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1.
Bull Math Biol ; 85(5): 40, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-37022524

RESUMO

Polyploidization is an evolutionary process by which a species acquires multiple copies of its complete set of chromosomes. The reticulate nature of the signal left behind by it means that phylogenetic networks offer themselves as a framework to reconstruct the evolutionary past of species affected by it. The main strategy for doing this is to first construct a so-called multiple-labelled tree and to then somehow derive such a network from it. The following question therefore arises: How much can be said about that past if such a tree is not readily available? By viewing a polyploid dataset as a certain vector which we call a ploidy (level) profile, we show that among other results, there always exists a phylogenetic network in the form of a beaded phylogenetic tree with additional arcs that realizes a given ploidy profile. Intriguingly, the two end vertices of almost all of these additional arcs can be interpreted as having co-existed in time thereby adding biological realism to our network, a feature that is, in general, not enjoyed by phylogenetic networks. In addition, we show that our network may be viewed as a generator of ploidy profile space, a novel concept similar to phylogenetic tree space that we introduce to be able to compare phylogenetic networks that realize one and the same ploidy profile. We illustrate our findings in terms of a publicly available Viola dataset.


Assuntos
Conceitos Matemáticos , Modelos Biológicos , Filogenia , Evolução Biológica , Tempo , Modelos Genéticos , Algoritmos
2.
J Math Biol ; 85(3): 30, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-36114394

RESUMO

Polyploidization, whereby an organism inherits multiple copies of the genome of their parents, is an important evolutionary event that has been observed in plants and animals. One way to study such events is in terms of the ploidy number of the species that make up a dataset of interest. It is therefore natural to ask: How much information about the evolutionary past of the set of species that form a dataset can be gleaned from the ploidy numbers of the species? To help answer this question, we introduce and study the novel concept of a ploidy profile which allows us to formalize it in terms of a multiplicity vector indexed by the species the dataset is comprised of. Using the framework of a phylogenetic network, we present a closed formula for computing the hybrid number (i.e. the minimal number of polyploidization events required to explain a ploidy profile) of a large class of ploidy profiles. This formula relies on the construction of a certain phylogenetic network from the simplification sequence of a ploidy profile and the hybrid number of the ploidy profile with which this construction is initialized. Both of them can be computed easily in case the ploidy numbers that make up the ploidy profile are not too large. To help illustrate the applicability of our approach, we apply it to a simplified version of a publicly available Viola dataset.


Assuntos
Genoma , Ploidias , Animais , Filogenia
3.
Occup Med (Lond) ; 71(2): 86-94, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33598681

RESUMO

BACKGROUND: Emerging cross-sectional reports find that the COVID-19 pandemic and related social restrictions negatively affect lifestyle behaviours and mental health in general populations. AIMS: To study the longitudinal impact of COVID-19 on work practices, lifestyle and well-being among desk workers during shelter-at-home restrictions. METHODS: We added follow-up after completion of a clinical trial among desk workers to longitudinally measure sedentary behaviour, physical activity, sleep, diet, mood, quality of life and work-related health using validated questionnaires and surveys. We compared outcomes assessed before and during COVID-19 shelter-at-home restrictions. We assessed whether changes in outcomes differed by remote working status (always, changed to or never remote) using analysis of covariance (ANCOVA). RESULTS: Participants (N = 112; 69% female; mean (SD) age = 45.4 (12.3) years; follow-up = 13.5 (6.8) months) had substantial changes to work practices, including 72% changing to remote work. Deleterious changes from before to during shelter-at-home included: 1.3 (3.5)-h increase in non-workday sedentary behaviour; 0.7 (2.8)-point worsening of sleep quality; 8.5 (21.2)-point increase in mood disturbance; reductions in five of eight quality of life subscales; 0.5 (1.1)-point decrease in work-related health (P < 0.05). Other outcomes, including diet, physical activity and workday sedentary behaviour, remained stable (P ≥ 0.05). Workers who were remote before and during the pandemic had greater increases in non-workday sedentary behaviour and stress, with greater declines in physical functioning. Wake time was delayed overall by 41 (61) min, and more so in workers who changed to remote. CONCLUSIONS: Employers should consider supporting healthy lifestyle and well-being among desk workers during pandemic-related social restrictions, regardless of remote working status.


