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1.
Nitric Oxide ; 148: 1-12, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38636582

RESUMO

Epidemiological studies show a strong correlation between diabetes and the increased risk of developing different cancers, including melanoma. In the present study, we investigated the impact of a streptozotocin (STZ)-induced hyperglycemic environment on B16F10-Nex2 murine melanoma development. Hyperglycemic male C57Bl/6 mice showed increased subcutaneous tumor development, partially inhibited by metformin. Tumors showed increased infiltrating macrophages, and augmented IL-10 and nitric oxide (NO) concentrations. In vivo neutralization of IL-10, NO synthase inhibition, and depletion of macrophages reduced tumor development. STZ-treated TLR4 KO animals showed delayed tumor development; the transfer of hyperglycemic C57Bl/6 macrophages to TLR4 KO reversed this effect. Increased concentrations of IL-10 present in tumor homogenates of hyperglycemic mice induced a higher number of pre-angiogenic structures in vitro, and B16F10-Nex2 cells incubated with different glucose concentrations in vitro produced increased levels of IL-10. In summary, our findings show that a hyperglycemic environment stimulates murine melanoma B16F10-Nex2 primary tumor growth, and this effect is dependent on tumor cell stimulation, increased numbers of macrophages, and augmented IL-10 and NO concentrations. These findings show the involvement of tumor cells and other components of the tumor microenvironment in the development of subcutaneous melanoma under hyperglycemic conditions, defining novel targets for melanoma control in diabetic patients.


Assuntos
Hiperglicemia , Interleucina-10 , Macrófagos , Melanoma Experimental , Camundongos Endogâmicos C57BL , Óxido Nítrico , Animais , Interleucina-10/metabolismo , Óxido Nítrico/metabolismo , Masculino , Hiperglicemia/metabolismo , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Knockout , Linhagem Celular Tumoral
2.
J Dairy Sci ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38908714

RESUMO

The rumen microbiome is crucial for converting feed into absorbable nutrients used for milk synthesis, and the efficiency of this process directly impacts the profitability and sustainability of the dairy industry. Recent studies have found that the rumen microbial composition explains part of the variation in feed efficiency traits, including dry matter intake, milk energy, and residual feed intake. The main goal of this study was to reveal relationships between the host genome, rumen microbiome, and dairy cow feed efficiency using structural equation models. Our specific objectives were to (i) infer the mediation effects of the rumen microbiome on feed efficiency traits, (ii) estimate the direct and total heritability of feed efficiency traits, and (iii) calculate the direct and total breeding values of feed efficiency traits. Data consisted of dry matter intake, milk energy, and residual feed intake records, SNP genotype data, and 16S rRNA rumen microbial abundances from 448 mid-lactation Holstein cows from 2 research farms. We implemented structural equation models such that the host genome directly affects the phenotype (GP → P) and the rumen microbiome (GM → P), while the microbiome affects the phenotype (M → P), partially mediating the effect of the host genome on the phenotype (G → M → P). We found that 7 to 30% of microbes within the rumen microbial community had structural coefficients different from zero. We classified these microbes into 3 groups that could have different uses in dairy farming. Microbes with heritability <0.10 but significant causal effects on feed efficiency are attractive for external interventions. On the other hand, 2 groups of microbes with heritability ≥0.10, significant causal effects, and genetic covariances and causal effects with the same or opposite sign to feed efficiency are attractive for selective breeding, improving or decreasing the trait heritability and response to selection, respectively. In general, the inclusion of the different microbes in genomic models tends to decrease the trait heritability rather than increase it, ranging from -15% to +5%, depending on the microbial group and phenotypic trait. Our findings provide more understanding to target rumen microbes that can be manipulated, either through selection or management interventions, to improve feed efficiency traits.

3.
J Dairy Sci ; 107(5): 3090-3103, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38135048

RESUMO

It is now widely accepted that dairy cow performance is influenced by both the host genome and rumen microbiome composition. The contributions of the genome and the microbiome to the phenotypes of interest are quantified by heritability (h2) and microbiability (m2), respectively. However, if the genome and microbiome are included in the model, then the h2 reflects only the contribution of the direct genetic effects quantified as direct heritability (hd2), and the holobiont effect reflects the joint action of the genome and the microbiome, quantified as the holobiability (ho2). The objectives of this study were to estimate h2, hd2,m2, and ho2 for dry matter intake, milk energy, and residual feed intake; and to evaluate the predictive ability of different models, including genome, microbiome, and their interaction. Data consisted of feed efficiency records, SNP genotype data, and 16S rRNA rumen microbial abundances from 448 mid-lactation Holstein cows from 2 research farms. Three kernel models were fit to each trait: one with only the genomic effect (model G), one with the genomic and microbiome effects (model GM), and one with the genomic, microbiome, and interaction effects (model GMO). The model GMO, or holobiont model, showed the best goodness-of-fit. The hd2 estimates were always 10% to 15% lower than h2 estimates for all traits, suggesting a mediated genetic effect through the rumen microbiome, and m2 estimates were moderate for all traits, and up to 26% for milk energy. The ho2 was greater than the sum of hd2 and m2, suggesting that the genome-by-microbiome interaction had a sizable effect on feed efficiency. Kernel models fitting the rumen microbiome (i.e., models GM and GMO) showed larger predictive correlations and smaller prediction bias than the model G. These findings reveal a moderate contribution of the rumen microbiome to feed efficiency traits in lactating Holstein cows and strongly suggest that the rumen microbiome mediates part of the host genetic effect.


