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1.
J Biol Chem ; 297(1): 100811, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34023381

RESUMO

A20 is a potent anti-inflammatory protein that mediates both inflammation and ubiquitination in mammals, but the related mechanisms are not clear. In this study, we performed mass spectrometry (MS) screening, gene ontology (GO) analysis, and coimmunoprecipitation (co-IP) in a lipopolysaccharide (LPS)-induced inflammatory cell model to identify novel A20-interacting proteins. We confirmed that the E3 ubiquitin ligase Nrdp1, also known as ring finger protein 41 (RNF41), interacted with A20 in LPS-stimulated cells. Further co-IP analysis demonstrated that when A20 was knocked out, degradation-inducing K48-linked ubiquitination of inflammatory effector MyD88 was decreased, but protein interaction-mediating K63-linked ubiquitination of another inflammatory effector TBK1 was increased. Moreover, western blot experiments showed that A20 inhibition induced an increase in levels of MyD88 and phosphorylation of downstream effector proteins as well as of TBK1 and a downstream effector, while Nrdp1 inhibition induced an increase in MyD88 but a decrease in TBK1 levels. When A20 and Nrdp1 were coinhibited, no further change in MyD88 was observed, but TBK1 levels were significantly decreased compared with those upon A20 inhibition alone. Gain- and loss-of-function analyses revealed that the ZnF4 domain of A20 is required for Nrdp1 polyubiquitination. Upon LPS stimulation, the inhibition of Nrdp1 alone increased the secretion of IL-6 and TNF-α but decreased IFN-ß secretion, as observed in other studies, suggesting that Nrdp1 preferentially promotes the production of IFN-ß. Taken together, these results demonstrated that A20/Nrdp1 interaction is important for A20 anti-inflammation, thus revealing a novel mechanism for the anti-inflammatory effects of A20.


Assuntos
Inflamação/metabolismo , Lisina/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Poliubiquitina/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Animais , Ativação Enzimática , Inflamação/patologia , Interferons/metabolismo , Macrófagos/metabolismo , Camundongos , Modelos Biológicos , Ligação Proteica , Domínios Proteicos , Proteólise , Células RAW 264.7 , Transdução de Sinais , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/química
2.
Neurochem Res ; 47(11): 3369-3384, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35915371

RESUMO

Previous studies have shown that ovarian estrogens are involved in the occurrence and pathology of Alzheimer's disease (AD) through regulation on hippocampal synaptic plasticity and spatial memory; however, the underlying mechanisms have not yet been elucidated at the genomic scale. In this study, we established the postmenopausal estrogen-deficient model by ovariectomy (OVX). Then, we used high-throughput Affymetrix Clariom transcriptomics and found 143 differentially expressed genes in the hippocampus of OVX mice with the absolute fold change ≥ 1.5 and P < 0.05. GO analysis showed that the highest enrichment was seen in long-term memory. Combined with the response to steroid hormone enrichment and GeneMANIA network prediction, the serum and glucocorticoid-regulated kinase 1 gene (Sgk1) was found to be the most potent candidate for ovarian estrogenic regulation. Sgk1 overexpression viral vectors (oSgk1) were then constructed and injected into the hippocampus of OVX mice. Morris water maze test revealed that the impaired spatial learning and memory induced by OVX was rescued by Sgk1 overexpression. Additionally, the altered expression of synaptic proteins and actin remodeling proteins and changes in CA1 spine density and synapse density induced by OVX were also significantly reversed by oSgk1. Moreover, the OVX-induced increase in Aß-producing BACE1 and Aß and the decrease in insulin degrading enzyme were significantly reversed by oSgk1. The above results show that multiple pathways and genes are involved in ovarian estrogenic regulation of the function of the hippocampus, among which Sgk1 may be a novel potent target against estrogen-sensitive hippocampal dysfunctions, such as Aß-initiated AD.


Assuntos
Doença de Alzheimer , Proteínas Imediatamente Precoces , Insulisina , Proteínas Serina-Treonina Quinases , Actinas/metabolismo , Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Ácido Aspártico Endopeptidases/metabolismo , Estrogênios/metabolismo , Feminino , Hipocampo/metabolismo , Proteínas Imediatamente Precoces/genética , Insulisina/metabolismo , Aprendizagem em Labirinto , Camundongos , Proteínas Serina-Treonina Quinases/genética , Aprendizagem Espacial , Memória Espacial/fisiologia , Transcriptoma
3.
Neurochem Res ; 46(5): 1188-1202, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33559105

