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1.
Cell ; 152(1-2): 82-96, 2013 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-23313552

RESUMEN

The induction of pluripotency or trans-differentiation of one cell type to another can be accomplished with cell-lineage-specific transcription factors. Here, we report that repression of a single RNA binding polypyrimidine-tract-binding (PTB) protein, which occurs during normal brain development via the action of miR-124, is sufficient to induce trans-differentiation of fibroblasts into functional neurons. Besides its traditional role in regulated splicing, we show that PTB has a previously undocumented function in the regulation of microRNA functions, suppressing or enhancing microRNA targeting by competitive binding on target mRNA or altering local RNA secondary structure. A key event during neuronal induction is the relief of PTB-mediated blockage of microRNA action on multiple components of the REST complex, thereby derepressing a large array of neuronal genes, including miR-124 and multiple neuronal-specific transcription factors, in nonneuronal cells. This converts a negative feedback loop to a positive one to elicit cellular reprogramming to the neuronal lineage.


Asunto(s)
Diferenciación Celular , Fibroblastos/citología , MicroARNs/genética , Neuronas/citología , Proteína de Unión al Tracto de Polipirimidina/metabolismo , Animales , Línea Celular , Linaje de la Célula , Regulación hacia Abajo , Humanos , Ratones , MicroARNs/metabolismo , Proteína de Unión al Tracto de Polipirimidina/genética , Empalme del ARN , Sinapsis
2.
Cell ; 145(7): 1023-35, 2011 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-21703447

RESUMEN

Barrett's esophagus is an intestine-like metaplasia and precursor of esophageal adenocarcinoma. Triggered by gastroesophageal reflux disease, the origin of this metaplasia remains unknown. p63-deficient mice, which lack squamous epithelia, may model acid-reflux damage. We show here that p63 null embryos rapidly develop intestine-like metaplasia with gene expression profiles similar to Barrett's metaplasia. We track its source to a unique embryonic epithelium that is normally undermined and replaced by p63-expressing cells. Significantly, we show that a discrete population of these embryonic cells persists in adult mice and humans at the squamocolumnar junction, the source of Barrett's metaplasia. We show that upon programmed damage to the squamous epithelium, these embryonic cells migrate toward adjacent, specialized squamous cells in a process that may recapitulate early Barrett's. Our findings suggest that certain precancerous lesions, such as Barrett's, initiate not from genetic alterations but from competitive interactions between cell lineages driven by opportunity.


Asunto(s)
Esófago de Barrett/patología , Esófago/patología , Animales , Esófago de Barrett/embriología , Perfilación de la Expresión Génica , Humanos , Intestino Delgado/citología , Metaplasia , Ratones , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Transactivadores/genética , Transactivadores/metabolismo
3.
Am J Pathol ; 193(7): 883-898, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37146965

RESUMEN

Fungal keratitis remains a major cause of severe visual loss in developing countries because of limited choices of therapy. The progression of fungal keratitis is a race between the innate immune system and the outgrowth of fungal conidia. Programmed necrosis (necroptosis), a type of proinflammatory cell death, has been recognized as a critical pathologic change in several diseases. However, the role and potential regulatory mechanisms of necroptosis have not been investigated in corneal diseases. The current study showed, for the first time, that fungal infection triggered significant corneal epithelial necroptosis in human/mouse/in vitro models. Moreover, a reduction in excessive reactive oxygen species release effectively prevented necroptosis. NLRP3 knockout did not affect necroptosis in vivo. In contrast, ablation of necroptosis via RIPK3 knockout significantly delayed migration and inhibited the nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome in macrophages, which enhanced the progression of fungal keratitis. Taking these findings together, the study indicated that overproduction of reactive oxygen species in fungal keratitis leads to significant necroptosis in the corneal epithelium. Furthermore, the necroptotic stimuli-mediated NLRP3 inflammasome serves as a driving force in host defense against fungal infection.


