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1.
Nature ; 606(7914): 550-556, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35545672

RESUMEN

Animals constantly receive various sensory stimuli, such as odours, sounds, light and touch, from the surrounding environment. These sensory inputs are essential for animals to search for food and avoid predators, but they also affect their physiological status, and may cause diseases such as cancer. Malignant gliomas-the most lethal form of brain tumour1-are known to intimately communicate with neurons at the cellular level2,3. However, it remains unclear whether external sensory stimuli can directly affect the development of malignant glioma under normal living conditions. Here we show that olfaction can directly regulate gliomagenesis. In an autochthonous mouse model that recapitulates adult gliomagenesis4-6 originating in oligodendrocyte precursor cells (OPCs), gliomas preferentially emerge in the olfactory bulb-the first relay of brain olfactory circuitry. Manipulating the activity of olfactory receptor neurons (ORNs) affects the development of glioma. Mechanistically, olfaction excites mitral and tufted (M/T) cells, which receive sensory information from ORNs and release insulin-like growth factor 1 (IGF1) in an activity-dependent manner. Specific knockout of Igf1 in M/T cells suppresses gliomagenesis. In addition, knocking out the IGF1 receptor in pre-cancerous mutant OPCs abolishes the ORN-activity-dependent mitogenic effects. Our findings establish a link between sensory experience and gliomagenesis through their corresponding sensory neuronal circuits.


Asunto(s)
Carcinogénesis , Glioma , Factor I del Crecimiento Similar a la Insulina , Neuronas Receptoras Olfatorias , Olfato , Animales , Glioma/metabolismo , Glioma/patología , Ratones , Vías Nerviosas , Bulbo Olfatorio/patología , Neuronas Receptoras Olfatorias/fisiología , Olfato/fisiología
2.
Nature ; 599(7884): 320-324, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34707294

RESUMEN

The Dispatched protein, which is related to the NPC1 and PTCH1 cholesterol transporters1,2 and to H+-driven transporters of the RND family3,4, enables tissue-patterning activity of the lipid-modified Hedgehog protein by releasing it from tightly -localized sites of embryonic expression5-10. Here we determine a cryo-electron microscopy structure of the mouse protein Dispatched homologue 1 (DISP1), revealing three Na+ ions coordinated within a channel that traverses its transmembrane domain. We find that the rate of Hedgehog export is dependent on the Na+ gradient across the plasma membrane. The transmembrane channel and Na+ binding are disrupted in DISP1-NNN, a variant with asparagine substitutions for three intramembrane aspartate residues that each coordinate and neutralize the charge of one of the three Na+ ions. DISP1-NNN and variants that disrupt single Na+ sites retain binding to, but are impaired in export of the lipid-modified Hedgehog protein to the SCUBE2 acceptor. Interaction of the amino-terminal signalling domain of the Sonic hedgehog protein (ShhN) with DISP1 occurs via an extensive buried surface area and contacts with an extended furin-cleaved DISP1 arm. Variability analysis reveals that ShhN binding is restricted to one extreme of a continuous series of DISP1 conformations. The bound and unbound DISP1 conformations display distinct Na+-site occupancies, which suggests a mechanism by which transmembrane Na+ flux may power extraction of the lipid-linked Hedgehog signal from the membrane. Na+-coordinating residues in DISP1 are conserved in PTCH1 and other metazoan RND family members, suggesting that Na+ flux powers their conformationally driven activities.


Asunto(s)
Microscopía por Crioelectrón , Proteínas Hedgehog/química , Proteínas Hedgehog/metabolismo , Metabolismo de los Lípidos , Proteínas de la Membrana/metabolismo , Sodio/metabolismo , Animales , Sitios de Unión , Membrana Celular/química , Membrana Celular/metabolismo , Proteínas Hedgehog/ultraestructura , Lípidos de la Membrana/química , Lípidos de la Membrana/aislamiento & purificación , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Proteínas de la Membrana/ultraestructura , Ratones , Modelos Moleculares , Mutación
3.
Plant Physiol ; 194(3): 1764-1778, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38035763

