell growth and differentiation. Chromatin immunoprecipitation sequencing and RNA sequencing discovered that EZH2 knockdown caused a reduction of H3K27me3 and upregulation of cell cycle proteindependent kinase inhibitors. In contrast, EZH2 deficiency led to the generation of abnormal nuclear cells and impaired enucleation during the terminal erythropoiesis. Interestingly, EZH2 deficiency downregulated the methylation of HSP70 by directly interacting with HSP70. RNA-sequencing analysis revealed that the expression of AURKB was significantly downregulated in response to EZH2 deficiency. Furthermore, treatment with an AURKB inhibitor and small hairpin RNAmediated AURKB knockdown also led to nuclear malformation and decreased enucleation efficiency. These findings strongly suggest that EZH2 regulates terminal erythropoiesis through a HSP70 methylation-AURKB axis. Our findings have implications for improved understanding of ineffective erythropoiesis with EZH2 dysfunction.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste , Eritropoese , Histonas , Humanos , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Eritropoese/genética , Histonas/metabolismo , Metilação , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo
16.
Chemistry ; 29(5): e202202896, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36326186

RESUMO

Two pairs of chiral end-on azido-bridged dinuclear hexaazamacrocycles, [Dy2 (LN6 R/S )2 (N3 )2 Cl2 ](BPh4 )2 (1R/1S) and [Dy2 (LN6 R/S )2 (N3 )4 ]Cl2 (2R/2S) (LN6 R/S is hexaazamacrocyclic neutral Schiff base ligand derived from 2,6-diformylpyridine and (1R, 2R)/(1S, 2S)-diaminocyclohexane), were constructed by adjusting the molar ratio of sodium azide to Dy(III) macrocycle precursor. Structural analyses reveal that all Dy(III) centers in complexes 1R/1S and 2R/2S are nine-coordinate with hula-loop coordination geometry, and the differences between 1R/1S and 2R/2S are the terminal coordination anion and counter anion. Magnetic studies indicate that complex 2S displays typical SMM behaviors under a zero dc field, whereas 1S just shows slow relaxation of magnetization resulting from a relatively weak axial crystal field. Significantly, complex 2R/2S represents the first homochiral all-nitrogen-coordinated lanthanide single-molecule magnet.


Assuntos
Elementos da Série dos Lantanídeos , Imãs , Disprósio , Nitrogênio
17.
Arch Biochem Biophys ; 748: 109766, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37813237

RESUMO

AIMS: FAM134B, the initial endoplasmic reticulum (ER)-phagy receptor identified, facilitates ER-phagy during ER stress. The malfunction of FAM134B has been demonstrated to have a crucial role in the pathological mechanisms of diverse human ailments. However, the role of FAM134B-mediated ER-phagy in ototoxicity, particularly in cisplatin-induced ototoxicity, remains unclear. The present study endeavors to investigate whether FAM134B is expressed in House Ear Institute-Organ of Corti 1 (HEI-OC1) and C57BL/6 murine cochlear hair cells (HCs), and to explore its potential function in cisplatin-mediated ototoxicity, with the aim of discovering new insights that can mitigate or forestall the irreversible adverse effect of cisplatin. METHODS: Immunofluorescence (IF) staining was used to test the expression pattern of FAM134B, levels of C/EBP-homologous protein (CHOP), autophagy, and co-localization ratio of lysosomes and ER. Western blotting was employed to measure changes in expression levels of FAM134B, LC3B, ER stress-related proteins, LAMP1 and apoptotic mediators. Cell apoptosis was examined using transferase dUTP nick end labeling (TUNEL) assay and flow cytometry. RESULTS: In the present investigation, it was observed that FAM134B exhibited a diffuse expression pattern in the cytoplasm and nuclei of control HEI-OC1 cells. Following cisplatin administration, FAM134B was found to accumulate and form distinct dots around the nuclei, concomitant with increased levels of ER-phagy, ER stress, unfolded protein response (UPR), and cell apoptosis. Additionally, knockdown of FAM134B resulted in reduced ER-phagy, mitigated ER stress and UPR, and decreased apoptotic activity in HEI-OC1 cells following cisplatin exposure. CONCLUSIONS: Collectively, the findings of this study demonstrate that FAM134B-mediated ER-phagy enhances the susceptibility of HCs to ER stress and apoptosis in response to cisplatin-induced stress. This suggests a sequential progression of ER-phagy, ER stress and apoptosis following cisplatin stimulus, and implies the potential therapeutic benefit of inhibiting of FAM134B-mediated ER-phagy in the prevention of cisplatin-related ototoxicity.


