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1.
Opt Express ; 32(10): 16746-16760, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38858873

RESUMO

Strong near-field enhancements (NFEs) of nanophotonic structures are believed to be closely related to high Purcell factors (FP). Here, we theoretically show that the correlation is partially correct; the extinction cross section (σ) response is also critical in determining FP. The divergence between NFE and FP is especially pronounced in plasmonic-dielectric hybrid systems, where the plasmonic antenna supports dipolar plasmon modes and the dielectric cavity hosts Mie-like resonances. The cavity's enhanced-field environment can boost the antenna's NFEs, but the FP is not increased concurrently due to the larger effective σ that is intrinsic to the FP calculations. Interestingly, the peak FP for the coupled system can be predicted by using the NFE and σ responses. Furthermore, the limits for FP of coupled systems are considered; they are determined by the sum of the FP of a redshifted (or modified, if applicable) antenna and an individual cavity. This contrasts starkly with the behavior of NFE which is closely associated with the multiplicative effects of the NFEs provided by the antenna and the dielectric cavity. The differing behaviors of NFE and FP in hybrid cavities have varied impacts on relevant nanophotonic applications such as fluorescence, Raman scattering and enhanced light-matter interactions.

2.
Acta Pharmacol Sin ; 44(10): 2004-2018, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37225844

RESUMO

Doxorubicin is a common chemotherapeutic agent in clinic, but myocardial toxicity limits its use. Fibroblast growth factor (FGF) 10, a multifunctional paracrine growth factor, plays diverse roles in embryonic and postnatal heart development as well as in cardiac regeneration and repair. In this study we investigated the role of FGF10 as a potential modulator of doxorubicin-induced cardiac cytotoxicity and the underlying molecular mechanisms. Fgf10+/- mice and an inducible dominant negative FGFR2b transgenic mouse model (Rosa26rtTA; tet(O)sFgfr2b) were used to determine the effect of Fgf10 hypomorph or blocking of endogenous FGFR2b ligands activity on doxorubicin-induced myocardial injury. Acute myocardial injury was induced by a single injection of doxorubicin (25 mg/kg, i.p.). Then cardiac function was evaluated using echocardiography, and DNA damage, oxidative stress and apoptosis in cardiac tissue were assessed. We showed that doxorubicin treatment markedly decreased the expression of FGFR2b ligands including FGF10 in cardiac tissue of wild type mice, whereas Fgf10+/- mice exhibited a greater degree of oxidative stress, DNA damage and apoptosis as compared with the Fgf10+/+ control. Pre-treatment with recombinant FGF10 protein significantly attenuated doxorubicin-induced oxidative stress, DNA damage and apoptosis both in doxorubicin-treated mice and in doxorubicin-treated HL-1 cells and NRCMs. We demonstrated that FGF10 protected against doxorubicin-induced myocardial toxicity via activation of FGFR2/Pleckstrin homology-like domain family A member 1 (PHLDA1)/Akt axis. Overall, our results unveil a potent protective effect of FGF10 against doxorubicin-induced myocardial injury and identify FGFR2b/PHLDA1/Akt axis as a potential therapeutic target for patients receiving doxorubicin treatment.


Assuntos
Fator 10 de Crescimento de Fibroblastos , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos , Animais , Camundongos , Doxorrubicina , Fator 10 de Crescimento de Fibroblastos/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais/fisiologia , Fatores de Transcrição
3.
Cell Immunol ; 381: 104611, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36194940