Asunto(s)
Inflamasomas , Queratitis , Humanos , Animales , Ratones , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Necroptosis , Apoptosis/fisiología , Proteínas Quinasas/metabolismo , Estrés Oxidativo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo
4.
Exp Eye Res ; 242: 109862, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38490292

RESUMEN

The continual exposure of retinal tissues to oxidative stress leads to discernible anatomical and physiological alterations. Specifically, the onslaught of oxidative damage escalates the irreversible death of retinal pigmented epithelium (RPE) cells, pinpointed as the fundamental pathological event in dry age-related macular degeneration (AMD). There is a conspicuous lack of effective therapeutic strategies to counteract this degenerative process. This study screened a library of antioxidants for their ability to protect RPE cells against oxidative stress and identified L-ergothioneine (EGT) as a potent cytoprotective agent. L-ergothioneine provided efficient protection against oxidative stress-damaged RPE and maintained cell redox homeostasis and normal physiological functions. It maintained the normal structure of the retina in mice under oxidative stress conditions. Transcriptomic analysis revealed that EGT counteracted major gene expression changes induced by oxidative stress. It upregulated antioxidant gene expression and inhibited NRF2 translocation. The inhibition of NRF2 abolished EGT's protective effects, suggesting that NRF2 activation contributes to its mechanism of action. In conclusion, we identified EGT as a safe and effective small-molecule compound that is expected to be a novel antioxidative agent for treating AMD.


Asunto(s)
Antioxidantes , Ergotioneína , Factor 2 Relacionado con NF-E2 , Estrés Oxidativo , Epitelio Pigmentado de la Retina , Epitelio Pigmentado de la Retina/efectos de los fármacos , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/patología , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Animales , Ergotioneína/farmacología , Antioxidantes/farmacología , Estrés Oxidativo/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Degeneración Macular/tratamiento farmacológico , Degeneración Macular/metabolismo , Degeneración Macular/patología , Células Cultivadas , Humanos , Western Blotting , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
5.
Development ; 147(22)2020 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-33144400

RESUMEN

In terrestrial animals, the lacrimal drainage apparatus evolved to serve as conduits for tear flow; however, little is known about the ontogenesis of this system. Here, we define the anatomy of the fully formed tear duct in mice, characterize crucial morphogenetic events for the development of tear duct components and identify the site for primordial tear duct (PTD) initiation. We report that the PTD originates from the orbital lacrimal lamina, a junction formed by the epithelia of the maxillary and lateral nasal processes. We demonstrate that Prickle1, a key component of planar cell polarity signaling, is expressed in progenitors of the PTD and throughout tear duct morphogenesis. Disruption of Prickle1 stalls tear duct elongation; in particular, the loss of basement membrane deposition and aberrant cytoplasmic accumulation of laminin are salient. Altered cell adhesion, cytoskeletal transport systems, vesicular transport systems and cell axis orientation in Prickle1 mutants support the role of Prickle1 in planar cell polarity. Taken together, our results highlight a crucial role of Prickle1-mediated polarized basement membrane secretion and deposition in PTD elongation.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Membrana Basal/embriología , Polaridad Celular/fisiología , Proteínas con Dominio LIM/metabolismo , Conducto Nasolagrimal/embriología , Organogénesis/fisiología , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Membrana Basal/citología , Adhesión Celular/fisiología , Citoesqueleto/genética , Citoesqueleto/metabolismo , Proteínas con Dominio LIM/genética , Ratones , Conducto Nasolagrimal/citología
6.
Mol Cell ; 59(6): 931-40, 2015 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-26365380

RESUMEN

Glaucoma, a blinding neurodegenerative disease, whose risk factors include elevated intraocular pressure (IOP), age, and genetics, is characterized by accelerated and progressive retinal ganglion cell (RGC) death. Despite decades of research, the mechanism of RGC death in glaucoma is still unknown. Here, we demonstrate that the genetic effect of the SIX6 risk variant (rs33912345, His141Asn) is enhanced by another major POAG risk gene, p16INK4a (cyclin-dependent kinase inhibitor 2A, isoform INK4a). We further show that the upregulation of homozygous SIX6 risk alleles (CC) leads to an increase in p16INK4a expression, with subsequent cellular senescence, as evidenced in a mouse model of elevated IOP and in human POAG eyes. Our data indicate that SIX6 and/or IOP promotes POAG by directly increasing p16INK4a expression, leading to RGC senescence in adult human retinas. Our study provides important insights linking genetic susceptibility to the underlying mechanism of RGC death and provides a unified theory of glaucoma pathogenesis.


Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Glaucoma de Ángulo Abierto/metabolismo , Proteínas de Homeodominio/fisiología , Células Ganglionares de la Retina/fisiología , Transactivadores/fisiología , Secuencia de Aminoácidos , Animales , Estudios de Casos y Controles , Muerte Celular , Línea Celular , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Glaucoma de Ángulo Abierto/genética , Glaucoma de Ángulo Abierto/patología , Humanos , Ratones Endogámicos C57BL , Ratones Noqueados , Datos de Secuencia Molecular , Mutación Missense , Regulación hacia Arriba
7.
Proc Natl Acad Sci U S A ; 117(8): 4328-4336, 2020 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-32029582

RESUMEN

Epigenetic alterations and metabolic dysfunction are two hallmarks of aging. However, the mechanism of how their interaction regulates aging, particularly in mammals, remains largely unknown. Here we show ELOVL fatty acid elongase 2 (Elovl2), a gene whose epigenetic alterations are most highly correlated with age prediction, contributes to aging by regulating lipid metabolism. Impaired Elovl2 function disturbs lipid synthesis with increased endoplasmic reticulum stress and mitochondrial dysfunction, leading to key accelerated aging phenotypes. Restoration of mitochondrial activity can rescue age-related macular degeneration (AMD) phenotypes induced by Elovl2 deficiency in human retinal pigmental epithelial (RPE) cells. We revealed an epigenetic-metabolism axis contributing to aging and potentially to antiaging therapy.

8.
Nature ; 531(7594): 323-8, 2016 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-26958831

RESUMEN

The repair and regeneration of tissues using endogenous stem cells represents an ultimate goal in regenerative medicine. To our knowledge, human lens regeneration has not yet been demonstrated. Currently, the only treatment for cataracts, the leading cause of blindness worldwide, is to extract the cataractous lens and implant an artificial intraocular lens. However, this procedure poses notable risks of complications. Here we isolate lens epithelial stem/progenitor cells (LECs) in mammals and show that Pax6 and Bmi1 are required for LEC renewal. We design a surgical method of cataract removal that preserves endogenous LECs and achieves functional lens regeneration in rabbits and macaques, as well as in human infants with cataracts. Our method differs conceptually from current practice, as it preserves endogenous LECs and their natural environment maximally, and regenerates lenses with visual function. Our approach demonstrates a novel treatment strategy for cataracts and provides a new paradigm for tissue regeneration using endogenous stem cells.


Asunto(s)
Catarata/terapia , Cristalino/citología , Cristalino/fisiología , Recuperación de la Función , Regeneración/fisiología , Células Madre/citología , Visión Ocular/fisiología , Animales , Catarata/congénito , Catarata/patología , Catarata/fisiopatología , Extracción de Catarata , Células Epiteliales/citología , Células Epiteliales/metabolismo , Proteínas del Ojo/metabolismo , Proteínas de Homeodominio/metabolismo , Homeostasis , Humanos , Macaca , Factor de Transcripción PAX6 , Factores de Transcripción Paired Box/metabolismo , Complejo Represivo Polycomb 1/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Represoras/metabolismo , Células Madre/metabolismo
9.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(5): 530-535, 2022 May 15.
Artículo en Zh | MEDLINE | ID: mdl-35644193

RESUMEN

OBJECTIVES: To study the clinical features of intestinal polyps and the risk factors for secondary intussusception in children. METHODS: A retrospective analysis was performed for the medical data of 2 669 children with intestinal polyps. According to the presence or absence of secondary intussusception, they were divided into two groups: intussusception (n=346) and non-intussusception (n=2 323). Related medical data were compared between the two groups. The multivariate logistic regression analysis was used to identify the risk factors for secondary intussusception. RESULTS: Among the children with intestinal polyps, 62.42% were preschool children, and the male/female ratio was 2.08∶1; 92.66% had hematochezia as disease onset, and 94.34% had left colonic polyps and rectal polyps. There were 346 cases of secondary intussusception, with an incidence rate of 12.96% (346/2 669). Large polyps (OR=1.644, P<0.001), multiple polyps (≥2) (OR=6.034, P<0.001), and lobulated polyps (OR=93.801, P<0.001) were the risk factors for secondary intussusception. CONCLUSIONS: Intestinal polyps in children often occur in preschool age, mostly in boys, and most of the children have hematochezia as disease onset, with the predilection sites of the left colon and the rectum. Larger polyps, multiple polyps, and lobulated polyps may increase the risk of secondary intussusception, and endoscopic intervention is needed as early as possible to improve prognosis.


