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1.
Cell Biosci ; 14(1): 91, 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-38997783

RESUMEN

BACKGROUND: Nor1/NR4A3 is a member of the NR4A subfamily of nuclear receptors that play essential roles in regulating gene expression related to development, cell homeostasis and neurological functions. However, Nor1 is still considered an orphan receptor, as its natural ligand remains unclear for mediating transcriptional activation. Yet other activation signals may modulate Nor1 activity, although their precise role in the development and maintenance of the nervous system remains elusive. METHODS: We used transcriptional reporter assays, gene expression profiling, protein turnover measurement, and cell growth assays to assess the functional relevance of Nor1 and SUMO-defective variants in neuronal cells. SUMO1 and SUMO2 conjugation to Nor1 were assessed by immunoprecipitation. Tubulin stability was determined by acetylation and polymerization assays, and live-cell fluorescent microscopy. RESULTS: Here, we demonstrate that Nor1 undergoes SUMO1 conjugation at Lys-89 within a canonical ψKxE SUMOylation motif, contributing to the complex pattern of Nor1 SUMOylation, which also includes Lys-137. Disruption of Lys-89, thereby preventing SUMO1 conjugation, led to reduced Nor1 transcriptional competence and protein stability, as well as the downregulation of genes involved in cell growth and metabolism, such as ENO3, EN1, and CFLAR, and in microtubule cytoskeleton dynamics, including MAP2 and MAPT, which resulted in reduced survival of neuronal cells. Interestingly, Lys-89 SUMOylation was potentiated in response to nocodazole, a microtubule depolymerizing drug, although this was insufficient to rescue cells from microtubule disruption despite enhanced Nor1 gene expression. Instead, Lys-89 deSUMOylation reduced the expression of microtubule-severing genes like KATNA1, SPAST, and FIGN, and enhanced α-tubulin cellular levels, acetylation, and microfilament organization, promoting microtubule stability and resistance to nocodazole. These effects contrasted with Lys-137 SUMOylation, suggesting distinct regulatory mechanisms based on specific Nor1 input SUMOylation signals. CONCLUSIONS: Our study provides novel insights into Nor1 transcriptional signaling competence and identifies a hierarchical mechanism whereby selective Nor1 SUMOylation may govern neuronal cytoskeleton network dynamics and resistance against microtubule disturbances, a condition strongly associated with neurodegenerative diseases.

2.
Am J Clin Nutr ; 119(5): 1270-1279, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38518848

RESUMEN

BACKGROUND: The substitution of monounsaturated acids (MUFAs) for saturated fatty acids (SFAs) is recommended for cardiovascular disease prevention but its impact on lipoprotein metabolism in subjects with dyslipidemia associated with insulin resistance (IR) remains largely unknown. OBJECTIVES: This study aimed to evaluate the impact of substituting MUFAs for SFAs on the in vivo kinetics of apolipoprotein (apo)B-containing lipoproteins and on the plasma lipidomic profile in adults with IR-induced dyslipidemia. METHODS: Males and females with dyslipidemia associated with IR (n = 18) were recruited for this crossover double-blind randomized controlled trial. Subjects consumed, in random order, a diet rich in SFAs (SFAs: 13.4%E; MUFAs: 14.4%E) and a diet rich in MUFAs (SFAs: 7.1%E; MUFAs: 20.7%E) in fully controlled feeding conditions for periods of 4 wk each, separated by a 4-wk washout. At the end of each diet, fasting plasma samples were taken together with measurements of the in vivo kinetics of apoB-containing lipoproteins. RESULTS: Substituting MUFAs for SFAs had no impact on triglyceride-rich lipoprotein apoB-48 fractional catabolic rate (FCR) (Δ = -8.9%, P = 0.4) and production rate (Δ = 0.0%, P = 0.9), although it decreased very low-density lipoprotein apoB-100 pool size (PS) (Δ = -22.5%; P = 0.01). This substitution also reduced low-density lipoprotein cholesterol (LDL-C) (Δ = -7.0%; P = 0.01), non-high-density lipoprotein cholesterol (Δ = -2.5%; P = 0.04), and LDL apoB-100 PS (Δ = -6.0%; P = 0.05). These differences were partially attributed to an increase in LDL apoB-100 FCR (Δ = +1.6%; P = 0.05). The MUFA diet showed reduced sphingolipid concentrations and elevated glycerophospholipid levels compared with the SFA diet. CONCLUSIONS: This study demonstrated that substituting dietary MUFAs for SFAs decreases LDL-C levels and LDL PS by increasing LDL apoB-100 FCR and results in an overall improved plasma lipidomic profile in individuals with IR-induced lipidemia. TRIAL REGISTRATION: This trial was registered as clinicaltrials.gov as NCT03872349.