RESUMO

Ovarian estrogens (mainly 17ß estradiol, E2) have been involved in the regulation of the structure of hippocampus, the center of spatial memory. In recent years, high levels of aromatase (AROM), the estrogen synthase, has been localized in hippocampus; and this hippocampus-derived E2 seems to be functional in synaptic plasticity and spatial memory as ovarian E2 does. However, the contribution of ovarian E2 and hippocampal E2 to spatial memory and neural plasticity remains unclear. In this study, AROM-specific RNA interference AAVs (shAROM) were constructed and injected into the hippocampus of control or ovariectomized (OVX) mice. Four weeks later the spatial learning and memory behavior was examined with Morris water maze, the expression of hippocampal Aß related proteins, selected synaptic proteins and CA1 synapse density, actin polymerization related proteins and CA1 spine density were also examined. The results showed that while OVX and hippocampal shAROM contributed similarly to most of the parameters examined, shAROM induced more increase in BACE1 (amyloidogenic ß-secretase), more decrease in neprilysin (Aß remover) and Profilin-1 (actin polymerization inducer). More importantly, combined OVX and shAROM treatment displayed most significant impairment of spatial learning and memory as well as decrease in synaptic plasticity compared to OVX or shAROM alone. In conclusion, the above results clearly demonstrated the crucial role of hippocampal E2 in the regulation of the structure and function of hippocampus besides ovarian E2, indicating that hippocampal E2 content should also be taken into consideration during estrogenic replacement.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Aromatase/metabolismo , Plasticidade Neuronal/fisiologia , Memória Espacial/fisiologia , Animais , Aromatase/genética , Sequência de Bases , Região CA1 Hipocampal/enzimologia , Região CA1 Hipocampal/metabolismo , Espinhas Dendríticas/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Camundongos Endogâmicos C57BL , Teste do Labirinto Aquático de Morris/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Ovariectomia/efeitos adversos , Ovário/enzimologia , RNA Interferente Pequeno/farmacologia , Aprendizagem Espacial/fisiologia , Sinapses/metabolismo
4.
BMC Musculoskelet Disord ; 22(1): 949, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34781961

RESUMO

INTRODUCTION: Tendon diseases and injuries are a serious problem for the aged population, often leading to pain, disability and a significant decline in quality of life. The purpose of this study was to determine the influence of aging on biochemistry and histology during tendon healing and to provide a new strategy for improving tendon healing. METHOD: A total of 24 Sprague-Dawley rats were equally divided into a young and an aged group. A rat patellar tendon defect model was used in this study. Tendon samples were collected at weeks 2 and 4, and hematoxylin-eosin, alcian blue and immunofluorescence staining were performed for histological analysis. Meanwhile, reverse transcription-polymerase chain reaction (RT-PCR) and western blot were performed to evaluate the biochemical changes. RESULTS: The histological scores in aged rats were significantly lower than those in young rats. At the protein level, collagen synthesis-related markers Col-3, Matrix metalloproteinase-1 and Metallopeptidase Inhibitor 1(TIMP-1) were decreased at week 4 in aged rats compared with those of young rats. Though there was a decrease in the expression of the chondrogenic marker aggrecan at the protein level in aged tendon, the Micro-CT results from weeks 4 samples showed no significant difference(p>0.05) on the ectopic ossification between groups. Moreover, we found more adipocytes accumulated in the aged tendon defect with the Oil Red O staining and at the gene and protein levels the markers related to adipogenic differentiation. CONCLUSIONS: Our findings indicate that tendon healing is impaired in aged rats and is characterized by a significantly lower histological score, decreased collagen synthesis and more adipocyte accumulation in patellar tendon after repair.


Assuntos
Qualidade de Vida , Cicatrização , Envelhecimento , Animais , Ratos , Ratos Sprague-Dawley , Tendões
5.
Biodegradation ; 32(1): 73-85, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33442823

RESUMO

The effect of electricity, induced by external resistance, on microbial community performance is investigated in Microbial Fuel Cells (MFCs) involved in simultaneous biotransformation of sulfide and nitrate. In the experiment, three MFCs were operated under different external resistances (100 Ω, 1000 Ω and 10,000 Ω), while one MFC was operated with open circuit as control. All MFCs demonstrate good capacity for simultaneous sulfide and nitrate biotransformation regardless of external resistance. MFCs present similar voltage profile; however, the output voltage has positive relationship with external resistance, and the MFC1 with lowest external resistance (100 Ω) generated highest power density. High-throughput sequencing confirms that taxonomic distribution of suspended sludge in anode chamber encompass phylum level to genus level, while the results of principal component analysis (PCA) suggest that microbial communities are varied with external resistance, which external resistance caused the change of electricity generation and substrate removal at the same, and then leads to the change of microbial communities. However, based on Pearson correlation analyses, no strong correlation is evident between community diversity indices (ACE index, Chao index, Shannon index and Simpson index) and the electricity (final voltage and current density). It is inferred that the performance of electricity did not significantly affect the diversity of microbial communities in MFCs biotransforming sulfide and nitrate simultaneously.