RESUMO

Herein, we show that profound afferent long-term peanut-allergen-specific IgE immunological tolerance for 3 to 9 months induced sustained unresponsiveness (SU) in naïve or peanut-sensitized rodents after peanut allergen immunization. Rodents were vaccinated sublingually with a peanut allergen extract or recombinant peanut allergen in chenodeoxycholate (CDCA), a fanesoid X receptor (FXR, NR1H4) agonist that downregulates SREBP-1c (sterol regulatory element binding protein-1c) and upregulates SHP in bone marrow-derived tolerogenic dendritic cells (DCs). Approximately 90 âˆ¼ 95 % of the total circulating PE-potentiated IgE and Ara h1, Ara h 2, and Ara h 6 peanut allergen-specific IgE responses were suppressed by recombinant peanut allergen-conjugated solid magnetic beads (sensitivity of 0.2 IU/ml). In contrast, peanut allergen-specific IgG production was not affected. Similarly, oleoylethanolamine (OEA), a peroxisome proliferator-activator receptor alpha (PPARα) agonist, and GW9662, a PPARγ antagonist, induced long-term peanut-specific IgE tolerance when administered via the sublingual, oral or i.p. route. Prophylactic Ara h2 DNA immunization with caNRF2 and IL-35 coexpression induced Ara h2 IgE tolerance. In summary, peanut allergen vaccination with select natural molecular ligands of nuclear receptors induced long-term peanut allergen-specific IgE tolerance via the afferent limb, which indicates that vaccination is an immune tolerance-promoting strategy that is effective at the DC level and that differs from Noon's daily desensitization program, which is effective at the mast cell level.

4.
Cytokine ; 149: 155729, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34673333

RESUMO

OBJECT: Goal of this research was to investigate values of serum cytokines in childhood HLH with different triggers, with the expectation to find secretion spectrum of 5 main types of underlying diseases. METHOD: 118 newly diagnosed HLH were included, and serum concentrations of 6 cytokines were tested before treatment began. Absolute cytokine levels and ratios between them were then studied in the HLH groups collectively and separately RESULTS: In general, IFN-γ, IL-10 and IL-6 showed differences among 5 HLH groups. Specifically, relative levels of these three cytokines to each other were meaningful in distinguishing 4 types of HLH. Level of IL-6 was higher than those of IFN-γ or IL-10 in HLH driven by Systemic auto-inflammatory disorders (SAIDs) or Langerhans Cell Histiocytosis (LCH), while primary HLH and EBV-HLH shared elevated ratio of IL-10 to IL-6. Although more than one distinctive ratios were found in 3 HLH groups, combination of these parameters didn't offer optimal balance between sensitivity and specificity. CONCLUSION: As a group of easily gained laboratory findings, cytokine levels were reliable in the procedure of roughly classifying HLH cases with the help of patients' clinical phenotype. However, adequate data is still needed to explore the significance of these indicators in identifying one particular underlying disease accurately.


Assuntos
Citocinas/sangue , Linfo-Histiocitose Hemofagocítica/sangue , Células Th1/metabolismo , Células Th2/metabolismo , Adolescente , Contagem de Células Sanguíneas/métodos , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Interferon gama/sangue , Interleucina-10/sangue , Interleucina-6/sangue , Masculino , Sensibilidade e Especificidade , Equilíbrio Th1-Th2/fisiologia
5.
Acta Pharmacol Sin ; 42(7): 1080-1089, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32939036

RESUMO

Duchenne muscular dystrophy (DMD) is a progressive neuromuscular disease caused by a mutation in the gene encoding the dystrophin protein. Catalpol is an iridoid glycoside found in Chinese herbs with anti-inflammatory, anti-oxidant, anti-apoptotic, and hypoglycemic activities that can protect against muscle wasting. In the present study we investigated the effects of catalpol on DMD. Aged Dystrophin-deficient (mdx) mice (12 months old) were treated with catalpol (100, 200 mg·kg-1·d-1, ig) for 6 weeks. At the end of the experiment, the mice were sacrificed, and gastrocnemius (GAS), tibialis anterior (TA), extensor digitorum longus (EDL), soleus (SOL) muscles were collected. We found that catalpol administration dose-dependently increased stride length and decreased stride width in Gait test. Wire grip test showed that the time of wire grip and grip strength were increased. We found that catalpol administration dose-dependently alleviated skeletal muscle damage, evidenced by reduced plasma CK and LDH activity as well as increased the weight of skeletal muscles. Catalpol administration had no effect on dystrophin expression, but exerted anti-inflammatory effects. Furthermore, catalpol administration dose-dependently decreased tibialis anterior (TA) muscle fibrosis, and inhibited the expression of TGF-ß1, TAK1 and α-SMA. In primary myoblasts from mdx mice, knockdown of TAK1 abolished the inhibitory effects of catalpol on the expression levels of TGF-ß1 and α-SMA. In conclusion, catalpol can restore skeletal muscle strength and alleviate skeletal muscle damage in aged mdx mice, thus may provide a novel therapy for DMD. Catalpol attenuates muscle fibrosis by inhibiting the TGF-ß1/TAK1 signaling pathway.


