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1.
EMBO J ; 42(20): e113743, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37661833

RESUMO

Mitochondria play essential roles in cancer cell adaptation to hypoxia, but the underlying mechanisms remain elusive. Through mitochondrial proteomic profiling, we here find that the prolyl hydroxylase EglN1 (PHD2) accumulates on mitochondria under hypoxia. EglN1 substrate-binding region in the ß2ß3 loop is responsible for its mitochondrial translocation and contributes to breast tumor growth. Furthermore, we identify AMP-activated protein kinase alpha (AMPKα) as an EglN1 substrate on mitochondria. The EglN1-AMPKα interaction is essential for their mutual mitochondrial translocation. After EglN1 prolyl-hydroxylates AMPKα under normoxia, they rapidly dissociate following prolyl-hydroxylation, leading to their immediate release from mitochondria. In contrast, hypoxia results in constant EglN1-AMPKα interaction and their accumulation on mitochondria, leading to the formation of a Ca2+ /calmodulin-dependent protein kinase 2 (CaMKK2)-EglN1-AMPKα complex to activate AMPKα phosphorylation, ensuring metabolic homeostasis and breast tumor growth. Our findings identify EglN1 as an oxygen-sensitive metabolic checkpoint signaling hypoxic stress to mitochondria through its ß2ß3 loop region, suggesting a potential therapeutic target for breast cancer.


Assuntos
Proteínas Quinases Ativadas por AMP , Neoplasias da Mama , Feminino , Humanos , Proteínas Quinases Ativadas por AMP/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Hipóxia , Prolina Dioxigenases do Fator Induzível por Hipóxia/genética , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Mitocôndrias/metabolismo , Proteômica
2.
Cell ; 147(2): 447-58, 2011 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-22000021

RESUMO

Spinal opioid-induced itch, a prevalent side effect of pain management, has been proposed to result from pain inhibition. We now report that the µ-opioid receptor (MOR) isoform MOR1D is essential for morphine-induced scratching (MIS), whereas the isoform MOR1 is required only for morphine-induced analgesia (MIA). MOR1D heterodimerizes with gastrin-releasing peptide receptor (GRPR) in the spinal cord, relaying itch information. We show that morphine triggers internalization of both GRPR and MOR1D, whereas GRP specifically triggers GRPR internalization and morphine-independent scratching. Providing potential insight into opioid-induced itch prevention, we demonstrate that molecular and pharmacologic inhibition of PLCß3 and IP3R3, downstream effectors of GRPR, specifically block MIS but not MIA. In addition, blocking MOR1D-GRPR association attenuates MIS but not MIA. Together, these data suggest that opioid-induced itch is an active process concomitant with but independent of opioid analgesia, occurring via the unidirectional cross-activation of GRPR signaling by MOR1D heterodimerization.


Assuntos
Analgesia , Analgésicos Opioides/administração & dosagem , Morfina/administração & dosagem , Dor/tratamento farmacológico , Prurido/induzido quimicamente , Receptores da Bombesina/metabolismo , Receptores Opioides mu/metabolismo , Sequência de Aminoácidos , Animais , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Receptores da Bombesina/genética , Receptores Opioides mu/genética , Transdução de Sinais
3.
Am J Pathol ; 194(5): 693-707, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38309428

RESUMO

Glucose lowering independently reduces liver fibrosis in human nonalcoholic fatty liver disease. This study investigated the impact of diabetes on steatohepatitis and established a novel mouse model for diabetic steatohepatitis. Male C57BL/6J mice were fed a 60% high-fat diet (HFD) and injected with carbon tetrachloride (CCl4) and streptozotocin (STZ) to induce diabetes. The HFD+CCl4+STZ group showed more severe liver steatosis, hepatocyte ballooning, and regenerative nodules compared with other groups. Diabetes up-regulated inflammatory cytokine-associated genes and increased the M1/M2 macrophage ratios in the liver. Single-cell RNA sequencing analysis of nonparenchymal cells in the liver showed that diabetes reduced Kupffer cells and increased bone marrow-derived recruited inflammatory macrophages, such as Ly6Chi-RM. Diabetes globally reduced liver sinusoidal endothelial cells (LSECs). Furthermore, genes related to the receptor for advanced glycation end products (RAGE)/Toll-like receptor 4 (TLR4) were up-regulated in Ly6Chi-RM and LSECs in mice with diabetes, suggesting a possible role of RAGE/TLR4 signaling in the interaction between inflammatory macrophages and LSECs. This study established a novel diabetic steatohepatitis model using a combination of HFD, CCl4, and STZ. Diabetes exacerbated steatosis, hepatocyte ballooning, fibrosis, regenerative nodule formation, and the macrophage M1/M2 ratios triggered by HFD and CCl4. Single-cell RNA sequencing analysis indicated that diabetes activated inflammatory macrophages and impairs LSECs through the RAGE/TLR4 signaling pathway. These findings open avenues for discovering novel therapeutic targets for diabetic steatohepatitis.


