1
|
Augustine-Wofford K, Connaughton VP, McCarthy E. Are Hyperglycemia-Induced Changes in the Retina Associated with Diabetes-Correlated Changes in the Brain? A Review from Zebrafish and Rodent Type 2 Diabetes Models. BIOLOGY 2024; 13:477. [PMID: 39056672 PMCID: PMC11273949 DOI: 10.3390/biology13070477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Revised: 06/23/2024] [Accepted: 06/24/2024] [Indexed: 07/28/2024]
Abstract
Diabetes is prevalent worldwide, with >90% of the cases identified as Type 2 diabetes. High blood sugar (hyperglycemia) is the hallmark symptom of diabetes, with prolonged and uncontrolled levels contributing to subsequent complications. Animal models have been used to study these complications, which include retinopathy, nephropathy, and peripheral neuropathy. More recent studies have focused on cognitive behaviors due to the increased risk of dementia/cognitive deficits that are reported to occur in older Type 2 diabetic patients. In this review, we collate the data reported from specific animal models (i.e., mouse, rat, zebrafish) that have been examined for changes in both retina/vision (retinopathy) and brain/cognition, including db/db mice, Goto-Kakizaki rats, Zucker Diabetic Fatty rats, high-fat diet-fed rodents and zebrafish, and hyperglycemic zebrafish induced by glucose immersion. These models were selected because rodents are widely recognized as established models for studying diabetic complications, while zebrafish represent a newer model in this field. Our goal is to (1) summarize the published findings relevant to these models, (2) identify similarities in cellular mechanisms underlying the disease progression that occur in both tissues, and (3) address the hypothesis that hyperglycemic-induced changes in retina precede or predict later complications in brain.
Collapse
Affiliation(s)
| | - Victoria P. Connaughton
- Department of Biology, American University, Washington, DC 20016, USA; (K.A.-W.); (E.M.)
- Center for Neuroscience and Behavior, American University, Washington, DC 20016, USA
| | - Elizabeth McCarthy
- Department of Biology, American University, Washington, DC 20016, USA; (K.A.-W.); (E.M.)
- Center for Neuroscience and Behavior, American University, Washington, DC 20016, USA
| |
Collapse
|
2
|
McCall MA. Pig Models in Retinal Research and Retinal Disease. Cold Spring Harb Perspect Med 2024; 14:a041296. [PMID: 37553210 PMCID: PMC10982707 DOI: 10.1101/cshperspect.a041296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Abstract
The pig has been used as a large animal model in biomedical research for many years and its use continues to increase because induced mutations phenocopy several inherited human diseases. In addition, they are continuous breeders, can be propagated by artificial insemination, have large litter sizes (on the order of mice), and can be genetically manipulated using all of the techniques that are currently available in mice. The pioneering work of Petters and colleagues set the stage for the use of the pig as a model of inherited retinal disease. In the last 10 years, the pig has become a model of choice where specific disease-causing mutations that are not phenocopied in rodents need to be studied and therapeutic approaches explored. The pig is not only used for retinal eye disease but also for the study of the cornea and lens. This review attempts to show how broad the use of the pig has become and how it has contributed to the assessment of treatments for eye disease. In the last 10 years, there have been several reviews that included the use of the pig in biomedical research (see body of the review) that included information about retinal disease. None directly discuss the use of the pig as an animal model for retinal diseases, including inherited diseases, where a single genetic mutation has been identified or for multifactorial diseases such as glaucoma and diabetic retinopathy. Although the pig is used to explore diseases of the cornea and lens, this review focuses on how and why the pig, as a large animal model, is useful for research in neural retinal disease and its treatment.
Collapse
Affiliation(s)
- Maureen A McCall
- Departments of Ophthalmology & Visual Sciences and Anatomical Sciences & Neurobiology, University of Louisville, Louisville, Kentucky 40202, USA
| |
Collapse
|
3
|
Ni MH, Yu Y, Yang Y, Li ZY, Ma T, Xie H, Li SN, Dai P, Cao XY, Cui YY, Zhu JL, Cui GB, Yan LF. Functional-structural decoupling in visual network is associated with cognitive decline in patients with type 2 diabetes mellitus: evidence from a multimodal MRI analysis. Brain Imaging Behav 2024; 18:73-82. [PMID: 37874444 DOI: 10.1007/s11682-023-00801-6] [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] [Accepted: 09/07/2023] [Indexed: 10/25/2023]
Abstract
Type 2 diabetes mellitus (T2DM) and cognitive dysfunction are highly prevalent disorders worldwide. Although visual network (VN) alteration and functional-structural coupling are potential warning factors for mild cognitive impairment (MCI) in T2DM patients, the relationship between the three in T2DM without MCI is unclear. Thirty T2DM patients without MCI and twenty-nine healthy controls (HC) were prospectively enrolled. Visual components (VC) were estimated by independent component analysis (ICA). Degree centrality (DC), amplitude of low frequency fluctuation (ALFF) and fractional anisotropy (FA) were established to reflect functional and structural characteristics in these VCs respectively. Functional-structural coupling coefficients were further evaluated using combined FA and DC or ALFF. Partial correlations were performed among neuroimaging indicators and neuropsychological scores and clinical variables. Three VCs were selected using group ICA. Deteriorated DC, ALFF and DC-FA coefficients in the VC1 were observed in the T2DM group compared with the HC group, while FA and ALFF-FA coefficients in these three VCs showed no significant differences. In the T2DM group, DC in the VC1 positively correlated with 2 dimensions in the California Verbal Learning Test, including Trial 4 and Total trial 1-5. The impaired DC-FA coefficients in the VC1 markedly affected the Total perseverative responses % of the Wisconsin Card Sorting Test. These findings indicate that DC and DC-FA coefficients in VN may be potential imaging biomarkers revealing early cognitive deficits in T2DM.
Collapse
Affiliation(s)
- Min-Hua Ni
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China
- Faculty of Medical Technology, Shaanxi University of Chinese Medicine, 1 Middle Section of Shiji Road, Xianyang, 712046, Shaanxi, China
| | - Ying Yu
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China
| | - Yang Yang
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China
| | - Ze-Yang Li
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China
| | - Teng Ma
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China
| | - Hao Xie
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China
| | - Si-Ning Li
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China
- Faculty of Medical Technology, Xi`an Medical University, 1 Xinwang Road, Xi'an, 710016, Shaanxi, China
| | - Pan Dai
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China
- Faculty of Medical Technology, Xi`an Medical University, 1 Xinwang Road, Xi'an, 710016, Shaanxi, China
| | - Xin-Yu Cao
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China
- Faculty of Medical Technology, Yan'an University, 580 Shengdi Road, Yan'an, 716000, Shaanxi, China
| | - Yan-Yan Cui
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China
- Faculty of Medical Technology, Shaanxi University of Chinese Medicine, 1 Middle Section of Shiji Road, Xianyang, 712046, Shaanxi, China
| | - Jun-Ling Zhu
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China
| | - Guang-Bin Cui
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China.
| | - Lin-Feng Yan
- Department of Radiology & Functional and Molecular Imaging Key Lab of Shaanxi Province, Tangdu Hospital, Fourth Military Medical University, 569 Xinsi Road, Xi'an, 710038, Shaanxi, China.
