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1.
Nat Chem Biol ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538923

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-38166470

RESUMO

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.


Assuntos
Miocárdio , Retículo Sarcoplasmático , Animais , Camundongos , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Mamíferos , Camundongos Knockout , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
3.
Cell ; 146(5): 772-84, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21871655

RESUMO

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.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Linfócitos T Reguladores/citologia , Células Th17/citologia , Animais , Sequência de Bases , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Humanos , Fator 1 Induzível por Hipóxia/metabolismo , Interleucina-17/genética , Interleucina-17/imunologia , Células Jurkat , Camundongos , Dados de Sequência Molecular , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fator de Transcrição STAT3/metabolismo , Alinhamento de Sequência , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo
4.
Immunity ; 45(1): 83-93, 2016 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-27438767

RESUMO

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.


Assuntos
Proteínas de Transporte/metabolismo , Colite/imunologia , Interleucina-6/metabolismo , MicroRNAs/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Linfócitos T Reguladores/imunologia , Animais , Proteínas de Transporte/genética , Células Cultivadas , Proteínas de Ligação a DNA , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/metabolismo , Humanos , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Interleucina-6/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , Proteínas do Tecido Nervoso/genética , Tolerância a Antígenos Próprios
5.
Kidney Int ; 105(3): 442-444, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38388145

RESUMO

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.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Hipoglicemiantes/efeitos adversos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Receptor do Peptídeo Semelhante ao Glucagon 1
6.
Hum Mol Genet ; 31(10): 1560-1573, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-34957500

RESUMO

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.


Assuntos
Cistos , Metformina , Rim Policístico Autossômico Dominante , Animais , Cistos/metabolismo , Modelos Animais de Doenças , Feminino , Rim/metabolismo , Ácido Láctico/metabolismo , Masculino , Metformina/metabolismo , Metformina/farmacologia , Camundongos , Camundongos Transgênicos , Doenças Renais Policísticas , Rim Policístico Autossômico Dominante/tratamento farmacológico , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Dominante/metabolismo , Canais de Cátion TRPP/genética , Canais de Cátion TRPP/metabolismo
7.
Int J Obes (Lond) ; 48(5): 646-653, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38297032

RESUMO

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.


Assuntos
Composição Corporal , Obesidade Infantil , Classe Social , Humanos , Feminino , Masculino , Criança , Composição Corporal/fisiologia , Adolescente , Países Baixos/epidemiologia , Obesidade Infantil/epidemiologia , Estudos Prospectivos , Pré-Escolar , Índice de Massa Corporal , Características de Residência/estatística & dados numéricos , Lactente , Recém-Nascido , Características da Vizinhança/estatística & dados numéricos , Peso Corporal/fisiologia
8.
Hepatology ; 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38016019

RESUMO

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.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38244232

RESUMO

BACKGROUND AND HYPOTHESIS: 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 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 functional profiles derived from gut microbiota, with the CAZyme genes being the top performing model to accurately predict 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 be of etiological and diagnostic implications in CKD.

10.
Genomics ; 115(3): 110624, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37062365

RESUMO

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.


Assuntos
Anti-Infecciosos , Leptospirose , Insuficiência Renal Crônica , Animais , Camundongos , Transcriptoma , Leptospirose/complicações , Rim , Insuficiência Renal Crônica/complicações , Inflamação
11.
J Allergy Clin Immunol ; 151(4): 1123-1131, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36586539

RESUMO

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.


Assuntos
Doenças Autoimunes , Lúpus Eritematoso Sistêmico , Criança , Humanos , Idade de Início , Lúpus Eritematoso Sistêmico/genética , Mutação , Fenótipo , Proteínas Repressoras , Proteínas Supressoras de Tumor
12.
Infection ; 51(4): 967-980, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36512270

RESUMO

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.


Assuntos
Vírus BK , Infecções por Polyomavirus , Humanos , Vírus BK/genética , Fator de Necrose Tumoral alfa , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral/genética , NF-kappa B , Interleucina-6 , Infecções por Polyomavirus/metabolismo , Infecções por Polyomavirus/patologia , Inflamação
13.
Circulation ; 144(22): 1760-1776, 2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34698513

RESUMO

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).