Assuntos
Glucosídeos Iridoides/uso terapêutico , Distrofia Muscular de Duchenne/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Animais , Fibrose/tratamento farmacológico , Fibrose/etiologia , Fibrose/patologia , Força da Mão/fisiologia , Inflamação/tratamento farmacológico , Inflamação/etiologia , Inflamação/patologia , MAP Quinase Quinase Quinases/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Distrofia Muscular de Duchenne/complicações , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/patologia , Fator de Crescimento Transformador beta1/metabolismo
6.
J Transl Med ; 18(1): 40, 2020 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-32000807

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is the most common type of liver tumour, and is closely related to liver cirrhosis. Previous studies have focussed on the pathogenesis of liver cirrhosis developing into HCC, but the molecular mechanism remains unclear. The aims of the present study were to identify key genes related to the transformation of cirrhosis into HCC, and explore the associated molecular mechanisms. METHODS: GSE89377, GSE17548, GSE63898 and GSE54236 mRNA microarray datasets from Gene Expression Omnibus (GEO) were analysed to obtain differentially expressed genes (DEGs) between HCC and liver cirrhosis tissues, and network analysis of protein-protein interactions (PPIs) was carried out. String and Cytoscape were used to analyse modules and identify hub genes, Kaplan-Meier Plotter and Oncomine databases were used to explore relationships between hub genes and disease occurrence, development and prognosis of HCC, and the molecular mechanism of the main hub gene was probed using Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway analysis. RESULTS: In total, 58 DEGs were obtained, of which 12 and 46 were up- and down-regulated, respectively. Three hub genes (CDKN3, CYP2C9 and LCAT) were identified and associated prognostic information was obtained. CDKN3 may be correlated with the occurrence, invasion, and recurrence of HCC. Genes closely related to changes in the CDKN3 hub gene were screened, and Kyoto Encyclopedia of Genes and Genomes (KEGGs) pathway analysis identified numerous cell cycle-related genes. CONCLUSION: CDKN3 may affect the transformation of liver cirrhosis into HCC, and represents a new candidate molecular marker of the occurrence and progression of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/genética , Biologia Computacional , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , Recidiva Local de Neoplasia
7.
Reprod Domest Anim ; 55(12): 1714-1724, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32969084

RESUMO

Boar sperm are susceptible to oxidative damage caused by reactive oxygen species (ROS) during storage. Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is an important therapeutic target, because it is a cellular metabolism energy sensor and key signalling kinase in spermatozoa. We evaluated the effects of rosmarinic acid (RA), an antioxidant, on boar sperm during liquid storage to determine whether it protects boar sperm via AMPK activation. Boar ejaculates were diluted with Modena extender with different concentrations of RA and stored at 17°C for 9 days. Sperm quality parameters, antioxidant capacity, energy metabolism, AMPK phosphorylation and fertility were analysed. Compared with the control, 40 µmol/L significantly improved sperm motility, plasma membrane integrity and acrosome integrity (p < .05). The effective storage time of boar sperm was up to 9 days. On the third and seventh days, the sperm with RA exhibited increased total antioxidant capacity (T-AOC), superoxide dismutase (SOD) activity, adenosine triphosphate (ATP) content, mitochondrial membrane potential (ΔΨm) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity, whereas malondialdehyde (MDA) content was significantly decreased (p < .05). Western blot showed that RA, as well as AICAR (AMPK activator), promoted AMPK phosphorylation, whereas Compound C (AMPK inhibitor) inhibited this effect. The sperm-zona pellucida binding experiment showed that 40 µmol/L RA increased the number of sperm attached to the zona pellucida (p < .05). These findings suggest meaningful methods for improved preservation of boar sperm in vitro and provide new insights into the mechanism by which RA protects sperm cells from oxidative damage via AMPK activation.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Cinamatos/farmacologia , Depsídeos/farmacologia , Preservação do Sêmen/veterinária , Sus scrofa , Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Metabolismo Energético , Masculino , Malondialdeído/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Análise do Sêmen/veterinária , Preservação do Sêmen/métodos , Espermatozoides/fisiologia , Ácido Rosmarínico
8.
Reproduction ; 157(2): 149-161, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30601756

