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1.
Nat Chem Biol ; 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38538923

RESUMEN

Telomere dysfunction is intricately linked to the aging process and stands out as a prominent cancer hallmark. Here we demonstrate that telomerase activity is differentially regulated in cancer and normal cells depending on the expression status of fructose-1,6-bisphosphatase 1 (FBP1). In FBP1-expressing cells, FBP1 directly interacts with and dephosphorylates telomerase reverse transcriptase (TERT) at Ser227. Dephosphorylated TERT fails to translocate into the nucleus, leading to the inhibition of telomerase activity, reduction in telomere lengths, enhanced senescence and suppressed tumor cell proliferation and growth in mice. Lipid nanoparticle-mediated delivery of FBP1 mRNA inhibits liver tumor growth. Additionally, FBP1 expression levels inversely correlate with TERT pSer227 levels in renal and hepatocellular carcinoma specimens and with poor prognosis of the patients. These findings demonstrate that FBP1 governs cell immortality through its protein phosphatase activity and uncover a unique telomerase regulation in tumor cells attributed to the downregulation or deficiency of FBP1 expression.

2.
Circ Res ; 134(3): 252-265, 2024 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-38166470

RESUMEN

BACKGROUND: Intracellular Ca2+ cycling determines myocardial contraction and relaxation in response to physiological demands. SERCA2a (sarcoplasmic/endoplasmic reticulum Ca2+-ATPase 2a) is responsible for the sequestration of cytosolic Ca2+ into intracellular stores during cardiac relaxation, and its activity is reversibly inhibited by PLN (phospholamban). However, the regulatory hierarchy of SERCA2a activity remains unclear. METHODS: Cardiomyocyte-specific ZBTB20 knockout mice were generated by crossing ZBTB20flox mice with Myh6-Cre mice. Echocardiography, blood pressure measurements, Langendorff perfusion, histological analysis and immunohistochemistry, quantitative reverse transcription-PCR, Western blot analysis, electrophysiological measurements, and chromatin immunoprecipitation assay were performed to clarify the phenotype and elucidate the molecular mechanisms. RESULTS: Specific ablation of ZBTB20 in cardiomyocyte led to a significant increase in basal myocardial contractile parameters both in vivo and in vitro, accompanied by an impairment in cardiac reserve and exercise capacity. Moreover, the cardiomyocytes lacking ZBTB20 showed an increase in sarcoplasmic reticular Ca2+ content and exhibited a remarkable enhancement in both SERCA2a activity and electrically stimulated contraction. Mechanistically, PLN expression was dramatically reduced in cardiomyocytes at the mRNA and protein levels by ZBTB20 deletion or silencing, and PLN overexpression could largely restore the basal contractility in ZBTB20-deficient cardiomyocytes. CONCLUSIONS: These data point to ZBTB20 as a fine-tuning modulator of PLN expression and SERCA2a activity, thereby offering new perspective on the regulation of basal contractility in the mammalian heart.


Asunto(s)
Miocardio , Retículo Sarcoplasmático , Animales , Ratones , Calcio/metabolismo , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo , Mamíferos , Ratones Noqueados , Contracción Miocárdica/fisiología , Miocardio/metabolismo , Miocitos Cardíacos/metabolismo , Retículo Sarcoplasmático/metabolismo , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/genética , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/metabolismo
3.
Cell ; 146(5): 772-84, 2011 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-21871655

RESUMEN

T cell differentiation into distinct functional effector and inhibitory subsets is regulated, in part, by the cytokine environment present at the time of antigen recognition. Here, we show that hypoxia-inducible factor 1 (HIF-1), a key metabolic sensor, regulates the balance between regulatory T cell (T(reg)) and T(H)17 differentiation. HIF-1 enhances T(H)17 development through direct transcriptional activation of RORγt and via tertiary complex formation with RORγt and p300 recruitment to the IL-17 promoter, thereby regulating T(H)17 signature genes. Concurrently, HIF-1 attenuates T(reg) development by binding Foxp3 and targeting it for proteasomal degradation. Importantly, this regulation occurs under both normoxic and hypoxic conditions. Mice with HIF-1α-deficient T cells are resistant to induction of T(H)17-dependent experimental autoimmune encephalitis associated with diminished T(H)17 and increased T(reg) cells. These findings highlight the importance of metabolic cues in T cell fate determination and suggest that metabolic modulation could ameliorate certain T cell-based immune pathologies.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Linfocitos T Reguladores/citología , Células Th17/citología , Animales , Secuencia de Bases , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/metabolismo , Factores de Transcripción Forkhead/metabolismo , Humanos , Factor 1 Inducible por Hipoxia/metabolismo , Interleucina-17/genética , Interleucina-17/inmunología , Células Jurkat , Ratones , Datos de Secuencia Molecular , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Factor de Transcripción STAT3/metabolismo , Alineación de Secuencia , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Células Th17/inmunología , Células Th17/metabolismo , Factores de Transcripción p300-CBP/metabolismo
4.
Immunity ; 45(1): 83-93, 2016 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-27438767