Assuntos
Lactação , Microbiota , Feminino , Bovinos , Animais , Rúmen , RNA Ribossômico 16S , Leite , Fenótipo , Ração Animal , Dieta/veterinária
4.
Nitric Oxide ; 132: 15-26, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36736618

RESUMO

Spatial confinement and temporal regulation of signaling by nitric oxide (NO) and reactive oxygen species (ROS) occurs in cancer cells. Signaling mediated by NO and ROS was investigated in two sub clones of the murine melanoma B16F10-Nex2 cell line, Nex10C and Nex8H treated or not with bradykinin (BK). The sub clone Nex10C, similar to primary site cells, has a low capacity for colonizing the lungs, whereas the sub clone Nex8H, similar to metastatic cells, corresponds to a highly invasive melanoma. BK-treated Nex10C cells exhibited a transient increase in NO and an inhibition in basal O2- levels. Inhibition of endogenous NO production by l-NAME resulted in detectable levels of O2-. l-NAME promoted Rac1 activation and enhanced Rac1-PI3K association. l-NAME in the absence of BK resulted in Nex10C cell migration and invasion, suggesting that NO is a negative regulator of O2- mediated cell migration and cell invasion. BK-treated Nex8H cells sustained endogenous NO production through the activation of NOS3. NO activated Rac1 and promoted Rac1-PI3K association. NO stimulated cell migration and cell invasion through a signaling axis involving Ras, Rac1 and PI3K. In conclusion, a role for O2- and NO as positive regulators of Rac1-PI3K signaling associated with cell migration and cell invasion is proposed respectively for Nex10C and Nex8H murine melanoma cells.


Assuntos
Bradicinina , Melanoma , Camundongos , Animais , Bradicinina/farmacologia , Bradicinina/metabolismo , Superóxidos , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Movimento Celular
5.
Cell Biol Int ; 46(1): 158-169, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34719858

RESUMO

Low levels of nitric oxide (NO) produced by constitutively expressed inducible NO synthase (NOS2) in tumor cells may be an important factor in their development. NOS2 expression is associated with high mortality rates for various cancers. Alternative splicing of NOS2 down-regulates its enzymatic activity, resulting in decreased intracellular NO concentrations. Specific probes to detect alternative splicing of NOS2 were used in two isogenic human colon cancer cell lines derived either from the primary tumor (SW480) or from a lymph node metastasis (SW620). Splicing variant of NOS2 S3, lacking exons 9, 10, and 11, was overexpressed in SW480 cells. NOS2 S3 was silenced in SW480 cells. Flow-cytometry analysis was used to estimate the intracellular NO levels and to analyze the cell cycle of the studied cell lines. Western blot analysis and quantitative real-time polymerase chain reaction (qRT-PCR) were used to determine apoptosis and autophagy markers. SW480 and SW620 cells expressed NOS2 S3. Overexpression of the NOS2 S3 in SW480 cells downregulated intracellular NO levels. SW480 cells with knocked down NOS2 S3 (referred to as S3C9 cells) had higher intracellular levels of NO compared to the wild-type SW480 cells under serum restriction. Higher NO levels resulted in the loss of viability of S3C9 cells, which was associated with autophagy. Induction of autophagy by elevated intracellular NO levels in S3C9 cells under serum restriction, suggests that autophagy operates as a cytotoxic response to nitrosative stress. The expression of NOS2 S3 plays an important role in regulating intracellular NO production and maintaining viability in SW480 cells under serum restriction. These findings may prove significant in the design of NOS2/NO-based therapies for colon cancer.


