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1.
Pharmacol Res ; 161: 105218, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33007418

RESUMO

Endoplasmic reticulum (ER) stress is easily observed in chronic liver disease, which often causes accumulation of unfolded or misfolded proteins in the ER, leading to unfolded protein response (UPR). Regulating protein degradation is an integral part of UPR to relieve ER stress. The major protein degradation system includes the ubiquitin-proteasome system (UPS) and autophagy. All three arms of UPR triggered in response to ER stress can regulate UPS and autophagy. Accumulated misfolded proteins could activate these arms, and then generate various transcription factors to regulate the expression of UPS-related and autophagy-related genes. The protein degradation process regulated by UPR has great significance in many chronic liver diseases, including non-alcoholic fatty liver disease (NAFLD), alcoholic liver disease (ALD), viral hepatitis, liver fibrosis, and hepatocellular carcinoma(HCC). In most instances, the degradation of excessive proteins protects cells with ER stress survival from apoptosis. According to the specific functions of protein degradation in chronic liver disease, choosing to promote or inhibit this process is promising as a potential method for treating chronic liver disease.


Assuntos
Estresse do Retículo Endoplasmático , Hepatopatias/metabolismo , Fígado/metabolismo , Proteostase , Animais , Autofagia , Doença Crônica , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Hepatopatias/tratamento farmacológico , Hepatopatias/patologia , Proteólise , Proteostase/efeitos dos fármacos , Resposta a Proteínas não Dobradas
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 349-54, 2016 Feb.
Artigo em Zh | MEDLINE | ID: mdl-27209729

RESUMO

In accordance with the one-step synthesis, in this paper, we synthesized 510, 550 and 630 nm three emission peaks CdSe/ZnS core-shell quantum dots with high stability and high quantum yield whose quantum yield were 82%, 98% and 97%. We used the quantum dot material to replace the phosphor material, and mixed QDs with the silicone uniformly, then dispersed the QDs/silicone composites onto the blue InGaN LEDs to fabricate the QDs-WLEDs. By successively adding different colors of quantum dots for the preparation of quantum dot light converting layer, We investigated that how does the ratio of the three kind of quantum dots whose peaks were 510, 550 and 630 nm effect on the properties of the white LED devices. This paper also studied the mechanism of energy conversion between different colors of quantum dots. We also utilized the mechanism that the quantum dots effect on the white spectrum and color coordinates; we got the results of the optimization of the white device and the ratio of three-color quantum dots. The results show that when the quantum dot ratio is 24:7:10, white LED devices with high stability and high efficiency can be obtained, in the current range of 20-200 mA, the range of color temperature is from 4 607 to 5 920 K, the CIE-1931 coordinates is from (0.355 1,0.348 3) to (0.323 4, 0.336 1), the color rendering index is from 77. 6 to 84. 2, and the highest power efficiency of the devices achieves to 31.69 lm · W⁻¹ @ 20 mA. In addition, in order to further investigate the reason of stable device performance, We studied the effects of time, temperature, UV treatment on the stability of CdSe/ZnS QDs/silicone light conversion material, the results show that the excellent stability of the devices attributes to the stability of the one-step synthesis of core-shell structure of the quantum dot material, the final optimized device is a low-power high-quality white light source and the device has good application prospects in the field of standard white light source which can truly perceive the color and original features of objects.

3.
Am J Physiol Renal Physiol ; 306(6): F672-80, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24477681

RESUMO

Mutations in the electrogenic Na(+)/HCO3(-) cotransporter (NBCe1) that cause proximal renal tubular acidosis (pRTA), glaucoma, and cataracts in patients are recessive. Parents and siblings of these affected individuals seem asymptomatic although their tissues should make some mutant NBCe1 protein. Biochemical studies with AE1 and NBCe1 indicate that both, and probably all, Slc4 members form dimers. However, the physiologic implications of dimerization have not yet been fully explored. Here, human NBCe1A dimerization is demonstrated by biomolecular fluorescence complementation (BiFC). An enhanced yellow fluorescent protein (EYFP) fragment (1-158, EYFP(N)) or (159-238, EYFP(C)) was fused to the NH2 or COOH terminus of NBCe1A and mix-and-matched expressed in Xenopus oocyte. The EYFP fluorescent signal was observed only when both EYFP fragments are fused to the NH2 terminus of NBCe1A (EYFP(N)-N-NBCe1A w/ EYFP(C)-N-NBCe1A), and the electrophysiology data demonstrated this EYFP-NBCe1A coexpressed pair have wild-type transport function. These data suggest NBCe1A forms dimers and that NH2 termini from the two monomers are in close proximity, likely pair up, to form a functional unit. To explore the physiologic significance of NBCe1 dimerization, we chose two severe NBCe1 mutations (6.6 and 20% wild-type function individually): S427L (naturally occurring) and E91R (for NH2-terminal structure studies). When we coexpressed S427L and E91R, we measured 50% wild-type function, which can only occur if the S427L-E91R heterodimer is the functional unit. We hypothesize that the dominant negative effect of heterozygous NBCe1 carrier should be obvious if the mutated residues are structurally crucial to the dimer formation. The S427L-E91R heterodimer complex allows the monomers to structurally complement each other resulting in a dimer with wild-type like function.


