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Kvorjak M, Ruffo E, Tivon Y, So V, Parikh A, Deiters A, Lohmueller J. Conditional Control of Universal CAR T Cells by Cleavable OFF-Switch Adaptors. ACS Synth Biol 2023; 12:2996-3007. [PMID: 37791909 PMCID: PMC10594876 DOI: 10.1021/acssynbio.3c00320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Indexed: 10/05/2023]
Abstract
As living drugs, engineered T cell therapies are revolutionizing disease treatment with their unique functional capabilities. However, they suffer from limitations of potentially unpredictable behavior, toxicities, and nontraditional pharmacokinetics. Engineering conditional control mechanisms responsive to tractable stimuli such as small molecules or light is thus highly desirable. We and others previously developed "universal" chimeric antigen receptors (CARs) that interact with coadministered antibody adaptors to direct target cell killing and T cell activation. Universal CARs are of high therapeutic interest due to their ability to simultaneously target multiple antigens on the same disease or different diseases by combining with adaptors to different antigens. Here, we further enhance the programmability and potential safety of universal CAR T cells by engineering OFF-switch adaptors that can conditionally control CAR activity, including T cell activation, target cell lysis, and transgene expression, in response to a small molecule or light stimulus. Moreover, in adaptor combination assays, OFF-switch adaptors were capable of orthogonal conditional targeting of multiple antigens simultaneously, following Boolean logic. OFF-switch adaptors represent a robust new approach for the precision targeting of universal CAR T cells with potential for enhanced safety.
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Affiliation(s)
- Michael Kvorjak
- UPMC
Hillman Cancer Center, University of Pittsburgh, Pittsburgh, Pennsylvania 15232, United States
- Division
of Surgical Oncology, Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15232, United States
- Department
of Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
- Center
for Systems Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
| | - Elisa Ruffo
- UPMC
Hillman Cancer Center, University of Pittsburgh, Pittsburgh, Pennsylvania 15232, United States
- Division
of Surgical Oncology, Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15232, United States
- Department
of Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
- Center
for Systems Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
| | - Yaniv Tivon
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Victor So
- UPMC
Hillman Cancer Center, University of Pittsburgh, Pittsburgh, Pennsylvania 15232, United States
- Division
of Surgical Oncology, Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15232, United States
- Department
of Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
- Center
for Systems Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
| | - Avani Parikh
- UPMC
Hillman Cancer Center, University of Pittsburgh, Pittsburgh, Pennsylvania 15232, United States
- Division
of Surgical Oncology, Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15232, United States
- Department
of Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
- Center
for Systems Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
| | - Alexander Deiters
- Center
for Systems Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Jason Lohmueller
- UPMC
Hillman Cancer Center, University of Pittsburgh, Pittsburgh, Pennsylvania 15232, United States
- Division
of Surgical Oncology, Department of Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania 15232, United States
- Department
of Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
- Center
for Systems Immunology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
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Kvorjak M, Ruffo E, Tivon Y, So V, Parikh AB, Deiters A, Lohmueller J. Conditional control of universal CAR T cells by cleavable OFF-switch adaptors. bioRxiv 2023:2023.05.22.541664. [PMID: 37292935 PMCID: PMC10245878 DOI: 10.1101/2023.05.22.541664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
As living drugs, engineered T cell therapies are revolutionizing disease treatment with their unique functional capabilities. However, they suffer from limitations of potentially unpredictable behavior, toxicities, and non-traditional pharmacokinetics. Engineering conditional control mechanisms responsive to tractable stimuli such as small molecules or light is thus highly desirable. We and others previously developed "universal" chimeric antigen receptors (CARs) that interact with co-administered antibody adaptors to direct target cell killing and T cell activation. Universal CARs are of high therapeutic interest due to their ability to simultaneously target multiple antigens on the same disease or different diseases by combining with adaptors to different antigens. Here, we further enhance the programmability and potential safety of universal CAR T cells by engineering OFF-switch adaptors that can conditionally control CAR activity, including T cell activation, target cell lysis, and transgene expression, in response to a small molecule or light stimulus. Moreover, in adaptor combination assays, OFF-switch adaptors were capable of orthogonal conditional targeting of multiple antigens simultaneously following Boolean logic. OFF-switch adaptors represent a robust new approach for precision targeting of universal CAR T cells with potential for enhanced safety.