RESUMEN

Regulatory T (Treg) cells are important in maintaining self-tolerance and immune homeostasis. The Treg cell transcription factor Foxp3 works in concert with other co-regulatory molecules, including Eos, to determine the transcriptional signature and characteristic suppressive phenotype of Treg cells. Here, we report that the inflammatory cytokine interleukin-6 (IL-6) actively repressed Eos expression through microRNA-17 (miR-17). miR-17 expression increased in Treg cells in the presence of IL-6, and its expression negatively correlated with that of Eos. Treg cell suppressive activity was diminished upon overexpression of miR-17 in vitro and in vivo, which was mitigated upon co-expression of an Eos mutant lacking miR-17 target sites. Also, RNAi of miR-17 resulted in enhanced suppressive activity. Ectopic expression of miR-17 imparted effector-T-cell-like characteristics to Treg cells via the de-repression of genes encoding effector cytokines. Thus, miR-17 provides a potent layer of Treg cell control through targeting Eos and additional Foxp3 co-regulators.


Asunto(s)
Proteínas Portadoras/metabolismo , Colitis/inmunología , Interleucina-6/metabolismo , MicroARNs/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Linfocitos T Reguladores/inmunología , Animales , Proteínas Portadoras/genética , Células Cultivadas , Proteínas de Unión al ADN , Modelos Animales de Enfermedad , Factores de Transcripción Forkhead/metabolismo , Humanos , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Interleucina-6/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , MicroARNs/genética , Proteínas del Tejido Nervioso/genética , Autotolerancia
5.
Kidney Int ; 105(3): 442-444, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38388145

RESUMEN

This commentary provides an analysis of the study by Fu et al. in Kidney International, which employs 3 administrative databases to investigate the hyperkalemia protective effects of sodium-glucose cotransporter-2 inhibitors, glucagon-like peptide-1 receptor agonists, and dipeptidyl peptidase-4 inhibitors. It emphasizes the methodological approach, notably the use of a fixed-effect model to aggregate pairwise comparisons from 3 data sets. In addition, we explored the broader cardiorenal and potential nonrenal benefits of these drug classes, underscoring the imperative for continued research in this domain.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Inhibidores del Cotransportador de Sodio-Glucosa 2/efectos adversos , Hipoglucemiantes/efectos adversos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Agonistas Receptor de Péptidos Similares al Glucagón , Inhibidores de la Dipeptidil-Peptidasa IV/efectos adversos , Receptor del Péptido 1 Similar al Glucagón
6.
Hum Mol Genet ; 31(10): 1560-1573, 2022 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-34957500

RESUMEN

Metabolic reprogramming is a potential treatment strategy for autosomal dominant polycystic kidney disease (ADPKD). Metformin has been shown to inhibit the early stages of cyst formation in animal models. However, metformin can lead to lactic acidosis in diabetic patients with advanced chronic kidney disease, and its efficacy in ADPKD is still not fully understood. Here, we investigated the effect of metformin in an established hypomorphic mouse model of PKD that presents stable and heritable knockdown of Pkd1. The Pkd1 miRNA transgenic mice of both genders were randomized to receive metformin or saline injections. Metformin was administrated through daily intraperitoneal injection from postnatal day 35 for 4 weeks. Unexpectedly, metformin treatment at a concentration of 150 mg/kg increased disease severity, including kidney-to-body weight ratio, cystic index and plasma BUN levels, and was associated with increased renal tubular cell proliferation and plasma lactate levels. Functional enrichment analysis for cDNA microarrays from kidney samples revealed significant enrichment of several pro-proliferative pathways including ß-catenin, hypoxia-inducible factor-1α, protein kinase Cα and Notch signaling pathways in the metformin-treated mutant mice. The plasma metformin concentrations were still within the recommended therapeutic range for type 2 diabetic patients. Short-term metformin treatment in a second Pkd1 hypomorphic model (Pkd1RC/RC) was however neutral. These results demonstrate that metformin may exacerbate late-stage cyst growth associated with the activation of lactate-related signaling pathways in Pkd1 deficiency. Our findings indicate that using metformin in the later stage of ADPKD might accelerate disease progression and call for the cautious use of metformin in these patients.


