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Guo Z, Sun S, Xiao S, Chen G, Chen P, Yang Z, Tang X, Huang L, Wang Y. COVID-19 is associated with changes in brain function and structure: A multimodal meta-analysis of neuroimaging studies. Neurosci Biobehav Rev 2024; 164:105792. [PMID: 38969310 DOI: 10.1016/j.neubiorev.2024.105792] [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: 01/29/2024] [Revised: 04/23/2024] [Accepted: 06/27/2024] [Indexed: 07/07/2024]
Abstract
The actual role of coronavirus disease 2019 (COVID-19) in brain damage has been increasingly reported, necessitating a meta-analysis to collate and summarize the inconsistent findings from functional imaging and voxel-based morphometry (VBM) studies. A comprehensive voxel-wise meta-analysis of the whole brain was conducted to identify alterations in functional activity and gray matter volume (GMV) between COVID-19 patients and healthy controls (HCs) by using Seed-based d Mapping software. We included 15 functional imaging studies (484 patients with COVID-19, 534 HCs) and 9 VBM studies (449 patients with COVID-19, 388 HCs) in the analysis. Overall, patients with COVID-19 exhibited decreased functional activity in the right superior temporal gyrus (STG) (extending to the right middle and inferior temporal gyrus, insula, and temporal pole [TP]), left insula, right orbitofrontal cortex (OFC) (extending to the right olfactory cortex), and left cerebellum compared to HCs. For VBM, patients with COVID-19, relative to HCs, showed decreased GMV in the bilateral anterior cingulate cortex/medial prefrontal cortex (extending to the bilateral OFC), and left cerebellum, and increased GMV in the bilateral amygdala (extending to the bilateral hippocampus, STG, TP, MTG, and right striatum). Moreover, overlapping analysis revealed that patients with COVID-19 exhibited both decreased functional activity and increased GMV in the right TP (extending to the right STG). The multimodal meta-analysis suggests that brain changes of function and structure in the temporal lobe, OFC and cerebellum, and functional or structural alterations in the insula and the limbic system in COVID-19. These findings contribute to a better understanding of the pathophysiology of brain alterations in COVID-19. SIGNIFICANCE STATEMENT: This first large-scale multimodal meta-analysis collates existing neuroimaging studies and provides voxel-wise functional and structural whole-brain abnormalities in COVID-19. Findings of this meta-analysis provide valuable insights into the dynamic brain changes (from infection to recovery) and offer further explanations for the pathophysiological basis of brain alterations in COVID-19.
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Affiliation(s)
- Zixuan Guo
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China; Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Shilin Sun
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China; Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Shu Xiao
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China; Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Guanmao Chen
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China; Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Pan Chen
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China; Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Zibin Yang
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China; Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Xinyue Tang
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China; Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Li Huang
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China; Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Ying Wang
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China; Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China.
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Scarpellino G, Brunetti V, Berra-Romani R, De Sarro G, Guerra G, Soda T, Moccia F. The Unexpected Role of the Endothelial Nitric Oxide Synthase at the Neurovascular Unit: Beyond the Regulation of Cerebral Blood Flow. Int J Mol Sci 2024; 25:9071. [PMID: 39201757 PMCID: PMC11354477 DOI: 10.3390/ijms25169071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2024] [Revised: 08/19/2024] [Accepted: 08/21/2024] [Indexed: 09/03/2024] Open
Abstract
Nitric oxide (NO) is a highly versatile gasotransmitter that has first been shown to regulate cardiovascular function and then to exert tight control over a much broader range of processes, including neurotransmitter release, neuronal excitability, and synaptic plasticity. Endothelial NO synthase (eNOS) is usually far from the mind of synaptic neurophysiologists, who have focused most of their attention on neuronal NO synthase (nNOS) as the primary source of NO at the neurovascular unit (NVU). Nevertheless, the available evidence suggests that eNOS could also contribute to generating the burst of NO that, serving as volume intercellular messenger, is produced in response to neuronal activity in the brain parenchyma. Herein, we review the role of eNOS in both the regulation of cerebral blood flow and of synaptic plasticity and discuss the mechanisms by which cerebrovascular endothelial cells may transduce synaptic inputs into a NO signal. We further suggest that eNOS could play a critical role in vascular-to-neuronal communication by integrating signals converging onto cerebrovascular endothelial cells from both the streaming blood and active neurons.
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Affiliation(s)
- Giorgia Scarpellino
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (G.S.); (V.B.)
| | - Valentina Brunetti
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, 27100 Pavia, Italy; (G.S.); (V.B.)
| | - Roberto Berra-Romani
- Department of Biomedicine, School of Medicine, Benemérita Universidad Autónoma de Puebla, Puebla 72410, Mexico;
| | - Giovambattista De Sarro
- Department of Health Sciences, University of Magna Graecia, 88100 Catanzaro, Italy; (G.D.S.); (T.S.)
| | - Germano Guerra
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, 86100 Campobasso, Italy;
| | - Teresa Soda
- Department of Health Sciences, University of Magna Graecia, 88100 Catanzaro, Italy; (G.D.S.); (T.S.)
| | - Francesco Moccia
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, 86100 Campobasso, Italy;
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Yadav S, Deepika, Moar K, Kumar A, Khola N, Pant A, Kakde GS, Maurya PK. Reconsidering red blood cells as the diagnostic potential for neurodegenerative disorders. Biol Cell 2024; 116:e2400019. [PMID: 38822416 DOI: 10.1111/boc.202400019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Revised: 04/12/2024] [Accepted: 04/29/2024] [Indexed: 06/03/2024]
Abstract
BACKGROUND Red blood cells (RBCs) are usually considered simple cells and transporters of gases to tissues. HYPOTHESIS However, recent research has suggested that RBCs may have diagnostic potential in major neurodegenerative disorders (NDDs). RESULTS This review summarizes the current knowledge on changes in RBC in Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and other NDDs. It discusses the deposition of neuronal proteins like amyloid-β, tau, and α-synuclein, polyamines, changes in the proteins of RBCs like band-3, membrane transporter proteins, heat shock proteins, oxidative stress biomarkers, and altered metabolic pathways in RBCs during neurodegeneration. It also highlights the comparison of RBC diagnostic markers to other in-market diagnoses and discusses the challenges in utilizing RBCs as diagnostic tools, such as the need for standardized protocols and further validation studies. SIGNIFICANCE STATEMENT The evidence suggests that RBCs have diagnostic potential in neurodegenerative disorders, and this study can pave the foundation for further research which may lead to the development of novel diagnostic approaches and treatments.
