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1.
Cell ; 148(5): 1039-50, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22385967

RESUMO

Impairment of working memory is one of the most important deleterious effects of marijuana intoxication in humans, but its underlying mechanisms are presently unknown. Here, we demonstrate that the impairment of spatial working memory (SWM) and in vivo long-term depression (LTD) of synaptic strength at hippocampal CA3-CA1 synapses, induced by an acute exposure of exogenous cannabinoids, is fully abolished in conditional mutant mice lacking type-1 cannabinoid receptors (CB(1)R) in brain astroglial cells but is conserved in mice lacking CB(1)R in glutamatergic or GABAergic neurons. Blockade of neuronal glutamate N-methyl-D-aspartate receptors (NMDAR) and of synaptic trafficking of glutamate α-amino-3-hydroxy-5-methyl-isoxazole propionic acid receptors (AMPAR) also abolishes cannabinoid effects on SWM and LTD induction and expression. We conclude that the impairment of working memory by marijuana and cannabinoids is due to the activation of astroglial CB(1)R and is associated with astroglia-dependent hippocampal LTD in vivo.


Assuntos
Astrócitos/metabolismo , Canabinoides/farmacologia , Hipocampo/metabolismo , Memória de Curto Prazo/efeitos dos fármacos , Receptor CB1 de Canabinoide/metabolismo , Animais , Cannabis/química , Hipocampo/citologia , Depressão Sináptica de Longo Prazo/efeitos dos fármacos , Camundongos , Plasticidade Neuronal , Ratos , Receptor CB1 de Canabinoide/genética
2.
Childs Nerv Syst ; 40(2): 549-553, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37552306

RESUMO

Angiolipomas are slow-growing benign mesenchymal-derived tumors consisting of mature adipocytes and thin-walled blood vessels. While the majority of angiolipomas are found in subcutaneous tissues, rarely there are case reports of intracranial lesions. We present a case of cisternal angiolipoma in a 10-year-old female. She presented with vague symptoms like dizziness without neurological deficits and radiological evaluation confirmed a left-sided infratentorial cisternal partially enhancing mass. She underwent craniotomy and had complete resection of the mass, which was histologically composed of mature adipocytes and blood vessels, consistent with angiolipoma. A review of the literature found only 18 cases of intracranial angiolipoma ever reported with our case representing the first case of infratentorial cisternal region.


Assuntos
Angiolipoma , Feminino , Humanos , Criança , Angiolipoma/diagnóstico por imagem , Angiolipoma/cirurgia , Radiografia , Tela Subcutânea/patologia , Tela Subcutânea/cirurgia , Craniotomia
3.
Development ; 147(8)2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32341029

RESUMO

Mammalian oocytes are arrested at G2/prophase of the first meiosis. After a hormone surge, oocytes resume meiosis, undergoing germinal vesicle breakdown (GVBD). This process is regulated by Cdk1/cyclin B1. Here, we report that Mis12 is required for G2/M transition by regulating cyclin B1 accumulation via Cdc14B-mediated APC/CCdh1 regulation, but is not essential for spindle and chromosome dynamics during meiotic maturation. Depletion of Mis12 severely compromised GVBD by impairing cyclin B1 accumulation. Importantly, impaired GVBD after Mis12 depletion was rescued not only by overexpressing cyclin B1 but also by depleting Cdc14B or Cdh1. Notably, oocytes rescued by cyclin B1 overexpression exhibited normal spindle and chromosome organization with intact kinetochore-microtubule attachments. In addition, after being rescued by cyclin B1 overexpression, Mis12-depleted oocytes normally extruded polar bodies. Moreover, Mis12-depleted oocytes formed pronuclear structures after fertilization but failed to develop beyond zygotes. Interestingly, Mis12 was localized in the cytoplasm and spindle poles in oocytes, in contrast to kinetochore localization in somatic cells. Therefore, our results demonstrate that Mis12 is required for meiotic G2/M transition but is dispensable for meiotic progression through meiosis I and II.


