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1.
EMBO J ; 43(13): 2661-2684, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38811851

RESUMEN

The molecular mechanisms governing the response of hematopoietic stem cells (HSCs) to stress insults remain poorly defined. Here, we investigated effects of conditional knock-out or overexpression of Hmga2 (High mobility group AT-hook 2), a transcriptional activator of stem cell genes in fetal HSCs. While Hmga2 overexpression did not affect adult hematopoiesis under homeostasis, it accelerated HSC expansion in response to injection with 5-fluorouracil (5-FU) or in vitro treatment with TNF-α. In contrast, HSC and megakaryocyte progenitor cell numbers were decreased in Hmga2 KO animals. Transcription of inflammatory genes was repressed in Hmga2-overexpressing mice injected with 5-FU, and Hmga2 bound to distinct regions and chromatin accessibility was decreased in HSCs upon stress. Mechanistically, we found that casein kinase 2 (CK2) phosphorylates the Hmga2 acidic domain, promoting its access and binding to chromatin, transcription of anti-inflammatory target genes, and the expansion of HSCs under stress conditions. Notably, the identified stress-regulated Hmga2 gene signature is activated in hematopoietic stem progenitor cells of human myelodysplastic syndrome patients. In sum, these results reveal a TNF-α/CK2/phospho-Hmga2 axis controlling adult stress hematopoiesis.


Asunto(s)
Quinasa de la Caseína II , Cromatina , Proteína HMGA2 , Células Madre Hematopoyéticas , Ratones Noqueados , Proteína HMGA2/metabolismo , Proteína HMGA2/genética , Animales , Células Madre Hematopoyéticas/metabolismo , Ratones , Humanos , Quinasa de la Caseína II/metabolismo , Quinasa de la Caseína II/genética , Cromatina/metabolismo , Cromatina/genética , Factor de Necrosis Tumoral alfa/metabolismo , Hematopoyesis , Estrés Fisiológico , Fluorouracilo/farmacología , Regeneración , Fosforilación , Síndromes Mielodisplásicos/patología , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/metabolismo , Ratones Endogámicos C57BL
2.
PLoS Biol ; 21(6): e3002131, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37279234

RESUMEN

Orcinol glucoside (OG), mainly found in the rhizome of the traditional Chinese herb Curculigo orchioides Gaertn, is noted for its antidepressant effects. In this study, an efficient screening pipeline was established for identifying the highly active orcinol synthase (ORS) and UDP-dependent glycosyltransferase (UGT) involved in the biosynthesis of OG by combining transcriptome analysis, structure-based virtual screening, and in vitro enzyme activity assays. By enhancing the downstream pathway, metabolic engineering and fermentation optimization, the OG production in Yarrowia lipolytica was improved 100-fold, resulting in a final yield of 43.46 g/L (0.84 g/g DCW), which is almost 6,400-fold higher than the extraction yield from C. orchioides roots. This study provides a reference for rapid identification of functional genes and high-yield production of natural products.


Asunto(s)
Glucósidos , Yarrowia , Glucósidos/metabolismo , Yarrowia/genética , Ingeniería Metabólica/métodos , Fermentación
3.
Cereb Cortex ; 34(8)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39098820

RESUMEN

Drug addiction is a chronic and relapse brain disorder. Psychostimulants such as cocaine and amphetamine are highly addictive drugs. Abuse drugs target various brain areas in the nervous system. Recent studies have shown that the prefrontal cortex (PFC) plays a key role in regulating addictive behaviors. The PFC is made up of excitatory glutamatergic cells and gamma-aminobutyric acid (GABAergic) interneurons. Recently, studies showed that GABA level was related with psychostimulant addiction. In this review, we will introduce the role and mechanism of GABA and γ-aminobutyric acid receptors (GABARs) of the PFC in regulating drug addiction, especially in psychostimulant addiction.