Assuntos
Adenocarcinoma/enzimologia , Autofagia , Neoplasias do Colo/enzimologia , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/metabolismo , Estresse Nitrosativo , Adenocarcinoma/genética , Adenocarcinoma/secundário , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Óxido Nítrico Sintase Tipo II/genética , Isoformas de Proteínas , Transdução de Sinais
6.
Phys Chem Chem Phys ; 25(1): 439-454, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36477262

RESUMO

The choline chloride-urea binary mixture in the molar ratio (1 : 2), commonly known as reline, is an archetypal solvent among deep eutectic solvents (DES). Neutron diffraction (ND) and empirical potential structure refinement (EPSR) results provided evidence that reline exhibits a peculiar structural transformation upon water addition that manifests in a sudden dewetting of the choline cations at ∼51 wt% water and, therefore, a non-monotonic variation of the choline-water and choline-choline coordination. Here, we study, through molecular dynamics (MD), the influence of water on the structure of a choline chloride : urea : water DES (1 : 2 : ζ; ζ = 0 to 40), to gain additional insight into the molecular source of this peculiar structural transformation. Five different force fields were investigated. Our results show that the ND/EPSR non-monotonic behavior of the choline-choline coordination is qualitatively reproduced by those force fields that describe more accurately the dynamics of the DES, namely, the diffusion and viscosity coefficients. However, the apparent increase of the choline-choline coordination at ζ > 10 (41 wt%) is associated with the drain of a particular first coordination sphere, rather than with a dewetting of the choline cations, as predicted by ND/EPSR. Thus, a monotonic increase of the choline-water coordination is found instead, as well as the emergence of a tetrahedral hydrogen bond network of water, opposite to ND/EPSR. The highest rate of depletion upon initial hydration is found for urea around choline (∼0.9 urea molecules/ζ), whereas choline depicts the highest rate of hydration (∼2.5 water molecules/ζ). These rates decrease with ζ and a structural transition that stabilizes above 41 wt% is observed, consistent with ND/EPSR results. Despite limitations in the force fields, we argue that the experimental and simulation opposite pictures could be related to an underestimation of water's hydrogen bond network portrayed by the EPSR method. Overall, a smoother transition from a DES to an aqueous solution of the DES components is portrayed by MD, compared with ND/EPSR.


Assuntos
Colina , Água , Água/química , Colina/química , Ureia/química , Solventes/química , Cátions
7.
BMC Public Health ; 22(1): 2341, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36517802

RESUMO

BACKGROUND: Lifestyle factors are widely recognized as modifiers and major risk factors for non-communicable diseases. Previous studies on the prevalence of multimorbidity in Portugal predict an unfavourable reality. The aim of the present study was to analyse 1) the prevalence of multimorbidity in Portugal and 2) the association of individuals' lifestyles and sociodemographic factors with multimorbidity. METHODS: A cross-sectional, population-wide study was conducted on a representative sample of the general population of Portuguese adults aged ≥ 20 years. Categorical variables were described by their respective absolute and relative frequencies (n (%)). All variables with a p-value < 20% were included in the multiple logistic regression model. The variables were removed one by one in descending order of p-value (p) until the model contained only significant variables. The results are presented using the odds ratio and 95% confidence intervals. P-values ​​ < 5% were considered significant. RESULTS: The prevalence of multimorbidity was 48.9% (n = 436), and the odds of multimorbidity increased 4% (p < 0.001) for each year of increase in age. Participants with reasonable general health status had higher odds of multimorbidity (Odds ratio (OR) = 3.04; p < 0.001), and those with poor or very poor general health status had even higher odds (OR = 9.14; p < 0.001). Compared to those who never smoked, participants who quit smoking ≥ 1 year presented an increase of 91% (p = 0.005) in the odds of multimorbidity. Individuals with no good-quality sleep, non-moderate screen time, or non-moderate stress level had higher odds of multimorbidity (OR = 1.98; OR = 1.88; OR = 2.22, respectively. p < 0.001). CONCLUSIONS: This study presented a new approach to multimorbidity in Portugal. Population-based, multidimensional lifestyle interventions are needed. It seems necessary to optimize and adjust measures to prevent non-communicable diseases to improve health in Portugal. In the future, longitudinal studies will be an asset to reinforce and clarify these conclusions.


Assuntos
Multimorbidade , Doenças não Transmissíveis , Adulto , Humanos , Estudos Transversais , Portugal/epidemiologia , Doenças não Transmissíveis/epidemiologia , Fatores Sociodemográficos , Estilo de Vida , Prevalência
8.
Nitric Oxide ; 93: 78-89, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31539562