Assuntos
Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Ciclina B1/metabolismo , Fosfatases de Especificidade Dupla/metabolismo , Fase G2 , Meiose , Proteínas Associadas aos Microtúbulos/metabolismo , Oócitos/metabolismo , Animais , Feminino , Cinetocoros/metabolismo , Camundongos , Modelos Biológicos , Membrana Nuclear/metabolismo , Estabilidade Proteica , Fuso Acromático/metabolismo , Polos do Fuso/metabolismo
4.
Philos Trans A Math Phys Eng Sci ; 381(2260): 20220384, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37742710

RESUMO

For the fatigue reliability analysis of aeroengine blade-disc systems, the traditional direct integral modelling methods or separate independent modelling methods will lead to low computational efficiency or accuracy. In this work, a physics-informed ensemble learning (PIEL) method is proposed, i.e. firstly, based on the physical characteristics of blade-disc systems, the complex multi-component reliability analysis is split into a series of single-component reliability analyses; moreover, the PIEL model is established by introducing the mapping of multiple constitutive responses and the multi-material physical characteristics into the ensemble learning; finally, the PIEL-based system reliability framework is established by quantifying the failure correlation with the Copula function. The reliability analysis of a typical aeroengine high-pressure turbine blade-disc system is regarded as an example to verify the effectiveness of the proposed method. Compared with the direct Monte Carlo, support vector regression, neural network, ensemble learning and physics-informed neural network, the proposed method exhibits the highest computing accuracy and efficiency, and is validated to be an efficient method for the reliability analysis of blade-disc systems. The current work can provide a novel insight for physics-informed modelling and fatigue reliability analyses. This article is part of the theme issue 'Physics-informed machine learning and its structural integrity applications (Part 1)'.

5.
Environ Toxicol ; 38(6): 1217-1225, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36999488

RESUMO

Circular RNAs (circRNAs) are linked to the regulation of sepsis-induced acute kidney injury (AKI). However, the function of circITCH in the development of sepsis-induced AKI is still unclear. The levels of circITCH, miR-579-3p and ZEB2 were examined by real-time PCR and immunoblotting. Then, the roles of circITCH in cell viability, apoptosis, and inflammation in lipopolysaccharide (LPS)-treated HK-2 cells were evaluated. The further mechanism was investigated using rescue assays. CircITCH was downregulated in septic AKI patients and LPS-triggered HK-2 cells. CircITCH overexpression restored cell viability in LPS-treated HK-2 cells and restrained apoptosis and inflammatory cytokine production. CircITCH negatively regulated miR-579-3p, thereby upregulating ZEB2 expression. Taken together, circITCH alleviates LPS-induced HK-2 cell injury by regulating miR-579-3p/ZEB2 signal axis, which provides a theoretical basis for AKI therapy.


Assuntos
Injúria Renal Aguda , MicroRNAs , Sepse , Humanos , Lipopolissacarídeos/farmacologia , Injúria Renal Aguda/genética , Sepse/complicações , Sepse/genética , Apoptose/genética , MicroRNAs/genética , Homeobox 2 de Ligação a E-box com Dedos de Zinco/genética
6.
Biol Chem ; 403(7): 665-678, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35089659

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common human cancers. Long non-coding RNA (lncRNA) has been demonstrated to play an important role in regulating tumor development. The current study aims to explore the specific role of LINC00520 during HCC progression. The present study identified that LINC00520 was upregulated in HCC tissues and indicated poor patient survival. Overexpression of LINC00520 promoted HCC cell proliferation, migration and invasion, while LINC00520 downregulation led to the opposite effects. Besides, LINC00520 knockdown was found to inhibit tumor growth in vivo. Furthermore, LINC00520 acted as a sponge of miR-4516 to regulate SRY-related high mobility group box 5 (SOX5). In addition, the inhibition of miR-4516 partly reversed the inhibitory effect of LINC00520 silencing on HCC cell proliferation, migration and invasion. In conclusion, the inhibition of LINC00520 suppressed HCC cell proliferation, migration and invasion through mediating miR-4516/SOX5 axis. Therefore, our study provides a basis for the development of treatment strategies for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , RNA Longo não Codificante , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/genética , RNA Longo não Codificante/genética , Fatores de Transcrição SOXD/genética
7.
Neurochem Res ; 47(5): 1405-1418, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35092569

