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1.
Proc Natl Acad Sci U S A ; 121(9): e2320276121, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38381789

RESUMO

Neuropeptide S (NPS) was postulated to be a wake-promoting neuropeptide with unknown mechanism, and a mutation in its receptor (NPSR1) causes the short sleep duration trait in humans. We investigated the role of different NPS+ nuclei in sleep/wake regulation. Loss-of-function and chemogenetic studies revealed that NPS+ neurons in the parabrachial nucleus (PB) are wake-promoting, whereas peri-locus coeruleus (peri-LC) NPS+ neurons are not important for sleep/wake modulation. Further, we found that a NPS+ nucleus in the central gray of the pons (CGPn) strongly promotes sleep. Fiber photometry recordings showed that NPS+ neurons are wake-active in the CGPn and wake/REM-sleep active in the PB and peri-LC. Blocking NPS-NPSR1 signaling or knockdown of Nps supported the function of the NPS-NPSR1 pathway in sleep/wake regulation. Together, these results reveal that NPS and NPS+ neurons play dichotomous roles in sleep/wake regulation at both the molecular and circuit levels.


Assuntos
Neuropeptídeos , Sono , Humanos , Sono/fisiologia , Ponte/fisiologia , Locus Cerúleo/fisiologia , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
2.
Cell Mol Neurobiol ; 43(7): 3251-3263, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37382853

RESUMO

The abnormal initiation of autophagy flux in neurons after ischemic stroke caused dysfunction of autophagy-lysosome, which not only led to autophagy flux blockage, but also resulted in autophagic death of neurons. However, the pathological mechanism of neuronal autophagy-lysosome dysfunction did not form a unified viewpoint until now. In this review, taking the autophagy lysosomal dysfunction of neurons as a starting point, we summarized the molecular mechanisms that led to neuronal autophagy lysosomal dysfunction after ischemic stroke, which would provide theoretical basis for the clinical treatment of ischemic stroke.


Assuntos
Autofagia , AVC Isquêmico , Lisossomos , AVC Isquêmico/metabolismo , AVC Isquêmico/patologia , AVC Isquêmico/terapia , Humanos , Animais , Neurônios/metabolismo , Neurônios/patologia , Lisossomos/patologia , Reperfusão , Proteínas do Tecido Nervoso/metabolismo
3.
Proc Natl Acad Sci U S A ; 116(24): 12045-12053, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31138685

RESUMO

Many components of the circadian molecular clock are conserved from flies to mammals; however, the role of mammalian Timeless remains ambiguous. Here, we report a mutation in the human TIMELESS (hTIM) gene that causes familial advanced sleep phase (FASP). Tim CRISPR mutant mice exhibit FASP with altered photic entrainment but normal circadian period. We demonstrate that the mutation prevents TIM accumulation in the nucleus and has altered affinity for CRY2, leading to destabilization of PER/CRY complex and a shortened period in nonmature mouse embryonic fibroblasts (MEFs). We conclude that TIM, when excluded from the nucleus, can destabilize the negative regulators of the circadian clock, alter light entrainment, and cause FASP.


Assuntos
Proteínas de Ciclo Celular/genética , Relógios Circadianos/genética , Ritmo Circadiano/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Mutação/genética , Sono/genética , Animais , Linhagem Celular , Fibroblastos/fisiologia , Células HEK293 , Humanos , Luz , Masculino , Camundongos , Camundongos Endogâmicos C57BL
4.
J Biol Chem ; 292(1): 161-171, 2017 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-27879317

