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1.
Cell ; 187(16): 4176-4192.e17, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-38959890

ABSTRACT

Hypothalamic neural circuits regulate instinctive behaviors such as food seeking, the fight/flight response, socialization, and maternal care. Here, we identified microdeletions on chromosome Xq23 disrupting the brain-expressed transient receptor potential (TRP) channel 5 (TRPC5). This family of channels detects sensory stimuli and converts them into electrical signals interpretable by the brain. Male TRPC5 deletion carriers exhibited food seeking, obesity, anxiety, and autism, which were recapitulated in knockin male mice harboring a human loss-of-function TRPC5 mutation. Women carrying TRPC5 deletions had severe postpartum depression. As mothers, female knockin mice exhibited anhedonia and depression-like behavior with impaired care of offspring. Deletion of Trpc5 from oxytocin neurons in the hypothalamic paraventricular nucleus caused obesity in both sexes and postpartum depressive behavior in females, while Trpc5 overexpression in oxytocin neurons in knock-in mice reversed these phenotypes. We demonstrate that TRPC5 plays a pivotal role in mediating innate human behaviors fundamental to survival, including food seeking and maternal care.


Subject(s)
Depression, Postpartum , Neurons , Obesity , TRPC Cation Channels , Animals , Female , Mice , Obesity/metabolism , Obesity/genetics , Male , Humans , TRPC Cation Channels/metabolism , TRPC Cation Channels/genetics , Depression, Postpartum/metabolism , Neurons/metabolism , Paraventricular Hypothalamic Nucleus/metabolism , Mice, Inbred C57BL , Oxytocin/metabolism , Maternal Behavior
2.
Cell ; 177(3): 597-607.e9, 2019 04 18.
Article in English | MEDLINE | ID: mdl-31002796

ABSTRACT

The melanocortin 4 receptor (MC4R) is a G protein-coupled receptor whose disruption causes obesity. We functionally characterized 61 MC4R variants identified in 0.5 million people from UK Biobank and examined their associations with body mass index (BMI) and obesity-related cardiometabolic diseases. We found that the maximal efficacy of ß-arrestin recruitment to MC4R, rather than canonical Gαs-mediated cyclic adenosine-monophosphate production, explained 88% of the variance in the association of MC4R variants with BMI. While most MC4R variants caused loss of function, a subset caused gain of function; these variants were associated with significantly lower BMI and lower odds of obesity, type 2 diabetes, and coronary artery disease. Protective associations were driven by MC4R variants exhibiting signaling bias toward ß-arrestin recruitment and increased mitogen-activated protein kinase pathway activation. Harnessing ß-arrestin-biased MC4R signaling may represent an effective strategy for weight loss and the treatment of obesity-related cardiometabolic diseases.


Subject(s)
Gain of Function Mutation/genetics , Obesity/pathology , Receptor, Melanocortin, Type 4/genetics , Signal Transduction , Adult , Aged , Body Mass Index , Coronary Artery Disease/complications , Coronary Artery Disease/metabolism , Coronary Artery Disease/pathology , Cyclic AMP/metabolism , Databases, Factual , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/pathology , Female , GTP-Binding Protein alpha Subunits, Gs/metabolism , Genetic Predisposition to Disease , Genotype , Humans , Male , Middle Aged , Obesity/complications , Obesity/metabolism , Polymorphism, Single Nucleotide , Receptor, Melanocortin, Type 4/chemistry , Receptor, Melanocortin, Type 4/metabolism , beta-Arrestins/metabolism
3.
Cell ; 176(4): 729-742.e18, 2019 02 07.
Article in English | MEDLINE | ID: mdl-30661757

ABSTRACT

Hypothalamic melanocortin neurons play a pivotal role in weight regulation. Here, we examined the contribution of Semaphorin 3 (SEMA3) signaling to the development of these circuits. In genetic studies, we found 40 rare variants in SEMA3A-G and their receptors (PLXNA1-4; NRP1-2) in 573 severely obese individuals; variants disrupted secretion and/or signaling through multiple molecular mechanisms. Rare variants in this set of genes were significantly enriched in 982 severely obese cases compared to 4,449 controls. In a zebrafish mutagenesis screen, deletion of 7 genes in this pathway led to increased somatic growth and/or adiposity demonstrating that disruption of Semaphorin 3 signaling perturbs energy homeostasis. In mice, deletion of the Neuropilin-2 receptor in Pro-opiomelanocortin neurons disrupted their projections from the arcuate to the paraventricular nucleus, reduced energy expenditure, and caused weight gain. Cumulatively, these studies demonstrate that SEMA3-mediated signaling drives the development of hypothalamic melanocortin circuits involved in energy homeostasis.