Asunto(s)
Estimulantes del Sistema Nervioso Central , Corteza Prefrontal , Trastornos Relacionados con Sustancias , Ácido gamma-Aminobutírico , Corteza Prefrontal/metabolismo , Corteza Prefrontal/efectos de los fármacos , Humanos , Ácido gamma-Aminobutírico/metabolismo , Animales , Trastornos Relacionados con Sustancias/metabolismo , Estimulantes del Sistema Nervioso Central/farmacología , Receptores de GABA/metabolismo
4.
Cereb Cortex ; 34(7)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-39073381

RESUMEN

Cognitive impairment affects 29-67% of patients with neuromyelitis optica spectrum disorder. Previous studies have reported glutamate homeostasis disruptions in astrocytes, leading to imbalances in gamma-aminobutyric acid levels. However, the association between these neurotransmitter changes and cognitive deficits remains inadequately elucidated. Point RESolved Spectroscopy and Hadamard Encoding and Reconstruction of MEGA-Edited Spectroscopy techniques were utilized to evaluate gamma-aminobutyric acid, glutamate, glutathione levels, and excitation/inhibition balance in the anterior cingulate cortex, posterior cingulate cortex, and occipital cortex of 39 neuromyelitis optica spectrum disorder patients and 41 healthy controls. Cognitive function was assessed using neurocognitive scales. Results showed decreased gamma-aminobutyric acid levels alongside increased glutamate, glutathione, and excitation/inhibition ratio in the anterior cingulate cortex and posterior cingulate cortex of neuromyelitis optica spectrum disorder patients. Specifically, within the posterior cingulate cortex of neuromyelitis optica spectrum disorder patients, decreased gamma-aminobutyric acid levels and increased excitation/inhibition ratio correlated significantly with anxiety scores, whereas glutathione levels predicted diminished executive function. The results suggest that neuromyelitis optica spectrum disorder patients exhibit dysregulation in the GABAergic and glutamatergic systems in their brains, where the excitation/inhibition imbalance potentially acts as a neuronal metabolic factor contributing to emotional disorders. Additionally, glutathione levels in the posterior cingulate cortex region may serve as predictors of cognitive decline, highlighting the potential benefits of reducing oxidative stress to safeguard cognitive function in neuromyelitis optica spectrum disorder patients.


Asunto(s)
Ácido Glutámico , Giro del Cíngulo , Espectroscopía de Resonancia Magnética , Neuromielitis Óptica , Ácido gamma-Aminobutírico , Humanos , Giro del Cíngulo/metabolismo , Giro del Cíngulo/diagnóstico por imagen , Femenino , Adulto , Neuromielitis Óptica/metabolismo , Neuromielitis Óptica/diagnóstico por imagen , Masculino , Ácido Glutámico/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Persona de Mediana Edad , Ácido gamma-Aminobutírico/metabolismo , Glutatión/metabolismo , Adulto Joven , Neurotransmisores/metabolismo , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/diagnóstico por imagen
5.
Cell Mol Life Sci ; 81(1): 352, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39153043

RESUMEN

Parkinson's disease (PD) is the second most common neurodegenerative disease, and its hallmark pathological features are the loss of dopaminergic (DA) neurons in the midbrain substantia nigra pars compacta (SNpc) and the accumulation of alpha-synuclein (α-syn). It has been shown that the integrity of the blood-brain barrier (BBB) is damaged in PD patients, and a large number of infiltrating T cells and inflammatory cytokines have been detected in the cerebrospinal fluid (CSF) and brain parenchyma of PD patients and PD animal models, including significant change in the number and proportion of different CD4+ T cell subsets. This suggests that the neuroinflammatory response caused by CD4+ T cells is an important risk factor for the development of PD. Here, we systematically review the differentiation of CD4+ T cell subsets, and focus on describing the functions and mechanisms of different CD4+ T cell subsets and their secreted cytokines in PD. We also summarize the current immunotherapy targeting CD4+ T cells with a view to providing assistance in the diagnosis and treatment of PD.


