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Pingting Zhou Yanyan Li Bo Li Meichao Zhang Ci Xu Furao Liu 《Cell cycle (Georgetown, Tex.)》2018,17(8):997-1006
Osteosarcoma (OS) is the most prevalent bone malignancy in childhood and adolescence, with highly aggressive and early systemic metastases. Here, we reported that celecoxib, a selective COX-2 inhibitor in the NSAID class, exhibits strong antitumor activity in dose dependent manner in two OS cell lines-143B and U2OS. We showed that celecoxib inhibits OS cell growth, causes G0/G1-phase arrest, modulates apoptosis and autophagy and reduces migration in OS cells. In addition, the results of fluorescent mitochondrial probe JC-1 test indicated that the mitochondrial pathway mediates celecoxib-induced apoptosis. Significantly, the autophagy inhibitor CQ combined with celecoxib causes greater cell proliferation inhibition and apoptosis. Pharmacologic inhibition of autophagy with another potent autophagy inhibitor SAR405 also enhances celecoxib-mediated suppression of cell viability. These results were confirmed with shRNAs targeting the autophagy-related gene Atg5. In OS tumor xenografts in vivo, celecoxib also presents antitumor activity. Taken together, our results shed light on the function and mechanism of antitumor action of celecoxib for treatment of OS patients. 相似文献
43.
The α1‐adrenergic receptor is involved in hepcidin upregulation induced by adrenaline and norepinephrine via the STAT3 pathway 下载免费PDF全文
44.
Tianqi Liu Tianshu Yang Tingru Pan Ci Liu Shu Li 《Biological trace element research》2018,183(1):102-113
The aim of the present study was to clarify the effect of low selenium (Se)/high fat on the mRNA expression of selenoproteins, heat shock proteins (HSPs) and cytokines in pig peripheral blood lymphocytes. Forty crossbred boar piglets with healthy lean body weights of 10 kg were randomly divided into four treatment groups (group C, group L-Se, group H-fat, and group L-Se-H-fat) (n = 10/group) and fed with the corresponding diet for 16 weeks. The pig peripheral blood lymphocytes were extracted, and the mRNA expression of selenoproteins, HSPs, and cytokines was measured. Most mRNA levels for selenoproteins decreased in group L-Se, group H-fat, and group L-Se-H-fat, except Gpx1, Gpx2, Selt, and Selm, which were elevated in group H-fat. At the same time, low-Se/high-fat diet increased the expression of HSPs (HSP40, HSP60, HSP70, and HSP90) and inflammatory cytokines (IL-1α, IL-1β, IL-6, IL-8, IL-9, iNOS, COX-2, NF-κB, and TNF-α) in group L-Se, group H-fat, and group L-Se-H-fat, and genes in group L-Se-H-fat showed greater increases. Also, low-Se/high-fat diet inhibits the expression of TGF-β1 and IFN-γ. In summary, a low-Se/high-fat diet can cause relevant selenoprotein expression changes and promote the expression of pro-inflammatory factors and HSPs, and low Se enhances the expression of HSPs and inflammation factors induced by high fat. This information is helpful for understanding the effects of low-Se and high-fat diet on pig peripheral blood lymphocytes. 相似文献
45.
Qian Wang Ci Xu Qiang Fan Haihua Yuan Xin Zhang Biying Chen Renjie Cai Yanjie Zhang Moubin Lin Ming Xu 《Cell death & disease》2021,12(11)
MAPK/p38 is an important mammalian signaling cascade that responds to a variety of intracellular or extracellular stimuli, such as reactive oxygen species (ROS), and participates in numerous physiological and pathological processes. However, the biological function of p38 in different tumors, and even at different stages of the same tumor, remains elusive. To further understand the regulatory mechanism of p38 and oxidative stress in the occurrence and development of gastric cancer, we report SUMOylation as a novel post-translational modification occurring on lysine 152 of MAPK14/p38α through immunoprecipitation and series of pull-down assays in vitro and in vivo. Importantly, we determine that p38α-SUMOylation functions as an authentic sensor and accelerator of reactive oxygen species generation via interaction with and activation of MK2 in the nucleus, and the ROS accumulation, in turn, promotes the SUMOylation of p38α by stabilizing the PIASxα protein. This precise regulatory mechanism is exploited by gastric cancer cells to create an internal environment for survival and, ultimately, metastasis. This study reveals novel insights into p38α-SUMOylation and its association with the intracellular oxidative stress response, which is closely related to the processes of gastric cancer. Furthermore, the PIASxα/p38α-SUMOylation/MK2 cis-axis may serve as a desirable therapeutic target in gastric cancer as targeting PIASxα, MK2, or a specific peptide region of p38α may reconcile the aberrant oxidative stress response in gastric cancer cells.Subject terms: Gastric cancer, Sumoylation 相似文献