| |
Collapse
|
4
|
Feola AJ, Allen RS, Chesler KC, Pardue MT. Development of an Automated Electroretinography Analysis Approach. Transl Vis Sci Technol 2023; 12:14. [PMID: 37943551 PMCID: PMC10637214 DOI: 10.1167/tvst.12.11.14] [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: 06/22/2023] [Accepted: 10/09/2023] [Indexed: 11/10/2023] Open
Abstract
Purpose Electroretinography (ERG) is used to assess retinal function in ophthalmology clinics and animal models of ocular disease; however, analyzing ERG waveforms can be a time-intensive process with interobserver variability. We developed ERGAssist, an automated approach, to perform non-subjective and repeatable feature identification ("marking") of the ERG waveform. Methods The automated approach denoised the recorded waveforms and then located the b-wave after applying a lowpass filter. If an a-wave was present, the lowpass filter wave was also used to help locate the a-wave, which was considered the initial large negative response after the flash stimuli. Oscillatory potentials (OPs) were found using a bandpass filter on the denoised waveform. We used two cohorts. One was a Coherence cohort that consisted of ERGs with eight dark-adapted and three light-adapted stimuli in Brown Norway rats (-6 to 1.5 log cd·s/m2). The Verification cohort consisted of control and diabetic (DM) Long Evans rats. We examined retinal function using a five-step dark-adapted protocol (-3 to 1.9 log cd·s/m2). Results ERGAssist showed a strong correlation with manual markings of ERG features in our Coherence dataset, including the amplitudes (a-wave: r2 = 0.99; b-wave: r2 = 0.99; OP: r2 = 0.92) and implicit times (a-wave: r2 = 0.96; b-wave: r2 = 0.90; OP: r2 = 0.96). In the Verification cohort, both approaches detected differences between control and DM animals and found longer OP implicit times (P < 0.0001) in DM animals. Conclusions These results provide verification of ERGAssist to identify features of the full-field ERG. Translational Relevance This ERG analysis approach can increase the rigor of basic science studies designed to investigate retinal function using full-field ERG. To aid the community, we have developed an open-source graphical user interface (GUI) implementing the methods presented.
Collapse
Affiliation(s)
- Andrew J. Feola
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center, Atlanta, GA, USA
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, GA, USA
- Department of Ophthalmology, Emory Eye Center, Emory University School of Medicine, Atlanta, GA, USA
| | - Rachael S. Allen
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center, Atlanta, GA, USA
| | - Kyle C. Chesler
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center, Atlanta, GA, USA
| | - Machelle T. Pardue
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center, Atlanta, GA, USA
- Department of Biomedical Engineering, Georgia Institute of Technology/Emory University, Atlanta, GA, USA
- Department of Ophthalmology, Emory Eye Center, Emory University School of Medicine, Atlanta, GA, USA
| |
Collapse
|
5
|
Majimbi M, McLenachan S, Nesbit M, Chen FK, Lam V, Mamo J, Takechi R. In vivo retinal imaging is associated with cognitive decline, blood-brain barrier disruption and neuroinflammation in type 2 diabetic mice. Front Endocrinol (Lausanne) 2023; 14:1224418. [PMID: 37850093 PMCID: PMC10577437 DOI: 10.3389/fendo.2023.1224418] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 08/15/2023] [Indexed: 10/19/2023] Open
Abstract
Introduction Type 2 diabetes (T2D) is associated with chronic inflammation and neurovascular changes that lead to functional impairment and atrophy in neural-derived tissue. A reduction in retinal thickness is an early indicator of diabetic retinopathy (DR), with progressive loss of neuroglia corresponding to DR severity. The brain undergoes similar pathophysiological events as the retina, which contribute to T2D-related cognitive decline. Methods This study explored the relationship between retinal thinning and cognitive decline in the LepR db/db model of T2D. Diabetic db/db and non-diabetic db/+ mice aged 14 and 28 weeks underwent cognitive testing in short and long-term memory domains and in vivo retinal imaging using optical coherence tomography (OCT), followed by plasma metabolic measures and ex vivo quantification of neuroinflammation, oxidative stress and microvascular leakage. Results At 28 weeks, mice exhibited retinal thinning in the ganglion cell complex and inner nuclear layer, concomitant with diabetic insulin resistance, memory deficits, increased expression of inflammation markers and cerebrovascular leakage. Interestingly, alterations in retinal thickness at both experimental timepoints were correlated with cognitive decline and elevated immune response in the brain and retina. Discussion These results suggest that changes in retinal thickness quantified with in vivo OCT imaging may be an indicator of diabetic cognitive dysfunction and neuroinflammation.
Collapse
Affiliation(s)
- May Majimbi
- Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, Bentley, WA, Australia
| | - Samuel McLenachan
- Lions Eye Institute Australia, Harry Perkins Institute of Medical Research, Nedlands, WA, Australia
| | - Michael Nesbit
- Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, Bentley, WA, Australia
| | - Fred K. Chen
- Lions Eye Institute Australia, Harry Perkins Institute of Medical Research, Nedlands, WA, Australia
| | - Virginie Lam
- Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, Bentley, WA, Australia
| | - John Mamo
- Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, Bentley, WA, Australia
- Perron Institute for Neurological and Translational Research, Nedlands, WA, Australia
| | - Ryu Takechi
- Curtin Health Innovation Research Institute, Faculty of Health Sciences, Curtin University, Bentley, WA, Australia
| |
Collapse
|
6
|
Allen RS, Khayat CT, Feola AJ, Win AS, Grubman AR, Chesler KC, He L, Dixon JA, Kern TS, Iuvone PM, Thule PM, Pardue MT. Diabetic rats with high levels of endogenous dopamine do not show retinal vascular pathology. Front Neurosci 2023; 17:1125784. [PMID: 37034167 PMCID: PMC10073440 DOI: 10.3389/fnins.2023.1125784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 02/21/2023] [Indexed: 04/11/2023] Open
Abstract
Purpose Limited research exists on the time course of long-term retinal and cerebral deficits in diabetic rodents. Previously, we examined short term (4-8 weeks) deficits in the Goto-Kakizaki (GK) rat model of Type II diabetes. Here, we investigated the long-term (1-8 months) temporal appearance of functional deficits (retinal, cognitive, and motor), retinal vascular pathology, and retinal dopamine levels in the GK rat. Methods In GK rats and Wistar controls, retinal neuronal function (electroretinogram), cognitive function (Y-maze), and motor function (rotarod) were measured at 1, 2, 4, 6, and 8 months of age. In addition, we evaluated retinal vascular function (functional hyperemia) and glucose and insulin tolerance. Retinas from rats euthanized at ≥8 months were assessed for vascular pathology. Dopamine and DOPAC levels were measured via HPLC in retinas from rats euthanized at 1, 2, 8, and 12 months. Results Goto-Kakizaki rats exhibited significant glucose intolerance beginning at 4 weeks and worsening over time (p < 0.001). GK rats also showed significant delays in flicker and oscillatory potential implicit times (p < 0.05 to p < 0.001) beginning at 1 month. Cognitive deficits were observed beginning at 6 months (p < 0.05), but no motor deficits. GK rats showed no deficits in functional hyperemia and no increase in acellular retinal capillaries. Dopamine levels were twice as high in GK vs. Wistar retinas at 1, 2, 8, and 12 months (p < 0.001). Conclusion As shown previously, retinal deficits were detectable prior to cognitive deficits in GK rats. While retinal neuronal function was compromised, retinal vascular pathology was not observed, even at 12+ months. High endogenous levels of dopamine in the GK rat may be acting as an anti-angiogenic and providing protection against vascular pathology.
