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1.
J Cell Biochem ; 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31595560

RESUMO

Matrine, a natural product extracted from the root of Sophora flavescens Ait, was the main chemical ingredient of compounds of Kushen injection, which has been widely used for its remarkable anticancer effects for years. The underlying mechanisms for Matrine regulations of human breast cancer stem cells (BrCSCs) are barely known. LIN28, a well-characterized suppressor of Let-7 microRNA biogenesis, playing vital roles in regulations of stem cells' renewal and tumorigenesis. Here we show that the compounds of Kushen injection derived Matrine could suppress the BrCSCs differentiation and self-renewal through downregulating the expression of Lin28A, resulting in the inactivation of Wnt pathway through a Let-7b-dependent way. In opposite to Matrine, Cisplatin treatment increases the ability of tumorsphere formation and the expression of BrCSCs markers, which was partially blocked by either Let-7b overexpression or CCND1 inhibition. Furthermore, Matrine sensitized BrCSCs to cisplatin's suppression of cancer expansion in vitro and in vivo. Our study uncovers the role of the LIN28A/Let-7 in BrCSCs renewal, and more importantly, elucidated a novel mechanism by which Matrine induces breast cancer involution.

2.
Nanoscale ; 11(41): 19086-19104, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31538999

RESUMO

The solid electrolyte interface (SEI) is a passivation layer formed on the surface of lithium-ion battery (LIB) anode materials produced by electrolyte decomposition. The quality of the SEI plays a critical role in the cyclability, rate capacity, irreversible capacity loss and safety of lithium-ion batteries (LIBs). The stability of the SEI is especially important for Si anodes which experience tremendous volume changes during cycling. Therefore, in this review we discuss the effect of the SEI on Si anodes. Firstly, the mechanism of formation, composition, and component properties of solid electrolyte interfaces (SEIs) are introduced, and the SEI of native-oxide-terminated Si is emphasized. Then the growth model and mechanical failure of SEIs are analyzed in detail, and the challenges facing SEIs of Si anodes are proposed. Moreover, we highlight several modification methods for SEIs on Si anodes, including electrolyte additives, surface-functionalization of Si, coating artificial SEIs or protective layers, and the structural design of Si-based composites. We believe that designing a high-quality SEI is of great significance and is beneficial for the improved electrochemical performance of Si anodes.

3.
Life Sci ; 232: 116630, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31279783

RESUMO

AIMS: Lung adenocarcinoma consists of multiple therapeutic targets, however, patients will inevitably progress to later stage diagnosis with Tyrosine Kinase Inhibitor treatment resistance. We aim to investigate the roles of non-coding TUSC7 in ordering the cell division tendency, helping to sensitize the resistance in a miRNA incorporating way. MATERIALS AND METHODS: Online study of bioinformatics analysis, molecular experiments of luciferase test, immunofluorescence staining and qRT-PCR were applied to dig out the mechanistic regulations. KEY FINDINGS: TUSC-7 inhibited the renewal ability of adenocarcinoma stem cells, yielding to asymmetric cell splitting. Informatics analysis and the luciferase testing confirmed the 3'UTR binding site, and revealed the post-transcriptional regulation of NUMB referring to miR-146. TUSC-7 sponged miR-146 and abolished its degradation toward to NUMB, and this integrated cascade made several genes become tangled to full functionality. SIGNIFICANCE: TUSC-7 was proved to be one strong suppressive lnc-RNA in lung adenocarcinoma stem cells, functioning through inactivating NOTCH signaling, and the turbulence on division modes precisely pointed to the key mechanisms of stem cells' renewal. The decreasing of tumor suppressive miR-146 was necessary in TUSC-7 conducted renewal repression, despite it alone could also reduce the renewal efficiency, indicating that more complicated non-coding genes may be involved in its regulation.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Células-Tronco Neoplásicas/metabolismo , RNA Longo não Codificante/fisiologia , Regiões 3' não Traduzidas , Adenocarcinoma de Pulmão/genética , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Humanos , Neoplasias Pulmonares/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo
4.
Virol Sin ; 34(4): 397-411, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31069716