RESUMEN

Clubroot, caused by the soil-borne protist pathogen Plasmodiophora brassicae, is one of the most devastating diseases of Brassica oil and vegetable crops worldwide. Understanding the pathogen infection strategy is crucial for the development of disease control. However, because of its obligate biotrophic nature, the molecular mechanism by which this pathogen promotes infection remains largely unknown. P. brassicae E3 ubiquitin ligase 2 (PbE3-2) is a Really Interesting New Gene (RING)-type E3 ubiquitin ligase in P. brassicae with E3 ligase activity in vitro. Yeast (Saccharomyces cerevisiae) invertase assay and apoplast washing fluid extraction showed that PbE3-2 harbors a functional signal peptide. Overexpression of PbE3-2 in Arabidopsis (Arabidopsis thaliana) resulted in higher susceptibility to P. brassicae and decreases in chitin-triggered reactive oxygen species burst and expression of marker genes in salicylic acid signaling. PbE3-2 interacted with and ubiquitinated host cysteine protease RESPONSIVE TO DEHYDRATION 21A (RD21A) in vitro and in vivo. Mutant plants deficient in RD21A exhibited similar susceptibility and compromised immune responses as in PbE3-2 overexpression plants. We show that PbE3-2, which targets RD21A, is an important virulence factor for P. brassicae. Two other secretory RING-type E3 ubiquitin ligases in P. brassicae performed the same function as PbE3-2 and ubiquitinated RD21A. This study reveals a substantial virulence functional role of protist E3 ubiquitin ligases and demonstrates a mechanism by which protist E3 ubiquitin ligases degrade host immune-associated cysteine proteases to impede host immunity.


Asunto(s)
Arabidopsis , Proteasas de Cisteína , Arabidopsis/genética , Proteasas de Cisteína/genética , Inmunidad de la Planta/genética , Saccharomyces cerevisiae , Ubiquitina , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación
4.
Cereb Cortex ; 34(3)2024 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-38517175

RESUMEN

Intermittent theta-burst stimulation (iTBS) is emerging as a noninvasive therapeutic strategy for Alzheimer's disease (AD). Recent advances highlighted a new accelerated iTBS (aiTBS) protocol, consisting of multiple sessions per day and higher overall pulse doses, in brain modulation. To examine the possibility of applying the aiTBS in treating AD patients, we enrolled 45 patients in AD at early clinical stages, and they were randomly assigned to either receive real or sham aiTBS. Neuropsychological scores were evaluated before and after treatment. Moreover, we detected cortical excitability and oscillatory activity changes in AD, by the single-pulse TMS in combination with EEG (TMS-EEG). Real stimulation showed markedly better performances in the group average of Auditory Verbal Learning Test scores compared to baseline. TMS-EEG revealed that aiTBS has reinforced this memory-related cortical mechanism by increasing cortical excitability and beta oscillatory activity underlying TMS target. We also found an enhancement of local natural frequency after aiTBS treatment. The novel findings implicated that high-dose aiTBS targeting left DLPFC is rapid-acting, safe, and tolerable in AD patients. Furthermore, TMS-related increase of specific neural oscillation elucidates the mechanisms of the AD cognitive impairment ameliorated by aiTBS.


Asunto(s)
Enfermedad de Alzheimer , Estimulación Magnética Transcraneal , Humanos , Estimulación Magnética Transcraneal/métodos , Enfermedad de Alzheimer/terapia , Corteza Prefrontal/fisiología , Encéfalo , Corteza Prefontal Dorsolateral
5.
Mol Ther ; 32(3): 749-765, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38310356

RESUMEN

Approximately 80%-90% of hepatocellular carcinomas (HCC) occur in a premalignant environment of fibrosis and abnormal extracellular matrix (ECM), highlighting an essential role of ECM in the tumorigenesis and progress of HCC. However, the determinants of ECM in HCC are poorly defined. Here, we show that nuclear receptor RORγ is highly expressed and amplified in HCC tumors. RORγ functions as an essential activator of the matrisome program via directly driving the expression of major ECM genes in HCC cells. Elevated RORγ increases fibronectin-1 deposition, cell-matrix adhesion, and collagen production, creating a favorable microenvironment to boost liver cancer metastasis. Moreover, RORγ antagonists effectively inhibit tumor growth and metastasis in multiple HCC xenografts and immune-intact models, and they effectively sensitize HCC tumors to sorafenib therapy in mice. Notably, elevated RORγ expression is associated with ECM remodeling and metastasis in patients with HCC. Taken together, we identify RORγ as a key player of ECM remodeling in HCC and as an attractive therapeutic target for advanced HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animales , Ratones , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/metabolismo , Línea Celular Tumoral , Sorafenib , Colágeno/metabolismo , Microambiente Tumoral
6.
Mol Cell Proteomics ; 22(4): 100525, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36871861

