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1.
Cell Metab ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38718794

RESUMO

Although mechanical loading is essential for maintaining bone health and combating osteoporosis, its practical application is limited to a large extent by the high variability in bone mechanoresponsiveness. Here, we found that gut microbial depletion promoted a significant reduction in skeletal adaptation to mechanical loading. Among experimental mice, we observed differences between those with high and low responses to exercise with respect to the gut microbial composition, in which the differential abundance of Lachnospiraceae contributed to the differences in bone mechanoresponsiveness. Microbial production of L-citrulline and its conversion into L-arginine were identified as key regulators of bone mechanoadaptation, and administration of these metabolites enhanced bone mechanoresponsiveness in normal, aged, and ovariectomized mice. Mechanistically, L-arginine-mediated enhancement of bone mechanoadaptation was primarily attributable to the activation of a nitric-oxide-calcium positive feedback loop in osteocytes. This study identifies a promising anti-osteoporotic strategy for maximizing mechanical loading-induced skeletal benefits via the microbiota-metabolite axis.

2.
J Med Genet ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38508705

RESUMO

BACKGROUND: The ZFHX3 gene plays vital roles in embryonic development, cell proliferation, neuronal differentiation and neuronal death. This study aims to explore the relationship between ZFHX3 variants and epilepsy. METHODS: Whole-exome sequencing was performed in a cohort of 378 patients with partial (focal) epilepsy. A Drosophila Zfh2 knockdown model was used to validate the association between ZFHX3 and epilepsy. RESULTS: Compound heterozygous ZFHX3 variants were identified in eight unrelated cases. The burden of ZFHX3 variants was significantly higher in the case cohort, shown by multiple/specific statistical analyses. In Zfh2 knockdown flies, the incidence and duration of seizure-like behaviour were significantly greater than those in the controls. The Zfh2 knockdown flies exhibited more firing in excitatory neurons. All patients presented partial seizures. The five patients with variants in the C-terminus/N-terminus presented mild partial epilepsy. The other three patients included one who experienced frequent non-convulsive status epilepticus and two who had early spasms. These three patients had also neurodevelopmental abnormalities and were diagnosed as developmental epileptic encephalopathy (DEE), but achieved seizure-free after antiepileptic-drug treatment without adrenocorticotropic-hormone/steroids. The analyses of temporal expression (genetic dependent stages) indicated that ZFHX3 orthologous were highly expressed in the embryonic stage and decreased dramatically after birth. CONCLUSION: ZFHX3 is a novel causative gene of childhood partial epilepsy and DEE. The patients of infantile spasms achieved seizure-free after treatment without adrenocorticotropic-hormone/steroids implies a significance of genetic diagnosis in precise treatment. The genetic dependent stage provided an insight into the underlying mechanism of the evolutional course of illness.

3.
Nurse Educ Pract ; 75: 103900, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38277802

RESUMO

AIMS: Development and evaluation of the effectiveness of a Nurse Navigation programme based on Noddings' Care theory on two dependent variables which were professional identity and career planning among first-year undergraduate nursing students. BACKGROUND: First-year undergraduate nursing students generally have a low sense of professional identity and career planning, resulting in a loss of nursing power after graduation. Implemention of a Nurse Navigation program based on Noddings' Care theory may be potentially useful in cultivating their professional identity and career planning. DESIGN: A quasi-experimental study. METHODS: A convenience sample of 122 first-year undergraduate nursing students from two medical universities was recruited between September 2021 and June 2022. Students in the experimental group (n = 63) participated in the Nurse Navigation programme based on Noddings' Care theory, which contained four core components, spreading over 50 lessons. Those in the control group (n = 59) underwent a traditional training programme with five components across 44 lessons. The two groups were compared in terms of their level of professional identity by Professional identity questionnaire for nurse students (PIQNS) and career planning by Career planning questionnaire (CPQ) after the training using the t-test. RESULTS: The mean score of professional identity in the experimental group increased significantly from 51.02 ± 8.46 at baseline to 58.02 ± 8.81 after the intervention (p < 0.001), with a large effect size (Cohen's d=0.810). Also, this post-intervention score was statistically significantly higher than that (52.86 ± 9.27) in the control group (p = 0.002), with a medium effect size (Cohen's d=0.571). The mean score of career planning in the experimental group increased significantly from 81.76 ± 9.86 at baseline to 94.52 ± 10.81 after the intervention (p < 0.001), with a large effect size (Cohen's d = 1.233). Also, this post-intervention score was statistically significantly higher than that (88.25 ± 9.30) in the control group (p < 0.001), with a medium effect size (Cohen's d=0.623). CONCLUSIONS: The Nurse Navigation programme based on Noddings' Care theory showed effectiveness in enhancing professional identity and career planning among first-year undergraduate nursing students in China. Further rigorous studies are needed to examine its effectiveness and long-term impacts on these students.