Assuntos
COVID-19 , Controle de Doenças Transmissíveis/métodos , Estilo de Vida , Ocupações , Pandemias , Qualidade de Vida , Trabalho , Adulto , Afeto , Dieta , Exercício Físico , Feminino , Nível de Saúde , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Transtornos do Humor/etiologia , SARS-CoV-2 , Comportamento Sedentário , Sono , Estresse Psicológico , Inquéritos e Questionários
4.
J Dairy Sci ; 102(12): 11718-11729, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563314

RESUMO

Adipose tissue response to endocrine stimuli, such as insulin, is crucial for metabolic adaptation at the onset of lactation in dairy cows. However, the exact molecular mechanisms behind this response are not well understood. Thus, the aim of this study was to determine the dynamics in protein expression and phosphorylation of key components in insulin signaling in subcutaneous (SCAT) and retroperitoneal (RPAT) adipose tissues of Holstein dairy cows. Furthermore, by ex vivo examinations, response to insulin was assessed in SCAT and RPAT at different time points during the periparturient period. Biopsy samples were taken 42 d prepartum, and 1, 21, and 100 d postpartum. Insulin and glucose concentrations were measured in blood serum in consecutive serum samples from d -42 until d +100. After parturition, the majority of the key components were downregulated in both adipose tissues but recovered by d +100. The extent of hormone-sensitive lipase phosphorylation increased postpartum and remained high throughout the experimental period. Strong differences in molecular response were observed between the 2 depots. The RPAT expressed a remarkably greater extent of AMP-activated kinase phosphorylation compared with SCAT, indicating that AMP-activated kinase as an energy sensor is highly active particularly in RPAT in times of energy scarcity. Consequently, this depot expressed a greater extent of hormone-sensitive lipase phosphorylation over the whole experimental period. Insulin response after parturition appeared to be greater in RPAT too, due to the significantly greater expression of the insulin receptor at d +21 and +100. Although insulin concentrations in plasma were low postpartum, the depot-specific changes in molecular modulation of insulin signaling and insulin response suggested that both adipose tissue depots studied were contributing to the periparturient homeorhetic adaptation, although most likely to a different extent.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Bovinos/fisiologia , Insulina/sangue , Receptor de Insulina/metabolismo , Transdução de Sinais , Esterol Esterase/metabolismo , Animais , Glicemia/análise , Dieta/veterinária , Feminino , Gordura Intra-Abdominal/metabolismo , Lactação , Parto , Fosforilação , Período Pós-Parto
5.
Vascul Pharmacol ; 110: 49-54, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30098417

RESUMO

BACKGROUND AND AIMS: Macrophages are versatile immune cells involved in tissue degradation and remodeling. Proinflammatory macrophages have the highest capacity of matrix degradation and proteolysis. Within atherosclerotic lesions, proinflammatory macrophages are associated with unstable plaques. Statins have been demonstrated to increase plaque stability. Possible changes of polarized macrophage tissue degradation behavior under statin treatment are currently unknown. METHODS: Polarized macrophages were tested in vitro for matrix degradation capacity with or without statin treatment. RESULTS: Proinflammatory macrophages show high matrix degradation capacity, which is lost after statin treatment. Statin concentrations were within a physiological range and did not influence overall macrophage polarization. Proinflammatory macrophages showed however a loss of filopodia where activators of MMPs are located. Loss of matrix degradation in proinflammatory macrophages was associated with changes of MMP14 activation and loss of uPAR localization at filopodia. Supplementation of mevalonate restored localization of uPAR to cellular protrusions and matrix degradation capacity. CONCLUSION: Statins reduce the matrix degradation potential of proinflammatory macrophages by reducing uPAR localization to cellular filopodia and reducing intracellular MMP14 activation.


Assuntos
Anti-Inflamatórios/farmacologia , Atorvastatina/farmacologia , Plasticidade Celular , Matriz Extracelular/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Células Cultivadas , Matriz Extracelular/metabolismo , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Metaloproteinase 14 da Matriz/metabolismo , Fenótipo , Proteólise/efeitos dos fármacos , Pseudópodes/efeitos dos fármacos , Pseudópodes/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/efeitos dos fármacos , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo
6.
Leukemia ; 31(11): 2388-2397, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28757617

RESUMO

The BCR/ABL1 inhibitor Nilotinib is increasingly used to treat patients with chronic myeloid leukemia (CML). Although otherwise well-tolerated, Nilotinib has been associated with the occurrence of progressive arterial occlusive disease (AOD). Our objective was to determine the exact frequency of AOD and examine in vitro and in vivo effects of Nilotinib and Imatinib on endothelial cells to explain AOD-development. In contrast to Imatinib, Nilotinib was found to upregulate pro-atherogenic adhesion-proteins (ICAM-1, E-selectin, VCAM-1) on human endothelial cells. Nilotinib also suppressed endothelial cell proliferation, migration and tube-formation and bound to a distinct set of target-kinases, relevant to angiogenesis and atherosclerosis, including angiopoietin receptor-1 TEK, ABL-2, JAK1 and MAP-kinases. Nilotinib and siRNA against ABL-2 also suppressed KDR expression. In addition, Nilotinib augmented atherosclerosis in ApoE-/- mice and blocked reperfusion and angiogenesis in a hindlimb-ischemia model of arterial occlusion, whereas Imatinib showed no comparable effects. Clinically overt AOD-events were found to accumulate over time in Nilotinib-treated patients. After a median observation-time of 2.0 years, the AOD-frequency was higher in these patients (29.4%) compared to risk factor- and age-matched controls (<5%). Together, Nilotinib exerts direct pro-atherogenic and anti-angiogenic effects on vascular endothelial cells, which may contribute to development of AOD in patients with CML.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/efeitos adversos , Pirimidinas/efeitos adversos , Doenças Vasculares/induzido quimicamente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Apolipoproteínas E/genética , Aterosclerose/induzido quimicamente , Endotélio Vascular/citologia , Feminino , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade
7.
Adv Cancer Res ; 134: 117-132, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28110648

