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1.
MedComm (2020) ; 5(10): e705, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39309689

RESUMO

The metabolic enzyme methionine adenosyltransferase 2A (MAT2A) was found to elicit synthetic lethality in methylthioadenosine phosphorylase (MTAP)-deleted cancers, which occur in about 15% of all cancers. Here, we described a novel MAT2A inhibitor, SCR-7952 with potent and selective antitumor effects on MTAP-deleted cancers in both in vitro and in vivo. The cryo-EM data indicated the high binding affinity and the allosteric binding site of SCR-7952 on MAT2A. Different from AG-270, SCR-7952 exhibited little influence on metabolic enzymes and did not increase the plasma levels of bilirubin. A systematic evaluation of combination between SCR-7952 and different types of protein arginine methyltransferase 5 (PRMT5) inhibitors indicated remarkable synergistic interactions between SCR-7952 and the S-adenosylmethionine-competitive or the methylthioadenosine-cooperative PRMT5 inhibitors, but not substrate-competitive ones. The mechanism was via the aggravated inhibition of PRMT5 and FANCA splicing perturbations. These results indicated that SCR-7952 could be a potential therapeutic candidate for the treatment of MTAP-deleted cancers, both monotherapy and in combination with PRMT5 inhibitors.

2.
3.
Cell Signal ; : 111425, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39307376

RESUMO

Clear cell renal cell carcinoma (ccRCC) is a malignant tumor needs more effective treatments. TATA box-binding protein-associated factor RNA polymerase I subunit D (TAF1D) is a member of the selective factor 1 complex and functions in RNA polymerase I-dependent transcription. Higher TAF1D expression was found in ccRCC tumor tissues and indicated worse survival. Our study aimed to investigate the therapeutic potential of TAF1D in ccRCC. The proliferation and migration of ccRCC cells were significantly inhibited after TAF1D knockdown, while TAF1D overexpressing had opposite effects. Moreover, TAF1D knockdown induced cells to undergo G0/G1 cell cycle arrest and blockade of the epithelial-mesenchymal transition (EMT) process. Mechanistically, TAF1D affect the cell cycle and EMT through the PI3K/AKT/mTOR signaling pathway, thereby promoting the proliferation and metastasis of ccRCC cells in vivo and in vitro. The inhibitory effect of TAF1D knockdown could be reverted by the AKT activator SC79 in ccRCC cells, confirming this mechanism. Besides, TAF1D knockdown in ccRCC cells had a sensitizing effect on sunitinib and enhanced tumor cell inhibiting induced by sunitinib. In conclusion, TAF1D may be a promising target for the treatment of ccRCC and for overcoming sunitinib resistance.

4.
Cells ; 13(17)2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39272995

RESUMO

Epidemiological, experimental, and ecological data have indicated the controversial effect of in utero chronic low dose rate (<6 mGy/h) with accumulative low (≤100 mGy) or high (>100 mGy) dose radiation exposure. Our main goal of this study was to examine if different low dose rates of chronic pre- and/or post-natal radiation exposure with accumulative high doses could induce hippocampal cellular, mRNA, and miRNA changes leading to neuropsychiatric disorders. The comprehensive mouse phenotypic traits, organ weight, pathological, and blood mRNA and miRNA changes were also studied. Using different approaches including SmithKline, Harwell, Imperial College, Royal Hospital, Phenotype Assessment (SHIRPA), neurobehavioral tests, pathological examination, immunohistochemistry, mRNA and miRNA sequencing, and real-time quantitative polymerase chain reaction (qRT-PCR) validation, we found that in prenatally irradiated (100 mGy/d for 18 days with an accumulative dose of 1.8 Gy) 1-year-old mice, no cellular changes, including immature neurons in the subgranular zone, mature neurons and glial cells in the hilus of the dentate gyrus and development of cognitive impairment, neuropsychiatric disorders, occurred. However, a significant reduction in body weight and mass index (BMI) was indicated by the SHIRPA test. A reduced exploratory behavior was shown by an open field test. Organ weights showed significant reductions in the testes, kidneys, heart, liver and epididymides with no abnormal pathology. mRNA and miRNA sequencing and qRT-PCR validation revealed the upregulation of Rubcnl and Abhd14b, and downregulation of Hspa1b, P4ha1, and Banp genes in both the hippocampus and blood of mice prenatally irradiated with 100 mGy/d. Meanwhile, downregulation of miR-448-3p and miR1298-5p in the hippocampus, miR-320-3p, miR-423-5p, miR-486b-5p, miR-486b-3p, miR-423-3p, miR-652-3p, miR-324-3p, miR-181b-5p, miR-let-7b, and miR-6904-5p in the blood was induced. The target scan revealed that Rubcnl is one of the miR-181b-5p targets in the blood. We, therefore, concluded that prenatal chronic irradiation with a low dose rate of 100 mGy/d and accumulative dose of 1.8 Gy or below might not induce significant adverse health effects on the offspring. Further study of different low dose rate radiation exposures with accumulative high doses may provide threshold doses for authorities or regulators to set new radiation safety guidelines to replace those extrapolated from acute high dose/dose rate irradiation to reduce unnecessary emergency evacuation or spending once a nuclear accident or leakage occurs.


