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1.
Palliat Med ; 36(3): 540-548, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35184630

RESUMO

BACKGROUND: Parenteral nutrition is controversial in patients with advanced cancer. Nevertheless, this treatment is common practice near the end of life. AIM: We aimed to identify factors which were associated with the outcome of patients on parenteral nutrition at an academic tertiary palliative care unit. DESIGN: In this retrospective cohort study patients were assigned to two groups according to parenteral nutrition treatment. Inferential statistics were used to assess whether the dynamics of laboratory variables over 2 weeks of parenteral nutrition were associated with survival. SETTING/PARTICIPANTS: Patients admitted to the Department of Palliative Medicine at the Medical University of Vienna between 2016 and 2018 were included in this study. RESULTS: Of 443 patients, 113 patients received parenteral nutrition. Patients had a lower body mass index, lower levels of bilirubin, γ-glutamyltransferase, alkaline phosphatase, and were of younger age compared to patients which did not receive parenteral nutrition. No difference in survival as measured from admission to death was found when comparing the two groups. Levels for γ-glutamyltransferase, alkaline phosphatase, and C-reactive protein significantly increased during 2 weeks of parenteral nutrition. Among patients with parenteral nutrition, an increase in C-reactive protein or white blood cell count levels was associated with lower survival. CONCLUSION: Patients who responded with an increase of C-reactive protein or white blood cell count during 2 weeks after reinitiation or start of parenteral nutrition had a worse survival. Our findings might support clinicians and patients in their decision to forgo parenteral nutrition in a palliative care setting.


Assuntos
Proteína C-Reativa , Neoplasias , Humanos , Contagem de Leucócitos , Neoplasias/complicações , Neoplasias/terapia , Cuidados Paliativos , Nutrição Parenteral , Prognóstico , Estudos Retrospectivos
2.
Food Funct ; 12(21): 10432-10442, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34617546

RESUMO

Decreasing circulating low-density lipoprotein (LDL) cholesterol levels leads to decreased risk of cardiovascular diseases. Natural compounds are capable of lowering LDL-cholesterol even on top of lifestyle modification or medication. To identify novel plant-derived compounds to lower plasma LDL cholesterol levels, we performed high-content screening based on the transcriptional activation of the promoter of the LDL receptor (LDLR). The identified hits were thoroughly validated in human hepatic cell lines in terms of increasing LDLR mRNA and protein levels, lowering cellular cholesterol levels and increasing cellular LDL uptake. By means of this incremental validation process in vitro, aqueous extracts prepared from leaves of lingonberries (Vaccinium vitis-idaea) as well as blackberries (Rubus fruticosus) were found to have effects comparable to lovastatin, a prototypic cholesterol-lowering drug. When applied in vivo in mice, both extracts induced subtle increases in hepatic LDLR expression. In addition, a significant increase in high-density lipoprotein (HDL) cholesterol was observed. Taken together, aqueous extracts from lingonberry or blackberry leaves were identified and characterized as strong candidates to provide cardiovascular protection.


Assuntos
Anticolesterolemiantes/farmacologia , Colesterol/metabolismo , Extratos Vegetais/farmacologia , Folhas de Planta/metabolismo , Rubus/metabolismo , Vaccinium vitis-Idaea/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais
3.
Int J Cancer ; 148(6): 1452-1461, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32949150

RESUMO

The predictive effect of circulating tumor DNA (ctDNA) in colorectal cancer (CRC) treatment is still highly discussed. The primary objective of our study was to investigate a possible prognostic/predictive value of ctDNA under regorafenib treatment. This prospective multicenter translational biomarker phase II pilot study enrolled 30 metastatic CRC patients (67% men, 33% women) treated with regorafenib. ctDNA was assessed in plasma before treatment start and at defined time points during administration. Measurement of tumor fraction as well as mutation and copy number analysis of CRC driver genes were performed by next-generation sequencing approaches. Multivariate analyses for survival and treatment efficacy were adjusted to age, gender and Eastern Cooperative Oncology Group. Disease control rate was 30%. Median tumor fraction at baseline was 18.5% (0-49.9). Mutations in CRC driver genes or genes involved in angiogenesis were identified in 25 patients (83.3%). KRAS mutations were detected in 13 of 14 KRAS-positive tumors; in three patients without KRAS mutation in the respective tumors, acquired mutations as a consequence of prior anti-EGFR treatment were detected. In a subset of patients, novel occurring mutations or focal amplifications were detected. A tumor fraction of 5% and higher at baseline was significantly associated with a decreased OS (P = .022; hazard ratio 3.110 (95% confidence interval: 1.2-8.2). ctDNA is detectable in a high proportion of mCRC patients. Higher ctDNA levels are associated with survival among regorafenib treatment. Moreover, our data highlight the benefit of a combined evaluation of mutations and somatic copy number alterations in advanced cancer patients.