Asunto(s)
Intususcepción , Preescolar , Femenino , Hemorragia Gastrointestinal , Humanos , Pólipos Intestinales/complicaciones , Intususcepción/complicaciones , Masculino , Estudios Retrospectivos , Factores de Riesgo
10.
Eur Respir J ; 57(6)2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33303536

RESUMEN

Positive results in pre-clinical studies of the triple combination of elexacaftor, tezacaftor and ivacaftor, performed in airway epithelial cell cultures obtained from patients harbouring the class II cystic fibrosis transmembrane conductance regulator (CFTR) mutation F508del-CFTR, translated to impressive clinical outcomes for subjects carrying this mutation in clinical trials and approval of Trikafta.Encouraged by this correlation, we were prompted to evaluate the effect of the elexacaftor, tezacaftor and ivacaftor triple combination on primary nasal epithelial cultures obtained from individuals with rare class II CF-causing mutations (G85E, M1101K and N1303K) for which Trikafta is not approved.Cultures from individuals homozygous for M1101K responded better than cultures harbouring G85E and N1303K after treatment with the triple combination with respect to improvement in regulated channel function and protein processing. A similar genotype-specific effect of the triple combination was observed when the different mutations were expressed in HEK293 cells, supporting the hypothesis that these modulators may act directly on the mutant proteins. Detailed studies in nasal cultures and HEK293 cells showed that the corrector, elexacaftor, exhibited dual activity as both corrector and potentiator, and suggested that the potentiator activity contributes to its pharmacological activity.These pre-clinical studies using nasal epithelial cultures identified mutation genotypes for which elexacaftor, tezacaftor and ivacaftor may produce clinical responses that are comparable to, or inferior to, those observed for F508del-CFTR.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística , Fibrosis Quística , Aminofenoles , Benzodioxoles , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Combinación de Medicamentos , Células HEK293 , Humanos , Indoles , Mutación , Pirazoles , Piridinas , Pirrolidinas , Quinolinas , Quinolonas
11.
Exp Eye Res ; 205: 108491, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33587908

RESUMEN

This study aimed to investigate the protective effect of melatonin on the corneal epithelium in dry eye disease(DED) and explore its underlying mechanism. Human corneal epithelial(HCE) cells was exposure to t-butylhydroperoxide(tBH), C57BL/6 mice were injected of subcutaneous scopolamine to imitate DED. Melatonin was used both in vivo and in vitro. Cell viability was detected by Cell Counting Kit-8 assay and Lactate Dehydrogenase Leakage. The change of cellular reactive oxygen species (ROS) levels, mitochondrial membrane potential (MMP), and apoptosis was analyzed by flow cytometry. Western blot assays and immunofluorescence were carried out to measure protein changes. mRNA expression was investigated by RNA sequencing (RNA-Seq) and quantitative real-time PCR. The change of autophagic flux were observed through mCherry-GFP-LC3 transfection and electron microscopy(TEM). Clinical parameters of corneal epithelium defects, conjunctival goblet cells, tear volume, and level of ocular surface inflammation was recorded. Melatonin was able to reduce excessive ROS production and maintain mitochondrial function. TEM assay found melatonin rescued impaired autophagic flux under tBH. Moreover, melatonin significantly preserved cell viability, abolished LDH release, and decreased apoptosis. RNA-Seq indicated that melatonin greatly activating hemeoxygenase-1 (HO-1) expression. Interestingly, HO-1 ablation largely attenuated its protective effects. Besides, in dry eye mouse model, intraperitoneal injection of melatonin showed greatly improved clinical parameters, inhibited activated NLRP3 inflammation cascade, and increased density of goblet cells and tear volume. Thus, melatonin protects corneal epithelial cells from oxidative damage, maintain normal level of autophagy, and reduce inflammation via trigging HO-1 expression in DED.