RESUMEN

Energy homeostasis of mammals during cold exposure involves complicated neural regulation and is affected by gut microbiota. However, the regulatory mechanism remains unclear partially due to a lack of comprehensive knowledge of the signaling molecules involved. Herein, we performed region-resolvable quantitative profiling of the brain peptidome using cold-exposed mouse models and interrogated the interaction between gut microbes and brain peptides in response to cold. Region-specific alterations in the brain peptidome were observed during chronic cold exposure and were correlated with gut microbiome composition. Several proSAAS-derived peptides exhibited a positive correlation with Lactobacillus. The hypothalamus-pituitary axis exhibited a sensitive response to cold exposure. We obtained a candidate pool of bioactive peptides that potentially participate in the regulation of cold-induced energy homeostasis. Intervention with cold-adapted microbiota in mice decreased the abundance of hypothalamic neurokinin B and subsequently contributed to shifting the fuel source for energy consumption from lipids to glucose. Collectively, this study demonstrated that gut microbes modulate brain peptides contributing to energy metabolism, providing a data resource for understanding the regulatory mechanism of energy homeostasis upon cold exposure.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Animales , Ratones , Microbioma Gastrointestinal/fisiología , Encéfalo/metabolismo , Metabolismo Energético , Homeostasis , Mamíferos
7.
Proc Natl Acad Sci U S A ; 119(18): e2123020119, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35446689

RESUMEN

The peristaltic reflex is a fundamental behavior of the gastrointestinal (GI) tract in which mucosal stimulation activates propulsive contractions. The reflex occurs by stimulation of intrinsic primary afferent neurons with cell bodies in the myenteric plexus and projections to the lamina propria, distribution of information by interneurons, and activation of muscle motor neurons. The current concept is that excitatory cholinergic motor neurons are activated proximal to and inhibitory neurons are activated distal to the stimulus site. We found that atropine reduced, but did not block, colonic migrating motor complexes (CMMCs) in mouse, monkey, and human colons, suggesting a mechanism other than one activated by cholinergic neurons is involved in the generation/propagation of CMMCs. CMMCs were activated after a period of nerve stimulation in colons of each species, suggesting that the propulsive contractions of CMMCs may be due to the poststimulus excitation that follows inhibitory neural responses. Blocking nitrergic neurotransmission inhibited poststimulus excitation in muscle strips and blocked CMMCs in intact colons. Our data demonstrate that poststimulus excitation is due to increased Ca2+ transients in colonic interstitial cells of Cajal (ICC) following cessation of nitrergic, cyclic guanosine monophosphate (cGMP)-dependent inhibitory responses. The increase in Ca2+ transients after nitrergic responses activates a Ca2+-activated Cl− conductance, encoded by Ano1, in ICC. Antagonists of ANO1 channels inhibit poststimulus depolarizations in colonic muscles and CMMCs in intact colons. The poststimulus excitatory responses in ICC are linked to cGMP-inhibited cyclic adenosine monophosphate (cAMP) phosphodiesterase 3a and cAMP-dependent effects. These data suggest alternative mechanisms for generation and propagation of CMMCs in the colon.


Asunto(s)
Células Intersticiales de Cajal , Colon/fisiología , Motilidad Gastrointestinal/fisiología , Miocitos del Músculo Liso , Peristaltismo
8.
J Cell Mol Med ; 28(11): e18366, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38856956

