Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 355
Filter
Add more filters

Country/Region as subject
Publication year range
1.
Mol Cell ; 81(21): 4493-4508.e9, 2021 11 04.
Article in English | MEDLINE | ID: mdl-34555354

ABSTRACT

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.


Subject(s)
Eukaryotic Initiation Factor-4F/chemistry , Eukaryotic Initiation Factor-4G/metabolism , Hematologic Neoplasms/metabolism , Peptides/chemistry , Protein Biosynthesis , Animals , Disease Progression , Genome, Human , HEK293 Cells , Humans , Male , Mice , Mice, Inbred NOD , Mice, SCID , Open Reading Frames , Polyribosomes/chemistry , RNA, Messenger/metabolism , RNA, Untranslated/metabolism , RNA-Binding Proteins/genetics , Ribosomes/metabolism , Sensitivity and Specificity , Treatment Outcome
2.
Nucleic Acids Res ; 52(11): 6360-6375, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38682589

ABSTRACT

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.


Subject(s)
DNA Breaks, Double-Stranded , DNA Repair , DNA-Activated Protein Kinase , Ku Autoantigen , RNA Precursors , DNA-Activated Protein Kinase/metabolism , DNA-Activated Protein Kinase/genetics , Humans , RNA Precursors/metabolism , RNA Precursors/genetics , Cell Line, Tumor , Ku Autoantigen/metabolism , Ku Autoantigen/genetics , Phosphorylation , Cell Nucleolus/metabolism , Cell Nucleolus/genetics , Cell Nucleolus/drug effects , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , BRCA1 Protein/genetics , BRCA1 Protein/metabolism , RNA, Ribosomal/metabolism , RNA, Ribosomal/genetics , Animals , Ribosomal Proteins/genetics , Ribosomal Proteins/metabolism
3.
Med Res Rev ; 44(5): 1971-2014, 2024 09.
Article in English | MEDLINE | ID: mdl-38515232

ABSTRACT

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.


Subject(s)
Drug Design , Drug Discovery , Stereoisomerism , Humans , Animals
4.
J Am Chem Soc ; 146(6): 3764-3772, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38304977

ABSTRACT

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.
Anal Chem ; 2024 Sep 27.
Article in English | MEDLINE | ID: mdl-39331475

ABSTRACT

Generally, rolling circle amplification (RCA) is based on an enzyme-linked padlock extension reaction. Herein, rapid linking that utilizes click chemistry for joining sticky ends of DNA molecules was developed. The ends of nucleic acid were modified with 2-cyano-6-aminobenzothiazole (CBT) and cystine (Cys-Cys), while glutathione was introduced to break the disulfide bond under target navigation and promote the linkage between CBT and Cys at the terminus of the nucleic acid at pH 7.4. Subsequently, RCA was performed using phi29 polymerase. CRISPR/Cas12a cleavage was triggered by the product of RCA amplification. Assisted by alkaline phosphatase, the electron exchange process between the photoelectroactive Sb@Co(OH)F nanorod and p-aminophenol (p-AP) was collected in the form of photoelectrochemical (PEC) signals. Mass spectrometry, gel electrophoresis, and PEC signals were employed to verify the linking process and the RCA coupled with CRISPR/Cas12a cleavage amplification. CBT-Cys connection exhibited a high reaction rate (23.79 M-1·s-1). This enzyme-free linking process was superior to traditional enzyme catalysis in terms of the reaction environment and linking rate. This efficient nonenzymatic joining system holds great potential for constructing nonhomologous end joining, modifying DNA with molecules, and facilitating nucleic acid-protein modification processes.

6.
FASEB J ; 37(11): e23265, 2023 11.
Article in English | MEDLINE | ID: mdl-37874273

ABSTRACT

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.