Assuntos
Hipocampo , MicroRNAs , Efeitos Tardios da Exposição Pré-Natal , RNA Mensageiro , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Camundongos , Hipocampo/efeitos da radiação , Hipocampo/metabolismo , Hipocampo/patologia , Feminino , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Efeitos Tardios da Exposição Pré-Natal/genética , Masculino , Comportamento Animal/efeitos da radiação , Relação Dose-Resposta à Radiação , Tamanho do Órgão/efeitos da radiação
5.
Microbiol Spectr ; : e0034124, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248524

RESUMO

The plasmid-mediated gene mcr-1 that makes bacteria resistant to the antibiotic colistin is spreading quickly, which means that colistin is no longer working well to treat Gram-negative bacterial infections. Herein, we utilized a computer-aided high-throughput screening drugs method to identify the natural product apigenin, a potential mcr-protein inhibitor, which effectively enhanced the antimicrobial activity of colistin. Several assays, including a checkerboard minimum inhibitory concentration assay, a time-kill assay, the combined disk test, molecular simulation dynamics, and animal infection models assay, were conducted to verify whether apigenin enhanced the ability of colistin to fight Gram-negative bacterial infections. The results showed that apigenin improved the antimicrobial activity of colistin against multidrug-resistant Enterobacteriaceae infection. Moreover, apigenin not only did not increase the toxic effect of colistin but also had the ability to effectively inhibit the frequency of bacterial resistance mutations to colistin. Studies clearly elucidated that apigenin could interfere with the thermal stability of the protein by binding to the mcr-1 protein. Additionally, the combination of apigenin and colistin could exert multiple effects, including disrupting bacterial membranes, the generation of bacterial nitric oxide and reactive oxygen species, as well as inhibiting bacterial adenosine triphosphate production. Furthermore, the addition of apigenin was able to significantly inhibit colistin-stimulated high expression levels of the bacterial mcr-1 gene. Finally, apigenin exhibited a characteristic anti-inflammatory effect while enhancing the antimicrobial activity of colistin against mcr-1-positive Escherichia coli (E. coli) infected animals. In conclusion, as a potential lead compound, apigenin is promising in combination with colistin in the future treatment of mcr-1-positive E. coli infections.IMPORTANCEThis study found that apigenin was able to inhibit the activity of the mcr-1 protein using a high-throughput virtual screening method. Apigenin effectively enhanced the antimicrobial activity of colistin against multidrug-resistant Enterobacteriaceae, including mcr-1-positive strains, in vitro and in vivo. This study will provide new options and strategies for the future treatment of multidrug-resistant pathogen infections.

6.
PLoS One ; 19(8): e0308168, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39110703

RESUMO

The ovarian KGN granulosa-like tumour cell line is commonly used as a model for human granulosa cells, especially since it produces steroid hormones. To explore this further, we identified genes that were differentially expressed by KGN cells compared to primary human granulosa cells using three public RNA sequence datasets. Of significance, we identified that the expression of the antioxidant gene TXNRD1 (thioredoxin reductase 1) was extremely high in KGN cells. This is ominous since cytochrome P450 enzymes leak electrons and produce reactive oxygen species during the biosynthesis of steroid hormones. Gene Ontology (GO) analysis identified steroid biosynthetic and cholesterol metabolic processes were more active in primary granulosa cells, whilst in KGN cells, DNA processing, chromosome segregation and kinetochore pathways were more prominent. Expression of cytochrome P450 cholesterol side-chain cleavage (CYP11A1) and cytochrome P450 aromatase (CYP19A1), which are important for the biosynthesis of the steroid hormones progesterone and oestrogen, plus their electron transport chain members (FDXR, FDX1, POR) were measured in cultured KGN cells. KGN cells were treated with 1 mM dibutyryl cAMP (dbcAMP) or 10 µM forskolin, with or without siRNA knockdown of TXNRD1. We also examined expression of antioxidant genes, H2O2 production by Amplex Red assay and DNA damage by γH2Ax staining. Significant increases in CYP11A1 and CYP19A1 were observed by either dbcAMP or forskolin treatments. However, no significant changes in H2O2 levels or DNA damage were found. Knockdown of expression of TXNRD1 by siRNA blocked the stimulation of expression of CYP11A1 and CYP19A1 by dbcAMP. Thus, with TXNRD1 playing such a pivotal role in steroidogenesis in the KGN cells and it being so highly overexpressed, we conclude that KGN cells might not be the most appropriate model of primary granulosa cells for studying the interplay between ovarian steroidogenesis, reactive oxygen species and antioxidants.


