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1.
Respir Res ; 24(1): 124, 2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37143066

RESUMEN

BACKGROUND: People living with HIV (PLWH) are at increased risk of developing Chronic Obstructive Pulmonary Disease (COPD) independent of cigarette smoking. We hypothesized that dysbiosis in PLWH is associated with epigenetic and transcriptomic disruptions in the airway epithelium. METHODS: Airway epithelial brushings were collected from 18 COPD + HIV + , 16 COPD - HIV + , 22 COPD + HIV - and 20 COPD - HIV - subjects. The microbiome, methylome, and transcriptome were profiled using 16S sequencing, Illumina Infinium Methylation EPIC chip, and RNA sequencing, respectively. Multi 'omic integration was performed using Data Integration Analysis for Biomarker discovery using Latent cOmponents. A correlation > 0.7 was used to identify key interactions between the 'omes. RESULTS: The COPD + HIV -, COPD -HIV + , and COPD + HIV + groups had reduced Shannon Diversity (p = 0.004, p = 0.023, and p = 5.5e-06, respectively) compared to individuals with neither COPD nor HIV, with the COPD + HIV + group demonstrating the most reduced diversity. Microbial communities were significantly different between the four groups (p = 0.001). Multi 'omic integration identified correlations between Bacteroidetes Prevotella, genes FUZ, FASTKD3, and ACVR1B, and epigenetic features CpG-FUZ and CpG-PHLDB3. CONCLUSION: PLWH with COPD manifest decreased diversity and altered microbial communities in their airway epithelial microbiome. The reduction in Prevotella in this group was linked with epigenetic and transcriptomic disruptions in host genes including FUZ, FASTKD3, and ACVR1B.


Asunto(s)
Infecciones por VIH , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Disbiosis/genética , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/genética , Perfilación de la Expresión Génica , Epitelio , Infecciones por VIH/epidemiología , Infecciones por VIH/genética
2.
BMC Genomics ; 22(1): 775, 2021 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-34717545

RESUMEN

BACKGROUND: The gut microbiome is a diverse network of bacteria which inhabit our digestive tract and is crucial for efficient cellular metabolism, nutrient absorption, and immune system development. Spinal cord injury (SCI) disrupts autonomic function below the level of injury and can alter the composition of the gut microbiome. Studies in rodent models have shown that SCI-induced bacterial imbalances in the gut can exacerbate the spinal cord damage and impair recovery. In this study we, for the first time, characterized the composition of the gut microbiome in a Yucatan minipig SCI model. We compared the relative abundance of the most dominant bacterial phyla in control samples to those collected from animals who underwent a contusion-compression SCI at the 2nd or 10th Thoracic level. RESULTS: We identify specific bacterial fluctuations that are unique to SCI animals, which were not found in uninjured animals given the same dietary regimen or antibiotic administration. Further, we identified a specific time-frame, "SCI-acute stage", during which many of these bacterial fluctuations occur before returning to "baseline" levels. CONCLUSION: This work presents a dynamic view of the microbiome changes that accompany SCI, establishes a resource for future studies and to understand the changes that occur to gut microbiota after spinal cord injury and may point to a potential therapeutic target for future treatment.


Asunto(s)
Microbioma Gastrointestinal , Traumatismos de la Médula Espinal , Animales , Bacterias , Médula Espinal , Porcinos , Porcinos Enanos
3.
Genome Res ; 27(4): 650-662, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28325850

RESUMEN

Chronic bacterial infections of the lung are the leading cause of morbidity and mortality in cystic fibrosis patients. Tracking bacterial evolution during chronic infections can provide insights into how host selection pressures-including immune responses and therapeutic interventions-shape bacterial genomes. We carried out genomic and phenotypic analyses of 215 serially collected Burkholderia cenocepacia isolates from 16 cystic fibrosis patients, spanning a period of 2-20 yr and a broad range of epidemic lineages. Systematic phenotypic tests identified longitudinal bacterial series that manifested progressive changes in liquid media growth, motility, biofilm formation, and acute insect virulence, but not in mucoidy. The results suggest that distinct lineages follow distinct evolutionary trajectories during lung infection. Pan-genome analysis identified 10,110 homologous gene clusters present only in a subset of strains, including genes restricted to different molecular types. Our phylogenetic analysis based on 2148 orthologous gene clusters from all isolates is consistent with patient-specific clades. This suggests that initial colonization of patients was likely by individual strains, followed by subsequent diversification. Evidence of clonal lineages shared by some patients was observed, suggesting inter-patient transmission. We observed recurrent gene losses in multiple independent longitudinal series, including complete loss of Chromosome III and deletions on other chromosomes. Recurrently observed loss-of-function mutations were associated with decreases in motility and biofilm formation. Together, our study provides the first comprehensive genome-phenome analyses of B. cenocepacia infection in cystic fibrosis lungs and serves as a valuable resource for understanding the genomic and phenotypic underpinnings of bacterial evolution.