RESUMO

Epigenetic regulation of gene expression has been implicated in the development of chronic pain. However, little is known about whether this regulation is involved in the development and treatment of chronic pain comorbidities such as fibromyalgia syndrome (FMS) and temporomandibular disorder (TMD), a comorbidity predominantly occurring among women. Here we explored the impact of the histone deacetylase (HDAC) inhibitor suberoylanilide hydroxamic acid (SAHA) on somatic hyperalgesia induced by stress or stress combined with orofacial inflammation, which mimicked the comorbidity of FMS and TMD in rats. Our data showed that somatic thermal hyperalgesia and mechanical allodynia induced by both conditions were completely prevented by intrathecal injection of SAHA, which upregulated 5-HT2C receptors but downregulated 5-HT3 receptors in the spinal dorsal horn. Subsequent spinal administration of RS102221 to inhibit 5-HT2C receptors or SR57227 to activate 5-HT3 receptors reversed the analgesic effect of SAHA under both conditions. These results indicate that SAHA attenuates the pro-nociceptive effects of stress combined with orofacial inflammation and the effects of stress alone. This likely occurs through epigenetic regulation of spinal 5-HT2C and 5-HT3 receptor expression, suggesting that SAHA has potential therapeutic value in FMS or comorbid FMS-TMD patients with somatic hyperalgesia.


Assuntos
Epigênese Genética , Hiperalgesia , Animais , Feminino , Hiperalgesia/induzido quimicamente , Hiperalgesia/tratamento farmacológico , Inflamação/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Receptores de Serotonina , Medula Espinal , Vorinostat/farmacologia , Vorinostat/uso terapêutico
8.
J Transl Med ; 19(1): 504, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876144

RESUMO

BACKGROUND: LINC00491 was involved in some tumors development, but its function in liver cancer has not been reported. This study aimed to investigate LINC00491 expression and function in liver cancer progression. METHODS: Sixty liver cancer cases were enrolled. LINC00491, miR-324-5p and rho-associated kinase 1 (ROCK1) expression in liver cancer patients and cells were detected by quantitative reverse transcription-polymerase chain reaction and Western blot. HUH-7 and SK-Hep-1 cells were transfected to modulate LINC00491, miR-324-5p and ROCK1 expression. Cell counting kit-8 assay, colony formation assay, wound healing assay, Transwell experiment, Tunel assay and flow cytometry were performed to detected HUH-7 and SK-Hep-1 cells proliferation, migration, invasion, apoptosis and cell cycle. Biotin-RNA pull-down assay and Dual-Luciferase Reporter Assay was performed to detect the binding among LINC00491, miR-324-5p and ROCK1. Xenograft tumor and lung metastasis was performed using nude mice. Xenograft tumor and lung tissues of mice were experienced immunohistochemistry and hematoxylin-eosin staining. RESULTS: LINC00491 was highly expressed in liver cancer cases, associating with poor prognosis. si-LINC00491 inhibited proliferation, colony formation, invasion, migration, and induced cell cycle G1 arrest and apoptosis in HUH-7 and SK-Hep-1 cells. LINC00491 overexpression showed opposite effects. LINC00491 promoted ROCK1 expression by reducing miR-324-5p. miR-324-5p up-regulation or ROCK1 knockdown reversed LINC00491 promotion on liver SK-Hep-1 cells malignant phenotype. LINC00491 facilitated xenograft tumor growth and lung metastasis in mice. CONCLUSION: LINC00491 was highly expressed in liver cancer patients, associating with poor prognosis. LINC00491 facilitated liver cancer progression by sponging miR-324-5p/ROCK1. LINC00491 might be a potential treatment target of liver cancer.


Assuntos
Neoplasias Hepáticas , MicroRNAs , Animais , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Nus , MicroRNAs/genética , Quinases Associadas a rho/genética , Quinases Associadas a rho/metabolismo
9.
J Stroke Cerebrovasc Dis ; 29(10): 105113, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32912517

RESUMO

BACKGROUND: Swallowing disorders (dysphagia) is common in stroke patients. However, the epidemiology of post-stroke dysphagia (PSD) is poorly described. We herein synthesize the data of eligible studies on occurrence rate of dysphagia in Asian populations with stroke. METHODS: We searched the electronic databases (PubMed, Embase and Web of Science) to collect the studies on the prevalence of PSD. We used the Newcastle-Ottawa Scale (NOS) to estimate the quality of studies. The pooled dysphagia occurrence rate was obtained in Asian stroke patients. RESULTS: 40 studies (including 43 observations) from 2318 initial references were selected in the synthetic analysis. The pooled occurrence rate of dysphagia in post-stroke patients was 36.3% (95% CI, 33.3%-39.3%). Meta-regression analysis showed that the "country" and "developing level" may influence the pooled occurrence rate of PSD. CONCLUSION: Dysphagia is common in Asian post-stroke patients. Our meta-analysis may raise concern about evaluating and managing dysphagia in stroke patients.