Assuntos
Desaminases APOBEC , Sistemas CRISPR-Cas , Cardiomiopatias , Distrofina , Éxons , Distrofia Muscular de Duchenne , Desaminases APOBEC/biossíntese , Desaminases APOBEC/genética , Animais , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Dependovirus , Distrofina/biossíntese , Distrofina/genética , Vetores Genéticos , Humanos , Camundongos , Camundongos Endogâmicos mdx , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/terapia
14.
Gastroenterology ; 161(1): 301-317.e16, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33819485

RESUMO

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.


Assuntos
Colestase/complicações , Queratinócitos/metabolismo , Lisofosfatidilcolinas , Prurido/metabolismo , Células Receptoras Sensoriais/metabolismo , Pele/inervação , Canais de Cátion TRPV/metabolismo , Adulto , Idoso , Animais , Comportamento Animal , Células Cultivadas , Colestase/genética , Colestase/metabolismo , Colestase/fisiopatologia , Modelos Animais de Doenças , Feminino , Humanos , Macaca mulatta , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Prurido/induzido quimicamente , Prurido/genética , Prurido/fisiopatologia , Transdução de Sinais , Canais de Cátion TRPV/genética
15.
Int J Obes (Lond) ; 46(9): 1703-1711, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35821522

RESUMO

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.


Assuntos
Sobrepeso , Obesidade Infantil , Coorte de Nascimento , Índice de Massa Corporal , Criança , Pré-Escolar , Países Desenvolvidos , Feminino , Humanos , Renda , Recém-Nascido , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Gravidez , Prevalência , Estudos Prospectivos , Fatores de Risco
16.
Immunity ; 39(2): 272-85, 2013 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-23973223

RESUMO

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.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Células Cultivadas , Citocinas/metabolismo , Inibidores Enzimáticos , Células HEK293 , Proteínas de Choque Térmico HSP70/genética , Humanos , Imidazóis , Inflamação/genética , Inflamação/imunologia , Lipopolissacarídeos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Fenótipo , Piridinas , Interferência de RNA , RNA Interferente Pequeno , Linfócitos T Auxiliares-Indutores/imunologia , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
17.
Circ Res ; 127(7): e148-e165, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32693673

RESUMO

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.


Assuntos
Autofagossomos/metabolismo , Autofagia , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Autofagossomos/genética , Autofagossomos/patologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Regulação para Baixo , Lisossomos/genética , Lisossomos/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/patologia , Ratos Sprague-Dawley , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais
18.
Nephrol Dial Transplant ; 37(10): 1982-1992, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34612498

RESUMO

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.


Assuntos
Falência Renal Crônica , Síndrome das Pernas Inquietas , Adulto , Soluções para Diálise , Gabapentina/uso terapêutico , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Metanálise em Rede , Diálise Renal/efeitos adversos , Síndrome das Pernas Inquietas/tratamento farmacológico , Síndrome das Pernas Inquietas/terapia
19.
Acta Pharmacol Sin ; 43(3): 588-601, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33967278