RESUMO

Enterovirus A71 (EV-A71) is one of the main causative agents of hand, foot and mouth disease (HFMD) and it also causes severe neurologic complications in infected children. The interactions between some viruses and the host mitochondria are crucial for virus replication and pathogenicity. In this study, it was observed that EV-A71 infection resulted in a perinuclear redistribution of the mitochondria. The mitochondria rearrangement was found to require the microtubule network, the dynein complex and a low cytosolic calcium concentration. Subsequently, the EV-A71 non-structural protein 2BC was identified as the viral protein capable of inducing mitochondria clustering. The protein was found localized on mitochondria and interacted with the mitochondrial Rho GTPase 1 (RHOT1) that is a key protein required for attachment between the mitochondria and the motor proteins, which are responsible for the control of mitochondria movement. Additionally, suppressing mitochondria clustering by treating cells with nocodazole, EHNA, thapsigargin or A23187 consistently inhibited EV-A71 replication, indicating that mitochondria recruitment played a crucial role in the EV-A71 life cycle. This study identified a novel function of the EV-A71 2BC protein and provided a potential model for the regulation of mitochondrial motility in EV-A71 infection.

5.
Cell ; 177(6): 1553-1565.e16, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31104841

RESUMO

Enterovirus B (EV-B), a major proportion of the genus Enterovirus in the family Picornaviridae, is the causative agent of severe human infectious diseases. Although cellular receptors for coxsackievirus B in EV-B have been identified, receptors mediating virus entry, especially the uncoating process of echovirus and other EV-B remain obscure. Here, we found that human neonatal Fc receptor (FcRn) is the uncoating receptor for major EV-B. FcRn binds to the virus particles in the "canyon" through its FCGRT subunit. By obtaining multiple cryo-electron microscopy structures at different stages of virus entry at atomic or near-atomic resolution, we deciphered the underlying mechanisms of enterovirus attachment and uncoating. These structures revealed that different from the attachment receptor CD55, binding of FcRn to the virions induces efficient release of "pocket factor" under acidic conditions and initiates the conformational changes in viral particle, providing a structural basis for understanding the mechanisms of enterovirus entry.

6.
Talanta ; 201: 490-495, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31122455

RESUMO

A highly selective and sensitive direct detection of potassium (K+) and lead (Pb2+) ions was developed by using the assembly and disassembly of a chiral cyanine dye/TBA complex. The dye DMSB (3-ethyl-2-[3-(3-ethyl-3H-benzoselenazol-2-ylidene)-2-methylprop-1-enyl] benzoselenazolium bromide) loses the ability of self-assembly, but it can be activated by thrombin-binding aptamer (TBA) G-quadruplex structure. And only the TBA G-quadruplex formed in the presence of K+, can strongly induce J-aggregate signals of DMSB. Because the Pb2+ ions can bind and stabilize the TBA G-quadruplex with much higher efficiency than K+, the J-aggregate signals of DMSB falls sharply when the Pb2+ is present. As a result, the assembly and disassembly of DMSB allows the selective detection of 10 µM K+ and 20 nM Pb2+ respectively, even the competitive sodium ion (Na+) was as high as 145 mM. The linear correlation existed between the J-aggregate intensity and the concentration of K+ and Pb2+ over the range of 0.5-5.0 mM and 200-2000 nM, respectively. Moreover, the concentration of K+ (∼3 mM) and Pb2+ (below 20 nM) in human blood serum samples were determined by the present method, which agreed well with inductively coupled plasma mass spectrometry (ICP-MS). This work not only opens a door for the further development of G-quadruplex-based aptasensor in complex real system, but also provides a simple and versatile sensing platform for ion detection in clinic.

7.
Physiol Plant ; 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30637759

RESUMO

Plant responses to drought and their subsequent rehydration can provide evidence for forest dynamics within the context of climate change. In this study, the seedlings of two native species (Vitex negundo var. heterophylla, Quercus acutissima) and two exotic species (Robinia pseudoacacia, Amorpha fruticosa) to China were selected in a greenhouse experiment. The gas exchange, stem hydraulic parameters, plant osmoprotectant contents and antioxidant activities of the seedlings that were subjected to sustained drought and rehydration (test group) as well as those of well-irrigated seedlings (control group) were measured. The two native species exhibited a greater degree of isohydry with drought because they limited the stomatal opening timely from the onset of the drought. However, the two exotic species showed a more 'water spender'-like strategy with R. pseudoacacia showing anisohydric responses and A. fruticosa showing isohydrodynamic responses to drought. Severe drought significantly decreased the leaf gas exchange rates and hydraulic properties, whereas the instantaneous water use efficiency and osmoprotectant contents increased markedly. Most of the physiological parameters recovered rapidly after mild drought rehydration, but the water potential and/or supply of nonstructural carbohydrates did not recover after severe drought rehydration. The results demonstrate that the xylem hydraulic conductivity and shoot water potential jointly play a crucial role in the drought recovery of woody plants. In brief, the native species may play a dominant role in the future in warm-temperate forests because they employ a better balance between carbon gain and water loss than the alien species under extreme drought conditions.

