1
|
Hayes CA, Ashmore BG, Vijayasankar A, Marshall JP, Ashpole NM. Insulin-Like Growth Factor-1 Differentially Modulates Glutamate-Induced Toxicity and Stress in Cells of the Neurogliovascular Unit. Front Aging Neurosci 2021; 13:751304. [PMID: 34887742 PMCID: PMC8650493 DOI: 10.3389/fnagi.2021.751304] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 10/08/2021] [Indexed: 11/29/2022] Open
Abstract
The age-related reduction in circulating levels of insulin-like growth factor-1 (IGF-1) is associated with increased risk of stroke and neurodegenerative diseases in advanced age. Numerous reports highlight behavioral and physiological deficits in blood-brain barrier function and neurovascular communication when IGF-1 levels are low. Administration of exogenous IGF-1 reduces the extent of tissue damage and sensorimotor deficits in animal models of ischemic stroke, highlighting the critical role of IGF-1 as a regulator of neurovascular health. The beneficial effects of IGF-1 in the nervous system are often attributed to direct actions on neurons; however, glial cells and the cerebrovasculature are also modulated by IGF-1, and systemic reductions in circulating IGF-1 likely influence the viability and function of the entire neuro-glio-vascular unit. We recently observed that reduced IGF-1 led to impaired glutamate handling in astrocytes. Considering glutamate excitotoxicity is one of the main drivers of neurodegeneration following ischemic stroke, the age-related loss of IGF-1 may also compromise neural function indirectly by altering the function of supporting glia and vasculature. In this study, we assess and compare the effects of IGF-1 signaling on glutamate-induced toxicity and reactive oxygen species (ROS)-produced oxidative stress in primary neuron, astrocyte, and brain microvascular endothelial cell cultures. Our findings verify that neurons are highly susceptible to excitotoxicity, in comparison to astrocytes or endothelial cells, and that a prolonged reduction in IGFR activation increases the extent of toxicity. Moreover, prolonged IGFR inhibition increased the susceptibility of astrocytes to glutamate-induced toxicity and lessened their ability to protect neurons from excitotoxicity. Thus, IGF-1 promotes neuronal survival by acting directly on neurons and indirectly on astrocytes. Despite increased resistance to excitotoxic death, both astrocytes and cerebrovascular endothelial cells exhibit acute increases in glutamate-induced ROS production and mitochondrial dysfunction when IGFR is inhibited at the time of glutamate stimulation. Together these data highlight that each cell type within the neuro-glio-vascular unit differentially responds to stress when IGF-1 signaling was impaired. Therefore, the reductions in circulating IGF-1 observed in advanced age are likely detrimental to the health and function of the entire neuro-glio-vascular unit.
Collapse
Affiliation(s)
- Cellas A Hayes
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University of Mississippi, Oxford, MS, United States
| | - Brandon G Ashmore
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University of Mississippi, Oxford, MS, United States
| | - Akshaya Vijayasankar
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University of Mississippi, Oxford, MS, United States
| | - Jessica P Marshall
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University of Mississippi, Oxford, MS, United States
| | - Nicole M Ashpole
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University of Mississippi, Oxford, MS, United States.,Research Institute of Pharmaceutical Sciences, University of Mississippi School of Pharmacy, University of Mississippi, Oxford, MS, United States
| |
Collapse
|
2
|
Slavin BR, Sarhane KA, von Guionneau N, Hanwright PJ, Qiu C, Mao HQ, Höke A, Tuffaha SH. Insulin-Like Growth Factor-1: A Promising Therapeutic Target for Peripheral Nerve Injury. Front Bioeng Biotechnol 2021; 9:695850. [PMID: 34249891 PMCID: PMC8264584 DOI: 10.3389/fbioe.2021.695850] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 06/02/2021] [Indexed: 01/27/2023] Open
Abstract
Patients who sustain peripheral nerve injuries (PNIs) are often left with debilitating sensory and motor loss. Presently, there is a lack of clinically available therapeutics that can be given as an adjunct to surgical repair to enhance the regenerative process. Insulin-like growth factor-1 (IGF-1) represents a promising therapeutic target to meet this need, given its well-described trophic and anti-apoptotic effects on neurons, Schwann cells (SCs), and myocytes. Here, we review the literature regarding the therapeutic potential of IGF-1 in PNI. We appraised the literature for the various approaches of IGF-1 administration with the aim of identifying which are the most promising in offering a pathway toward clinical application. We also sought to determine the optimal reported dosage ranges for the various delivery approaches that have been investigated.
