Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 115
Filtrar
1.
PLoS Biol ; 19(7): e3001337, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34292944

RESUMO

Peripheral nerve injury-induced mechanical allodynia is often accompanied by abnormalities in the higher cortical regions, yet the mechanisms underlying such maladaptive cortical plasticity remain unclear. Here, we show that in male mice, structural and functional changes in the primary somatosensory cortex (S1) caused by peripheral nerve injury require neuron-microglial signaling within the local circuit. Following peripheral nerve injury, microglia in the S1 maintain ramified morphology and normal density but up-regulate the mRNA expression of brain-derived neurotrophic factor (BDNF). Using in vivo two-photon imaging and Cx3cr1CreER;Bdnfflox mice, we show that conditional knockout of BDNF from microglia prevents nerve injury-induced synaptic remodeling and pyramidal neuron hyperactivity in the S1, as well as pain hypersensitivity in mice. Importantly, S1-targeted removal of microglial BDNF largely recapitulates the beneficial effects of systemic BDNF depletion on cortical plasticity and allodynia. Together, these findings reveal a pivotal role of cerebral microglial BDNF in somatosensory cortical plasticity and pain hypersensitivity.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/fisiologia , Encéfalo/metabolismo , Hiperalgesia/fisiopatologia , Microglia/metabolismo , Plasticidade Neuronal/fisiologia , Traumatismos dos Nervos Periféricos/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Fator Neurotrófico Derivado do Encéfalo/genética , Camundongos , Camundongos Knockout , Traumatismos dos Nervos Periféricos/fisiopatologia
2.
BMC Infect Dis ; 24(1): 560, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840046

RESUMO

BACKGROUND: China experienced an overwhelming COVID-19 pandemic from middle December 2022 to middle January 2023 after lifting the zero-COVID-19 policy on December 7, 2022. However, the infection rate was less studied. We aimed to investigate the SARS-CoV-2 infection rate in children shortly after discontinuation of the zero-COVID-19 policy. METHODS: From February 20 to April 10, 2023, we included 393 children aged 8 months to less than 3 years who did not receive COVID-19 vaccination and 114 children aged 3 to 6 years who received inactivated COVID-19 vaccines based on the convenience sampling in this cross-sectional study. IgG and IgM antibodies against nucleocapsid (N) and subunit 1 of spike (S1) of SARS-CoV-2 (anti-N/S1) were measured with commercial kits (Shenzhen YHLO Biotech, China). RESULTS: Of the 393 unvaccinated children (1.5 ± 0.6 years; 52.2% boys), 369 (93.9%) were anti-N/S1 IgG positive. Of the 114 vaccinated children (5.3 ± 0.9 years; 48.2% boys), 112 (98.2%) were anti-N/S1 IgG positive. None of the unvaccinated or vaccinated children was anti-N/S1 IgM positive. The median IgG antibody titers in vaccinated children (344.91 AU/mL) were significantly higher than that in unvaccinated children (42.80 AU/mL) (P < 0.0001). The positive rates and titers of anti-N/S1 IgG had no significant difference between boys and girls respectively. CONCLUSION: Vast majority of children were infected with SARS-CoV-2 shortly after ending zero-COVID-19 policy in China. Whether these unvaccinated infected children should receive COVID-19 vaccine merits further investigation.


Assuntos
Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Imunoglobulina G , SARS-CoV-2 , Humanos , COVID-19/prevenção & controle , COVID-19/imunologia , COVID-19/epidemiologia , China/epidemiologia , Pré-Escolar , Masculino , Feminino , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Criança , Anticorpos Antivirais/sangue , SARS-CoV-2/imunologia , Lactente , Estudos Transversais , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Vacinação/estatística & dados numéricos , Glicoproteína da Espícula de Coronavírus/imunologia
3.
J Nanobiotechnology ; 22(1): 339, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890734