Subject(s)
Energy Metabolism/genetics , Melanocortins/metabolism , Semaphorins/genetics , Adolescent , Adult , Animals , Body Weight , Cell Line , Child , Child, Preschool , Disease Models, Animal , Eating , Female , Genetic Variation/genetics , Homeostasis , Humans , Hypothalamus/metabolism , Leptin/metabolism , Male , Mice , Mice, Inbred C57BL , Middle Aged , Nerve Tissue Proteins/metabolism , Neurons/metabolism , Obesity/genetics , Obesity/metabolism , Receptors, Cell Surface/metabolism , Semaphorins/metabolism , Young Adult , Zebrafish
4.
J Biol Chem ; 300(8): 107562, 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-39002670

ABSTRACT

The hormone leptin, primarily secreted by adipocytes, plays a crucial role in regulating whole-body energy homeostasis. Homozygous loss-of-function mutations in the leptin gene (LEP) cause hyperphagia and severe obesity, primarily through alterations in leptin's affinity for its receptor or changes in serum leptin concentrations. Although serum concentrations are influenced by various factors (e.g., gene expression, protein synthesis, stability in the serum), proper delivery of leptin from its site of synthesis in the endoplasmic reticulum via the secretory pathway to the extracellular serum is a critical step. However, the regulatory mechanisms and specific machinery involved in this trafficking route, particularly in the context of human LEP mutations, remain largely unexplored. We have employed the Retention Using Selective Hooks system to elucidate the secretory pathway of leptin. We have refined this system into a medium-throughput assay for examining the pathophysiology of a range of obesity-associated LEP variants. Our results reveal that leptin follows the default secretory pathway, with no additional regulatory steps identified prior to secretion. Through screening of leptin variants, we identified three mutations that lead to proteasomal degradation of leptin and one variant that significantly decreased leptin secretion, likely through aberrant disulfide bond formation. These observations have identified novel pathogenic effects of leptin variants, which can be informative for therapeutics and diagnostics. Finally, our novel quantitative screening platform can be adapted for other secreted proteins.

5.
N Engl J Med ; 385(17): 1581-1592, 2021 10 21.
Article in English | MEDLINE | ID: mdl-34614324

ABSTRACT

BACKGROUND: GNAS encodes the Gαs (stimulatory G-protein alpha subunit) protein, which mediates G protein-coupled receptor (GPCR) signaling. GNAS mutations cause developmental delay, short stature, and skeletal abnormalities in a syndrome called Albright's hereditary osteodystrophy. Because of imprinting, mutations on the maternal allele also cause obesity and hormone resistance (pseudohypoparathyroidism). METHODS: We performed exome sequencing and targeted resequencing in 2548 children who presented with severe obesity, and we unexpectedly identified 22 GNAS mutation carriers. We investigated whether the effect of GNAS mutations on melanocortin 4 receptor (MC4R) signaling explains the obesity and whether the variable clinical spectrum in patients might be explained by the results of molecular assays. RESULTS: Almost all GNAS mutations impaired MC4R signaling. A total of 6 of 11 patients who were 12 to 18 years of age had reduced growth. In these patients, mutations disrupted growth hormone-releasing hormone receptor signaling, but growth was unaffected in carriers of mutations that did not affect this signaling pathway (mean standard-deviation score for height, -0.90 vs. 0.75, respectively; P = 0.02). Only 1 of 10 patients who reached final height before or during the study had short stature. GNAS mutations that impaired thyrotropin receptor signaling were associated with developmental delay and with higher thyrotropin levels (mean [±SD], 8.4±4.7 mIU per liter) than those in 340 severely obese children who did not have GNAS mutations (3.9±2.6 mIU per liter; P = 0.004). CONCLUSIONS: Because pathogenic mutations may manifest with obesity alone, screening of children with severe obesity for GNAS deficiency may allow early diagnosis, improving clinical outcomes, and melanocortin agonists may aid in weight loss. GNAS mutations that are identified by means of unbiased genetic testing differentially affect GPCR signaling pathways that contribute to clinical heterogeneity. Monogenic diseases are clinically more variable than their classic descriptions suggest. (Funded by Wellcome and others.).


