共查询到20条相似文献,搜索用时 31 毫秒
1.
Rabbit corneal cells were cultivated for 21 days and then exposed to Na235SO4, a precursor of sulfated glycosaminoglycans (GAG). All 3 cell types of the cornea, the fibroblasts, the epithelial as well as the endothelial cells, synthesize GAG. The fractionation-patterns of the epithelial and endotherlial GAG are almost identical and differ clearly from the one of fibroblastic GAG. 相似文献
2.
Effect of temperature on in vitro proliferative activity of human umbilical vein endothelial cells 总被引:2,自引:0,他引:2
Human umbilical vein endothelial cells, skin fibroblasts, and retinal pigment epithelial cells are cultivated in medium supplemented with 15 to 20% serum in our laboratory. The effects of various incubation temperatures on the proliferation of these cells was examined. Our study shows that the mitogenic response of the endothelial cells to a change of temperature differed markedly from that of the fibroblasts and epithelial cells. Cultivation of human umbilical vein endothelial at 37°C required seeding densities as high as 1–2×104 cells/cm2, and yet resulted in a low growth rate and premature senescence. However, under the same culture conditions, but at 33°C, the proliferative capacity of these endothelial cells was potentiated. The results were striking; at 33°C the cells grew actively and the life span was extended. The number of cumulative population doublings increased fourfold compared with that for the same cells cultivated at 37°C. The inoculum size could be reduced, since at 33°C the endothelial cells were able to replicate at seeding densities as low as 20 cells/cm2. The cells serially subcultured at 33°C retained morphological features and specific immunological markers of endothelial cells. 相似文献
3.
Mitchell Y. Sun Melissa Geyer Yulia A. Komarova 《Cellular and molecular life sciences : CMLS》2017,74(22):4189-4207
The endothelium, a monolayer of endothelial cells lining vessel walls, maintains tissue-fluid homeostasis by restricting the passage of the plasma proteins and blood cells into the interstitium. The ion Ca2+, a ubiquitous secondary messenger, initiates signal transduction events in endothelial cells that is critical to control of vascular tone and endothelial permeability. The ion Ca2+ is stored inside the intracellular organelles and released into the cytosol in response to environmental cues. The inositol 1,4,5-trisphosphate (IP3) messenger facilitates Ca2+ release through IP3 receptors which are Ca2+-selective intracellular channels located within the membrane of the endoplasmic reticulum. Binding of IP3 to the IP3Rs initiates assembly of IP3R clusters, a key event responsible for amplification of Ca2+ signals in endothelial cells. This review discusses emerging concepts related to architecture and dynamics of IP3R clusters, and their specific role in propagation of Ca2+ signals in endothelial cells. 相似文献
4.
E. P. C. Kilsdonk A. N. R. D. Dorsman A. van Tol 《Cellular and molecular life sciences : CMLS》1993,49(6-7):561-566
EA.hy 926 cells, a human endothelial cell line, show characteristics of differentiated endothelial cells. The cells express saturable binding of apo E-free125I-high density lipoprotein3 (HDL3). Bmax increased from 71 to 226 ng HDL3 bound/mg cell protein after cholesterol loading of the confluent endothelial cells with cationized low density lipoprotein (LDL). The affinity did not change after cholesterol enrichment (Kd was 37 g HDL3 protein/ml for control cells and 31 g/ml, for loaded cells). Incubation of cholesterol-loaded EA.hy 926 cells with native HDL and LDL had different effects on cellular cholesterol levels. Incubation with HDL decreased both esterified and unesterified cellular cholesteryl, but LDL did not change total cellular cholesterol However, LDL tended to increase cellular cholesteryl esters, with a concomitant decrease of unesterified, cellular cholesterol. Incubation of endothelial cells with both HDL and LDL also resulted in decreased total cellular cholesterol levels. These data show that cationized LDL-loaded human endothelial EA.hy 926 cells can be used to study the net transport of cellular cholesterol to HDL, the first step in reverse cholesterol transport. 相似文献
5.