Asunto(s)
Apolipoproteína B-100 , Estudios Cruzados , Dislipidemias , Ácidos Grasos Monoinsaturados , Ácidos Grasos , Resistencia a la Insulina , Aceite de Oliva , Humanos , Masculino , Femenino , Dislipidemias/dietoterapia , Apolipoproteína B-100/sangre , Persona de Mediana Edad , Ácidos Grasos/sangre , Adulto , Método Doble Ciego , Grasas de la Dieta
3.
Genes (Basel) ; 14(5)2023 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-37239471

RESUMEN

Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional spinal deformity. The incidence of AIS in females is 8.4 times higher than in males. Several hypotheses on the role of estrogen have been postulated for the progression of AIS. Recently, Centriolar protein gene POC5 (POC5) was identified as a causative gene of AIS. POC5 is a centriolar protein that is important for cell cycle progression and centriole elongation. However, the hormonal regulation of POC5 remains to be determined. Here, we identify POC5 as an estrogen-responsive gene under the regulation of estrogen receptor ERα in normal osteoblasts (NOBs) and other ERα-positive cells. Using promoter activity, gene, and protein expression assays, we found that the POC5 gene was upregulated by the treatment of osteoblasts with estradiol (E2) through direct genomic signaling. We observed different effects of E2 in NOBs and mutant POC5A429V AIS osteoblasts. Using promoter assays, we identified an estrogen response element (ERE) in the proximal promoter of POC5, which conferred estrogen responsiveness through ERα. The recruitment of ERα to the ERE of the POC5 promoter was also potentiated by estrogen. Collectively, these findings suggest that estrogen is an etiological factor in scoliosis through the deregulation of POC5.


Asunto(s)
Proteínas Portadoras , Receptor alfa de Estrógeno , Escoliosis , Humanos , Proteínas Portadoras/genética , Estradiol/farmacología , Receptor alfa de Estrógeno/genética , Receptor alfa de Estrógeno/metabolismo , Estrógenos/farmacología , Escoliosis/genética , Escoliosis/metabolismo
4.
J Lipid Res ; 63(10): 100269, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36030928

RESUMEN

Low circulating concentrations of insulin-like growth factor binding protein-2 (IGFBP-2) have been associated with dyslipidemia, notably with high triglyceride (TG) levels. However, the determinants by which IGFBP-2 influences lipoprotein metabolism, especially that of TG-rich lipoproteins (TRLs), are poorly understood. Here, we aimed to assess the relationships between IGFBP-2 levels and lipoprotein production and catabolism in human subjects. Fasting IGFBP-2 concentrations were measured in the plasma of 219 men pooled from previous lipoprotein kinetics studies. We analyzed production rate and fractional catabolic rates of TRLapoB-48, and LDL-, IDL-, and VLDLapoB-100 by multicompartmental modeling of l-[5,5,5-D3] leucine enrichment data after a 12 h primed constant infusion in individuals kept in a constant nutritional steady state. Subjects had an average BMI of 30 kg/m2, plasma IGFBP-2 levels of 157 ng/ml, and TG of 2.2 mmol/l. After adjustments for age and BMI, IGFBP-2 levels were negatively associated with plasma TG (r = -0.29; P < 0.0001) and positively associated with HDL-cholesterol (r = 0.26; P < 0.0001). In addition, IGFBP-2 levels were positively associated with the fractional catabolic rate of VLDLapoB-100 (r = 0.20; P < 0.01) and IDLapoB-100 (r = 0.19; P < 0.05) and inversely with the production rate of TRLapoB-48 (r = -0.28; P < 0.001). These correlations remained statistically significant after adjustments for age, BMI, and the amount of fat given during the tracer infusion. These findings show that the association between low plasma IGFBP-2 and high TG concentrations could be due to both an impaired clearance of apoB-100-containing VLDL and IDL particles and an increased production of apoB-48-containing chylomicrons. Additional studies are necessary to investigate whether and how IGFBP-2 directly impacts the kinetics of TRL.


Asunto(s)
Apolipoproteínas B , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina , Humanos , Masculino , Apolipoproteína B-100/metabolismo , Apolipoproteína B-48/metabolismo , Apolipoproteínas B/metabolismo , HDL-Colesterol/metabolismo , Quilomicrones/metabolismo , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Cinética , Leucina , Lipoproteínas/metabolismo , Lipoproteínas VLDL/metabolismo , Triglicéridos
5.
Proc Natl Acad Sci U S A ; 119(13): e2115819119, 2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35320041

RESUMEN

SignificanceMost metals display an electron-scattering rate [Formula: see text] that follows [Formula: see text] at low temperatures, as prescribed by Fermi liquid theory. But there are important exceptions. One of the most prominent examples is the "strange" metal regime in overdoped cuprate supercondcutors, which exhibits a linear T dependence of the scattering rate [Formula: see text] that reaches a putative Planckian limit. Here, using cutting-edge computational approaches, we show that T-linear scattering rate can emerge from the overdoped Hubbard model at low temperatures. Our results agree with cuprate experiments in various aspects but challenge the Planckian limit. Finally, by identifying antiferromagnetic fluctuations as the physical origin of the T-linear scattering rate, we discover the microscopic mechanism of strange metallicity in cuprates.