RESUMO

Stress impacts the reproductive axis at the level of the hypothalamus and the pituitary gland, which exert an effect on the ovary. Menstruation is regulated by the hypothalamic-pituitary-ovary (HPO) axis. However, the role of stress in menstruation remains unclear. The objective of this study was to explore the role of stress in endometrial breakdown and shedding, using the pseudopregnant mouse menstrual-like model. Female mice were mated with vasectomized males and labeled day 0.5, upon observation of a vaginal seminal plug. On day 3.5, decidualization was induced in pseudopregnant mice using arachis oil. On day 5.5, pseudopregnant mice with artificial decidualization were placed in restraint tubes for 3 h. The findings indicated that acute restraint stress resulted in the disintegration of the endometrium. While corticosterone concentration in the serum increased significantly due to restraint stress, follicle-stimulating hormone (FSH), luteinizing hormone (LH) and progesterone (P4) levels in the serum decreased significantly. An endometrial histology examination indicated that progesterone implants may rescue P4 decline caused by acute stress and block endometrium breakdown and shedding. In addition, mice were treated with metyrapone, an inhibitor of corticosterone synthesis, 1 h prior to being subjected to restraint stress. Interestingly, metyrapone not only inhibited stress-induced endometrium breakdown and shedding, but also prevented stress-induced reduction of P4, LH and FSH. Furthermore, real-time PCR and western blot showed that mRNA and protein expression of CYP11A1 (cytochrome P450, family 11, subfamily A, polypeptide 1) and steroidogenic acute regulatory protein (StAR), the two rate-limiting enzymes for progesterone synthesis in the ovary, decreased following acute stress. But metyrapone prevented the reduction of StAR expression induced by restraint stress. Overall, this study revealed that acute stress results in an increase in corticosterone, which may inhibit LH and FSH release in the serum and CYP11A1 and StAR expression in the ovary, which finally leads to the breakdown and shedding of the endometrium. These experimental findings, based on the mouse model, may enable further understanding of the effects of stress on menstruation regulation and determine the potential factors affecting stress-associated menstrual disorders.


Assuntos
Corticosterona/sangue , Endométrio/patologia , Progesterona/sangue , Estresse Fisiológico/fisiologia , Estresse Psicológico/patologia , Animais , Endométrio/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Metirapona/farmacologia , Camundongos , Progesterona/farmacologia , Restrição Física
9.
Org Biomol Chem ; 17(13): 3462-3470, 2019 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-30888364

RESUMO

An organocatalytic chemo- and regioselective C6-functionalization of 2,3-disubstituted indoles has been established via a reaction with ortho-hydroxybenzyl alcohols, which afforded biologically important diarylindol-6-ylmethanes in overall high yields (up to 99% yield). This protocol not only provides an efficient method for constructing biologically important diarylindol-6-ylmethane frameworks in an atom economical fashion, but also serves as a good example for the direct catalytic C6-functionalization of indoles, which have been rarely investigated. More importantly, the preliminary biological evaluation revealed that this new class of diarylindol-6-ylmethanes exhibited strong cytotoxicity to HeLa cell lines.

10.
J Pharmacol Sci ; 140(3): 228-235, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31358372

RESUMO

Acute lung injury (ALI) results from various factors including uncontrolled pulmonary inflammation, oxidative damage and the over-activated complement with high mortality rates. Jaceosidin was a flavonoid compound with significant anti-complement activity. We aimed to investigate the therapeutic effects of Jaceosidin on ALI induced by lipopolysaccharide (LPS). Mice were orally administrated with Jaceosidin (15, 30 and 60 mg/kg) after LPS challenge. 24 h after LPS challenge, Jaceosidin could significantly decrease the lung wet-to-dry weight (W/D) ratio and the protein concentration in bronchoalveolar lavage fluid (BALF). Jaceosidin could down-regulate the levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1ß (IL-1ß), together with up-regulation the levels of interleukin-4 (IL-4) and interleukin-10 (IL-10) in BALF. Jaceosidin could significantly decrease the levels of myeloperoxidase (MPO), cyclooxygenase-2 (COX-2) and nuclear factor-κB (NF-κB), COX-2 mRNA and NF-κB p65 mRNA together with increasing the activity of catalase (CAT). Additionally, Jaceosidin attenuated lung histopathological changes, inhibited the expressions of COX-2 and NF-κB p65 and reduced complement deposition with decreasing the levels of complement 3 (C3) and complement 3c (C3c) in serum. These data suggest that Jaceocidin may dampen the inflammatory response and decrease the levels of complement together with the antioxidant activity following LPS-induced ALI.


