检索结果(检索关键词为:ACTIVATION;结果共22条)
  • Czarniewska, Elzbieta; Urbanski, Arkadiusz; Chowanski, Szymon; Kuczer, Mariola
    INSECT SCIENCE 2018年第25卷第3期 DOI:10.1111/1744-7917.12427
    关键词: EICOSANOID BIOSYNTHESIS INHIBITORS; MICROAGGREGATION REACTIONS; COPPER(II) COMPLEXES; IMMUNE-RESPONSES; BEET ARMYWORM; MANDUCA-SEXTA; ACTIVATION; TOLL; HEMOCYTES; STABILITY
    摘要: The subject of this article is a search for the long-term immunological effects of alloferon and 3 structural analogues of alloferon, which were earlier characterized by the highest pro-apoptotic activity in Tenebrio molitor. The differences in the actions of these peptides on immune response were observed. Alloferon increased nodulation and significantly phenoloxidase activity in the hemolymph of experimentally infected T. molitor. However, [Phe(p-NH2)(1)]- and [Phe(p-OMe)(1)]-alloferon strongly inhibited cellular and humoral defense of the mealworm against Staphylococcus aureus infection. One day after injection of these peptides, the specific biochemical and morphological hallmarks of apoptosis in bacteria-challenged hemocytes were visible; in contrast, 3 days after peptides injection in all hemocytes, caspase activation was not observed. However, these new, circulating hemocytes differed from the control and the peptide-untreated bacteria-challenged hemocytes. They had an increased adhesion that led to a separation of viable, anucleated fragments of hemocytes that retain the ability to adhere and to form long filopodia. The peptide-induced separation of hemocyte fragments may resemble the formation of platelets in mammals and perhaps play a role in sealing wounds in insects. The results of in vivo studies may suggest a long half-life of studied peptides in the hemolymph of mealworm. Moreover, we showed the importance of the N-terminal histidine residues at position one of the alloferon molecule for its immunological properties in insects. The results obtained here show that alloferon plays pleiotropic functions in insects.

  • Chen, Yue; Lewis, Robert; Curtis, J. Thomas
    Integrative Zoology 2018年第13卷第6期 DOI:10.1111/1749-4877.12306
    关键词: CESAREAN-SECTION BIRTH; SOCIAL-BEHAVIOR; PARTNER PREFERENCE; SEX-DIFFERENCES; OXYTOCIN; EXPRESSION; MANIPULATIONS; ACTIVATION; DEPRESSION; RELEVANT
    摘要: *dagger Mercury chloride exposure through drinking water in adult male prairie voles (Microtus ochrogaster) has been shown to alter their social behavior. Here, we examined the potential disruption of adult social behavior in prairie voles that were exposed to 60 ppm mercury during early development. We used a cross-fostering approach to test the effects of mercury exposure: (1) from conception until birth; (ii) from birth until weaning; and (iii) from conception until weaning, on adult affiliative behavior. Untreated and mercury-treated voles were given the option of remaining in an empty cage or affiliating with a same-sex conspecific in a 3-h choice test. We found that early developmental mercury exposure had little if any effect on the reproductive success of breeder pairs or on affiliative behavior by either sex when subjects were tested as adults. These results suggest that, at least in the context of the behavior tested, the effects of early developmental exposure to mercury do not permanently alter adult prairie vole affiliative behavior, or do so in a way that is too subtle to be detected using the current testing paradigm.

  • Chen, Congde; Wu, Suichun; Lin, Xiaokun; Wu, Dazhou; Fischbach, Shane; Xiao, Xiangwei
    CELL PROLIFERATION 2018年第51卷第3期 DOI:10.1111/cpr.12410
    关键词: N-TERMINAL KINASE; PRIMARY MECHANISM; PROTEIN-KINASES; ADULT PANCREAS; GROWTH-FACTOR; MASS; ACTIVATION; RECEPTOR; DEATH; MICE
    摘要: ObjectivesRestoring a functional beta-cell mass is a fundamental goal in treating diabetes. A complex signalling pathway network coordinates the regulation of beta-cell proliferation, although a role for ERK5 in this network has not been reported. This question was addressed in this study. Materials and methodsWe studied the activation of extracellular-signal-regulated kinase 5 (ERK5) in pregnant mice, a well-known mouse model of increased beta-cell proliferation. A specific inhibitor of ERK5 activation, BIX02189, was intraperitoneally injected into the pregnant mice to suppress ERK5 signalling. Beta-cell proliferation was determined by quantification of Ki-67(+) beta cells. Beta-cell apoptosis was determined by TUNEL assay. The extent of beta-cell proliferation was determined by beta-cell mass. The alteration of ERK5 activation and CyclinD1 levels in purified mouse islets was examined by Western blotting. ResultsExtracellular-signal-regulated kinase 5 phosphorylation, which represents ERK5 activation, was significantly upregulated in islets from pregnant mice. Suppression of ERK5 activation by BIX02189 in pregnant mice significantly reduced beta-cell proliferation, without affecting beta-cell apoptosis, resulting in increases in random blood glucose levels and impairment of glucose response of the mice. ERK5 seemed to activate CyclinD1 to promote gestational beta-cell proliferation. ConclusionsExtracellular-signal-regulated kinase 5 plays an essential role in the gestational augmentation of beta-cell proliferation. ERK5 may be a promising target for increasing beta-cell mass in diabetes patients.