6.
Appl Physiol Nutr Metab ; 47(2): 173-182, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35057638

RESUMEN

The objective of this study was to validate an automated self-administered 24-hour dietary recall web application (R24W) against recovery biomarkers for sodium, potassium and protein intakes and to identify individual characteristics associated with misreporting in a sample of 61 men and 69 women aged 20-65 years from Québec City, Canada. Each participant completed 3 dietary recalls using the R24W, provided two 24-hour urinary samples and completed questionnaires to document psychosocial factors. Mean reported intakes were 2.2%, 2.1% and 5.0% lower than the urinary reference values, respectively, for sodium, potassium and proteins (significant difference for proteins only (p = 0.04)). Deattenuated correlations between the self-reported intake and biomarkers were significant for sodium (r = 0.48), potassium (r = 0.56) and proteins (r = 0.68). Cross-classification showed that 39.7% (sodium), 42.9% (potassium) and 42.1% (proteins) of participants were ranked into the same quartile with both methods and only 4.8% (sodium), 3.2% (potassium) and 0.8% (proteins) were ranked in opposite quartiles. Lower body esteem related to appearance was associated with sodium underreporting in women (r = 0.33, p = 0.006). No other individual factor was found to be associated with misreporting. These results suggest that the R24W has a good validity for the assessment of sodium, potassium and protein intakes in a sample of French-speaking adults. Novelty: The validity of an automated self-administered 24-hour dietary recall web application named the R24W was tested using urinary biomarkers. According to 7 criteria, the R24W was found to have a good validity to assess self-reported intakes of sodium, potassium and proteins.


Asunto(s)
Encuestas sobre Dietas/normas , Proteínas en la Dieta/orina , Aplicaciones Móviles/normas , Potasio en la Dieta/orina , Sodio en la Dieta/orina , Adulto , Anciano , Biomarcadores/orina , Encuestas sobre Dietas/métodos , Femenino , Humanos , Masculino , Recuerdo Mental , Persona de Mediana Edad , Quebec , Reproducibilidad de los Resultados , Encuestas y Cuestionarios/normas , Adulto Joven
7.
Proc Natl Acad Sci U S A ; 118(40)2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34593641

RESUMEN

Experiments have shown that the families of cuprate superconductors that have the largest transition temperature at optimal doping also have the largest oxygen hole content at that doping [D. Rybicki et al., Nat. Commun. 7, 1-6 (2016)]. They have also shown that a large charge-transfer gap [W. Ruan et al., Sci. Bull. (Beijing) 61, 1826-1832 (2016)], a quantity accessible in the normal state, is detrimental to superconductivity. We solve the three-band Hubbard model with cellular dynamical mean-field theory and show that both of these observations follow from the model. Cuprates play a special role among doped charge-transfer insulators of transition metal oxides because copper has the largest covalent bonding with oxygen. Experiments [L. Wang et al., arXiv [Preprint] (2020). https://arxiv.org/abs/2011.05029 (Accessed 10 November 2020)] also suggest that superexchange is at the origin of superconductivity in cuprates. Our results reveal the consistency of these experiments with the above two experimental findings. Indeed, we show that covalency and a charge-transfer gap lead to an effective short-range superexchange interaction between copper spins that ultimately explains pairing and superconductivity in the three-band Hubbard model of cuprates.

8.
FASEB J ; 35(9): e21827, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34383980

RESUMEN

Neuron-derived orphan receptor 1, NR4A3 (Nor1)/NR4A3 is an orphan nuclear receptor involved in the transcriptional control of developmental and neurological functions. Oxidative stress-induced conditions are primarily associated with neurological defects in humans, yet the impact on Nor1-mediated transcription of neuronal genes remains with unknown mechanism. Here, we demonstrate that Nor1 is a non-conventional target of SUMO2/3 conjugation at Lys-137 contained in an atypic ψKxSP motif referred to as the pSuM. Nor1 pSuM SUMOylation differs from the canonical process with the obligate phosphorylation of Ser-139 by Ras signaling to create the required negatively charged interface for SUMOylation. Additional phosphorylation at sites flanking the pSuM is also mediated by the coordinated action of protein kinase casein kinase 2 to function as a small ubiquitin-like modifier enhancer, regulating Nor1-mediated transcription and proteasomal degradation. Nor1 responsive genes involved in cell proliferation and metabolism, such as activating transcription factor 3, cyclin D1, CASP8 and FADD-like apoptosis regulator, and enolase 3 were upregulated in response to pSuM disruption in mouse HT-22 hippocampal neuronal cells and human neuroblastoma SH-SY5Y cells. We also identified critical antioxidant genes, such as catalase, superoxide dismutase 1, and microsomal glutathione S-transferase 2, as responsive targets of Nor1 under pSuM regulation. Nor1 SUMOylation impaired gene transcription through less effective Nor1 chromatin binding and reduced enrichment of histone H3K27ac marks to gene promoters. These effects resulted in decreased neuronal cell growth, increased apoptosis, and reduced survival to oxidative stress damage, underlying the role of pSuM-modified Nor1 in redox homeostasis. Our findings uncover a hierarchical post-translational mechanism that dictates Nor1 non-canonical SUMOylation, disrupting Nor1 transcriptional competence, and neuroprotective redox sensitivity.