Subject(s)
Podocytes , Proteolysis , Animals , Mice , GTP Phosphohydrolases/genetics , GTP Phosphohydrolases/metabolism , Metalloproteases/genetics , Metalloproteases/metabolism , Mitochondrial Dynamics , Mitochondrial Proteins/metabolism , Podocytes/metabolism , Proteinuria/metabolism , Uncoupling Protein 2/genetics , Uncoupling Protein 2/metabolism
7.
Virol J ; 21(1): 212, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39252096

ABSTRACT

BACKGROUND: Patients treated with anti-CD20 monoclonal antibodies could have a higher risk of adverse outcomes of coronavirus disease 2019 (COVID-19). The novel anti-CD20 monoclonal antibody obinutuzumab has shown greater B-cell depletion and superior in vitro efficacy than rituximab. We aimed to assess whether obinutuzumab would result in worse COVID-19 outcomes than rituximab. METHODS: We retrospectively reviewed 124 patients with B-cell lymphoma, 106 of whom received rituximab treatment and 18 of whom received obinutuzumab treatment. The adverse outcomes of COVID-19 were compared between patients in the two cohorts. RESULTS: The proportions of patients who were hospitalized (55.6% vs. 20.8%, p = 0.005), experienced prolonged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (38.9% vs. 2.9%, p < 0.001), and developed severe COVID-19 (33.3% vs. 4.7%, p < 0.001) were higher in patients with obinutuzumab than in those with rituximab. Multivariate analyses showed that obinuzumab treatment was associated with higher incidences of prolonged SARS-CoV-2 infection (OR 27.05, 95% CI 3.75-195.22, p = 0.001) and severe COVID-19(OR 15.07, 95% CI 2.58-91.72, p = 0.003). CONCLUSIONS: Our study suggested that patients treated with obinutuzumab had a higher risk of prolonged SARS-CoV-2 infection and severe COVID-19 than those treated with rituximab.


Subject(s)
Antibodies, Monoclonal, Humanized , COVID-19 , Rituximab , SARS-CoV-2 , Humans , Rituximab/therapeutic use , Rituximab/adverse effects , Antibodies, Monoclonal, Humanized/therapeutic use , Antibodies, Monoclonal, Humanized/adverse effects , Retrospective Studies , Male , Female , Middle Aged , Aged , SARS-CoV-2/drug effects , COVID-19 Drug Treatment , Treatment Outcome , Adult , Lymphoma, B-Cell/drug therapy , Hospitalization/statistics & numerical data , Aged, 80 and over
8.
BMC Public Health ; 24(1): 1367, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38773446

ABSTRACT

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.


Subject(s)
Hypertension, Pregnancy-Induced , Screen Time , Humans , Female , Pregnancy , Retrospective Studies , Adult , Hypertension, Pregnancy-Induced/epidemiology , China/epidemiology , Smartphone/statistics & numerical data , Television/statistics & numerical data , Risk Factors , Incidence , Young Adult , Time Factors
9.
Reprod Health ; 21(1): 127, 2024 Sep 02.
Article in English | MEDLINE | ID: mdl-39223548

ABSTRACT

BACKGROUND: Previous studies indicated that excessive engagement in digital devices could lead to negative psychological impacts in general population. We aimed to determine the association of electronic screen exposure with depression among women in early pregnancy. METHODS: A cross-sectional study was conducted from June 2021 to June 2022. A total of 665 women in early pregnancy were recruited and the information included socio-demographic characteristics, screen exposure and Patient Health Questionnaire - 9 depression scale. RESULTS: Among the women in early pregnancy, the total daily smartphone viewing time was the longest (median [P25-P75], 5 [3-6] hours/day) in the three types of electronic screen exposure. The total daily smartphone viewing time (P = 0.015, OR[95%CI] = 1.09[1.11-1.18]), smartphone (P = 0.016, OR[95%CI] = 1.24[1.04-1.47]) and television viewing time (P = 0.006, OR[95%CI] = 1.35[1.09-1.67]) before nocturnal sleep were significantly associated with depression among women in early pregnancy. The thresholds calculated by receiver operator characteristic curves were 7.5 h/day, 1.5 h/day and 1.5 h/day, respectively. In addition, women with higher scores of smartphone addiction were more susceptible to depression (P<0.001, OR[95%CI] = 1.11[1.07-1.16]). The top three smartphone usages in women with depression were watching videos (22.0%), listening to music (20.9%) and playing games (16.7%). CONCLUSIONS: In conclusion, electronic screen exposure, including screen viewing time, smartphone addiction and problematic smartphone use was associated with depression among women in early pregnancy. Further studies are warranted to verify the conclusions.