RESUMO

Diabetic kidney disease (DKD), a chronic kidney disease, is characterized by progressive fibrosis caused due to persistent hyperglycemia. The development of fibrosis in DKD determines the patient prognosis, but no particularly effective treatment. Here, small extracellular vesicles derived from mesenchymal stem cells (MSC-sEV) have been used to treat DKD fibrosis. Single-cell RNA sequencing was used to analyze 27,424 cells of the kidney, we have found that a novel fibrosis-associated TGF-ß1+Arg1+ macrophage subpopulation, which expanded and polarized in DKD and was noted to be profibrogenic. Additionally, Actin+Col4a5+ mesangial cells in DKD differentiated into myofibroblasts. Multilineage ligand-receptor and cell-communication analysis showed that fibrosis-associated macrophages activated the TGF-ß1/Smad2/3/YAP signal axis, which promotes mesangial fibrosis-like change and accelerates renal fibrosis niche. Subsequently, the transcriptome sequencing and LC-MS/MS analysis indicated that MSC-sEV intervention could restore the levels of the kinase ubiquitin system in DKD and attenuate renal interstitial fibrosis via delivering CK1δ/ß-TRCP to mediate YAP ubiquitination degradation in mesangial cells. Our findings demonstrate the unique cellular and molecular mechanisms of MSC-sEV in treating the DKD fibrosis niche at a single-cell level and provide a novel therapeutic strategy for renal fibrosis.


Assuntos
Nefropatias Diabéticas , Vesículas Extracelulares , Fibrose , Células-Tronco Mesenquimais , Análise de Célula Única , Transcriptoma , Vesículas Extracelulares/metabolismo , Células-Tronco Mesenquimais/metabolismo , Animais , Camundongos , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/terapia , Masculino , Camundongos Endogâmicos C57BL , Humanos , Macrófagos/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo , Células Mesangiais/metabolismo , Rim/patologia , Rim/metabolismo
4.
J Cell Biochem ; 124(8): 1145-1154, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37393598

RESUMO

As a master transcription factor, c-Myc plays an important role in promoting tumor immune escape. In addition, PPARγ (peroxisome proliferator-activated receptor γ) regulates cell metabolism, inflammation, and tumor progression, while the effect of PPARγ on c-Myc-mediated tumor immune escape is still unclear. Here we found that cells treated with PPARγ agonist pioglitazone (PIOG) reduced c-Myc protein expression in a PPARγ-dependent manner. qPCR analysis showed that PIOG had no significant effect on c-Myc gene levels. Further analysis showed that PIOG decreased c-Myc protein half-life. Moreover, PIOG increased the binding of c-Myc to PPARγ, and induced c-Myc ubiquitination and degradation. Importantly, c-Myc increased PD-L1 and CD47 immune checkpoint protein expression and promoted tumor immune escape, while PIOG inhibited this event. These findings suggest that PPARγ agonist inhibited c-Myc-mediated tumor immune escape by inducing its ubiquitination and degradation.


Assuntos
Neoplasias Colorretais , Pioglitazona , Tiazolidinedionas , Humanos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Regulação da Expressão Gênica , Pioglitazona/farmacologia , PPAR gama/agonistas , PPAR gama/metabolismo , Tiazolidinedionas/farmacologia , Evasão Tumoral , Proteínas Proto-Oncogênicas c-myc/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/metabolismo
5.
Cancer Cell Int ; 23(1): 151, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37525152

RESUMO

BACKGROUND: Exosome, a component of liquid biopsy, loaded protein, DNA, RNA and lipid gradually emerges as biomarker in tumors. However, exosomal circRNAs as biomarker and function mechanism in gastric cancer (GC) are not well understood. METHODS: Differentially expressed circRNAs in GC and healthy people were screened by database. The identification of hsa_circ_000200 was verified by RNase R and sequencing, and the expression of hsa_circ_000200 was evaluated using qRT-PCR. The biological function of hsa_circ_000200 in GC was verified in vitro. Western blot, RIP, RNA fluorescence in situ hybridization, and double luciferase assay were utilized to explore the potential mechanism of hsa_circ_000200. RESULTS: Hsa_circ_000200 up-regulated in GC tissue, serum and serum exosomes. Hsa_circ_000200 in serum exosomes showed better diagnostic ability than that of tissues and serum. Combined with clinicopathological parameters, its level was related to invasion depth, TNM staging, and distal metastasis. Functionally, knockdown of hsa_circ_000200 inhibited GC cells proliferation, migration and invasion in vitro, while its overexpression played the opposite role. Importantly, exosomes with up-regulated hsa_circ_000200 promoted the proliferation and migration of co-cultured GC cells. Mechanistically, hsa_circ_000200 acted as a "ceRNA" for miR-4659a/b-3p to increase HBEGF and TGF-ß/Smad expression, then promoted the development of GC. CONCLUSIONS: Our findings suggest that hsa_circ_000200 promotes the progression of GC through hsa_circ_000200/miR-4659a/b-3p/HBEGF axis and affecting the expression of TGF-ß/Smad. Serum exosomal hsa_circ_000200 may serve as a potential biomarker for GC.