  • Song, Jian; Ye, Bin; Liu, Hanghang; Bi, Ruiye; Zhang, Nian; Hu, Jing; Luo, En
    CELL PROLIFERATION 2018年第51卷第4期 DOI:10.1111/cpr.12453
    关键词: FOCAL ADHESION KINASE; STRESS-INDUCED STIMULATION; TYROSINE PHOSPHORYLATION; ENDOTHELIAL-CELLS; GENE-EXPRESSION; GROWTH; TRANSCRIPTION; PP125(FAK); ACTIVATION; INHIBITION
    摘要: Objectives: To investigate the mechanism of mechanical stimulation in bone formation and regeneration during distraction osteogenesis. Materials and methods: In this study, microarray technology was used to investigate the time course of bone-related molecular changes in distraction osteogenesis in rats. Real-time PCR and Western-blot analyses were used to confirm the expression of genes identified in microarrays. Meanwhile, we used a lentivirus vector to inhibit Fak expression, in order to identify the osteogenic effect of Fak and Fak-Mapk pathway during distraction osteogenesis. Results: Several components of the Wnt and Hippo pathways were found to be up- or down-regulated during distraction osteogenesis by microarray. Meanwhile, it was found that Fak, Src, Raf-1, Erk1, Jnk and p38-Mapk were up-regulated during gradual distraction, compared with consolidation. To further determine whether Fak-Mapk pathway played an important role in distraction osteogenesis, Fak was disrupted with a lentivirus vector. The expressions levels of p-Fak, p-Erk1/2, p-JNK and p-p38Mapk were decreased. Meanwhile, a poor early and late osteogenesis effect was found in the shRNA-Fak group. Conclusion: It was inferred that the mechanical stimulus induces increased expression of Fak and activates Fak-Mapk pathway, by activation of Erk, Jnk and p38-Mapk pathway, and that Fak at least, in part, plays an important role in maintaining osteogenic effect by activating Fak-Mapk pathway during distraction osteogenesis.

  • Park, Sangkyu; Kim, Hyewon; Kim, Kichul; Roh, Sangho
    CELL PROLIFERATION 2018年第51卷第6期 DOI:10.1111/cpr.12500
    关键词: IN-VITRO; STEM-CELLS; DIFFERENTIATION; PATHWAY; TUMORIGENICITY; ACTIVATION; GROWTH; SMO
    摘要: Objectives The sonic hedgehog (Shh) signalling pathway has an important role in the maintenance of various stem cells and organogenesis during development. However, the effect of Shh in skin-derived precursors (SKPs), which have the capacity for multipotency and self-renewal, is not yet clear. The present study investigated the effects of the Shh signalling pathway on the proliferation and self-renewal of murine SKPs (mSKPs). Methods The Shh signalling pathway was activated by treatment with purmorphamine (Shh agonist) or recombinant Shh in mSKPs. Cyclopamine (Shh antagonist) or GANT-61 (Gli inhibitor) was used to inhibit the pathway. Western blot, qPCR, and immunofluorescence were used to analyse the expression of genes related to self-renewal, stemness, epithelial-mesenchymal transition (EMT) and the Shh signalling pathway. In addition, cell proliferation and apoptosis were examined. Results Inhibiting the Shh signalling pathway reduced mSKP proliferation and sphere formation, but increased apoptosis. Activating this signalling pathway produced opposite results. The Shh signalling pathway also controlled the EMT phenotype in mSKPs. Moreover, purmorphamine recovered the self-renewal and proliferation of aged mSKPs. Conclusion Our results suggest that the Shh signalling pathway has an important role in the proliferation, self-renewal and apoptosis of mSKPs. These findings also provide a better understanding of the cellular mechanisms underlying SKP self-renewal and apoptosis that allow more efficient expansion of SKPs.