Asunto(s)
Infecciones por Burkholderia/microbiología , Burkholderia cenocepacia/genética , Fibrosis Quística/microbiología , Fenotipo , Polimorfismo Genético , Adolescente , Animales , Biopelículas , Infecciones por Burkholderia/complicaciones , Burkholderia cenocepacia/aislamiento & purificación , Burkholderia cenocepacia/patogenicidad , Burkholderia cenocepacia/fisiología , Niño , Preescolar , Fibrosis Quística/complicaciones , Genotipo , Humanos , Pulmón/microbiología , Mariposas Nocturnas/microbiología , Virulencia , Adulto Joven
4.
Cell Commun Signal ; 18(1): 170, 2020 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-33109194

RESUMEN

BACKGROUND: Receptor for advanced glycation end products (RAGE) is a multi-ligand transmembrane receptor of the immunoglobulin superfamily. Lysophosphatidic acid (LPA) is a ligand for RAGE and is involved in physiological and pathophysiological conditions including cancer. However, RAGE-LPA axis is unexplored in lung and mammary cancer. METHODS: RAGE was silenced in A549, MDA MB-231 and MCF7 using RAGE shRNA. For in vitro tumorigenesis, we performed wound healing, colony formation, cell proliferation and invasion assays. Evaluation of expression of oncogenes, EMT markers and downstream signaling molecules was done by using western blot and immunohistochemistry. For subcellular expression of RAGE, immunofluorescence was done. In vivo tumorigenesis was assessed by intraperitoneal injection of cancer cells in nude mice. RESULTS: Here we show RAGE mediated profound increase in proliferation, migration and invasion of lung and mammary cancer cells via LPA in Protein kinase B (PKB) dependent manner. LPA mediated EMT transition is regulated by RAGE. In vivo xenograft results show significance of RAGE in LPA mediated lung and mammary tumor progression, angiogenesis and immune cell infiltration to tumor microenvironment. CONCLUSION: Our results establish the significance and involvement of RAGE in LPA mediated lung and mammary tumor progression and EMT transition via RAGE. RAGE-LPA axis may be a therapeutic target in lung and mammary cancer treatment strategies. Video Abstract.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Neoplasias Pulmonares/patología , Lisofosfolípidos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Transducción de Señal , Microambiente Tumoral , Animales , Neoplasias de la Mama/inmunología , Carcinogénesis/metabolismo , Carcinogénesis/patología , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Transición Epitelial-Mesenquimal , Femenino , Técnicas de Silenciamiento del Gen , Humanos , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/metabolismo , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/patología , Ratones Endogámicos BALB C , Ratones Desnudos , Invasividad Neoplásica , Metástasis de la Neoplasia , Ensayos Antitumor por Modelo de Xenoinjerto
5.
FASEB J ; 32(3): 1196-1206, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29122848

RESUMEN

Excess circulating insulin is associated with obesity in humans and in animal models. However, the physiologic causality of hyperinsulinemia in adult obesity has rightfully been questioned because of the absence of clear evidence that weight loss can be induced by acutely reversing diet-induced hyperinsulinemia. Herein, we describe the consequences of inducible, partial insulin gene deletion in a mouse model in which animals have already been made obese by consuming a high-fat diet. A modest reduction in insulin production/secretion was sufficient to cause significant weight loss within 5 wk, with a specific effect on visceral adipose tissue. This result was associated with a reduction in the protein abundance of the lipodystrophy gene polymerase I and transcript release factor ( Ptrf; Cavin) in gonadal adipose tissue. RNAseq analysis showed that reduced insulin and weight loss also associated with a signature of reduced innate immunity. This study demonstrates that changes in circulating insulin that are too fine to adversely affect glucose homeostasis nonetheless exert control over adiposity.-Page, M. M., Skovsø, S., Cen, H., Chiu, A. P., Dionne, D. A., Hutchinson, D. F., Lim, G. E., Szabat, M., Flibotte, S., Sinha, S., Nislow, C., Rodrigues, B., Johnson, J. D. Reducing insulin via conditional partial gene ablation in adults reverses diet-induced weight gain.