Subject(s)
GTP-Binding Protein alpha Subunits, Gs/genetics , Mutation , Pediatric Obesity/genetics , Receptor, Melanocortin, Type 4/metabolism , Adolescent , Body Height , Child , Chromogranins/genetics , Female , GTP-Binding Protein alpha Subunits, Gs/deficiency , Humans , Male , Mutation, Missense , Receptors, Thyrotropin/metabolism , Signal Transduction , Exome Sequencing
6.
Mol Ther ; 31(7): 2132-2153, 2023 07 05.
Article in English | MEDLINE | ID: mdl-37194236

ABSTRACT

To leverage complementary mechanisms for cancer cell removal, we developed a novel cell engineering and therapeutic strategy co-opting phagocytic clearance and antigen presentation activity into T cells. We engineered a chimeric engulfment receptor (CER)-1236, which combines the extracellular domain of TIM-4, a phagocytic receptor recognizing the "eat me" signal phosphatidylserine, with intracellular signaling domains (TLR2/TIR, CD28, and CD3ζ) to enhance both TIM-4-mediated phagocytosis and T cell cytotoxic function. CER-1236 T cells demonstrate target-dependent phagocytic function and induce transcriptional signatures of key regulators responsible for phagocytic recognition and uptake, along with cytotoxic mediators. Pre-clinical models of mantle cell lymphoma (MCL) and EGFR mutation-positive non-small cell lung cancer (NSCLC) demonstrate collaborative innate-adaptive anti-tumor immune responses both in vitro and in vivo. Treatment with BTK (MCL) and EGFR (NSCLC) inhibitors increased target ligand, conditionally driving CER-1236 function to augment anti-tumor responses. We also show that activated CER-1236 T cells exhibit superior cross-presentation ability compared with conventional T cells, triggering E7-specific TCR T responses in an HLA class I- and TLR-2-dependent manner, thereby overcoming the limited antigen presentation capacity of conventional T cells. Therefore, CER-1236 T cells have the potential to achieve tumor control by eliciting both direct cytotoxic effects and indirect-mediated cross-priming.


Subject(s)
Antineoplastic Agents , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Adult , T-Lymphocytes , Cross-Priming , Phosphatidylserines , Antigens, Neoplasm , ErbB Receptors , Immunotherapy, Adoptive , Receptors, Antigen, T-Cell/genetics
7.
Sensors (Basel) ; 21(10)2021 May 17.
Article in English | MEDLINE | ID: mdl-34067640

ABSTRACT

The success of a software application is related to users' willingness to keep using it. In this sense, evaluating User eXperience (UX) became an important part of the software development process. Researchers have been carrying out studies by employing various methods to evaluate the UX of software products. Some studies reported varied and even contradictory results when applying different UX evaluation methods, making it difficult for practitioners to identify which results to rely upon. However, these works did not evaluate the developers' perspectives and their impacts on the decision process. Moreover, such studies focused on one-shot evaluations, which cannot assess whether the methods provide the same big picture of the experience (i.e., deteriorating, improving, or stable). This paper presents a longitudinal study in which 68 students evaluated the UX of an online judge system by employing AttrakDiff, UEQ, and Sentence Completion methods at three moments along a semester. This study reveals contrasting results between the methods, which affected developers' decisions and interpretations. With this work, we intend to draw the HCI community's attention to the contrast between different UX evaluation methods and the impact of their outcomes in the software development process.