Assuntos
Diabetes Mellitus , Hepatopatia Gordurosa não Alcoólica , Camundongos , Masculino , Humanos , Animais , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Células Endoteliais/metabolismo , Transcriptoma , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Cirrose Hepática/patologia , Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Dieta Hiperlipídica/efeitos adversos
4.
J Pharmacol Exp Ther ; 385(1): 5-16, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36328485

RESUMO

Ubiquitin-proteasome dysfunction contributes to obesity-related metabolic disorders, such as diabetes and fatty liver disease. However, the regulation of ubiquitin-proteasome activity by insulin remains to be elucidated. Here, we show that prolonged insulin stimulation activates proteasome function even though it reduces the ubiquitinated proteins in H4IIEC3 hepatocytes. Looking for a pathway by which insulin inhibits ubiquitination, we found that hepatic expression of ubiquitin-specific protease 14 (USP14) was upregulated in the liver of patients with insulin resistance. Indeed, the USP14-specific inhibitor IU1 canceled the insulin-mediated reduction of ubiquitinated proteins. Furthermore, insulin-induced endoplasmic reticulum (ER) stress, which was canceled by IU1, suggesting that USP14 activity is involved in insulin-induced ER stress. Co-stimulation with insulin and IU1 for 2 hours upregulated the nuclear translocation of the lipogenic transcription factor, sterol regulatory element binding protein-1c (SREBP-1c), upregulated the expression of the lipogenic gene, fatty acid synthase (Fasn), and repressed the gluconeogenic genes. In conclusion, insulin activates proteasome function even though it inhibits protein ubiquitination by activating USP14 in hepatocytes. USP14 activation by insulin inhibits mature SREBP-1c while upregulating ER stress and the expression of genes involved in gluconeogenesis. Further understanding mechanisms underlying the USP14 activation and its pleiotropic effects may lead to therapeutic development for obesity-associated metabolic disorders, such as diabetes and fatty liver disease. SIGNIFICANCE STATEMENT: This study shows that insulin stimulation inhibits ubiquitination by activating USP14, independent of its effect on proteasome activity in hepatocytes. USP14 also downregulates the nuclear translocation of the lipogenic transcription factor SREBP-1c and upregulates the expression of genes involved in gluconeogenesis. Since USP14 is upregulated in the liver of insulin-resistant patients, understanding mechanisms underlying the USP14 activation and its pleiotropic effects will help develop treatments for metabolic disorders such as diabetes and fatty liver.


Assuntos
Hepatócitos , Hepatopatia Gordurosa não Alcoólica , Complexo de Endopeptidases do Proteassoma , Proteína de Ligação a Elemento Regulador de Esterol 1 , Humanos , Enzimas Desubiquitinantes/genética , Enzimas Desubiquitinantes/metabolismo , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Insulina/farmacologia , Insulina/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/genética , Obesidade/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/farmacologia , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Proteases Específicas de Ubiquitina/genética , Proteases Específicas de Ubiquitina/metabolismo , Proteases Específicas de Ubiquitina/farmacologia , Proteínas Ubiquitinadas/genética , Proteínas Ubiquitinadas/metabolismo , Proteínas Ubiquitinadas/farmacologia , Ubiquitinação , Ubiquitinas/genética , Ubiquitinas/metabolismo , Ubiquitinas/farmacologia
5.
Macromol Rapid Commun ; 44(3): e2200657, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36128639

