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1.
An exopolysaccharide (EPS) was isolated and purified from an Antarctic psychrophilic bacterium B-3, identified as Psychrobacter sp., and the activation of RAW264.7 cells by B-3 EPS was investigated. The results show that B-3 EPS, over a certain concentration range, promoted cell viability, nitric oxide production, tumor necrosis factor (TNF)α secretion, and phagocytic ability. Furthermore, TAK-242, an inhibitor of the toll-like receptor 4 (TLR4) significantly reduced nitric oxide production by these cells after stimulation with B-3 EPS. Moreover, B-3 EPS induced p65 phosphorylation and IκBα degradation in these cells. In conclusion, B-3 EPS might have activated RAW264.7 cells by combining with TLR4 on cell surface and triggering activation of NF-κB signaling pathways, implying that this EPS could activate macrophages and regulate initial immune response. 相似文献
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A novel marine active polypeptide(PCF),isolated from the gonochoric Chinese scallop,Chlamys farreri,has potential antioxidant and anti-apoptotic activity against ultraviolet irradiation.We investigated whether UVB-induced HaCaT cell apoptosis occurs via the mitochondrial pathways Apaf-1/caspase-9 and Smac/XIAP/caspase-3.We then investigated the molecular mechanisms controlling the anti-apoptotic effect of PCF.Pre-treatment with PCF and caspase-9 inhibitor significantly inhibited UVB-induced apoptosis in HaC... 相似文献
3.
We extracted marine low-temperature lysozyme (MLTL), a novel lysozyme, from a marine microorganism through fermentation. Our
previous study suggested that a low molecular weight (16 kDa) may exert anti-tumor activity through antiangiogenesis. In this
study, we extracted a high weight (39 kDa) and investigated its antiangiogenic activity in vivo and in vitro. Using zebrafish embryos as an in vivo study model, we found that treatment with MLTL significantly inhibited the growth of subintestinal vessels (SIVs) in a dose-dependent
manner and that 400 μg/ml MLTL was sufficient to block the growth of SIVs. An in vitro study conducted using human umbilical vein endothelial cells (HUVECs) revealed that MLTL suppressed the proliferation, migration
and tube formation of HUVECs in a dose-dependent manner. Interestingly, assays by flow cytometry and DNA electrophoresis indicated
that MLTL was able to induce apoptosis of HUVECs. Moreover, further study demonstrated that the disruption of intracellular
Ca2+ homeostasis may play an important role in MLTL induced apoptosis of HUVECs. Taken together, the results of this study demonstrate
for the first time that MLTL inhibits angiogenesis through its pleiotropic effects on vascular endothelial cells and induces
apoptosis through regulation of cellular Ca2+ levels. The results of this study also revealed a possible mechanism underlying the antiangiogenic effect of MLTL and suggested
that MLTL may be a promising new antiangiogenic agent for use in cancer therapy. 相似文献
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《中国海洋大学学报(英文版)》2021,(5)
STAT3 plays a particularly important role in several cancer-related signal transduction pathways. Silencing STAT3 via RNA interference or small molecule inhibitors induces the apoptosis of tumor cells, thereby inhibiting the growth of the tumors. In this study, short-hairpin RNA sequences targeting the STAT3 genes were designed, synthesized, and then connected to pGPU6/GFP/Neo plasmids as the shRNA-expression vectors. The expression of STAT3-shRNA was analyzed by real-time PCR, western blotting, and cell apoptosis assay to study the growth and apoptosis of the cells. Then, the effect of STAT3 knockdown on the NCI-H1650 cells was studied in a tumor mouse model. The results revealed that, after an in vitro transfection, the proliferation of NCI-H1650 cells was inhibited, and the cells were induced to apoptosis. The mRNA and protein expression levels of STAT3 were downregulated in the STAT3-sh RNA group. In vivo, the tumor mass and volume in the STAT3-sh RNA group were significantly lower than in the other two groups. Both the in vivo and in vitro results demonstrated a long-period inhibiting effect on NSCLC, especially in vivo,when the tumor inhibition rate could reach 50% in the STAT3-shRNA group, which is an exciting outcome. Moreover, the study of the conjugation of STAT3-shRNA and chitosan-based vectors revealed that they could be combined steadily with good cytocompatibility and transfection efficiency. These results together provide convincing evidence for the application of STAT3-shRNA used in the treatment of non-small lung cancer, which could be a promoting prospect for the development of gene therapy. 相似文献
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In this study, we evaluated the anti-proliferative activity of phlorotannins derived from brown algae Laminaria japonica Aresch extracts on the human hepatocellular carcinoma cell (BEL-7402) and on murine leukemic cells (P388) by MTT assay. Cells
were incubated with 100 μg/mL of the phlorotannin extract (PE) for 48 h. The inhibitory rate of PE on BEL-7402 and P388 cells
was 30.20±1.16% and 43.44±1.86%, respectively, and the half-inhibitory concentration of PE (IC50) on P388 and BEL-7402 cells was 120 μg/mL and >200 μg/mL, respectively. Microscopic observation shows that the morphologic
features of tumor cells treated with PE and 5-fluorouracil are markedly different from the normal control group. The inhibitory
rate of fraction A2 isolated from PE by sephadex LH-20 for BEL-7402 and P388 cells at the sample concentration of 70.42 μg/mL was 61.96±7.02%