9.
Zoolog Sci ; 37(2): 128-139, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32282144

ABSTRACT

The family Sicariidae comprises the genera Hexophthalma, Sicarius and Loxosceles. This latter is subdivided in eight monophyletic groups based on genitalia morphology and molecular analyses: amazonica, gaucho, laeta, and spadicea (South America); reclusa (North America); rufescens (Mediterranean); spinulosa and vonwredei (Africa). In Brazil, the genus Loxosceles is represented by 50 species. The mitotic and meiotic characteristics of eight Loxosceles species were analyzed in order to discuss the chromosome evolution, as well as the correspondence between cytogenetic data and morphological/molecular data for the delimitation of the South American groups of species belonging to this genus. All species studied in this work showed 2n♂ = 23, including a X1X2Y sex chromosome system (SCS). Despite the similarity of diploid number and SCS, the species studied here differed regarding the chromosome morphology of some autosomal pairs, presence of secondary constrictions, size of X chromosomes and localization of Ag-NOR/rDNA sites. Based on all these chromosomal data, we verified a close relationship between Loxosceles species belonging to the amazonica and gaucho groups. Transmission electron microscopy (TEM) analysis of spread pachytene cells of L. gaucho showed regular synapsis between homologous autosomal chromosomes, but asynaptic behavior of the sex chromosomes. The axial elements of the sex chromosomes undergo conspicuous morphological modifications resulting in shortening of their length.


Subject(s)
Sex Chromosomes/classification , Spiders/classification , Spiders/genetics , Animals , Brazil , Female , Male , Meiosis , Microscopy, Electron, Transmission , Mitosis , Sex Chromosomes/physiology , Sex Chromosomes/ultrastructure , Species Specificity
10.
Parasitol Res ; 119(7): 2237-2244, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32451718

ABSTRACT

Ecological data on marine mammal parasites represent an excellent opportunity to expand our understanding of host-parasite systems. In this study, we used a dataset of intestinal helminth parasites on 167 long-finned pilot whales Globicephala melas (Traill, 1809) from seven localities in the Faroe Islands to evaluate the extent to which the host's age and sex influence the occurrence, richness, and nested pattern of helminth parasites and the importance of individual hosts to the helminth community. We found positive effects of age on both the occurrence and richness of helminths. Older host individuals showed an ordered accumulation of parasites, as evidenced by the nested pattern in their composition. Males had a higher occurrence of parasites than females, but the richness of helminths did not differ between sexes. Our findings suggest that differences in host-parasite interactions in long-finned pilot whales result mainly from age-structured variations in biological and behavioral characteristics.


Subject(s)
Helminthiasis/epidemiology , Helminths/isolation & purification , Host-Parasite Interactions/physiology , Whales, Pilot/parasitology , Age Distribution , Age Factors , Animals , Denmark/epidemiology , Female , Humans , Intestines/parasitology , Male , Sex Factors
11.
Surg Radiol Anat ; 41(6): 613-624, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31119409

ABSTRACT

PURPOSE: The objective of this review is to provide a structured approach to the main white matter commissures, their anatomic and radiological definition and disease implications. METHODS: The Pubmed database and The JAMA Network were used for the literature review and the following terms were searched using Sort by: Best Match and Sort by: Most Recent: telencephalic commissure, forebrain commissure anatomy, fornix anatomy, commissure of fornix, posterior commissure, corpus callosum, commissural agenesis, Probst bundle, corpus callosum disorders review, corpus callosum diseases review, Marchiafava-Bignami, Alzheimer's disease and Forel commissure; 36 papers were selected, one excluded due to the language barrier. RESULTS: The interhemispheric communication in the brain is achieved via the brain commissures, bundles of white matter linking the two cerebral hemispheres. Anterior white commissure (AWC)-related with olfactory and non-visual communication, hippocampal commissure-main efferent pathway of the hippocampus, connecting the hippocampal formation to structures beyond the temporal lobe, crucial in declarative memory formation and consolidation-and the corpus callosum (CC)-from the anterior commissure to the hippocampal commissure-are the main telencephalic commissures. Supramammilary commissure, posterior commissure, supraoptic commissure and habenular commissure are diencephalic commissures-unknown function, probably related to involuntary eye movements. Commissural agenesis (AWC is absent or impossible to recognize), Alzheimer's Disease (hippocampal commissure may contribute for disease dissemination) and agenesis of corpus callosum are some of the disturbances that involve the telenchephalic commissures. CONCLUSIONS: A comprehensive understanding of the clinic-anatomic correlation is pivotal to understand the pathology and therefore improve our diagnostic accuracy and treatment options, in the background of all patient management.