RESUMO

Metabolomics is a rapidly evolving and a promising research field with the expectation to improve diagnosis, therapeutic treatment prediction, and prognosis of particular diseases. Among all techniques used to assess the metabolome in biological systems, mass spectrometry imaging is the method of choice to qualitatively and quantitatively analyze metabolite distribution in tissues with a high spatial resolution, thus providing molecular data in relation to cancer histopathology. The technique is ideally suited to study tissues molecular content and is able to provide molecular biomarkers or specific mass signatures which can be used in classification or the prognostic evaluation of tumors. Recently, it was shown that FFPE tissue samples are also suitable for metabolic analyses. This progress in methodology allows access to a highly valuable resource of tissues believed to widen and strengthen metabolic discovery-driven studies.


Assuntos
Biomarcadores Tumorais/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Espectrometria de Massas/métodos , Metaboloma , Metabolômica/métodos , Imagem Molecular/métodos , Neoplasias/patologia , Animais , Humanos , Neoplasias/metabolismo
8.
Vet Immunol Immunopathol ; 179: 36-45, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27590424

RESUMO

The periparturient period of dairy cows is accompanied by an immunosuppression that leaves the animal more susceptible to infections and metabolic disorders. Non-esterified fatty acids (NEFA) and beta-hydroxybutyrate (BHB) which peak shortly after parturition due to lipolysis are known to impair immune cell functions. Niacin with its well-known anti-lipolytic effect may have the ability to ameliorate this situation. Additionally, niacin shows also anti-inflammatory effects that may be beneficial to the immune status of the cow. To address this 29 multiparous and 18 primiparous German Holstein cows were subjected to four different feeding groups. They were fed either a ration with a high concentrate proportion of 60% (HC), or a low concentrate proportion of 30% (LC). After parturition both concentrate levels were reduced to 30% and increased again to 50% either within 16days (LC-group) or within 24days (HC-group). Half of the animals received either 24g per day of nicotinic acid from 42days prepartum until 24days postpartum (LC-NA, HC-NA) or no supplement (LC-CON, HC-CON). Apoptosis in polymorphonuclear leukocytes (PMN) and peripheral blood mononuclear cells (PBMC) was examined with an Annexin V and propidium iodide (PI) based fluorescence flow cytometry assay and distinguished into early apoptotic (Annexin V positive and PI negative) and late apoptotic (Annexin V and PI positive) cells. Additionally, the pro-apoptotic gene BAX, the effector caspase CASP3, and the anti-apoptotic genes BCL2 and BCL-xL, as well as the NFκB subunit RELA were quantified by real-time PCR in blood leukocytes. All variables showed time dependencies that were mainly related to parturition (p<0.01). Early apoptotic PBMC were significantly affected by concentrate level showing higher numbers of apoptotic cells in the HC groups (p=0.029). PBMC were characterized by a more pronounced apoptosis than PMN and seemed to be more susceptible to the changes that occur around parturition. The genes BAX and CASP3 were positively correlated (0.631) and their peak preceded the apoptotic peak around parturition in the blood leukocytes. The LC animals showed a decrease in BCL2 expression before parturition, whereas the HC animals showed a continuous increase in BCL2 mRNA abundance (p=0.059). RELA correlated stronger with the pro-apoptotic genes (0.715 and 0.650 with BAX and CASP3 respectively) and its expression was higher in primiparous than in multiparous cows (p=0.011). Nicotinic acid supplementation did show some influence in increasing numbers of early apoptotic PMN and late apoptotic PBMC between 42 and 100 DIM.


Assuntos
Apoptose , Suplementos Nutricionais , Metabolismo Energético , Leucócitos/fisiologia , Niacina/administração & dosagem , Parto/metabolismo , Animais , Caspase 3/genética , Bovinos , Feminino , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/análise , Proteína X Associada a bcl-2/genética
9.
Sci Rep ; 6: 30162, 2016 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-27444882

