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1.
Environ Geochem Health ; 46(4): 122, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483653

RESUMO

This study aims to explore the concentrations of Se and Hg in shellfish along the Gulf of Mannar (GoM) coast (Southeast India) and to estimate related risks and risk-based consumption limits for children, pregnant women, and adults. Se concentrations in shrimp, crab, and cephalopods ranged from 0.256 to 0.275 mg kg-1, 0.182 to 0.553 mg kg-1, and 0.176 to 0.255 mg kg-1, respectively, whereas Hg concentrations differed from 0.009 to 0.014 mg kg-1, 0.022 to 0.042 mg kg-1 and 0.011 to 0.024 mg kg-1, respectively. Se and Hg content in bamboo shark (C. griseum) was 0.242 mg kg-1 and 0.082 mg kg-1, respectively. The lowest and highest Se concentrations were found in C. indicus (0.176 mg kg-1) and C. natator (0.553 mg kg-1), while Hg was found high in C. griseum (0.082 mg kg-1) and low in P. vannamei (0.009 mg kg-1). Se shellfishes were found in the following order: crabs > shrimp > shark > cephalopods, while that of Hg were shark > crabs > cephalopods > shrimp. Se in shellfish was negatively correlated with trophic level (TL) and size (length and weight), whereas Hg was positively correlated with TL and size. Hg concentrations in shellfish were below the maximum residual limits (MRL) of 0.5 mg kg-1 for crustaceans and cephalopods set by FSSAI, 0.5 mg kg-1 for crustaceans and 1.0 mg kg-1 for cephalopods and sharks prescribed by the European Commission (EC/1881/2006). Se risk-benefit analysis, the AI (actual intake):RDI (recommended daily intake) ratio was > 100%, and the AI:UL (upper limit) ratio was < 100%, indicating that all shellfish have sufficient level of Se to meet daily requirements without exceeding the upper limit (UL). The target hazard quotient (THQ < 1) and hazard index (HI < 1) imply that the consumption of shellfish has no non-carcinogenic health impacts for all age groups. However, despite variations among the examined shellfish, it was consistently observed that they all exhibited a Se:Hg molar ratio > 1. This finding implies that the consumption of shellfish is generally safe in terms of Hg content. The health benefit indexes, Se-HBV and HBVse, consistently showed high positive values across all shellfish, further supporting the protective influence of Se against Hg toxicity and reinforcing the overall safety of shellfish consumption. Enhancing comprehension of food safety analysis, it is crucial to recognize that the elevated Se:Hg ratio in shellfish may be attributed to regular selenoprotein synthesis and the mitigation of Hg toxicity by substituting Se bound to Hg.


Assuntos
Mercúrio , Selênio , Poluentes Químicos da Água , Gravidez , Animais , Criança , Adulto , Feminino , Humanos , Mercúrio/análise , Selênio/análise , Monitoramento Biológico , Peixes/metabolismo , Frutos do Mar/análise , Crustáceos , Medição de Risco , Poluentes Químicos da Água/análise
2.
Trop Anim Health Prod ; 56(1): 31, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38172456