Subject(s)
Fornix, Brain/anatomy & histology , Nervous System Malformations/diagnosis , Telencephalic Commissures/anatomy & histology , White Matter/anatomy & histology , Fornix, Brain/diagnostic imaging , Humans , Magnetic Resonance Angiography , Nervous System Malformations/pathology , Telencephalic Commissures/diagnostic imaging , White Matter/diagnostic imaging
12.
Int J Obes (Lond) ; 42(5): 1062-1072, 2018 06.
Article in English | MEDLINE | ID: mdl-29453462

ABSTRACT

BACKGROUND: Obesity and insulin resistance/diabetes are important risk factors for cardiovascular diseases and demand safe and efficacious therapeutics. OBJECTIVE: To assess the effects of a new thiazolidine compound-GQ-11-on obesity and insulin resistance induced by a diabetogenic diet in LDL receptor-deficient (LDLr-/-) mice. METHODS: Molecular docking simulations of GQ-11, PPARα and PPARγ structures were performed. Male C57BL/6J LDLr-/- mice fed a diabetogenic diet for 24 weeks were treated with vehicle, GQ-11 or pioglitazone or (20 mg/kg/day) for 28 days by oral gavage. Glucose tolerance test, insulin, HOMA-IR, adipokines (leptin, adiponectin) and the lipid profile were assessed after treatment. Adipose tissue was analysed by X-ray analysis and morphometry; gene and protein expression were evaluated by real-time PCR and western blot, respectively. RESULTS: GQ-11 showed partial agonism to PPARγ and PPARα. In vivo, treatment with GQ-11 ameliorated insulin sensitivity and did not modify subcutaneous adipose tissue and body weight gain. In addition, GQ-11 restored adipokine imbalance induced by a diabetogenic diet and enhanced Glut-4 expression in the adipose tissue. Improved insulin sensitivity was also associated with lower levels of MCP-1 and higher levels of IL-10. Furthermore, GQ-11 reduced triglycerides and VLDL cholesterol and increased HDL-cholesterol by upregulation of Apoa1 and Abca1 gene expression in the liver. CONCLUSION: GQ-11 is a partial/dual PPARα/γ agonist that demonstrates anti-diabetic effects. Additionally, it improves the lipid profile and ameliorates chronic inflammation associated with obesity in atherosclerosis-prone mice.


Subject(s)
Indoles/pharmacology , Obesity/metabolism , Peroxisome Proliferator-Activated Receptors/agonists , Receptors, LDL/metabolism , Thiazolidines/pharmacology , Adipokines/blood , Animals , Body Weight/drug effects , Indoles/chemistry , Inflammation/metabolism , Lipids/blood , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Obese , Receptors, LDL/genetics , Thiazolidines/chemistry
13.
Biochemistry ; 56(25): 3197-3210, 2017 06 27.
Article in English | MEDLINE | ID: mdl-28570817

ABSTRACT

Chemokine ligand 2 (CCL2), also known as monocyte chemoattractant protein 1 (MCP-1), is a chemokine that recruits immune cells to inflammatory sites by interacting with G protein-coupled receptor CCR2. The CCL2/CCR2 axis is also involved in pathological processes such as tumor growth and metastasis and hence is currently considered as an important drug target. CCL2 exists in a dynamic monomer-dimer equilibrium that is modulated by CCR2 binding. We used solution nuclear magnetic resonance (NMR) spectroscopy and molecular dynamics simulations to study the interactions between CCL2 and a sulfopeptide corresponding to the N-terminal sequence of CCR2 (CCR218-31). Peptide binding induced the dissociation of CCL2 into monomers, forming stable CCL2/CCR218-31 complexes. NMR relaxation measurements indicated that residues around the CCR218-31 binding site, which are located at the dimer interface, undergo a complex regime of motions. NMR data were used to construct a three-dimensional structural model of the CCL2/CCR218-31 complex, revealing that CCR218-31 occupies a binding site juxtaposed to the dimer interface, partially replacing monomer-monomer contacts, explaining why CCR218-31 binding weakens the dimer interface and induces dissociation. We found that the main interactions governing receptor binding are highly stable salt bridges with conserved chemokine residues as well as hydrophobic interactions. These data provide new insights into the structure-function relationship of the CCL2-CCR2 interaction and may be helpful for the design of novel antichemotactic agents.


