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1.
Nature ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926571

RESUMO

Tissue repair, immune defence and cancer progression rely on a vital cellular decision between quiescence and proliferation1,2. Mammalian cells proliferate by triggering a positive feedback mechanism3,4. The transcription factor E2F activates cyclin-dependent kinase 2 (CDK2), which in turn phosphorylates and inactivates the E2F inhibitor protein retinoblastoma (Rb). This action further increases E2F activity to express genes needed for proliferation. Given that positive feedback can inadvertently amplify small signals, understanding how cells keep this positive feedback in check remains a puzzle. Here we measured E2F and CDK2 signal changes in single cells and found that the positive feedback mechanism engages only late in G1 phase. Cells spend variable and often extended times in a reversible state of intermediate E2F activity before committing to proliferate. This intermediate E2F activity is proportional to the amount of phosphorylation of a conserved T373 residue in Rb that is mediated by CDK2 or CDK4/CDK6. Such T373-phosphorylated Rb remains bound on chromatin but dissociates from it once Rb is hyperphosphorylated at many sites, which fully activates E2F. The preferential initial phosphorylation of T373 can be explained by its relatively slower rate of dephosphorylation. Together, our study identifies a primed state of intermediate E2F activation whereby cells sense external and internal signals and decide whether to reverse and exit to quiescence or trigger the positive feedback mechanism that initiates cell proliferation.

2.
BMC Genomics ; 25(1): 325, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561670

RESUMO

BACKGROUND: Non-coding RNA is a key epigenetic regulation factor during skeletal muscle development and postnatal growth, and miR-542-3p was reported to be conserved and highly expressed in the skeletal muscle among different species. However, its exact functions in the proliferation of muscle stem cells and myogenesis remain to be determined. METHODS: Transfection of proliferative and differentiated C2C12 cells used miR-542-3p mimic and inhibitor. RT-qPCR, EdU staining, immunofluorescence staining, cell counting kit 8 (CCK-8), and Western blot were used to evaluate the proliferation and myogenic differentiation caused by miR-542-3p. The dual luciferase reporter analysis and rescued experiment of the target gene were used to reveal the molecular mechanism. RESULTS: The data shows overexpression of miR-542-3p downregulation of mRNA and protein levels of proliferation marker genes, reduction of EdU+ cells, and cellular vitality. Additionally, knocking it down promoted the aforementioned phenotypes. For differentiation, the miR-542-3p gain-of-function reduced both mRNA and protein levels of myogenic genes, including MYOG, MYOD1, et al. Furthermore, immunofluorescence staining immunized by MYHC antibody showed that the myotube number, fluorescence intensity, differentiation index, and myotube fusion index all decreased in the miR-542-3p mimic group, compared with the control group. Conversely, these phenotypes exhibited an increased trend in the miR-542-3p inhibitor group. Mechanistically, phosphatase and tensin homolog (Pten) was identified as the bona fide target gene of miR-542-3p by dual luciferase reporter gene assay, si-Pten combined with miR-542-3p inhibitor treatments totally rescued the promotion of proliferation by loss-function of miR-542-3p. CONCLUSIONS: This study indicates that miR-542-3p inhibits the proliferation and differentiation of myoblast and Pten is a dependent target gene of miR-542-3p in myoblast proliferation, but not in differentiation.


Assuntos
MicroRNAs , MicroRNAs/genética , MicroRNAs/metabolismo , Epigênese Genética , Proliferação de Células/genética , Diferenciação Celular/genética , RNA Mensageiro/metabolismo , Desenvolvimento Muscular/genética , Mioblastos , Luciferases/genética , Luciferases/metabolismo
3.
Sensors (Basel) ; 24(11)2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38894191

RESUMO

This article discusses the use of distributed acoustic sensing (DAS) for monitoring gas-liquid two-phase slug flow in horizontal pipes, using standard telecommunication fiber optics connected to a DAS integrator for data acquisition. The experiments were performed in a 14 m long, 5 cm diameter transparent PVC pipe with a fiber cable helically wrapped around the pipe. Using mineral oil and compressed air, the system captured various flow rates and gas-oil ratios. New algorithms were developed to characterize slug flow using DAS data, including slug frequency, translational velocity, and the lengths of slug body, slug unit, and the liquid film region that had never been discussed previously. This study employed a high-speed camera next to the fiber cable sensing section for validation purposes and achieved a good correlation among the measurements under all conditions tested. Compared to traditional multiphase flow sensors, this technology is non-intrusive and offers continuous, real-time measurement across long distances and in harsh environments, such as subsurface or downhole conditions. It is cost-effective, particularly where multiple measurement points are required. Characterizing slug flow in real time is crucial to many industries that suffer slug-flow-related issues. This research demonstrated the DAS's potential to characterize slug flow quantitively. It will offer the industry a more optimal solution for facility design and operation and ensure safer operational practices.