RESUMO

Recent years have witnessed the rapid development of self-healing and recyclable materials because they can extend the life of the material. For polysiloxane materials, exploring polysiloxanes with high-strength and self-healing properties remains a challenge. In this work, a high-strength and self-healing polysiloxane containing N-acetyl-L-cysteine (NACL) side groups is prepared. The NACL is used to form strong hydrogen bonds to build a self-healing network. Molecular simulations help explain the reasons and processes for the repair of modified polysiloxanes. On the one hand, the obtained modified polysiloxanes have good self-healing properties. The self-healing efficiency of modified polysiloxane can reach 96.9%. As the number of NACL increases, the tensile strength of the modified polysiloxane increases. For PMVS-30%NACL, the tensile strength can reach 4.36 MPa, and the strain can reach 586%. On the other hand, modified polysiloxane has an apparent inhibitory effect on Staphylococcus aureus. With the increase in the number of NACL, the antibacterial effect of modified polysiloxane is more obvious. Furthermore, NACL is a bio-based amino acid with excellent biocompatibility. This work expands the idea of designing and synthesizing high-strength polysiloxanes with antibacterial properties. It has great potential in the field of polysiloxane antimicrobial coatings.


Assuntos
Aminoácidos , Siloxanas , Siloxanas/química , Ligação de Hidrogênio , Cloreto de Sódio , Antibacterianos/química , Acetilcisteína
6.
Endocr J ; 69(8): 907-918, 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-35321982

RESUMO

Selenoprotein P is upregulated in type 2 diabetes, causing insulin and exercise resistance. We have previously reported that eicosapentaenoic acid (EPA) negatively regulates Selenop expression by suppressing Srebf1 in H4IIEC3 hepatocytes. However, EPA downregulated Srebf1 long before downregulating Selenop. Here, we report additional novel mechanisms for the Selenop gene regulation by EPA. EPA upregulated Foxo1 mRNA expression, which was canceled with the ERK1/2 inhibitor, but not with the PKA inhibitor. Foxo1 knockdown by siRNA initiated early suppression of Selenop, but not Srebf1, by EPA. However, EPA did not affect the nuclear translocation of the FoxO1 protein. Neither ERK1/2 nor PKA inhibitor affected FoxO1 nuclear translocation. In summary, FoxO1 knockdown accelerates the EPA-mediated Selenop downregulation independent of SREBP-1c in hepatocytes. EPA upregulates Foxo1 mRNA via the ERK1/2 pathway without altering its protein and nuclear translocation. These findings suggest redundant and conflicting transcriptional networks in the lipid-induced redox regulation.


Assuntos
Diabetes Mellitus Tipo 2 , Ácido Eicosapentaenoico , Regulação para Baixo , Proteína Forkhead Box O1 , Hepatócitos , Humanos , Insulina , RNA Mensageiro , Selenoproteína P , Proteína de Ligação a Elemento Regulador de Esterol 1 , Esteróis
7.
Plant Physiol ; 183(3): 1184-1199, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32321843

RESUMO

Plant height and leaf angle are two crucial determinants of plant architecture in maize (Zea mays) and are closely related to lodging resistance and canopy photosynthesis at high planting density. These two traits are primarily regulated by several phytohormones. However, the mechanism of ethylene in regulating plant architecture in maize, especially plant height and leaf angle, is unclear. Here, we characterized a maize mutant, Semidwarf3 (Sdw3), which exhibits shorter stature and larger leaf angle than the wild type. Histological analysis showed that inhibition of longitudinal cell elongation in the internode and promotion in the auricle were mainly responsible for reduced plant height and enlarged leaf angle in the Sdw3 mutant. Through positional cloning, we identified a transposon insertion in the candidate gene ZmACS7, encoding 1-aminocyclopropane-1-carboxylic acid (ACC) Synthase 7 in ethylene biosynthesis of maize. The transposon alters the C terminus of ZmACS7. Transgenic analysis confirmed that the mutant ZmACS7 gene confers the phenotypes of the Sdw3 mutant. Enzyme activity and protein degradation assays indicated that the altered C terminus of ZmACS7 in the Sdw3 mutant increases this protein's stability but does not affect its catalytic activity. The ACC and ethylene contents are dramatically elevated in the Sdw3 mutant, leading to reduced plant height and increased leaf angle. In addition, we demonstrated that ZmACS7 plays crucial roles in root development, flowering time, and leaf number, indicating that ZmACS7 is an important gene with pleiotropic effects during maize growth and development.