Collapse
Affiliation(s)
- Rachael S. Allen
- Atlanta VA Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, United States
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, United States
| | - Cara T. Khayat
- Atlanta VA Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, United States
| | - Andrew J. Feola
- Atlanta VA Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, United States
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, United States
- Department of Ophthalmology, Emory University, Atlanta, GA, United States
| | - Alice S. Win
- Atlanta VA Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, United States
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, United States
| | - Allison R. Grubman
- Atlanta VA Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, United States
- Department of Ophthalmology, Emory University, Atlanta, GA, United States
| | - Kyle C. Chesler
- Atlanta VA Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, United States
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, United States
| | - Li He
- Department of Ophthalmology, Emory University, Atlanta, GA, United States
- Department of Pharmacology and Chemical Biology, Emory University, Atlanta, GA, United States
| | - Jendayi A. Dixon
- Department of Ophthalmology, Emory University, Atlanta, GA, United States
| | - Timothy S. Kern
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH, United States
- Veterans Administration Medical Center Research Service, Cleveland, OH, United States
- Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA, United States
| | - P. Michael Iuvone
- Department of Ophthalmology, Emory University, Atlanta, GA, United States
- Department of Pharmacology and Chemical Biology, Emory University, Atlanta, GA, United States
| | - Peter M. Thule
- Section Endocrinology and Metabolism, Atlanta VA Medical Center, Emory University School of Medicine, Decatur, GA, United States
| | - Machelle T. Pardue
- Atlanta VA Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, United States
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, United States
- Department of Ophthalmology, Emory University, Atlanta, GA, United States
| |
Collapse
|
7
|
Damphousse CC, Medeiros JK, Micks NE, Marrone DF. Altered pattern separation in Goto-Kakizaki rats. CURRENT RESEARCH IN NEUROBIOLOGY 2023. [DOI: 10.1016/j.crneur.2023.100082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023] Open
|
8
|
Motor skills training-induced activation of descending pathways mediating cortical command to hindlimb motoneurons in experimental diabetic rats. Exp Neurol 2023; 363:114357. [PMID: 36849002 DOI: 10.1016/j.expneurol.2023.114357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2022] [Revised: 01/29/2023] [Accepted: 02/22/2023] [Indexed: 02/27/2023]
Abstract
Diabetes disrupts the corticospinal tract (CST) system components that control hindlimb and trunk movement, resulting in weakness of the lower extremities. However, there is no information about a method to improve these disorders. This study aimed to investigate the rehabilitative effects of 2 weeks of aerobic training (AT) and complex motor skills training (ST) on motor disorders in streptozotocin-induced type 1 diabetic rats. In this study, electrophysiological mapping of the motor cortex showed that the diabetes mellitus (DM)-ST group had a larger motor cortical area compared to the DM-AT group and sedentary diabetic animals. Moreover, hand grip strength and rotarod latency increased in the DM-ST group; however, these two parameters did not change in the DM-AT group, as well as in control and sedentary diabetic rats. Furthermore, in the DM-ST group, cortical stimulation-induced and motor-evoked potentials were preserved after the interception of the CST; however, this potential disappeared after additional lesions were made on lateral funiculus, suggesting that their function extends to activating motor descending pathways other than the CST locating lateral funiculus. According to immunohistochemical analysis, the larger fibers present on the dorsal part of the lateral funiculus, which corresponds to the rubrospinal tract of the DM-ST group, expressed the phosphorylated growth-associated protein, 43 kD, which is a specific marker of axons with plastic changes. Additionally, electrical stimulation of the red nucleus revealed expansion of the hindlimb-responsible area and increased motor-evoked potentials of the hindlimb in the DM-ST group, suggesting a strengthening of synaptic connections between the red nucleus and spinal interneurons driving motoneurons. These results reveal that ST induces plastic changes in the rubrospinal tract in a diabetic model, which can compensate for diabetes by disrupting the CST system components that control the hindlimb. This finding suggests that ST can be a novel rehabilitation strategy to improve motor dysfunctions in diabetic patients.
Collapse
|
9
|
Gonçalves JS, Seiça RM, Laranjinha J, Lourenço CF. Impairment of neurovascular coupling in the hippocampus due to decreased nitric oxide bioavailability supports early cognitive dysfunction in type 2 diabetic rats. Free Radic Biol Med 2022; 193:669-675. [PMID: 36372286 DOI: 10.1016/j.freeradbiomed.2022.11.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/01/2022] [Accepted: 11/07/2022] [Indexed: 11/13/2022]
Abstract
Numerous epidemiological and preclinical studies have established a strong correlation between type 2 diabetes (T2DM) and cognitive impairment and T2DM is now established as an undisputable risk factor in different forms of dementia. However, the mechanisms underlying cognitive impairment in T2DM are still not fully understood. The temporal and spatial coupling between neuronal activity and cerebral blood flow (CBF) - neurovascular coupling (NVC) - is essential for normal brain function. Neuronal-derived nitric oxide (⦁NO) produced through the nNOS-NMDAr pathway, is recognized as a key messenger in NVC, especially in the hippocampus. Of note, impaired hippocampal perfusion in T2DM patients has been closely linked to learning and memory dysfunction. In this study, we aimed to investigate the functionality of NVC, in terms of neuronal-•NO signaling and spatial memory performance, in young Goto-Kakizaki (GK) rats, a non-obese model of T2DM. For that, we performed direct and simultaneous measurements of •NO concentration dynamics and microvascular CBF changes in the hippocampus upon glutamatergic activation. We found that limited •NO bioavailability, connected to shorter and faster •NO transients in response to glutamatergic neuronal activation, is associated with decreased hemodynamic responses and a decline in spatial memory performance. This evidence supports a close mechanistic association between neuronal-triggered •NO concentration dynamics in the hippocampus, local microvascular responses, and cognitive performance in young diabetic animals, establishing the functionality of NVC as a critical early factor to consider in the cascade of events leading to cognitive decline in T2DM. These results suggest that strategies capable to overcome the limited •NO bioavailability in early stages of T2DM and maintaining a functional NVC pathway may configure pertinent therapeutic approaches to mitigate the risk for cognitive impairment in T2DM.
Collapse
Affiliation(s)
- João S Gonçalves
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal; Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal
| | - Raquel M Seiça
- Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - João Laranjinha
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal; Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal.
| | - Cátia F Lourenço
- Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal; Faculty of Pharmacy, University of Coimbra, Coimbra, Portugal.
| |
Collapse
|
10
|
Heather LC, Hafstad AD, Halade GV, Harmancey R, Mellor KM, Mishra PK, Mulvihill EE, Nabben M, Nakamura M, Rider OJ, Ruiz M, Wende AR, Ussher JR. Guidelines on Models of Diabetic Heart Disease. Am J Physiol Heart Circ Physiol 2022; 323:H176-H200. [PMID: 35657616 PMCID: PMC9273269 DOI: 10.1152/ajpheart.00058.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Diabetes is a major risk factor for cardiovascular diseases, including diabetic cardiomyopathy, atherosclerosis, myocardial infarction, and heart failure. As cardiovascular disease represents the number one cause of death in people with diabetes, there has been a major emphasis on understanding the mechanisms by which diabetes promotes cardiovascular disease, and how antidiabetic therapies impact diabetic heart disease. With a wide array of models to study diabetes (both type 1 and type 2), the field has made major progress in answering these questions. However, each model has its own inherent limitations. Therefore, the purpose of this guidelines document is to provide the field with information on which aspects of cardiovascular disease in the human diabetic population are most accurately reproduced by the available models. This review aims to emphasize the advantages and disadvantages of each model, and to highlight the practical challenges and technical considerations involved. We will review the preclinical animal models of diabetes (based on their method of induction), appraise models of diabetes-related atherosclerosis and heart failure, and discuss in vitro models of diabetic heart disease. These guidelines will allow researchers to select the appropriate model of diabetic heart disease, depending on the specific research question being addressed.