4.
Chem Biodivers ; 20(6): e202300068, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37102636

RESUMO

Atractylodes macrocephala Koidz. (AM) is a Chinese herbal medicine that is widely used for treating gastrointestinal diseases. However, little research has focused on it as a single medicine for treating gastric ulcers. Honey-bran stir-frying is a characteristic method of concocting AM, so we speculated that AM is more effective after this preparation process. Analysis by ultra-high-performance liquid chromatography-hybrid quadrupole-Orbitrap high-resolution mass spectrometry revealed changes in the chemical composition of raw Atractylodes (SG), bran-fried Atractylodes (FG), and honey-bran-fried Atractylodes (MFG). MFG was superior to SG and FG in improving the pathological structure of gastric tissue in rats with acute gastric ulcers, reducing inflammatory cell infiltration in gastric tissue, and significantly reducing malondialdehyde while increasing superoxide dismutase and glutathione peroxidase, and reducing the damage caused by free radical accumulation in the gastric mucosa. In addition, MFG reduced the expression of matrix metalloproteinase-9 (MMP-9), an inhibitor of metalloproteinase-1 (TIMP-1) and nuclear factor kappa-B (NF-κB)proteins, inhibited inflammatory response, and regulated the degradation and rebalancing of the extracellular matrix. Fecal microbiota analysis also revealed that MFG normalized the intestinal flora to some extent. Our study shows that AM had a protective effect on rats with alcohol-induced acute gastric ulcers before and after processing, and AM-processed products were more effective than raw ones. Compared with MF, MFG had a higher rate of ulcer inhibition and a stronger anti-inflammatory effect, and its mechanism of action was related to the NF-κB-MMP-9/TIMP-1 signaling pathway.


Assuntos
Atractylodes , Microbioma Gastrointestinal , Úlcera Gástrica , Ratos , Animais , NF-kappa B/metabolismo , Atractylodes/química , Metaloproteinase 9 da Matriz , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/prevenção & controle , Inibidor Tecidual de Metaloproteinase-1
5.
Sensors (Basel) ; 22(3)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35162010

RESUMO

Slug flow is one of the most common flow types encountered in surface facilities, pipelines, and wellbores. The intermittent gas phase, in the form of a Taylor bubble, followed by the liquid phase can be destructive to equipment. However, commonly used point flow sensors have significant limitations for flow analysis. Distributed acoustic sensing (DAS) can turn optical fibers into an array of distributed strain rate sensors and provide substantial insights into flow characterization. We built a 10 m vertical laboratory flow loop equipped with wrapped fiber optic cables to study the DAS response of rising Taylor bubbles. Low-passed DAS data allow for velocity tracking of Taylor bubbles of different sizes and water velocities. Moreover, we measured the velocity of the wake region following the Taylor bubble and explored the process of Taylor bubbles merging. The amplitude analysis of DAS data allows for the estimation of Taylor bubble size. We conclude that DAS is a promising tool for understanding Taylor bubble properties in a laboratory environment and monitoring destructive flow in facilities across different industries to ensure operations are safe and cost-effective.


Assuntos
Fibras Ópticas , Água , Acústica
6.
Am J Emerg Med ; 50: 784-788, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34879503

RESUMO

INTRODUCTION: It is not well established to use vitamin D supplementation for migraine, and this meta-analysis aims to explore the efficacy of vitamin D for migraine patients. METHODS: PubMed, EMbase, Web of science, EBSCO and Cochrane library databases were systematically searched up to May 2021, and we included randomized controlled trials (RCTs) exploring the effect of vitamin D for migraine patients. RESULTS: Six RCTs and 301 patients were included in the meta-analysis. Compared with control group in migraine patients, vitamin D supplementation could remarkably decrease headache attacks per month (MD = -2.74; 95% CI = -3.82 to -1.67; P < 0.00001), headache days per month (MD = -1.56; 95% CI = -2.44 to -0.68; P = 0.0005) and MIDAS score (MD = -5.72; 95% CI = -10.90 to -0.54; P = 0.03), but demonstrated no obvious influence on attack duration (MD = -2.20; 95% CI = -7.38 to 2.97; P = 0.40) or headache severity (MD = -0.56; 95% CI = -1.18 to 0.06; P = 0.08). CONCLUSIONS: Vitamin D supplementation provided additional benefits to treat migraine.