RESUMO

Understanding the mechanism underlying the physiological divergence of species is a long-standing issue in evolutionary biology. The circadian clock is a highly conserved system existing in almost all organisms that regulates a wide range of physiological and behavioral events to adapt to the day-night cycle. Here, the interactions between hCK1ϵ/δ/DBT (Drosophila ortholog of CK1δ/ϵ) and serine-rich (SR) motifs from hPER2 (ortholog of Drosophila per) were reconstructed in a Drosophila circadian system. The results indicated that in Drosophila, the SR mutant form hPER2S662G does not recapitulate the mouse or human mutant phenotype. However, introducing hCK1δ (but not DBT) shortened the circadian period and restored the SR motif function. We found that hCK1δ is catalytically more efficient than DBT in phosphorylating the SR motif, which demonstrates that the evolution of CK1δ activity is required for SR motif modulation. Moreover, an abundance of phosphorylatable SR motifs and the striking emergence of putative SR motifs in vertebrate proteins were observed, which provides further evidence that the correlated evolution between kinase activity and its substrates set the stage for functional diversity in vertebrates. It is possible that such correlated evolution may serve as a biomarker associated with the adaptive benefits of diverse organisms. These results also provide a concrete example of how functional synthesis can be achieved through introducing evolutionary partners in vivo.


Assuntos
Proteínas CLOCK/metabolismo , Caseína Quinase 1 épsilon/metabolismo , Relógios Circadianos/fisiologia , Drosophila melanogaster/enzimologia , Evolução Molecular , Serina/metabolismo , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Humanos , Camundongos , Fenótipo , Fosforilação , Filogenia , Homologia de Sequência de Aminoácidos
5.
Nucleic Acids Res ; 42(16): 10278-87, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25122753

RESUMO

Circadian clocks allow organisms to orchestrate the daily rhythms in physiology and behaviors, and disruption of circadian rhythmicity can profoundly affect fitness. The mammalian circadian oscillator consists of a negative primary feedback loop and is associated with some 'auxiliary' loops. This raises the questions of how these interlocking loops coordinate to regulate the period and maintain its robustness. Here, we focused on the REV-ERBα/Cry1 auxiliary loop, consisting of Rev-Erbα/ROR-binding elements (RORE) mediated Cry1 transcription, coordinates with the negative primary feedback loop to modulate the mammalian circadian period. The silicon simulation revealed an unexpected rule: the intensity ratio of the primary loop to the auxiliary loop is inversely related to the period length, even when post-translational feedback is fixed. Then we measured the mRNA levels from two loops in 10-mutant mice and observed the similar monotonic relationship. Additionally, our simulation and the experimental results in human osteosarcoma cells suggest that a coupling effect between the numerator and denominator of this intensity ratio ensures the robustness of circadian period and, therefore, provides an efficient means of correcting circadian disorders. This ratio rule highlights the contribution of the transcriptional architecture to the period dynamics and might be helpful in the construction of synthetic oscillators.


Assuntos
Relógios Circadianos/genética , Regulação da Expressão Gênica , Fatores de Transcrição ARNTL/genética , Animais , Linhagem Celular Tumoral , Criptocromos/biossíntese , Criptocromos/genética , Retroalimentação Fisiológica , Humanos , Camundongos Knockout , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética , Proteínas Circadianas Period/genética , Transcrição Gênica
6.
Proc Natl Acad Sci U S A ; 110(12): 4750-5, 2013 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-23471982

RESUMO

The mammalian circadian clock is composed of interlocking feedback loops. Cryptochrome is a central component in the core negative feedback loop, whereas Rev-Erbα, a member of the nuclear receptor family, is an essential component of the interlocking loop. To understand the roles of different clock genes, we conducted a genetic interaction screen by generating single- and double-mutant mice. We found that the deletion of Rev-erbα in F-box/leucine rich-repeat protein (Fbxl3)-deficient mice rescued its long-circadian period phenotype, and our results further revealed that FBXL3 regulates Rev-Erb/retinoic acid receptor-related orphan receptor-binding element (RRE)-mediated transcription by inactivating the Rev-Erbα:histone deacetylase 3 corepressor complex. By analyzing the Fbxl3 and Cryptochrome 1 double-mutant mice, we found that FBXL3 also regulates the amplitudes of E-box-driven gene expression. These two separate roles of FBXL3 in circadian feedback loops provide a mechanism that contributes to the period determination and robustness of the clock.


