BACKGROUND: Retinopathy of prematurity (ROP) is a vision-threatening disease in premature infants. Serum adiponectin (APN) concentrations positively correlate with postnatal growth and gestational age, important risk factors for ROP development. Dietary ω-3 (n-3) long-chain polyunsaturated fatty acids (ω-3 LCPUFAs) suppress ROP and oxygen-induced retinopathy (OIR) in a mouse model of human ROP, but the mechanism is not fully understood. OBJECTIVE: We examined the role of APN in ROP development and whether circulating APN concentrations are increased by dietary ω-3 LCPUFAs to mediate the protective effect in ROP. DESIGN: Serum APN concentrations were correlated with ROP development and serum ω-3 LCPUFA concentrations in preterm infants. Mouse OIR was then used to determine whether ω-3 LCPUFA supplementation increases serum APN concentrations, which then suppress retinopathy. RESULTS: We found that in preterm infants, low serum APN concentrations positively correlate with ROP, and serum APN concentrations positively correlate with serum ω-3 LCPUFA concentrations. In mouse OIR, serum total APN and bioactive high-molecular-weight APN concentrations are increased by ω-3 LCPUFA feed. White adipose tissue, where APN is produced and assembled in the endoplasmic reticulum, is the major source of serum APN. In mouse OIR, adipose endoplasmic reticulum stress is increased, and APN production is suppressed. ω-3 LCPUFA feed in mice increases APN production by reducing adipose endoplasmic reticulum stress markers. Dietary ω-3 LCPUFA suppression of neovascularization is reduced from 70% to 10% with APN deficiency. APN receptors localize in the retina, particularly to pathologic neovessels. CONCLUSION: Our findings suggest that increasing APN by ω-3 LCPUFA supplementation in total parental nutrition for preterm infants may suppress ROP.
BACKGROUND: Since they were first derived more than three decades ago, embryonic stem cells have been proposed as a source of replacement cells in regenerative medicine, but their plasticity and unlimited capacity for self-renewal raises concerns about their safety, including tumour formation ability, potential immune rejection, and the risk of differentiating into unwanted cell types. We report the medium-term to long-term safety of cells derived from human embryonic stem cells (hESC) transplanted into patients. METHODS: In the USA, two prospective phase 1/2 studies were done to assess the primary endpoints safety and tolerability of subretinal transplantation of hESC-derived retinal pigment epithelium in nine patients with Stargardt's macular dystrophy (age >18 years) and nine with atrophic age-related macular degeneration (age >55 years). Three dose cohorts (50,000, 100,000, and 150,000 cells) were treated for each eye disorder. Transplanted patients were followed up for a median of 22 months by use of serial systemic, ophthalmic, and imaging examinations. The studies are registered with ClinicalTrials.gov, numbers NCT01345006 (Stargardt's macular dystrophy) and NCT01344993 (age-related macular degeneration). FINDINGS: There was no evidence of adverse proliferation, rejection, or serious ocular or systemic safety issues related to the transplanted tissue. Adverse events were associated with vitreoretinal surgery and immunosuppression. 13 (72%) of 18 patients had patches of increasing subretinal pigmentation consistent with transplanted retinal pigment epithelium. Best-corrected visual acuity, monitored as part of the safety protocol, improved in ten eyes, improved or remained the same in seven eyes, and decreased by more than ten letters in one eye, whereas the untreated fellow eyes did not show similar improvements in visual acuity. Vision-related quality-of-life measures increased for general and peripheral vision, and near and distance activities, improving by 16-25 points 3-12 months after transplantation in patients with atrophic age-related macular degeneration and 8-20 points in patients with Stargardt's macular dystrophy. INTERPRETATION: The results of this study provide the first evidence of the medium-term to long-term safety, graft survival, and possible biological activity of pluripotent stem cell progeny in individuals with any disease. Our results suggest that hESC-derived cells could provide a potentially safe new source of cells for the treatment of various unmet medical disorders requiring tissue repair or replacement. FUNDING: Advanced Cell Technology.
Age is a major risk factor in age-related macular degeneration (AMD), but the underlying cause is unknown. We find increased Rho-associated kinase (ROCK) signaling and M2 characteristics in eyes of aged mice, revealing immune changes in aging. ROCK isoforms determine macrophage polarization into M1 and M2 subtypes. M2-like macrophages accumulated in AMD, but not in normal eyes, suggesting that these macrophages may be linked to macular degeneration. M2 macrophages injected into the mouse eye exacerbated choroidal neovascular lesions, while M1 macrophages ameliorated them, supporting a causal role for macrophage subtypes in AMD. Selective ROCK2 inhibition with a small molecule decreased M2-like macrophages and choroidal neovascularization. ROCK2 inhibition upregulated M1 markers without affecting macrophage recruitment, underlining the plasticity of these macrophages. These results reveal age-induced innate immune imbalance as underlying AMD pathogenesis. Targeting macrophage plasticity opens up new possibilities for more effective AMD treatment.