Assuntos
Suplementos Nutricionais , Transtornos de Enxaqueca/tratamento farmacológico , Vitamina D/uso terapêutico , Vitaminas/uso terapêutico , Humanos , Transtornos de Enxaqueca/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
7.
Acta Pharmacol Sin ; 41(2): 181-191, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31142800

RESUMO

Breast cancer resistance protein (BCRP) is one of ATP-binding cassette (ABC) transporters in brain microvessel endothelial cells that transport their substrates from brain to blood, thus limiting substrates to crossing into brain through blood-brain barrier. Our previous works show that bile duct ligation (BDL) impairs expression and function of brain BCRP in rats. Since zidovudine (AZT) is BCRP substrate, we investigated whether impaired expression and function of BCRP increased brain distribution and toxicity of AZT in BDL-D7 rats. After administration of AZT (10 mg/kg, i.v.), BDL markedly increased brain AZT concentrations, compared with sham-operated (SO) rats. The ratio of AZT brain-to-plasma area under concentration curve (AUC) in BDL rats was increased to 1.6-folds of SO rats. After treatment with AZT (100 mg/kg every day, i.v.) for 7 days, BDL significantly impaired cognitive functions compared with SO rats, evidenced by the significantly decreased percentage of alternation in Y-maze test and prolonged escaped latency in two-way passive avoidance trial. Furthermore, AZT treatment caused significant decrease in copies of mitochondrial DNA and mitochondrial membrane potential in hippocampus of BDL rats. Moreover, AZT treatment caused a significant decrease of cortex microtubule-associated protein 2 and hippocampus synaptophysin levels in BDL rats. AZT-induced CNS adverse alterations in BDL rats were not observed in SO rats treated with AZT. In conclusion, BDL decreases the function and expression of brain BCRP in rats, leading to increased brain distribution of AZT, which in turn enhances AZT CNS toxicity, leading to mitochondrial dysfunction, neuronal damage, and ultimately cognitive dysfunction.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Fármacos Anti-HIV/toxicidade , Encéfalo/efeitos dos fármacos , Zidovudina/toxicidade , Animais , Fármacos Anti-HIV/farmacocinética , Área Sob a Curva , Ductos Biliares/patologia , Barreira Hematoencefálica/metabolismo , Encéfalo/patologia , Linhagem Celular , Cognição/efeitos dos fármacos , Disfunção Cognitiva/induzido quimicamente , Cães , Humanos , Células Madin Darby de Rim Canino , Masculino , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual , Zidovudina/farmacocinética
8.
J Mol Cell Cardiol ; 135: 52-66, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31362020

RESUMO

(±)-Sodium5-bromo-2-(α-hydroxypentyl) benzoate (brand name: brozopine, BZP, 1a), derived from L-3-n-butylphthalide (L-NBP), has been reported to protect the brain from stoke and has been approved by CFDA in Phase I-II clinical trials. However, it remains to be investigated whether 1a may exhibit any cardioprotective effect on ischemia-reperfusion (I/R) injury. In the current study, C57BL/6 and ICR mice were pretreated with 1a, and myocardium I/R were then performed. We found that 1a not only significantly reduced the infarct size and improved cardiac contractile function after acute MI/R in both species, but also protected hearts from chronic MI-related cardiac injury. Mechanically, we found that 1a physically binds to 12/15-LOX-2 using molecular docking. The shRNA-mediated 12/15-LOX-2 knockdown almost completely blocked the protective effect of 1a. Our findings, for the first time, strongly indicate that 1a may serve as a potent and promising cardioprotective agent in treatment of I/R related injury, at least partially through targeting 12/15-LOX-2.