Assuntos
Biomarcadores Tumorais/sangue , DNA Tumoral Circulante/sangue , Neoplasias Colorretais/sangue , Compostos de Fenilureia/uso terapêutico , Piridinas/uso terapêutico , Adulto , Idoso , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Feminino , Humanos , Biópsia Líquida , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Resultado do Tratamento
4.
Dev Dyn ; 249(2): 222-236, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31691430

RESUMO

BACKGROUND: The mammalian yolk sac provides nutrients for the growing fetus during critical early developmental processes such as neural tube closure, which precedes the functional maturation of the placenta. In contrast, oviparous species such as the chicken rely solely on the yolk sac for transfer of nutrients from the yolk to the developing embryo. However, the molecular mechanisms that provide the yolk sac with nutrient transfer competence remain poorly understood. RESULTS: We demonstrate that the chicken endodermal epithelial cells (EEC), which are in close contact with the yolk, gain their nutrient-transport competence by a paracrine crosstalk with the blood-vessel forming mesodermal cell layer. Bone morphogenetic proteins (BMP) 4 and 7 produced by ectodermal and mesodermal cell layers likely initiate a differentiation program of EECs during the transition from the area vitellina to the area vasculosa. BMPs, by inducing SMAD signaling, promote the up-regulation of endocytic receptor expression and thereby provide the EECs with the molecular machinery to produce triglyceride-rich lipoprotein particles. CONCLUSION: This paracrine signaling cascade may constitute the basis for the EEC-mediated mechanism underlying the efficient uptake, degradation, resynthesis, and transfer of yolk-derived nutrients into the embryonic circulation, which assures proper energy supply and development of the growing fetus.


Assuntos
Endoderma/citologia , Células Epiteliais/metabolismo , Lipoproteínas/metabolismo , Animais , Proteína Morfogenética Óssea 4/metabolismo , Proteína Morfogenética Óssea 7/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Embrião de Galinha , Galinhas , Saco Vitelino
5.
J Lipid Res ; 60(11): 1922-1934, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31530576

RESUMO

During pregnancy, extravillous trophoblasts (EVTs) invade the maternal decidua and remodel the local vasculature to establish blood supply for the growing fetus. Compromised EVT function has been linked to aberrant pregnancy associated with maternal and fetal morbidity and mortality. However, metabolic features of this invasive trophoblast subtype are largely unknown. Using primary human trophoblasts isolated from first trimester placental tissues, we show that cellular cholesterol homeostasis is differentially regulated in EVTs compared with villous cytotrophoblasts. Utilizing RNA-sequencing, gene set-enrichment analysis, and functional validation, we provide evidence that EVTs display increased levels of free and esterified cholesterol. Accordingly, EVTs are characterized by increased expression of the HDL-receptor, scavenger receptor class B type I, and reduced expression of the LXR and its target genes. We further reveal that EVTs express elevated levels of hydroxy-delta-5-steroid dehydrogenase 3 beta- and steroid delta-isomerase 1 (HSD3B1) (a rate-limiting enzyme in progesterone synthesis) and are capable of secreting progesterone. Increasing cholesterol export by LXR activation reduced progesterone secretion in an ABCA1-dependent manner. Importantly, HSD3B1 expression was decreased in EVTs of idiopathic recurrent spontaneous abortions, pointing toward compromised progesterone metabolism in EVTs of early miscarriages. Here, we provide insights into the regulation of cholesterol and progesterone metabolism in trophoblastic subtypes and its putative relevance in human miscarriage.


Assuntos
Aborto Habitual/metabolismo , Colesterol/metabolismo , Progesterona/metabolismo , Trofoblastos/metabolismo , Biologia Computacional , Feminino , Homeostase , Humanos , Gravidez , Análise de Sequência de RNA
6.
Cancer Res ; 78(12): 3220-3232, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29674477

RESUMO

Intrinsic and adaptive resistance hampers the success of antiangiogenic therapies (AAT), especially in breast cancer where this treatment modality has proven largely ineffective. Therefore, novel strategies to improve the efficacy of AAT are warranted. Solid tumors such as breast cancer are characterized by a high infiltration of myeloid-derived suppressor cells (MDSC), which are key drivers of resistance to AAT. Therefore, we hypothesized that all-trans retinoic acid (ATRA), which induces differentiation of MDSC into mature cells, could improve the therapeutic effect of AAT. ATRA increased the efficacy of anti-VEGFR2 antibodies alone and in combination with chemotherapy in preclinical breast cancer models. ATRA reverted the anti-VEGFR2-induced accumulation of intratumoral MDSC, alleviated hypoxia, and counteracted the disorganization of tumor microvessels. Mechanistic studies indicate that ATRA treatment blocked the AAT-induced expansion of MDSC secreting high levels of vessel-destabilizing S100A8. Thus, concomitant treatment with ATRA holds the potential to improve AAT in breast cancer and possibly other tumor types.Significance: Increasing the therapeutic efficiency of antiangiogenic drugs by reducing resistance-conferring myeloid-derived suppressor cells might improve breast cancer treatment.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/12/3220/F1.large.jpg Cancer Res; 78(12); 3220-32. ©2018 AACR.


Assuntos
Inibidores da Angiogênese/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Células Supressoras Mieloides/efeitos dos fármacos , Tretinoína/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Calgranulina A/metabolismo , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/imunologia , Linhagem Celular Tumoral/transplante , Técnicas de Cocultura , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Células Supressoras Mieloides/fisiologia , Estabilidade Proteica/efeitos dos fármacos , Resultado do Tratamento , Tretinoína/uso terapêutico , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores
7.
Haematologica ; 103(6): 939-948, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29567778

RESUMO

Although inhibitors of bromodomain and extra terminal domain (BET) proteins show promising clinical activity in different hematologic malignancies, a systematic analysis of the consequences of pharmacological BET inhibition on healthy hematopoietic (stem) cells is urgently needed. We found that JQ1 treatment decreases the numbers of pre-, immature and mature B cells while numbers of early pro-B cells remain constant. In addition, JQ1 treatment increases apoptosis in T cells, all together leading to reduced cellularity in thymus, bone marrow and spleen. Furthermore, JQ1 induces proliferation of long-term hematopoietic stem cells, thereby increasing stem cell numbers. Due to increased numbers, JQ1-treated hematopoietic stem cells engrafted better after stem cell transplantation and repopulated the hematopoietic system significantly faster after sublethal myeloablation. As quantity and functionality of hematopoietic stem cells determine the duration of life-threatening myelosuppression, BET inhibition might benefit patients in myelosuppressive conditions.


Assuntos
Antineoplásicos/farmacologia , Azepinas/farmacologia , Autorrenovação Celular/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Proteínas/antagonistas & inibidores , Triazóis/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linfócitos B/citologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Biomarcadores , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência de Enxerto/efeitos dos fármacos , Hematopoese , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/efeitos da radiação , Imunofenotipagem , Camundongos , Fenótipo , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo
8.
Biochim Biophys Acta ; 1861(9 Pt A): 1132-1141, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27344248

RESUMO

Acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1) is a key enzyme in triacylglycerol (TG) biosynthesis. Here we show that genetic deficiency and pharmacological inhibition of DGAT1 in mice alters cholesterol metabolism. Cholesterol absorption, as assessed by acute cholesterol uptake, was significantly decreased in the small intestine and liver upon DGAT1 deficiency/inhibition. Ablation of DGAT1 in the intestine (I-DGAT1(-/-)) alone is sufficient to cause these effects. Consequences of I-DGAT1 deficiency phenocopy findings in whole-body DGAT1(-/-) and DGAT1 inhibitor-treated mice. We show that deficiency/inhibition of DGAT1 affects cholesterol metabolism via reduced chylomicron size and increased trans-intestinal cholesterol excretion. These effects are independent of cholesterol uptake at the apical surface of enterocytes but mediated through altered dietary fatty acid metabolism. Our findings provide insight into a novel role of DGAT1 and identify a pathway by which intestinal DGAT1 deficiency affects whole-body cholesterol homeostasis in mice. Targeting intestinal DGAT1 may represent a novel approach for treating hypercholesterolemia.