Asunto(s)
Quistes , Metformina , Riñón Poliquístico Autosómico Dominante , Animales , Quistes/metabolismo , Modelos Animales de Enfermedad , Femenino , Riñón/metabolismo , Ácido Láctico/metabolismo , Masculino , Metformina/metabolismo , Metformina/farmacología , Ratones , Ratones Transgénicos , Enfermedades Renales Poliquísticas , Riñón Poliquístico Autosómico Dominante/tratamiento farmacológico , Riñón Poliquístico Autosómico Dominante/genética , Riñón Poliquístico Autosómico Dominante/metabolismo , Canales Catiónicos TRPP/genética , Canales Catiónicos TRPP/metabolismo
7.
Antimicrob Agents Chemother ; : e0058724, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39240098

RESUMEN

The burgeoning emergence of drug-resistant Helicobacter pylori strains poses a significant challenge to the clinical success of eradication therapies and is primarily attributed to mutations within drug-targeting genes that lead to antibiotic resistance. This study investigated the effect of high salt conditions on the occurrence of drug-resistance mutations in H. pylori. We found that high salt condition significantly amplifies the frequency of drug resistance mutations in H. pylori. This can be chiefly attributed to our discovery indicating that high salt concentration results in elevated reactive oxygen species (ROS) levels, initiating DNA damage within H. pylori. Mechanistically, high salt condition suppresses lipopolysaccharide (LPS) synthesis gene expression, inducing alterations in the LPS structure and escalating outer membrane permeability. This disruption of LPS synthesis attenuates the expression and activity of SodB, facilitates increased ROS levels, and consequently increases the drug resistance mutation frequency. Impairing LPS synthesis engenders a reduction in intracellular iron levels, leading to diminished holo-Fur activity and increased apo-Fur activity, which represses the expression of SodB directly. Our findings suggest a correlation between high salt intake and the emergence of drug resistance in the human pathogen H. pylori, implying that dietary choices affect the risk of emergence of antimicrobial resistance.IMPORTANCEDrug resistance mutations mainly contribute to the emergence of clinical antibiotic-resistant Helicobacter pylori, a bacterium linked to stomach ulcers and cancer. In this study, we explored how elevated salt conditions influence the emergence of drug resistance in H. pylori. We demonstrate that H. pylori exhibits an increased antibiotic resistance mutation frequency when exposed to a high salt environment. We observed an increase in reactive oxygen species (ROS) under high salt conditions, which can cause DNA damage and potentially lead to mutations. Moreover, our results showed that high salt condition alters the bacterium's lipopolysaccharide (LPS) synthesis, leading to a reduced expression of SodB in a Fur-dependent manner. This reduction, in turn, elevates ROS levels, culminating in a higher frequency of drug-resistance mutations. Our research underscores the critical need to consider environmental influences, such as diet and lifestyle, in managing bacterial infections and combating the growing challenge of antibiotic resistance.

8.
Int J Obes (Lond) ; 48(5): 646-653, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38297032

RESUMEN

BACKGROUND: We aim to assess the associations between the change in neighborhood socioeconomic score (SES) between birth and 6 years and childhood weight status and body composition from 6 to 13 years. METHODS: Data for 3909 children from the Generation R Study, a prospective population-based cohort in the Netherlands were analyzed. The change in neighborhood SES between birth and 6 years was defined as static-high, static-middle, static-low, upward, and downward mobility. Child body mass index (BMI), overweight and obesity (OWOB), fat mass index (FMI) and lean mass index (LMI) were measured at age 6, 10, and 13 years. The associations were explored using generalized estimating equations. The effect modification by child sex was examined. RESULTS: In total, 19.5% and 18.1% of children were allocated to the upward mobility and downward mobility neighborhood SES group. The associations between the change in neighborhood SES and child weight status and body composition were moderated by child sex (p < 0.05). Compared to girls in the static-high group, girls in the static-low group had relatively higher BMI-SDS (ß, 95% confidence interval (CI): 0.24, 0.09-0.40) and higher risk of OWOB (RR, 95% CI: 1.98, 1.35-2.91), together with higher FMI-SDS (ß, 95% CI: 0.27, 0.14-0.41) and LMI-SDS (ß, 95% CI: 0.18, 0.03-0.33). The associations in boys were not significant. CONCLUSIONS: An increased BMI and fat mass, and higher risk of OWOB from 6 to 13 years were evident in girls living in a low-SES neighborhood or moving downward from a high- to a low-SES neighborhood. Support for children and families from low-SES neighborhoods is warranted.


Asunto(s)
Composición Corporal , Obesidad Infantil , Clase Social , Humanos , Femenino , Masculino , Niño , Composición Corporal/fisiología , Adolescente , Países Bajos/epidemiología , Obesidad Infantil/epidemiología , Estudios Prospectivos , Preescolar , Índice de Masa Corporal , Características de la Residencia/estadística & datos numéricos , Lactante , Recién Nacido , Características del Vecindario/estadística & datos numéricos , Peso Corporal/fisiología
9.
Hepatology ; 2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38016019

RESUMEN

BACKGROUND AND AIMS: Base editing has shown great potential for treating human diseases with mutated genes. However, its potential for treating HCC has not yet been explored. APPROACH AND RESULTS: We employed adenine base editors (ABEs) to correct a telomerase reverse transcriptase ( TERT ) promoter mutation, which frequently occurs in various human cancers, including HCC. The mutated TERT promoter -124 C>T is corrected to -124 C by a single guide (sg) RNA-guided and deactivated Campylobacter jejuni Cas9 (CjCas9)-fused adenine base editor (CjABE). This edit impairs the binding of the E-twenty six/ternary complex factor transcription factor family, including E-twenty six-1 and GABPA, to the TERT promoter, leading to suppressed TERT promoter and telomerase activity, decreased TERT expression and cell proliferation, and increased cell senescence. Importantly, injection of adeno-associated viruses expressing sgRNA-guided CjABE or employment of lipid nanoparticle-mediated delivery of CjABE mRNA and sgRNA inhibits the growth of liver tumors harboring TERT promoter mutations. CONCLUSIONS: These findings demonstrate that a sgRNA-guided CjABE efficiently converts the mutated TERT promoter -124 C>T to -124 C in HCC cells and underscore the potential to treat HCC by the base editing-mediated correction of TERT promoter mutations.