Assuntos
Multimerização Proteica , Simportadores de Sódio-Bicarbonato/genética , Acidose Tubular Renal/genética , Acidose Tubular Renal/metabolismo , Animais , Proteínas de Bactérias/química , Humanos , Proteínas Luminescentes/química , Microscopia de Fluorescência/métodos , Simportadores de Sódio-Bicarbonato/química , Xenopus
4.
Plant Cell Physiol ; 55(1): 148-61, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24214268

RESUMO

Examination of aquaporin (AQP) membrane channels in extremophile plants may increase our understanding of plant tolerance to high salt, drought or other conditions. Here, we cloned a tonoplast AQP gene (TsTIP1;2) from the halophyte Thellungiella salsuginea and characterized its biological functions. TsTIP1;2 transcripts accumulate to high levels in several organs, increasing in response to multiple external stimuli. Ectopic overexpression of TsTIP1;2 in Arabidopsis significantly increased plant tolerance to drought, salt and oxidative stresses. TsTIP1;2 had water channel activity when expressed in Xenopus oocytes. TsTIP1;2 was also able to conduct H2O2 molecules into yeast cells in response to oxidative stress. TsTIP1;2 was not permeable to Na(+) in Xenopus oocytes, but it could facilitate the entry of Na(+) ions into plant cell vacuoles by an indirect process under high-salinity conditions. Collectively, these data showed that TsTIP1;2 could mediate the conduction of both H2O and H2O2 across membranes, and may act as a multifunctional contributor to survival of T. salsuginea in highly stressful habitats.


Assuntos
Aquaporinas/metabolismo , Brassicaceae/fisiologia , Estresse Fisiológico , Vacúolos/metabolismo , Animais , Arabidopsis/genética , Arabidopsis/fisiologia , Transporte Biológico/efeitos dos fármacos , Brassicaceae/efeitos dos fármacos , Brassicaceae/genética , Clonagem Molecular , Difusão , Secas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas/genética , Proteínas de Fluorescência Verde/metabolismo , Peróxido de Hidrogênio/metabolismo , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Filogenia , Plantas Geneticamente Modificadas , Transporte Proteico/efeitos dos fármacos , Sódio/metabolismo , Cloreto de Sódio/farmacologia , Estresse Fisiológico/efeitos dos fármacos , Estresse Fisiológico/genética , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo , Vacúolos/efeitos dos fármacos , Água/metabolismo , Xenopus
5.
Zhongguo Zhong Yao Za Zhi ; 39(6): 959-64, 2014 Mar.
Artigo em Zh | MEDLINE | ID: mdl-24956833

RESUMO

To determine the genetic diversity of Haloxylon ammodendron collected from 14 sites in 5 provinces, 103 H. ammodendron samples of 12 wild populations and 2 cultivated which collected from 14 sites in 5 provinces were analyzed by amplified fragment length polymorphism (AFLP) DNA markers. PopGen32 and NTSYSpc2.1 was applied to evaluate genetic diversity of H. ammodendron populations. The average percentage of polymorphic loci (PPL) of total H. ammodendron populations was 94.13%, the average Nei's gene diversity index (H(e)) from 14 populations was 0.308 0, and the Shannon's genetic diversity index (I) was 0.467 6. The results indicated that the genetic diversity of H. ammodendron populations was high. Genetic differentiation index (G(st)) was 0.313 8, and the gene flow (N(m)) was 1.093 5 at the population level. The level of gene flow of H. ammodendron showed it possessed the feature of wind-pollinated outcrossing plants. AMOVA analysis indicated that genetic variation of H. ammodendron was much higher within groups (89.34%) than that among groups (10.66%), moreover genetic variation within groups mainly occurred among populations in different producing areas (84.80%). Cluster analysis (UPGMA) was applied to generate dendrogram based on Nei's genetic distances of 14 populations. Samples from Xinjiang and Qinghai were clustered respectively as a clade for their distant genetic relationship, while Samples from Gansu, Inner Mongolia and Ningxia were clustered together for their close genetic relationship. Genetic diversity of H. ammodendron populations is high in China, and genetic differentiation among regions is small, thus abundance within this specie is high at this stage. Therefore, wild nursery and artificial cultivating in different areas are effective measures for the conservation and sustainable utilization of H. ammodendron resources.