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , Humanos , Bacharelado em Enfermagem/métodos , Currículo , China
4.
Nat Commun ; 15(1): 890, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291059

RESUMO

Type 2 diabetes (T2D)-related fragility fractures represent an increasingly tough medical challenge, and the current treatment options are limited. Mechanical loading is essential for maintaining bone integrity, although bone mechano-responsiveness in T2D remains poorly characterized. Herein, we report that exogenous cyclic loading-induced improvements in bone architecture and strength are compromised in both genetically spontaneous and experimentally-induced T2D mice. T2D-induced reduction in bone mechano-responsiveness is directly associated with the weakened Ca2+ oscillatory dynamics of osteocytes, although not those of osteoblasts, which is dependent on PPARα-mediated specific reduction in osteocytic SERCA2 pump expression. Treatment with the SERCA2 agonist istaroxime was demonstrated to improve T2D bone mechano-responsiveness by rescuing osteocyte Ca2+ dynamics and the associated regulation of osteoblasts and osteoclasts. Moreover, T2D-induced deterioration of bone mechano-responsiveness is blunted in mice with osteocytic SERCA2 overexpression. Collectively, our study provides mechanistic insights into T2D-mediated deterioration of bone mechano-responsiveness and identifies a promising countermeasure against T2D-associated fragility fractures.


Assuntos
Diabetes Mellitus Tipo 2 , Osteócitos , Animais , Camundongos , Osso e Ossos , Cálcio/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Osteoblastos/metabolismo , Osteócitos/metabolismo
5.
Seizure ; 116: 30-36, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36894399

RESUMO

OBJECTIVES: The MED12 gene encodes mediator complex subunit 12, which is a component of the mediator complex involved in the transcriptional regulation of nearly all RNA polymerase II-dependent genes. MED12 variants have previously been associated with developmental disorders with or without nonspecific intellectual disability. This study aims to explore the association between MED12 variants and epilepsy. MATERIALS AND METHODS: Trios-based whole-exome sequencing was performed in a cohort of 349 unrelated cases with partial (focal) epilepsy without acquired causes. The genotype-phenotype correlations of MED12 variants were analyzed. RESULTS: Five hemizygous missense MED12 variants, including c.958A>G/p.Ile320Val, c.1757G>A/p.Ser586Asn, c.2138C>T/p.Pro713Leu, c.3379T>C/p.Ser1127Pro, and c.4219A>C/p.Met1407Leu were identified in five unrelated males with partial epilepsy. All patients showed infrequent focal seizures and achieved seizure free without developmental abnormalities or intellectual disability. All the hemizygous variants were inherited from asymptomatic mothers (consistent with the X-linked recessive inheritance pattern) and were absent in the general population. The two variants with damaging hydrogen bonds were associated with early-onset seizures. Further genotype-phenotype analysis revealed that congenital anomaly disorder (Hardikar syndrome) was associated with (de novo) destructive variants in an X-linked dominant inheritance pattern, whereas epilepsy was associated with missense variants in an X-linked recessive inheritance pattern. Phenotypic features of intellectual disability appeared as the intermediate phenotype in terms of both genotype and inheritance. Epilepsy-related variants were located at the MED12-LCEWAV domain and the regions between MED12-LCEWAV and MED12-POL. CONCLUSION: MED12 is a potentially causative gene for X-linked recessive partial epilepsy without developmental or intellectual abnormalities. The genotype-phenotype correlation of MED12 variants explains the phenotypic variations and can help the genetic diagnosis.