Assuntos
Fontes de Energia Bioelétrica , Microbiota , Biodegradação Ambiental , Eletricidade , Eletrodos , Nitratos , Sulfetos
6.
J Cell Physiol ; 235(5): 4778-4789, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31637734

RESUMO

Tendinopathy is a common musculoskeletal system disorder in sports medicine, but regeneration ability of injury tendon is limited. Tendon stem cells (TSCs) have shown the definitive treatment evidence for tendinopathy and tendon injuries due to their tenogenesis capacity. Aspirin, as the representative of nonsteroidal anti-inflammatory drugs for its anti-inflammatory and analgestic actions, has been commonly used in treating tendinopathy in clinical, but the effect of aspirin on tenogenesis of TSCs is unclear. We hypothesized that aspirin could promote injury tendon healing through inducing TSCs tenogenesis. The aim of the present study is to make clear the effect of aspirin on TSC tenogenesis and tendon healing in tendinopathy, and thus provide new treatment evidence and strategy of aspirin for clinical practice. First, TSCs were treated with aspirin under tenogenic medium for 3, 7, and 14 days. Sirius Red staining was performed to observe the TSC differentiation. Furthermore, RNA sequencing was utilized to screen out different genes between the induction group and aspirin treatment group. Then, we identified the filtrated molecules and compared their effect on tenogenesis and related signaling pathway. At last, we constructed the tendinopathy model and compared biomechanical changes after aspirin intake. From the results, we found that aspirin promoted tenogenesis of TSCs. RNA sequencing showed that growth differentiation factor 6 (GDF6), GDF7, and GDF11 were upregulated in induction medium with the aspirin group compared with the induction medium group. GDF7 increased tenogenesis and activated Smad1/5 signaling. In addition, aspirin increased the expression of TNC, TNMD, and Scx and biomechanical properties of the injured tendon. In conclusion, aspirin promoted TSC tenogenesis and tendinopathy healing through GDF7/Smad1/5 signaling, and this provided new treatment evidence of aspirin for tendinopathy and tendon injuries.


Assuntos
Tendão do Calcâneo/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular/efeitos dos fármacos , Fatores de Diferenciação de Crescimento/metabolismo , Proteína Smad1/metabolismo , Proteína Smad5/metabolismo , Células-Tronco/efeitos dos fármacos , Tendinopatia/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Tendão do Calcâneo/metabolismo , Tendão do Calcâneo/patologia , Animais , Proteínas Morfogenéticas Ósseas/genética , Células Cultivadas , Modelos Animais de Doenças , Fatores de Diferenciação de Crescimento/genética , Masculino , Ratos Sprague-Dawley , Transdução de Sinais , Proteína Smad1/genética , Proteína Smad5/genética , Células-Tronco/metabolismo , Células-Tronco/patologia , Tendinopatia/genética , Tendinopatia/metabolismo , Tendinopatia/patologia
7.
J Cell Mol Med ; 23(11): 7535-7544, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31557405

RESUMO

Tendon injury repairs are big challenges in sports medicine, and fatty infiltration after tendon injury is very common and hampers tendon injury healing process. Tendon stem cells (TSCs), as precursors of tendon cells, have shown promising effect on injury tendon repair for their tenogenesis and tendon extracellular matrix formation. Adipocytes and lipids accumulation is a landmark event in pathological process of tendon injury, and this may induce tendon rupture in clinical practice. Based on this, it is important to inhibit TSCs adipogenesis and lipids infiltration to restore structure and function of injury tendon. Aspirin, as the representative of non-steroidal anti-inflammatory drugs (NSAIDs), has been widely used in tendon injury for its anti-inflammatory and analgesic actions, but effect of aspirin on TSCs adipogenesis and fatty infiltration is still unclear. Under adipogenesis conditions, TSCs were treated with concentration gradient of aspirin. Oil red O staining was performed to observe changes of lipids accumulation. Next, we used RNA sequencing to compare profile changes of gene expression between induction group and aspirin-treated group. Then, we verified the effect of filtrated signalling on TSCs adipogenesis. At last, we established rat tendon injury model and compared changes of biomechanical properties after aspirin treatment. The results showed that aspirin decreased lipids accumulation in injury tendon and inhibited TSCs adipogenesis. RNA sequencing filtrated PTEN/PI3K/AKT signalling as our target. After adding the signalling activators of VO-Ohpic and IGF-1, inhibited adipogenesis of TSCs was reversed. Still, aspirin promoted maximum loading, ultimate stress and breaking elongation of injury tendon. In conclusion, by down-regulating PTEN/PI3K/AKT signalling, aspirin inhibited adipogenesis of TSCs and fatty infiltration in injury tendon, promoted biomechanical properties and decreased rupture risk of injury tendon. All these provided new therapeutic potential and medicine evidence of aspirin in treating tendon injury and tendinopathy.