Asunto(s)
Antioxidantes/uso terapéutico , Autofagia/efectos de los fármacos , Síndromes de Ojo Seco/tratamiento farmacológico , Hemo-Oxigenasa 1/metabolismo , Melatonina/uso terapéutico , Proteínas de la Membrana/metabolismo , Estrés Oxidativo/efectos de los fármacos , Animales , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Western Blotting , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Síndromes de Ojo Seco/inducido químicamente , Síndromes de Ojo Seco/metabolismo , Epitelio Corneal/efectos de los fármacos , Epitelio Corneal/metabolismo , Citometría de Flujo , Humanos , Melatonina/farmacología , Potencial de la Membrana Mitocondrial/fisiología , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Especies Reactivas de Oxígeno/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , terc-Butilhidroperóxido/farmacología
12.
BMC Endocr Disord ; 21(1): 118, 2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-34130666

RESUMEN

BACKGROUND: Most patients with congenital adrenal hypoplasia (AHC) develop symptoms during infantile and juvenile periods, with varying clinical manifestations. AHC is a disease that is easily misdiagnosed as Addison's disease or congenital adrenal hyperplasia (CAH). There was also a significant time difference between the age at which patients developed symptoms and the age at which they were diagnosed with AHC. Most patients showed early symptoms during infantile and juvenile periods, but were diagnosed with AHC many years later. CASE PRESENTATION: We are currently reporting a male patient who developed systemic pigmentation at age 2 and was initially diagnosed with Addison's disease. At 22 years of age, he experienced a slipped capital femoral epiphysis (SCFE), a disease mostly seen in adolescents aged 8-15 years, an important cause of which is endocrine disorder. Testes evaluated using color Doppler Ultrasonography suggested microcalcifications. Further genetic testing and auxiliary examinations revealed that the patient had hypogonadotropic hypogonadism (HH) and DAX-1 gene disorders, at which time he was diagnosed with AHC complicated by HH. He was given hormone replacement therapy, followed by regular outpatient review to adjust the medication. CONCLUSIONS: The typical early symptoms of AHC are hyperpigmentation and ion disturbance during infantile and juvenile periods, while few patients with AHC develop puberty disorders as early symptoms. AHC is prone to being misdiagnosed as Addison's disease, and then gradually develops the symptoms of HH in adolescence. The definitive diagnosis of AHC ultimately is based on the patient's clinical presentation, laboratory results and genetic testing results.


Asunto(s)
Hiperplasia Suprarrenal Congénita/patología , Receptor Nuclear Huérfano DAX-1/genética , Enfermedades Genéticas Ligadas al Cromosoma X/patología , Insuficiencia Corticosuprarrenal Familiar/patología , Hipogonadismo/patología , Mutación , Hiperplasia Suprarrenal Congénita/genética , Adulto , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Humanos , Insuficiencia Corticosuprarrenal Familiar/genética , Hipogonadismo/genética , Masculino , Pronóstico , Adulto Joven
13.
Nature ; 523(7562): 607-11, 2015 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-26200341

RESUMEN

The human lens is comprised largely of crystallin proteins assembled into a highly ordered, interactive macro-structure essential for lens transparency and refractive index. Any disruption of intra- or inter-protein interactions will alter this delicate structure, exposing hydrophobic surfaces, with consequent protein aggregation and cataract formation. Cataracts are the most common cause of blindness worldwide, affecting tens of millions of people, and currently the only treatment is surgical removal of cataractous lenses. The precise mechanisms by which lens proteins both prevent aggregation and maintain lens transparency are largely unknown. Lanosterol is an amphipathic molecule enriched in the lens. It is synthesized by lanosterol synthase (LSS) in a key cyclization reaction of a cholesterol synthesis pathway. Here we identify two distinct homozygous LSS missense mutations (W581R and G588S) in two families with extensive congenital cataracts. Both of these mutations affect highly conserved amino acid residues and impair key catalytic functions of LSS. Engineered expression of wild-type, but not mutant, LSS prevents intracellular protein aggregation of various cataract-causing mutant crystallins. Treatment by lanosterol, but not cholesterol, significantly decreased preformed protein aggregates both in vitro and in cell-transfection experiments. We further show that lanosterol treatment could reduce cataract severity and increase transparency in dissected rabbit cataractous lenses in vitro and cataract severity in vivo in dogs. Our study identifies lanosterol as a key molecule in the prevention of lens protein aggregation and points to a novel strategy for cataract prevention and treatment.