R. G. MacDonald R. H. McCusker D. J. Blackwood J. A. Vanderhoof J. H. Y. Park 《Cellular and molecular life sciences : CMLS》1998,54(2):158-166
To determine if intestinal stromal cells secrete diffusible factors such as insulin-like growth factors (IGFs) capable of
regulating epithelial cell growth in vitro, stromal cells were isolated by enzymatic digestion of rat intestine. Incorporation
of [3H]thymidine into DNA and [14C]leucine into protein of IEC-6 cells, a model intestinal epithelial cell line, was significantly increased (two- to threefold)
when the IEC-6 cells were co-cultured with stromal cells, relative to IEC-6 cells grown alone. Medium conditioned by stromal
cells stimulated DNA synthesis of IEC-6 cells in a dose-dependent manner. Analysis of the conditioned medium revealed that
intestinal stromal cells secreted IGF-I, but little IGF-II, in addition to an M
r 32,000 IGF-binding protein (IGFBP-2) and an IGFBP having M
r∼ 24,000. We conclude that rat intestinal stromal cells secrete one or more diffusible factors, which may include IGF-I and
IGFBPs, capable of stimulating proliferation of IEC-6 cells in vitro.
Received 25 August 1997; received after revision 7 November 1997; accepted 20 November 1997 相似文献
6.
B. Lindblad W. E. Burkel T. W. Wakefield L. M. Graham J. C. Stanley 《Cellular and molecular life sciences : CMLS》1988,44(3):223-224
Summary The most important effect of dihydroergotamine is venoconstriction, but certain metabolic effects and changes in vessel prostanoid activity have also been suggested. In this study endothelial cell production of 6-keto PGF1 and TxB2 was quantitated in vitro. No evidence of altered prostanoid production was noted after incubation with dihydroergotamine (exposure ranging from 5×10–3 to 5×10–7 g/l). Similarly, no effect of dihydroergotamine on the growth rates of endothelial cells or smooth muscle cells in vitro was documented. 相似文献
7.
Marko Kreft Miha Lukšič Tomaž M. Zorec Mateja Prebil Robert Zorec 《Cellular and molecular life sciences : CMLS》2013,70(8):1483-1492
Astrocytes interact with neurons and endothelial cells and may mediate exchange of metabolites between capillaries and nerve terminals. In the present study, we investigated intracellular glucose diffusion in purified astrocytes after local glucose uptake. We used a fluorescence resonance energy transfer (FRET)-based nano sensor to monitor the time dependence of the intracellular glucose concentration at specific positions within the cell. We observed a delay in onset and kinetics in regions away from the glucose uptake compared with the region where we locally super-fused astrocytes with the d-glucose-rich solution. We propose a mathematical model of glucose diffusion in astrocytes. The analysis showed that after gradual uptake of glucose, the locally increased intracellular glucose concentration is rapidly spread throughout the cytosol with an apparent diffusion coefficient (D app) of (2.38 ± 0.41) × 10?10 m2 s?1 (at 22–24 °C). Considering that the diffusion coefficient of d-glucose in water is D = 6.7 × 10?10 m2 s?1 (at 24 °C), D app determined in astrocytes indicates that the cytosolic tortuosity, which hinders glucose molecules, is approximately three times higher than in aqueous solution. We conclude that the value of D app for glucose measured in purified rat astrocytes is consistent with the view that cytosolic diffusion may allow glucose and glucose metabolites to traverse from the endothelial cells at the blood–brain barrier to neurons and neighboring astrocytes. 相似文献
8.
Porcelli AM Ghelli A Mastrocola T Rugolo M 《Cellular and molecular life sciences : CMLS》1999,56(1-2):167-173
The Ca2+ ionophore ionomycin induced cytosolic [Ca2+]i elevation as well as strong activation of Cl− efflux in mouse mammary epithelial cell lines expressing wild-type or mutated (deletion of phenylalaline 508) cystic fibrosis
transmembrane conductance regulator (CFTR) or vector. Ionomycin-induced Cl− efflux was abolished by the intracellular Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid, whereas both activators and inhibitors of phospholipase A2 had no effect, indicating the involvement of Ca2+-dependent Cl- channels. Stimulation of arachidonic acid release by ionomycin and phorbol ester was not significantly different between
wild-type or mutated cell lines, whereas vector-transfected cells exhibited a significant higher release, which was shown
to be due to larger amount of immunoreactive cytosolic phospholipase A2. These results indicate that phospholipase A2 activity of C127 cells was not influenced by the presence of wild-type or mutated CFTR.
Received 27 April 1999; received after revision 11 June 1999; accepted 23 July 1999 相似文献
9.