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Affiliation(s)
- Somu Yadav
- Department of Biochemistry, Central University of Haryana, Mahendergarh, India
| | - Deepika
- Department of Biochemistry, Central University of Haryana, Mahendergarh, India
| | - Kareena Moar
- Department of Biochemistry, Central University of Haryana, Mahendergarh, India
| | - Akshay Kumar
- Department of Biochemistry, Central University of Haryana, Mahendergarh, India
| | - Nikhila Khola
- Department of Biochemistry, Central University of Haryana, Mahendergarh, India
| | - Anuja Pant
- Department of Biochemistry, Central University of Haryana, Mahendergarh, India
| | - Ganseh S Kakde
- Department of Biochemistry, Central University of Haryana, Mahendergarh, India
| | - Pawan Kumar Maurya
- Department of Biochemistry, Central University of Haryana, Mahendergarh, India
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Jin X, Zhang Y, Wang D, Zhang X, Li Y, Wang D, Liang Y, Wang J, Zheng L, Song H, Zhu X, Liang J, Ma J, Gao J, Tong J, Shi L. Metabolite and protein shifts in mature erythrocyte under hypoxia. iScience 2024; 27:109315. [PMID: 38487547 PMCID: PMC10937114 DOI: 10.1016/j.isci.2024.109315] [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] [Indexed: 03/17/2024] Open
Abstract
As the only cell type responsible for oxygen delivery, erythrocytes play a crucial role in supplying oxygen to hypoxic tissues, ensuring their normal functions. Hypoxia commonly occurs under physiological or pathological conditions, and understanding how erythrocytes adapt to hypoxia is fundamental for exploring the mechanisms of hypoxic diseases. Additionally, investigating acute and chronic mountain sickness caused by plateaus, which are naturally hypoxic environments, will aid in the study of hypoxic diseases. In recent years, increasingly developed proteomics and metabolomics technologies have become powerful tools for studying mature enucleated erythrocytes, which has significantly contributed to clarifying how hypoxia affects erythrocytes. The aim of this article is to summarize the composition of the cytoskeleton and cytoplasmic proteins of hypoxia-altered erythrocytes and explore the impact of hypoxia on their essential functions. Furthermore, we discuss the role of microRNAs in the adaptation of erythrocytes to hypoxia, providing new perspectives on hypoxia-related diseases.
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Affiliation(s)
- Xu Jin
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Yingnan Zhang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Ding Wang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Xiaoru Zhang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Yue Li
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Di Wang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Yipeng Liang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Jingwei Wang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Lingyue Zheng
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Haoze Song
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Xu Zhu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Jing Liang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Jinfa Ma
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Jie Gao
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Jingyuan Tong
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
| | - Lihong Shi
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
- Tianjin Institutes of Health Science, Tianjin 301600, China
- CAMS Center for Stem Cell Medicine, PUMC Department of Stem Cell and Regenerative Medicine, Tianjin 300020, China
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Guo Z, Tang X, Xiao S, Yan H, Sun S, Yang Z, Huang L, Chen Z, Wang Y. Systematic review and meta-analysis: multimodal functional and anatomical neural alterations in autism spectrum disorder. Mol Autism 2024; 15:16. [PMID: 38576034 PMCID: PMC10996269 DOI: 10.1186/s13229-024-00593-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 03/13/2024] [Indexed: 04/06/2024] Open
Abstract
BACKGROUND This meta-analysis aimed to explore the most robust findings across numerous existing resting-state functional imaging and voxel-based morphometry (VBM) studies on the functional and structural brain alterations in individuals with autism spectrum disorder (ASD). METHODS A whole-brain voxel-wise meta-analysis was conducted to compare the differences in the intrinsic functional activity and gray matter volume (GMV) between individuals with ASD and typically developing individuals (TDs) using Seed-based d Mapping software. RESULTS A total of 23 functional imaging studies (786 ASD, 710 TDs) and 52 VBM studies (1728 ASD, 1747 TDs) were included. Compared with TDs, individuals with ASD displayed resting-state functional decreases in the left insula (extending to left superior temporal gyrus [STG]), bilateral anterior cingulate cortex/medial prefrontal cortex (ACC/mPFC), left angular gyrus and right inferior temporal gyrus, as well as increases in the right supplementary motor area and precuneus. For VBM meta-analysis, individuals with ASD displayed decreased GMV in the ACC/mPFC and left cerebellum, and increased GMV in the left middle temporal gyrus (extending to the left insula and STG), bilateral olfactory cortex, and right precentral gyrus. Further, individuals with ASD displayed decreased resting-state functional activity and increased GMV in the left insula after overlapping the functional and structural differences. CONCLUSIONS The present multimodal meta-analysis demonstrated that ASD exhibited similar alterations in both function and structure of the insula and ACC/mPFC, and functional or structural alterations in the default mode network (DMN), primary motor and sensory regions. These findings contribute to further understanding of the pathophysiology of ASD.
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Affiliation(s)
- Zixuan Guo
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Xinyue Tang
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Shu Xiao
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Hong Yan
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Shilin Sun
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Zibin Yang
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Li Huang
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Zhuoming Chen
- Department of Rehabilitation Medicine, The First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, China
| | - Ying Wang
- Medical Imaging Center, The First Affiliated Hospital of Jinan University, Guangzhou, China.
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Yan H, Xiao S, Fu S, Gong J, Qi Z, Chen G, Chen P, Tang G, Su T, Yang Z, Wang Y. Functional and structural brain abnormalities in substance use disorder: A multimodal meta-analysis of neuroimaging studies. Acta Psychiatr Scand 2023; 147:345-359. [PMID: 36807120 DOI: 10.1111/acps.13539] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 01/19/2023] [Accepted: 02/12/2023] [Indexed: 02/23/2023]
Abstract
INTRODUCTION Numerous neuroimaging studies of resting-state functional imaging and voxel-based morphometry (VBM) have revealed that patients with substance use disorder (SUD) may present brain abnormalities, but their results were inconsistent. This multimodal neuroimaging meta-analysis aimed to estimate common and specific alterations in SUD patients by combining information from all available studies of spontaneous functional activity and gray matter volume (GMV). METHODS A whole-brain meta-analysis on resting-state functional imaging and VBM studies was conducted using the Seed-based d Mapping with Permutation of Subject Images (SDM-PSI) software, followed by multimodal overlapping to comprehensively investigate function and structure of the brain in SUD. RESULTS In this meta-analysis, 39 independent studies with 47 datasets related to resting-state functional brain activity (1444 SUD patients; 1446 healthy controls [HCs]) were included, as well as 77 studies with 89 datasets for GMV (3457 SUD patients; 3774 HCs). Patients with SUD showed the decreased resting-state functional brain activity in the bilateral anterior cingulate cortex/medial prefrontal cortex (ACC/mPFC). For the VBM meta-analysis, patients with SUD showed the reduced GMV in the bilateral ACC/mPFC, insula, thalamus extending to striatum, and left sensorimotor cortex. CONCLUSIONS This multimodal meta-analysis exhibited that SUD shows common impairment in both function and structure in the ACC/mPFC, suggesting that the deficits in functional and structural domains could be correlated together. In addition, a few regions exhibited only structural impairment in SUD, including the insula, thalamus, striatum, and sensorimotor areas.