6.
Proc Natl Acad Sci U S A ; 117(52): 32989-32995, 2020 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-33288692

RESUMO

Tibet's ancient topography and its role in climatic and biotic evolution remain speculative due to a paucity of quantitative surface-height measurements through time and space, and sparse fossil records. However, newly discovered fossils from a present elevation of ∼4,850 m in central Tibet improve substantially our knowledge of the ancient Tibetan environment. The 70 plant fossil taxa so far recovered include the first occurrences of several modern Asian lineages and represent a Middle Eocene (∼47 Mya) humid subtropical ecosystem. The fossils not only record the diverse composition of the ancient Tibetan biota, but also allow us to constrain the Middle Eocene land surface height in central Tibet to ∼1,500 ± 900 m, and quantify the prevailing thermal and hydrological regime. This "Shangri-La"-like ecosystem experienced monsoon seasonality with a mean annual temperature of ∼19 °C, and frosts were rare. It contained few Gondwanan taxa, yet was compositionally similar to contemporaneous floras in both North America and Europe. Our discovery quantifies a key part of Tibetan Paleogene topography and climate, and highlights the importance of Tibet in regard to the origin of modern Asian plant species and the evolution of global biodiversity.

7.
J Biol Chem ; 297(3): 100954, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34270958

RESUMO

Peroxisome proliferator-activated receptor δ (PPARδ) is a nuclear receptor transcription factor that plays an important role in the regulation of metabolism, inflammation, and cancer. In addition, the nutrient-sensing kinase 5'AMP-activated protein kinase (AMPK) is a critical regulator of cellular energy in coordination with PPARδ. However, the molecular mechanism of the AMPK/PPARδ pathway on cancer progression is still unclear. Here, we found that activated AMPK induced PPARδ-S50 phosphorylation in cancer cells, whereas the PPARδ/S50A (nonphosphorylation mimic) mutant reversed this event. Further analysis showed that the PPARδ/S50E (phosphorylation mimic) but not the PPARδ/S50A mutant increased PPARδ protein stability, which led to reduced p62/SQSTM1-mediated degradation of misfolded PPARδ. Furthermore, PPARδ-S50 phosphorylation decreased PPARδ transcription activity and alleviated PPARδ-mediated uptake of glucose and glutamine in cancer cells. Soft agar and xenograft tumor model analysis showed that the PPARδ/S50E mutant but not the PPARδ/S50A mutant inhibited colon cancer cell proliferation and tumor growth, which was associated with inhibition of Glut1 and SLC1A5 transporter protein expression. These findings reveal a new mechanism of AMPK-induced PPARδ-S50 phosphorylation, accumulation of misfolded PPARδ protein, and inhibition of PPARδ transcription activity contributing to the suppression of colon tumor formation.


Assuntos
Adenilato Quinase/metabolismo , Proliferação de Células , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Glucose/metabolismo , Glutamina/metabolismo , PPAR gama/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Xenoenxertos , Humanos , Camundongos Nus , Fosforilação
8.
J Transl Med ; 20(1): 483, 2022 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-36273156

RESUMO

Metabolic diseases, including obesity, diabetes, and nonalcoholic fatty liver disease (NAFLD), are rising in both incidence and prevalence and remain a major global health and socioeconomic burden in the twenty-first century. Despite an increasing understanding of these diseases, the lack of effective treatments remains an ongoing challenge. Mitochondria are key players in intracellular energy production, calcium homeostasis, signaling, and apoptosis. Emerging evidence shows that mitochondrial dysfunction participates in the pathogeneses of metabolic diseases. Exogenous supplementation with healthy mitochondria is emerging as a promising therapeutic approach to treating these diseases. This article reviews recent advances in the use of mitochondrial transplantation therapy (MRT) in such treatment.