Subject(s)
Chemokine CCL2/chemistry , Chemokine CCL2/metabolism , Protein Interaction Domains and Motifs/drug effects , Receptors, CCR2/chemistry , Receptors, CCR2/metabolism , Binding Sites , Humans , Ligands , Magnetic Resonance Spectroscopy , Molecular Dynamics Simulation , Protein Binding , Protein Conformation , Signal Transduction
14.
J Comput Aided Mol Des ; 31(11): 1009-1019, 2017 Nov.
Article in English | MEDLINE | ID: mdl-29064083

ABSTRACT

Diseases caused by flaviviruses, such as dengue and zika, are globally recognized as major threats. During infection, a critical point in their replicative cycle is the maturation step, which occurs throughout the cellular exocytic pathway. This step is a pH-dependent process that involves the modification of the viral envelope by converting prM (pre-membrane) into M (membrane) proteins with the release of a "pr peptide". After this reaction, the pr peptides remain bound to the viral envelope while the virions cross the acidic trans-Golgi network, and are released only at neutral pH after secretion of the virus particles. Despite this current knowledge, the molecular basis of the flavivirus maturation step is largely unknown. Here, based on the crystal structure of the dengue pr-E complex ("pr peptide" bound to virus envelope protein) and using molecular dynamics simulations, we found that the pH shift from acidic to neutral yields considerable structural changes in the system. Dynamic cross correlation maps and root mean square deviation analyses revealed that the pr-E junction is clearly unstable under neutral pH. Secondary structure analysis also revealed that the fusion loop region, present in the E protein, is sensitive to pH and tends to unstructure at a neutral environment. Moreover, we found that five residues present in the E protein, Gly102, His244, Thr70, Thr68 and Asn67 are critical to confer stability to the pr-E complex while inside the Golgi apparatus. This work brings details about the dynamical behavior of the pr-E system, helps to better understand the flavivirus biology and may also be of use in the development of novel antiviral strategies.


Subject(s)
Dengue Virus/metabolism , Molecular Dynamics Simulation , Viral Envelope Proteins/chemistry , Zika Virus/metabolism , Binding Sites , Humans , Hydrogen-Ion Concentration , Protein Binding , Protein Structure, Secondary , Viral Envelope Proteins/metabolism
15.
Diabetologia ; 59(8): 1760-8, 2016 08.
Article in English | MEDLINE | ID: mdl-27126803

ABSTRACT

AIMS/HYPOTHESIS: Pre-adipocytes and adipocytes are responsive to the acute phase protein serum amyloid A (SAA). The combined effects triggered by SAA encompass an increase in pre-adipocyte proliferation, an induction of TNF-α and IL-6 release and a decrease in glucose uptake in mature adipocytes, strongly supporting a role for SAA in obesity and related comorbidities. This study addressed whether SAA depletion modulates weight gain and insulin resistance induced by a high-fat diet (HFD). METHODS: Male Swiss Webster mice were fed an HFD for 10 weeks under an SAA-targeted antisense oligonucleotide (ASOSAA) treatment in order to evaluate the role of SAA in weight gain. RESULTS: With ASOSAA treatment, mice receiving an HFD did not differ in energy intake when compared with their controls, but were prevented from gaining weight and developing insulin resistance. The phenotype was characterised by a lack of adipose tissue expansion, with low accumulation of epididymal, retroperitoneal and subcutaneous fat content and decreased inflammatory markers, such as SAA3 and toll-like receptor (TLR)-4 expression, as well as macrophage infiltration into the adipose tissue. Furthermore, a metabolic status similar to chow-fed mice counterparts could be observed, with equivalent levels of leptin, adiponectin, IGF-I, SAA, fasting glucose and insulin, and remarkable improvement in glucose and insulin tolerance test profiles. Surprisingly, the expected HFD-induced metabolic endotoxaemia was also prevented by the ASOSAA treatment. CONCLUSIONS/INTERPRETATION: This study provides further evidence of the role of SAA in weight gain and insulin resistance. Moreover, we also suggest that beyond its proliferative and inflammatory effects, SAA is part of the lipopolysaccharide signalling pathway that links inflammation to obesity and insulin resistance.


Subject(s)
Endotoxemia/metabolism , Insulin Resistance/physiology , Serum Amyloid A Protein/metabolism , Weight Gain/physiology , Adiponectin/blood , Adiponectin/metabolism , Animals , Diet, High-Fat/adverse effects , Endotoxemia/blood , Insulin/blood , Insulin/metabolism , Insulin Resistance/genetics , Insulin-Like Growth Factor I/metabolism , Leptin/blood , Leptin/metabolism , Male , Mice , Obesity/blood , Obesity/genetics , Obesity/metabolism , Real-Time Polymerase Chain Reaction , Serum Amyloid A Protein/genetics , Weight Gain/genetics
16.
Cell Immunol ; 300: 18-25, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26632272

ABSTRACT

Myeloperoxidase (MPO) is an important enzyme in the front-line protection against microorganisms. In peripheral blood, it is accepted that MPO is only produced by myeloid-lineage cells. Thus, MPO presence is unexpected in lymphocytes. We showed recently that B1-lymphocytes from mice have MPO. Here, we showed that subsets of human peripheral B, CD4(+) and CD8(+) T lymphocytes express MPO. The content of MPO in lymphocytes was very low compared to neutrophils/monocytes with a preferential distribution in the nucleus and perinuclear region. Also, we performed a MPO mRNA expression analysis from human blood cells derived from microarray raw data publicly available, showing that MPO is modulated in infectious disease. MPO was increased in CD4(+) T lymphocytes from HIV chronic infection and in CD8(+) T lymphocytes from HCV-positive patients. Our study points out MPO as a multifunctional protein due to its subcellular localization and expression modulation in lymphocytes indicating alternative unknown functions for MPO in lymphocytes.


Subject(s)
B-Lymphocytes/enzymology , CD4-Positive T-Lymphocytes/enzymology , CD8-Positive T-Lymphocytes/enzymology , Peroxidase/biosynthesis , B-Lymphocytes/immunology , Blotting, Western , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Cell Separation , Flow Cytometry , HIV Infections/enzymology , HIV Infections/immunology , Hepatitis C/enzymology , Hepatitis C/immunology , Humans , Immunophenotyping , Microscopy, Electron, Transmission , Microscopy, Fluorescence , Oligonucleotide Array Sequence Analysis , Peroxidase/immunology , Real-Time Polymerase Chain Reaction
17.
Pharmacol Res ; 104: 49-60, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26706782

ABSTRACT

Peroxisome proliferator-activated receptor gamma (PPARγ) regulates multiple pathways involved in the pathogenesis of obesity and atherosclerosis. Here, we evaluated the therapeutic potential of GQ-177, a new thiazolidinedione, on diet-induced obesity and atherosclerosis. The intermolecular interaction between PPARγ and GQ-177 was examined by virtual docking and PPAR activation was determined by reporter gene assay identifying GQ-177 as a partial and selective PPARγ agonist. For the evaluation of biological activity of GQ-177, low-density lipoprotein receptor-deficient (LDLr(-/-)) C57/BL6 mice were fed either a high fat diabetogenic diet (diet-induced obesity), or a high fat atherogenic diet, and treated with vehicle, GQ-177 (20mg/kg/day), pioglitazone (20mg/kg/day, diet-induced obesity model) or rosiglitazone (15mg/kg/day, atherosclerosis model) for 28 days. In diet-induced obesity mice, GQ-177 improved insulin sensitivity and lipid profile, increased plasma adiponectin and GLUT4 mRNA in adipose tissue, without affecting body weight, food consumption, fat accumulation and bone density. Moreover, GQ-177 enhanced hepatic mRNA levels of proteins involved in lipid metabolism. In the atherosclerosis mice, GQ-177 inhibited atherosclerotic lesion progression, increased plasma HDL and mRNA levels of PPARγ and ATP-binding cassette A1 in atherosclerotic lesions. GQ-177 acts as a partial PPARγ agonist that improves obesity-associated insulin resistance and dyslipidemia with atheroprotective effects in LDLr(-/-) mice.