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Affiliation(s)
- Hong Yan
- Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou, China
- Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Shu Xiao
- Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou, China
- Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Siying Fu
- Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou, China
- Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Jiaying Gong
- Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
- Department of Radiology, Six Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Zhangzhang Qi
- Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou, China
- Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Guanmao Chen
- Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou, China
- Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Pan Chen
- Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou, China
- Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Guixian Tang
- Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou, China
- Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Ting Su
- Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou, China
- Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Zibin Yang
- Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou, China
- Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
| | - Ying Wang
- Medical Imaging Center, First Affiliated Hospital of Jinan University, Guangzhou, China
- Institute of Molecular and Functional Imaging, Jinan University, Guangzhou, China
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Jenni S, Ludwig-Peisker O, Jagannathan V, Lapsina S, Stirn M, Hofmann-Lehmann R, Bogdanov N, Schetle N, Giger U, Leeb T, Bogdanova A. Methemoglobinemia, Increased Deformability and Reduced Membrane Stability of Red Blood Cells in a Cat with a CYB5R3 Splice Defect. Cells 2023; 12:cells12070991. [PMID: 37048064 PMCID: PMC10093206 DOI: 10.3390/cells12070991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/16/2023] [Accepted: 03/22/2023] [Indexed: 04/14/2023] Open
Abstract
Methemoglobinemia is an acquired or inherited condition resulting from oxidative stress or dysfunction of the NADH-cytochrome b5 reductase or associated pathways. This study describes the clinical, pathophysiological, and molecular genetic features of a cat with hereditary methemoglobinemia. Whole genome sequencing and mRNA transcript analyses were performed in affected and control cats. Co-oximetry, ektacytometry, Ellman's assay for reduced glutathione concentrations, and CYB5R activity were assessed. A young adult European domestic shorthair cat decompensated at induction of anesthesia and was found to have persistent methemoglobinemia of 39 ± 8% (reference range < 3%) of total hemoglobin which could be reversed upon intravenous methylene blue injection. The erythrocytic CYB5R activity was 20 ± 6% of normal. Genetic analyses revealed a single homozygous base exchange at the beginning of intron 3 of the CYB5R3 gene, c.226+5G>A. Subsequent mRNA studies confirmed a splice defect and demonstrated expression of two mutant CYB5R3 transcripts. Erythrocytic glutathione levels were twice that of controls. Mild microcytosis, echinocytes, and multiple Ca2+-filled vesicles were found in the affected cat. Erythrocytes were unstable at high osmolarities although highly deformable as follows from the changes in elongation index and maximal-tolerated osmolarity. Clinicopathological presentation of this cat was similar to other cats with CYB5R3 deficiency. We found that methemoglobinemia is associated with an increase in red blood cell fragility and deformability, glutathione overload, and morphological alterations typical for stress erythropoiesis.
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Affiliation(s)
- Sophia Jenni
- Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Odette Ludwig-Peisker
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland
| | - Vidhya Jagannathan
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland
| | - Sandra Lapsina
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Martina Stirn
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Regina Hofmann-Lehmann
- Clinical Laboratory, Department of Clinical Diagnostics and Services, and Center for Clinical Studies, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Nikolay Bogdanov
- Red Blood Cell Group, Institute of Veterinary Physiology and the Center for Clinical Studies, Vetsuisse Faculty Zurich, University of Zurich, 8057 Zurich, Switzerland
| | - Nelli Schetle
- Red Blood Cell Group, Institute of Veterinary Physiology and the Center for Clinical Studies, Vetsuisse Faculty Zurich, University of Zurich, 8057 Zurich, Switzerland
| | - Urs Giger
- Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, 8057 Zurich, Switzerland
| | - Tosso Leeb
- Institute of Genetics, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland
| | - Anna Bogdanova
- Red Blood Cell Group, Institute of Veterinary Physiology and the Center for Clinical Studies, Vetsuisse Faculty Zurich, University of Zurich, 8057 Zurich, Switzerland
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Coccarelli A, Nelson MD. Modeling Reactive Hyperemia to Better Understand and Assess Microvascular Function: A Review of Techniques. Ann Biomed Eng 2023; 51:479-492. [PMID: 36709231 PMCID: PMC9928923 DOI: 10.1007/s10439-022-03134-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 12/25/2022] [Indexed: 01/30/2023]
Abstract
Reactive hyperemia is a well-established technique for the non-invasive evaluation of the peripheral microcirculatory function, measured as the magnitude of limb re-perfusion after a brief period of ischemia. Despite widespread adoption by researchers and clinicians alike, many uncertainties remain surrounding interpretation, compounded by patient-specific confounding factors (such as blood pressure or the metabolic rate of the ischemic limb). Mathematical modeling can accelerate our understanding of the physiology underlying the reactive hyperemia response and guide in the estimation of quantities which are difficult to measure experimentally. In this work, we aim to provide a comprehensive guide for mathematical modeling techniques that can be used for describing the key phenomena involved in the reactive hyperemia response, alongside their limitations and advantages. The reported methodologies can be used for investigating specific reactive hyperemia aspects alone, or can be combined into a computational framework to be used in (pre-)clinical settings.
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Affiliation(s)
- Alberto Coccarelli
- Zienkiewicz Centre for Computational Engineering, Faculty of Science and Engineering, Swansea University, Swansea, UK.
| | - Michael D Nelson
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, USA
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Grigorev GV, Lebedev AV, Wang X, Qian X, Maksimov GV, Lin L. Advances in Microfluidics for Single Red Blood Cell Analysis. BIOSENSORS 2023; 13:117. [PMID: 36671952 PMCID: PMC9856164 DOI: 10.3390/bios13010117] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 12/04/2022] [Accepted: 12/23/2022] [Indexed: 05/24/2023]
Abstract
The utilizations of microfluidic chips for single RBC (red blood cell) studies have attracted great interests in recent years to filter, trap, analyze, and release single erythrocytes for various applications. Researchers in this field have highlighted the vast potential in developing micro devices for industrial and academia usages, including lab-on-a-chip and organ-on-a-chip systems. This article critically reviews the current state-of-the-art and recent advances of microfluidics for single RBC analyses, including integrated sensors and microfluidic platforms for microscopic/tomographic/spectroscopic single RBC analyses, trapping arrays (including bifurcating channels), dielectrophoretic and agglutination/aggregation studies, as well as clinical implications covering cancer, sepsis, prenatal, and Sickle Cell diseases. Microfluidics based RBC microarrays, sorting/counting and trapping techniques (including acoustic, dielectrophoretic, hydrodynamic, magnetic, and optical techniques) are also reviewed. Lastly, organs on chips, multi-organ chips, and drug discovery involving single RBC are described. The limitations and drawbacks of each technology are addressed and future prospects are discussed.
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Affiliation(s)
- Georgii V. Grigorev
- Data Science and Information Technology Research Center, Tsinghua Berkeley Shenzhen Institute, Tsinghua University, Shenzhen 518055, China
- Mechanical Engineering Department, University of California in Berkeley, Berkeley, CA 94720, USA
- School of Information Technology, Cherepovets State University, 162600 Cherepovets, Russia
| | - Alexander V. Lebedev
- Machine Building Department, Bauman Moscow State University, 105005 Moscow, Russia
| | - Xiaohao Wang
- Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Xiang Qian
- Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - George V. Maksimov
- Faculty of Biology, Lomonosov Moscow State University, 119991 Moscow, Russia
- Physical metallurgy Department, Federal State Autonomous Educational Institution of Higher Education National Research Technological University “MISiS”, 119049 Moscow, Russia
| | - Liwei Lin
- Mechanical Engineering Department, University of California in Berkeley, Berkeley, CA 94720, USA
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10
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Rajeev A, Mahto SS, Mishra V. Climate warming and summer monsoon breaks drive compound dry and hot extremes in India. iScience 2022; 25:105377. [PMID: 36345335 PMCID: PMC9636558 DOI: 10.1016/j.isci.2022.105377] [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: 05/12/2022] [Revised: 09/05/2022] [Accepted: 10/13/2022] [Indexed: 11/06/2022] Open
Abstract
Considering the severe impacts of compound dry and hot extremes, we examine the primary drivers of CDHEs during the summer monsoon in India. Using ERA5 reanalysis, we show that most of the CDHEs in India occur during the droughts caused by the summer monsoon rainfall deficit. Despite a decline in the frequency of summer monsoon droughts in recent decades, increased CDHEs are mainly driven by warming and dry spells during the summer monsoon particularly in the Northeast, central northeast, and west central regions. A strong land-atmospheric coupling during droughts in the summer monsoon season leads to frequent CDHEs in the Northwest and southern peninsular regions. Furthermore, regional variations in land-atmospheric coupling cause substantial differences in the CDHE occurrence in different parts of the country. Summer monsoon rainfall variability and increased warming can pose a greater risk of compound dry and hot extremes with severe impacts on various sectors in India.