Asunto(s)
Supervivencia Celular/genética , Proteínas de Unión al ADN/genética , Receptores de Esteroides/genética , Receptores de Hormona Tiroidea/genética , Sumoilación/genética , Animales , Apoptosis/genética , Línea Celular , Línea Celular Tumoral , Proliferación Celular/genética , Quinasa de Punto de Control 2/genética , Regulación de la Expresión Génica/genética , Células HEK293 , Hipocampo/metabolismo , Homeostasis/genética , Humanos , Ratones , Neuroblastoma/genética , Neuronas/metabolismo , Oxidación-Reducción , Estrés Oxidativo/genética , Fosforilación/genética , Regiones Promotoras Genéticas/genética , Procesamiento Proteico-Postraduccional/genética , Transcripción Genética/genética , Activación Transcripcional/genética , Regulación hacia Arriba/genética
9.
J Clin Endocrinol Metab ; 106(11): 3295-3311, 2021 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-34245263

RESUMEN

CONTEXT: Intrauterine growth restriction (IUGR) is an immediate outcome of an adverse womb environment, exposing newborns to developing cardiometabolic disorders later in life. OBJECTIVE: This study investigates the cardiac metabolic consequences and underlying mechanism of energy expenditure in developing fetuses under conditions of IUGR. METHODS: Using an animal model of IUGR characterized by uteroplacental vascular insufficiency, mitochondrial function, gene profiling, lipidomic analysis, and transcriptional assay were determined in fetal cardiac tissue and cardiomyocytes. RESULTS: IUGR fetuses exhibited an upregulation of key genes associated with fatty acid breakdown and ß-oxidation (Acadvl, Acadl, Acaa2), and mitochondrial carnitine shuttle (Cpt1a, Cpt2), instigating a metabolic gene reprogramming in the heart. Induction of Ech1, Acox1, Acox3, Acsl1, and Pex11a indicated a coordinated interplay with peroxisomal ß-oxidation and biogenesis mainly observed in females, suggesting sexual dimorphism in peroxisomal activation. Concurring with the sex-related changes, mitochondrial respiration rates were stronger in IUGR female fetal cardiomyocytes, accounting for enhanced adenosine 5'-triphosphate production. Mitochondrial biogenesis was induced in fetal hearts with elevated expression of Ppargc1a transcript specifically in IUGR females. Lipidomic analysis identified the accumulation of arachidonic, eicosapentaenoic, and docosapentaenoic polyunsaturated long-chain fatty acids (LCFAs) in IUGR fetal hearts, which leads to nuclear receptor peroxisome proliferator-activated receptor α (PPARα) transcriptional activation in cardiomyocytes. Also, the enrichment of H3K27ac chromatin marks to PPARα-responsive metabolic genes in IUGR fetal hearts outlines an epigenetic control in the early metabolic energy switch. CONCLUSION: This study describes a premature and sex-related remodeling of cardiac metabolism in response to an unfavorable intrauterine environment, with specific LCFAs that may serve as predictive effectors leading to IUGR.


Asunto(s)
Metabolismo Energético , Ácidos Grasos/metabolismo , Retardo del Crecimiento Fetal/patología , Corazón Fetal/patología , Mitocondrias/patología , Miocitos Cardíacos/patología , Animales , Animales Recién Nacidos , Femenino , Retardo del Crecimiento Fetal/metabolismo , Corazón Fetal/metabolismo , Masculino , Mitocondrias/metabolismo , Miocitos Cardíacos/metabolismo , Oxidación-Reducción , Ratas Sprague-Dawley , Factores Sexuales
10.
Proc Natl Acad Sci U S A ; 118(25)2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34161286

RESUMEN

A key open issue in condensed-matter physics is how quantum and classical correlations emerge in an unconventional superconductor from the underlying normal state. We study this problem in a doped Mott insulator with information-theory tools on the two-dimensional (2D) Hubbard model at finite temperature with cluster dynamical mean-field theory. We find that the local entropy detects the superconducting state and that the difference in the local entropy between the superconducting and normal states follows the same difference in the potential energy. We find that the thermodynamic entropy is suppressed in the superconducting state and monotonically decreases with decreasing doping. The maximum in entropy found in the normal state above the overdoped region of the superconducting dome is obliterated by superconductivity. The total mutual information, which quantifies quantum and classical correlations, is amplified in the superconducting state of the doped Mott insulator for all doping levels and shows a broad peak versus doping, as a result of competing quantum and classical effects.

11.
CJC Open ; 3(1): 62-70, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33458634

RESUMEN

BACKGROUND: Determinants of coronary artery calcification (CAC) prevalence and severity in heterozygous familial hypercholesterolemia (HeFH) remain understudied. The objective of this cross-sectional study was to investigate correlates of CAC in patients with HeFH. METHODS: A CAC score was calculated by a noncontrast computed tomography scan in women (n = 68) and men (n = 78) with genetically defined HeFH. We classified CAC prevalence and severity using 3 categories: CAC score = 0 Agatston Unit (AU), CAC score = 1-100 AU, and CAC score > 100 AU. Information on potential correlates of CAC including familial and personal health history, cardiovascular risk factors, lipid-lowering medication, and lifestyle habits was collected. RESULTS: A total of 95 patients had prevalent CAC. Independent correlates of CAC prevalence and severity included age (odds ratio [OR] per 10 years: 5.06, 95% confidence interval [CI]: 3.19, 7.93, P < 0.0001), family history of premature cardiovascular disease (OR: 3.88, 95% CI: 1.71, 8.81, P = 0.001), male sex (OR: 3.40, 95% CI: 1.49, 7.78, P = 0.004), statin use (OR: 15.5, 95% CI: 1.89, 126, P = 0.01), diet quality assessed with the Alternative Healthy Eating Index score (OR per 1 standard deviation: 0.59, 95% CI: 0.39, 0.90, P = 0.01), ever smoking (OR: 3.06, 95% CI: 1.20, 7.81, P = 0.02), receptor-negative genotype (OR: 3.17, 95% CI: 1.16, 8.66, P = 0.02), lipoprotein(a) year-score (OR per 1 standard deviation of log-transformed year-score: 1.53, 95% CI: 0.99, 2.36, P = 0.05). CONCLUSIONS: In individuals with HeFH, age, family history of premature cardiovascular disease, sex, statin use, diet quality, smoking status, the LDLR genotype, and lipoprotein(a) concentrations were independently associated with CAC prevalence and severity.