Asunto(s)
Dieta Alta en Grasa/efectos adversos , Eliminación de Gen , Homeostasis , Insulina/fisiología , Obesidad/prevención & control , Aumento de Peso/genética , Adiposidad , Animales , Peso Corporal , Masculino , Ratones , Ratones Noqueados , Obesidad/etiología , Obesidad/patología
6.
PLoS Genet ; 12(9): e1006275, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27588687

RESUMEN

The emergence and prevalence of drug resistance demands streamlined strategies to identify drug resistant variants in a fast, systematic and cost-effective way. Methods commonly used to understand and predict drug resistance rely on limited clinical studies from patients who are refractory to drugs or on laborious evolution experiments with poor coverage of the gene variants. Here, we report an integrative functional variomics methodology combining deep sequencing and a Bayesian statistical model to provide a comprehensive list of drug resistance alleles from complex variant populations. Dihydrofolate reductase, the target of methotrexate chemotherapy drug, was used as a model to identify functional mutant alleles correlated with methotrexate resistance. This systematic approach identified previously reported resistance mutations, as well as novel point mutations that were validated in vivo. Use of this systematic strategy as a routine diagnostics tool widens the scope of successful drug research and development.


Asunto(s)
Resistencia a Antineoplásicos/genética , Neoplasias/tratamiento farmacológico , Tetrahidrofolato Deshidrogenasa/metabolismo , Alelos , Teorema de Bayes , Antagonistas del Ácido Fólico/uso terapéutico , Humanos , Metotrexato/uso terapéutico , Mutación , Neoplasias/genética , Tetrahidrofolato Deshidrogenasa/genética
7.
PLoS Pathog ; 12(4): e1005576, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-27124727

RESUMEN

Many bacterial species actively take up and recombine homologous DNA into their genomes, called natural competence, a trait that offers a means to identify the genetic basis of naturally occurring phenotypic variation. Here, we describe "transformed recombinant enrichment profiling" (TREP), in which natural transformation is used to generate complex pools of recombinants, phenotypic selection is used to enrich for specific recombinants, and deep sequencing is used to survey for the genetic variation responsible. We applied TREP to investigate the genetic architecture of intracellular invasion by the human pathogen Haemophilus influenzae, a trait implicated in persistence during chronic infection. TREP identified the HMW1 adhesin as a crucial factor. Natural transformation of the hmw1 operon from a clinical isolate (86-028NP) into a laboratory isolate that lacks it (Rd KW20) resulted in ~1,000-fold increased invasion into airway epithelial cells. When a distinct recipient (Hi375, already possessing hmw1 and its paralog hmw2) was transformed by the same donor, allelic replacement of hmw2AHi375 by hmw1A86-028NP resulted in a ~100-fold increased intracellular invasion rate. The specific role of hmw1A86-028NP was confirmed by mutant and western blot analyses. Bacterial self-aggregation and adherence to airway cells were also increased in recombinants, suggesting that the high invasiveness induced by hmw1A86-028NP might be a consequence of these phenotypes. However, immunofluorescence results found that intracellular hmw1A86-028NP bacteria likely invaded as groups, instead of as individual bacterial cells, indicating an emergent invasion-specific consequence of hmw1A-mediated self-aggregation.


Asunto(s)
Adhesinas Bacterianas/genética , Perfilación de la Expresión Génica/métodos , Infecciones por Haemophilus/microbiología , Western Blotting , Células Epiteliales/microbiología , Haemophilus influenzae/genética , Humanos , Espacio Intracelular/microbiología , Microscopía Fluorescente , Reacción en Cadena de la Polimerasa
8.
Respir Res ; 19(1): 140, 2018 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-30053882