Assuntos
Diabetes Mellitus , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Cálcio/metabolismo , Obesidade/metabolismo , Diabetes Mellitus/terapia , Mitocôndrias/metabolismo , Fígado/metabolismo
9.
J Cell Biochem ; 122(3-4): 394-402, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33164261

RESUMO

Epidermal growth factor receptor (EGFR) induces peroxisome-proliferator-activated receptor-δ (PPARδ)-Y108 phosphorylation, while it is unclear the effect of phosphorylation of PPARδ on cancer cell metabolism. Here we found that EGF treatment increased its protein stability by inhibiting its lysosomal dependent degradation, which was reduced by gefitinib (EGFR inhibitor) treatment. PPARδ-Y108 phosphorylation in response to EGF recruited HSP90 (heat shock protein 90) to PPARδ resulting in increased PPARδ stability. In addition, PPARδ-Y108 phosphorylation promoted cancer cell metabolism, proliferation, and chemoresistance. Therefore, this study revealed a novel molecular mechanism of EGFR/HSP90/PPARδ pathway-mediated cancer cell metabolism, proliferation, and chemoresistance, which provides a strategy for cancer treatment.


Assuntos
Receptores ErbB/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , PPAR delta/metabolismo , Western Blotting , Proliferação de Células/genética , Proliferação de Células/fisiologia , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Proteínas de Choque Térmico HSP90/genética , Células HT29 , Células HeLa , Humanos , Imunoprecipitação , PPAR delta/genética , Fosforilação/genética , Fosforilação/fisiologia , Estabilidade Proteica
10.
Cell Commun Signal ; 19(1): 91, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34493296

RESUMO

Autophagy is catabolic process by degradation of intracellular components in lysosome including proteins, lipids, and mitochondria in response to nutrient deficiency or stress such as hypoxia or chemotherapy. Increasing evidence suggests that autophagy could induce immune checkpoint proteins (PD-L1, MHC-I/II) degradation of cancer cells, which play an important role in regulating cancer cell immune escape. In addition to autophagic degradation of immune checkpoint proteins, autophagy induction in immune cells (macrophages, dendritic cells) manipulates antigen presentation and T cell activity. These reports suggest that autophagy could negatively or positively regulate cancer cell immune escape by immune checkpoint protein and antigens degradation, cytokines release, antigens generation. These controversial phenomenon of autophagy on cancer cell immune evasion may be derived from different experimental context or models. In addition, autophagy maybe exhibit a role in regulating host excessive immune response. So rational combination with autophagy could enhance the efficacy of cancer immunotherapy. In this review, the current progress of autophagy on cancer immune escape is discussed. Video Abstract.


Assuntos
Autofagia/genética , Imunoterapia , Neoplasias/imunologia , Evasão Tumoral/genética , Autofagia/imunologia , Antígeno B7-H1/genética , Humanos , Evasão da Resposta Imune/genética , Lisossomos/genética , Lisossomos/imunologia , Macrófagos/imunologia , Neoplasias/genética , Neoplasias/patologia , Linfócitos T/imunologia , Evasão Tumoral/imunologia
11.
Am J Bot ; 108(8): 1441-1463, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34431508

RESUMO

PREMISE: Microclimatic differences between the periphery and the interior of tree crowns result in a variety of adaptive leaf macromorphological and anatomical features. Our research was designed to reveal criteria for sun/shade leaf identification in two species of evergreen oaks, applicable to both modern and fossil leaves. We compared our results with those in other species similarly studied. METHODS: For both Quercus bambusifolia and Q. myrsinifolia (section Cyclobalanopsis), leaves from single mature trees with well-developed crowns were collected in the South China Botanical Garden, Guangzhou, China. We focus on leaf characters often preserved in fossil material. SVGm software was used for macromorphological measurement. Quantitative analyses were performed and box plots generated using R software with IDE Rstudio. Leaf cuticles were prepared using traditional botanical techniques. RESULTS: Principal characters for distinguishing shade and sun leaves in the studied oaks were identified as leaf lamina length to width ratio (L/W), and the degree of development of venation networks. For Q. myrsinifolia, shade and sun leaves differ in tooth morphology and the ratio of toothed lamina length to overall lamina length. The main epidermal characters are ordinary cell size and anticlinal wall outlines. For both species, plasticity within shade leaves exceeds that of sun leaves. CONCLUSIONS: Morphological responses to sun and shade in the examined oaks are similar to those in other plant genera, pointing to useful generalizations for recognizing common foliar polymorphisms that must be taken into account when determining the taxonomic position of both modern and fossil plants.