A VEGF-A splice variant defective for heparan sulfate and neuropilin-1 binding shows attenuated signaling through VEGFR-2 总被引:1,自引:0,他引:1
Cébe Suarez S Pieren M Cariolato L Arn S Hoffmann U Bogucki A Manlius C Wood J Ballmer-Hofer K 《Cellular and molecular life sciences : CMLS》2006,63(17):2067-2077
The development of functional blood and lymphatic vessels requires spatio-temporal coordination of the production and release
of growth factors such as vascular endothelial growth factors (VEGFs). VEGF family proteins are produced in multiple isoforms
with distinct biological properties and bind to three types of VEGF receptors. A VEGF-A splice variant, VEGF-A165b, has recently been isolated from kidney epithelial cells. This variant is identical to VEGF-A165 except for the last six amino acids encoded by an alternative exon. VEGF-A165b and VEGF-A165 bind VEGF receptors 1 and 2 with similar affinity. VEGF-A165b elicits drastically reduced activity in angiogenesis assays and even counteracts signaling by VEGF-A165. VEGF-A165b weakly binds to heparan sulfate and does not interact with neuropilin-1, a coreceptor for VEGF receptor 2. To determine
the molecular basis for altered signaling by VEGF-A165b we measured VEGF receptor 2 and ERK kinase activity in endothelial cells in culture. VEGF-A165 induced strong and sustained activation of VEGF receptor 2 and ERK-1 and −2, while activation by VEGF-A165b was only weak and transient. Taken together these data show that VEGF-A165b has attenuated signaling potential through VEGF receptor 2 defining this new member of the VEGF family as a partial receptor
agonist.
Received 31 May 2006; received after revision 26 June 2006; accepted 14 July 2006 相似文献
10.
Chérine Bechara Manjula Pallerla Fabienne Burlina Françoise Illien Sophie Cribier Sandrine Sagan 《Cellular and molecular life sciences : CMLS》2015,72(4):809-820
Among non-invasive cell delivery strategies, cell-penetrating peptide (CPP) vectors represent interesting new tools. To get fundamental knowledge about the still debated internalisation mechanisms of these peptides, we modified the membrane content of cells, typically by hydrolysis of sphingomyelin or depletion of cholesterol from the membrane outer leaflet. We quantified and visualised the effect of these viable cell surface treatments on the internalisation efficiency of different CPPs, among which the most studied Tat, R9, penetratin and analogues, that all carry the N-terminal biotin-Gly4 tag cargo. Under these cell membrane treatments, only penetratin and R6W3 underwent a massive glycosaminoglycan (GAG)-dependent entry in cells. Internalisation of the other peptides was only slightly increased, similarly in the absence or the presence of GAGs for R9, and only in the presence of GAGs for Tat and R6L3. Ceramide formation (or cholesterol depletion) is known to lead to the reorganisation of membrane lipid domains into larger platforms, which can serve as a trap and cluster receptors. These results show that GAG clustering, enhanced by formation of ceramide, is efficiently exploited by penetratin and R6W3, which contains Trp residues in their sequence but not Tat, R9 and R6L3. Hence, these data shed new lights on the differences in the internalisation mechanism and pathway of these peptides that are widely used in delivery of cargo molecules. 相似文献
11.
D. Parolini M. Meregalli M. Belicchi P. Razini R. Lopa B. Del Carlo A. Farini S. Maciotta N. Bresolin L. Porretti M. Pellegrino Y. Torrente 《Cellular and molecular life sciences : CMLS》2009,66(4):697-710
Among the heterogeneous population of circulating hematopoietic and endothelial progenitors, we identified a subpopulation
of CD133+ cells displaying myogenic properties. Unexpectedly, we observed the expression of the B-cell marker CD20 in blood-derived
CD133+ stem cells. The CD20 antigen plays a role in the modulation of intracellular calcium homeostasis through signaling pathways
activation. Several observations suggest that an increase in intracellular calcium concentration ([Ca2+]i) could be involved in the etiology of the Duchenne muscular dystrophy (DMD). Here, we show that a CD20-related signaling
pathway able to induce an increase in [Ca2+]i is differently activated after brain derived neurotrophic factor (BDNF) stimulation of normal and dystrophic blood-derived
CD133+ stem cells, supporting the assumption of a “CD20-related calcium impairment-affecting dystrophic cells. Presented findings
represent the starting point toward the expansion of knowledge on pathways involved in the pathology of DMD and in the behavior
of dystrophic blood-derived CD133+ stem cells.
Received 15 October 2008; received after revision 27 November 2008; accepted 05 December 2008 相似文献
12.
