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1.
Rev. colomb. bioét ; 17(2)dic. 2022.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1535764

ABSTRACT

Propósito/Contexto. El estudio se propone explorar la concepción de la eutanasia en los discursos de médicos y enfermeras, sus aspectos constitutivos, posturas y creencias, considerando que para avanzar en la discusión sobre la eutanasia se requiere conocer las nociones de quienes atienden al paciente al final de la vida. Metodología/Enfoque. Diseño cualitativo con análisis de contenido triangulado por las investigadoras, de 11 entrevistas en profundidad a profesionales de un hospital chileno. Resultados/Hallazgos. Se distinguen nociones etimológicas, ético-legales y operacionales de la eutanasia, además, los aspectos constitutivos (enfermedad no curativa, sufrimiento, voluntariedad y contexto médico) generan interrogantes que deben atenderse. Discusión/Conclusiones/Contribuciones. Es necesario instalar el tema en los equipos de salud y generar acuerdos socionormativos y ético-legales que sustraigan el peso de las decisiones en los individuos o los equipos profesionales.


Purpose/Background. To explore the notion of euthanasia and the positions and beliefs of doctors and nurses considering that a discussion about euthanasia requires knowing the notions of those who care for patients at the end of life. Methodology/Approach. Within a qualitative design, interviews were conducted with 11 professionals from a Chilean hospital. A content analysis was made and was triangulate by researchers. Results/Findings. Etymological, ethical-legal and operational notions of euthanasia are distinguished. Core aspects of euthanasia -non-curative disease, suffering, voluntariness and the medical context-raise questions that must be addressed. Discussion/Conclusions/Contributions. It is necessary to install the topic in the health teams and generate socio-normative ethical-legal agreements that remove the weight of the decisions in the individuals or professional teams.


Finalidade/Contexto. O estudo visa explorar a concepção da eutanásia nos discursos de médicos e enfermeiros, os seus aspectos constituintes, posições e crenças, considerando que para avançar a discussão sobre a eutanásia é necessário conhecer as noções daqueles que cuidam do doente no fim da vida. Metodologia/Aproximação. Concepção qualitativa com análise de conteúdo triangulada pelos investigadores, de 11 entrevistas em profundidade com profissionais de um hospital chileno. Resultados/Descobertas. Distinguem-se noções etimológicas, ético-legais e operacionais de eutanásia, e os aspectos constitutivos (doença não curativa, sofrimento, voluntariedade e contexto médico) levantam questões que precisam de ser abordadas. Discussão/Conclusões/Contribuições. É necessário levantar a questão nas equipas de saúde e gerar acordos sócio-normativos e ético-jurídicos que eliminem o peso da tomada de decisões de indivíduos ou equipas profissionais.

2.
Nat Genet ; 53(10): 1405-1414, 2021 10.
Article in English | MEDLINE | ID: mdl-34594042

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has affected the world radically since 2020. Spain was one of the European countries with the highest incidence during the first wave. As a part of a consortium to monitor and study the evolution of the epidemic, we sequenced 2,170 samples, diagnosed mostly before lockdown measures. Here, we identified at least 500 introductions from multiple international sources and documented the early rise of two dominant Spanish epidemic clades (SECs), probably amplified by superspreading events. Both SECs were related closely to the initial Asian variants of SARS-CoV-2 and spread widely across Spain. We inferred a substantial reduction in the effective reproductive number of both SECs due to public-health interventions (Re < 1), also reflected in the replacement of SECs by a new variant over the summer of 2020. In summary, we reveal a notable difference in the initial genetic makeup of SARS-CoV-2 in Spain compared with other European countries and show evidence to support the effectiveness of lockdown measures in controlling virus spread, even for the most successful genetic variants.


