Medicine and Health Sciences Commons^™

Parallel Changes In Intracellular Water Volume And Ph Induced By Nh3/Nh4+ Exposure In Single Neuroblastoma Cells, Victor M. Blanco, Martín S. Márquez, Francisco J. Alvarez-Leefmans

Pharmacology and Toxicology Faculty Publications

BACKGROUND:

Increased blood levels of ammonia (NH3) and ammonium (NH4(+)), i.e. hyperammonemia, leads to cellular brain edema in humans with acute liver failure. The pathophysiology of this edema is poorly understood. This is partly due to incomplete understanding of the osmotic effects of the pair NH3/NH4(+) at the cellular and molecular levels. Cell exposure to solutions containing NH3/NH4(+) elicits changes in intracellular pH (pHi), which can in turn affect cell water volume (CWV) by activating transport mechanisms that produce net gain or loss of solutes and water. The occurrence of CWV changes caused by NH3/NH4(+) has long been suspected, but …

Effects Of Endothelial Progenitor Cell-Derived Microvesicles On Hypoxia/Reoxygenation-Induced Endothelial Dysfunction And Apoptosis, Jinju Wang, Shuzhen Chen, Xioatang Ma, Chuanfang Cheng, Xiang Xiao, Ji Chen, Shiming Liu, Bin Zhao, Yanfang Chen

Pharmacology and Toxicology Faculty Publications

Oxidative stress-induced endothelial dysfunction plays a key role in ischemia/reperfusion injury. Recent evidence indicates that endothelial progenitor cell-derived microvesicles (EPC-MVs) can promote angiogenesis of endothelial cells (ECs). Here, we investigated the potential effects of EPC-MVs on hypoxia/reoxygenation (H/R) injury in human brain microvascular ECs (hb-ECs). MVs were prepared from EPCs cultured in a serum deprivation (SD) medium (starving stress, sEPC-MVs) or SD medium containing tumor necrosis factor-α (TNFα) (apoptotic stress, aEPC-MVs). H/R injury model of hb-ECs was produced by 6 hr hypoxia (1% O₂) and 24 hr reoxygenation. The H/R hb-ECs were co-cultured with EPC-MVs. Results showed that …

Human Endometrial Stromal Stem Cells Differentiate Into Megakaryocytes With The Ability To Produce Functional Platelets, Jinju Wang, Shuzhen Chen, Cheng Zhang, Samantha Stegeman, Teresa Pfaff-Amesse, Ying Zhang, Wenfeng Zhang, Lawrence Amesse, Yanfang Chen

Pharmacology and Toxicology Faculty Publications

Human endometrium is a high dynamic tissue that contains endometrial stromal stem cells (hESSCs). The hESSCs have been differentiated into a number of cell lineages. However, differentiation of hESSCs into megakaryocytes (MKs) has not yet been investigated. The aim of this study was to investigate the feasibility of MK generation from hESSCs and subsequent production of functional platelets (PLTs). In our study, hESSCs were cultured from endometrial stromal cells as confirmed by positive stromal cell specific markers (CD90 and CD29) and negative hematopoietic stem cell markers (CD45 and CD34) expression. Then, hESSCs were differentiated in a medium supplemented with thrombopoietin …

Effects Of Restricted Fructose Access On Body Weight And Blood Pressure Circadian Rhythms, Danielle Senador, Swapnil Vijay Shewale, Maria Claudia Irigoyen, Khalid M. Elased, Mariana Morris

Pharmacology and Toxicology Faculty Publications

High-fructose diet is known to produce cardiovascular and metabolic pathologies. The objective was to determine whether the timing of high fructose (10% liquid solution) intake affect the metabolic and cardiovascular outcomes. Male C57BL mice with radiotelemetric probes were divided into four groups: (1) 24 h water (control); (2) 24 h fructose (F24); (3) 12 h fructose during the light phase (F12L); (4) 12 h fructose during the dark phase (F12D). All fructose groups had higher fluid intake. Body weight was increased in mice on restricted access with no difference in total caloric intake. Fasting glycemia was higher in groups with …

Screening Assay For Enzymes Involved In Pathophysiology Using Seldi-Tof Mass Spectrometr, Khalid M. Elased, Mariana Morris

Pharmacology and Toxicology Faculty Publications

The invention provides methods for quantifying enzymatic activity of an enzyme with a known substrate. The methods employ SELDI-TOF mass spectrometry, and are suitable, in particular, for assaying aspects of the renin-angiotensin system. The methods may be utilized to assess and/or monitor biological conditions associated with the renin-angiotensin system prior to the manifestation of known physiological and biomarkers for such conditions. The methods are suitable for analysis of pharmacological effectors of the renin-angiotensin system, and are particularly suitable for automation and high-throughput screening assay design.

