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1.
Exp Cell Res ; 439(1): 114074, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710403

RESUMO

Ferroptosis inhibits tumor progression in pancreatic cancer cells, while PITX2 is known to function as a pro-oncogenic factor in various tumor types, protecting them from ferroptosis and thereby promoting tumor progression. In this study, we sought to investigate the regulatory role of PITX2 in tumor cell ferroptosis within the context of pancreatic cancer. We conducted PITX2 knockdown experiments using lentiviral infection in two pancreatic cancer cell lines, namely PANC-1 and BxPC-3. We assessed protein expression through immunoblotting and mRNA expression through RT-PCR. To confirm PITX2 as a transcription factor for GPX4, we employed Chromatin Immunoprecipitation (ChIP) and Dual-luciferase assays. Furthermore, we used flow cytometry to measure reactive oxygen species (ROS), lipid peroxidation, and apoptosis and employed confocal microscopy to assess mitochondrial membrane potential. Additionally, electron microscopy was used to observe mitochondrial structural changes and evaluate PITX2's regulation of ferroptosis in pancreatic cancer cells. Our findings demonstrated that PITX2, functioning as a transcription factor for GPX4, promoted GPX4 expression, thereby exerting an inhibitory effect on ferroptosis in pancreatic cancer cells and consequently promoting tumor progression. Moreover, PITX2 enhanced the invasive and migratory capabilities of pancreatic cancer cells by activating the WNT signaling pathway. Knockdown of PITX2 increased ferroptosis and inhibited the proliferation of PANC-1 and BxPC-3 cells. Notably, the inhibitory effect on ferroptosis resulting from PITX2 overexpression in these cells could be countered using RSL3, an inhibitor of GPX4. Overall, our study established PITX2 as a transcriptional regulator of GPX4 that could promote tumor progression in pancreatic cancer by reducing ferroptosis. These findings suggest that PITX2 may serve as a potential therapeutic target for combating ferroptosis in pancreatic cancer.


Assuntos
Ferroptose , Regulação Neoplásica da Expressão Gênica , Proteína Homeobox PITX2 , Proteínas de Homeodomínio , Neoplasias Pancreáticas , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Espécies Reativas de Oxigênio , Fatores de Transcrição , Animais , Humanos , Camundongos , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Ferroptose/genética , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Peroxidação de Lipídeos , Potencial da Membrana Mitocondrial/genética , Camundongos Nus , Mitocôndrias/metabolismo , Mitocôndrias/genética , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Via de Sinalização Wnt/genética
2.
Nucleic Acids Res ; 51(6): 2740-2758, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36864759

RESUMO

In CRISPR/Cas9 genome editing, the tight and persistent target binding of Cas9 provides an opportunity for efficient genetic and epigenetic modification on genome. In particular, technologies based on catalytically dead Cas9 (dCas9) have been developed to enable genomic regulation and live imaging in a site-specific manner. While post-cleavage target residence of CRISPR/Cas9 could alter the pathway choice in repair of Cas9-induced DNA double strand breaks (DSBs), it is possible that dCas9 residing adjacent to a break may also determine the repair pathway for this DSB, providing an opportunity to control genome editing. Here, we found that loading dCas9 onto a DSB-adjacent site stimulated homology-directed repair (HDR) of this DSB by locally blocking recruitment of classical non-homologous end-joining (c-NHEJ) factors and suppressing c-NHEJ in mammalian cells. We further repurposed dCas9 proximal binding to increase HDR-mediated CRISPR genome editing by up to 4-fold while avoiding exacerbation of off-target effects. This dCas9-based local inhibitor provided a novel strategy of c-NHEJ inhibition in CRISPR genome editing in place of small molecule c-NHEJ inhibitors, which are often used to increase HDR-mediated genome editing but undesirably exacerbate off-target effects.


Assuntos
Sistemas CRISPR-Cas , Quebras de DNA de Cadeia Dupla , Animais , Reparo do DNA por Junção de Extremidades , Reparo de DNA por Recombinação , Edição de Genes/métodos , DNA/genética , Reparo do DNA , Mamíferos/genética
3.
Br J Cancer ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877108