10.
Nephrol Dial Transplant ; 39(8): 1333-1343, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-38244232

RESUMEN

BACKGROUND: Perturbation of gut microbiota has been linked to chronic kidney disease (CKD), which was correlated with a sophisticated milieu of metabolic and immune dysregulation. METHODS: To clarify the underlying host-microbe interaction in CKD, we performed multi-omics measurements, including systems-level gut microbiome, targeted serum metabolome and deep immunotyping, in a cohort of patients and non-CKD controls. RESULTS: Our analyses on functional profiles of the gut microbiome showed a decrease in the diversity and abundance of carbohydrate-active enzyme (CAZyme) genes but an increase in the abundance of antibiotic resistance, nitrogen cycling enzyme and virulence factor genes in CKD. Moreover, models generated using measurements of serum metabolites (amino acids, bile acids and short-chain fatty acids) or immunotypes were predictive of renal impairment but less so than many of the functional profiles derived from gut microbiota, with the CAZyme genes being the top-performing model to accurately predict the early stage of diseases. In addition, co-occurrence analyses revealed coordinated host-microbe relationships in CKD. Specifically, the highest fractions of significant correlations were identified with circulating metabolites by several taxonomic and functional profiles of gut microbiome, while immunotype features were moderately associated with the abundance of microbiome-encoded metabolic pathways and serum levels of amino acids (e.g. B cell cluster tryptophan and B cell cluster tryptophan metabolism). CONCLUSION: Overall, our multi-omics integration revealed several signatures of systems-level gut microbiome in robust associations with host-microbe co-metabolites and renal function, which may have aetiological and diagnostic implications in CKD.


Asunto(s)
Microbioma Gastrointestinal , Metagenómica , Insuficiencia Renal Crónica , Humanos , Insuficiencia Renal Crónica/microbiología , Insuficiencia Renal Crónica/inmunología , Masculino , Femenino , Persona de Mediana Edad , Metagenómica/métodos , Estudios de Casos y Controles , Anciano , Metaboloma
11.
Genomics ; 115(3): 110624, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37062365

RESUMEN

Leptospirosis can cause chronic kidney damage, putting patients at risk of additional kidney injury due to other factors that can lead to renal failure. To understand the combined effect, the transcriptome profiles of kidneys of mice with adenine-induced and chronically Leptospira-infected kidneys were analysed. Chronic inflammation and T-helper 17 immune responses were activated and a high-level expression of Indoleamine 2,3-dioxygenase 1 protein was found. The results indicate that the combination may predispose patients to chronic inflammation, kidney function disruption, and symptoms seen in progressive chronic kidney disease (CKD). Furthermore, immunometabolic regulation may contribute to renal injury caused by chronic leptospirosis with secondary nephrotoxic injury. This study identified several significantly disrupted genes that could serve as potential targets for the diagnosis or treatment of CKD. Our work provides insight into the combined effect of leptospirosis and secondary kidney damage and the molecular basis for rapid progression of CKD.


Asunto(s)
Antiinfecciosos , Leptospirosis , Insuficiencia Renal Crónica , Animales , Ratones , Transcriptoma , Leptospirosis/complicaciones , Riñón , Insuficiencia Renal Crónica/complicaciones , Inflamación
12.
Sensors (Basel) ; 24(17)2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39275446

RESUMEN

Particle plasmon resonance (PPR), or localized surface plasmon resonance (LSPR), utilizes intrinsic resonance in metal nanoparticles for sensor fabrication. While diffraction grating waveguides monitor bioaffinity adsorption with out-of-plane illumination, integrating them with PPR for biomolecular detection schemes remains underexplored. This study introduces a label-free biosensing platform integrating PPR with a diffraction grating waveguide. Gold nanoparticles are immobilized on a glass slide in contact with a sample, while a UV-assisted embossed diffraction grating is positioned opposite. The setup utilizes diffraction in reflection to detect changes in the environment's refractive index, indicating biomolecular binding at the gold nanoparticle surface. The positional shift of the diffracted beam, measured with varying refractive indices of sucrose solutions, shows a sensitivity of 0.97 mm/RIU at 8 cm from a position-sensitive detector, highlighting enhanced sensitivity due to PPR-diffraction coupling near the gold nanoparticle surface. Furthermore, the sensor achieved a resolution of 3.1 × 10-4 refractive index unit and a detection limit of 4.4 pM for detection of anti-DNP. The sensitivity of the diffracted spot was confirmed using finite element method (FEM) simulations in COMSOL Multiphysics. This study presents a significant advancement in biosensing technology, offering practical solutions for sensitive, rapid, and label-free biomolecule detection.


