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1.
Ecotoxicol Environ Saf ; 262: 115331, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37556956

RESUMEN

Acetaminophen (APAP) overdose has long been considered a major cause of drug-induced liver injury. Ferroptosis is a type of programmed cell death mediated by iron-dependent lipid peroxidation. Endoplasmic reticulum (ER) stress is a systemic response triggered by the accumulation of unfolded or misfolded proteins in the ER. Ferroptosis and ER stress have been proven to contribute to the progression of APAP-induced acute liver injury (ALI). It was reported that salidroside protects against APAP-induced ALI, but the potential mechanism remain unknown. In this study, male C57BL/6 J mice were intraperitoneally (i.p.) injected APAP (500 mg/kg) to induce an ALI model. Salidroside was i.p. injected at a dose of 100 mg/kg 2 h prior to APAP administration. Mice were sacrificed 12 h after APAP injection and the liver and serum of the mice were obtained for histological and biochemistry analysis. AML12 cells were used in in vitro assays. The results indicated that salidroside mitigated glutathione degradation via inhibiting cation transport regulator homolog 1 (CHAC1) to attenuate ferroptosis, and simultaneously suppressing PERK-eIF2α-ATF4 axis-mediated ER stress, thus alleviating APAP-induced ALI. However, PERK activator CCT020312 and overexpression of ATF4 inhibited the protective function of salidroside on CHAC1-mediated ferroptosis. Besides this, activation of the AMPK/SIRT1 signaling pathway by salidroside was demonstrated to have a protective effect against APAP-induced ALI. Interestingly, selective inhibition of SIRT1 ameliorated the protective effects of salidroside on ER stress and ferroptosis. Overall, salidroside plays a significant part in the mitigation of APAP-induced ALI by activating the AMPK/SIRT1 signaling to inhibit ER stress-mediated ferroptosis in the ATF4-CHAC1 axis.

2.
Plant J ; 107(5): 1420-1431, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34171163

RESUMEN

The phycobilisomes (PBSs) of cyanobacteria and red-algae are unique megadaltons light-harvesting protein-pigment complexes that utilize bilin derivatives for light absorption and energy transfer. Recently, the high-resolution molecular structures of red-algal PBSs revealed how the multi-domain core-membrane linker (LCM ) specifically organizes the allophycocyanin subunits in the PBS's core. But, the topology of LCM in these structures was different than that suggested for cyanobacterial PBSs based on lower-resolution structures. Particularly, the model for cyanobacteria assumed that the Arm2 domain of LCM connects the two basal allophycocyanin cylinders, whereas the red-algal PBS structures revealed that Arm2 is partly buried in the core of one basal cylinder and connects it to the top cylinder. Here, we show by biochemical analysis of mutations in the apcE gene that encodes LCM , that the cyanobacterial and red-algal LCM topologies are actually the same. We found that removing the top cylinder linker domain in LCM splits the PBS core longitudinally into two separate basal cylinders. Deleting either all or part of the helix-loop-helix domain at the N-terminal end of Arm2, disassembled the basal cylinders and resulted in degradation of the part containing the terminal emitter, ApcD. Deleting the following 30 amino-acids loop severely affected the assembly of the basal cylinders, but further deletion of the amino-acids at the C-terminal half of Arm2 had only minor effects on this assembly. Altogether, the biochemical data are consistent with the red-algal LCM topology, suggesting that the PBS cores in cyanobacteria and red-algae assemble in the same way.


Asunto(s)
Proteínas Bacterianas/química , Complejos de Proteína Captadores de Luz/química , Modelos Moleculares , Ficobilisomas/química , Ficocianina/química , Synechocystis/genética , Proteínas Bacterianas/metabolismo , Transferencia de Energía , Complejos de Proteína Captadores de Luz/metabolismo , Mutación , Ficobilisomas/metabolismo , Ficocianina/metabolismo , Dominios Proteicos , Rhodophyta , Synechocystis/química , Synechocystis/metabolismo
3.
Ann Surg Oncol ; 29(6): 3963-3976, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35266081

RESUMEN

BACKGROUND: Concise and precise prognostic models are urgently needed due to the intricate genetic variations among hepatocellular carcinoma (HCC) cells. Disorder or change in glycolysis metabolism has been considered one of the "hallmarks" of cancer. However, the prognostic value of glycolysis-related genes in HCC remains elusive. METHODS: A multigene prognostic model was constructed by least absolute shrinkage and selection operator Cox regression analysis in the The Cancer Genome Atlas (TCGA) cohort with 365 HCC patients and validated in the International Cancer Genome Consortium (ICGC) cohort with 231 HCC patients. The Kaplan-Meier methodology and time-dependent receiver operating characteristic curve were employed to confirm its predictive capability. A predictive nomogram was established based on the stepwise multivariate regression model. The differential expression of prognostic genes between HCC tissues and normal tissues was verified by quantitative real-time polymerase chain reaction (PCR) and immunohistochemistry in an independent sample cohort with 30 HCC patients. RESULTS: The glycolysis-related gene signature and the nomogram model exhibited robust validity in predicting prognosis. The risk score was an independent predictor for overall survival (OS). Expression levels of immune checkpoint genes and cell cycle genes were significantly elevated in the high-risk group. The high-risk group presented high levels of immune exclusion. The risk score can distinguish the effect of immunotherapy in the IMvigor210 cohort. The prognostic gene expression showed a significant difference between HCC tissues and adjacent nontumorous tissues in the independent sample cohort. CONCLUSION: The currently established glycolysis-related gene signature can accurately predict prognosis and reflect immune status, which may be a therapeutic alternative.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/patología , Perfilación de la Expresión Génica , Glucólisis/genética , Humanos , Neoplasias Hepáticas/patología , Pronóstico
4.
Ecotoxicol Environ Saf ; 214: 112099, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33714139

RESUMEN

Although fish are widely confirmed to be susceptible to heavy metals (HMs) contamination in sediments, this bioconversion haven't been detailed. This is especially the case in karst areas, where HMs are less stably retained in the sediments and are more bioavailable. Therefore, we surveyed representative karst rivers in Liuzhou, China, in order to study the relationship between the speciations of seven HMs in the sediments with their bioaccumulation in wild fish. The results showed that the HMs in sediments are all below their permissible exposure limit (PEL), but Cd and Zn are significantly higher than soil basline. Most HMs are in residual fraction, while their exchangeable fractions are present in extremely low proportions. The concentration of Zn, Cr and Cd in some fish are above their maximum recommended limit (MRL). The concentrations of most of the HMs in the fish are significantly correlated with the levels in the sediments and given the higher correlation coefficients for their carbonate-bound phase, this phase can be seen to play a critical role in HMs bioconversion. However, the presence of this phase in low proportions enables other phases, especially oxidizable form, to play a greater role in HMs bioaccumulation. Apart from Do, HMs in the fish samples are significantly correlated with multiple environmental factors, demonstrating environmental fluctuations can manipulate HMs bioconversion from sediments; however, their significance depend heavily on the proportion of particular species. HMs in reducible and oxidizable fraction are more important in regulating, rather than promoting, their bioconversion during environmental fluctuations. Fluctuations in EC, TDS and pH can increase the impacts of HMs in carbonate-bound fraction on their bioconversion. Given the higher background values of EC and TDS and lower pH values during the monsoon period, careful attention should be paid to the increased bioconversion of HMs in karst rivers during this season.


Asunto(s)
Monitoreo del Ambiente , Peces/fisiología , Metales Pesados/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Bioacumulación , China , Sedimentos Geológicos , Metales Pesados/análisis , Medición de Riesgo , Ríos , Estaciones del Año , Suelo , Contaminantes Químicos del Agua/análisis
5.
Molecules ; 24(11)2019 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-31174300

RESUMEN

In this study, two phenol compounds, magnolol and honokiol, were extracted from Magnolia officinalis and identified by LC-MS, 1H- and 13C-NMR. The magnolol and honokiol were shown to be effective against seven pathogenic fungi, including Alternaria alternata (Fr.) Keissl, Penicillium expansum (Link) Thom, Alternaria dauci f.sp. solani, Fusarium moniliforme J. Sheld, Fusarium oxysporum Schltdl., Valsa mali Miyabe & G. Yamada, and Rhizoctonia solani J.G. Kühn, with growth inhibition of more than 57%. We also investigated the mechanisms underlying the potential antifungal activity of magnolol and honokiol. The results showed that they inhibited the growth of A. alternata in a dose-dependent manner. Moreover, magnolol and honokiol treatment resulted in distorted mycelia and increased the cell membrane permeability of A. alternata, as determined by conductivity measurements. These results suggest that magnolol and honokiol are potential antifungal agents for application against plant fungal diseases.


Asunto(s)
Compuestos de Bifenilo/química , Compuestos de Bifenilo/farmacología , Lignanos/química , Lignanos/farmacología , Magnolia/efectos de los fármacos , Enfermedades de las Plantas/microbiología , Alternaria/efectos de los fármacos , Alternaria/patogenicidad , Antifúngicos/química , Antifúngicos/farmacología , Magnolia/química , Nicotiana/efectos de los fármacos , Nicotiana/microbiología
6.
Biochim Biophys Acta Mol Cell Res ; 1864(10): 1877-1886, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28782566

RESUMEN

Biliproteins have extended the spectral range of fluorescent proteins into the region of maximal transmission of most tissues and are favorable for multiplexing, but their application presents considerable challenges. Their fluorescence derives from open-chain tetrapyrrole chromophores which often require the introduction of dedicated reductases and lyases. In addition, their fluorescence yield generally decreases with increasing wavelengths and depends strongly on the state of the binding protein. We report fluorescent biliproteins, termed BDFPs, that are derived from the phycobilisome core subunit, ApcF2: this subunit is induced in the thermophilic cyanobacterium, Chroococcidiopsis thermalis, by far-red light and binds phycocyanobilin non-covalently. The BDFPs obtained by molecular evolution of ApcF2 bind the more readily accessible biliverdin covalently while retaining the red-shifted fluorescence in the near-infrared spectral region (~710nm). They are small monomers (~15kDa) and not only show excellent photostability, but are also thermostable up to 80°C, tolerate acid down to pH2 and high concentrations of denaturants. The result indicates far-red adapting cyanobacteria as a useful source for designing extremely red-shifted fluorescent markers. In vivo performance of BDFPs as biomarkers in conventional and super-resolution microscopy, alone or fused to target proteins, is exemplified in several mammalian cells, including, human cell lines, in the nematode, Caenorhabditis elegans and, at low pH, in Lactobacillus lactis.


Asunto(s)
Proteínas Bacterianas/química , Ficobiliproteínas/química , Ficobilisomas/metabolismo , Proteínas Bacterianas/metabolismo , Cianobacterias/química , Fluorescencia , Humanos , Luz , Ficobiliproteínas/metabolismo , Ficobilisomas/química , Espectrometría de Fluorescencia
7.
Biochim Biophys Acta ; 1857(6): 688-94, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27045046

RESUMEN

Phycobiliproteins that bind bilins are organized as light-harvesting complexes, phycobilisomes, in cyanobacteria and red algae. The harvested light energy is funneled to reaction centers via two energy traps, allophycocyanin B and the core-membrane linker, ApcE1 (conventional ApcE). The covalently bound phycocyanobilin (PCB) of ApcE1 absorbs near 660 nm and fluoresces near 675 nm. In cyanobacteria capable of near infrared photoacclimation, such as Synechococcus sp. PCC7335, there exist even further spectrally red shifted components absorbing >700 nm and fluorescing >710 nm. We expressed the chromophore domain of the extra core-membrane linker from Synechococcus sp. PCC7335, ApcE2, in E. coli together with enzymes generating the chromophore, PCB. The resulting chromoproteins, PCB-ApcE2(1-273) and the more truncated PCB-ApcE2(24-245), absorb at 700 nm and fluoresce at 714 nm. The red shift of ~40 nm compared with canonical ApcE1 results from non-covalent binding of the chromophore by which its full conjugation length including the Δ3,3(1) double bond is preserved. The extreme spectral red-shift could not be ascribed to exciton coupling: dimeric PCB-ApcE2(1-273) and monomeric-ApcE2(24-245) absorbed and fluoresced similarly. Chromophorylation of ApcE2 with phycoerythrobilin- or phytochromobilin resulted in similar red shifts (absorption at 615 and 711 nm, fluorescence at 628 or 726 nm, respectively), compared to the covalently bound chromophores. The self-assembled non-covalent chromophorylation demonstrates a novel access to red and near-infrared emitting fluorophores. Brightly fluorescent biomarking was exemplified in E. coli by single-plasmid transformation.


Asunto(s)
Proteínas Bacterianas/metabolismo , Fotosíntesis , Ficobilinas/metabolismo , Ficobilisomas/metabolismo , Ficocianina/metabolismo , Synechococcus/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Escherichia coli/genética , Microscopía Fluorescente , Modelos Moleculares , Ficobilinas/química , Ficobilinas/genética , Ficocianina/química , Ficocianina/genética , Ficoeritrina/química , Ficoeritrina/genética , Ficoeritrina/metabolismo , Multimerización de Proteína , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Espectrometría de Fluorescencia , Synechococcus/genética
8.
Biochim Biophys Acta ; 1857(9): 1607-1616, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27368145

RESUMEN

Cyanobacterial light-harvesting complexes, phycobilisomes, can undergo extensive remodeling under varying light conditions. Acclimation to far-red light involves not only generation of red-shifted chlorophylls in the photosystems, but also induction of additional copies of core biliproteins that have been related to red-shifted components of the phycobilisome (Gan et al., Life 5, 4, 2015). We are studying the molecular basis for these acclimations in Chroococcidiopsis thermalis sp. PCC7203. Five far-red induced allophycocyanin subunits (ApcA2, ApcA3, ApcB2, ApcB3 and ApcF2) were expressed in Escherichia coli, together with S-type chromophore-protein lyases and in situ generated chromophore, phycocyanobilin. Only one subunit, ApcF2, shows an unusual red-shift (λAmax~675nm, λFmax~698nm): it binds the chromophore non-covalently, thereby preserving its full conjugation length. This mechanism operates also in two Cys-variants of the induced subunits of bulky APC. All other wild-type subunits bind phycocyanobilin covalently to the conventional Cys-81 under catalysis of the lyase, CpcS1. Although three of them also show binding to additional cysteines, all absorb and fluoresce similar to conventional APC subunits (λAmax~610nm, λFmax~640nm). Another origin of red-shifted complexes was identified, however, when different wild-type α- and ß-subunits of the far-red induced bulky APC were combined in a combinatorial fashion. Strongly red-shifted complexes (λFmax≤722nm) were formed when the α-subunit, PCB-ApcA2, and the ß-subunit, PCB-ApcB2, were generated together in E. coli. This extreme aggregation-induced red-shift of ~90nm of covalently bound chromophores is reminiscent, but much larger, than the ~30nm observed with conventional APC.


Asunto(s)
Adaptación Fisiológica , Cianobacterias/química , Luz , Ficocianina/química , Sitios de Unión , Fluorescencia , Subunidades de Proteína
9.
Chem Biodivers ; 14(12)2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28960771

RESUMEN

Seven phenolic compounds, 1 - 7, including a new organic acid gallate, mucic acid 1-ethyl 6-methyl ester 2-O-gallate (7), were isolated from the MeOH extract of the fruits of Phyllanthus emblica L. (Euphorbiaceae). The structures were elucidated on the basis of extensive spectroscopic analysis and comparison with literature data. Upon evaluated for their antioxidant abilities by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. The inhibitory activities against melanogenesis in B16 melanoma cells induced by α-MSH, as well as cytotoxic activities against four human cancer cell lines were also evaluated. All phenolic compounds, 1 - 7, exhibited potent antioxidant abilities (DPPH: IC50 5.6 - 12.9 µm; ABTS: 0.87 - 8.43 µm Trolox/µm; FRAP: 1.01 - 5.79 µm Fe2+ /µm, respectively). Besides, 5 - 7, also exhibited moderate inhibitory activities against melanogenesis (80.7 - 86.8% melanin content), even with no or low toxicity to the cells (93.5 - 101.6% cell viability) at a high concentration of 100 µm. Compounds 1 - 3 exhibited cytotoxic activity against one or more cell lines (IC50 13.9 - 68.4%), and compound 1 with high tumor selectivity for A549 (SI 3.2).


Asunto(s)
Antineoplásicos Fitogénicos/química , Fenoles/química , Phyllanthus emblica/química , Células A549 , Animales , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/toxicidad , Antioxidantes/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Frutas/química , Frutas/metabolismo , Células HL-60 , Humanos , Espectroscopía de Resonancia Magnética , Melaninas/metabolismo , Ratones , Conformación Molecular , Fenoles/aislamiento & purificación , Fenoles/farmacología , Phyllanthus emblica/metabolismo , Extractos Vegetales/química
10.
Biomed Environ Sci ; 30(2): 106-112, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28292348

RESUMEN

OBJECTIVE: To develop a risk model for predicting later development of diabetic nephropathy (DN) in Chinese people with type 2 diabetes mellitus (T2DM) and evaluate its performance with independent validation. METHODS: We used data collected from the project 'Comprehensive Research on the Prevention and Control of Diabetes', which was a community-based study conducted by the Jiangsu Center for Disease Control and Prevention in 2013. A total of 11,771 eligible participants were included in our study. The endpoint was a clear diagnosis of DN. Data was divided into two components: a training set for model development and a test set for validation. The Cox proportional hazard regression was used for survival analysis in men and women. The model's performance was evaluated by discrimination and calibration. RESULTS: The incidence (cases per 10,000 person-years) of DN was 9.95 (95% CI; 8.66-11.43) in women and 11.28 (95% CI; 9.77-13.03) in men. Factors including diagnosis age, location, body mass index, high-density-lipoprotein cholesterol, creatinine, hypertension, dyslipidemia, retinopathy, diet control, and physical activity were significant in the final model. The model showed high discrimination and good calibration. CONCLUSION: The risk model for predicting DN in people with T2DM can be used in clinical practice for improving the quality of risk management and intervention.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/patología , Modelos Biológicos , Anciano , Pueblo Asiatico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Factores de Riesgo , Población Urbana
11.
J Pept Sci ; 22(11-12): 689-699, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27739168