Assuntos
Antioxidantes , Aromatase , Enzima de Clivagem da Cadeia Lateral do Colesterol , Células da Granulosa , Humanos , Feminino , Antioxidantes/metabolismo , Aromatase/genética , Aromatase/metabolismo , Linhagem Celular Tumoral , Células da Granulosa/metabolismo , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Tiorredoxina Redutase 1/metabolismo , Tiorredoxina Redutase 1/genética , Regulação Neoplásica da Expressão Gênica , Tumor de Células da Granulosa/genética , Tumor de Células da Granulosa/metabolismo , Tumor de Células da Granulosa/patologia , Esteroides/biossíntese , Progesterona/metabolismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia
7.
ChemSusChem ; : e202401207, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101598

RESUMO

The interactions between the electron donors and electron acceptors (D/A) play important roles for the performance of organic solar cells (OSCs). While the isomerization strategy is known to optimize molecular geometries and properties, the impacts of isomerization on the donors or acceptors in D/A interactions have not been extensively investigated. Here in, we innovatively investigated the impacts of donor isomerism on the D/A interactions by synthesizing two small molecule donors m-ph-ZnP2 and p-ph-ZnP2 by linking two functionalized porphyrins at the meta and para positions of phenyl groups, respectively. Compared with p-ph-ZnP2, m-ph-ZnP2 displays reduced self-aggregation but  with PC61BM. Consequently, a much higher power conversion efficiency (PCE) of 5.43% is achieved for the m-ph-ZnP2 binary OSCs than the p-ph-ZnP2 devices with a PCE of 2.03%. The enhanced performance of m-ph-ZnP2-based device can be primarily attributed to the stronger intramolecular charge transfer (ICT), the enhanced D/A interactions, the improved charge transfer, and the suppressed charge recombination. Furthermore, the ternary devices based on m-ph-ZnP2:Y6:PC61BM achieve a PCE of 8.34%. In short, this work elucidates the relationship among the chemical structure, D/A interactions and device performance, providing valuable guidelines for designing efficient OSCs materials.

8.
Radiat Res ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39164012

RESUMO

The radiosensitivity of mice differs between postnatal days 10 (P10) and 21(P21); these days mark different stages of brain development. In the present study, Ki67 and doublecotin (DCX) immunostaining and hematoxylin staining was performed, which showed that acute radiation exposure at postnatal day 10 induced higher cell apoptosis and loss in the hilus of the dentate gyrus at day 1 postirradiation than postnatal day 21. MicroRNA (miRNA) sequencing and real-time quantitative reverse transcription PCR (qRT-PCR) analysis indicated the upregulation of miRNA-34a-5p at days 1 and 7 days after irradiation at postnatal day 10, but not at postnatal day 21. Down-regulation of T-cell intracytoplasmic antigen-1 pathway (Tia1) was indicated by qRT-PCR at day 1 day but not day 7 after irradiation at postnatal day 10. Neurobehavioral testing in mature mice irradiated at postnatal day 10 demonstrated the impairment of short-term memory in novel object recognition and spatial memory, compared to those irradiated at postnatal day 21. Combined with our previous luciferase assay showing the direct interaction of miRNA34a-5p and Tia1, these findings suggest that radiation-induced abnormal miR-34a-5p/Tial interaction at day 1 after irradiation at postnatal day 10 may be involved in apoptosis of the dentate gyrus hilar, impairment of neurogenesis and subsequent short-term memory loss as observed in the novel object recognition and Barnes maze tests.