Screening Assay For Inhibitors Of Severe Acute Respiratory Syndrome (Sars) Using Seldi-Tof Mass Spectrometry, Khalid M. Elased, Mariana Morris

Pharmacology and Toxicology Faculty Publications

Mass spectrometric methods directed to screening libraries of compounds for agents that inhibit entry of Severe Acute Respiratory Syndrome (SARS) coronavirus (CoV) into cells are provided, along with methods for comparatively evaluating inhibitors of the SARS CoV.

Simultaneous Measurement Of Water Volume And Ph In Single Cells Using Bcecf And Fluorescence Imaging Microscopy, Francisco J. Alvarez-Leefmans, José J. Herrera-Pérez, Martín S. Márquez, Victor M. Blanco

Pharmacology and Toxicology Faculty Publications

Regulation and maintenance of cell water volume and intracellular pH (pH_i) are vital functions that are interdependent; cell volume regulation affects, and is in turn affected by, changes in pH_i. Disruption of either function underlies various pathologies. To study the interaction and kinetics of these two mechanisms, we developed and validated a quantitative fluorescence imaging microscopy method to measure simultaneous changes in pH_i and volume in single cells loaded with the fluorescent probe BCECF. CWV is measured at the excitation isosbestic wavelength, whereas pH_iis determined ratiometrically. The method has a time resolution of …

Phosphoglycan Messengers And Their Medical Uses (Sle), Khalid M. Elased, Khalid A. Gumaa, Hassan Rahmoune, Thomas Rademacher, J. B. De Souza

Pharmacology and Toxicology Faculty Publications

PPhosphoglycan messengers (PGMs) which are carbohydrate derivatised phosphatidyl cyclitols are disclosed, together with the finding that these substances are biologically active, especially in modulating plasma cholesterol, plasma triglycerides and/or high density lipoprotein levels and/or modulating the LDL:HDL ratio, and for the treatment of lipodystrophy or dyslipidemia. These compounds are distinct from GPI-anchors disclosed in the prior art as these GPI-anchors are protein linked and are not biologically active.

Phosphoglycan Messengers And Their Medical Uses (Lipidemia), Khalid M. Elased, Khalid A. Gumaa, Hassan Rahmoune, Thomas Rademacher

Pharmacology and Toxicology Faculty Publications

Phosphoglycan messengers (PGMs) which are carbohydrate derivatised phosphatidyl cyclitols are disclosed, together with the finding that these substances are biologically active, e.g. in lowering blood glucose levels. These compounds are distinct from GPI-anchors disclosed in the prior art as these GPI-anchors are protein linked and are not biologically active.

Treatment Of Diabetes, John H.L. Playfair, Khalid M. Elased, Joseph B. De Souza

Pharmacology and Toxicology Faculty Publications

The present invention provides methods for using a killed malaria parasite or an extract thereof in the treatment of non-insulin dependent diabetes mellitus (NIDDM).

Cation-Anion-Coupled Cotransport In An Immortalized Neuronal Cell Line (C6 Glioma), Kenneth B. E. Gagnon, Norma C. Adragna, Robert E.W. Fyffe, Peter K. Lauf

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Transient Nature Of The Stimulatory" Nem-Effect" On K-Cl Cotransport In Kccl-Transfected Hek293 And Primary Rat Aortic Smooth Muscle Cells, Peter K. Lauf, Jin Zhang, Jing Zhang, Norma C. Adragna

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Nh4+ Inhibits K-Cl Cotransport In Low K Sheep Red Blood Cells, Peter K. Lauf, Suhail Ahmed, Norma C. Adragna

Pharmacology and Toxicology Faculty Publications

No abstract provided.

K-Cl Cotransport: Membrane Immunofluorescence Localization By Confocal Microscopy Of The Kcc1 Protein, Before And After Truncation Of The Cooh-Terminal Domain, In Human Embryonic Kidney (Hek293) Cells, Peter K. Lauf, Kenneth B.E. Gagnon, Jin Zhang, Eric Delpire, Robert E.W. Fyffe, Norma C. Adragna

Pharmacology and Toxicology Faculty Publications

No abstract provided.

