51
|
Chadwick W, Boyle JP, Zhou Y, Wang L, Park SS, Martin B, Wang R, Becker KG, Wood WH, Zhang Y, Peers C, Maudsley S. Multiple oxygen tension environments reveal diverse patterns of transcriptional regulation in primary astrocytes. PLoS One 2011; 6:e21638. [PMID: 21738745 PMCID: PMC3124552 DOI: 10.1371/journal.pone.0021638] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Accepted: 06/04/2011] [Indexed: 01/28/2023] Open
Abstract
The central nervous system normally functions at O2 levels which would be regarded as hypoxic by most other tissues. However, most in vitro studies of neurons and astrocytes are conducted under hyperoxic conditions without consideration of O2-dependent cellular adaptation. We analyzed the reactivity of astrocytes to 1, 4 and 9% O2 tensions compared to the cell culture standard of 20% O2, to investigate their ability to sense and translate this O2 information to transcriptional activity. Variance of ambient O2 tension for rat astrocytes resulted in profound changes in ribosomal activity, cytoskeletal and energy-regulatory mechanisms and cytokine-related signaling. Clustering of transcriptional regulation patterns revealed four distinct response pattern groups that directionally pivoted around the 4% O2 tension, or demonstrated coherent ascending/decreasing gene expression patterns in response to diverse oxygen tensions. Immune response and cell cycle/cancer-related signaling pathway transcriptomic subsets were significantly activated with increasing hypoxia, whilst hemostatic and cardiovascular signaling mechanisms were attenuated with increasing hypoxia. Our data indicate that variant O2 tensions induce specific and physiologically-focused transcript regulation patterns that may underpin important physiological mechanisms that connect higher neurological activity to astrocytic function and ambient oxygen environments. These strongly defined patterns demonstrate a strong bias for physiological transcript programs to pivot around the 4% O2 tension, while uni-modal programs that do not, appear more related to pathological actions. The functional interaction of these transcriptional ‘programs’ may serve to regulate the dynamic vascular responsivity of the central nervous system during periods of stress or heightened activity.
Collapse
Affiliation(s)
- Wayne Chadwick
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - John P. Boyle
- Institute for Cardiovascular Research, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds, West Yorkshire, United Kingdom
| | - Yu Zhou
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Liyun Wang
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Sung-Soo Park
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Bronwen Martin
- Metabolism Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Rui Wang
- Metabolism Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Kevin G. Becker
- Gene Expression and Genomics Unit, Research Resources Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - William H. Wood
- Gene Expression and Genomics Unit, Research Resources Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Yongqing Zhang
- Gene Expression and Genomics Unit, Research Resources Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Chris Peers
- Institute for Cardiovascular Research, Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Leeds, West Yorkshire, United Kingdom
- * E-mail: (SM); (CP)
| | - Stuart Maudsley
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
- * E-mail: (SM); (CP)
| |
Collapse
|
52
|
Chadwick W, Mitchell N, Caroll J, Zhou Y, Park SS, Wang L, Becker KG, Zhang Y, Lehrmann E, Wood WH, Martin B, Maudsley S. Amitriptyline-mediated cognitive enhancement in aged 3×Tg Alzheimer's disease mice is associated with neurogenesis and neurotrophic activity. PLoS One 2011; 6:e21660. [PMID: 21738757 PMCID: PMC3124550 DOI: 10.1371/journal.pone.0021660] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Accepted: 06/07/2011] [Indexed: 01/22/2023] Open
Abstract
Approximately 35 million people worldwide suffer from Alzheimer's disease (AD). Existing therapeutics, while moderately effective, are currently unable to stem the widespread rise in AD prevalence. AD is associated with an increase in amyloid beta (Aβ) oligomers and hyperphosphorylated tau, along with cognitive impairment and neurodegeneration. Several antidepressants have shown promise in improving cognition and alleviating oxidative stress in AD but have failed as long-term therapeutics. In this study, amitriptyline, an FDA-approved tricyclic antidepressant, was administered orally to aged and cognitively impaired transgenic AD mice (3×TgAD). After amitriptyline treatment, cognitive behavior testing demonstrated that there was a significant improvement in both long- and short-term memory retention. Amitriptyline treatment also caused a significant potentiation of non-toxic Aβ monomer with a concomitant decrease in cytotoxic dimer Aβ load, compared to vehicle-treated 3×TgAD controls. In addition, amitriptyline administration caused a significant increase in dentate gyrus neurogenesis as well as increases in expression of neurosynaptic marker proteins. Amitriptyline treatment resulted in increases in hippocampal brain-derived neurotrophic factor protein as well as increased tyrosine phosphorylation of its cognate receptor (TrkB). These results indicate that amitriptyline has significant beneficial actions in aged and damaged AD brains and that it shows promise as a tolerable novel therapeutic for the treatment of AD.
Collapse
Affiliation(s)
- Wayne Chadwick
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Nick Mitchell
- Laboratory of Neurosciences, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Jenna Caroll
- Center for Neurodegenerative Disease Research, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Yu Zhou
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Sung-Soo Park
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Liyun Wang
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Kevin G. Becker
- Genomics Unit, Research Resources Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Yongqing Zhang
- Genomics Unit, Research Resources Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Elin Lehrmann
- Genomics Unit, Research Resources Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - William H. Wood
- Genomics Unit, Research Resources Branch, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Bronwen Martin
- Metabolism Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
| | - Stuart Maudsley
- Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health, Baltimore, Maryland, United States of America
- * E-mail:
| |
Collapse
|
53
|
Zhou Y, Yi T, Park SS, Chadwick W, Shen RF, Wu WW, Martin B, Maudsley S. Rapid and enhanced proteolytic digestion using electric-field-oriented enzyme reactor. J Proteomics 2011; 74:1030-5. [PMID: 21338726 DOI: 10.1016/j.jprot.2011.02.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 01/25/2011] [Accepted: 02/06/2011] [Indexed: 01/26/2023]
Abstract
We have created a novel enzyme reactor using electric field-mediated orientation and immobilization of proteolytic enzymes (trypsin/chymotrypsin) on biocompatible PVDF membranes in a continuous flow-through chamber. Using less than 5min, this reactor in various enzyme combinations can produce enhanced rapid digestion for standardized prototypic proteins, hydrophilic proteins and hydrophobic transmembrane proteins when compared to in-solution techniques. With improved digestive efficiency, our reactor improved the overall functional analysis of lipid raft proteomes by identifying more closely functionally linked proteins and elucidated a richer set of biological processes and pathways linked to the proteins than traditional in-solution methods.
Collapse
Affiliation(s)
- Yu Zhou
- Receptor Pharmacology Unit, Laboratory of Neuroscience, National Institute on Aging, Biomedical Research Center, Baltimore, MD, USA
| | | | | | | | | | | | | | | |
Collapse
|