Collapse
Affiliation(s)
- Benjamin R Slavin
- Department of Plastic and Reconstructive Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, United States.,Division of Plastic and Reconstructive Surgery, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Karim A Sarhane
- Department of Plastic and Reconstructive Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Nicholas von Guionneau
- Department of Plastic and Reconstructive Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Phillip J Hanwright
- Department of Plastic and Reconstructive Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Chenhu Qiu
- Department of Materials Science and Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD, United States.,Institute for Nanobiotechnology, Johns Hopkins University, Baltimore, MD, United States
| | - Hai-Quan Mao
- Department of Materials Science and Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD, United States.,Institute for Nanobiotechnology, Johns Hopkins University, Baltimore, MD, United States.,Department of Biomedical Engineering, School of Medicine, Johns Hopkins University, Baltimore, MD, United States.,Translational Tissue Engineering Center, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Ahmet Höke
- Department of Neurology, School of Medicine, Johns Hopkins University, Baltimore, MD, United States.,Department of Neuroscience, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Sami H Tuffaha
- Department of Plastic and Reconstructive Surgery, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
| |
Collapse
|
3
|
Prabhu D, Khan SM, Blackburn K, Marshall JP, Ashpole NM. Loss of insulin-like growth factor-1 signaling in astrocytes disrupts glutamate handling. J Neurochem 2019; 151:689-702. [PMID: 31563149 DOI: 10.1111/jnc.14879] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 09/04/2019] [Accepted: 09/17/2019] [Indexed: 12/25/2022]
Abstract
Insulin-like Growth Factor-1 (IGF-1) has been studied extensively for its ability to promote neuronal growth and excitability. Declining levels of IGF-1 have been correlated with impaired learning and memory as well as an increased risk of neurodegenerative diseases. While neuronal regulation by IGF-1 is well understood, the role of IGF-1 in influencing astrocyte function requires further exploration. Astrocytes regulate many aspects of the brain microenvironment, including controlling glutamate-glutamine cycling, which ultimately supports neuronal metabolism, neurotransmission, and protection from over stimulation. In this study, we examined whether IGF-1 acts through its cognate receptor, IGFR, to alter astrocytic glutamate handling. We utilized both small molecule IGFR inhibitors and Cre-driven genetic approaches to reduce IGFR in vivo and in cultured rodent astrocytes. When IGFR was knocked out of primary astrocytes derived from igfrf/f mice using AAV5-CMV-Cre, significant reductions in glutamate uptake were observed. Similarly, inhibition of IGFR with picropodophyllotoxin for 2 h, as well as 24 h, reduced glutamate uptake in vitro. Mechanistically, short-term inhibition of IGFR resulted in a significant decrease in glutamate transporter availability on the cell surface, as assessed by biotinylation. Long-term inhibition of IGFR led to significant reductions in mRNA expression of glutamate transport machinery, as assessed with qPCR. Reduced glutamate transporter mRNA was also observed in the brains of astrocyte-specific IGFR-deficient mice, three to four months after knock-out was induced with tamoxifen. Interestingly, long-term IGF-1 inhibition also resulted in an increase in adenosine triphosphate-stimulated glutamate release, though no change in adenosine triphosphate-stimulated calcium flux was observed nor were any changes in purinergic receptor protein expression. Together, these data suggest that reduced IGF-1 signaling will favor an accumulation of extrasynaptic glutamate, which may contribute to neurodegeneration in disease states where IGF-1 levels are low. Cover Image for this issue: doi: 10.1111/jnc.14534.