Collapse
Affiliation(s)
- Lisa C Heather
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Anne D Hafstad
- Department of Medical Biology, Faculty of Health Sciences, UiT-The Arctic University of Norway, Tromsø, Norway
| | - Ganesh V Halade
- Department of Medicine, The University of Alabama at Birmingham, Tampa, Florida, United States
| | - Romain Harmancey
- Department of Internal Medicine, Division of Cardiology, McGovern Medical School at The University of Texas Health Science Center at Houston, Houston, TX, United States
| | | | - Paras K Mishra
- Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE, United States
| | - Erin E Mulvihill
- University of Ottawa Heart Institute, Ottawa, ON, Canada.,Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Miranda Nabben
- Departments of Genetics and Cell Biology, and Clinical Genetics, Maastricht University Medical Center, CARIM School of Cardiovascular Diseases, Maastricht, the Netherlands
| | - Michinari Nakamura
- Department of Cell Biology and Molecular Medicine, Cardiovascular Research Institute, Rutgers New Jersey Medical School, Newark, NJ, United States
| | - Oliver J Rider
- University of Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Matthieu Ruiz
- Montreal Heart Institute, Montreal, Quebec, Canada.,Department of Nutrition, Université de Montréal, Montreal, Quebec, Canada
| | - Adam R Wende
- Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - John R Ussher
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada.,Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta, Canada.,Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| |
Collapse
|
11
|
Ciprés M, Satue M, Melchor I, Gil-Arribas L, Vilades E, Garcia-Martin E. Retinal neurodegeneration in patients with type 2 diabetes mellitus without diabetic retinopathy. ARCHIVOS DE LA SOCIEDAD ESPANOLA DE OFTALMOLOGIA 2022; 97:205-218. [PMID: 35523467 DOI: 10.1016/j.oftale.2022.02.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 04/06/2021] [Indexed: 06/14/2023]
Abstract
In diabetes mellitus (DM) patients retinal complications were typically considered part of a vascular process. Recent research suggests that retinal degeneration in DM might also be caused by a neuropathy that could precede microvascular alterations. The present work reviews the currently available bibliography about neurodegeneration in patients with type 2 DM (DM2) without diabetic retinopathy (DR). In patients with non-severe, early DM2 without DR and good metabolic control visual function parameters show early abnormalities that precede clinical DR (in which we diagnose with a conventional ophthalmological examination). Using optical coherence tomography (OCT) technology, a reduction in macular and peripapillary thickness has been observed in different studies. Recent researches suggest that systemic complications (especially ischaemia) and a possible microvascular alteration eventually contributes to retinal neurodegeneration, which opens the door to new studies that include new techniques for evaluating the microvascularization of the retinal layers.
Collapse
Affiliation(s)
- M Ciprés
- Servicio de Oftalmologia, Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain.
| | - M Satue
- Servicio de Oftalmología, Hospital Universitario Miguel Servet, Zaragoza, Grupo de investigación Miguel Servet Oftalmología (GIMSO), Instituto de Investigación Sanitaria de Aragón (IIS Aragón), Universidad de Zaragoza, Zaragoza, Spain
| | - I Melchor
- Departamento de Endocrinología, Hospital Universitario Miguel Servet, Zaragoza, Spain
| | - L Gil-Arribas
- Servicio de Oftalmología, Hospital Universitario Miguel Servet, Zaragoza, Grupo de investigación Miguel Servet Oftalmología (GIMSO), Instituto de Investigación Sanitaria de Aragón (IIS Aragón), Universidad de Zaragoza, Zaragoza, Spain
| | - E Vilades
- Servicio de Oftalmología, Hospital Universitario Miguel Servet, Zaragoza, Grupo de investigación Miguel Servet Oftalmología (GIMSO), Instituto de Investigación Sanitaria de Aragón (IIS Aragón), Universidad de Zaragoza, Zaragoza, Spain
| | - E Garcia-Martin
- Servicio de Oftalmología, Hospital Universitario Miguel Servet, Zaragoza, Grupo de investigación Miguel Servet Oftalmología (GIMSO), Instituto de Investigación Sanitaria de Aragón (IIS Aragón), Universidad de Zaragoza, Zaragoza, Spain
| |
Collapse
|
12
|
Podvigina TT, Yarushkina NI, Filaretova LP. Effects of Running on the Development of Diabetes and Diabetes-Induced Complications. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022010161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
13
|
Berdugo M, Delaunay K, Lebon C, Naud MC, Radet L, Zennaro L, Picard E, Daruich A, Beltrand J, Kermorvant-Duchemin E, Polak M, Crisanti P, Behar-Cohen FF. Long-Term Oral Treatment with Non-Hypoglycemic Dose of Glibenclamide Reduces Diabetic Retinopathy Damage in the Goto-KakizakiRat Model. Pharmaceutics 2021; 13:pharmaceutics13071095. [PMID: 34371786 PMCID: PMC8308933 DOI: 10.3390/pharmaceutics13071095] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/13/2021] [Accepted: 07/15/2021] [Indexed: 01/02/2023] Open
Abstract
Diabetic retinopathy (DR) remains a major cause of vision loss, due to macular edema, retinal ischemia and death of retinal neurons. We previously demonstrated that acute administration of glibenclamide into the vitreous, or given orally at a non-hypoglycemic dose, protected the structure and the function of the retina in three animal models that each mimic aspects of diabetic retinopathy in humans. In this pilot study, we investigated whether one year of chronic oral glibenclamide, in a non-hypoglycemic regimen (Amglidia®, 0.4 mg/kg, Ammtek/Nordic Pharma, 5 d/week), could alleviate the retinopathy that develops in the Goto-Kakizaki (GK) rat. In vivo, retinal function was assessed by electroretinography (ERG), retinal thickness by optical coherence tomography (OCT) and retinal perfusion by fluorescein and indocyanin green angiographies. The integrity of the retinal pigment epithelium (RPE) that constitutes the outer retinal barrier was evaluated by quantitative analysis of the RPE morphology on flat-mounted fundus ex vivo. Oral glibenclamide did not significantly reduce the Hb1Ac levels but still improved retinal function, as witnessed by the reduction in scotopic implicit times, limited diabetes-induced neuroretinal thickening and the extension of ischemic areas, and it improved the capillary coverage. These results indicate that low doses of oral glibenclamide could still be beneficial for the prevention of type 2 diabetic retinopathy. Whether the retinas ofpatients treated specifically with glibenclamideare less at risk of developing diabetic complications remains to be demonstrated.
Collapse
Affiliation(s)
- Marianne Berdugo
- Physiopathology of Ocular Diseases: Therapeutic Innovations, Sorbonne University and Universityof Paris, Inserm UMRS 1138, F-75006 Paris, France; (M.B.); (K.D.); (C.L.); (M.-C.N.); (L.R.); (L.Z.); (E.P.); (A.D.); (E.K.-D.); (P.C.)
| | - Kimberley Delaunay
- Physiopathology of Ocular Diseases: Therapeutic Innovations, Sorbonne University and Universityof Paris, Inserm UMRS 1138, F-75006 Paris, France; (M.B.); (K.D.); (C.L.); (M.-C.N.); (L.R.); (L.Z.); (E.P.); (A.D.); (E.K.-D.); (P.C.)
| | - Cécile Lebon
- Physiopathology of Ocular Diseases: Therapeutic Innovations, Sorbonne University and Universityof Paris, Inserm UMRS 1138, F-75006 Paris, France; (M.B.); (K.D.); (C.L.); (M.-C.N.); (L.R.); (L.Z.); (E.P.); (A.D.); (E.K.-D.); (P.C.)
| | - Marie-Christine Naud
- Physiopathology of Ocular Diseases: Therapeutic Innovations, Sorbonne University and Universityof Paris, Inserm UMRS 1138, F-75006 Paris, France; (M.B.); (K.D.); (C.L.); (M.-C.N.); (L.R.); (L.Z.); (E.P.); (A.D.); (E.K.-D.); (P.C.)
| | - Lolita Radet
- Physiopathology of Ocular Diseases: Therapeutic Innovations, Sorbonne University and Universityof Paris, Inserm UMRS 1138, F-75006 Paris, France; (M.B.); (K.D.); (C.L.); (M.-C.N.); (L.R.); (L.Z.); (E.P.); (A.D.); (E.K.-D.); (P.C.)