Asunto(s)
Técnicas Biosensibles , Oro , Nanopartículas del Metal , Resonancia por Plasmón de Superficie , Resonancia por Plasmón de Superficie/métodos , Oro/química , Nanopartículas del Metal/química , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Refractometría , Análisis de Elementos Finitos , Límite de Detección
13.
J Allergy Clin Immunol ; 151(4): 1123-1131, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36586539

RESUMEN

BACKGROUND: A dysregulated immune response is a hallmark of autoimmune disorders. Evidence suggests that systemic autoimmune diseases and primary immunodeficiency disorders (PIDs) may be similar diseases with different clinical phenotypes. OBJECTIVE: This study aimed to investigate the burden of PID-associated genetic variants in patients with childhood-onset systemic lupus erythematosus (cSLE). METHODS: We enrolled 118 cSLE patients regularly followed at Chang Gung Memorial Hospital. Targeted next-generation sequencing identified PID genetic variants in patients versus 1475 unrelated healthy individuals, which were further filtered by allelic frequency and various functional scores. Customized immune assays tested the functions of the identified variants. RESULTS: On filtration, 36 patients (30.5%) harbored rare variants in PID-associated genes predicted to be damaging. One homozygous TREX1 (c.294dupA) mutation and 4 heterozygous variants with possible dominant PID traits, including BCL11B (c.G1040T), NFKB1 (c.T695G), and NFKB2 (c.G1210A, c.G1651A), were discovered. With recessive traits, variants were found across all PID types; one fifth involved phagocyte number or function defects. Predicted pathogenic PID variants were more predominant in those with a family history of lupus, regardless of infection susceptibility. Moreover, mutation loads were greater among cSLE patients than controls despite sex or age at disease onset. While greater mutation loads were observed among cSLE patients with peripubertal disease onset, no significant differences in sex or phenotype were noted among cSLE patients. CONCLUSION: cSLE is mostly not monogenic. Gene-specific analysis and mutation load investigations suggested that rare and predicted damaging variants in PID-related genes can potentially contribute to cSLE susceptibility.


Asunto(s)
Enfermedades Autoinmunes , Lupus Eritematoso Sistémico , Niño , Humanos , Edad de Inicio , Lupus Eritematoso Sistémico/genética , Mutación , Fenotipo , Proteínas Represoras , Proteínas Supresoras de Tumor
14.
Infection ; 51(4): 967-980, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36512270

RESUMEN

PURPOSE: BK Polyomavirus (BKPyV) infection manifests as renal inflammation and can cause kidney damage. Tumor necrosis factor-α (TNF-α) is increased in renal inflammation and injury. The aim of this study was to investigate the effect of TNF-α blockade on BKPyV infection. METHODS: Urine specimens from 22 patients with BKPyV-associated nephropathy (BKPyVN) and 35 non-BKPyVN kidney transplant recipients were analyzed. RESULTS: We demonstrated increased urinary levels of TNF-α and its receptors, TNFR1 and TNFR2, in BKPyVN patients. Treating BKPyV-infected human proximal tubular cells (HRPTECs) with TNF-α stimulated the expression of large T antigen and viral capsid protein-1 mRNA and proteins and BKPyV promoter activity. Knockdown of TNFR1 or TNFR2 expression caused a reduction in TNF-α-stimulated viral replication. NF-κB activation induced by overexpression of constitutively active IKK2 significantly increased viral replication and the activity of the BKPyV promoter containing an NF-κB binding site. The addition of a NF-κB inhibitor on BKPyV-infected cells suppressed viral replication. Blockade of TNF-α functionality by etanercept reduced BKPyV-stimulated expression of TNF-α, interleukin-1ß (IL-1ß), IL-6 and IL-8 and suppressed TNF-α-stimulated viral replication. In cultured HRPTECs and THP-1 cells, BKPyV infection led to increased expression of TNF-α, interleukin-1 ß (IL-1ß), IL-6 and TNFR1 and TNFR2 but the stimulated magnitude was far less than that induced by poly(I:C). This may suggest that BKPyV-mediated autocrine effect is not a major source of TNFα. CONCLUSION: TNF-α stimulates BKPyV replication and inhibition of its signal cascade or functionality attenuates its stimulatory effect. Our study provides a therapeutic anti-BKPyV target.