Assuntos
Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Flavonoides/farmacologia , Lipopolissacarídeos/farmacologia , Lesão Pulmonar Aguda/metabolismo , Animais , Líquido da Lavagem Broncoalveolar/química , Ciclo-Oxigenase 2/metabolismo , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Peroxidase/metabolismo , Extratos Vegetais/farmacologia , Pneumonia/tratamento farmacológico , Pneumonia/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
11.
Oecologia ; 186(3): 793-803, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29344733

RESUMO

The importance of intraspecific trait variability (ITV) to the spatial distribution of individual species is unclear. We hypothesized that intraspecific trait dispersions underlying niche processes deviate more from null model expectations, by reducing their spread (range and variance), kurtosis, and standard deviation of near-neighbor distance, for species with aggregated than those with random distributions. The link between species' spatial distributions and ITV patterns was examined using an individual tree-based trait data set, in which specific leaf area, mean leaf area, leaf dry matter content, and diameter at breast height were measured for 18,773 stems of 45 species in a 4.84 ha mapped subtropical forest plot in China. The nearest-neighbor distance analysis showed that, of 45 species, 14 species were distributed in random and 31 species were distributed in aggregation, while no species was distributed in uniform in the plot. The dispersions of all studied traits in species with an aggregated distribution on average deviated more strongly from the null expectation than those in species with a random distribution and that the extent of deviation was negatively associated with the degree of spatial randomness across species. Our results indicate that niche processes are primarily responsible for the spatial structure of species with aggregated distributions, while stochastic processes drive those with random distributions. Our results highlight the fundamental role of ITV in shaping spatial patterns of co-existing species.


Assuntos
Florestas , Folhas de Planta , China , Fenótipo
12.
Future Oncol ; 14(20): 2005-2011, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29513033

RESUMO

AIM: To explore the association between the determinant factors including HLA-DQB1*03, DRB1-*07, -*13 and high-risk HPV infection, the cervical squamous cell carcinoma (CSCC) pathogenesis among Chinese Uighur and Han population. MATERIALS & METHODS: HLA alleles were genotyped by PCR sequence-specific primers. RESULTS: HPV16 infection rate was significantly higher among the Uighurs and Hans with CSCC as compared with healthy controls, respectively. HLA-DQB1*03 significantly increased among Uighurs with CSCC, while HLA-DRB1*07 significantly increased among Hans with CSCC. Similar tendencies were observed for DQB1*03 with HPV16-positive Uighurs CSCC and DRB1*07 with HPV16-positive Hans CSCC. CONCLUSION: This study suggests that HLA-DQB1*03 and DRB1*07 alleles may influence the immune response to HPV16 infection and increase the risk of CSCC among the Uighurs and Hans in China.


Assuntos
Alelos , Etnicidade/genética , Predisposição Genética para Doença , Cadeias beta de HLA-DQ/genética , Neoplasias do Colo do Útero/genética , Adulto , Idoso , China/epidemiologia , Feminino , Papillomavirus Humano 16 , Humanos , Pessoa de Meia-Idade , Razão de Chances , Infecções por Papillomavirus/virologia , Medição de Risco , Análise de Sequência de DNA , Neoplasias do Colo do Útero/virologia , Adulto Jovem
13.
Indian J Microbiol ; 58(4): 440-447, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30262954