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Affiliation(s)
- Michael Kvorjak
- University of Pittsburgh School of Medicine, Department of Surgery, Pittsburgh, PA 15232, USA
- University of Pittsburgh School of Medicine, Department of Immunology, Pittsburgh, PA 15232, USA
- University of Pittsburgh, Center for Systems Immunology, Pittsburgh, PA 15232, USA
| | - Elisa Ruffo
- University of Pittsburgh School of Medicine, Department of Surgery, Pittsburgh, PA 15232, USA
- University of Pittsburgh School of Medicine, Department of Immunology, Pittsburgh, PA 15232, USA
- University of Pittsburgh, Center for Systems Immunology, Pittsburgh, PA 15232, USA
| | - Yaniv Tivon
- University of Pittsburgh, Department of Chemistry, Pittsburgh, PA 15260, USA
| | - Victor So
- University of Pittsburgh School of Medicine, Department of Surgery, Pittsburgh, PA 15232, USA
- University of Pittsburgh School of Medicine, Department of Immunology, Pittsburgh, PA 15232, USA
- University of Pittsburgh, Center for Systems Immunology, Pittsburgh, PA 15232, USA
| | - Avani B. Parikh
- University of Pittsburgh School of Medicine, Department of Surgery, Pittsburgh, PA 15232, USA
- University of Pittsburgh School of Medicine, Department of Immunology, Pittsburgh, PA 15232, USA
- University of Pittsburgh, Center for Systems Immunology, Pittsburgh, PA 15232, USA
| | - Alexander Deiters
- University of Pittsburgh, Center for Systems Immunology, Pittsburgh, PA 15232, USA
- University of Pittsburgh, Department of Chemistry, Pittsburgh, PA 15260, USA
| | - Jason Lohmueller
- University of Pittsburgh School of Medicine, Department of Surgery, Pittsburgh, PA 15232, USA
- University of Pittsburgh School of Medicine, Department of Immunology, Pittsburgh, PA 15232, USA
- University of Pittsburgh, Center for Systems Immunology, Pittsburgh, PA 15232, USA
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Ruffo E, Butchy AA, Tivon Y, So V, Kvorjak M, Parikh A, Adams EL, Miskov-Zivanov N, Finn OJ, Deiters A, Lohmueller J. Post-translational covalent assembly of CAR and synNotch receptors for programmable antigen targeting. Nat Commun 2023; 14:2463. [PMID: 37160880 PMCID: PMC10169838 DOI: 10.1038/s41467-023-37863-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 04/03/2023] [Indexed: 05/11/2023] Open
Abstract
Chimeric antigen receptors (CARs) and synthetic Notch (synNotch) receptors are engineered cell-surface receptors that sense a target antigen and respond by activating T cell receptor signaling or a customized gene program, respectively. Here, to expand the targeting capabilities of these receptors, we develop "universal" receptor systems for which receptor specificity can be directed post-translationally via covalent attachment of a co-administered antibody bearing a benzylguanine (BG) motif. A SNAPtag self-labeling enzyme is genetically fused to the receptor and reacts with BG-conjugated antibodies for covalent assembly, programming antigen recognition. We demonstrate that activation of SNAP-CAR and SNAP-synNotch receptors can be successfully targeted by clinically relevant BG-conjugated antibodies, including anti-tumor activity of SNAP-CAR T cells in vivo in a human tumor xenograft mouse model. Finally, we develop a mathematical model to better define the parameters affecting universal receptor signaling. SNAP receptors provide a powerful strategy to post-translationally reprogram the targeting specificity of engineered cells.
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Affiliation(s)
- Elisa Ruffo
- UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA, USA
- Division of Surgical Oncology, Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA
- Center for Systems Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Adam A Butchy
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Yaniv Tivon
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Victor So
- UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA, USA
- Division of Surgical Oncology, Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA
- Center for Systems Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Michael Kvorjak
- UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA, USA
- Division of Surgical Oncology, Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA
- Center for Systems Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Avani Parikh
- UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA, USA
- Division of Surgical Oncology, Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA
- Center for Systems Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Eric L Adams
- UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA, USA
- Division of Surgical Oncology, Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA
- Center for Systems Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Natasa Miskov-Zivanov
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Olivera J Finn
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Alexander Deiters
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jason Lohmueller
- UPMC Hillman Cancer Center, University of Pittsburgh, Pittsburgh, PA, USA.
- Division of Surgical Oncology, Department of Surgery, University of Pittsburgh, Pittsburgh, PA, USA.
- Department of Immunology, University of Pittsburgh, Pittsburgh, PA, USA.
- Center for Systems Immunology, University of Pittsburgh, Pittsburgh, PA, USA.
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So V, Khurshid F. Treatment practices and implementation of guidelines for hyperbilirubinemia and rebound hyperbilirubinemia. J Neonatal Perinatal Med 2021; 15:335-343. [PMID: 34542033 DOI: 10.3233/npm-210781] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Hyperbilirubinemia (HB), defined as elevated total serum bilirubin (TSB) levels, commonly affects neonates and requires prompt treatment to prevent neurological complications. Up to 10%of neonates experience rebound hyperbilirubinemia (RHB), requiring re-initiation of treatment. Unfortunately, treatment guidelines lack practical recommendations surrounding subthreshold phototherapy, treatment termination, and RHB investigations. We examined local management practices for HB and RHB treatment in a well newborn nursery. As a secondary aim, we investigated the association between treatment practices and RHB rates. METHODS Retrospective chart review identified neonates treated for hyperbilirubinemia between January 2015 and December 2019 during their birth hospitalization at a tertiary care centre. Standardized data collection sheets were used to record treatment parameters. RESULTS Over the 5-year period, there were 9683 births and 305 (3.15%) neonates received phototherapy. Of the treated cases, 20-25%were subthreshold to practice guideline values. Upon treatment termination 25-55%of cases had TSB levels within 3 mg/dL, which may increase the risk of RHB. In our cohort, 20.3%of treated cases experienced one episode of RHB and 3.9%experienced two episodes of RHB. Although clinicians evaluated neonates for RHB 0-12 hours following treatment termination prior to discharge, many cases were identified in outpatient settings and required re-admission for phototherapy. CONCLUSION When managing HB and RHB, treatment practices such as when to terminate treatment in relation to threshold values, and timing of RHB investigations, are largely inconsistent amongst clinicians. Future studies are required to better understand the landscape of hyperbilirubinemia treatment beyond initiation of phototherapy.
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Affiliation(s)
- V So
- Department of Pediatrics, School of Medicine, Queen's University, Kingston, Ontario, Canada.,Queen's School of Medicine, Queen's University, Kingston, Ontario, Canada
| | - F Khurshid
- Department of Pediatrics, School of Medicine, Queen's University, Kingston, Ontario, Canada
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Kowallis KA, Silfani EM, Kasumu AP, Rong G, So V, Childers WS. Synthetic Control of Signal Flow Within a Bacterial Multi-Kinase Network. ACS Synth Biol 2020; 9:1705-1713. [PMID: 32559383 DOI: 10.1021/acssynbio.0c00043] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The signal processing capabilities of bacterial signaling networks offer immense potential for advanced phospho-signaling systems for synthetic biology. Emerging models suggest that complex development may require interconnections between what were once thought to be isolated signaling arrays. For example, Caulobacter crescentus achieves the feat of asymmetric division by utilizing a novel pseudokinase DivL, which senses the output of one signaling pathway to modulate a second pathway. It has been proposed that DivL reverses signal flow by exploiting conserved kinase conformational changes and protein-protein interactions. We engineered a series of DivL-based modulators to synthetically stimulate reverse signaling of the network in vivo. Stimulation of conformational changes through the DivL signal transmission helix resulted in changes to hallmark features of the network: C. crescentus motility and DivL accumulation at the cell poles. Additionally, mutations to a conserved PAS sensor transmission motif disrupted reverse signaling flow in vivo. We propose that synthetic stimulation and sensor disruption provide strategies to define signaling circuit organization principles for the rational design and validation of synthetic pathways.
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Affiliation(s)
- Kimberly A. Kowallis
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Elayna M. Silfani
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Amanda P. Kasumu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Grace Rong
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Victor So
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - W. Seth Childers
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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Pereira S, O'Dwyer SM, Webber TD, Baker RK, So V, Ellis CE, Yoon JS, Mojibian M, Glavas MM, Karunakaran S, Clee SM, Covey SD, Kieffer TJ. Metabolic effects of leptin receptor knockdown or reconstitution in adipose tissues. Sci Rep 2019; 9:3307. [PMID: 30824713 PMCID: PMC6397253 DOI: 10.1038/s41598-019-39498-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Accepted: 12/31/2018] [Indexed: 01/26/2023] Open
Abstract
The relative contribution of peripheral and central leptin signalling to the regulation of metabolism and the mechanisms through which leptin affects glucose homeostasis have not been fully elucidated. We generated complementary lines of mice with either leptin receptor (Lepr) knockdown or reconstitution in adipose tissues using Cre-lox methodology. Lepr knockdown mice were modestly lighter and had lower plasma insulin concentrations following an oral glucose challenge compared to controls, despite similar insulin sensitivity. We rendered male mice diabetic using streptozotocin (STZ) and found that upon prolonged leptin therapy, Lepr knockdown mice had an accelerated decrease in blood glucose compared to controls that was associated with higher plasma concentrations of leptin and leptin receptor. Mice with transcriptional blockade of Lepr (LeprloxTB/loxTB) were obese and hyperglycemic and reconstitution of Lepr in adipose tissues of LeprloxTB/loxTB mice resulted in males reaching a higher maximal body weight. Although mice with adipose tissue Lepr reconstitution had lower blood glucose levels at several ages, their plasma insulin concentrations during an oral glucose test were elevated. Thus, attenuation or restoration of Lepr in adipocytes alters the plasma insulin profile following glucose ingestion, modifies the glucose-lowering effect of prolonged leptin therapy in insulin-deficient diabetes, and may modulate weight gain.
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Affiliation(s)
- Sandra Pereira
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Shannon M O'Dwyer
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Travis D Webber
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Robert K Baker
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Victor So
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Cara E Ellis
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Ji Soo Yoon
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Majid Mojibian
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Maria M Glavas
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Subashini Karunakaran
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Susanne M Clee
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Scott D Covey
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, Canada
| | - Timothy J Kieffer
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada. .,Department of Surgery, University of British Columbia, Vancouver, BC, Canada.
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Busso N, So V, Péclat A, Gabay C. Mice deficient in leptin (ob/ob) or in liptin receptor (db/db) have a milder form of antigen-induced arthritis. Arthritis Res Ther 2001. [PMCID: PMC3273191 DOI: 10.1186/ar192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Abstract
We report that rats learning a spatial memory task in the Morris water maze show elevated expression of the signal transduction receptor for BDNF and the synaptic associated protein synapsin I in the hippocampus. Nuclease protection assays showed maximal levels of TrkB and synapsin I mRNAs in the hippocampus by the time that asymptotic learning performance had been reached (Day 6). Increases in synapsin I mRNA were matched by changes in synapsin I protein as revealed by western blot analysis. Synapsin I is a downstream effector for the BDNF tyrosine kinase cascade pathway which has important roles in synaptic remodeling and function. Therefore, parallel changes in TrkB and synapsin I mRNAs suggest a role of the BDNF system in synaptic function or adaptation. Levels of TrkB mRNA in the hippocampus were attenuated after learning acquisition (Day 20), but synapsin I mRNA was still elevated, suggesting that the BDNF system may participate in events secondary to learning, such as strengthening of neural circuits. TrkB and synapsin I mRNAs showed an increasing trend in the cerebellum of learning rats and no changes were observed in the caudal cerebral cortex. The selectivity of the changes in trkB and synapsin I, affecting the hippocampus, is in agreement with the role of this structure in processing of spatial information. Behavioral regulation of neurotrophins may provide a molecular basis for the enhanced cognitive function associated with active lifestyles, and guide development of strategies to promote neural healing after CNS injury or disease.
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Affiliation(s)
- F Gómez-Pinilla
- Department of Physiological Science, UCLA, Los Angeles, CA 90095-1527, USA.
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Kesslak JP, So V, Choi J, Cotman CW, Gomez-Pinilla F. Learning upregulates brain-derived neurotrophic factor messenger ribonucleic acid: a mechanism to facilitate encoding and circuit maintenance? Behav Neurosci 1998; 112:1012-9. [PMID: 9733207 DOI: 10.1037/0735-7044.112.4.1012] [Citation(s) in RCA: 169] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Brain-derived neurotrophic factor (BDNF) promotes neuron survival, enhances sprouting, protects neurons against insult, and may be involved in several aspects of learning and memory. In this study, rats trained to locate a submerged platform in a water maze had elevated levels of BDNF messenger ribonucleic acid (mRNA) in the hippocampus (p < .05), a structure associated with spatial memory. BDNF mRNA expression increased after 3 and 6 days but not after 1 day of training in the water maze. A yoked control group that swam without the platform present, to control for physical activity, showed a trend for elevated BDNF mRNA at an intermediate level between the learning and sedentary groups. Other cortical and subcortical areas did not show a significant increase in BDNF mRNA after learning or activity (p > .05). These findings suggest that learning can impact BDNF mRNA expression localized to the brain areas involved in the processing of spatial information. Furthermore, behaviors such as physical activity and learning may help maintain and protect neurons at risk in aging and neurodegenerative disease via increased BDNF expression.
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Affiliation(s)
- J P Kesslak
- Institute for Brain Aging and Department of Neurology, University of California, Irvine 92697-4540, USA.
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Gómez-Pinilla F, So V, Kesslak JP. Spatial learning and physical activity contribute to the induction of fibroblast growth factor: neural substrates for increased cognition associated with exercise. Neuroscience 1998; 85:53-61. [PMID: 9607702 DOI: 10.1016/s0306-4522(97)00576-9] [Citation(s) in RCA: 194] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
New evidence indicates that neural activity regulates the expression of trophic factors in the brain but regulation of these molecules by select aspects of behaviour remains solely a fascinating possibility. We report that following training in the Morris water maze, a spatial memory task, the hippocampus and cerebellum of learning rats exhibited an increase in basic fibroblast growth factor messenger RNA. Basic fibroblast growth factor messenger RNA levels were higher during the learning of the task and decreased once asymptotic performance was reached, suggesting an involvement of basic fibroblast growth factor in learning/memory. An active control group, which exercised for the same time as the learning group but the spatial learning component of the task was minimized, exhibited a minor increase in basic fibroblast growth factor messenger RNA. The intensification of the physical activity component of the task by massed or intensive training resulted in greater increases in basic fibroblast growth factor messenger RNA for both learning and yoked groups, but levels of basic fibroblast growth factor messenger RNA in the learning group remained higher than yoked only in the cerebellum. Changes in basic fibroblast growth factor were accompanied by an increase in astrocyte density in the hippocampus in agreement with described roles of basic fibroblast growth factor in astrocyte proliferation/reactivity. Results suggest that learning potentiates the effects of physical activity on trophic factor induction in select brain regions. Trophic factor involvement in behaviour may provide a molecular basis for the enhanced cognitive function associated with active lifestyles, and guide development of strategies to improve rehabilitation and successful ageing.
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Affiliation(s)
- F Gómez-Pinilla
- Institute for Brain Aging and Dementia and Department of Neurology, University of California, Irvine 92697-4540, USA
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Abstract
Clinical and experimental evidence indicate that physical activity has a positive impact on brain function; however, the molecular bases for how exercise affects the structure and function of the brain are largely unknown. We have investigated the influences of variable periods of voluntary wheel-running on the expression of basic fibroblast growth factor and its mRNA in various brain regions. Nuclease protection assays revealed that the hippocampus was the only region examined exhibiting changes in FGF-2 mRNA as a result of exercise. FGF-2 mRNA increased to reach a peak by the 4th night of wheel-running. FGF-2 immunoreactivity, normally located in the perinuclear area of astrocytes, following exercise became stronger and appeared to spread to the cytoplasm and processes of astrocytes. Quantification of the FGF-2-immunoreactive astrocytes showed an increase in density between 2 and 4 nights of running in discrete regions of the hippocampus. These results demonstrate that exercise regulates FGF-2 expression and suggest that growth factors are likely mediators of the positive effects of exercise on the brain.
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Affiliation(s)
- F Gómez-Pinilla
- Department of Neurology and Institute for Brain Aging and Dementia, University of California at Irvine, 92697-4540, USA.
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Abstract
Of the 50 strains of myxobacteria (mainly cytophagas) tested most were able to solubilize autoclaved feathers but none attacked unmodified feathers. The strain studied most extensively rapidly solubilized up to 80% of the substrate leaving only the resistant shafts. In the absence of a readily assimilable energy source, such as glucose, about 70% of the protein nitrogen solubilized appeared as ammonia which the organism could not use. Glucose exhibited an amino acid sparing effect.
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