Subject(s)
Depression , Screen Time , Smartphone , Humans , Female , Pregnancy , Cross-Sectional Studies , Adult , Depression/etiology , Young Adult , Pregnancy Complications/psychology , Television
10.
Nano Lett ; 23(23): 11314-11322, 2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38018816

ABSTRACT

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.

11.
Psychol Health Med ; 29(9): 1583-1601, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38503424

ABSTRACT

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.


Subject(s)
Depression , Sleep Quality , Students , Suicidal Ideation , Humans , Students/psychology , Students/statistics & numerical data , Male , Female , Depression/psychology , Depression/epidemiology , Young Adult , Universities , Adult , Sleep Wake Disorders/psychology , Sleep Wake Disorders/epidemiology , Adolescent , Surveys and Questionnaires
12.
Int J Mol Sci ; 25(4)2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38396956

ABSTRACT

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.


Subject(s)
Acanthaceae , Genome, Mitochondrial , Animals , Phylogeny , Genome, Mitochondrial/genetics , Snails/genetics , RNA, Ribosomal/genetics , RNA, Transfer/genetics
13.
Aust Crit Care ; 2024 May 17.
Article in English | MEDLINE | ID: mdl-38762342

ABSTRACT

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.

14.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(1): 190-197, 2024 Jan 20.
Article in Zh | MEDLINE | ID: mdl-38322514

ABSTRACT

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.


Subject(s)
Chitosan , Hemostatics , Zein , Animals , Rabbits , Chitosan/chemistry , Hemostatics/pharmacology , Escherichia coli , Glycerol/pharmacology , Staphylococcus aureus , Zein/pharmacology , Hemostasis , Anti-Bacterial Agents/pharmacology , Hemorrhage , Water/pharmacology , Ethylamines/pharmacology , Phenols/pharmacology
15.
Angew Chem Int Ed Engl ; 63(5): e202312663, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38032817

ABSTRACT

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.


Subject(s)
Azo Compounds , Imines , Thiosemicarbazones , Stereoisomerism , Azo Compounds/pharmacology , Catalysis
16.
Anal Chem ; 95(13): 5780-5787, 2023 04 04.
Article in English | MEDLINE | ID: mdl-36939176

ABSTRACT

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.


Subject(s)
Ferroptosis , Neoplasms , Animals , Mice , Fluorescent Dyes , Viscosity , Peroxynitrous Acid , Mitochondria , Neoplasms/diagnostic imaging
17.
Biol Reprod ; 108(5): 778-790, 2023 05 10.
Article in English | MEDLINE | ID: mdl-36857632

ABSTRACT

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.


Subject(s)
Aromatase , Leydig Cells , MicroRNAs , Smad2 Protein , Transforming Growth Factor beta1 , Animals , Male , Rats , Aromatase/genetics , Aromatase/metabolism , Cell Differentiation , Leydig Cells/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Smad2 Protein/genetics , Smad2 Protein/metabolism , Transforming Growth Factor beta1/pharmacology , Transforming Growth Factor beta1/metabolism
18.
Haematologica ; 108(9): 2487-2502, 2023 09 01.
Article in English | MEDLINE | ID: mdl-37021526

ABSTRACT

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.


Subject(s)
Enhancer of Zeste Homolog 2 Protein , Erythropoiesis , Histones , Humans , Enhancer of Zeste Homolog 2 Protein/genetics , Erythropoiesis/genetics , Histones/metabolism , Methylation , Polycomb Repressive Complex 2/genetics , Polycomb Repressive Complex 2/metabolism
19.
Chemistry ; 29(5): e202202896, 2023 Jan 24.
Article in English | MEDLINE | ID: mdl-36326186

ABSTRACT

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.


Subject(s)
Lanthanoid Series Elements , Magnets , Dysprosium , Nitrogen
20.
Arch Biochem Biophys ; 748: 109766, 2023 10 15.
Article in English | MEDLINE | ID: mdl-37813237

ABSTRACT

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.


Subject(s)
Cisplatin , Ototoxicity , Mice , Humans , Animals , Cisplatin/toxicity , Ototoxicity/metabolism , Endoplasmic Reticulum Stress , Hair Cells, Auditory/metabolism , Autophagy , Endoplasmic Reticulum/metabolism , Apoptosis
SELECTION OF CITATIONS
SEARCH DETAIL