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1.
J Sci Food Agric ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38501369

RESUMO

BACKGROUND: Fried foods are favored for their unique crispiness, golden color and flavor, but they also face great challenge because of their high oil content, high calories and the existence of compounds such as acrylamide and polycyclic aromatic hydrocarbons. Long-term consumption of fried foods may adversely affect health. Therefore, it is necessary to explore fried foods with lower oil contents and a high quality to meet the demand. RESULTS: A method of enzyme treatment was explored to investigate the effects of maltogenic amylase (MA), transglutaminase (TG) and bromelain (BRO) on the physicochemical properties of the batter and the quality of fried spring roll wrapper (FSRW). The results showed that the MA-, TG- or BRO-treated batters had a significant shear-thinning behavior, especially with an increase in viscosity upon increasing TG contents. FSRW enhanced its fracturability from 419.19 g (Control) to 616.50 g (MA-6 U g-1), 623.49 g (TG-0.75 U g-1) and 644.96 g (BRO-10 U g-1). Meanwhile, in comparison with BRO and MA, TG-0.5 U g-1 endowed batter with the highest density and thermal stability. MA-15 U g-1 and TG-0.5 U g-1 displayed FSRW with uniform and dense pores, and significantly reduced its oil content by 18.05% and 25.02%, respectively. Moreover, compared to MA and TG, BRO-50 U g-1 improved the flavor of FSRW. CONCLUSION: MA, TG or BRO played a key role in affecting the physicochemical properties of the batter and the quality of FSRW. TG-0.5 U g-1 remarkly reduced the oil content of FSRW with a great potential in practical application. © 2024 Society of Chemical Industry.

2.
Biomacromolecules ; 24(8): 3846-3857, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37475132

RESUMO

Melanoma is resistant to conventional chemotherapy and radiotherapy. Therefore, it is essential to develop a targeted, low-toxic, and minimally invasive treatment. Here, DTIC/ICG-Fe3O4@TpBD BSP/HA microneedles (MNs) were designed and fabricated, which can enhance targeting to melanoma and perform photothermal therapy (PTT) and chemotherapy simultaneously to synergistically exert anticancer effects. The system consisted of magnetic nanoparticles (DTIC/ICG-Fe3O4@TpBD), dissoluble matrix (Bletilla polysaccharide (BSP)/hyaluronic acid (HA)), and a polyvinyl alcohol backing layer. Due to the good magnetic responsiveness of Fe3O4@TpBD, dacarbazine (DTIC) and indocyanine green (ICG) can be better targeted to the tumor tissue and improve the therapeutic effect. BSP and HA have good biocompatibility and transdermal ability, so that the MNs can completely penetrate the tumor tissue, be dissolved by the interstitial fluid, and release DTIC and ICG. Under near-infrared (NIR) light irradiation, ICG converts light energy into thermal energy and induces ablation of B16-OVA melanoma cells. In vivo results showed that DTIC/ICG-Fe3O4@TpBD BSP/HA MNs combined with chemotherapy and PTT could effectively inhibit the growth of melanoma without tumor recurrence or significant weight loss in mice. Therefore, DTIC/ICG-Fe3O4@TpBD BSP/HA MNs are expected to provide new ideas and therapeutic approaches for the clinical treatment of melanoma.


Assuntos
Hipertermia Induzida , Melanoma , Estruturas Metalorgânicas , Nanopartículas , Animais , Camundongos , Hipertermia Induzida/métodos , Melanoma/tratamento farmacológico , Fototerapia/métodos , Verde de Indocianina/farmacologia , Dacarbazina , Linhagem Celular Tumoral
3.
Catheter Cardiovasc Interv ; 99(1): 98-113, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33909311

