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1.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33753498

RESUMO

The homeostasis of protein palmitoylation and depalmitoylation is essential for proper physiological functions in various tissues, in particular the central nervous system (CNS). The dysfunction of PPT1 (PPT1-KI, infantile neuronal ceroid lipofuscinosis [INCL] mouse model), which catalyze the depalmitoylation process, results in serious neurodegeneration accompanied by severe astrogliosis in the brain. Endeavoring to determine critical factors that might account for the pathogenesis in CNS by palm-proteomics, glial fibrillary acidic protein (GFAP) was spotted, indicating that GFAP is probably palmitoylated. Questions concerning if GFAP is indeed palmitoylated in vivo and how palmitoylation of GFAP might participate in neural pathology remain unexplored and are waiting to be investigated. Here we show that GFAP is readily palmitoylated in vitro and in vivo; specifically, cysteine-291 is the unique palmitoylated residue in GFAP. Interestingly, it was found that palmitoylated GFAP promotes astrocyte proliferation in vitro. Furthermore, we showed that PPT1 depalmitoylates GFAP, and the level of palmitoylated GFAP is overwhelmingly up-regulated in PPT1-knockin mice, which lead us to speculate that the elevated level of palmitoylated GFAP might accelerate astrocyte proliferation in vivo and ultimately led to astrogliosis in INCL. Indeed, blocking palmitoylation by mutating cysteine-291 into alanine in GFAP attenuate astrogliosis, and remarkably, the concurrent neurodegenerative pathology in PPT1-knockin mice. Together, these findings demonstrate that hyperpalmitoylated GFAP plays critical roles in regulating the pathogenesis of astrogliosis and neurodegeneration in the CNS, and most importantly, pinpointing that cysteine-291 in GFAP might be a valuable pharmaceutical target for treating INCL and other potential neurodegenerative diseases.


Assuntos
Astrócitos/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/metabolismo , Lipofuscinoses Ceroides Neuronais/metabolismo , Tioléster Hidrolases/genética , Animais , Astrócitos/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Técnicas de Introdução de Genes , Técnicas de Inativação de Genes , Proteína Glial Fibrilar Ácida/genética , Gliose/genética , Humanos , Lipoilação , Camundongos , Camundongos Endogâmicos C57BL , Lipofuscinoses Ceroides Neuronais/genética
2.
Environ Monit Assess ; 193(8): 483, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34241745

RESUMO

This work investigated heavy metal and cyanide pollution in surface soils and edible plants around Yanzhuang gold tailings ponds in the region of Yanzhuang Village in Pinggu District, Beijing. Surface soil samples were collected from 33 sites around gold tailings ponds, and concentrations of seven heavy metals (i.e., Sb, As, Cd, Cu, Pb, Zn, and Hg) and cyanide were analyzed to determine their spatial distributions, pollution degrees, and sources. The potential ecological risks of As, Cd, Cu, Pb, Zn, and Hg were preliminarily assessed. The results showed that the mean cyanide, Sb, As, Cd, Cu, and Pb concentrations were higher than the standard values. The pollutant concentrations around the tailings ponds were high and decreased with increasing distance from the ponds. The single pollution index indicated that cyanide, As, and Cd were the main pollutants. The Nemerow pollution index revealed a large region and serious degree of heavy metal pollution in soils. The potential ecological risk level of the study area was moderate, with Cd and As posing the main risks. Multivariate statistical analysis suggested that the heavy metal and cyanide pollution present mainly derived from gold tailings, with agricultural pollution also had a certain effect. However, the 12 edible plants sampled were basically not polluted.


Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes do Solo , Pequim , China , Monitoramento Ambiental , Ouro , Metais Pesados/análise , Lagoas , Medição de Risco , Solo , Poluentes do Solo/análise
3.
Pharmacol Res ; 152: 104618, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31891789

RESUMO

Several decades have passed since resveratrol (RSV) was first identified in red wine. Researchers have reported the pleiotropic anti-oxidant, anti-inflammatory, anti-cancer, anti-aging, and neuronal protective effects of resveratrol and its glycosylated derivative. However, few studies have distinguished the minute differences in the properties between resveratrol and its glycosylated derivative in terms of synaptic plasticity. As an abundant natural product of glycosylated resveratrol, the derivative 2,3,4',5-tetrahydroxystilbene-2-O-ß-d-glucoside (TSG) has been determined to be a better option for long-term potentiation (LTP) in the hippocampus under physiological and pathological conditions than resveratrol. TSG, as well as its parent molecule RSV, could elicit early-LTP and recover fast excitatory postsynaptic potentials (EPSPs) in the hippocampus. Using various modalities, including pre- and post-whole-cell patch clamping techniques in the calyx of Held, pharmacological inhibition of the N-methyl-d-aspartic acid receptor (NMDAr) and the α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor (AMPAr) as well as protein kinase C (PKC) activation, we demonstrated that TSG, unlike RSV, could merely promote NMDA-mediated EPSC via PKCß cascade. Our results provide new knowledge that glycosylation of resveratrol could significantly improve its specificity in promoting sole NMDAr mediation of EPSPs, in addition to improving solubility and resistance against oxidation in vivo. These observations could contribute to further exploration of pharmaceutical evaluation of glycosylated stilbene in the future.