Assuntos
Povo Asiático , Transtornos de Deglutição/etnologia , Deglutição , Acidente Vascular Cerebral/etnologia , Idoso , Idoso de 80 Anos ou mais , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia
10.
J Cell Mol Med ; 23(1): 586-595, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30417527

RESUMO

Hepatocellular carcinoma (HCC) is a high incidence and mortality malignant tumour globally. Betulinic acid (BA) is a pentacyclic triterpenoid with potential pro-apoptotic activities which widely found in many plants. In this study, we determined the effects of BA on proliferation, apoptosis, invasion, and metastasis in HCC cell lines and on tumour growth and pulmonary metastasis in mice. The results suggested that BA could inhibit cell viability and proliferation of HCC cell lines including HepG2, LM3, and MHCC97H. In addition, BA induced apoptosis of HepG2 cells characterised condensed nuclei and nuclear fragmentation. Moreover, western blot analysis showed that BA-induced apoptosis associated with increasing of pro-apoptotic protein Bax and cleaved caspase-3 and decreasing of anti-apoptotic protein Bcl-2. Meanwhile, BA also reduced the reactive oxygen species (ROS) level. Furthermore, BA also significantly inhibited HCC growth in vivo and blocked pulmonary metastasis of HCC by regulating the metastasis-related proteins including MMP-2, MMP-9, and TIMP2 without obvious toxicity. In all, the present study suggested that BA might be a promising anti-HCC drug candidate by inhibiting proliferation, inducing apoptosis, and blocking metastasis.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Triterpenos/farmacologia , Animais , Carcinoma Hepatocelular/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Triterpenos Pentacíclicos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína X Associada a bcl-2/metabolismo , Ácido Betulínico
11.
Dev Biol ; 439(1): 42-51, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29679558

RESUMO

Most, if not all, stem cells reside in a defined microenvironment, called the niche. Short-ranged niche signal must be tightly controlled to be active only inside the niche to maintain the proper balance of stem cell self-renewal verse differentiation. However, how niche components restrict localized niche signal activation remains largely unknown. Here, we find that Thickveins (Tkv, a type I receptor of the Dpp signaling pathway) in cyst stem cells (CySCs) of the testis niche prevents Dpp signaling activation outside of the niche. We show that Tkv functions as Dpp trap/sink to spatially restrain Dpp signaling inside the niche. This self-restrained regulation of niche activity by Tkv in CySCs is independent of the canonical Dpp signaling pathway. Our data demonstrate the critical roles of niche components (CySCs) in the self-restrained regulation of niche activity, which could be shed light on niche activity regulation in general.


Assuntos
Proteínas de Drosophila/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Nicho de Células-Tronco/genética , Nicho de Células-Tronco/fisiologia , Animais , Diferenciação Celular/fisiologia , Drosophila/embriologia , Drosophila/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Células Germinativas/citologia , Masculino , Proteínas Serina-Treonina Quinases/fisiologia , Receptores de Superfície Celular/fisiologia , Transdução de Sinais/fisiologia , Células-Tronco/citologia , Testículo/metabolismo , Testículo/fisiologia
12.
J Pineal Res ; 67(4): e12603, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31370106