RESUMO

The present study was aimed to evaluate the influence of non-genetic factors on several first lactation and lifetime performance traits and elucidate their genetic parameters in an organized Vrindavani cattle population. Data on eight first-lactation and thirteen lifetime traits were collected on 2400 cows with pedigree records that were reared during 33-year period (1989-2021). The first-lactation traits included age at first calving (AFC), total milk yield (FTMY), standard milk yield (FSMY305), peak yield (FPY), lactation length (FLL), dry period (FDP), service period (FSP) and calving interval (FCI). Whereas, the lifetime traits mainly included total lifetime milk yield (TLMY), total standard milk yield (TSMY), number of lactations completed (NL), total lactation length (TLL), herd life (HL), productive life (PL), average milk yield per day of herd life (TLMY/HL), average milk yield per day of productive life (TLMY/PL), average milk yield per day of productive life (TLMY/TLL). Other lifetime production traits included average service period (ASP), average dry period (ADP), average calving interval (ACI) and unproductive days (UD). The heritability estimates of first-lactation traits ranged between 0.026 and 0.228 and were found to be low for AFC (0.180 ± 0.042), FCI (0.191 ± 0.125), FSMY305 (0.145 ± 0.061), FTMY (0.165 ± 0.048), FDP (0.052 ± 0.049) and FSP (0.026 ± 0.033); however, FLL (0.229 ± 0.044) and FPY (0.202 ± 0.046) showed moderate heritability. Positive phenotypic correlation (p < 0.001) was revealed among FTMY, TLMY, TLL, HL and PL. The AFC produced a significant effect (p < 0.05) on several traits i,e, TLL, TLMY/HL, FSMY305, FPY, TLMY, HL and TLMY/PL. Lower AFC was associated with higher TLMY, TLL and TLMY/HL; while FSMY305, FPY, HL and TLMY/PL were higher in heifers that calved late in their life. The results revealed that AFC may be optimized with first lactation and lifetime traits for this population.


Assuntos
Lactação , Leite , Bovinos/genética , Animais , Feminino , Lactação/genética , Fenótipo
3.
J Environ Manage ; 351: 119777, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38086119

RESUMO

Dual chambered microbial fuel cell (DMFC) is an advanced and effective treatment technology in wastewater treatment. The current work has made an effort to treat petrochemical industrial wastewater (PWW) as a DMFC substrate for power generation and organic substance removal. Investigating the impact of organic load (OL) on organic reduction and electricity generation is the main objective of this study. At the OL of 1.5 g COD/L, the highest total chemical oxygen demand (TCOD) removal efficiency of 88%, soluble oxygen demand (SCOD) removal efficiency of 80% and total suspended solids (TSS) removal efficiency of 71% were seen, respectively. In the same optimum condition of 1.5 g COD/L, the highest current and power density of about 270 mW/m2 and 376 mA/m2 were also observed. According to the results of this study, using high-strength organic wastewater in DMFC can assist in addressing the issue of the petrochemical industries and minimize the energy demand.


Assuntos
Fontes de Energia Bioelétrica , Purificação da Água , Águas Residuárias , Eletricidade , Purificação da Água/métodos , Análise da Demanda Biológica de Oxigênio , Eletrodos , Eliminação de Resíduos Líquidos/métodos
4.
Sci Rep ; 10(1): 10472, 2020 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-32591581

RESUMO

The development of metastases is the major cause of cancer related death. To develop a standardized method that define the ability of human cancer cells to degrade the basement membrane, e.g. the delamination capacity, is of importance to assess metastatic aggressiveness. We now present the in vivo CAM-Delam assay to visualize and quantify the ability of human cancer cells to delaminate and invade. The method includes seeding cancer cells on the chick chorioallantoic membrane (CAM), followed by the evaluation of cancer-induced delamination and potential invasion within hours to a few days. By testing a range of human cancer cell lines in the CAM-Delam assay, our results show that the delamination capacity can be divided into four categories and used to quantify metastatic aggressiveness. Our results emphasize the usefulness of this assay for quantifying delamination capacity as a measurement of metastatic aggressiveness, and in unraveling the molecular mechanisms that regulate delamination, invasion, formation of micro-metastases and modulations of the tumor microenvironment. This method will be useful in both the preclinical and clinical characterization of tumor biopsies, and in the validation of compounds that may improve survival in metastatic cancer.