13.
Su Feng Wei Chen Dan Cao Jinjun Bian Fang-Yuan Gong Wei Cheng Shun Cheng Qiang Xu Zi-Chun Hua Wu Yin 《Cellular and molecular life sciences : CMLS》2011,68(1):109-124
Increasing evidence demonstrates that Na+, K+-ATPase plays an important role in pulmonary inflammation, but the mechanism remains largely unknown. In this study, we used
cardiotonic steroids as Na+, K+-ATPase inhibitors to explore the possible involvement of Na+, K+-ATPase in pulmonary epithelial inflammation. The results demonstrated that mice after ouabain inhalation developed cyclooxygenase-2-dependent
acute lung inflammation. The in vitro experiments further confirmed that Na+, K+-ATPase inhibitors significantly stimulated cyclooxygenase-2 expression in lung epithelial cells of human or murine origin,
the process of which was participated by multiple cis-elements and trans-acting factors. Most importantly, we first described here that Na+, K+-ATPase inhibitors could evoke a significant Hu antigen R nuclear export in lung epithelial cells, which stabilized cyclooxygenase-2
mRNA by binding with a proximal AU-rich element within its 3′-untranslated region. In conclusion, HuR-mediated mRNA stabilization
opens new avenues in understanding the importance of Na+, K+-ATPase, as well as its inhibitors in inflammation. 相似文献
14.
Schaefer U Schneider A Rudroff C Neugebauer E 《Cellular and molecular life sciences : CMLS》2003,60(9):1968-1981
During agonist-dependent long-term stimulation of cells, histamine receptor subtypes are frequently down-regulated. However, the mechanisms underlying the modulation of receptor expression during long-term histamine stimulation have yet to be resolved. Based on our recently reported results showing an H1-mediated down-regulation of histamine H2 receptor mRNA in endothelial cells, our aim was to characterize the mechanism controlling rapid and long-term histamine-mediated modulation of H2 receptor expression in more detail. We were able to show that the histamine-induced down-regulation of H2 receptor mRNA and cell surface expression lasting for 24 h was accompanied by augmentation of the receptor protein level in the cytoplasmatic fraction of endothelial cells for this time period. Furthermore, changes in receptor protein levels in whole-cell lysate were negligible, indicating that the rapid and prolonged modulation of cell surface H2 receptor levels by histamine was regulated solely via internalization. The role of nitric oxide (NO) as a key mediator in histamine-stimulated cell responses was underlined by subsequent studies showing the attenuation of histamine-induced H2 receptor mRNA down-regulation and protein trafficking following NO synthase isozyme inhibition.Received 11 March 2003; received after revision 11 June 2003; accepted 17 June 2003 相似文献
15.
M. Takei A. Umeyama N. Shoji S. Arihara K. Endo 《Cellular and molecular life sciences : CMLS》1993,49(2):145-149
Histamine release from rat peritoneal mast cells induced by anti-IgE was essentially complete within 4–5 min. Xestobergsterol A and B, which are constituents of the Okinawan marine spongeXestospongia bergquistia Fromont, dose-dependently inhibited anti-IgE-induced histamine release from rat mast cells. The IC50 values of xestobergsterol A and B for histamine release in mast cells activated by anti-IgE were 0.07 and 0.11 M, respectively. Anti-IgE stimulated PI-PLC activity in a mast cell membrane preparation. Xestobergsterol A dose-dependently inhibited the generation of IP3 and membrane-bound PI-PLC activity. Moreover, xestobergsterol A inhibited Ca2+-mobilization from intracellular Ca2+-stores as well as histamine release in mast cells activated by anti-IgE. On the other hand, xestobergsterol B did not inhibit the membrane-bound and cytosolic PI-PLC activity, IP3 generation or the initial rise in [Ca2+]i in mast cells activated by anti-IgE. These results suggest that the mechanism of inhibition by xestobergsterol A of the initial rise in [Ca2+]i, of the generation of IP3, and of histamine release induced by anti-IgE, was through the inhibition of PI-PLC activity. 相似文献
16.