RESUMO

Mammalian oocytes remain arrested at the first prophase of meiosis in ovarian follicles for an extended period. During this protracted arrest, oocytes are remarkably susceptible to the accumulation of DNA damage. Melatonin (N-acetyl-5-methoxytryptamine), a hormone secreted by the pineal gland, has diverse effects on various physiological processes. However, the effect of melatonin on DNA damage response in mammalian oocytes has not been explored. Here, we showed that melatonin protected mouse oocytes from DNA damage induced by double-strand breaks (DSBs) during prophase arrest and subsequently improved oocyte quality. We found that DNA damage during prophase arrest impaired subsequent meiotic maturation and deteriorated oocyte quality, increasing chromosome fragmentation, spindle abnormality, mitochondrial aggregation, and oxidative stress. However, melatonin treatment during DNA damage accumulation at prophase improved meiotic maturation and relieved the quality decline of oocytes. In addition, melatonin inhibited the accumulation of DNA damage during prophase arrest by reducing the γ-H2AX levels. Although activated ATM levels were decreased by melatonin treatment, the effect of melatonin on DNA damage response was not a direct consequence of ATM inhibition. Instead, melatonin enhanced DNA repair via nonhomologous end-joining (NHEJ) pathway. Interestingly, these actions of melatonin on DNA damage response are receptor-independent in mouse oocytes. Therefore, our results demonstrated that melatonin protects oocytes from DNA damage during prophase arrest by enhancing DNA repair via NHEJ and subsequently prevents the deterioration of oocyte quality during meiotic maturation.


Assuntos
Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Reparo do DNA por Junção de Extremidades/efeitos dos fármacos , Melatonina/farmacologia , Oócitos/metabolismo , Animais , Feminino , Camundongos , Camundongos Endogâmicos ICR , Oócitos/patologia
13.
Zhonghua Nan Ke Xue ; 25(5): 302-308, 2019 Apr.
Artigo em Zh | MEDLINE | ID: mdl-32216210

RESUMO

OBJECTIVE: To investigate oxidative stress-mediated damage to the epididymal epithelial tight junction protein ZO-1 and its impact on epididymal function in varicocele rats. METHODS: We randomly divided 45 male adolescent SD rats into three groups of equal number: sham operation (left renal vein exposed and isolated), experimental (left renal vein constricted and collaterals of the left spermatic vein fully ligated), and treatment (60-day intragastric administration of vitamin E at 150 mg/kg/d after modeling). At 60 days after modeling, we observed the histological changes in the left epididymis, detected the expressions of ZO-1 and other tight junction-related proteins by real-time quantitative PCR, immunohistochemistry, immunofluorescence staining and Western blotting, determined sperm motility, and measured the levels of superoxide dismutase (SOD), total antioxidant capacity (T-AOC), methylene dioxyamphetamine (MDA) and α-glucosidase (α-Glu) in the epididymal tissue of the rats. RESULTS: Compared with the rats of the sham operation group, those of the experimental group showed disorganized epithelial structure and decreased number of epithelial cells in the left epididymis, with some epithelial cells desquamated into the lumen. The expression of ZO-1 was significantly lower in the experimental than in the sham operation group (P < 0.05) but markedly upregulated after VE treatment (P < 0.05). In comparison with the sham operation group, the animals in the experimental group exhibited remarkably increased content of MDA in the epididymal tissue (ï¼»0.41 ± 0.05ï¼½ vs ï¼»1.21 ± 0.18ï¼½ nmol/mg prot, P < 0.05) but decreased levels of SOD (ï¼»814.65 ± 73.64ï¼½ vs ï¼»298.62 ± 67.84ï¼½ U/mg prot, P < 0.05), T-AOC (ï¼»0.84 ± 0.07ï¼½ vs ï¼»0.24 ± 0.04ï¼½ nmol/mg prot, P < 0.05) and α-Glu (ï¼»11.72 ± 2.72ï¼½ vs ï¼»5.82 ± 1.24ï¼½ U/mg prot, P < 0.05). VE treatment, however, remarkably reduced the content of MDA (ï¼»0.69 ± 0.12ï¼½ nmol/mg prot) and elevated the levels of SOD (ï¼»497.73 ± 48.03ï¼½ U/mg prot), T-AOC (ï¼»0.42 ± 0.06ï¼½ nmol/mg prot) and α-Glu (ï¼»9.11 ± 1.91ï¼½ U/mg prot) as compared with those in the experimental group (all P < 0.05). The percentage of progressively motile sperm was significantly lower in the experimental than in the sham operation group (ï¼»31.33 ± 6.32ï¼½% vs ï¼»71.21 ± 5.21ï¼½%, P < 0.05), but markedly increased after VE treatment (ï¼»60.68 ± 5.31ï¼½%, P < 0.05). CONCLUSIONS: Varicocele reduces the expression of the EETJ protein ZO-1 and impairs epididymal function via oxidative stress, while vitamin E can effectively upregulate the ZO-1 expression and improve epididymal function by decreasing oxidative stress in the epididymis of varicocele rats.