9.
PLoS One ; 19(8): e0305893, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39121087

RESUMO

During maturation oocytes at the germinal vesicle (GV) stage progress to metaphase II (MII). However, during in vitro maturation a proportion often fail to progress. To understand these processes, we employed RNA sequencing to examine the transcriptome profile of these three groups of oocytes from the pig. We compared our findings with similar public oocyte data from humans. The transcriptomes in oocytes that failed to progress was similar to those that did. We found in both species, the most upregulated genes in MII oocytes were associated with chromosome segregation and cell cycle processes, while the most down regulated genes were relevant to ribosomal and mitochondrial pathways. Moreover, those genes involved in chromosome segregation during GV to MII transition were conserved in pig and human. We also compared MII and GV oocyte transcriptomes at the isoform transcript level in both species. Several thousands of genes (including DTNBP1, MAPK1, RAB35, GOLGA7, ATP1A1 and ATP2B1) identified as not different in expression at a gene transcript level were found to have differences in isoform transcript levels. Many of these genes were involved in ATPase-dependent or GTPase-dependent intracellular transport in pig and human, respectively. In conclusion, our study suggests the failure to progress to MII in vitro may not be regulated at the level of the genome and that many genes are differentially regulated at the isoform level, particular those involved ATPase- or GTPase-dependent intracellular transport.


Assuntos
Metáfase , Oócitos , Humanos , Oócitos/metabolismo , Oócitos/citologia , Animais , Suínos , Feminino , Transcriptoma , Análise de Sequência de RNA , Oogênese/genética , Perfilação da Expressão Gênica
10.
J Am Chem Soc ; 146(34): 23752-23763, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39143892

RESUMO

A reversible modification strategy enables a switchable cage/decage process of proteins with an array of applications for protein function research. However, general N-terminal selective reversible modification strategies which present site selectivity are specifically limited. Herein, we report a general reversible modification strategy compatible with 20 canonical amino acids at the N-terminal site by the palladium-catalyzed cinnamylation of native peptides and proteins under biologically relevant conditions. This approach broadens the substrate adaptability of N-terminal modification of proteins and shows a potential impact on the more challenging protein substrates such as antibodies. In the presence of 1,3-dimethylbarbituric acid, palladium-catalyzed deconjugation released native peptides and proteins efficiently. Harnessing the reversible nature of this protocol, practical applications were demonstrated by precise function modulation of antibodies and traceless enrichment of the protein-of-interest for proteomics analysis. This novel on/off strategy working on the N-terminus will provide new opportunities in chemical biology and medicinal research.


Assuntos
Peptídeos , Proteínas , Peptídeos/química , Proteínas/química , Paládio/química , Catálise
11.
J Am Chem Soc ; 146(32): 22553-22562, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39101269

RESUMO

N2-Alkyl-2'-deoxyguanosine (N2-alkyl-dG) is a major type of minor-groove DNA lesions arising from endogenous metabolic processes and exogenous exposure to environmental contaminants. The N2-alkyl-dG lesions, if left unrepaired, can block DNA replication and transcription and induce mutations in these processes. Nevertheless, the repair pathways for N2-alkyl-dG lesions remain incompletely elucidated. By utilizing a photo-cross-linking coupled with mass spectrometry-based quantitative proteomic analysis, we identified a series of candidate N2-alkyl-dG-binding proteins. We found that two of these proteins, i.e., high-mobility group protein B3 (HMGB3) and SUB1, could bind directly to N2-nBu-dG-containing duplex DNA in vitro and promote the repair of this lesion in cultured human cells. In addition, HMGB3 and SUB1 protected cells against benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE). SUB1 exhibits preferential binding to both the cis and trans diastereomers of N2-BPDE-dG over unmodified dG. On the other hand, HMGB3 binds favorably to trans-N2-BPDE-dG; the protein, however, does not distinguish cis-N2-BPDE-dG from unmodified dG. Consistently, genetic ablation of HMGB3 conferred diminished repair of trans-N2-BPDE-dG, but not its cis counterpart, whereas loss of SUB1 conferred attenuated repair of both diastereomers. Together, we identified proteins involved in the cellular sensing and repair of minor-groove N2-alkyl-dG lesions and documented a unique role of HMGB3 in the stereospecific recognition and repair of N2-BPDE-dG.