Assuntos
Amaranthaceae/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Variação Genética , China , Evolução Molecular , Filogenia
6.
PLoS One ; 19(4): e0292726, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38573879

RESUMO

BACKGROUND: The long non-coding RNA cancer susceptibility candidate (CASC) has abnormal expression in lung cancer tissues and may correlate with lung cancer prognosis. This study aimed to comprehensively evaluate the association between CASC expression and the cancer prognosis. METHODS: PubMed, Embase, Web of Science, Google Scholar, Cochrane Library, and China National Knowledge Infrastructure databases were searched until April 1, 2023, to obtain the relevant literature. Studies that met the predefined eligibility criteria were included, and their quality was independently assessed by 2 investigators according to the Newcastle-Ottawa Scale (NOS) score. Detailed information was obtained, such as first author, year of publication, and number of patients. Hazard ratio (HR) with a 95% confidence interval (CI) was extracted and grouped to assess the relationship between CASC expression and cancer prognosis. The dichotomous data was merged and shown as the odds ratio (OR) with a 95% CI was extracted to assess the relationship between CASC expression and clinicopathological parameters. RESULTS: A total of 12 studies with 746 patients with lung cancer were included in the meta-analysis. The expression levels of lncRNA CASC2 and CASC7 were decreased, while those of CASC9, 11, 15, and 19 were induced in lung cancer tissues compared with paracancerous tissues. In the population with low CASC expression (CASC2 and CASC7), high CASC expression indicated a good lung cancer prognosis (HR = 0.469; 95% CI, 0.271-0.668). Conversely, in the population with high CASC expression (CASC9, 11, 15, and 19), high CASC expression predicted a poor lung cancer outcome (HR = 1.910; 95% CI, 1.628-2.192). High CASC expression also predicted worse disease-free survival (DFS) (HR = 2.803; 95% CI, 1.804-6.319). Combined OR with 95% CI revealed an insignificant positive association between high CASC expression and advanced TNM stage (OR = 1.061; 95% CI, 0.775-1.454), LNM (OR = 0.962; 95% CI, 0.724-1.277), tumor size (OR = 0.942; 95% CI, 0.667-1.330), and histological grade (OR = 1.022; 95% CI, 0.689-1.517). CONCLUSION: The CASC expression levels negatively correlate with lung cancer prognosis. Therefore, CASC expression may serve as a prognostic marker and a potential therapeutic target for lung cancer.


Assuntos
Neoplasias Pulmonares , Neoplasias , RNA Longo não Codificante , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias/patologia , Prognóstico , Modelos de Riscos Proporcionais , Intervalo Livre de Doença , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Biomarcadores Tumorais/genética
7.
Commun Biol ; 7(1): 408, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570609

RESUMO

The regressive evolution of independent lineages often results in convergent phenotypes. Several teleost groups display secondary loss of the stomach, and four gastric genes, atp4a, atp4b, pgc, and pga2 have been co-deleted in agastric (stomachless) fish. Analyses of genotypic convergence among agastric fishes showed that four genes, slc26a9, kcne2, cldn18a, and vsig1, were co-deleted or pseudogenized in most agastric fishes of the four major groups. kcne2 and vsig1 were also deleted or pseudogenized in the agastric monotreme echidna and platypus, respectively. In the stomachs of sticklebacks, these genes are expressed in gastric gland cells or surface epithelial cells. An ohnolog of cldn18 was retained in some agastric teleosts but exhibited an increased non-synonymous substitution when compared with gastric species. These results revealed novel convergent gene losses at multiple loci among the four major groups of agastric fish, as well as a single gene loss in the echidna and platypus.


Assuntos
Ornitorrinco , Tachyglossidae , Animais , Filogenia , Ornitorrinco/genética , Tachyglossidae/genética , Estômago , Peixes/genética
8.
Am J Physiol Regul Integr Comp Physiol ; 304(10): R865-76, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23485868

RESUMO

Na(+)/H(+) exchanger 3 (NHE3) provides one of the major Na(+) absorptive pathways of the intestine and kidney in mammals, and recent studies of aquatic vertebrates (teleosts and elasmobranchs) have demonstrated that NHE3 is expressed in the gill and plays important roles in ion and acid-base regulation. To understand the role of NHE3 in elasmobranch osmoregulatory organs, we analyzed renal and intestinal expressions and localizations of NHE3 in a marine elasmobranch, Japanese banded houndshark (Triakis scyllium). mRNA for Triakis NHE3 was most highly expressed in the gill, kidney, spiral intestine, and rectum. The kidney and intestine expressed a transcriptional isoform of NHE3 (NHE3k/i), which has a different amino terminus compared with that of NHE3 isolated from the gill (NHE3g), suggesting that NHE3k/i and NHE3g arise from a single gene by alternative promoter usage. Immunohistochemical analyses of the Triakis kidney demonstrated that NHE3k/i is expressed in the apical membrane of a part of the proximal and late distal tubules in the sinus zone. In the bundle zone of the kidney, NHE3k/i was expressed in the apical membrane of the early distal tubules known as the diluting segment. In the spiral intestine and rectum, NHE3k/i was localized toward the apical membrane of the epithelial cells. The transcriptional levels of NHE3k/i were increased in the kidney when Triakis was acclimated in 130% seawater, whereas those in the spiral intestine were increased in fish acclimated in diluted seawater. These results suggest that NHE3 is involved in renal Na(+) reabsorption, urine acidification, and intestinal Na(+) absorption in elasmobranchs.


