Changes in Red Blood Cell Membrane Properties: The Role of Metabolic Syndrome Components

Metabolic syndrome (MetS) is a cluster of metabolic, hormonal and hemodynamic disorders that contribute to a change in the structural and functional status of erythrocytes and contribute to dysregulation of their cation transport function, where Ca2+ -dependent potassium channels (KCa channels) play an important role. A MetS model was performed using male Wistar rats, which were divided into control and experimental groups. Rats in the control group were fed standard rat chow. Rats in the experimental group were exposed to a high-fat and high-carbohydrate (HFHC) diet for 12 weeks. The data obtained indicate that the HFHC diet led to obesity, high blood pressure, hyperglycemia, impaired glucose tolerance, and dyslipidemia. The level of glutathione (GSH) decreased in the erythrocytes of rats suffering from MetS, but the level of malondialdehyde (MDA) increased. It was shown that the amplitude of the membrane potential of erythrocytes of rats with MetS changed depending on the acting agent: when stimulated with calcium ionophore A23187 it decreased, when the redox system ascorbat –phenazine methosulfate was used, it increased compared to the control group. The data obtained indicate that a HFHC diet leads to changes in the physical and chemical properties of the erythrocyte membrane.

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Characterization of the megakaryocyte secretory response: studies of continuously monitored release of endogenous ATP

Blood ◽

10.1182/blood.v61.5.967.967 ◽

1983 ◽

Vol 61 (5) ◽

pp. 967-972 ◽

Cited By ~ 10

Author(s):

JL Miller

Keyword(s):

Guinea Pig ◽

Blood Platelets ◽

Atp Release ◽

Chemical Properties ◽

Calcium Ionophore ◽

Calcium Ionophore A23187 ◽

Ionophore A23187 ◽

Storage Pool ◽

Functional Aspects ◽

Absolute Requirement

Abstract Megakaryocytes share a number of structural and chemical properties with their progeny, blood platelets. With the availability of highly purified preparations of megakaryocytes isolated from guinea pig bone marrow, it is now also possible to study functional aspects of these cells. The present work reports the first study of the release of endogenously stored materials in megakaryocytes. Guinea pig megakaryocytes isolated to 75%-90% purity were exposed to thrombin or calcium ionophore (A23187) and the release of ATP was continuously monitored with the luciferin-luciferase reaction. Both maximal extent and initial rate of release were studied. Thrombin-induced release was half-maximal at thrombin concentrations of 0.2–0.5 NIH U/ml. At 4 U/ml thrombin, maximal release was 538 +/- 147 nmole ATP/10(9) megakaryocytes. A23187 induced half-maximal responses at concentrations of 7–8 microM. ATP release by ionophore showed a nearly absolute requirement for extracellular calcium, with release by thrombin showing only a partial calcium dependence. Following overnight culture, the response to thrombin was unchanged, whereas ATP release in response to ionophore was consistently increased (p less than 0.01). By comparison of maximally releasable ATP with total cellular ATP content, the storage pool of ATP in megakaryocytes was determined to comprise only 2%-6% of total megakaryocyte ATP, in contrast to an ATP storage pool of 20%-30% in guinea pig platelets. This difference may reflect further entry of ATP into the storage pool compartment or an enhanced ability of the cell to recognize and respond fully to platelet stimuli as the megakaryocyte reaches full maturity.

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A combination of calcium ionophore and puromycin effectively produces human parthenogenones with one haploid pronucleus

Zygote ◽

10.1017/s0967199401001083 ◽

2001 ◽

Vol 9 (1) ◽

pp. 83-88 ◽

Cited By ~ 29

Author(s):

Koji Nakagawa ◽

Shuji Yamano ◽

Hisayo Nakasaka ◽

Kenji Hinokio ◽

Midori Yoshizawa ◽

...

Keyword(s):