RESUMO

OBJECTIVES: To determine the association of extended-term (>12-month) versus short-term dual antiplatelet therapy (DAPT) with ischemic and hemorrhagic events in high-risk "TWILIGHT-like" patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) in clinical practice. BACKGROUND: Recent emphasis on shorter DAPT regimen after PCI irrespective of indication for PCI may fail to account for the substantial residual risk of recurrent atherothrombotic events in ACS patients. METHODS: All consecutive patients fulfilling the "TWILIGHT-like" criteria undergoing PCI were identified from the prospective Fuwai PCI Registry. High-risk patients (n = 8,358) were defined by at least one clinical and one angiographic feature based on TWILIGHT trial selection criteria. The primary ischemic endpoint was major adverse cardiac and cerebrovascular events at 30 months, composed of all-cause mortality, myocardial infarction, or stroke while BARC type 2, 3, or 5 bleeding was key secondary outcome. RESULTS: Of 4,875 high-risk ACS patients who remained event-free at 12 months after PCI, DAPT>12-month compared with shorter DAPT reduced the primary ischemic endpoint by 63% (1.5 vs. 3.8%; HRadj: 0.374, 95% CI: 0.256-0.548; HRmatched: 0.361, 95% CI: 0.221-0.590). The HR for cardiovascular death was 0.049 (0.007-0.362) and that for MI 0.45 (0.153-1.320) and definite/probable stent thrombosis 0.296 (0.080-1.095) in propensity-matched analyses. Rates of BARC type 2, 3, or 5 bleeding (0.9 vs. 1.3%; HRadj: 0.668 [0.379-1.178]; HRmatched: 0.721 [0.369-1.410]) did not differ significantly between two groups. CONCLUSIONS: Among high-risk ACS patients undergoing PCI, long-term DAPT, compared with shorter DAPT, reduced ischemic events without a concomitant increase in clinically meaning bleeding events, suggesting that prolonged DAPT can be considered in ACS patients who present with a particularly higher risk for thrombotic complications without excessive risk of bleeding.


Assuntos
Síndrome Coronariana Aguda , Intervenção Coronária Percutânea , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/terapia , Quimioterapia Combinada , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Estudos Prospectivos , Resultado do Tratamento
4.
J Interv Cardiol ; 2022: 3895205, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35095347

RESUMO

BACKGROUND: There is a paucity of real-world data regarding the clinical impact of dual antiplatelet therapy (DAPT) interruption (temporary or permanent) among patients at high ischemic risk. The aim of this study was to assess the risk of cardiovascular events after interruption of DAPT in high-risk PCI population. METHODS: This study used data from the Fuwai PCI registry, a large, prospective cohort of consecutive patients who underwent PCI. We assessed 3,931 patients with at least 1 high ischemic risk criteria of stent-related recurrent ischemic events proposed in the 2017 ESC guidelines for focused update on DAPT who were free of major cardiac events in the first 12 months. The primary ischemic endpoint was 30-month major adverse cardiac and cerebrovascular events, and the key safety endpoints were BARC class 2, 3, or 5 bleeding and net adverse clinical events. RESULTS: DAPT interruption within 12 months occurred in 1,122 patients (28.5%), most of which were due to bleeding events or patients' noncompliance to treatment. A multivariate Cox regression model, propensity score (PS) matching, and inverse probability of treatment weighting (IPTW) based on the propensity score demonstrated that DAPT interruption significantly increased the risk of primary ischemic endpoint compared with prolonged DAPT (3.9% vs. 2.2%; Cox-adjusted hazard ratio (HR): 1.840; 95% confidence interval (CI): 1.247 to 2.716; PS matching-HR: 2.049 [1.236-3.399]; IPTW-adjusted HR: 1.843 [1.250-2.717]). This difference was driven mainly by all-cause death (1.8% vs. 0.7%) and MI (1.3% vs. 0.5%). Furthermore, the rate of net adverse clinical events (4.9% vs. 3.2%; Cox-adjusted HR: 1.581 [1.128-2.216]; PS matching-HR: 1.639 [1.075-2.499]; IPTW-adjusted HR: 1.554 [1.110-2.177]) was also higher in patients with DAPT interruption (≤12 months), whereas no significant differences between groups were observed in terms of BARC 2, 3, or 5 bleeding. These findings were consistent across various stent-driven high-ischemic risk subsets with respect to the primary ischemic endpoints, with a greater magnitude of harm among patients with diffuse multivessel diabetic coronary artery disease. CONCLUSIONS: In patients undergoing high-risk PCI, interruption of DAPT in the first 12 months occurred infrequently and was associated with a significantly higher adjusted risk of major adverse cardiovascular events and net adverse clinical events. 2017 ESC stent-driven high ischemic risk criteria may help clinicians to discriminate patient selection in the use of long-term DAPT when the ischemic risk certainly overcomes the bleeding one.