RESUMEN

BACKGROUND: Persons living with human immunodeficiency virus (PLWH) face an increased burden of chronic obstructive pulmonary disease (COPD). Repeated pulmonary infections, antibiotic exposures, and immunosuppression may contribute to an altered small airway epithelium (SAE) microbiome. METHODS: SAE cells were collected from 28 PLWH and 48 HIV- controls through bronchoscopic cytologic brushings. DNA extracted from SAE cells was subjected to 16S rRNA amplification and sequencing. Comparisons of alpha and beta diversity between HIV+ and HIV- groups were performed and key operational taxonomic units (OTUs) distinguishing the two groups were identified using the Boruta feature selection after Random Forest Analysis. RESULTS: PLWH demonstrated significantly reduced Shannon diversity compared with HIV- volunteers (1.82 ± 0.10 vs. 2.20 ± 0.073, p = 0.0024). This was primarily driven by a reduction in bacterial richness (23.29 ± 2.75 for PLWH and 46.04 ± 3.716 for HIV-, p < 0.0001). Phyla distribution was significantly altered among PLWH, with an increase in relative abundance of Proteobacteria (p = 0.0003) and a decrease in Bacteroidetes (p = 0.0068) and Firmicutes (p = 0.0002). Six discriminative OTUs were found to distinguish PLWH from HIV- volunteers, aligning to Veillonellaceae, Fusobacterium, Verrucomicrobiaceae, Prevotella, Veillonella, and Campylobacter. CONCLUSIONS: Compared to HIV- controls, PLWH's SAE microbiome is marked by reduced bacterial diversity and richness with significant differences in community composition.


Asunto(s)
Infecciones por VIH/microbiología , Microbiota/fisiología , Enfermedad Pulmonar Obstructiva Crónica/microbiología , Mucosa Respiratoria/microbiología , Mucosa Respiratoria/fisiología , Anciano , Broncoscopía/métodos , Estudios de Cohortes , Femenino , Infecciones por VIH/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología
10.
BMC Pulm Med ; 16(1): 142, 2016 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-27829448

RESUMEN

BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) is an important comorbidity in patients living with human immunodeficiency virus (HIV). Previous bacterial microbiome studies have shown increased abundance of specific bacterium, like Tropheryma whipplei, and no overall community differences. However, the host response to the lung microbiome is unknown in patients infected with HIV. METHODS: Two bronchial brush samples were obtained from 21 HIV-infected patients. One brush was used for bacterial microbiome analysis using the Illumina MiSeqTM platform, while the other was used to evaluate gene expression patterns of the host using the Affymetrix Human Gene ST 2.0 array. Weighted gene co-expression network analysis was used to determine the relationship between the bacterial microbiome and host gene expression response. RESULTS: The Shannon Diversity was inversely related to only one gene expression module (p = 0.02); whereas evenness correlated with five different modules (p ≤ 0.05). After FDR correction only the Firmicutes phylum was significantly correlated with any modules (FDR < 0.05). These modules were enriched for cilia, transcription regulation, and immune response. Specific operational taxonomic units (OTUs), such as OTU4 (Pasteurellaceae), were able to distinguish HIV patients with and without COPD and severe emphysema. CONCLUSION: These data support the hypothesis that the bacterial microbiome in HIV lungs is associated with specific host immune responses. Whether or not these responses are also seen in non-HIV infected individuals needs to be addressed in future studies.


Asunto(s)
Infecciones por VIH/complicaciones , Pulmón/microbiología , Microbiota , Enfermedad Pulmonar Obstructiva Crónica/microbiología , Adulto , Anciano , Bacterias/clasificación , Células Epiteliales/citología , Femenino , Expresión Génica , Infecciones por VIH/microbiología , Humanos , Pulmón/citología , Masculino , Análisis por Micromatrices , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/inmunología , ARN Ribosómico 16S/genética , Tomografía Computarizada por Rayos X
11.
Mol Microbiol ; 88(6): 1106-19, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23663205

RESUMEN

Many bacteria are naturally competent, able to bind and take up DNA from their extracellular environment. This DNA can serve as a significant source of nutrients, in addition to providing genetic material for recombination. The regulation of competence in several model organisms highlights the importance of this nutritional function, although it has often been overlooked. Natural competence is induced by starvation in Haemophilus influenzae, the model for competence regulation in the gamma-proteobacteria. This induction depends on the activation of the global metabolic regulator CRP, which occurs upon depletion of phosphotransferase sugars. In this work, we show that the depletion of purine nucleotides under competence-inducing conditions activates the CRP-dependent competence-specific regulator Sxy. Depletion of extra- or intra-cellular purine nucleotides activates Sxy translation, while high levels inhibit it. This is modulated by the stem structure formed by sxy mRNA. The exact mechanism by which the nucleotide depletion signal is transduced is unclear, but it does not involve direct binding of purine intermediates to the sxy stem, and does not require Hfq or competence proteins. Similar regulation occurs in the relatives of H. influenzae, Actinobacillus pneumoniae and A. suis, confirming the importance of processes enabling competent bacteria to exploit the abundant DNA in their environments.


