1
|
Eggers ED. Visual Dysfunction in Diabetes. Annu Rev Vis Sci 2023; 9:91-109. [PMID: 37164027 DOI: 10.1146/annurev-vision-111022-123810] [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] [Indexed: 05/12/2023]
Abstract
Although diabetic retinopathy (DR) is clinically diagnosed as a vascular disease, many studies find retinal neuronal and visual dysfunction before the onset of vascular DR. This suggests that DR should be viewed as a neurovascular disease. Prior to the onset of DR, human patients have compromised electroretinograms that indicate a disruption of normal function, particularly in the inner retina. They also exhibit reduced contrast sensitivity. These early changes, especially those due to dysfunction in the inner retina, are also seen in rodent models of diabetes in the early stages of the disease. Rodent models of diabetes exhibit several neuronal mechanisms, such as reduced evoked GABA release, increased excitatory glutamate signaling, and reduced dopamine signaling, that suggest specific neuronal deficits. This suggests that understanding neuronal deficits may lead to early diabetes treatments to ameliorate neuronal dysfunction.
Collapse
Affiliation(s)
- Erika D Eggers
- Departments of Physiology and Biomedical Engineering, University of Arizona, Tucson, Arizona, USA;
| |
Collapse
|
2
|
Parravano M, Ziccardi L, Borrelli E, Costanzo E, Frontoni S, Picconi F, Parisi V, Sacconi R, Di Renzo A, Varano M, Querques G. Outer retina dysfunction and choriocapillaris impairment in type 1 diabetes. Sci Rep 2021; 11:15183. [PMID: 34312425 PMCID: PMC8313686 DOI: 10.1038/s41598-021-94580-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 06/28/2021] [Indexed: 12/15/2022] Open
Abstract
To study the outer retina morpho-functional characteristics and the choriocapillaris (CC) features in type 1 diabetic (T1D) patients, with and without signs of diabetic retinopathy (NPDR and NoDR). Twenty-five NPDR and 18 NoDR eyes were imaged by Optical Coherence Tomography Angiography. Ellipsoid zone (EZ) “normalized” reflectivity and CC perfusion density parameters, as flow deficits number (FDn), flow deficit average area (FDa) and flow deficit percentage (FD%), were analysed. Multifocal electroretinogram (mfERG) response amplitude densities (RADs) were measured. Mean EZ “normalized” reflectivity, CC FDn and FD% values, were similar (p > 0.05) in both groups, FDa was significant greater (p > 0.05) in NPDR compared with NoDR eyes. MfERG-RADs were similar in both groups. NPDR eyes showed a significant (p < 0.05) linear correlation between RADs and both, CC FDa and FD%. The EZ “normalized” reflectivity was negatively correlated with CC FD% in NoDR eyes. In NPDR T1D eyes a significant relationship between abnormal outer retina functional responses and CC impairment was observed, while in NoDR eyes the photoreceptor reflectivity was correlated to CC abnormalities. The outer retina dysfunction in NPDR correlated to CC drop-out let hypothesize that the outer retinal elements are functionally impaired in proportion to the CC vascular supply deficit.
Collapse
Affiliation(s)
| | | | - E Borrelli
- Department of Ophthalmology, IRCCS Ospedale San Raffaele, University Vita-Salute, Via Olgettina, 60, Milan, Italy
| | | | - S Frontoni
- Unit of Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita Fatebenefratelli Hospital, Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - F Picconi
- Unit of Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita Fatebenefratelli Hospital, Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - V Parisi
- IRCCS - Fondazione Bietti, Rome, Italy
| | - R Sacconi
- Department of Ophthalmology, IRCCS Ospedale San Raffaele, University Vita-Salute, Via Olgettina, 60, Milan, Italy
| | | | - M Varano
- IRCCS - Fondazione Bietti, Rome, Italy
| | - G Querques
- Department of Ophthalmology, IRCCS Ospedale San Raffaele, University Vita-Salute, Via Olgettina, 60, Milan, Italy.