Asunto(s)
Linfocitos T CD4-Positivos , Diferenciación Celular , Citocinas , Enfermedad de Parkinson , Enfermedad de Parkinson/patología , Enfermedad de Parkinson/inmunología , Enfermedad de Parkinson/metabolismo , Humanos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Animales , Citocinas/metabolismo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Barrera Hematoencefálica/inmunología , alfa-Sinucleína/metabolismo , alfa-Sinucleína/inmunología
6.
Nano Lett ; 24(37): 11393-11402, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39230971

RESUMEN

Sodium ion batteries (SIBs) are promising postlithium battery technologies with high safety and low cost. However, their development is hampered by complicated electrode material preparation and unsatisfactory sodium storage performance. Here, a bismuth/N-doped carbon nanosheets (Bi/N-CNSs) composite featuring a quasi-array structure (alternated porous Bi layers and N-CNSs) with hierarchical Bi distribution (large particles of ∼35 nm in Bi layers and ultrafine Bi of ∼8 nm on N-CNSs) is prepared. Bi/N-CNSs delivers an ultralong-lifespan of 26000 cycles at 5 A g-1 and prominent rate capability of 91.5% capacity retention at 100 A g-1. Even at -40 °C, it exhibits a high rate capability of 161 mAh g-1 at 5 A g-1. Notably, the involved preparation method is characterized by a high yield of 14.53 g in a single laboratory batch, which can be further scaled up, and such a method can also be extended to synthesize other metallic-based materials.

7.
Mol Med ; 30(1): 142, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251914

RESUMEN

Oxidative damage to human retinal pigment epithelial (RPE) cells is the main cause of age-related macular degeneration (AMD), in our previous work, we showed that ghrelin has an antioxidative effect on human lens epithelium (HLE) cells, however, the studies of using ghrelin in treating the degenerative diseases of the retina have rarely been reported. In this article, we assessed the effect of ghrelin on preventing oxidative stress induced by hydrogen peroxide (H2O2) in ARPE-19 cells and its mechanism. We observed that pretreatment with ghrelin protected ARPE-19 cells from H2O2-induced cell oxidative injuries and apoptosis responses. Furthermore, an oxidative stress-induced mouse model of AMD was established via injection of sodium iodate (NaIO3) to tail veins, and treatment with ghrelin preserved retinal function, and protected photoreceptors.


Asunto(s)
Apoptosis , Modelos Animales de Enfermedad , Ghrelina , Peróxido de Hidrógeno , Degeneración Macular , Estrés Oxidativo , Epitelio Pigmentado de la Retina , Estrés Oxidativo/efectos de los fármacos , Degeneración Macular/etiología , Degeneración Macular/metabolismo , Degeneración Macular/tratamiento farmacológico , Degeneración Macular/prevención & control , Animales , Ghrelina/farmacología , Ghrelina/metabolismo , Humanos , Ratones , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/efectos de los fármacos , Línea Celular , Apoptosis/efectos de los fármacos , Yodatos , Antioxidantes/farmacología , Ratones Endogámicos C57BL , Masculino
8.
Small ; 20(27): e2306616, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38342672

RESUMEN

Metal-organic frameworks (MOFs) are crystalline porous materials with a long-range ordered structure and excellent specific surface area and have found a wide range of applications in diverse fields, such as catalysis, energy storage, sensing, and biomedicine. However, their poor electrical conductivity and chemical stability, low capacity, and weak adhesion to substrates have greatly limited their performance. Doping has emerged as a unique strategy to mitigate the issues. In this review, the concept, classification, and characterization methods of doped MOFs are first introduced, and recent progress in the synthesis and applications of doped MOFs, as well as the rapid advancements and applications of first-principles calculations based on the density functional theory (DFT) in unraveling the mechanistic origin of the enhanced performance are summarized. Finally, a perspective is included to highlight the key challenges in doping MOF materials and an outlook is provided on future research directions.