Assuntos
Adipogenia/efeitos dos fármacos , Aspirina/farmacologia , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células-Tronco/efeitos dos fármacos , Traumatismos dos Tendões/tratamento farmacológico , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Fator de Crescimento Insulin-Like I/metabolismo , Lipídeos , Ratos , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/metabolismo , Traumatismos dos Tendões/metabolismo , Tendões/efeitos dos fármacos , Tendões/metabolismo
8.
J Cell Mol Med ; 23(8): 5475-5485, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31148334

RESUMO

Tendon injuries are common musculoskeletal system disorders in clinical, but the regeneration ability of tendon is limited. Tendon stem cells (TSCs) have shown promising effect on tissue engineering and been used for the treatment of tendon injury. Exosomes that serve as genetic information carriers have been implicated in many diseases and physiological processes, but effect of exosomes from TSCs on tendon injury repair is unclear. The aim of this study is to make clear that the effect of exosomes from TSCs on tendon injury healing. Exosomes were harvested from conditioned culture media of TSCs by a sequential centrifugation process. Rat Achilles tendon tendinopathy model was established by collagenase-I injection. This was followed by intra-Achilles-tendon injection with TSCs or exosomes. Tendon healing and matrix degradation were evaluated by histology analysis and biomechanical test at the post-injury 5 weeks. In vitro, TSCs treated with interleukin 1 beta were added by conditioned medium including exosomes or not, or by exosomes or not. Tendon matrix related markers and tenogenesis related markers were measured by immunostaining and western blot. We found that TSCs injection and exosomes injection significantly decreased matrix metalloproteinases (MMP)-3 expression, increased expression of tissue inhibitor of metalloproteinase-3 (TIMP-3) and Col-1a1, and increased biomechanical properties of the ultimate stress and maximum loading. In vitro, conditioned medium with exosomes and exosomes also significantly decreased MMP-3, and increased expression of tenomodulin, Col-1a1 and TIMP-3. Exosomes from TSCs could be an ideal therapeutic strategy in tendon injury healing for its balancing tendon extracellular matrix and promoting the tenogenesis of TSCs.


Assuntos
Tendão do Calcâneo/metabolismo , Exossomos/metabolismo , Matriz Extracelular/metabolismo , Células-Tronco/metabolismo , Traumatismos dos Tendões/metabolismo , Cicatrização/fisiologia , Animais , Diferenciação Celular/fisiologia , Meios de Cultivo Condicionados/metabolismo , Interleucina-1beta/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual/métodos , Inibidor Tecidual de Metaloproteinase-3/metabolismo
9.
Exp Mol Pathol ; 110: 104283, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31301307

RESUMO

OBJECTIVES: Podocytes injury is a major contributor to the progression of diabetic nephropathy (DN). This study aims to investigate the role of long non-coding RNA SOX2OT in the high glucose (HG)-induced injury of human podocytes cells (HPCs) and the underlying mechanism. METHODS: HPCs proliferation and apoptosis were examined using MTT assay and flow cytometry assay, respectively. The protein levels of SIRT1 and autophagy-associated proteins (Beclin-1, LC3-II, Atg7, and p62) were determined using western blot. The interactions among SOX2OT, miR-9, and SIRT1 were investigated using luciferase activity assay. RESULTS: SOX2OT overexpression significantly alleviated the HG-induced HPCs injury and induced autophagy, which was abrogated by the autophagy inhibitor 3-MA and SIRT1 knockdown. Mechanistically, SOX2OT acted as a ceRNA by sponging miR-9 to facilitate SIRT1, and thus induce autophagy. CONCLUSION: SOX2OT overexpression alleviates the HG-induced podocytes injury through autophagy induction by the miR-9/SIRT1 axis.


Assuntos
Autofagia/efeitos dos fármacos , Glucose/farmacologia , MicroRNAs/genética , Podócitos/efeitos dos fármacos , RNA Longo não Codificante/genética , Sirtuína 1/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Humanos , Podócitos/metabolismo , Podócitos/patologia , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Sirtuína 1/metabolismo
10.
Cell Physiol Biochem ; 50(6): 2046-2059, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30415260

RESUMO

BACKGROUND/AIMS: Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in clinical practice to relieve fever and pain. Aspirin, as a representative NSAID, has been widely used in the treatment of tendinopathy. Some reports have demonstrated that aspirin can induce apoptosis in cancer cells. However, evidence regarding aspirin treatment for tendinopathy, especially the effect of this treatment on tendon stem cells (TSCs), is lacking. Understanding the effect of aspirin on tendinopathy may provide a basis for the rational use of NSAIDs in clinical practice. The aim of our study was to determine whether aspirin induces apoptosis in rat TSCs via the Wnt/ß-catenin pathway. METHODS: First, we used flow cytometry and fluorescence to detect TSC apoptosis. Protein expression of the apoptosis-related caspase-3 pathway was investigated via western blot analysis. Next, we used western blotting to determine the effect of aspirin on the Wnt/ß-catenin pathway. We used immunostaining to detect the levels of Bcl2, cleaved caspase-3, and P-ß-catenin in the Achilles tendon. Finally, we used flow cytometry, fluorescence, and western blotting to investigate the aspirin-induced apoptosis of TSCs via the Wnt/ß-catenin pathway. RESULTS: Aspirin induced morphological apoptosis in rat TSCs via the mitochondrial/caspase-3 pathway and induced cellular apoptosis in the Achilles tendon. Apoptosis was partly reversed after adding the Wnt signaling activator Wnt3a and lithium chloride (LiCl, a GSK-3ß inhibitor). Aspirin administration led to a dose-dependent increase in COX-2 expression. Apoptosis was promoted after adding the COX-2 inhibitor NS398. CONCLUSION: The Wnt/ß-catenin pathway plays a vital role in aspirin-induced apoptosis by regulating mitochondrial/caspase-3 function. Elevating COX-2 levels may protect cells against apoptosis. More importantly, the results remind us to consider the apoptotic effect of aspirin on TSCs and tendon cells when aspirin is administered to treat tendinopathy. The relationship between the positive and negative effects of aspirin remains a subject for future study.