CONTEXTE: Les déterminants de la prévalence et de la sévérité de la calcification des artères coronaires (CAC) dans l'hypercholestérolémie familiale hétérozygote (HFHe) demeurent peu étudiés. L'objectif de cette étude transversale était d'identifier les corrélats de la CAC chez des patients atteints d'HFHe. MÉTHODOLOGIE: Un score calcique coronarien (SCC) a été calculé par un examen de tomodensitométrie sans contraste chez des femmes (n = 68) et des hommes (n = 78) avec HFHe génétiquement définie. Nous avons classé la prévalence et la gravité de la CAC en trois catégories : SCC = 0 unité d'Agatston (UA), SCC = 1 à 100 UA et SCC > 100 UA. Des renseignements ont été recueillis sur des corrélats potentiels de la CAC, dont les antécédents médicaux familiaux et personnels, les facteurs de risque cardiovasculaire, les médicaments hypolipidémiants et les habitudes de vie. RÉSULTATS: Au total, 95 patients présentaient une CAC. Les corrélats indépendants de la prévalence et de la gravité de la CAC comprenaient l'âge (rapport de cotes [RC] par tranche de 10 ans : 5,06; intervalle de confiance [IC] à 95 % : 3,19 à 7,93; p < 0,0001), des antécédents familiaux de maladie cardiovasculaire précoce (RC : 3,88; IC à 95 % : 1,71 à 8,81; p = 0,001), le sexe masculin (RC : 3,40; IC à 95 % : 1,49 à 7,78; p = 0,004), l'emploi de statines (RC : 15,5; IC à 95 % : 1,89 à 126; p = 0,01), la qualité du régime alimentaire évaluée selon le score AHEI (Alternative Healthy Eating Index) (RC par écart-type : 0,59; IC à 95 % : 0,39 à 0,90; p = 0,01), le tabagisme (RC : 3,06; IC à 95 % : 1,20 à 7,81; p = 0,02), le génotype récepteur-négatif (RC : 3,17; IC à 95 % : 1,16 à 8,66; p = 0,02) et le score lipoprotéine(a)-année (RC par écart-type du score-année transformé en logarithme : 1,53; IC à 95 % : 0,99 à 2,36; p = 0,05). CONCLUSIONS: Chez les personnes atteintes d'HFHe, l'âge, les antécédents familiaux de maladie cardiovasculaire précoce, le sexe, l'emploi de statines, la qualité du régime alimentaire, le statut de tabagisme, le génotype du LDLR et les concentrations de lipoprotéine(a) ont été associés de façon indépendante à la prévalence et à la gravité de la CAC.

12.
Diabetol Metab Syndr ; 12: 31, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32292494

RESUMEN

BACKGROUND: Evidence suggests that pathophysiological conditions such as obesity and type 2 diabetes (T2D) are associated with morphologic and metabolic alterations in the small intestinal mucosa. Exploring these alterations generally requires invasive methods, limiting data acquisition to subjects with enteropathies or undergoing bariatric surgery. We aimed to evaluate small intestine epithelial cell homeostasis in a cohort of men covering a wide range of adiposity and glucose homoeostasis statuses. METHODS: Plasma levels of citrulline, a biomarker of enterocyte mass, and I-FABP, a biomarker of enterocyte death, were measured by UHPLC­MS and ELISA in 154 nondiabetic men and 67 men with a T2D diagnosis. RESULTS: Plasma citrulline was significantly reduced in men with insulin resistance and T2D compared to insulin sensitive men. Decreased citrulline levels were, however, not observed in men with uncontrolled metabolic parameters during T2D. Plasma I-FABP was significantly higher in men with T2D, especially in presence of uncontrolled glycemic and lipid profile parameters. Integration of both parameters, which estimate enterocyte turnover, was associated with glucose homeostasis as well as with T2D diagnosis. Differences in biomarkers levels were independent of age and BMI and glucose filtration rates. CONCLUSIONS: Our study supports a decreased functional enterocyte mass and an increased enterocyte death rate in presence of metabolic alterations but emphasizes that epithelial cell homeostasis is especially altered in presence of severe insulin resistance and T2D. The marked changes in small intestine cellularity observed in obesity and diabetes are thus suggested to be part of gut dysfunctions, mainly at an advanced stage of the disease.