Asunto(s)
Catarata/tratamiento farmacológico , Catarata/metabolismo , Lanosterol/farmacología , Lanosterol/uso terapéutico , Agregado de Proteínas/efectos de los fármacos , Agregación Patológica de Proteínas/tratamiento farmacológico , Adulto , Secuencia de Aminoácidos , Amiloide/química , Amiloide/efectos de los fármacos , Amiloide/metabolismo , Amiloide/ultraestructura , Animales , Secuencia de Bases , Catarata/congénito , Catarata/genética , Catarata/patología , Línea Celular , Niño , Cristalinas/química , Cristalinas/genética , Cristalinas/metabolismo , Cristalinas/ultraestructura , Perros , Femenino , Humanos , Lanosterol/administración & dosificación , Cristalino/efectos de los fármacos , Cristalino/metabolismo , Cristalino/patología , Masculino , Modelos Moleculares , Datos de Secuencia Molecular , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Proteínas Mutantes/ultraestructura , Linaje , Agregación Patológica de Proteínas/patología
14.
Proc Natl Acad Sci U S A ; 115(17): E3987-E3995, 2018 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-29622681

RESUMEN

Oxidative stress (OS)-induced retinal pigment epithelium (RPE) cell apoptosis is critically implicated in the pathogenesis of age-related macular degeneration (AMD), a leading cause of blindness in the elderly. Heterochromatin, a compact and transcriptional inert chromatin structure, has been recently shown to be dynamically regulated in response to stress stimuli. The functional mechanism of heterochromatin on OS exposure is unclear, however. Here we show that OS increases heterochromatin formation both in vivo and in vitro, which is essential for protecting RPE cells from oxidative damage. Mechanistically, OS-induced heterochromatin selectively accumulates at p53-regulated proapoptotic target promoters and inhibits their transcription. Furthermore, OS-induced desumoylation of p53 promotes p53-heterochromatin interaction and regulates p53 promoter selection, resulting in the locus-specific recruitment of heterochromatin and transcription repression. Together, our findings demonstrate a protective function of OS-induced heterochromatin formation in which p53 desumoylation-guided promoter selection and subsequent heterochromatin recruitment play a critical role. We propose that targeting heterochromatin provides a plausible therapeutic strategy for the treatment of AMD.


Asunto(s)
Apoptosis , Silenciador del Gen , Heterocromatina/metabolismo , Estrés Oxidativo , Epitelio Pigmentado de la Retina/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Heterocromatina/genética , Heterocromatina/patología , Ratones , Ratones Noqueados , Epitelio Pigmentado de la Retina/patología , Sumoilación , Proteína p53 Supresora de Tumor/genética
15.
Eur Respir J ; 56(5)2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32457197

RESUMEN

Cystic fibrosis (CF) is a genetic disorder affecting multiple organs, including the pancreas, hepatobiliary system and reproductive organs; however, lung disease is responsible for the majority of morbidity and mortality. Management of CF involves CF transmembrane conductance regulator (CFTR) modulator agents including corrector drugs to augment cellular trafficking of mutant CFTR as well as potentiators that open defective CFTR channels. These therapies are poised to help most individuals with CF, with the notable exception of individuals with class I mutations where full-length CFTR protein is not produced. For these mutations, gene replacement has been suggested as a potential solution.In this work, we used a helper-dependent adenoviral vector (HD-CFTR) to express CFTR in nasal epithelial cell cultures derived from CF subjects with class I CFTR mutations.CFTR function was significantly restored in CF cells by HD-CFTR and reached healthy control functional levels as detected by Ussing chamber and membrane potential (FLIPR) assay. A dose-response relationship was observed between the amount of vector used and subsequent functional outcomes; small amounts of HD-CFTR were sufficient to correct CFTR function. At higher doses, HD-CFTR did not increase CFTR function in healthy control cells above baseline values. This latter observation allowed us to use this vector to benchmark in vitro efficacy testing of CFTR-modulator drugs.In summary, we demonstrate the potential for HD-CFTR to inform in vitro testing and to restore CFTR function to healthy control levels in airway cells with class I or CFTR nonsense mutations.


Asunto(s)
Fibrosis Quística , Fibrosis Quística/genética , Fibrosis Quística/terapia , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Células Epiteliales , Terapia Genética , Humanos , Mutación
16.
Nature ; 511(7509): 358-61, 2014 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-25030175