| | - Léa Zennaro
- Physiopathology of Ocular Diseases: Therapeutic Innovations, Sorbonne University and Universityof Paris, Inserm UMRS 1138, F-75006 Paris, France; (M.B.); (K.D.); (C.L.); (M.-C.N.); (L.R.); (L.Z.); (E.P.); (A.D.); (E.K.-D.); (P.C.)
| | - Emilie Picard
- Physiopathology of Ocular Diseases: Therapeutic Innovations, Sorbonne University and Universityof Paris, Inserm UMRS 1138, F-75006 Paris, France; (M.B.); (K.D.); (C.L.); (M.-C.N.); (L.R.); (L.Z.); (E.P.); (A.D.); (E.K.-D.); (P.C.)
| | - Alejandra Daruich
- Physiopathology of Ocular Diseases: Therapeutic Innovations, Sorbonne University and Universityof Paris, Inserm UMRS 1138, F-75006 Paris, France; (M.B.); (K.D.); (C.L.); (M.-C.N.); (L.R.); (L.Z.); (E.P.); (A.D.); (E.K.-D.); (P.C.)
- Department of Ophthalmology, AP-HP Hospital University Necker-Sick Children, F-75015 Paris, France
| | - Jacques Beltrand
- Department of Paediatric Endocrinology, Gynecology and Diabetology, AP-HP Hospital University Necker-Sick Children, F-75015 Paris, France; (J.B.); (M.P.)
- Faculté de Santé, University of Paris, F-75006 Paris, France
- Institut Cochin, InsermU1016, F-75005 Paris, France
| | - Elsa Kermorvant-Duchemin
- Physiopathology of Ocular Diseases: Therapeutic Innovations, Sorbonne University and Universityof Paris, Inserm UMRS 1138, F-75006 Paris, France; (M.B.); (K.D.); (C.L.); (M.-C.N.); (L.R.); (L.Z.); (E.P.); (A.D.); (E.K.-D.); (P.C.)
- Neonatal and Intensive Care Unit, AP-HP Hospital University Necker-Sick Children, F-75015 Paris, France
| | - Michel Polak
- Department of Paediatric Endocrinology, Gynecology and Diabetology, AP-HP Hospital University Necker-Sick Children, F-75015 Paris, France; (J.B.); (M.P.)
- Faculté de Santé, University of Paris, F-75006 Paris, France
- Institut Cochin, InsermU1016, F-75005 Paris, France
- Institute Imagine, InsermU1163, F-75015 Paris, France
| | - Patricia Crisanti
- Physiopathology of Ocular Diseases: Therapeutic Innovations, Sorbonne University and Universityof Paris, Inserm UMRS 1138, F-75006 Paris, France; (M.B.); (K.D.); (C.L.); (M.-C.N.); (L.R.); (L.Z.); (E.P.); (A.D.); (E.K.-D.); (P.C.)
| | - Francine F. Behar-Cohen
- Physiopathology of Ocular Diseases: Therapeutic Innovations, Sorbonne University and Universityof Paris, Inserm UMRS 1138, F-75006 Paris, France; (M.B.); (K.D.); (C.L.); (M.-C.N.); (L.R.); (L.Z.); (E.P.); (A.D.); (E.K.-D.); (P.C.)
- Ophthalmology, AP-HP Hospital Cochin, F-75005 Paris, France
- Correspondence:
| |
Collapse
|
14
|
Clarkson-Townsend DA, Bales KL, Marsit CJ, Pardue MT. Light Environment Influences Developmental Programming of the Metabolic and Visual Systems in Mice. Invest Ophthalmol Vis Sci 2021; 62:22. [PMID: 33861321 PMCID: PMC8083116 DOI: 10.1167/iovs.62.4.22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 03/27/2021] [Indexed: 02/06/2023] Open
Abstract
Purpose Light is a salient cue that can influence neurodevelopment and the immune system. Light exposure out of sync with the endogenous clock causes circadian disruption and chronic disease. Environmental light exposure may contribute to developmental programming of metabolic and neurological systems but has been largely overlooked in Developmental Origins of Health and Disease (DOHaD) research. Here, we investigated whether developmental light exposure altered programming of visual and metabolic systems. Methods Pregnant mice and pups were exposed to control light (12:12 light:dark) or weekly light cycle inversions (circadian disruption [CD]) until weaning, after which male and female offspring were housed in control light and longitudinally measured to evaluate differences in growth (weight), glucose tolerance, visual function (optomotor response), and retinal function (electroretinogram), with and without high fat diet (HFD) challenge. Retinal microglia and macrophages were quantified by positive Iba1 and CD11b immunofluorescence. Results CD exposure caused impaired visual function and increased retinal immune cell expression in adult offspring. When challenged with HFD, CD offspring also exhibited altered retinal function and sex-specific impairments in glucose tolerance. Conclusions Overall, these findings suggest that the light environment contributes to developmental programming of the metabolic and visual systems, potentially promoting a pro-inflammatory milieu in the retina and increasing the risk of visual disease later in life.
Collapse
Affiliation(s)
- Danielle A. Clarkson-Townsend
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, Georgia, United States
| | - Katie L. Bales
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, Georgia, United States
- Department of Ophthalmology, Emory University, Atlanta, Georgia, United States
| | - Carmen J. Marsit
- Gangarosa Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, United States
| | - Machelle T. Pardue
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, Georgia, United States
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia, United States
| |
Collapse
|
15
|
Chesler K, Motz C, Vo H, Douglass A, Allen RS, Feola AJ, Pardue MT. Initiation of L-DOPA Treatment After Detection of Diabetes-Induced Retinal Dysfunction Reverses Retinopathy and Provides Neuroprotection in Rats. Transl Vis Sci Technol 2021; 10:8. [PMID: 34003986 PMCID: PMC8054623 DOI: 10.1167/tvst.10.4.8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Purpose L-DOPA treatment initiated at the start of hyperglycemia preserves retinal and visual function in diabetic rats. Here, we investigated a more clinically relevant treatment strategy in which retinal and visual dysfunction designated the beginning of the therapeutic window for L-DOPA treatment. Methods Spatial frequency thresholds using optomotor response and oscillatory potential (OP) delays using electroretinograms were compared at baseline, 3, 6, and 10 weeks after streptozotocin (STZ) between diabetic and control rats. L-DOPA/carbidopa treatment (DOPA) or vehicle was delivered orally 5 days per week beginning at 3 weeks after STZ, when significant retinal and visual deficits were measured. At 10 weeks after STZ, retinas were collected to measure L-DOPA, dopamine, and 3,4-dihydroxyphenylacetic acid (DOPAC) levels using high-performance liquid chromatography. Results Spatial frequency thresholds decreased at 6 weeks in diabetic vehicle rats (28%), whereas diabetic DOPA rats had stable thresholds (<1%) that maintained to 10 weeks, creating significantly higher thresholds compared with diabetic vehicle rats (P < 0.0001). OP2 implicit times in response to dim, rod-driven stimuli were decreased in diabetic compared with control rats (3 weeks, P < 0.0001; 10 weeks, P < 0.01). With L-DOPA treatment, OP2 implicit times recovered in diabetic rats to be indistinguishable from control rats by 10 weeks after STZ. Rats treated with L-DOPA showed significantly increased retinal L-DOPA (P < 0.001) and dopamine levels (P < 0.05). Conclusions L-DOPA treatment started after the detection of retinal and visual dysfunction showed protective effects in diabetic rats. Translational Relevance Early retinal functional deficits induced by diabetes can be used to identify an earlier therapeutic window for L-DOPA treatment which protects from further vision loss and restores retinal function.