Assuntos
Glucosídeos/farmacologia , Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Hipocampo/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteína Quinase C beta/fisiologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/fisiologia
4.
J Cell Mol Med ; 23(9): 6512-6518, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31270934

RESUMO

Genome-wide association studies have confirmed that schizophrenia is an inheritable multiple-gene mental disorder. Longitudinal studies about depression, first episode psychosis (FEP) and acute psychotic relapse have mostly searched for brain imaging biomarkers and inflammatory markers from the blood. However, to the best of our knowledge, the association between enzymatic activities with diagnosis or prediction of treatment response in people with schizophrenia has barely been validated. Under the Longitudinal Study of National Mental Health Work Plan (2015-2020), we have studied a subsample of approximately 36 individuals from the cohort with data on palmitoyl-protein thioesterase-1 enzymatic activity from FEP and performed a bivariate correlation analysis with psychiatric assessment scores. After adjusting for sex, age, body mass index (BMI) and total serum protein, our data demonstrated that PPT1 enzymatic activity is significantly associated with schizophrenia and its Positive and Negative Syndrome Scale (PANSS) scores. This longitudinal study compared the PPT1 enzymatic activity in FEP schizophrenia patients and healthy volunteers, and the former exhibited a significant 1.5-fold increase in PPT1 enzymatic levels (1.79 mmol/L/h/mL, and 1.18 mmol/L/h/mL; P < 0.05; 95% CI, 2.3-2.9 and 1.4-1.8). The higher PPT1 enzymatic levels in FEP schizophrenia patients were positively associated with larger PANSS scaling scores (r = 0.32, P = 0.0079 for positive scaling; r = 0.41, P = 0.0006 for negative scaling; r = 0.45, P = 0.0001 for general scaling; and r = 0.34, P = 0.0048 for PNASS-S scaling). Higher enzymatic PPT1 in FEP schizophrenia patients is significantly associated with increased PANSS scaling values, indicating more serious rates of developing psychosis. Enzymatic activity of PPT1 may provide an important new view for schizophrenia disorders.


Assuntos
Esquizofrenia/sangue , Esquizofrenia/metabolismo , Tioléster Hidrolases/sangue , Tioléster Hidrolases/metabolismo , Adolescente , Adulto , Biomarcadores/sangue , Biomarcadores/metabolismo , Estudos de Coortes , Depressão/sangue , Depressão/metabolismo , Feminino , Estudo de Associação Genômica Ampla , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/sangue , Transtornos Psicóticos/metabolismo , Adulto Jovem
5.
Hum Mol Genet ; 24(19): 5416-32, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26160911

RESUMO

Neurodegeneration is a devastating manifestation in the majority of >50 lysosomal storage disorders (LSDs). Neuronal ceroid lipofuscinoses (NCLs) are the most common childhood neurodegenerative LSDs. Mutations in 13 different genes (called CLNs) underlie various types of NCLs, of which the infantile NCL (INCL) and congenital NCL (CNCL) are the most lethal. Although inactivating mutations in the CLN1 gene encoding palmitoyl-protein thioesterase-1 (PPT1) cause INCL, those in the CLN10 gene encoding cathepsin D (CD) underlie CNCL. PPT1 is a lysosomal thioesterase that cleaves the thioester linkage in S-acylated proteins required for their degradation by lysosomal hydrolases like CD. Thus, PPT1 deficiency causes lysosomal accumulation of these lipidated proteins (major constituents of ceroid) leading to INCL. We sought to determine whether there is a common pathogenic link between INCL and CNCL. Using biochemical, histological and confocal microscopic analyses of brain tissues and cells from Cln1(-/-) mice that mimic INCL, we uncovered that Cln10/CD is overexpressed. Although synthesized in the endoplasmic reticulum, the CD-precursor protein (pro-CD) is transported through endosome to the lysosome where it is proteolytically processed to enzymatically active-CD. We found that despite Cln10 overexpression, the maturation of pro-CD to enzymatically active-CD in lysosome was disrupted. This defect impaired lysosomal degradative function causing accumulation of undegraded cargo in lysosome leading to INCL. Notably, treatment of intact Cln1(-/-) mice as well as cultured brain cells derived from these animals with a thioesterase-mimetic small molecule, N-tert-butyl-hydroxylamine, ameliorated the CD-processing defect. Our findings are significant in that they define a pathway in which Cln1 mutations disrupt the maturation of a major degradative enzyme in lysosome contributing to neuropathology in INCL and suggest that lysosomal CD deficiency is a common pathogenic link between INCL and CNCL.