Assuntos
Reparo do DNA , DNA , Proteína HMGB3 , Humanos , DNA/química , DNA/metabolismo , Dano ao DNA , Enzimas Reparadoras do DNA , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/química , Guanina/química , Guanina/metabolismo , Proteína HMGB3/metabolismo , Proteína HMGB3/química , Ligação Proteica
12.
Fish Shellfish Immunol ; 153: 109834, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39151840

RESUMO

This experiment was conducted to explore the effects of dietary vitamin C supplementation on non-specific immune defense, antioxidant capacity and resistance to low-temperature stress of juvenile mud crab (Scylla paramamosain). Mud crabs with an initial weight of 14.67 ± 0.13 g were randomly divided into 6 treatments and fed diets with 0.86 (control), 44.79, 98.45, 133.94, 186.36 and 364.28 mg/kg vitamin C, respectively. The experiment consisted of 6 treatments, each treatment was designed with 4 replicates and each replicate was stocked with 8 crabs. After 42 days of feeding experiment, 2 crabs were randomly selected from each replicate, and a total of 8 crabs in each treatment were carried out 72 h low-temperature challenge experiment. The results showed that crabs fed diets with 186.36 and 364.28 mg/kg vitamin C significantly improved the activities of alkaline phosphatase (AKP) and acid phosphatase (ACP) in hemolymph and hepatopancreas (P < 0.05). Crabs fed diet with 133.94 mg/kg vitamin C significantly decreased the concentration of nitric oxide (NO) and the activity of nitric oxide synthase (NOS) in hemolymph (P < 0.05). Diet with 133.94 mg/kg vitamin C was improved the activity of polyphenol oxidase (PPO) and the concentration of albumin (ALB) in hemolymph. Crabs fed diet with 133.94 mg/kg vitamin C showed lower concentration of malondialdehyde (MDA) in hemolymph and hepatopancreas than those fed the other diets. Meanwhile, crabs fed diet with 98.45 mg/kg vitamin C showed higher activity of total superoxide dismutase (T-SOD) in hemolymph, and crabs fed diet with 133.94 mg/kg vitamin C showed higher activity of T-SOD in hepatopancreas. Crabs fed diet with 186.36 mg/kg vitamin C significantly decreased the concentration of reduced glutathione (GSH) and the activity of glutathione peroxidase (GSH-PX) in hepatopancreas (P < 0.05). In normal temperature, crabs fed diets with 133.94 mg/kg vitamin C significantly up-regulated the expression levels of gpx (glutathione peroxidase) and trx (thioredoxin) in hepatopancreas compared with the control treatment (P < 0.05). The highest expression levels of relish, il16 (interleukin 16), caspase 2 (caspase 2), p38 mapk (p38 mitogen-activated protein kinases) and bax (bcl-2 associated x protein) in hepatopancreas were found at crabs fed control diet (P < 0.05). Moreover, crabs fed diet with 133.94 mg/kg vitamin C showed higher expression levels of alf-3 (anti-lipopolysaccharide factor 3) and bcl-2 (B-cell lymphoma 2) in hepatopancreas than those fed the other diets (P < 0.05). Under low-temperature stress, crabs fed diet with 133.94 mg/kg vitamin C significantly improved the expression levels of hsp90 (heat shock protein 90), cat (catalase), gpx, prx (thioredoxin peroxidase) and trx in hepatopancreas (P < 0.05). In addition, dietary with 133.94 vitamin C significantly up-regulated the expression levels of alf-3 and bcl-2 (P < 0.05). Based on two slope broken-line regression analysis of activity of PPO against the dietary vitamin C level, the optimal dietary vitamin C requirement was estimated to be 144.81 mg/kg for juvenile mud crab. In conclusion, dietary 133.94-144.81 mg/kg vitamin C significantly improved the non-specific immune defense, antioxidant capacity and resistance to low-temperature stress of juvenile mud crab.


Assuntos
Ração Animal , Antioxidantes , Ácido Ascórbico , Braquiúros , Temperatura Baixa , Dieta , Suplementos Nutricionais , Imunidade Inata , Animais , Braquiúros/imunologia , Braquiúros/efeitos dos fármacos , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/farmacologia , Ração Animal/análise , Dieta/veterinária , Imunidade Inata/efeitos dos fármacos , Suplementos Nutricionais/análise , Antioxidantes/metabolismo , Distribuição Aleatória , Estresse Fisiológico/efeitos dos fármacos , Relação Dose-Resposta a Droga
13.
Int Immunopharmacol ; 139: 112707, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39032472