Collapse
Affiliation(s)
- Kyle Chesler
- Atlanta VA Healthcare System, Atlanta, GA, USA.,Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Cara Motz
- Atlanta VA Healthcare System, Atlanta, GA, USA.,Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Harrison Vo
- Atlanta VA Healthcare System, Atlanta, GA, USA
| | | | - Rachael S Allen
- Atlanta VA Healthcare System, Atlanta, GA, USA.,Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Andrew J Feola
- Atlanta VA Healthcare System, Atlanta, GA, USA.,Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Machelle T Pardue
- Atlanta VA Healthcare System, Atlanta, GA, USA.,Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| |
Collapse
|
16
|
Prehabilitative exercise hastens recovery from isoflurane in diabetic and non-diabetic rats. Neurosci Lett 2021; 751:135808. [PMID: 33705936 DOI: 10.1016/j.neulet.2021.135808] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 02/06/2021] [Accepted: 03/02/2021] [Indexed: 01/18/2023]
Abstract
Diabetes has been demonstrated to be one of the strongest predictors of risk for postoperative delirium and functional decline in older patients undergoing surgery. Exercise is often prescribed as a treatment for diabetic patients and regular physical activity is hypothesized to decrease the risk of postoperative cognitive impairments. Prior studies suggest that anesthetic emergence trajectories and recovery are predictive of risk for later postoperative cognitive impairments. Therapeutic strategies aimed at improving emergence and recovery from anesthesia may therefore be beneficial for diabetic patients. Wistar (n = 32) and Goto-Kakizaki (GK) type 2 diabetic (n = 32) rats between 3-4 months old underwent treadmill exercise for 30 min/day for ten days or remained inactive. Pre-anesthesia spontaneous alternation behavior was recorded with a Y-maze. Rats then received a 2-h exposure to 1.5-2 % isoflurane or oxygen only. The time to reach anesthetic emergence and post-anesthesia recovery behaviors was recorded for each rat. Postsynaptic density protein-95 (PSD-95), an important scaffolding protein required for synaptic plasticity, protein levels were quantified from hippocampus using western blot. Spontaneous alternation behavior (p = 0.044) and arm entries (p < 0.001) were decreased in GK rats. There was no difference between groups in emergence times from isoflurane, but exercise hastened the recovery time (p = 0.008) for both Wistar and GK rats. Following 10 days of exercise, both Wistar and GK rats show increased levels of PSD-95 in the hippocampus. Prehabilitation with moderate intensity exercise, even on a short timescale, is beneficial for recovery from isoflurane in rats, regardless of metabolic disease status.
Collapse
|
17
|
Clarkson-Townsend DA, Douglass AJ, Singh A, Allen RS, Uwaifo IN, Pardue MT. Impacts of high fat diet on ocular outcomes in rodent models of visual disease. Exp Eye Res 2021; 204:108440. [PMID: 33444582 PMCID: PMC7946735 DOI: 10.1016/j.exer.2021.108440] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 12/23/2020] [Accepted: 01/05/2021] [Indexed: 02/08/2023]
Abstract
High fat diets (HFD) have been utilized in rodent models of visual disease for over 50 years to model the effects of lipids, metabolic dysfunction, and diet-induced obesity on vision and ocular health. HFD treatment can recapitulate the pathologies of some of the leading causes of blindness, such as age-related macular degeneration (AMD) and diabetic retinopathy (DR) in rodent models of visual disease. However, there are many important factors to consider when using and interpreting these models. To synthesize our current understanding of the importance of lipid signaling, metabolism, and inflammation in HFD-driven visual disease processes, we systematically review the use of HFD in mouse and rat models of visual disease. The resulting literature is grouped into three clusters: models that solely focus on HFD treatment, models of diabetes that utilize both HFD and streptozotocin (STZ), and models of AMD that utilize both HFD and genetic models and/or other exposures. Our findings show that HFD profoundly affects vision, retinal function, many different ocular tissues, and multiple cell types through a variety of mechanisms. We delineate how HFD affects the cornea, lens, uvea, vitreous humor, retina, retinal pigmented epithelium (RPE), and Bruch's membrane (BM). Furthermore, we highlight how HFD impairs several retinal cell types, including glia (microglia), retinal ganglion cells, bipolar cells, photoreceptors, and vascular support cells (endothelial cells and pericytes). However, there are a number of gaps, limitations, and biases in the current literature. We highlight these gaps and discuss experimental design to help guide future studies. Very little is known about how HFD impacts the lens, ciliary bodies, and specific neuronal populations, such as rods, cones, bipolar cells, amacrine cells, and retinal ganglion cells. Additionally, sex bias is an important limitation in the current literature, with few HFD studies utilizing female rodents. Future studies should use ingredient-matched control diets (IMCD), include both sexes in experiments to evaluate sex-specific outcomes, conduct longitudinal metabolic and visual measurements, and capture acute outcomes. In conclusion, HFD is a systemic exposure with profound systemic effects, and rodent models are invaluable in understanding the impacts on visual and ocular disease.
Collapse
Affiliation(s)
- Danielle A Clarkson-Townsend
- Gangarosa Department of Environmental Health, Emory University, Atlanta, GA, USA; Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, USA
| | - Amber J Douglass
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, USA
| | - Anayesha Singh
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, USA; Emory Center for Ethics, Emory University, Atlanta, GA, USA
| | - Rachael S Allen
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, USA; Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Ivie N Uwaifo
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, USA; Department of Neuroscience, Emory University, Atlanta, GA, USA
| | - Machelle T Pardue
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Decatur, GA, USA; Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA.
| |
Collapse
|
18
|
Dastgheyb RM, Buchholz AS, Fitzgerald KC, Xu Y, Williams DW, Springer G, Anastos K, Gustafson DR, Spence AB, Adimora AA, Waldrop D, Vance DE, Milam J, Bolivar H, Weber KM, Haughey NJ, Maki PM, Rubin LH. Patterns and Predictors of Cognitive Function Among Virally Suppressed Women With HIV. Front Neurol 2021; 12:604984. [PMID: 33679577 PMCID: PMC7928382 DOI: 10.3389/fneur.2021.604984] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 01/18/2021] [Indexed: 11/13/2022] Open
Abstract
Cognitive impairment remains frequent and heterogeneous in presentation and severity among virally suppressed (VS) women with HIV (WWH). We identified cognitive profiles among 929 VS-WWH and 717 HIV-uninfected women from 11 Women's Interagency HIV Study sites at their first neuropsychological (NP) test battery completion comprised of: Hopkins Verbal Learning Test-Revised, Trail Making, Symbol Digit Modalities, Grooved Pegboard, Stroop, Letter/Animal Fluency, and Letter-Number Sequencing. Using 17 NP performance metrics (T-scores), we used Kohonen self-organizing maps to identify patterns of high-dimensional data by mapping participants to similar nodes based on T-scores and clustering those nodes. Among VS-WWH, nine clusters were identified (entropy = 0.990) with four having average T-scores ≥45 for all metrics and thus combined into an "unimpaired" profile (n = 311). Impaired profiles consisted of weaknesses in: (1) sequencing (Profile-1; n = 129), (2) speed (Profile-2; n = 144), (3) learning + recognition (Profile-3; n = 137), (4) learning + memory (Profile-4; n = 86), and (5) learning + processing speed + attention + executive function (Profile-5; n = 122). Sociodemographic, behavioral, and clinical variables differentiated profile membership using Random Forest models. The top 10 variables distinguishing the combined impaired vs. unimpaired profiles were: clinic site, age, education, race, illicit substance use, current and nadir CD4 count, duration of effective antiretrovirals, and protease inhibitor use. Additional variables differentiating each impaired from unimpaired profile included: depression, stress-symptoms, income (Profile-1); depression, employment (Profile 2); depression, integrase inhibitor (INSTI) use (Profile-3); employment, INSTI use, income, atazanavir use, non-ART medications with anticholinergic properties (Profile-4); and marijuana use (Profile-5). Findings highlight consideration of NP profile heterogeneity and potential modifiable factors contributing to impaired profiles.