Assuntos
Encéfalo/metabolismo , Catepsina D/metabolismo , Lipofuscinoses Ceroides Neuronais/patologia , Tioléster Hidrolases/genética , Animais , Encéfalo/patologia , Catepsina D/deficiência , Criança , Modelos Animais de Doenças , Regulação da Expressão Gênica , Humanos , Hidroxilaminas/administração & dosagem , Hidroxilaminas/uso terapêutico , Lisossomos/metabolismo , Camundongos , Mutação , Lipofuscinoses Ceroides Neuronais/tratamento farmacológico , Lipofuscinoses Ceroides Neuronais/genética
6.
Nano Lett ; 15(7): 4303-10, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-26053999

RESUMO

We report tip-enhanced and conventional Raman spectroscopy studies of Ge-Si0.5Ge0.5 core-shell nanowires in which we observe two distinct Ge-Ge vibrational mode Raman peaks associated with vibrations in the Ge nanowire core and at the Ge-Si0.5Ge0.5 interface at which a quantum-confined hole gas is formed. Tip enhanced Raman measurements show dramatically increased sensitivity to the modes at the Ge-Si0.5Ge0.5 interface and a shift in position of this mode due to plasmonic field localization at the tip apex and the resulting change in phonon self-energy caused by increased coupling between phonons and intervalence-band carrier transitions.

7.
J Biol Chem ; 288(13): 9112-25, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23396970

RESUMO

Acyl-protein thioesterase-1 (APT1) and APT2 are cytosolic enzymes that catalyze depalmitoylation of membrane-anchored, palmitoylated H-Ras and growth-associated protein-43 (GAP-43), respectively. However, the mechanism(s) of cytosol-membrane shuttling of APT1 and APT2, required for depalmitoylating their substrates H-Ras and GAP-43, respectively, remained largely unknown. Here, we report that both APT1 and APT2 undergo palmitoylation on Cys-2. Moreover, blocking palmitoylation adversely affects membrane localization of both APT1 and APT2 and that of their substrates. We also demonstrate that APT1 not only catalyzes its own depalmitoylation but also that of APT2 promoting dynamic palmitoylation (palmitoylation-depalmitoylation) of both thioesterases. Furthermore, shRNA suppression of APT1 expression or inhibition of its thioesterase activity by palmostatin B markedly increased membrane localization of APT2, and shRNA suppression of APT2 had virtually no effect on membrane localization of APT1. In addition, mutagenesis of the active site Ser residue to Ala (S119A), which renders catalytic inactivation of APT1, also increased its membrane localization. Taken together, our findings provide insight into a novel mechanism by which dynamic palmitoylation links cytosol-membrane trafficking of APT1 and APT2 with that of their substrates, facilitating steady-state membrane localization and function of both.


Assuntos
Citosol/metabolismo , Proteína GAP-43/metabolismo , Tioléster Hidrolases/metabolismo , Proteínas ras/metabolismo , Animais , Astrócitos/citologia , Domínio Catalítico , Membrana Celular/metabolismo , Células Cultivadas , Humanos , Camundongos , Microscopia Confocal , Mutagênese , Mutação , Células NIH 3T3 , Neurônios/metabolismo , Ácido Palmítico/química , Ácido Palmítico/metabolismo , Ligação Proteica , Proto-Oncogene Mas , Frações Subcelulares/metabolismo , Transfecção
8.
Hum Mol Genet ; 21(10): 2233-44, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22331300

RESUMO

Disruption of the blood-brain barrier (BBB) is a serious complication frequently encountered in neurodegenerative disorders. Infantile neuronal ceroid lipofuscinosis (INCL) is a devastating childhood neurodegenerative lysosomal storage disorder caused by palmitoyl-protein thioesterase-1 (PPT1) deficiency. It remains unclear whether BBB is disrupted in INCL and if so, what might be the molecular mechanism(s) of this complication. We previously reported that the Ppt1-knockout (Ppt1-KO) mice that mimic INCL manifest high levels of oxidative stress and neuroinflammation. Recently, it has been reported that CD4(+) T-helper 17 (T(H)17) lymphocytes may mediate BBB disruption and neuroinflammation, although the precise molecular mechanism(s) remain unclear. We sought to determine: (i) whether the BBB is disrupted in Ppt1-KO mice, (ii) if so, do T(H)17-lymphocytes underlie this complication, and (iii) how might T(H)17 lymphocytes breach the BBB. Here, we report that the BBB is disrupted in Ppt1-KO mice and that T(H)17 lymphocytes producing IL-17A mediate disruption of the BBB by stimulating production of matrix metalloproteinases (MMPs), which degrade the tight junction proteins essential for maintaining BBB integrity. Importantly, dietary supplementation of resveratrol (RSV), a naturally occurring antioxidant/anti-inflammatory polyphenol, markedly reduced the levels of T(H)17 cells, IL-17A and MMPs, and elevated the levels of tight junction proteins, which improved the BBB integrity in Ppt1-KO mice. Intriguingly, we found that RSV suppressed the differentiation of CD4(+) T lymphocytes to IL-17A-positive T(H)17 cells. Our findings uncover a mechanism by which T(H)17 lymphocytes mediate BBB disruption and suggest that small molecules such as RSV that suppress T(H)17 differentiation are therapeutic targets for neurodegenerative disorders such as INCL.