Assuntos
Epilepsias Parciais , Epilepsia , Deficiência Intelectual , Masculino , Humanos , Deficiência Intelectual/genética , Genes Ligados ao Cromossomo X/genética , Fenótipo , Complexo Mediador/genética , Complexo Mediador/química , Complexo Mediador/metabolismo , Epilepsias Parciais/genética , Epilepsia/genética , Fatores de Transcrição/genética
6.
ACS Appl Mater Interfaces ; 15(46): 54050-54059, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37956100

RESUMO

Narrowband photodetectors have wide application potential in high-resolution imaging and encrypted communication, due to their high-precision spectral resolution capability. In this work, we report a fast response, high spectral rejection ratio, and self-filtered ultranarrowband photodetector with a new mechanism, which introduces bulk recombination by doping Bi3+ and cooperates with surface recombination for further quenching photogenerated charges generated by short-wavelength-light excitation in perovskite single-crystal. A perovskite film focused on collecting charges is fabricated on the single crystal by a lattice-matched solution-processed epitaxial growth method. Due to the formation of PN heterojunctions, a narrowband photodetector in this mechanism has remarkable spectral selectivity and detection performance with an ultranarrow full width at half-maximum (FWHM) of 7.7 nm and a high spectral rejection ratio of 790, as well as a high specific detectivity up to 1.5 × 1010 Jones, a fast response speed with a rise time and fall time of ∼8 and 137 µs. The ultrafast and ultranarrow spectra response of self-filtered narrowband photodetector provides a new strategy in high-precision and high-resolution photoelectric detection.

7.
J Vis Exp ; (200)2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37902337

RESUMO

Epilepsy is a neurological disorder characterized by recurrent seizures, partially correlated with genetic origin, affecting over 70 million individuals worldwide. Despite the clinical importance of epilepsy, the functional analysis of neural activity in the central nervous system is still to be developed. Recent advancements in imaging technology, in combination with stable expression of genetically encoded calcium indicators, such as GCaMP6, have revolutionized the study of epilepsy at both brain-wide and single-cell resolution levels. Drosophila melanogaster has emerged as a tool for investigating the molecular and cellular mechanisms underlying epilepsy due to its sophisticated molecular genetics and behavioral assays. In this study, we present a novel and efficient protocol for ex vivo calcium imaging in GCaMP6-expressing adult Drosophila to monitor epileptiform activities. The whole brain is prepared from cac, a well-known epilepsy gene, knockdown flies for calcium imaging with a confocal microscope to identify the neural activity as a follow-up to the bang-sensitive seizure-like behavior assay. The cac knockdown flies showed a higher rate of seizure-like behavior and abnormal calcium activities, including more large spikes and fewer small spikes than wild-type flies. The calcium activities were correlated to seizure-like behavior. This methodology serves as an efficient methodology in screening the pathogenic genes for epilepsy and exploring the potential mechanism of epilepsy at the cellular level.


Assuntos
Drosophila , Epilepsia , Animais , Humanos , Drosophila melanogaster/genética , Cálcio , Epilepsia/diagnóstico por imagem , Epilepsia/genética , Convulsões/patologia
8.
Huan Jing Ke Xue ; 44(10): 5392-5399, 2023 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-37827757

RESUMO

In recent years, the situation of ozone pollution in China has become increasingly severe, with PM2.5 being the main pollutant in the atmospheric environment of several cities. Meteorological conditions, particularly temperature and humidity, have a great influence on ozone formation. Therefore, understanding and quantifying the impact of the variation in temperature and humidity on ozone level can effectively provide the theoretical basis for the government to prevent and control ozone pollution. By analyzing the relationship among the daily maximum temperature (Tmax), relative humidity (RH), and the maximum 8-h running average ozone (O3-8h) measured from January 1, 2015 to July 31, 2022, a linear positive correlation between O3-8h and Tmax was observed in the seven regions with serious ozone pollution, and the temperature penalty factor ranged from 2.1-6.0 µg·(m3·â„ƒ)-1; a nonlinear correlation between O3-8h and RH was also observed, and O3-8h was the highest when RH was 55%. The sensitivity of different regions to Tmax and RH was slightly different; generally, the most suitable meteorological conditions for ozone formation were 29℃ ≤ Tmax< 38℃ and 40% ≤ RH<70%. In the Yangtze River Delta, Jiangsu-Anhui-Shandong-Henan, and the middle reaches of the Yangtze River, under extreme high temperature conditions (Tmax ≥ 35℃), O3-8h stopped increasing with the increase in temperature and even dropped; simultaneously, it was often accompanied with a small increase in particulate matter. It may be related to the heterogeneous reaction of some precursors with higher water vapor content and the increase in ozone heterogeneous sink.