RESUMO

Human monocytes are a heterogeneous cell population, which can be divided into a classical (CD14++CD16-), a non-classical (CD14+CD16+), and an intermediate (CD14++CD16+) subset. We hypothesized that low-grade inflammation may differentially affect monocyte subsets. We used a human lipopolysaccharide (LPS) infusion model to mimic low-grade inflammation to identify, which monocyte subsets are preferentially activated under these conditions. Monocyte subsets were identified by staining for CD14 and CD16, activation status of monocytes was analyzed by staining for CD11b and a novel in situ mRNA hybridization approach to detect IL-6 and IL-8 specific mRNA at the single-cell level by flow cytometry. After LPS challenge, cell numbers of monocyte subsets dropped after 2 h with cell numbers recovering after 6 h. Distribution of monocyte subsets was skewed dramatically towards the intermediate subset after 24 h. Furthermore, intermediate monocytes displayed the largest increase of CD11b expression after 2 h. Finally, IL-6 and IL-8 mRNA levels increased in intermediate and non-classical monocytes after 6 h whereas these mRNA levels in classical monocytes changed only marginally. In conclusion, our data indicates that the main responding subset of monocytes to standardized low-grade inflammation induced by LPS in humans is the CD14++CD16+ intermediate subset followed by the CD14+CD16+ non-classical monocyte subset. Circulating classical monocytes showed comparably less reaction to LPS challenge in vivo.


Assuntos
Endotoxemia/patologia , Inflamação/patologia , Monócitos/patologia , Contagem de Células/métodos , Endotoxemia/metabolismo , Humanos , Inflamação/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , RNA Mensageiro/metabolismo , Receptores de IgG/metabolismo
10.
Oncogene ; 35(22): 2881-92, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-26411365

RESUMO

Brain metastases (BM) are a devastating consequence of breast cancer. BM occur more frequently in patients with estrogen receptor-negative (ER-) breast cancer subtypes; HER2 overexpressing (HER2+) tumors and triple-negative (TN) (ER-, progesterone receptor-negative (PR-) and normal HER2) tumors. Young age is an independent risk factor for the development of BM, thus we speculated that higher circulating estrogens in young, pre-menopausal women could exert paracrine effects through the highly estrogen-responsive brain microenvironment. Using a TN experimental metastases model, we demonstrate that ovariectomy decreased the frequency of magnetic resonance imaging-detectable lesions by 56% as compared with estrogen supplementation, and that the combination of ovariectomy and letrozole further reduced the frequency of large lesions to 14.4% of the estrogen control. Human BM expressed 4.2-48.4% ER+ stromal area, particularly ER+ astrocytes. In vitro, E2-treated astrocytes increased proliferation, migration and invasion of 231BR-EGFP cells in an ER-dependent manner. E2 upregulated epidermal growth factor receptor (EGFR) ligands Egf, Ereg and Tgfa mRNA and protein levels in astrocytes, and activated EGFR in brain metastatic cells. Co-culture of 231BR-EGFP cells with E2-treated astrocytes led to the upregulation of the metastatic mediator S100 Calcium-binding protein A4 (S100A4) (1.78-fold, P<0.05). Exogenous EGF increased S100A4 mRNA levels in 231BR-EGFP cells (1.40±0.02-fold, P<0.01 compared with vehicle control) and an EGFR/HER2 inhibitor blocked this effect, suggesting that S100A4 is a downstream effector of EGFR activation. Short hairpin RNA-mediated S100A4 silencing in 231BR-EGFP cells decreased their migration and invasion in response to E2-CM, abolished their increased proliferation in co-cultures with E2-treated astrocytes and decreased brain metastatic colonization. Thus, S100A4 is one effector of the paracrine action of E2 in brain metastatic cells. These studies provide a novel mechanism by which estrogens, acting through ER+ astrocytes in the brain microenvironment, can promote BM of TN breast cancers, and suggests existing endocrine agents may provide some clinical benefit towards reducing and managing BM.


Assuntos
Astrócitos/patologia , Neoplasias Encefálicas/secundário , Estrogênios/metabolismo , Comunicação Parácrina , Neoplasias de Mama Triplo Negativas/patologia , Animais , Astrócitos/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Transformação Celular Neoplásica , Receptores ErbB/metabolismo , Estradiol/farmacologia , Técnicas de Silenciamento de Genes , Humanos , Camundongos , Camundongos Nus , Invasividade Neoplásica , Comunicação Parácrina/efeitos dos fármacos
11.
Biochim Biophys Acta ; 1863(2): 360-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26658719

RESUMO

Aging is a major factor predisposing for multiple diseases. Telomeres at the ends of chromosomes protect the integrity of chromosomal DNA. A specialized six-protein complex termed shelterin protects the telomere from unwanted interaction with DNA damage pathways. The aim of our study was to evaluate the integrity of telomeres and the stability of telomere protection during aging in endothelial cells (EC). We describe that aging EC can be characterized by an increased cell size (40%, p=0.02) and increased expression of PAI 1 (4 fold, p=0.02), MCP1 (10 fold, p=0.001) and GMCSF (15 fold, p=0.004). Telomeric state in aging cells is defined by an increased telomere oxidation (27%, p=0.01), reduced telomere length (62%, p=0.02), and increased DNA damage foci formation (5% in young EC versus 16% in aged EC, p=0.003). This telomeric dysfunction is accompanied by a reduction in the shelterin component TRF1 (33% mRNA, p=0.001; 24% protein, p=0.007). Overexpression of TRF1 in aging EC reduced telomere-associated DNA damage foci to 5% (p=0.02) and reduced expression levels of MCP1 (18% reduction, p=0.008). Aged EC have increased telomere damage and an intrinsic loss of telomere protection. Reestablishing telomere integrity could therefore be a target for rejuvenating endothelial cell function.