and 40.47±8.70%, respectively. The apoptosis peak for fraction A2 was the most profound of all fractions used in the flow cytometry assay. The results indicate that the anti-proliferative
of this algal extract is associated with the total phlorotannin content. 相似文献
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Insulin-like growth factors (IGFs) are key regulators of development and growth. Here, we characterized the igf2 gene from olive flounder (Paralichthys olivaceus) and determined its temporal and spatial expression. We set up an in-vitro protein expression system in eukaryotic human embryonic kidney (HEK293T) cells and explored its effects on cell proliferation. The flounder igf2 cDNA contained a 648-bp open reading frame (ORF) encoding a protein of 215 amino acids (aa), which spanned the complete signal peptide (47 aa), mature peptide (70 aa), and E domain (98 aa). In adult flounder, igf2 mRNA was detected in all selected tissues. In early development, igf2 mRNA was detected throughout development from unfertilized eggs to hatching-stage embryos. In-situ hybridization analysis indicated that igf2 mRNA was specially expressed in the brain region, floor plate, hypochord, otic vesicle, and pectoral fin during embryogenesis. Western blotting analysis indicated that the soluble recombinant flounder IGF2 protein was successfully produced through eukaryotic expression in HEK293T cells. In addition, the recombinant IGF2 protein significantly promoted the proliferation of human cervical carcinoma (HeLa) and HEK293T cells. These results provide new information about the structural and functional conservation, expression patterns, and biological activity of the igf2 in teleosts.
相似文献9.
The use of a microwave-assisted extraction(MAE) method for the extraction of phlorotannins from Saccharina japonica Aresch(S.japonica) has been evaluated with particular emphasis on the influential parameters,including the ethanol concentration,solid/liquid ratio,extraction time,extraction temperature,and microwave power.The MAE procedure was optimized using single-factor design and orthogonal array design(OAD).The content of total phlorotannins in S.japonica was determined using a Folin-Ciocalteu(FC) assay.A maximum total phlorotannin content of 0.644 mg of phloroglucinol equivalent per gram of dry weight plant(mg PGE/g DW) was obtained using the optimized model,which included an ethanol concentration of 55%,solid/liquid ratio of 1:8,extraction time of 25 min,irradiation power of 400 W,and temperature of 60°C.Under similar conditions,the application of a conventional extraction method led to a lower phlorotannin yield of 0.585 mg PGE/g WD.These results demonstrated that the MAE approach provided better results for the extraction of phlorotannins from S.japonica and was a promising technique for the extraction of phenolic compounds from S.japonica and other materials.In addition,screening tests for the inhibitory activity showed that the phlorotannin-containing extracts significantly inhibited the growth of human hepatocellular carcinoma cells(HepG2) by inducing their apoptosis.The morphological changes that occurred during cell apoptosis were characterized using Hoechst33258 staining. 相似文献
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Marine bacterial strain Bacillus sp. CS30 exhibited high anticancer activity against Huh7.5 human liver cancer. We purified the corresponding anticancer agent by sequential acidic precipitation, methanol extraction, Sephadex LH-20 chromatography, and reversed phase high-performance liquid chromatography (RP-HPLC), then analyzed it in mass spectrometry. Based on the results of purification and mass spectrometry, we deduced that the anticancer agent was the same component as our previously purified antifungal agent surfactin CS30-2. However, to the best of our knowledge, this is the first report on the surfactin possessing both antifungal and anticancer activities. Surfactin CS30-2 was demonstrated to exhibit high anticancer activity in a dose-dependent manner against Huh7.5 liver cancer cells. Further investigation showed that surfactin CS30-2 induced the increased generation of reactive oxygen species (ROS) and severe disruption of cell membrane, thus leading to cell death. However, unlike previously reported surfactins, surfactin CS30-2 caused cancer cell death via necrosis instead of apoptosis. 相似文献
13.
??GPS/DR?????????У?GPS???????????????????????????ж??????DR?????????е???????DR??????????????????????????????????????????????λ??????????????????????????????????????????У???DR???????????????????????????????????Ч????λ????? 相似文献
14.
Hemocyte counts and phenoloxidase(PO)activity were examined after hemolymph being incubated in dopamine(DA),noradrenaline(NE)and serotonin(5-HT).Results showed that all the three biogenic amines(BAs)had a significant impact on total hemocyte count(THC),differential hemocyte count(DHC),and intracelluar and extracelluar phenoloxidase(PO)activity.Among these Bas,DA had the strongest effect on the above parameters,whereas 5-HT had the least effect.Preincubation with D1 receptor antagonist SCH23390,D2 receptor antagonist Sulpiride and 1:1 admixture of the two could significantly inhibit the effect of DA on these parameters.SCH23390 showed a stronger inhibitory effect than Sulpiride,and the admixture exhibited the strongest effect.These results suggested that the change of hemocyte count and activation of prophenoloxidase(proPO)system in Litopenaeusvan-namei hemocyte can be regulated by BAs,and DA modulates the two parameters via its receptors. 相似文献
15.