Assuntos
Vias Biossintéticas/genética , Etilenos/biossíntese , Genes de Plantas , Zea mays/anatomia & histologia , Sequência de Aminoácidos , Sequência de Bases , Regulação da Expressão Gênica de Plantas , Liases/genética , Liases/metabolismo , Mutação/genética , Fenótipo , Folhas de Planta/anatomia & histologia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/anatomia & histologia , Domínios Proteicos , Estabilidade Proteica , Sementes/crescimento & desenvolvimento , Transcriptoma/genética , Zea mays/genética
8.
Dermatol Ther ; 34(2): e14866, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33570237

RESUMO

Accumulating evidence suggests that botulinum neurotoxins (BoNTs), which inhibit acetylcholine release, can be used for treating plaque psoriasis. The therapeutic effects of scopolamine occur through antagonism of central muscarinic acetylcholine receptors. Thus, scopolamine has potential for the treatment of psoriasis. We aimed to evaluate the efficacy and safety of scopolamine plus propofol for the treatment of recalcitrant psoriasis. Twelve patients with recalcitrant psoriasis were enrolled. Patients received intravenous injection of scopolamine plus propofol for 5 consecutive days per month for a total of 3 months. Clinical efficacy was evaluated using a Psoriasis Area and Severity Index (PASI) score. Efficacy outcome was ≥75% reduction in PASI score (PASI75) from baseline. Two patients were lost to follow-up. At week 8, two of 10 patients (20%) achieved PASI75, and at week 12, seven of 10 (70%) achieved PASI75. Treatment was well tolerated, with no reported adverse events. Our study revealed the efficacy and safety of scopolamine plus propofol for the treatment of recalcitrant psoriasis. Scopolamine plus propofol therapy may be a new treatment for recalcitrant psoriasis.


Assuntos
Propofol , Psoríase , Escopolamina/uso terapêutico , Humanos , Projetos Piloto , Propofol/uso terapêutico , Psoríase/diagnóstico , Psoríase/tratamento farmacológico , Índice de Gravidade de Doença , Resultado do Tratamento
9.
Molecules ; 25(12)2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32549376

RESUMO

Volatile organic compounds (VOCs) from polypropylene (PP) seriously restricts the application of PP in an automotive field. Herein, the traceability of VOCs from PP resins during manufacturing process and accelerated photoaging degradation was clarified on basis of an accurate characterization method of key VOCs. The influence of PP structures on changing the accelerated photoaging degradation on the VOCs was systematic. The VOCs were identified by means of Gas chromatography (GC) coupled with both a hydrogen flame ion detector (FID) and a mass spectrometry detector (MSD). Results showed that both the molecular structure of PP and the manufacturing process affected the species and contents of VOCs. In addition, the photoaging degradation of PP resulted in a large number of new emerged volatile carbonyl compounds. Our work proposed a possible VOC formation mechanism during the manufacturing and photoaging process. VOCs from PP resins were originated from oligomers and chain random scission during thermomechanical degradation. However, ß scission of alkoxy radical and Norrish tape I reactions of ketones via intermediate transition were probably the main VOCs formation routes towards PP during photoaging degradation. This work could provide scientific knowledge on both the accurate traceability of VOCs emissions and new technology for development of low-VOCs PP composites for vehicle.


Assuntos
Resinas Sintéticas/química , Compostos Orgânicos Voláteis/química , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Oxirredução , Ozônio/química , Polipropilenos/química , Fatores de Tempo , Compostos Orgânicos Voláteis/análise
10.
Langmuir ; 35(26): 8692-8698, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31181884

RESUMO

Silica aerogels, which are constructed with silica nanoparticles and numerous nanoscale pores, have many outstanding attributes, but they are usually brittle and hydrophilic. For the construction of a robust aerogel, the novel polyhedral oligomeric silsesquioxane (POSS) was introduced to prepare a series of aerogels possessing particles covered with elastic cushion to improve the mechanical property. The multialkoxy POSS, which possessed stiff Si-O-Si nanocages and flexible alkyl chains, was synthesized via thiol-ene click chemistry. After a facile and efficient approach, a partially ordered structure of SiO2 nanoparticles and organic elastic cushion would form spontaneously within the aerogels. With the POSS as the only precursor, several outstanding attributes were achieved in a single aerogel such as high specific surface area (SSA), high compression strength, high compression modulus, and noticeable compression flexibility. Meanwhile, the aerogel was superhydrophobic of which the contact angle (CA) was higher than 153°. Moreover, the potential application of oil-water separation is also presented.

11.
Biochemistry ; 57(51): 6997-7010, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30422629

RESUMO

Diacylglycerol acyltransferase 2 (DGAT2) catalyzes the final step in triacylglycerol (TAG) synthesis. Genetic knockdown or pharmacological inhibition of DGAT2 leads to a decrease in very-low-density lipoprotein TAG secretion and hepatic lipid levels in rodents, indicating DGAT2 may represent an attractive therapeutic target for treatment of hyperlipidemia and hepatic steatosis. We have previously described potent and selective imidazopyridine DGAT2 inhibitors with high oral bioavailability. However, the detailed mechanism of DGAT2 inhibition has not been reported. Herein, we describe imidazopyridines represented by PF-06424439 (1) and 2 as long residence time inhibitors of DGAT2. We demonstrate that 1 and 2 are slowly reversible, time-dependent inhibitors, which inhibit DGAT2 in a noncompetitive mode with respect to the acyl-CoA substrate. Detailed kinetic analysis demonstrated that 1 and 2 inhibit DGAT2 in a two-step binding mechanism, in which the initial enzyme-inhibitor complex (EI) undergoes an isomerization step resulting in a much higher affinity complex (EI*) with overall apparent inhibition constants ( Ki*app values) of 16.7 and 16.0 nM for 1 and 2, respectively. The EI* complex dissociates with dissociation half-lives of 1.2 and 1.0 h for 1 and 2, respectively. A binding assay utilizing 125I-labeled imidazopyridine demonstrated that the level of imidazopyridine binding to DGAT2 mutant enzymes, H161A and H163A, dramatically decreased to 11-17% of that of the wild-type enzyme, indicating that these residues are critical for imidazopyridines to bind to DGAT2. Taken together, imidazopyridines may thus represent a promising lead series for the development of DGAT2 inhibitors that display an unprecedented combination of potency, selectivity, and in vivo efficacy.


Assuntos
Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Diacilglicerol O-Aciltransferase/metabolismo , Substituição de Aminoácidos , Animais , Domínio Catalítico/genética , Diacilglicerol O-Aciltransferase/genética , Desenho de Fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos , Imidazóis/química , Imidazóis/farmacologia , Cinética , Mutagênese Sítio-Dirigida , Piridinas/química , Piridinas/farmacologia , Ensaio Radioligante , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Células Sf9 , Spodoptera
12.
J Immunol ; 195(10): 4802-9, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26475925

RESUMO

Diverse clinical factors, including intestinal ischemia, contribute to acute lung injury (ALI), which has up to a 40% mortality rate. During the development of lung injury an immune response is elicited that exacerbates the lung insult. Neutrophils have been well studied in mediating the pulmonary insults through an assortment of mechanisms, such as release of granule contents and production of proinflammatory cytokines due to the overactivation of complement and cytokines. In this study, we found that enhanced endoplasmic reticulum (ER) stress was observed in infiltrated neutrophils in the early stage of an ALI mice model. In neutrophils, complement 5a (C5a) inspires strong ER stress through inositol-requiring kinase 1a and, to a less extent, the protein kinase R-like ER kinase signaling pathway. The granule release induced by C5a was ER stress mediated. Knowkdown of X-box-binding protein 1, a downstream signaling molecule of inositol-requiring kinase 1a, impaired granule release, based on myeloperoxidase production. Further analysis revealed that C5a induced ER stress by binding to C5a receptor in neutrophils. Using xbp(f/f) MRP8-cre mice in which X-box-binding protein 1 is deficient specifically in neutrophils and ER stress is deprived, we confirmed that ER stress in neutrophils was required for granule release in vivo and led to ALI, whereas dampening ER stress in neutrophils substantially alleviated ALI. Taken together, our results demonstrated that C5a receptor-mediated ER stress induced granule release in neutrophils, contributing to the development of ALI. This novel mechanism suggests a new potential therapeutic target in autophagy regulation for ALI.


Assuntos
Lesão Pulmonar Aguda/imunologia , Estresse do Retículo Endoplasmático/imunologia , Pulmão/imunologia , Neutrófilos/imunologia , Traumatismo por Reperfusão/imunologia , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/patologia , Animais , Complemento C5a/genética , Complemento C5a/metabolismo , Estresse do Retículo Endoplasmático/genética , Endorribonucleases/genética , Endorribonucleases/imunologia , Pulmão/patologia , Camundongos , Camundongos Transgênicos , Neutrófilos/patologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/imunologia , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia
13.
Cell Physiol Biochem ; 36(4): 1331-45, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26159215

RESUMO

BACKGROUND: Preconditioning with the volatile anesthetic isoflurane exerts protective effects in animal models of ischemia. The cytoprotective effects of isoflurane are dependent on the expression of hypoxia inducible factor-1 (HIF-1), a dimeric transcription factor that mediates cellular responses to hypoxia. METHODS: We investigated the effect of isoflurane preconditioning on bone marrow stromal cell (BMSC) survival and function. RESULTS: Short exposures to low isoflurane concentrations promoted in vitro survival and migration of BMSCs, whereas long exposures and high doses had the opposite effect. At specific doses and times, isoflurane upregulated the expression of HIF-1α and the stromal-derived factor-1 receptor CXCR4, and induced the activation of Akt, similar to hypoxia, and the effect of isoflurane was abrogated by silencing of HIF-1α or inhibition of PI3K/Akt signaling. In vivo experiments showed that isoflurane preconditioning increased the engraftment of BMSCs into the ischemic brain and improved functional recovery in a mouse model of stroke. CONCLUSION: Isoflurane preconditioning at specific doses and times improves the survival and function of BMSCs through the upregulation of CXCR4 via a mechanism involving HIF-1α expression and the PI3K/Akt pathway, suggesting that anesthetic preconditioning could be developed as a strategy to improve the efficiency of cell therapy.


Assuntos
Anestésicos Inalatórios/farmacologia , Isquemia Encefálica/terapia , Isoflurano/farmacologia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Receptores CXCR4/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
Macromol Rapid Commun ; 36(24): 2156-61, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26469185

RESUMO

The theoretical calculations are used to find that D-π-A-π-A style conjugated polymer PC-TBTBT is more efficient for solar cells application than the D-π-A analog PC-TBT because the D-π-A-π-A structure has a narrower band gap and higher molar absorption coefficient and redshift spectrum. Motivated by the theoretical prediction, 5,6-bis(octyloxy)-2,1,3-benzothiadiazole and 2,7-carbazole are adopted to synthesize the D-π-A-π-A style PC-TBTBT (M(w) = 31.1 kDa) and D-π-A analog PC-TBT (M(w) = 87.5 kDa) by Suzuki coupling reaction. Experimental results confirm that D-π-A-π-A PC-TBTBT-based solar cell shows a power conversion efficiency (PCE) of 4.74% with high V(OC) of 0.99 V and enhanced J(SC) of 9.70 mA cm(-2). The PCE and J(SC) achieve improvements of 17% and 26%, respectively, compared to the D-π-A PC-TBT-based solar cell.


Assuntos
Carbazóis/química , Polímeros/química , Polímeros/síntese química , Energia Solar , Tiadiazóis/química
15.
J Dermatol ; 51(5): 696-703, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38351540

RESUMO

Epidural block using lidocaine, a non-selective blocker of voltage-gated sodium channels (Nav), has demonstrated efficacy in the treatment of severe plaque psoriasis in a limited number of cases. This study aimed to evaluate the effectiveness and safety of epidural lidocaine block in adult patients with severe, treatment-resistant plaque psoriasis. This was an open-label pilot study. Patients with severe plaque-type psoriasis unresponsive to at least one systemic treatment were enrolled for a 1-week epidural lidocaine block and followed up for 48 weeks. Thirty-six patients participated, with 32 completing the study. At the 12-week mark, there was a remarkable 59% improvement in the mean Psoriasis Area Severity Index (PASI) score (P < 0.001). By week 48, 28 out of 32 patients (87%) achieved PASI 75, while 18 out of 32 (56%) reached PASI 90. Within 7 days, 20 out of 21 patients (95%) reported a reduction in itch, with a mean itch reduction of 82% at day 1 and 94% at day 7. Notably, no severe side effects were observed. Epidural lidocaine block proved to be an effective and safe long-term treatment option for individuals with refractory severe plaque psoriasis.


Assuntos
Anestésicos Locais , Lidocaína , Psoríase , Índice de Gravidade de Doença , Humanos , Lidocaína/administração & dosagem , Lidocaína/efeitos adversos , Projetos Piloto , Psoríase/tratamento farmacológico , Psoríase/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Anestésicos Locais/administração & dosagem , Anestésicos Locais/efeitos adversos , Prurido/etiologia , Prurido/tratamento farmacológico , Idoso , Resultado do Tratamento , Bloqueio Nervoso/métodos
16.
ACS Omega ; 9(11): 13298-13305, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38524490