Assuntos
Epididimo/fisiopatologia , Estresse Oxidativo , Varicocele/fisiopatologia , Proteína da Zônula de Oclusão-1/metabolismo , Animais , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Motilidade dos Espermatozoides , Vitamina E/uso terapêutico
14.
Biochem Cell Biol ; 96(5): 572-579, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29390193

RESUMO

Aquaporin-5 (AQP5), a water channel protein, has been reported to possess oncogenic potential in multiple types of malignancies, including colorectal cancer (CRC). However, its effect on the chemosensitivity of CRC cells remains elusive. Hence, this study investigated the effect of AQP5 silencing in CRC cells on 5-fluorouracil (5-FU) sensitivity and attempted to elucidate the underlying mechanisms. A short hairpin RNA construct targeting AQP5 was transfected into HCT116 or HT29 cells to generate stable AQP5-silenced cell lines. The effects of AQP5 knockdown on cell viability, apoptosis, tumor growth, and 5-FU chemoresistance were evaluated. Relative protein levels of Wnt-ß-catenin pathway effectors were also measured. The results showed that silencing of AQP5 increased the chemosensitivity of CRC cells to 5-FU, facilitated 5-FU-mediated apoptosis, suppressed tumor growth, and reduced 5-FU chemoresistance in vivo. Furthermore, the effect of AQP5 on 5-FU chemosensitivity was mediated by the Wnt-ß-catenin pathway. Silencing of AQP5 inhibited Wnt-ß-catenin signaling, whereas overexpression of the degradation-resistant mutant of ß-catenin (S33Y) reversed apoptosis induced by AQP5 silencing. Taken together, these results suggest that AQP5 silencing enhances the sensitivity of CRC cells to 5-FU, and the underlying mechanism is related to inhibition of the Wnt-ß-catenin pathway. AQP5 could be a useful therapeutic target for CRC treatment.


Assuntos
Aquaporina 5/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fluoruracila/farmacologia , Proteínas de Neoplasias/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , Aquaporina 5/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Técnicas de Silenciamento de Genes , Células HCT116 , Células HT29 , Humanos , Proteínas de Neoplasias/genética , Via de Sinalização Wnt/genética , beta Catenina/genética , beta Catenina/metabolismo
15.
Med Sci Monit ; 24: 2864-2872, 2018 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-29748529

RESUMO

BACKGROUND The expression of aldehyde dehydrogenase 1A1 (ALDH1A1) is increased in several human tumors, including colorectal carcinoma (CRC). The aim of this study was to compare the expression ALDH1A1 in CRC tumor tissue compared with non-tumor adjacent tissue (NAT), using immunohistochemistry (IHC), and to determine whether the expression of the ALDH1A1 protein was associated with prognostic factors in CRC. MATERIAL AND METHODS Formalin-fixed paraffin-embedded (FFPE) tissue from 424 patients diagnosed with CRC, and 196 matched NATs were used to prepare tissue microarrays (TMAs). IHC was performed using an immunoperoxidase method with a primary polyclonal rabbit anti-ALDH1A1 antibody. The IHC scores by light microscopy were the staining intensity (scored from 0-3) multiplied by the percentage area of positive immunostaining within the visual field (scored from 0-4). Associations between tumor expression levels of ALDH1A1 and patient clinicopathological characteristics, including tumor grade, size, and TNM stage at surgery were analyzed. RESULTS ALDH1A1 protein expression was significantly increased in CRC tissues compared with matched NATs. In patients with CRC, increased expression of the ALDH1A1 protein was significantly associated with the presence of lymph node metastasis: 64.28% in N0 cases; 75.49% in N1 cases; and 82.14% in N2 cases, (P=0.002). Univariate and multivariate analysis showed that ALDH1A1 expression was an independent prognostic marker for CRC (P<0.001). CONCLUSIONS Using IHC, the expression of the ALDH1A1 protein in CRC tissues was significantly associated with the presence of lymph node metastases and might be a potential prognostic marker in patients with CRC.