Polar Body ◽

Calcium Ionophore ◽

Calcium Ionophore A23187 ◽

Control Group ◽

Ionophore A23187 ◽

Cleavage Rate ◽

Parthenogenetic Activation ◽

Second Polar Body ◽

Activation Rates ◽

Pronuclear Formation

Parthenogenetic activation with various combinations of the calcium ionophore A23187 and protein synthesis or phosphorylation inhibitors was investigated as a means of producing human parthenogenones with one haploid pronucleus. Unfertilised human aged oocytes exposed to 5 μM A23187 for 5 min were treated with 10 μg/ml puromycin (puromycin group, 46 oocytes) or 2 mM 6-dimethylaminopurine (DMAP group, 42 oocytes) for 5 h. Oocytes treated only with A23187 served as a control (control group, 40 oocytes). After washing the oocytes, they were incubated for up to 37 h. Evidence of activation (pronuclear formation) and cleavage was observed 18 h and 42 h after A23187 treatment, respectively. Activation rates in the puromycin and DMAP groups were significantly higher than in the control group (91% (42/46) and 77% (34/44) vs 20% (8/40), p < 0.05, respectively). In the puromycin group, 81% (34/42) of the activated oocytes showed one pronucleus with the second polar body (2ndPB), whereas none (0/34) of the activated oocytes in the DMAP group extruded the 2ndPB. The cleavage rate in the puromycin group was significantly lower than in the DMAP group (38% vs 68%, p < 0.05). The activated oocytes which had one pronucleus with the 2ndPB in the puromycin group showed a haploid set of chromosomes (10/13). In conclusion, the combination of A23187 and puromycin is effective for producing human parthenogenones with one haploid pronucleus.

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Chronically Impaired Endothelial Vasoreactivity Following Oversized Endovascular Introducer Sheath Placement in Porcine Iliac Arteries: Implications for Endovascular Therapy

Vascular ◽

10.2310/6670.2006.00060 ◽

2006 ◽

Vol 14 (6) ◽

pp. 353-361 ◽

Cited By ~ 2

Author(s):

Peter H. Lin ◽

James L. Steinberg ◽

Tamuru Okada ◽

Wei Zhou ◽

Hosam F. El Sayed ◽

...

Keyword(s):

Endothelial Dysfunction ◽

Endothelial Function ◽

Time Course ◽

Calcium Ionophore ◽

Calcium Ionophore A23187 ◽

Control Group ◽

Ionophore A23187 ◽

Introducer Sheath ◽

Iliac Arteries ◽

Endovascular Prosthesis

The conventional endovascular aortic aneurysm procedure entails the placement of oversized introducer sheaths in relatively normal ileofemoral arteries to allow the delivery and deployment of endovascular prosthesis. Endoluminal manipulation with passage of oversized endoluminal devices can lead to endothelial denudation, resulting in impaired cellular function. The purpose of this study was to assess the time course of endothelial function with vasoreactivity following oversized endovascular sheath insertion ranging from 1 day to 16 weeks in normal porcine iliac arteries. Following oversized introducer sheath placement in bilateral iliac arteries, vasoreactivity was tested using both endothelium-dependent and -independent vasodilators. Intravascular ultrasonography showed a significant reduction in the luminal area at 12 and 16 weeks. This was similarly supported by morphometric analysis, which showed increased medial thickness with an elevated intima to media ratio at the same time course. Endothelium-dependent relaxation to bradykinin, calcium ionophore A23187, serotonin, and adenosine diphosphate all uniformly displayed attenuated endothelial dysfunction at all time points when compared with the control group. In contrast, endothelium-independent relaxation showed a decreased vasoresponsiveness at 4 weeks. In conclusion, this study underscored the detrimental and chronic endothelial dysfunction in a normal artery caused by oversized introducer sheath placement. Chronically impaired endothelial function may play a role leading to iliofemoral artery thrombosis or late occlusion, which were well-recognized adverse events following endovascular aneurysm procedures. Our study underscores the importance of appropriate patient selection to minimize potential sheath oversize and endograft device miniaturization to avoid vessel wall injury and maintain vasoreactivity.

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Effects of in vivo administration of interleukin-2 (IL-2) and IL-4, alone and in combination, on ex vivo human basophil histamine release

Blood ◽

10.1182/blood.v79.6.1491.1491 ◽

1992 ◽

Vol 79 (6) ◽

pp. 1491-1495 ◽

Cited By ~ 8

Author(s):

MV White ◽

Y Igarashi ◽

BE Emery ◽

MT Lotze ◽

MA Kaliner

Keyword(s):

Histamine Release ◽

Ex Vivo ◽

Interleukin 2 ◽

Calcium Ionophore ◽

Calcium Ionophore A23187 ◽

Human Basophil ◽

Control Group ◽

Ionophore A23187 ◽

Ige Mediated

Abstract Human basophils possess receptors for interleukin-2 (IL-2) and IL-4. The effect of 3 days of intravenous administration of IL-2 and/or IL-4 on basophil histamine release was examined in three groups of patients receiving IL-2, IL-4, or the combination of agents as part of a protocol to treat malignant melanoma or renal cell carcinoma. Because all patients received ranitidine for control of side effects, a control group of patients receiving ranitidine for Zollinger-Ellison's syndrome was also studied. IL-4 significantly inhibited IgE-mediated histamine release, while there was a trend for enhancement of IgE-mediated histamine release by IL-2. Administration of the combination of IL-2 and IL-4 did not alter IgE-mediated basophil histamine release. Both IL- 2 and IL-4, alone and in combination, enhanced basophil histamine release induced by histamine releasing factors in human nasal washings. The effect of IL-2 alone was significantly greater than that of IL-4 alone or the combination of IL-2 plus IL-4. Taken together, the data suggest that when coadministered, IL-4 may inhibit the effects of IL-2 on basophils. Neither cytokine exerted any effect on basophil histamine release induced by the calcium ionophore A23187, nor did ranitidine cause any effects on histamine release induced by any of the stimulants. Thus, human basophil reactivity can be affected by IL-2 and by IL-4. The role that these two cytokines play in basophil function in vivo is likely to be complex.

