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INTRODUCTION: Perioperative music can have beneficial effects on postoperative pain, anxiety, opioid requirement, and the physiological stress response to surgery. The aim was to assess the effects of intraoperative music during general anesthesia in patients undergoing surgery for esophagogastric cancer. MATERIALS AND METHODS: The IMPROMPTU study was a double-blind, placebo-controlled, randomized multicenter trial. Adult patients undergoing surgery for stage II-III esophagogastric cancer were eligible. Exclusion criteria were a hearing impairment, insufficient Dutch language knowledge, corticosteroids use, or objection to hearing unknown music. Patients wore active noise-cancelling headphones intraoperatively with preselected instrumental classical music (intervention) or no music (control). Computerized randomization with centralized allocation, stratified according to surgical procedure using variable block sizes, was employed. Primary endpoint was postoperative pain on the first postoperative day. Secondary endpoints were postoperative pain during the first postoperative week, postoperative opioid requirement, intraoperative medication requirement, the stress response to surgery, postoperative complication rate, length of stay, and mortality, with follow-up lasting 30 d. RESULTS: From November 2018 to September 2020, 145 patients were assessed and 83 randomized. Seventy patients (music n = 31, control n = 39) were analyzed. Median age was 70 [IQR 63-70], and 48 patients (69%) were male. Music did not reduce postoperative pain (numeric rating scale 1.8 (SD0.94) versus 2.0 (1.0), mean difference -0.28 [95% CI -0.76-0.19], P = 0.236). No statistically significant differences were seen in medication requirement, stress response, complication rate, or length of stay. CONCLUSIONS: Intraoperative, preselected, classical music during esophagogastric cancer surgery did not significantly improve postoperative outcome and recovery when compared to no music using noise-cancelling headphones.
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Neoplasias Esofágicas , Música , Neoplasias Gástricas , Adulto , Humanos , Masculino , Idoso , Feminino , Analgésicos Opioides/uso terapêutico , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Gástricas/tratamento farmacológico , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Método Duplo-CegoRESUMO
OBJECTIVES: Human scalp hair is an easily available but complex matrix for determination of cortisone and cortisol, and has been shown to reflect long-term glucocorticoid exposure. Hair glucocorticoid analysis has been used to detect hypo- and hypercortisolism. In this study, we describe the development and validation of a LC-MS/MS method for quantification of cortisone and cortisol in human scalp hair, and provide a novel approach for analysis and interpretation of the results. METHODS: Improved sample preparation using pulverization and solid phase extraction allowed for low sample volumes (10â¯mg). Baseline chromatographic separation without matrix interference was achieved by reversed phase chromatography and MRM measurement in negative ion mode. Run-to-run time was 8â¯min. Mixed model analyses were performed to create individual patterns of cortisone and cortisol concentrations. RESULTS: Matrix matched calibration curves showed excellent linearity up to 100â¯pg (analyte)/mg (hair) for both cortisone and cortisol (R2>0.995). LLOQ was 1.5 and 1.0â¯pg/mg for cortisone and cortisol, respectively. Matrix effect was negligible for hair color (recoveries 95-105â¯%). Cortisone and cortisol concentrations decreased from proximal to distal hair segments, following a predictable, but subject-specific pattern, with less individual variation for cortisone than for cortisol. CONCLUSIONS: This improved LC-MS/MS method is able to accurately quantify cortisone and cortisol in human hair with minimum matrix interference. This new way of data analysis and interpretation including individual patterns of cortisone and cortisol will be of help with detection of pathological concentrations in both the high - and the low ranges of glucocorticoids.