RESUMO

Cardiac hypertrophy is a common adaptive response to a variety of stimuli, but prolonged hypertrophy leads to heart failure. Hence, discovery of agents treating cardiac hypertrophy is urgently needed. In the present study, we investigated the effects of QF84139, a newly synthesized pyrazine derivative, on cardiac hypertrophy and the underlying mechanisms. In neonatal rat cardiomyocytes (NRCMs), pretreatment with QF84139 (1-10 µM) concentration-dependently inhibited phenylephrine-induced hypertrophic responses characterized by fetal genes reactivation, increased ANP protein level and enlarged cardiomyocytes. In adult male mice, administration of QF84139 (5-90 mg·kg-1·d-1, i.p., for 2 weeks) dose-dependently reversed transverse aortic constriction (TAC)-induced cardiac hypertrophy displayed by cardiomyocyte size, left ventricular mass, heart weights, and reactivation of fetal genes. We further revealed that QF84139 selectively activated the AMPK signaling pathway without affecting the phosphorylation of CaMKIIδ, ERK1/2, AKT, PKCε, and P38 kinases in phenylephrine-treated NRCMs and in the hearts of TAC-treated mice. In NRCMs, QF84139 did not show additive effects with metformin on the AMPK activation, whereas the anti-hypertrophic effect of QF84139 was abolished by an AMPK inhibitor Compound C or knockdown of AMPKα2. In AMPKα2-deficient mice, the anti-hypertrophic effect of QF84139 was also vanished. These results demonstrate that QF84139 attenuates the PE- and TAC-induced cardiac hypertrophy via activating the AMPK signaling. This structurally novel compound would be a promising lead compound for developing effective agents for the treatment of cardiac hypertrophy.


Assuntos
Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Cardiomegalia/patologia , Miócitos Cardíacos/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Aorta/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tamanho do Órgão/efeitos dos fármacos , Fenilefrina/farmacologia , RNA Interferente Pequeno/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
20.
BMC Geriatr ; 22(1): 841, 2022 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-36344918

RESUMO

BACKGROUND: Polypharmacy can be defined as using five or more medications simultaneously. "Medication-related problems", an extension of polypharmacy, includes inappropriate prescribing, poor adherence, overdosage, underdosage, inappropriate drug selection, inadequate monitoring, adverse drug effects, and drug interactions. Polypharmacy and the high risk of medication-related problems among older people are associated with adverse health consequences due to drug-drug interactions, drug-disease interactions, and adverse drug effects. This study aims to assess the factors associated with polypharmacy and the high risk of medication-related problems among community-dwelling older people in the Netherlands, Greece, Croatia, Spain, United Kingdom. METHOD: This longitudinal study used baseline and follow-up data from 1791 participants of the Urban Health Center European project. Polypharmacy and the risk of medication-related problems were evaluated at baseline and follow-up using the Medication Risk Questionnaire. We studied factors in the domains (a) sociodemographic characteristics, (b) lifestyle and nutrition, and (c) health and health care use. Hierarchical logistic regression analyses were used to examine the factors associated with polypharmacy and the high risk of medication-related problems. RESULTS: Mean age was 79.6 years (SD ± 5.6 years); 60.8% were women; 45.2% had polypharmacy, and 41.8% had a high risk of medication-related problems. Women participants had lower odds of polypharmacy (OR = 0.55;95%CI:0.42-0.72) and a high risk of medication-related problems (OR = 0.50; 95%CI:0.39-0.65). Participants with a migration background (OR = 1.67;95%CI:1.08-2.59), overweight (OR = 1.37; 95%CI:1.04-1.79) and obesity (OR = 1.78;95%CI:1.26-2.51) compared to 'normal weight', with lower physical HRQoL (OR = 0.96, 95%CI:0.95-0.98), multi-morbidity (OR = 3.73, 95%CI:2.18-6.37), frailty (OR = 1.69, 95%CI:1.24-2.30), visited outpatient services (OR = 1.77, 95%CI: 1.09-2.88) had higher odds of polypharmacy. The associations with the high risk of medication-related problems were similar. CONCLUSIONS: Multiple factors in demography, lifestyle, nutrition, and health care use are associated with polypharmacy and the high risk of medication-related problems. Polypharmacy is a single element that may reflect the number of medications taken. The broader content of medication-related problems should be considered to assess the context of medication use among older people comprehensively. These provide starting points to improve interventions to reduce polypharmacy and high risk of medication-related problems. In the meantime, health professionals can apply these insights to identify subgroups of patients at a high risk of polypharmacy and medication-related problems. TRIAL REGISTRATION: The intervention of the UHCE project was registered in the ISRCTN registry as ISRCTN52788952. The date of registration is 13/03/2017.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Polimedicação , Humanos , Feminino , Idoso , Masculino , Vida Independente , Estudos Longitudinais , Europa (Continente)/epidemiologia , Prescrição Inadequada , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia
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