Collapse
Affiliation(s)
- Disha Prabhu
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University, Mississippi, USA
| | - Sariya M Khan
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University, Mississippi, USA
| | - Katherine Blackburn
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University, Mississippi, USA
| | - Jessica P Marshall
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University, Mississippi, USA
| | - Nicole M Ashpole
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University, Mississippi, USA.,Research Institute of Pharmaceutical Sciences, University of Mississippi School of Pharmacy, University, Mississippi, USA
| |
Collapse
|
4
|
Prabhu D, Khan SM, Blackburn K, Marshall JP, Ashpole NM. Loss of insulin-like growth factor-1 signaling in astrocytes disrupts glutamate handling. J Neurochem 2019. [PMID: 31563149 DOI: 10.1111/jnc.14534] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Insulin-like Growth Factor-1 (IGF-1) has been studied extensively for its ability to promote neuronal growth and excitability. Declining levels of IGF-1 have been correlated with impaired learning and memory as well as an increased risk of neurodegenerative diseases. While neuronal regulation by IGF-1 is well understood, the role of IGF-1 in influencing astrocyte function requires further exploration. Astrocytes regulate many aspects of the brain microenvironment, including controlling glutamate-glutamine cycling, which ultimately supports neuronal metabolism, neurotransmission, and protection from over stimulation. In this study, we examined whether IGF-1 acts through its cognate receptor, IGFR, to alter astrocytic glutamate handling. We utilized both small molecule IGFR inhibitors and Cre-driven genetic approaches to reduce IGFR in vivo and in cultured rodent astrocytes. When IGFR was knocked out of primary astrocytes derived from igfrf/f mice using AAV5-CMV-Cre, significant reductions in glutamate uptake were observed. Similarly, inhibition of IGFR with picropodophyllotoxin for 2 h, as well as 24 h, reduced glutamate uptake in vitro. Mechanistically, short-term inhibition of IGFR resulted in a significant decrease in glutamate transporter availability on the cell surface, as assessed by biotinylation. Long-term inhibition of IGFR led to significant reductions in mRNA expression of glutamate transport machinery, as assessed with qPCR. Reduced glutamate transporter mRNA was also observed in the brains of astrocyte-specific IGFR-deficient mice, three to four months after knock-out was induced with tamoxifen. Interestingly, long-term IGF-1 inhibition also resulted in an increase in adenosine triphosphate-stimulated glutamate release, though no change in adenosine triphosphate-stimulated calcium flux was observed nor were any changes in purinergic receptor protein expression. Together, these data suggest that reduced IGF-1 signaling will favor an accumulation of extrasynaptic glutamate, which may contribute to neurodegeneration in disease states where IGF-1 levels are low. Cover Image for this issue: doi: 10.1111/jnc.14534.
Collapse
Affiliation(s)
- Disha Prabhu
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University, Mississippi, USA
| | - Sariya M Khan
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University, Mississippi, USA
| | - Katherine Blackburn
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University, Mississippi, USA
| | - Jessica P Marshall
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University, Mississippi, USA
| | - Nicole M Ashpole
- Department of BioMolecular Sciences, University of Mississippi School of Pharmacy, University, Mississippi, USA.,Research Institute of Pharmaceutical Sciences, University of Mississippi School of Pharmacy, University, Mississippi, USA
| |
Collapse
|
5
|
Castellino N, Longo A, Avitabile T, Russo A, Fallico M, Bonfiglio V, Toro MD, Rejdak R, Nowomiejska K, Murabito P, Furino C, Reibaldi M. Circulating insulin-like growth factor-1: a new clue in the pathogenesis of age-related macular degeneration. Aging (Albany NY) 2018; 10:4241-4247. [PMID: 30594908] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 12/12/2018] [Indexed: 06/09/2023]
Abstract
In order to investigate Insulin-like growth factor-1 (IGF-1) blood levels in male and female age-matched patients affected by early, intermediate, neovascular age related macular degeneration (AMD) and healthy subjects (no AMD) were enrolled in a prospective, observational study. All patients enrolled were classified according to 4 stages classification of AMD from Age-related eye disease study (AREDS). Each subject underwent a complete ophthalmic examination including best corrected visual acuity (BCVA), applanation tonometry, slit-lamp biomicroscopic examination, color fundus photography, optical coherence tomography (OCT) and, if needed, fluorescein angiography. Overall, 224 anti-VEGF naïve subjects including 56 patients in early AMD group, 56 patients in intermediate AMD group, 56 patients in neovascular AMD group and 56 patients in no AMD group were recruited. For each group 28 male patients and 28 female patients were enrolled. IGF-1 hematic levels were significantly higher (p<0.005) in the neovascular AMD group and in the intermediate AMD group in comparison to no AMD group; no significant difference between early AMD group and no AMD group was found. Our analysis has shown an increment of IGF-1 levels in both neovascular and intermediate stage of AMD supporting the hypothesis that IGF-1 may play a role in the pathogenesis of AMD.