Assuntos
Bioensaio/métodos , Membrana Corioalantoide/patologia , Neoplasias/patologia , Células A549 , Animais , Linhagem Celular Tumoral , Galinhas , Humanos , Células PC-3
5.
Differentiation ; 110: 8-16, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31539705

RESUMO

The terminal nerve ganglion (TNG) is a well-known structure of the peripheral nervous system in cartilaginous and teleost fishes. It derives from the olfactory placode during embryonic development. While the differentiation and migration of gonadotropin releasing hormone (GnRH)-expressing neurons from the olfactory placode has been well documented, the TNG has been neglected in birds and mammals, and its development is less well described. Here we describe the formation of a ganglion-like structure from migratory olfactory placodal cells in chicken. The TNG is surrounded by neural crest cells, but in contrast to other cranial sensory ganglia, we observed no neural crest corridor, and olfactory unsheathing cells appear only after the onset of neuronal migration. We identified Isl1 and Lhx2 as two transcription factors that label neuronal subpopulations in the forming TNG, distinct from GnRH1+ cells, thereby revealing a diversity of cell types during the formation of the TNG. We also provide evidence for extensive apoptosis in the terminal nerve ganglion shortly after its formation, but not in other cranial sensory ganglia. Moreover, at later stages placode-derived neurons expressing GnRH1, Isl1 and/or Lhx2 become incorporated in the telencephalon. The integration of TNG neurons into the telencephalon together with the earlier widespread apoptosis in the TNG might be an explanation why the TNG in mammals and birds is much smaller compared to other vertebrates.


Assuntos
Apoptose , Diferenciação Celular/fisiologia , Cistos Glanglionares/patologia , Neurogênese/fisiologia , Bulbo Olfatório/metabolismo , Animais , Apoptose/fisiologia , Biomarcadores/metabolismo , Movimento Celular/fisiologia , Galinhas , Hormônio Liberador de Gonadotropina/metabolismo
6.
Bioresour Technol ; 277: 62-67, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30658337

RESUMO

In this study, an attempt was made to enhance the biomethanation potential of seagrass (Syringodium isoetifolium) by the aid of disperser-tenside (polysorbate 80) disintegration for the first time in literature. A disperser rpm of 10,000 for 20 min and PS 80 dose of 0.000864 g/g TS were selected as ideal parameters for effectual seagrass biomass disintegration. Dispersion aided tenside disintegration (DTD) with a disperser energy consumption of 349 kJ/kg TS, was observed to be efficacious with a biomass lysis rate of 25.6%. The impact of DTD on bioacidification and biomethanation assay with respect to volatile fatty acids concentration (1100 mg/L) and methane generation (0.256 g/g COD), was greater than dispersion disintegration (DD) (800 mg/L; 0.198 g/g COD). Thus, S. isoetifolium is considered as a promising substrate to attain the third generation biofuel goals in the near future.


Assuntos
Alismatales/metabolismo , Metano/biossíntese , Tensoativos/farmacologia , Alismatales/efeitos dos fármacos , Biomassa , Ácidos Graxos Voláteis/biossíntese , Cinética
7.
Bioresour Technol ; 255: 116-122, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29414156

RESUMO

The present study aimed to increase the disintegration potential of marine macroalgae, (Ulva reticulata) through chemo mechanical pretreatment (CMP) in an energy efficient manner. By combining surfactant with disperser, the specific energy input was considerably reduced from 437.1 kJ/kg TS to 264.9 kJ/kg TS to achieve 10.7% liquefaction. A disperser rpm (10,000), pretreatment time (30 min) and tween 80 dosage (21.6 mg/L) were considered as an optimum for effective liquefaction of algal biomass. CMP was designated as an appropriate pretreatment resulting in a higher soluble organic release 1250 mg/L, respectively. Anaerobic fermentation results revealed that the volatile fatty acid (VFA) concentration was doubled (782 mg/L) in CMP when compared to mechanical pretreatment (MP) (345 mg/L). CMP pretreated algal biomass was considered as the suitable for biohydrogen production with highest H2 yield of about 63 mL H2/g COD than (MP) (45 mL H2/g COD) and control (10 mL H2/g COD).