Assuntos
Mucosa Intestinal/metabolismo , Rim/metabolismo , Isoformas de Proteínas/metabolismo , Tubarões/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Animais , Transporte de Íons/fisiologia , Regiões Promotoras Genéticas , Isoformas de Proteínas/genética , Tubarões/genética , Trocador 3 de Sódio-Hidrogênio , Trocadores de Sódio-Hidrogênio/genética , Equilíbrio Hidroeletrolítico/fisiologia
9.
Hum Mutat ; 33(8): 1275-84, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22544634

RESUMO

Slc26 anion transporters play crucial roles in transepithelial Cl(-) absorption and HCO(3)(-) secretion; Slc26 protein mutations lead to several diseases. Slc26a9 functions as a Cl(-) channel and electrogenic Cl(-)--HCO(3)(-) exchanger, and can interact with cystic fibrosis transmembrane conductance regulator. Slc26a9(-/-) mice have reduced gastric acid secretion, yet no human disease is currently associated with SLC26A9 coding mutations. Therefore, we tested the function of nonsynonymous, coding, single nucleotide polymorphisms (cSNPs) of SLC26A9. Presently, eight cSNPs are NCBI documented: Y70N, T127N, I384T, R575W, P606L, V622L, V744M, and H748R. Using two-electrode voltage-clamp and anion selective electrodes, we measured the biophysical consequences of these cSNPs. Y70N (cytoplasmic N-terminus) displays higher channel activity and enhanced Cl(-)--HCO(3)(-) exchange. T127N (transmembrane) results in smaller halide currents but not for SCN(-). V622L (STAS domain) and V744M (STAS adjacent) decreased plasma membrane expression, which partially accounts for decreased whole cell currents. Nevertheless, V622L transport is reduced to ∼50%. SLC26A9 polymorphisms lead to several function modifications (increased activity, decreased activity, altered protein expression), which could lead to a spectrum of pathophysiologies. Thus, knowing an individual's SLC26A9 genetics becomes important for understanding disease potentially caused by SLC26A9 mutations or modifying diseases, for example, cystic fibrosis. Our results also provide a framework to understand SLC26A9 transport modalities and structure-function relationships.


Assuntos
Antiporters/genética , Polimorfismo de Nucleotídeo Único/genética , Animais , Biotinilação , Eletrofisiologia , Feminino , Humanos , Mutagênese Sítio-Dirigida , Oócitos/metabolismo , Transportadores de Sulfato , Xenopus laevis
10.
Clin Rheumatol ; 41(2): 437-452, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34553293

RESUMO

BACKGROUND: Lupus erythematosus is an autoimmune disease that causes damage to multiple organs ranging from skin lesions to systemic manifestations. Cutaneous lupus erythematosus (CLE) is a common type of lupus erythematosus (LE), but its molecular mechanisms are currently unknown. The study aimed to explore changes in the gene expression profiles and identify key genes involved in CLE, hoping to uncover its molecular mechanism and identify new targets for CLE. METHOD: We analyzed the microarray dataset (GSE109248) derived from the Gene Expression Omnibus (GEO) database, which was a transcriptome profiling of CLE cutaneous lesions. The differentially expressed genes (DEGs) were identified, and the functional annotation of DEGs was performed with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Protein-protein interaction (PPI) network was also constructed to identify hub genes involved in CLE. RESULT: A total of 755 up-regulated DEGs and 405 down-regulated DEGs were identified. GO enrichment analysis showed that defense response to virus, immune response, and type I interferon signaling pathway were the most significant enrichment items in DEGs. The KEGG pathway analysis identified 51 significant enrichment pathways, which mainly included systemic lupus erythematosus, osteoclast differentiation, cytokine-cytokine receptor interaction, and primary immunodeficiency. Based on the PPI network, the study identified the top 10 hub genes involved in CLE, which were CXCL10, CCR7, FPR3, PPARGC1A, MMP9, IRF7, IL2RG, SOCS1, ISG15, and GSTM3. By comparison between subtypes, the results showed that ACLE had the least DEGs, while CCLE showed the most gene and functional changes. CONCLUSION: The identified hub genes and functional pathways found in this study may expand our understanding on the underlying pathogenesis of CLE and provide new insights into potential biomarkers or targets for the diagnosis and treatment of CLE. Key Points • The bioinformatics analysis based on CLE patients and healthy controls was performed and 1160 DEGs were identified • The 1160 DEGs were mainly enriched in biological processes related to immune responses, including innate immune response, type I interferon signaling pathway, interferon-γ-mediated signaling pathway, positive regulation of T cell proliferation, regulation of immune response, antigen processing, and presentation via MHC class Ib and so on • KEGG pathway enrichment analysis indicated that DEGs were mainly enriched in several immune-related diseases and virus infection, including systemic lupus erythematosus, primary immunodeficiency, herpes simplex infection, measles, influenza A, and so on • The hub genes such as CXCL10, IRF7, MMP9, CCR7, and SOCS1 may become new markers or targets for the diagnosis and treatment of CLE.