| |
Collapse
|
3
|
Abstract
Diabetic retinopathy is now well understood as a neurovascular disease. Significant deficits early in diabetes are found in the inner retina that consists of bipolar cells that receive inputs from rod and cone photoreceptors, ganglion cells that receive inputs from bipolar cells, and amacrine cells that modulate these connections. These functional deficits can be measured in vivo in diabetic humans and animal models using the electroretinogram (ERG) and behavioral visual testing. Early effects of diabetes on both the human and animal model ERGs are changes to the oscillatory potentials that suggest dysfunctional communication between amacrine cells and bipolar cells as well as ERG measures that suggest ganglion cell dysfunction. These are coupled with changes in contrast sensitivity that suggest inner retinal changes. Mechanistic in vitro neuronal studies have suggested that these inner retinal changes are due to decreased inhibition in the retina, potentially due to decreased gamma aminobutyric acid (GABA) release, increased glutamate release, and increased excitation of retinal ganglion cells. Inner retinal deficits in dopamine levels have also been observed that can be reversed to limit inner retinal damage. Inner retinal targets present a promising new avenue for therapies for early-stage diabetic eye disease.
Collapse
|
4
|
Ziccardi L, Parisi V, Picconi F, Di Renzo A, Lombardo M, Frontoni S, Parravano M. Early and localized retinal dysfunction in patients with type 1 diabetes mellitus studied by multifocal electroretinogram. Acta Diabetol 2018; 55:1191-1200. [PMID: 30159747 DOI: 10.1007/s00592-018-1209-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 08/06/2018] [Indexed: 02/02/2023]
Abstract
AIMS To investigate the function of localized retinal areas in highly selected type 1 diabetes mellitus patients (DM1) with no or mild signs of diabetic retinopathy (NO DR and NPDR, respectively) and its correlation with age, diabetes duration and glycemic control. METHODS Multifocal electroretinograms (mfERG) were recorded in 35 eyes of 18 NO DR patients and 38 eyes of 19 NPDR patients. Thirty-one eyes of 17 normal subjects were enrolled as controls. N1-P1 response amplitude densities (RADs) and P1 implicit times (ITs) from isolated (R1: 0°-2.5°, R2: 2.5°-5°, R3: 5°-10°) and combined (R1 + R2, R2 + R3 and R1 + R2 + R3) annular rings and from four retinal sectors (nasal, N; temporal, T; superior, S and inferior, I) with increasing eccentricities up to 10° (S1, S2, S3, S1 + S2, S1 + S2 + S3) were measured. The statistical differences between DM1 groups and controls were tested by ANOVA. The electrophysiological data were correlated with age, duration of diabetes and glycated hemoglobin (HbA1c) level using the Pearson's test. RESULTS MfERG RADs, but not ITs, from all isolated and combined rings and sectors up to 10° of foveal eccentricity were statistically different between DM1 groups compared to controls. No significant differences were found between NO DR and NPDR patients. The mfERG abnormalities of the central retinal areas were correlated significantly with age in both DM1 groups and with diabetes duration mainly in NPDR group. CONCLUSIONS In DM1 patients, localized retinal dysfunction, described by reduced mfERG RAD, can be observed also in the absence of clinical signs of DR and it is related to aging.
Collapse
Affiliation(s)
- Lucia Ziccardi
- IRCCS-Fondazione Bietti, Via Livenza 1, 00198, Rome, Italy.
| | | | - Fabiana Picconi
- Department of Systems Medicine, University of Rome Tor Vergata, Via Montpellier 1, 00133, Rome, Italy
- Unit of Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita Fatebenefratelli Hospital, Lungotevere de' Cenci 7, 00186, Rome, Italy
| | | | - Marco Lombardo
- Vision Engineering Italy srl, Via Livenza 3, 00198, Rome, Italy
| | - Simona Frontoni
- Department of Systems Medicine, University of Rome Tor Vergata, Via Montpellier 1, 00133, Rome, Italy
- Unit of Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita Fatebenefratelli Hospital, Lungotevere de' Cenci 7, 00186, Rome, Italy
| | | |
Collapse
|
5
|
Loss of CD40 attenuates experimental diabetes-induced retinal inflammation but does not protect mice from electroretinogram defects. Vis Neurosci 2018; 34:E009. [PMID: 28965505 DOI: 10.1017/s0952523817000074] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Chronic low grade inflammation is considered to contribute to the development of experimental diabetic retinopathy (DR). We recently demonstrated that lack of CD40 in mice ameliorates the upregulation of inflammatory molecules in the diabetic retina and prevented capillary degeneration, a hallmark of experimental diabetic retinopathy. Herein, we investigated the contribution of CD40 to diabetes-induced reductions in retinal function via the electroretinogram (ERG) to determine if inflammation plays a role in the development of ERG defects associated with diabetes. We demonstrate that diabetic CD40-/- mice are not protected from reduction to the ERG b-wave despite failing to upregulate inflammatory molecules in the retina. Our data therefore supports the hypothesis that retinal dysfunction found in diabetics occurs independent of the induction of inflammatory processes.