13.
Forensic Sci Int ; 308: 110181, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32058268

RESUMEN

One of the primary interests of forensic sciences is the study of traces, better conceived as silent witnesses to criminal activity whose existence is attributable to Locard's principle. Thus, textile fibers are commonly exploited as they are easily transferred during contact which can vary in intensity depending upon the type of activity that occurred. Regardless, current knowledge pertaining to fiber transfer mechanisms, particularly in regards to blended textiles, is limited. It is recognized that the intensity of the contact, the type of textile as well as the size and type of fibers composing it have a significant influence on the amount of fibers transferred. However, when the donor textile is blended (eg. 50% cotton, 50% polyester), it often happens that one of the two types of fibers is transferred in greater proportion to the receiving surface (eg. 80% cotton and 20% polyester). The percentages indicated on the manufactured label are however not representative of the respective proportions (based on the number of fibers) of each type of fiber composing the fabric, but rather the weight of each respective type of fiber used to fabricate the garment. Therefore, the amount of collected fibers (traces) cannot be easily correlated to the proportions indicated on the manufactured label used to describe the textile. The objective of this study was to test the transfer capacities of blended textiles of different cotton and polyester proportions by performing several simulations under controlled conditions (i.e. contact between two textiles with a constant force and speed). The results were then correlated to the fiber type, morphology, and size. Overall, the project contributes to improving the comprehension of fiber transfer mechanisms, and provides insight on the quantity and the proportions of fibers capable of being transferred between the donor and the recipient textiles following a specific type of action and contact (legitimate or otherwise).

14.
Forensic Sci Int ; 303: 109946, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31546161

RESUMEN

A few recent studies attempted to evaluate the differentiation of paints at a production batch level and reported results depending largely on the paint type. The discrimination from production batches is much more random than brands and/or models levels and subject to many unknowns, which suggests that a particular production batch can suddenly present a substantially different composition than the one produced right before or right after it. To add to this existing complexity, most of the paint companies now propose a range of recycled paints among their products. These recycled paints are composed of wastes collected by recycling plants, sorted by their color and binder type (i.e. latex, alkyds), and mixed together in large tanks to form the basis material for future formulations. Quality controls on these recycled batches are voluntarily less precise, and a higher variation is expected in esthetic and chemical properties of the paint. In this project, we collaborated with a North American paint producer that gave us access to its samples, paint formulations recipes, and a summary of the quality controls and corrections they performed on each production batches. The whole study was conducted blindfold and a final verification was made with the manufacturer to evaluate the accuracy of the results. The data set comprised two models of regular paints and two models of recycled paint. Five different production batches were collected per model for a total of 20 samples analyzed by Microscopy, Infrared spectroscopy, Raman spectroscopy, and Pyrolysis GC/MS.

15.
Biol Open ; 8(1)2019 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-30598481

RESUMEN

The physiological role and the regulation of ADGRG7 are not yet elucidated. The functional involvement of this receptor was linked with different physiological process such as reduced body weight, gastrointestinal function and recently, a gene variant in ADGRG7 was observed in patients with adolescent idiopathic scoliosis. Here, we identify the ADGRG7 as an estrogen-responsive gene under the regulation of estrogen receptor ERα in scoliotic osteoblasts and other cells lines. We found that ADGRG7 expression was upregulated in response to estrogen (E2) in adolescent idiopathic scoliosis (AIS) cells. ADGRG7 promoter studies indicate the presence of an ERα response half site in close vicinity of a specificity protein 1 (SP1) binding site. Mutation of the SP1 site completely abrogated the response to E2, indicating its essential requirement. ChIP confirmed the binding of SP1 and ERα to the ADGRG7 promoter. Our results identify the ADGRG7 gene as an estrogen-responsive gene under the control of ERα and SP1 tethered actions, suggesting a possible role of estrogens in the regulation of ADGRG7 This article has an associated First Person interview with the first author of the paper.