Assuntos
Araquidonato 15-Lipoxigenase/genética , Cardiotônicos/farmacologia , Infarto do Miocárdio/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Araquidonato 15-Lipoxigenase/efeitos dos fármacos , Benzoatos/farmacologia , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Coração/efeitos dos fármacos , Coração/fisiopatologia , Humanos , Masculino , Camundongos , Simulação de Acoplamento Molecular , Infarto do Miocárdio/patologia , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Ligação Proteica/efeitos dos fármacos , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia
9.
J Immunol ; 192(11): 5179-91, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24790152

RESUMO

B cell activation is regulated through the interplay of the BCR with the inhibitory coreceptor FcγRIIB and the activating coreceptor CD19. Recent studies suggest that Ag-driven BCR microclusters are efficiently converted to a signaling active state on colocalization with CD19 microclusters. Using total internal reflection fluorescence microscopy-based, high-resolution, high-speed live-cell and molecule imaging approaches, we show that when co-ligated to the BCR, the FcγRIIB can inhibit B cell activation by blocking the colocalization of BCR and CD19 microclusters within the B cell immunological synapse. Remarkably, this inhibitory function of FcγRIIB is dependent not on its well-characterized ITIM-containing cytoplasmic domain, but its transmembrane domain. Indeed, human primary B cells from systemic lupus erythematosus patients homozygous for gene encoding the loss-of-function transmembrane domain mutant FcγRIIB-I232T fail to block the synaptic colocalization of the BCR with CD19, leading to dysregulated recruitment of downstream signaling molecule p-PI3K to membrane proximal signalosome. This inhibitory function of FcγRIIB in impairing the spatial-temporal colocalization of BCR and CD19 microclusters in the B cell immunological synapse may help explain the hyper-reactive features of systemic lupus erythematosus patient B cells in reported studies. These observations may also provide new targets for therapies for systemic autoimmune disease.


Assuntos
Antígenos CD19/imunologia , Linfócitos B/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Ativação Linfocitária , Receptores de Antígenos de Linfócitos B/imunologia , Receptores de IgG/imunologia , Substituição de Aminoácidos , Animais , Antígenos CD19/genética , Linfócitos B/patologia , Humanos , Sinapses Imunológicas/genética , Sinapses Imunológicas/imunologia , Sinapses Imunológicas/patologia , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/patologia , Camundongos , Mutação de Sentido Incorreto , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/imunologia , Estrutura Terciária de Proteína , Receptores de Antígenos de Linfócitos B/genética , Receptores de IgG/genética
10.
J Immunol ; 190(9): 4661-75, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23554309

RESUMO

B lymphocytes are activated upon Ag sensing by BCRs. The substrate presenting the Ag can show different degrees of stiffness. It is not clear whether B cells can respond to changes in substrate stiffness. In this study we use high-resolution, high-speed live cell imaging techniques to capture the molecular events in B cell activation after the recognition of Ags tethered to polyacrylamide gel substrates with variable degrees of stiffness as quantified by Young's modulus (2.6-22.1 kPa). We show that the initiation of B cell activation is extremely sensitive to substrate stiffness. B cells exhibit much stronger activation responses when encountering Ags tethered to substrates with a high degree of stiffness as measured by the accumulation of BCR, phospho-spleen tyrosine kinase, and phosphotyrosine molecules into the B cell immunological synapse. Ags tethered to stiff substrates induce the formation of more prominent BCR and phospho-spleen tyrosine kinase microclusters with significantly enhanced colocalization as compared with Ags tethered to soft substrates. Moreover, the expression of the B cell activation marker CD69 is enhanced in B cells encountering Ags on stiffer substrates. Through time-lapse live cell imaging, we find that the different responses of B cells to substrate stiffness are only demonstrated 5 min after BCR and Ag recognition. Using a series of cytoskeleton inhibitors, we determine that the mechanosensing ability of B cells is dependent on microtubules, and only mildly linked to the actin cytoskeleton. These results suggest the importance of the mechanical properties mediated by substrate stiffness in B cell activation.