Subject(s)
COVID-19/epidemiology , COVID-19/transmission , Communicable Disease Control/organization & administration , Models, Statistical , SARS-CoV-2/genetics , COVID-19/virology , Communicable Disease Control/methods , Humans , Incidence , Phylogeny , Physical Distancing , Quarantine/methods , Quarantine/organization & administration , SARS-CoV-2/classification , SARS-CoV-2/pathogenicity , Severity of Illness Index , Spain/epidemiology
3.
Front Oncol ; 11: 610885, 2021.
Article in English | MEDLINE | ID: mdl-33928023

ABSTRACT

Ovarian cancer(OC) is a serious threat to women worldwide. Peritoneal dissemination, ascites and omental metastasis are typical features for disease progression, which occurs in a micro-environment that is rich in high-energy lipids. OC cells require high amounts of lipids for survival and growth. Not only do they import lipids from the host, they also produce lipids de novo. Inhibitors of fatty acid(FA) synthase(FASN) - the rate-limiting enzyme of endogenous FA synthesis that is overexpressed in OC - induce growth-arrest and apoptosis, rendering them promising candidates for cancer drug development. However, cancer researchers have long hypothesized that the lipid deficiency caused by FASN inhibition can be circumvented by increasing the uptake of exogenous lipids from the host, which would confer resistance to FASN inhibitors. In contrast to a very recent report in colorectal cancer, we demonstrate in OC cells (A2780, OVCAR3, SKOV3) that neither FASN inhibitors (G28UCM, Fasnall) nor FASN-specific siRNAs can stimulate a relief pathway leading to enhanced uptake of extrinsic FAs or low density lipoproteins (LDLs). Instead, we observed that the growth-arrest due to FASN inhibition or FASN knock-down was associated with significant dose- and time-dependent reduction in the uptake of fluorescently labeled FAs and LDLs. Western blotting showed that the expression of the FA receptor CD36, the LDL receptor(LDLR) and the lipid transport proteins fatty acid binding proteins 1-9 (FABP1-9) was not affected by the treatment. Next, we compared experimental blockade of endogenous lipid production with physiologic depletion of exogenous lipids. Lipid-free media, similar to FASN inhibitors, caused growth-arrest. Although lipid-depleted cells have diminished amounts of CD36, LDLR and FABPs, they can still activate a restorative pathway that causes enhanced import of fluorophore-labeled FAs and LDLs. Overall, our data show that OC cells are strictly lipid-depend and exquisitely sensitive to FASN inhibitors, providing a strong rationale for developing anti-FASN strategies for clinical use against OC.

4.
Sci Rep ; 10(1): 14877, 2020 09 10.
Article in English | MEDLINE | ID: mdl-32913236

ABSTRACT

Fatty-acid(FA)-synthase(FASN) is a druggable lipogenic oncoprotein whose blockade causes metabolic disruption. Whether drug-induced metabolic perturbation is essential for anticancer drug-action, or is just a secondary-maybe even a defence response-is still unclear. To address this, SKOV3 and OVCAR3 ovarian cancer(OC) cell lines with clear cell and serous histology, two main OC subtypes, were exposed to FASN-inhibitor G28UCM. Growth-inhibition was compared with treatment-induced cell-metabolomes, lipidomes, proteomes and kinomes. SKOV3 and OVCAR3 were equally sensitive to low-dose G28UCM, but SKOV3 was more resistant than OVCAR3 to higher concentrations. Metabolite levels generally decreased upon treatment, but individual acylcarnitines, glycerophospholipids, sphingolipids, amino-acids, biogenic amines, and monosaccharides reacted differently. Drug-induced effects on central-carbon-metabolism and oxidative-phosphorylation (OXPHOS) were essentially different in the two cell lines, since drug-naïve SKOV3 are known to prefer glycolysis, while OVCAR3 favour OXPHOS. Moreover, drug-dependent increase of desaturases and polyunsaturated-fatty-acids (PUFAs) were more pronounced in SKOV3 and appear to correlate with G28UCM-tolerance. In contrast, expression and phosphorylation of proteins that control apoptosis, FA synthesis and membrane-related processes (beta-oxidation, membrane-maintenance, transport, translation, signalling and stress-response) were concordantly affected. Overall, membrane-disruption and second-messenger-silencing were crucial for anticancer drug-action, while metabolic-rewiring was only secondary and may support high-dose-FASN-inhibitor-tolerance. These findings may guide future anti-metabolic cancer intervention.