Assuntos
Barreira Hematoencefálica/metabolismo , Inibidores Enzimáticos/farmacologia , Camundongos , Lipofuscinoses Ceroides Neuronais/metabolismo , Estilbenos/farmacologia , Tioléster Hidrolases/genética , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Camundongos Knockout , Lipofuscinoses Ceroides Neuronais/enzimologia , Resveratrol , Tioléster Hidrolases/metabolismo
9.
Sci Rep ; 14(1): 9439, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658603

RESUMO

This paper optimizes the 2D Wadell roundness calculation of particles based on digital image processing methods. An algorithm for grouping corner key points is proposed to distinguish each independent corner. Additionally, the cyclic midpoint filtering method is introduced for corner dealiasing, aiming to mitigate aliasing issues effectively. The relationships between the number of corner pixels (m), the central angle of the corner (α) and the parameter of the dealiasing degree (n) are established. The Krumbein chart and a sandstone thin section image were used as examples to calculate the 2D Wadell roundness. A set of regular shapes is calculated, and the error of this method is discussed. When α ≥ 30°, the maximum error of Wadell roundness for regular shapes is 5.21%; when 12° ≤ α < 30°, the maximum error increases. By applying interpolation to increase the corner pixels to the minimum number (m0) within the allowable range of error, based on the α-m0 relational expression obtained in this study, the error of the corner circle can be minimized. The results indicate that as the value of m increases, the optimal range interval for n also widens. Additionally, a higher value of α leads to a lower dependence on m. The study's results can be applied to dealiasing and shape analysis of complex closed contours.

10.
Hum Mol Genet ; 20(6): 1111-21, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21224254

RESUMO

The infantile neuronal ceroid lipofuscinosis (INCL) is a devastating neurodegenerative lysosomal storage disease. Despite our knowledge that palmitoyl-protein thioesterase-1 (PPT1)-deficiency causes INCL, the molecular mechanism(s) of neurodegeneration and the drastically reduced lifespan of these patients remain poorly understood. Consequently, an effective treatment for this disease is currently unavailable. We previously reported that oxidative stress-mediated abnormality in mitochondria activates caspases-9 pathway of apoptosis in INCL fibroblasts and in neurons of Ppt1-knockout (Ppt1-KO) mice, which mimic INCL. Since mitochondria play critical roles in maintaining cellular energy homeostasis, we hypothesized that oxidative stress-mediated disruption of energy metabolism and homeostasis may contribute to INCL pathogenesis. We report here that, in cultured INCL fibroblasts and in the brain tissues of Ppt1-KO mice, the NAD(+)/NADH ratio, the levels of phosphorylated-AMPK (p-AMPK), peroxisome proliferator-activated receptor-γ (PPARγ) coactivator-1α (PGC-1α) and Silent Information Regulator T1 (SIRT1) are markedly down-regulated. This suggested an abnormality in AMPK/SIRT1/PGC-1α signaling pathway of energy metabolism. Moreover, we found that, in INCL fibroblasts and in the Ppt1-KO mice, phosphorylated-S6K-1 (p-S6K1) levels, which inversely correlate with lifespan, are markedly elevated. Most importantly, resveratrol (RSV), an antioxidant polyphenol, elevated the NAD(+)/NADH ratio, levels of ATP, p-AMPK, PGC-1α and SIRT1 while decreasing the level of p-S6K1 in both INCL fibroblasts and in Ppt1-KO mice, which showed a modest increase in lifespan. Our results show that disruption of adaptive energy metabolism and increased levels of p-S6K1 are contributing factors in INCL pathogenesis and provide the proof of principle that small molecules such as RSV, which alleviate these abnormalities, may have therapeutic potential.