Assuntos
Apoptose/efeitos dos fármacos , Aspirina/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Caspase 3/metabolismo , Ciclo-Oxigenase 2/química , Ciclo-Oxigenase 2/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/metabolismo , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Nitrobenzenos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Sulfonamidas/farmacologia , Tendões/citologia , Proteína Wnt3A/metabolismo , beta Catenina/metabolismo
11.
Biodegradation ; 29(4): 339-347, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29855740

RESUMO

The autotrophic process for nitrogen removal has attracted worldwide attention in the field of wastewater treatment, and the performance of this process is greatly influenced by the size of granular sludge particles present in the system. In this work, the granular sludge was divided into three groups, i.e. large size (> 1.2 mm), medium size (0.6-1.2 mm) and small size (< 0.6 mm). The medium granular sludge was observed to dominate at high volumetric nitrogen loading rates, while offering strong support for good performance. Its indispensable contribution was found to originate from improved settling velocity (0.84 ± 0.10 cm/s), high SOUR-A (specific oxygen uptake rate for ammonia oxidizing bacteria, 25.93 mg O2/g MLVSS/h), low SOUR-N (specific oxygen uptake rate for nitrite oxidizing bacteria, 3.39 mg O2/g MLVSS/h), and a reasonable microbial spatial distribution.


Assuntos
Processos Autotróficos , Nitrogênio/isolamento & purificação , Esgotos/microbiologia , Bactérias/metabolismo , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Desnitrificação , Fluorescência , Nitrogênio/análise , Tamanho da Partícula
12.
Ren Fail ; 40(1): 492-497, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30200803

RESUMO

BACKGROUND: Previous studies have shown that podocyte autophagy is an important trigger for proteinuria and glomerulosclerosis. The mammalian rapamycin target protein (mTOR) occupies a pivotal position in the autophagy pathway. In this study, we planned to clarify the mechanism of mTOR regulation of podocyte autophagy and the effect of rapamycin (RAPA). METHODS: All rats were randomly divided into normal control group (n = 8), DN group (n = 8), and RAPA group (n = 8). Blood and urine samples were collected at the 4th, 8th, and 12th weeks of the experiment. The serum creatinine (Scr), urine volume levels, and the 24 h urine protein (UP) levels were examined. The nephrin, podocin, mTOR, ribosomal S6 kinase 1 (S6K1), and autophagy marker light chain 3 (LC3II) expression levels were evaluated by immunohistochemistry, quantitative PCR, and immunoblotting. RESULTS: The urine volume, 24 h UP, and Scr of the DN and RAPA groups increased significantly compared with the NC group (p < .05). Nephrin and podocin expression was decreased in the kidney tissues of the DN and RAPA groups compared with the NC group (p < .05). The expression levels of mTOR and S6K1 increased and LC3II expression decreased in the renal tissues of the DN and RAPA groups compared with the NC group (p < .05). After RAPA treatment, all the above indexes were improved compared with the DN group (p < .05), but were significantly abnormal compared with the NC group (p < .05). CONCLUSION: The proteinuria and kidney function had improved after RAPA treatment. These results confirmed that RAPA specifically binds to mTOR kinase, and inhibits mTOR activity, thereby regulating the pathological autophagic process.


Assuntos
Autofagia/efeitos dos fármacos , Diabetes Mellitus Experimental/induzido quimicamente , Nefropatias Diabéticas/tratamento farmacológico , Podócitos/patologia , Proteinúria/tratamento farmacológico , Sirolimo/farmacologia , Animais , Creatinina/sangue , Nefropatias Diabéticas/induzido quimicamente , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Proteinúria/patologia , Ratos , Ratos Sprague-Dawley , Proteínas Quinases S6 Ribossômicas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estreptozocina , Serina-Treonina Quinases TOR/metabolismo
13.
Cell Physiol Biochem ; 36(2): 517-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25966835