Assuntos
Apresentação de Antígeno/imunologia , Antígenos/imunologia , Linfócitos B/imunologia , Ativação Linfocitária/imunologia , Animais , Antígenos CD/imunologia , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos B/metabolismo , Citoesqueleto/imunologia , Citoesqueleto/metabolismo , Lectinas Tipo C/imunologia , Lectinas Tipo C/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Tirosina Quinases/imunologia , Proteínas Tirosina Quinases/metabolismo , Receptores de Antígenos de Linfócitos B/imunologia , Receptores de Antígenos de Linfócitos B/metabolismo
11.
Front Pharmacol ; 15: 1335786, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774211

RESUMO

Background: Polygonatum sibiricum (PS) is a traditional Chinese medicine (TCM) first recorded in Mingyi Bielu. The book documents that PS can nourish five internal organs, be taken for a long time, relax the body and prolong lifespan. Presently, PS is widely used in TCM to prevent premature graying of hair. Based on TCM theory and clinical trials, the wine steaming processed product from PS provides a better effect. However, no published study has elucidated the anti-aging mechanism. Purpose: The study aim was to investigate the anti-aging mechanism of PS and its wine steaming processed product in mice, specifically focusing on the effect of D-galactose (D-gal) surrounding the intestinal flora and the Kelch-like ECH-associated protein 1-nuclear factor erythroid 2-related factor 2-antioxidant response elements (Keap1/Nrf2/ARE) pathway. Methods: The chemical components in Raw PS (RPS) and Wine-steamed PS (WPS) were identified by ultra-performance liquid chromatography-hybrid quadrupole-Orbitrap high-resolution mass spectrometry (UPLC-Q-Orbitrap HRMS). An aging model using Kunming mice was established through intraperitoneally injected D-gal. Concentrations of RPS and WPS at 5, 10, or 15 g/kg/day levels were administered intragastrically, respectively. The body weight, liver and spleen indexes, superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and malondialdehyde (MDA) activities in serum and brain tissue were recorded. Hematoxylin and eosin (HE) stained brain tissue was histopathologically examined. The expressions of Keap1, Nrf2 and heme oxygenase 1 (HO-1) in the brain tissue at the mRNA and protein levels were respectively detected by reverse transcription-polymerase chain reaction (RT-PCR) and western blot (WB). Moreover, an Illumina Hiseq platform was used for 16S ribosomal RNA (16S rRNA) high-throughput sequencing to evaluate the proportions of intestinal flora in aging mice. Results: The proportions of saccharides, flavonoids, and triterpene acids were different between RPS and WPS. In the aging model mice, WPS outperformed RPS in improving body weight and mental state by increasing the spleen index, SOD and GSH-PX activities, decreasing the liver index and MDA activities, and restoring the histopathological morphology in D-gal-induced aging mice. At the mRNA levels, RPS and WPS significantly reduced the expression of Keap1 and increased the expressions of Nrf2 and HO-1. The trend in protein expressions was similar to that of the mRNA results, and WPS had a stronger effect than RPS. Fecal microbiota analysis showed that RPS and WPS restored intestinal microbiota proportions to normal levels. Conclusion: The results demonstrated that PS and its WPS had a positive effect in relieving oxidative stress in aging mice. WPS outperformed RPS, which might be related to the activation of the Keap1/Nrf2/ARE pathway and regulation of intestinal flora.

12.
Theriogenology ; 215: 249-258, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38103402

RESUMO

Sperm survival and activity depend on the provision of energy and nutrients from seminal plasma (SP). This study aimed to investigate the variations of metabolites within SP before and after freezing and subsequently explore the potential regulatory mechanisms affecting yak sperm cryodamage due to changes in metabolites in the SP. Untargeted metabolomics analysis was performed to screen for differential metabolites, followed by KEGG analysis to identify enriched signaling pathways. The combinatorial analysis of metabolomics and sperm proteomics revealed the influence of key SP metabolites on sperm proteins. Subsequently, the relevant differentially expressed proteins were verified by Western blot analysis. Finally, the mechanism underlying the positive effect of galactose on sperm motility was determined by assessing the change in ATP content in sperm before and after freezing and thawing. The data showed that a total of 425 and 269 metabolites were identified in the positive and negative ion modes, respectively. Freezing and thawing resulted in the up-regulation of 70 metabolites and the down-regulation of 29 metabolites in SP. The primary impact of freezing and thawing was observed in carbohydrate metabolism, including pyruvate metabolism, pentose phosphate pathway, galactose metabolism, the TCA cycle, and butanoate metabolism. In the combined analysis and Western blot results, a significant positive correlation was observed between galactose and Aldo-keto reductase family 1 member B1 (AKR1B1) (P < 0.05), which has the ability to convert galactose into galactol. Furthermore, the addition of galactose to thawed semen improved sperm motility by increasing AKR1B1 protein in sperm and was associated with the content of ATP. These data identify differential metabolites between fresh and frozen-thawed SP and suggest that galactose is a valuable additive for cryopreserved sperm, providing a theoretical basis for further exploration of the refrigerant formula for yak sperm cryopreservation.