Assuntos
Biocombustíveis , Ulva , Biomassa , Fermentação , Tensoativos
8.
Bioresour Technol ; 253: 256-261, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29353754

RESUMO

An exploration into the symbiotic impact of sonic-tenside (SDBS - sodium dodecyl benzene sulfonate) on biomass disintegration potential and to reduce the energy consumption was studied. At optimized condition (specific energy input 9600 kJ/kg TS; SDBS dosage 0.07 g/g SS), higher percentage of biomass lysis and solids reduction (23.9% and 19.8%) was obtained in blended sonic-tenside disintegration (STD), than sonic disintegration (SD) (17.6% and 9.8%). The bioacidogenic potential (BAP) assay in terms of volatile fatty acids (VFA) production (722 mg/L) was found to be higher for STD, in comparison to SD (350 mg/L). The impact of STD on anaerobic digestion was evident from its methane yield (0.239 g/g COD), higher than SD (0.182 g/g COD). A monetary evaluation of the present study provides a net gain of 2 USD/ton for STD, indicating the profitability of the technique.


Assuntos
Ácidos Graxos Voláteis , Metano , Anaerobiose , Biomassa , Cinética , Tensoativos
9.
Development ; 145(2)2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29352015

RESUMO

The transcription factor Sox2 is necessary to maintain pluripotency of embryonic stem cells, and to regulate neural development. Neurogenesis in the vertebrate olfactory epithelium persists from embryonic stages through adulthood. The role Sox2 plays for the development of the olfactory epithelium and neurogenesis within has, however, not been determined. Here, by analysing Sox2 conditional knockout mouse embryos and chick embryos deprived of Sox2 in the olfactory epithelium using CRISPR-Cas9, we show that Sox2 activity is crucial for the induction of the neural progenitor gene Hes5 and for subsequent differentiation of the neuronal lineage. Our results also suggest that Sox2 activity promotes the neurogenic domain in the nasal epithelium by restricting Bmp4 expression. The Sox2-deficient olfactory epithelium displays diminished cell cycle progression and proliferation, a dramatic increase in apoptosis and finally olfactory pit atrophy. Moreover, chromatin immunoprecipitation data show that Sox2 directly binds to the Hes5 promoter in both the PNS and CNS. Taken together, our results indicate that Sox2 is essential to establish, maintain and expand the neuronal progenitor pool by suppressing Bmp4 and upregulating Hes5 expression.


Assuntos
Proteínas Aviárias/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Neurogênese/fisiologia , Mucosa Olfatória/embriologia , Mucosa Olfatória/metabolismo , Proteínas Repressoras/genética , Fatores de Transcrição SOXB1/metabolismo , Animais , Apoptose , Proteínas Aviárias/deficiência , Proteínas Aviárias/genética , Sequência de Bases , Sítios de Ligação/genética , Proteína Morfogenética Óssea 4/metabolismo , Ciclo Celular , Linhagem da Célula , Proliferação de Células , Embrião de Galinha , Feminino , Técnicas de Inativação de Genes , Camundongos , Camundongos Knockout , Neurogênese/genética , Gravidez , Regiões Promotoras Genéticas , Fatores de Transcrição SOXB1/deficiência , Fatores de Transcrição SOXB1/genética , Regulação para Cima
10.
3 Biotech ; 7(4): 248, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28711983

RESUMO

Xanthan gum (XG) production by Xanthomonas campestris NCIM 2961 using jackfruit seed powder (JSP) as a novel substrate was reported. Central composite design (CCD) of response surface method (RSM) was used to evaluate the linear and interaction effects of five medium variables (JSP, peptone, citric acid, K2HPO4 and KH2PO4) for XG production. Maximum XG production (51.62 g/L) was observed at the optimum level of JSP (4 g/L), peptone (0.93 g/L), citric acid (0.26 g/L), K2HPO4 (1.29 g/L) and KH2PO4 (0.5 g/L). K2HPO4 and KH2PO4 were found as significant medium components, which served as buffering agents as well as nutrients for X. campestris growth. The obtained biopolymer was characterized as XG by XRD and FTIR analysis. Results of this study revealed that JSP was found to be a suitable low cost substrate for XG production.

11.
Bioresour Technol ; 241: 710-719, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28622653

RESUMO

The objective of this study was to evaluate the effect of dioctyl sodium sulphosuccinate (DOSS, a surfactant) on lysis rate of sludge and specific energy required for sonic pretreatment of waste activated sludge (WAS). Different ultrasonic power levels, WAS concentrations, DOSS dosages, and specific energy levels were used to compare pretreatment efficiencies. At an optimum time of 10min with ultrasonic power level of 160W, DOSS coupled sonic pretreatment resulted in better lysis rate (24.7%) of sludge than sonic pretreatment (17.6%). Biodegradability estimation through non-linear regression modeling revealed that DOSS coupled ultrasound pretreatment of sludge showed better biodegradability with higher hydrolysis constant (about 0.25d-1) than sonic pretreatment (0.19d-1). Nearly six times less energy was required for DOSS coupled ultrasound pretreatment compared to that required for sonic pretreatment. Therefore, DOSS coupled ultrasound pretreatment makes the pretreatment process energetically positive.


Assuntos
Biocombustíveis , Esgotos , Anaerobiose , Biodegradação Ambiental , Hidrólise , Tensoativos , Eliminação de Resíduos Líquidos
12.
Bioresour Technol ; 228: 156-163, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28064132

RESUMO

In this study, an effort has been made to reduce the energy cost of liquefaction by coupling a mechanical disperser with a chemical (sodium tripolyphosphate). In terms of the cost and specific energy demand of liquefaction, the algal biomass disintegrated at 12,000rpm for 30min, and an STPP dosage of about 0.04g/gCOD was chosen as an optimal parameter. Chemo disperser liquefaction (CDL) was found to be energetically and economically sustainable in terms of liquefaction, methane production, and net profit (15%, 0.14gCOD/gCOD, and 4 USD/Ton of algal biomass) and preferable to disperser liquefaction (DL) (10%, 0.11 gCOD/gCOD, and -475 USD/Ton of algal biomass).


Assuntos
Biomassa , Biotecnologia/métodos , Metano/biossíntese , Ácidos/química , Anaerobiose , Análise de Variância , Biodegradação Ambiental , Biopolímeros/análise , Biotecnologia/economia , Custos e Análise de Custo , Hidrólise , Modelos Lineares , Dinâmica não Linear , Compostos Orgânicos/análise , Alga Marinha/metabolismo
13.
J Environ Manage ; 180: 351-8, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27254294

RESUMO

Tubular upflow microbial fuel cell (MFC) utilizing sea food processing wastewater was evaluated for wastewater treatment efficiency and power generation. At an organic loading rate (OLR) of 0.6 g d(-1), the MFC accomplished total and soluble chemical oxygen demand (COD) removal of 83 and 95%, respectively. A maximum power density of 105 mW m(-2) (2.21 W m(-3)) was achieved at an OLR of 2.57 g d(-1). The predominant bacterial communities of anode biofilm were identified as RB1A (LC035455), RB1B (LC035456), RB1C (LC035457) and RB1E (LC035458). All the four strains belonged to genera Stenotrophomonas. The results of the study reaffirms that the seafood processing wastewater can be treated in an upflow MFC for simultaneous power generation and wastewater treatment.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Biofilmes , Stenotrophomonas/metabolismo , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/microbiologia , Purificação da Água/métodos , Análise da Demanda Biológica de Oxigênio , Eletricidade , Eletrodos , Alimentos Marinhos , Stenotrophomonas/classificação , Águas Residuárias/análise
14.
Trop Biomed ; 31(3): 414-21, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25382467

RESUMO

The ectoparasitic tick, Rhipicephalus (Boophilus) microplus collected at various cattle farms in and around Chennai was subjected to treatment of different crude solvent extracts of leaves of Ocimum basilicum and Spilanthes acmella for acaricidal activity. Among various solvent extracts of leaves of O. basilicum and S. acmella used, chloroform extract of O. basilicum at concentrations between 6% and 10% exhibited 70% and 100% mortality of ticks when compared to control. The LC50 and LC90 values of the chloroform extract of leaves of O. basilicum treatment on the ticks after 24 h were observed as 5.46% and 7.69%. Quantitative and qualitative analysis of α- and ß- carboxylesterase enzymes in the whole gut homogenate of cattle tick, R. microplus treated with chloroform extract of leaves of O. basilicum revealed higher level of activities for the enzymes. This indicated that there was an induced response in the tick, R. microplus against the toxic effects of the extract of O. basilicum.