RESUMEN

Ischemic stroke is one of the main causes of disability and death. However, recanalization of occluded cerebral arteries is effective only within a very narrow time window. Therefore, it is particularly important to find neuroprotective biological targets for cerebral artery recanalization. Here, gene expression profiles of datasets GSE160500 and GSE97537 were downloaded from the GEO database, which were related to ischemic stroke in rats. Olfactory receptor 78 (Olfr78) was screened, and which highly associated with Calcium signalling pathway and MAPK pathway. Interacting protein of Olfr78, Prkaca, was predicted by STRING, and their interaction was validated by Co-IP analysis. Then, a rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) and a neuronal cell model stimulated by oxygen-glucose deprivation/reoxygenation (OGD/R) were constructed, and the results showed that expression of Olfr78 and Prkaca was downregulated in MCAO rats and OGD/R-stimulated neurons. Overexpression of Olfr78 or Prkaca inhibited the secretion of inflammatory factors, Ca2+ overload, and OGD/R-induced neuronal apoptosis. Moreover, Overexpression of Prkaca increased protein levels of cAMP, PKA and phosphorylated p38 in OGD/R-stimulated neurons, while SB203580, a p38 inhibitor, treatment inhibited activation of the cAMP/PKA-MAPK pathway and counteracted the effect of Olfr78 overexpression on improvement of neuronal functions. Meanwhile, overexpression of Olfr78 or Prkaca markedly inhibited neuronal apoptosis and improved brain injury in MCAO/R rats. In conclusion, overexpression of Olfr78 inhibited Ca2+ overload and reduced neuronal apoptosis in MCAO/R rats by promoting Prkaca-mediated activation of the cAMP/PKA-MAPK pathway, thereby improving brain injury in cerebral ischaemia-reperfusion.


Asunto(s)
Apoptosis , AMP Cíclico , Ratas Sprague-Dawley , Receptores Odorantes , Daño por Reperfusión , Animales , Daño por Reperfusión/metabolismo , Daño por Reperfusión/genética , Ratas , Masculino , AMP Cíclico/metabolismo , Receptores Odorantes/metabolismo , Receptores Odorantes/genética , Isquemia Encefálica/metabolismo , Isquemia Encefálica/genética , Isquemia Encefálica/patología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/etiología , Lesiones Encefálicas/patología , Neuronas/metabolismo , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media/metabolismo , Transducción de Señal
9.
J Biomol NMR ; 78(2): 87-94, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38530516

RESUMEN

The fast motions of proteins at the picosecond to nanosecond timescale, known as fast dynamics, are closely related to protein conformational entropy and rearrangement, which in turn affect catalysis, ligand binding and protein allosteric effects. The most used NMR approach to study fast protein dynamics is the model free method, which uses order parameter S2 to describe the amplitude of the internal motion of local group. However, to obtain order parameter through NMR experiments is quite complex and lengthy. In this paper, we present a machine learning approach for predicting backbone 1H-15N order parameters based on protein NMR structure ensemble. A random forest model is used to learn the relationship between order parameters and structural features. Our method achieves high accuracy in predicting backbone 1H-15N order parameters for a test dataset of 10 proteins, with a Pearson correlation coefficient of 0.817 and a root-mean-square error of 0.131.


Asunto(s)
Aprendizaje Automático , Resonancia Magnética Nuclear Biomolecular , Conformación Proteica , Proteínas , Proteínas/química , Resonancia Magnética Nuclear Biomolecular/métodos
10.
BMC Plant Biol ; 24(1): 313, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654158

RESUMEN

The enzyme glutamine synthetase (GLN) is mainly responsible for the assimilation and reassimilation of nitrogen (N) in higher plants. Although the GLN gene has been identified in various plants, there is little information about the GLN family in cotton (Gossypium spp.). To elucidate the roles of GLN genes in cotton, we systematically investigated and characterized the GLN gene family across four cotton species (G. raimondii, G. arboreum, G. hirsutum, and G. barbadense). Our analysis encompassed analysis of members, gene structure, cis-element, intragenomic duplication, and exploration of collinear relationships. Gene duplication analysis indicated that segmental duplication was the primary driving force for the expansion of the GhGLN gene family. Transcriptomic and quantitative real-time reverse-transcription PCR (qRT-PCR) analyses indicated that the GhGLN1.1a gene is responsive to N induction treatment and several abiotic stresses. The results of virus-induced gene silencing revealed that the accumulation and N use efficiency (NUE) of cotton were affected by the inactivation of GhGLN1.1a. This study comprehensively analyzed the GhGLN genes in Gossypium spp., and provides a new perspective on the functional roles of GhGLN1.1a in regulating NUE in cotton.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Glutamato-Amoníaco Ligasa , Gossypium , Nitrógeno , Proteínas de Plantas , Duplicación de Gen , Genes de Plantas , Glutamato-Amoníaco Ligasa/genética , Glutamato-Amoníaco Ligasa/metabolismo , Gossypium/genética , Gossypium/metabolismo , Familia de Multigenes , Nitrógeno/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
11.
Small ; 20(26): e2310769, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38263803