Collapse
Affiliation(s)
| | - Antonio Longo
- Policlinico Gaspare Rodolico-University of Catania, Catania, Italy
| | | | - Andrea Russo
- Policlinico Gaspare Rodolico-University of Catania, Catania, Italy
| | - Matteo Fallico
- Policlinico Gaspare Rodolico-University of Catania, Catania, Italy
| | | | - Mario Damiano Toro
- Policlinico Gaspare Rodolico-University of Catania, Catania, Italy
- Department of General Ophthalmology, Medical University in Lublin, Lublin, Poland
| | - Robert Rejdak
- Department of General Ophthalmology, Medical University in Lublin, Lublin, Poland
| | | | - Paolo Murabito
- Policlinico Gaspare Rodolico-University of Catania, Catania, Italy
| | | | - Michele Reibaldi
- Policlinico Gaspare Rodolico-University of Catania, Catania, Italy
| |
Collapse
|
6
|
Castellino N, Longo A, Avitabile T, Russo A, Fallico M, Bonfiglio V, Toro MD, Rejdak R, Nowomiejska K, Murabito P, Furino C, Reibaldi M. Circulating insulin-like growth factor-1: a new clue in the pathogenesis of age-related macular degeneration. Aging (Albany NY) 2018; 10:4241-4247. [PMID: 30594908 PMCID: PMC6326648 DOI: 10.18632/aging.101727] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 12/12/2018] [Indexed: 07/04/2023]
Abstract
In order to investigate Insulin-like growth factor-1 (IGF-1) blood levels in male and female age-matched patients affected by early, intermediate, neovascular age related macular degeneration (AMD) and healthy subjects (no AMD) were enrolled in a prospective, observational study. All patients enrolled were classified according to 4 stages classification of AMD from Age-related eye disease study (AREDS). Each subject underwent a complete ophthalmic examination including best corrected visual acuity (BCVA), applanation tonometry, slit-lamp biomicroscopic examination, color fundus photography, optical coherence tomography (OCT) and, if needed, fluorescein angiography. Overall, 224 anti-VEGF naïve subjects including 56 patients in early AMD group, 56 patients in intermediate AMD group, 56 patients in neovascular AMD group and 56 patients in no AMD group were recruited. For each group 28 male patients and 28 female patients were enrolled. IGF-1 hematic levels were significantly higher (p<0.005) in the neovascular AMD group and in the intermediate AMD group in comparison to no AMD group; no significant difference between early AMD group and no AMD group was found. Our analysis has shown an increment of IGF-1 levels in both neovascular and intermediate stage of AMD supporting the hypothesis that IGF-1 may play a role in the pathogenesis of AMD.
Collapse
Affiliation(s)
| | - Antonio Longo
- Policlinico Gaspare Rodolico-University of Catania, Catania, Italy
| | | | - Andrea Russo
- Policlinico Gaspare Rodolico-University of Catania, Catania, Italy
| | - Matteo Fallico
- Policlinico Gaspare Rodolico-University of Catania, Catania, Italy
| | | | - Mario Damiano Toro
- Policlinico Gaspare Rodolico-University of Catania, Catania, Italy
- Department of General Ophthalmology, Medical University in Lublin, Lublin, Poland
| | - Robert Rejdak
- Department of General Ophthalmology, Medical University in Lublin, Lublin, Poland
| | | | - Paolo Murabito
- Policlinico Gaspare Rodolico-University of Catania, Catania, Italy
| | | | - Michele Reibaldi
- Policlinico Gaspare Rodolico-University of Catania, Catania, Italy
| |
Collapse
|
7
|
Oh H, Pfeiffer RM, Falk RT, Horne HN, Xiang J, Pollak M, Brinton LA, Storniolo AMV, Sherman ME, Gierach GL, Figueroa JD. Serum insulin-like growth factor (IGF)-I and IGF binding protein-3 in relation to terminal duct lobular unit involution of the normal breast in Caucasian and African American women: The Susan G. Komen Tissue Bank. Int J Cancer 2018; 143:496-507. [PMID: 29473153 DOI: 10.1002/ijc.31333] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 02/05/2018] [Accepted: 02/07/2018] [Indexed: 12/12/2022]
Abstract
