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Jiang D, Houck KL, Murdiyarso L, Higgins H, Rhoads N, Romero SK, Kozar R, Nascimbene A, Gernsheimer TB, Sanchez ZAC, Ramasubramanian AK, Adili R, Dong JF. RBCs regulate platelet function and hemostasis under shear conditions through biophysical and biochemical means. Blood 2024; 144:1521-1531. [PMID: 38985835 DOI: 10.1182/blood.2024023887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 05/28/2024] [Accepted: 07/03/2024] [Indexed: 07/12/2024] Open
Abstract
ABSTRACT Red blood cells (RBCs) have been hypothesized to support hemostasis by facilitating platelet margination and releasing platelet-activating factors such as adenosine 5'-diphosphate (ADP). Significant knowledge gaps remain regarding how RBCs influence platelet function, especially in (patho)physiologically relevant hemodynamic conditions. Here, we present results showing how RBCs affect platelet function and hemostasis in conditions of anemia, thrombocytopenia, and pancytopenia and how the biochemical and biophysical properties of RBCs regulate platelet function at the blood and vessel wall interface and in the fluid phase under flow conditions. We found that RBCs promoted platelet deposition to collagen under flow conditions in moderate (50 × 103/μL) but not severe (10 × 103/μL) thrombocytopenia in vitro. Reduction in hematocrit by 45% increased bleeding in mice with hemolytic anemia. In contrast, bleeding diathesis was observed in mice with a 90% but not with a 60% reduction in platelet counts. RBC transfusion improved hemostasis by enhancing fibrin clot formation at the site of vascular injury in mice with severe pancytopenia induced by total body irradiation. Altering membrane deformability changed the ability of RBCs to promote shear-induced platelet aggregation. RBC-derived ADP contributed to platelet activation and aggregation in vitro under pathologically high shear stresses, as observed in patients supported by left ventricular assist devices. These findings demonstrate that RBCs support platelet function and hemostasis through multiple mechanisms, both at the blood and vessel wall interface and in the fluidic phase of circulation.
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Affiliation(s)
- Debbie Jiang
- Division of Hematology and Oncology, University of Washington, Seattle, WA
- Fred Hutchinson Cancer Center, Seattle, WA
- Division of Hematology, Massachusetts General Hospital, Harvard Medical School, Boston, MA
| | | | | | | | | | | | - Rosemary Kozar
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD
| | - Angelo Nascimbene
- Center for Advanced Cardiopulmonary Therapies and Transplantation, The University of Texas Houston Health Science Center, Houston, TX
| | - Terry B Gernsheimer
- Division of Hematology and Oncology, University of Washington, Seattle, WA
- Fred Hutchinson Cancer Center, Seattle, WA
| | - Zyrina Alura C Sanchez
- Department of Chemical and Materials Engineering, San Jose State University, San Jose, CA
| | | | | | - Jing-Fei Dong
- Division of Hematology and Oncology, University of Washington, Seattle, WA
- Bloodworks Research Institute, Seattle, WA
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Korf EA, Novozhilov AV, Mindukshev IV, Glotov AS, Kudryavtsev IV, Baidyuk EV, Dobrylko IA, Voitenko NG, Voronina PA, Habeeb S, Ghanem A, Osinovskaya NS, Serebryakova MK, Krivorotov DV, Jenkins RO, Goncharov NV. Testing Green Tea Extract and Ammonium Salts as Stimulants of Physical Performance in a Forced Swimming Rat Experimental Model. Int J Mol Sci 2024; 25:10438. [PMID: 39408765 PMCID: PMC11477139 DOI: 10.3390/ijms251910438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2024] [Revised: 09/23/2024] [Accepted: 09/24/2024] [Indexed: 10/20/2024] Open
Abstract
The study of drugs of natural origin that increase endurance and/or accelerate recovery is an integral part of sports medicine and physiology. In this paper, decaffeinated green tea extract (GTE) and two ammonium salts-chloride (ACL) and carbonate (ACR)-were tested individually and in combination with GTE as stimulants of physical performance in a forced swimming rat experimental model. The determined parameters can be divided into seven blocks: functional (swimming duration); biochemistry of blood plasma; biochemistry of erythrocytes; hematology; immunology; gene expression of slow- and fast-twitch muscles (m. soleus, SOL, and m. extensor digitorum longus, EDL, respectively); and morphometric indicators of slow- and fast-twitch muscles. Regarding the negative control (intact animals), the maximum number of changes in all blocks of indicators was recorded in the GTE + ACR group, whose animals showed the maximum functional result and minimum lactate values on the last day of the experiment. Next, in terms of the number of changes, were the groups ACR, ACL, GTE + ACL, GTE and NaCl (positive control). In general, the number of identified adaptive changes was proportional to the functional state of the animals of the corresponding groups, in terms of the duration of the swimming load in the last four days of the experiment. However, not only the total number but also the qualitative composition of the identified changes is of interest. The results of a comparative analysis suggest that, in the model of forced swimming we developed, GTE promotes restoration of the body and moderate mobilization of the immune system, while small doses of ammonium salts, especially ammonium carbonate, contribute to an increase in physical performance, which is associated with satisfactory restoration of skeletal muscles and the entire body. The combined use of GTE with ammonium salts does not give a clearly positive effect.