Collapse
Affiliation(s)
- Raha M. Dastgheyb
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Alison S. Buchholz
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Kathryn C. Fitzgerald
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Yanxun Xu
- Department of Applied Mathematics and Statistics, Johns Hopkins University, Baltimore, MD, United States
- Division of Biostatistics and Bioinformatics, The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Dionna W. Williams
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Division of Clinical Pharmacology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Gayle Springer
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| | - Kathryn Anastos
- Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Deborah R. Gustafson
- Department of Neurology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States
| | - Amanda B. Spence
- Division of Infectious Disease and Travel Medicine, Department of Medicine, Georgetown University, Washington, DC, United States
| | - Adaora A. Adimora
- Division of Infectious Diseases, Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Drenna Waldrop
- Nell Hodgson Woodruff School of Nursing, Emory University, Atlanta, GA, United States
| | - David E. Vance
- School of Nursing, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Joel Milam
- Institute for Health Promotion & Disease Prevention Research, University of Southern California, Los Angeles, CA, United States
| | - Hector Bolivar
- Department of Psychiatry & Behavioral Science, University of Miami Miller School of Medicine, Miami, FL, United States
| | - Kathleen M. Weber
- CORE Center, Cook County Health, Hektoen Institute of Medicine, Chicago, IL, United States
| | - Norman J. Haughey
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Pauline M. Maki
- Department of Psychiatry and Psychology, University of Illinois at Chicago, Chicago, IL, United States
| | - Leah H. Rubin
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, United States
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, United States
| |
Collapse
|
19
|
Yang Y, Liu Y, Li Y, Chen Z, Xiong Y, Zhou T, Tao W, Xu F, Yang H, Ylä-Herttuala S, Chaurasia SS, Adam WC, Yang K. MicroRNA-15b Targets VEGF and Inhibits Angiogenesis in Proliferative Diabetic Retinopathy. J Clin Endocrinol Metab 2020; 105:5892806. [PMID: 32797181 PMCID: PMC7947967 DOI: 10.1210/clinem/dgaa538] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 08/11/2020] [Indexed: 12/21/2022]
Abstract
BACKGROUND Vascular endothelial growth factor (VEGF)-induced angiogenesis is a critical compensatory response to microvascular rarefaction in the diabetic retina that contributes to proliferative diabetic retinopathy (PDR). In this study, we sought to determine the role of specific micro ribonucleic acids (RNAs) (miRs) associated with VEGF in patients with PDR pathology. METHODS RNA sequencing was employed to detect differentially circulating miR associated with VEGF in patients with diabetes mellitus (DM), nonproliferative diabetic retinopathy (NPDR) and PDR. Quantitative real-time polymerase chain reaction was performed to measure the concentration of miR-15b in the serum of patients with DM (n = 115), NPDR (n = 47), or PDR (n = 76). The effects of miR-15b on DR and regulation of VEGF and endothelial cell function were also characterized. RESULTS We demonstrated that circulating miR-15b was directly associated with VEGF compared with other miRs in patients with PDR. We found a significant inverse relationship between low levels of miR-15b and high levels of VEGF in patients with PDR when compared with the DM or NPDR groups. We found that miR-15b regulates the expression of VEGF by targeting the 3'-untranslated regions to inhibit its transcription. Similarly, overexpression of miR-15b suppressed vascular abnormalities in vivo in diabetic GK rats, inhibiting endothelial tube formation and VEGF expression. CONCLUSION Circulating miR-15b is associated with PDR and may be targeted to regulate VEGF expression and angiogenesis.
Collapse
Affiliation(s)
- Ying Yang
- Department of Endocrinology, The Second People’s Hospital of Yunnan Province, Kunming, Yunnan, China
| | - Yan Liu
- Department of Cardiology, Shanghai Ninth People’s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yiping Li
- Department of Endocrinology, The Second People’s Hospital of Yunnan Province, Kunming, Yunnan, China
| | - Zhongli Chen
- Institute of Cardiovascular Disease, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yixin Xiong
- Department of Endocrinology, The Second People’s Hospital of Yunnan Province, Kunming, Yunnan, China
| | - Taicheng Zhou
- Department of Endocrinology, The Second People’s Hospital of Yunnan Province, Kunming, Yunnan, China
| | - Wenyu Tao
- Department of Endocrinology, The Second People’s Hospital of Yunnan Province, Kunming, Yunnan, China
| | - Fan Xu
- Department of Endocrinology, The Second People’s Hospital of Yunnan Province, Kunming, Yunnan, China
| | - Hanling Yang
- Department of Endocrinology, The Second People’s Hospital of Yunnan Province, Kunming, Yunnan, China
| | - Seppo Ylä-Herttuala
- Department of Biotechnology and Molecular Medicine, A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio; and Heart Center and Gene Therapy Unit, Kuopio University Hospital, Finland
| | - Shyam S Chaurasia
- Ocular Immunology and Angiogenesis Lab, University of Missouri, Columbia, Missouri
| | - Whaley-Connell Adam
- Division of Endocrinology and Metabolism, Department of Medicine, University of Missouri, Columbia, Missouri
- Research Service, Harry S. Truman Memorial Veterans’ Hospital, Columbia, Missouri
- Division of Nephrology, Department of Medicine, University of Missouri, Columbia, Missouri
- Correspondence and Reprint Requests: Ke Yang, PhD, Institute of Cardiovascular Disease, Rui Jin Hospital, Shanghai Jiaotong University School of Medicine, 197 Rui Jin Road II, Shanghai 200025, People’s Republic of China. E-mail: ; Adam T. Whaley-Connell, DO, MSPH, MEd, Harry S Truman Memorial Veterans Hospital, Division of Nephrology and Hypertension, University of Missouri-Columbia School of Medicine, 4903 Durham Chase, Columbia, MO 65203, USA. E-mail:
| | - Ke Yang
- Institute of Cardiovascular Disease, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
- Correspondence and Reprint Requests: Ke Yang, PhD, Institute of Cardiovascular Disease, Rui Jin Hospital, Shanghai Jiaotong University School of Medicine, 197 Rui Jin Road II, Shanghai 200025, People’s Republic of China. E-mail: ; Adam T. Whaley-Connell, DO, MSPH, MEd, Harry S Truman Memorial Veterans Hospital, Division of Nephrology and Hypertension, University of Missouri-Columbia School of Medicine, 4903 Durham Chase, Columbia, MO 65203, USA. E-mail:
| |
Collapse
|
20
|
Allen RS, Douglass A, Vo H, Feola AJ. Ovariectomy worsens visual function after mild optic nerve crush in rodents. Exp Eye Res 2020; 202:108333. [PMID: 33129829 DOI: 10.1016/j.exer.2020.108333] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 10/16/2020] [Accepted: 10/22/2020] [Indexed: 11/30/2022]
Abstract
Glaucoma is the leading cause of irreversible blindness worldwide, and women represent roughly 60% of the affected population. Early menopause and estrogen signaling defects are risk factors for glaucoma. Recently, we found that surgical menopause exacerbated visual dysfunction in an ocular hypertension model of glaucoma. Here, we investigated if surgical menopause exacerbated visual dysfunction in a model of direct retinal ganglion cell (RGC) damage via optic nerve crush (ONC). Female Long Evans rats (n = 12) underwent ovariectomy (OVX) to induce surgical menopause or Sham surgery. Eight weeks post-surgery, baseline visual function was assessed via optomotor response. Afterwards, rats underwent monocular ONC. Visual function was assessed at 4, 8, and 12 weeks post-ONC. At 12 weeks, retinal function via electroretinography and retinal nerve fiber layer (RNFL) thickness via optical coherence tomography were measured. Visual acuity was reduced after ONC (p < 0.001), with surgical menopausal animals having 31.7% lower visual acuity than Sham animals at 12 weeks (p = 0.01). RNFL thinning (p < 0.0001) and decreased RGC function (p = 0.0016) occurred at 12 weeks in ONC groups. Surgical menopause worsens visual acuity after direct RGC damage using an ONC model. This demonstrates that surgical menopause plays a role in visual function after injury.