Assuntos
Colesterol/metabolismo , Diacilglicerol O-Aciltransferase/genética , Hipercolesterolemia/tratamento farmacológico , Metabolismo dos Lipídeos/genética , Triglicerídeos/metabolismo , Animais , Diacilglicerol O-Aciltransferase/deficiência , Diacilglicerol O-Aciltransferase/metabolismo , Gorduras na Dieta , Ácidos Graxos/metabolismo , Hipercolesterolemia/metabolismo , Absorção Intestinal/genética , Lipogênese/genética , Fígado/metabolismo , Camundongos
9.
J Biol Chem ; 288(2): 1088-98, 2013 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-23209291

RESUMO

During chicken yolk sac (YS) growth, mesodermal cells in the area vasculosa follow the migrating endodermal epithelial cell (EEC) layer in the area vitellina. Ultimately, these cells form the vascularized YS that functions in nutrient transfer to the embryo. How and when EECs, with their apical aspect directly contacting the oocytic yolk, acquire the ability to take up yolk macromolecules during the vitellina-to-vasculosa transition has not been investigated. In addressing these questions, we found that with progressive vascularization, the expression level in EECs of the nutrient receptor triad, LRP2-cubilin-amnionless, changes significantly. The receptor complex, competent for uptake of yolk proteins, is produced by EECs in the area vasculosa but not in the area vitellina. Yolk components endocytosed by LRP2-cubilin-amnionless, preformed and newly formed lipid droplets, and yolk-derived very low density lipoprotein, shown to be efficiently endocytosed and lysosomally processed by EECs, probably provide substrates for resynthesis and secretion of nutrients, such as lipoproteins. In fact, as directly demonstrated by pulse-chase experiments, EECs in the vascularized, but not in the avascular, region efficiently produce and secrete lipoproteins containing apolipoprotein A-I (apoA-I), apoB, and/or apoA-V. In contrast, perilipin 2, a lipid droplet-stabilizing protein, is produced exclusively by the EECs of the area vitellina. These data suggest a differentiation process that orchestrates the vascularization of the developing YS with the induction of yolk uptake and lipoprotein secretion by EECs to ensure embryo nutrition.


Assuntos
Diferenciação Celular , Endoderma/química , Saco Vitelino , Animais , Sequência de Bases , Transporte Biológico , Western Blotting , Embrião de Galinha , Primers do DNA , Células Epiteliais/citologia , Hibridização In Situ , Reação em Cadeia da Polimerase
10.
Biochem Biophys Res Commun ; 406(2): 257-61, 2011 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-21316342

RESUMO

In laying hens, massive hepatic mobilization of fatty acids is required for the synthesis of oocyte-targeted very-low density lipoproteins (VLDL). The current study aims at identification of enzymes that hydrolyze hepatic acylglycerol stores regulated in a fashion compatible with supporting enhanced VLDL synthesis. We show that unlike mammals, chickens express adipose triglyceride lipase (ATGL) also in liver, where it is upregulated by fasting, while the enzyme patatin-like phospholipase domain-containing lipase 3 (PNPLA3) is suppressed. For the first time in any system, we show that hepatic arylacetamide deacetylase (AADA) is upregulated by fasting, and that its affinity for an insoluble carboxylester substrate is compatible with an in-vivo function similar to that of ATGL. Unknown heretofore, hepatic expression of chicken AADA is estrogen-responsive, and is induced to the same degree as the stimulation of VLDL-production by estrogen. These observations support roles of chicken ATGL, PNPLA3, and AADA in acylglycerol metabolism related to the high rates of VLDL synthesis that are essential for reproduction.


Assuntos
Amidoidrolases/metabolismo , Galinhas/metabolismo , Glicerídeos/metabolismo , Lipase/metabolismo , Fígado/enzimologia , Proteínas de Membrana/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , Estrogênios/farmacologia , Feminino , Lipoproteínas VLDL/biossíntese , Fígado/efeitos dos fármacos , Masculino , Dados de Sequência Molecular
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