Assuntos
Aldeído Desidrogenase/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/enzimologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Família Aldeído Desidrogenase 1 , Neoplasias Colorretais/patologia , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Retinal Desidrogenase
16.
Zygote ; 26(1): 24-32, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29239295

RESUMO

Somatic cell nuclear transfer (SCNT) is an important technique for life science research. However, most SCNT embryos fail to develop to term due to undefined reprogramming defects. Here, we show that abnormal Xi occurs in somatic cell NT blastocysts, whereas in female blastocysts derived from cumulus cell nuclear transfer, both X chromosomes were inactive. H3K27me3 removal by Kdm6a mRNA overexpression could significantly improve preimplantation development of NT embryos, and even reached a 70.2% blastocyst rate of cleaved embryos compared with the 38.5% rate of the control. H3K27me3 levels were significantly reduced in blastomeres from cloned blastocysts after overexpression of Kdm6a. qPCR indicated that rDNA transcription increased in both NT embryos and 293T cells after overexpression of Kdm6a. Our findings demonstrate that overexpression of Kdm6a improved the development of cloned mouse embryos by reducing H3K27me3 and increasing rDNA transcription.


Assuntos
Blastocisto/fisiologia , Regulação da Expressão Gênica no Desenvolvimento , Histona Desmetilases/genética , Lisina/metabolismo , Técnicas de Transferência Nuclear , Animais , Clonagem de Organismos/métodos , Células do Cúmulo/citologia , DNA Ribossômico/genética , Feminino , Células HEK293 , Histona Desmetilases/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Masculino , Camundongos Endogâmicos , Inativação do Cromossomo X
17.
Hum Mol Genet ; 24(5): 1441-56, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25480889

RESUMO

To investigate epigenetic contributions to Huntington's disease (HD) pathogenesis, we carried out genome-wide mapping of the transcriptional mark, trimethyl-histone H3-lysine 4 (H3K4me3) in neuronal nuclei extracted from prefrontal cortex of HD cases and controls using chromatin immunoprecipitation followed by deep-sequencing. Neuron-specific mapping of the genome-wide distribution of H3K4me3 revealed 136 differentially enriched loci associated with genes implicated in neuronal development and neurodegeneration, including GPR3, TMEM106B, PDIA6 and the Notch signaling genes hairy and enhancer of split 4 (HES4) and JAGGED2, supporting the view that the neuronal epigenome is affected in HD. Importantly, loss of H3K4me3 at CpG-rich sequences on the HES4 promoter was associated with excessive DNA methylation, reduced binding of nuclear proteins to the methylated region and altered expression of HES4 and HES4 targeted genes MASH1 and P21 involved in striatal development. Moreover, hypermethylation of HES4 promoter sequences was strikingly correlated with measures of striatal degeneration and age-of-onset in a cohort of 25 HD brains (r = 0.56, P = 0.006). Lastly, shRNA knockdown of HES4 in human neuroblastoma cells altered MASH1 and P21 mRNA expression and markedly increased mutated HTT-induced aggregates and cell death. These findings, taken together, suggest that epigenetic dysregulation of HES4 could play a critical role in modifying HD disease pathogenesis and severity.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Epigênese Genética , Proteínas de Homeodomínio/metabolismo , Doença de Huntington/genética , Neostriado/patologia , Adulto , Autopsia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Metilação de DNA , Feminino , Loci Gênicos , Marcadores Genéticos , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas de Homeodomínio/genética , Humanos , Masculino , Neostriado/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Filogenia , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Fatores de Transcrição HES-1
18.
Biochem Cell Biol ; 95(6): 628-633, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28746817