9.
iScience ; 26(9): 107605, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37664634

RESUMO

Bone stress injuries are common overuse injuries, especially in soldiers, athletes, and performers. In contrast to various post-injury treatments, early protection against bone stress injuries can provide greater benefit. This study explored the early protection strategies against bone stress injuries by mobilization of endogenous targeted bone remodeling. The effects of various pharmaceutical/biophysical approaches, individual or combinational, were investigated by giving intervention before fatigue loading. We optimized the dosage and administration parameters and found that early intervention with pulsed electromagnetic field and parathyroid hormone (i.e., PEMF+PTH) resulted in the most pronounced protective effects among all the approaches against the bone stress injuries. In addition, the mechanisms by which the strategy mobilizes targeted bone remodeling and enhances the self-repair capacity of bone were systematically investigated. This study proposes strategies to reduce the incidence of bone stress injuries in high-risk populations (e.g., soldiers and athletes), particularly for those before sudden increased physical training.

10.
Front Endocrinol (Lausanne) ; 14: 1165825, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37529615

RESUMO

Introduction: It has been established that UBR4 encodes E3 ubiquitin ligase, which determines the specificity of substrate binding during protein ubiquitination and has been associated with various functions of the nervous system but not the reproductive system. Herein, we explored the role of UBR4 on fertility with a Drosophila model. Methods: Different Ubr4 knockdown flies were established using the UAS/GAL4 activating sequence system. Fertility, hatchability, and testis morphology were studied, and bioinformatics analyses were conducted. Our results indicated that UBR4 deficiency could induce male sterility and influent egg hatchability in Drosophila. Results: We found that Ubr4 deficiency affected the testis during morphological analysis. Proteomics analysis indicated 188 upregulated proteins and 175 downregulated proteins in the testis of Ubr4 knockdown flies. Gene Ontology analysis revealed significant upregulation of CG11598 and Sfp65A, and downregulation of Pelota in Ubr4 knockdown flies. These proteins were involved in the biometabolic or reproductive process in Drosophila. These regulated proteins are important in testis generation and sperm storage promotion. Bioinformatics analysis verified that UBR4 was low expressed in cryptorchidism patients, which further supported the important role of UBR4 in male fertility. Discussion: Overall, our findings suggest that UBR4 deficiency could promote male infertility and may be involved in the protein modification of UBR4 by upregulating Sfp65A and CG11598, whereas downregulating Pelota protein expression.


Assuntos
Proteínas de Drosophila , Infertilidade Masculina , Humanos , Animais , Masculino , Drosophila , Testículo/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Sêmen/metabolismo , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Proteínas de Ligação a Calmodulina/metabolismo , Ubiquitina-Proteína Ligases/genética
11.
Nurse Educ Today ; 129: 105894, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37467708

RESUMO

BACKGROUND: Currently, a paramount issue in nursing education is to motivate nursing undergraduate interns to develop self-directed learning skills and improve their practice satisfaction and professional identity, so as to meet the growing demands in healthcare. OBJECTIVES: This study aimed to examine the effectiveness of a motivational programme based on the Existence-Relatedness-Growth (ERG) theory in developing self-directed learning skills, improving practice satisfaction and promoting the professional identity of nursing undergraduate interns in China. DESIGN: A quasi-experimental study design. SETTING: A government-funded tertiary teaching hospital in Guangzhou, Guangdong province, China. METHODS: This study was conducted with 99 nursing undergraduate interns in a hospital between June 2020 and April 2022. The interns in the experimental group (n = 50) participated in the motivational programme based on ERG theory, while those in the control group (n = 49) underwent a traditional training programme. The interns in the two groups were compared in terms of their degree of self-directed learning, practice satisfaction and professional identity after the training, using independent samples t-test. RESULTS: After the internship, interns in the experimental group showed a statistically significantly higher level of self-directed learning and practice satisfaction than those in the control group (p < 0.05). However, no significant difference was observed in professional identity between the two groups after the internship. CONCLUSIONS: The motivational programme based on ERG theory was shown to be effective in improving self-directed learning and practice satisfaction in nursing undergraduate interns. A large-scale randomized controlled trial is warranted to confirm the results.