Assuntos
Preservação do Sêmen , Sêmen , Masculino , Bovinos , Animais , Sêmen/fisiologia , Motilidade dos Espermatozoides , Galactose/farmacologia , Espermatozoides/fisiologia , Criopreservação/veterinária , Criopreservação/métodos , Congelamento , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Trifosfato de Adenosina
13.
Int J Biol Macromol ; 258(Pt 1): 128815, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38114010

RESUMO

First-line drugs for peptic ulcer (PU) treatment are typically limited by poor targeting and adverse effects associated with long-term use. Despite recent advancements in novel therapeutic approaches for PU, the development of sustained-release delivery systems tailored to specific pathological characteristics remains challenging. Persistent inflammation, particularly gastric inflammatory microenvironment imbalance, characterizes the PU. In this study, we prepared an in situ gel composed of sodium alginate, deacetylated gellan gum, calcium citrate, and Bletilla striata polysaccharide (BSP) to achieve sustained release of BSP. The BSP in situ gel demonstrated favorable fluidity in vitro and completed self-assembly in vivo in response to the acidic milieu at a pH of 1.5. Furthermore, the shear, extrusion, and deformation properties increased by 26.4 %, 103.7 %, and 46.3 %, respectively, with long-term gastric retention (4 h) and mucosal adaptation. Animal experiments confirmed that the BSP in situ gel could attenuate necrotic injury and inflammatory cell infiltration, maintain mucosal barrier integrity, regulate cytokine imbalance and inflammation-associated hyperapoptosis, thus effectively alleviate the inflammatory microenvironmental imbalance in PU without significant side effects. Overall, our findings demonstrated that the BSP in situ gel is a promising therapeutic strategy for PU and opens avenues for developing self-assembled formulations targeting the pathological features of PUs.


Assuntos
Orchidaceae , Úlcera Péptica , Animais , Alginatos/química , Ácido Gástrico , Polissacarídeos/química , Etanol , Inflamação , Orchidaceae/química
14.
Nat Commun ; 15(1): 2441, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499565

RESUMO

Lipid synthesis increases during the cell cycle to ensure sufficient membrane mass, but how insufficient synthesis restricts cell-cycle entry is not understood. Here, we identify a lipid checkpoint in G1 phase of the mammalian cell cycle by using live single-cell imaging, lipidome, and transcriptome analysis of a non-transformed cell. We show that synthesis of fatty acids in G1 not only increases lipid mass but extensively shifts the lipid composition to unsaturated phospholipids and neutral lipids. Strikingly, acute lowering of lipid synthesis rapidly activates the PERK/ATF4 endoplasmic reticulum (ER) stress pathway that blocks cell-cycle entry by increasing p21 levels, decreasing Cyclin D levels, and suppressing Retinoblastoma protein phosphorylation. Together, our study identifies a rapid anticipatory ER lipid checkpoint in G1 that prevents cells from starting the cell cycle as long as lipid synthesis is low, thereby preventing mitotic defects, which are triggered by low lipid synthesis much later in mitosis.


Assuntos
Lipídeos , Mitose , Animais , Ciclo Celular , Fase G1 , Fosforilação , Mamíferos
15.
J Pharm Anal ; 14(1): 52-68, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38352949

RESUMO

The occurrence of benign prostate hyperplasia (BPH) was related to disrupted sex steroid hormones, and metformin (Met) had a clinical response to sex steroid hormone-related gynaecological disease. However, whether Met exerts an antiproliferative effect on BPH via sex steroid hormones remains unclear. Here, our clinical study showed that along with prostatic epithelial cell (PEC) proliferation, sex steroid hormones were dysregulated in the serum and prostate of BPH patients. As the major contributor to dysregulated sex steroid hormones, elevated dihydrotestosterone (DHT) had a significant positive relationship with the clinical characteristics of BPH patients. Activation of adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) by Met restored dysregulated sex steroid hormone homeostasis and exerted antiproliferative effects against DHT-induced proliferation by inhibiting the formation of androgen receptor (AR)-mediated Yes-associated protein (YAP1)-TEA domain transcription factor (TEAD4) heterodimers. Met's anti-proliferative effects were blocked by AMPK inhibitor or YAP1 overexpression in DHT-cultured BPH-1 cells. Our findings indicated that Met would be a promising clinical therapeutic approach for BPH by inhibiting dysregulated steroid hormone-induced PEC proliferation.