RESUMEN

The surface of the cornea consists of a unique type of non-keratinized epithelial cells arranged in an orderly fashion, and this is essential for vision by maintaining transparency for light transmission. Cornea epithelial cells (CECs) undergo continuous renewal from limbal stem or progenitor cells (LSCs), and deficiency in LSCs or corneal epithelium--which turns cornea into a non-transparent, keratinized skin-like epithelium--causes corneal surface disease that leads to blindness in millions of people worldwide. How LSCs are maintained and differentiated into corneal epithelium in healthy individuals and which key molecular events are defective in patients have been largely unknown. Here we report establishment of an in vitro feeder-cell-free LSC expansion and three-dimensional corneal differentiation protocol in which we found that the transcription factors p63 (tumour protein 63) and PAX6 (paired box protein PAX6) act together to specify LSCs, and WNT7A controls corneal epithelium differentiation through PAX6. Loss of WNT7A or PAX6 induces LSCs into skin-like epithelium, a critical defect tightly linked to common human corneal diseases. Notably, transduction of PAX6 in skin epithelial stem cells is sufficient to convert them to LSC-like cells, and upon transplantation onto eyes in a rabbit corneal injury model, these reprogrammed cells are able to replenish CECs and repair damaged corneal surface. These findings suggest a central role of the WNT7A-PAX6 axis in corneal epithelial cell fate determination, and point to a new strategy for treating corneal surface diseases.


Asunto(s)
Enfermedades de la Córnea/metabolismo , Enfermedades de la Córnea/patología , Epitelio Corneal/citología , Epitelio Corneal/metabolismo , Proteínas del Ojo/metabolismo , Proteínas de Homeodominio/metabolismo , Homeostasis , Factores de Transcripción Paired Box/metabolismo , Proteínas Represoras/metabolismo , Proteínas Wnt/metabolismo , Animales , Diferenciación Celular , Linaje de la Célula , Modelos Animales de Enfermedad , Epitelio Corneal/patología , Proteínas del Ojo/genética , Proteínas de Homeodominio/genética , Humanos , Limbo de la Córnea/citología , Limbo de la Córnea/metabolismo , Masculino , Factor de Transcripción PAX6 , Factores de Transcripción Paired Box/genética , Conejos , Proteínas Represoras/genética , Transducción de Señal , Piel/citología , Piel/metabolismo , Piel/patología , Trasplante de Células Madre , Células Madre/citología , Células Madre/metabolismo , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Proteínas Wnt/genética
17.
Endocr Pract ; 26(2): 207-217, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31652102

RESUMEN

Objective: The present study aimed to investigate the adverse effects of the antithyroid drugs propylthiouracil (PTU) and methimazole (MMI)/carbimazole (CMZ) in treating hyperthyroidism. Methods: Qualitative analysis was performed for studies identified in a literature search up to April 20, 2019, and 30 studies were selected for meta-analysis. The study designs included case-control, randomized controlled, and retrospective cohort. Patients were in four age groups: childhood, gestating mothers, older adults, and other ages, and all were receiving PTU or MMI/CMZ. Adverse reactions to MMI/CMZ and PTU were evaluated and compared. Results: Odds of liver function injury were higher in the PTU group than in the MMI/CMZ group (odds ratio [OR], 2.40; 95% confidence interval [CI], 1.16 to 4.96; P = .02). Odds of elevated transaminase were much higher in the PTU group than in the MMI/CMZ group (OR, 3.96; 95% CI, 2.49 to 6.28; P<.00001). No significant between-group differences were found in odds of elevated bilirubin, agranulocytosis, rash, or urticaria; incidence of other adverse events; or in children. Odds of birth defects during the first trimester of pregnancy were higher in the MMI/CMZ group than in the PTU group (OR, 1.29; 95% CI, 1.09 to 1.53; P = .003). Conclusion: The impact of PTU on liver injury and transaminase levels is greater than that of MMI/CMZ, but no significant between-group differences are found in the drugs' effects on bilirubin, agranulocytosis and rash, urticaria, or in children. In treating pregnancy-related hyperthyroidism, PTU should be used in the first trimester and MMI reserved for use in late pregnancy. Abbreviations: ALT = alanine aminotransferase; ATD = antithyroid drug; CI = confidence interval; CMZ = carbimazole; GD = Graves disease; MMI = methimazole; MTU = methylthiouracil; NOS = Newcastle-Ottawa Scale; OR = odds ratio; PTU = propylthiouracil; RAI = radioactive iodine.