RESUMO

Human immunodeficiency virus (HIV) infections are typically accompanied by high levels of secreted inflammatory cytokines and generation of high levels of reactive oxygen species (ROS). To elucidate how HIV-1 alters the cellular redox environment during viral replication, we used human HIV-1 infected CD4+T lymphocytes and uninfected cells as controls. ROS and nitric oxide (NO) generation, antioxidant enzyme activity, protein phosphorylation, and viral and proviral loads were measured at different times (2-36 h post-infection) in the presence and absence of the NO donor S-nitroso-N-acetylpenicillamine (SNAP). HIV-1 infection increased ROS generation and decreased intracellular NO content. Upon infection, we observed increases in copper/zinc superoxide dismutase (SOD1) and glutathione peroxidase (GPx) activities, and a marked decrease in glutathione (GSH) concentration. Exposure of HIV-1 infected CD4+T lymphocytes to SNAP resulted in an increasingly oxidizing intracellular environment, associated with tyrosine nitration and SOD1 inhibition. In addition, SNAP treatment promoted phosphorylation and activation of the host's signaling proteins, PKC, Src kinase and Akt. Inhibition of PKC leads to inhibition of Src kinase strongly suggesting that PKC is the upstream element in this signaling cascade. Changes in the intracellular redox environment after SNAP treatment had an effect on HIV-1 replication as reflected by increases in proviral and viral loads. In the absence or presence of SNAP, we observed a decrease in viral load in infected CD4+T lymphocytes pre-incubated with the PKC inhibitor GF109203X. In conclusion, oxidative/nitrosative stress conditions derived from exposure of HIV-1-infected CD4+T lymphocytes to an exogenous NO source trigger a signaling cascade involving PKC, Src kinase and Akt. Activation of this signaling cascade appears to be critical to the establishment of HIV-1 infection.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , HIV-1/metabolismo , Óxido Nítrico/metabolismo , Transdução de Sinais/fisiologia , Replicação Viral/fisiologia , Infecções por HIV , Humanos , Doadores de Óxido Nítrico/farmacologia , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , S-Nitroso-N-Acetilpenicilamina/farmacologia , Quinases da Família src/metabolismo
9.
Nitric Oxide ; 89: 1-13, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31009708

RESUMO

Cancer development is closely related to chronic inflammation, which is associated with identifiable markers of tumor progression, such as uncontrolled cell proliferation, angiogenesis, genomic instability, chemotherapeutic resistance, and metastases. Redox processes mediated by reactive oxygen species (ROS) and nitric oxide (NO) within the inflammatory tumor microenvironment play an essential role in directly influencing intercellular and intracellular signaling. These reactive species originating in the cancer cell or its microenvironment, mediate the epithelial-mesenchymal transition (EMT) and the mesenchymal-epithelial transition (MET). However, intracellular interactions between NO and ROS must be controlled to prevent cell death. Melanoma, breast, and colon cancer cells have developed a mechanism to survive and adapt to oxidative and nitrosative stress. The mechanism involves a spatial-temporal fine adjustment of the intracellular concentrations of NO and ROS, thereby guaranteeing the successful development of cancer cells. Physiological concentrations of NO and supra physiological concentrations of ROS are prevalent in cancer cells at the primary site. The situation reverses in cancer cells undergoing the EMT prior to being released into the blood stream. Intracellular supra physiological concentrations of NO found in circulating cancer cells endow them with anoikis resistance. When the anoikis-resistant cancer cells arrive at a metastatic site they undergo the MET. Endogenous supra physiological concentrations of ROS and physiological NO concentrations are prevalent in these cells. Understanding tumor progression from the perspective of redox signaling permits the characterization of new markers and approaches to therapy. The synthesis and use of compounds with the capacity of modifying intracellular concentrations of NO and ROS may prove effective in disrupting a redox homeostasis operative in cancer cells.


Assuntos
Neoplasias da Mama/fisiopatologia , Neoplasias do Colo/fisiopatologia , Melanoma/fisiopatologia , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Animais , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Transição Epitelial-Mesenquimal/fisiologia , Humanos , Melanoma/tratamento farmacológico , Doadores de Óxido Nítrico/uso terapêutico , Microambiente Tumoral/fisiologia
10.
Cell Biol Int ; 43(5): 574-579, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30761646

RESUMO

Although interleukin-24 (IL-24) has been extensively explored in the immunopathologies of autoimmune diseases, neoplasms, and infections, its role in HIV-1 infection has not been thoroughly elucidated to date. Therefore, the objective of this study was to evaluate the gene and protein expressions of IL-24 at the initial moments of HIV infection in PBMCs. Due to the pro-apoptotic role of IL-24, we evaluated the protein expression of caspase-3, as well as Annexin V/Propidium Iodide flow cytometry and phosphorylation of ERK, which may induce an apoptotic signal block when phosphorylated. The results of this study demonstrated that HIV-1 infection had an impact on the gene and protein expressions of IL-24 and ERK. Annexin V/Propidium Iodide assay demonstrated decrease in the mechanisms of apoptosis in infected cells after incubation of IL-24 neutralizing antibody. Studies on how HIV-1 regulates IL-24 expression may play a role in characterizing viral persistence mechanisms and designing antiretroviral strategies.