Assuntos
Ritmo Circadiano/fisiologia , Criptocromos/metabolismo , Proteínas F-Box/metabolismo , Regulação da Expressão Gênica/fisiologia , Animais , Criptocromos/genética , Proteínas F-Box/genética , Produtos do Gene rev/genética , Produtos do Gene rev/metabolismo , Camundongos , Camundongos Knockout , Elementos de Resposta/fisiologia , Receptores alfa dos Hormônios Tireóideos/genética , Receptores alfa dos Hormônios Tireóideos/metabolismo
7.
EMBO J ; 29(8): 1389-400, 2010 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-20300063

RESUMO

The circadian clock has a central role in physiological adaption and anticipation of day/night changes. In a genetic screen for novel regulators of circadian rhythms, we found that mice lacking MAGED1 (Melanoma Antigen Family D1) exhibit a shortened period and altered rest-activity bouts. These circadian phenotypes are proposed to be caused by a direct effect on the core molecular clock network that reduces the robustness of the circadian clock. We provide in vitro and in vivo evidence indicating that MAGED1 binds to RORalpha to bring about positive and negative effects on core clock genes of Bmal1, Rev-erbalpha and E4bp4 expression through the Rev-Erbalpha/ROR responsive elements (RORE). Maged1 is a non-rhythmic gene that, by binding RORalpha in non-circadian way, enhances rhythmic input and buffers the circadian system from irrelevant, perturbing stimuli or noise. We have thus identified and defined a novel circadian regulator, Maged1, which is indispensable for the robustness of the circadian clock to better serve the organism.


Assuntos
Relógios Biológicos , Ritmo Circadiano , Proteínas de Neoplasias/metabolismo , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Animais , Linhagem Celular , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Atividade Motora , Células NIH 3T3 , Proteínas de Neoplasias/genética , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Ligação Proteica
8.
Optom Vis Sci ; 91(3): 272-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24509546

RESUMO

PURPOSE: Acinetobacter has low virulence but causes infections in subjects with reduced immunity. It has been reported in ocular infections including those of patients using contact lenses. Treatment is difficult because Acinetobacter is frequently multidrug resistant. Antibiotic-resistant strains frequently also harbor genes for antiseptic resistance (quaternary ammonium compound [QAC]) genes. Because Acinetobacter is part of the normal flora, it may contaminate contact lens and accessories. This study aims to investigate carriage rates of QAC genes in household and clinical isolates of Acinetobacter and to determine the effectiveness of two multipurpose solutions (MPSs) for soft lenses against organisms carrying QAC genes. METHODS: DNA was extracted from 11 bathroom isolates and 15 clinical isolates and amplified by polymerase chain reaction to determine the presence of qacEΔ1. Gene-positive and gene-negative control strains were used to challenge the two MPSs, and minimum inhibitory concentrations (MICs) of these organisms to benzalkonium chloride and chlorhexidine gluconate were determined. RESULTS: More than 90% of isolates carried qacEΔ1. The MICs of clinical isolates were higher than those of isolates of bathrooms. Both MPSs were able to produce a 3-log reduction in the numbers of all isolates. CONCLUSIONS: Although most isolates carried qacEΔ1 and elevated MICs to benzalkonium chloride and chlorhexidine gluconate were observed, all were susceptible to both MPSs tested. However, if there were to be poor compliance with care procedures, it is probable that such organisms could survive in the presence of diluted or expired solutions.


Assuntos
Acinetobacter/efeitos dos fármacos , Acinetobacter/genética , Anti-Infecciosos Locais/farmacologia , Compostos de Benzalcônio/farmacologia , Clorexidina/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Genes Bacterianos , Acinetobacter/isolamento & purificação , Proteínas de Bactérias/genética , Lentes de Contato Hidrofílicas/microbiologia , DNA Bacteriano/análise , Humanos , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase
9.
Hepatology ; 54(4): 1410-20, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21725993