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为评估西双版纳国家级自然保护区对樟科这一重要植物类群进化潜力的保护情况, 揭示将物种进化历史纳入生物多样性保护评估的重要性, 本研究通过对西双版纳地区长期的野外调查并查阅标本记录与文献资料, 整理出该地区樟科13属121种物种的具体分布信息, 以植物条形码ITS序列作为分子标记构建了反映整个西双版纳地区樟科植物系统发育关系的系统发育树。我们以此为基础, 从物种层面分析了各物种的进化特异性(evolutionary distinctiveness, ED), 从区域层面分析了自然保护区内、外以及32个行政乡镇的系统发育多样性(phylogenetic diversity, PD), 并结合物种丰富度(species richness, SR)与物种濒危等级, 综合探讨了西双版纳国家级自然保护区对樟科植物进化历史的保护情况。研究发现, 西双版纳国家级自然保护区仅拥有整个西双版纳地区54.5%的樟科物种数, 却保护了该地区樟科植物约88.8%的进化历史, 没有被列入保护范围但却拥有高系统发育多样性的区域有打洛镇、易武乡等。就物种而言, 进化特异性相对较高的19个物种中, 有5种(26.3%)在自然保护区内没有分布; 濒危等级高的54个物种中, 有20种(37.0%)在自然保护区没有分布, 同时拥有高进化特异性和濒危等级的物种仅有1种不在保护区内分布。结果表明, 虽然西双版纳国家级自然保护区对樟科这一植物类群的系统发育多样性以及高保护价值物种的保护较好, 但仍有部分重要樟科植物的进化历史没有涵盖在现有自然保护区范围内; 按照传统方法设定的自然保护区虽能在一定程度上保护樟科物种的进化历史, 但仍然存在与标准化系统发育多样性保护策略相矛盾的地方。因此, 今后在建立自然保护区时, 应将系统发育多样性考虑在内, 以保护生物多样性应对环境变化的潜力。 相似文献
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Qing Li Chenye Shen Zhaolin Liu Yuanyuan Ma Jinghui Wang Hongtian Dong Xiaoshuang Zhang Zishan Wang Mei Yu Lei Ci Ruilin Sun Ruling Shen Jian Fei Fang Huang 《Cell proliferation》2021,54(8)
ObjectivesParkinson''s disease (PD) is a common neurodegenerative disorder characterized by the progressive and selective degeneration of dopaminergic neurons. Microglial activation and neuroinflammation are associated with the pathogenesis of PD. However, the relationship between microglial activation and PD pathology remains to be explored.Materials and MethodsAn acute regimen of MPTP was administered to adult C57BL/6J mice with normal, much reduced or repopulated microglial population. Damages of the dopaminergic system were comprehensively assessed. Inflammation‐related factors were assessed by quantitative PCR and Multiplex immunoassay. Behavioural tests were carried out to evaluate the motor deficits in MPTP‐challenged mice.ResultsThe receptor for colony‐stimulating factor 1 inhibitor PLX3397 could effectively deplete microglia in the nigrostriatal pathway of mice via feeding a PLX3397‐formulated diet for 21 days. Microglial depletion downregulated both pro‐inflammatory and anti‐inflammatory molecule expression at baseline and after MPTP administration. At 1d post‐MPTP injection, dopaminergic neurons showed a significant reduction in PLX3397‐fed mice, but not in control diet (CD)‐fed mice. However, partial microglial depletion in mice exerted little effect on MPTP‐induced dopaminergic injuries compared with CD mice at later time points. Interestingly, microglial repopulation brought about apparent resistance to MPTP intoxication.ConclusionsMicroglia can inhibit PD development at a very early stage; partial microglial depletion has little effect in terms of the whole process of the disease; and microglial replenishment elicits neuroprotection in PD mice. 相似文献
49.
Effect of high nitrate concentration on PHB storage in sequencing batch reactor under anoxic conditions 总被引:1,自引:0,他引:1
The study investigated effect of high influent nitrate concentration on poly-beta-hydroxybutyrate, (PHB), storage in a sequencing batch reactor, (SBR), under anoxic conditions. Acetate was fed as pulse during anoxic phase, sustained with external nitrate feeding. SBR operation involved three runs at steady state with COD/N ratios of 3.84, 2.93 and 1.54 gCOD/gN, where external nitrate concentrations gradually increased from 50 mg N/l to 114 mg N/l and 226 mg N/l, in 1st, 2nd and 3rd runs, respectively. In 1st run, acetate was fully converted into PHB with the storage yield value of 0.57-0.59 gCOD/gCOD, calculated both in terms of PHB formation and NO(X) utilization, confirming storage was the sole substrate utilization mechanism. In the following runs, PHB formation was reduced and the storage yield based on PHB dropped down to 0.40 and 0.33 gCOD/gCOD with increasing influent nitrate concentrations, indicating that higher portions of acetate were diverted to simultaneous direct growth. The observations suggested that nitrite accumulation detected at low COD/N ratios was responsible for inhibition of PHB storage. 相似文献
50.
Ci Su-Qin Chen Shan Dong-Bo Liu Hong-Mei Xia 《World journal of microbiology & biotechnology》2006,22(7):729-735
Summary
Penicillium sp. DS9713a-01 was obtained by ultraviolet (u.v.) light mutagenesis from the Penicillium sp. DS9713a which can degrade poly (3-hydroxybutyrate) (PHB). The enzymatic activity of DS9713a-01 was 97% higher than that
of the wild-type strain. The DS9713a-01 mutant could completely degrade PHB films in 5 days; however, the wild-type strain
achieved only 61% at the same time. The extracellular PHB depolymerase was purified from the culture medium containing PHB
as the sole carbon source by filtration, ammonium sulfate precipitation and chromatography on Sepharose CL-6B. The molecular
weight of the PHB depolymerase was about 15.1kDa determined by SDS-polyacrylamide gel electrophoresis. The optimum activity
of the PHB depolymerase was observed at pH 8.6 and 50 °C. The enzyme was stable at temperatures below 37 °C and in the pH
range from 8.0 to 9.2. The activity of PHB depolymerase could be activated or inhibited by some metal ions. The apparent K
m
value was 0.164 mg ml−1. Mass spectrometric analysis of the water-soluble products after enzymatic degradation revealed that the primary product
was the monomer, 3-hydroxybutyric acid. 相似文献