Asunto(s)
Proteínas Bacterianas/biosíntesis , Competencia de la Transformación por ADN , Regulación Bacteriana de la Expresión Génica , Haemophilus influenzae/genética , Haemophilus influenzae/metabolismo , Biosíntesis de Proteínas , Nucleótidos de Purina/metabolismo , Transactivadores/biosíntesis , Proteína Receptora de AMP Cíclico/metabolismo
12.
iScience ; 26(5): 106525, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37250326

RESUMEN

Peroxisome proliferator-activated receptor gamma (PPARγ) is a nuclear receptor central in the regulation of key cellular processes including cell metabolism, tissue differentiation, and regulation of the immune system. PPARγ is required for normal differentiation of the urothelium and is thought to be an essential driver of the luminal subtype of bladder cancer. However, the molecular components that regulate PPARG gene expression in bladder cancer remain unclear. Here, we developed an endogenous PPARG reporter system in luminal bladder cancer cells and performed genome-wide CRISPR knockout screening to identify bona fide regulators of PPARG gene expression. Functional validation of the dataset confirmed GATA3, SPT6, and the cohesin complex components SMC1A, and RAD21, as permissive upstream positive regulators of PPARG gene expression in luminal bladder cancer. In summary, this work provides a resource and biological insights to aid our understanding of PPARG regulation in bladder cancer.

13.
J Bacteriol ; 194(19): 5245-54, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22821979

RESUMEN

Natural competence is the ability of bacteria to actively take up extracellular DNA. This DNA can recombine with the host chromosome, transforming the host cell and altering its genotype. In Haemophilus influenzae, natural competence is induced by energy starvation and the depletion of nucleotide pools. This induces a 26-gene competence regulon (Sxy-dependent cyclic AMP receptor protein [CRP-S] regulon) whose expression is controlled by two regulators, CRP and Sxy. The role of most of the CRP-S genes in DNA uptake and transformation is not known. We have therefore created in-frame deletions of each CRP-S gene and studied their competence phenotypes. All but one gene (ssb) could be deleted. Although none of the remaining CRP-S genes were required for growth in rich medium or survival under starvation conditions, DNA uptake and transformation were abolished or reduced in most of the mutants. Seventeen genes were absolutely required for transformation, with 14 of these genes being specifically required for the assembly and function of the type IV pilus DNA uptake machinery. Only five genes were dispensable for both competence and transformation. This is the first competence regulon for which all genes have been mutationally characterized.


Asunto(s)
Proteínas Bacterianas/metabolismo , Haemophilus influenzae/metabolismo , Receptores de AMP Cíclico/metabolismo , Transactivadores/metabolismo , Transformación Bacteriana/fisiología , Proteínas Bacterianas/genética , Cromosomas Bacterianos , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , Eliminación de Gen , Regulación Bacteriana de la Expresión Génica/fisiología , Haemophilus influenzae/genética , Familia de Multigenes , Receptores de AMP Cíclico/genética , Regulón/genética , Transactivadores/genética
14.
Appl Environ Microbiol ; 78(14): 4914-22, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22582057