Assuntos
Infecções por HIV/imunologia , HIV-1/imunologia , Interleucinas/imunologia , Anexina A5/imunologia , Apoptose/fisiologia , Células Sanguíneas/imunologia , Caspase 3/imunologia , Humanos , Proteína Quinase 3 Ativada por Mitógeno/imunologia , Cultura Primária de Células
11.
J Cell Physiol ; 233(4): 3176-3194, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28833096

RESUMO

We investigated the role of glycosaminoglycans (GAGs) in the regulation of endothelial nitric oxide synthase (eNOS) activity in wild-type CHO-K1 cells and in xylosyltransferase-deficient CHO-745 cells. GAGs inhibit the integrin/FAK/PI3K/AKT signaling pathway in CHO-K1 cells, decreasing the phosphorylation of eNOS at Ser1177. Furthermore, in CHO-K1 cells, eNOS and PKCα are localized at sphingolipid- and cholesterol-rich domains in the plasma membrane called caveolae. At caveolae, PKCα activation stimulates the phosphorylation of eNOS on Thr495, resulting in further inhibition of NO production in these cells. In our data, CHO-745 cells generate approximately 12-fold more NO than CHO-K1 cells. Increased NO production in CHO-745 cells promotes higher rates of protein S-nitrosylation and protein tyrosine nitration. Regarding reactive oxygen species (ROS) production, CHO-745 cells show lower basal levels of superoxide (O2- ) than CHO-K1 cells. In addition, CHO-745 cells express higher levels of GPx, Trx1, and catalase than CHO-K1 cells, suggesting that CHO-745 cells are in a constitutive nitrosative/oxidative stress condition. Accordingly, we showed that CHO-745 cells are more sensitive to oxidant-induced cell death than CHO-K1 cells. The high concentration of NO and reactive oxygen species generated by CHO-745 cells can induce simultaneous mitochondrial biogenesis and antioxidant gene expression. These observations led us to propose that GAGs are part of a regulatory mechanism that participates in eNOS activation and consequently regulates nitrosative/oxidative stress in CHO cells.


Assuntos
Proteoglicanas de Heparan Sulfato/deficiência , Espaço Intracelular/metabolismo , Óxido Nítrico/biossíntese , Regulação para Cima , Animais , Células CHO , Cricetinae , Cricetulus , Células Endoteliais/metabolismo , Matriz Extracelular/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Oligopeptídeos/metabolismo , Biogênese de Organelas , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Frações Subcelulares/metabolismo
12.
Cell Biol Int ; 40(7): 796-802, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27109745

RESUMO

Much attention has been drawn to the pro-inflammatory condition that accompanies aging. This study compared parameters from non-stimulated neutrophils, obtained from young (18-30 years old [y.o.]) and elderly (65-80 y.o.) human volunteers. Measured as an inflammatory marker, plasmatic concentration of hs-CRP was found higher in elderly individuals. Non-stimulated neutrophil production of ROS and NO was, respectively, 38 and 29% higher for the aged group. From the adhesion molecules evaluated, only CD11b expression was elevated in neutrophils from the aged group, whereas no differences were found for CD11a, CD18, or CD62. A 69% higher non-stimulated in vitro neutrophil/endothelial cell adhesion was observed for neutrophils isolated from elderly donors. Our results suggest that with aging, neutrophils may be constitutively producing more reactive species in closer proximity to endothelial cells of vessel walls, which may both contribute to vascular damage and reflect a neutrophil intracellular disrupted redox balance, altering neutrophil function in aging.


Assuntos
Células Endoteliais/citologia , Neutrófilos/citologia , Adulto , Fatores Etários , Idoso , Envelhecimento/fisiologia , Antígenos CD/metabolismo , Proteína C-Reativa/metabolismo , Antígeno CD11b/metabolismo , Adesão Celular/fisiologia , Moléculas de Adesão Celular/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Feminino , Humanos , Masculino , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
13.
Nitric Oxide ; 47: 40-51, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25819133

RESUMO

The small GTP-binding proteins Ras and Rac1 are molecular switches exchanging GDP for GTP and converting external signals in response to a variety of stimuli. Ras and Rac1 play an important role in cell proliferation, cell differentiation, and cell migration. Rac1 is directly involved in the reorganization and changes in the cytoskeleton during cell motility. Nitric oxide (NO) stimulates the Ras - ERK1/2 MAP kinases signaling pathway and is involved in the interaction between Ras and the phosphatidyl-inositol-3 Kinase (PI3K) signaling pathway and cell migration. This study utilizes bradykinin (BK), which promotes endogenous production of NO, in an investigation of the role of NO in the activation of Rac1 in rabbit aortic endothelial cells (RAEC). NO-derived from BK stimulation of RAEC and incubation of the cells with the s-nitrosothiol S-nitrosoglutathione (GSNO) activated Rac1. NO-derived from BK stimulation promoted RAEC migration over a period of 12 h. The use of RAEC permanently transfected with the dominant negative mutant of Ras (Ras(N17)) or with the non-nitrosatable mutant of Ras (Ras(C118S)); and the use of specific inhibitors of: Ras, PI3K, and Rac1 resulted in inhibition of NO-mediated Rac1 activation. BK-stimulated s-nitrosylation of Ras in RAEC mediates Rac1 activation and cell migration. Inhibition of NO-mediated Rac1 activation resulted in inhibition of endothelial cell migration. In conclusion, the NO indirect activation of Rac1 involves the direct participation of Ras and PI3K in the migration of endothelial cells stimulated with BK.