Assuntos
Acaricidas/farmacologia , Asteraceae/química , Ocimum basilicum/química , Extratos Vegetais/farmacologia , Rhipicephalus/efeitos dos fármacos , Acaricidas/isolamento & purificação , Animais , Bioensaio , Carboxilesterase/análise , Trato Gastrointestinal/enzimologia , Índia , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Rhipicephalus/enzimologia , Análise de Sobrevida
15.
Cell Death Dis ; 3: e354, 2012 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-22825472

RESUMO

According to the concept of lipotoxicity, ectopic accumulation of lipids in non-adipose tissue induces pathological changes. The most prominent effects are seen in fatty liver disease, lipid cardiomyopathy, non-insulin-dependent diabetes mellitus, insulin resistance and skeletal muscle myopathy. We used the MCK(m)-hLPL mouse distinguished by skeletal and cardiac muscle-specific human lipoprotein lipase (hLPL) overexpression to investigate effects of lipid overload in skeletal muscle. We were intrigued to find that ectopic lipid accumulation induced proteasomal activity, apoptosis and skeletal muscle damage. In line with these findings we observed reduced Musculus gastrocnemius and Musculus quadriceps mass in transgenic animals, accompanied by severely impaired physical endurance. We suggest that muscle loss was aggravated by impaired muscle regeneration as evidenced by reduced cross-sectional area of regenerating myofibers after cardiotoxin-induced injury in MCK(m)-hLPL mice. Similarly, an almost complete loss of myogenic potential was observed in C2C12 murine myoblasts upon overexpression of LPL. Our findings directly link lipid overload to muscle damage, impaired regeneration and loss of performance. These findings support the concept of lipotoxicity and are a further step to explain pathological effects seen in muscle of obese patients, patients with the metabolic syndrome and patients with cancer-associated cachexia.


Assuntos
Ácidos Graxos/metabolismo , Lipase Lipoproteica/metabolismo , Músculo Esquelético/metabolismo , Animais , Apoptose , Linhagem Celular , Creatina Quinase/genética , Creatina Quinase/metabolismo , Humanos , Lipase Lipoproteica/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mioblastos/metabolismo , Regeneração , Triglicerídeos/metabolismo
16.
FEBS Lett ; 584(15): 3415-23, 2010 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-20600009

RESUMO

Angiogenesis is a physiological process involving the growth of blood vessel in response to specific stimuli. The present study shows that limited microgravity treatments induce angiogenesis by activating macrovascular endothelial cells. Inhibition of nitric oxide production using pharmacological inhibitors and inducible nitric oxide synthase (iNOS) small interfering ribo nucleic acid (siRNA) abrogated microgravity induced nitric oxide production in macrovascular cells. The study further delineates that iNOS acts as a molecular switch for the heterogeneous effects of microgravity on macrovascular, endocardial and microvascular endothelial cells. Further dissection of nitric oxide downstream signaling confirms that simulated microgravity induces angiogenesis via the cyclic guanosine monophosphate (cGMP)-PKG dependent pathway.


Assuntos
Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Células Endoteliais/enzimologia , Neovascularização Fisiológica , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Simulação de Ausência de Peso , Animais , Bovinos , Movimento Celular , Proliferação de Células , Galinhas , Células Endoteliais/citologia , Humanos , Óxido Nítrico Sintase Tipo III/metabolismo , Transdução de Sinais , Sus scrofa , Ausência de Peso , Cicatrização
17.
Br J Pharmacol ; 158(7): 1720-34, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19912234

RESUMO

BACKGROUND AND PURPOSE: Nitric oxide (NO) promotes angiogenesis by activating endothelial cells. Thalidomide arrests angiogenesis by interacting with the NO pathway, but its putative targets are not known. Here, we have attempted to identify these targets. EXPERIMENTAL APPROACH: Cell-based angiogenesis assays (wound healing of monolayers and tube formation in ECV304, EAhy926 and bovine arterial endothelial cells), along with ex vivo and in vivo angiogenesis assays, were used to explore interactions between thalidomide and NO. We also carried out in silico homology modelling and docking studies to elucidate possible molecular interactions of thalidomide and soluble guanylyl cyclase (sGC). KEY RESULTS: Thalidomide inhibited pro-angiogenic functions in endothelial cell cultures, whereas 8-bromo-cGMP, sildenafil (a phosphodiesterase inhibitor) or a NO donor [sodium nitroprusside (SNP)] increased these functions. The inhibitory effects of thalidomide were reversed by adding 8-bromo-cGMP or sildenafil, but not by SNP. Immunoassays showed a concentration-dependent decrease of cGMP in endothelial cells with thalidomide, without affecting the expression level of sGC protein. These results suggested that thalidomide inhibited the activity of sGC. Molecular modelling and docking experiments revealed that thalidomide could interact with the catalytic domain of sGC, which would explain the inhibitory effects of thalidomide on NO-dependent angiogenesis. CONCLUSION AND IMPLICATIONS: Our results showed that thalidomide interacted with sGC, suppressing cGMP levels in endothelial cells, thus exerting its anti-angiogenic effects. These results could lead to the formulation of thalidomide-based drugs to curb angiogenesis by targeting sGC.


Assuntos
Inibidores da Angiogênese/farmacologia , Guanilato Ciclase/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Óxido Nítrico/metabolismo , Receptores Citoplasmáticos e Nucleares/efeitos dos fármacos , Talidomida/farmacologia , Inibidores da Angiogênese/administração & dosagem , Animais , Domínio Catalítico/efeitos dos fármacos , Bovinos , Células Cultivadas , GMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Guanilato Ciclase/metabolismo , Humanos , Masculino , Modelos Moleculares , Ratos , Ratos Wistar , Receptores Citoplasmáticos e Nucleares/metabolismo , Guanilil Ciclase Solúvel , Talidomida/administração & dosagem , Veias Umbilicais , Cicatrização/efeitos dos fármacos
18.
Biochem Cell Biol ; 86(1): 1-10, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18364740

RESUMO

Cadmium (Cd) perturbs vascular health and interferes with endothelial function. However, the effects of exposing endothelial cells to low doses of Cd on the production of nitric oxide (NO) are largely unknown. The objective of the present study was to evaluate these effects by using low levels of CdCl2 concentrations, ranging from 10 to 1000 nmol/L. Cd perturbations in endothelial function were studied by employing wound-healing and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays. The results suggest that a CdCl2 concentration of 100 nmol/L maximally attenuated NO production, cellular migration, and energy metabolism in endothelial cells. An egg yolk angiogenesis model was employed to study the effect of Cd exposure on angiogenesis. The results demonstrate that NO supplementation restored Cd-attenuated angiogenesis. Immunofluorescence, Western blot, and immuno-detection studies showed that low levels of Cd inhibit NO production in endothelial cells by blocking eNOS phosphorylation, which is possibly linked to processes involving endothelial function and dysfunction, including angiogenesis.


Assuntos
Cloreto de Cádmio/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Gema de Ovo/citologia , Gema de Ovo/fisiologia , Células Endoteliais/efeitos dos fármacos , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Neovascularização Fisiológica/efeitos dos fármacos , Fosforilação , Succinato Desidrogenase/antagonistas & inibidores , Succinato Desidrogenase/metabolismo
19.
Eur J Cell Biol ; 87(3): 147-61, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18023499

RESUMO

Leakiness of the endothelial bed is attributed to the over-perfusion of the pulmonary bed, which leads to high altitude pulmonary edema (HAPE). Inhalation of nitric oxide has been successfully employed to treat HAPE patients. We hypothesize that nitric oxide intervenes in the permeability of the pulmonary macrovascular endothelial bed to rectify the leaky bed under hypoxia. Our present work explores the underlying mechanism of 'hypoxia-mediated' endothelial malfunction by using human umbilical cord-derived immortalized endothelial cells, ECV-304, and bovine pulmonary artery primary endothelial cells. The leakiness of the endothelial monolayer was increased by two-fold under hypoxia in comparison to cells under normoxia, while optical tweezers-based tethering assays reported a higher membrane tension of endothelial cells under hypoxia. Phalloidin staining demonstrated depolymerization of F-actin stress fibers and highly polarized F-actin patterns in endothelial cells under hypoxia. Nitric oxide, 8-Br-cGMP and sildenafil citrate (phosphodiesterase type 5 inhibitor) led to recovery from hypoxia-induced leakiness of the endothelial monolayers. Results of the present study also suggest that 'hypoxia-induced' cytoskeletal rearrangements and membrane leakiness are associated with the low nitric oxide availability under hypoxia. We conclude that nitric oxide-based recovery of hypoxia-induced leakiness of endothelial cells is a cyclic guanosine monophosphate (cGMP)-dependent phenomenon.


Assuntos
Actinas/metabolismo , Hipóxia Celular , GMP Cíclico/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Óxido Nítrico/metabolismo , Animais , Permeabilidade Capilar/fisiologia , Bovinos , Linhagem Celular , Células Cultivadas , Células Endoteliais/citologia , Endotélio Vascular/citologia , Humanos
20.
Biochem Cell Biol ; 85(6): 709-20, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18059529

RESUMO

Hepatic stellate cells are liver-specific pericytes and exist in close proximity with endothelial cells. The activation of liver pericytes is intrinsic to liver pathogenesis, and leads to endothelial dysfunction, including the low bioavailability of nitric oxide (NO). However, the role of nitric oxide in pericyte-endothelium cross-talk has not yet been elucidated. This work examines the cellular mechanism of action of NO in pericyte-mediated endothelial dysfunction. We used in vitro coculture and conditioned medium systems to study the effects of activated liver pericytes on endothelial function, and an egg yolk vascular bed model was used to study the effects of activated pericytes on angiogenesis. This study also demonstrates that activated pericytes attenuate the migration, proliferation, permeability, and NO production of endothelial cells. Our results demonstrate that activated pericytes restrict angiogenesis in egg yolk vascular bed models, and NO supplementation recovers 70% of the inhibition. Our results also demonstrate that supplementation with NO, sildenafil citrate (phosphodiesterase inhibitor), and 8-bromo-cGMP (cGMP analog) partially recovers activated-pericyte-mediated endothelium dysfunction. We conclude that NO-cGMP alleviates activated-pericyte-associated endothelial dysfunction, including angiogenesis, in a cGMP-dependent manner.


Assuntos
GMP Cíclico/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Óxido Nítrico/metabolismo , Pericitos/metabolismo , Animais , Linhagem Celular , Permeabilidade da Membrana Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Extensões da Superfície Celular/efeitos dos fármacos , Galinhas , Meios de Cultivo Condicionados/farmacologia , Relação Dose-Resposta a Droga , Células Endoteliais/citologia , Células Endoteliais/ultraestrutura , Inibidores Enzimáticos/farmacologia , Guanilato Ciclase/antagonistas & inibidores , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/enzimologia , Hepatócitos/ultraestrutura , Humanos , Hidrólise/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Óxido Nítrico/biossíntese , Pericitos/citologia , Pericitos/efeitos dos fármacos , Pericitos/ultraestrutura , Solubilidade/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
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