Subject(s)
Cell Membrane/drug effects , Fatty Acid Synthase, Type I/antagonists & inhibitors , Gallic Acid/analogs & derivatives , Lipidomics/methods , Naphthalenes/pharmacology , Ovarian Neoplasms/drug therapy , Proteome/metabolism , Cell Line, Tumor , Cell Membrane/chemistry , Cell Membrane/metabolism , Cell Proliferation , Drug Resistance, Neoplasm , Fatty Acid Synthase, Type I/metabolism , Fatty Acid Synthesis Inhibitors/pharmacology , Female , Gallic Acid/pharmacology , Humans , Metabolome , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/pathology , Signal Transduction
5.
Nature ; 583(7817): 603-608, 2020 07.
Article in English | MEDLINE | ID: mdl-32641832

ABSTRACT

Astrocytes take up glucose from the bloodstream to provide energy to the brain, thereby allowing neuronal activity and behavioural responses1-5. By contrast, astrocytes are under neuronal control through specific neurotransmitter receptors5-7. However, whether the activation of astroglial receptors can directly regulate cellular glucose metabolism to eventually modulate behavioural responses is unclear. Here we show that activation of mouse astroglial type-1 cannabinoid receptors associated with mitochondrial membranes (mtCB1) hampers the metabolism of glucose and the production of lactate in the brain, resulting in altered neuronal functions and, in turn, impaired behavioural responses in social interaction assays. Specifically, activation of astroglial mtCB1 receptors reduces the phosphorylation of the mitochondrial complex I subunit NDUFS4, which decreases the stability and activity of complex I. This leads to a reduction in the generation of reactive oxygen species by astrocytes and affects the glycolytic production of lactate through the hypoxia-inducible factor 1 pathway, eventually resulting in neuronal redox stress and impairment of behavioural responses in social interaction assays. Genetic and pharmacological correction of each of these effects abolishes the effect of cannabinoid treatment on the observed behaviour. These findings suggest that mtCB1 receptor signalling can directly regulate astroglial glucose metabolism to fine-tune neuronal activity and behaviour in mice.


Subject(s)
Astrocytes/metabolism , Energy Metabolism , Glucose/metabolism , Mitochondria/metabolism , Receptor, Cannabinoid, CB1/metabolism , Animals , Astrocytes/cytology , Astrocytes/drug effects , Cannabinoid Receptor Agonists/pharmacology , Cells, Cultured , Dronabinol/pharmacology , Electron Transport Complex I/chemistry , Electron Transport Complex I/metabolism , Energy Metabolism/drug effects , Glycolysis/drug effects , Humans , Hypoxia-Inducible Factor 1/metabolism , Lactic Acid/metabolism , Male , Mice , Mitochondria/drug effects , Mitochondrial Membranes/metabolism , Oxidation-Reduction , Phosphorylation , Reactive Oxygen Species/metabolism , Receptor, Cannabinoid, CB1/agonists , Social Behavior
6.
Nat Commun ; 10(1): 5011, 2019 11 01.
Article in English | MEDLINE | ID: mdl-31676791

ABSTRACT

Upregulation of fatty acid synthase (FASN) is a common event in cancer, although its mechanistic and potential therapeutic roles are not completely understood. In this study, we establish a key role of FASN during transformation. FASN is required for eliciting the anaplerotic shift of the Krebs cycle observed in cancer cells. However, its main role is to consume acetyl-CoA, which unlocks isocitrate dehydrogenase (IDH)-dependent reductive carboxylation, producing the reductive power necessary to quench reactive oxygen species (ROS) originated during the switch from two-dimensional (2D) to three-dimensional (3D) growth (a necessary hallmark of cancer). Upregulation of FASN elicits the 2D-to-3D switch; however, FASN's synthetic product palmitate is dispensable for this process since cells satisfy their fatty acid requirements from the media. In vivo, genetic deletion or pharmacologic inhibition of FASN before oncogenic activation prevents tumor development and invasive growth. These results render FASN as a potential target for cancer prevention studies.


Subject(s)
Embryonic Stem Cells/metabolism , Fatty Acid Synthases/metabolism , Fatty Acids/metabolism , Fibroblasts/metabolism , Neoplasms, Experimental/metabolism , Animals , Cell Line , Cells, Cultured , Embryo, Mammalian/cytology , Embryonic Stem Cells/cytology , Fatty Acid Synthases/chemistry , Fatty Acid Synthases/genetics , Female , Fibroblasts/cytology , HEK293 Cells , Humans , Male , Mice, Inbred C57BL , Mice, Knockout , Mice, Nude , Mice, Transgenic , Neoplasms, Experimental/genetics , Neoplasms, Experimental/pathology , Tumor Burden/genetics
7.
Bioconjug Chem ; 29(2): 382-389, 2018 02 21.
Article in English | MEDLINE | ID: mdl-29314831