16.
J Clin Lipidol ; 12(6): 1383-1389, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30318453

RESUMEN

BACKGROUND: Type III hyperlipoproteinemia is a highly atherogenic dyslipoproteinemia characterized by hypercholesterolemia and hypertriglyceridemia due to markedly increased numbers of cholesterol-enriched chylomicron and very-low-density lipoprotein (VLDL) remnant lipoprotein particles. Type III can be distinguished from mixed hyperlipidemia based on a simple diagnostic algorithm, which involves total cholesterol, triglycerides, and apolipoprotein B (apoB). However, apoB is not measured routinely. OBJECTIVE: The objective of the present study was to determine if patients with type III could be distinguished from mixed hyperlipidemia based on lipoprotein lipids. METHODS: Classification was based first on total cholesterol and triglyceride and then on the apoB diagnostic algorithm using apoB plus total cholesterol plus triglycerides, and validated by sequential ultracentrifugation. Four hundred and forty normals, 637 patients with hypertriglyceridemia, and 714 with hypertriglyceridemia and hypercholesterolemia were studied. Plasma lipoproteins were separated by sequential ultracentrifugation and heparin-manganese precipitation. Cholesterol, triglyceride, and apoB were measured in plasma and isolated lipoprotein fractions. RESULTS: Of the 1351 patients with hypertriglyceridemia, 49 had type III hyperlipoproteinemia, as diagnosed by the apoB algorithm and validated by ultracentrifugation. Plasma triglycerides were higher in the type III subjects: 4.16 mmol/L (3.35-6.08, 25th-75th percentile), but there was considerable overlap with the hypertriglyceridemic subjects 2.65 mmol/L (1.91-4.20, 25th-75th percentile) and the combined hyperlipidemic subjects 3.02 mmol/L (2.07-5.32, 25th-75th percentile). Similarly, total cholesterol was 4.79 mmol/L (4.31-5.58, 25th-75th percentile) for type III vs 5.5 mmol/L (4.64-5.78, 25th-75th percentile) and 7.02 mmol/L (6.39-7.96, 25th-75th percentile), respectively. By contrast, as identified by the apoB algorithm, the VLDL-C/TG, VLDL-C/VLDL-TG, VLDL-C/VLDL apoB, and VLDL apoB/LDL apoB ratios were all higher in type III than in the other hypertriglyceridemic dyslipoproteinemias with the exception of type V as diagnosed by the apoB algorithm. CONCLUSION: Cholesterol and triglycerides cannot reliably distinguish type III hyperlipoproteinemia from mixed hyperlipidemia. Adding apoB and applying the apoB algorithm makes reliable diagnosis possible and easy. However, unless apoB is introduced into routine clinical care, type III hyperlipoproteinemia will often not be recognized. Given the cardiovascular risk associated with type III and its responsiveness to treatment, this should not be acceptable.


Asunto(s)
Hiperlipoproteinemia Tipo III/diagnóstico , Hipertrigliceridemia/diagnóstico , Adolescente , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Hiperlipoproteinemia Tipo III/sangre , Hipertrigliceridemia/sangre , Lipoproteínas/sangre , Masculino , Persona de Mediana Edad , Adulto Joven
17.
Mol Oncol ; 12(10): 1689-1705, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30051594

RESUMEN

Ovarian cancer (OC) is one of the most intractable diseases, exhibiting tremendous molecular heterogeneity and lacking reliable methods for screening, resulting in late diagnosis and widespread peritoneal dissemination. Menopausal estrogen replacement therapy is a well-recognized risk factor for OC, but little is known about how estrogen might contribute to this disease at the cellular level. This study identifies chemokine receptor CXCR7/ACKR3 as an estrogen-responsive gene, whose expression is markedly enhanced by estrogen through direct recruitment of ERα and transcriptional active histone modifications in OC cells. The gene encoding CXCR7 chemokine ligand I-TAC/CXCL11 was also upregulated by estrogen, resulting in Ser-118 phosphorylation, activation, and recruitment of estrogen receptor ERα at the CXCR7 promoter locus for positive feedback regulation. Both CXCR7 and CXCL11, but not CXCR3 (also recognized to interact with CXCL11), were found to be significantly increased in stromal sections of microdissected tumors and positively correlated in mesenchymal subtype of OC. Estrogenic induction of mesenchymal markers SNAI1, SNAI2, and CDH2 expression, with a consequent increase in cancer cell migration, was shown to depend on CXCR7, indicating a key role for CXCR7 in mediating estrogen upregulation of mesenchymal markers to induce invasion of OC cells. These findings identify a feed-forward mechanism that sustains activation of the CXCR7/CXCL11 axis under ERα control to induce the epithelial-mesenchymal transition pathway and metastatic behavior of OC cells. Such interplay underlies the complex gene profile heterogeneity of OC that promotes changes in tumor microenvironment and metastatic acquisition.


Asunto(s)
Quimiocina CXCL11/metabolismo , Receptor alfa de Estrógeno/metabolismo , Retroalimentación Fisiológica , Neoplasias Ováricas/metabolismo , Receptores CXCR/metabolismo , Sitios de Unión , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Cromatina/metabolismo , Transición Epitelial-Mesenquimal/efectos de los fármacos , Estrógenos/farmacología , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Sitios Genéticos , Humanos , Mesodermo/efectos de los fármacos , Mesodermo/metabolismo , Mesodermo/patología , Neoplasias Ováricas/patología , Fosforilación/efectos de los fármacos , Fosfoserina/metabolismo , Receptores CXCR/genética , Elementos de Respuesta/genética , Transducción de Señal/efectos de los fármacos , Células del Estroma/efectos de los fármacos , Células del Estroma/metabolismo , Transcripción Genética/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos
18.
Int J Mol Sci ; 19(5)2018 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-29883404

RESUMEN

Uncovering the biological role of nuclear receptor peroxisome proliferator-activated receptors (PPARs) has greatly advanced our knowledge of the transcriptional control of glucose and energy metabolism. As such, pharmacological activation of PPARγ has emerged as an efficient approach for treating metabolic disorders with the current use of thiazolidinediones to improve insulin resistance in diabetic patients. The recent identification of growth hormone releasing peptides (GHRP) as potent inducers of PPARγ through activation of the scavenger receptor CD36 has defined a novel alternative to regulate essential aspects of lipid and energy metabolism. Recent advances on the emerging role of CD36 and GHRP hexarelin in regulating PPARγ downstream actions with benefits on atherosclerosis, hepatic cholesterol biosynthesis and fat mitochondrial biogenesis are summarized here. The response of PPARγ coactivator PGC-1 is also discussed in these effects. The identification of the GHRP-CD36-PPARγ pathway in controlling various tissue metabolic functions provides an interesting option for metabolic disorders.