Asunto(s)
Virus BK , Infecciones por Polyomavirus , Humanos , Virus BK/genética , Factor de Necrosis Tumoral alfa , Receptores Tipo I de Factores de Necrosis Tumoral , Receptores Tipo II del Factor de Necrosis Tumoral/genética , FN-kappa B , Interleucina-6 , Infecciones por Polyomavirus/metabolismo , Infecciones por Polyomavirus/patología , Inflamación
15.
Circulation ; 144(22): 1760-1776, 2021 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-34698513

RESUMEN

BACKGROUND: Loss of dystrophin protein causes Duchenne muscular dystrophy (DMD), characterized by progressive degeneration of cardiac and skeletal muscles, and mortality in adolescence or young adulthood. Although cardiac failure has risen as the leading cause of mortality in patients with DMD, effective therapeutic interventions remain underdeveloped, in part, because of the lack of a suitable preclinical model. METHODS: We analyzed a novel murine model of DMD created by introducing a 4-bp deletion into exon 4, one of the exons encoding the actin-binding domain 1 of dystrophin (referred to as DmdE4* mice). Echocardiography, microcomputed tomography, muscle force measurement, and histological analysis were performed to determine cardiac and skeletal muscle defects in these mice. Using this model, we examined the feasibility of using a cytidine base editor to install exon skipping and rescue dystrophic cardiomyopathy in vivo. AAV9-based CRISPR/Cas9-AID (eTAM) together with AAV9-sgRNA was injected into neonatal DmdE4* mice, which were analyzed 2 or 12 months after treatment to evaluate the extent of exon skipping, dystrophin restoration, and phenotypic improvements of cardiac and skeletal muscles. RESULTS: DmdE4* mice recapitulated many aspects of human DMD, including shortened life span (by ≈50%), progressive cardiomyopathy, kyphosis, profound loss of muscle strength, and myocyte degeneration. A single-dose administration of AAV9-eTAM instituted >50% targeted exon skipping in the Dmd transcripts and restored up to 90% dystrophin in the heart. As a result, early ventricular remodeling was prevented and cardiac and skeletal muscle functions were improved, leading to an increased life span of the DmdE4* mice. Despite gradual decline of AAV vector and base editor expression, dystrophin restoration and pathophysiological rescue of muscular dystrophy were long lasted for at least 1 year. CONCLUSIONS: Our study demonstrates the feasibility and efficacy to institute exon skipping through an enhanced TAM (eTAM) for therapeutic application(s).


Asunto(s)
Desaminasas APOBEC , Sistemas CRISPR-Cas , Cardiomiopatías , Distrofina , Exones , Distrofia Muscular de Duchenne , Desaminasas APOBEC/biosíntesis , Desaminasas APOBEC/genética , Animales , Cardiomiopatías/genética , Cardiomiopatías/metabolismo , Dependovirus , Distrofina/biosíntesis , Distrofina/genética , Vectores Genéticos , Humanos , Ratones , Ratones Endogámicos mdx , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/terapia
16.
Gastroenterology ; 161(1): 301-317.e16, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33819485

RESUMEN

BACKGROUND & AIMS: Limited understanding of pruritus mechanisms in cholestatic liver diseases hinders development of antipruritic treatments. Previous studies implicated lysophosphatidic acid (LPA) as a potential mediator of cholestatic pruritus. METHODS: Pruritogenicity of lysophosphatidylcholine (LPC), LPA's precursor, was examined in naïve mice, cholestatic mice, and nonhuman primates. LPC's pruritogenicity involving keratinocyte TRPV4 was studied using genetic and pharmacologic approaches, cultured keratinocytes, ion channel physiology, and structural computational modeling. Activation of pruriceptor sensory neurons by microRNA-146a (miR-146a), secreted from keratinocytes, was identified by in vitro and ex vivo Ca2+ imaging assays. Sera from patients with primary biliary cholangitis were used for measuring the levels of LPC and miR-146a. RESULTS: LPC was robustly pruritic in mice. TRPV4 in skin keratinocytes was essential for LPC-induced itch and itch in mice with cholestasis. Three-dimensional structural modeling, site-directed mutagenesis, and channel function analysis suggested a TRPV4 C-terminal motif for LPC binding and channel activation. In keratinocytes, TRPV4 activation by LPC induced extracellular release of miR-146a, which activated TRPV1+ sensory neurons to cause itch. LPC and miR-146a levels were both elevated in sera of patients with primary biliary cholangitis with itch and correlated with itch intensity. Moreover, LPC and miR-146a were also increased in sera of cholestatic mice and elicited itch in nonhuman primates. CONCLUSIONS: We identified LPC as a novel cholestatic pruritogen that induces itch through epithelia-sensory neuron cross talk, whereby it directly activates skin keratinocyte TRPV4, which rapidly releases miR-146a to activate skin-innervating TRPV1+ pruriceptor sensory neurons. Our findings support the new concept of the skin, as a sensory organ, playing a critical role in cholestatic itch, beyond liver, peripheral sensory neurons, and central neural pathways supporting pruriception.