8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 26(6): 1746-1751, 2018 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-30501715

RESUMO

OBJECTIVE: To detect the expression of JAK2/STAT3 mRNA in peripheral blood T cells from the patients with chronic idiopathic thrombocytopenic purpura(CITP), and to explore the relationship between JAK2/STAT3 mRNA and CITP. METHODS: CITP group and healthy control group were set in this study, The JAK2/STAT3 mRNA expression level in peropheral blood T cells of 2 groups was detected with the RT-PCR and agarose gel electrophoresis. RESULTS: JAK2 mRNA expression level in CITP group was significantly higher than that in control group(P<0.01), the STAT3 mRNA expression level in CITP group was also higher than control group(P<0.01), The JAK2/STAT3 mRNA expression level of CITP patiants increased obviously compared with control group. CONCLUSION: The expression level of JAK2/STAT3 mRNA increases signficanlty in chronic ITP patients, which involves in pathogenesis of CITP.

9.
Ecotoxicol Environ Saf ; 166: 259-269, 2018 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-30273849

RESUMO

Scientists are increasingly aware that heavy metal contamination in soils, especially in farmland ecosystems, can negatively affect human health and alter the bacterial community that plays a critical role in plant growth and heavy metal accumulation. The goal of the present paper was to uncover how various heavy metals and non-metallic elements affect human health and bacterial diversity in cornfields and to explore the contribution of soil bacteria to heavy metal accumulation in crops. Soil samples were collected from five counties in Shandong Province, China, where abnormally high levels of heavy metals and metalloids were caused by mining and heavy industry. We calculated a hazard quotient (HQ) to evaluate the health risk these heavy metals cause and analyzed the soil bacterial community using 16S rRNA gene sequencing. The HQ results showed that As posed the greatest threat to human health followed by Pb although concentrations of all metals did not reach the health risk threshold. Meanwhile, principal component analysis (PCA) and redundancy analysis (RDA) revealed soil bacterial richness was significantly influenced by As, Ni, and Cr as well as pH and phosphorus, but not by the species diversity of aboveground weeds. The most abundant bacteria in our study region were heavy metal tolerant groups, specifically Actinobacteria and Proteobacteria. Moreover, correlation analysis suggested that Actinobacteria might reduce the phytoaccumulation of Cr, Cu, Zn, and Hg in corn, while Proteobacteria might weaken phytoaccumulation of Pb, Ni, As, and Cd. Our results verified that heavy metals play an important role in shaping the soil bacterial community. Using native bacteria in farmland provides a potential biological strategy for reducing the health risk posed by heavy metals related to food consumption.

10.
J Cell Mol Med ; 22(12): 6262-6274, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30324719

RESUMO

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype with a poor prognosis. The microRNA-200 (miR-200) family has been associated with breast cancer metastasis. However, the epigenetic mechanisms underlying miR-200b repression in TNBC are not fully elucidated. In this study, we found that MYC proto-oncogene, bHLH transcription factor (MYC) and DNA methyltransferase 3A (DNMT3A) were highly expressed in TNBC tissues compared with other breast cancer subtypes, while miR-200b expression was inhibited significantly. We demonstrated that MYC physically interacted with DNMT3A in MDA-MB-231 cells. Furthermore, we demonstrated that MYC recruited DNMT3A to the miR-200b promoter, resulting in proximal CpG island hypermethylation and subsequent miR-200b repression. MiR-200b directly inhibited DNMT3A expression and formed a feedback loop in TNBC cells. MiR-200b overexpression synergistically repressed target genes including zinc-finger E-box-binding homeobox factor 1, Sex determining region Y-box 2 (SOX2), and CD133, and inhibited the migration, invasion and mammosphere formation of TNBC cells. Our findings reveal that MYC can collaborate with DNMT3A on inducing promoter methylation and miR-200b silencing, and thereby promotes the epithelial to mesenchymal transition and mammosphere formation of TNBC cells.

11.
Biomed Pharmacother ; 107: 1434-1446, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30257360

RESUMO

Increasing evidence has highlighted the pivotal roles of deregulated long non-coding RNAs (lncRNAs) in tumourigenesis. However, the biological functions and mechanisms of lncRNAs in human lung adenocarcinoma (LUAD) remain elusive. Small nucleolar RNA host gene 6 (SNHG6), a novel lncRNA, is aberrantly expressed in various cancers. In this study, SNHG6 was upregulated in LUAD tissues, and its upregulation was positively associated with advanced TNM stage, large tumour size and poor overall survival (OS) in LUAD patients. Gain- and loss-of-function experiments confirmed that SNHG6 promoted cell cycle progression, cell proliferation, migration and invasion, and epithelial-mesenchymal transition (EMT) in vitro. Animal experiments demonstrated that SNHG6 knockdown remarkably inhibited xenograft formation in vivo. Moreover, mechanistic experiments identified that SNHG6 functions as a competing endogenous RNA (ceRNA) through competitively sponging miR-26a-5p to regulate E2F7 expression, cell motility and EMT in LUAD cells. In summary, our findings reveal that SNHG6 may act as an oncogenic lncRNA in LUAD carcinogenesis by regulating the miR-26a-5p/E2F7 axis.

12.
Chem Commun (Camb) ; 54(68): 9466-9469, 2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30084446

RESUMO

MCMB@Si@C microspheres, in which silicon nanoparticles were closely connected with mesocarbon microbeads (MCMBs) through strong chemical bonds, were synthesized as high-performance Li-ion battery anodes for the first time. Furthermore, the different surface functional groups, as interconnecting species, and their effects on the anode performance were characterized in detail.

13.
Cell Prolif ; 51(5): e12473, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30094882

RESUMO

OBJECTIVES: FBXW7 acts as a tumour suppressor by targeting at various oncoproteins for ubiquitin-mediated degradation. However, the clinical significance and the involving regulatory mechanisms of FBXW7 manipulation of NSCLC regeneration and therapy response are not clear. MATERIALS AND METHODS: Immunohistochemical staining and qRT-PCR were applied to detect FBXW7 and Snai1 expression in 100 samples of NSCLC and matched tumour-adjacent tissues. FBXW7 manipulation of cancer biological functions were studied by using MTT assay, immunoblotting, flow cytometry, transwells, wound healing assay, and sphere-formation assays. Immunofluorescence and co-immunoprecipitation were used to analyse the possible interaction between Snai1 and FBXW7. RESULTS: We detected the decreased FBXW7 expression in majority of the NSCLC tissues, and lower FBXW7 level was correlated with advanced TNM stage. Furthermore, those patients with decreased FBXW7 expression tend to have both poorer 5-year survival outcomes, and shorter disease-free survival, comparing to those with higher FBXW7 levels. Functionally, we found that FBXW7 enforcement suppressed NSCLC progression by inducing cell growth arrest, increasing chemo-sensitivity and inhibiting Epithelial-mesenchymal Transition (EMT) progress. Results further showed that FBXW7 could interact with Snai1 directly to degrade its expression through ubiquitylating alternation in NSCLC, which could be partially abrogated by restoring Snai1 expression. CONCLUSIONS: FBXW7 conduction of tumour suppression was partly through degrading Snai1 directly for ubiquitylating regulation in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Resistencia a Medicamentos Antineoplásicos/fisiologia , Transição Epitelial-Mesenquimal/fisiologia , Proteína 7 com Repetições F-Box-WD/metabolismo , Neoplasias Pulmonares/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Ubiquitina/metabolismo , Células A549 , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Intervalo Livre de Doença , Feminino , Células HEK293 , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Cicatrização/fisiologia
14.
Int J Oncol ; 53(4): 1601-1612, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30066905