Assuntos
Senescência Celular/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Telômero/genética , Proteína 1 de Ligação a Repetições Teloméricas/genética , Western Blotting , Células Cultivadas , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Dano ao DNA , Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Hibridização in Situ Fluorescente , Microscopia Confocal , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Telômero/metabolismo , Proteína 1 de Ligação a Repetições Teloméricas/metabolismo
12.
J Dairy Sci ; 99(2): 1549-1559, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26686707

RESUMO

The transition from pregnancy to lactation is characterized by major changes in glucose and adipose tissue metabolism. Anti- and prolipolytic pathways mediated via the hydroxycarboxylic acid receptors 1 (HCAR1) and 2 (HCAR2) and tumor necrosis factor-α receptor 1 (TNFR1), as well as the adipokines apelin and resistin, are likely involved in regulating these processes. This study aimed to determine the mRNA abundance of the aforementioned receptors in both subcutaneous and visceral adipose tissue, to characterize the adipokine concentrations in serum, and to test the effects of feeding diets with either high or low portions of concentrate and a concomitant niacin supplementation from late gestation to early lactation. Twenty pluriparous German Holstein cows were all kept on the same silage-based diet until d 42 antepartum, when they were allocated to 2 feeding groups: until d 1 antepartum, 10 animals each were assigned to either a high-concentrate (60:40 concentrate-to-roughage ratio) or a low-concentrate diet (30:70). Both groups were further subdivided into a control and a niacin group, the latter receiving 24 g/d of nicotinic acid from d -42 until 24. From d 1 to 24 postpartum, the concentrate portion was increased from 30 to 50% for all cows. Biopsies of subcutaneous (SCAT) and retroperitoneal adipose tissue (RPAT) were taken at d -42, 1, 21, and 100 relative to parturition. Blood samples were drawn along with the biopsies and on d -14, 3, 7, 14, and 42. The concentrations of the adipokines apelin and resistin in serum were measured via ELISA. The mRNA of the 3 receptors in AT was quantified as well as the protein abundance of HCAR2 by Western blot. The feeding regimen did not affect the variables examined. The concentrations of apelin remained fairly constant during the observation period, whereas the resistin concentrations increased toward parturition and decreased to precalving levels within 1 wk after calving. The mRNA abundance of HCAR1, HCAR2, and TNFR1 changed in SCAT and RPAT during the considered time period. For the HCAR2 protein, time-dependent changes were restricted to SCAT. The mRNA abundance of all receptors was greater in RPAT than in SCAT. The tissue-specific correlations observed between the receptors point to a link between these factors and may indicate different regulatory roles in the respective tissues. This study provides insight into the complex metabolic adaptations during the transition period and supports a differential regulation of lipolysis among SCAT and RPAT in dairy cows.


Assuntos
Adipocinas/metabolismo , Tecido Adiposo/metabolismo , Bovinos/fisiologia , Gordura Intra-Abdominal/metabolismo , Resistina/metabolismo , Adipocinas/genética , Animais , Dieta/veterinária , Fibras na Dieta/análise , Suplementos Nutricionais/análise , Feminino , Lactação , Lipólise , Parto , Período Pós-Parto , Gravidez , Receptores de Adipocina/genética , Receptores de Adipocina/metabolismo , Resistina/genética , Silagem/análise
13.
J Anim Sci ; 93(8): 4012-22, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26440181

RESUMO

Dairy cattle will mobilize large amounts of body fat during early lactation as an effect of decreased lipogenesis and increased lipolysis. Regulation of lipid metabolism involves fatty acid synthesis from acetate and ß-adrenergic-stimulated phosphorylation of hormone-sensitive lipase (HSL) and perilipin in adipocytes. Although basic mechanisms of mobilizing fat storage in transition cows are understood, we lack a sufficiently detailed understanding to declare the exact regulatory network of these in a broad range of dairy cattle. The objective of the present study was to quantify 1) protein abundance of fatty acid synthase (FAS), 2) extent of phosphorylation of HSL and perilipin in vivo, and 3) ß-adrenergic stimulated lipolytic response of adipose tissues in vitro at different stages of the periparturient period. We fed 20 German Holstein cows an energy-dense or an energetically adequate diet prepartum and 0 or 24 g/d nicotinic acid (NA) supplementation. Biopsy samples of subcutaneous and retroperitoneal adipose tissue were obtained at d 42 prepartum (d -42) and at d 1, 21, and 100 postpartum (d +1, d +21, d +100, respectively). To assess ß-adrenergic response, tissue samples were incubated with 1 µ isoproterenol for 90 min at 37°C. The NEFA and glycerol release, as well as HSL and perilipin phosphorylation, was measured as indicators of in vitro stimulated lipolysis. In addition, protein expression of FAS and extent of HSL and perilipin phosphorylation were measured in fresh, nonincubated samples. There was no effect of dietary energy density or NA on the observed variables. The extent of HSL and perilipin phosphorylation under isoproterenol stimulation was strongly correlated with the release of NEFA and glycerol, consistent with the functional link between ß-adrenergic-stimulated protein phosphorylation and lipolysis. In the nonincubated samples, FAS protein expression was decreased at d +1 and d +21, whereas HSL and perilipin phosphorylation increased from d -42 to d +1 and remained at an increased level throughout the first 100 d of lactation. In vitro lipolytic response was significant in prepartum samples at times when in vivo lipolysis was only minimally activated by phosphorylation. These data extend our understanding of the complex nature of control of lipolysis and lipogenesis in dairy cows and could be useful to the ongoing development of systems biology models of metabolism to help improve our quantitative knowledge of the cow.