Asunto(s)
Colestasis/complicaciones , Queratinocitos/metabolismo , Lisofosfatidilcolinas , Prurito/metabolismo , Células Receptoras Sensoriales/metabolismo , Piel/inervación , Canales Catiónicos TRPV/metabolismo , Adulto , Anciano , Animales , Conducta Animal , Células Cultivadas , Colestasis/genética , Colestasis/metabolismo , Colestasis/fisiopatología , Modelos Animales de Enfermedad , Femenino , Humanos , Macaca mulatta , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Prurito/inducido químicamente , Prurito/genética , Prurito/fisiopatología , Transducción de Señal , Canales Catiónicos TRPV/genética
17.
Int J Obes (Lond) ; 46(9): 1703-1711, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35821522

RESUMEN

BACKGROUND/OBJECTIVES: This study analysed the relationship between early childhood socioeconomic status (SES) measured by maternal education and household income and the subsequent development of childhood overweight and obesity. SUBJECTS/METHODS: Data from seven population-representative prospective child cohorts in six high-income countries: United Kingdom, Australia, the Netherlands, Canada (one national cohort and one from the province of Quebec), USA, Sweden. Children were included at birth or within the first 2 years of life. Pooled estimates relate to a total of N = 26,565 included children. Overweight and obesity were defined using International Obesity Task Force (IOTF) cut-offs and measured in late childhood (8-11 years). Risk ratios (RRs) and pooled risk estimates were adjusted for potential confounders (maternal age, ethnicity, child sex). Slope Indexes of Inequality (SII) were estimated to quantify absolute inequality for maternal education and household income. RESULTS: Prevalence ranged from 15.0% overweight and 2.4% obese in the Swedish cohort to 37.6% overweight and 15.8% obese in the US cohort. Overall, across cohorts, social gradients were observed for risk of obesity for both low maternal education (pooled RR: 2.99, 95% CI: 2.07, 4.31) and low household income (pooled RR: 2.69, 95% CI: 1.68, 4.30); between-cohort heterogeneity ranged from negligible to moderate (p: 0.300 to < 0.001). The association between RRs of obesity by income was lowest in Sweden than in other cohorts. CONCLUSIONS: There was a social gradient by maternal education on the risk of childhood obesity in all included cohorts. The SES associations measured by income were more heterogeneous and differed between Sweden versus the other national cohorts; these findings may be attributable to policy differences, including preschool policies, maternity leave, a ban on advertising to children, and universal free school meals.


Asunto(s)
Sobrepeso , Obesidad Infantil , Cohorte de Nacimiento , Índice de Masa Corporal , Niño , Preescolar , Países Desarrollados , Femenino , Humanos , Renta , Recién Nacido , Sobrepeso/epidemiología , Obesidad Infantil/epidemiología , Embarazo , Prevalencia , Estudios Prospectivos , Factores de Riesgo
18.
Immunity ; 39(2): 272-85, 2013 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-23973223

RESUMEN

Regulatory T (Treg) cells suppress inflammatory immune responses and autoimmunity caused by self-reactive T cells. The key Treg cell transcription factor Foxp3 is downregulated during inflammation to allow for the acquisition of effector T cell-like functions. Here, we demonstrate that stress signals elicited by proinflammatory cytokines and lipopolysaccharides lead to the degradation of Foxp3 through the action of the E3 ubiquitin ligase Stub1. Stub1 interacted with Foxp3 to promote its K48-linked polyubiquitination in an Hsp70-dependent manner. Knockdown of endogenous Stub1 or Hsp70 prevented Foxp3 degradation. Furthermore, the overexpression of Stub1 in Treg cells abrogated their ability to suppress inflammatory immune responses in vitro and in vivo and conferred a T-helper-1-cell-like phenotype. Our results demonstrate the critical role of the stress-activated Stub1-Hsp70 complex in promoting Treg cell inactivation, thus providing a potential therapeutic target for the intervention against autoimmune disease, infection, and cancer.


Asunto(s)
Factores de Transcripción Forkhead/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/metabolismo , Células Cultivadas , Citocinas/metabolismo , Inhibidores Enzimáticos , Células HEK293 , Proteínas HSP70 de Choque Térmico/genética , Humanos , Imidazoles , Inflamación/genética , Inflamación/inmunología , Lipopolisacáridos/metabolismo , Ratones , Ratones Endogámicos BALB C , Fenotipo , Piridinas , Interferencia de ARN , ARN Interferente Pequeño , Linfocitos T Colaboradores-Inductores/inmunología , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación
19.
Circ Res ; 127(7): e148-e165, 2020 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-32693673