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Affiliation(s)
- Ekaterina A. Korf
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia
| | - Artem V. Novozhilov
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia
| | - Igor V. Mindukshev
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia
| | - Andrey S. Glotov
- D.O. Ott Research Institute of Obstetrics, Gynecology and Reproductology, St. Petersburg 199034, Russia
| | | | - Ekaterina V. Baidyuk
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia
| | - Irina A. Dobrylko
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia
| | - Natalia G. Voitenko
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia
| | - Polina A. Voronina
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia
| | - Samarmar Habeeb
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia
| | - Afrah Ghanem
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia
| | - Natalia S. Osinovskaya
- D.O. Ott Research Institute of Obstetrics, Gynecology and Reproductology, St. Petersburg 199034, Russia
| | | | - Denis V. Krivorotov
- Research Institute of Hygiene, Occupational Pathology and Human Ecology of the Federal Medical Biological Agency, p.o. Kuz’molovsky bld.93, St. Petersburg 188663, Russia
| | - Richard O. Jenkins
- Leicester School of Allied Health Sciences, De Montfort University, The Gateway, Leicester LE1 9BH, UK
| | - Nikolay V. Goncharov
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, pr. Torez 44, St. Petersburg 194223, Russia
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Ji D, Peng Y, Zhang Y, Tang X, Zhao M, Ran L, Wu X, Luo X, Chen S, Jiang T, Li J, Yang Z, Liu Y. Recent advances and clinical applications of red blood cell lifespan measurement. Heliyon 2024; 10:e36507. [PMID: 39281613 PMCID: PMC11401096 DOI: 10.1016/j.heliyon.2024.e36507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2024] [Revised: 08/16/2024] [Accepted: 08/16/2024] [Indexed: 09/18/2024] Open
Abstract
The red blood cell (RBC) lifespan is a crucial indicator used in clinical diagnostics, treatment, and disease monitoring. This biomarker quantifies the duration that red blood cells (RBCs) circulate within the bloodstream after being released from the bone marrow, serving as a sensitive and direct indicator of red blood cell turnover. Conventional techniques for RBC lifespan measurement, including differential agglutination, 51Cr labeling, and 15N glycine labeling, each present their own set of challenges, such as complexity, radioactive exposure, and potential allergic reaction. The carbon monoxide (CO) breath test has emerged as an advanced and non-invasive alternative, indirectly assessing RBC lifespan through hemoglobin (Hb) renewal rates. This method is convenient, rapid, and lacks the drawbacks of traditional approaches. The CO breath test for RBC lifespan is widely utilized in benign anemia, malignant hematological disorders, neonatal hyperbilirubinemia, and diabetes mellitus, offering valuable insights into disease mechanisms, progression, and treatment outcomes.
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Affiliation(s)
- Dan Ji
- School of Medicine, Chongqing University, Chongqing, 400030, China
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Yu Peng
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Yakun Zhang
- School of Medicine, Chongqing University, Chongqing, 400030, China
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Xinyi Tang
- School of Medicine, Chongqing University, Chongqing, 400030, China
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Mingyu Zhao
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Longrong Ran
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Xuelian Wu
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Xin Luo
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Shuang Chen
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Tingting Jiang
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Jun Li
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Zailin Yang
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
| | - Yao Liu
- Department of Hematology-Oncology, Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030, China
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Di Poto C, Tian X, Mellors S, Rosengren S, Issop S, Bonvini SJ, Hess S, Allman EL. A microfluidic chip-based capillary zone electrophoresis-mass spectrometry method for measuring adenosine 5'-Triphosphate and its similar nucleotide analogues. Anal Chim Acta 2024; 1298:342400. [PMID: 38462348 DOI: 10.1016/j.aca.2024.342400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 02/16/2024] [Accepted: 02/20/2024] [Indexed: 03/12/2024]
Abstract
BACKGROUND Extracellular ATP is involved in disorders that cause inflammation of the airways and cough, thus limiting its release has therapeutic benefits. Standard luminescence-based ATP assays measure levels indirectly through enzyme degradation and do not provide a simultaneous readout for other nucleotide analogues. Conversely, mass spectrometry can provide direct ATP measurements, however, common RPLC and HILIC methods face issues because these molecules are unstable, metal-sensitive analytes which are often poorly retained. These difficulties have traditionally been overcome using passivation or ion-pairing chromatography, but these approaches can be problematic for LC systems. As a result, more effective analytical methods are needed. RESULTS Here, we introduce a new application that uses microfluidic chip-based capillary zone electrophoresis-mass spectrometry (μCZE-MS) to measure ATP and its analogues simultaneously in biofluids. The commercially available ZipChip Interface and a High-Resolution Bare-glass microchip (ZipChip, HRB, 908 Devices Inc.) coupled to a Thermo Scientific Tribrid Orbitrap, were successfully used to separate and detect various nucleotide standards, as well as ATP, ADP, AMP, and adenosine in plasma and BALF obtained from naïve Brown Norway rats. The findings demonstrate that this approach can rapidly and directly detect ATP and its related nucleotide analogues, while also highlighting the need to preserve these molecules in biofluids with chelators like EDTA. In addition, we demonstrate that this μCZE-MS method is also suitable for detecting a variety of metabolites, revealing additional potential future applications. SIGNIFICANCE This innovative μCZE-MS approach provides a robust new tool to directly measure ATP and other nucleotide analogues in biofluids. This can enable the study of eATP in human disease and potentially contribute to the creation of ATP-targeting therapies for airway illnesses.