RESUMO

Bone marrow mesenchymal stem cells (BMSCs) have considerable therapeutic potential for the treatment of end-stage liver disease. Previous studies have demonstrated that BMSCs secrete growth factors and cytokines that inactivate hepatic stellate cells (HSCs), which inhibited the progression of hepatic fibrosis. The aim of this study was to determine the mechanism by which BMSCs suppress the function of HSCs in fibrosis. Our results showed that co-culture of BMSCs and HSCs induced cell cycle arrest at the G10/G1 phase and cell apoptosis of HSCs, which finally inhibited the cell proliferation of HSCs. Consistent with the cell cycle arrest, co-culture of BMSCs and HSCs increased the abundance of the cell cycle protein p27. Mechanistically, we further uncovered that following the co-culture with BMSCs, the expression level of the E3 ligase S-phase kinase-associated protein 2 (SKP2) that is responsible for the ubiquitination of p27 was decreased, which attenuated the ubiquitination of p27 and increased the stability of p27 in HSCs. Collectively, our results indicated the potential involvement of the SKP2-p27 axis for the inhibitory effect of BSMCs on the cell proliferation of HSCs.


Assuntos
Inibidor de Quinase Dependente de Ciclina p27/antagonistas & inibidores , Células Estreladas do Fígado/metabolismo , Células-Tronco Mesenquimais/metabolismo , Ubiquitinação , Apoptose , Proliferação de Células , Técnicas de Cocultura , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Voluntários Saudáveis , Humanos , Células-Tronco Mesenquimais/citologia
19.
J Surg Res ; 209: 1-7, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28032545

RESUMO

BACKGROUND: The management of acquired benign tracheoesophageal fistula (TEF) and bronchogastric stump fistula (BGSF) is a challenge. This study aimed to assess the "double-patch" technique with or without esophageal mucosa in treating nonmalignant TEF and BGSF. MATERIALS AND METHODS: We established a dog model with TEF by incising the esophageal and tracheal membranes and suturing them together. The dogs were divided into three groups (n = 12 per group). Groups A and B received a double-patch 7 d later. The esophageal mucosa of the patches was cauterized in the group A dogs, kept intact in group B dogs, and group C dogs did not receive surgical intervention. Tissue healing was measured using hydroxyproline levels. RESULTS: Morphologic and histopathologic changes of the esophagus were assessed by gross observation of the specimens, hematoxylin and eosin staining, tracheal stenosis index, and hydroxyproline levels. On day 56 after surgery, group A showed a tracheal stenosis index comparable with that of group C (0.140 ± 0.009 versus 0.138 ± 0.014, P = 1.00), whereas group B showed a higher stenosis index (0.170 ± 0.007) than group C (P = 0.029). The hydroxyproline levels were higher in group A than in B and C on day 7 (P = 0.029), and this difference was statistically significant on days 14 and 56 (all P < 0.001). CONCLUSIONS: The use of an esophageal "double-patch" technique without mucosa showed faster and more stable recovery than patches with mucosa in the repair of acquired nonmalignant complicated TEF and BGSF.


Assuntos
Fístula Brônquica/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Mucosa Esofágica/cirurgia , Fístula Gástrica/cirurgia , Fístula Traqueoesofágica/cirurgia , Animais , Cães , Hidroxiprolina/sangue
20.
Zhongguo Zhong Yao Za Zhi ; 42(12): 2373-2379, 2017 Jun.
Artigo em Zh | MEDLINE | ID: mdl-28822196

RESUMO

In order to reveal the properties of polar metabolome in inflammatory cells, we selected LPS-induced RAW264.7 inflammatory cell models as the carrier for the research of metabolic fingerprint analysis. In this study, an ultra performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS)-based metabolomics protocol was optimized for the extraction of polar metabolites from RAW264.7 cell line. Then orthogonal partial least squares discriminant analysis (OPLS-DA) was used to process the metabolic data, and finally, a total of 17 metabolites were selected and identified. The results showed that MeOH-CHCl3-H2O (8∶1∶1) was chosen as the optimal extraction solvent to achieve higher number of chromatographic peaks, with the best relative extraction efficiency and stability. Comparing with the normal cells, the inflammatory cells presented an abnormal metabolism in protein, carbohydrate, nucleotide and phospholipids. In this study, a UPLC-Q-TOF/MS-based metabolomics protocol for the polar metabolites from RAW264.7 cell line was developed, which may provide important information for the study of mechanism of inflammation and the anti-inflammatory drugs.


Assuntos
Macrófagos/metabolismo , Metabolômica , Animais , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Camundongos , Células RAW 264.7
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