RESUMEN

Gallibacterium anatis is a pathogen of poultry. Very little is known about its genetics and pathogenesis. To enable the study of gene function in G. anatis, we have established methods for transformation and targeted mutagenesis. The genus Gallibacterium belongs to the Pasteurellaceae, a group with several naturally transformable members, including Haemophilus influenzae. Bioinformatics analysis identified G. anatis homologs of the H. influenzae competence genes, and natural competence was induced in G. anatis by the procedure established for H. influenzae: transfer from rich medium to the starvation medium M-IV. This procedure gave reproducibly high transformation frequencies with G. anatis chromosomal DNA and with linearized plasmid DNA carrying G. anatis sequences. Both DNA types integrated into the G. anatis chromosome by homologous recombination. Targeted mutagenesis gave transformation frequencies of >2 × 10(-4) transformants CFU(-1). Transformation was also efficient with circular plasmid containing no G. anatis DNA; this resulted in the establishment of a self-replicating plasmid. Nine diverse G. anatis strains were found to be naturally transformable by this procedure, suggesting that natural competence is common and the M-IV transformation procedure widely applicable for this species. The G. anatis genome is only slightly enriched for the uptake signal sequences identified in other pasteurellaceaen genomes, but G. anatis did preferentially take up its own DNA over that of Escherichia coli. Transformation by electroporation was not effective for chromosomal integration but could be used to introduce self-replicating plasmids. The findings described here provide important tools for the genetic manipulation of G. anatis.


Asunto(s)
Pasteurellaceae/genética , Transformación Bacteriana/genética , Cromosomas Bacterianos/genética , ADN Bacteriano/análisis , ADN Bacteriano/genética , Datos de Secuencia Molecular , Pasteurellaceae/crecimiento & desarrollo , Pasteurellaceae/fisiología , Plásmidos/genética , Análisis de Secuencia de ADN
15.
Nat Commun ; 13(1): 735, 2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35136059

RESUMEN

Insulin receptor (Insr) protein is present at higher levels in pancreatic ß-cells than in most other tissues, but the consequences of ß-cell insulin resistance remain enigmatic. Here, we use an Ins1cre knock-in allele to delete Insr specifically in ß-cells of both female and male mice. We compare experimental mice to Ins1cre-containing littermate controls at multiple ages and on multiple diets. RNA-seq of purified recombined ß-cells reveals transcriptomic consequences of Insr loss, which differ between female and male mice. Action potential and calcium oscillation frequencies are increased in Insr knockout ß-cells from female, but not male mice, whereas only male ßInsrKO islets have reduced ATP-coupled oxygen consumption rate and reduced expression of genes involved in ATP synthesis. Female ßInsrKO and ßInsrHET mice exhibit elevated insulin release in ex vivo perifusion experiments, during hyperglycemic clamps, and following i.p. glucose challenge. Deletion of Insr does not alter ß-cell area up to 9 months of age, nor does it impair hyperglycemia-induced proliferation. Based on our data, we adapt a mathematical model to include ß-cell insulin resistance, which predicts that ß-cell Insr knockout improves glucose tolerance depending on the degree of whole-body insulin resistance. Indeed, glucose tolerance is significantly improved in female ßInsrKO and ßInsrHET mice compared to controls at 9, 21 and 39 weeks, and also in insulin-sensitive 4-week old males. We observe no improved glucose tolerance in older male mice or in high fat diet-fed mice, corroborating the prediction that global insulin resistance obscures the effects of ß-cell specific insulin resistance. The propensity for hyperinsulinemia is associated with mildly reduced fasting glucose and increased body weight. We further validate our main in vivo findings using an Ins1-CreERT transgenic line and find that male mice have improved glucose tolerance 4 weeks after tamoxifen-mediated Insr deletion. Collectively, our data show that ß-cell insulin resistance in the form of reduced ß-cell Insr contributes to hyperinsulinemia in the context of glucose stimulation, thereby improving glucose homeostasis in otherwise insulin sensitive sex, dietary and age contexts.


Asunto(s)
Diabetes Mellitus Tipo 2/genética , Hiperinsulinismo/genética , Resistencia a la Insulina/genética , Células Secretoras de Insulina/metabolismo , Receptor de Insulina/genética , Animales , Conjuntos de Datos como Asunto , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Femenino , Técnicas de Sustitución del Gen , Técnicas de Inactivación de Genes , Glucosa/metabolismo , Humanos , Hiperinsulinismo/sangre , Hiperinsulinismo/metabolismo , Hiperinsulinismo/patología , Insulina/sangre , Insulina/metabolismo , Células Secretoras de Insulina/patología , Masculino , Ratones , Ratones Transgénicos , RNA-Seq , Receptor de Insulina/deficiencia , Factores Sexuales
16.
Cell Rep ; 34(9): 108809, 2021 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-33657371