Collapse
Affiliation(s)
- Rachael S Allen
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Atlanta, GA, USA; Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Amber Douglass
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Atlanta, GA, USA
| | - Harrison Vo
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Atlanta, GA, USA
| | - Andrew J Feola
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Healthcare System, Atlanta, GA, USA; Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA.
| |
Collapse
|
21
|
Gudapati K, Singh A, Clarkson-Townsend D, Feola AJ, Allen RS. Behavioral Assessment of Visual Function via Optomotor Response and Cognitive Function via Y-Maze in Diabetic Rats. J Vis Exp 2020. [PMID: 33165321 DOI: 10.3791/61806] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The optomotor response and the Y-maze are behavioral tests useful for assessing visual and cognitive function, respectively. The optomotor response is a valuable tool to track changes in spatial frequency (SF) and contrast sensitivity (CS) thresholds over time in a number of retinal disease models, including diabetic retinopathy. Similarly, the Y-maze can be used to monitor spatial cognition (as measured by spontaneous alternation) and exploratory behavior (as measured by a number of entries) in a number of disease models that affect the central nervous system. Advantages of the optomotor response and the Y-maze include sensitivity, speed of testing, the use of innate responses (training is not needed), and the ability to be performed on awake (non-anesthetized) animals. Here, protocols are described for both the optomotor response and the Y-maze and examples of their use shown in models of Type I and Type II diabetes. Methods include preparation of rodents and equipment, performance of the optomotor response and the Y-maze, and post-test data analysis.
Collapse
Affiliation(s)
- Kaavya Gudapati
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center; Department of Biomedical Engineering, Georgia Institute of Technology
| | - Anayesha Singh
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center; Department of Neuroscience, Emory University
| | - Danielle Clarkson-Townsend
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center; Gangarosa Department of Environmental Health, Emory University
| | - Andrew J Feola
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center; Department of Biomedical Engineering, Georgia Institute of Technology
| | - Rachael S Allen
- Center for Visual and Neurocognitive Rehabilitation, Atlanta VA Medical Center; Department of Biomedical Engineering, Georgia Institute of Technology;
| |
Collapse
|
22
|
Allen RS, Bales K, Feola A, Pardue MT. In vivo Structural Assessments of Ocular Disease in Rodent Models using Optical Coherence Tomography. J Vis Exp 2020. [PMID: 32773758 DOI: 10.3791/61588] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Spectral-domain optical coherence tomography (SD-OCT) is useful for visualizing retinal and ocular structures in vivo. In research, SD-OCT is a valuable tool to evaluate and characterize changes in a variety of retinal and ocular disease and injury models. In light induced retinal degeneration models, SD-OCT can be used to track thinning of the photoreceptor layer over time. In glaucoma models, SD-OCT can be used to monitor decreased retinal nerve fiber layer and total retinal thickness and to observe optic nerve cupping after inducing ocular hypertension. In diabetic rodents, SD-OCT has helped researchers observe decreased total retinal thickness as well as decreased thickness of specific retinal layers, particularly the retinal nerve fiber layer with disease progression. In mouse models of myopia, SD-OCT can be used to evaluate axial parameters, such as axial length changes. Advantages of SD-OCT include in vivo imaging of ocular structures, the ability to quantitatively track changes in ocular dimensions over time, and its rapid scanning speed and high resolution. Here, we detail the methods of SD-OCT and show examples of its use in our laboratory in models of retinal degeneration, glaucoma, diabetic retinopathy, and myopia. Methods include anesthesia, SD-OCT imaging, and processing of the images for thickness measurements.
Collapse
Affiliation(s)
- Rachael S Allen
- Center of Excellence for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center; Department of Biomedical Engineering, Georgia Institute of Technology;
| | - Katie Bales
- Center of Excellence for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center; Department of Ophthalmology, Emory University
| | - Andrew Feola
- Center of Excellence for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center; Department of Biomedical Engineering, Georgia Institute of Technology
| | - Machelle T Pardue
- Center of Excellence for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center; Department of Biomedical Engineering, Georgia Institute of Technology; Department of Ophthalmology, Emory University
| |
Collapse
|
23
|
Motz CT, Chesler KC, Allen RS, Bales KL, Mees LM, Feola AJ, Maa AY, Olson DE, Thule PM, Iuvone PM, Hendrick AM, Pardue MT. Novel Detection and Restorative Levodopa Treatment for Preclinical Diabetic Retinopathy. Diabetes 2020; 69:1518-1527. [PMID: 32051147 PMCID: PMC7306127 DOI: 10.2337/db19-0869] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 02/09/2020] [Indexed: 12/21/2022]
Abstract
Diabetic retinopathy (DR) is diagnosed clinically by directly viewing retinal vascular changes during ophthalmoscopy or through fundus photographs. However, electroretinography (ERG) studies in humans and rodents have revealed that retinal dysfunction is demonstrable prior to the development of visible vascular defects. Specifically, delays in dark-adapted ERG oscillatory potential (OP) implicit times in response to dim-flash stimuli (<-1.8 log cd · s/m2) occur prior to clinically recognized DR. Animal studies suggest that retinal dopamine deficiency underlies these early functional deficits. In this study, we randomized individuals with diabetes, without clinically detectable retinopathy, to treatment with either low- or high-dose Sinemet (levodopa plus carbidopa) for 2 weeks and compared their ERG findings with those of control subjects (no diabetes). We assessed dim-flash-stimulated OP delays using a novel handheld ERG system (RETeval) at baseline and 2 and 4 weeks. RETeval recordings identified significant OP implicit time delays in individuals with diabetes without retinopathy compared with age-matched control subjects (P < 0.001). After 2 weeks of Sinemet treatment, OP implicit times were restored to control values, and these improvements persisted even after a 2-week washout. We conclude that detection of dim-flash OP delays could provide early detection of DR and that Sinemet treatment may reverse retinal dysfunction.
Collapse
Affiliation(s)
- Cara T Motz
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center, Decatur, GA
| | - Kyle C Chesler
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center, Decatur, GA
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA
| | - Rachael S Allen
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center, Decatur, GA
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA
| | - Katie L Bales
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center, Decatur, GA
- Department of Ophthalmology, Emory University, Atlanta, GA
| | - Lukas M Mees
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center, Decatur, GA
| | - Andrew J Feola
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center, Decatur, GA
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA
| | - April Y Maa
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center, Decatur, GA
- Department of Ophthalmology, Emory University, Atlanta, GA
| | - Darin E Olson
- Division of Endocrinology, Metabolism and Lipids, Emory University, Atlanta, GA
- Medical Service, Atlanta Veterans Affairs Medical Center, Decatur, GA
| | - Peter M Thule
- Division of Endocrinology, Metabolism and Lipids, Emory University, Atlanta, GA
- Medical Service, Atlanta Veterans Affairs Medical Center, Decatur, GA
| | - P Michael Iuvone
- Department of Ophthalmology, Emory University, Atlanta, GA
- Department of Pharmacology and Chemical Biology, Emory University, Atlanta, GA
| | | | - Machelle T Pardue
- Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affairs Medical Center, Decatur, GA
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA
- Department of Ophthalmology, Emory University, Atlanta, GA
| |
Collapse
|