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1.
iScience ; 27(9): 110801, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39310777

RESUMEN

Extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) for the treatment of bone defects have been widely reported as a cell-free therapy because of their appropriate stability and biocompatibility. However, EV isolation is expensive and time-consuming. We developed a method of modifying EVs derived from bone marrow MSCs (BMSCs) via the cationic polymer (ERP) with characteristics of charge reversal and esterase response (ERP-EVs). When simply mixing BMSCs-EVs with ERP at a 1:1 ratio, ERP-EVs significantly enhanced the osteogenesis of BMSCs. More EVs were released by ERP in BMSCs than in fibroblasts, realizing the selective release. Last, ERP-EVs were loaded on an nHA/CS-MS scaffold and showed enhanced bone regeneration on rat calvarial bone defects in vivo. In general, this study provided an effective strategy to improve cellular uptake and selective release of BMSCs-EVs in bone-related cells, which had great potential to accelerate the clinical practice of BMSCs-EVs-based bone defect repair.

2.
Cell Signal ; 124: 111401, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39260533

RESUMEN

Studies have shown that Small conductance Ca2 + -activated K+ (SK) channel are expressed in fibroblasts. We aimed to determine the expression of SK2 channels in cardiac fibroblasts during myocardial hypertrophy and investigate its relationship with fibrotic remodeling. Myocardial hypertrophy and fibrotic remodeling induced by transverse aortic constriction (TAC) were assessed by echocardiography, Masson's trichrome staining and Western blot. Knockdown and overexpression of the SK2 protein were used to assess relationship between SK2 expression in fibroblasts and myocardial fibrosis. There is a positive correlation between myocardial fibrosis and SK2 channel protein expression during the development of myocardial hypertrophy. The differentiation and secretion of fibroblasts in mice with cardiac hypertrophy are enhanced, and the expression of SK2 channel protein is increased. Manipulating SK2 levels in fibroblasts can either promote or inhibit their differentiation and secretory function. Knocking down SK2 reduces the up-regulation of TGF ß1, p-Smad2/3/GAPDH, p-p38/GAPDH, p-ERK1/2/GAPDH, and p-JNK/GAPDH proteins induced by Ang II in cardiac fibroblasts without significantly affecting total protein levels. AAV9-SK2-RNAi injection in mice improves cardiac function. Collectively, our study suggests that the expression of the SK2 channel is significantly increased in fibroblasts of mice with myocardial hypertrophy, potentially impacting myocardial fibrosis remodeling via the TGF-ß signaling pathway.

3.
Signal Transduct Target Ther ; 9(1): 230, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39237509

RESUMEN

Cardiac biological pacing (BP) is one of the future directions for bradyarrhythmias intervention. Currently, cardiac pacemaker cells (PCs) used for cardiac BP are mainly derived from pluripotent stem cells (PSCs). However, the production of high-quality cardiac PCs from PSCs remains a challenge. Here, we developed a cardiac PC differentiation strategy by adopting dual PC markers and simulating the developmental route of PCs. First, two PC markers, Shox2 and Hcn4, were selected to establish Shox2:EGFP; Hcn4:mCherry mouse PSC reporter line. Then, by stepwise guiding naïve PSCs to cardiac PCs following naïve to formative pluripotency transition and manipulating signaling pathways during cardiac PCs differentiation, we designed the FSK method that increased the yield of SHOX2+; HCN4+ cells with typical PC characteristics, which was 12 and 42 folds higher than that of the embryoid body (EB) and the monolayer M10 methods respectively. In addition, the in vitro cardiac PCs differentiation trajectory was mapped by single-cell RNA sequencing (scRNA-seq), which resembled in vivo PCs development, and ZFP503 was verified as a key regulator of cardiac PCs differentiation. These PSC-derived cardiac PCs have the potential to drive advances in cardiac BP technology, help with the understanding of PCs (patho)physiology, and benefit drug discovery for PC-related diseases as well.


Asunto(s)
Diferenciación Celular , Miocitos Cardíacos , Células Madre Pluripotentes , Animales , Ratones , Diferenciación Celular/genética , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/citología , Células Madre Pluripotentes/metabolismo , Células Madre Pluripotentes/citología , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización/genética , Canales Regulados por Nucleótidos Cíclicos Activados por Hiperpolarización/metabolismo , Cuerpos Embrioides/citología , Cuerpos Embrioides/metabolismo
4.
Cell Rep ; 43(8): 114622, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39146182

RESUMEN

Microsatellite instability-high (MSI-H) tumors are malignant tumors that, despite harboring a high mutational burden, often have intact TP53. One of the most frequent mutations in MSI-H tumors is a frameshift mutation in RPL22, a ribosomal protein. Here, we identified RPL22 as a modulator of MDM4 splicing through an alternative splicing switch in exon 6. RPL22 loss increases MDM4 exon 6 inclusion and cell proliferation and augments resistance to the MDM inhibitor Nutlin-3a. RPL22 represses the expression of its paralog, RPL22L1, by mediating the splicing of a cryptic exon corresponding to a truncated transcript. Therefore, damaging mutations in RPL22 drive oncogenic MDM4 induction and reveal a common splicing circuit in MSI-H tumors that may inform therapeutic targeting of the MDM4-p53 axis and oncogenic RPL22L1 induction.


Asunto(s)
Proteínas de Ciclo Celular , Proteínas Ribosómicas , Humanos , Proteínas Ribosómicas/metabolismo , Proteínas Ribosómicas/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/genética , Neoplasias/genética , Neoplasias/patología , Neoplasias/metabolismo , Línea Celular Tumoral , Empalme Alternativo/genética , Proliferación Celular/genética , Animales , Exones/genética , Ratones , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Regulación Neoplásica de la Expresión Génica , Piperazinas/farmacología , Imidazoles/farmacología
5.
Theranostics ; 14(11): 4331-4351, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39113801

RESUMEN

Background: The impediment to ß-amyloid (Aß) clearance caused by the invalid intracranial lymphatic drainage in Alzheimer's disease is pivotal to its pathogenesis, and finding reliable clinical available solutions to address this challenge remains elusive. Methods: The potential role and underlying mechanisms of intranasal oxytocin administration, an approved clinical intervention, in improving intracranial lymphatic drainage in middle-old-aged APP/PS1 mice were investigated by live mouse imaging, ASL/CEST-MRI scanning, in vivo two-photon imaging, immunofluorescence staining, ELISA, RT-qPCR, Western blotting, RNA-seq analysis, and cognitive behavioral tests. Results: Benefiting from multifaceted modulation of cerebral hemodynamics, aquaporin-4 polarization, meningeal lymphangiogenesis and transcriptional profiles, oxytocin administration normalized the structure and function of both the glymphatic and meningeal lymphatic systems severely impaired in middle-old-aged APP/PS1 mice. Consequently, this intervention facilitated the efficient drainage of Aß from the brain parenchyma to the cerebrospinal fluid and then to the deep cervical lymph nodes for efficient clearance, as well as improvements in cognitive deficits. Conclusion: This work broadens the underlying neuroprotective mechanisms and clinical applications of oxytocin medication, showcasing its promising therapeutic prospects in central nervous system diseases with intracranial lymphatic dysfunction.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Modelos Animales de Enfermedad , Sistema Glinfático , Ratones Transgénicos , Oxitocina , Animales , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Ratones , Oxitocina/farmacología , Oxitocina/administración & dosificación , Oxitocina/metabolismo , Sistema Glinfático/metabolismo , Sistema Glinfático/efectos de los fármacos , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Encéfalo/efectos de los fármacos , Encéfalo/diagnóstico por imagen , Administración Intranasal , Linfangiogénesis/efectos de los fármacos , Masculino , Acuaporina 4/metabolismo , Acuaporina 4/genética , Humanos , Imagen por Resonancia Magnética , Meninges/metabolismo , Meninges/efectos de los fármacos , Meninges/diagnóstico por imagen
6.
Sci Total Environ ; 951: 175548, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39151624

RESUMEN

Recent research on fluoride in water primarily focuses on groundwater; however, the potential environmental risks of fluoride in urban rivers should not be overlooked. In 2023, this study collected 135 surface water samples from the Ershibu River in Hefei, China, during various flood periods. Through descriptive statistical analysis, correlation analysis, principal component analysis-multiple linear regression (PCA-MLR) modeling, hazard quotient (HQ) assessment, and Monte Carlo simulation analysis, the spatial and temporal distribution, potential sources, and health risks of fluoride were investigated. The results showed that fluoride concentrations in the Ershibu River ranged from 0 to 1.38 mg/L. According to the PCA-MLR calculations, industrial pollution (73.92 %) was identified as the main source, followed by hydrogeochemical evolution (16.10 %) and agricultural activities (9.98 %). The HQ analysis revealed that the average exceedance rates of HQ for the five exposed populations were as follows: infants (64.45 %) > young children (2.22 %) = adults (2.22 %) > children (0) = teenagers (0). Therefore, relevant authorities should improve defluoridation facilities to reduce fluoride levels in industrial and agricultural wastewater and implement measures to protect public health. Future research should investigate the migration processes and toxicity mechanisms of fluoride more thoroughly.

7.
Int J Biol Macromol ; 278(Pt 2): 134868, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39163965

RESUMEN

Food allergy (FA) has increasingly attracted global attention in past decades. However, the mechanism and effect of FA are complex and varied, rendering it hard to prevention and management. Most of the allergens identified so far are macromolecular proteins in food and may have potential cross-reactions. Human milk oligosaccharides (HMOs) have been regarded as an ideal nutrient component for infants, as they can enhance the immunomodulatory capacity to inhibit the progress of FA. HMOs may intervene in the development of allergies by modifying gut microbiota and increasing specific short-chain fatty acids levels. Additionally, HMOs could improve the intestinal permeability and directly or indirectly regulate the balance of T helper cells and regulatory T cells by enhancing the inflammatory signaling pathways to combat FA. This review will discuss the influence factors of FA, key species of gut microbiota involved in FA, types of FA, and profiles of HMOs and provide evidence for future research trends to advance HMOs as potential therapeutic aids in preventing the progress of FA.


Asunto(s)
Hipersensibilidad a los Alimentos , Microbioma Gastrointestinal , Leche Humana , Oligosacáridos , Humanos , Microbioma Gastrointestinal/efectos de los fármacos , Oligosacáridos/farmacología , Oligosacáridos/uso terapéutico , Leche Humana/inmunología , Leche Humana/química , Hipersensibilidad a los Alimentos/prevención & control , Hipersensibilidad a los Alimentos/inmunología , Hipersensibilidad a los Alimentos/microbiología , Inmunomodulación/efectos de los fármacos , Animales
8.
J Inorg Biochem ; 260: 112690, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39126756

RESUMEN

Complexes [Cu(PI)2(H2O)](NO3)2 (1), [Cu(PBI)2(NO3)]NO3 (2), [Cu(TBI)2(NO3)]NO3 (3), [Cu(BBIP)2](ClO4)2 (4) and [Cu(BBIP)(CH3OH)(ClO4)2] (5) were synthesized from the reactions of Cu(II) salts with 2-(2'-pyridyl)imidazole (PI), (2-(2'-pyridyl)benzimidazole (PBI), 2-(4'-thiazolyl)-benzimidazole (TBI), 2,6-bis(benzimidazol-2-yl)-pyridine (BBIP), respectively. Their compositions and crystal structures were determined. Their in-vitro antitumor activities were screened on four cancer cell lines and one normal cell line (HL-7702) using cisplatin as the positive control. Complexes 2 and 4 show higher cytotoxicity than the other three complexes. The cytotoxicity of complex 2 are comparable to those for cisplatin, and the cytotoxicity for 4 are much higher than those for cisplatin. From a viewpoint of antitumor, 2 might be a nice choice on the tumor cell line of T24 because its IC50 values on T24 and HL-7702 are 15.03 ± 1.10 and 21.34 ± 0.35, respectively. Thus, a mechanistic study for complexes 2 and 4 on T24 cells was conducted. It revealed that they can reduce mitochondrial membrane potential and increase mitochondrial membrane permeability, resulting in increased intracellular ROS levels, Ca2+ inward flow, dysfunctional mitochondria and the eventual cell apoptosis. In conclusion, they can induce cell apoptosis through mitochondrial dysfunction. These findings could be useful in the development of new antitumor agents.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Cobre , Imidazoles , Humanos , Cobre/química , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Imidazoles/química , Imidazoles/farmacología , Imidazoles/síntesis química , Complejos de Coordinación/farmacología , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , Línea Celular Tumoral , Apoptosis/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Bencimidazoles/farmacología , Bencimidazoles/química , Bencimidazoles/síntesis química
9.
Nat Commun ; 15(1): 6396, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080288

RESUMEN

In plants, the conserved plant-specific photoreceptor UV RESISTANCE LOCUS 8 (UVR8) perceives ultraviolet-B (UV-B) light and mediates UV-B-induced photomorphogenesis and stress acclimation. In this study, we reveal that UV-B light treatment shortens seedlings, increases stem thickness, and enhances UV-B stress tolerance in rice (Oryza sativa) via its two UV-B photoreceptors OsUVR8a and OsUVR8b. Although the rice and Arabidopsis (Arabidopsis thaliana) UVR8 (AtUVR8) photoreceptors all form monomers in response to UV-B light, OsUVR8a, and OsUVR8b function is only partially conserved with respect to AtUVR8 in UV-B-induced photomorphogenesis and stress acclimation. UV-B light and CONSTITUTIVELY PHOTOMORPHOGENIC 1 (COP1) promote the nuclear accumulation of AtUVR8; by contrast, OsUVR8a and OsUVR8b constitutively localize to the nucleus via their own nuclear localization signals, independently of UV-B light and the RING-finger mutation of OsCOP1. We show that OsCOP1 negatively regulates UV-B responses, and shows weak interaction with OsUVR8s, which is ascribed to the N terminus of OsCOP1, which is conserved in several monocots. Furthermore, transcriptome analysis demonstrates that UV-B-responsive gene expression differs globally between Arabidopsis and rice, illuminating the evolutionary divergence of UV-B light signaling pathways between monocot and dicot plants.


Asunto(s)
Arabidopsis , Núcleo Celular , Regulación de la Expresión Génica de las Plantas , Oryza , Proteínas de Plantas , Rayos Ultravioleta , Oryza/metabolismo , Oryza/genética , Oryza/efectos de la radiación , Núcleo Celular/metabolismo , Núcleo Celular/efectos de la radiación , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Arabidopsis/efectos de la radiación , Arabidopsis/metabolismo , Arabidopsis/genética , Fotorreceptores de Plantas/metabolismo , Fotorreceptores de Plantas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Plantones/efectos de la radiación , Plantones/metabolismo , Plantones/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Mutación , Plantas Modificadas Genéticamente , Proteínas Cromosómicas no Histona/metabolismo , Proteínas Cromosómicas no Histona/genética
10.
Food Chem ; 459: 140346, 2024 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38981378

RESUMEN

Phyllanthus emblica L. offers promising therapeutic potential for inflammatory diseases. This study revealed the molecular structure of a homogeneous polysaccharide purified from Phyllanthus emblica L. (PEP-1) and evaluated its anti-inflammatory effects on ulcerative colitis (UC) in mice. In the in vivo experiment, administered in varying dosages to dextran sulfate sodium (DSS)-induced UC models, PEP-1 significantly alleviated colonic symptoms, histological damages and reshaped the gut microbiota. Notably, it adjusted the Firmicutes/Bacteroidetes ratio and reduced pro-inflammatory species, closely aligning with shifts in the fecal metabolites and metabolic pathways such as the metabolism of pyrimidine, beta-alanine, and purine. These findings underscore the potential of PEP-1 as a therapeutic agent for UC, providing insights into the mechanisms through gut microbiota and metabolic modulation.


Asunto(s)
Antiinflamatorios , Bacterias , Colitis Ulcerosa , Sulfato de Dextran , Microbioma Gastrointestinal , Phyllanthus emblica , Extractos Vegetales , Polisacáridos , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Ratones , Sulfato de Dextran/efectos adversos , Polisacáridos/farmacología , Polisacáridos/química , Polisacáridos/administración & dosificación , Polisacáridos/aislamiento & purificación , Phyllanthus emblica/química , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/administración & dosificación , Masculino , Humanos , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/microbiología , Colitis Ulcerosa/metabolismo , Bacterias/clasificación , Bacterias/aislamiento & purificación , Bacterias/efectos de los fármacos , Bacterias/genética , Extractos Vegetales/farmacología , Extractos Vegetales/química , Extractos Vegetales/administración & dosificación , Ratones Endogámicos C57BL , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/metabolismo , Colitis/microbiología , Modelos Animales de Enfermedad , Colon/microbiología , Colon/efectos de los fármacos , Colon/metabolismo , Colon/inmunología
11.
Water Res ; 262: 122079, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39047454

RESUMEN

The massive use and discharge of antibiotics have led to increasing concerns about antimicrobial resistance (AMR) in natural aquatic environments. Since the dose-response mechanisms of pathogens with AMR have not yet been fully understood, and the antibiotic resistance genes and bacteria-related data collection via field sampling and laboratory testing is time-consuming and expensive, designing a rapid approach to quantify the burden of AMR in the natural aquatic environment has become a challenge. To cope with such a challenge, a new approach involving an integrated machine-learning framework was developed by investigating the associations between the relative burden of AMR and easily accessible variables (i.e., relevant environmental variables and adjacent land-use patterns). The results, based on a real-world case analysis, demonstrate that the quantification speed has been reduced from 3-7 days, which is typical for traditional measurement procedures with field sampling and laboratory testing, to approximately 0.5 hours using the new approach. Moreover, all five metrics for AMR relative burden quantification exceed the threshold level of 85%, with F1-score surpassing 0.92. Compared to logistic regression, decision trees, and basic random forest, the adaptive random forest model within the framework significantly improves quantification accuracy without sacrificing model interpretability. Two environmental variables, dissolved oxygen and resistivity, along with the proportion of green areas were identified as three key feature variables for the rapid quantification. This study contributes to the enrichment of burden analyses and management practices for rapid quantification of the relative burden of AMR without dose-response information.


Asunto(s)
Aprendizaje Automático , Antibacterianos/farmacología , Farmacorresistencia Microbiana/genética , Monitoreo del Ambiente/métodos
12.
Food Chem ; 460(Pt 1): 140562, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39059324

RESUMEN

With the increasing demand for meat products, the evaluation and real-time monitoring of its freshness has become one of the focuses of related industry research. Conventional freshness detection methods, including sensory evaluation, microbial experiments, and determination of physicochemical indicators, are time-consuming, low sensitivity, and destructive, so there is an urgent need to develop a convenient, intuitive, and inexpensive detection method. As a representative of smart packaging, visual intelligent labels can realize real-time perception and monitoring of meat freshness by measuring the temperature, pH value or other indicators of meat and converting them into visual signals. This paper first summarizes the common types, basic principles and research progress of visual intelligent labels, then introduces its application in livestock, poultry and seafood freshness monitoring, finally looks forward to the development prospect of visual smart labels.


Asunto(s)
Carne , Animales , Carne/análisis , Etiquetado de Alimentos , Aves de Corral , Ganado , Embalaje de Alimentos/instrumentación , Concentración de Iones de Hidrógeno , Alimentos Marinos/análisis , Productos de la Carne/análisis , Temperatura
13.
J Adv Res ; 2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38862035

RESUMEN

INTRODUCTION: Frailty Index (FI) is a common measure of frailty, which has been advocated as a routine clinical test by many guidelines. The genetic and phenotypic relationships of FI with cardiovascular indicators (CIs) and behavioral characteristics (BCs) are unclear, which has hampered ability to monitor FI using easily collected data. OBJECTIVES: This study is designed to investigate the genetic and phenotypic associations of frailty with CIs and BCs, and further to construct a model to predict FI. METHOD: Genetic relationships of FI with 288 CIs and 90 BCs were assessed by the cross-trait LD score regression (LDSC) and Mendelian randomization (MR). The phenotypic data of these CIs and BCs were integrated with a machine-learning model to predict FI of individuals in UK-biobank. The relationships of the predicted FI with risks of type 2 diabetes (T2D) and neurodegenerative diseases were tested by the Kaplan-Meier estimator and Cox proportional hazards model. RESULTS: MR revealed putative causal effects of seven CIs and eight BCs on FI. These CIs and BCs were integrated to establish a model for predicting FI. The predicted FI is significantly correlated with the observed FI (Pearson correlation coefficient = 0.660, P-value = 4.96 × 10-62). The prediction model indicated "usual walking pace" contributes the most to prediction. Patients who were predicted with high FI are in significantly higher risk of T2D (HR = 2.635, P < 2 × 10-16) and neurodegenerative diseases (HR = 2.307, P = 1.62 × 10-3) than other patients. CONCLUSION: This study supports associations of FI with CIs and BCs from genetic and phenotypic perspectives. The model that is developed by integrating easily collected CIs and BCs data in predicting FI has the potential to monitor disease risk.

14.
ACS Synth Biol ; 13(6): 1879-1892, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38847341

RESUMEN

Aromatic d-amino acids (d-AAs) play a pivotal role as important chiral building blocks and key intermediates in fine chemical and drug synthesis. Meso-diaminopimelate dehydrogenase (DAPDH) serves as an excellent biocatalyst in the synthesis of d-AAs and their derivatives. However, its strict substrate specificity and the lack of efficient engineering methods have hindered its widespread application. Therefore, this study aims to elucidate the catalytic mechanism underlying DAPDH from Proteus vulgaris (PvDAPDH) through the examination of its crystallographic structure, computational simulations of potential energies and molecular dynamics simulations, and site-directed mutagenesis. Mechanism-guided computational design showed that the optimal mutant PvDAPDH-M3 increased specific activity and catalytic efficiency (kcat/Km) for aromatic keto acids up to 124-fold and 92.4-fold, respectively, compared to that of the wild type. Additionally, it expanded the substrate scope to 10 aromatic keto acid substrates. Finally, six high-value-added aromatic d-AAs and their derivatives were synthesized using a one-pot three-enzyme cascade reaction, exhibiting a good conversion rate ranging from 32 to 84% and excellent stereoselectivity (enantiomeric excess >99%). These findings provide a potential synthetic pathway for the green industrial production of aromatic d-AAs.


Asunto(s)
Aminoácido Oxidorreductasas , Aminoácidos Aromáticos , Simulación de Dinámica Molecular , Mutagénesis Sitio-Dirigida , Aminoácido Oxidorreductasas/metabolismo , Aminoácido Oxidorreductasas/genética , Aminoácido Oxidorreductasas/química , Especificidad por Sustrato , Aminoácidos Aromáticos/metabolismo , Aminoácidos Aromáticos/biosíntesis , Proteus vulgaris/enzimología , Proteus vulgaris/genética , Biocatálisis , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química
15.
bioRxiv ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38853975

RESUMEN

The Iroquois (Iro/Irx) homeobox genes encode transcription factors with fundamental roles in animal development. Despite their link to various congenital conditions in humans, our understanding of Iro/Irx gene expression, function, and regulation remains incomplete. Here, we conducted a systematic expression analysis of all six mouse Irx genes in the embryonic spinal cord. We found five Irx genes (Irx1, Irx2, Irx3, Irx5, and Irx6) to be confined mostly to ventral spinal domains, offering new molecular markers for specific groups of post-mitotic motor neurons (MNs). Further, we engineered Irx2, Irx5, and Irx6 mouse mutants and uncovered essential but distinct roles for Irx2 and Irx6 in MN development. Last, we found that the highly conserved regulators of MN development across species, the HOX proteins, directly control Irx gene expression both in mouse and C. elegans MNs, critically expanding the repertoire of HOX target genes in the developing nervous system. Altogether, our study provides important insights into Iro/Irx expression and function in the developing spinal cord, and uncovers an ancient gene regulatory relationship between HOX and Iro/Irx genes.

16.
Res Sq ; 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38883711

RESUMEN

Background: Genetic mitochondrial diseases are a major challenge in modern medicine, impacting around 1:4,000 individuals. Leigh syndrome is the most common pediatric presentation of mitochondrial disease. There are currently no effective clinical treatments for mitochondrial disease. In humans, patients are often treated with antioxidants, vitamins, and strategies targeting energetics. The vitamin-E related compound vatiquinone (EPI-743, α-tocotrienol quinone) has been the subject of at least 19 clinical trials in the US since 2012, but the effects of vatiquinone on an animal model of mitochondrial disease have not yet been reported. Here, assessed the impact of vatiquinone on disease progression and in two animal models of mitochondrial disease. Methods: The efficacy of vatiquinone in vitro was assessed using human fibroblasts treated with the general mitochondrial oxidative stress inducer paraquat, the GPX4 inhibitor RSL3, or the glutathione synthase inhibitor BSO in combination with excess iron. The therapeutic potential of vatiquinone in vivo was assessed using tamoxifen-induced mouse model for GPX4 deficiency and the Ndufs4 knockout mouse model of Leigh syndrome. In both models, animals were treated daily with vatiquinone or vehicle and relevant disease endpoints were assessed. Results: Vatiquinone robustly prevented death in cultured cells induced by RSL3 or BSO/iron, but had no effect on paraquat induced cell death. Vatiquinone had no impact on disease onset, progression, or survival in either the tamoxifen-inducible GPX4 deficient model or the Ndufs4(-/-) mouse model, though the drug may have reduced seizure risk. Conclusions: Vatiquinone provided no benefit to survival in two mouse models of disease, but may prevent seizures in the Ndufs4(-/-) model. Our findings are consistent with recent press statements regarding clinical trial results and have implications for drug trial design and reporting in patients with rare diseases.

17.
Cell Res ; 34(8): 556-571, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38849501

RESUMEN

Physiologically, the atria contract first, followed by the ventricles, which is the prerequisite for normal blood circulation. The above phenomenon of atrioventricular sequential contraction results from the characteristically slow conduction of electrical excitation of the atrioventricular node (AVN) between the atria and the ventricles. However, it is not clear what controls the conduction of electrical excitation within AVNs. Here, we find that AVN pacemaker cells (AVNPCs) possess an intact intrinsic GABAergic system, which plays a key role in electrical conduction from the atria to the ventricles. First, along with the discovery of abundant GABA-containing vesicles under the surface membranes of AVNPCs, key elements of the GABAergic system, including GABA metabolic enzymes, GABA receptors, and GABA transporters, were identified in AVNPCs. Second, GABA synchronously elicited GABA-gated currents in AVNPCs, which significantly weakened the excitability of AVNPCs. Third, the key molecular elements of the GABAergic system markedly modulated the conductivity of electrical excitation in the AVN. Fourth, GABAA receptor deficiency in AVNPCs accelerated atrioventricular conduction, which impaired the AVN's protective potential against rapid ventricular frequency responses, increased susceptibility to lethal ventricular arrhythmias, and decreased the cardiac contractile function. Finally, interventions targeting the GABAergic system effectively prevented the occurrence and development of atrioventricular block. In summary, the endogenous GABAergic system in AVNPCs determines the slow conduction of electrical excitation within AVNs, thereby ensuring sequential atrioventricular contraction. The endogenous GABAergic system shows promise as a novel intervention target for cardiac arrhythmias.


Asunto(s)
Nodo Atrioventricular , Atrios Cardíacos , Ventrículos Cardíacos , Receptores de GABA-A , Ácido gamma-Aminobutírico , Animales , Ácido gamma-Aminobutírico/metabolismo , Ventrículos Cardíacos/metabolismo , Ventrículos Cardíacos/citología , Atrios Cardíacos/metabolismo , Atrios Cardíacos/citología , Nodo Atrioventricular/metabolismo , Nodo Atrioventricular/fisiología , Ratones , Receptores de GABA-A/metabolismo , Ratones Endogámicos C57BL , Masculino , Potenciales de Acción , Arritmias Cardíacas/metabolismo
18.
J Agric Food Chem ; 72(25): 14191-14198, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38878091

RESUMEN

3-Fucosyllactose (3-FL), an important fucosylated human milk oligosaccharide in breast milk, offers numerous health benefits to infants. Previously, we metabolically engineered Escherichia coli BL21(DE3) for the in vivo biosynthesis of 3-FL. In this study, we initially optimized culture conditions to double 3-FL production. Competing pathway genes involved in in vivo guanosine 5'-diphosphate-fucose biosynthesis were subsequently inactivated to redirect fluxes toward 3-FL biosynthesis. Next, three promising transporters were evaluated using plasmid-based or chromosomally integrated expression to maximize extracellular 3-FL production. Additionally, through analysis of α1,3-fucosyltransferase (FutM2) structure, we identified Q126 residues as a highly mutable residue in the active site. After site-saturation mutation, the best-performing mutant, FutM2-Q126A, was obtained. Structural analysis and molecular dynamics simulations revealed that small residue replacement positively influenced helical structure generation. Finally, the best strain BD3-A produced 6.91 and 52.1 g/L of 3-FL in a shake-flask and fed-batch cultivations, respectively, highlighting its potential for large-scale industrial applications.


Asunto(s)
Escherichia coli , Fucosiltransferasas , Ingeniería Metabólica , Trisacáridos , Escherichia coli/genética , Escherichia coli/metabolismo , Trisacáridos/metabolismo , Trisacáridos/biosíntesis , Trisacáridos/química , Fucosiltransferasas/genética , Fucosiltransferasas/metabolismo , Humanos , Oligosacáridos
19.
Adv Healthc Mater ; : e2400780, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850154

RESUMEN

Cell encapsulation technology, crucial for advanced biomedical applications, faces challenges in existing microfluidic and electrospray methods. Microfluidic techniques, while precise, can damage vulnerable cells, and conventional electrospray methods often encounter instability and capsule breakage during high-throughput encapsulation. Inspired by the transformation of the working state from unstable dripping to stable jetting triggered by local electric potential, this study introduces a superimposed electric field (SEF)-enhanced electrospray method for cell encapsulation, with improved stability and biocompatibility. Utilizing stiffness theory, the stability of the electrospray, whose stiffness is five times stronger under conical confinement, is quantitatively analyzed. The SEF technique enables rapid, continuous production of ≈300 core-shell capsules per second in an aqueous environment, significantly improving cell encapsulation efficiency. This method demonstrates remarkable potential as exemplified in two key applications: (1) a 92-fold increase in human-derived induced pluripotent stem cells (iPSCs) expansion over 10 d, outperforming traditional 2D cultures in both growth rate and pluripotency maintenance, and (2) the development of liver capsules for steatosis modeling, exhibiting normal function and biomimetic lipid accumulation. The SEF-enhanced electrospray method presents a significant advancement in cell encapsulation technology. It offers a more efficient, stable, and biocompatible approach for clinical transplantation, drug screening, and cell therapy.

20.
J Craniofac Surg ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738898

RESUMEN

OBJECTIVES: This prospective cohort study aimed to describe the technique of mini endoscopic septoplasty for patients with a high localized nasal septum deviation in front of the middle turbinate and chronic sinusitis or nasal sinus fungus ball. Our primary objective was to investigate the indications and outcomes of this procedure, and the secondary objective was to compare it with regular endoscopic septoplasty. METHODS: Patients with chronic sinusitis or nasal sinus fungus ball and high localized nasal septum deviation underwent mini endoscopic septoplasty, while those with a broad deviation of the nasal septum underwent regular endoscopic septoplasty. The study evaluated the procedure duration, blood loss, and complications associated with both methods. All patients were followed up for 3 months. RESULTS: Thirty patients underwent mini endoscopic septoplasty; another 30 underwent regular endoscopic septoplasty. Mini endoscopic septoplasty demonstrated a significantly shorter procedure duration and lower blood loss than regular endoscopic septoplasty. Neither group experienced operative complications, such as nasal septum perforation or hematoma. CONCLUSION: Mini endoscopic septoplasty is a safe, time-efficient, and effective technique indicated for highly localized nasal septum deviations in patients with chronic sinusitis or nasal sinus fungus ball. This procedure offers advantages in terms of the surgical approach and postoperative debridement. Future research could explore the broader clinical implications of these findings.

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