Assuntos
Metabolismo Energético , Lipofuscinoses Ceroides Neuronais/metabolismo , Lipofuscinoses Ceroides Neuronais/patologia , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Ribossomos/metabolismo , Estilbenos/uso terapêutico , Regulação para Cima , Animais , Células Cultivadas , Fibroblastos/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NAD/metabolismo , Lipofuscinoses Ceroides Neuronais/tratamento farmacológico , Lipofuscinoses Ceroides Neuronais/genética , Estresse Oxidativo , Fosforilação , Resveratrol , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Tioléster Hidrolases/genética , Tioléster Hidrolases/metabolismo
11.
Sci Rep ; 13(1): 846, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36646766

RESUMO

Bridges might experience many defects during use, such as pavement cracks and reinforcement corrosion, which easily produce an accumulated impact that threatens bridge safety. Thus, there is a need for the regular inspection and maintenance of bridges. This paper presents a bridge maintenance system (BMS) based on building information modelling (BIM), which is utilized in bridge defect information management using a digitalization method. A bridge defect three-dimensional BIM (BIM3D) library is established and combined with a bridge model to visualize bridge defect conditions. Based on bridge inspection data, bridge defect information is digitally classified and encoded according to the international framework for dictionaries (IFD) standard and used to establish a database. An evaluation of bridge technical conditions is performed, and the results are graded and displayed in different colours, reflecting the visualization function of BIM technology. Maintenance suggestions are provided according to the range of bridge technical condition scores, reflecting the informatization function of BIM technology. With the Xinjiang Cocodala Bridge in China as a case study, a bridge BIM3D model and inspection data are imported into the BMS to utilize the functions of 'visualization of bridge defect conditions', 'evaluation of bridge technical conditions' and 'recommendations of bridge maintenance methods'.

12.
J Biol Chem ; 286(38): 32883-9, 2011 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-21799018

RESUMO

Allergic asthma is a chronic airway inflammatory disease in which exposure to allergens causes intermittent attacks of breathlessness, airway hyper-reactivity, wheezing, and coughing. Allergic asthma has been called a "syndrome" resulting from a complex interplay between genetic and environmental factors. Worldwide, >300 million individuals are affected by this disease, and in the United States alone, it is estimated that >35 million people, mostly children, suffer from asthma. Although animal models, linkage analyses, and genome-wide association studies have identified numerous candidate genes, a solid definition of allergic asthma has not yet emerged; however, such studies have contributed to our understanding of the multiple pathways to this syndrome. In contrast with animal models, in which T-helper 2 (T(H)2) cell response is the dominant feature, in human asthma, an initial exposure to allergen results in T(H)2 cell-dependent stimulation of the immune response that mediates the production of IgE and cytokines. Re-exposure to allergen then activates mast cells, which release mediators such as histamines and leukotrienes that recruit other cells, including T(H)2 cells, which mediate the inflammatory response in the lungs. In this minireview, we discuss the current understanding of how associated genetic and environmental factors increase the complexity of allergic asthma and the challenges allergic asthma poses for the development of novel approaches to effective treatment and prevention.


Assuntos
Asma/genética , Meio Ambiente , Asma/complicações , Asma/etiologia , Regulação da Expressão Gênica , Predisposição Genética para Doença , Humanos , Pneumonia/complicações , Pneumonia/genética , Síndrome
13.
Neurodegener Dis ; 9(4): 159-69, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22327870

RESUMO

Neuronal ceroid lipofuscinoses (NCLs) represent a group of common hereditary childhood neurodegenerative storage disorders that have no effective treatment. Mutations in eight different genes cause various forms of NCLs. Infantile NCL (INCL), the most lethal disease, is caused by inactivating mutations in the palmitoyl-protein thioesterase-1 (PPT1) gene. The availability of Ppt1-knockout (Ppt1-KO) mice, which recapitulate virtually all clinical and pathological features of INCL, provides an opportunity to test the effectiveness of novel therapeutic strategies in vivo. However, such studies will require noninvasive methods that can be used to perform serial evaluations of the same animal receiving an experimental therapy. Thus, the development of noninvasive method(s) of evaluation is urgently needed. Here, we report our evaluation of the progression of neurodegeneration in Ppt1-KO mice starting at 3 months of age by MRI and MR spectroscopy (MRS) and repeating these tests using the same mice at 4, 5 and 6 months of age. Our results showed progressive cerebral atrophy, which was associated with histological loss of neuronal content and increase in astroglia. Remarkably, while the brain volumes in Ppt1-KO mice progressively declined with advancing age, the MRS signals, which were significantly lower than those of their wild-type littermates, remained virtually unchanged from 3 to 6 months of age. In addition, our results also showed an abnormality in cerebral blood flow in these mice, which showed progression with age. Our findings provide methods to serially examine the brains of mouse models of neurodegenerative diseases (e.g. Ppt1-KO mice) using noninvasive and nonlethal procedures such as MRI and MRS. These methods may be useful in studies to understand the progression of neuropathology in animal models of neurodegenerative diseases as they allow repeated evaluations of the same animal in which experimental therapies are tested.