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Affiliation(s)
- Akshay Rajeev
- Earth Sciences, Indian Institute of Technology (IIT) Gandhinagar, Gandhinagar, Gujarat, India
| | - Shanti Shwarup Mahto
- Earth Sciences, Indian Institute of Technology (IIT) Gandhinagar, Gandhinagar, Gujarat, India
| | - Vimal Mishra
- Earth Sciences, Indian Institute of Technology (IIT) Gandhinagar, Gandhinagar, Gujarat, India
- Civil Engineering, Indian Institute of Technology (IIT) Gandhinagar, Gandhinagar, Gujarat, India
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11
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Vujovic F, Hunter N, Farahani RM. Notch ankyrin domain: evolutionary rise of a thermodynamic sensor. Cell Commun Signal 2022; 20:66. [PMID: 35585601 PMCID: PMC9118731 DOI: 10.1186/s12964-022-00886-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 04/21/2022] [Indexed: 12/19/2022] Open
Abstract
Notch signalling pathway plays a key role in metazoan biology by contributing to resolution of binary decisions in the life cycle of cells during development. Outcomes such as proliferation/differentiation dichotomy are resolved by transcriptional remodelling that follows a switch from Notchon to Notchoff state, characterised by dissociation of Notch intracellular domain (NICD) from DNA-bound RBPJ. Here we provide evidence that transitioning to the Notchoff state is regulated by heat flux, a phenomenon that aligns resolution of fate dichotomies to mitochondrial activity. A combination of phylogenetic analysis and computational biochemistry was utilised to disclose structural adaptations of Notch1 ankyrin domain that enabled function as a sensor of heat flux. We then employed DNA-based micro-thermography to measure heat flux during brain development, followed by analysis in vitro of the temperature-dependent behaviour of Notch1 in mouse neural progenitor cells. The structural capacity of NICD to operate as a thermodynamic sensor in metazoans stems from characteristic enrichment of charged acidic amino acids in β-hairpins of the ankyrin domain that amplify destabilising inter-residue electrostatic interactions and render the domain thermolabile. The instability emerges upon mitochondrial activity which raises the perinuclear and nuclear temperatures to 50 °C and 39 °C, respectively, leading to destabilization of Notch1 transcriptional complex and transitioning to the Notchoff state. Notch1 functions a metazoan thermodynamic sensor that is switched on by intercellular contacts, inputs heat flux as a proxy for mitochondrial activity in the Notchon state via the ankyrin domain and is eventually switched off in a temperature-dependent manner. Video abstract
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Affiliation(s)
- Filip Vujovic
- IDR/Westmead Institute for Medical Research, Westmead, NSW, 2145, Australia.,School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, 2006, Australia
| | - Neil Hunter
- IDR/Westmead Institute for Medical Research, Westmead, NSW, 2145, Australia
| | - Ramin M Farahani
- IDR/Westmead Institute for Medical Research, Westmead, NSW, 2145, Australia. .,School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, 2006, Australia.
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12
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Neural Pericytes: A genomic archival state programmed by CHromatin topology. Eur J Cell Biol 2022; 101:151211. [DOI: 10.1016/j.ejcb.2022.151211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/04/2022] [Accepted: 02/25/2022] [Indexed: 11/22/2022] Open
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13
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Wan J, Zhou S, Mea HJ, Guo Y, Ku H, Urbina BM. Emerging Roles of Microfluidics in Brain Research: From Cerebral Fluids Manipulation to Brain-on-a-Chip and Neuroelectronic Devices Engineering. Chem Rev 2022; 122:7142-7181. [PMID: 35080375 DOI: 10.1021/acs.chemrev.1c00480] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Remarkable progress made in the past few decades in brain research enables the manipulation of neuronal activity in single neurons and neural circuits and thus allows the decipherment of relations between nervous systems and behavior. The discovery of glymphatic and lymphatic systems in the brain and the recently unveiled tight relations between the gastrointestinal (GI) tract and the central nervous system (CNS) further revolutionize our understanding of brain structures and functions. Fundamental questions about how neurons conduct two-way communications with the gut to establish the gut-brain axis (GBA) and interact with essential brain components such as glial cells and blood vessels to regulate cerebral blood flow (CBF) and cerebrospinal fluid (CSF) in health and disease, however, remain. Microfluidics with unparalleled advantages in the control of fluids at microscale has emerged recently as an effective approach to address these critical questions in brain research. The dynamics of cerebral fluids (i.e., blood and CSF) and novel in vitro brain-on-a-chip models and microfluidic-integrated multifunctional neuroelectronic devices, for example, have been investigated. This review starts with a critical discussion of the current understanding of several key topics in brain research such as neurovascular coupling (NVC), glymphatic pathway, and GBA and then interrogates a wide range of microfluidic-based approaches that have been developed or can be improved to advance our fundamental understanding of brain functions. Last, emerging technologies for structuring microfluidic devices and their implications and future directions in brain research are discussed.
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Affiliation(s)
- Jiandi Wan
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Sitong Zhou
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Hing Jii Mea
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
| | - Yaojun Guo
- Department of Electrical and Computer Engineering, University of California, Davis, California 95616, United States
| | - Hansol Ku
- Department of Electrical and Computer Engineering, University of California, Davis, California 95616, United States
| | - Brianna M Urbina
- Biochemistry, Molecular, Cellular and Developmental Biology Program, University of California, Davis, California 95616, United States
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14
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Polimeni JR, Lewis LD. Imaging faster neural dynamics with fast fMRI: A need for updated models of the hemodynamic response. Prog Neurobiol 2021; 207:102174. [PMID: 34525404 PMCID: PMC8688322 DOI: 10.1016/j.pneurobio.2021.102174] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 07/30/2021] [Accepted: 09/08/2021] [Indexed: 12/20/2022]
Abstract
Fast fMRI enables the detection of neural dynamics over timescales of hundreds of milliseconds, suggesting it may provide a new avenue for studying subsecond neural processes in the human brain. The magnitudes of these fast fMRI dynamics are far greater than predicted by canonical models of the hemodynamic response. Several studies have established nonlinear properties of the hemodynamic response that have significant implications for fast fMRI. We first review nonlinear properties of the hemodynamic response function that may underlie fast fMRI signals. We then illustrate the breakdown of canonical hemodynamic response models in the context of fast neural dynamics. We will then argue that the canonical hemodynamic response function is not likely to reflect the BOLD response to neuronal activity driven by sparse or naturalistic stimuli or perhaps to spontaneous neuronal fluctuations in the resting state. These properties suggest that fast fMRI is capable of tracking surprisingly fast neuronal dynamics, and we discuss the neuroscientific questions that could be addressed using this approach.
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Affiliation(s)
- Jonathan R Polimeni
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Radiology, Harvard Medical School, Boston, MA, USA; Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Laura D Lewis
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA; Department of Biomedical Engineering, Boston University, Boston, MA, USA.