RESUMO

Using high-dielectric inorganic ceramics as fillers can effectively increase the dielectric constant of polymer-based composites. However, a high percentage of fillers will inevitably lead to a decrease in the mechanical toughness of the composite materials. By introducing high aspect ratio copper calcium titanate (CaCu3Ti4O12) nanowires (CCTO NWs) and graphene as fillers, the ternary poly(vinylidene fluoride) (PVDF)-based composites (CCTO NWs-graphene)/PVDF with a significant one-dimensional orientation structure were prepared by hot stretching. CCTO NWs and graphene are arranged in a directional manner to form a large number of microcapacitor structures, which significantly improves the dielectric constant of the composites. When the ratio of CCTO NWs and graphene is 0.2 and 0.02, the oriented composites have the highest dielectric constant, which is 19.3% higher than the random composites, respectively. Numerical simulations reveal that the introduction of graphene and the construction of the one-dimensional oriented microstructure have a positive effect on improving the dielectric properties of the composites. This study provides a strategy to improve the dielectric properties of composite materials by structural design without changing the filler content, which has broad application prospects in the field of electronic devices.

17.
Exp Ther Med ; 27(4): 125, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38414786

RESUMO

Paeoniflorin (PF) is the primary component derived from Paeonia lactiflora and white peony root and has been used widely for the treatment of ulcerative colitis (UC) in China. UC primarily manifests as a chronic inflammatory response in the intestine. In the present study, a network pharmacology approach was used to explore the specific effects and underlying mechanisms of action of PF in the treatment of UC. A research strategy based on network pharmacology, combining target prediction, network construction, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, and molecular docking simulation was used to predict the targets of PF. A total of 288 potential targets of PF and 599 UC-related targets were identified. A total of 60 therapeutic targets of PF against UC were identified. Of these, 20 core targets were obtained by protein-protein interaction network construction. GO and KEGG pathway analyses showed that PF alleviated UC through EGFR tyrosine kinase inhibitor resistance, the IL-17 signaling pathway, and the PI3K/AKT signaling pathway. Molecular docking simulation showed that AKT1 and EGFR had good binding energy with PF. Animal-based experiments revealed that the administration of PF ameliorated the colonic pathological damage in a dextran sulfate sodium-induced mouse model, resulting in lower levels of proinflammatory cytokines including IL-1ß, IL-6, and TNF-α, and higher levels of IL-10 and TGF-ß. PF decreased the mRNA and protein expression levels of AKT1, EGFR, mTOR, and PI3K. These findings suggested that PF plays a therapeutic protective role in the treatment of UC by regulating the PI3K/AKT signaling pathway.

18.
Cell Physiol Biochem ; 31(4-5): 579-91, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23635649

RESUMO

BACKGROUND: Survival of random-pattern skin flaps is important for the success of plastic and reconstructive surgeries. This study investigates isoflurane-induced protection against ischemia of skin flap and the underlying molecular mechanism in this process. METHODS: Human umbilical vein endothelial cells (HUVECs) and human skin fibroblast cells were exposed to isoflurane for 4 h. Expression of hypoxia inducible factor-1α (HIF-1α), heme oxygenase-1 (HO-1) and vascular endothelial growth factor (VEGF) were analyzed up to 24 h post isoflurane exposure using qRT-PCR and western blot, or ELISA analyses. PI3K inhibitors--LY 294002 and wortmannin, mTOR inhibitor--rapamycin, and GSK3ß inhibitor--SB 216763 were used respectively to assess the effects of isoflurane treatment and HIF-1α expression. Furthermore, 40 rats were randomly divided into 5 groups (control, isoflurane, scrambled siRNA plus isoflurane, HIF-1α siRNA plus isoflurane, and DMOG) and subjected to random-pattern skin flaps operation. Rats were prepared for evaluation of flap survival and full-feld laser perfusion imager (FLPI) (at 7 day) and microvessel density evaluation (at 10 day). RESULTS: Isoflurane exposure induced expression of HIF-1α protein, HO-1 and VEGF mRNA and proteins in a time-dependent manner. Both LY 294002 and wortmannin inhibited phospho-Akt, phospho-mTOR, phospho-GSK 3ß and HIF-1α expression after isoflurane exposure. Both wortmannin and rapamycin inhibited isoflurane-induced phospho-4E-BP1 (Ser 65) and phospho-P70(s6k) (Thr 389) and HIF-1α expression. SB 216763 pre-treatment could further enhance isoflurane-induced expression of phospho-GSK 3ß (Ser 9) and HIF-1α protein compared to the isoflurane-alone cells. In animal experiments, isoflurane alone, scrambled siRNA plus isoflurane, or DMOG groups had significantly upregulated vascularity and increased survival of the skin flaps compared to the controls. However, HIF-1α knockdown abrogated the protective effect of isoflurane preconditioning in rats. CONCLUSIONS: Isoflurane preconditioning improves survival of skin flaps by up the regulation of HIF-1α expression via Akt-mTOR and Akt-GSK 3ß signaling pathways.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Precondicionamento Isquêmico , Isoflurano/farmacologia , Sobrevivência de Tecidos/efeitos dos fármacos , Animais , Linhagem Celular , Regulação da Expressão Gênica/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Masculino , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação , Estabilidade Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Pele/patologia , Retalhos Cirúrgicos/patologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Bioorg Med Chem ; 21(17): 5081-97, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23871442