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Cortisona , Hidrocortisona , Humanos , Cortisona/análise , Cromatografia Líquida/métodos , Glucocorticoides , Couro Cabeludo/química , Espectrometria de Massas em Tandem/métodos , Cabelo/químicaRESUMO
OBJECTIVES: Interference from isomeric steroids is a potential cause of disparity between mass spectrometry-based 17-hydroxyprogesterone (17OHP) results. We aimed to assess the proficiency of mass spectrometry laboratories to report 17OHP in the presence of known isomeric steroids. METHODS: A series of five samples were prepared using a previously demonstrated commutable approach. These samples included a control (spiked to 15.0â¯nmol/L 17OHP) and four challenge samples further enriched with equimolar concentrations of 17OHP isomers (11α-hydroxyprogesterone, 11ß-hydroxyprogesterone, 16α-hydroxyprogesterone or 21-hydroxyprogesterone). These samples were distributed to 38 participating laboratories that reported serum 17OHP results using mass spectrometry in two external quality assurance programs. The result for each challenge sample was compared to the control sample submitted by each participant. RESULTS: Twenty-six laboratories (68â¯% of distribution) across three continents returned results. Twenty-five laboratories used liquid chromatography-tandem mass spectrometry (LC-MS/MS), and one used gas chromatography-tandem mass spectrometry to measure 17OHP. The all-method median of the control sample was 14.3â¯nmol/L, ranging from 12.4 to 17.6â¯nmol/L. One laboratory had results that approached the lower limit of tolerance (minus 17.7â¯% of the control sample), suggesting the isomeric steroid caused an irregular result. CONCLUSIONS: Most participating laboratories demonstrated their ability to reliably measure 17OHP in the presence of the four clinically relevant isomeric steroids. The performance of the 12 (32â¯%) laboratories that did not engage in this activity remains unclear. We recommend that all laboratories offering LC-MS/MS analysis of 17OHP in serum, plasma, or dried bloodspots determine that the isomeric steroids are appropriately separated.
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Hidroxiprogesteronas , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Sensibilidade e Especificidade , 17-alfa-Hidroxiprogesterona , EsteroidesRESUMO
OBJECTIVE: Individuals with 45,X/46,XY or 46,XY gonadal dysgenesis are at increased risk of germ cell malignancies. Therefore, prophylactic bilateral gonadectomy is advised in girls and considered in boys with atypical genitalia for undescended, macroscopically abnormal gonads. However, severely dysgenetic gonads may not contain germ cells rendering gonadectomy unnecessary. Therefore, we investigate if undetectable preoperative serum anti-Müllerian hormone (AMH) and inhibin B can predict the absence of germ cells, (pre)malignant or otherwise. DESIGN, PATIENTS AND MEASUREMENTS: Individuals who had undergone bilateral gonadal biopsy and/or gonadectomy because of suspected gonadal dysgenesis in 1999-2019 were included in this retrospective study if preoperative AMH and/or inhibin B were available. Histological material was reviewed by an experienced pathologist. Haematoxylin and eosin and immunohistochemical stainings for SOX9, OCT4, TSPY and SCF (KITL) were used. RESULTS: Thirteen males and 16 females were included, 20 with 46,XY and 9 with 45,X/46,XY DSD. Three females had dysgerminoma alongside gonadoblastoma; two gonadoblastoma, one germ cell neoplasia in situ (GCNIS) and three males had pre-GCNIS and/or pre-gonadoblastoma. Gonadoblastoma and/or dysgerminoma were present in 3/11 individuals with undetectable AMH and inhibin B, one of whom also had non-(pre)malignant germ cells. Of the other 18, in whom AMH and/or inhibin B were detectable, only one had no germ cells. CONCLUSIONS: Undetectable serum AMH and inhibin B cannot reliably predict the absence of germ cells and germ cell tumours in individuals with 45,X/46,XY or 46,XY gonadal dysgenesis. This information should help in counselling about prophylactic gonadectomy, taking into account both the germ cell cancer risk and potential for gonadal function.