16.
Theriogenology ; 200: 60-69, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36764186

RESUMO

Sperm cryopreservation is one of the most effective methods for the conservation of germplasm resources and used of superior sires widely. However, the motility of yak (Bos grunniens) sperm was low after thawing and the proteomics changes in sperm cryopreservation remain unknown. Therefore, the aim of this study was to explore the differences between fresh sperm and frozen sperm of yak through the proteomic analysis and thus improve the understanding of sperm cryodamage. The Tandem Mass Tags (TMT) technology was used to screen differentially expressed proteins (DEPs) before and after freezing. Then, GO and KEGG analysis were conducted to analyze the DEPs enriched signaling pathways. Finally, the DEPs, including superoxide dismutase 1 (SOD1) and NADH ubiquinone oxidoreductase core subunit S8 (NDUFS8) were verified by the immunofluorescence technique. The results showed that there were 229 DEPs between fresh and frozen-thawed yak sperm. Compared with the fresh sperm, 120 proteins were up-regulated and 109 proteins were down-regulated in frozen-thawed sperm. The GO annotation showed that the up-regulated proteins enriched in metabolic and cytoskeleton-related processes, including lipoprotein metabolic process, lipid transport, extracellular region and intermediate filament cytoskeleton organization. In contrast, the down-regulated proteins enriched in biological processes including single fertilization, sperm capacitation and response to unfolded protein. KEGG pathway analysis indicated that freezing and thawing affected the oxidative phosphorylation pathway, the fructose and mannose metabolic pathway and the glycerolipid metabolic pathway of yak sperm. Immunofluorescence results showed that the protein expression level of SOD1 protein in the frozen group was significantly lower than that in the fresh group (P < 0.01), and the protein expression level of NDUFS8 protein was significantly higher in frozen group (P < 0.01). This study revealed the DEPs between fresh and frozen-thawed sperm and provides a theoretical basis to further explore the exertion of normal biological functions of yak sperm after freezing and thawing.


Assuntos
Proteômica , Preservação do Sêmen , Bovinos , Masculino , Animais , Congelamento , Sêmen , Espermatozoides/metabolismo , Criopreservação/métodos , Criopreservação/veterinária , Motilidade dos Espermatozoides , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária
17.
Int J Gynaecol Obstet ; 161(3): 1069-1074, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36572390

RESUMO

OBJECTIVE: To explore the interactions between cervical length (CL) and placenta accreta spectrum (PAS) on severe postpartum hemorrhage (SPPH) in patients with placenta previa. METHODS: A retrospective case-control study was conducted at four medical centers in China, and 588 patients with placenta previa were included. The logistic regression analysis and restricted cubic splines (RCS) were used to evaluate the association between CL and SPPH. Furthermore, the joint effect of CL and PAS on SPPH was assessed, and the additive and multiplicative interactions were calculated. RESULTS: After adjusting for potential confounders, the negative linear dose-response relationship was confirmed by RCS, and the change of odds ratio (OR) was more significant when CL was 2.5 cm or less. The risk of SPPH was significantly higher when CL of 2.5 cm or less co-existed with placenta increta/percreta than when CL of 2.5 cm less, or placenta increta/percreta existed alone (adjusted OR [aOR]CL ≤2.5cm&placenta accreta/non-PAS 3.40, 95% confidence interval [CI] 1.37-8.45; aORplacenta increta/percreta&CL >2.5cm 4.75, 95% CI 3.03-7.47; aORCL ≤2.5cm&placenta increta/percreta 14.51, 95% CI 6.08-34.64), and there might be additive interaction between CL and placenta increta/percreta on SPPH (attributable proportion due to interaction 50.7%, 95% CI 6.1%-95.3%). CONCLUSION: If CL was routinely performed during PAS evaluation, the increased OR of short CL and PAS could allow better patient preparation through counseling.