Asunto(s)
Hipertiroidismo , Metimazol/uso terapéutico , Propiltiouracilo/uso terapéutico , Neoplasias de la Tiroides , Anciano , Antitiroideos , Niño , Femenino , Humanos , Hipertiroidismo/tratamiento farmacológico , Radioisótopos de Yodo , Embarazo , Estudios Retrospectivos
18.
Mol Pharmacol ; 96(4): 515-525, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31427400

RESUMEN

ORKAMBI, a combination of the corrector, lumacaftor, and the potentiator, ivacaftor, partially rescues the defective processing and anion channel activity conferred by the major cystic fibrosis-causing mutation, F508del, in in vitro studies. Clinically, the improvement in lung function after ORKAMBI treatment is modest and variable, prompting the search for complementary interventions. As our previous work identified a positive effect of arginine-dependent nitric oxide signaling on residual F508del-Cftr function in murine intestinal epithelium, we were prompted to determine whether strategies aimed at increasing arginine would enhance F508del-cystic fibrosis transmembrane conductance regulator (CFTR) channel activity in patient-derived airway epithelia. Now, we show that the addition of arginine together with inhibition of intracellular arginase activity increased cytosolic nitric oxide and enhanced the rescue effect of ORKAMBI on F508del-CFTR-mediated chloride conductance at the cell surface of patient-derived bronchial and nasal epithelial cultures. Interestingly, arginine addition plus arginase inhibition also enhanced ORKAMBI-mediated increases in ciliary beat frequency and mucociliary movement, two in vitro CF phenotypes that are downstream of the channel defect. This work suggests that strategies to manipulate the arginine-nitric oxide pathway in combination with CFTR modulators may lead to improved clinical outcomes. SIGNIFICANCE STATEMENT: These proof-of-concept studies highlight the potential to boost the response to cystic fibrosis (CF) transmembrane conductance regulator (CFTR) modulators, lumacaftor and ivacaftor, in patient-derived airway tissues expressing the major CF-causing mutant, F508del-CFTR, by enhancing other regulatory pathways. In this case, we observed enhancement of pharmacologically rescued F508del-CFTR by arginine-dependent, nitric oxide signaling through inhibition of endogenous arginase activity.


Asunto(s)
Aminofenoles/farmacología , Aminopiridinas/farmacología , Arginasa/antagonistas & inhibidores , Arginina/metabolismo , Benzodioxoles/farmacología , Fibrosis Quística/metabolismo , Óxido Nítrico/metabolismo , Quinolonas/farmacología , Animales , Bronquios/citología , Bronquios/efectos de los fármacos , Bronquios/metabolismo , Células Cultivadas , Fibrosis Quística/tratamiento farmacológico , Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Citosol/metabolismo , Combinación de Medicamentos , Humanos , Mucosa Intestinal/metabolismo , Ratones , Mutación , Nariz/citología , Nariz/efectos de los fármacos
19.
Exp Eye Res ; 180: 208-225, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30590023

RESUMEN

Ocular surface disease is one major type of eye diseases. Different etiologies trigger distinct pathological responses of the ocular surface. We previously reported that genetically engineered mice with ablation of Prickle 1 manifested precocious eyelid opening with ensuing cornea dysplasia. The current study aimed to characterize the molecular traits and the direct cause of ocular pathology associated with precocious eyelid opening in the Prickle 1 mutant mouse. Prickle 1 mutant mice exhibited a slew of ocular surface pathology including cell proliferation, cell fate transformation and inflammatory infiltration coinciding with the timing of the precocious eyelid opening. Forced eyelid opening in wild type mice did not induce cornea pathology comparable to that of the Prickle 1 mutants. Necrotic tissue debris was found associated with the lesioned cornea. RNAseq analysis of the mutant cornea revealed an expression profile shared by a range of dermatological diseases involving immune responses and cancer. Taken together, the data suggest that the necrotic eyelid debris plays an important role in ocular pathogenesis of the Prickle 1 mutant mouse, which may represent a type of non-infectious keratoconjunctivitis caused by damaged autologous tissues. Additionally, Prickle 1 mutant cornea pathogenesis may offer molecular insights into other types of epithelial pathogenesis.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Córnea/patología , Párpados/fisiología , Queratoconjuntivitis/genética , Proteínas con Dominio LIM/genética , Animales , Animales Recién Nacidos , Conjuntiva/patología , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/fisiología , Células Caliciformes/patología , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Queratoconjuntivitis/fisiopatología , Metaplasia , Ratones , Ratones Endogámicos C57BL , Necrosis/patología , Factor de Transcripción PAX6/genética , Reacción en Cadena en Tiempo Real de la Polimerasa
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