Assuntos
Ração Animal/análise , Bovinos/metabolismo , Dieta/veterinária , Fenômenos Fisiológicos da Nutrição Animal , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Suplementos Nutricionais , Ácido Graxo Sintases/genética , Ácido Graxo Sintases/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Feminino , Regulação da Expressão Gênica/fisiologia , Niacina/administração & dosagem , Niacina/farmacologia , Perilipina-1 , Período Periparto , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosforilação/fisiologia , Gravidez , Esterol Esterase/genética , Esterol Esterase/metabolismo
14.
Cell Death Dis ; 6: e1767, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25996294

RESUMO

Necroptosis is a form of regulated necrotic cell death mediated by receptor-interacting serine/threonine-protein kinase 1 (RIPK1) and RIPK3. Necroptotic cell death contributes to the pathophysiology of several disorders involving tissue damage, including myocardial infarction, stroke and ischemia-reperfusion injury. However, no inhibitors of necroptosis are currently in clinical use. Here we performed a phenotypic screen for small-molecule inhibitors of tumor necrosis factor-alpha (TNF-α)-induced necroptosis in Fas-associated protein with death domain (FADD)-deficient Jurkat cells using a representative panel of Food and Drug Administration (FDA)-approved drugs. We identified two anti-cancer agents, ponatinib and pazopanib, as submicromolar inhibitors of necroptosis. Both compounds inhibited necroptotic cell death induced by various cell death receptor ligands in human cells, while not protecting from apoptosis. Ponatinib and pazopanib abrogated phosphorylation of mixed lineage kinase domain-like protein (MLKL) upon TNF-α-induced necroptosis, indicating that both agents target a component upstream of MLKL. An unbiased chemical proteomic approach determined the cellular target spectrum of ponatinib, revealing key members of the necroptosis signaling pathway. We validated RIPK1, RIPK3 and transforming growth factor-ß-activated kinase 1 (TAK1) as novel, direct targets of ponatinib by using competitive binding, cellular thermal shift and recombinant kinase assays. Ponatinib inhibited both RIPK1 and RIPK3, while pazopanib preferentially targeted RIPK1. The identification of the FDA-approved drugs ponatinib and pazopanib as cellular inhibitors of necroptosis highlights them as potentially interesting for the treatment of pathologies caused or aggravated by necroptotic cell death.


Assuntos
Imidazóis/farmacologia , Necrose/tratamento farmacológico , Piridazinas/farmacologia , Pirimidinas/farmacologia , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Sulfonamidas/farmacologia , Células 3T3 , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proteína de Domínio de Morte Associada a Fas/genética , Células HEK293 , Células HT29 , Humanos , Indazóis , Células Jurkat , Células L , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/metabolismo , Camundongos , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
15.
Int J Cosmet Sci ; 37(1): 129-33, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25256809