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Affiliation(s)
- Cristina Di Poto
- Dynamic Omics, Centre for Genomics Research, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD, 20878, USA
| | - Xiang Tian
- Dynamic Omics, Centre for Genomics Research, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD, 20878, USA
| | | | - Sanna Rosengren
- Translational Science and Experimental Medicine, Respiratory & Immunology, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Sabina Issop
- Division of Airway Disease, Respiratory Pharmacology Group, NHLI, Imperial College London, London, SW7 2AZ, UK
| | - Sara J Bonvini
- In Vivo Bioscience, Research and Early Development, Respiratory & Immunology, BioPharmaceuticals R&D, AstraZeneca, London, SW7 2AZ, UK
| | - Sonja Hess
- Dynamic Omics, Centre for Genomics Research, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD, 20878, USA
| | - Erik L Allman
- Dynamic Omics, Centre for Genomics Research, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD, 20878, USA.
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Pettersen JS, Høg FF, Nielsen FD, Møller-Jensen J, Jørgensen MG. Global transcriptional responses of pneumococcus to human blood components and cerebrospinal fluid. Front Microbiol 2022; 13:1060583. [PMID: 36620004 PMCID: PMC9812572 DOI: 10.3389/fmicb.2022.1060583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 11/22/2022] [Indexed: 12/24/2022] Open
Abstract
Streptococcus pneumoniae (pneumococcus) is a leading cause of severe invasive infectious diseases such as sepsis and meningitis. Understanding how pneumococcus adapts and survive in the human bloodstream environment and cerebrospinal fluid (CSF) is important for development of future treatment strategies. This study investigates the global transcriptional response of pneumococcus to human blood components and CSF acquired from discarded and anonymized patient samples. Extensive transcriptional changes to human blood components were observed during early stages of interaction. Plasma-specific responses were primarily related to metabolic components and include strong downregulation of fatty acid biosynthesis genes, and upregulation of nucleotide biosynthesis genes. No transcriptional responses specific to the active plasma proteins (e.g., complement proteins) were observed during early stages of interaction as demonstrated by a differential expression analysis between plasma and heat-inactivated plasma. The red blood cell (RBC)-specific response was far more complex, and included activation of the competence system, differential expression of several two-component systems, phosphotransferase systems and transition metal transporter genes. Interestingly, most of the changes observed for CSF were also observed for plasma. One of the few CSF-specific responses, not observed for plasma, was a strong downregulation of the iron acquisition system piuBCDA. Intriguingly, this transcriptomic analysis also uncovers significant differential expression of more than 20 small non-coding RNAs, most of them in response to RBCs, including small RNAs from uncharacterized type I toxin-antitoxin systems. In summary, this transcriptomic study identifies key pneumococcal metabolic pathways and regulatory genes involved with adaptation to human blood and CSF. Future studies should uncover the potential involvement of these factors with virulence in-vivo.
