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1.
Nat Immunol ; 25(8): 1422-1431, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38961274

RESUMEN

The differentiation of naive and memory B cells into antibody-secreting cells (ASCs) is a key feature of adaptive immunity. The requirement for phosphoinositide 3-kinase-delta (PI3Kδ) to support B cell biology has been investigated intensively; however, specific functions of the related phosphoinositide 3-kinase-gamma (PI3Kγ) complex in B lineage cells have not. In the present study, we report that PI3Kγ promotes robust antibody responses induced by T cell-dependent antigens. The inborn error of immunity caused by human deficiency in PI3Kγ results in broad humoral defects, prompting our investigation of roles for this kinase in antibody responses. Using mouse immunization models, we found that PI3Kγ functions cell intrinsically within activated B cells in a kinase activity-dependent manner to transduce signals required for the transcriptional program supporting differentiation of ASCs. Furthermore, ASC fate choice coincides with upregulation of PIK3CG expression and is impaired in the context of PI3Kγ disruption in naive B cells on in vitro CD40-/cytokine-driven activation, in memory B cells on toll-like receptor activation, or in human tonsillar organoids. Taken together, our study uncovers a fundamental role for PI3Kγ in supporting humoral immunity by integrating signals instructing commitment to the ASC fate.


Asunto(s)
Formación de Anticuerpos , Linfocitos B , Diferenciación Celular , Fosfatidilinositol 3-Quinasa Clase Ib , Animales , Fosfatidilinositol 3-Quinasa Clase Ib/metabolismo , Fosfatidilinositol 3-Quinasa Clase Ib/inmunología , Ratones , Diferenciación Celular/inmunología , Humanos , Linfocitos B/inmunología , Linfocitos B/metabolismo , Formación de Anticuerpos/inmunología , Ratones Noqueados , Células Productoras de Anticuerpos/inmunología , Activación de Linfocitos/inmunología , Ratones Endogámicos C57BL , Transducción de Señal/inmunología , Células B de Memoria/inmunología , Células B de Memoria/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(1): e2213537120, 2023 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-36574707

RESUMEN

Dose-limiting cardiotoxicity remains a major limitation in the clinical use of cancer chemotherapeutics. Here, we describe a role for Regulator of G protein Signaling 7 (RGS7) in chemotherapy-dependent heart damage, the demonstration for a functional role of RGS7 outside of the nervous system and retina. Though expressed at low levels basally, we observed robust up-regulation of RGS7 in the human and murine myocardium following chemotherapy exposure. In ventricular cardiomyocytes (VCM), RGS7 forms a complex with Ca2+/calmodulin-dependent protein kinase (CaMKII) supported by key residues (K412 and P391) in the RGS domain of RGS7. In VCM treated with chemotherapeutic drugs, RGS7 facilitates CaMKII oxidation and phosphorylation and CaMKII-dependent oxidative stress, mitochondrial dysfunction, and apoptosis. Cardiac-specific RGS7 knockdown protected the heart against chemotherapy-dependent oxidative stress, fibrosis, and myocyte loss and improved left ventricular function in mice treated with doxorubicin. Conversely, RGS7 overexpression induced fibrosis, reactive oxygen species generation, and cell death in the murine myocardium that were mitigated following CaMKII inhibition. RGS7 also drives production and release of the cardiokine neuregulin-1, which facilitates paracrine communication between VCM and neighboring vascular endothelial cells (EC), a maladaptive mechanism contributing to VCM dysfunction in the failing heart. Importantly, while RGS7 was both necessary and sufficient to facilitate chemotherapy-dependent cytotoxicity in VCM, RGS7 is dispensable for the cancer-killing actions of these same drugs. These selective myocyte-intrinsic and myocyte-extrinsic actions of RGS7 in heart identify RGS7 as an attractive therapeutic target in the mitigation of chemotherapy-driven cardiotoxicity.


Asunto(s)
Antineoplásicos , Cardiotoxicidad , Proteínas RGS , Animales , Humanos , Ratones , Antineoplásicos/efectos adversos , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Cardiotoxicidad/metabolismo , Células Endoteliales/metabolismo , Fibrosis , Miocitos Cardíacos/metabolismo , Proteínas RGS/genética , Proteínas RGS/metabolismo
3.
J Clin Immunol ; 44(2): 44, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38231408

