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1.
Cell ; 173(3): 762-775.e16, 2018 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-29677517

RESUMO

Mechanotransduction plays a crucial role in vascular biology. One example of this is the local regulation of vascular resistance via flow-mediated dilation (FMD). Impairment of this process is a hallmark of endothelial dysfunction and a precursor to a wide array of vascular diseases, such as hypertension and atherosclerosis. Yet the molecules responsible for sensing flow (shear stress) within endothelial cells remain largely unknown. We designed a 384-well screening system that applies shear stress on cultured cells. We identified a mechanosensitive cell line that exhibits shear stress-activated calcium transients, screened a focused RNAi library, and identified GPR68 as necessary and sufficient for shear stress responses. GPR68 is expressed in endothelial cells of small-diameter (resistance) arteries. Importantly, Gpr68-deficient mice display markedly impaired acute FMD and chronic flow-mediated outward remodeling in mesenteric arterioles. Therefore, GPR68 is an essential flow sensor in arteriolar endothelium and is a critical signaling component in cardiovascular pathophysiology.


Assuntos
Mecanotransdução Celular , Interferência de RNA , Receptores Acoplados a Proteínas G/fisiologia , Animais , Materiais Biocompatíveis , Cálcio/metabolismo , Linhagem Celular Tumoral , Células Endoteliais/fisiologia , Endotélio Vascular/citologia , Células HEK293 , Células Endoteliais da Veia Umbilical Humana , Humanos , Concentração de Íons de Hidrogênio , Artérias Mesentéricas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/metabolismo , RNA Interferente Pequeno/metabolismo , Receptores Acoplados a Proteínas G/genética , Resistência ao Cisalhamento , Estresse Mecânico , Resistência Vascular
2.
Org Biomol Chem ; 22(15): 3009-3018, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38529785

RESUMO

Catalytic activity is undoubtedly a key focus in enzyme engineering. The complicated reaction conditions hinder some enzymes from industrialization even though they have relatively promising activity. This has occurred to some dehydrogenases. Hydroxysteroid dehydrogenases (HSDHs) specifically catalyze the conversion between hydroxyl and keto groups, and hold immense potential in the synthesis of steroid medicines. We underscored the importance of 7α-HSDH activity, and analyzed the overall robustness and underlying mechanisms. Employing a high-throughput screening approach, we comprehensively assessed a mutation library, and obtained a mutant with enhanced enzymatic activity and overall stability/tolerance. The superior mutant (I201M) was identified to harbor improved thermal stability, substrate susceptibility, cofactor affinity, as well as the yield. This mutant displayed a 1.88-fold increase in enzymatic activity, a 1.37-fold improvement in substrate tolerance, and a 1.45-fold increase in thermal stability when compared with the wild type (WT) enzyme. The I201M mutant showed a 2.25-fold increase in the kcat/KM ratio (indicative of a stronger binding affinity for the cofactor). This mutant did not exhibit the highest enzyme activity compared with all the tested mutants, but these improved characteristics contributed synergistically to the highest yield. When a substrate at 100 mM was present, the 24 h yield by I201M reached 89.7%, significantly higher than the 61.2% yield elicited by the WT enzyme. This is the first report revealing enhancement of the catalytic efficiency, cofactor affinity, substrate tolerance, and thermal stability of NAD(H)-dependent 7α-HSDH through a single-point mutation. The mutated enzyme reached the highest enzymatic activity of 7α-HSDH ever reported. High enzymatic activity is undoubtedly crucial for enabling the industrialization of an enzyme. Our findings demonstrated that, when compared with other mutants boasting even higher enzymatic activity, mutants with excellent overall robustness were superior for industrial applications. This principle was exemplified by highly active enzymes such as 7α-HSDH.


Assuntos
Hidroxiesteroide Desidrogenases , Mutação Puntual , Hidroxiesteroide Desidrogenases/genética , Hidroxiesteroide Desidrogenases/metabolismo , Mutação , Catálise , Cinética
3.
J Biochem Mol Toxicol ; 37(12): e23487, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37718545