RESUMEN

Cell-penetrating peptides (CPPs) have been shown to be potential drug carriers for cancer therapy. The inherently low immunogenicity and cytotoxicity of human-derived CPPs make them more suitable for intracellular drug delivery compared to other delivery vehicles. In this work, the protein transduction ability of a novel CPP (termed HBP) derived from the heparin-binding domain of HB-EGF was evaluated. Our data shows, for the first time, that HBP possesses similar properties to typical CPPs and is a potent drug delivery vector for improving the antitumor activity of impermeable MAP30. The intrinsic bioactivities of recombinant MAP30-HBP were well preserved compared to those of free MAP30. Furthermore, HBP conjugated to the C-terminus of MAP30 promoted the cellular uptake of recombinant MAP30-HBP. Moreover, the fusion of HBP to MAP30 gave rise to significantly enhanced cytotoxic effects in all of the tumor cell lines tested. In HeLa cells, this cytotoxicity was mainly caused by the induction of cell apoptosis. Further investigation revealed that HBP enhanced MAP30-induced apoptosis through the activation of the mitochondrial- and death receptor-mediated signaling pathways. In addition, the MAP30-HBP fusion protein caused more HeLa cells to become arrested in S phase compared to MAP30 alone. These results highlight the MAP30-HBP fusion protein as a promising drug candidate for cancer therapy and demonstrate HBP, a novel CPP derived from human HB-EGF, as a new potential vector for antitumor drug delivery. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.


Asunto(s)
Péptidos de Penetración Celular/farmacología , Portadores de Fármacos/farmacología , Factor de Crecimiento Similar a EGF de Unión a Heparina/farmacología , Proteínas Recombinantes de Fusión/farmacología , Proteínas Inactivadoras de Ribosomas Tipo 2/farmacología , Secuencia de Aminoácidos , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Péptidos de Penetración Celular/biosíntesis , Péptidos de Penetración Celular/genética , Clonación Molecular , Relación Dosis-Respuesta a Droga , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Células HeLa , Heparina/química , Heparina/metabolismo , Factor de Crecimiento Similar a EGF de Unión a Heparina/biosíntesis , Factor de Crecimiento Similar a EGF de Unión a Heparina/genética , Humanos , Momordica charantia/química , Unión Proteica , Dominios Proteicos , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética , Proteínas Inactivadoras de Ribosomas Tipo 2/biosíntesis , Proteínas Inactivadoras de Ribosomas Tipo 2/genética , Fase S/efectos de los fármacos , Transducción de Señal
12.
Chembiochem ; 15(8): 1190-9, 2014 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-24764310

RESUMEN

The gene slr1393 from Synechocystis sp. PCC6803 encodes a protein composed of three GAF domains, a PAS domain, and a histidine kinase domain. GAF3 is the sole domain able to bind phycocyanobilin (PCB) as chromophore and to accomplish photochemistry: switching between a red-absorbing parental and a green-absorbing photoproduct state (λmax =649 and 536 nm, respectively). Conversions in both directions were followed by time-resolved absorption spectroscopy with the separately expressed GAF3 domain of Slr1393. Global fit analysis of the recorded absorbance changes yielded three lifetimes (3.2 µs, 390 µs, and 1.5 ms) for the red-to-green conversion, and 1.2 µs, 340 µs, and 1 ms for the green-to-red conversion. In addition to the wild-type (WT) protein, 24 mutated proteins were studied spectroscopically. The design of these site-directed mutations was based on sequence alignments with related proteins and by employing the crystal structure of AnPixJg2 (PDB ID: 3W2Z), a Slr1393 orthologous from Anabaena sp. PCC7120. The structure of AnPixJg2 was also used as template for model building, thus confirming the strong structural similarity between the proteins, and for identifying amino acids to target for mutagenesis. Only amino acids in close proximity to the chromophore were exchanged, as these were considered likely to have an impact on the spectral and dynamic properties. Three groups of mutants were found: some showed absorption features similar to the WT protein, a second group showed modified absorbance properties, and the third group had lost the ability to bind the chromophore. The most unexpected result was obtained for the exchange at residue 532 (N532Y). In vivo assembly yielded a red-absorbing, WT-like protein. Irradiation, however, not only converted it into the green-absorbing form, but also produced a 660 nm, further-red-shifted absorbance band. This photoproduct was fully reversible to the parental form upon green light irradiation.


Asunto(s)
Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Ficobilinas/metabolismo , Ficocianina/metabolismo , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Synechocystis/química , Proteínas Bacterianas/genética , Histidina Quinasa , Cinética , Modelos Moleculares , Conformación Molecular , Mutagénesis Sitio-Dirigida , Ficobilinas/química , Ficocianina/química , Proteínas Quinasas/química , Estructura Terciaria de Proteína
13.
Photochem Photobiol Sci ; 13(5): 757-63, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24604419

RESUMEN

Cyanobacteriochromes are a structurally and spectrally highly diverse class of phytochrome-related photosensory biliproteins. They contain one or more GAF domains that bind phycocyanobilin (PCB) autocatalytically; some of these proteins are also capable of further modifying PCB to phycoviolobilin or rubins. We tested the chromophorylation with the non-photochromic phycoerythrobilin (PEB) of 16 cyanobacteriochrome GAFs from Nostoc sp. PCC 7120, of Slr1393 from Synechocystis sp. PCC 6803, and of Tlr0911 from Thermosynechococcus elongatus BP-1. Nine GAFs could be autocatalytically chromophorylated in vivo/in E. coli with PEB, resulting in highly fluorescent biliproteins with brightness comparable to that of fluorescent proteins like GFP. In several GAFs, PEB was concomitantly converted to phycourobilin (PUB) during binding. This not only shifted the spectra, but also increased the Stokes shift. The chromophorylated GAFs could be oligomerized further by attaching a GCN4 leucine zipper domain, thereby enhancing the absorbance and fluorescence of the complexes. The presence of both PEB and PUB makes these oligomeric GAF-"bundles" interesting models for energy transfer akin to the antenna complexes found in cyanobacterial phycobilisomes. The thermal and photochemical stability and their strong brightness make these constructs promising orange fluorescent biomarkers.


Asunto(s)
Cianobacterias/metabolismo , Proteínas Luminiscentes/metabolismo , Ficobilinas/metabolismo , Ficoeritrina/metabolismo , Urobilina/análogos & derivados , Cianobacterias/química , Proteínas Luminiscentes/química , Procesos Fotoquímicos , Ficobilinas/química , Ficoeritrina/química , Temperatura , Urobilina/química , Urobilina/metabolismo
14.
J Nat Med ; 78(1): 123-145, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37821666

RESUMEN

Hepatocellular carcinoma (HCC) treatment is a major challenge. Although andrographolide (Andro) has an anti-proliferation effect on HCC, its underlying mechanism is not yet elucidated, and whether Andro can inhibit HCC metastasis has not been reported. The present study aimed to clarify whether Andro inhibits SK-Hep-1 cell proliferation and HCC metastasis, and the mechanisms. The results showed that Andro significantly reduced the survival of HCC cells and tumor weight and volume in tumor-bearing nude mice. Andro also triggered apoptosis of HCC cells and upregulated MIR22HG, Cleaved Caspase 9/7/3 expression levels, and downregulated BCL-2 mRNA, BCL-2 expression levels. Knockdown of MIR22HG or overexpression of HuR attenuated the effects of Andro on the signal transduction of mitochondrial apoptotic pathway and proliferation ability in HCC cells. Moreover, Andro significantly reduced the invasive ability of the cells and the level of HCC cell lung metastasis, upregulated miR-22-3p expression level and downregulated HMGB1 and MMP-9 expression levels. MIR22HG or miR-22-3p knockdown attenuated the effects of Andro on the signaling of HMGB1/MMP-9 pathway and invasive ability in HCC cells, while the overexpression of HMGB1 attenuated the inhibitory effects of Andro on the MMP-9 expression level and invasive ability in HCC cells. Thus, the regulation of MIR22HG-HuR/BCL-2 and MIR22HG/HMGB1 signaling pathways is involved in the anti-HCC proliferation and metastasis effects of Andro. This study provided a new pharmacological basis for Andro in HCC treatment and, for the first time, identified a natural product molecule capable of positively regulating MIR22HG, which has a robust biological function.


Asunto(s)
Carcinoma Hepatocelular , Proteína HMGB1 , Neoplasias Hepáticas , MicroARNs , ARN Largo no Codificante , Animales , Ratones , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , ARN Largo no Codificante/genética , Proteína HMGB1/farmacología , Proteína HMGB1/uso terapéutico , Metaloproteinasa 9 de la Matriz/farmacología , Metaloproteinasa 9 de la Matriz/uso terapéutico , Ratones Desnudos , Línea Celular Tumoral , MicroARNs/genética , Proliferación Celular , Apoptosis , Proteínas Proto-Oncogénicas c-bcl-2 , Movimiento Celular
15.
Org Lett ; 26(2): 477-482, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38194611

RESUMEN

A palladium/norbornene catalyzed two-component coupling process involving acylation/cyanation of aryl iodides is reported. In this work, aryl acyl nitrile compounds are cleverly selected to provide both nitrile and acyl sources by palladium-catalyzed cleavage of the C-CN bond as both an electrophilic reagent and a termination reagent. This is the first example of C-CN bond cleavage bifunctionalization of aryl iodides. After a series of important NBE derivatives are screened, the products resulting from the bifunctionalization of aryl iodides are smoothly obtained. This strategy has a wide range of substrates and good functional group compatibility. Moreover, this synthetic protocol demonstrated a good application for the synthesis of diverse O,N,C-substituted isoindolinones.

16.
Zhonghua Yi Xue Za Zhi ; 93(27): 2152-4, 2013 Jul 16.
Artículo en Zh | MEDLINE | ID: mdl-24284249

RESUMEN

OBJECTIVE: To explore the effects of parecoxib sodium analgesia on serum concentrations of neuron-specific enolase (NSE) and S-100ß and postoperative cognitive function of elderly patients undergoing acute replacement of femoral head. METHODS: After the approval of institutional review board and the provision of informed consent, 80 patients over 70 years old, undergoing acute replacement of femoral head under combined spinal and epidural anesthesia and midazolam sedation at Qingdao Municipal Hospital and Qingdao Hiser Medical Center from January 2011 to May 2012, were randomly assigned into control group (group C, n = 40) and parecoxib group (group P, n = 40). In group P, parecoxib sodium 20/40 mg (based on weight 50 kg) was administered via an intravenous injection after admission with 12 hours intervals for six times. In group C, morphine 2/4 mg was given initially. Additional morphine 2 mg was given to maintain the pain visual analog scale (VAS) of 3 points or less in both groups. Primary observation indices: (1) postoperative time and additional amount of morphine; (2) rate of postoperative delirium (POD) and postoperative cognitive dysfunction (POCD) at 3 days, 1 week, 3 months and 6 months postoperation (T1-T4); (3) se rum levels of NSE and S-100ß were measured at the timepoints of before analgesia (t0), before anesthesia (t1), end of surgery (t2) and 6 hours, 24 hours, 48 hours postoperation (t3-t5); (4) other serious complications. RESULTS: Compared with group C, the additional amount of morphine, postoperative time, rate of POD and POCD at T1-T4, the level of NSE at t2-t5 and S-100ß at t1-t5 were lower in group P (P < 0.05). No other serious complications were observed. CONCLUSIONS: Parecoxib sodium analgesia reduces the rate of POD and POCD in elderly patients with neuroprotective effects.


Asunto(s)
Analgesia/métodos , Artroplastia de Reemplazo de Cadera/métodos , Isoxazoles/uso terapéutico , Fosfopiruvato Hidratasa/sangre , Anciano , Anciano de 80 o más Años , Femenino , Prótesis de Cadera , Humanos , Masculino , Manejo del Dolor , Periodo Posoperatorio , Subunidad beta de la Proteína de Unión al Calcio S100/sangre
17.
Curr Drug Targets ; 24(7): 568-583, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36999702

RESUMEN

To date, the incidence and mortality of chronic liver diseases such as cirrhosis and hepatocellular carcinoma due to the continued progression of hepatic fibrosis are increasing annually. Unfortunately, although a large number of studies have exhibited that some drugs have great potential for anti-fibrosis in animal and clinical trials, no specific anti-fibrosis drugs have been developed, and there is no better treatment for advanced cirrhosis than liver transplantation. It is a prevailing viewpoint that hepatic stellate cells (HSCs), as the mainstay of extracellular matrix secretion, are of great concern in the development of hepatic fibrosis. Therefore, targeting HSCs becomes extremely important to confront hepatic fibrosis. As previous studies described, inhibition of HSC activation and proliferation, induction of HSC death, and restoration of HSC quiescence are effective in reversing hepatic fibrosis. This review focuses on the current status of research on the treatment of hepatic fibrosis by inducing HSC death and elucidates the HSC death modes in detail and the crosstalk between them.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/patología , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Proliferación Celular
18.
J AOAC Int ; 106(5): 1295-1304, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37243686

RESUMEN

BACKGROUND: Platycladus orientalis leaves (POL), as the source of the traditional Chinese medicine (TCM) Platycladi Cacumen, has frequently been found to be misused with five adulterants including Chamaecyparis obtusa leaves (COL), Cupressus funebris leaves (CFL), Juniperus virginiana leaves (JVL), Sabina chinensis leaves (SCL), and Juniperus formosana leaves (JFL). OBJECTIVE: The purpose of this study was to distinguish POL (fresh leaves) from its five adulterants (fresh leaves). METHODS: The micromorphological features in terms of transection and microscopic characteristics of POL and adulterants were captured and compared using the an microscope. Both HPLC and TLC methods for the simultaneous determination of six bioactive flavonoids (myricitrin, isoquercitrin, quercitrin, amentoflavone, afzelin, and hinokiflavone) have been developed. RESULTS: There were significant differences in microscopic features of transverse section and powders. The TLC results suggested that the spots of myricitrin in POL were more obvious than those in the five adulterants. The contents of myricitrin and quercitrin, or the total content of flavonoids in POL, determined by HPLC, were significantly higher than those in the adulterants. CONCLUSION: POL was successfully distinguished from its five adulterants by the comparison of morphology, microscopic characteristics, and chemical profiles. HIGHLIGHTS: This research provides a comprehensive morphology, microscopic identification, TLC, and HPLC analysis for authenticating POL and its five adulterants.


Asunto(s)
Cupressaceae , Medicamentos Herbarios Chinos , Cromatografía Líquida de Alta Presión/métodos , Flavonoides/análisis , Cupressaceae/química , Medicamentos Herbarios Chinos/análisis , Medicina Tradicional China
19.
Chem Biol Interact ; 383: 110673, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37582412

RESUMEN

The induction of ferroptosis in hepatic stellate cells (HSCs) has shown promise in reversing liver fibrosis. And ferroptosis has been confirmed to be associated with glycolysis. The objective of this study is to determine whether ferroptosis inhibition in HSCs, induced by elevation of recombinant pyruvate dehydrogenase kinase isozyme 4 (PDK4)-mediated glycolysis, could mediate the pathogenesis of liver fibrosis. Liver fibrosis was induced using CCl4, the level of which was assessed through histochemical staining. Lentivirus was used to modulate the expression of specific genes. And underlying mechanisms were explored using primary HSCs extracted from normal mice. The results confirmed that Taurine up-regulated gene 1 (TUG1) expression was upregulated in liver fibrotic tissues and HSCs, showing a positive correlation with fibrosis. In addition, TUG1 attenuated ferroptosis in HSCs by promoting PDK4-mediated glycolysis, thereby promoting the progression of liver fibrosis. Moreover, TUG1 was observed to impact HSCs activation, exacerbating liver fibrosis to some extent. In conclusion, our study revealed that TUG1 expression was elevated in mouse models of liver fibrosis and activated HSCs, which inhibited ferroptosis in HSCs through PDK4-mediated glycolysis. This finding may open up a new therapeutic strategy for liver fibrosis.


Asunto(s)
Ferroptosis , Glucólisis , ARN Largo no Codificante , Animales , Ratones , Células Estrelladas Hepáticas/metabolismo , Isoenzimas/metabolismo , Hígado/metabolismo , Cirrosis Hepática/patología , ARN Largo no Codificante/metabolismo
20.
Zhonghua Xin Xue Guan Bing Za Zhi ; 40(10): 821-4, 2012 Oct.
Artículo en Zh | MEDLINE | ID: mdl-23302667

RESUMEN

OBJECTIVE: To determine the predictive value of HATCH score on recurrence of atrial fibrillation (AF) after radiofrequency catheter ablation (RFCA). METHODS: The data of 123 consecutive AF patients (74 paroxysmal and 49 persistent AF) who underwent RFCA between April 2009 and December 2010 in our department were retrospectively analyzed. Of theses patients, 65 (52.9%) patients had HATCH score = 0, 41 (33.3%) patients had HATCH score = 1, and 17 (13.8%) patients had HATCH score ≥ 2 (HATCH = 2 in 11 patients, HATCH = 3 in 5 patients, HATCH = 4 in 1 patient). The recurrence was defined as atrial tachyarrhythmia lasting more than 30 seconds after 3 months post RFCA. The patients were divided into recurrence group and no recurrence group. Relationship between HATCH score and recurrence was observed. RESULTS: There were 43 cases in recurrence group and 80 cases in no recurrence group. After 12 months follow-up, HATCH score was significant higher in recurrence group than in non-recurrence group [(0.91 ± 0.94) score vs. (0.53 ± 0.80) score, P < 0.05]. The ratio of patients with HATCH ≥ 2 in recurrence group was higher than in non-recurrence group [23.3% (10/43) vs. 8.8% (7/80), P < 0.01]. The sensitivity and specificity of HATCH ≥ 2 to define the risk of recurrence was 25.0%, 92.4% respectively. Cumulative non-recurrence rate of patients with HATCH score ≥ 2 was lower than patients with HATCH score = 0 and 1 (P < 0.05). CONCLUSION: Higher HATCH score is associated with increased risk of AF recurrence post RFCA.


Asunto(s)
Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , Anciano , Ablación por Catéter , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Recurrencia , Estudios Retrospectivos , Resultado del Tratamiento
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