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Disgerminoma , Disgenesia Gonadal 46 XY , Disgenesia Gonadal , Gonadoblastoma , Neoplasias Embrionárias de Células Germinativas , Neoplasias Ovarianas , Masculino , Feminino , Humanos , Gonadoblastoma/genética , Gonadoblastoma/cirurgia , Hormônio Antimülleriano , Disgerminoma/cirurgia , Estudos RetrospectivosRESUMO
OBJECTIVES: Predicting the patients' tolerance to enteral nutrition (EN) would help clinicians optimize individual nutritional intake. This study investigated the course of several gastrointestinal (GI) biomarkers and their association with EN advancement (ENA) longitudinally during pediatric intensive care unit (PICU) admission. METHODS: This is a secondary analysis of the Early versus Late Parenteral Nutrition in the Pediatric Intensive Care Unit randomized controlled trial. EN was started early and increased gradually. The cholecystokinin (CCK), leptin, glucagon, intestinal fatty acid-binding protein 2 (I-FABP2), and citrulline plasma concentrations were measured upon PICU admission, day 3 and day 5. ENA was defined as kcal EN provided as % of predicted resting energy expenditure. The course of the biomarkers and ENA was examined in patients with samples on all time points using Friedman and Wilcoxon signed-rank tests. The association of ENA with the biomarkers was examined using a 2-part mixed-effects model with data of the complete population, adjusted for possible confounders. RESULTS: For 172 patients, median age 8.6 years (first quartile; third quartile: 4.2; 13.4), samples were available, of which 55 had samples on all time points. The median ENA was 0 (0; 0) on admission, 14.5 (0.0; 43.8) on day 3, and 28.0 (7.6; 94.8) on day 5. During PICU stay, CCK and I-FABP2 concentrations decreased significantly, whereas glucagon concentrations increased significantly, and leptin and citrulline remained stable. None of the biomarkers was longitudinally associated with ENA. CONCLUSIONS: Based on the current evidence, CCK, leptin, glucagon, I-FABP2, and citrulline appear to have no added value in predicting ENA in the first 5 days of pediatric critical illness.
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Estado Terminal , Leptina , Criança , Humanos , Estado Terminal/terapia , Citrulina , Glucagon , Unidades de Terapia Intensiva Pediátrica , BiomarcadoresRESUMO
OBJECTIVES: International guidelines recommend fixed cut-off values for thyroglobulin (Tg). These cut-offs do not take potential assay differences into account. This study aimed to evaluate if different assays for Tg and Tg antibodies (TgAb) affect management guidance for differentiated thyroid cancer (DTC) patients. METHODS: In 793 samples derived from 413 patients with DTC, Tg and TgAb were simultaneously measured with two immunometric assays: Immulite 2000XPi and Kryptor compact plus. In addition, a qualitative measurement for TgAb interference (recovery test) was performed on the Kryptor compact plus platform. The extent to which different assays lead to different classifications of response to therapy was evaluated when applying the current cut-offs for Tg. RESULTS: Mean Tg concentrations were 37.4% lower with Kryptor as compared with Immulite. Applying guideline based cut-off values for Tg, 33 (4.7%) samples had a Tg-on concentration ≥1.0 µg/L with Immulite and <1.0 µg/L with Kryptor. Of the samples tested as TgAb+ with at least one assay (n=125), 68 (54.4%) samples showed discrepancy in TgAb status. Differences between Immulite and Kryptor measurements resulted in a change in the response to therapy classification in 94 (12.0%) measurements derived from 67 (16.2%) individual patients. CONCLUSIONS: A substantial portion of DTC patients were classified differently dependent on which Tg and TgAb assays are used, when applying the cut-off values as defined in clinical guidelines. Such differences can significantly affect clinical management. In the context of large between-method variation, the recommended Tg cut-offs in guidelines should be used with wisdom rather than as fixed cut-offs.