RESUMO

BACKGROUND/AIMS: Tendinopathy is a common sports injury that is manifested by the heterotopic ossification of tendon tissue. Tendon stem cells (TSCs) are prone to osteogenic differentiation under excessive tension. The underlying mechanisms remain poorly understood. METHODS: Uniaxial mechanical tension (UMT) served to stretch rat tendon-derived stem cells (rTDSCs) at 8% elongation (frequency: 1 Hz; 48, 60, or 72 hours). RESULTS: The osteogenic differentiation of rTDSCs appeared after UMT along with increased mRNA expression of the osteogenic genes Runx2, Dlx5, Alpl, and Col1a1 and increased Runx2 protein expression. Wnt5a, Wnt5b and P-JNK protein levels were also upregulated after UMT stimulation. The inhibition of JNK expression by SP600125 and JNK1-shRNA decreased UMT-induced Runx2 protein expression, and the activation of JNK expression by anisomycin and JNK1-cDNA increased UMT-induced Runx2 protein expression. When shRNA knocked down Wnt5a and Wnt5b expression in rTDSCs, the induction of Runx2 and P-JNK expression by UMT was reduced. The inhibition of Runx2 expression could be rescued by the activation of JNK expression by anisomycin. CONCLUSION: UMT induced the osteogenic differentiation of rTDSCs via the Wnt5a/Wnt5b/JNK signaling pathway. Accordingly, this pathway may influence the heterotopic ossification of tendon tissue subjected to excessive tension.


Assuntos
Sistema de Sinalização das MAP Quinases , Osteogênese , Células-Tronco/citologia , Tendões/citologia , Proteínas Wnt/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Masculino , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Células-Tronco/metabolismo , Estresse Mecânico
14.
Cell Physiol Biochem ; 37(5): 1738-49, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26544628

RESUMO

BACKGROUND/AIMS: Dexamethasone (Dex)-induced spontaneous tendon rupture and decreased self-repair capability is very common in clinical practice. The metaplasia of adipose tissue in the ruptured tendon indicates that Dex may induce tendon stem cells (TSCs) to differentiate into adipocytes, but the mechanism remains unclear. In the present study, we used in vitro methods to investigate the effects of Dex on rat TSC differentiation and the molecular mechanisms underlying this process. METHODS: First, we used qPCR and Western blotting to detect the expression of the adipogenic differentiation markers aP2 and C/EBPα after treating the TSCs with Dex. Oil red staining was used to confirm that high concentration Dex promoted adipogenic differentiation of rat TSCs. Next, we used qPCR and Western blotting to detect the effect of a high concentration of dexamethasone on molecules related to the canonical WNT/ß-catenin pathway in TSCs. RESULTS: Treating rat TSCs with Dex promoted the synthesis of the inhibitory molecule dickkopf1 (DKK1) at the mRNA and protein levels. Western blotting results further showed that Dex downregulated the cellular signaling molecule phosphorylated glycogen synthase kinase-3ß (P-GSK-3 ß (ser9)), upregulated P-GSK-3ß (tyr216), and downregulated the pivotal signaling molecule ß-catenin. Furthermore, DKK1 knockdown attenuated Dex-induced inhibition of the canonical WNT/ß-catenin pathway and of the adipogenic differentiation of TSCs. Lithium chloride (LiCl, a GSK-3ß inhibitor) reduced Dex-induced inhibition of the classical WNT/ß-catenin pathway in TSCs and of the differentiation of TSCs to adipocytes. CONCLUSION: In conclusion, by upregulating DKK1 expression, reducing the level of P-GSK-3ß (ser9), and increasing the level of P-GSK-3ß (tyr216), Dex causes the degradation of ß-catenin, the central molecule of the classical WNT pathway, thereby inducing rat TSCs to differentiate into adipocytes.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Dexametasona/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Células-Tronco/citologia , Tendões/citologia , Regulação para Cima/efeitos dos fármacos , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Células Cultivadas , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/genética , Cloreto de Lítio/farmacologia , Fosforilação/efeitos dos fármacos , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Células-Tronco/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/genética , beta Catenina/metabolismo
15.
Cell Tissue Res ; 359(2): 577-587, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25358401

RESUMO

Tendon calcification is common in the Achilles tendon, and injuries affect not only athletes, but also the general population. However, the underlying cellular mechanisms are not yet fully understood. In this study, we isolated healthy human tenocytes and subjected them to uniaxial mechanical stretching (at 1.0 Hz) for various stretch times (4 h, 8 h, 12 h) or magnitudes (0%, 4%, 8%, 12%). The extracellular calcium chelator EGTA, calcium channel inhibitor MnCl2, nifedipine, or various doses of exogenous calcium were administered to these cells with or without mechanical overloading. The intracellular calcium concentration was determined by using a Fluo-3/AM fluorescence probe, and the cytoskeleton was revealed by F-actin Phalloidin staining. The intracellular calcium concentration increased in a magnitude- and time-dependent manner following stretching. These increases were suppressed by EGTA, MnCl2, or nifedipine. Additionally, cytoskeleton F-actin was disrupted significantly by stretching in a time-dependent manner. When extracellular calcium was applied, the intracellular calcium concentration increased, and F-actin was disrupted dramatically under mechanical stretching compared with non-stretched cells. Thus, repetitive mechanical overloading induces the accumulation of abnormally high concentrations of intracellular calcium resulting from extracellular calcium influx mediated, at least in part, by membrane calcium channels and finally causes cytoskeleton disorganization and tenocyte dysfunction. These findings provide novel experimental evidence for the pathology of tendon calcification and indicate that the blockade of calcium influx is a potential target for the prevention and treatment of calcific tendinopathy.