RESUMO

BACKGROUND: Targeting DNA damage repair factors, such as DNA-dependent protein kinase catalytic subunit (DNA-PKcs), may offer an opportunity for effective treatment of multiple myeloma (MM). In combination with DNA damage-inducing agents, this strategy has been shown to improve chemotherapies partially via activation of cGAS-STING pathway by an elevated level of cytosolic DNA. However, as cGAS is primarily sequestered by chromatin in the nucleus, it remains unclear how cGAS is released from chromatin and translocated into the cytoplasm upon DNA damage, leading to cGAS-STING activation. METHODS: We examined the role of DNA-PKcs inhibition on cGAS-STING-mediated MM chemosensitivity by performing mass spectrometry and mechanism study. RESULTS: Here, we found DNA-PKcs inhibition potentiated DNA damage-inducing agent doxorubicin-induced anti-MM effect by activating cGAS-STING signaling. The cGAS-STING activation in MM cells caused cell death partly via IRF3-NOXA-BAK axis and induced M1 polarization of macrophages. Moreover, this activation was not caused by defective classical non-homologous end joining (c-NHEJ). Instead, upon DNA damage induced by doxorubicin, inhibition of DNA-PKcs promoted cGAS release from cytoplasmic chromatin fragments and increased the amount of cytosolic cGAS and DNA, activating cGAS-STING. CONCLUSIONS: Inhibition of DNA-PKcs could improve the efficacy of doxorubicin in treatment of MM by de-sequestrating cGAS in damaged chromatin.

4.
Virol J ; 21(1): 7, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178138

RESUMO

BACKGROUND: Oncolytic viruses are being studied and developed as novel cancer treatments. Using directed evolution technology, structural modification of the viral surface protein increases the specificity of the oncolytic virus for a particular cancer cell. Newcastle disease virus (NDV) does not show specificity for certain types of cancer cells during infection; therefore, it has low cancer cell specificity. Hemagglutinin is an NDV receptor-binding protein on the cell surface that determines host cell tropism. NDV selectivity for specific cancer cells can be increased by artificial amino acid changes in hemagglutinin neuraminidase HN proteins via directed evolution, leading to improved therapeutic effects. METHODS: Sialic acid-binding sites (H domains) of the HN protein mutant library were generated using error-prone PCR. Variants of the H domain protein were screened by enzyme-linked immunosorbent assay using HCT 116 cancer cell surface molecules. The mutant S519G H domain protein showed the highest affinity for the surface protein of HCT 116 cells compared to that of different types of cancer cells. This showed that the S519G mutant H domain protein gene replaced the same part of the original HN protein gene, and S519G mutant recombinant NDV (rNDV) was constructed and recovered. S519G rNDV cancer cell killing effects were tested using the MTT assay with various cancer cell types, and the tumor suppression effect of the S519G mutant rNDV was tested in a xenograft mouse model implanted with cancer cells, including HCT 116 cells. RESULTS: S519G rNDV showed increased specificity and enhanced killing ability of HCT 116 cells among various cancer cells and a stronger suppressive effect on tumor growth than the original recombinant NDV. Directed evolution using an artificial amino acid change in the NDV HN (S519G mutant) protein increased its specificity and oncolytic effect in colorectal cancer without changing its virulence. CONCLUSION: These results provide a new methodology for the use of directed evolution technology for more effective oncolytic virus development.


Assuntos
Neoplasias Colorretais , Vírus Oncolíticos , Humanos , Animais , Camundongos , Vírus da Doença de Newcastle/genética , Vírus da Doença de Newcastle/metabolismo , Proteína HN/genética , Proteína HN/metabolismo , Neuraminidase/genética , Neuraminidase/metabolismo , Hemaglutininas , Ácido N-Acetilneuramínico/metabolismo , Células HCT116 , Vírus Oncolíticos/genética , Modelos Animais de Doenças , Proteínas de Membrana , Neoplasias Colorretais/terapia
5.
Phys Chem Chem Phys ; 26(2): 1190-1204, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38099645

RESUMO

The ligands, derived from the combination of phenanthroline and various five-membered N-heterocyclic rings, were subject to a comprehensive investigation for their potential in the extraction and separation of actinides and lanthanides. This study employed DFT methods to thoroughly explore the properties of both phenanthroline (Ph) and the diverse five-membered N-heterocyclic rings (R1-R8). Additionally, tridentate ligands RlPh (l = 1-8) and tetradentate ligands RlPhRr (l, r = 1-8) were analyzed in detail, encompassing their electrostatic potential (ESP), protonation energy, coordination bonding with the metals Am(III) and Eu(III), and the thermodynamics of extraction separation for Am(III) and Eu(III). The findings highlight that the electrostatic potential (ESP) and binding capabilities of the five-membered N-heterocyclic ring units serve as effective predictors for the properties of intricate tridentate and tetradentate ligands, as well as their coordination bonding affinity with metals. The ligands' binding energy is closely associated with their ESP, and notably, the binding energy of tridentate and tetradentate ligands correlates well with the binding energies of their constituent structural units. The computational results reveal that the R2 unit, along with its corresponding tridentate ligand R2Ph and tetradentate ligands R2PhRr, exhibits the highest ESP, superior binding energies, and the strongest coordination bonding affinity with the metals. The theoretical calculations further identify several promising extractants for the effective separation of Am(III) and Eu(III). The tridentate ligands R1Ph, R7Ph, and R4Ph, and the tetradentate ligands R4PhR4, R6PhR6, R2PhR2, R1PhR5 and R3PhR6 were identified as having excellent separation performance for Am(III) and Eu(III). This study would provide insights for the design of extractants for the separation of Am(III) and Eu(III) by use of five-membered N-heterocyclic rings as structural units.