Assuntos
Movimento Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Óxido Nítrico/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteínas ras/metabolismo , Bradicinina/farmacologia , Células Endoteliais/metabolismo , Humanos , Óxido Nítrico/biossíntese
14.
World J Microbiol Biotechnol ; 31(3): 445-51, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25588525

RESUMO

Methanol, n-hexane and dichloromethane extracts of twelve marine macro-algae (Rhodophyta, Chlorophyta and Heterokontophyta divisions) from Peniche coast (Portugal) were evaluated for their antibacterial and antifungal activity. The antibacterial activity was evaluated by disc diffusion method against Bacillus subtilis (gram positive bacteria) and Escherichia coli (gram negative bacteria). Saccharomyces cerevisiae was used as a model for the antifungal activity by evaluating the growth inhibitory activity of the extracts. The high antibacterial activity was obtained by the Asparagopsis armata methanolic extract (10 mm-0.1 mg/disc), followed by the Sphaerococcus coronopifolius n-hexane extract (8 mm-0.1 mg/disc), and the Asparagopsis armata dichloromethane extract (12 mm-0.3 mg/disc) against Bacillus subtilis. There were no positive results against Escherichia coli. Sphaerococcus coronopifolius revealed high antifungal potential for n-hexane (IC50 = 40.2 µg/ml), dichloromethane (IC50 = 78.9 µg/ml) and methanolic (IC50 = 55.18 µg/ml) extracts against Saccharomyces cerevisiae growth. The antifungal potency of the Sphaerococcus coronopifolius extracts was similar with the standard amphotericin B. Asparagopsis armata and Sphaerococcus coronopifolius reveal to be interesting sources of natural compounds with antimicrobial properties.


Assuntos
Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Rodófitas/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Extratos Celulares/isolamento & purificação , Extratos Celulares/farmacologia , Escherichia coli/efeitos dos fármacos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Portugal , Rodófitas/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos
15.
Arch Biochem Biophys ; 558: 14-27, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24960080

RESUMO

Nitric oxide (NO) is involved in angiogenesis and stimulates the EGF-R signaling pathway. Stimulation of different endothelial cell lines with bradykinin (BK) activates the endothelial NO synthase (eNOS) and promotes EGF-R tyrosine phosphorylation. Increase in NO production correlated with enhanced phosphorylation of tyrosine residues and S-nitrosylation of the EGF-R. NO-mediated stimulatory effects on tyrosine phosphorylation of the EGF-R, where cGMP independent. Inhibition of soluble guanylyl cyclase followed by BK stimulation of human umbilical vein endothelial cells (HUVECs) did not change tyrosine phosphorylation levels of EGF-R. BK-stimulation of HUVEC promoted S-nitrosylation of the phosphatase SHP-1 and of p21Ras. Phosphorylation and activation of the ERK1/2 MAP kinases mediated by BK was dependent on the activation of the B2 receptor, of the EGF-R, and of p21 Ras. Inhibition of BK-stimulated S-nitrosylation prevented the activation of the ERK1/2 MAP kinases. Furthermore, activated ERK1/2 MAP kinases inhibited internalization of EGF-R by phosphorylating specific Thr residues of its cytoplasmic domain. BK-induced proliferation of endothelial cells was partially inhibited by the NOS inhibitor (L-NAME) and by the MEK inhibitor (PD98059). BK stimulated the expression of vascular endothelial growth factor (VEGF). VEGF expression was dependent on the activation of the EGF-R, the B2 receptor, p21Ras, and on NO generation. A Matrigel®-based in vitro assay for angiogenesis showed that BK induced the formation of capillary-like structures in HUVEC, but not in those cells expressing a mutant of the EGF-R lacking tyrosine kinase activity. Additionally, pre-treatment of BK-stimulated HUVEC with L-NAME, PD98059, and with SU5416, a specific inhibitor of VEGFR resulted in inhibition of in vitro angiogenesis. Our findings indicate that BK-mediated angiogenesis in endothelial cells involves the induction of the expression of VEGF associated with the activation of the NO/EGF-R/p21Ras/ERK1/2 MAP kinases signaling pathway.