RESUMEN

Defining monogenic drivers of autoinflammatory syndromes elucidates mechanisms of disease in patients with these inborn errors of immunity and can facilitate targeted therapeutic interventions. Here, we describe a cohort of patients with a Behçet's- and inflammatory bowel disease (IBD)-like disorder termed "deficiency in ELF4, X-linked" (DEX) affecting males with loss-of-function variants in the ELF4 transcription factor gene located on the X chromosome. An international cohort of fourteen DEX patients was assessed to identify unifying clinical manifestations and diagnostic criteria as well as collate findings informing therapeutic responses. DEX patients exhibit a heterogeneous clinical phenotype including weight loss, oral and gastrointestinal aphthous ulcers, fevers, skin inflammation, gastrointestinal symptoms, arthritis, arthralgia, and myalgia, with findings of increased inflammatory markers, anemia, neutrophilic leukocytosis, thrombocytosis, intermittently low natural killer and class-switched memory B cells, and increased inflammatory cytokines in the serum. Patients have been predominantly treated with anti-inflammatory agents, with the majority of DEX patients treated with biologics targeting TNFα.


Asunto(s)
Artritis , Síndrome de Behçet , Productos Biológicos , Enfermedades Inflamatorias del Intestino , Masculino , Humanos , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/genética , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/genética , Artralgia , Proteínas de Unión al ADN , Factores de Transcripción/genética
4.
BMC Plant Biol ; 24(1): 676, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39009989

RESUMEN

Tilletia indica Mitra causes Karnal bunt (KB) in wheat by pathogenic dikaryophase. The present study is the first to provide the draft genomes of the dikaryon (PSWKBGD-3) and its two monosporidial lines (PSWKBGH-1 and 2) using Illumina and PacBio reads, their annotation and the comparative analyses among the three genomes by extracting polymorphic SSR markers. The trancriptome from infected wheat grains of the susceptible wheat cultivar WL711 at 24 h, 48h, and 7d after inoculation of PSWKBGH-1, 2 and PSWKBGD-3 were also isolated. Further, two transcriptome analyses were performed utilizing T. indica transcriptome to extract dikaryon genes responsible for pathogenesis, and wheat transcriptome to extract wheat genes affected by dikaryon involved in plant-pathogen interaction during progression of KB in wheat. A total of 54, 529, and 87 genes at 24hai, 48hai, and 7dai, respectively were upregulated in dikaryon stage while 21, 35, and 134 genes of T. indica at 24hai, 48hai, and 7dai, respectively, were activated only in dikaryon stage. While, a total of 23, 17, and 52 wheat genes at 24hai, 48hai, and 7dai, respectively were upregulated due to the presence of dikaryon stage only. The results obtained during this study have been compiled in a web resource called TiGeR ( http://backlin.cabgrid.res.in/tiger/ ), which is the first genomic resource for T. indica cataloguing genes, genomic and polymorphic SSRs of the three T. indica lines, wheat and T. indica DEGs as well as wheat genes affected by T. indica dikaryon along with the pathogenecity related proteins of T. indica dikaryon during incidence of KB at different time points. The present study would be helpful to understand the role of dikaryon in plant-pathogen interaction during progression of KB, which would be helpful to manage KB in wheat, and to develop KB-resistant wheat varieties.


Asunto(s)
Basidiomycota , Enfermedades de las Plantas , Transcriptoma , Triticum , Triticum/genética , Triticum/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Basidiomycota/patogenicidad , Basidiomycota/fisiología , Perfilación de la Expresión Génica , Genoma Fúngico , Interacciones Huésped-Patógeno/genética
5.
Chembiochem ; 25(11): e202400045, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38593270

RESUMEN

SUMO (Small Ubiquitin-like Modifiers) proteins are involved in a crucial post-translational modification commonly termed as SUMOylation. In this work, we have investigated the native-state conformational flexibility of human SUMO2 and its interaction with Cu2+ and Zn2+ ions using 15N-1H based 2D NMR spectroscopy. After SUMO1, SUMO2 is the most studied SUMO isoform in humans which shares 45 % and ~80 % similarity with SUMO1 in terms of sequence and structure, respectively. In this manuscript, we demonstrate that compared to SUMO1, several amino acids around the α1-helix region of SUMO2 access energetically similar near-native conformations. These conformations could play a crucial role in SUMO2's non-covalent interactions with SUMO interaction motifs (SIMs) on other proteins. The C-terminal of SUMO2 was found to bind strongly with Cu2+ ions resulting in a trimeric structure as observed by gel electrophoresis. This interaction seems to interfere in its non-covalent interaction with a V/I-x-V/I-V/I based SIM in Daxx protein.