RESUMO

A wild-type strain was isolated from slightly rotted pears after three rounds of enrichment culture, identified as Saccharomyces cerevisiae 3308, and evaluated for its fermentation capability of second generation bioethanol and tolerance of temperature, glucose and ethanol. S. cerevisiae 3308 was mutated by using the physical and chemical mutagenesis methods, ultraviolet (UV) and diethyl sulfate (DES), respectively. Positive mutated strains were mainly generated by the treatment of UV, but numerous negative mutations emerged under the treatment of DES. A positive mutated strain, UV-20, produced ethanol from 62.33 ± 1.34 to 122.22 ± 2.80 g/L at 30-45 °C, and had a maximum yield of ethanol at 37 °C. Furthermore, UV-20 produced 121.18 ± 2.51 g/L of second generation bioethanol at 37 °C. Simultaneously, UV-20 exhibited superior tolerance to 50% of glucose and 21% of ethanol. In a conclusion, all of these results indicated that UV-20 has a potential industrial application value.

14.
Neurochem Res ; 42(6): 1847-1863, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28478595

RESUMO

Cell migration is identified as a highly orchestrated process. It is a fundamental and essential phenomenon underlying tissue morphogenesis, wound healing, and immune response. Under dysregulation, it contributes to cancer metastasis. Brain is considered to be the most complex organ in human body containing many types of neural cells with astrocytes playing crucial roles in monitoring both physiological and pathological functions. Astrocytoma originates from astrocytes and its most malignant type is glioblastoma multiforme (WHO Grade IV astrocytoma), which is capable to infiltrate widely into the neighboring brain tissues making a complete resection of tumors impossible. Very recently, we have reviewed the mechanisms for astrocytes in migration. Given the fact that astrocytoma shares many histological features with astrocytes, we therefore attempt to review the mechanisms for glioma cells in migration and compare them to normal astrocytes, hoping to obtain a better insight into the dysregulation of migratory mechanisms contributing to their metastasis in the brain.


Assuntos
Neoplasias Encefálicas/patologia , Encéfalo/patologia , Movimento Celular/fisiologia , Glioma/patologia , Animais , Astrócitos/patologia , Encéfalo/metabolismo , Encéfalo/cirurgia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/cirurgia , Glioma/metabolismo , Glioma/cirurgia , Humanos
15.
Neurochem Res ; 42(1): 272-282, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27837318

RESUMO

Cell migration is a fundamental phenomenon that underlies tissue morphogenesis, wound healing, immune response, and cancer metastasis. Great progresses have been made in research methodologies, with cell migration identified as a highly orchestrated process. Brain is considered the most complex organ in the human body, containing many types of neural cells with astrocytes playing crucial roles in monitoring normal functions of the central nervous system. Astrocytes are mostly quiescent under normal physiological conditions in the adult brain but become migratory after injury. Under most known pathological conditions in the brain, spinal cord and retina, astrocytes are activated and become hypertrophic, hyperplastic, and up-regulating GFAP based on the grades of severity. These three observations are the hallmark in glia scar formation-astrogliosis. The reactivation process is initiated with structural changes involving cell process migration and ended with cell migration. Detailed mechanisms in astrocyte migration have not been studied extensively and remain largely unknown. Here, we therefore attempt to review the mechanisms in migration of astrocytes.


Assuntos
Astrócitos/metabolismo , Movimento Celular/fisiologia , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Adesão Celular/fisiologia , Células Cultivadas , Humanos , Medula Espinal/citologia , Medula Espinal/metabolismo
16.
Sheng Li Xue Bao ; 69(5): 703-714, 2017 Oct 25.
Artigo em Zh | MEDLINE | ID: mdl-29063118

RESUMO

DREAM (downstream regulatory element antagonist modulator), Calsenilin and KChIP3 (potassium channel interacting protein 3) belong to the neuronal calcium sensor (NCS) superfamily, which transduces the intracellular calcium signaling into a variety of activities. They are encoded by the same gene locus, but have distinct subcellular locations. DREAM was first found to interact with DRE (downstream regulatory element) site in the vicinity of the promoter of prodynorphin gene to suppress gene transcription. Calcium can disassemble this interaction by binding reversibly to DREAM protein on its four EF-hand motifs. Apart from having calcium dependent DRE site binding, DREAM can also interact with other transcription factors, such as cAMP responsive element binding protein (CREB), CREB-binding protein (CBP) and cAMP responsive element modulator (CREM), by this concerted actions, DREAM extends the gene pool under its control. DREAM is predominantly expressed in central nervous system with its highest level in cerebellum, and accumulating evidence demonstrated that DREAM might play important roles in pain sensitivity. Novel findings have shown that DREAM is also involved in learning and memory processes, Alzheimer's disease and stroke. This mini-review provides a brief introduction of its discovery history and protein structure properties, focusing on the mechanism of DREAM nuclear translocation and gene transcription regulation functions.


