Eine lokale Aktivierung des Komplementsystems im RPE ist ein pathogener Faktor der AMD. Neben der Wirkung von angiogenen Faktoren wie VEGF könnte eine Aktivierung des Blutgerinnungssystems im RPE dazu beitragen, dass sich aus einer trockenen eine feuchte AMD entwickelt. Dies könnte auf mehreren Ebenen geschehen: Gerinnungsfaktoren könnten die Expression der Komplementfaktoren und der angiogenen Faktoren regulieren sowie Wirkungen auf die Proliferation und Migration der RPE-Zellen besitzen. Eine Stimulierung der Proliferation und Migration der RPE-Zellen trägt zur Ausbildung von CNV-Membranen bei. Es ist aber bis jetzt nichts darüber bekannt, ob RPE-Zellen Faktoren des Blutgerinnungssystems exprimieren und ob z.B. Thrombin (als zentrale Protease des Blutgerinnungssystems) die Genexpression von Komplementfaktoren und von VEGF im RPE beeinflusst. Die Ziele der vorliegenden Dissertation waren daher: ● Nachweis der mRNA-Expression von Blutgerinnungs- und Komplementfaktoren im RPE; ● Nachweis der Wirkung von Thrombin auf die Expression von VEGF und von Komplementfaktoren, sowie auf die Proliferation und Migration der RPE-Zellen; und ● Nachweis der Wirkung der Komplementfaktoren C5a und C9 auf die Sekretion von VEGF und die Proliferation und Migration der RPE-Zellen.

This dissertation considers the interactions of users who have been diagnosed with Age-related Macular Degeneration (AMD), the leading cause of blindness in adults 65 years and older. The investigation focused on the quantification of behaviors and strategies used by this growing subset of computer users. Participants diagnosed with AMD and age-matched controls without any ocular disease completed a series of visual search, icon selection and manipulation tasks with desktop or handheld PCs. Participants searched, selected and manipulated familiar playing card icons under varied icon set sizes, inter-icon spacing, icon sizes and auditory feedback. A comprehensive account of the interaction was made using a collection of efficiency, accuracy and information processing metrics. While all participants demonstrated a high rate for successful task completion, analyses revealed participants' overall task efficacy to be coupled with features of the interface and also strongly linked with measures of ocular health and personal factors. The outcomes of this study contribute to a growing body of work which informs a framework of performance thresholds for critical graphical user interface interactions based on visual profile, interface features and supplemental non-visual cues, including the following: The impact of auditory feedback on task interaction and information processing for visually impaired versus visually healthy older adults; The observed of use of the mouse pointer or stylus as means to direct attention during visual search and the implications of manual dexterity on visual search; The presence of speed accuracy trade-offs in handheld PC interaction performance for individuals based on their contrast sensitivity and near visual acuity; The shifting impact of increased icon spacing on visual search and movement times, versus its role in the accuracy of icon release; The utility for non-clinically acquired summaries of visual health to effectively predict performance decrements in handheld or desktop interaction; Emergent differences between handheld and desktop interaction and the most influential visual factors informing performance on each; and Empirical evidence that older adults, even with visual impairments can interact with small handheld displays, in spite of the size images.