Asunto(s)
Cobre , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina , Zinc , Humanos , Cobre/química , Cobre/metabolismo , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/metabolismo , Proteínas Modificadoras Pequeñas Relacionadas con Ubiquitina/química , Zinc/química , Zinc/metabolismo , Conformación Proteica , Resonancia Magnética Nuclear Biomolecular , Unión Proteica
6.
J Synchrotron Radiat ; 31(Pt 1): 85-94, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37947305

RESUMEN

X-ray-based computed tomography is a well established technique for determining the three-dimensional structure of an object from its two-dimensional projections. In the past few decades, there have been significant advancements in the brightness and detector technology of tomography instruments at synchrotron sources. These advancements have led to the emergence of new observations and discoveries, with improved capabilities such as faster frame rates, larger fields of view, higher resolution and higher dimensionality. These advancements have enabled the material science community to expand the scope of tomographic measurements towards increasingly in situ and in operando measurements. In these new experiments, samples can be rapidly evolving, have complex geometries and restrictions on the field of view, limiting the number of projections that can be collected. In such cases, standard filtered back-projection often results in poor quality reconstructions. Iterative reconstruction algorithms, such as model-based iterative reconstructions (MBIR), have demonstrated considerable success in producing high-quality reconstructions under such restrictions, but typically require high-performance computing resources with hundreds of compute nodes to solve the problem in a reasonable time. Here, tomoCAM, is introduced, a new GPU-accelerated implementation of model-based iterative reconstruction that leverages non-uniform fast Fourier transforms to efficiently compute Radon and back-projection operators and asynchronous memory transfers to maximize the throughput to the GPU memory. The resulting code is significantly faster than traditional MBIR codes and delivers the reconstructive improvement offered by MBIR with affordable computing time and resources. tomoCAM has a Python front-end, allowing access from Jupyter-based frameworks, providing straightforward integration into existing workflows at synchrotron facilities.

7.
J Transl Med ; 22(1): 204, 2024 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-38409136

RESUMEN

BACKGROUND: Prior evidence demonstrated that Regulator of G protein Signaling 6 (RGS6) translocates to the nucleolus in response to cytotoxic stress though the functional significance of this phenomenon remains unknown. METHODS: Utilizing in vivo gene manipulations in mice, primary murine cardiac cells, human cell lines and human patient samples we dissect the participation of a RGS6-nucleolin complex in chemotherapy-dependent cardiotoxicity. RESULTS: Here we demonstrate that RGS6 binds to a key nucleolar protein, Nucleolin, and controls its expression and activity in cardiomyocytes. In the human myocyte AC-16 cell line, induced pluripotent stem cell derived cardiomyocytes, primary murine cardiomyocytes, and the intact murine myocardium tuning RGS6 levels via overexpression or knockdown resulted in diametrically opposed impacts on Nucleolin mRNA, protein, and phosphorylation.RGS6 depletion provided marked protection against nucleolar stress-mediated cell death in vitro, and, conversely, RGS6 overexpression suppressed ribosomal RNA production, a key output of the nucleolus, and triggered death of myocytes. Importantly, overexpression of either Nucleolin or Nucleolin effector miRNA-21 counteracted the pro-apoptotic effects of RGS6. In both human and murine heart tissue, exposure to the genotoxic stressor doxorubicin was associated with an increase in the ratio of RGS6/Nucleolin. Preventing RGS6 induction via introduction of RGS6-directed shRNA via intracardiac injection proved cardioprotective in mice and was accompanied by restored Nucleolin/miRNA-21 expression, decreased nucleolar stress, and decreased expression of pro-apoptotic, hypertrophy, and oxidative stress markers in heart. CONCLUSION: Together, these data implicate RGS6 as a driver of nucleolar stress-dependent cell death in cardiomyocytes via its ability to modulate Nucleolin. This work represents the first demonstration of a functional role for an RGS protein in the nucleolus and identifies the RGS6/Nucleolin interaction as a possible new therapeutic target in the prevention of cardiotoxicity.


Asunto(s)
MicroARNs , Proteínas RGS , Animales , Humanos , Ratones , Cardiotoxicidad , MicroARNs/genética , Miocitos Cardíacos , Nucleolina , Proteínas RGS/genética , Transducción de Señal/fisiología
8.
Blood ; 140(13): 1496-1506, 2022 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-35793467