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Adenocarcinoma , Neoplasias da Glândula Tireoide , Autoanticorpos , Bioensaio , Humanos , TireoglobulinaRESUMO
OBJECTIVES: Although cold exposure is commonly believed to be causally related to acute viral respiratory infections, its effect on the immune system is largely unexplored. In this study, we determined transcript levels of a large panel of immune genes in blood before and after cold exposure. We included both Dutch Europid and Dutch South Asian men to address whether the immune system is differently regulated in the metabolically vulnerable South Asian population. METHODS: Fasted blood samples were obtained from nonobese Dutch Europid (n = 11; mean age 26 ± 3 y) and Dutch South Asian (n = 12; mean age 28 ± 3 y) men before and directly after short-term (â¼2.5 h) mild cold exposure. Transcript levels of 144 immune genes were measured using a dual-color reverse transcriptase multiplex ligation-dependent probe amplification (dcRT-MLPA) assay. RESULTS: Cold exposure acutely upregulated mRNA levels of GNLY (+35%, P < 0.001) and PRF1 (+45%, P < 0.001), which encode cytotoxic proteins, and CCL4 (+8%, P < 0.01) and CCL5 (+5%, P < 0.05), both pro-inflammatory chemokines. At thermoneutrality, mRNA levels of four markers of the nucleotide-binding oligomerization domain (NOD)-like receptor (NLR)-family, involved in inflammasomes, were lower in Dutch South Asians compared to Dutch Europids, namely NLRP2 (-57%, P < 0.05), NLRP7 (-17%, P < 0.05), NLRP10 (-21%, P < 0.05), and NLRC4 (-23%, P < 0.05). CONCLUSIONS: Mild cold exposure acutely increases mRNA levels of genes involved in cytotoxicity of immune cells in blood. In addition, Dutch South Asians display lower circulating mRNA levels of inflammasome genes compared to Dutch Europids.
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Povo Asiático , Jejum , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Povo Asiático/genética , Humanos , Masculino , RNA Mensageiro/genética , Adulto JovemRESUMO
The in vitro diagnostic medical devices regulation (IVDR) will take effect in May 2022. This regulation has a large impact on both the manufacturers of in vitro diagnostic medical devices (IVD) and clinical laboratories. For clinical laboratories, the IVDR poses restrictions on the use of laboratory developed tests (LDTs). To provide a uniform interpretation of the IVDR for colleagues in clinical practice, the IVDR Task Force was created by the scientific societies of laboratory specialties in the Netherlands. A guidance document with explanations and interpretations of relevant passages of the IVDR was drafted to help laboratories prepare for the impact of this new legislation. Feedback from interested parties and stakeholders was collected and used to further improve the document. Here we would like to present our approach to our European colleagues and inform them about the impact of the IVDR and, importantly we would like to present potentially useful approaches to fulfill the requirements of the IVDR for LDTs.
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Objectives Our recent survey of 44 mass spectrometry laboratories across 17 countries identified variation in internal standard (IS) choice for the measurement of serum/plasma 17α-hydroxyprogesterone (17OHP) by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The choice of IS may contribute to inter-method variations. This study evaluated the effect of two common isotopically labeled IS on the quantification of 17OHP by LC-MS/MS. Methods Three collaborating LC-MS/MS laboratories from Asia, Europe and Australia, who routinely measure serum 17OHP, compared two IS, (1) IsoSciences carbon-13 labeled 17OHP-[2,3,4-13C3], and (2) IsoSciences deuterated 17OHP-[2,2,4,6,6,21,21,21-2H]. This was performed as part of their routine patient runs using their respective laboratory standard operating procedure. Results The three laboratories measured 99, 89, 95 independent samples, respectively (up to 100 nmol/L) using the 13C- and 2H-labeled IS. The slopes of the Passing-Bablok regression ranged 0.98-1.00 (all 95% confidence interval [CI] estimates included the line of identity), and intercept of <0.1 nmol/L. Average percentage differences of -0.04% to -5.4% were observed between the two IS materials, which were less than the optimal bias specification of 7% determined by biological variation, indicating no clinically significant difference. The results of 12 Royal College of Pathologists of Australasia Quality Assurance Programs (RCPAQAP) proficiency samples (1-40 nmol/L) measured by the laboratories were all within the RCPAQAP analytical performance specifications for both IS. Conclusions Overall, the comparison between the results of 13C- and 2H-labeled IS for 17OHP showed good agreement, and show no clinically significant bias when incorporated into the LC-MS/MS methods employed in the collaborating laboratories.