ABSTRACT

The human endogenous cannabinoid system (ECS) regulates key physiological processes and alterations in its signaling pathways, and endocannabinoid levels are associated with diseases such as neurological and neuropsychiatric conditions, cancer, pain and inflammation, obesity, and metabolic and different immune related disorders. Immune system cells express the G-protein coupled cannabinoid receptor 1 (CB1), but its functional role has not been fully understood, likely due to the lack of appropriate tools. The availability of novel tools to investigate the role of CB1 in immune regulation might contribute to identify CB1 as a potential novel therapeutic target or biomarker for many diseases. Herein, we report the development and validation of the first fluorescent small molecule probe to directly visualize and quantify CB1 in blood and tonsil immune cells by flow cytometry and confocal microscopy. We coupled the cannabinoid agonist HU210 to the fluorescent tag Alexa Fluor 488, generating a fluorescent probe with high affinity for CB1 and selectivity over CB2. We validate HU210-Alexa488 for the rapid, simultaneous, and reproducible identification of CB1 in human monocytes, T cells, and B cells by multiplexed flow cytometry. This probe is also suitable for the direct visualization of CB1 in tonsil tissues, allowing the in vivo identification of tonsil CB1-expressing T and B cells. This study provides the first fluorescent chemical tool to investigate CB1 expression and function in human blood and tonsil immune cells, which might well pave the way to unravel essential features of CB1 in different immune and ECS-related diseases.


Subject(s)
Dronabinol/analogs & derivatives , Flow Cytometry/methods , Fluorescent Dyes/chemistry , Hydrazines/chemistry , Palatine Tonsil/cytology , Receptor, Cannabinoid, CB1/analysis , Receptor, Cannabinoid, CB1/blood , B-Lymphocytes/chemistry , B-Lymphocytes/cytology , Dronabinol/chemistry , HEK293 Cells , Humans , Palatine Tonsil/chemistry , Receptor, Cannabinoid, CB1/agonists , T-Lymphocytes/chemistry , T-Lymphocytes/cytology
8.
Oncotarget ; 8(7): 11600-11613, 2017 Feb 14.
Article in English | MEDLINE | ID: mdl-28086243

ABSTRACT

Receptor-PI3K-mTORC1 signaling and fatty acid synthase (FASN)-regulated lipid biosynthesis harbor numerous drug targets and are molecularly connected. We hypothesize that unraveling the mechanisms of pathway cross-talk will be useful for designing novel co-targeting strategies for ovarian cancer (OC). The impact of receptor-PI3K-mTORC1 onto FASN is already well-characterized. However, reverse actions-from FASN towards receptor-PI3K-mTORC1-are still elusive. We show that FASN-blockade impairs receptor-PI3K-mTORC1 signaling at multiple levels. Thin-layer chromatography and MALDI-MS/MS reveals that FASN-inhibitors (C75, G28UCM) augment polyunsaturated fatty acids and diminish signaling lipids diacylglycerol (DAG) and phosphatidylinositol 3,4,5-trisphosphate (PIP3) in OC cells (SKOV3, OVCAR-3, A2780, HOC-7). Western blotting and micropatterning demonstrate that FASN-blockers impair phosphorylation/expression of EGF-receptor/ERBB/HER and decrease GRB2-EGF-receptor recruitment leading to PI3K-AKT suppression. FASN-inhibitors activate stress response-genes HIF-1α-REDD1 (RTP801/DIG2/DDIT4) and AMPKα causing mTORC1- and S6-repression. We conclude that FASN-inhibitor-mediated blockade of receptor-PI3K-mTORC1 occurs due to a number of distinct but cooperating processes. Moreover, decrease of PI3K-mTORC1 abolishes cross-repression of MEK-ERK causing ERK activation. Consequently, the MEK-inhibitor selumetinib/AZD6244, in contrast to the PI3K/mTOR-inhibitor dactolisib/NVP-BEZ235, increases growth inhibition when given together with a FASN-blocker. We are the first to provide deep insight on how FASN-inhibition blocks ERBB-PI3K-mTORC1 activity at multiple molecular levels. Moreover, our data encourage therapeutic approaches using FASN-antagonists together with MEK-ERK-inhibitors.


Subject(s)
Enzyme Inhibitors/pharmacology , Fatty Acid Synthases/antagonists & inhibitors , Multiprotein Complexes/antagonists & inhibitors , Ovarian Neoplasms/drug therapy , Phosphoinositide-3 Kinase Inhibitors , TOR Serine-Threonine Kinases/antagonists & inhibitors , Cell Line, Tumor , Cell Proliferation/physiology , Fatty Acid Synthases/metabolism , Female , Humans , Mechanistic Target of Rapamycin Complex 1 , Multiprotein Complexes/metabolism , Ovarian Neoplasms/enzymology , Ovarian Neoplasms/genetics , Ovarian Neoplasms/pathology , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction , TOR Serine-Threonine Kinases/metabolism
9.
Disabil Rehabil Assist Technol ; 12(5): 526-534, 2017 07.
Article in English | MEDLINE | ID: mdl-27052929

ABSTRACT

PURPOSE: We present a novel wheelchair posture support device (WPSD) and its clinical validation. The device was developed in order to assure correct sitting posture and to reduce the time spent by caregivers for re-positioning of hospitalized, wheelchair-bound, post-acute stroke patients. METHOD: The device was validated with 16 subjects during a period of 5 days in which use of the device was compared with regular care practice. RESULTS: The device was used for the five consecutive days in 69% of patients, while for 6% it was not suitable; 25% did not complete the 5 days for reasons unrelated to the device. Caregivers needed to re-position the patients that used the device for the full 5 days (n = 11) on an average 52% less often when using the device, as compared to regular practice. Furthermore, the device was rated as usable and functional by the caregivers while significantly reducing perception of trunk and shoulder pain in patients during its use. CONCLUSIONS: The newly designed WPSD is a valuable system for the improvement of medical assistance to wheelchair-bound post-stroke patients by reducing pain and number of re-positioning manoeuvres. The WPSD might be applicable to any group of patients who need posture control in either wheelchair or common chair with arms support. IMPLICATIONS FOR REHABILITATION Advanced supports and cushions that can be shaped to individual needs, may help assure correct sitting posture in wheelchair-bound post-acute stroke patients. Advanced supports and cushions that can be shaped to individual needs, may reduce the number of times a caregiver has to re-position a hospitalized wheelchair-bound post-acute stroke patient on overall average by 52%. Advanced personalized supports and cushions may improve sitting comfort and reduce pain complaints for post-acute hospitalized stroke patients using a wheelchair.


Subject(s)
Posture , Stroke Rehabilitation/instrumentation , Wheelchairs , Adult , Aged , Aged, 80 and over , Body Mass Index , Disabled Persons , Equipment Design , Female , Humans , Male , Middle Aged , Moving and Lifting Patients , Patient Safety , Pressure Ulcer/prevention & control , Time Factors
10.
Nature ; 539(7630): 555-559, 2016 11 24.
Article in English | MEDLINE | ID: mdl-27828947

ABSTRACT

Cellular activity in the brain depends on the high energetic support provided by mitochondria, the cell organelles which use energy sources to generate ATP. Acute cannabinoid intoxication induces amnesia in humans and animals, and the activation of type-1 cannabinoid receptors present at brain mitochondria membranes (mtCB1) can directly alter mitochondrial energetic activity. Although the pathological impact of chronic mitochondrial dysfunctions in the brain is well established, the involvement of acute modulation of mitochondrial activity in high brain functions, including learning and memory, is unknown. Here, we show that acute cannabinoid-induced memory impairment in mice requires activation of hippocampal mtCB1 receptors. Genetic exclusion of CB1 receptors from hippocampal mitochondria prevents cannabinoid-induced reduction of mitochondrial mobility, synaptic transmission and memory formation. mtCB1 receptors signal through intra-mitochondrial Gαi protein activation and consequent inhibition of soluble-adenylyl cyclase (sAC). The resulting inhibition of protein kinase A (PKA)-dependent phosphorylation of specific subunits of the mitochondrial electron transport system eventually leads to decreased cellular respiration. Hippocampal inhibition of sAC activity or manipulation of intra-mitochondrial PKA signalling or phosphorylation of the Complex I subunit NDUFS2 inhibit bioenergetic and amnesic effects of cannabinoids. Thus, the G protein-coupled mtCB1 receptors regulate memory processes via modulation of mitochondrial energy metabolism. By directly linking mitochondrial activity to memory formation, these data reveal that bioenergetic processes are primary acute regulators of cognitive functions.


Subject(s)
Cannabinoids/adverse effects , Memory Disorders/chemically induced , Memory/drug effects , Memory/physiology , Mitochondria/drug effects , Mitochondria/metabolism , Adenylyl Cyclases/metabolism , Animals , Cannabinoids/metabolism , Cell Respiration/drug effects , Cyclic AMP-Dependent Protein Kinases/metabolism , Electron Transport/drug effects , Energy Metabolism/drug effects , Female , GTP-Binding Protein alpha Subunits, Gi-Go/metabolism , Hippocampus/drug effects , Hippocampus/metabolism , Hippocampus/pathology , Male , Memory Disorders/enzymology , Memory Disorders/metabolism , Memory Disorders/pathology , Mice , Mitochondrial Membranes/drug effects , Mitochondrial Membranes/enzymology , Mitochondrial Membranes/metabolism , NADH Dehydrogenase/metabolism , Oxidative Phosphorylation/drug effects , Receptor, Cannabinoid, CB1/deficiency , Receptor, Cannabinoid, CB1/genetics , Receptor, Cannabinoid, CB1/metabolism , Signal Transduction/drug effects , Synaptic Transmission/drug effects
12.
J AOAC Int ; 99(4): 878-889, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27455929

ABSTRACT

The main known groups of mycotoxins are aflatoxins, fumonisins, ochratoxins, type A trichothecenes (T-2 toxin and HT-2 toxin), type B trichothecenes (deoxynivalenol), and zearalenones. They are harmful to humans, domestic animals, and livestock. In Europe, maximum permitted limits for aflatoxin B1 are set, and guidance levels are recommended for the other mycotoxins. This study applied biochip array technology to semiquantitative multimycotoxin screening at different levels to facilitate the verification of the compliance of feed material with acceptable safety standards. This application was developed and validated based on European Commission Decision No. 2002/657/EC. After a single generic sample-preparation method, simultaneous competitive chemiluminescent immunoassays were used and applied to the Evidence Investigator analyzer. The r and within-laboratory R values showed low overall CVs (10.6 and 11.6%, respectively). Low matrix effect and, consequently, low decision limits and detection capabilities proved the high sensitivity of the technology. The overall average recovery was 104%. Samples (n = 16) investigated within the Food Analysis Performance Assessment Scheme (FAPAS) program showed excellent correlation to assigned values. FAPAS proficiency-testing feed samples (n = 10) were within the schemes' z-score ±2 range. The authentic feed samples survey showed excellent correlation with LC-MS/MS. This application is, therefore, reliable and represents an innovative, cost-effective, and multianalytical tool for mycotoxin screening.


Subject(s)
Microarray Analysis/methods , Mycotoxins/analysis , Animal Feed/analysis , Food Contamination/analysis , Immunoassay/methods , Reproducibility of Results
13.
Int J Cancer ; 136(9): 2078-90, 2015 May 01.
Article in English | MEDLINE | ID: mdl-25302649

ABSTRACT

Ovarian cancer (OC) is caused by genetic aberrations in networks that control growth and survival. Importantly, aberrant cancer metabolism interacts with oncogenic signaling providing additional drug targets. Tumors overexpress the lipogenic enzyme fatty acid synthase (FASN) and are inhibited by FASN blockers, whereas normal cells are FASN-negative and FASN-inhibitor-resistant. Here, we demonstrate that this holds true when ovarian/oviductal cells reside in their autochthonous tissues, whereas in culture they express FASN and are FASN-inhibitor-sensitive. Upon subculture, nonmalignant cells cease growth, express senescence-associated ß-galactosidase, lose FASN and become FASN-inhibitor-resistant. Immortalized ovarian/oviductal epithelial cell lines­although resisting senescence­reveal distinct growth activities, which correlate with FASN levels and FASN drug sensitivities. Accordingly, ectopic FASN stimulates growth in these cells. Moreover, FASN levels and lipogenic activities affect cellular lipid composition as demonstrated by thin-layer chromatography. Correlation between proliferation and FASN levels was finally evaluated in cancer cells such as HOC-7, which contain subclones with variable differentiation/senescence and corresponding FASN expression/FASN drug sensitivity. Interestingly, senescent phenotypes can be induced in parental HOC-7 by differentiating agents. In OC cells, FASN drugs induce cell cycle blockade in S and/or G2/M and stimulate apoptosis, whereas in normal cells they only cause cell cycle deceleration without apoptosis. Thus, normal cells, although growth-inhibited, may survive and recover from FASN blockade, whereas malignant cells get extinguished. FASN expression and FASN drug sensitivity are directly linked to cell growth and correlate with transformation/differentiation/senescence only indirectly. FASN is therefore a metabolic marker of cell proliferation rather than a marker of malignancy and is a useful target for future drug development.


Subject(s)
Biomarkers, Tumor/genetics , Cell Proliferation/genetics , Fatty Acid Synthase, Type I/genetics , Ovarian Neoplasms/genetics , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Apoptosis/genetics , Cell Cycle , Cell Line , Cell Line, Tumor , Epithelial Cells/drug effects , Female , Humans , Ovarian Neoplasms/drug therapy
15.
BMC Microbiol ; 12: 68, 2012 May 08.
Article in English | MEDLINE | ID: mdl-22568957

ABSTRACT

BACKGROUND: Procalcitonin (PCT) is a polypeptide with several cationic aminoacids in its chemical structure and it is a well known marker of sepsis. It is now emerging that PCT might exhibit some anti-inflammatory effects. The present study, based on the evaluation of the in vitro interaction between PCT and bacterial lipopolisaccharide (LPS), reports new data supporting the interesting and potentially useful anti-inflammatory activity of PCT. RESULTS: PCT significantly decreased (p < 0.05) the limulus amoebocyte lysate (LAL) assay reactivity of LPS from both Salmonella typhimurium (rough chemotype) and Escherichia coli (smooth chemotype). Subsequently, the in vitro effects of PCT on LPS-induced cytokine release were studied in human peripheral blood mononuclear cells (PBMC). When LPS was pre-incubated for 30 minutes with different concentrations of PCT, the release of interleukin-10 (IL-10) and tumor necrosis factor alpha (TNFα) by PBMC decreased in a concentration-dependent manner after 24 hours for IL-10 and 4 hours for TNFα. The release of monocyte chemotactic protein-1 (MCP-1) exhibited a drastic reduction at 4 hours for all the PCT concentrations assessed, whereas such decrease was concentration-dependent after 24 hours. CONCLUSIONS: This study provides the first evidence of the capability of PCT to directly neutralize bacterial LPS, thus leading to a reduction of its major inflammatory mediators.


Subject(s)
Calcitonin/metabolism , Cytokines/immunology , Cytokines/metabolism , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/immunology , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/immunology , Protein Precursors/metabolism , Calcitonin Gene-Related Peptide , Cells, Cultured , Escherichia coli/chemistry , Escherichia coli/immunology , Humans , Limulus Test , Salmonella typhimurium/chemistry , Salmonella typhimurium/immunology
16.
18.
Nat Neurosci ; 15(4): 558-64, 2012 Mar 04.
Article in English | MEDLINE | ID: mdl-22388959

ABSTRACT

The mammalian brain is one of the organs with the highest energy demands, and mitochondria are key determinants of its functions. Here we show that the type-1 cannabinoid receptor (CB(1)) is present at the membranes of mouse neuronal mitochondria (mtCB(1)), where it directly controls cellular respiration and energy production. Through activation of mtCB(1) receptors, exogenous cannabinoids and in situ endocannabinoids decreased cyclic AMP concentration, protein kinase A activity, complex I enzymatic activity and respiration in neuronal mitochondria. In addition, intracellular CB(1) receptors and mitochondrial mechanisms contributed to endocannabinoid-dependent depolarization-induced suppression of inhibition in the hippocampus. Thus, mtCB(1) receptors directly modulate neuronal energy metabolism, revealing a new mechanism of action of G protein-coupled receptor signaling in the brain.


Subject(s)
Energy Metabolism/physiology , Mitochondria/physiology , Mitochondrial Membranes/physiology , Neurons/metabolism , Receptor, Cannabinoid, CB1/physiology , Animals , Animals, Newborn , CHO Cells , Cells, Cultured , Cricetinae , Cricetulus , Female , Male , Mice , Mice, Knockout , Mitochondria/metabolism , Mitochondrial Membranes/metabolism , Neurons/physiology , Rats , Receptor, Cannabinoid, CB1/metabolism
19.
Breast Cancer Res ; 13(6): R131, 2011.
Article in English | MEDLINE | ID: mdl-22177475

ABSTRACT

INTRODUCTION: Inhibiting the enzyme Fatty Acid Synthase (FASN) leads to apoptosis of breast carcinoma cells, and this is linked to human epidermal growth factor receptor 2 (HER2) signaling pathways in models of simultaneous expression of FASN and HER2. METHODS: In a xenograft model of breast carcinoma cells that are FASN+ and HER2+, we have characterised the anticancer activity and the toxicity profile of G28UCM, the lead compound of a novel family of synthetic FASN inhibitors. In vitro, we analysed the cellular and molecular interactions of combining G28UCM with anti-HER drugs. Finally, we tested the cytotoxic ability of G28UCM on breast cancer cells resistant to trastuzumab or lapatinib, that we developed in our laboratory. RESULTS: In vivo, G28UCM reduced the size of 5 out of 14 established xenografts. In the responding tumours, we observed inhibition of FASN activity, cleavage of poly-ADPribose polymerase (PARP) and a decrease of p-HER2, p- protein kinase B (AKT) and p-ERK1/2, which were not observed in the nonresponding tumours. In the G28UCM-treated animals, no significant toxicities occurred, and weight loss was not observed. In vitro, G28UCM showed marked synergistic interactions with trastuzumab, lapatinib, erlotinib or gefitinib (but not with cetuximab), which correlated with increases in apoptosis and with decreases in the activation of HER2, extracellular signal-regulated kinase (ERK)1/2 and AKT. In trastuzumab-resistant and in lapatinib-resistant breast cancer cells, in which trastuzumab and lapatinib were not effective, G28UCM retained the anticancer activity observed in the parental cells. CONCLUSIONS: G28UCM inhibits fatty acid synthase (FASN) activity and the growth of breast carcinoma xenografts in vivo, and is active in cells with acquired resistance to anti-HER2 drugs, which make it a candidate for further pre-clinical development.


Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/metabolism , Enzyme Inhibitors/pharmacology , Fatty Acid Synthases/antagonists & inhibitors , Naphthalenes/pharmacology , Receptor, ErbB-2/metabolism , Animals , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/toxicity , Apoptosis/drug effects , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Resistance, Neoplasm , Drug Synergism , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/toxicity , Female , Gallic Acid/administration & dosage , Gallic Acid/pharmacology , Gallic Acid/toxicity , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Naphthalenes/administration & dosage , Naphthalenes/toxicity , Protein Kinase Inhibitors/pharmacology , Receptor, ErbB-2/antagonists & inhibitors , Receptor, ErbB-2/genetics , Signal Transduction/drug effects , Xenograft Model Antitumor Assays
20.
Clin Cancer Res ; 15(24): 7608-7615, 2009 Dec 15.
Article in English | MEDLINE | ID: mdl-20008854

ABSTRACT

PURPOSE: Fatty acid synthase (FASN) is overexpressed in human breast carcinoma. The natural polyphenol (-)-epigallocatechin-3-gallate blocks in vitro FASN activity and leads to apoptosis in breast cancer cells without any effects on carnitine palmitoyltransferase-1 (CPT-1) activity, and in vivo, does not decrease body weight. We synthesized a panel of new polyphenolic compounds and tested their effects on breast cancer models. EXPERIMENTAL DESIGN: We evaluated the in vitro effects of the compounds on breast cancer cell growth (SK-Br3, MCF-7, and MDA-MB-231), apoptosis [as assessed by cleavage of poly(ADP-ribose) polymerase], cell signaling (HER2, ERK1/2, and AKT), and fatty acid metabolism enzymes (FASN and CPT-1). In vivo, we have evaluated their antitumor activity and their effect on body weight in a mice model of BT474 breast cancer cells. RESULTS: Two compounds potently inhibited FASN activity and showed high cytotoxicity. Moreover, the compounds induced apoptosis and caused a marked decrease in the active forms of HER2, AKT, and ERK1/2 proteins. Interestingly, the compounds did not stimulate CPT-1 activity in vitro. We show evidence that one of the FASN inhibitors blocked the growth of BT474 breast cancer xenografts and did not induce weight loss in vivo. CONCLUSIONS: The synthesized polyphenolic compounds represent a novel class of FASN inhibitors, with in vitro and in vivo anticancer activity, that do not exhibit cross-activation of beta-oxidation and do not induce weight loss in animals. One of the compounds blocked the growth of breast cancer xenografts. These FASN inhibitors may represent new agents for breast cancer treatment. (Clin Cancer Res 2009;15(24):7608-15).

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