6.
Phys Chem Chem Phys ; 26(3): 2205-2217, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38164958

RESUMO

The separation of trivalent actinide elements from lanthanide elements represents one of the most formidable challenges within the context of nuclear waste partitioning and transmutation (P&T) processes. Consequently, we embarked on a systematic investigation aimed at elucidating the bonding properties and thermodynamic behavior of a N-ethyl-N-tolyl-2-amide-1,10-phenanthroline (Et-Tol-PTA) ligand in conjunction with trivalent actinide and lanthanide elements. This investigation involved the utilization of various density functional theory (DFT) methods and a comparative analysis between small-core pseudopotential basis sets and all-electron basis sets. It was found that well-performing results were achieved using the PBE0 functional in both bond length and thermodynamic energy calculations, with minimal impact being exerted by the basis set on the results. Furthermore, an exploration was carried out into the bonding and thermodynamic properties of trivalent actinides and lanthanides with ligands derived from Et-Tol-PTA, encompassing non-rigid (La), partially rigid (Lb, Lc), and rigid (Ld) ligands. Thermodynamically, advantages in the separation of Am(III)/Eu(III) were exhibited by Lb and Lc ligands, while excellent performance in the separation of Am(III)/Cm(III) was demonstrated by the La ligand. Analyses conducted using quantum theory of atoms in molecules (QTAIM), reduced density gradient (RDG), and natural bond orbital (NBO) methodologies revealed the presence of partial covalent character in the bonds between oxygen (O) and metal (M), as well as between nitrogen (N) and metal (M), with a higher degree of covalent character being observed in O-Am and N-Am bonds compared to O-Cm/Eu and N-Cm/Eu interactions.

7.
Chin J Traumatol ; 27(1): 42-52, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37953130

RESUMO

PURPOSE: Mannitol is one of the first-line drugs for reducing cerebral edema through increasing the extracellular osmotic pressure. However, long-term administration of mannitol in the treatment of cerebral edema triggers damage to neurons and astrocytes. Given that neural stem cell (NSC) is a subpopulation of main regenerative cells in the central nervous system after injury, the effect of mannitol on NSC is still elusive. The present study aims to elucidate the role of mannitol in NSC proliferation. METHODS: C57 mice were derived from the animal house of Zunyi Medical University. A total of 15 pregnant mice were employed for the purpose of isolating NSCs in this investigation. Initially, mouse primary NSCs were isolated from the embryonic cortex of mice and subsequently identified through immunofluorescence staining. In order to investigate the impact of mannitol on NSC proliferation, both cell counting kit-8 assays and neurospheres formation assays were conducted. The in vitro effects of mannitol were examined at various doses and time points. In order to elucidate the role of Aquaporin 4 (AQP4) in the suppressive effect of mannitol on NSC proliferation, various assays including reverse transcription polymerase chain reaction, western blotting, and immunocytochemistry were conducted on control and mannitol-treated groups. Additionally, the phosphorylated p38 (p-p38) was examined to explore the potential mechanism underlying the inhibitory effect of mannitol on NSC proliferation. Finally, to further confirm the involvement of the p38 mitogen-activated protein kinase-dependent (MAPK) signaling pathway in the observed inhibition of NSC proliferation by mannitol, SB203580 was employed. All data were analyzed using SPSS 20.0 software (SPSS, Inc., Chicago, IL). The statistical analysis among multiple comparisons was performed using one-way analysis of variance (ANOVA), followed by Turkey's post hoc test in case of the data following a normal distribution using a Shapiro-Wilk normality test. Comparisons between 2 groups were determined using Student's t-test, if the data exhibited a normal distribution using a Shapiro-Wilk normality test. Meanwhile, data were shown as median and interquartile range and analyzed using the Mann-Whitney U test, if the data failed the normality test. A p < 0.05 was considered as significant difference. RESULTS: Primary NSC were isolated from the mice, and the characteristics were identified using immunostaining analysis. Thereafter, the results indicated that mannitol held the capability of inhibiting NSC proliferation in a dose-dependent and time-dependent manner using cell counting kit-8, neurospheres formation, and immunostaining of Nestin and Ki67 assays. During the process of mannitol suppressing NSC proliferation, the expression of AQP4 mRNA and protein was downregulated, while the gene expression of p-p38 was elevated by reverse transcription polymerase chain reaction, immunostaining, and western blotting assays. Subsequently, the administration of SB203580, one of the p38 MAPK signaling pathway inhibitors, partially abrogated this inhibitory effect resulting from mannitol, supporting the fact that the p38 MAPK signaling pathway participated in curbing NSC proliferation induced by mannitol. CONCLUSIONS: Mannitol inhibits NSC proliferation through downregulating AQP4, while upregulating the expression of p-p38 MAPK.


Assuntos
Edema Encefálico , Células-Tronco Neurais , Humanos , Animais , Manitol/farmacologia , Células-Tronco Neurais/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/farmacologia , Proliferação de Células
8.
Chin J Traumatol ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637176

RESUMO

PURPOSE: Traumatic brain injury (TBI), currently a major global public health problem, imposes a significant economic burden on society and families. We aimed to quantify and predict the incidence and severity of TBI by analyzing its incidence, prevalence, and years lived with disability (YLDs). The epidemiological changes in TBI from 1990 to 2019 were described and updated to provide a reference for developing prevention, treatment, and incidence-reducing measures for TBI. METHODS: A secondary analysis was performed on the incidence, prevalence, and YLDs of TBI by sex, age group, and region (n = 21,204 countries and territories) between 1990 and 2019 using the Global Burden of Diseases, Injuries, and Risk Factors Study 2019. Proportions in the age-standardized incidence rate due to underlying causes of TBI and proportions of minor and moderate or severe TBI were also reported. RESULTS: In 2019, there were 27.16 million (95% uncertainty intervals (UI): 23.36 - 31.42) new cases of TBI worldwide, with age-standardized incidence and prevalence rates of 346 per 100,000 population (95% UI: 298-401) and 599 per 100,000 population (95% UI: 573-627), respectively. From 1990 to 2019, there were no significant trends in global age-standardized incidence (estimated annual percentage changes: -0.11%, 95% UI: -0.18% - -0.04%) or prevalence (estimated annual percentage changes: 0.01%, 95% UI: -0.04% - 0.06%). TBI caused 7.08 million (95% UI: 5.00 - 9.59) YLDs in 2019, with age-standardized rates of 86.5 per 100,000 population (95% UI: 61.1 - 117.2). In 2019, the countries with higher incidence rates were mainly distributed in Central Europe, Eastern Europe, and Australia. The 2019 global age-standardized incidence rate was higher in males than in females. The 2019 global incidence of moderate and severe TBI was 182.7 per 100,000 population, accounting for 52.8% of all TBI, with falls and road traffic injuries being the main causes in most regions. CONCLUSIONS: The incidence of moderate and severe TBI was slightly higher in 2019, and TBI still accounts for a significant portion of the global injury burden. The likelihood of moderate to severe TBI and the trend of major injury under each injury cause from 1990 to 2019 and the characteristics of injury mechanisms in each age group are presented, providing a basis for further research on injury causes in each age group and the future establishment of corresponding policies and protective measures.

9.
Planta ; 258(1): 7, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37222817

RESUMO

MAIN CONCLUSION: The 4-coumarate:coenzyme A ligase 4CL4 is involved in enhancing rice P acquisition and use in acid soil by enlarging root growth and boosting functional rhizosphere microbe recruitment. Rice (Oryza sativa L.) cannot easily acquire phosphorus (P) from acid soil, where root growth is inhibited and soil P is fixed. The combination of roots and rhizosphere microbiota is critical for plant P acquisition and soil P mobilization, but the associated molecular mechanism in rice is unclear. 4CL4/RAL1 encodes a 4-coumarate:coenzyme A ligase related to lignin biosynthesis in rice, and its dysfunction results in a small rice root system. In this study, soil culture and hydroponic experiments were conducted to examine the role of RAL1 in regulating rice P acquisition, fertilizer P use, and rhizosphere microbes in acid soil. Disruption of RAL1 markedly decreased root growth. Mutant rice plants exhibited decreased shoot growth, shoot P accumulation, and fertilizer P use efficiency when grown in soil-but not under hydroponic conditions, where all P is soluble and available for plants. Mutant ral1 and wild-type rice rhizospheres had distinct bacterial and fungal community structures, and wild-type rice recruited some genotype-specific microbial taxa associated with P solubilization. Our results highlight the function of 4CL4/RAL1 in enhancing rice P acquisition and use in acid soil, namely by enlarging root growth and boosting functional rhizosphere microbe recruitment. These findings can inform breeding strategies to improve P use efficiency through host genetic manipulation of root growth and rhizosphere microbiota.


Assuntos
Coenzima A Ligases , Oryza , Fósforo , Rizosfera , Coenzima A Ligases/genética , Fertilizantes , Oryza/genética , Melhoramento Vegetal , Solo
10.
Metabolomics ; 19(6): 58, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37289273

RESUMO

BACKGROUND AND AIMS: SKN-1, a C. elegans transcription factor analogous to the mammalian NF-E2-related factor (Nrf2), has been known to promote oxidative stress resistance aiding nematodes' longevity. Although SKN-1's functions suggest its implication in lifespan modulation through cellular metabolism, the actual mechanism of how metabolic rearrangements contribute to SKN-1's lifespan modulation has yet to be well characterized. Therefore, we performed the metabolomic profiling of the short-lived skn-1-knockdown C. elegans. METHODS: We analyzed the metabolic profile of the skn-1-knockdown worms with nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography-tandem mass spectrometry (LC-MS/MS) and obtained distinctive metabolomic profiles compared to WT worms. We further extended our study with gene expression analysis to examine the expression level of genes encoding all metabolic enzymes. RESULTS: A significant increase in the phosphocholine and AMP/ATP ratio, potential biomarkers of aging, was observed, accompanied by a decrease in the transsulfuration metabolites, NADPH/NADP+ ratio, and total glutathione (GSHt), which are known to be involved in oxidative stress defense. skn-1-RNAi worms also exhibited an impairment in the phase II detoxification system, confirmed by the lower conversion rate of paracetamol to paracetamol-glutathione. By further examining the transcriptomic profile, we found a decrease in the expression of cbl-1, gpx, T25B9.9, ugt, and gst, which are involved in GSHt and NADPH synthesis as well as in the phase II detoxification system. CONCLUSION: Our multi-omics results consistently revealed that the cytoprotective mechanisms, including cellular redox reactions and xenobiotic detoxification system, contribute to the roles of SKN-1/Nrf2 in the lifespan of worms.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Acetaminofen/metabolismo , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Cromatografia Líquida , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Glutationa/metabolismo , Longevidade/genética , Mamíferos/metabolismo , Metabolômica , NADP/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Espectrometria de Massas em Tandem
11.
J Phys Chem A ; 127(33): 6865-6880, 2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37583058

RESUMO

Designing ligands that can effectively separate actinide An(III)/lanthanide Ln(III) in the solvent extraction process remains one of the key issues in the treatment of accumulated spent nuclear fuel. Nitrogen donor ligands are considered as promising extractants for the separation of An(III) and Ln(III) due to their environmental friendliness. Four new macrocyclic N-donor hexadentate extractants were designed and their coordination with Am(III) and Eu(III), as well as their extraction selectivity and separation performance for Am(III) and Eu(III), were investigated by scalar relativistic density functional theory. A variety of theoretical methods have been used to evaluate the properties of the four ligands and the coordination structures, bonding properties, and thermodynamic properties of the complexes formed by the four ligands with Am(III) and Eu(III). The results of various wavefunction analysis methods including NBO analysis, quantum theory of atoms in molecules (QTAIM) analysis, and so on show that Am(III) has a stronger coordination ability with the ligands than Eu(III) due to the Am 5f orbitals more involved in bonding with the ligands than the Eu 4f orbitals, and the bonding environment of the N-donor in the ligand has a significant effect on its coordination ability of the metal ions. Thermodynamic analysis of the solvent extraction process shows that all of the four N-containing macrocyclic ligands have good extraction selectivity and separation performance for Am(III) and Eu(III). This study provides theoretical support for designing potential nitrogen-containing macrocyclic extractants with excellent separation performance.

12.
Acta Pharmacol Sin ; 44(3): 670-679, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36100765

RESUMO

Temozolomide (TMZ) has been used as standard-of-care for glioblastoma multiforme (GBM), but the resistance to TMZ develops quickly and frequently. Thus, more studies are needed to elucidate the resistance mechanisms. In the current study, we investigated the relationship among the three important phenotypes, namely TMZ-resistance, cell shape and lipid metabolism, in GBM cells. We first observed the distinct difference in cell shapes between TMZ-sensitive (U87) and resistant (U87R) GBM cells. We then conducted NMR-based lipid metabolomics, which revealed a significant increase in cholesterol and fatty acid synthesis as well as lower lipid unsaturation in U87R cells. Consistent with the lipid changes, U87R cells exhibited significantly lower membrane fluidity. The transcriptomic analysis demonstrated that lipid synthesis pathways through SREBP were upregulated in U87R cells, which was confirmed at the protein level. Fatostatin, an SREBP inhibitor, and other lipid pathway inhibitors (C75, TOFA) exhibited similar or more potent inhibition on U87R cells compared to sensitive U87 cells. The lower lipid unsaturation ratio, membrane fluidity and higher fatostatin sensitivity were all recapitulated in patient-derived TMZ-resistant primary cells. The observed ternary relationship among cell shape, lipid composition, and TMZ-resistance may be applicable to other drug-resistance cases. SREBP and fatostatin are suggested as a promising target-therapeutic agent pair for drug-resistant glioblastoma.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Temozolomida/uso terapêutico , Glioblastoma/tratamento farmacológico , Forma Celular , Metabolismo dos Lipídeos , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Resistencia a Medicamentos Antineoplásicos , Lipídeos , Linhagem Celular Tumoral , Neoplasias Encefálicas/tratamento farmacológico , Antineoplásicos Alquilantes/farmacologia
13.
Acta Pharmacol Sin ; 44(2): 406-420, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35906293

RESUMO

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease. Cyst development in ADPKD involves abnormal epithelial cell proliferation, which is affected by the primary cilia-mediated signal transduction in the epithelial cells. Thus, primary cilium has been considered as a therapeutic target for ADPKD. Since ADPKD exhibits many pathological features similar to solid tumors, we investigated whether targeting primary cilia using anti-tumor agents could alleviate the development of ADPKD. Twenty-four natural compounds with anti-tumor activity were screened in MDCK cyst model, and 1-Indanone displayed notable inhibition on renal cyst growth without cytotoxicity. This compound also inhibited cyst development in embryonic kidney cyst model. In neonatal kidney-specific Pkd1 knockout mice, 1-Indanone remarkably slowed down kidney enlargement and cyst expansion. Furthermore, we demonstrated that 1-Indanone inhibited the abnormal elongation of cystic epithelial cilia by promoting tubulin polymerization and significantly down-regulating expression of anterograde transport motor protein KIF3A and IFT88. Moreover, we found that 1-Indanone significantly down-regulated ciliary coordinated Wnt/ß-catenin, Hedgehog signaling pathways. These results demonstrate that 1-Indanone inhibits cystic cell proliferation by reducing abnormally prolonged cilia length in cystic epithelial cells, suggesting that 1-Indanone may hold therapeutic potential to retard cyst development in ADPKD.


Assuntos
Cistos , Rim Policístico Autossômico Dominante , Camundongos , Animais , Rim Policístico Autossômico Dominante/tratamento farmacológico , Rim Policístico Autossômico Dominante/metabolismo , Rim Policístico Autossômico Dominante/patologia , Cílios , Tubulina (Proteína)/metabolismo , Proteínas Hedgehog/metabolismo , Rim/patologia , Camundongos Knockout , Cistos/metabolismo , Cistos/patologia , Canais de Cátion TRPP/metabolismo , Células Epiteliais/metabolismo
14.
Acta Biochim Biophys Sin (Shanghai) ; 55(9): 1393-1403, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37337632

RESUMO

Since the prognosis of patients with pancreatic cancer is very poor and there is a lack of treatment methods, this study is performed to investigate the function of PITX2 in pancreatic stellate cells (PSCs) in the progression of pancreatic cancer. Scientific hypotheses are proposed according to bioinformatics analysis and tissue microarray analysis. Stable knockdown of PITX2 in PSCs is achieved through lentiviral infection. The relative expressions of PITX2, α-SMA, vimentin, CTNNB1, AXIN1 and LEF1 are measured in wild-type PSCs and PITX2-knockdown PSCs. Proliferative capacity is measured by EdU assay. After coculture with PSCs, the proliferation, invasion and migration capacity of pancreatic cancer cells are tested. EMT and Wnt/ß-catenin downstream genes of pancreatic cancer cells are investigated to reveal the potential mechanism. Bioinformatics analysis reveals that the PITX2 gene is highly expressed in stromal cells in pancreatic cancer and is correlated with squamous-type PDAC. Analysis of PDAC tissue microarray further demonstrates that high PITX2 level in stromal cells is correlated with poor prognosis in PDAC. After stable knockdown of PITX2 in PSCs, the relative protein levels of α-SMA, vimentin, CTNNB1, AXIN1 and LEF1 are decreased, and the proliferative capacity of PSCs is also decreased. After coculture with PSCs, in which PITX2 expression is downregulated, the proliferation, invasion and migration capacities of pancreatic cancer cells are inhibited. Thus, our results show that PITX2-silenced PSCs inhibit the growth, migration and invasion of pancreatic cancer cells via reduced EMT and Wnt/ß-catenin signaling.


Assuntos
Neoplasias Pancreáticas , beta Catenina , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Vimentina/genética , Vimentina/metabolismo , Células Estreladas do Pâncreas/metabolismo , Movimento Celular/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Via de Sinalização Wnt/genética , Linhagem Celular Tumoral , Proliferação de Células/genética
15.
PLoS Genet ; 16(11): e1009114, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33175845

RESUMO

Soybean [Glycine max (L.) Merr.] was domesticated from wild soybean (G. soja Sieb. and Zucc.) and has been further improved as a dual-use seed crop to provide highly valuable oil and protein for food, feed, and industrial applications. However, the underlying genetic and molecular basis remains less understood. Having combined high-confidence bi-parental linkage mapping with high-resolution association analysis based on 631 whole sequenced genomes, we mapped major soybean protein and oil QTLs on chromosome15 to a sugar transporter gene (GmSWEET39). A two-nucleotide CC deletion truncating C-terminus of GmSWEET39 was strongly associated with high seed oil and low seed protein, suggesting its pleiotropic effect on protein and oil content. GmSWEET39 was predominantly expressed in parenchyma and integument of the seed coat, and likely regulates oil and protein accumulation by affecting sugar delivery from maternal seed coat to the filial embryo. We demonstrated that GmSWEET39 has a dual function for both oil and protein improvement and undergoes two different paths of artificial selection. A CC deletion (CC-) haplotype H1 has been intensively selected during domestication and extensively used in soybean improvement worldwide. H1 is fixed in North American soybean cultivars. The protein-favored (CC+) haplotype H3 still undergoes ongoing selection, reflecting its sustainable role for soybean protein improvement. The comprehensive knowledge on the molecular basis underlying the major QTL and GmSWEET39 haplotypes associated with soybean improvement would be valuable to design new strategies for soybean seed quality improvement using molecular breeding and biotechnological approaches.


Assuntos
Glycine max/genética , Proteínas de Transporte de Monossacarídeos/genética , Melhoramento Vegetal , Proteínas de Plantas/genética , Mapeamento Cromossômico , Genoma de Planta/genética , Estudo de Associação Genômica Ampla , Haplótipos , Proteínas de Transporte de Monossacarídeos/metabolismo , América do Norte , Óleos de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Vegetais Comestíveis/biossíntese , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Sementes/metabolismo , Glycine max/metabolismo
16.
J Acoust Soc Am ; 154(3): 1871-1881, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37756575

RESUMO

The aim of this work is to investigate and analyze the operation mechanism and power control principle of a bolted Langevin type (BLT)-loaded phase-shifted control inverter and to find a safe power control method for a phase-shifted control inverter used to drive a high-power BLT by preventing the differential current (shock current) from occurring in the right branches of a phase-shifted full-bridge circuit. In this paper, by allowing the inverter operating frequency to operate under inductive loads that coincide with the zero points of voltage and current rather than the resonant frequency of the BLT, which results in the generation of a shock current in the right branch of the full-bridge circuit, the switches of the right-branch also enabled zero-voltage, zero-current switching on (ZVZCS turn-on). The proposed method can fundamentally eliminate the generation of shock current by realizing ZVZCS turn-on on the right-branch switch elements of the inverter. The phase-shift angle control limit for power control by this scheme is 90° and the power control range is 20%-100%.

17.
Chin J Traumatol ; 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38061929

RESUMO

PURPOSE: The study aimed to examine the pattern of motorization and the mortality rate related to road traffic crashes in Zunyi (a city in northern Guizhou province of China) from 2013 to 2022, and to identify the epidemiological characteristics of these crashes with to provide insights that could help improve road safety. METHODS: Data were obtained from the Zunyi traffic management data platform, and the mortality rates were calculated. We deployed various analytical methods, including descriptive analysis, Chi-square test or Fisher's exact test of categorical variable, circular distribution map analysis, and Rayleigh test to characterize the traits of road traffic crashes in the region. RESULTS: During the 10-year study period, 7488 people died due to road traffic accidents, with males accounting for 70.4% and females 29.6% (χ2 = 101.97, p < 0.001). The mortality rate increased from 7.80 deaths per 100,000 people in 2013 to 10.70 deaths per 100,000 people in 2016, but then decreased to 9.54 deaths per 100,000 people in 2019. A notable finding was that the death rate per 10,000 vehicles declined from 16.09 deaths per 10,000 vehicles in 2013 to 5.48 deaths per 10,000 vehicles in 2022. The study also found that vulnerable road users represented nearly half (48.76%) of all accident fatalities, and unlicensed or inexperienced driving contributed significantly to the occurrence of road traffic accidents. CONCLUSION: Although the number of road traffic accidents in Zunyi has decreased, there are still some critical issues that need to be addressed, particularly for vulnerable road users and unlicensed drivers. Our results highlight the need of targeted interventions to address the specific risk factors of road traffic crashes, particularly those affecting vulnerable road users and drivers without sufficient experience or license.

18.
BMC Genomics ; 23(1): 250, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361112

RESUMO

BACKGROUND: With advances in next-generation sequencing technologies, an unprecedented amount of soybean accessions has been sequenced by many individual studies and made available as raw sequencing reads for post-genomic research. RESULTS: To develop a consolidated and user-friendly genomic resource for post-genomic research, we consolidated the raw resequencing data of 1465 soybean genomes available in the public and 91 highly diverse wild soybean genomes newly sequenced. These altogether provided a collection of 1556 sequenced genomes of 1501 diverse accessions (1.5 K). The collection comprises of wild, landraces and elite cultivars of soybean that were grown in East Asia or major soybean cultivating areas around the world. Our extensive sequence analysis discovered 32 million single nucleotide polymorphisms (32mSNPs) and revealed a SNP density of 30 SNPs/kb and 12 non-synonymous SNPs/gene reflecting a high structural and functional genomic diversity of the new collection. Each SNP was annotated with 30 categories of structural and/or functional information. We further identified paired accessions between the 1.5 K and 20,087 (20 K) accessions in US collection as genomic "equivalent" accessions sharing the highest genomic identity for minimizing the barriers in soybean germplasm exchange between countries. We also exemplified the utility of 32mSNPs in enhancing post-genomics research through in-silico genotyping, high-resolution GWAS, discovering and/or characterizing genes and alleles/mutations, identifying germplasms containing beneficial alleles that are potentially experiencing artificial selection. CONCLUSION: The comprehensive analysis of publicly available large-scale genome sequencing data of diverse cultivated accessions and the newly in-house sequenced wild accessions greatly increased the soybean genome-wide variation resolution. This could facilitate a variety of genetic and molecular-level analyses in soybean. The 32mSNPs and 1.5 K accessions with their comprehensive annotation have been made available at the SoyBase and Ag Data Commons. The dataset could further serve as a versatile and expandable core resource for exploring the exponentially increasing genome sequencing data for a variety of post-genomic research.


Assuntos
Genômica , Glycine max , Mapeamento Cromossômico , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , Glycine max/genética
19.
J Am Chem Soc ; 144(19): 8529-8535, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35535499

RESUMO

Gut microbiome can affect drug metabolism considerably, leading to modified drug response. However, quantitative estimation of host vs. microbial contributions in a living host-gut microbiome system has been challenging. Using the interspecies system of Caenorhabditis elegans and gut bacteria, we developed a real-time approach for monitoring their metabolic interaction in vivo during anticancer drug 5-fluorouracil (5-FU) metabolism. The fluorine NMR-based approach yielded the quantitative contributions to the host 5-FU metabolism made by human gut-microbial species of variable genetic backgrounds. It also experimentally confirmed a bacterial gene-metabolism relationship. Differential 5-FU catabolism among bacterial substrains and the contributions to the host metabolism, unobservable by conventional 16S rRNA metagenomic sequencing, were also found. The metabolic contributions could be correlated with phenotypic developmental toxicity of 5-FU to the host fed with different substrains. Our convenient platform should help to reveal heterogeneity in host-gut microbiome interactions for many drugs in a living symbiotic system.


Assuntos
Antineoplásicos , Microbioma Gastrointestinal , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Bactérias/metabolismo , Fluoruracila/farmacologia , Humanos , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo
20.
Small ; 18(3): e2103617, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34585510

RESUMO

Solid-state polymer electrolytes (SPEs) for high electrochemical performance lithium-ion batteries have received considerable attention due to their unique characteristics; they are not prone to leakage, and they exhibit low flammability, excellent processability, good flexibility, high safety levels, and superior thermal stability. However, current SPEs are far from commercialization, mainly due to the low ionic conductivity, low Li+ transference number (tLi+ ), poor electrode/electrolyte interface contact, narrow electrochemical oxidation window, and poor long-term stability of Li metal. Recent work on improving electrochemical performance and these aspects of SPEs are summarized systematically here with a particular focus on the underlying mechanisms, and the improvement strategies are also proposed. This review could lead to a deeper consideration of the issues and solutions affecting the application of SPEs and pave a new pathway to safe, high-performance lithium-ion batteries.

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