RESUMO

UNLABELLED: Many aspects of energy metabolism, including glucose and lipid homeostasis and mitochondrial oxidative metabolism, are under precise control by the mammalian circadian clock. However, the molecular mechanism for coordinate integration of the circadian clock and various metabolic pathways is poorly understood. Here we show that BAF60a, a chromatin-remodeling complex subunit, is rhythmically expressed in the liver of mice. Mice with liver-specific knockdown of BAF60a show abnormalities in the rhythmic expression pattern of clock and metabolic genes and in the circulating metabolite profile. Consistently, knockdown of BAF60a impairs the oscillation of clock genes in serum-shocked HepG(2) cells. At the molecular level, BAF60a activates Bmal1 and G6Pase transcription by way of the coactivation of retinoid-related orphan receptor alpha (RORα). In addition, BAF60a is present near ROR response elements (RORE) on the proximal Bmal1 and G6Pase promoters and turns the chromatin structure into the active state. CONCLUSION: Our data suggest a critical role for BAF60a in the coordinated regulation of hepatic circadian clock and energy metabolism in mammals.


Assuntos
Relógios Circadianos/genética , Proteínas de Ligação a DNA/metabolismo , Metabolismo Energético/genética , Glucose-6-Fosfatase/metabolismo , Fatores de Transcrição/metabolismo , Animais , Imunoprecipitação da Cromatina , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica , Glucose-6-Fosfatase/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/metabolismo , Distribuição Aleatória , Reação em Cadeia da Polimerase em Tempo Real , Valores de Referência , Sacarose/metabolismo , Técnicas de Cultura de Tecidos , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética
10.
Optom Vis Sci ; 89(7): E1030-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22729171

RESUMO

PURPOSE: To compare the rates of bacterial contamination in cylindrical and flat contact lens cases of orthokeratology (ortho-k) users and to investigate their preference of lens case design based on ease of use and handling. METHODS: Twenty-four children receiving ortho-k treatment were recruited. Each subject was given one cylindrical and one flat lens case, of which one side (50% right, 50% left) was sealed to prevent usage. Subjects were instructed to either rinse the case with water and air dry or rinse with multipurpose solution (MPS) and refill with MPS for storage after lens removal. After 1 month, cases were collected for culture, which was performed on the screw top, inner surface of cases, and also the holder for cylindrical cases. Each subject/parent completed a questionnaire about preference of case design. RESULTS: No significant differences in rates of surfaces contaminated were found between cleaning methods. Overall, 30% of both inner surfaces and screw tops of the cases yielded potentially pathogenic organisms, with significantly higher numbers present on both the inner surfaces (p = 0.003) and the screw tops of the flat cases (p = 0.001). Contamination of the inner surfaces with only normal flora occurred exclusively in the flat cases, but the screw tops of both case types frequently yielded only normal flora. Cylindrical case holder contamination was similar to the inner surface. There was a strong preference (75%) for the cylindrical cases, with subjects/parents citing ease of use and cleaning, good appearance and transparency, and reduced amount of MPS used. CONCLUSIONS: Although correct lens case care remains the most important factor in reducing contamination of the case, use of the cylindrical case design, preferred by the majority of subjects/parents, significantly reduced contamination in ortho-k subjects. The method used for cleaning the lens case had no effect on the rates of contamination in this study.


Assuntos
Soluções para Lentes de Contato/efeitos adversos , Lentes de Contato/microbiologia , Contaminação de Equipamentos/estatística & dados numéricos , Bactérias/isolamento & purificação , Criança , Desinfecção/métodos , Contaminação de Equipamentos/prevenção & controle , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Inquéritos e Questionários
11.
Optom Vis Sci ; 89(1): 44-51, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22127149

RESUMO

PURPOSE: To compare the traditional manual hemacytometer method and an automated counter (Vi-cell) to enumerate and distinguish between viable and non-viable amoeba, and to determine the efficacies of contact lens (CL) disinfecting solutions against three species of Acanthamoeba. The efficacies in the presence of a bacterial food source and bovine serum albumin (BSA) were investigated. METHODS: Four brands of multipurpose solutions and a hydrogen peroxide disinfecting system (Oxysept) for soft CLs, and four disinfecting solutions for Rigid Gas Permeable (RGP) lenses were tested against three species of Acanthamoeba. Page's amoebic saline was included as a negative control and standard solutions of disinfecting agents, 6% hydrogen peroxide and 0.5% chlorhexidine, as positive controls. The effects of the presence of Pseudomonas aeruginosa and BSA on effectiveness were assessed. RESULTS: None of the CL solutions tested achieved a 1-log reduction in viability of all three Acanthamoeba species within the manufacturer's recommended disinfection times. The presence of P. aeruginosa did not significantly affect disinfecting capacity of multipurpose solution solutions but reduced activity of RGP solutions and the hydrogen peroxide system. BSA reduced trophozoicidal activity of all solutions. Bland and Altman analysis showed good agreement between Vi-cell and hemacytometer. CONCLUSIONS: The Vi-Cell analyzer offers a simple and effective method of determining amoebicidal activity. Our results show that the CL solutions tested could not satisfactorily kill Acanthamoeba.