Polypeptide from Chlamys farreri inhibits UVB-induced apoptosis of HaCaT cells via iNOS/NO and HSP90
Polypeptide from Chlamys farreri(PCF) is a novel marine bioactive product that was isolated from the gonochoric Chinese scallop Chlamys farreri,and was found to be an effective antioxidant in our recent studies.In this study,we investigated the effect of PCF on ultraviolet B(UVB)-induced apoptosis of HaCaT cells and the intracellular signaling pathways involved.Pretreatment with the inducible nitric oxide synthase(iNOS) inhibitor S-methylisothiourea sulfate inhibited UVB-induced apoptosis,indicating that iN... 相似文献
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1 INTRODUCTION The unicellular Dunaliella salina, is one of the well studied microalgae for mass culture and is of commercial importance as a source of natural beta-carotene (Avron and Ben-Amot, 1992). D. sa- lina has desirable properties of halotolerance… 相似文献
17.
《中国海洋大学学报(英文版)》2017,(5)
Lymphocystis disease virus(LCDV) infects target cells by attaching to a 27.8 k Da receptor(27.8R) protein in flounder Paralichthys olivaceus, and anti-27.8R monoclonal antibodies(MAbs) have been developed. However, the 27.8R existence in tissues of sea bass(Lateolabrax japonicus) and its role in LCDV infection have remained unclear. In this study, the results of western blotting demonstrated that the same 27.8R was shared by flounder and sea bass. LCDV-free sea bass individuals were intramuscularly injected with LCDV, and viral copies were detected in tissues from 3 h post infection and showed a time-dependent increase during 9 days infection. Distribution and synthesis of 27.8R in sea bass tissues were investigated by using anti-27.8R MAbs as probes. It was found that 27.8R was distributed in all the tested tissues. The levels of 27.8R protein were highest in gill and skin, then a bit lowly in stomach, head kidney and heart, followed by spleen, intestine, blood cells, gonad and liver, and least in kidney and brain in healthy sea bass. Upon LCDV infection, 27.8R synthesis was up-regulated in each tissue, and higher in the tissues with higher LCDV copies. The 27.8R and LCDV were detected in some peripheral blood leukocytes but not in red blood cells. These results suggested that 27.8R was widely distributed in sea bass tissues, and it served as a receptor and correlated with tissue tropism of LCDV infection. Furthermore, leukocytes had the potential of being a LCDV carrier and were responsible for a systemic infection of LCDV in sea bass. 相似文献
18.
MyoD,Myf5,and myogenin are myogenic regulatory factors that play important roles during myogenesis.It is thought that MyoD and Myf5 are required for myogenic determination,while myogenin is important for terminal differentiation and lineage maintenance.To better understand the function of myogenic regulatory factors in muscle development of flounder,an important economic fish in Asia,real-time quantitative RT-PCR was used to characterize the expression patterns of MyoD,Myf5, and myogenin at early stages of embryo development,and in different tissues of the adult flounder.The results show that,Myf5 is the first gene to be expressed during the early stages of flounder development, followed by MyoD and myogenin.The expressions of Myf5,MyoD,and myogenin at the early stages have a common characteristic:expression gradually increased to a peak level,and then gradually decreased to an extremely low level.In the adult flounder,the expression of the three genes in muscle is much higher than that in other tissues,indicating that they are important for muscle growth and maintenance of grown fish.During embryonic stages,the expression level of MyoD might serve an important role in the balance between muscle cell differentiation and proliferation.When the MyoD expression is over 30%of its highest level,the muscle cells enter the differentiation stage. 相似文献
19.
应用Real-time PCR技术,研究脂多糖(lipopolysaccharide,LPS)、苯酚、硫酸铜刺激红笛鲷(Lutjanussanguineus)后非特异性细胞毒性细胞受体(NCCRP-1)基因在不同组织里的表达差异。结果发现,LPS刺激红笛鲷24 h后NCCRP-1在红笛鲷头肾、脾脏、胸腺、肝脏、心脏、脑、肌肉和肠组织中均有表达,其中头肾表达量最高,脾脏次之,然后依次是肝脏、脑、肌肉、胸腺和肠,心脏表达量最少。LPS、苯酚和CuSO4刺激红笛鲷后,随着刺激时间的增长,NCCRP-1表达量在各组织达到峰值的时间不同。以头肾为模式组织,RT-PCR的结果显示,红笛鲷NCCRP-1在LPS、苯酚和CuSO4的刺激下的表达模式相似,随着时间的增加NCCRP-1表达量逐渐增加,分别在24、9、12 h处达到最高,达到对照组的52、30、24倍左右,之后表达量开始下降。免疫组织化学表明,NCCRP-1只在头肾、脾脏和胸腺的特定细胞中表达。 相似文献