New Mechanism Of Regulation Of K+-Cl- Cotransport, Norma C. Adragna, H. Ahmed, C. M. Ferrell, J. Filosa, Peter K. Lauf

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Quantitative Analysis Of Changes In Cell Volume And Intracellular Ph Induced By Ammonia And Ammonium In Neuroblastoma Cells Studied With Fluorescent Probes, Vania D. Rosas, G. Boyarsky, S. Marquez, Francisco J. Alvarez-Leefmans

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Vasodilators Activate Erythrocyte K-Cl Cotransport, Norma C. Adragna, H. Ahmed, Peter K. Lauf

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Significance Of The Kccl Cytoplasmic Cooh-Terminal Fragment For The Ph Dependence Of K-Cl Cotransport In Transfected Human Embryonic Kidney Cells, Norma C. Adragna, Jin Zhang, Peter K. Lauf

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Proton (H) Modulation Of K-Cl Cotransport Through Both Internal And External Sites In Dids-Ph-Clamped Low Magnesium Lk Sheep Erythrocytes, Peter K. Lauf, Norma C. Adragna

Pharmacology and Toxicology Faculty Publications

No abstract provided.

A Thermodynamic Study Of Electroneutral K-Cl Cotransport In Ph- And Volume-Clamped Low K Sheep Erythrocytes With Normal And Low Internal Magnesium, Peter K. Lauf, Norma C. Adragna

Pharmacology and Toxicology Faculty Publications

Swelling-Induced human erythrocyte K-Cl cotransport is membrane potential independent and capable of uphill transport. However, a complete thermodynamic analysis of basal and stimulated K-Cl cotransport, at constant cell volume, is missing, This study was performed in low K sheep red blood cells before and after reducing cellular free Mg into the nanomolar range with the divalent cation ionophore A23187 and a chelator, an intervention known to stimulate K-Cl cotransport. The anion exchange inhibitor 4,4'diisothiocyanato-2,2'disulfonic stilbene was used to clamp intracellular pH and Cl or NO3 concentrations. Cell volume was maintained constant as external and internal pH differed by more than …

Sidedness Of H+ Action On K-Cl Cotransport In Dids Ph(I)-Clamped Low K Sheep Red Blood Cells With Reduced Mg(I), Peter K. Lauf, Norma C. Adragna

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Dependence Of Thiol-Stimulated K-Cl Cotransport On Redox State Of Low K Sheep Red Blood Cells, Peter K. Lauf, Norma C. Adragna, Nihal S. Agar

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Hypoglycemia And Hyperinsulinemia In Rodent Models Of Severe Malaria Infection, Khalid M. Elased, J. H. L. Playfair

Pharmacology and Toxicology Faculty Publications

Severe hypoglycemia developed during nonlethal Plasmodium chabaudi and lethal P. yoelii blood stage malaria infection in mice, always in association with hyperinsulinemia. Supernatants of lethal P. yoelii incubated overnight induced hypoglycemia and hyperinsulinemia in normal mice. In murine malaria, hypoglycemia may be largely secondary to increased insulin secretion.

Quinine And Quinidine Inhibit K-Cl Cotransport In Low K Sheep Erythrocytes, Norma C. Adragna, Peter K. Lauf

Pharmacology and Toxicology Faculty Publications

No abstract provided.

N-Ethylmaleimide Treatment Of Low K Sheep Red-Blood-Cells At Different Temperatures Reveals Role Of Thiols And Mg For Activation And Inactivation Of K-Cl Cotransport, Peter K. Lauf, R. Moezzi, Norma C. Adragna

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Sodium Pump And Leaks In Cultured Vascular Endothelial Cells, Norma C. Adragna

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Passive Cation Transport In Reversibly Sickling Deer Red Blood Cells, Norma C. Adragna, Peter K. Lauf

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Kinetics Of Na/Li Exchange In High-K (Hk) And Low-K (Lk) Sheep Red Cells (Src), K. H. Ryu, Norma C. Adragna, D. Bradley, Peter K. Lauf

Pharmacology and Toxicology Faculty Publications

No abstract provided.

Optimal Isolation Conditions For Ion-Transport Studies In Pig Aortic Endothelial-Cells, Norma C. Adragna

Pharmacology and Toxicology Faculty Publications

No abstract provided.