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The role of SH groups in the regulation of Gardos channels in glucose deficiency. ACTA BIOMEDICA SCIENTIFICA 2022. [DOI: 10.29413/abs.2022-7.5-1.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Background. Disruption of the energy balance of erythrocytes under conditions of a decrease in the glycolysis level can cause a change in the ion permeability of their membrane. The aim. To study Ca2+-dependent potassium permeability of the erythrocytes membrane in the presence of SH group modifiers under conditions of glucose deficiency. Materials and methods. The study used precipitated erythrocytes obtained from the blood of 20 male Wistar rats. The change in the Ca2+-dependent potassium conductivity of the erythrocyte membrane was determined using the potentiometric method. The A23187-and redox-induced hyperpolarization responses of erythrocytes were evaluated. Results. Glucose deficiency in the medium, as well as the use of the glycolysis inhibitor 2-deoxyglucose, led to an increase in the amplitude of A23187-stimulated membrane hyperpolarization by the opening of the Gardos channels. At the same time, the redox-dependent hyperpolarization of the erythrocyte membrane turned out to be insensitive to a decrease in the glucose content in the medium and to the glycolysis inhibition. The effects of SH group modifiers in the normal incubation medium and under glucose deficiency turned out to be multidirectional and depended on the method of stimulation of Gardos channels. Conclusion. The results obtained indicate that metabolic disorders in erythrocytes under conditions of glucose deficiency lead to a change in the mechanisms of control of Gardos channels with the participation of SH groups of the proteins of these channels or their regulatory proteins.
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Guo S, Han F, Zhu W. CD39 - A bright target for cancer immunotherapy. Biomed Pharmacother 2022; 151:113066. [PMID: 35550530 DOI: 10.1016/j.biopha.2022.113066] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Revised: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 11/27/2022] Open
Abstract
The ATP-adenosine pathway functions as a key modulator of innate and adaptive immunity within the tumor microenvironment, and cancer immune evasion largely involves the generation of high amounts of immunosuppressive extracellular adenosine (eADO). Consequently, inhibition of eADO-generating enzymes and/or eADO receptors can effectively restore the antitumor immunity of multiple immune cells. With several clinical strategies currently being explored to modulating the eADO pathway in patients with cancer, recent clinical data with antagonists targeting CD73 and A2A receptor have demonstrated a promising therapeutic potential in cancer. Recent findings reveal that the ectonucleotidase CD39, the limiting enzyme been viewed as "immunological switch", converts ATP-driven pro-inflammatory milieu to an anti-inflammatory state mediated by adenosine. Owing to its superior feature of CD39 antagonism that rely not only on preventing the accumulation of adenosine but also on the stabilization of extracellular ATP to restore antitumor immunity, several inhibitors and clinical trials based on CD39 are being evaluated. Consequently, there is currently a focus on understanding the role of CD39 in governing immunity and how therapeutic strategies targeting this pathway alter the antitumor potential. We herein review the impact of CD39 on tumor microenvironment with a focus on treatment preference. Additionally, we also discuss the implication for rational combination therapies, molecular regulation, as well as potential limitations.
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Affiliation(s)
- Shuwei Guo
- School of Medicine, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Fengfeng Han
- School of Medicine, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Wei Zhu
- School of Medicine, Jiangsu University, Zhenjiang, Jiangsu, China.
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Purinergic signaling is essential for full Psickle activation by hypoxia and by normoxic acid pH in mature human sickle red cells and in vitro-differentiated cultured human sickle reticulocytes. Pflugers Arch 2022; 474:553-565. [PMID: 35169901 DOI: 10.1007/s00424-022-02665-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 12/03/2021] [Accepted: 01/11/2022] [Indexed: 10/19/2022]
Abstract
Paracrine ATP release by erythrocytes has been shown to regulate endothelial cell function via purinergic signaling, and this erythoid-endothelial signaling network is pathologically dysregulated in sickle cell disease. We tested the role of extracellular ATP-mediated purinergic signaling in the activation of Psickle, the mechanosensitive Ca2+-permeable cation channel of human sickle erythrocytes (SS RBC). Psickle activation increases intracellular [Ca2+] to stimulate activity of the RBC Gardos channel, KCNN4/KCa3.1, leading to cell shrinkage and accelerated deoxygenation-activated sickling.We found that hypoxic activation of Psickle recorded by cell-attached patch clamp in SS RBC is inhibited by extracellular apyrase, which hydrolyzes extracellular ATP. Hypoxic activation of Psickle was also inhibited by the pannexin-1 inhibitor, probenecid, and by the P2 antagonist, suramin. A Psickle-like activity was also activated in normoxic SS RBC (but not in control red cells) by bath pH 6.0. Acid-activated Psickle-like activity was similarly blocked by apyrase, probenecid, and suramin, as well as by the Psickle inhibitor, Grammastola spatulata mechanotoxin-4 (GsMTx-4).In vitro-differentiated cultured human sickle reticulocytes (SS cRBC), but not control cultured reticulocytes, also exhibited hypoxia-activated Psickle activity that was abrogated by GsMTx-4. Psickle-like activity in SS cRBC was similarly elicited by normoxic exposure to acid pH, and this acid-stimulated activity was nearly completely blocked by apyrase, probenecid, and suramin, as well as by GsMTx-4.Thus, hypoxia-activated and normoxic acid-activated cation channel activities are expressed in both SS RBC and SS cRBC, and both types of activation appear to be mediated or greatly amplified by autocrine or paracrine purinergic signaling.
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