Assuntos
Educação em Enfermagem , Internato e Residência , Estudantes de Enfermagem , Humanos , Aprendizagem , Atenção à Saúde
13.
Front Mol Neurosci ; 16: 1121877, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152436

RESUMO

Introduction: With the advent of trio-based whole-exome sequencing, the identification of epilepsy candidate genes has become easier, resulting in a large number of potential genes that need to be validated in a whole-organism context. However, conducting animal experiments systematically and efficiently remains a challenge due to their laborious and time-consuming nature. This study aims to develop optimized strategies for validating epilepsy candidate genes using the Drosophila model. Methods: This study incorporate behavior, morphology, and electrophysiology for genetic manipulation and phenotypic examination. We utilized the Gal4/UAS system in combination with RNAi techniques to generate loss-of-function models. We performed a range of behavioral tests, including two previously unreported seizure phenotypes, to evaluate the seizure behavior of mutant and wild-type flies. We used Gal4/UAS-mGFP flies to observe the morphological alterations in the brain under a confocal microscope. We also implemented patch-clamp recordings, including a novel electrophysiological method for studying synapse function and improved methods for recording action potential currents and spontaneous EPSCs on targeted neurons. Results: We applied different techniques or methods mentioned above to investigate four epilepsy-associated genes, namely Tango14, Klp3A, Cac, and Sbf, based on their genotype-phenotype correlation. Our findings showcase the feasibility and efficiency of our screening system for confirming epilepsy candidate genes in the Drosophila model. Discussion: This efficient screening system holds the potential to significantly accelerate and optimize the process of identifying epilepsy candidate genes, particularly in conjunction with trio-based whole-exome sequencing.

14.
J Bone Miner Res ; 38(4): 597-614, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36680558

RESUMO

Chronic high-altitude hypoxia induces irreversible abnormalities in various organisms. Emerging evidence indicates that hypobaric hypoxia markedly suppresses bone mass and bone strength. However, few effective means have been identified to prevent such bone deficits. Here, we assessed the potential of pulsed electromagnetic fields (PEMFs) to noninvasively resist bone deterioration induced by hypobaric hypoxia. We observed that exogenous PEMF treatment at 15 Hz and 20 Gauss (Gs) improved the cancellous and cortical bone mass, bone microstructure, and skeletal mechano-properties in rats subjected to chronic exposure of hypobaric hypoxia simulating an altitude of 4500 m for 6 weeks by primarily modulating osteoblasts and osteoblast-mediated bone-forming activity. Moreover, our results showed that whereas PEMF stimulated the functional activity of primary osteoblasts in hypoxic culture in vitro, it had negligible effects on osteoclasts and osteocytes exposed to hypoxia. Mechanistically, the primary cilium was found to function as the major electromagnetic sensor in osteoblasts exposed to hypoxia. The polycystins PC-1/PC-2 complex was identified as the primary calcium channel in the primary cilium of hypoxia-exposed osteoblastic cells responsible for the detection of external PEMF signals, and thereby translated these biophysical signals into intracellular biochemical events involving significant increase in the intracellular soluble adenylyl cyclase (sAC) expression and subsequent elevation of cyclic adenosine monophosphate (cAMP) concentration. The second messenger cAMP inhibited the transcription of oxygen homeostasis-related hypoxia-inducible factor 1-alpha (HIF-1α), and thus enhanced osteoblast differentiation and improved bone phenotype. Overall, the present study not only advances our understanding of bone physiology at high altitudes, but more importantly, proposes effective means to ameliorate high altitude-induced bone loss in a noninvasive and cost-effective manner. © 2023 American Society for Bone and Mineral Research (ASBMR).