Assuntos
Progressão da Doença , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/patologia , Lipofuscinoses Ceroides Neuronais/diagnóstico , Lipofuscinoses Ceroides Neuronais/patologia , Envelhecimento/patologia , Animais , Astrócitos/patologia , Encéfalo/patologia , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doenças Neurodegenerativas/genética , Lipofuscinoses Ceroides Neuronais/genética , Neurônios/patologia , Tamanho do Órgão , Tioléster Hidrolases/deficiência , Tioléster Hidrolases/genética
14.
Sci Rep ; 12(1): 15308, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096934

RESUMO

Thermal loading is an important factor that could lead to the weakening and deterioration of rock materials. Understanding the thermal properties of rocks and their evolution under different high temperatures is important in the post-fire-hazard evaluation and cultural heritage conservation. Yet it is challenging to understand the evolution of thermally-induced changes in rock properties and to quantitatively study degrees of thermal damage when samples are limited. This study investigates the effects of high temperatures (i.e., 200 °C, 400 °C, 600 °C, 800 °C, and 1000 °C) on a dolomitic marble using combined mesoscopic and macroscopic testing techniques. The test results show that increasing marble temperature led to a deterioration of physical properties (i.e., increasing open porosity and weight loss; but decreasing P-wave velocity) and mechanical properties (i.e., increasing axial strain corresponding with the peak stress; but decreasing uniaxial compressive strength, Young's modulus, and brittleness). There existed a threshold temperature of 600 °C, which marks different thermal damage mechanisms. Below the threshold, the rock deterioration was mainly caused by physical changes such as crack propagation and grain breakage, which can be characterized by mesoscopic parameters (i.e., linear crack density and mineral grain size distribution). On the contrary, when the temperature was higher than the threshold, the deterioration was caused by chemical changes, including mineral decomposition and re-crystallization, which was indicated by the changes in mineral compositions and relative atomic mass calculation. Based on the experimental results (e.g., mineralogical and physico-mechanical changes) and obtained relationships between the parameters in mesoscale and macroscale, a novel scheme for thermal damage evaluation is proposed to estimate thermally-induced changes in macroscopic parameters (e.g., Young's modulus) based on the corresponding mesoscopic parameters (e.g., particle size distribution and linear crack density).

15.
Reprod Sci ; 29(8): 2299-2309, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35477839

RESUMO

The reversible lipid modification, S-palmitoylation, plays regulatory roles in various physiological processes, e.g., neuronal plasticity and organs development; however, the roles of palmitoylation engaged in testis have yet remained unexplored. Here, we used combined approaches of palm-proteomics, informatics and quantitative PCR to systematically analyze the expression of key enzymes related to protein palmitoylation and identify proteome-wide palmitoylated proteins during the processes of spermatogenesis. Specifically, different timepoints were chosen to collect samples to cover the initiation of meiosis (postnatal, P12), the appearance of the first batch of sperm (P36) and fully fertile status (P60) in mouse. Interestingly, our results showed that only a few enzymes related to protein palmitoylation are highly expressed at later stages (from P36 to P60), rather than in the earlier phase of testis development (P12). To focus on the molecular event of spermatogenesis, we examined the palm-proteomics of testes in P36 and P60 mouse. In total, we identified 4,883 palmitoylated proteins, among which 3,310 proteins match the published palmitoyl-proteome datasets and 1,573 proteins were firstly identified as palmitoylated proteins in this study. Informatics analysis suggested that palmitoylation is involved in events of protein transport, metabolic process, protein folding and cell adhesion, etc. Importantly, further analysis revealed that several networks of palmitoylated proteins are closely associated with sperm morphology and motility. Together, our study laid a solid ground for understanding the roles of protein palmitoylation in spermatogenesis for future studies.


Assuntos
Proteoma , Testículo , Animais , Lipoilação/fisiologia , Masculino , Camundongos , Proteoma/metabolismo , Proteômica/métodos , Sêmen/metabolismo , Testículo/metabolismo
16.
J Biol Chem ; 285(14): 10822-31, 2010 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-20118237