9.
Am Heart J ; 275: 53-61, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38838969

RESUMEN

BACKGROUND: The previous first-in-human study established the preliminary safety and effectiveness of the novel thin-strut iron bioresorbable scaffold (IBS). The current study aims to directly compare the imaging and physiological efficacy, and clinical outcomes of IBS with contemporary metallic drug-eluting stents (DES). METHODS: A total of 518 patients were randomly allocated to treatment with IBS (257 patients) or metallic DES (261 patients) from 36 centers in China. The study is powered to test noninferiority of the IBS compared with the metallic everolimus-eluting stent in terms of the primary endpoint of in-segment late lumen loss at 2 years, and major secondary endpoints including 2-year quantitative flow ratio and cross-sectional mean flow area measured by optical coherence tomography (OCT) (limited to the OCT subgroup, 25 patients in each group). CONCLUSION: This will be the first powered randomized trial investigating the safety and efficacy of the novel thin-strut IBS compared to a contemporary metallic DES. The findings will provide valuable evidence for future research of this kind and the application of metallic bioresorbable scaffolds.


Asunto(s)
Implantes Absorbibles , Enfermedad de la Arteria Coronaria , Stents Liberadores de Fármacos , Everolimus , Sirolimus , Tomografía de Coherencia Óptica , Humanos , Everolimus/administración & dosificación , Everolimus/farmacología , Enfermedad de la Arteria Coronaria/terapia , Enfermedad de la Arteria Coronaria/cirugía , Sirolimus/análogos & derivados , Sirolimus/administración & dosificación , Sirolimus/farmacología , Tomografía de Coherencia Óptica/métodos , Masculino , Femenino , Persona de Mediana Edad , Diseño de Prótesis , Hierro , Andamios del Tejido , Intervención Coronaria Percutánea/métodos , Inmunosupresores/administración & dosificación , Inmunosupresores/farmacología , Resultado del Tratamiento
10.
J Transl Med ; 22(1): 155, 2024 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-38360728

RESUMEN

BACKGROUND: Hypertension influences the inflammatory pathological changes in the retina. The function of the inflammasomes is significant. To see if Sirtuin 1 (SIRT1) regulates angiotensin II (Ang II)-induced hypertensive retinopathy and inflammation by modulating NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome activation and the potential protective effects of fucoidan (FO) in mouse retinal vascular endothelial cells (mRECs) and mice retina. METHODS: The diagnosis of hypertensive retinopathy was made after three weeks of Ang II infusion (3000 ng/kg/min). One day prior to the commencement of Ang II infusion, the mice were treatment with NLRP3 inhibitor MCC950 (10 mg/kg/day, intraperitoneal injections) or FO (300 mg/kg/day, oral gavage). A blood pressure was recorded. Hematoxylin and eosin (H&E) staining was used to conduct pathological alterations, dihydroethidium bromide (DHE) was utilized to assess oxidative stress damage in the retina, and fluorescence angiography was used to identify vascular disorders in the eye. Using immunohistochemical labeling, NLRP3 expression was found. Reactive protein and mRNA expression levels in mouse retina and cells were assessed using Western blot and real-time quantitative polymerase chain reaction (RT-qPCR). RESULTS: NLRP3 inflammasome activation and SIRT1 decrease were brought about by Ang II infusion. Retinopathy and dysfunction were lessened by MCC950 target-induced NLRP3 inflammasome activation, while overexpression of SIRT1 had the opposite impact on NLRP3 inflammasome activation, indicating that SIRT1 functions as an upstream regulator of NLRP3 activity. FO may improve SIRT1 expression and decrease NLRP3 activation in retinopathy and dysfunction brought on by Ang II, and the effects were consistent across both in vivo and in vitro models. CONCLUSIONS: SIRT1 adversely regulates the NLRP3 inflammasome pathway, which in turn increases Ang II-induced inflammation and hypertensive retinopathy. FO may mitigate Ang II-induced retinopathy and dysfunction via modulating the expression of SIRT1/NLRP3. This implies practical approaches to the management of hypertensive retinopathy.


Asunto(s)
Retinopatía Hipertensiva , Proteína con Dominio Pirina 3 de la Familia NLR , Polisacáridos , Ratones , Animales , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Inflamasomas/metabolismo , Sirtuina 1/metabolismo , Células Endoteliales/metabolismo , Inflamación , Angiotensina II
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