Assuntos
Indutores da Angiogênese/farmacologia , Bradicinina/farmacologia , Receptores ErbB/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Óxido Nítrico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Receptores ErbB/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Óxido Nítrico/biossíntese , Fosforilação/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Coelhos , S-Nitrosotióis/metabolismo , Tirosina/metabolismo
16.
Front Med (Lausanne) ; 11: 1273304, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681055

RESUMO

Introduction: Anticoagulation is recommended for stroke prevention in patients with atrial fibrillation (AF). The guidelines suggest non-vitamin K antagonist anticoagulants (NOACs) as the primary therapy for anticoagulation in AF. Several patient-related factors increase the risk of thrombotic events: elderly individuals, a previous history of stroke, and chronic kidney disease. This study aims to determine the association between NOACs and other patient variables in AF and the occurrence of thrombotic events. Methods: The database included all adults with the code K78 (ICPC-2 code for AF) who received clinical care in Northern Portugal's Primary Health Care between January 2016 and December 2018 and were dispensed the same NOAC at the pharmacy. Results: The results indicate that 10.2% of AF patients on NOAC anticoagulation experienced a stroke. Furthermore, patients treated with apixaban and dabigatran had higher odds of experiencing a stroke compared to those treated with rivaroxaban. Among patients with the same age, gender, and CHA2DS2Vasc Score, apixaban was significantly associated with a higher likelihood of thrombotic events than rivaroxaban. Discussion: These results have not been previously reported in studies with real-world data; therefore, a more detailed analysis should be conducted to enhance the validity of these findings.

17.
BMJ Open ; 14(4): e076108, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38688672

RESUMO

OBJECTIVES: This study aimed to assess the appropriateness of prescribing profiles and intake adherence to non-vitamin K antagonist oral anticoagulants (NOACs) in patients with atrial fibrillation (AF). DESIGN: Retrospective longitudinal study. SETTING: The study was conducted in the Regional Health Administration of Northern Portugal. PARTICIPANTS: The authors selected a database of 21 854 patients with prescriptions for NOACs between January 2016 and December 2018 and were classified with AF until December 2018. OUTCOME MEASURES: The appropriate dosage of NOAC for patients with AF divided into three categories: contraindicated, inconsistent and consistent, based on the 2020 European Society of Cardiology guidelines for AF. RESULTS: Dabigatran had a lower percentage of guideline-consistent doses (n=1657, 50.1%) than other drugs such as rivaroxaban (n=4737, 81.6%), apixaban (n=3830, 78.7%) and edoxaban (n=436, 82.1%). Most patients with an inconsistent dose were prescribed a lower dose than recommended based on their glomerular filtration rate (GFR). Among patients younger than 75 years with GFR >60 mL/min, 59.8% (n=10 028) had an adequate GFR range, while 27.8% (n=7166) of GFR measurements from patients older than 75 years old and 29.4% (n=913) of GFR measurements from patients younger than 75 years with GFR <60 mL/min were within an adequate time range. Adherence to NOACs varied across different drugs, with 59.1% (n=540) adhering to edoxaban, 56.3% (n=5443) to rivaroxaban, 55.3% (n=3143) to dabigatran and 53.3% (n=4211) to apixaban. CONCLUSIONS: Dabigatran had the lowest percentage of guideline-consistent doses. Patients younger than 75 years with GFR >60 mL/min had the highest percentage with an adequate GFR range, while other groups who require closer GFR monitoring had lower percentages within an adequate GFR range. Adherence to NOACs differed among different drugs, with greater adherence to treatment with edoxaban and less adherence to apixaban.


Assuntos
Anticoagulantes , Fibrilação Atrial , Dabigatrana , Piridonas , Rivaroxabana , Humanos , Fibrilação Atrial/tratamento farmacológico , Idoso , Estudos Retrospectivos , Masculino , Feminino , Estudos Longitudinais , Dabigatrana/uso terapêutico , Dabigatrana/administração & dosagem , Rivaroxabana/administração & dosagem , Rivaroxabana/uso terapêutico , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Pessoa de Meia-Idade , Portugal , Piridonas/administração & dosagem , Piridonas/uso terapêutico , Idoso de 80 Anos ou mais , Administração Oral , Fidelidade a Diretrizes/estatística & dados numéricos , Pirazóis/uso terapêutico , Pirazóis/administração & dosagem , Padrões de Prática Médica/estatística & dados numéricos , Taxa de Filtração Glomerular , Tiazóis/administração & dosagem , Tiazóis/uso terapêutico , Piridinas/administração & dosagem , Piridinas/uso terapêutico , Adesão à Medicação/estatística & dados numéricos , Inibidores do Fator Xa/uso terapêutico , Inibidores do Fator Xa/administração & dosagem
18.
Theriogenology ; 225: 172-179, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38810343