Assuntos
Tendão do Calcâneo/citologia , Cálcio/metabolismo , Citoesqueleto/metabolismo , Espaço Extracelular/metabolismo , Estresse Mecânico , Actinas/metabolismo , Adulto , Análise de Variância , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/metabolismo , Quelantes/farmacologia , Citoesqueleto/efeitos dos fármacos , Feminino , Fluorescência , Humanos , Espaço Intracelular/metabolismo , Masculino , Regulação para Cima/efeitos dos fármacos , Suporte de Carga , Adulto Jovem
16.
Tumour Biol ; 36(5): 3251-61, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25534237

RESUMO

Steroid receptors such as androgen receptor (AR) and estrogen receptors (ER) ER-α and ER-ß, and their receptor coactivators (steroid receptor coactivator, SRC) are widely localized in the brain. Although previous studies have investigated the expression of steroid receptors in brain tumors like astrocytoma, the studies on the expression of steroid receptors and SRCs in other brain tumors are lacking. Here, we investigated the expression of AR, ERs, and SRCs in neuroepithelial (medulloblastoma, ependymoma, oligodendroglioma) and meningothelial meningioma using tissue microarray immunohistochemistry. Compared to normal brain tissue, we found that the expression of SRC-1, SRC-3, and ER-α significantly decreased in meningothelial tumor and neuroepithelial tumor, suggesting that the SRC-1/SRC-3 levels may be regulated by ER-α. Moreover, the levels of AR strongly correlated to the levels of ER-ß. Furthermore, correlation was also detected between SRC-3 and AR in neuroepithelial tumor, and between ER-α and ER-ß in meningothelial tumor. In addition, the decreased ratio of SRC-1/SRC-3 was associated with an increase of ER-ß in neuroepithelial tumor. These results indicate that expressions of different steroid receptors and activators may be tumor type dependent. While AR, ER-α, and ER-ß may be involved in the pathogenesis of meningothelial tumor, SRCs/ER-ß axis and SRC-3/AR axis may play a role in the pathogenesis of neuroepithelial tumor.


Assuntos
Neoplasias Encefálicas/metabolismo , Neoplasias Meníngeas/metabolismo , Neoplasias Neuroepiteliomatosas/metabolismo , Adulto , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Coativador 1 de Receptor Nuclear/metabolismo , Coativador 2 de Receptor Nuclear/metabolismo , Receptores Androgênicos/metabolismo , Análise Serial de Tecidos , Adulto Jovem
17.
Artigo em Inglês | MEDLINE | ID: mdl-25594127

RESUMO

Using sodium fluoride as tracer, residence time distribution technique was employed to evaluate the hydraulic characteristics of a pilot-scale Internal-Loop Airlift Bio-particle (ILAB) bioreactor that was a novel system for ammonia removal from wastewater. The results showed that the flow pattern of ILAB reactor was close to completely mixed reactor under all the tested air flow rates and liquid flow rates (with average N of 1.88). The total dead zone (TDZ) was 32.43% with biological dead zone (BDZ) of 20.66% and hydraulic dead zone (HDZ) of 8.95%. At higher air flow rates, the flow pattern of reactor approached that of completely mixed reactor (N from 2.72 to 1.54), and the increase of air flow rate gave rise to the decrease of TDZ in the reactor (from 36.24% to 23.00%). Whereas at higher liquid flow rates, the flow pattern of ILAB reactor got away from that of completely mixed reactor (N from 1.51 to 1.72), and the increase of liquid flow rate yielded a rise of TDZ in the reactor (from 28.48% to 36.84%). The study highlighted that the effect of air flow rate on flow pattern and TDZ of the reactor was greater than that of liquid flow rate.