RESUMEN

RATIONALE: Impaired autophagic flux contributes to ischemia/reperfusion (I/R)-induced cardiomyocyte death, but the underlying molecular mechanisms remain largely unexplored. OBJECTIVE: To determine the role of LAPTM4B (lysosomal-associated transmembrane protein 4B) in the regulation of autophagic flux and myocardial I/R injury. METHODS AND RESULTS: LAPTM4B was expressed in murine hearts but downregulated in hearts with I/R (30 minutes/2 hours) injury and neonatal rat cardiomyocytes with hypoxia/reoxygenation (6 hours/2 hours) injury. During myocardial reperfusion, LAPTM4B-knockout (LAPTM4B-/-) mice had a significantly increased infarct size and lactate dehydrogenase release, whereas adenovirus-mediated LAPTM4B-overexpression was cardioprotective. Concomitantly, LAPTM4B-/- mice showed higher accumulation of the autophagy markers LC3-II (microtubule-associated protein 1A/1B-light chain 3), but not P62, in the I/R heart, whereas they did not alter chloroquine-induced further increases of LC3-II and P62 in both sham and I/R hearts. Conversely, LAPTM4B-overexpression had opposite effects. The hypoxia/reoxygenation-reduced viability of neonatal rat cardiomyocytes, ratio of autolysosomes/autophagosomes, and function of lysosomes were further decreased by LAPTM4B-knockdown but reversed by LAPTM4B-overexpression. Moreover, the LAPTM4B-overexpression-mediated benefits were abolished by knockdown of lysosome-associated membrane protein-2 (an autophagosome-lysosome fusion protein) in vivo and by the autophagy inhibitor bafilomycin A1 in vivo. In contrast, rapamycin (Rapa) successfully restored the impaired autophagic flux in LAPTM4B-/- mice and the subsequent myocardial I/R injury. Mechanistically, LAPTM4B regulated the activity of mTORC1 (mammalian target of rapamycin complex 1) via interacting with mTOR through its EC3 (extracelluar) domain. Thus, mTORC1 was overactivated in LAPTM4B-/- mice, leading to the repression of TFEB (transcription factor EB), a master regulator of lysosomal and autophagic genes, during myocardial I/R. The mTORC1 inhibition or TFEB-overexpression rescued the LAPTM4B-/--induced impairment in autophagic flux and I/R injury, whereas TFEB-knockdown abolished the LAPTM4B-overexpression-mediated recovery of autophagic flux and cardioprotection. CONCLUSIONS: The downregulation of LAPTM4B contributes to myocardial I/R-induced impairment of autophagic flux via modulation of the mTORC1/TFEB pathway. Graphic Abstract: A graphic abstract is available for this article.


Asunto(s)
Autofagosomas/metabolismo , Autofagia , Lisosomas/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Infarto del Miocardio/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Miocitos Cardíacos/metabolismo , Animales , Autofagosomas/genética , Autofagosomas/patología , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Células Cultivadas , Modelos Animales de Enfermedad , Regulación hacia Abajo , Lisosomas/genética , Lisosomas/patología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Asociadas a Microtúbulos , Infarto del Miocardio/genética , Infarto del Miocardio/patología , Infarto del Miocardio/prevención & control , Daño por Reperfusión Miocárdica/genética , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/prevención & control , Miocitos Cardíacos/patología , Ratas Sprague-Dawley , Proteína Sequestosoma-1/metabolismo , Transducción de Señal
20.
Nephrol Dial Transplant ; 37(10): 1982-1992, 2022 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-34612498

RESUMEN

BACKGROUND: Restless legs syndrome (RLS) is common among patients with end-stage kidney disease (ESKD) and is associated with poor outcomes. Several recently published studies had focused on pharmacological and non-pharmacological treatments of RLS, but an updated meta-analysis has not been conducted. METHODS: The study population was adult ESKD patients on dialysis with RLS. Randomized controlled trials (RCTs) were selected. The primary outcome was reduction in RLS severity. The secondary outcomes were improvement in sleep quality and treatment-related adverse events. Frequentist standard network meta-analysis (NMA) and additive component NMA were performed. The evidence certainty was assessed using the Confidence in NMA (CINeMA) framework. RESULTS: A total of 24 RCTs with 1252 participants were enrolled and 14 interventions were compared. Cool dialysate produced the largest RLS severity score reduction {mean difference [MD] 16.82 [95% confidence interval (CI) 10.635-23.02]} and a high level of confidence. Other potential non-pharmacological interventions include intradialytic stretching exercise [MD 12.00 (95% CI 7.04-16.97)] and aromatherapy massage [MD 10.91 (95% CI 6.96-14.85)], but all with limited confidence of evidence. Among the pharmacological interventions, gabapentin was the most effective [MD 8.95 (95% CI 1.95-15.85)], which also improved sleep quality [standardized MD 2.00 (95% CI 0.47-3.53)]. No statically significant adverse events were detected. CONCLUSIONS: The NMA supports that cool dialysate is appropriate to treat patients with ESKD and RLS. Gabapentin is the most effective pharmacological intervention and also might improve sleep quality. Further parallel RCTs with sufficient sample sizes are required to evaluate these potential interventions and long-term effects.


Asunto(s)
Fallo Renal Crónico , Síndrome de las Piernas Inquietas , Adulto , Soluciones para Diálisis , Gabapentina/uso terapéutico , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Metaanálisis en Red , Diálisis Renal/efectos adversos , Síndrome de las Piernas Inquietas/tratamiento farmacológico , Síndrome de las Piernas Inquietas/terapia
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