RESUMEN

Inspired by natural swarms, various methods are developed to create artificial magnetic microrobotic collectives. However, these magnetic collectives typically receive identical control inputs from a common external magnetic field, limiting their ability to operate independently. And they often rely on interfaces or boundaries for controlled movement, posing challenges for independent, three-dimensional(3D) navigation of multiple magnetic collectives. To address this challenge, self-assembled microrobotic collectives are proposed that can be selectively actuated in a combination of external magnetic and optical fields. By harnessing both actuation methods, the constraints of single actuation approaches are overcome. The magnetic field excites the self-assembly of colloids and maintains the self-assembled microrobotic collectives without disassembly, while the optical field drives selected microrobotic collectives to perform different tasks. The proposed magnetic-photo microrobotic collectives can achieve independent position and path control in the two-dimensional (2D) plane and 3D space. With this selective control strategy, the microrobotic collectives can cooperate in convection and mixing the dye in a confined space. The results present a systematic approach for realizing selective control of multiple microrobotic collectives, which can address multitasking requirements in complex environments.

12.
Small ; : e2308071, 2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38342680

RESUMEN

Infections induced by Gram-positive bacteria pose a great threat to public health. Antibiotic therapy, as the first chosen strategy against Gram-positive bacteria, is inevitably associated with antibiotic resistance selection. Novel therapeutic strategies for the discrimination and inactivation of Gram-positive bacteria are thus needed. Here, a specific type of aggregation-induced emission luminogen (AIEgen) with near-infrared fluorescence emission as a novel antibiotic-free therapeutic strategy against Gram-positive bacteria is proposed. With the combination of a positively charged group into a highly twisted architecture, self-assembled AIEgens (AIE nanoparticles (NPs)) at a relatively low concentration (5 µm) exhibited specific binding and photothermal effect against living Gram-positive bacteria both in vitro and in vivo. Moreover, toxicity assays demonstrated excellent biocompatibility of AIE NPs at this concentration. All these properties make the AIE NPs as a novel generation of theranostic platform for combating Gram-positive bacteria and highlight their promising potential for in vivo tracing of such bacteria.

13.
Clin Exp Immunol ; 216(2): 200-210, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38290436

RESUMEN

Mucosal bile acid (BA) profile is still unestablished in diarrhea-predominant irritable bowel syndrome (IBS-D). The aim of this study was to explore colonic mucosal BAs and their associations with mucosal mast cell (MMC)-derived nerve growth factor (NGF) and bowel symptoms in IBS-D. Colonic mucosal biopsies from 36 IBS-D patients and 35 healthy controls (HCs) were obtained for targeted BA profiling. MMC count and the expression of NGF and tight junction proteins (TJPs) were examined. We found that colonic mucosal BA profile was altered in the IBS-D cohort. The proportion of primary BAs was significantly higher and that of secondary BAs was lower in IBS-D patients. According to the 90th percentile of total mucosal BA content of HCs, IBS-D patients were divided into BA-H (n = 7, 19.4%) and BA-L (n = 29, 80.6%) subgroups. BA-H patients showed significantly higher total mucosal BA content compared to BA-L subgroup and HCs. The mucosal content of 11 BA metabolites significantly increased in BA-H subgroup, e.g. cholic acid (CA) and taurocholic acid (TCA). Moreover, BA-H patients displayed significantly elevated MMC count and NGF expression, with decreased expression of TJPs (claudin-1, junctional adhesion molecule-A and zonula occludens-1). Correlation analyses revealed that mucosal TCA content positively correlated with MMC count, MMC-derived NGF levels, and abdominal pain while negatively correlated with TJP expression. In conclusion, IBS-D patients showed an altered BA profile in the colonic mucosa. Approximately 20% of them exhibit elevated mucosal BA content, which may be associated with MMC-derived NGF signaling and bowel symptoms.