RESUMEN

Somatic mutations in UBA1 cause vacuoles, E1 ubiquitin-activating enzyme, X-linked, autoinflammatory somatic (VEXAS) syndrome, an adult-onset inflammatory disease with an overlap of hematologic manifestations. VEXAS syndrome is characterized by a high mortality rate and significant clinical heterogeneity. We sought to determine independent predictors of survival in VEXAS and to understand the mechanistic basis for these factors. We analyzed 83 patients with somatic pathogenic variants in UBA1 at p.Met41 (p.Met41Leu/Thr/Val), the start codon for translation of the cytoplasmic isoform of UBA1 (UBA1b). Patients with the p.Met41Val genotype were most likely to have an undifferentiated inflammatory syndrome. Multivariate analysis showed ear chondritis was associated with increased survival, whereas transfusion dependence and the p.Met41Val variant were independently associated with decreased survival. Using in vitro models and patient-derived cells, we demonstrate that p.Met41Val variant supports less UBA1b translation than either p.Met41Leu or p.Met41Thr, providing a molecular rationale for decreased survival. In addition, we show that these 3 canonical VEXAS variants produce more UBA1b than any of the 6 other possible single-nucleotide variants within this codon. Finally, we report a patient, clinically diagnosed with VEXAS syndrome, with 2 novel mutations in UBA1 occurring in cis on the same allele. One mutation (c.121 A>T; p.Met41Leu) caused severely reduced translation of UBA1b in a reporter assay, but coexpression with the second mutation (c.119 G>C; p.Gly40Ala) rescued UBA1b levels to those of canonical mutations. We conclude that regulation of residual UBA1b translation is fundamental to the pathogenesis of VEXAS syndrome and contributes to disease prognosis.


Asunto(s)
Nucleótidos , Enzimas Activadoras de Ubiquitina , Codón Iniciador , Humanos , Mutación , Enzimas Activadoras de Ubiquitina/genética , Ubiquitinación
9.
Mol Pharm ; 21(6): 3061-3076, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38757678

RESUMEN

Melanoma, characterized as the most aggressive and metastatic form of skin cancer, currently has limited treatment options, predominantly chemotherapy and radiation therapy. However, the drawbacks associated with parenterally administered chemotherapy underscore the urgent need for alternative compounds to combat melanoma effectively. Hesperidin (HES), a flavonoid present in various citrus fruits, exhibits promising anticancer activity. Nevertheless, the clinical utility of HES is hindered by challenges such as poor water solubility, a short half-life, and low oral bioavailability. In response to these limitations, we introduced a novel approach by formulating HES-loaded exosomes (Exo-HES). Isolation of exosomes was achieved through the ultracentrifugation method, and HES was efficiently loaded using the sonication method. The resulting formulations displayed a desirable particle size (∼106 nm) and exhibited a spherical morphology, as confirmed by scanning electron and atomic force microscopy. In vitro studies conducted on B16F10 cell lines demonstrated higher cytotoxicity of Exo-HES compared to free HES, supported by enhanced cellular uptake validated through coumarin-6-loaded exosomes. This superior cytotoxicity was further evidenced by DNA fragmentation, increased generation of free radicals (ROS), loss of mitochondrial membrane potential, and effective inhibition of colony formation. The antimetastatic properties of Exo-HES were confirmed through wound healing and transwell migration assays. Oral pharmacokinetics studies revealed a remarkable increase of approximately 2.5 times in oral bioavailability and half-life of HES when loaded into exosomes. Subsequent in vivo experiments utilizing a B16F10-induced melanoma model in Swiss mice established that Exo-HES exhibited superior anticancer activity compared to HES after oral administration. Importantly, no biochemical, hematological, or histological toxicities were observed in tumor-bearing mice treated with Exo-HES. These findings suggest that exosomes loaded with HES represent a promising nanocarrier strategy to enhance the therapeutic effectiveness of hesperidin in melanoma treatment.


Asunto(s)
Exosomas , Hesperidina , Hesperidina/química , Hesperidina/farmacología , Hesperidina/administración & dosificación , Hesperidina/farmacocinética , Animales , Ratones , Línea Celular Tumoral , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/patología , Melanoma/tratamiento farmacológico , Melanoma/patología , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Masculino , Ratones Endogámicos C57BL , Sistemas de Liberación de Medicamentos/métodos
10.
Arch Microbiol ; 206(6): 272, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38772980

RESUMEN

Phage-encoded endolysins have emerged as a potential substitute to conventional antibiotics due to their exceptional benefits including host specificity, rapid host killing, least risk of resistance. In addition to their antibacterial potency and biofilm eradication properties, endolysins are reported to exhibit synergism with other antimicrobial agents. In this study, the synergistic potency of endolysins was dissected with antimicrobial peptides to enhance their therapeutic effectiveness. Recombinantly expressed and purified bacteriophage endolysin [T7 endolysin (T7L); and T4 endolysin (T4L)] proteins have been used to evaluate the broad-spectrum antibacterial efficacy using different bacterial strains. Antibacterial/biofilm eradication studies were performed in combination with different antimicrobial peptides (AMPs) such as colistin, nisin, and polymyxin B (PMB) to assess the endolysin's antimicrobial efficacy and their synergy with AMPs. In combination with T7L, polymyxin B and colistin effectively eradicated the biofilm of Pseudomonas aeruginosa and exhibited a synergistic effect. Further, a combination of T4L and nisin displayed a synergistic effect against Staphylococcus aureus biofilms. In summary, the obtained results endorse the theme of combinational therapy consisting of endolysins and AMPs as an effective remedy against the drug-resistant bacterial biofilms that are a serious concern in healthcare settings.