RESUMO

Telmisartan, an angiotensin II type 1 receptor (AT1R) blocker, exhibits broad anti-tumor activity. However, in vitro, anti-proliferative effects are shown at doses far beyond the therapeutic plasma concentration. Considering the role of tumor microenvironment in glioma progression, glioma-astrocyte co-cultures were employed to test the anti-tumor potential of low-dose telmisartan. When a high dose was required for a direct anti-proliferative effect on glioma cell lines, a low dose significantly inhibited glioma cell proliferation and migration in the co-culture system. Under co-culture conditions, upregulated IL-6 expression in astrocytes played a critical role in glioma progression. Silencing IL-6 in astrocytes or IL-6R in glioma cells reduced proliferation and migration. Telmisartan (5 µM) inhibited astrocytic IL-6 expression, and its anti-tumor effects were reversed by silencing IL-6 or IL-6R and inhibiting signal transducer and activator of transcription 3 (STAT3) activity in glioma cells. Moreover, the telmisartan-driven IL-6 downregulation was not imitated by losartan, an AT1R blocker with little capacity of peroxisome proliferator-activated receptor-gamma (PPARγ) activation, but was eliminated by a PPARγ antagonist, indicating that the anti-glioma effects of telmisartan rely on its PPARγ agonistic activity rather than AT1R blockade. This study highlights the importance of astrocytic IL-6-mediated paracrine signaling in glioma growth and the potential of telmisartan as an adjuvant therapy for patients with glioma, especially those with hypertension.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II , Astrócitos , Proliferação de Células , Técnicas de Cocultura , Glioma , Interleucina-6 , PPAR gama , Fator de Transcrição STAT3 , Telmisartan , Telmisartan/farmacologia , Telmisartan/uso terapêutico , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Interleucina-6/metabolismo , Glioma/tratamento farmacológico , Glioma/metabolismo , Glioma/patologia , Humanos , Proliferação de Células/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Linhagem Celular Tumoral , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , PPAR gama/metabolismo , Comunicação Parácrina/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Receptores de Interleucina-6/metabolismo , Losartan/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Microambiente Tumoral/efeitos dos fármacos
14.
Reprod Fertil ; 5(3)2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38990713

RESUMO

Abstract: Reactive oxygen species (ROS) are a by-product of the activity of cytochrome P450 steroidogenic enzymes. Antioxidant enzymes protect against ROS damage. To identify if any particular antioxidant enzyme is used to protect against ROS produced by granulosa cells as follicles enlarge and produce oestradiol, we measured in the bovine granulosa cells the expression of two steroidogenic enzymes (CYP11A1, CYP19A1), important for progesterone and oestradiol production. We also measured the expression of the members (FDXR, FDX1, POR) of their electron transport chains (ETC). We measured antioxidant enzymes (GPXs 1-8, CAT, SODs 1 and 2, PRDXs 1-6, GSR, TXN, TXNRDs 1-3). Since selenium is an active component of GPXs, the selenium-uptake receptors (LRPs 2 and 8) were measured. Only the selenium-dependent GPX1 showed the same increase in expression as the steroidogenic enzymes did with increasing follicle size. GPX4 and PRDX2/6 decreased with follicle size, whereas SOD1/2, CAT, GSR, and TXNRD3 were lowest at the intermediate sizes. The other antioxidant enzymes were unchanged or expressed at low levels. The expression of the selenium-uptake receptor LRP8 also increased significantly with follicle size. Correlation analysis revealed statistically significant and strongly positive correlations of the steroidogenic enzymes and their ETCs with both GPX1 and LRP8. These results demonstrate a relationship between the expression of genes involved in steroidogenesis and selenium-containing antioxidant defence mechanisms. They suggest that during the late stages of folliculogenesis, granulosa cells are dependent on sufficient expression of GPX1 and the selenium transporter LRP8 to counteract increasing ROS levels caused by the production of steroid hormones. Lay summary: In the ovary, eggs are housed in follicles which contain the cells that produce oestrogen in the days leading up to ovulation of the egg. Oestrogen is produced by the action of enzymes. However, some of these enzymes also produce by-products called reactive oxygen species (ROS). These are harmful to eggs. Fortunately, cells have protective antioxidant enzymes that can neutralise ROS. This study was interested in which particular antioxidant enzyme(s) might be involved in neutralising the ROS in follicle cells. It was found that only one antioxidant enzyme, GPX1, appeared to be co-regulated with the enzymes that produce oestrogen and progesterone in the follicular cells. GPX1 contains the essential mineral selenium. In summary, this study has identified which antioxidant appears to be involved in neutralising ROS in the days leading to ovulation. It highlights the importance of selenium in the diet.


Assuntos
Glutationa Peroxidase GPX1 , Glutationa Peroxidase , Células da Granulosa , Feminino , Células da Granulosa/metabolismo , Animais , Bovinos , Glutationa Peroxidase/metabolismo , Glutationa Peroxidase/genética , Selênio/metabolismo , Antioxidantes/metabolismo , Aromatase/metabolismo , Aromatase/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Progesterona/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estradiol/metabolismo , Folículo Ovariano/metabolismo
15.
J Asian Nat Prod Res ; : 1-9, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963070

RESUMO

Five new glycosides, namely methyl 3-methoxybenzoate-4,5-di-O-ß-D-glucopyranoside (1), (1aS,3aS,3R)-3-(4'-O-ß-D-glucopyranosyl-3'-methoxyphenyl)-5,6-dioxa-bicyclo[3.3.0]octane-1-one (2), quinolin-4(1H)-one-3-O-ß-D-glucopyranoside (3), 3-methoxy-propiophenone 4-O-(6'-ß-D-xylopyranosyl)-ß-D-glucopyranoside (4), methyl 3-methoxybenzoate 4-O-(6'-ß-D-xylopyranosyl)-ß-D-glucopyranoside (5), and one known compound, bambulignan B (6) were isolated from the culms of Phyllostachys nigra var. henonis. Their structures were determined using spectroscopic analysis. All compounds were evaluated for their DPPH radical scavenging activity. Compound 6 exhibited antioxidant activity with IC50 value of 59.5 µM (positive control, L-ascorbic acid, IC50 = 12.4 µM; 2,6-ditertbutyl-4-methyl phenol, IC50 = 11.8 µM).

16.
ACS Appl Mater Interfaces ; 16(29): 38490-38500, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38980000

RESUMO

High-performance electromagnetic interference (EMI) shielding materials with high flexibility, low density, and hydrophobic surface are crucial for modern integrated electronics and telecommunication systems in advanced industries like aerospace, military, artificial intelligence, and wearable electronics. In this study, we present flexible and hydrophobic MXene/Ni-coated polyester (PET) fabrics featuring a double-layered structure, fabricated via a facile and scalable dip-dry coating process followed by electroless nickel plating. Increasing the dip-dry coating iterations up to 10 cycles boosts the MXene loading content (∼31 wt %) and electrical conductivity (∼86 S/cm) of MXene-coated PET fabrics, while maintaining constant porosity (∼95%). The addition of a Ni layer enhances hydrophobicity, achieving a high water contact angle of ∼114° compared to only MXene-coated PET fabrics (∼49°). Furthermore, the 30 µm thick MXene/Ni-coated PET fabric demonstrates superior electrical conductivity (∼113.8 S/cm) and EMI shielding effectiveness (∼35.7 dB at 8-12 GHz) compared to only MXene- or Ni-coated PET fabrics. The EMI shielding performance of the MXene/Ni-coated PET fabric remains more stable in an air environment than only MXene-coated fabrics due to the outer Ni layer with excellent hydrophobicity and oxidation stability. Additionally, the MXene/Ni-coated PET fabric exhibits impressive Joule heating performance, swiftly converting electrical energy into heat and reaching high steady-state temperatures (32-92 °C) at low applied voltages (0.5-1.5 V).

17.
Bioorg Med Chem ; 110: 117828, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38981219

RESUMO

The approval of Trodelvy® validates TROP2 as a druggable but challenging target for antibody-drug conjugates (ADCs) to treat metastatic triple-negative breast cancer (mTNBC). Here, based on the TROP2-targeted antibody sacituzumab, we designed and developed several site-specific ADC candidates, which employ MMAE (monomethyl auristatin E) as the toxin, via IgG glycoengineering or affinity-directed traceless conjugation. Systematic evaluation of these site-specific ADCs in homogeneity, hydrophilicity, stability, and antitumor efficiency was conducted. The results indicate that the site-specific ADCs gsADC 3b made from one-step glycoengineering exhibit good aggregation stability and in vivo efficacy, providing a new format of ADCs that target TROP2.