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17-alfa-Hidroxiprogesterona/sangue , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , 17-alfa-Hidroxiprogesterona/normas , Humanos , Isótopos , Padrões de ReferênciaRESUMO
BACKGROUND/AIMS: The current diagnostic workup of Cushing's syndrome (CS) requires various tests which only capture short-term cortisol exposure, whereas patients with endogenous CS generally have elevated cortisol levels over longer periods of time. Scalp hair assessment has emerged as a convenient test in capturing glucocorticoid concentrations over long periods of time. The aim of this multicenter, multinational, prospective, case-control study was to evaluate the diagnostic efficacy of scalp hair glucocorticoids in screening of endogenous CS. METHODS: We assessed the diagnostic performances of hair cortisol (HairF), hair cortisone (HairE), and the sum of both (sumHairF+E), as measured by a state-of-the-art LC-MS/MS technique, in untreated patients with confirmed endogenous CS (n = 89) as well as in community controls (n = 295) from the population-based Lifelines cohort study. RESULTS: Both glucocorticoids were significantly elevated in CS patients when compared to controls. A high diagnostic efficacy was found for HairF (area under the curve 0.87 [95% CI: 0.83-0.92]), HairE (0.93 [0.89-0.96]), and sumHairF+E (0.92 [0.88-0.96]) (all p < 0.001). The participants were accurately classified at the optimal cutoff threshold in 86% of the cases (81% sensitivity, 88% specificity, and 94% negative predictive value [NPV]) by HairF, in 90% of the cases (87% sensitivity, 90% specificity, and 96% NPV) by HairE, and in 87% of the cases (86% sensitivity, 88% specificity, and 95% NPV) by the sumHairF+E. HairE was shown to be the most accurate in differentiating CS patients from controls. CONCLUSION: Scalp hair glucocorticoids, especially hair cortisone, can be seen as a promising biomarker in screening for CS. Its convenience in collection and workup additionally makes it feasible for first-line screening.
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Biomarcadores/análise , Síndrome de Cushing/diagnóstico , Glucocorticoides/análise , Cabelo/química , Adulto , Idoso , Biomarcadores/metabolismo , Estudos de Casos e Controles , Cromatografia Líquida , Estudos de Coortes , Síndrome de Cushing/metabolismo , Feminino , Alemanha , Glucocorticoides/metabolismo , Cabelo/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Espectrometria de Massas em TandemRESUMO
BACKGROUND: Current perioperative patient care aims to maintain homeostasis by attenuation of the stress response to surgery, as a more vigorous stress response can have detrimental effects on postoperative recovery. This systematic review and meta-analysis aims to assess the effect of perioperative music on the physiological stress response to surgery. METHODS: The Embase, Medline Ovid, Cochrane Central, Web of Science, and Google Scholar databases were searched from inception date until February 5, 2019, using a systematic literature search following the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines for randomized controlled trials investigating the effect of music before, during, and/or after surgery in adult surgical patients on the stress response to surgery. Meta-analysis was performed using a random effects model and pooled standardized mean differences were calculated with 95% confidence intervals. This study was registered in the PROSPERO database (CRD42018097060). RESULTS: The literature search identified 1076 articles. Eighteen studies (1301 patients) were included in the systematic review, of which eight were included in the meta-analysis. Perioperative music attenuated the neuroendocrine cortisol stress response to surgery (pooled standardized mean difference -0.30, [95% confidence interval -0.53 to -0.07], P = 0.01, I2 = 0). CONCLUSIONS: Perioperative music can attenuate the neuroendocrine stress response to surgery.