PURPOSE: To determine whether there is an association between response to intravitreal anti-vascular endothelial growth factor agents and genotype in patients with neovascular age-related macular degeneration. METHODS: Analysis of the current literature evaluating pharmacogenetics of treatment response in patients with neovascular age-related macular degeneration. RESULTS: Studies have demonstrated associations between various genotypes and response to intravitreal anti-vascular endothelial growth factor agents. Lower-risk genotypes of the CFH, ARMS2, HTRA1, and VEGF-A genes may be associated with improved visual outcomes. Additionally, frequency of injections may be associated with certain genotypes. CONCLUSION: Genetic background may influence an individual's response to treatment of neovascular age-related macular degeneration. Further studies to investigate biologic pathways of neovascular age-related macular degeneration and gene products that are directly involved might lead to better understanding of contribution of various genes to treatment response.
PURPOSE: To study the association between periodontal disease (PD) and age-related macular degeneration (AMD). METHODS: For this cross-sectional analysis, 8,208 adults aged 40 years or older with retinal photographs graded for AMD were used from the National Health and Nutrition Examination Survey III. National Health and Nutrition Examination Survey III standardized dental measurements of PD status (defined as loss of >3 mm of attachment between the gum and tooth in at least 10% of sites measured). Participants were stratified into 60 years or younger and older than 60 years of age groups. Association between PD and AMD was assessed while controlling for sex, race, education, poverty income ratio, smoking, hypertension, body mass index, cardiovascular disease, and C-reactive protein. RESULTS: In this population, a total of 52.30% had PD, and the prevalence of AMD was 11.45%. Logistic regression model controlled for confounders and stratified by age 60 years or younger versus older than 60 years showed PD to be independently associated with an increased risk for AMD (odds ratio = 1.96, 95% confidence interval = 1.22-3.14, P = 0.006) for those aged 60 years or younger but not for subjects older than 60 years (odds ratio = 1.32, confidence interval = 0.93-1.90, P = 0.120). CONCLUSION: In this population-based study, PD is independently associated with AMD in those aged 60 years or younger.
We present a novel fully automated algorithm for the detection of retinal diseases via optical coherence tomography (OCT) imaging. Our algorithm utilizes multiscale histograms of oriented gradient descriptors as feature vectors of a support vector machine based classifier. The spectral domain OCT data sets used for cross-validation consisted of volumetric scans acquired from 45 subjects: 15 normal subjects, 15 patients with dry age-related macular degeneration (AMD), and 15 patients with diabetic macular edema (DME). Our classifier correctly identified 100% of cases with AMD, 100% cases with DME, and 86.67% cases of normal subjects. This algorithm is a potentially impactful tool for the remote diagnosis of ophthalmic diseases.
Purpose: Patients with macular disease often report experiencing metamorphopsia (visual distortion). Although typically measured with Amsler charts, more objective and quantitative assessments of perceived distortion are desirable to effectively monitor the presence, progression and remediation of visual impairment. Methods: Participants with binocular (n = 33) and monocular (n= 50) maculopathy across seven disease groups, and control participants (n = 10) with no identifiable retinal disease completed a modified Amsler Grid assessment (presented on a computer screen with eye tracking to ensure fixation compliance) and two novel objective measures of metamorphopsia in the central five degrees of visual field. 81% (67/83) of participants completed a task requiring them to configure eight dots in the shape of a square, and 64% (32/50) of participants experiencing monocular distortion completed a spatial alignment task using dichoptic stimuli. 10 controls completed all tasks. Results: Horizontal and vertical distortion magnitudes were calculated for each of the three assessments. Distortion magnitudes were significantly higher in patients than controls in all assessments. There was no significant difference in magnitude of distortion across different macular diseases. Among patients, there were no significant correlations between overall magnitude of distortion among any of the three measures and no significant correlations in localized measures of distortion. Conclusions: Three alternative quantifications of monocular spatial distortion in the central visual field generated uncorrelated estimates of visual distortion. It is therefore unlikely that metamorphopsia is caused solely by displacement of photoreceptors in the retina, but instead involves additional top-down information, knowledge about the scene, and perhaps, cortical reorganization.
Neuropilin-1 (NRP1) is a receptor for vascular endothelial growth factor (VEGF). A soluble isoform of Nrp1 (sNrp1) has not been described in the mouse. Our goal was to examine the expression of mouse sNrp1 during liver development and regeneration.sNrp1 was cloned from mouse liver. The expression of sNrp1 and VEGF was examined in mouse liver during post-natal development and regeneration using northern blot, western blot, in situ hybridisation, and immunohistochemical analyses. HGF/NRP1 binding was examined in vitro.A novel 588-amino acid sNrp1 isoform was found to contain the ligand binding regions of Nrp1. The adult liver expressed more sNrp1 than full-length Nrp1. In vivo, hepatocytes constitutively expressed VEGF and sNrp1 in the quiescent state. sNrp1 was highly up-regulated at P20, a time point coinciding with a plateau in liver and body weights. Following hepatectomy, endogenous levels of sNrp1 decreased during the rapid growth phase, and VEGF levels were highest just prior to and during the angiogenic phase. sNrp1 levels again rose 5-10 days post-hepatectomy, presumably to control regeneration. HGF protein bound NRP1 and binding was competed with sNRP1.We cloned a novel mouse sNrp1 isoform from liver and provide evidence that this endogenous angiogenesis inhibitor may regulate VEGF or HGF bioavailability during normal physiological growth and development as well as during liver regeneration.