Assuntos
Quercus , China , Folhas de Planta , Plantas , Árvores
12.
Biochem Biophys Res Commun ; 532(4): 520-527, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-32896379

RESUMO

DPEP1 is highly expressed in the colorectal carcinoma tissues and colon cancer cells. However, the function and underlying mechanism of DPEP1 in the colon cancer cells are still poorly understood. Here, we found that transcription factor MYC could occupy on the DPEP1 promoter and activate its activities, and DPEP1 was up-regulated by MYC proteins in mRNA and protein levels in a dose-dependent manner in colon cancer cells. The expression levels of DPEP1 were positively correlated with that of MYC in colorectal tumor tissues. Moreover, Laser confocal images and Co-immunoprecipitation (Co-IP) revealed that DPEP1 and MYC proteins could bind to each other in the colon cancer cells. In turn, DPEP1 could enhance the stability of MYC proteins by extending the half-life of MYC proteins in colon cancer cells. Thus, DPEP1 and MYC proteins might form a positive feedback loop to maintain their high expression levels in colon cancer cells. In function, the MTT, EdU, Clone Formation assays and xenograft tumors assays demonstrated that DPEP1 could boost the proliferation of colon cancer cells through the DPEP1/MYC positive feedback loop in vitro and in vivo. Theoretically, DPEP1 may serve as a colon cancer biomarker and a novel target of colorectal carcinogenesis therapy.


Assuntos
Neoplasias do Colo/metabolismo , Dipeptidases/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Dipeptidases/biossíntese , Dipeptidases/metabolismo , Retroalimentação Fisiológica , Proteínas Ligadas por GPI/biossíntese , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Estabilidade Proteica , Ativação Transcricional
13.
J Plant Res ; 133(2): 157-173, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31915952

RESUMO

Although many fossil and molecular data suggest migrations from Malesia and Asia to Australia appear to dominate floristic exchange between Australian and Asian rainforests, evidence is emerging that demonstrate dispersal of plant groups from Australia to Asia. In this paper, a new species Agathis ledongensis sp. nov. is described on the basis of silicified wood from the late Oligocene-early Miocene of the Qiutangling Formation in Ledong, Hainan Island, South China. It is the first fossil record of Agathis in the Northern Hemisphere, and the only known fossil evidence of its dispersal outside of Gondwana. The close affinity of the fossil wood from Ledong with the genus Agathis was confirmed by comparing quantitative traits in 31 wood samples of 20 species representing all three extant genera of the Araucariaceae. The percentage of tracheids with uniseriate pitting on radial walls is shown as an additional diagnostic trait for separating Agathis and Wollemia from Araucaria. The wood of Agathis ledongensis provides evidence for the dispersal of this important plant group from Australia, or another Gondwanan terrane, to eastern Asia based on reliable fossil data. It records the occurrence of this genus in Hainan Island by the early Miocene, i.e. at the beginning of the formation of the island chains between Australia and the South-East Asia and thus the provision of a land migration route. As the land routes between these continents were restricted at that time, the migration of Agathis to Malesia and Asia was presumably facilitated by long-distance dispersal of its winged seeds by wind.


Assuntos
Araucariaceae , Fósseis , Madeira , Ásia , Austrália , China , Ásia Oriental , Ilhas , Filogenia
14.
J Plant Res ; 132(2): 223-236, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30840210

RESUMO

A new fossil leaf species, Liquidambar bella (Altingiaceae), is described from the lower part of the Eocene Huangniuling Formation, Maoming Basin, South China. Suprabasal venation in the fossil lobed Liquidambar leaves is reported for the first time. The new species provides additional palaeobotanical evidence on the morphological variability of this genus supporting the idea of combining the genera Liquidambar, Semiliquidambar and Altingia into the single genus Liquidambar as proposed based on molecular markers.