Asunto(s)
Antígenos CD36/metabolismo , Enfermedades Metabólicas/metabolismo , PPAR gamma/metabolismo , Transducción de Señal , Animales , Antígenos CD36/agonistas , Descubrimiento de Drogas , Metabolismo Energético/efectos de los fármacos , Ácidos Grasos/metabolismo , Humanos , Resistencia a la Insulina , Enfermedades Metabólicas/tratamiento farmacológico , Enfermedades Metabólicas/patología , Oligopéptidos/farmacología , Oligopéptidos/uso terapéutico , PPAR gamma/agonistas , Transducción de Señal/efectos de los fármacos
19.
J Lipid Res ; 59(8): 1501-1509, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29946054

RESUMEN

Intestinal triglyceride (TG)-rich lipoproteins (TRLs) are important in the pathogenesis of atherosclerosis in insulin resistance (IR). We investigated the association of plasma proprotein convertase subtilisin/kexin type 9 (PCSK9) concentrations with apoB-48-containing TRL metabolism in 148 men displaying various degrees of IR by measuring in vivo kinetics of TRL apoB-48 during a constant-fed state after a primed-constant infusion of L-[5,5,5-D3]leucine. Plasma PCSK9 concentrations positively correlated with TRL apoB-48 pool size (r = 0.31, P = 0.0002) and production rate (r = 0.24, P = 0.008) but not the fractional catabolic rate (r = -0.04, P = 0.6). Backward stepwise multiple linear regression analysis identified PCSK9 concentrations as a positive predictor of TRL apoB-48 production rate (standard ß = +0.20, P = 0.007) independent of BMI, age, T2D/metformin use, dietary fat intake during the kinetic study, and fasting concentrations of TGs, insulin, glucose, LDL cholesterol, or C-reactive protein. We also assessed intestinal expression of key genes involved in chylomicron processing from duodenal samples of 71 men. Expression of PCSK9 and HMG-CoAR genes was positively associated (r = 0.43, P = 0.002). These results support PCSK9 association with intestinal secretion and plasma overaccumulation of TRL apoB-48 in men with IR.


Asunto(s)
Apolipoproteína B-48/química , Resistencia a la Insulina , Lipoproteínas/sangre , Lipoproteínas/química , Proproteína Convertasa 9/sangre , Triglicéridos/química , Adulto , Apolipoproteína B-48/sangre , Células CACO-2 , Estudios Transversales , Regulación de la Expresión Génica , Humanos , Mucosa Intestinal/metabolismo , Masculino , Persona de Mediana Edad , Adulto Joven
20.
J Clin Endocrinol Metab ; 103(8): 2909-2917, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29846653

RESUMEN

Context: Supplementation with high-dose docosahexaenoic acid (DHA) increases serum low-density lipoprotein (LDL) cholesterol (LDL-C) concentrations more than high-dose eicosapentaenoic acid (EPA). The mechanisms underlying this difference are unknown. Objective: To examine the phenotypic change in LDL and mechanisms responsible for the differential LDL-C response to EPA and DHA supplementation in men and women at risk of cardiovascular disease. Design, Setting, Participants, and Intervention: In a double-blind, controlled, crossover study, 48 men and 106 women with abdominal obesity and subclinical inflammation were randomized to a sequence of three treatment phases: phase 1, 2.7 g/d of EPA; phase 2, 2.7 g/d of DHA; and phase 3, 3 g/d of corn oil. All supplements were provided as three 1-g capsules for a total of 3 g/d. The 10-week treatment phases were separated by a 9-week washout period. Main Outcome Measure: In vivo kinetics of apolipoprotein (apo)B100-containing lipoproteins were assessed using primed-constant infusion of deuterated leucine at the end of each treatment in a subset of participants (n = 19). Results: Compared with EPA, DHA increased LDL-C concentrations (+3.3%; P = 0.038) and mean LDL particle size (+0.7 Å; P < 0.001) and reduced the proportion of small LDL (-3.2%; P < 0.01). Both EPA and DHA decreased proprotein convertase subtilisin/kexin type 9 concentrations similarly (-18.2% vs -25.0%; P < 0.0001 vs control). Compared with EPA, DHA supplementation increased both the LDL apoB100 fractional catabolic rate (+11.4%; P = 0.008) and the production rate (+9.4%; P = 0.03). Conclusions: The results of the present study have shown that supplementation with high-dose DHA increases LDL turnover and contributes to larger LDL particles compared with EPA.


Asunto(s)
LDL-Colesterol/sangre , Ácidos Docosahexaenoicos/farmacología , Ácido Eicosapentaenoico/farmacología , Inflamación/sangre , Obesidad Abdominal/sangre , Adolescente , Adulto , Anciano , Estudios Cruzados , Suplementos Dietéticos , Ácidos Docosahexaenoicos/administración & dosificación , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Ácido Eicosapentaenoico/administración & dosificación , Femenino , Humanos , Inflamación/dietoterapia , Masculino , Persona de Mediana Edad , Obesidad Abdominal/dietoterapia , Adulto Joven
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