RESUMO

Nocardioform placentitis is a poorly understood disease of equine late gestation. The presence of nocardioform, filamentous branching gram-positive bacteria, has been linked to the disease, with Crossiella equi, Amycolatopsis spp., and Streptomyces spp. being the most frequently identified bacteria. However, these bacteria are not found in all clinical cases in addition to being isolated from healthy, normal postpartum placentas. To better understand this form of placentitis, we analyzed the microbial composition in the equine placenta (chorioallantois) of both healthy postpartum (control; n = 11) and nocardioform-affected samples (n = 22) using 16S rDNA sequencing. We found a lower Shannon index in nocardioform samples, a higher Chao1 index in nocardioform samples, and a difference in beta diversity between control and nocardioform samples (p < 0.05), suggesting the presence of dysbiosis during the disease. In the majority of the NP samples (77 %), one of the following genera-Amycolatopsis, Crossiella, Lentzea, an unidentified member of the Pseudonocardiaceae family, Mycobacterium, or Enterococcus -represented over 70 % of the relative abundance. Overall, the data suggest that a broader spectrum of potential opportunistic pathogens could be involved in nocardioform placentitis, extending beyond the traditionally recognized bacteria, resulting in a similar histomorphological profile.


Assuntos
Doenças dos Cavalos , Doenças Placentárias , Placenta , Animais , Cavalos , Feminino , Doenças dos Cavalos/microbiologia , Doenças dos Cavalos/patologia , Gravidez , Doenças Placentárias/veterinária , Doenças Placentárias/microbiologia , Doenças Placentárias/patologia , Placenta/microbiologia , Nocardiose/veterinária , Nocardiose/microbiologia , Nocardiose/patologia , RNA Ribossômico 16S/genética
19.
Sci Rep ; 14(1): 11864, 2024 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789554

RESUMO

Objectives were to assess differences in uterine microbiome associated with clinical cure and pregnancy outcomes in dairy cows treated for metritis. Cows with metritis (reddish-brownish, watery, and fetid vaginal discharge) were paired with cows without metritis based on parity and days postpartum. Uterine contents were collected through transcervical lavage at diagnosis, five days later following antimicrobial therapy (day 5), and at 40 days postpartum. Uterine microbiome was assessed by sequencing the V4 hypervariable region of the 16S rRNA gene. Although alpha-diversity based on Chao1, Shannon, and inverse Simpson indexes at diagnosis did not differ between cows with and without metritis, disease was associated with differences in beta-diversity. Prevalence of Porphyromonas, Bacteroides, and Veillonella was greater in cows with metritis. Streptococcus, Sphingomonas, and Ureaplasma were more prevalent in cows without metritis. Differences in beta-diversity between cows with and without metritis persisted on day 5. Uterine microbiome was not associated with clinical cure. Richness and alpha-diversity, but not beta-diversity, of uterine microbiome 40 days postpartum were associated with metritis and pregnancy. No relationship between uterine microbiome and pregnancy outcomes was observed. Results indicate that factors other than changes in intrauterine bacterial community underlie fertility loss and clinical cure in cows with metritis.


Assuntos
Doenças dos Bovinos , Endometrite , Microbiota , Resultado da Gravidez , RNA Ribossômico 16S , Útero , Feminino , Animais , Bovinos , Gravidez , Útero/microbiologia , Endometrite/microbiologia , Endometrite/veterinária , Endometrite/tratamento farmacológico , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/terapia , RNA Ribossômico 16S/genética , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação
20.
Commun Biol ; 7(1): 179, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38351154

RESUMO

The translocated intimin receptor (Tir) is an essential type III secretion system (T3SS) effector of attaching and effacing pathogens contributing to the global foodborne disease burden. Tir acts as a cell-surface receptor in host cells, rewiring intracellular processes by targeting multiple host proteins. We investigated the molecular basis for Tir's binding diversity in signalling, finding that Tir is a disordered protein with host-like binding motifs. Unexpectedly, also are several other T3SS effectors. By an integrative approach, we reveal that Tir dimerises via an antiparallel OB-fold within a highly disordered N-terminal cytosolic domain. Also, it has a long disordered C-terminal cytosolic domain partially structured at host-like motifs that bind lipids. Membrane affinity depends on lipid composition and phosphorylation, highlighting a previously unrecognised host interaction impacting Tir-induced actin polymerisation and cell death. Furthermore, multi-site tyrosine phosphorylation enables Tir to engage host SH2 domains in a multivalent fuzzy complex, consistent with Tir's scaffolding role and binding promiscuity. Our findings provide insights into the intracellular Tir domains, highlighting the ability of T3SS effectors to exploit host-like protein disorder as a strategy for host evasion.


Assuntos
Proteínas de Escherichia coli , Proteínas de Escherichia coli/metabolismo , Proteínas de Transporte , Receptores de Superfície Celular/metabolismo
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