Lesser degrees of terminal duct lobular unit (TDLU) involution, as reflected by higher numbers of TDLUs and acini/TDLU, are associated with elevated breast cancer risk. In rodent models, the insulin-like growth factor (IGF) system regulates involution of the mammary gland. We examined associations of circulating IGF measures with TDLU involution in normal breast tissues among women without precancerous lesions. Among 715 Caucasian and 283 African American (AA) women who donated normal breast tissue samples to the Komen Tissue Bank between 2009 and 2012 (75% premenopausal), serum concentrations of IGF-I and binding protein (IGFBP)-3 were quantified using enzyme-linked immunosorbent assay. Hematoxilyn and eosin-stained tissue sections were assessed for numbers of TDLUs ("TDLU count"). Zero-inflated Poisson regression models with a robust variance estimator were used to estimate relative risks (RRs) for association of IGF measures (tertiles) with TDLU count by race and menopausal status, adjusting for potential confounders. AA (vs. Caucasian) women had higher age-adjusted mean levels of serum IGF-I (137 vs. 131 ng/mL, p = 0.07) and lower levels of IGFBP-3 (4165 vs. 4684 ng/mL, p < 0.0001). Postmenopausal IGFBP-3 was inversely associated with TDLU count among AA (RRT3vs.T1 = 0.49, 95% CI = 0.28-0.84, p-trend = 0.04) and Caucasian (RRT3vs.T1 =0.64, 95% CI = 0.42-0.98, p-trend = 0.04) women. In premenopausal women, higher IGF-I:IGFBP-3 ratios were associated with higher TDLU count in Caucasian (RRT3vs.T1 =1.33, 95% CI = 1.02-1.75, p-trend = 0.04), but not in AA (RRT3vs.T1 =0.65, 95% CI = 0.42-1.00, p-trend = 0.05), women. Our data suggest a role of the IGF system, particularly IGFBP-3, in TDLU involution of the normal breast, a breast cancer risk factor, among Caucasian and AA women.
Collapse
Affiliation(s)
- Hannah Oh
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD.,Section of Population Science, Rutgers Cancer Institute of New Jersey, New Brunswick, NJ.,Division of Health Policy and Management, College of Health Science, Korea University, Seoul, Republic of Korea
| | - Ruth M Pfeiffer
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD
| | - Roni T Falk
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD
| | - Hisani N Horne
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD.,U.S. Food and Drug Administration, Silver Spring, MD
| | - Jackie Xiang
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD
| | | | - Louise A Brinton
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD
| | - Anna Maria V Storniolo
- Department of Epidemiology, Richard M. Fairbanks School of Public Health, Indiana University, Indianapolis, IN
| | - Mark E Sherman
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD.,Mayo Clinic, Jacksonville, FL
| | - Gretchen L Gierach
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD
| | - Jonine D Figueroa
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD.,Usher Institute of Population Health Sciences and Informatics, Institute of Genomics and Molecular Medicine, Edinburgh Cancer Research Centre, University of Edinburgh, UK
| |
Collapse
|
8
|
Toth P, Tarantini S, Ashpole NM, Tucsek Z, Milne GL, Valcarcel‐Ares NM, Menyhart A, Farkas E, Sonntag WE, Csiszar A, Ungvari Z. IGF-1 deficiency impairs neurovascular coupling in mice: implications for cerebromicrovascular aging. Aging Cell 2015; 14:1034-44. [PMID: 26172407 PMCID: PMC4693458 DOI: 10.1111/acel.12372] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/14/2015] [Indexed: 12/24/2022] Open
Abstract
Aging is associated with marked deficiency in circulating IGF‐1, which has been shown to contribute to age‐related cognitive decline. Impairment of moment‐to‐moment adjustment of cerebral blood flow (CBF) via neurovascular coupling is thought to play a critical role in the genesis of age‐related cognitive impairment. To establish the link between IGF‐1 deficiency and cerebromicrovascular impairment, neurovascular coupling mechanisms were studied in a novel mouse model of IGF‐1 deficiency (Igf1f/f‐TBG‐Cre‐AAV8) and accelerated vascular aging. We found that IGF‐1‐deficient mice exhibit neurovascular uncoupling and show a deficit in hippocampal‐dependent spatial memory test, mimicking the aging phenotype. IGF‐1 deficiency significantly impaired cerebromicrovascular endothelial function decreasing NO mediation of neurovascular coupling. IGF‐1 deficiency also impaired glutamate‐mediated CBF responses, likely due to dysregulation of astrocytic expression of metabotropic glutamate receptors and impairing mediation of CBF responses by eicosanoid gliotransmitters. Collectively, we demonstrate that IGF‐1 deficiency promotes cerebromicrovascular dysfunction and neurovascular uncoupling mimicking the aging phenotype, which are likely to contribute to cognitive impairment.
Collapse
Affiliation(s)
- Peter Toth
- Donald W. Reynolds Department of Geriatric Medicine Reynolds Oklahoma Center on Aging University of Oklahoma Health Sciences Center Oklahoma City OK 73104 USA
- Department of Neurosurgery and Szentagothai Research Center Medical School University of Pecs Pecs 7624 Hungary
| | - Stefano Tarantini
- Donald W. Reynolds Department of Geriatric Medicine Reynolds Oklahoma Center on Aging University of Oklahoma Health Sciences Center Oklahoma City OK 73104 USA
- Department of Physiology University of Oklahoma Health Sciences Center 940 S.L. Young Blvd. Rm. 653 Oklahoma City 73104OK USA
| | - Nicole M. Ashpole
- Donald W. Reynolds Department of Geriatric Medicine Reynolds Oklahoma Center on Aging University of Oklahoma Health Sciences Center Oklahoma City OK 73104 USA
| | - Zsuzsanna Tucsek
- Donald W. Reynolds Department of Geriatric Medicine Reynolds Oklahoma Center on Aging University of Oklahoma Health Sciences Center Oklahoma City OK 73104 USA
| | - Ginger L. Milne
- Division of Clinical Pharmacology Vanderbilt University Medical Center D‐3100 Medical Center North Nashville TN USA
| | - Noa M. Valcarcel‐Ares
- Donald W. Reynolds Department of Geriatric Medicine Reynolds Oklahoma Center on Aging University of Oklahoma Health Sciences Center Oklahoma City OK 73104 USA
| | - Akos Menyhart
- Department of Medical Physics and Informatics Faculty of Medicine and Faculty of Science and Informatics University of Szeged Szeged 6720Hungary
| | - Eszter Farkas
- Department of Medical Physics and Informatics Faculty of Medicine and Faculty of Science and Informatics University of Szeged Szeged 6720Hungary
| | - William E. Sonntag
- Donald W. Reynolds Department of Geriatric Medicine Reynolds Oklahoma Center on Aging University of Oklahoma Health Sciences Center Oklahoma City OK 73104 USA
- The Peggy and Charles Stephenson Cancer Center University of Oklahoma Health Sciences Center Oklahoma City OK 73104 USA
| | - Anna Csiszar
- Donald W. Reynolds Department of Geriatric Medicine Reynolds Oklahoma Center on Aging University of Oklahoma Health Sciences Center Oklahoma City OK 73104 USA
- Department of Neurosurgery and Szentagothai Research Center Medical School University of Pecs Pecs 7624 Hungary
- Department of Physiology University of Oklahoma Health Sciences Center 940 S.L. Young Blvd. Rm. 653 Oklahoma City 73104OK USA
- The Peggy and Charles Stephenson Cancer Center University of Oklahoma Health Sciences Center Oklahoma City OK 73104 USA
| | - Zoltan Ungvari
- Donald W. Reynolds Department of Geriatric Medicine Reynolds Oklahoma Center on Aging University of Oklahoma Health Sciences Center Oklahoma City OK 73104 USA
- Department of Neurosurgery and Szentagothai Research Center Medical School University of Pecs Pecs 7624 Hungary
- Department of Physiology University of Oklahoma Health Sciences Center 940 S.L. Young Blvd. Rm. 653 Oklahoma City 73104OK USA
- The Peggy and Charles Stephenson Cancer Center University of Oklahoma Health Sciences Center Oklahoma City OK 73104 USA
- Department of Pulmonology 1125 Budapest, Diós árok 1/c Semmelweis University Budapest Hungary
| |
Collapse
|