Assuntos
Stents Farmacológicos , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Estudos Prospectivos , Stents/efeitos adversos
5.
Acta Pharmacol Sin ; 43(11): 2807-2816, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35581293

RESUMO

Our previous study showed that H3 receptor antagonists reduced neuronal apoptosis and cerebral infarction in the acute stage after cerebral ischemia, but through an action independent of activation of histaminergic neurons. Because enhanced angiogenesis facilitates neurogenesis and neurological recovery after ischemic stroke, we herein investigated whether antagonism of H3R promoted angiogenesis after brain ischemia. Photothrombotic stroke was induced in mice. We showed that administration of H3R antagonist thioperamide (THIO, 10 mg·kg-1·d-1, i.p., from D1 after cerebral ischemia) significantly improved angiogenesis assessed on D14, and attenuated neurological defects on D28 after cerebral ischemia. Compared with wild-type mice, Hrh3-/- mice displayed more blood vessels in the ischemic boundary zone on D14, and THIO administration did not promote angiogenesis in these knockout mice. THIO-promoted angiogenesis in mice was reversed by i.c.v. injection of H3R agonist immepip, but not by H1 and H2 receptor antagonists, histidine decarboxylase inhibitor α-fluoromethylhistidine, or histidine decarboxylase gene knockout (HDC-/-), suggesting that THIO-promoted angiogenesis was independent of activation of histaminergic neurons. In vascular endothelial cells (bEnd.3), THIO (10-9-10-7 M) dose-dependently facilitated cell migration and tube formation after oxygen glucose deprivation (OGD), and H3R knockdown caused similar effects. We further revealed that H3R antagonism reduced the interaction between H3R and Annexin A2, while knockdown of Annexin A2 abrogated THIO-promoted angiogenesis in bEnd.3 cells after OGD. Annexin A2-overexpressing mice displayed more blood vessels in the ischemic boundary zone, which was reversed by i.c.v. injection of immepip. In conclusion, this study demonstrates that H3R antagonism promotes angiogenesis after cerebral ischemia, which is independent of activation of histaminergic neurons, but related to the H3R on vascular endothelial cells and its interaction with Annexin A2. Thus, H3R antagonists might be promising drug candidates to improve angiogenesis and neurological recovery after ischemic stroke.


Assuntos
Anexina A2 , Isquemia Encefálica , AVC Isquêmico , Receptores Histamínicos H3 , Animais , Camundongos , Histidina Descarboxilase/genética , Histidina Descarboxilase/metabolismo , Receptores Histamínicos H3/metabolismo , Histamina , Células Endoteliais/metabolismo , Isquemia Encefálica/tratamento farmacológico , Camundongos Knockout , Infarto Cerebral
6.
Int J Mol Sci ; 23(10)2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35628302

RESUMO

Fibroblast growth factor 21 (FGF21) functions as a polypeptide hormone to regulate glucose and lipid metabolism, and its expression is regulated by cellular metabolic stress. Pyruvate is an important intermediate metabolite that acts as a key hub for cellular fuel metabolism. However, the effect of pyruvate on hepatic FGF21 expression and secretion remains unknown. Herein, we examined the gene expression and protein levels of FGF21 in human hepatoma HepG2 cells and mouse AML12 hepatocytes in vitro, as well as in mice in vivo. In HepG2 and AML12 cells, pyruvate at concentrations above 0.1 mM significantly increased FGF21 expression and secretion. The increase in cellular cAMP levels by adenylyl cyclase activation, phosphodiesterase (PDE) inhibition and 8-Bromo-cAMP administration significantly restrained pyruvate-stimulated FGF21 expression. Pyruvate significantly increased PDE activities, reduced cAMP levels and decreased CREB phosphorylation. The inhibition of exchange protein directed activated by cAMP (Epac) and cAMP response element binding protein (CREB) upregulated FGF21 expression, upon which pyruvate no longer increased FGF21 expression. The increase in plasma pyruvate levels in mice induced by the intraperitoneal injection of pyruvate significantly increased FGF21 gene expression and PDE activity with a reduction in cAMP levels and CREB phosphorylation in the mouse liver compared with the control. In conclusion, pyruvate activates PDEs to reduce cAMP and then inhibits the cAMP-Epac-CREB signaling pathway to upregulate FGF21 expression in hepatocytes.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Fatores de Crescimento de Fibroblastos , Fatores de Troca do Nucleotídeo Guanina , Fígado , Diester Fosfórico Hidrolases , Ácido Pirúvico , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/antagonistas & inibidores , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Fatores de Crescimento de Fibroblastos/biossíntese , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/metabolismo , Expressão Gênica , Fatores de Troca do Nucleotídeo Guanina/antagonistas & inibidores , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Células Hep G2 , Humanos , Fígado/enzimologia , Fígado/metabolismo , Camundongos , Diester Fosfórico Hidrolases/metabolismo , Ácido Pirúvico/sangue , Ácido Pirúvico/metabolismo , Ácido Pirúvico/farmacocinética , Transdução de Sinais/fisiologia
7.
Acta Pharmacol Sin ; 42(8): 1288-1297, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33159174