Assuntos
Ceratite por Acanthamoeba/prevenção & controle , Acanthamoeba/efeitos dos fármacos , Amebicidas/farmacologia , Soluções para Lentes de Contato/farmacologia , Lentes de Contato Hidrofílicas/parasitologia , Desinfetantes/farmacologia , Desinfecção/métodos , Acanthamoeba/isolamento & purificação , Ceratite por Acanthamoeba/parasitologia , Animais , Humanos
12.
Optom Vis Sci ; 88(6): 703-7, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21460755

RESUMO

PURPOSE: To compare the effects of drying the lens case with tissue on the presence of Acanthamoeba with cases left wet and to determine adherence to the lens case of varying concentrations of Acanthamoeba suspensions. The effect of drying on viability of Acanthamoeba in new, used, and soiled lens cases was compared over a 24 h period. METHODS: New (16) and scratched (16) lens cases were rinsed with a range of Acanthamoeba suspensions. Eight of each group were dried with tissue and the presence of Acanthamoeba was determined in all cases using polymerase chain reaction. To examine effects of drying, forty-two lens case wells were scratched to simulate use and 21 of these were artificially soiled with serum Bovine albumin. These cases and a further 21 unused wells were contaminated with Acanthamoeba (×10/ml) and then left to dry in a cool, dry environment. Three wells of each group were sampled at time 0, 2, 4, 6, 8, 12, and 24 h, and the number of viable Acanthamoeba were determined. RESULTS: Acanthamoeba were more likely to adhere to used than unused lens cases (p < 0.05). Detection of Acanthamoeba in wiped lens cases was at 2-log dilutions less than in cases left wet for both new and used lens cases. Adherence were significantly different between rinse and rinse/dried cases (p = 0.015). Air drying significantly reduced the numbers of viable amoebic cysts and trophozoites and the effect was time dependent. Survival was significantly higher in used and soiled wells. CONCLUSIONS: Drying with tissue after rinsing significantly reduces numbers of adhering Acanthamoeba. Acanthamoeba were found to be able to adhere even to new unused cases, so the importance of proper cleaning and disinfection of lens cases cannot be underestimated. Air drying reduces viability but some viable cells were present at 24 h in soiled cases, confirming the role of biofilm in protecting organisms from desiccation.


Assuntos
Acanthamoeba/efeitos dos fármacos , Lentes de Contato , Dessecação , Contaminação de Equipamentos , Água/farmacologia , Acanthamoeba/fisiologia , Biofilmes , Adesão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Soroalbumina Bovina , Fatores de Tempo
13.
Curr Biol ; 31(1): 13-24.e4, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33065013

RESUMO

Sufficient and efficient sleep is crucial for our health. Natural short sleepers can sleep significantly shorter than the average population without a desire for more sleep and without any obvious negative health consequences. In searching for genetic variants underlying the short sleep trait, we found two different mutations in the same gene (metabotropic glutamate receptor 1) from two independent natural short sleep families. In vitro, both of the mutations exhibited loss of function in receptor-mediated signaling. In vivo, the mice carrying the individual mutations both demonstrated short sleep behavior. In brain slices, both of the mutations changed the electrical properties and increased excitatory synaptic transmission. These results highlight the important role of metabotropic glutamate receptor 1 in modulating sleep duration.