Assuntos
Doença da Altitude , Ratos , Animais , Doença da Altitude/metabolismo , Campos Eletromagnéticos , Cílios , Osso e Ossos , Hipóxia/complicações , Hipóxia/metabolismo , Osteoblastos/metabolismo , AMP Cíclico/metabolismo
16.
J Clin Invest ; 133(3)2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36512405

RESUMO

Disuse osteoporosis is a metabolic bone disease resulting from skeletal unloading (e.g., during extended bed rest, limb immobilization, and spaceflight), and the slow and insufficient bone recovery during reambulation remains an unresolved medical challenge. Here, we demonstrated that loading-induced increase in bone architecture/strength was suppressed in skeletons previously exposed to unloading. This reduction in bone mechanosensitivity was directly associated with attenuated osteocytic Ca2+ oscillatory dynamics. The unloading-induced compromised osteocytic Ca2+ response to reloading resulted from the HIF-1α/PDK1 axis-mediated increase in glycolysis, and a subsequent reduction in ATP synthesis. HIF-1α also transcriptionally induced substantial glutaminase 2 expression and thereby glutamine addiction in osteocytes. Inhibition of glycolysis by blockade of PDK1 or glutamine supplementation restored the mechanosensitivity in those skeletons with previous unloading by fueling the tricarboxylic acid cycle and rescuing subsequent Ca2+ oscillations in osteocytes. Thus, we provide mechanistic insight into disuse-induced deterioration of bone mechanosensitivity and a promising therapeutic approach to accelerate bone recovery after long-duration disuse.


Assuntos
Cálcio , Glutamina , Cálcio/metabolismo , Glutamina/farmacologia , Glutamina/metabolismo , Osteócitos/metabolismo , Glucose/metabolismo , Metabolismo Energético
17.
Hum Mol Genet ; 32(3): 462-472, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36001342

RESUMO

YWHAZ encodes an adapter protein 14-3-3ζ, which is involved in many signaling pathways that control cellular proliferation, migration and differentiation. It has not been definitely correlated to any phenotype in OMIM. To investigate the role of YWHAZ gene in intellectual disability and global developmental delay, we conducted whole-exon sequencing in all of the available members from a large three-generation family and we discovered that a novel variant of the YWHAZ gene was associated with intellectual disability and global developmental delay. This variant is a missense mutation of YWHAZ, p.Lys49Asn/c.147A > T, which was found in all affected members but not found in other unaffected members. We also conducted computational modeling and knockdown/knockin with Drosophila to confirm the role of the YWHAZ variant in intellectual disability. Computational modeling showed that the binding energy was increased in the mutated protein combining with the ligand indicating that the c147A > T variation was a loss-of-function variant. Cognitive defects and mushroom body morphological abnormalities were observed in YWHAZ c.147A > T knockin flies. The YWHAZ knockdown flies also manifested serious cognitive defects with hyperactivity behaviors, which is consistent with the clinical features. Our clinical and experimental results consistently suggested that YWHAZ was a novel intellectual disability pathogenic gene.


Assuntos
Deficiência Intelectual , Malformações do Sistema Nervoso , Criança , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/complicações , Proteínas 14-3-3/genética , Mutação de Sentido Incorreto , Encéfalo , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/complicações
18.
Sci Adv ; 8(34): eabq0222, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36001662

RESUMO

Radiotherapy increases tumor cure and survival rates; however, radiotherapy-induced bone damage remains a common issue for which effective countermeasures are lacking, especially considering tumor recurrence risks. We report a high-specificity protection technique based on noninvasive electromagnetic field (EMF). A unique pulsed-burst EMF (PEMF) at 15 Hz and 2 mT induces notable Ca2+ oscillations with robust Ca2+ spikes in osteoblasts in contrast to other waveforms. This waveform parameter substantially inhibits radiotherapy-induced bone loss by specifically modulating osteoblasts without affecting other bone cell types or tumor cells. Mechanistically, primary cilia are identified as major PEMF sensors in osteoblasts, and the differentiated ciliary expression dominates distinct PEMF sensitivity between osteoblasts and tumor cells. PEMF-induced unique Ca2+ oscillations depend on interactions between ciliary polycystins-1/2 and endoplasmic reticulum, which activates the Ras/MAPK/AP-1 axis and subsequent DNA repair Ku70 transcription. Our study introduces a previously unidentified method against radiation-induced bone damage in a noninvasive, cost-effective, and highly specific manner.