Subject(s)
Atherosclerosis/metabolism , Obesity/metabolism , PPAR gamma/agonists , PPAR gamma/metabolism , Receptors, LDL/genetics , Sulfones/pharmacology , Thiazolidinediones/pharmacology , Adiponectin/genetics , Adipose Tissue/drug effects , Adipose Tissue/metabolism , Animals , Aorta, Thoracic/pathology , Atherosclerosis/blood , Atherosclerosis/drug therapy , Atherosclerosis/pathology , Bone Density , Cell Line , Cholesterol, HDL/blood , Fibroblast Growth Factors/genetics , Glucose Transporter Type 4/genetics , Humans , Leptin/genetics , Liver/drug effects , Liver/metabolism , Male , Mice, Knockout , Models, Molecular , Myocardium/metabolism , Obesity/blood , Obesity/drug therapy , Obesity/pathology , Sulfones/therapeutic use , Thiazolidinediones/therapeutic use
18.
Eur Biophys J ; 45(6): 573-80, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27324799

ABSTRACT

The flavivirus non-structural protein 1 (NS1) is a conserved glycoprotein with as yet undefined biological function. This protein dimerizes when inside infected cells or associated to cell membranes but also forms lipid-associated hexamers when secreted to the extracellular space. A single amino acid substitution (P250L) is capable of preventing the dimerization of NS1 resulting in lower virulence and slower virus replication. In this work, based on molecular dynamics simulations of the dengue-2 virus NS1 [Formula: see text]-ladder monomer as a core model, we found that this mutation can induce several conformational changes that importantly affect critical monomer-monomer interactions. Based on additional simulations, we suggest a mechanism by which a highly orchestrated sequence of events propagate the local perturbations around the mutation site towards the dimer interface. The elucidation of such a mechanism could potentially support new strategies for rational production of live-attenuated vaccines and highlights a step forward in the development of novel anti-flavivirus measures.


Subject(s)
Flavivirus , Molecular Dynamics Simulation , Mutation , Protein Multimerization , Viral Nonstructural Proteins/chemistry , Viral Nonstructural Proteins/genetics , Protein Conformation, beta-Strand , Protein Structure, Quaternary
20.
Eur Spine J ; 24 Suppl 4: S465-71, 2015 May.
Article in English | MEDLINE | ID: mdl-24908254

ABSTRACT

INTRODUCTION: Pigmented Villonodular synovitis (PVNS) is a rare vertebral pathology--around 50 reports, only 3 concerning C1-C2 location. CASE REPORT: A 64-year-old man, submitted to a right nephrectomy for a clear cell carcinoma, presented with an asymptomatic osteolytic C1-C2 lesion. Even though the diagnosis of metastatic disease was the most probable, the presence of a solitary lesion without other osseous or systemic localization and the predicted low risk of recurrence imposed a surgical biopsy. A pigmented villonodular synovitis diagnosis was made, a rare vertebral pathology--around 50 reports, only 3 concerning C1-C2 location. No further treatment was assigned precluding the iatrogenic consequences of empirical treatments based on clinical diagnosis with no histopathological support. The patient remains stable at 18 months of follow-up. CONCLUSION: A large differential diagnosis should be made when the typical findings for metastatic disease are absent precluding the iatrogenic consequences of empirical treatments based on clinical diagnosis with no histopathological support.


Subject(s)
Adenocarcinoma, Clear Cell/complications , Cervical Vertebrae , Kidney Neoplasms/complications , Rare Diseases/diagnosis , Synovitis, Pigmented Villonodular/diagnosis , Adenocarcinoma, Clear Cell/diagnosis , Adenocarcinoma, Clear Cell/secondary , Diagnosis, Differential , Humans , Kidney Neoplasms/pathology , Male , Middle Aged , Rare Diseases/complications , Synovitis, Pigmented Villonodular/complications
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