Asunto(s)
Antibacterianos , Péptidos Antimicrobianos , Biopelículas , Sinergismo Farmacológico , Endopeptidasas , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa , Staphylococcus aureus , Biopelículas/efectos de los fármacos , Endopeptidasas/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología , Pseudomonas aeruginosa/efectos de los fármacos , Péptidos Antimicrobianos/farmacología , Péptidos Antimicrobianos/química , Nisina/farmacología , Nisina/química , Polimixina B/farmacología , Bacteriófagos , Colistina/farmacología , Bacteriófago T4/efectos de los fármacos , Bacteriófago T4/fisiología , Bacteriófago T7/efectos de los fármacos , Bacteriófago T7/genética
11.
Langmuir ; 40(29): 15281-15292, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38989856

RESUMEN

An ensemble of nanosystems can be considered to improve magnetic resonance imaging (MRI) transverse relaxivity. Herein, an interacting superparamagnetic competing structure of an isotropic-anisotropic trimagnetic hybrid nanosystem, γ-Fe2O3@δ-MnO2@NiFe2O4, is considered for MRI relaxivity exploration. The interacting superparamagnetic system reveals fascinating dynamic magnetic behavior, where flower-shaped two-dimensional flakes are decorated over nanoparticles. The hybrid nanosystem exhibits modulated shape anisotropy with spin blocking and energy barrier broadening, which help in achieving faster MR transverse relaxivity. The hierarchical architecture ensemble of the trimagnetic landscape shows effective MR transverse relaxivity with a transverse (r2)/longitudinal (r1) relaxivity of 61.5 and potential cell viability. The competing trimagnetic system with regulated activation energy is found to be the underlying reason for such signal enhancement in MRI contrast efficiency. Hence, this study displays a novel pathway correlating MR transverse relaxivity with dynamic magnetic behavior and competing landscape of hierarchical trimagnetic ensembles.

12.
Langmuir ; 40(3): 1793-1803, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38181379

RESUMEN

The potential application of magnetic nanosystems as magnetic resonance imaging (MRI) contrast agents has been thoroughly investigated. This work seeks to attain robust MRI-contrast efficiency by designing an interacting landscape of a bimagnetic ensemble of zinc ferrite nanorods and maghemite nanoparticles, γ-Fe2O3@ZnFe2O4. Because of competing spin clusters and structural anisotropy triggered by isotropic γ-Fe2O3 and anisotropic ZnFe2O4, γ-Fe2O3@ZnFe2O4 undergoes the evolution of cluster spin-glass state as evident from the critical slowing down law. Such interacting γ-Fe2O3@ZnFe2O4 with spin flipping of 1.2 × 10-8 s and energy barrier of 8.2 × 10-14 erg reflects enhanced MRI-contrast signal. Additionally, γ-Fe2O3@ZnFe2O4 is cell-viable to noncancerous HEK 293 cell-line and shows no pro-tumorigenic activity as observed in MDA-MB-231, an extremely aggressive triple-negative breast cancer cell line. As a result, γ-Fe2O3@ZnFe2O4 is a feasible option for an MRI-contrast agent having longitudinal relaxivity, r1, of 0.46 s-1mM-1 and transverse relaxivity, r2, of 15.94 s-1mM-1, together with r2/r1 of 34.65 at 1.41 T up to a modest metal concentration of 0.1 mM. Hence, this study addresses an interacting isotropic/anisotropic framework with faster water proton decay in MR-relaxivity resulting in phantom signal amplification.

13.
Eur Biophys J ; 53(4): 193-203, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38647543

RESUMEN

Na+/H+ antiporters facilitate the exchange of Na+ for H+ across the cytoplasmic membrane in prokaryotic and eukaryotic cells. These transporters are crucial to maintain the homeostasis of sodium ions, consequently pH, and volume of the cells. Therefore, sodium/proton antiporters are considered promising therapeutic targets in humans. The Na+/H+ antiporter in Escherichia coli (Ec-NhaA), a prototype of cation-proton antiporter (CPA) family, transports two protons and one sodium (or Li+) in opposite direction. Previous mutagenesis experiments on Ec-NhaA have proposed Asp164, Asp163, and Asp133 amino acids with the significant implication in functional and structural integrity and create site for ion-binding. However, the mechanism and the sites for the binding of the two protons remain unknown and controversial which could be critical for pH regulation. In this study, we have explored the role of Glu78 in the regulation of pH by Ec-NhaA. Although we have created various mutants, E78C has shown a considerable effect on the stoichiometry of NhaA and presented comparable phenotypes. The ITC experiment has shown the binding of ~ 5 protons in response to the transport of one lithium ion. The phenotype analysis on selective medium showed a significant expression compared to WT Ec-NhaA. This represents the importance of Glu78 in transporting the H+ across the membrane where a single mutation with Cys amino acid alters the number of H+ significantly maintaining the activity of the protein.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Ácido Glutámico , Mutagénesis Sitio-Dirigida , Intercambiadores de Sodio-Hidrógeno , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Ácido Glutámico/metabolismo , Ácido Glutámico/química , Intercambiadores de Sodio-Hidrógeno/genética , Intercambiadores de Sodio-Hidrógeno/química , Intercambiadores de Sodio-Hidrógeno/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Intercambio Iónico , Modelos Moleculares
14.
Soft Matter ; 20(23): 4524-4543, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38738579

RESUMEN

The goal of this review is to present enzymosomes as an innovative means for site-specific drug delivery. Enzymosomes make use of an enzyme's special characteristics, such as its capacity to accelerate the reaction rate and bind to a particular substrate at a regulated rate. Enzymosomes are created when an enzyme forms a covalent linkage with a liposome or lipid vesicle surface. To construct enzymosomes with specialized activities, enzymes are linked using acylation, direct conjugation, physical adsorption, and encapsulation techniques. By reducing the negative side effects of earlier treatment techniques and exhibiting efficient medication release, these cutting-edge drug delivery systems improve long-term sickness treatments. They could be a good substitute for antiplatelet medication, gout treatment, and other traditional medicines. Recently developed supramolecular vesicular delivery systems called enzymosomes have the potential to improve drug targeting, physicochemical characteristics, and ultimately bioavailability in the pharmaceutical industry. Enzymosomes have advantages over narrow-therapeutic index pharmaceuticals as focusing on their site of action enhances both their pharmacodynamic and pharmacokinetic profiles. Additionally, it reduces changes in normal enzymatic activity, which enhances the half-life of an enzyme and accomplishes enzyme activity on specific locations.


Asunto(s)
Sistemas de Liberación de Medicamentos , Enzimas , Liposomas , Humanos , Liposomas/química , Enzimas/química , Enzimas/metabolismo , Animales
15.
Microb Cell Fact ; 23(1): 226, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39127680

RESUMEN

BACKGROUND: Endophytic fungi (EF) reside within plants without causing harm and provide benefits such as enhancing nutrients and producing bioactive compounds, which improve the medicinal properties of host plants. Selecting plants with established medicinal properties for studying EF is important, as it allows a deeper understanding of their influence. Therefore, the study aimed to investigate the impact of EF after inoculating the medicinal plant Perilla frutescens, specifically focusing on their role in enhancing medicinal properties. RESULTS: In the current study, the impact of two EF i.e., Irpex lenis and Schizophyllum commune isolated from A. bracteosa was observed on plant Perilla frutescens leaves after inoculation. Plants were divided into four groups i.e., group A: the control group, group B: inoculated with I. lenis; group C: inoculated with S. commune and group D: inoculated with both the EF. Inoculation impact of I. lenis showed an increase in the concentration of chlorophyll a (5.32 mg/g), chlorophyll b (4.46 mg/g), total chlorophyll content (9.78 mg/g), protein (68.517 ± 0.77 mg/g), carbohydrates (137.886 ± 13.71 mg/g), and crude fiber (3.333 ± 0.37%). Furthermore, the plants inoculated with I. lenis showed the highest concentrations of P (14605 mg/kg), Mg (4964.320 mg/kg), Ca (27389.400 mg/kg), and Mn (86.883 mg/kg). The results of the phytochemical analysis also indicated an increased content of total flavonoids (2.347 mg/g), phenols (3.086 mg/g), tannins (3.902 mg/g), and alkaloids (1.037 mg/g) in the leaf extract of P. frutescens inoculated with I. lenis. Thus, overall the best results of inoculation were observed in Group B i.e. inoculated with I. lenis. GC-MS analysis of methanol leaf extract showed ten bioactive constituents, including 9-Octadecenoic acid (Z)-, methyl ester, and hexadecanoic acid, methyl ester as major constituents found in all the groups of P. frutescens leaves. The phenol (gallic acid) and flavonoids (rutin, kaempferol, and quercetin) were also observed to increase after inoculation by HPTLC analysis. The enhancement in the phytochemical content was co-related with improved anti-oxidant potential which was analyzed by DPPH (% Inhibition: 83.45 µg/ml) and FRAP (2.980 µM Fe (II) equivalent) assay as compared with the control group. CONCLUSION: Inoculation with I. lenis significantly enhances the uptake of nutritional constituents, phytochemicals, and antioxidant properties in P. frutescens, suggesting its potential to boost the therapeutic properties of host plants.


Asunto(s)
Antioxidantes , Endófitos , Perilla frutescens , Fitoquímicos , Hojas de la Planta , Schizophyllum , Perilla frutescens/química , Perilla frutescens/metabolismo , Antioxidantes/metabolismo , Schizophyllum/metabolismo , Fitoquímicos/química , Fitoquímicos/metabolismo , Fitoquímicos/farmacología , Endófitos/metabolismo , Hojas de la Planta/microbiología , Hojas de la Planta/química , Clorofila/metabolismo
16.
J Fluoresc ; 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38457073

RESUMEN

Extensive investigations were conducted on the structural and photoluminescence characteristics of the present nanosamples, encompassing PL, TEM, PXRD, EDAX, CCT, and CIE research. PXRD studies established a single phase, and TEM instruments were used to examine the dimensions and topographical behavior. The EDAX analysis examined the magnitude of the different components that were present. Decay lifetimes, radiative and non-radiative energy transfer rates, and a number of intensity limitations have all been found using PL spectra. Two significant peaks were visible in the blue (B) and yellow (Y) regions of the photoluminescence (PL) spectra upon NUV excitation, at 486 nm and 577 nm. At 7 mol% Dy3+ ions, the PL intensity peaked. After that, it began to decline as a result of the concentration quenching process brought on by multipolar exchanges (s = 4.1445). The values of 0.86423 ms, 81%, and 226 s-1 were discovered to be the decay life time, non radiative rates, and quantum efficiency of the ideal powder, respectively. Further analysis of Sr3Y0.93Dy0.07(PO4)3 nanocrystals revealed that their chromaticity coordinates (0.305, 0.321), and CCT value (6902 K) matched those of NTSE and commercial LEDs, certifying their use in innovative optoelectronic appliances, particularly single phased WLEDs.

17.
J Fluoresc ; 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39153166

RESUMEN

Solution combustion procedure was used to create a succession of Na3LaxSm1 - x(PO4)2 (x = 0.01-0.15 mol) nanocrystals that generate a warm deep reddish light. Both HR-TEM and X-ray diffraction examinations were used to examine the morphology and crystalline phase analysis. Energy-dispersive X-ray analysis (EDAX) approves the elemental examination. The luminescence spectrum exhibits a decent reddish-orange emission at 700 nm wavelength upon near-UV illumination, which aligns with the electronic transition 4G5/2 → 6H11/2. According to Dexter's idea, nearest neighbor interlinkages are responsible for the concentration quenching that occurs after the Sm3+ ion composition reaches 6 mol%. Additionally, a detailed evaluation of the radiative lifespan (0.7519 ms), quantum efficiency (77%), Non radiative rate (307.40), color temperature (3170 K), color purity (99.2%) and color coordinates (0.652, 0.338) was conducted. The optical characteristics that have been observed indicate that Sm3+ doped Na3La(PO4)2 phosphors could be a good option for improving WLED efficiency and color quality.

18.
Cell Mol Life Sci ; 80(9): 255, 2023 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-37589751

RESUMEN

Cardiotoxicity remains a major limitation in the clinical utility of anthracycline chemotherapeutics. Regulator of G-protein Signaling 7 (RGS7) and inflammatory markers are up-regulated in the hearts of patients with a history of chemotherapy particularly those with reduced left-ventricular function. RGS7 knockdown in either the murine myocardium or isolated murine ventricular cardiac myocytes (VCM) or cultured human VCM provided marked protection against doxorubicin-dependent oxidative stress, NF-κB activation, inflammatory cytokine production, and cell death. In exploring possible mechanisms causally linking RGS7 to pro-inflammatory signaling cascades, we found that RGS7 forms a complex with acetylase Tip60 and deacetylase sirtuin 1 (SIRT1) and controls the acetylation status of the p65 subunit of NF-κB. In VCM, the detrimental impact of RGS7 could be mitigated by inhibiting Tip60 or activating SIRT1, indicating that the ability of RGS7 to modulate cellular acetylation capacity is critical for its pro-inflammatory actions. Further, RGS7-driven, Tip60/SIRT1-dependent cytokines released from ventricular cardiac myocytes and transplanted onto cardiac fibroblasts increased oxidative stress, markers of transdifferentiation, and activity of extracellular matrix remodelers emphasizing the importance of the RGS7-Tip60-SIRT1 complex in paracrine signaling in the myocardium. Importantly, while RGS7 overexpression in heart resulted in sterile inflammation, fibrotic remodeling, and compromised left-ventricular function, activation of SIRT1 counteracted the detrimental impact of RGS7 in heart confirming that RGS7 increases acetylation of SIRT1 substrates and thereby drives cardiac dysfunction. Together, our data identify RGS7 as an amplifier of inflammatory signaling in heart and possible therapeutic target in chemotherapeutic drug-induced cardiotoxicity.


Asunto(s)
Cardiotoxicidad , Proteínas RGS , Humanos , Animales , Ratones , Acetilación , FN-kappa B , Sirtuina 1/genética , Arritmias Cardíacas , Miocitos Cardíacos , Proteínas RGS/genética
19.
BMC Urol ; 24(1): 180, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39192248

RESUMEN

BACKGROUND: Male infertility due to spermatogenesis defects affects millions of men worldwide. However, the genetic etiology of the vast majority remains unclear. The present study was undertaken to assess the association of DNAH6 and ATPase6 genes in asthenozoospermia patients in the northern region of India. METHODS: A total of 60 semen samples were collected for the study, of which 30 were from the case group and 30 were from the control group. The semen samples for the case group (asthenozoospermia) and control groups were collected from IVF and Reproductive Biology Centre, Maulana Azad Medical College, New Delhi. Sperm count and motility were classified as per World Health Organization (WHO 2021) protocol. A total genomic DNA was extracted as per the stranded TRIZOL method with little modification. RESULTS: In-vitro molecular characterizations of DNAH6 and ATPase6 genes in both groups were checked by Polymerase Chain Reaction (PCR). The 675 bp and 375 bp amplicons were amplified using PCR for ATPase6 and DNAH6 genes. Our study results showed a significant (P ≤ 0.05) null deletion of DNAH6 and ATPase6 genes in asthenozoospermia patients as compared to the control. We found the significant null deletion of DNAH6 in case 45.0%, and the control group was 11.7%. However, in the case of APTase6, it was 26.7% and 10.0%, respectively. CONCLUSIONS: Our study concluded that the presence of DHAH6 and ATPase6 genes had a significant impact on male infertility.


Asunto(s)
Astenozoospermia , Humanos , Masculino , Astenozoospermia/genética , India , Adulto , ATPasas de Translocación de Protón Mitocondriales/genética , ADN Mitocondrial/genética
20.
Metab Brain Dis ; 39(2): 283-294, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38095788

RESUMEN

Brain stroke (BS, also known as a cerebrovascular accident), represents a serious global health crisis. It has been a leading cause of permanent disability and unfortunately, frequent fatalities due to lack of timely medical intervention. While progress has been made in prevention and management, the complexities and consequences of stroke continue to pose significant challenges, especially, its impact on patient's quality of life and independence. During stroke, there is a substantial decrease in oxygen supply to the brain leading to alteration of cellular metabolic pathways, including those involved in mitochondrial-damage, leading to mitochondrial-dysfunction. The present proof-of-the-concept metabolomics study has been performed to gain insights into the metabolic pathways altered following a brain stroke and discover new potential targets for timely interventions to mitigate the effects of cellular and mitochondrial damage in BS. The serum metabolic profiles of 108 BS-patients were measured using 800 MHz NMR spectroscopy and compared with 60 age and sex matched normal control (NC) subjects. Compared to NC, the serum levels of glutamate, TCA-cycle intermediates (such as citrate, succinate, etc.), and membrane metabolites (betaine, choline, etc.) were found to be decreased BS patients, whereas those of methionine, mannose, mannitol, phenylalanine, urea, creatine and organic acids (such as 3-hydroxybutyrate and acetone) were found to be elevated in BS patients. These metabolic changes hinted towards hypoxia mediated mitochondrial dysfunction in BS-patients. Further, the area under receiver operating characteristic curve (ROC) values for five metabolic features (methionine, mannitol, phenylalanine, mannose and urea) found to be more than 0.9 suggesting their high sensitivity and specificity for differentiating BS from NC subjects.


Asunto(s)
Manosa , Accidente Cerebrovascular , Humanos , Calidad de Vida , Metabolómica/métodos , Espectroscopía de Resonancia Magnética/métodos , Encéfalo/metabolismo , Estrés Oxidativo , Fenilalanina , Metionina , Manitol , Urea , Biomarcadores
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