RESUMO

Tamoxifen (TAM) resistance is a substantial challenge in the treatment of estrogen receptor (ER)-positive breast cancer. Previous studies have revealed an important role of microRNA (miRNA/miR)-26a in TAM resistance in breast cancer. However, the mechanism underlying the regulatory effects of miR-26a on TAM resistance remains to be elucidated. The expression levels of miR-26a in ER-positive breast cancer were detected by reverse transcription-quantitative polymerase chain reaction. E2F transcription factor 7 (E2F7) and MYC proto-oncogene, bHLH transcription factor (MYC) levels were detected by western blotting. The present study demonstrated that miR-26a expression was reduced in ER-positive breast cancer compared with in normal breast tissues, whereas E2F7 expression was significantly elevated. Furthermore, an inverse correlation between miR-26a and E2F7 expression was detected in ER-positive breast cancer. The results indicated that miR-26a directly inhibited E2F7 expression through translational inhibition and indirectly inhibited MYC expression partly via E2F7 repression. E2F7, in turn, decreased miR-26a expression via MYC-induced transcriptional inhibition of miRNAs. Furthermore, transfection with miR-26a mimics increased the expression of its host genes (CTD small phosphatase like and CTD small phosphatase 2), whereas ectopic E2F7 expression abrogated the effects of miR-26a. These findings indicated that miR-26a and E2F7 may form a double-negative feedback loop, resulting in downregulation of miR-26a and upregulation of E2F7 in ER-positive breast cancer. Both miR-26a knockdown and E2F7 overexpression conferred resistance to TAM in MCF-7 cells. Conversely, miR-26a overexpression and E2F7 silencing resensitized MCF-7 resistant cells to TAM. These findings revealed that a feedback loop between miR-26a and E2F7 may promote TAM resistance in ER-positive breast cancer.

15.
Ecol Evol ; 8(13): 6615-6624, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30038761

RESUMO

While many introduced invasive species can increase genetic diversity through multiple introductions and/or hybridization to colonize successfully in new environments, others with low genetic diversity have to persist by alternative mechanisms such as epigenetic variation. Given that Phragmites australis is a cosmopolitan reed growing in a wide range of habitats and its invasion history, especially in North America, has been relatively well studied, it provides an ideal system for studying the role and relationship of genetic and epigenetic variation in biological invasions. We used amplified fragment length polymorphism (AFLP) and methylation-sensitive (MS) AFLP methods to evaluate genetic and epigenetic diversity and structure in groups of the common reed across its range in the world. Evidence from analysis of molecular variance (AMOVA) based on AFLP and MS-AFLP data supported the previous conclusion that the invasive introduced populations of P. australis in North America were from European and Mediterranean regions. In the Gulf Coast region, the introduced group harbored a high level of genetic variation relative to originating group from its native location, and it showed epigenetic diversity equal to that of the native group, if not higher, while the introduced group held lower genetic diversity than the native. In the Great Lakes region, the native group displayed very low genetic and epigenetic variation, and the introduced one showed slightly lower genetic and epigenetic diversity than the original one. Unexpectedly, AMOVA and principal component analysis did not demonstrate any epigenetic convergence between native and introduced groups before genetic convergence. Our results suggested that intertwined changes in genetic and epigenetic variation were involved in the invasion success in North America. Although our study did not provide strong evidence proving the importance of epigenetic variation prior to genetic, it implied the similar role of stable epigenetic diversity to genetic diversity in the adaptation of P. australis to local environment.

16.
Int J Biol Sci ; 14(8): 901-906, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29989071

RESUMO

Alpha-helical transmembrane protein (αTMP) is one of the two major categories of transmembrane protein (TMP). They are abundant existing in eukaryotic cells and involved in many biological processes. The special physicochemical properties, the structures of αTMP are hard to be experimentally solved, but αTMP's sequential segments are important to determine their conformations, so that TM-specific alignment is necessary to benefit their structure prediction. We used segment information extracted from topology structure and evolutionary information as features to implement a αTMP Segment Alignment method (TMSA). The method was trained using one non-redundant dataset and tested using another non-redundant dataset. Comparing the results to a general alignment method HHalign, TMSA achieved higher alignment accuracy, and easier to recognize the fold of αTMPs.

17.
Sci Immunol ; 3(24)2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29907691

RESUMO

Heterozygosity for human signal transducer and activator of transcription 3 (STAT3) dominant-negative (DN) mutations underlies an autosomal dominant form of hyper-immunoglobulin E syndrome (HIES). We describe patients with an autosomal recessive form of HIES due to loss-of-function mutations of a previously uncharacterized gene, ZNF341 ZNF341 is a transcription factor that resides in the nucleus, where it binds a specific DNA motif present in various genes, including the STAT3 promoter. The patients' cells have low basal levels of STAT3 mRNA and protein. The autoinduction of STAT3 production, activation, and function by STAT3-activating cytokines is strongly impaired. Like patients with STAT3 DN mutations, ZNF341-deficient patients lack T helper 17 (TH17) cells, have an excess of TH2 cells, and have low memory B cells due to the tight dependence of STAT3 activity on ZNF341 in lymphocytes. Their milder extra-hematopoietic manifestations and stronger inflammatory responses reflect the lower ZNF341 dependence of STAT3 activity in other cell types. Human ZNF341 is essential for the STAT3 transcription-dependent autoinduction and sustained activity of STAT3.