RESUMO

Resistance to chemotherapy in cancer leads to poor therapeutic outcomes and also leads to challenges in treatment. The present work evaluated the mechanism involved in the resistance of 5-flurouracil (5-FU) in pancreatic cancer. At least 14 different pancreatic cancer (PC) cell lines were used for the study. For in vivo study female nude mice were selected. Patient-derived tumor xenograft samples were obtained from patients. The study involved, study for glucose uptake, fluorescence-activated cell sorting for glucose transporter, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide for cell survival, Picto-micrography for clonogenic assay, glutamine uptake assay, extracellular acidification and oxygen consumption rate, carbon dioxide release assay and lactate assay were also done. In addition to this, quantitative real-time polymerase chain reaction analysis for expression of genes, chromatin immunoprecipitation assay, western blot for protein expression, and immunohistochemical analysis in tumor sections, the tumors were studied by imaging for hypoxia and localization of TKT and CTPS-2. Also, patient-derived xenograft tumors were engrafted in nude mice, followed by a glucose uptake assay. We reported that elevated glycolytic flux causes dependence on glucose in cancer cells and, at the same time, increases pyrimidine biosynthesis. It was also found that stem cell factor-mediated stabilization of hypoxia-inducible factor-1a (HIF-1α) modulates the resistance in PC. Targeting HIF-1α in combination with 5-FU, strongly reduced the tumor burden. The study concludes that stem cell factor modulates HIF-1α and decreases the sensitivity in 5-FU resistant pancreatic cancer cells by targeting glucose metabolism. Deceased expression levels of CTPS-2 and TKT, which are regulators of pyrimidine biosynthesis could better the chance of survival in patients of pancreatic cancer receiving treatment of 5-FU.


Assuntos
Neoplasias Pancreáticas , Fator de Células-Tronco , Animais , Camundongos , Humanos , Feminino , Camundongos Nus , Fator de Células-Tronco/uso terapêutico , Neoplasias Pancreáticas/metabolismo , Glucose/metabolismo , Hipóxia , Linhagem Celular Tumoral , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Pirimidinas , Subunidade alfa do Fator 1 Induzível por Hipóxia
4.
Molecules ; 28(3)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36771015

RESUMO

Polygonati Rhizoma, a typical homology of medicine and food, possesses remarkable anti-fatigue, anti-aging, metabolic regulatory, immunomodulatory, anti-inflammatory, neuroprotective, anti-diabetes, and anti-cancer effects. Among bioactive phytochemicals in Polygonati Rhizoma, polysaccharides play important roles in the health-promoting activities through the mechanisms mentioned above and potential synergistic effects with other bioactives. In this review, we briefly introduce the updated biosynthesis of polysaccharides, the purification method, the structure characterization, and food applications, and discuss in detail the biological activities of Polygonati Rhizoma polysaccharides and associated mechanisms, aiming at broadening the usage of Polygonati Rhizoma as functional food and medicine.


Assuntos
Medicamentos de Ervas Chinesas , Polygonatum , Polygonatum/química , Polissacarídeos/farmacologia , Polissacarídeos/análise , Medicamentos de Ervas Chinesas/química , Compostos Fitoquímicos/análise , Rizoma/química , Anti-Inflamatórios/análise
5.
Curr Issues Mol Biol ; 44(10): 4822-4837, 2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36286043

RESUMO

Atherosclerosis is a major risk factor for type 2 diabetes (T2D) mortality. We aim to investigate the changes in miR-21, miR-122, miR-33a and miR-3064-5p in circulation and the liver of ApoE-/- mice with streptozocin (STZ)-induced T2D. Twenty 5-week-old male ApoE-/- mice were randomly assigned to the control (n = 10) and T2D group (n = 10) and intraperitoneally injected with a citrate buffer and streptozotocin (STZ) (40 mg/kg BW) once a day for three consecutive days. The successfully STZ-induced T2D mice (n = 5) and control mice (n = 5) were then fed with a high-fat diet (HFD) for 34 weeks. Compared to the control mice, ApoE-/- mice with STZ-induced T2D had slower (p < 0.05) growth, increased (p < 0.05) total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C), decreased (p < 0.05) high-density lipoprotein cholesterol (HDL-C) in serum, reduced (p < 0.05) TC and sterol regulatory element-binding protein-2 (Srebp-2), elevated (p < 0.05) ATP-binding-cassette-transporter-A1 (Abca1) in the liver, aggravated (p < 0.05) atherosclerotic lesions in the aorta, downregulated (p < 0.05) miR-21 and miR-33a, and upregulated (p < 0.05) miR-122 and miR-3064-5p in serum and the liver. In addition, the aortic lesions showed a positive correlation with miR-122 (r = 1.000, p = 0.001) and a negative correlation with miR-21 (r = −1.000, p = 0.001) in ApoE-/- mice with T2D. In conclusion, T2D-accelerated atherosclerosis correlates with a reduction in miR-21 and miR-33a and an elevation in miR-122 and miR-3064-5p in circulation and the liver of ApoE-/- mice.

6.
Semin Dial ; 35(4): 366-371, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35460110

RESUMO

Hepatorenal syndrome (HRS) is one of the most severe complications in advanced cirrhosis. Type-1 HRS is relatively uncommon, yet carries considerably higher mortality rate. Effective treatment for HRS, especially therapy towards survival benefits, is still limited. However, the role for dialysis in HRS has been questioned over the years. The initiation of dialysis remains controversial for those who aren't transplant candidates. Meanwhile, there's a growing attention towards the successful use of peritoneal dialysis (PD) in cirrhotic patients. Herein, we report a case of HRS-1 in a 76-year-old male patient with decompensated cirrhosis. Through a series of adjustments of hemodialysis regimens and pharmacological prescriptions, patient stabilized and the opportunity for transjugular intrahepatic portosystemic shunt (TIPS) insertion was gained. PD was initiated after TIPS placement. With a gradual decrease of dialysis dose, patient successfully weaned off PD and achieved both reversal of HRS and kidney recovery. Markedly improved nutritional status and quality of life were reported. The potential role of dialysis and TIPS in HRS may be worth revisiting. Further studies regarding the optimal timing of dialysis initiation, choices of dialysis modality, and efficacy of dialysis therapy in combination with TIPS in HRS patients are warranted.


Assuntos
Síndrome Hepatorrenal , Transplante de Fígado , Derivação Portossistêmica Transjugular Intra-Hepática , Idoso , Síndrome Hepatorrenal/etiologia , Síndrome Hepatorrenal/terapia , Humanos , Rim , Cirrose Hepática/complicações , Transplante de Fígado/efeitos adversos , Masculino , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Qualidade de Vida , Diálise Renal/efeitos adversos
7.
Phys Chem Chem Phys ; 24(48): 29570-29578, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36448558

RESUMO

Polarized structured nitride semiconductors are attractive due to their unique and environment-friendly electronic properties. The stability, ferroelectricity and photocatalytic and photovoltaic properties of super-wurtzite Mg2XN3 (X = Bi, Mo, Nb, Sb, Ta, Tc and W) were determined based on first principles calculations in this study. The calculated results indicate that Mg2XN3 (X = Sb, Ta, Bi and Nb) are stable polar nitrides by phonon frequencies, elastic coefficients and ferroelectric analysis. Mg2XN3 (X = Sb, Ta and Nb) with large ferroelectric polarization strength could absorb ultraviolet light to promote photocatalytic water splitting for hydrogen production. Mg2BiN3 is a new excellent photovoltaic candidate due to its ideal energy band, high electron mobility, high absorption coefficient and large ferroelectric polarization strength.

8.
BMC Cancer ; 21(1): 1117, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663242

RESUMO

BACKGROUND: Preoperative serum gamma-glutamyl transferase (γ-GT) levels is significantly related to the prognosis of hepatocellular carcinoma (HCC), but its clinical value in the management of postoperative adjuvant transarterial chemoembolization (PA-TACE) has rarely been explored. This study aimed to investigate whether γ-GT levels could be taken as a biomarker to guide the management of PA-TACE in resectable HCC. METHODS: HCC patients receiving radical resection were identified through the primary liver cancer big data (PLCBD) from December 2012 to December 2015. Prognostic factors of overall survival (OS) and disease-free survival (DFS) were identified by univariate and multivariate cox analyses, and subgroup analysis was conducted between PA-TACE group and non-TACE stratified by γ-GT levels before and after 1:1 propensity score matching (PSM). RESULTS: γ-GT level was found to be an independent risk factor of OS and DFS in 1847 HCC patients receiving radical resection (both P < 0.05), and patients with elevated γ-GT(> 54.0 U/L) have a shortened median OS and DFS, compared with those with normal γ-GT (both P < 0.001). In the subgroup of patients with normal γ-GT, there were no significant differences between groups of PA-TACE and non-TACE in terms of median OS and DFS before and after PSM (all P > 0.05), and PA-TACE was not a significant prognostic factor of both OS and DFS before and after PSM (all P > 0.05). In the subgroup of patients with elevated γ-GT, significant differences were found between groups of PA-TACE and non-TACE in terms of median OS and DFS before and after PSM (all P < 0.05), and PA-TACE was an independent prognostic factor of both OS and DFS (all P < 0.05). CONCLUSION: Currently, we concluded that patients with more advanced HCC also have more elevated γ-GT, and these patients with elevated γ-GT would be benefited more from PA-TACE after radical resection.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/enzimologia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/enzimologia , gama-Glutamiltransferase/sangue , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios/métodos , Período Pré-Operatório , Pontuação de Propensão , Modelos de Riscos Proporcionais , Fatores de Risco
9.
Molecules ; 26(19)2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34641315

RESUMO

Essential oils (EOs) have been used in cosmetics and food due to their antimicrobial and antiviral effects. However, the applications of EOs are compromised because of their poor aqueous solubility and high volatility. Qiai (Artemisia argyi Levl. et Van. var. argyi cv. Qiai) is a traditional Chinese herb and possesses strong antibacterial activity. Herein, we report an innovative formulation of EO as nanohydrogels, which were prepared through co-assembly of Qiai EO (QEO) and Pluronic F108 (PEG-b-PPG-b-PEG, or PF108) in aqueous solution. QEO was efficiently loaded in the PF108 micelles and formed nanohydrogels by heating the QEO/PF108 mixture solution to 37 °C, by the innate thermo-responsive property of PF108. The encapsulation efficiency and loading capacity of QEO reached 80.2% and 6.8%, respectively. QEO nanohydrogels were more stable than the free QEO with respect to volatilization. Sustained QEO release was achieved at body temperature using the QEO nanohydrogels, with the cumulative release rate reaching 95% in 35 h. In vitro antibacterial test indicated that the QEO nanohydrogels showed stronger antimicrobial activity against S. aureus and E. coli than the free QEO due to the enhanced stability and sustained-release characteristics. It has been attested that thermo-responsive QEO nanohydrogels have good potential as antibacterial cosmetics.


Assuntos
Antibacterianos/síntese química , Artemisia/química , Escherichia coli/crescimento & desenvolvimento , Óleos Voláteis/síntese química , Staphylococcus aureus/crescimento & desenvolvimento , Antibacterianos/química , Antibacterianos/farmacologia , Preparações de Ação Retardada , Composição de Medicamentos , Escherichia coli/efeitos dos fármacos , Micelas , Viabilidade Microbiana/efeitos dos fármacos , Nanopartículas/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Tamanho da Partícula , Extratos Vegetais/química , Poloxâmero/química , Staphylococcus aureus/efeitos dos fármacos , Termodinâmica
10.
J Neuroinflammation ; 17(1): 99, 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32241292

RESUMO

BACKGROUND: Bladder-related pain symptoms in patients with bladder pain syndrome/interstitial cystitis (BPS/IC) are often accompanied by depression and memory deficits. Magnesium deficiency contributes to neuroinflammation and is associated with pain, depression, and memory deficits. Neuroinflammation is involved in the mechanical allodynia of cyclophosphamide (CYP)-induced cystitis. Magnesium-L-Threonate (L-TAMS) supplementation can attenuate neuroinflammation. This study aimed to determine whether and how L-TAMS influences mechanical allodynia and accompanying depressive symptoms and memory deficits in CYP-induced cystitis. METHODS: Injection of CYP (50 mg/kg, intraperitoneally, every 3 days for 3 doses) was used to establish a rat model of BPS/IC. L-TAMS was administered in drinking water (604 mg·kg-1·day-1). Mechanical allodynia in the lower abdomen was assessed with von Frey filaments using the up-down method. Forced swim test (FST) and sucrose preference test (SPT) were used to measure depressive-like behaviors. Novel object recognition test (NORT) was used to detect short-term memory function. Concentrations of Mg2+ in serum and cerebrospinal fluid (CSF) were measured by calmagite chronometry. Western blot and immunofluorescence staining measured the expression of tumor necrosis factor-α/nuclear factor-κB (TNF-α/NF-κB), interleukin-1ß (IL-1ß), and N-methyl-D-aspartate receptor type 2B subunit (NR2B) of the N-methyl-D-aspartate receptor in the L6-S1 spinal dorsal horn (SDH) and hippocampus. RESULTS: Free Mg2+ was reduced in the serum and CSF of the CYP-induced cystitis rats on days 8, 12, and 20 after the first CYP injection. Magnesium deficiency in the serum and CSF correlated with the mechanical withdrawal threshold, depressive-like behaviors, and short-term memory deficits (STMD). Oral application of L-TAMS prevented magnesium deficiency and attenuated mechanical allodynia (n = 14) and normalized depressive-like behaviors (n = 10) and STMD (n = 10). The upregulation of TNF-α/NF-κB signaling and IL-1ß in the L6-S1 SDH or hippocampus was reversed by L-TAMS. The change in NR2B expression in the SDH and hippocampus in the cystitis model was normalized by L-TAMS. CONCLUSIONS: Normalization of magnesium deficiency by L-TAMS attenuated mechanical allodynia, depressive-like behaviors, and STMD in the CYP-induced cystitis model via inhibition of TNF-α/NF-κВ signaling and normalization of NR2B expression. Our study provides evidence that L-TAMS may have therapeutic value for treating pain and comorbid depression or memory deficits in BPS/IC patients.


Assuntos
Butiratos/uso terapêutico , Cistite/complicações , Hiperalgesia/tratamento farmacológico , Deficiência de Magnésio/tratamento farmacológico , Transtornos da Memória/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Animais , Butiratos/farmacologia , Ciclofosfamida/efeitos adversos , Cistite/induzido quimicamente , Cistite/metabolismo , Cistite/fisiopatologia , Modelos Animais de Doenças , Feminino , Hiperalgesia/etiologia , Hiperalgesia/metabolismo , Hiperalgesia/fisiopatologia , Deficiência de Magnésio/complicações , Deficiência de Magnésio/metabolismo , Deficiência de Magnésio/fisiopatologia , Transtornos da Memória/etiologia , Transtornos da Memória/metabolismo , Transtornos da Memória/fisiopatologia , NF-kappa B/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Fator de Necrose Tumoral alfa/metabolismo
11.
Neurourol Urodyn ; 38(5): 1250-1260, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30989724

RESUMO

AIMS: Central sensitization playsimportant roles in cyclophosphamide (CYP)-induced cystitis. In addition, as a visceral pain, CYP-induced chronic pain shares common pathophysiological mechanisms with neuropathic pain. Previous studies demonstrated that neuregulin-1 (Nrg1)-ErbB signaling contributes to neuropathic pain, but whether and how this signaling influences mechanical allodynia in CYP-induced cystitis is unclear. This study aimed to determine whether and how Nrg1-ErbB signaling modulates mechanical allodynia in a CYP-induced cystitis rat model. METHODS: Systemic injection with CYP was used to establish a rat model of bladder pain syndrome/interstitial cystitis (BPS/IC). An irreversible ErbB family receptor inhibitor, PD168393, and exogenous Nrg1 were intrathecally injected to modulate Nrg1-ErbB signaling. Mechanical allodynia in the lower abdomen was assessed with von-Frey filaments using the up-down method. Western blot analysis and immunofluorescence staining were used to measure the expression of Nrg1-ErbB signaling, Iba-1, p-p38, and IL-1ß in the L6-S1 spinal dorsal horn (SDH). RESULTS: We observed upregulation of Nrg1-ErbB signaling as well as overexpression of the microglia activation markers Iba-1 and p-p38 and the proinflammatory factor, interleukin-1ß (IL-1ß), in the SDH of the cystitis group. Further, treatment with PD168393 attenuated mechanical allodynia in CYP-induced cystitis and inhibited microglia activation, leading to decreased production of IL-1ß. The inhibitor PD168393 reversed the algesic effect of exogenous Nrg1 on the cystitis model. CONCLUSIONS: Nrg1-ErbB signaling may promote microglia activation, contributing to mechanical allodynia of CYP-induced cystitis. Our study showed that modulation of Nrg1-ErbB signaling may have therapeutic value for treating pain symptoms in BPS/IC.


Assuntos
Cistite/induzido quimicamente , Hiperalgesia/induzido quimicamente , Microglia , Neuregulina-1/fisiologia , Proteínas Oncogênicas v-erbB/fisiologia , Animais , Cistite/complicações , Cistite/tratamento farmacológico , Feminino , Hiperalgesia/tratamento farmacológico , Hiperalgesia/etiologia , Injeções Espinhais , Ativação de Macrófagos , Quinazolinas/farmacologia , Quinazolinas/uso terapêutico , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
12.
Circulation ; 133(11): 1081-92, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26841808

RESUMO

BACKGROUND: Adult mammalian cardiomyocytes (CMs) have the potential to proliferate, but this is not sufficient to generate adequate CMs after myocardial infarction (MI). The transcription factor Tbx20 is required for CM proliferation during development and adult CM homeostasis. The ability of Tbx20 overexpression (Tbx20(OE)) to promote adult CM proliferation and to improve cardiac function after MI was examined. METHODS AND RESULTS: Tbx20(OE) was induced specifically in adult mouse differentiated CMs. Increased CM proliferation and fetal-like characteristics were found in Tbx20(OE) hearts compared with controls without causing pathology 4 weeks after Tbx20(OE) at baseline. Moreover, Tbx20(OE) in adult CM after MI significantly improved survival, cardiac function, and infarct size 4 weeks after MI. Improved cardiac repair, as indicated by increased CM proliferation and capillary density, was observed in the MI border zone of Tbx20(OE) hearts compared with controls. Expression of proliferation activator (cyclin D1, E1, and IGF1) and fetal contractile protein (ssTNI, ßMHC) mRNA was increased whereas negative cell-cycle regulators (p21, Meis1) were decreased in Tbx20(OE) hearts compared with controls under both baseline and MI conditions. Tbx20(OE) in adult hearts activates multiple proproliferation pathways, including Akt, YAP and BMP. Interestingly, p21, Meis1, and a novel cell-cycle inhibitory gene, Btg2, are directly bound and repressed by Tbx20 with induction of proliferation in neonatal CM. CONCLUSIONS: Tbx20(OE), specifically in adult CM, activates multiple cardiac proliferative pathways, directly represses cell-cycle inhibitory genes p21, Meis1, and Btg2, promotes adult CM proliferation; and preserves cardiac performance after MI.


Assuntos
Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas com Domínio T/fisiologia , Animais , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Divisão Celular , Tamanho Celular/efeitos dos fármacos , Eletrocardiografia , Feminino , Proteínas Fetais/biossíntese , Proteínas Fetais/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Genes cdc/efeitos dos fármacos , Coração/fisiopatologia , Proteínas Imediatamente Precoces/biossíntese , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/fisiologia , Camundongos , Camundongos Transgênicos , Proteínas Musculares/biossíntese , Proteínas Musculares/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Miócitos Cardíacos/patologia , Tamanho do Órgão/efeitos dos fármacos , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Distribuição Aleatória , Transdução de Sinais/efeitos dos fármacos , Método Simples-Cego , Proteínas com Domínio T/biossíntese , Proteínas com Domínio T/genética , Tamoxifeno/farmacologia , Proteínas Supressoras de Tumor/biossíntese , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/fisiologia
13.
J Mol Cell Cardiol ; 91: 23-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26718723

RESUMO

The majority of cardiac fibroblasts in a mature mammalian heart are derived from the epicardium during prenatal development and reactivate developmental programs during the progression of fibrotic disease. In addition, epicardial activation, proliferation, and fibrosis occur with ischemic, but not hypertensive injury. Here we review cellular and molecular mechanisms that control epicardium-derived cell lineages during development and disease with a focus on cardiac fibroblasts. This article is part of a special issue entitled "Fibrosis and Myocardial Remodeling".


Assuntos
Fibroblastos/patologia , Infarto do Miocárdio/patologia , Miócitos Cardíacos/patologia , Pericárdio/patologia , Animais , Diferenciação Celular , Linhagem da Célula/fisiologia , Proliferação de Células , Fibroblastos/metabolismo , Fibrose , Humanos , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Organogênese/fisiologia , Pericárdio/metabolismo
15.
Opt Express ; 24(18): 20297-308, 2016 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-27607636

RESUMO

The molecular multiple rescattering processes have been theoretically investigated via solving the time-dependent Schrödinger equation. Not only has the physical model been established, but also the related rescatterings originating from recombination with parent nucleus and with neighboring nucleus have been distinguished. Moreover, it has shown that the rescatterings originating from recombination with parent nucleus are similar with those atomic rescatterings, while those rescatterings from recombination with neighboring nucleus both before and after reversing the direction of the laser field are more sensitive to the internuclear distance. With time-frequency distribution and classical electron dynamics, the underlying mechanisms are revealed.

16.
Z Naturforsch C J Biosci ; 71(5-6): 181-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27049618

RESUMO

Ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO) is the key enzyme to assimilate CO(2) into the biosphere. The nonredundant structural data sets for three RuBisCO domain superfamilies, i.e. large subunit C-terminal domain (LSC), large subunit N-terminal domain (LSN) and small subunit domain (SS), were selected using QR factorization based on the structural alignment with QH as the similarity measure. The structural phylogenies were then constructed to investigate a possible functional significance of the evolutionary diversification. The LSC could have occurred in both bacteria and archaea, and has evolved towards increased complexity in both bacteria and eukaryotes with a 4-helix-2-helix-2-helix bundle being extended into a 5-helix-3-helix-3-helix one at the LSC carboxyl-terminus. The structural variations of LSN could have originated not only in bacteria with a short coil, but also in eukaryotes with a long one. Meanwhile, the SS dendrogram can be contributed to the structural variations at the ßA-ßB-loop region. All the structural variations observed in the coil regions have influence on catalytic performance or CO(2)/O(2) selectivities of RuBisCOs from different species. Such findings provide insights on RuBisCO improvements.


Assuntos
Evolução Molecular , Ribulose-Bifosfato Carboxilase/química , Ribulose-Bifosfato Carboxilase/genética , Motivos de Aminoácidos , Domínio Catalítico
17.
J Virol ; 88(19): 11469-79, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25056890

RESUMO

UNLABELLED: Japanese encephalitis (JE) is an arthropod-borne disease associated with the majority of viral encephalitis cases in the Asia-Pacific region. The causative agent, Japanese encephalitis virus (JEV), has been phylogenetically divided into five genotypes. Recent surveillance data indicate that genotype I (GI) is gradually replacing genotype III (GIII) as the dominant genotype. To investigate the mechanism behind the genotype shift and the potential consequences in terms of vaccine efficacy, human cases, and virus dissemination, we collected (i) all full-length and partial JEV molecular sequences and (ii) associated genotype and host information comprising a data set of 873 sequences. We then examined differences between the two genotypes at the genetic and epidemiological level by investigating amino acid mutations, positive selection, and host range. We found that although GI is dominant, it has fewer sites predicted to be under positive selection, a narrower host range, and significantly fewer human isolates. For the E protein, the sites under positive selection define a haplotype set for each genotype that shows striking differences in their composition and diversity, with GIII showing significantly more variety than GI. Our results suggest that GI has displaced GIII by achieving a replication cycle that is more efficient but is also more restricted in its host range. IMPORTANCE: Japanese encephalitis is an arthropod-borne disease associated with the majority of viral encephalitis cases in the Asia-Pacific region. The causative agent, Japanese encephalitis virus (JEV), has been divided into five genotypes based on sequence similarity. Recent data indicate that genotype I (GI) is gradually replacing genotype III (GIII) as the dominant genotype. Understanding the reasons behind this shift and the potential consequences in terms of vaccine efficacy, human cases, and virus dissemination is important for controlling the spread of the virus and reducing human fatalities. We collected all available full-length and partial JEV molecular sequences and associated genotype and host information. We then examined differences between the two genotypes at the genetic and epidemiological levels by investigating amino acid mutations, positive selection, and host range. Our results suggest that GI has displaced GIII by achieving a replication cycle that is more efficient but more restricted in host range.


Assuntos
Culicidae/virologia , Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/epidemiologia , Genótipo , Insetos Vetores/virologia , Filogenia , Animais , Ásia/epidemiologia , Ceratopogonidae , Quirópteros , Reservatórios de Doenças , Vírus da Encefalite Japonesa (Espécie)/classificação , Encefalite Japonesa/virologia , Cavalos , Especificidade de Hospedeiro , Interações Hospedeiro-Patógeno , Humanos , Modelos Moleculares , RNA Viral/genética , Sorotipagem , Suínos
18.
Eur Heart J ; 35(14): 920-31, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23048191

RESUMO

AIMS: Hypoplastic coronary artery disease is a rare congenital abnormality that is associated with sudden cardiac death. However, molecular mechanisms responsible for this disease are not clear. The aim of the present study was to assess the role of nitric oxide synthase-3 (NOS3) in the pathogenesis of hypoplastic coronary arteries. METHODS AND RESULTS: Wild-type (WT), NOS3(-/-), and a novel cardiac-specific NOS3 overexpression mouse model were employed. Deficiency in NOS3 resulted in coronary artery hypoplasia in foetal mice and spontaneous myocardial infarction in postnatal hearts. Coronary artery diameters, vessel density, and volume were significantly decreased in NOS3(-/-) mice at postnatal day 0. In addition, NOS3(-/-) mice showed a significant increase in the ventricular wall thickness, myocardial volume, and cardiomyocyte cell size compared with WT mice. Lack of NOS3 also down-regulated the expression of Gata4, Wilms tumour-1, vascular endothelial growth factor, basic fibroblast growth factor and erythropoietin, and inhibited migration of epicardial cells. These abnormalities and hypoplastic coronary arteries in the NOS3(-/-) mice were completely rescued by the cardiac-specific overexpression of NOS3. CONCLUSION: Nitric oxide synthase-3 is required for coronary artery development and deficiency in NOS3 leads to hypoplastic coronary arteries.