RESUMO

Emerging evidence indicates a link between inflammation and cancer metastasis, but the molecular mechanism(s) remains unclear. Uteroglobin (UG), a potent anti-inflammatory protein, is constitutively expressed in the lungs of virtually all mammals. UG-knock-out (UG-KO) mice, which are susceptible to pulmonary inflammation, and B16F10 melanoma cells, which preferentially metastasize to the lungs, provide the components of a model system to determine how inflammation and metastasis are linked. We report here that B16F10 cells, injected into the tail vein of UG-KO mice, form markedly elevated numbers of tumor colonies in the lungs compared with their wild type littermates. Remarkably, UG-KO mouse lungs overexpress two calcium-binding proteins, S100A8 and S100A9, whereas B16F10 cells express the receptor for advanced glycation end products (RAGE), which is a known receptor for these proteins. Moreover, S100A8 and S100A9 are potent chemoattractants for RAGE-expressing B16F10 cells, and pretreatment of these cells with a blocking antibody to RAGE suppressed migration and invasion. Interestingly, in UG-KO mice S100A8/S100A9 concentrations in blood are lowest in tail vein and highest in the lungs, which most likely guide B16F10 cells to migrate to the lungs. Further, B16F10 cells treated with S100A8 or S100A9 overexpress matrix metalloproteinases, which are known to promote tumor invasion. Most notably, the metastasized B16F10 cells in UG-KO mouse lungs express MMP-2, MMP-9, and MMP-14 as well as furin, a pro-protein convertase that activates MMPs. Taken together, our results suggest that a lack of an anti-inflammatory protein leads to increased pulmonary colonization of melanoma cells and identify RAGE as a potential anti-metastatic drug target.


Assuntos
Calgranulina A/metabolismo , Calgranulina B/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Inflamação/patologia , Neoplasias Pulmonares/secundário , Melanoma Experimental/patologia , Uteroglobina/fisiologia , Animais , Western Blotting , Calgranulina A/genética , Calgranulina B/genética , Adesão Celular , Movimento Celular , Células Cultivadas , Produtos Finais de Glicação Avançada/genética , Inflamação/imunologia , Inflamação/metabolismo , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo , Melanoma Experimental/imunologia , Melanoma Experimental/metabolismo , Camundongos , Camundongos Knockout , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais
17.
Endocr Rev ; 28(7): 707-25, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17916741

RESUMO

Blastokinin or uteroglobin (UG) is a steroid-inducible, evolutionarily conserved, secreted protein that has been extensively studied from the standpoint of its structure and molecular biology. However, the physiological function(s) of UG still remains elusive. Isolated from the uterus of rabbits during early pregnancy, UG is the founding member of a growing superfamily of proteins called Secretoglobin (Scgb). Numerous studies demonstrated that UG is a multifunctional protein with antiinflammatory/ immunomodulatory properties. It inhibits soluble phospholipase A(2) activity and binds and perhaps sequesters hydrophobic ligands such as progesterone, retinols, polychlorinated biphenyls, phospholipids, and prostaglandins. In addition to its antiinflammatory activities, UG manifests antichemotactic, antiallergic, antitumorigenic, and embryonic growth-stimulatory activities. The tissue-specific expression of the UG gene is regulated by several steroid hormones, although a nonsteroid hormone, prolactin, further augments its expression in the uterus. The mucosal epithelia of virtually all organs that communicate with the external environment express UG, and it is present in the blood, urine, and other body fluids. Although the physiological functions of this protein are still under investigation, a single nucleotide polymorphism in the UG gene appears to be associated with several inflammatory/autoimmune diseases. Investigations with UG-knockout mice revealed that the absence of this protein leads to phenotypes that suggest its critical homeostatic role(s) against oxidative damage, inflammation, autoimmunity, and cancer. Recent studies on UG-binding proteins (receptors) provide further insight into the multifunctional nature of this protein. Based on its antiinflammatory and antiallergic properties, UG is a potential drug target.


Assuntos
Fatores Imunológicos/fisiologia , Uteroglobina/fisiologia , Sequência de Aminoácidos , Animais , Regulação da Expressão Gênica , Hormônios Esteroides Gonadais/metabolismo , Humanos , Fatores Imunológicos/genética , Fatores Imunológicos/farmacologia , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/farmacologia , Polimorfismo Genético , Conformação Proteica , Coelhos , Proteínas Recombinantes/uso terapêutico , Uteroglobina/genética , Uteroglobina/farmacologia
18.
J Clin Invest ; 118(9): 3075-86, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18704195

RESUMO

Neuronal ceroid lipofuscinoses represent the most common childhood neurodegenerative storage disorders. Infantile neuronal ceroid lipofuscinosis (INCL) is caused by palmitoyl protein thioesterase-1 (PPT1) deficiency. Although INCL patients show signs of abnormal neurotransmission, manifested by myoclonus and seizures, the molecular mechanisms by which PPT1 deficiency causes this abnormality remain obscure. Neurotransmission relies on repeated cycles of exo- and endocytosis of the synaptic vesicles (SVs), in which several palmitoylated proteins play critical roles. These proteins facilitate membrane fusion, which is required for neurotransmitter exocytosis, recycling of the fused SV membrane components, and regeneration of fresh vesicles. However, palmitoylated proteins require depalmitoylation for recycling. Using postmortem brain tissues from an INCL patient and tissue from the PPT1-knockout (PPT1-KO) mice that mimic INCL, we report here that PPT1 deficiency caused persistent membrane anchorage of the palmitoylated SV proteins, which hindered the recycling of the vesicle components that normally fuse with the presynaptic plasma membrane during SV exocytosis. Thus, the regeneration of fresh SVs, essential for maintaining the SV pool size at the synapses, was impaired, leading to a progressive loss of readily releasable SVs and abnormal neurotransmission. This abnormality may contribute to INCL neuropathology.