Assuntos
Receptores de Glutamato Metabotrópico/genética , Sono/genética , Animais , Análise Mutacional de DNA , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Hipocampo/fisiologia , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Modelos Animais , Mutação , Plasticidade Neuronal/fisiologia , Técnicas de Patch-Clamp , Linhagem , Polissonografia , Receptores de Glutamato Metabotrópico/metabolismo , Fatores de Tempo , Sequenciamento do Exoma
14.
Curr Eye Res ; 45(5): 550-555, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31697186

RESUMO

Purpose: This study aimed to evaluate the microbial contamination level and its influencing factors of rigid gas permeable (RGP) trial lenses and lens cases in China.Materials and Methods: A total of 107 RGP trial lenses and lens cases were collected from 7 main hospitals or optometric centers in China. Three sites including the lenses, case interiors and case screw tops were sampled for bacterial and fungal culture and identification. The contamination rates of these three sites and their relationship with lens care regimes were further analyzed.Results: The overall contamination rate was 73.8% for either lenses or cases, and 43.0% of lenses, 57.0% of case interiors and 65.4% of case screw tops respectively. The most frequently isolated microorganisms were Serratia spp., Burkholderia spp., Pandoraea spp., and Achromobacter spp. from all three sites. The contamination rate was positively related to the lens use frequency. Compared with dry-stored lenses, the contamination rate was significantly higher in wet-stored group (P < .001*). Inadequate disinfection and improper lens and case care regimes were also associated with higher contamination rates.Conclusions: Our study reported that the RGP trial lenses and cases used for fittings had a considerably high contamination rate. The safe use of RGP trial lenses and education of optometrists on the regular maintenance of trial lenses should be emphasized.


Assuntos
Bactérias/isolamento & purificação , Lentes de Contato/microbiologia , Contaminação de Equipamentos/estatística & dados numéricos , Equipamentos e Provisões/microbiologia , Fungos/isolamento & purificação , Adulto , Técnicas Bacteriológicas , China/epidemiologia , Soluções para Lentes de Contato , Feminino , Humanos , Masculino , Pirrolidinas/normas , Adulto Jovem
15.
J Orthop Translat ; 24: 112-120, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32775203

RESUMO

BACKGROUND/OBJECTIVES: For treatment of large bone defects challenging in orthopaedic clinics, bone graft substitutes are commonly used for the majority of surgeons. It would be proposed in the current study that our bioactive scaffolds could additionally serve as a local delivery system for therapeutic small molecule agents capable of providing support to enhance biological bone repair. METHODS: In this study, composite scaffolds made of poly (lactic-co-glycolic acid) (PLGA) and tricalcium phosphate (TCP) named by P/T was fabricated by a low-temperature rapid prototyping technique. For optimizing the scaffolds, the phytomolecule icaritin (ICT) was incorporated into P/T scaffolds called P/T/ICT. The osteogenic efficacies of the two groups of scaffolds were compared in a successfully established calvarial defect model in rats. Bone regeneration was evaluated by X-ray, micro-computerised tomography (micro-CT), and histology at weeks 4 and/or 8 post-implantation. In vitro induction of osteogenesis and osteoclastogenesis was established for identification of differentiation potentials evoked by icaritin in primary cultured precursor cells. RESULTS: The results of radiographies and decalcified histology demonstrated more area and volume fractions of newly formed bone within bone defect sites implanted with P/T/ICT scaffold than that with P/T scaffold. Undecalcified histological results presented more osteoid and mineralized bone tissues, and also more active bone remodeling in P/T/ICT group than that in P/T group. The results of histological staining in osteoclast-like cells and newly formed vessels indicated favorable biocompatibility, rapid bioresorption and more new vessel growth in P/T/ICT scaffolds in contrast to P/T scaffolds. Based on in vitro induction, the results presented that icaritin could significantly facilitate osteogenic differentiation, while suppressed adipogenic differentiation. Meanwhile, icaritin demonstrated remarkable inhibition of osteoclastogenic differentiation. CONCLUSION: The finding that P/T/ICT composite scaffold can enhance bone regeneration in calvarial bone defects through facilitating effective bone formation and restraining excessive bone resorption. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: The osteogenic bioactivity of icaritin facilitated PLGA/TCP/icartin composite scaffold to exert significant bone regeneration in calvarial defects in rat model. It might form an optimized foundation for potential clinical validation in bone defects application.