Assuntos
Anomalias dos Vasos Coronários/enzimologia , Infarto do Miocárdio/enzimologia , Óxido Nítrico Sintase Tipo III/deficiência , Animais , Animais Recém-Nascidos , Anomalias dos Vasos Coronários/embriologia , Camundongos Transgênicos , Infarto do Miocárdio/embriologia , Análise de Sobrevida
19.
J Huazhong Univ Sci Technolog Med Sci ; 35(1): 82-86, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25673198

RESUMO

Formaldehyde (FA) is a ubiquitous toxic organic compound, and it has been regarded as a leukemogen. However, the mechanisms by which FA induces bone marrow toxicity remain unclear. The present study was aimed to examine the bone marrow toxicity caused by FA and the mechanism involving the expression changes of peroxiredoxin3 (Prx3) in this process. The mice were divided into four groups with 6 mice per group. Animals in the control group were exposed to ambient air and those in the FA groups to different concentrations of FA (20, 40, 80 mg/m(3)) for 15 days in the separate inhalation chambers, 2 h a day. At the end of the 15-day experimental period, all mice were killed. Bone marrow cells were obtained. The level of hydrogen peroxide (H2O2), the apoptosis rate, and the activities and protein expression levels of caspase-3 and caspase-9 were determined by biochemical assay, flow cytometry and immunohistochemistry, respectively; DNA damage and Prx3 expression levels were measured by single cell gel eletrophoresis immunohistochemistry and Western blotting, respectively. The results showed that the H2O2 level and cell apoptosis rate were significantly increased in FA groups relative to the control group. Caspase-3 and caspase-9 activities and their protein expression levels were markedly increased as well. Additionally, FA also increased the rate of DNA damage and the expression level of Prx3 compared with control group. Our study suggested that a certain concentration of FA causes the bone marrow toxicity by regulating the expression of Prx3.


Assuntos
Medula Óssea/efeitos dos fármacos , Formaldeído/farmacologia , Proteínas de Homeodomínio/metabolismo , Animais , Western Blotting , Medula Óssea/metabolismo , Masculino , Camundongos
20.
Urol Int ; 92(2): 202-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24458144

RESUMO

OBJECTIVES: Although evidence supports a role for inflammation in interstitial cystitis/bladder pain syndrome (IC/BPS), the mechanism remains unknown. We determined whether inflammation causes an elevated expression of nerve growth factor (NGF) and transient receptor potential vanilloid receptor subtype 1 (TRPV1) and correlated them with the symptoms. METHODS: Bladder biopsies were obtained from 53 IC/BPS patients and 27 controls, and hematoxylin and eosin staining, immunostaining and Western blotting were performed to detect inflammation, TRPV1-immunoreactive and PGP9.5-immunoreactive nerve fibers, and NGF, respectively. Symptoms were assessed using the Pelvic Pain/Urgency/Frequency (PUF) questionnaire and pain visual analogue scale scores. Suburothelial nerve fiber density was quantified and correlated with PUF scores. RESULTS: Increased severity of inflammation was correlated with a higher TRPV1-immunoreactive nerve fiber density (r = 0.4113, p = 0.0024) and higher NGF levels (r = 0.3775, p = 0.0052). Suburothelial TRPV1-immunoreactive nerve fiber density was significantly correlated with pain scores and urgency scores (r = 0.3320, p = 0.0145 and r = 0.3823, p = 0.0039, respectively). PGP9.5-immunoreactive nerve fibers were significantly increased in IC/BPS (p = 0.0193) and had a positive relationship with inflammation severity (r = 0.6138, p < 0.0001). CONCLUSIONS: Our study revealed increased severity of inflammation correlated with a higher expression of TRPV1-immunoreactive nerve fibers and NGF in IC/BPS and correlated with clinical symptoms.


Assuntos
Cistite Intersticial/metabolismo , Fator de Crescimento Neural/metabolismo , Dor/metabolismo , Canais de Cátion TRPV/metabolismo , Doenças da Bexiga Urinária/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Feminino , Regulação da Expressão Gênica , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
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