RESUMEN

Muscle differentiation is a multifaceted and tightly controlled process required for the formation of skeletal muscle fibers. Satellite cells are the direct cellular contributors to muscle repair in injuries or disorders. Here, we show that autotaxin (Atx) expression and activity is required for satellite cell differentiation. Conditional ablation of Atx or its pharmacological inhibition impairs muscle repair. Mechanistically, we identify LPAR1 as the key receptor in Atx-LPA signaling. Myogenic gene array and pathway analysis identified that Atx-LPA signaling activates ribosomal protein S6 kinase (S6K), an mTOR-dependent master regulator of muscle cell growth via LPAR1. Furthermore, Atx transgenic mice show muscle hypertrophic effects and accelerated regeneration. Intramuscular injections of Atx/LPA show muscle hypertrophy. In addition, the regulatory effects of Atx on differentiation are conserved in human myoblasts. This study identifies Atx as a critical master regulator in murine and human muscles, identifying a promising extracellular ligand in muscle formation, regeneration, and hypertrophy.


Asunto(s)
Lisofosfolípidos/metabolismo , Desarrollo de Músculos , Músculo Esquelético/metabolismo , Hidrolasas Diéster Fosfóricas/metabolismo , Receptores del Ácido Lisofosfatídico/metabolismo , Regeneración , Células Satélite del Músculo Esquelético/metabolismo , Animales , Línea Celular , Femenino , Regulación de la Expresión Génica , Humanos , Hipertrofia , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Músculo Esquelético/patología , Músculo Esquelético/fisiopatología , Hidrolasas Diéster Fosfóricas/genética , Receptores del Ácido Lisofosfatídico/genética , Proteínas Quinasas S6 Ribosómicas/metabolismo , Células Satélite del Músculo Esquelético/patología , Transducción de Señal , Crecimiento del Músculo Esquelético , Serina-Treonina Quinasas TOR/metabolismo
17.
Cell Death Dis ; 12(11): 1012, 2021 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-34711805

RESUMEN

Melanoma originates from melanin-producing cells called melanocytes. Melanoma poses a great risk because of its rapid ability to spread and invade new organs. Cellular metastasis involves alteration in the gene expression profile and their transformation from epithelial to mesenchymal state. Despite of several advances, metastatic melanoma being a key cause of therapy failure and mortality remains poorly understood. p32 has been found to be involved in various physiological and pathophysiological conditions. However, the role of p32 in melanoma progression and metastasis remains underexplored. Here, we identify the role of p32 in the malignancy of both murine and human melanoma. p32 knockdown leads to reduced cell proliferation, migration, and invasion in murine and human melanoma cells. Furthermore, p32 promotes in vitro tumorigenesis, inducing oncogenes and EMT markers. Mechanistically, we show p32 regulates tumorigenic and metastatic properties through the Akt/PKB signaling pathway in both murine and human melanoma. Furthermore, p32 silencing attenuates melanoma tumor progression and lung metastasis in vivo, modulating the tumor microenvironment by inhibiting the angiogenesis, infiltration of macrophages, and leukocytes in mice. Taken together, our findings identify that p32 drives melanoma progression, metastasis, and regulates the tumor microenvironment. p32 can be a target of a novel therapeutic approach in the regulation of melanoma progression and metastasis.


Asunto(s)
Proteínas Portadoras/efectos adversos , Transición Epitelial-Mesenquimal/genética , Melanoma/genética , Proteínas Mitocondriales/efectos adversos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Movimiento Celular , Proliferación Celular , Progresión de la Enfermedad , Humanos , Melanoma/mortalidad , Melanoma/fisiopatología , Ratones , Metástasis de la Neoplasia , Transducción de Señal , Análisis de Supervivencia , Transfección , Microambiente Tumoral
18.
J Fungi (Basel) ; 7(9)2021 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-34575761