Assuntos
Reatores Biológicos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Desenho de Equipamento , Hidrodinâmica , Projetos Piloto
18.
Zhongguo Zhong Yao Za Zhi ; 40(15): 3100-9, 2015 Aug.
Artigo em Zh | MEDLINE | ID: mdl-26677718

RESUMO

To systematically evaluate the efficacy and safety of tripterygium glycosides (TG) combined with ACEI/ARB preparation in treating diabetic nephropathy stage IV. The computer retrievals were made in Cochrane Libarary, PubMed, Embase, SCI, Sinnomed, CNKI, Chinainfo and VIP, and hand retrievals were conducted for meeting and academic papers (updated to December 30, 2014), in order to collect randomized controlled trials and quasi-randomized control trials for TG combined with ACEI/ARB preparation in treating diabetic nephropathy stage IV and set the literature inclusion and elimination standards. Eligible literatures were included and evaluated according to standards in Cochrane Handbook. RevMan 5.3 and Stata 12.0 were used for a Meta-analysis. A total of 13 randomized controlled trials and quasi-randomized control trials involving 1119 patients with diabetic nephropathy were included. The Meta analysis result showed that compared with the control group, the combination group showed better effects in reducing the 24-hour urinary protein [MD = -0.84, 95% CI (-1.02, -0.66)], raising albumin [SMD = 0.98, 95% CI (0.81, 1.16)], the total efficiency [OR = 4.23, 95% CI (2.77, 6.46)] and the significant efficiency [OR = 5.35, 95% CI (2.70, 10.60)], with no statistical difference in Serum Creatinine between Both groups [MD = -0.82, 95% CI (-4.30, 2.66), P = 0.64]. However, the risk of adverse reactions increased by 7% [RD = 0.07, 95% CI (0.03, 0.12)]. The Egger's test showed no publication bias. Tripterygium Glycosides combined with ACEI/ARB in treating diabetic nephropathy stage IV is supper than the single administration of ACEI/ARB, with a good prospect in clinical application. Nevertheless, due to the small-size and low-quality samples in this study, more high-quality and large sample-size randomized controlled trials shall be conducted to verify the findings.


Assuntos
Antagonistas de Receptores de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Nefropatias Diabéticas/tratamento farmacológico , Glicosídeos/administração & dosagem , Tripterygium/química , Quimioterapia Combinada , Humanos
19.
Appl Microbiol Biotechnol ; 98(3): 1357-66, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23749227

RESUMO

The compartmentalized anaerobic reactor (CAR) is a patent novel high-rate reactor, which consists of three compartments. The reactor has a great potential for application due to its many advantages. In this work, the microbial consortium, spatial distribution, and their relationship with performance of CAR were investigated by means of polymerase chain reaction, denaturing gradient gel electrophoresis, and fluorescence in situ hybridization. The results showed that the predominant archaea were Methanobacterium, Methanosaeta, and Methanospirillum, and the predominant bacteria were Firmicutes, Deltaproteobacteria, Spirochaetes, Actinobacteria, and Gammaproteobacteria in the microbial consortium. The methanogenic archaea (MA), the hydrogen-producing acetogenic bacteria (HAB), and the hydrolytic fermentative bacteria (HFB) were found to be predominant in the upper, middle, and bottom compartments, respectively. The results revealed that the granular sludge took on a stratified microbial structure. The HFB, HAB, and MA were located in the outer shell, middle layer, and core, respectively. The microbial populations from the bottom compartment were relatively homogeneous in the granular sludge, and from the middle and upper compartments, they were relatively heterogeneous in the granular sludge. The microbial consortia and their spatial distribution were in accordance with the organic loading rate and chemical components in the three compartments.


Assuntos
Archaea/isolamento & purificação , Bactérias/isolamento & purificação , Reatores Biológicos/microbiologia , Biota , Consórcios Microbianos , Anaerobiose , Archaea/classificação , Archaea/genética , Bactérias/classificação , Bactérias/genética , Eletroforese em Gel de Gradiente Desnaturante , Hibridização in Situ Fluorescente , Reação em Cadeia da Polimerase , Esgotos/microbiologia
20.
Cell Mol Biol Lett ; 19(2): 233-42, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24728800

RESUMO

Radiotherapy and chemotherapeutic agents that damage DNA are the current major non-surgical means of treating cancer. However, many patients develop resistances to chemotherapy drugs in their later lives. The PI3K and Ras signaling pathways are deregulated in most cancers, so molecularly targeting PI3K-Akt or Ras-MAPK signaling sensitizes many cancer types to radiotherapy and chemotherapy, but the underlying molecular mechanisms have yet to be determined. During the multi-step processes of tumorigenesis, cancer cells gain the capability to disrupt the cell cycle checkpoint and increase the activity of CDK4/6 by disrupting the PI3K, Ras, p53, and Rb signaling circuits. Recent advances have demonstrated that PI3K-Akt-mTOR signaling controls FANCD2 and ribonucleotide reductase (RNR). FANCD2 plays an important role in the resistance of cells to DNA damage agents and the activation of DNA damage checkpoints, while RNR is critical for the completion of DNA replication and repair in response to DNA damage and replication stress. Regulation of FANCD2 and RNR suggests that cancer cells depend on PI3K-Akt-mTOR signaling for survival in response to DNA damage, indicating that the PI3K-AktmTOR pathway promotes resistance to chemotherapy and radiotherapy by enhancing DNA damage repair.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/terapia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Antineoplásicos/farmacologia , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Ribonucleotídeo Redutases/metabolismo , Transdução de Sinais/efeitos dos fármacos
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