Assuntos
Proteínas de Membrana/deficiência , Proteínas de Membrana/fisiologia , Lipofuscinoses Ceroides Neuronais/metabolismo , Neurônios/metabolismo , Vesículas Sinápticas/metabolismo , Tioléster Hidrolases/deficiência , Tioléster Hidrolases/fisiologia , Animais , Encéfalo/metabolismo , Membrana Celular/metabolismo , Células Cultivadas , Endocitose , Exocitose , Humanos , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Modelos Biológicos , Lipofuscinoses Ceroides Neuronais/patologia , Tioléster Hidrolases/genética
19.
Mol Genet Metab ; 104(3): 338-45, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21704547

RESUMO

Infantile neuronal ceroid lipofuscinosis (INCL), a lethal hereditary neurodegenerative lysosomal storage disorder, affects mostly children. It is caused by inactivating mutations in the palmitoyl-protein thioesterase-1(PPT1) gene. Nonsense mutations in a gene generate premature termination codons producing truncated,nonfunctional or deleterious proteins. PPT1 nonsense-mutations account for approximately 31% of INCL patients in the US. Currently, there is no effective treatment for this disease. While aminoglycosides such asgentamycin suppress nonsense mutations, inherent toxicity of aminoglycosides prohibits chronic use inpatients. PTC124 is a non-toxic compound that induces ribosomal read-through of premature termination codons. We sought to determine whether PTC124-treatment of cultured cells from INCL patients carrying nonsense mutations in the PPT1 gene would correct PPT1 enzyme-deficiency with beneficial effects. Our results showed that PTC124-treatment of cultured cells from INCL patients carrying PPT1 nonsense-mutations induced PPT1 enzymatic activity in a dose- and time-dependent manner. This low level of PPT1 enzyme activity induced by PTC124 is virtually identical to that induced by gentamycin-treatment. Even though only a modest increase in PPT1 activity was achieved by PTC124-treatment of INCL cells, this treatment reduced the levels of thioester (constituent of ceroid) load. Our results suggest that PTC124-treatment induces PPT1 enzymatic activity in cultured cells from INCL patients carrying PPT1 nonsense-mutations, and this modest enzymatic activity has demonstrable beneficial effects on these cells. The clinical relevance of these effects may be tested in animal models of INCL carrying nonsense mutations in the PPT1 gene.


Assuntos
Apoptose/efeitos dos fármacos , Códon de Terminação/efeitos dos fármacos , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Lipofuscinoses Ceroides Neuronais/tratamento farmacológico , Lipofuscinoses Ceroides Neuronais/fisiopatologia , Oxidiazóis/farmacologia , Células Cultivadas , Cromatografia em Camada Fina , Códon sem Sentido/genética , Relação Dose-Resposta a Droga , Indução Enzimática/efeitos dos fármacos , Imunofluorescência , Humanos , Proteínas de Membrana/metabolismo , Microscopia Eletrônica de Transmissão , Lipofuscinoses Ceroides Neuronais/genética , Sais de Tetrazólio , Tiazóis , Tioléster Hidrolases , Fatores de Tempo
20.
ACS Appl Mater Interfaces ; 13(1): 2007-2017, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33382243

RESUMO

Although the water-triggered bending behavior of bilayer films has been a wide concerned, there are few reports on wettability-controlled directional actuators with visible color changes. Using photonic crystals as carriers, bilayer directional bending structural color actuators were prepared based on the hydrophilic difference. Top inverse opal with strong hydrophilicity can promote water penetration and strengthen the effect of swelling. While, bottom inverse opal with weak hydrophilicity can inhibit water penetration and weaken the effect of swelling. When the bilayer structure is immersed in water, its wettability differences will produce different optical responses for visualization and will bring different swelling performances, resulting in directional bending. Infiltration differences are visualized as structural color red shifts or transparency. The mechanism of the design involves optical diffractions in the fabricated periodic nanostructures, differences in the surface wettability and swelling rate, uses the infiltration and capillary evaporation of water to realize the spectral diversity of reflectance, and the enhancement of bending by gradient infiltration. This work deeply analyzes the improvement of the photonic crystal structure on the optical and bending performance of the wettability-controlled actuator, provides a basic model for the design of bionic components, and opens an idea for the combination of bilayer photonic crystals and actuators.

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