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101.
目的:研究人早孕绒毛组织中磷酸化的细胞外信号调节蛋白激酶(p-ERK)的表达水平,探讨流产及其有关生殖过程发生的分子机制。方法:采用免疫组织化学、图像分析方法检测30例正常早孕绒毛组织(正常早孕组)和30例自然流产的早孕绒毛组织(自然流产组)中p-ERK的表达水平。结果:人早孕绒毛细胞滋养细胞、合体滋养细胞均有p-ERK的表达,自然流产组中p-ERK蛋白表达面积及强度均明显低于正常早孕组,两者差异有显著性意义(P<0.05)。结论:ERK/MAPK(丝裂原活化蛋白激酶)通路可能是人早孕绒毛滋养细胞增殖、分化及侵入过程中的主要信号转导途径之一。 相似文献
102.
电针任脉联合bFGF对脑缺血大鼠ERK通路的调节作用 总被引:4,自引:0,他引:4
目的:研究电针任脉联合碱性成纤维细胞生长因子(bFGF)对局灶性脑缺血细胞外信号调节激酶(ERK)通路的调节作用。方法:线栓法制作大鼠大脑中动脉栓塞(MCAO)模型。通过Western blot方法研究各组ERK1/2表达和磷酸化的活性特征。结果:MCAO电针联合bFGF治疗后14d,ERK1/2表达在局灶缺血大鼠脑组织中即开始显著升高,ERK1/2磷酸化水平在MCAO后7d开始提高。结论:电针任脉联合bFGF对大鼠局灶性脑缺血的ERK通路起着重要的调节作用,电针任脉联合bFGF治疗对缺血性脑损伤有一定保护作用。 相似文献
103.
Rab10蛋白作为Rab鸟苷三磷酸酶家族成员之一,不仅参与细胞内囊泡的形成、转运、锚定和融合过程,同时也影响肿瘤的发生发展.通过对Rab10在细胞内囊泡运输和肿瘤中的机制研究,可能为抗肿瘤治疗提供潜在的靶点和新思路. 相似文献
104.
目的检测急性早幼粒白血病细胞HL-60经过淫羊藿甙(ICA)诱导后信号传导与转录激活因子(STAT1、STAT3)和有丝分裂原激活蛋白激酶(p38MAPK、p42MAPK)表达变化在分化中的作用。方法建立ICA诱导分化模型,用瑞氏染色观察细胞形态,MTT实验测定细胞增殖的变化,NBT还原实验测定细胞分化状态,RT-PCR方法检测STAT1、STAT3、p38MAPK、p42MAPK 的mRNA的表达。结果 HL-60细胞经ICA作用24 h后,随着细胞增殖降低和分化的发生, p42MAPK的mRNA表达增加,STAT3的mRNA表达降低,STAT1和p38MAPK的mRNA未见明显的表达。结论 p42MAPK和STAT3与ICA诱导HL-60细胞分化有关,而p38MAPK和STAT1则与ICA诱导HL-60细胞分化无关。 相似文献
105.
Mohamed S A Gaballah Hamdy E A Ali Zeinab A Hassan Shahenda Mahgoub Hamid I Ali Johng S Rhim Mourad Zerfaoui Khalid A El Sayed David Stephen Paul W Sylvester Zakaria Y Abd Elmageed 《American journal of cancer research》2022,12(8):4015
Early diagnosis and treatment of patients with aggressive prostate cancer (PCa) remains a clinically unmet need. We aimed to determine the levels of small extracellular vesicle (sEV)-associated microRNAs (miRs); miR-4737, miR-6068, and miR-6076 in a large panel of PCa cells and delineate the biological significance of miR-6068 in promoting PCa cells. sEVs were isolated from the conditioned medium of PCa cells, followed by RNA extraction and quantitative Real-Time PCR analysis. Functional assays were performed, and the protein expression of hypermethylated in cancer 2 (HIC2), as a potential miR-6068 target gene, was evaluated in PCa tissues by immunohistochemistry. sEV-associated miR-6068, miR-4737, and miR-6076 levels displayed large and significant differences compared to normal cells. miR-6068 was explicitly upregulated in sEV of PC-3 and CWR-R1ca cells (P<0.010). Suppression of miR-6068 in CWR-R1ca cells decreased cell proliferation, colony formation, and cell migration. In contrast, upregulation of miR-6068 in RC77T/E cells decreased HIC2 levels and increased cell aggressive phenotypes. The overexpression of HIC2 in PCa tissues was primarily observed in the cytoplasm compared to benign prostatic hyperplasia (BPH) and normal tissues (P<0.0001). This study confirms the differential packaging of miR-4737, miR-6068, and miR-6076 in sEVs of PCa cells. MiR-6068 promotes PCa cells to acquire aggressive phenotypes by inhibiting the HIC2/Sirtuin 1 (SIRT1) axis. 相似文献
106.