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Effects of Sho-Saiko-To on Production of Prostaglandin E2 (PGE2), Leukotriene B4 (LTB4) and Superoxide from Peripheral Monocytes and Polymorphonuclear Cells Isolated from HIV Infected Individuals

The American Journal of Chinese Medicine ◽

10.1142/s0192415x96000025 ◽

1996 ◽

Vol 24 (01) ◽

pp. 1-10 ◽

Cited By ~ 6

Author(s):

Koji Miyamoto ◽

Michael Lange ◽

George McKinley ◽

Christine Stavropoulos ◽

Shin-ichi Moriya ◽

...

Keyword(s):

Chinese Medicine ◽

Immune Reaction ◽

Calcium Ionophore ◽

Leukotriene B4 ◽

Calcium Ionophore A23187 ◽

The Other ◽

Control Group ◽

Ionophore A23187 ◽

Polymorphonuclear Cells ◽

Healthy Control

The effects of Sho-saiko-to (SST), a traditional Chinese medicine, on the production of PGE2 from monocytes, LTB4 and superoxide from polymorphonuclear cells (PMNC) in HIY infected individuals were studied. SST inhibited the production of PGE2 from monocytes stimulated by opsonized zymosan in all groups including the healthy control group and also inhibited the production of superoxide from PMNC after stimulation with FMLP. On the other hand, SST enhanced the production of LTB4 when PMNC were stimulated by the calcium ionophore A23187. These results suggest that SST has different effects on the production of prostanoids or superoxide from monocytes and PMNC. Furthermore, our data indicates that inhibition of PGE2 or superoxide production will lead to indirect suppression of HIV, and enhancement of LTB4 will contribute to the upregulation of the immune reaction in my infected individuals.

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Characterization of the megakaryocyte secretory response: studies of continuously monitored release of endogenous ATP

Blood ◽

10.1182/blood.v61.5.967.bloodjournal615967 ◽

1983 ◽

Vol 61 (5) ◽

pp. 967-972

Author(s):

JL Miller

Keyword(s):

Guinea Pig ◽

Blood Platelets ◽

Atp Release ◽

Chemical Properties ◽

Calcium Ionophore ◽

Calcium Ionophore A23187 ◽

Ionophore A23187 ◽

Storage Pool ◽

Functional Aspects ◽

Absolute Requirement

Megakaryocytes share a number of structural and chemical properties with their progeny, blood platelets. With the availability of highly purified preparations of megakaryocytes isolated from guinea pig bone marrow, it is now also possible to study functional aspects of these cells. The present work reports the first study of the release of endogenously stored materials in megakaryocytes. Guinea pig megakaryocytes isolated to 75%-90% purity were exposed to thrombin or calcium ionophore (A23187) and the release of ATP was continuously monitored with the luciferin-luciferase reaction. Both maximal extent and initial rate of release were studied. Thrombin-induced release was half-maximal at thrombin concentrations of 0.2–0.5 NIH U/ml. At 4 U/ml thrombin, maximal release was 538 +/- 147 nmole ATP/10(9) megakaryocytes. A23187 induced half-maximal responses at concentrations of 7–8 microM. ATP release by ionophore showed a nearly absolute requirement for extracellular calcium, with release by thrombin showing only a partial calcium dependence. Following overnight culture, the response to thrombin was unchanged, whereas ATP release in response to ionophore was consistently increased (p less than 0.01). By comparison of maximally releasable ATP with total cellular ATP content, the storage pool of ATP in megakaryocytes was determined to comprise only 2%-6% of total megakaryocyte ATP, in contrast to an ATP storage pool of 20%-30% in guinea pig platelets. This difference may reflect further entry of ATP into the storage pool compartment or an enhanced ability of the cell to recognize and respond fully to platelet stimuli as the megakaryocyte reaches full maturity.