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15
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Qiang Y, Liu J, Dao M, Du E. In vitro assay for single-cell characterization of impaired deformability in red blood cells under recurrent episodes of hypoxia. LAB ON A CHIP 2021; 21:3458-3470. [PMID: 34378625 PMCID: PMC8440480 DOI: 10.1039/d1lc00598g] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Red blood cells (RBCs) are subjected to recurrent changes in shear stress and oxygen tension during blood circulation. The cyclic shear stress has been identified as an important factor that alone can weaken cell mechanical deformability. The effects of cyclic hypoxia on cellular biomechanics have yet to be fully investigated. As the oxygen affinity of hemoglobin plays a key role in the biological function and mechanical performance of RBCs, the repeated transitions of hemoglobin between its R (high oxygen tension) and T (low oxygen tension) states may impact their mechanical behavior. The present study focuses on developing a novel microfluidic-based assay for characterization of the effects of cyclic hypoxia on cell biomechanics. The capability of this assay is demonstrated by a longitudinal study of individual RBCs in health and sickle cell disease subjected to cyclic hypoxia conditions of various durations and levels of low oxygen tension. The viscoelastic properties of cell membranes are extracted from tensile stretching and relaxation processes of RBCs induced by the electrodeformation technique. Results demonstrate that cyclic hypoxia alone can significantly reduce cell deformability, similar to the fatigue damage accumulated through cyclic mechanical loading. RBCs affected by sickle cell disease are less deformable (significantly higher membrane shear modulus and viscosity) than normal RBCs. The fatigue resistance of sickle RBCs to the cyclic hypoxia challenge is significantly inferior to that of normal RBCs, and this trend is more significant in mature erythrocytes of sickle cells. When the oxygen affinity of sickle hemoglobin is enhanced by anti-sickling drug treatment of 5-hydroxymethyl-2-furfural (5-HMF), sickle RBCs show ameliorated resistance to fatigue damage induced by cyclic hypoxia. These results indicate an important biophysical mechanism underlying RBC senescence in which the cyclic hypoxia challenge alone can lead to mechanical degradation of the RBC membrane. We envision that the application of this assay can be further extended to RBCs in other blood diseases and other cell types.
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Affiliation(s)
- Yuhao Qiang
- Ocean and Mechanical Engineering, Florida Atlantic University, 777 Glades Rd., Boca Raton, Florida, USA.
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, Massachusetts, USA.
| | - Jia Liu
- Ocean and Mechanical Engineering, Florida Atlantic University, 777 Glades Rd., Boca Raton, Florida, USA.
| | - Ming Dao
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, Massachusetts, USA.
| | - E Du
- Ocean and Mechanical Engineering, Florida Atlantic University, 777 Glades Rd., Boca Raton, Florida, USA.
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16
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Dotsenko OI, Mischenko АМ, Taradina GV. Vibration influence on the O2-dependent processes activity in human erythrocytes. REGULATORY MECHANISMS IN BIOSYSTEMS 2021. [DOI: 10.15421/022162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The early signs of vibration effects on the human body are microcirculation and transcapillary metabolism disorders, accompanied by disruption of the supply to and utilization of oxygen in the tissues and organs. However, there are few experimental studies aimed at finding targets of vibration in cells and determining the action mechanism of vibration. In in vitro experiments, human erythrocytes in buffer solution were exposed to low-frequency vibration (frequency range 8–32 Hz, amplitudes 0.5–0.9 mm) for 3 hours. The dynamics of the accumulation of membrane-bound catalase and hemoglobin and the distribution of ligand hemoglobin in the membrane-bound fraction were studied as the indicators of functional activity of cells. The choice of these indicators is justified by the participation of catalase and hemoglobin in O2-dependent cellular reactions as a part of protein complexes. Since pО2 is a trigger of conformational transitions in the hemoglobin molecule, simultaneously with oxygen transport, hemoglobin signals to different metabolic systems about oxygen conditions in the environment. The studies revealed that in the conditions of vibration, the activity of membrane-associated catalase increased by 40–50% in the frequency range of 12–24 Hz (amplitude 0.5 ± 0.04 mm), by 20–30% in the amplitude of 0.9 mm, but after about 100–120 min exposure the enzyme activity decreased even below the control level. There was a dose-dependent accumulation of membrane-bound hemoglobin during exposure to vibration. In the membrane-bound fraction of hemoglobin, oxyhemoglobin had the highest content (60–80%), while the content of methemoglobin varied 5–20%. During vibrations in the frequency range 12–28 Hz, 0.5 mm, we recorded 10–30% increase in oxyhemoglobin. With increase in the vibration amplitude (0.9 mm) in the frequency range of 16–32 Hz, constant content of oxyhemoglobin was noted at the beginning of the experiment, which tended to decrease during the last exposure time. Frequency of 32 Hz caused increase in the deoxyhemoglobin content in the membrane-bound fraction. The content of methemoglobin (metHb) in erythrocytes significantly increased during exposure to the frequency range of 12–24 Hz, with the amplitude of 0.5 mm (1.3–2.4 times). During the exposure to frequencies of 28 and 32 Hz, we observed the transition of methemoglobin to hemichrome. The content of methemoglobin in the cells was lower and decreased at the end of the experiment when the vibration amplitude was 0.9 mm. In these experimental conditions, no increase in hemichrome content in the membrane-bound fraction was recorded. Therefore, the degree of binding of catalase and hemoglobin with the membrane of erythrocytes that were exposed to vibration and the changes in the content of ligand forms in the composition of membrane-bound hemoglobin are dose-dependent. Low-frequency vibration initiates O2-dependent processes in erythrocytes. Targets of such an influence are nanobubbles of dissolved air (babstons), retained on the surface of erythrocytes due to Coulomb interactions, capable of coagulation and increase in size under the action of vibration. At first, the consequences of these processes are increase in oxygen content in the surface of erythrocytes, and then decrease as a result of degassing. Thus, increase in oxygen content on the surface initiates redox reactions, whereas decrease in oxygen content leads to reconstruction of metabolic processes oriented at overcoming hypoxia.
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17
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Thiagarajan P, Parker CJ, Prchal JT. How Do Red Blood Cells Die? Front Physiol 2021; 12:655393. [PMID: 33790808 PMCID: PMC8006275 DOI: 10.3389/fphys.2021.655393] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 02/24/2021] [Indexed: 12/24/2022] Open
Abstract
Normal human red blood cells have an average life span of about 120 days in the circulation after which they are engulfed by macrophages. This is an extremely efficient process as macrophages phagocytose about 5 million erythrocytes every second without any significant release of hemoglobin in the circulation. Despite large number of investigations, the precise molecular mechanism by which macrophages recognize senescent red blood cells for clearance remains elusive. Red cells undergo several physicochemical changes as they age in the circulation. Several of these changes have been proposed as a recognition tag for macrophages. Most prevalent hypotheses for red cell clearance mechanism(s) are expression of neoantigens on red cell surface, exposure phosphatidylserine and decreased deformability. While there is some correlation between these changes with aging their causal role for red cell clearance has not been established. Despite plethora of investigations, we still have incomplete understanding of the molecular details of red cell clearance. In this review, we have reviewed the recent data on clearance of senescent red cells. We anticipate recent progresses in in vivo red cell labeling and the explosion of modern proteomic techniques will, in near future, facilitate our understanding of red cell senescence and their destruction.
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Affiliation(s)
- Perumal Thiagarajan
- Center for Translational Research on Inflammatory Diseases (CTRID), Michael E. DeBakey Veterans Affairs Medical Center, Houston, TX, United States.,Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
| | - Charles J Parker
- University of Utah School of Medicine, Salt Lake City, UT, United States
| | - Josef T Prchal
- Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, United States
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18
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Epp R, Schmid F, Weber B, Jenny P. Predicting Vessel Diameter Changes to Up-Regulate Biphasic Blood Flow During Activation in Realistic Microvascular Networks. Front Physiol 2020; 11:566303. [PMID: 33178036 PMCID: PMC7596696 DOI: 10.3389/fphys.2020.566303] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 08/14/2020] [Indexed: 12/26/2022] Open
Abstract
A dense network of blood vessels distributes blood to different regions of the brain. To meet the temporarily and spatially varying energy demand resulting from changes in neuronal activity, the vasculature is able to locally up-regulate the blood supply. However, to which extent diameter changes of different vessel types contribute to the up-regulation, as well as the spatial and temporal characteristics of their changes, are currently unknown. Here, we present a new simulation method, which solves an inverse problem to calculate diameter changes of individual blood vessels needed to achieve predefined blood flow distributions in microvascular networks. This allows us to systematically compare the impact of different vessel types in various regulation scenarios. Moreover, the method offers the advantage that it handles the stochastic nature of blood flow originating from tracking the movement of individual red blood cells. Since the inverse problem is formulated for time-averaged pressures and flow rates, a deterministic approach for calculating the diameter changes is used, which allows us to apply the method for large realistic microvascular networks with high-dimensional parameter spaces. Our results obtained in both artificial and realistic microvascular networks reveal that diameter changes at the level of capillaries enable a very localized regulation of blood flow. In scenarios where only larger vessels, i.e., arterioles, are allowed to adapt, the flow increase cannot be confined to a specific activated region and flow changes spread into neighboring regions. Furthermore, relatively small dilations and constrictions of all vessel types can lead to substantial changes of capillary blood flow distributions. This suggests that small scale regulation is necessary to obtain a localized increase in blood flow.
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Affiliation(s)
- Robert Epp
- Institute of Fluid Dynamics, ETH Zurich, Zurich, Switzerland
| | - Franca Schmid
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Bruno Weber
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
| | - Patrick Jenny
- Institute of Fluid Dynamics, ETH Zurich, Zurich, Switzerland
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19
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Presa JL, Saravia F, Bagi Z, Filosa JA. Vasculo-Neuronal Coupling and Neurovascular Coupling at the Neurovascular Unit: Impact of Hypertension. Front Physiol 2020; 11:584135. [PMID: 33101063 PMCID: PMC7546852 DOI: 10.3389/fphys.2020.584135] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 09/04/2020] [Indexed: 12/18/2022] Open
Abstract
Components of the neurovascular unit (NVU) establish dynamic crosstalk that regulates cerebral blood flow and maintain brain homeostasis. Here, we describe accumulating evidence for cellular elements of the NVU contributing to critical physiological processes such as cerebral autoregulation, neurovascular coupling, and vasculo-neuronal coupling. We discuss how alterations in the cellular mechanisms governing NVU homeostasis can lead to pathological changes in which vascular endothelial and smooth muscle cell, pericyte and astrocyte function may play a key role. Because hypertension is a modifiable risk factor for stroke and accelerated cognitive decline in aging, we focus on hypertension-associated changes on cerebral arteriole function and structure, and the molecular mechanisms through which these may contribute to cognitive decline. We gather recent emerging evidence concerning cognitive loss in hypertension and the link with vascular dementia and Alzheimer’s disease. Collectively, we summarize how vascular dysfunction, chronic hypoperfusion, oxidative stress, and inflammatory processes can uncouple communication at the NVU impairing cerebral perfusion and contributing to neurodegeneration.
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Affiliation(s)
- Jessica L Presa
- Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GA, United States.,Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and Instituto de Biología y Medicina Experimental, CONICET, Buenos Aires, Argentina
| | - Flavia Saravia
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and Instituto de Biología y Medicina Experimental, CONICET, Buenos Aires, Argentina
| | - Zsolt Bagi
- Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GA, United States
| | - Jessica A Filosa
- Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GA, United States
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20
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Saadat A, Huyke DA, Oyarzun DI, Escobar PV, Øvreeide IH, Shaqfeh ESG, Santiago JG. A system for the high-throughput measurement of the shear modulus distribution of human red blood cells. LAB ON A CHIP 2020; 20:2927-2936. [PMID: 32648561 DOI: 10.1039/d0lc00283f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Reduced deformability of red blood cells (RBCs) can affect the hemodynamics of the microcirculation and reduce oxygen transport efficiency. It is also well known that reduced RBC deformability is a signature of various physical disorders, including sepsis, and that the primary determinant of RBC deformability is the membrane shear modulus. To measure the distribution of an individual's RBC shear modulus with high throughput, we a) developed a high-fidelity computational model of RBCs in confined microchannels to inform design decisions; b) created a novel experimental system combining microfluidic flow, imaging, and image analysis; and c) performed automated comparisons between measured quantities and numerical predictions to extract quantitative measures of the RBC shear modulus for each of thousands of cells. We applied our computational simulation platform to construct the appropriate deformability figure(s) of merit to quantify RBC stiffness based on an experimentally measured, steady-state cell shape in flow through a microchannel. In particular, we determined a shape parameter based on the second moment of the cell shape that is sensitive to the changes in the membrane stiffness and cell size. We then conducted microfluidic experiments and developed custom automated image processing codes to identify and track the position and shape of individual RBCs within micro-constrictions. The fabricated microchannels include a square cross-section imaging region (7 by 7 μm) and we applied order 10 kPa pressure differences to induce order 10 mm s-1 cell velocities. The combination of modeling, microfluidics, and imaging enables, for the first time, quantitative measurement of the shear moduli of thousands of RBCs in human blood samples. We demonstrate the high-throughput features by sensitive quantification of the changes in the distribution of RBC stiffness with aging. This combined measurement and computational platform is ultimately intended to diagnose blood cell disorders in patients.
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Affiliation(s)
- Amir Saadat
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
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21
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Dotsenko OI, Mykutska IV, Taradina GV, Boiarska ZO. Potential role of cytoplasmic protein binding to erythrocyte membrane in counteracting oxidative and metabolic stress. REGULATORY MECHANISMS IN BIOSYSTEMS 2020. [DOI: 10.15421/022070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The ability of protein to reversibly bind with membrane components is considered to be one of the oldest mechanisms of cell response to external stimuli. Erythrocytes have a well-developed mechanism of an adaptive response involving sorption-desorption processes, e.g. interactions of key glycolytic enzymes and hemoglobin with band 3 protein. A few publications have shown that under oxidative stress, cytoplasmic enzymes such as catalase, glutathione peroxidase and рeroxiredoxin bind to the erythrocyte membrane. The present work is a continuation of research in this direction to determine the causes and consequences of the interaction of cytoplasmic proteins with the membrane under conditions of oxidative stress and different glucose content. Human erythrocytes were incubated for five hours at 20 °C in an oxidizing medium of AscH – 1 · 10–4 M, Cu2+– 5 · 10–6 M with different glucose content (0–8 mM). Dynamic changes in the accumulation of membrane-bound hemoglobin, the distribution of ligand forms of hemoglobin in the cytoplasmic and membrane-bound fractions, the activity of membrane-associated and cytoplasmic forms of Cu/Zn superoxide dismutase (SOD1) and catalase, H2O2 content in extracellular and intracellular media were recorded. It was shown that binding of catalase and SOD1 to the erythrocyte membrane is initiated by oxidative stress and is a physiological function aimed at complete inactivation of extracellular and H2O2 and protection against their entry into the cell. It was shown that under conditions of glucose depletion and oxidative loading, catalase and SOD1 bind to the erythrocyte membrane, leading to inactivation of these enzymes. Membrane-bound hemoglobin was higher in cells incubated under these conditions than in glucose experiments. Glucose introduced into the incubation medium in an amount 4–8 mM causes complete binding of SOD1 to the membrane of erythrocytes, by involving it in the processes of casein kinase stabilization and glycolytic fluxes regulation. With mild oxidation, the amount of hemoglobin bound to the membrane does not change, indicating the presence of certain binding sites for hemoglobin with membrane proteins. We show that the activity of membrane-bound SOD1 along with the content of ligand forms in the composition of membrane-bound hemoglobin are informative indicators of the metabolic and redox state of erythrocytes.