R. B. Bajnath J. A. Groot H. R. de Jonge M. Kansen J. Bijman 《Cellular and molecular life sciences : CMLS》1993,49(4):313-316
In excised inside-out membrane patches of the human colon carcinoma HT-29cl.19A cells a large conductance (373±10 pS) chloride channel was found. Channel activity could only be observed after excision of patches from cells incubated with calcium ionophore. The channel was never observed in cell-attached patches. The channel was strongly voltage dependent, being open only between +30 and –30 mV clamp potentials. The selectivity sequence among anions, deduced from reversal potentials, was I>Br>Cl>F>gluconate. The PNa/PCl was 0.09. Although a similar type of channel, has been described earlier, this is the first report stating its appearance in patches of intestinal epithelial cells requiring the combined action of Ca2+ ionophore and excision, suggesting its control by an intracellular compound. 相似文献
17.
R. Van Buskirk 《Cellular and molecular life sciences : CMLS》1977,33(4):438-439
Summary Mechanical injury initself may be responsible for the transition of lens epithelial cells from the G0 to the G1 compartment of the cell cycle. This traverse which does not depend on DNA-dependent hypophysial hormones may be in part reversible. 相似文献
18.
Mesenchymoangioblast (MB) is the earliest precursor for endothelial and mesenchymal cells originating from APLNR+PDGFRα+KDR+ mesoderm in human pluripotent stem cell cultures. MBs are identified based on their capacity to form FGF2-dependent compact spheroid colonies in a serum-free semisolid medium. MBs colonies are composed of PDGFRβ+CD271+EMCN+DLK1+CD73? primitive mesenchymal cells which are generated through endothelial/angioblastic intermediates (cores) formed during first 3–4 days of clonogenic cultures. MB-derived primitive mesenchymal cells have potential to differentiate into mesenchymal stromal/stem cells (MSCs), pericytes, and smooth muscle cells. In this review, we summarize the specification and developmental potential of MBs, emphasize features that distinguish MBs from other mesenchymal progenitors described in the literature and discuss the value of these findings for identifying molecular pathways leading to MSC and vasculogenic cell specification, and developing cellular therapies using MB-derived progeny. 相似文献
19.
Summary Phospholipase digestion of rat intestinal epithelial cell membranes was performed in order to study the influence of membrane phospholipids on the binding activity of VIP receptors. Phospholipases A2 and C strougly (ED504×10–2 and 4×10–1 g/ml, respectively) and rapidly reduced125I-VIP binding to membranes whereas phospholipase D was ineffective. This suggests an important role of both hydrophobic and hydrophilic groups of phospholipids on VIP receptor binding activity.This work was supported by INSERM (CRL 827017) and the Fondation pour la Recherche Médicale Française. 相似文献
20.
Ramasri Sathanoori Paulina Bryl-Gorecka Christa E. Müller Laurie Erb Gary A. Weisman Björn Olde David Erlinge 《Cellular and molecular life sciences : CMLS》2017,74(4):731-746
Endothelial cells release ATP in response to fluid shear stress, which activates purinergic (P2) receptor-mediated signaling molecules including endothelial nitric oxide (eNOS), a regulator of vascular tone. While P2 receptor-mediated signaling in the vasculature is well studied, the role of P2Y2 receptors in shear stress-associated endothelial cell alignment, cytoskeletal alterations, and wound repair remains ill defined. To address these aspects, human umbilical vein endothelial cell (HUVEC) monolayers were cultured on gelatin-coated dishes and subjected to a shear stress of 1 Pa. HUVECs exposed to either P2Y2 receptor antagonists or siRNA showed impaired fluid shear stress-induced cell alignment, and actin stress fiber formation as early as 6 h. Similarly, when compared to cells expressing the P2Y2 Arg-Gly-Asp (RGD) wild-type receptors, HUVECs transiently expressing the P2Y2 Arg-Gly-Glu (RGE) mutant receptors showed reduced cell alignment and actin stress fiber formation in response to shear stress as well as to P2Y2 receptor agonists in static cultures. Additionally, we observed reduced shear stress-induced phosphorylation of focal adhesion kinase (Y397), and cofilin-1 (S3) with receptor knockdown as well as in cells expressing the P2Y2 RGE mutant receptors. Consistent with the role of P2Y2 receptors in vasodilation, receptor knockdown and overexpression of P2Y2 RGE mutant receptors reduced shear stress-induced phosphorylation of AKT (S473), and eNOS (S1177). Furthermore, in a scratched wound assay, shear stress-induced cell migration was reduced by both pharmacological inhibition and receptor knockdown. Together, our results suggest a novel role for P2Y2 receptor in shear stress-induced cytoskeletal alterations in HUVECs. 相似文献