14.
Blood ; 140(12): 1390-1407, 2022 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-35544603

RESUMEN

Recurrent MEF2D fusions with poor prognosis have been identified in B-cell precursor ALL (BCP-ALL). The molecular mechanisms underlying the pathogenic function of MEF2D fusions are poorly understood. Here, we show that MEF2D-HNRNPUL1 (MH) knock-in mice developed a progressive disease from impaired B-cell development at the pre-pro-B stage to pre-leukemia over 10 to 12 months. When cooperating with NRASG12D, MH drove an outbreak of BCP-ALL, with a more aggressive phenotype than the NRASG12D-induced leukemia. RNA-sequencing identified key networks involved in disease mechanisms. In chromatin immunoprecipitation-sequencing experiments, MH acquired increased chromatin-binding ability, mostly through MEF2D-responsive element (MRE) motifs in target genes, compared with wild-type MEF2D. Using X-ray crystallography, the MEF2D-MRE complex was characterized in atomic resolution, whereas disrupting the MH-DNA interaction alleviated the aberrant target gene expression and the B-cell differentiation arrest. The C-terminal moiety (HNRNPUL1 part) of MH was proven to contribute to the fusion protein's trans-regulatory activity, cofactor recruitment, and homodimerization. Furthermore, targeting MH-driven transactivation of the HDAC family by using the histone deacetylase inhibitor panobinostat in combination with chemotherapy improved the overall survival of MH/NRASG12D BCP-ALL mice. Altogether, these results not only highlight MH as an important driver in leukemogenesis but also provoke targeted intervention against BCP-ALL with MEF2D fusions.


Asunto(s)
Proteínas de Fusión Oncogénica , Leucemia-Linfoma Linfoblástico de Células Precursoras , Animales , Cromatina , ADN/metabolismo , Inhibidores de Histona Desacetilasas , Factores de Transcripción MEF2/genética , Factores de Transcripción MEF2/metabolismo , Ratones , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Panobinostat , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , ARN
15.
Opt Express ; 32(4): 4998-5010, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439237

RESUMEN

Aiming to enhance the ns-LIBS signal, in this work, we introduced orbital angular momentum to modulate the laser phase of the Gaussian beam into the vortex beam. Under similar incident laser energy, the vortex beam promoted more uniform ablation and more ablation mass compared to the Gaussian beam, leading to elevated temperature and electron density in the laser-induced plasma. Consequently, the intensity of the ns-LIBS signal was improved. The enhancement effects based on the laser phase modulation were investigated on both metallic and non-metallic samples. The results showed that laser phase modulation resulted in a maximum 1.26-times increase in the peak intensities and a maximum 1.25-times increase in the signal-to-background ratio (SBR) of the Cu spectral lines of pure copper for a laser energy of 10 mJ. The peak intensities of Si atomic spectral lines were enhanced by 1.58-1.94 times using the vortex beam. Throughout the plasma evolution process, the plasma induced by the vortex beam exhibited prolonged duration and a longer continuous background, accompanied by a noticeable reduction in the relative standard deviation (RSD). The experimental results demonstrated that modulation the laser phase based on orbital angular momentum is a promising approach to enhancing the ns-LIBS signal.

16.
Invest New Drugs ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38880855

RESUMEN

Radioresistance is an inevitable obstacle in the clinical treatment of inoperable patients with non-small cell lung cancer (NSCLC). Combining treatment with radiosensitizers may improve the efficacy of radiotherapy. Previously, the quinoline derivative 10E as new exporter of Nur77 has shown superior antitumor activity in hepatocellular carcinoma. Here, we aimed to investigate the radiosensitizing activity and acting mechanisms of 10E. In vitro, A549 and H460 cells were treated with control, ionizing radiation (IR), 10E, and 10E + IR. Cell viability, apoptosis, and cycle were examined using CCK-8 and flow cytometry assays. Protein expression and localization were examined using western blotting and immunofluorescence. Tumor xenograft models were established to evaluate the radiosensitizing effect of 10E in vivo. 10E significantly inhibited cell proliferation and increased their radiosensitivity while reducing level of p-BCRA1, p-DNA-PKs, and 53BP1 involved in the DNA damage repair pathway, indicating that its radiosensitizing activity is closely associated with repressing DNA damage repair. A549 cells showed low level of Nur77 and a low response to IR but 10E-treated A549 cells showed high level of Nur77 indicating that Nur77 is a core radiosensitivity factor and 10E restores the expression of Nur77. Nur77 and Ku80 extranuclear co-localization in the 10E-treated A549 cells suggested that 10E-modulated Nur77 nuclear exportation inhibits DNA damage repair pathways and increases IR-triggered apoptosis. The combination of 10E and IR significantly inhibits tumor growth in a tumor xenograft model. Our findings suggest that 10E acts as a radiosensitizer and that combining 10E with radiotherapy may be a potential strategy for NSCLC treatment.