RESUMO

DGAT-1 is an enzyme that catalyzes the final step in triglyceride synthesis. mRNA knockout experiments in rodent models suggest that inhibitors of this enzyme could be of value in the treatment of obesity and type II diabetes. The carboxylic acid-based DGAT-1 inhibitor 1 was advanced to clinical trials for the treatment of type 2 diabetes, despite of the low passive permeability of 1. Because of questions relating to the potential attenuation of distribution and efficacy of a poorly permeable agent, efforts were initiated to identify compounds with improved permeability. Replacement of the acid moiety in 1 with an oxadiazole led to the discovery of 52, which possesses substantially improved passive permeability. The resulting pharmacodynamic profile of this neutral DGAT-1 inhibitor was found to be similar to 1 at comparable plasma exposures.


Assuntos
Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Inibidores Enzimáticos/química , Oxazepinas/química , Administração Oral , Animais , Diacilglicerol O-Aciltransferase/metabolismo , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/uso terapêutico , Meia-Vida , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/tratamento farmacológico , Oxidiazóis/química , Oxazepinas/farmacocinética , Oxazepinas/uso terapêutico , Ligação Proteica , Ratos , Relação Estrutura-Atividade
20.
Exp Lung Res ; 39(7): 295-303, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23919323

RESUMO

Isoflurane (ISO) has been shown to attenuate acute lung injury (ALI). Induction of heme oxygenase-1 (HO-1) and suppression of inducible nitric oxide synthase (iNOS) expression provide cytoprotection in lung and vascular injury. The aim of this study was to investigate the effect of post-treatment with isoflurane on lung vascular permeability and the role of HO-1 in an ALI rat model induced by cecal ligation and puncture (CLP). Male Sprague-Dawley rats were randomly assigned to one of four groups: sham group, sham rats post-treated with vehicle (Sham); CLP group, CLP rats post-treated with vehicle (CLP); ISO group, CLP rats post-treated with isoflurane (ISO); and ZnPP group, CLP rats injected with zinc protoporphyrin IX (ZnPP), a competitive inhibitor of HO-1, 1 hour before the operation, and post-treated with isoflurane (ZnPP). Isoflurane (1.4%) was administered 2 hour after CLP. At 24 hour after CLP, the extent of ALI was evaluated by lung wet/dry ratio, Evans blue dye (EBD) extravasation, lung permeability index (LPI), as well as histological and immunohistochemical examinations. We also determined pulmonary iNOS and HO-1 expression. Compared with the CLP group, the isoflurane post-treatment group showed improved pulmonary microvascular permeability as detected by EBD extravasation, LPI, as well as histological and immunohistochemical examinations. Furthermore, isoflurane decreased iNOS and increased HO-1 expression in lung tissue. Pretreatment with ZnPP prevented the protective effects of isoflurane in rats. These findings indicate that the protective role of isoflurane post-conditioning against CLP-induced lung injury may be associated with its role in upregulating HO-1 in ALI.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Permeabilidade Capilar/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Isoflurano/farmacologia , Pulmão/irrigação sanguínea , Regulação para Cima/efeitos dos fármacos , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/etiologia , Animais , Modelos Animais de Doenças , Heme Oxigenase-1/antagonistas & inibidores , Heme Oxigenase-1/efeitos dos fármacos , Isoflurano/uso terapêutico , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Óxido Nítrico Sintase Tipo II/metabolismo , Protoporfirinas/farmacologia , Ratos , Ratos Sprague-Dawley , Sepse/complicações
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