RESUMO

BACKGROUND: The skin is the first line of defence against exposure to microbial, physical, environmental and chemical insults. In mobilizing a protective response, several different cell types located in our skin release and respond to pro-inflammatory cytokines ensuring skin homeostasis and health. However, chronic activation of this response eventually causes damage resulting in premature ageing. Diosodium tetramethylhexadecenyl succinyl cysteine (TSC or SIG1273), an isoprenylcysteine small molecule, down modulates these inflammatory signalling pathways in various cell types (keratinocytes, peripheral blood mononuclear cells (PBMCs) and endothelial cells) and possesses anti-bacterial properties. Thus, TSC represents a novel cosmetic functional ingredient that provides a broad spectrum of benefits for the skin. OBJECTIVE: To assess the anti-inflammatory properties of TSC in several cutaneous cell types and further investigate its anti-microbial activity. METHODS: Cultured normal human epidermal keratinocytes were exposed to chemical irritant phorbol 12-myrisate 13-acetate (TPA) or ultraviolet-B light (UVB) to induce pro-inflammatory cytokine (IL-6, IL-8 and TNF-α) production. T-cell receptor (TCR) activation of PBMCs and nickel (Ni(2+) ) treatments of human dermal microvascular endothelial cells (HDMECs) were performed resulting in IL-4, IL-6, IL-8 and IL-17 production. Streptococcus pyogenes were cultured to determine minimal inhibitory concentration values. RESULTS: In vitro studies demonstrate TSC blocks TPA and UVB-induced cytokine production in cultured keratinocytes. Similarly, TSC inhibits overproduction of IL-4 and IL-17 in T-cell receptor (TCR)-activated PBMCs as well as nickel induction of IL-6 and IL-8 in HDMECs. Lastly, TSC demonstrated anti-microbial properties, inhibiting cell growth of S. pyogenes. CONCLUSIONS: Tetramethylhexadecenyl succinyl cysteine represents a novel cosmetic functional ingredient that provides a dual modulating benefit of skin protection to individuals by reducing inflammation in keratinocytes, endothelial and mononuclear cell types and S. pyogenes counts.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Cosméticos , Cisteína/análogos & derivados , Células Cultivadas , Cisteína/química , Humanos
16.
Thromb Res ; 135(2): 329-33, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25496999

RESUMO

INTRODUCTION: Reports on the content of aspirated coronary thrombi have until now mainly focused on cellular components. We investigated the genetic expression of selected mediators and proteases actively involved in the pathophysiological process of acute myocardial infarction in aspirated coronary thrombi. MATERIALS AND METHODS: In this cross-sectional study, RNA from coronary thrombi in 67 subjects with acute myocardial infarction was isolated. Gene expression arrays of selected markers were performed by RT-PCR with relative quantification. RESULTS: Twenty of 22 markers were expressed in >50% of the samples. The relative quantification of P-selectin correlated negatively to total ischemic time (p=0.01), while genes related to fibrinolysis (t-PA, u-PA, PAI-1), inflammation (PTX3, CXCL9, MCP-1, IL18, TNFα) and plaque instability (MMP-2 and TIMP-1) correlated positively to total ischemic time (all<0.05). Long ischemic time (>4.0 hours) associated with a relative reduction in the expression of P-selectin and a relative increase in the expression of t-PA, u-PA, PAI-1, PTX3, CXCL9, MCP-1, IL-18, TNFα, MMP-2 and TIMP-1. The presence of type 2 diabetes associated with 3.2-fold increased PAI-1 expression (adjusted p=0.033), while the presence of hypertension associated with about 50% reduction of IL-8 and TIMP-1. Smoking and overweight did not affect any markers. CONCLUSIONS: The gene expression profile from coronary thrombi differed according to ischemic time, shown by reduced content of platelet markers and increased content of fibrinolytic, inflammatory and plaque instability mediators over time. Patients with type 2 diabetes showed increased expression of PAI-1, indicative of reduced fibrinolysis.


Assuntos
Trombose Coronária/genética , Infarto do Miocárdio/genética , Doença Aguda , Estudos de Coortes , Trombose Coronária/complicações , Estudos Transversais , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/fisiopatologia
17.
J Dairy Sci ; 98(2): 1057-68, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25497790

RESUMO

In response to negative energy balance, overconditioned cows mobilize more body fat than thin cows and subsequently are prone to develop metabolic disorders. Changes in adipose tissue (AT) metabolism are barely investigated in overconditioned cows. Therefore, the objective was to investigate the effect of increasing body condition on key regulator proteins of fat metabolism in subcutaneous AT and circulation of dairy cows. Nonlactating, nonpregnant dairy cows (n=8) investigated in the current study served as a model to elucidate the changes in the course of overcondition independent from physiological changes related to gestation, parturition, and lactation. Cows were fed diets with increasing portions of concentrate during the first 6wk of the experiment until 60% were reached, which was maintained for 9wk. Biopsy samples from AT of the subcutaneous tailhead region were collected every 8wk, whereas blood was sampled monthly. Within the experimental period cows had an average BW gain of 243±33.3 kg. Leptin and insulin concentrations were increased until wk 12. Based on serum concentrations of glucose, insulin, and nonesterified fatty acids, the surrogate indices for insulin sensitivity were calculated. High-concentrate feeding led to decreased quantitative insulin sensitivity check index and homeostasis model assessment due to high insulin and glucose concentrations indicating decreased insulin sensitivity. Adiponectin, an adipokine-promoting insulin sensitivity, decreased in subcutaneous AT, but remained unchanged in the circulation. The high-concentrate diet affected key enzymes reflecting AT metabolism such as AMP-activated protein kinase and hormone-sensitive lipase, both represented as the proportion of the phosphorylated protein to total protein, as well as fatty acid synthase. The extent of phosphorylation of AMP-activated protein kinase and the protein expression of fatty acid synthase were inversely regulated throughout the experimental period, whereas the extent of phosphorylation of hormone-sensitive lipase was consistently decreasing by the high-concentrate diet. Overcondition in nonpregnant, nonlactating dairy cows changed the expression of key regulator proteins of AT metabolism and circulation accompanied by impaired insulin sensitivity, which might increase the risk for metabolic disorders.