Assuntos
Biologia Computacional , Lúpus Eritematoso Cutâneo , Perfilação da Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Humanos , Mapas de Interação de Proteínas , Transcriptoma
11.
Healthcare (Basel) ; 9(4)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33915709

RESUMO

OBJECTIVE: To study the changes in urine metabolism in female water polo players before and after high-intensity training by using ultra-high performance liquid chromatography-mass spectrometry, and to explore the biometabolic characteristics of urine after training and competition. METHODS: Twelve young female water polo players (except goalkeepers) from Shanxi Province were selected. A 4-week formal training was started after 1 week of acclimatization according to experimental requirements. Urine samples (5 mL) were collected before formal training, early morning after 4 weeks of training, and immediately after 4 weeks of training matches, and labeled as T1, T2, and T3, respectively. The samples were tested by LC-MS after pre-treatment. XCMS, SIMCA-P 14.1, and SPSS16.0 were used to process the data and identify differential metabolites. RESULTS: On comparing the immediate post-competition period with the pre-training period (T3 vs. T1), 24 differential metabolites involved in 16 metabolic pathways were identified, among which niacin and niacinamide metabolism and purine metabolism were potential post-competition urinary metabolic pathways in the untrained state of the athletes. On comparing the immediate post-competition period with the post-training period (T3 vs. T2), 10 metabolites involved in three metabolic pathways were identified, among which niacin and niacinamide metabolism was a potential target urinary metabolic pathway for the athletes after training. Niacinamide, 1-methylnicotinamide, 2-pyridone, L-Gln, AMP, and Hx were involved in two metabolic pathways before and after the training. CONCLUSION: Differential changes in urine after water polo games are due to changes in the metabolic pathways of niacin and niacinamide.

12.
J Biol Chem ; 284(41): 28306-28318, 2009 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-19643730

RESUMO

SLC26 proteins function as anion exchangers, channels, and sensors. Previous cellular studies have shown that Slc26a3 and Slc26a6 interact with the R-region of the cystic fibrosis transmembrane conductance regulator (CFTR), (R)CFTR, via the Slc26-STAS (sulfate transporter anti-sigma) domain, resulting in mutual transport activation. We recently showed that Slc26a9 has both nCl(-)-HCO(3)(-) exchanger and Cl(-) channel function. In this study, we show that the purified STAS domain of Slc26a9 (a9STAS) binds purified (R)CFTR. When Slc26a9 and (R)CFTR fragments are co-expressed in Xenopus oocytes, both Slc26a9-mediated nCl(-)-HCO(3)(-) exchange and Cl(-) currents are almost fully inhibited. Deletion of the Slc26a9 STAS domain (a9-DeltaSTAS) virtually eliminated the Cl(-) currents with only a modest affect on nCl(-)-HCO(3)(-) exchange activity. Co-expression of a9-DeltaSTAS and the (R)CFTR fragment did not alter the residual a9-DeltaSTAS function. Replacing the Slc26a9 STAS domain with the Slc26a6 STAS domain (a6-a9-a6) does not change Slc26a9 function and is no longer inhibited by (R)CFTR. These data indicate that the Slc26a9-STAS domain, like other Slc26-STAS domains, binds CFTR in the R-region. However, unlike previously reported data, this binding interaction inhibits Slc26a9 ion transport activity. These results imply that Slc26-STAS domains may all interact with (R)CFTR but that the physiological outcome is specific to differing Slc26 proteins, allowing for dynamic and acute fine tuning of ion transport for various epithelia.


Assuntos
Antiporters/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/química , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Animais , Antiporters/genética , Bicarbonatos/metabolismo , Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Células Epiteliais/metabolismo , Feminino , Humanos , Técnicas de Patch-Clamp , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transportadores de Sulfato , Xenopus laevis
13.
Int Immunopharmacol ; 84: 106470, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32304991

RESUMO

Activation of hepatic stellate cells (HSCs) is a pivotal event in liver fibrosis, characterized by enhanced retinoic acid signals. Although up-regulated retinoic acid signal responds further to maintain HSC activation, the underlying molecular mechanisms are largely unknown. In this study, we sought to investigate the role of lncRNA-H19 in regulation of retinoic acid signals, and to further examine the underlying mechanism in this molecular context. We found that lncRNA-H19 upregulation could enhance retinoic acid signals to induce HSC activation, whereas lncRNA-H19 knockdown completely disturbed retinoic acid signals. Moreover, the activation of retinoic acid signals impaired the lncRNA-H19 knockdown mediated HSC inactivation. Interestingly, we also found that enhanced retinoic acid signals by lncRNA-H19 was associated with a coordinate increase in retinol metabolism during HSC activation. Increased retinol metabolism contributed to obvious lipid droplet consumption. Importantly, we identified that alcohol dehydrogenase III (ADH3) was essential for lncRNA-H19 to enhance retinoic acid signals. The inhibition of ADH3 completely abrogated the lncRNA-H19 mediated retinoic acid signals and HSC activation. Of note, we identified dihydroartemisinin (DHA) as a natural inhibitor for lncRNA-H19. Treatment with DHA significantly decreased the expression of lncRNA-H19, reduced the expression of ADH3, blocked retinoic acid signals, and in turn, inhibited HSC activation. Overall, these results provided novel implications to reveal the molecular mechanism of increased retinoic acid signals during HSC activation, and identify lncRNA-H19/ADH3 pathway as a potential target for the treatment of liver fibrosis.