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Música , Assistência Perioperatória , Estresse Psicológico/prevenção & controle , Procedimentos Cirúrgicos Operatórios/psicologia , Hormônio Adrenocorticotrópico/sangue , Viés , Humanos , Hidrocortisona/sangueAssuntos
Hidrocortisona , Hiperaldosteronismo , Espectrometria de Massas , Humanos , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/sangue , Hidrocortisona/sangue , Imunoensaio/métodos , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Glândulas Suprarrenais/irrigação sanguínea , Espectrometria de Massa com Cromatografia LíquidaRESUMO
BACKGROUND: Measurement of adequate glucose concentrations is complicated by in vitro breakdown of glucose due to glycolysis. Unlike the commonly used NaF-EDTA and NaF-oxalate phlebotomy tubes, citrated NaF-EDTA tubes are reported to directly and thereby completely inhibit glycolysis. Recently, Greiner introduced the Vacuette® FC-Mix NaF-EDTA-citrate tube, currently the only NaF-citrate tube without volume-disturbing liquid additions available on the European market. Here we present its potential as alternative for the laborious and therefore unfeasible conditions for glucose sampling as recommended by the World Health Organization (WHO). METHODS: The FC-Mix tube was tested against the WHO recommended method of optimal laboratory conditions, both in healthy volunteers and pregnant woman undergoing oral glucose tolerance test (oGTT) for screening of gestational diabetes mellitus (GDM). Glucose concentrations were measured after different incubation times (0-48 h) and temperatures (room temperature, 37 °C), both in uncentrifuged whole blood and centrifuged material. RESULTS: Deming regression analysis shows that glucose concentrations measured in the FC-Mix tube correlate to the WHO recommended method. Stability is maintained at room temperature for 48 h and at least 24 h at 37 °C. The use of the FC-Mix tube was also validated in screening for GDM and proved comparable to the WHO recommended method in diagnostic outcome. CONCLUSIONS: The new Greiner FC-Mix tube combines the easy handling of a routine tube with dry additive with the ability to immediately inhibit glycolysis as in the WHO method for optimal pre-analytical and analytical conditions and performs equally to those conditions when screening for GDM.
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Flebotomia/instrumentação , Adulto , Glicemia/análise , Citratos/química , Diabetes Gestacional/diagnóstico , Ácido Edético/química , Feminino , Teste de Tolerância a Glucose , Glicólise , Hemólise , Humanos , Flebotomia/métodos , Flebotomia/normas , Gravidez , Fluoreto de Sódio/química , TemperaturaRESUMO
The immune system plays an instrumental role in obesity and insulin resistance. Here, we unravel the role of the costimulatory molecule CD40 and its signaling intermediates, TNF receptor-associated factors (TRAFs), in diet-induced obesity (DIO). Although not exhibiting increased weight gain, male CD40(-/-) mice in DIO displayed worsened insulin resistance, compared with wild-type mice. This worsening was associated with excessive inflammation of adipose tissue (AT), characterized by increased accumulation of CD8(+) T cells and M1 macrophages, and enhanced hepatosteatosis. Mice with deficient CD40-TRAF2/3/5 signaling in MHCII(+) cells exhibited a similar phenotype in DIO as CD40(-/-) mice. In contrast, mice with deficient CD40-TRAF6 signaling in MHCII(+) cells displayed no insulin resistance and showed a reduction in both AT inflammation and hepatosteatosis in DIO. To prove the therapeutic potential of inhibition of CD40-TRAF6 in obesity, DIO mice were treated with a small-molecule inhibitor that we designed to specifically block CD40-TRAF6 interactions; this compound improved insulin sensitivity, reduced AT inflammation, and decreased hepatosteatosis. Our study reveals that the CD40-TRAF2/3/5 signaling pathway in MHCII(+) cells protects against AT inflammation and metabolic complications associated with obesity whereas CD40-TRAF6 interactions in MHCII(+) cells aggravate these complications. Inhibition of CD40-TRAF6 signaling by our compound may provide a therapeutic option in obesity-associated insulin resistance.