Assuntos
Regulação da Expressão Gênica , Proteínas Interatuantes com Canais de Kv/fisiologia , Proteínas Repressoras/fisiologia , Animais , Sinalização do Cálcio/fisiologia , Humanos , Proteínas Interatuantes com Canais de Kv/genética , Limiar da Dor , Proteínas Repressoras/genética
17.
Genet Res (Camb) ; 98: e14, 2016 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-27834158

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is a primary liver malignancy that mainly occurs in patients with chronic liver disease and cirrhosis. Risk factors for HCC include hepatitis B virus (HBV) infection. However, the specific role of HBV infection in HCC development is not yet completely understood. In order to reveal the effects of HBV on HCC, we compare the genes of HCC patients infected with HBV with those who are not infected. METHODS: We encoded the genes of these two types of HCC in databases using enrichment scores of Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway terms. A random forest algorithm was employed in order to distinguish these two types in the classifier, and a series of feature selection approaches was used in order to select their optimal features. Novel HBV-associated and -non-associated HCC genes were predicted, respectively, based on their optimal features in the classifier. A shortest-path algorithm was also employed in order to find all of the shortest-paths genes connecting the known related genes. RESULTS: A total of 54 different features between HBV-associated and -non-associated HCC genes were identified. In total, 1236 and 881 novel related genes were predicted for HBV-associated and -non-associated HCC, respectively. By integrating the predicted genes and shortest path genes in their gene interaction network, we identified 679 common genes involved in the two types of HCC. CONCLUSION: We identified the significantly different genetic features between two types of HCC. We also predicted related genes for the two types based on their specific features. Finally, we determined the common genes and features that were involved in both of these two types of HCC.


Assuntos
Biomarcadores/análise , Carcinoma Hepatocelular/genética , Vírus da Hepatite B/genética , Hepatite B/complicações , Neoplasias Hepáticas/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Estudos de Casos e Controles , Hepatite B/genética , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Reação em Cadeia da Polimerase em Tempo Real
18.
J Neurosci Res ; 93(10): 1507-18, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25711139

RESUMO

Stroke is a leading cause of death and disability, and new strategies are required to reduce neuronal injury and improve prognosis. Ischemia preconditioning (IPC) is an intrinsic phenomenon that protects cells from subsequent ischemic injury and might provide promising mechanisms for clinical treatment. In this study, primary astrocytes exhibited significantly less cell death than control when exposed to different durations of IPC (15, 30, 60, or 120 min). A 15-min duration was the most effective IPC to protect astrocytes from 8-hr-ischemia injury. The protective mechanisms of IPC involve the upregulation of protective proteins, including 14-3-3γ, and attenuation of malondialdehyde (MDA) content and ATP depletion. 14-3-3γ is an antiapoptotic intracellular protein that was significantly upregulated for up to 84 hr after IPC. In addition, IPC promoted activation of the c-Jun N-terminal kinase (JNK), extracellular signal-related kinase (ERK)-1/2, p38, and protein kinase B (Akt) signaling pathways. When JNK was specifically inhibited with SP600125, the upregulation of 14-3-3γ induced by IPC was almost completely abolished; however, there was no effect on ATP or MDA levels. This suggests that, even though both energy preservation and 14-3-3γ up-regulation were turned on by IPC, they were controlled by different pathways. The ERK1/2, p38, and Akt signaling pathways were not involved in the 14-3-3γ upregulation and energy preservation. These results indicate that IPC could protect astrocytes from ischemia injury by inducing 14-3-3γ and by alleviating energy depletion through different pathways, suggesting multiple protection of IPC and providing new insights into potential stroke therapies.