Collapse
|
6
|
Picconi F, Mataluni G, Ziccardi L, Parravano M, Di Renzo A, Ylli D, Pasqualetti P, Studer V, Chioma L, Marfia GA, Frontoni S. Association between Early Neuroretinal Dysfunction and Peripheral Motor Unit Loss in Patients with Type 1 Diabetes Mellitus. J Diabetes Res 2018; 2018:9763507. [PMID: 30402503 PMCID: PMC6193343 DOI: 10.1155/2018/9763507] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 08/30/2018] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVES It has been already confirmed that retinal neurodegeneration has a predictive value in the development of microvascular alterations in diabetic retinopathy. However, no data are available on the association between neuroretinal dysfunction and peripheral motor unit loss. Our study, therefore, was aimed at investigating the hypothesis that retinal neurodegeneration could be considered an early marker of diabetic peripheral neuropathy (DPN). METHODS 20 T1DM patients with no symptoms/signs of peripheral polyneuropathy, without DR or with very mild nonproliferative DR, and 14 healthy controls (C) age- and gender-matched were enrolled. The following electrophysiological tests were performed: standard nerve conduction studies (NCS) and incremental motor unit number estimation (MUNE) from the abductor hallux (AH) and abductor digiti minimi (ADM). Neuroretinal function was studied by multifocal electroretinogram (MfERG) recordings, measuring response amplitude density (RAD) and implicit time (IT) from rings and sectors of superior (S)/inferior (I)/temporal (T)/nasal (N) macular sectors up to 10 degrees of foveal eccentricity. RESULTS MfERG RADs from rings and sectors were significantly reduced in T1DM (p < 0.05) vs. C. ADM MUNE and AH MUNE were significantly decreased in T1DM (p = 0.039 and p < 0.0001, respectively) vs. C. A positive correlation between mean MfERG RADs from the central 5 degrees of the four (S, I, T, and N) macular sectors and lower limb motor unit number (r = 0.50, p = 0.041; r = 0.64, p = 0.005; r = 0.64, p = 0.006; and r = 0.61, p = 0.010, respectively) was observed in T1DM patients. No abnormalities of NCS were found in any subject. CONCLUSIONS The motor unit loss on the one hand and neuroretinal dysfunction on the other hand are already present in T1DM patients without DPN. The relationship between neuroretinal dysfunction and motor unit decline supports the hypothesis that neuroretina may represent a potential "window" to track the early neurogenic damage in diabetes.