17.
FASEB J ; 37(10): e23175, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37742293

RESUMEN

Many studies have highlighted the importance of moderate exercise. While it can attenuate diabetic kidney disease, its mechanism has remained unclear. The level of myokine irisin in plasma increases during exercise. We found that irisin was decreased in diabetic patients and was closely related to renal function, proteinuria, and podocyte autophagy injury. Muscle-specific overexpression of PGC-1α (mPGC-1α) in a mouse model is known to increase plasma irisin levels. The mPGC-1α mice were crossed with db/m mice to obtain db/db mPGC-1α+ mice in the present study. Compared to db/db mice without mPGC-1α, plasma irisin was increased, and albuminuria and glomerular pathological damage were both alleviated in db/db mPGC-1α+ mice. Impaired autophagy in podocytes was restored as well. Irisin inhibited the activation of the PI3K/AKT/mTOR signaling pathway in cultured human podocytes and improved damaged autophagy induced by high glucose levels. Then, db/db mice were treated with recombinant irisin, which had similar beneficial effects on the kidney as those in db/db mPGC-1α+ mice, with alleviated glomerular injury and albuminuria. Moreover, the autophagy in podocytes was also significantly restored. These results suggest that irisin secreted by skeletal muscles protects the kidney from diabetes mellitus damage. It also restores autophagy in podocytes by inhibiting the abnormal activation of the PI3K/AKT/mTOR signaling pathway. Thus, irisin may become a new drug for the prevention and treatment of diabetic nephropathy.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Podocitos , Humanos , Ratones , Animales , Podocitos/metabolismo , Nefropatías Diabéticas/metabolismo , Fibronectinas/metabolismo , Albuminuria/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Autofagia , Serina-Treonina Quinasas TOR/metabolismo , Diabetes Mellitus/metabolismo
18.
FASEB J ; 37(3): e22822, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36809666

RESUMEN

Islet fibrosis is associated with the disruption of islet structure and contributes to ß-cell dysfunction, playing an essential role in the pathogenesis of type 2 diabetes. Physical exercise has been shown to attenuate fibrosis in various organs; however, the effect of exercise on islet fibrosis has not been defined. Male Sprague-Dawley rats were divided into four groups: normal diet sedentary [N-Sed], normal diet + exercise [N-Ex], high-fat diet sedentary [H-Sed], and high-fat diet + exercise [H-Ex]. After 60 weeks of exercise, 4452 islets from Masson-stained slides were analyzed. Exercise led to a 68% and 45% reduction in islet fibrosis in the normal and high-fat diet groups and was correlated with a lower serum blood glucose. Fibrotic islets were characterized by irregular shapes and substantial loss of ß-cell mass, which were significantly reduced in the exercise groups. Remarkably, the islets from exercised rats at week 60 were morphologically comparable to those of sedentary rats at 26 weeks. In addition, the protein and RNA levels of collagen and fibronectin, and the protein levels of hydroxyproline in the islets were also attenuated by exercise. This was accompanied by a significant reduction in inflammatory markers in the circulation Interleukin-1 beta (IL-1ß)] and pancreas [IL-1ß, Tumor Necrosis Factor-alpha, Transforming Growth Factor-ß, and Phosphorylated Nuclear Factor Kappa-B p65 subunit], lower macrophage infiltration, and stellate cell activation in the islets of exercised rats. In conclusion, we have demonstrated that long-term exercise preserves pancreatic islet structure and ß-cell mass through anti-inflammatory and anti-fibrotic actions, suggesting additional rationales for the success of exercise training in the prevention and treatment of type 2 diabetes that should be further explored.