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Effects of in vivo administration of interleukin-2 (IL-2) and IL-4, alone and in combination, on ex vivo human basophil histamine release

Blood ◽

10.1182/blood.v79.6.1491.bloodjournal7961491 ◽

1992 ◽

Vol 79 (6) ◽

pp. 1491-1495

Author(s):

MV White ◽

Y Igarashi ◽

BE Emery ◽

MT Lotze ◽

MA Kaliner

Keyword(s):

Histamine Release ◽

Ex Vivo ◽

Interleukin 2 ◽

Calcium Ionophore ◽

Calcium Ionophore A23187 ◽

Human Basophil ◽

Control Group ◽

Ionophore A23187 ◽

Ige Mediated

Human basophils possess receptors for interleukin-2 (IL-2) and IL-4. The effect of 3 days of intravenous administration of IL-2 and/or IL-4 on basophil histamine release was examined in three groups of patients receiving IL-2, IL-4, or the combination of agents as part of a protocol to treat malignant melanoma or renal cell carcinoma. Because all patients received ranitidine for control of side effects, a control group of patients receiving ranitidine for Zollinger-Ellison's syndrome was also studied. IL-4 significantly inhibited IgE-mediated histamine release, while there was a trend for enhancement of IgE-mediated histamine release by IL-2. Administration of the combination of IL-2 and IL-4 did not alter IgE-mediated basophil histamine release. Both IL- 2 and IL-4, alone and in combination, enhanced basophil histamine release induced by histamine releasing factors in human nasal washings. The effect of IL-2 alone was significantly greater than that of IL-4 alone or the combination of IL-2 plus IL-4. Taken together, the data suggest that when coadministered, IL-4 may inhibit the effects of IL-2 on basophils. Neither cytokine exerted any effect on basophil histamine release induced by the calcium ionophore A23187, nor did ranitidine cause any effects on histamine release induced by any of the stimulants. Thus, human basophil reactivity can be affected by IL-2 and by IL-4. The role that these two cytokines play in basophil function in vivo is likely to be complex.

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Growth factors and the primary cilium in BALB/c 3T3 cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128432 ◽

1987 ◽

Vol 45 ◽

pp. 830-831

Author(s):

R. W. Tucker ◽

N. S. More ◽

S. Jayaraman

Keyword(s):

Growth Factors ◽

Primary Cilium ◽

Cultured Cells ◽

Morphological Changes ◽

Calcium Ionophore ◽

Growth Stimulation ◽

Calcium Ionophore A23187 ◽

Ionophore A23187 ◽

3T3 Cells ◽

Microtubule Depolymerization

The mechanisms by which polypeptide growth factors Induce DNA synthesis in cultured cells is not understood, but morphological changes Induced by growth factors have been used as clues to Intracellular messengers responsible for growth stimulation. One such morphological change has been the transient disappearance of the primary cilium, a “9 + 0” cilium formed by the perinuclear centriole in interphase cells. Since calcium ionophore A23187 also produced both mitogenesis and ciliary changes, microtubule depolymerization might explain ciliary disappearance monitored by indirect immunofluorescence with anti-tubulin antibody. However, complete resorption and subsequent reformation of the primary cilium occurs at mitosis, and might also account for ciliary disappearance induced by growth factors. To settle this issue, we investigated the ultrastructure of the primary cilium using serial thin-section electron microscopy of quiescent BALB/c 3T3 cells before and after stimulation with serum.

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Inhibition of Platelet Aggregation by Ethanol in Vitro Shows Specificity for Aggregating Agent Used and Is Influenced by Platelet Lipid Composition

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657214 ◽

1982 ◽

Vol 48 (01) ◽

pp. 049-053 ◽

Cited By ~ 47

Author(s):

C G Fenn ◽

J M Littleton

Keyword(s):

Platelet Aggregation ◽

Lipid Composition ◽

Saturated Fatty Acids ◽

Calcium Ionophore ◽

Cholesterol Content ◽

Membrane Lipid ◽

Calcium Ionophore A23187 ◽

Ionophore A23187 ◽

Increased Sensitivity

SummaryEthanol at physiologically tolerable concentrations inhibited platelet aggregation in vitro in a relatively specific way, which may be influenced by platelet membrane lipid composition. Aggregation to collagen, calcium ionophore A23187 and thrombin (low doses) were often markedly inhibited by ethanol, adrenaline and ADP responses were little affected, and aggregation to exogenous arachidonic acid was actually potentiated by ethanol. Aggregation to collagen, thrombin and A23187 was inhibited more by ethanol in platelets enriched with saturated fatty acids than in those enriched with unsaturated fats. Platelets enriched with cholesterol showed increased sensitivity to ADP, arachidonate and adrenaline but this increase in cholesterol content did not appear to influence the inhibition by ethanol of platelet responses. The results suggest that ethanol may inhibit aggregation by an effect on membrane fluidity and/or calcium mobilization resulting in decreased activity of a membrane-bound phospholipase.

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