RESUMEN

The experimental evolution of microorganisms exposed to extreme conditions can provide insight into cellular adaptation to stress. Typically, stress-sensitive species are exposed to stress over many generations and then examined for improvements in their stress tolerance. In contrast, when starting with an already stress-tolerant progenitor there may be less room for further improvement, it may still be able to tweak its cellular machinery to increase extremotolerance, perhaps at the cost of poorer performance under non-extreme conditions. To investigate these possibilities, a strain of extremely halotolerant black yeast Hortaea werneckii was grown for over seven years through at least 800 generations in a medium containing 4.3 M NaCl. Although this salinity is well above the optimum (0.8-1.7 M) for the species, the growth rate of the evolved H. werneckii did not change in the absence of salt or at high concentrations of NaCl, KCl, sorbitol, or glycerol. Other phenotypic traits did change during the course of the experimental evolution, including fewer multicellular chains in the evolved strains, significantly narrower cells, increased resistance to caspofungin, and altered melanisation. Whole-genome sequencing revealed the occurrence of multiple aneuploidies during the experimental evolution of the otherwise diploid H. werneckii. A significant overrepresentation of several gene groups was observed in aneuploid regions. Taken together, these changes suggest that long-term growth at extreme salinity led to alterations in cell wall and morphology, signalling pathways, and the pentose phosphate cycle. Although there is currently limited evidence for the adaptive value of these changes, they offer promising starting points for future studies of fungal halotolerance.

19.
J Bacteriol ; 192(9): 2414-23, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20207760

RESUMEN

Clinical isolates of the porcine pathogen Actinobacillus pleuropneumoniae often form adherent colonies on agar plates due to expression of an operon, pgaABCD, encoding a poly-beta-1,6-N-acetyl-D-glucosamine (PGA) extracellular matrix. The adherent colony phenotype, which correlates with the ability to form biofilms on the surfaces of polystyrene plates, is lost following serial passage in broth culture, and repeated passage of the nonadherent variants on solid media does not result in reversion to the adherent colony phenotype. In order to investigate the regulation of PGA expression and biofilm formation in A. pleuropneumoniae, we screened a bank of transposon mutants of the nonadherent serovar 1 strain S4074(T) and identified mutations in two genes, rseA and hns, which resulted in the formation of the adherent colony phenotype. In other bacteria, including the Enterobacteriaceae, H-NS acts as a global gene regulator, and RseA is a negative regulator of the extracytoplasmic stress response sigma factor sigma(E). Transcription profiling of A. pleuropneumoniae rseA and hns mutants revealed that both sigma(E) and H-NS independently regulate expression of the pga operon. Transcription of the pga operon is initiated from a sigma(E) promoter site in the absence of H-NS, and upregulation of sigma(E) is sufficient to displace H-NS, allowing transcription to proceed. In A. pleuropneumoniae, H-NS does not act as a global gene regulator but rather specifically regulates biofilm formation via repression of the pga operon. Positive regulation of the pga operon by sigma(E) indicates that biofilm formation is part of the extracytoplasmic stress response in A. pleuropneumoniae.


Asunto(s)
Proteínas Bacterianas/metabolismo , Biopelículas , Proteínas de Unión al ADN/metabolismo , Regulación Bacteriana de la Expresión Génica , Operón/genética , Factor sigma/metabolismo , Actinobacillus pleuropneumoniae/genética , Actinobacillus pleuropneumoniae/crecimiento & desarrollo , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Biopelículas/crecimiento & desarrollo , Proteínas de Unión al ADN/genética , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido , Factor sigma/genética , beta-Glucanos/metabolismo
20.
J Pers Med ; 11(1)2020 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-33374349

RESUMEN

In this study 180 patients were consented and enrolled for pharmacogenomic testing based on current antidepressant/antipsychotic usage. Samples from patients were genotyped by PCR, MassArray, and targeted next generation sequencing. We also conducted a quantitative, frequency-based analysis of participants' perceptions using simple surveys. Pharmacogenomic information, including medication changes and altered dosing recommendations were returned to the pharmacists and used to direct patient therapy. Overwhelmingly, patients perceived pharmacists/pharmacies as an appropriate healthcare provider to deliver pharmacogenomic services. In total, 81 medication changes in 33 unique patients, representing 22% of all genotyped participants were recorded. We performed a simple drug cost analysis and found that medication adjustments and dosing changes across the entire cohort added $24.15CAD per patient per year for those that required an adjustment. Comparing different platforms, we uncovered a small number, 1.7%, of genotype discrepancies. We conclude that: (1). Pharmacists are competent providers of pharmacogenomic services. (2). The potential reduction in adverse drug responses and optimization of drug selection and dosing comes at a minimal cost to the health care system. (3). Changes in drug therapy, based on PGx tests, result in inconsequential changes in annual drug therapy cost with small cost increases just as likely as costs savings. (4). Pharmacogenomic services offered by pharmacists are ready for wide commercial implementation.

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