Han-Yu Chen Xin-Yu Wang Ke-Ming Lu Chen-Hsiang Yu Mei-Tsz Su Lin Kang Keng-Fu Hsu Po-Fan Chen Sheng-Hsiang Lin 《International journal of medical sciences》2022,19(11):1672
Preeclampsia is one of the most serious pregnancy complications. It may be caused by immunological changes in the early placental microenvironment. The contents of small EVs may serve as biomarkers of pregnancy complications. Evidence suggests that the balance between T helper 17 (Th17) and regulatory T (Treg) cells are critical for preventing preeclampsia. The study recruited 39 pregnant women with preeclampsia and 127 healthy pregnant women. We assessed the levels of both Th17 and Treg cytokines (IL-10, IL-17, IL-21, IL-22, and TGF-β) in their plasma and small EVs. We found significant differences in the levels of all cytokines in the plasma between the two groups during the second trimester. We also observed significant differences between the two groups in the levels of EV-encapsulated cytokines IL-21, IL-22, and TGF-β, as well as in total small EVs, during the second trimester. The ROC analysis showed that the classification efficiency (AUC) of TGF-β in small EVs was 0.81. TGF-β had the best discriminant ability of all the single EV biomarkers tested, the cross-validation of the accuracy was 0.89. Th17 and Treg cytokines in plasma and small EVs may contribute to maternal immune activation and clarify the potential mechanisms of small EVs and cytokines in preeclampsia. 相似文献
107.
Teja Srinivas Nirujogi Sainath R. Kotha Sangwoon Chung Brenda F. Reader Anita Yenigalla Liwen Zhang John P. Shapiro Jon Wisler John W. Christman Krishnarao Maddipati Narasimham L. Parinandi Manjula Karpurapu 《Journal of innate immunity》2022,14(5):555
Emerging data support the pivotal role of extracellular vesicles (EVs) in normal cellular physiology and disease conditions. However, despite their abundance, there is much less information about the lipid mediators carried in EVs, especially in the context of acute lung injury (ALI). Our data demonstrate that C57BL/6 mice subjected to intranasal Escherichia coli lipopolysaccharide (LPS)-induced ALI release, a higher number of EVs into the alveolar space, compared to saline-treated controls. EVs released during ALI originated from alveolar epithelial cells, macrophages, and neutrophils and carry a diverse array of lipid mediators derived from ω-3 and ω-6 polyunsaturated fatty acids (PUFA). The eicosanoids in EVs correlated with cellular levels of arachidonic acid, expression of cytosolic phospholipase A2, cyclooxygenase (COX), lipoxygenase (LOX), and cytochrome epoxygenase p450 proteins in pulmonary macrophages. Furthermore, EVs from LPS-toll-like receptor 4 knockout (TLR4<sup>-/-</sup>) mice contained significantly lower amounts of COX and LOX catalyzed eicosanoids and ω-3 PUFA metabolites. More importantly, EVs from LPS-treated wild-type mice increased TNF-α release by macrophages and reduced alveolar epithelial monolayer barrier integrity compared to EVs from LPS-treated TLR4<sup>−/−</sup> mice. In summary, our study demonstrates for the first time that the EV carried PUFA metabolite profile in part depends on the inflammatory status of the lung macrophages and modulates pulmonary macrophage and alveolar epithelial cell function during LPS-induced ALI. 相似文献
108.