Assuntos
Aldeído Oxirredutases/metabolismo , Células Estreladas do Fígado/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Tretinoína/metabolismo , Animais , Artemisininas/farmacologia , Tetracloreto de Carbono/efeitos adversos , Linhagem Celular , Técnicas de Silenciamento de Genes , Metabolismo dos Lipídeos , Fígado/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , RNA Longo não Codificante/antagonistas & inibidores , Receptores do Ácido Retinoico/efeitos dos fármacos , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , Transdução de Sinais , Vitamina A/metabolismo
14.
Am J Physiol Renal Physiol ; 297(1): F36-45, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19420109

RESUMO

We previously found that the Ca(2+)-sensing receptor (CaR) interacts with and inactivates the inwardly rectifying K(+) channel Kir4.2 that is expressed in the kidney cortex and that has a COOH-terminal PDZ domain. To identify potential scaffolding proteins that could organize a macromolecular signaling complex involving the CaR and Kir4.2, we used yeast two-hybrid cloning with the COOH-terminal 125 amino acids (AA) of Kir4.2 as bait to screen a human kidney cDNA library. We identified two independent partial cDNAs corresponding to the COOH-terminal 900 AA of MUPP1, a protein containing 13 PDZ binding domains that is expressed in the kidney in tight junctions and lateral borders of epithelial cells. When expressed in human embryonic kidney (HEK)-293 cells, Kir4.2 coimmunoprecipitates reciprocally with MUPP1 but not with a Kir4.2 construct lacking the four COOH-terminal amino acids, Kir5.1, or the CaR. MUPP1 and Kir4.2 coimmunoprecipitate reciprocally from rat kidney cortex extracts. Coexpression of MUPP1 with Kir4.2 in HEK-293 cells leads to reduced cell surface expression of Kir4.2 as assessed by cell surface biotinylation. Coexpression of MUPP1 and Kir4.2 in Xenopus oocytes results in reduced whole cell currents compared with expression of Kir4.2 alone, whereas expression of Kir4.2DeltaPDZ results in minimal currents and is not affected by coexpression with MUPP1. Immunofluorescence studies of oocytes demonstrate that MUPP1 reduces Kir4.2 membrane localization. These results indicate that Kir4.2 interacts selectively with MUPP1 to affect its cell surface expression. Thus MUPP1 and Kir4.2 may participate in a protein complex in the nephron that could regulate transport of K(+) as well as other ions.


Assuntos
Proteínas de Transporte/metabolismo , Membrana Celular/metabolismo , Rim/citologia , Rim/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Feminino , Humanos , Proteínas de Membrana , Oócitos/citologia , Oócitos/metabolismo , Domínios PDZ/fisiologia , Técnicas de Patch-Clamp , Plasmídeos , Domínios e Motivos de Interação entre Proteínas/fisiologia , Ratos , Receptores de Detecção de Cálcio/metabolismo , Saccharomyces cerevisiae , Transfecção , Xenopus laevis
15.
Clin Res Hepatol Gastroenterol ; 42(3): 261-268, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29307515

RESUMO

BACKGROUND AND OBJECTIVE: The World Health Organization (WHO) has revised its grading system for pancreatic neuroendocrine tumors (PNETs) in 2010 into three main group, which has not been widely and comprehensively evaluated. We aimed to validate the clinical valve of this system associated with the clinical outcome and long-term survival when applied to PNETs, which were rare and heterogeneous. METHODS: We retrospectively collected and analyzed the data of 150 consecutive patients with PNETs who underwent a resection. RESULTS: Sixty-four males and 86 females with PNETs were enrolled in our study. The clinical stage from I to IV by European Neuroendocrine Tumor Society were respectively defined in 53, 60, 19 and 18 patients. Seventy-two patients were pathologically diagnosed as neuroendocrine tumor G1 (NET G1), 48 as neuroendocrine tumor G2 (NET G2) and 30 as neuroendocrine carcinoma G3 (NEC G3). Patients with a radical resection obtained a notably higher overall survival (OS) than that of patients who underwent a palliative surgery (P=0.001). The 5-year OS of patients with NET G1 was significantly higher than that of patients with NET G2 (P=0.015) and NEC G3 (P<0.001); the comparison of OS for patients with NET G2 and NEC G3 was also statistically significant (P=0.005). In both univariate and multivariate analysis, clinical staging by ENETS (stage I and II vs. stage III and IV), resection (radical vs. palliative) and WHO 2010 grading classification (NET G1 and G2 vs. NEC G3) were validated to be independent predictors for the survivals of PNETs. CONCLUSION: The newly-updated WHO 2010 grading classification was prognostic for the OS of PNETs and could be widely adopted in clinical practice.