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22
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Noomuna P, Risinger M, Zhou S, Seu K, Man Y, An R, Sheik DA, Wan J, Little JA, Gurkan UA, Turrini FM, Kalfa T, Low PS. Inhibition of Band 3 tyrosine phosphorylation: a new mechanism for treatment of sickle cell disease. Br J Haematol 2020; 190:599-609. [PMID: 32346864 PMCID: PMC7606656 DOI: 10.1111/bjh.16671] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/19/2020] [Accepted: 03/27/2020] [Indexed: 12/31/2022]
Abstract
Many hypotheses have been proposed to explain how a glutamate to valine substitution in sickle haemoglobin (HbS) can cause sickle cell disease (SCD). We propose and document a new mechanism in which elevated tyrosine phosphorylation of Band 3 initiates sequelae that cause vaso-occlusion and the symptoms of SCD. In this mechanism, denaturation of HbS and release of heme generate intracellular oxidants which cause inhibition of erythrocyte tyrosine phosphatases, thus permitting constitutive tyrosine phosphorylation of Band 3. This phosphorylation in turn induces dissociation of the spectrin-actin cytoskeleton from the membrane, leading to membrane weakening, discharge of membrane-derived microparticles (which initiate the coagulation cascade) and release of cell-free HbS (which consumes nitric oxide) and activates the endothelium to express adhesion receptors). These processes promote vaso-occlusive events which cause SCD. We further show that inhibitors of Syk tyrosine kinase block Band 3 tyrosine phosphorylation, prevent release of cell-free Hb, inhibit discharge of membrane-derived microparticles, increase sickle cell deformability, reduce sickle cell adhesion to human endothelial cells, and enhance sickle cell flow through microcapillaries. In view of reports that imatinib (a Syk inhibitor) successfully treats symptoms of sickle cell disease, we suggest that Syk tyrosine kinase inhibitors warrant repurposing as potential treatments for SCD.
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Affiliation(s)
- Panae Noomuna
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
- Institute for Drug Discovery, Purdue University, West Lafayette, IN, USA
| | - Mary Risinger
- College of Nursing, University of Cincinnati, Cincinnati, OH
| | - Sitong Zhou
- Department of Chemical Engineering, University of California, Davis, CA
| | - Katie Seu
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati
| | - Yuncheng Man
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH
| | - Ran An
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH
| | - Daniel A. Sheik
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
- Institute for Drug Discovery, Purdue University, West Lafayette, IN, USA
| | - Jiandi Wan
- Department of Chemical Engineering, University of California, Davis, CA
| | - Jane A. Little
- Department of Medicine, Division of Hematology/Oncology and UNC Blood Research Center, University of North Carolina, Chapel Hill, NC
| | - Umut A. Gurkan
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, OH
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland
- Department of Orthopaedics, Case Western Reserve University, Cleveland, OH, USA
| | | | - Theodosia Kalfa
- Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Philip S. Low
- Department of Chemistry, Purdue University, West Lafayette, IN, USA
- Institute for Drug Discovery, Purdue University, West Lafayette, IN, USA
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23
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Bogdanova A, Kaestner L, Simionato G, Wickrema A, Makhro A. Heterogeneity of Red Blood Cells: Causes and Consequences. Front Physiol 2020; 11:392. [PMID: 32457644 PMCID: PMC7221019 DOI: 10.3389/fphys.2020.00392] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 04/02/2020] [Indexed: 12/21/2022] Open
Abstract
Mean values of hematological parameters are currently used in the clinical laboratory settings to characterize red blood cell properties. Those include red blood cell indices, osmotic fragility test, eosin 5-maleimide (EMA) test, and deformability assessment using ektacytometry to name a few. Diagnosis of hereditary red blood cell disorders is complemented by identification of mutations in distinct genes that are recognized "molecular causes of disease." The power of these measurements is clinically well-established. However, the evidence is growing that the available information is not enough to understand the determinants of severity of diseases and heterogeneity in manifestation of pathologies such as hereditary hemolytic anemias. This review focuses on an alternative approach to assess red blood cell properties based on heterogeneity of red blood cells and characterization of fractions of cells with similar properties such as density, hydration, membrane loss, redox state, Ca2+ levels, and morphology. Methodological approaches to detect variance of red blood cell properties will be presented. Causes of red blood cell heterogeneity include cell age, environmental stress as well as shear and metabolic stress, and multiple other factors. Heterogeneity of red blood cell properties is also promoted by pathological conditions that are not limited to the red blood cells disorders, but inflammatory state, metabolic diseases and cancer. Therapeutic interventions such as splenectomy and transfusion as well as drug administration also impact the variance in red blood cell properties. Based on the overview of the studies in this area, the possible applications of heterogeneity in red blood cell properties as prognostic and diagnostic marker commenting on the power and selectivity of such markers are discussed.