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Antígenos CD40/metabolismo , Resistência à Insulina/imunologia , Obesidade/imunologia , Transdução de Sinais/imunologia , Fator 6 Associado a Receptor de TNF/metabolismo , Tecido Adiposo/citologia , Tecido Adiposo/imunologia , Tecido Adiposo/patologia , Análise de Variância , Animais , Compostos Azo , Antígenos CD40/antagonistas & inibidores , Antígenos CD40/genética , Linfócitos T CD8-Positivos/imunologia , Calorimetria , Fígado Gorduroso/etiologia , Fígado Gorduroso/patologia , Citometria de Fluxo , Ligantes , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/complicações , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos , Ressonância de Plasmônio de Superfície , Fator 6 Associado a Receptor de TNF/antagonistas & inibidoresRESUMO
Prolonged niacin treatment elicits beneficial effects on the plasma lipid and lipoprotein profile that is associated with a protective CVD risk profile. Acute niacin treatment inhibits nonesterified fatty acid release from adipocytes and stimulates prostaglandin release from skin Langerhans cells, but the acute effects diminish upon prolonged treatment, while the beneficial effects remain. To gain insight in the prolonged effects of niacin on lipid metabolism in adipocytes, we used a mouse model with a human-like lipoprotein metabolism and drug response [female APOE*3-Leiden.CETP (apoE3 Leiden cholesteryl ester transfer protein) mice] treated with and without niacin for 15 weeks. The gene expression profile of gonadal white adipose tissue (gWAT) from niacin-treated mice showed an upregulation of the "biosynthesis of unsaturated fatty acids" pathway, which was corroborated by quantitative PCR and analysis of the FA ratios in gWAT. Also, adipocytes from niacin-treated mice secreted more of the PUFA DHA ex vivo. This resulted in an increased DHA/arachidonic acid (AA) ratio in the adipocyte FA secretion profile and in plasma of niacin-treated mice. Interestingly, the DHA metabolite 19,20-dihydroxy docosapentaenoic acid (19,20-diHDPA) was increased in plasma of niacin-treated mice. Both an increased DHA/AA ratio and increased 19,20-diHDPA are indicative for an anti-inflammatory profile and may indirectly contribute to the atheroprotective lipid and lipoprotein profile associated with prolonged niacin treatment.
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Anti-Inflamatórios não Esteroides/uso terapêutico , Ácidos Graxos Ômega-3/sangue , Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Gordura Intra-Abdominal/efeitos dos fármacos , Niacina/uso terapêutico , Oxilipinas/sangue , Algoritmos , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Apolipoproteína E3/genética , Apolipoproteína E3/metabolismo , Ácido Araquidônico/sangue , Ácido Araquidônico/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , Proteínas de Transferência de Ésteres de Colesterol/genética , Proteínas de Transferência de Ésteres de Colesterol/metabolismo , Dieta Ocidental/efeitos adversos , Ácidos Docosa-Hexaenoicos/sangue , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Insaturados/sangue , Ácidos Graxos Insaturados/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Hidroxilação , Hiperlipidemias/sangue , Hiperlipidemias/imunologia , Hiperlipidemias/metabolismo , Hipolipemiantes/farmacologia , Gordura Intra-Abdominal/imunologia , Gordura Intra-Abdominal/metabolismo , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/metabolismo , Camundongos Transgênicos , Niacina/farmacologia , Oxilipinas/metabolismo , Fatores de TempoRESUMO
The lipid-lowering effect of niacin has been attributed to the inhibition of cAMP production in adipocytes, thereby inhibiting intracellular lipolysis and release of nonesterified fatty acids (NEFA) to the circulation. However, long-term niacin treatment leads to a normalization of plasma NEFA levels and induces insulin resistance, for which the underlying mechanisms are poorly understood. The current study addressed the effects of long-term niacin treatment on insulin-mediated inhibition of adipocyte lipolysis and focused on the regulation of cAMP levels. APOE*3-Leiden.CETP transgenic mice treated with niacin for 15 wk were subjected to an insulin tolerance test and showed whole body insulin resistance. Similarly, adipocytes isolated from niacin-treated mice were insulin resistant and, interestingly, exhibited an increased response to cAMP stimulation by 8Br-cAMP, ß1- and ß2-adrenergic stimulation. Gene expression analysis of the insulin and ß-adrenergic pathways in adipose tissue indicated that all genes were downregulated, including the gene encoding the cAMP-degrading enzyme phosphodiesterase 3B (PDE3B). In line with this, we showed that insulin induced a lower PDE3B response in adipocytes isolated from niacin-treated mice. Inhibiting PDE3B with cilostazol increased lipolytic responsiveness to cAMP stimulation in adipocytes. These data show that long-term niacin treatment leads to a downregulation of PDE3B in adipocytes, which could explain part of the observed insulin resistance and the increased responsiveness to cAMP stimulation.