18.
Cell Cycle ; 17(12): 1445-1456, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29954239

RESUMO

MiR-146a could stimulate tumor growth or block tumor proliferation in systemic malignancies, referring to the specific downstream targeted gene. However, its roles in breast cancer stem-like cells (BrCSCs) are barely known. To dig out its mechanistic functions, we explored the indicative roles of miR-146 in preclinical study, regardless of the hormone receptor status, and the positive correlation between miR-146 and better prognosis was proved, as its correlation to Let-7c was. To uncover the implicated mechanisms, we first identified the suppressive role of miR-146a in stem cells' renewal, which was achieved by promoting the asymmetric division of BrCSCs. Let-7c was previously revealed with its suppressive functions in stem-like cells expansion, and miR-146 was predicated and successfully proved to bind to and degrade the 3'UTR of LIN28, a maturation blocker of Let-7 family. Results further showed that miR-146a increased the Let-7c level through degrading LIN28, and LIN28 inhibition is required for miR-146a induction of asymmetric stem cells' division. Moreover, Let-7 controlled Wnt signaling pathway activity could be strengthened due to the miR146 inhibition of H19, later of which was often activated in stem cells group with functional existence of Wnt signaling. H19 itself in turn formed the positive feedback regulation with Let-7. Our results suggested the miR-146a/LIN28/Wnt signaling circle in restraining the symmetric cells division, which was specifically referred to the controlling of the small circle of Let-7c and H19, and together, this dual axis could help to prohibit the stem cells expansion.

19.
Int J Biol Sci ; 14(5): 497-507, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29805301

RESUMO

Background: It has been reported that ultrasound enhances peripheral nerve regeneration, but the mechanism remains elusive. Low-intensity pulsed ultrasound (LIPUS) has been reported to enhance proliferation and alter protein production in various types of cells. In this study, we detected the effects of LIPUS on Schwann cells. Material and methods: Schwann cells were separated from new natal Sprague-Dawley rat sciatic nerves and were cultured and purified. The Schwann cells were treated by LIPUS for 10 minutes every day, with an intensity of 27.37 mW/cm2. After treatment for 5 days, MTT, EdU staining, and flow cytometry were performed to examine cell viability and proliferation. Neurotrophic factors, including FGF, NGF, BDNF, and GDNF, were measured by western blot and real-time PCR. GSK-3ß, p-GSK-3ß, ß-catenin and Cyclin D1 protein levels were detected using a western blot analysis. The expression of Cyclin D1 was also detected by immunofluorescence. Results: MTT and EdU staining showed that LIPUS increased the Schwann cells viability and proliferation. Compared to the control group, LIPUS increased the expression of growth factors and neurotrophic factors, including FGF, NGF, BDNF, GDNF, and Cyclin D1. Meanwhile, GSK-3ß activity was inhibited in the LIPUS group as demonstrated by the increased level of p-GSK-3ß and the ratio of the p-GSK-3ß/GSK-3ß level. The mRNA and protein expressions of ß-catenin were increased in the LIPUS group. However, SB216763, a GSK-3ß inhibitor, reversed the effects of LIPUS on Schwann cells. Conclusion: LIPUS promotes Schwann cell viability and proliferation by increasing Cyclin D1 expression via enhancing the GSK-3ß/ß-catenin signaling pathway.

20.
J Asian Nat Prod Res ; 20(6): 531-537, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29614875

RESUMO

Phytochemical investigation on the rhizomes of Atractylodes lancea led to the isolation of two new thiophene polyacetylene glycosides (1 and 2) and six known compounds (3-8). Their structures were elucidated based on the extensive spectroscopic data (UV, IR, 1D and 2D NMR, and HRESIMS). The absolute configurations of new compounds were established by calculated and experimental circular dichroism. All the compounds were assessed on the lipopolysaccharide-induced NO production in BV2 cells and compounds 3, 7, and 8 showed moderate inhibitory activities.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Atractylodes/química , Glicosídeos , Anti-Inflamatórios/química , Glicosídeos/química , Glicosídeos/isolamento & purificação , Estrutura Molecular , Poli-Inos/química , Poli-Inos/isolamento & purificação , Tiofenos/química , Tiofenos/isolamento & purificação
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