16.
Sci Transl Med ; 11(514)2019 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619542

RESUMO

Sleep is a crucial physiological process for our survival and cognitive performance, yet the factors controlling human sleep regulation remain poorly understood. Here, we identified a missense mutation in a G protein-coupled neuropeptide S receptor 1 (NPSR1) that is associated with a natural short sleep phenotype in humans. Mice carrying the homologous mutation exhibited less sleep time despite increased sleep pressure. These animals were also resistant to contextual memory deficits associated with sleep deprivation. In vivo, the mutant receptors showed increased sensitivity to neuropeptide S exogenous activation. These results suggest that the NPS/NPSR1 pathway might play a critical role in regulating human sleep duration and in the link between sleep homeostasis and memory consolidation.


Assuntos
Consolidação da Memória/fisiologia , Receptores Acoplados a Proteínas G/metabolismo , Sono/fisiologia , Animais , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Mutação/genética , Reação em Cadeia da Polimerase , Reação em Cadeia da Polimerase em Tempo Real , Receptores Acoplados a Proteínas G/genética , Sono/genética
17.
Neuron ; 103(6): 1044-1055.e7, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31473062

RESUMO

Sleep is crucial for our survival, and many diseases are linked to long-term poor sleep quality. Before we can use sleep to enhance our health and performance and alleviate diseases associated with poor sleep, a greater understanding of sleep regulation is necessary. We have identified a mutation in the ß1-adrenergic receptor gene in humans who require fewer hours of sleep than most. In vitro, this mutation leads to decreased protein stability and dampened signaling in response to agonist treatment. In vivo, the mice carrying the same mutation demonstrated short sleep behavior. We found that this receptor is highly expressed in the dorsal pons and that these ADRB1+ neurons are active during rapid eye movement (REM) sleep and wakefulness. Activating these neurons can lead to wakefulness, and the activity of these neurons is affected by the mutation. These results highlight the important role of ß1-adrenergic receptors in sleep/wake regulation.


Assuntos
Receptores Adrenérgicos beta 1/genética , Sono/genética , Vigília/genética , Animais , Técnicas de Introdução de Genes , Humanos , Camundongos , Mutação , Neurônios/metabolismo , Linhagem , Tegmento Pontino/citologia , Tegmento Pontino/metabolismo , Transtornos do Sono-Vigília/genética , Sono REM/genética
18.
Curr Eye Res ; 43(2): 200-207, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29135319

RESUMO

PURPOSE: Scleral remodeling causes the excessive ocular elongation that underlies myopia. Lysyl oxidase (LOX), a copper-containing amine oxidase, can catalyze collagen and elastin crosslinking. The purpose of this study was to investigate the role of LOX in scleral remodeling in form-deprivation myopia (FDM). METHODS: Seventy-five guinea pigs were randomly divided into five groups as follows: a normal control group, an FDM group, an FDM plus ß-aminopropionitrile (BAPN) group, an FDM plus TGF-ß1 (TGF-ß1) group, and an FDM plus vehicle group. A translucent diffuser was used to induce FDM, and intravitreal injection was used to administer BAPN, TGF-ß1 or vehicle. The scleral LOX and collagen gene and protein levels and the posterior scleral ultrastructure and biomechanics were measured. RESULTS: In the FDM group, both the scleral LOX and collagen gene and protein levels were significantly lower than those in the control eyes. The collagen fibril diameters were significantly decreased in the FDM group compared with the diameters in the control group. A significant decrease in LOX gene and protein expression was observed after BAPN injection, and an increase was observed after TGF-ß1 treatment compared with the levels in the FDM group. Additionally, the scleral collagen fibrils were significantly decreased in the BAPN-treated eyes but increased in the TGF-ß1-treated eyes compared with the FDM eyes. The ultimate stress and Young's modulus of the sclera were lowest in the BAPN group, followed by the FDM group and the TGF-ß1 group. The ultimate strain (%) of the sclera was lowest in the TGF-ß1 group, followed by the FDM group and the BAPN group. CONCLUSION: LOX expression was significantly lowered in myopic sclera. Modulating LOX expression induced a change in both the scleral collagen fibril diameter and the scleral biomechanics. Therefore, LOX may play a key role in the myopia scleral remodeling procedure.


Assuntos
Colágeno Tipo I/metabolismo , Regulação da Expressão Gênica/fisiologia , Miopia/enzimologia , Proteína-Lisina 6-Oxidase/genética , Proteína-Lisina 6-Oxidase/metabolismo , Esclera/fisiologia , Aminopropionitrilo/farmacologia , Animais , Fenômenos Biomecânicos , Western Blotting , Colágeno Tipo I/genética , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Cobaias , Microscopia Eletrônica de Transmissão , Miopia/fisiopatologia , Proteína-Lisina 6-Oxidase/antagonistas & inibidores , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Esclera/ultraestrutura , Privação Sensorial , Fator de Crescimento Transformador beta1/farmacologia
19.
Curr Opin Neurobiol ; 44: 43-49, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28325617

RESUMO

Why we sleep remains one of the greatest mysteries in science. In the past few years, great advances have been made to better understand this phenomenon. Human genetics has contributed significantly to this movement, as many features of sleep have been found to be heritable. Discoveries about these genetic variations that affect human sleep will aid us in understanding the underlying mechanism of sleep. Here we summarize recent discoveries about the genetic variations affecting the timing of sleep, duration of sleep and EEG patterns. To conclude, we also discuss some of the sleep-related neurological disorders such as Autism Spectrum Disorder (ASD) and Alzheimer's Disease (AD) and the potential challenges and future directions of human genetics in sleep research.


Assuntos
Variação Genética , Sono/genética , Eletroencefalografia , Genética Médica/tendências , Humanos , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/fisiopatologia , Pesquisa/tendências , Tempo
20.
Biomed Res Int ; 2017: 3703854, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28845432

RESUMO

PURPOSE: To investigate the interaction between corneal, internal, and total wavefront aberrations (WAs) and their influential factors during orthokeratology (OK) treatment in Chinese adolescents. METHODS: Thirty teenagers (n = 30 eyes) were enrolled in the study; spherical equivalent refraction (SE), corneal curvature radius (CCR), central corneal thickness (CCT), WAs, and the difference in limbal transverse diameter and OK lens diameter (ΔLLD) were detected before and after one-month OK treatment. Every component of WAs was measured simultaneously by iTrace aberrometer. The influential factors of OK-induced WAs were analyzed. RESULTS: SE and CCT decreased while CCR increased significantly (P < 0.01). Higher-order aberrations (HOAs), Spherical aberrations (SAs), and coma increased significantly (P < 0.01). Corneal horizontal coma (Z31-C) and corneal spherical aberrations (Z40-C) increased (P < 0.01). The HOAs, coma, SAs, Z31-C, Z31-T, Z40-C, and Z40-T were positively correlated with SE and CCR (P < 0.01). Z3-1-C showed negative correlations with (ΔLLD) and positive correlations with SE (P < 0.05). CONCLUSIONS: The increase in OK-induced HOAs is mainly attributed to Z31 and Z40 of cornea. Z3-1 in the internal component showed a compensative effect on the corneal vertical coma. The degree of myopic correction and increase in CCR may be the essential influential factors of the increase in Z31 and Z40. The appropriate size of the OK lens may be helpful to decrease OK-induced vertical coma.


Assuntos
Córnea/cirurgia , Topografia da Córnea/estatística & dados numéricos , Aberrações de Frente de Onda da Córnea , Procedimentos Ortoceratológicos , Adolescente , Criança , Estudos de Coortes , Aberrações de Frente de Onda da Córnea/diagnóstico , Aberrações de Frente de Onda da Córnea/etiologia , Feminino , Humanos , Masculino , Procedimentos Ortoceratológicos/efeitos adversos , Procedimentos Ortoceratológicos/estatística & dados numéricos
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