RESUMO

Recent evidence shows that the expression levels of histamine receptor H3 (Hrh3) are upregulated in several types of cancer. However, the role of Hrh3 in non-small cell lung cancer (NSCLC) has not been elucidated. In the present study, we showed that the expression levels of Hrh3 were significantly increased in NSCLC samples, and high levels of Hrh3 were associated with poor overall survival (OS) in NSCLC patients. In five human NSCLC cell lines tested, Hrh3 was significantly upregulated. In NSCLC cell lines H1975, H460, and A549, Hrh3 antagonist ciproxifan (CPX, 10-80 µM) exerted moderate and concentration-dependent inhibition on the cell growth and induced apoptosis, whereas its agonist RAMH (80 µM) reversed these effects. Furthermore, inhibition of Hrh3 by CPX or siRNA retarded the migration and invasion of NSCLC cells through inhibiting epithelial-mesenchymal transition (EMT) progression via reducing the phosphorylation of PI3K/Akt/mTOR and MEK/ERK signaling pathways. In nude mice bearing H1975 cell xenograft or A549 cell xenograft, administration of CPX (3 mg/kg every other day, intraperitoneal) significantly inhibited the tumor growth with increased E-cadherin and ZO-1 expression and decreased Fibronectin expression in tumor tissue. In conclusion, this study reveals that Hrh3 plays an important role in the growth and metastasis of NSCLC; it might be a potential therapeutic target against the lung cancer.


Assuntos
Antineoplásicos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Antagonistas dos Receptores Histamínicos/farmacologia , Imidazóis/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Receptores Histamínicos H3/metabolismo , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Antagonistas dos Receptores Histamínicos/uso terapêutico , Humanos , Imidazóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Sci Food Agric ; 101(12): 4959-4968, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33543501

RESUMO

BACKGROUND: Protein can be used as an emulsifier to improve emulsion stability at the interface of water-in-oil emulsion. However, natural soybean protein isolate (SPI) does not meet the high demands as an emulsifier in the food industry. The effect of acylation modification by ethylenediaminetetraacetic dianhydride (EDTAD; 0-300 g kg-1 ) on the physicochemical properties of SPI was studied. RESULTS: The results of the Fourier transform infrared spectra analyses showed that carboxyl groups were introduced into the SPI structure by the EDTAD treatment. The carboxyl concentration of SPI was increased by 30-74.07% with an increase in EDTAD addition from 50 to 300 g kg-1 . When 150 g kg-1 EDTAD was added, the surface hydrophobicity, the emulsifying activity, and the absolute value of the zeta potential were increased by 213%, 120%, and 68% respectively, and the particle size decreased to 247 nm. The droplet size of emulsion decreased to 10 µm when pH was 6. At the same concentration of SPI and pH, the absolute value of zeta potential of the emulsion was biggest. A comparison of the emulsions during storage showed the improvement of emulsion stability was related to the increase in the zeta potential and the decrease in the average particle size. The experimental group showed no destabilization on day 21, and no obvious aggregation phenomenon was observed. CONCLUSION: Acylation modification by EDTAD changed the emulsifying properties of SPI and enhanced the stability of the SPI emulsion. © 2021 Society of Chemical Industry.


Assuntos
Glycine max/química , Proteínas de Soja/química , Acilação , Emulsões/química , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Estabilidade Proteica
9.
Proteins ; 88(9): 1226-1232, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32337767

RESUMO

Cyanophages, widespread in aquatic systems, are a class of viruses that specifically infect cyanobacteria. Though they play important roles in modulating the homeostasis of cyanobacterial populations, little is known about the freshwater cyanophages, especially those hypothetical proteins of unknown function. Mic1 is a freshwater siphocyanophage isolated from the Lake Chaohu. It encodes three hypothetical proteins Gp65, Gp66, and Gp72, which share an identity of 61.6% to 83%. However, we find these three homologous proteins differ from each other in oligomeric state. Moreover, we solve the crystal structure of Gp72 at 2.3 Å, which represents a novel fold in the α + ß class. Structural analyses combined with redox assays enable us to propose a model of disulfide bond mediated oligomerization for Gp72. Altogether, these findings provide structural and biochemical basis for further investigations on the freshwater cyanophage Mic1.


Assuntos
Bacteriófagos/química , Cianobactérias/virologia , Dissulfetos/química , Proteínas Virais/química , Sequência de Aminoácidos , Bacteriófagos/genética , Bacteriófagos/metabolismo , Sítios de Ligação , Clonagem Molecular , Cristalografia por Raios X , Dissulfetos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Água Doce/microbiologia , Água Doce/virologia , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Modelos Moleculares , Oxirredução , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Dobramento de Proteína , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Proteínas Virais/genética , Proteínas Virais/metabolismo
10.
Cell Biol Int ; 44(1): 89-97, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31322778

RESUMO

Free fatty acid receptor G protein-coupled receptor 120 (GPR120) is highly expressed in macrophages and was reported to inhibit lipopolysaccharide (LPS)-stimulated cytokine expression. Under inflammation, macrophages exhibit striking functional changes, but changes in GPR120 expression and signaling are not known. In this study, the effects of LPS treatment on macrophage GPR120 expression and activation were investigated. The results showed that LPS inhibited GPR120 expression in mouse macrophage cell line Ana-1 cells. Moreover, LPS treatment inhibited GPR120 expression in mouse alveolar macrophages both in vitro and in vivo. The inhibitory effect of LPS on GPR120 expression was blocked by Toll-like receptor 4 (TLR4) inhibitor TAK242 and p38 mitogen-activated protein kinase inhibitor LY222820, but not by ERK1/2 inhibitor U0126 and c-Jun N-terminal kinase inhibitor SP600125. LPS-induced inhibition of GPR120 expression was not attenuated by GPR120 agonists TUG891 and GW9508. TUG891 inhibited the phagocytosis of alveolar macrophages, and LPS treatment counteracted the effects of TUG891 on phagocytosis. These results indicate that pretreatment with LPS inhibits GPR120 expression and activation in macrophages. It is suggested that LPS-induced inhibition of GPR120 expression is a reaction enhancing the LPS-induced pro-inflammatory response of macrophages.

11.
Acta Pharmacol Sin ; 41(6): 825-834, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32066885

RESUMO

Chalcomoracin (CMR) is a kind of Diels-Alder adduct extracted from the mulberry leaves. Recent studies showed that CMR has a broad spectrum of anticancer activities and induces paraptosis in breast cancer and prostate cancer cells. In this study, we investigated the effects of CMR against human non-small cell lung cancer cells and the underlying mechanisms. We found that CMR dose-dependently inhibited the proliferation of human lung cancer H460, A549 and PC-9 cells. Furthermore, exposure to low and median doses of CMR induced paraptosis but not apoptosis, which was presented as the formation of extensive cytoplasmic vacuolation with increased expression of endoplasmic reticulum stress markers, Bip and Chop, as well as activation of MAPK pathway in the lung cancer cells. Knockdown of Bip with siRNA not only reduced the cell-killing effect of CMR, but also decreased the percentage of cytoplasmic vacuoles in H460 cells. Moreover, CMR also increased the sensitivity of lung cancer cells to radiotherapy through enhanced endoplasmic reticulum stress. In lung cancer H460 cell xenograft nude mice, combined treatment of CMR and radiation caused greatly enhanced tumor growth inhibition with upregulation of endoplasmic reticulum stress proteins and activation of pErk in xenograft tumor tissue. These data demonstrate that the anticancer activity and radiosensitization effect of CMR result from inducing paraptosis, suggesting that CMR could be considered as a potential anticancer agent and radiation sensitizer in the future cancer therapeutics.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Benzofuranos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/terapia , Células A549 , Animais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Células Tumorais Cultivadas
12.
Sheng Li Xue Bao ; 72(2): 175-180, 2020 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-32328611

RESUMO

The present study was aimed to clarify the signaling molecular mechanism by which fibroblast growth factor 21 (FGF21) regulates leptin gene expression in adipocytes. Differentiated 3T3-F442A adipocytes were used as study object. The mRNA expression level of leptin was detected by fluorescence quantitative RT-PCR. The phosphorylation levels of proteins of signal transduction pathways were detected by Western blot. The results showed that FGF21 significantly down-regulated the mRNA expression level of leptin in adipocytes, and FGF21 receptor inhibitor BGJ-398 could completely block this effect. FGF21 up-regulated the phosphorylation levels of ERK1/2 and AMPK in adipocytes. Either ERK1/2 inhibitor SCH772984 or AMPK inhibitor Compound C could partially block the inhibitory effect of FGF21, and the combined application of these two inhibitors completely blocked the effect of FGF21. Neither PI3K inhibitor LY294002 nor Akt inhibitor AZD5363 affected the inhibitory effect of FGF21 on leptin gene expression. These results suggest that FGF21 may inhibit leptin gene expression by activating ERK1/2 and AMPK signaling pathways in adipocytes.


Assuntos
Adipócitos/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Leptina/metabolismo , Células 3T3 , Adenilato Quinase , Animais , Regulação para Baixo , Sistema de Sinalização das MAP Quinases , Camundongos , Fosforilação , Transdução de Sinais
13.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(7): 790-795, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32669180

RESUMO

This article reported the clinical characteristics and SRD5A2 gene mutation pattern of a child with steroid 5-α reductase type 2 deficiency. The 2-month-old boy showed hypospadias and short penis shortly after birth. DNA was extracted from the peripheral blood of the child and his parents. The endocrine disease-related genes were captured and sequenced by high-throughput sequencing technology, and the family DNA samples were verified by Sanger sequencing. The results showed that c.680G>A(p.R227Q) and c.608G>A(p.G203D) compound heterozygous mutations existed in the SRD5A2 gene of the child. The c.680G>A mutation inherited from his father, which was a known pathogenic mutation. The c.608G>A mutation originated from his mother, which was a novel mutation discovered in this study. These results provide molecular evidence for the etiological diagnosis of the child and genetic counseling for the family, as well as extend the mutation spectrum of SRD5A2 gene.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Proteínas de Membrana/genética , Sequência de Bases , Criança , Feminino , Humanos , Hipospadia , Lactente , Masculino , Mutação
14.
Biochem Biophys Res Commun ; 515(3): 510-515, 2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31171360

RESUMO

Carboxysome, encapsulating an enzymatic core within an icosahedral-shaped semipermeable protein shell, could enhance CO2 fixation under low CO2 conditions in the environment. The shell of Halothiobacillus neapolitanus α-carboxysome possesses two 38% sequence-identical pentameric proteins, namely CsoS4A and CsoS4B. However, the functions of two paralogous pentameric proteins in α-carboxysome assembly remain unknown. Here we report the crystal structure of CsoS4B at 2.15 Šresolution. It displays as a stable pentamer, each subunit of which consists of a ß-barrel core domain, in addition to an insertion of helix α1 that forms the central pore. Structural comparisons and multiple-sequence alignment strongly indicate that CsoS4A and CsoS4B differ from each other in interacting with various components of α-carboxysome, despite they share a similar overall structure. These findings provide the structural basis for further investigations on the self-assembly process of carboxysome.


Assuntos
Proteínas de Bactérias/química , Halothiobacillus/química , Multimerização Proteica , Sequência de Aminoácidos , Cristalografia por Raios X , Modelos Moleculares , Eletricidade Estática , Homologia Estrutural de Proteína
15.
New Phytol ; 222(1): 588-603, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30484867

RESUMO

During male gametogenesis in Arabidopsis, the haploid microspore undergoes an asymmetric division to produce a vegetative and a generative cell, the latter of which continues to divide symmetrically to form two sperms. This simple system couples cell cycle with cell fate specification. Here we addressed the role of DNA replication in male gametogenesis using a mutant bicellular pollen 1 (bice1), which produces bicellular, rather than tricellular, pollen grains as in the wild-type plant at anthesis. The mutation prolonged DNA synthesis of the generative cell, which resulted in c. 40% of pollen grains arrested at the two-nucleate stage. The extended S phase did not impact the cell fate of the generative cell as shown by cell-specific markers. BICE1 encodes a plant homolog of human D123 protein that is required for G1 progression, but the underlying mechanism is unknown. Here we showed that BICE1 interacts with MCM4 and MCM7 of the pre-replication complex. Consistently, double mutations in BICE1 and MCM4, or MCM7, also led to bicellular pollen and condensed chromosomes. These suggest that BICE1 plays a role in modulating DNA replication via interaction with MCM4 and MCM7.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Ciclo Celular/metabolismo , Replicação do DNA , Pólen/crescimento & desenvolvimento , Pólen/metabolismo , Arabidopsis/embriologia , Arabidopsis/genética , Ciclo Celular/genética , Núcleo Celular/metabolismo , DNA de Plantas/biossíntese , Regulação da Expressão Gênica de Plantas , Mutação/genética , Fenótipo , Pólen/citologia , Pólen/ultraestrutura , Ligação Proteica , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
16.
Sheng Li Xue Bao ; 71(2): 350-360, 2019 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-31008496

RESUMO

Facilitative glucose transporters (GLUT) are proteins that mediate glucose transmembrane transport in the form of facilitated diffusion, which play an important role in regulating cell energy metabolism. There are many breakthroughs in researches of facilitative GLUT in recent years. It has been known that there are 14 subtypes of facilitative GLUT with obvious tissue specificity in distribution and physiological function. In the present review, the tissue and cellular distribution, subcellular localization, expression regulation, physiological function and the relationship to diseases of facilitative GLUT subtypes were summarized, in order to further understand their physiological and pathophysiological significances.


Assuntos
Doença , Metabolismo Energético , Proteínas Facilitadoras de Transporte de Glucose/fisiologia , Transporte Biológico , Glucose , Humanos
17.
J Am Chem Soc ; 140(31): 9912-9920, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-30008215

RESUMO

Efficient delivery and endo-lysosomal release of active proteins in living cells remain a challenge in protein-based theranostics. We report a novel protein delivery platform using protein-encapsulating biomineralized metal-organic framework (MOF) nanoparticles (NPs). This platform introduces an adapted biomimetic mineralization method for facile synthesis of MOF NPs with high protein encapsulation efficiency and a new polymer coating strategy to confer the NPs with long-term stability. In vitro results show that protein-encapsulating MOF NPs have the advantages of preserving protein activity for months and protecting proteins from enzyme-mediated degradation. Live cell studies reveal that MOF NPs enable rapid cellular uptake, efficient release and escape of proteins from endo-lysosomes, and preservation of protein activity in living cells. Moreover, the developed platform is demonstrated to enable easy encapsulation of multiple proteins in single MOF NPs for efficient protein co-delivery. To our knowledge, it is the first time that protein-encapsulating MOF NPs have been developed as a generally applicable strategy for intracellular delivery of native active proteins. The developed protein-encapsulating biomineralized MOF NPs can provide a valuable platform for protein-based theranostic applications.


Assuntos
Endossomos/metabolismo , Lisossomos/metabolismo , Estruturas Metalorgânicas , Minerais/química , Nanopartículas/química , Proteínas/metabolismo , Células HeLa , Humanos , Nanomedicina Teranóstica
19.
J Sci Food Agric ; 97(3): 868-874, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27197789

RESUMO

BACKGROUND: Crude camellia seed oil is rich in free fatty acids, which must be removed to produce an oil of acceptable quality. In the present study, we reduced the free fatty acid content of crude camellia seed oil by lipophilization of epicatechin with these free fatty acids in the presence of Candida antarctica lipase B (Novozym 435), and this may enhance the oxidative stability of the oil at the same time. RESULTS: The acid value of crude camellia seed oil reduced from 3.7 to 2.5 mgKOH g-1 after lipophilization. Gas chomatography-mass spectrometry analysis revealed that epicatechin oleate and epicatechin palmitate were synthesized in the lipophilized oil. The peroxide, p-anisidine, and total oxidation values during heating of the lipophilized oil were much lower than that of the crude oil and commercially available camellia seed oil, suggesting that lipophilized epicatechin derivatives could help enhance the oxidative stability of edible oil. CONCLUSION: The enzymatic process to lipophilize epicatechin with the free fatty acids in crude camellia seed oil described in the present study could decrease the acid value to meet the quality standards for commercial camellia seed oil and, at the same time, obtain a new edible camellia seed oil product with good oxidative stability. © 2016 Society of Chemical Industry.


Assuntos
Antioxidantes/metabolismo , Camellia sinensis/química , Catequina/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Proteínas Fúngicas/metabolismo , Lipase/metabolismo , Óleos de Plantas/química , Sementes/química , Antioxidantes/análise , Antioxidantes/química , Catequina/análogos & derivados , Catequina/análise , Catequina/química , China , Gorduras Insaturadas na Dieta/análise , Gorduras Insaturadas na Dieta/metabolismo , Enzimas Imobilizadas/metabolismo , Ácidos Graxos não Esterificados/análise , Ácidos Graxos não Esterificados/química , Manipulação de Alimentos , Qualidade dos Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta/efeitos adversos , Interações Hidrofóbicas e Hidrofílicas , Ácidos Oleicos/análise , Ácidos Oleicos/química , Ácidos Oleicos/metabolismo , Oxirredução , Palmitatos/análise , Palmitatos/química , Palmitatos/metabolismo , Solubilidade
20.
Mol Cell Biochem ; 420(1-2): 95-106, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27449933

RESUMO

Insufficient insulin produced by pancreatic ß-cells in the control of blood sugar is a central feature of the etiology of diabetes. Reports have shown that endoplasmic reticulum (ER) stress is fundamentally involved in ß-cell dysfunction. In this study, we hypothesized that NAD-dependent deacetylase sirtuin-3 (SIRT3), an important regulator of cell metabolism, protects pancreatic ß-cells from ER stress-mediated apoptosis. To validate our hypothesis, a rat diabetic model was established by a high-fat diet (HFD). We found that SIRT3 expression was markedly decreased in NIT1 and INS1 cells incubated with palmitate. Palmitate treatment significantly decreased ß-cell viability and insulin secretion, and promoted malondialdehyde (MDA) formation. However, SIRT3 overexpression in NIT1 and INS1 cells reversed these effects, resulting in higher insulin secretion, decreased ß-cell apoptosis, and downregulation of the expression of ER stress-associated genes. Moreover, SIRT3 overexpression also inhibited calcium influx and the hyperacetylation of glucose-regulated protein of 78 kDa (GRP78). SIRT3 knockdown effectively enhanced the upregulation of phospho-extracellular regulated protein kinases (pERK), inositol-requiring enzyme-1 (IRE1), activating transcription factor 6 (ATF6), and C/EBP homologous protein (CHOP) induced by palmitate, and promoted palmitate-induced ß-cell apoptosis and dysfunction. Taken together, our results suggest that SIRT3 is an integral regulator of ER function and that its depletion might result in the hyperacetylation of critical ER proteins that protect against islet lipotoxicity under conditions of nutrient excess.


Assuntos
Apoptose , Sinalização do Cálcio , Estresse do Retículo Endoplasmático , Regulação Enzimológica da Expressão Gênica , Células Secretoras de Insulina/enzimologia , Sirtuínas/biossíntese , Animais , Células Secretoras de Insulina/patologia , Masculino , Ratos , Ratos Sprague-Dawley
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