Asunto(s)
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Islotes Pancreáticos , Masculino , Ratas , Animales , Diabetes Mellitus Tipo 2/metabolismo , Ratas Sprague-Dawley , Páncreas/metabolismo , Células Secretoras de Insulina/metabolismo , Fibrosis , Inflamación/metabolismo , Islotes Pancreáticos/metabolismo
19.
Theor Appl Genet ; 137(1): 24, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38236415

RESUMEN

KEY MESSAGE: A novel quantitative trait locus qIGL1, which performed a positive function in regulating grain length in rice, was cloned by the map-based cloning approach; further studies revealed that it corresponded to LOC_Os03g30530, and the IGL1 appeared to contribute to lengthening and widening of the cells on the surface of grain hulls. Grain length is a prominent determinant for grain weight and appearance quality of rice. In this study, we conducted quantitative trait locus mapping to determine a genomic interval responsible for a long-grain phenotype observed in a japonica cultivar HD385. This led to the identification of a novel QTL for grain length on chromosome 3, named qIGL1 (for Increased Grain Length 1); the HD385 (Handao 385)-derived allele showed enhancement effects on grain length, and such an allele as well as NIP (Nipponbare)-derived allele was designated qigl1 HD385 and qIGL1NIP, respectively. Genetic analysis revealed that the qigl1HD385 allele displayed semidominant effects on grain length. Fine mapping further narrowed down the qIGL1 to an ~ 70.8-kb region containing 9 open reading frames (ORFs). A comprehensive analysis indicated that LOC_Os03g30530, which corresponded to ORF6 and carried base substitutions and deletions in HD385 relative to NIP, thereby causing changes or losses of amino-acid residues, was the true gene for qIGL1. Comparison of grain traits between a pair of near-isogenic lines (NILs), termed NIL-igl1HD385 and NIL-IGL1NIP, discovered that introduction of the igl1HD385 into the NIP background significantly resulted in the elevations of grain length and 1000-grain weight. Closer inspection of grain surfaces revealed that the cell length and width in the longitudinal direction were significantly longer and greater, respectively, in NIL-igl1HD385 line compared with in NIL-IGL1NIP line. Hence, our studies identified a new semidominant natural allele contributing to the increase of grain length and further shed light on the regulatory mechanisms of grain length.


Asunto(s)
Oryza , Sitios de Carácter Cuantitativo , Oryza/genética , Alelos , Mapeo Cromosómico , Aminoácidos , Grano Comestible/genética
20.
Nutr Cancer ; 76(7): 619-627, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38775076

RESUMEN

Vitamin B12 plays a role in DNA methylation, influencing the 1-carbon cycle; However, its effect on colorectal cancer (CRC) mortality remains uncertain. This study assessed the relationship between vitamin B12 intake and all-cause and cancer-specific mortality among CRC patients. We analyzed data from the NHANES from 1999 to 2018, using multivariable Cox regression, competing risk model, Kaplan-Meier survival curves, and stratified analysis with interaction effects. The studied involved 4,554 cancer patients (mean age 65.8 years, 47.6% males). Results from multivariate Cox regression indicated that each additional 1 mcg/day of dietary vitamin B12 independently increased the risk of all-cause (HR, 1.07; 95% CI: 1.04-1.09, p < 0.001) and cancer-specific mortality (HR, 1.04; 95% CI, 1.02-1.06; p < 0.001). Kaplan-Meier curves indicated a higher risk of all-cause mortality with increased vitamin B12 intake (Log rank p = 0.01). Subgroup analysis suggested that higher vitamin B12 intake correlated with increased all-cause mortality risk, especially in individuals with higher protein (HR, 1.04; 95% CI, 1.02-1.06; p = 0.019) or carbohydrate intake (HR, 1.03; 95% CI, 1.01-1.05; p = 0.04). Thus, higher vitamin B12 intake correlates with increased all-cause and cancer-specific mortality in CRC patients, particularly those with higher protein or carbohydrate intake.


Asunto(s)
Neoplasias Colorrectales , Encuestas Nutricionales , Vitamina B 12 , Humanos , Neoplasias Colorrectales/mortalidad , Masculino , Vitamina B 12/administración & dosificación , Femenino , Anciano , Persona de Mediana Edad , Estados Unidos/epidemiología , Dieta , Modelos de Riesgos Proporcionales , Estimación de Kaplan-Meier , Factores de Riesgo
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