Assuntos
Bovinos/fisiologia , Metabolismo Energético/fisiologia , Metabolismo dos Lipídeos , Gordura Subcutânea/metabolismo , Proteínas Quinases Ativadas por AMP , Adiponectina/metabolismo , Animais , Composição Corporal , Dieta/veterinária , Ácidos Graxos não Esterificados/sangue , Feminino , Glucose/metabolismo , Insulina/metabolismo , Lactação/fisiologia , Leptina , Parto , Esterol Esterase/metabolismo
18.
J Thromb Haemost ; 12(6): 948-57, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24702774

RESUMO

BACKGROUND: Urokinase-type plasminogen activator (u-PA) plays a pivotal role in extracellular proteolysis and is thought to be critically involved in the modulation of angiogenesis. Interleukin (IL)-33 is a member of the IL-1 cytokine family, which is thought to act as danger signal that is released from cells after injury. IL-33 is involved in the pathogenesis of various inflammatory diseases and previously was shown to induce angiogenesis and inflammatory activation of endothelial cells. OBJECTIVE: We investigated the impact of IL-33 on u-PA in endothelial cells as a new possible function for IL-33. METHODS AND RESULTS: We could demonstrate that IL-33 upregulated u-PA mRNA expression and protein production in human coronary artery and human umbilical vein endothelial cells in a time- and concentration-dependent manner via interaction with its receptor ST2 and activation of the nuclear factor-κB pathway but independent of autocrine IL-1-induced effects. The hydroxymethylglutaryl-coenzyme A reductase inhibitor simvastatin abrogated the IL-33-induced increase in u-PA, thus providing further evidence for pleiotropic effects of statins. IL-33 induced u-PA-dependent capillary-like tube formation and vessel sprouting. In human carotid atherosclerotic plaques (n = 16), u-PA mRNA positively correlated with IL-33 mRNA expression (r = 0.780, P < 0.001). Furthermore, IL-33 and u-PA protein were detected in endothelial cells in these samples using fluorescence immunohistochemistry. CONCLUSIONS: We hypothesize that IL-33, representing a danger signal that is released after tissue damage, in addition to its role in the inflammatory activation of endothelial cells, is involved in u-PA-driven angiogenesis, a process that has been shown before to be linked to inflammation in various pathologies.


Assuntos
Indutores da Angiogênese/farmacologia , Células Endoteliais/efeitos dos fármacos , Interleucinas/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Artérias Carótidas/metabolismo , Artérias Carótidas/patologia , Doenças das Artérias Carótidas/genética , Doenças das Artérias Carótidas/metabolismo , Doenças das Artérias Carótidas/patologia , Células Cultivadas , Relação Dose-Resposta a Droga , Células Endoteliais/enzimologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/enzimologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Proteína 1 Semelhante a Receptor de Interleucina-1 , Interleucina-33 , Interleucinas/genética , Interleucinas/metabolismo , NF-kappa B/metabolismo , Placa Aterosclerótica , Interferência de RNA , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/agonistas , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sinvastatina/farmacologia , Fatores de Tempo , Transfecção , Regulação para Cima , Ativador de Plasminogênio Tipo Uroquinase/genética
19.
Hamostaseologie ; 34(1): 20-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24220294

RESUMO

Antiplatelet therapy in acute coronary syndromes is essential for preventing stent thrombosis and for reducing major adverse cardiovascular events. Treatment strategy has changed over the last years by frequent use of more active agents inhibiting the ADP mediated activation of platelets instead of clopidogrel, such as prasugrel and ticagrelor. Compared to clopidogrel these modern antiplatelet drugs showed a significant reduction of efficacy endpoints as well as an acceptable safety profile in large multicenter randomized trials (TRITON TIMI 38, PLATO). Going in with higher efficacy a generally higher bleeding risk of prasugrel could be reduced by optimizing the maintenance dose in elderly and underweight patients (TRILOGY-ACS). However even prasugrel and ticagrelor have shown a delayed onset of action in special patient populations (e.g. STEMI) suggesting that the optimal ADP inhibitor has not been found yet. Results of the CHAMPION PHOENIX trial indicate that cangrelor, an intravenous agent, might fulfill these high expectations of an ideal platelet inhibitor in the first hours of an ACS in special patient cohorts. This review summarizes the results of most important clinical studies investigating the novel P2Y12 receptor inhibiting antiplatelet drugs.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Hemorragia/induzido quimicamente , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/efeitos adversos , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , Relação Dose-Resposta a Droga , Desenho de Fármacos , Medicina Baseada em Evidências , Hemorragia/prevenção & controle , Humanos , Inibidores da Agregação Plaquetária/classificação , Antagonistas do Receptor Purinérgico P2Y/classificação , Resultado do Tratamento
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