Assuntos
Antígenos de Neoplasias , Antineoplásicos , Moléculas de Adesão Celular , Desenho de Fármacos , Imunoconjugados , Humanos , Imunoconjugados/química , Imunoconjugados/farmacologia , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Moléculas de Adesão Celular/antagonistas & inibidores , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/imunologia , Animais , Antineoplásicos/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Camundongos , Feminino , Estrutura Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Relação Estrutura-Atividade , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Linhagem Celular Tumoral , Anticorpos Monoclonais Humanizados/química , Anticorpos Monoclonais Humanizados/farmacologia , Oligopeptídeos
18.
NPJ Precis Oncol ; 8(1): 140, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951603

RESUMO

Early identification of IDH mutation status is of great significance in clinical therapeutic decision-making in the treatment of glioma. We demonstrate a technological solution to improve the accuracy and reliability of IDH mutation detection by combining MRI-based prediction and a CRISPR-based automatic integrated gene detection system (AIGS). A model was constructed to predict the IDH mutation status using whole slices in MRI scans with a Transformer neural network, and the predictive model achieved accuracies of 0.93, 0.87, and 0.84 using the internal and two external test sets, respectively. Additionally, CRISPR/Cas12a-based AIGS was constructed, and AIGS achieved 100% diagnostic accuracy in terms of IDH detection using both frozen tissue and FFPE samples in one hour. Moreover, the feature attribution of our predictive model was assessed using GradCAM, and the highest correlations with tumor cell percentages in enhancing and IDH-wildtype gliomas were found to have GradCAM importance (0.65 and 0.5, respectively). This MRI-based predictive model could, therefore, guide biopsy for tumor-enriched, which would ensure the veracity and stability of the rapid detection results. The combination of our predictive model and AIGS improved the early determination of IDH mutation status in glioma patients. This combined system of MRI-based prediction and CRISPR/Cas12a-based detection can be used to guide biopsy, resection, and radiation for glioma patients to improve patient outcomes.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38968045

RESUMO

BACKGROUND: The precise association between lncRNA H19 and ferroptosis in the context of atherosclerosis remains uncertain. OBJECTIVE: This study is to clarify the underlying process and propose novel approaches for the advancement of therapeutic interventions targeting atherosclerosis. METHODS: Assessment of ferroptosis, which entails the evaluation of cell viability using CCK-8 and the quantification of intracellular MDA, GSH, and ferrous ions. Simultaneously, the protein expression levels of assessed by western blot analysis, while the expression level of lncRNA H19 was also determined. Furthermore, HAECs that were cultured with ox-LDL were subjected to Fer-1 interference. HAECs were exposed to ox-LDL and then transfected with H19 shRNA and H19 overexpression vector pcDNA3.1. The level of ferroptosis in the cells was then measured. Then, HAECs were subjected to incubation with ox-LDL, followed by transfection with H19 shRNA and treated with Erastin to assess the levels of ferroptosis, cell viability, and inflammatory factor production. and the ability for blood vessel development. RESULTS: The survival rate of HAECs in the ox-LDL group was much lower. Ox-LDL resulted in an upregulation of ACSL4 expression in HAECs, while the expression of SLC7A11 and GPX4 decreased. CONCLUSIONS: lncRNA H19 enhances ferroptosis and exacerbates arterial endothelial cell damage induced by LDL.

20.
Proc Natl Acad Sci U S A ; 121(28): e2405473121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38950361

RESUMO

Cycling cells replicate their DNA during the S phase through a defined temporal program known as replication timing. Mutation frequencies, epigenetic chromatin states, and transcriptional activities are different for genomic regions that are replicated early and late in the S phase. Here, we found from ChIP-Seq analysis that DNA polymerase (Pol) κ is enriched in early-replicating genomic regions in HEK293T cells. In addition, by feeding cells with N 2-heptynyl-2'-deoxyguanosine followed by click chemistry-based enrichment and high-throughput sequencing, we observed elevated Pol κ activities in genomic regions that are replicated early in the S phase. On the basis of the established functions of Pol κ in accurate and efficient nucleotide insertion opposite endogenously induced N 2-modified dG lesions, our work suggests that active engagement of Pol κ may contribute to diminished mutation rates observed in early-replicating regions of the human genome, including cancer genomes. Together, our work expands the functions of Pol κ and offered a plausible mechanism underlying replication timing-dependent mutation accrual in the human genome.


Assuntos
Replicação do DNA , DNA Polimerase Dirigida por DNA , Fase S , Humanos , DNA Polimerase Dirigida por DNA/metabolismo , DNA Polimerase Dirigida por DNA/genética , Células HEK293 , Genoma Humano , Período de Replicação do DNA
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