Maria Ejma Natalia Madetko Anna Brzecka Piotr Alster Sawomir Budrewicz Magdalena Koszewicz Marta Misiuk-Hojo Irina K. Tomilova Siva G. Somasundaram Cecil E. Kirkland 《Current Neuropharmacology》2022,20(3):630
Background: Stroke is a major challenge in neurology due to its multifactorial genesis and irreversible consequences. Processes of endogenous post-stroke neurogenesis, although insufficient, may indicate possible direction of future therapy. Multiple research considers stem-cell-based approaches in order to maximize neuroregeneration and minimize post-stroke deficits. Objective: Aim of this study is to review current literature considering post-stroke stem-cell-based therapy and possibilities of inducing neuroregeneration after brain vascular damage. Methods: Papers included in this article were obtained from PubMed and MEDLINE databases. The following medical subject headings (MeSH) were used: “stem cell therapy”, “post-stroke neurogenesis”, “stem-cells stroke”, “stroke neurogenesis”, “stroke stem cells”, “stroke”, “cell therapy”, “neuroregeneration”, “neurogenesis”, “stem-cell human”, “cell therapy in human”. Ultimate inclusion was made after manual review of the obtained reference list. Results: Attempts of stimulating neuroregeneration after stroke found in current literature include supporting endogenous neurogenesis, different routes of exogenous stem cells supplying and extracellular vesicles used as a method of particle transport. Conclusion: Although further research in this field is required, post stroke brain recovery supported by exogenous stem cells seems to be promising future therapy revolutionizing modern neurology. 相似文献
109.
《药学学报(英文版)》2022,12(5):2171-2192
The mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway is widely activated by a variety of extracellular stimuli, and its dysregulation is associated with the proliferation, invasion, and migration of cancer cells. ERK1/2 is located at the distal end of this pathway and rarely undergoes mutations, making it an attractive target for anticancer drug development. Currently, an increasing number of ERK1/2 inhibitors have been designed and synthesized for antitumor therapy, among which representative compounds have entered clinical trials. When ERK1/2 signal transduction is eliminated, ERK5 may provide a bypass route to rescue proliferation, and weaken the potency of ERK1/2 inhibitors. Therefore, drug research targeting ERK5 or based on the compensatory mechanism of ERK5 for ERK1/2 opens up a new way for oncotherapy. This review provides an overview of the physiological and biological functions of ERKs, focuses on the structure–activity relationships of small molecule inhibitors targeting ERKs, with a view to providing guidance for future drug design and optimization, and discusses the potential therapeutic strategies to overcome drug resistance. 相似文献
110.
E. Petzinger G. Burckhardt M. Schwenk H. Faulstich 《Naunyn-Schmiedeberg's archives of pharmacology》1982,320(2):196-200
Summary Several earlier studies suggested that the uptake of phallotoxins by liver cells is a carrier mediated process using a transport system normally handling bile acids (see Frimmer 1982). In this study we have shown whether ileal cells, well known to transport bile acids too, are able to take up phallotoxins. Isolated epithelial cells prepared from guinea pig ileum accumulated [14C]-cholate, whereas [3H]-demethylphalloin ([3H]-DMP) was not taken up. The same observation was made with isolated jejunal cells but the uptake of [14C]-cholate was much slower. [3H]-DMP, however, was partly bound to intestinal cells. This process was not inhibited by cholate, iodipamide, oligomycin and carbonylcyano-chlorophenylhydrazone (CCCP), compounds known to decrease the uptake of phallotoxins into liver cells. Substituting Na+ for choline+ and also Cl– for SCN– did not influence the binding of [3H]-DMP. Frozen intestinal cells from the guinea pig bound two times more [3H]-DMP after thawing compared with intact cells. Supplementary uptake experiments on isolated brush border membrane vesicles from rat ileum revealed that phalloidin does not inhibit taurocholate uptake and that taurocholate does not interfer with [3H]-DMP binding.The results suggest that [3H]-demethylphalloin is not recognized by the bile acid carrier of the guinea pig and the rat ileum. It is concluded that the transport system for bile acids present in ileal cells is different from that of liver cells.Abbreviations TC
taurocholic acid
- DMP
demethylphalloin
- CCCP
carbonylcyano-chlorophenylhydrazone
- EGTA
ethylene-glycol-bis-(2-aminoethylether)-N,N-tetraacetic acid
- FCCP
carbonylcyano-p-trifluoromethoxyphenylhydrazine
This work was supported by the Deutsche Forschungsgemeinschaft 相似文献