Collapse
Affiliation(s)
- Fabiana Picconi
- Unit of Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita Fatebenefratelli Hospital, Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Giorgia Mataluni
- Unit of Disimmune Neuropathies, Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | | | | | | | - Dorina Ylli
- Division of Endocrinology MedStar Washington Hospital Center, MedStar Health Research Institute, Washington, DC, USA
| | - Patrizio Pasqualetti
- Fatebenefratelli Foundation for Health Research and Education, AFaR Division, Rome, Italy
| | - Valeria Studer
- Unit of Disimmune Neuropathies, Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Neuroimmunology and Neuromuscolar Diseases Unit, Foundation IRCCS Neurological Institute Carlo Besta, Milan, Italy
| | - Laura Chioma
- Unit of Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita Fatebenefratelli Hospital, Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Girolama Alessandra Marfia
- Unit of Disimmune Neuropathies, Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| | - Simona Frontoni
- Unit of Endocrinology, Diabetes and Metabolism, S. Giovanni Calibita Fatebenefratelli Hospital, Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
| |
Collapse
|
7
|
Affiliation(s)
- Frank D Verbraak
- Academic Medical Center, Department of Ophthalmology, Department of Biomedical Engineering and Physics, University of Amsterdam, Amsterdam, the Netherlands
| |
Collapse
|
8
|
Reis A, Mateus C, Melo P, Figueira J, Cunha-Vaz J, Castelo-Branco M. Neuroretinal dysfunction with intact blood-retinal barrier and absent vasculopathy in type 1 diabetes. Diabetes 2014; 63:3926-37. [PMID: 24947354 DOI: 10.2337/db13-1673] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
It is unknown whether independent neural damage may occur in the pre-/absent vascular diabetic retinopathy (DR). To exclude vasculopathy, it is important to measure the integrity of the blood-retinal barrier (BRB). This cross-sectional study addressed this problem in type 1 diabetic patients with normal ocular fundus and absent breakdown of the BRB (confirmed with vitreous fluorometry). These were compared with a group with disrupted BRB (with normal fundus or initial DR) and normal controls. Multifocal electroretinography and chromatic/achromatic contrast sensitivity were measured in these 42 patients with preserved visual acuity. Amplitudes of neurophysiological responses (multifocal electroretinogram) were decreased in all eccentricity rings in both clinical groups, when compared with controls, with sensitivity >78% for a specificity level of 90%. Implicit time changes were also found in the absence of initial DR. Impaired contrast sensitivity along chromatic axes was also observed, and achromatic thresholds were also different between controls and both clinical groups. The pattern of changes in the group without baseline BRB permeability alterations, as probed by psychophysical and electrophysiological measurements, does thereby confirm independent damage mechanisms. We conclude that retinal neuronal changes can be diagnosed in type 1 diabetes, independently of the breakdown of the BRB and onset of vasculopathy.
Collapse
Affiliation(s)
- Aldina Reis
- Visual Neuroscience Laboratory, Institute for Biomedical Imaging in Life Sciences, Faculty of Medicine, University of Coimbra, Coimbra, Portugal Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal Coimbra University Hospital, Coimbra, Portugal
| | - Catarina Mateus
- Visual Neuroscience Laboratory, Institute for Biomedical Imaging in Life Sciences, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Pedro Melo
- Visual Neuroscience Laboratory, Institute for Biomedical Imaging in Life Sciences, Faculty of Medicine, University of Coimbra, Coimbra, Portugal Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal
| | - João Figueira
- Visual Neuroscience Laboratory, Institute for Biomedical Imaging in Life Sciences, Faculty of Medicine, University of Coimbra, Coimbra, Portugal Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal Coimbra University Hospital, Coimbra, Portugal
| | - José Cunha-Vaz
- Visual Neuroscience Laboratory, Institute for Biomedical Imaging in Life Sciences, Faculty of Medicine, University of Coimbra, Coimbra, Portugal Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal Coimbra University Hospital, Coimbra, Portugal
| | - Miguel Castelo-Branco
- Visual Neuroscience Laboratory, Institute for Biomedical Imaging in Life Sciences, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| |
Collapse
|
9
|
Multifocal electroretinogram responses in Nepalese diabetic patients without retinopathy. Doc Ophthalmol 2014; 129:39-46. [DOI: 10.1007/s10633-014-9447-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 05/27/2014] [Indexed: 10/25/2022]
|
10
|
Abstract
In this review article, we first present a brief overview of the vascular and neural components of diabetic retinopathy. Next, the multifocal electroretinogram (mfERG) technique, which can map neuroretinal function noninvasively, is described. Findings in diabetic retinal disease using the mfERG are reviewed. We then describe the progress that has been made to predict the onset and progression of diabetic retinopathy and edema in specific retinal locations, using quantitative models based on the mfERG. Finally, we consider the implications for the future of these predictive models.
Collapse
Affiliation(s)
- Marcus A Bearse
- School of Optometry, University of California, Berkeley, 360 Minor Hall, Berkeley, CA, 94720-2020, USA,
| | | |
Collapse
|