Assuntos
Placenta Acreta , Placenta Prévia , Hemorragia Pós-Parto , Gravidez , Humanos , Feminino , Placenta Acreta/diagnóstico por imagem , Placenta Prévia/diagnóstico por imagem , Estudos Retrospectivos , Estudos de Casos e Controles , Hemorragia Pós-Parto/diagnóstico por imagem , Hemorragia Pós-Parto/etiologia , Placenta
18.
ChemSusChem ; 15(23): e202201625, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36184569

RESUMO

The electrochemical transformation of biomass to high value-added products is attractive. Herein, Cu sulfide-mediated in-situ synthesis of Cu oxide was achieved for efficient electro-oxidation of biomass derived 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA). The copper foam-supported Cu sulfide (Cu-S/CF) was in-situ converted to Cu oxide during the electro-oxidation process. The in-situ formed Cu oxide presented high HMF conversion, FDCA yield, and faradaic efficiency in 1 m KOH with HMF concentration up to 100 mm. The oxidation of HMF on Cu oxide started with the formation of high-valence Cu species with the assistance of OH- , which then oxidized HMF spontaneously. An anion exchange membrane (AEM) electrolyzer with Cu-S/CF as the anode was assembled to continuously produce FDCA with H2 generation at the cathode. The AEM electrolyzer ran stably for 60 h with FDCA content higher than 85 % at a cell voltage between 1.50 and 1.60 V.


Assuntos
Óxidos , Sulfetos
19.
Cell Rep ; 36(4): 109436, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34320337

RESUMO

Contact inhibition of cell proliferation regulates tissue size and prevents uncontrolled cell expansion. When cell density increases, contact inhibition can force proliferating cells into quiescence. Here we show that the variable memory of local cell density experienced by a mother cell controls the levels of the cyclin-dependent kinase (CDK) activator cyclin D1 and inhibitor p27 in newborn daughters, which direct cells to proliferation or quiescence. Much of this regulation can be explained by rapid suppression of ERK activity by high cell density in mothers, which leads to lower cyclin D1 and higher p27 levels in daughters. Strikingly, cell density and mitogen signals compete by shifting the ratio of cyclin D1/p27 levels below or above a single sharp threshold that controls the proliferation decision. Thus, the history of competing cell density and mitogen signals experienced by mothers is funneled into a precise activator-inhibitor balance that decides the fate of daughter cells.


Assuntos
Ciclo Celular/genética , Contagem de Células , Ciclina D1/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Feminino , Humanos , Sistema de Sinalização das MAP Quinases , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Mitógenos/metabolismo , Modelos Biológicos , Fosforilação , Proteína do Retinoblastoma/metabolismo
20.
J Cell Biol ; 220(8)2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34037657

RESUMO

After two converging DNA replication forks meet, active replisomes are disassembled and unloaded from chromatin. A key process in replisome disassembly is the unloading of CMG helicases (CDC45-MCM-GINS), which is initiated in Caenorhabditis elegans and Xenopus laevis by the E3 ubiquitin ligase CRL2LRR1. Here, we show that human cells lacking LRR1 fail to unload CMG helicases and accumulate increasing amounts of chromatin-bound replisome components as cells progress through S phase. Markedly, we demonstrate that the failure to disassemble replisomes reduces the rate of DNA replication increasingly throughout S phase by sequestering rate-limiting replisome components on chromatin and blocking their recycling. Continued binding of CMG helicases to chromatin during G2 phase blocks mitosis by activating an ATR-mediated G2/M checkpoint. Finally, we provide evidence that LRR1 is an essential gene for human cell division, suggesting that CRL2LRR1 enzyme activity is required for the proliferation of cancer cells and is thus a potential target for cancer therapy.


Assuntos
Proliferação de Células , Montagem e Desmontagem da Cromatina , DNA/biossíntese , Proteínas Repressoras/metabolismo , Fase S , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem/genética , Quinase 1 do Ponto de Checagem/metabolismo , DNA/genética , DNA Helicases/genética , DNA Helicases/metabolismo , Humanos , Microscopia de Fluorescência , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Ligação Proteica , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas Repressoras/genética , Fatores de Tempo
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