Assuntos
Fósseis , Liquidambar/classificação , China
15.
Am J Otolaryngol ; 40(2): 253-256, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30477911

RESUMO

BACKGROUND: Although cognitive behavioral therapy (CBT) has been known with a theoretical basis for tinnitus patients, there still were lack of clinical evidence. OBJECTIVE: To evaluate the clinical efficacy of cognitive behavioral therapy (CBT) for treatment of chronic subjective tinnitus. METHODS: One hundred patients with chronic subjective tinnitus patients were randomly divided into control (50 cases) and intervention (50 cases) groups, which received the masking therapy and sound treatment and masking therapy and sound treatment plus CBT. The treatment efficacy was evaluated. RESULTS: The total effective rate in intervention group was significantly higher than control group (P < 0.01). After treatment, compared with control group, in intervention group the psychotic somatization, interpersonal sensitivity, depression, anxiety, hostility, terror, and phobic anxiety scores in Symptom Checklist-90 and Tinnitus Handicap Inventory score were significantly decreased (P < 0.05), the serum cortisol level was significantly decreased (P < 0.05), and the serum interleukin-2 level was significantly increased (P < 0.05). CONCLUSION: Based on the elimination the mood disorders and reduce the stress, CBT can significantly relieve the symptoms of chronic subjective tinnitus.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Zumbido/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiedade , Biomarcadores/sangue , Doença Crônica , Depressão , Feminino , Hostilidade , Humanos , Hidrocortisona/sangue , Interleucina-2/sangue , Masculino , Pessoa de Meia-Idade , Zumbido/diagnóstico , Zumbido/psicologia , Resultado do Tratamento , Adulto Jovem
16.
J Cell Biochem ; 118(6): 1556-1562, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27918085

RESUMO

Abundant nutrient availability including glucose and amino acids plays an important role in maintaining cancer cell energetic and biosynthetic pathways. As a nuclear receptor, peroxisome-proliferator-activated receptor α (PPARα) regulates inflammation and cancer progression, however, it is still unclear the interaction of PPARα with the cancer cell glucose metabolism. Here we found that PPARα reduced Glut1 (Glucose transporter 1) protein and gene levels in HCT-116, SW480, HeLa, and MCF-7 cancer cell lines. In contrast, silenced PPARα reversed this event. Further analysis shows that PPARα directly targeted the consensus PPRE motif of Glut1 promoter region resulting in Glut1 transcription repression. PPARα-mediated Glut1 transcription repression led to decreased influx of glucose in cancer cells. These findings revealed a novel mechanism of PPARα-mediated cancer cell Glut1 transcription repression. J. Cell. Biochem. 118: 1556-1562, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Regulação para Baixo , Transportador de Glucose Tipo 1/genética , Neoplasias/metabolismo , PPAR alfa/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Células HCT116 , Células HeLa , Humanos , Células MCF-7 , Neoplasias/genética , Regiões Promotoras Genéticas
17.
Clin Chem Lab Med ; 55(8): 1160-1167, 2017 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-28076299

RESUMO

BACKGROUND: Association between pro-atrial natriuretic peptide (proANP) and hyperuricemia has not yet been investigated in population. This study aimed to examine the association in Chinese Han women. METHODS: We measured plasma proANP, serum uric acid, and other traditional biomarkers in 1360 women older than 30 years residing in the Gusu district of Suzhou City. Association between plasma proANP and hyperuricemia was analyzed in women aged ≥45 years and those aged <45 years, respectively. RESULTS: In women aged ≥45 years, the odds ratio (OR) [95% confidence interval (CI)] of hyperuricemia with high proANP (over the median) was 0.57 (0.34-0.97) compared to those with low proANP (p=0.040). After adjustment for age and other potential covariates, a high plasma proANP was associated with a decreased risk of hyperuricemia in women aged ≥45 years (OR 0.40; 95% CI, 0.19-0.84), when the highest and lowest categories were compared. In contrast, there was no association between plasma proANP and hyperuricemia in women aged <45 years. We did not observe a significant interaction between age and proANP (pinteraction=0.113). Sensitivity analyses further confirmed these age-specific findings. CONCLUSIONS: Plasma proANP was significantly and inversely associated with hyperuricemia in Chinese Han women aged ≥45 years. This study suggests that an increased plasma proANP should be a protective factor of hyperuricemia among middle-aged and old women.