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Affiliation(s)
- Anna Bogdanova
- Red Blood Cell Research Group, Vetsuisse Faculty, The Zurich Center for Integrative Human Physiology (ZHIP), Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
| | - Lars Kaestner
- Experimental Physics, Dynamics of Fluids, Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany
- Theoretical Medicine and Biosciences, Medical Faculty, Saarland University, Homburg, Germany
| | - Greta Simionato
- Experimental Physics, Dynamics of Fluids, Faculty of Natural Sciences and Technology, Saarland University, Saarbrücken, Germany
- Institute for Clinical and Experimental Surgery, Saarland University, Homburg, Germany
| | - Amittha Wickrema
- Section of Hematology/Oncology, Department of Medicine, University of Chicago, Chicago, IL, United States
| | - Asya Makhro
- Red Blood Cell Research Group, Vetsuisse Faculty, The Zurich Center for Integrative Human Physiology (ZHIP), Institute of Veterinary Physiology, University of Zurich, Zurich, Switzerland
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24
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Laranjinha J, Nunes C, Ledo A, Lourenço C, Rocha B, Barbosa RM. The Peculiar Facets of Nitric Oxide as a Cellular Messenger: From Disease-Associated Signaling to the Regulation of Brain Bioenergetics and Neurovascular Coupling. Neurochem Res 2020; 46:64-76. [PMID: 32193753 DOI: 10.1007/s11064-020-03015-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 03/07/2020] [Accepted: 03/12/2020] [Indexed: 12/13/2022]
Abstract
In this review, we address the regulatory and toxic role of ·NO along several pathways, from the gut to the brain. Initially, we address the role on ·NO in the regulation of mitochondrial respiration with emphasis on the possible contribution to Parkinson's disease via mechanisms that involve its interaction with a major dopamine metabolite, DOPAC. In parallel with initial discoveries of the inhibition of mitochondrial respiration by ·NO, it became clear the potential for toxic ·NO-mediated mechanisms involving the production of more reactive species and the post-translational modification of mitochondrial proteins. Accordingly, we have proposed a novel mechanism potentially leading to dopaminergic cell death, providing evidence that NO synergistically interact with DOPAC in promoting cell death via mechanisms that involve GSH depletion. The modulatory role of NO will be then briefly discussed as a master regulator on brain energy metabolism. The energy metabolism in the brain is central to the understanding of brain function and disease. The core role of ·NO in the regulation of brain metabolism and vascular responses is further substantiated by discussing its role as a mediator of neurovascular coupling, the increase in local microvessels blood flow in response to spatially restricted increase of neuronal activity. The many facets of NO as intracellular and intercellular messenger, conveying information associated with its spatial and temporal concentration dynamics, involve not only the discussion of its reactions and potential targets on a defined biological environment but also the regulation of its synthesis by the family of nitric oxide synthases. More recently, a novel pathway, out of control of NOS, has been the subject of a great deal of controversy, the nitrate:nitrite:NO pathway, adding new perspectives to ·NO biology. Thus, finally, this novel pathway will be addressed in connection with nitrate consumption in the diet and the beneficial effects of protein nitration by reactive nitrogen species.
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Affiliation(s)
- João Laranjinha
- Faculty of Pharmacy, University of Coimbra, Azinhaga Sta. Comba, 3000-548, Coimbra, Portugal. .,Center for Neuroscience and Cell Biology, University of Coimbra, Pólo 1, 3000-504, Coimbra, Portugal.
| | - Carla Nunes
- Faculty of Pharmacy, University of Coimbra, Azinhaga Sta. Comba, 3000-548, Coimbra, Portugal.,Center for Neuroscience and Cell Biology, University of Coimbra, Pólo 1, 3000-504, Coimbra, Portugal
| | - Ana Ledo
- Center for Neuroscience and Cell Biology, University of Coimbra, Pólo 1, 3000-504, Coimbra, Portugal
| | - Cátia Lourenço
- Center for Neuroscience and Cell Biology, University of Coimbra, Pólo 1, 3000-504, Coimbra, Portugal
| | - Bárbara Rocha
- Faculty of Pharmacy, University of Coimbra, Azinhaga Sta. Comba, 3000-548, Coimbra, Portugal.,Center for Neuroscience and Cell Biology, University of Coimbra, Pólo 1, 3000-504, Coimbra, Portugal
| | - Rui M Barbosa
- Faculty of Pharmacy, University of Coimbra, Azinhaga Sta. Comba, 3000-548, Coimbra, Portugal.,Center for Neuroscience and Cell Biology, University of Coimbra, Pólo 1, 3000-504, Coimbra, Portugal
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25
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Racine ML, Dinenno FA. Reduced deformability contributes to impaired deoxygenation-induced ATP release from red blood cells of older adult humans. J Physiol 2019; 597:4503-4519. [PMID: 31310005 DOI: 10.1113/jp278338] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Accepted: 07/15/2019] [Indexed: 12/17/2022] Open
Abstract
KEY POINTS Red blood cells (RBCs) release ATP in response to deoxygenation, which can increase blood flow to help match oxygen supply with tissue metabolic demand. This release of ATP is impaired in RBCs from older adults, but the underlying mechanisms are unknown. In this study, improving RBC deformability in older adults restored deoxygenation-induced ATP release, whereas decreasing RBC deformability in young adults reduced ATP release to the level of that of older adults. In contrast, treating RBCs with a phosphodiesterase 3 inhibitor did not affect ATP release in either age group, possibly due to intact intracellular signalling downstream of deoxygenation as indicated by preserved cAMP and ATP release responses to pharmacological Gi protein activation in RBCs from older adults. These findings are the first to demonstrate that the age-related decrease in RBC deformability is a primary mechanism of impaired deoxygenation-induced ATP release, which may have implications for treating impaired vascular control with advancing age. ABSTRACT In response to haemoglobin deoxygenation, red blood cells (RBCs) release ATP, which binds to endothelial purinergic receptors and stimulates vasodilatation. This ATP release is impaired in RBCs from older vs. young adults, but the underlying mechanisms are unknown. Using isolated RBCs from young (24 ± 1 years) and older (65 ± 2 years) adults, we tested the hypothesis that age-related changes in RBC deformability (Study 1) and cAMP signalling (Study 2) contribute to the impairment. RBC ATP release during normoxia ( P O 2 ∼112 mmHg) and hypoxia ( P O 2 ∼20 mmHg) was quantified with the luciferin-luciferase technique following RBC incubation with Y-27632 (Rho-kinase inhibitor to increase deformability), diamide (cell-stiffening agent), cilostazol (phosphodiesterase 3 inhibitor), or vehicle control. The mean change in RBC ATP release from normoxia to hypoxia in control conditions was significantly impaired in older vs. young (∼50% vs. ∼120%; P < 0.05). RBC deformability was also lower in older vs. young as indicated by a higher RBC transit time (RCTT) measured by blood filtrometry (RCTT: 8.541 ± 0.050 vs. 8.234 ± 0.098 a.u., respectively; P < 0.05). Y-27632 improved RBC deformability (RCTT: 8.228 ± 0.083) and ATP release (111.7 ± 17.2%) in older and diamide decreased RBC deformability (RCTT: 8.955 ± 0.114) and ATP release (67.4 ± 11.8%) in young (P < 0.05), abolishing the age group differences (P > 0.05). Cilostazol did not change ATP release in either age group (P > 0.05), and RBC cAMP and ATP release to pharmacological Gi protein activation was similar in both groups (P > 0.05). We conclude that decreased RBC deformability is a primary contributor to age-related impairments in RBC ATP release, which may have implications for impaired vascular control with advancing age.
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Affiliation(s)
- Matthew L Racine
- Human Cardiovascular Physiology Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523, USA
| | - Frank A Dinenno
- Human Cardiovascular Physiology Laboratory, Department of Health and Exercise Science, Colorado State University, Fort Collins, CO, 80523, USA.,Cardiovascular Research Center, Colorado State University, Fort Collins, CO, 80523, USA
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26
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Cellular Control of Brain Capillary Blood Flow: In Vivo Imaging Veritas. Trends Neurosci 2019; 42:528-536. [PMID: 31255380 DOI: 10.1016/j.tins.2019.05.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 05/19/2019] [Accepted: 05/28/2019] [Indexed: 01/01/2023]
Abstract
The precise modulation of regional cerebral blood flow during neural activation is important for matching local energetic demand and supply and clearing brain metabolites. Here we discuss advances facilitated by high-resolution optical in vivo imaging techniques that for the first time have provided direct visualization of capillary blood flow and its modulation by neural activity. We focus primarily on studies of microvascular flow, mural cell control of vessel diameter, and oxygen level-dependent changes in red blood cell deformability. We also suggest methodological standards for best practices when studying microvascular perfusion, partly motivated by recent controversies about the precise location within the microvascular tree where neurovascular coupling is initiated, and the role of mural cells in the control of vasomotility.
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