19.
Chem Biol Interact ; 364: 110051, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35872049

RESUMO

Formulations against liver fibrosis (LF) mitigate the progression of hepatitis to cirrhosis. However, notable toxicity of the currently available anti-LF drugs limits their long-term use. In the study, we aimed to investigate the anti-LF effects of theacrine, a purine alkaloid without obvious toxicity, on high-fat diet-, alcohol-, and carbon tetrachloride-induced LF in rats. The results indicated that 10 and 20 mg/kg of theacrine ameliorated hepatic fibrosis, steatosis, and inflammation in LF rats. Mechanistically, theacrine reduced hepatic stellate cell (HSC)-related α-smooth muscle actin expression, and decreased cholesterol accumulation, followed by decreased expression of transforming growth factor-ß1, interleukin (IL)-1ß, and tumor necrosis factor (TNF)-α. In addition, theacrine upregulated the phosphorylation of AMP-activated protein kinase, accompanied by decreased expression of ß-catenin and stearoyl-CoA desaturase 1, and increased the expression of sirtuin 3 (SIRT3). Further investigation revealed that the theacrine-mediated decrease in cholesterol was independent of cholesterol synthesis or low-density lipoprotein (LDL) uptake in hyperlipidemia mice. However, theacrine activated farnesoid X receptor (FXR), a ß-catenin conjugated protein, accompanied with decreased expression of cholesterol 7α-hydroxylase and sterol 12α-hydroxylase. In conclusion, theacrine alleviated experimental LF in rats by lowering cholesterol storage and decreasing cholesterol-related HSC activation. A plausible mechanism of theacrine on cholesterol metabolism may involve activation of SIRT3-FXR signaling pathway followed by decreased intestinal cholesterol absorption.


Assuntos
Sirtuína 3 , Animais , Colesterol/metabolismo , Fígado , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Camundongos , Ratos , Transdução de Sinais , Sirtuína 3/metabolismo , Ácido Úrico/análogos & derivados , beta Catenina/metabolismo
20.
J Mol Neurosci ; 72(8): 1706-1714, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35668313

RESUMO

LRP1, the low-density lipoprotein receptor 1, would be a novel candidate gene of epilepsy according to our bioinformatic results and the animal study. In this study, we explored the role of LRP1 in epilepsy and whether beta-hydroxybutyrate, the principal ketone body of the ketogenic diet, can treat epilepsy caused by LRP1 deficiency in drosophila. UAS/GAL4 system was used to establish different genotype models. Flies were given standard, high-sucrose, and ketone body food randomly. The bang-sensitive test was performed on flies and seizure-like behavior was assessed. In morphologic experiments, we found that LRP1 deficiency caused partial loss of the ellipsoidal body and partial destruction of the fan-shaped body. Whole-body and glia LRP1 defect flies had a higher seizure rate compared to the control group. Ketone body decreased the seizure rate in behavior test in all LRP1 defect flies, compared to standard and high sucrose diet. Overexpression of glutamate transporter gene Eaat1 could mimic the ketone body effect on LRP1 deficiency flies. This study demonstrated that LRP1 defect globally or in glial cells or neurons could induce epilepsy in drosophila. The ketone body efficaciously rescued epilepsy caused by LRP1 knockdown. The results support screening for LRP1 mutations as discriminating conduct for individuals who require clinical attention and further clarify the mechanism of the ketogenic diet in epilepsy, which could help epilepsy patients make a precise treatment case by case.


Assuntos
Drosophila , Epilepsia , Animais , Ácido Glutâmico , Corpos Cetônicos/uso terapêutico , Convulsões/tratamento farmacológico , Convulsões/genética , Sacarose
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