Assuntos
Fator Natriurético Atrial/sangue , Etnicidade , Hiperuricemia/sangue , Precursores de Proteínas/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , China/etnologia , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Ácido Úrico/sangue
18.
Carcinogenesis ; 37(2): 215-222, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26718225

RESUMO

Dysregulated expression of epidermal growth factor receptor (EGFR) has been implicated in many cancer events, while peroxisome proliferator-activated receptor γ (PPARγ) negatively regulates cancer progression. The molecular mechanism of EGFR interaction with PPARγ is still unclear. Here, we found that nuclear EGFR induced phosphorylation of PPARγ at Tyr-74 leading to PPARγ ubiquitination and degradation by mouse double minute 2 (MDM2) ubiquitin ligase. PPARγ degradation by EGFR/MDM2 signaling resulted in accumulation of nuclear factor-kappaB (NF-κB)/p65 protein levels and increasing NF-κB activation. In contrast, PPARγ-Y74A mutant reversed this event. Moreover, PPARγ-Y74A mutant suppressed cell proliferation and increased chemotherapeutic agent-induced cancer cell sensitivity. Importantly, the clinical findings show that the nuclear phosphorylation of PPARγ-Y74 and EGFR expression in colonic cancer tissues was higher than that in control normal tissues. Thus, our study revealed a novel molecular mechanism that nuclear EGFR/NF-κB signaling promoted cell proliferation by destructing PPARγ function, which provides a novel strategy for cancer treatment.


Assuntos
Neoplasias do Colo/patologia , Receptores ErbB/metabolismo , NF-kappa B/metabolismo , PPAR gama/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Neoplasias do Colo/metabolismo , Ativação Enzimática/fisiologia , Humanos , Imuno-Histoquímica , Imunoprecipitação , Camundongos , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/fisiologia
19.
Tumour Biol ; 37(4): 4275-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26803518

RESUMO

The inhibitor of growth-4 (ING-4) belongs to the inhibitor of growth (ING) family that is a type II tumor suppressor gene including five members (ING1-5). As a tumor suppressor, ING4 inhibits tumor growth, invasion, and metastasis by multiple signaling pathways. In addition to that, ING4 can facilitate cancer cell sensitivity to chemotherapy and radiotherapy. Although ING4 loss is observed for many types of cancers, increasing evidences show that ING4 can be used for gene therapy. In this review, the recent progress of ING4 regulating tumorigenesis is discussed.


Assuntos
Proteínas de Ciclo Celular/genética , Terapia Genética , Proteínas de Homeodomínio/genética , Neoplasias/genética , Proteínas Supressoras de Tumor/genética , Apoptose/genética , Carcinogênese/genética , Proteínas de Ciclo Celular/uso terapêutico , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/uso terapêutico , Humanos , Terapia de Alvo Molecular , Neoplasias/terapia , Proteínas Supressoras de Tumor/uso terapêutico
20.
J Plant Res ; 129(1): 3-12, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26578191

RESUMO

The thelypteroid ferns are widely distributed across tropical regions around the world, but information about their fossil representatives is scarce. A new species, Cyclosorus scutum Naugolnykh, Wang, Han et Jin was discovered from the Eocene Changchang Formation of Hainan Island, South China, and is described on the basis of sterile and fertile leaves, sori, sporangia and spores preserved in situ. Discovery of this new species clearly shows that climatic conditions of that time in this area were humid, i.e. warm and wet.


Assuntos
Clima , Gleiquênias/anatomia & histologia , Gleiquênias/fisiologia , Fósseis/anatomia & histologia , Dispersão Vegetal , China , Mudança Climática , Gleiquênias/classificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA