1
|
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
|
2
|
Li Y, Lapina N, Weinzierl N, Bonde L, Boedtkjer E, Schubert R, Moshage H, Wohlfart P, Schilling L. A novel method to isolate retinal and brain microvessels from individual rats: Microscopic and molecular biological characterization and application in hyperglycemic animals. Vascul Pharmacol 2018; 110:24-30. [PMID: 30003960 DOI: 10.1016/j.vph.2018.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 06/29/2018] [Accepted: 07/07/2018] [Indexed: 11/17/2022]
Abstract
Alterations in the retinal microvessel (RMV) compartment occurring in systemic disease states such as diabetes may eventually contribute to blindness. To specifically address the pathophysiological role of the microvasculature we developed a new method for RMV bulk isolation from individual rats. The extraction procedure performed in the cold throughout takes less than one hour. Slight modifications enable isolation of brain microvessels (BMVs) for comparison. Microscopically, RMVs and BMVs consisted mainly of capillaries of good structural integrity. The endothelial cell/pericyte ratio was approximately 1.8 in RMVs and 2.7 in BMVs, well in agreement with data from intact vascular beds. Total RNA extracted from individual rats amounted to approximately 7 ng in RMVs, 50 ng in BMVs, and 155 ng in pial arteries (which were also isolated) with highly preserved integrity throughout. Measurements using microfluidic card methodology revealed segregation of RMVs, BMVs, and pial arteries in distinct clusters based on principal component analysis. In all three vascular compartments endothelial cell-specific markers were significantly enriched. Similarly, pericyte-specific markers displayed accumulation in RMVs, BMVs, and pial arteries, the latter probably reflecting the common ontogenetic origin of pericytes and smooth muscle cells. Isolation of RMVs, BMVs, and pial arteries from rats suffering from 8-weeks hyperglycemia yielded expression patterns of endothelial cell- and pericyte-specific marker genes largely comparable to those obtained in control rats. Our newly developed protocols allow for selective studies of RMVs from individual rats to characterize reactive pathways, in comparison with the ontogenetically closely related BMVs. Moreover, our protocols with inclusion of pial arteries enable comparative studies of the macro- and microvasculature from the same organ.
Collapse
Affiliation(s)
- Youhai Li
- Division of Neurosurgical Research, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Natalia Lapina
- Division of Neurosurgical Research, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Nina Weinzierl
- Division of Neurosurgical Research, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Lisbeth Bonde
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Ebbe Boedtkjer
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Rudolf Schubert
- Cardiovascular Physiology, Center for Biomedicine and Medical Technology (CBTM), Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany; European Center of Angioscience (ECAS), Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Han Moshage
- Department of Gastroenterology and Hepatology, Department of Laboratory Medicine, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Paulus Wohlfart
- Sanofi Aventis Deutschland GmbH, TA, Diabetes R&D, Industriepark Hoechst, Frankfurt, Germany
| | - Lothar Schilling
- Division of Neurosurgical Research, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany; European Center of Angioscience (ECAS), Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
| |
Collapse
|
3
|
Ferrini MG, Rivera S, Moon J, Vernet D, Rajfer J, Gonzalez-Cadavid NF. The Genetic Inactivation of Inducible Nitric Oxide Synthase (iNOS) Intensifies Fibrosis and Oxidative Stress in the Penile Corpora Cavernosa in Type 1 Diabetes. J Sex Med 2010; 7:3033-44. [DOI: 10.1111/j.1743-6109.2010.01884.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
4
|
Tortoriello DV, McMinn JE, Chua SC. Increased expression of hypothalamic leptin receptor and adiponectin accompany resistance to dietary-induced obesity and infertility in female C57BL/6J mice. Int J Obes (Lond) 2006; 31:395-402. [PMID: 16865100 DOI: 10.1038/sj.ijo.0803392] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Obesity is strongly associated with female infertility, but the mechanisms underlying this relationship are largely unknown. METHODS We investigated the effect of increasing dietary fat percentage upon body mass, hypothalamic neuropeptide gene expression, adipose hormone secretion and fertility in females of the inbred mouse strains C57BL/6J and DBA/2J. To assess the effect of obesity independent of dietary influence, we also compared these parameters in wild-type female C57BL/6J mice to those congenic for the obesogenic mutations ob/ob and A(y)/a. RESULTS After 24 weeks, rather than exhibiting an obese, leptin-resistant phenotype like their female DBA/2J counterparts, wild-type female C57BL/6J mice remained lean, fertile and manifested increased hypothalamic LEPR-B expression. Although both mutant genotypes were associated with obesity and subfertility, ob/ob mice demonstrated significantly increased hypothalamic LEPR-B expression, whereas A(y)/a mice had a significant reduction. Interestingly, wild-type female C57BL/6J mice were noted to manifest significantly higher and lower levels of adiponectin and tissue plasminogen activator inhibitor-1 (tPAI-1), respectively, than weight-matched wild-type female DBA/2J mice. CONCLUSIONS We conclude that (1) resistance to the obese-infertile phenotype in female C57BL/6J mice is associated with increased hypothalamic leptin receptor expression and alterations in adipokine levels consistent with decreased adipose tissue inflammation and (2) that long-standing hyperleptinemic obesity in mice is associated with a downregulation of the hypothalamic leptin receptor.
Collapse
Affiliation(s)
- D V Tortoriello
- Division of Reproductive Endocrinology, Department of Obstetrics and Gynecology, Columbia University, New York, NY 10032, USA.
| | | | | |
Collapse
|
5
|
Abstract
A prominent and early feature of the retinopathy of diabetes mellitus is a diffuse increase in vascular permeability. As the disease develops, the development of frank macular oedema may result in vision loss. That reactive oxygen species production is likely to be elevated in the retina, and that certain regions of the retina are enriched in substrates for lipid peroxidation, may create an environment susceptible to oxidative damage. This may be more so in the diabetic retina, where hyperglycaemia may lead to elevated oxidant production by a number of mechanisms, including the production of oxidants by vascular endothelium and leukocytes. There is substantial evidence from animal and clinical studies for both impaired antioxidant defences and increased oxidative damage in the retinae of diabetic subjects that have been, in the case of animal studies, reversible with antioxidant supplementation. Whether oxidative damage has a causative role in the pathology of diabetic retinopathy, and thus whether antioxidants can prevent or correct any retinal damage, has not been established, nor has the specific nature of any damaging species been characterised.
Collapse
Affiliation(s)
- David M van Reyk
- Department of Health Sciences, University of Technology, Sydney, New South Wales, Australia.
| | | | | |
Collapse
|
6
|
Wang S, Wu Z, Sorenson CM, Lawler J, Sheibani N. Thrombospondin-1-deficient mice exhibit increased vascular density during retinal vascular development and are less sensitive to hyperoxia-mediated vessel obliteration. Dev Dyn 2003; 228:630-42. [PMID: 14648840 DOI: 10.1002/dvdy.10412] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Thrombospondin-1 (TSP1) is a natural inhibitor of angiogenesis. Its expression is most prominent during the late stages of vascular development and in the adult vasculature. Our previous studies have shown that TSP1 expression promotes a quiescent, differentiated phenotype of vascular endothelial cells. However, the physiological role TSP1 plays during vascular development and neovascularization requires further delineation. Here, we investigated the role of TSP1 during development of retinal vasculature and retinal neovascularization during oxygen-induced ischemic retinopathy. The retinal vascular density was increased in TSP1-deficient (TSP1-/-) mice compared with wild-type mice. This finding was mainly attributed to increased number of retinal endothelial cells in TSP1-/- mice. During oxygen-induced ischemic retinopathy, the developing retinal vasculature of TSP1-/- mice was less sensitive to vessel obliteration induced by hyperoxia but exhibited a similar level of neovascularization induced by normoxia compared with wild-type mice. This finding is consistent with the similar pattern of VEGF expression detected in wild-type and TSP1-/- mice. Furthermore, the increased expression of TSP1 during development of retinal vasculature was not affected by oxygen-induced ischemic retinopathy. In addition, the regression of ocular embryonic (hyaloid) vessels, as well as the newly formed retinal vessels during oxygen-induced ischemic retinopathy, was delayed in TSP1-/- mice. Therefore, TSP1 is a modulator of vascular homeostasis and its expression is essential for appropriate remodeling and maturation of retinal vasculature.
Collapse
Affiliation(s)
- Shoujian Wang
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, Wisconsin 53792, USA
| | | | | | | | | |
Collapse
|