Assuntos
Tumores Neuroendócrinos/mortalidade , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Tumores Neuroendócrinos/classificação , Tumores Neuroendócrinos/cirurgia , Neoplasias Pancreáticas/classificação , Neoplasias Pancreáticas/cirurgia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Organização Mundial da Saúde , Adulto Jovem
16.
Lancet Neurol ; 13(8): 795-806, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25008548

RESUMO

BACKGROUND: Antibodies have been implicated in the pathogenicity of multiple sclerosis by findings of immunoglobulins in patients' CSF and often IgG and complement in lesions, and by a 2012 report that nearly half of patients' serum samples contain IgG specific for a glial potassium-channel, KIR4.1. We aimed to establish the frequency of KIR4.1-binding IgG in serum and CSF of patients with multiple sclerosis, and whether KIR4.1 immunoreactivity is retained or lost in demyelinating lesions. METHODS: Using ELISA with a KIR4.1 peptide, we tested archival serum from 229 population-based and 57 clinic-based patients with multiple sclerosis, 99 healthy controls, and 109 disease controls, and CSF from 25 patients with multiple sclerosis and 22 disease controls. We tested all CSF and serum samples from 50 of the clinic-based patients with multiple sclerosis on cells expressing functional KIR4.1, using cell-based immunofluorescence and immunoprecipitation (solubilised recombinant human KIR4.1). We assessed KIR4.1 immunoreactivity in archival brain samples from 15 patients with histopathologically confirmed multiple sclerosis (22 plaques [eight early active, eight inactive, and six remyelinated], 13 periplaque regions and eight normal-appearing white-matter and grey-matter regions) and from three controls with non-neurological diseases. FINDINGS: Three of 286 serum samples from patients with multiple sclerosis and two of 208 serum samples from controls showed KIR4.1 reactivity on ELISA; none of the CSF samples from patients or controls showed KIR4.1 reactivity. IgG in none of the 50 serum samples from clinic-based patients immunoprecipitated KIR4.1, but a commercial KIR4.1-specific control IgG did. By immunofluorescence, one of 50 serum samples from patients with multiple sclerosis yielded faint plasmalemmal staining on both KIR4.1-expressing and non-expressing cells; 16 bound faintly to intracellular components. In all cases, IgG binding was quenched by absorption with liver powder or lysates from non-transfected cells. Binding by the KIR4.1-specific control IgG was quenched only by lysates containing KIR4.1. IgG in none of the 25 CSF samples from patients with multiple sclerosis bound to KIR4.1-transfected cells. Glial KIR4.1 immunoreactivity was increased relative to expression in healthy control brain in all active demyelinating lesions, remyelinated lesions, and periplaque white matter regions. INTERPRETATION: We did not detect KIR4.1-specific IgG in serum or CSF from patients with multiple sclerosis or KIR4.1 loss from glia in multiple sclerosis lesions. Serological testing for KIR4.1-specific IgG is unlikely to aid diagnosis of multiple sclerosis. The target antigen of multiple sclerosis remains elusive. FUNDING: The National Institutes of Health, the National Multiple Sclerosis Society, and the Mayo Clinic Robert and Arlene Kogod Center on Aging.


Assuntos
Autoantígenos/imunologia , Esclerose Múltipla/sangue , Esclerose Múltipla/líquido cefalorraquidiano , Canais de Potássio Corretores do Fluxo de Internalização , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoantígenos/sangue , Autoantígenos/líquido cefalorraquidiano , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Criança , Feminino , Humanos , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Imunoglobulina G/líquido cefalorraquidiano , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico , Vigilância da População , Canais de Potássio Corretores do Fluxo de Internalização/sangue , Canais de Potássio Corretores do Fluxo de Internalização/líquido cefalorraquidiano , Ligação Proteica/fisiologia , Adulto Jovem
17.
Mol Aspects Med ; 34(2-3): 159-82, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23506864

RESUMO

The SLC4 family consists of 10 genes (SLC4A1-5; SLC4A7-11). All encode integral membrane proteins with very similar hydropathy plots-consistent with 10-14 transmembrane segments. Nine SLC4 members encode proteins that transport HCO3(-) (or a related species, such as CO3(2-)) across the plasma membrane. Functionally, eight of these proteins fall into two major groups: three Cl-HCO3 exchangers (AE1-3) and five Na(+)-coupled HCO3(-) transporters (NBCe1, NBCe2, NBCn1, NBCn2, NDCBE). Two of the Na(+)-coupled transporters (NBCe1, NBCe2) are electrogenic; the other three Na(+)-coupled HCO3(-) transporters and all three AEs are electroneutral. In addition, two other SLC4 members (AE4, SLC4A9 and BTR1, SLC4A11) do not yet have a firmly established function. Most, though not all, SLC4 members are functionally inhibited by 4,4'-diisothiocyanatostilbene-2,2'-disulfonate (DIDS). SLC4 proteins play important roles many modes of acid-base homeostasis: the carriage of CO2 by erythrocytes, the transport of H(+) or HCO3(-) by several epithelia, as well as the regulation of cell volume and intracellular pH.


Assuntos
Bicarbonatos/metabolismo , Antiportadores de Cloreto-Bicarbonato/genética , Antiportadores de Cloreto-Bicarbonato/fisiologia , Modelos Moleculares , Família Multigênica/genética , Conformação Proteica , Simportadores de Sódio-Bicarbonato/genética , Simportadores de Sódio-Bicarbonato/fisiologia , Antiportadores de Cloreto-Bicarbonato/metabolismo , Eritrócitos/metabolismo , Componentes do Gene , Humanos , Simportadores de Sódio-Bicarbonato/metabolismo
18.
J Plant Res ; 120(2): 337-43, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17287892

RESUMO

The vascular tissue of roots performs essential roles in the physical support and transport of water, nutrients, and signaling molecules in higher plants. The molecular mechanisms underlying the function of root vascular tissue are poorly understood. In this study, we analyzed the expression pattern of AtGRP9, a salt stress-responsive gene encoding a glycine-rich protein, and its interacting partner, in Arabidopsis thaliana. Analysis of GUS or GFP expression under the control of the AtGRP9 promoter showed that AtGRP9 was expressed in the vascular tissue of the root; subcellular localization analysis further demonstrated that AtGRP9 proteins were localized in the cell wall and in the cytoplasm. Yeast two-hybrid analysis revealed that AtGRP9 interacted with AtCAD5, a major cinnamyl alcohol dehydrogenase (CAD) involved in lignin biosynthesis, for which tissue-specific distribution was comparable with that of AtGRP9. These results suggest that AtGRP9 may be involved in lignin synthesis in response to salt stress as a result of its interaction with AtCAD5 in A. thaliana.


Assuntos
Oxirredutases do Álcool/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Perfilação da Expressão Gênica , Raízes de Plantas/metabolismo , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Fluorescência Verde/metabolismo , Epiderme Vegetal/citologia , Ligação Proteica , Transporte Proteico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Plântula/citologia , Frações Subcelulares/metabolismo
19.
Plant Cell Rep ; 26(2): 237-45, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16972091

RESUMO

The halophyte Thellungiella halophila (salt cress) is an ideal model system for studying the molecular mechanisms of salinity tolerance in plants. Herein, we report the identification of a stress-responsive cyclophilin gene (ThCYP1) from T. halophila, using fission yeast as a functional system. The expression of ThCYP1 is highly inducible by salt, abscisic acid (ABA), H(2)O(2) and heat shock. Ectopic overexpression of the ThCYP1 gene enhance the salt tolerance capacity of fission yeast and tobacco (Nicotiana tabacum L.) cv. Bright Yellow 2 (BY-2) cells significantly. ThCYP1 is expressed constitutively in roots, stems, leaves and flowers, with higher expression occurring in the roots and flowers. The ThCYP1 proteins are distributed widely within the cell, but are enriched significantly in the nucleus. The present results suggest that ThCYP1 may participate in response to stresses in the salt cress, perhaps by regulating appropriate folding of certain stress-related proteins, or in the signal transduction processes.


Assuntos
Brassicaceae/genética , Ciclofilinas/genética , Nicotiana/genética , Schizosaccharomyces/genética , Cloreto de Sódio/farmacologia , Ácido Abscísico/farmacologia , Brassicaceae/fisiologia , Ciclofilinas/fisiologia , DNA Complementar , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Schizosaccharomyces/fisiologia , Nicotiana/citologia , Nicotiana/fisiologia , Transformação Genética
20.
Plant Cell Physiol ; 47(8): 1058-68, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16854938

RESUMO

Plant non-symbiotic hemoglobins (nsHbs) play important roles in a variety of cellular processes. Previous evidence from this laboratory indicates that the expression of a class 1 nsHb gene (GhHb1) from cotton is induced in cotton roots challenged with the Verticillium wilt fungus. The present study examined further the expression patterns of the GhHb1 gene in cotton plants and characterized its in vivo function through ectopic overexpression of the gene in Arabidopsis thaliana. Expression of GhHb1 in cotton plants was induced by exogenously applied salicylic acid, methyl jasmonic acid, ethylene, hydrogen peroxide (H(2)O(2)) and nitric oxide (NO). Ectopic overproduction of GhHb1 in Arabidopsis led to constitutive expression of the defense genes PR-1 and PDF1.2, and conferred enhanced disease resistance to Pseudomonas syringae and tolerance to V. dahliae. GhHb1-transgenic Arabidopsis seedlings were more tolerant to exogenous NO and contained lower levels of cellular NO than the wild-type control. Moreover, transgenic plants with relatively high levels of expression of the GhHb1 gene developed spontaneous hypersensitive lesions on the leaves in the absence of pathogen inoculation. Our results indicate that GhHb1 proteins play a role in the defense responses against pathogen invasions, possibly by modulating the NO level and the ratio of H(2)O(2)/NO in the defense process.


Assuntos
Arabidopsis/fisiologia , Hemoglobinas/fisiologia , Imunidade Inata/fisiologia , Óxido Nítrico/metabolismo , Transdução de Sinais/fisiologia , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Morte Celular/fisiologia , Defensinas/metabolismo , Gossypium/genética , Hemoglobinas/genética , Imunidade Inata/genética , Nitroprussiato/farmacologia , Plantas Geneticamente Modificadas , Pseudomonas syringae/fisiologia , Verticillium/patogenicidade , Verticillium/fisiologia , Virulência
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