Assuntos
Proteínas 14-3-3/metabolismo , Astrócitos/metabolismo , Regulação da Expressão Gênica/fisiologia , Precondicionamento Isquêmico , Transdução de Sinais/fisiologia , Regulação para Cima/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Contagem de Células , Morte Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Células Cultivadas , Córtex Cerebral/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Isquemia/prevenção & controle , L-Lactato Desidrogenase/metabolismo , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo
19.
Neurochem Res ; 40(9): 1929-44, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26248512

RESUMO

Cadmium (Cd), a highly ubiquitous toxic heavy metal, can contaminate the environment, including agricultural soil, water and air, via industrial runoff and other sources of pollution. Cd accumulated in the body via direct exposure or through the food chain results in neurodegeneration and many other diseases. Previous studies on its toxicity in the central nervous system (CNS) focused mainly on neurons. To obtain a more comprehensive understanding of Cd toxicity for the CNS, we investigated how astrocytes respond to acute and chronic Cd exposure and its toxic molecular mechanisms. When primary cultures of cerebral cortical astrocytes incubated with 1-300 µM CdCl2, morphological changes, LDH release and cell death were observed in a time and dose-dependent manner. Further studies demonstrated that acute and chronic Cd treatment phosphorylated JNK, p38 and Akt to different degrees, while ERK1/2 was only phosphorylated under low doses of Cd (10 µM) exposure. Inhibition of JNK and PI3K/Akt, but not of p38, could partially protect astrocyte from cytotoxicity in chronic and acute Cd exposure. Moreover, Cd also induced a strong calcium signal, while BAPTA, a specific intracellular calcium (Ca(2+)) chelator, prevented Cd-induced intracellular increase of calcium levels in astrocytes; inhibited the Cd-induced activation of ERK1/2, JNK, p38 and Akt; and also significantly reduced astrocyte cell death. All of these results suggested that the Cd-Ca(2+)-MAPK and PI3K/Akt signaling pathways were involved in Cd-induced toxicity in astrocytes. This toxicity involvement indicates that these pathways may be exploited as a target for the prevention of Cd-induced neurodegenerative diseases.


Assuntos
Astrócitos/efeitos dos fármacos , Cádmio/toxicidade , Sinalização do Cálcio , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Animais , Astrócitos/enzimologia , Relação Dose-Resposta a Droga , Camundongos , Camundongos Endogâmicos ICR
20.
Tumour Biol ; 35(2): 967-71, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24006221

RESUMO

Recently, it has been reported that tazarotene-induced gene 1 (TIG1) methylation was frequently detected in a variety of human cancers. However, the relationship between the TIG1 methylation and the characteristics of hepatocellular carcinoma (HCC) remains unknown. The aim of present study was to observe the promoter methylation of TIG1 in HCC tissues and assess its prognostic significance for HCC. Real-time quantitative polymerase chain reaction and methylation-specific polymerase chain reaction were used, respectively, to examine the mRNA expression and methylation status of TIG1 in 91 pairs of HCC and adjacent noncancerous tissues. The mRNA expression level of TIG1 was significantly lower in HCC tissues than in adjacent noncancerous tissues. The rate of TIG1 promoter methylation was significantly higher in HCC tissues than in adjacent noncancerous tissues (P < 0.001). A strong correlation between downregulation and promoter methylation was found in these tumors (P < 0.001). More importantly, TIG1 methylation status was related to tumor size (P = 0.015), histological differentiation (P = 0.004), and tumor stage (P < 0.001). Kaplan-Meier survival analysis showed that TIG1 promoter hypermethylation was associated with a worse outcome in patients with HCC. Further, Cox multivariate analysis indicated that TIG1 methylation status was an independent prognostic factor for the overall survival rate of HCC patients. In conclusion, our data suggested that epigenetic silencing of TIG1 gene expression by promoter hypermethylation may play an important role in HCC.


Assuntos
Carcinoma Hepatocelular/genética , Metilação de DNA/genética , Neoplasias Hepáticas/genética , Proteínas de Membrana/genética , Adulto , Idoso , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/patologia , Regulação para Baixo , Epigênese Genética/genética , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Regiões Promotoras Genéticas
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