Assuntos
Cisplatino , Ototoxicidade , Camundongos , Humanos , Animais , Cisplatino/toxicidade , Ototoxicidade/metabolismo , Estresse do Retículo Endoplasmático , Células Ciliadas Auditivas/metabolismo , Autofagia , Retículo Endoplasmático/metabolismo , Apoptose
18.
J Org Chem ; 88(19): 13427-13439, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37750476

RESUMO

Herein, a series of chiral δ-lactam frameworks have been synthesized and catalyzed by chiral phosphoric acid (CPA) utilizing two kinds of open-chain aza-dienes and azlactones derived from amino acids. This powerful [4 + 2] annulation produces a broad substrate scope with functional group tolerance in yield up to 97% with up to 98:2 er. Moreover, a facile scale-up and straightforward conversion to diversely substituted products verify the synthetic utility of this method featuring good compatibility and high efficiency.

19.
Inorg Chem ; 62(39): 15943-15951, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37721404

RESUMO

Until now, effective blue light-emitting materials are essentially needed for the creation of white light and precise color renderings in real-world applications, but the efficiency of blue light-emitting materials has lagged far behind. Here, we present a hydrothermal method to synthesize tin-based metal halide single crystals (RbCdCl3:Sn2+ and Rb3SnCl7). Two single crystal materials with different shapes and phases can simultaneously be synthesized in the same stoichiometric ratio. Rb3SnCl7 has a bulk shape, while RbCdCl3:Sn2+ has a needle shape. The deep blue emission (436 nm) of RbCdCl3:Sn2+ can be obtained under the optimal excitation wavelength irradiation. However, pure blue emission (460 nm) to white light can be obtained by changing the excitation wavelength in Rb3SnCl7. The refinement spectra of the electronic structures of RbCdCl3:Sn2+ and Rb3SnCl7 are investigated by density functional theory. It is concluded that the difference in the distribution of Cl energy states leads to the existence of Cl local defect states, which is the reason for the rich luminescence of the two single crystals. These findings provide a path for realizing single-phase broadband white-emitting materials.

20.
J Chem Inf Model ; 63(5): 1626-1636, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36802582

RESUMO

Drug-drug interactions (DDIs) are a major concern in clinical practice and have been recognized as one of the key threats to public health. To address such a critical threat, many studies have been conducted to clarify the mechanism underlying each DDI, based on which alternative therapeutic strategies are successfully proposed. Moreover, artificial intelligence-based models for predicting DDIs, especially multilabel classification models, are highly dependent on a reliable DDI data set with clear mechanistic information. These successes highlight the imminent necessity to have a platform providing mechanistic clarifications for a large number of existing DDIs. However, no such platform is available yet. In this study, a platform entitled "MecDDI" was therefore introduced to systematically clarify the mechanisms underlying the existing DDIs. This platform is unique in (a) clarifying the mechanisms underlying over 1,78,000 DDIs by explicit descriptions and graphic illustrations and (b) providing a systematic classification for all collected DDIs based on the clarified mechanisms. Due to the long-lasting threats of DDIs to public health, MecDDI could offer medical scientists a clear clarification of DDI mechanisms, support healthcare professionals to identify alternative therapeutics, and prepare data for algorithm scientists to predict new DDIs. MecDDI is now expected as an indispensable complement to the available pharmaceutical platforms and is freely accessible at: https://idrblab.org/mecddi/.


Assuntos
Algoritmos , Inteligência Artificial , Humanos , Interações Medicamentosas
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