Age-related macular degeneration (AMD) is the leading cause for visual impairment and blindness in the elder population of developed countries. The primary underlying cause for significant visual loss is the choroidal neovascularization (CNV). Current treatment strategies for AMD include laser photocoagulation, photodynamic therapy (PDT) and excision of neovascular membranes, but have met with limited success. In our previous studies, we demonstrated that gene delivery of angiogenesis inhibitor vasostatin (VS) attenuated the corneal neovascularization in animals. The primary objective of this study was to investigate gene delivery of vasostatin (VS) attenuated the choroidal neovascularization in animals. Retinal and visual function will be evaluated. However, systematic expression of angiogenesis inhibitor may bring adverse effects to physiological processes. The feasibility, efficiency and safety of gene delivery with systemic and local routes were evaluated. Intramuscular polymer-based gene delivery had no side effect such as virus vector and revealed the safety. Recombinant adenovirus (Ad) was used gene delivery system because of its high titer, wide host range, and transduction efficiency. Adeno-associated virus (AAV) represents highly efficient that can facilirate long-term transduction. We propose to improve the efficacy and safety of VS gene delivery, and to search for the effective delivery route and other adjuvant therapy in conjunction with VS for treatment of CNV. Recently, PDT with veteporfin is an established treatment for subfoveal CNV secondary to AMD. We tried to compare the effect and safety of standard and reduced-dose light application PDT in an animal mocel of CNV. The 180-residue VS and its 48-residue (VS48) inhibited the migration and tube formation in cultured endothelial cells. Topical VS application suppresses the progression of laser-induced CNV via angiogenesis ihhibition, as well as in VS48. VS-48 inhibited the growthof vessels in arota rings. Electroretinograms (ERG) analysis revealed that topical VS-48 application for 21 days had no effect on rat retinal functions. Topical VS-48 treatment significantly reversed the CNV-induced alterations in ERG. Transfection of pCMV3-VS into muscle cells resulted in increased production and release of exogenous VS, which specifically inhibited the proliferation of endothelial cells. Rats treated with intrmuscular injection with PVP-VS also showed a significant reduction in the CNV lesions for at least 42 days. Subconjunctival injection with Ad vector revealed no retinal toxicity in ERG. Ad-luciferase via subconjunctival injections showed ocular expression for as long as 112 days by using bioluminescence image analysis in rodent. AAV-luciferase via subconjunctival injections showed ocular expression for as long as 365 days by using bioluminescence image analysis in mice, and AAV serotype 5-luciferase even showed expression lasting for 2 years. Suppression of laser photocoagulation¡Vinduced CNV by Ad-VS was documented in rat model. Combination therapies are important as treatment options. We demonstrated that PDT could effectively attenuate CNV in a rat model, and reduced doses, worked just as well as the standard dose. In the preliminary study of PDT combined topical VS application, treatment led to CNV attenuation more than alone with PDT. The above experiments would enable us to demonstrate that the vasostatin delivery might be a promising strategy for the treatment of AMD and other retinal or ocular disorders. Furthermore, the results from animal studies might be extrapolated for future clinical application.

Mutations in BEST1, the gene encoding for Bestrophin-1 (Best1), cause five, clinically distinct inherited retinopathies: Best vitelliform macular dystrophy (BVMD), adult-onset vitelliform macular dystrophy (AVMD), autosomal recessive bestrophinopathy (ARB), autosomal dominant vitreoretinochoroidopathy (ADVIRC), and retinitis pigmentosa (RP). Little is known regarding how BEST1 mutations cause disease and why mutations cause multiple disease phenotypes. Within the eye, Best1 is a homo-oligomeric, integral membrane protein that is exclusively localized to the basolateral plasma membrane of the retinal pigment epithelium (RPE). Here, it regulates intracellular Ca2+ signaling and putatively mediates anion transport. Since defects in localization and oligomerization are known to underlie other channelopathies, we investigated how mutations causal for BVMD, AVMD, ARB, ADVIRC, and RP impact the localization and oligomerization of Best1. We generated replication-defective adenoviral vectors encoding for WT and 31 mutant forms of Best1 associated with these five diseases and expressed them in confluent, polarized Madin-Darby canine kidney and/or RPE cells. Localization was assessed via immunofluorescence and confocal microscopy. Oligomerization was examined using live-cell fluorescence resonance energy transfer (FRET) as well as reciprocal co-immunoprecipitation experiments. We report that all 31 BVMD, AVMD, ARB, ADVIRC, and RP mutants tested can reciprocally co-immunoprecipitate with and exhibit comparable FRET efficiencies to WT Best1, indicative of unimpaired oligomerization. While all RP and ADVIRC mutants were properly localized to the basolateral plasma membrane, many but not all AVMD, ARB, and BVMD mutants were mislocalized to intracellular compartments. When co-expressed with WT Best1, mislocalized mutants predominantly co-localized with WT Best1 in intracellular compartments. Studies involving four ARB truncation mutants reveal that the first 174 amino acids are sufficient to mediate oligomerization with WT Best1 and that amino acids 472-585 are not necessary for proper trafficking. We conclude that, although mislocalization is a common result of BEST1 mutation, it is not an absolute feature of any individual bestrophinopathy. Moreover, we show that some recessive mutants mislocalize WT Best1 when co-expressed, indicating that mislocalization cannot, on its own, generate a disease phenotype, and that the absence of Best1 at the plasma membrane is well tolerated.

No description available.

Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly worldwide. Due to the inadequacy of current pharmacotherapies, novel molecular targets must be sought as potential therapeutic candidates. Furthermore, there is a need for more efficient and cost-effective animal models of this pathology in order to accelerate in vivo investigations. / Our laboratory is in possession of human choroidal neovascular membranes which we examined for expression of cyclooxygenase (COX)-2. This expression was characterized in retinal pigment epithelial, vascular endothelial, and fibroblast cells and correlated with patient age. We also looked at the feasibility of creating a rabbit laser-injury model to adequately mimic human neovascular AMD. / Our results suggest that anti-COX-2 therapies may be beneficial to some patients with neovascular AMD. Moreover, there is strong potential for the development of clinically relevant choroidal neovascularization in rabbits using the laser-injury technique. This approach may yield a novel, cost-effective AMD model.

Age-related macular degeneration (AMD) is a principal cause of blindness in the United States and other industrialized nations. An estimated 10 million Americans are afflicted with AMD, which is comparable in scope to the 12 million living with cancer, or the 5 million with Alzheimer’s disease. The prevalence of AMD steadily increases with age, affecting 2% of the population at age 40, and one in four people by age 80. For reasons that are not fully understood, AMD is more common in lightly-pigmented and female populations. Treatment of AMD is largely an unmet need: There are no FDA approved therapies except for a small percentage of individuals with end-stage disease. This dissertation investigates the mechanisms of AMD pathogenesis and offers insight into novel therapeutic strategies for this disease.

ABSTRACT IMPORTANCE: Age-related macular degeneration (AMD) is a leading cause of low vision in elderly population. The association of vascular and renal conditions has been reported inconsistently. Unfolding the association may provide the insight to eye care providers to take account general health management into eye care. OBJECTIVES: To investigate the prevalence of the vascular and renal comorbidities with AMD, examine the association of a single or combination of these comorbidities with AMD. DSIGN AND PARTICIPANTS: Population-base cross-sectional study involved the adults aged 40 years or older (N=4596) who participated in the 2005 to 2008 National Health and Nutrition Examination Survey (NHANES), a national representative population-based survey of non-institutionalized US residents. MAIN OUTCOMES AND MEASURES: AMD was defined by the presence of drusen and presence of pigmental abnormality. Angina pectoris (AP), coronary heart disease (CHD), congestive heart failure (CHF) and myocardial infarction (MI), and stroke, assessed by self-report by the questionnaire of medical conditions, Chronic kidney disease (CKD), assessed by self-report and estimation of glomerular filtration rate (GFR) and the level of urine albumin. Heart disease (HD) was defined as having AP or CHF or CHD or MI. RESULTS: Among individuals with AMD, 6% had AP, 10% had CHD, 7% had CHF, 10% had MI, 13% had stroke, and 29% had CKD. The weighted prevalence of these conditions were significantly higher than those without AMD (All P-values CONCLUSION AND RELEVANCE: These findings from the nationally-representative sample of the US population highlight the prevalence of vascular and renal comorbidities associated with AMD, the modest evidence of relationship of each single comorbidity, and strong association of combination of stroke and CKD to AMD independent of age, gender, and other factors. Because of the cross-sectional design, the results of this study can not address a causal relationship between AMD and the examined comorbidities. It is unclear whether AMD and comorbidities arise from individual predisposition to vascular and renal diseases or whether complications from these morbidities increase the risk of AMD. However, the important caveat is that preventive and care management for the examined comorbidities may lessen the severity of symptoms or prevent AMD.

Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / CD-ROM i ficka. Härtill 5 uppsatser.

Age-related macular degeneration (AMD) is a prevalent cause of vision loss and irreversible blindness that affects more than 11 million Americans. AMD is a multifactorial disease with a number of genetic, demographic, and environmental risk factors. Currently the etiology of AMD is still unclear and there are no effective cure for this devastating disease, but recent studies have demonstrated that RORA is a candidate gene involved in AMD pathophysiology. RORA is a critical regulator of multiple biological processes and has been implicated in various physiological processes including circadian rhythm, lipid metabolism, photoreceptor development, autism, and inflammation. Our current study will explore in depth the role of RORA in AMD. We will look at the effects of RORA in the retina of mice. Localization studies of retinal tissues obtained from mice with a conditional knockout of RORA in epithelial cells showed little effect of RORA on structural cells of the retina. However, there was a decrease in VEGF and TGF-B proteins in RORA knockout. This is an interesting finding because VEGF and TGF-B has an important function in angiogenesis and neovascularization which are pathophysiological effects of AMD. In addition, we will try to identify gene targets of RORA that have also been linked with AMD. By identifying the targets of RORA and discovering how RORA regulates these targets, we hope to better understand the role of RORA in AMD pathophysiology. ChIP-seq and software analysis of the data was performed to identify all genomic targets of RORA linked with AMD. A number of promising genes were found in both RORA and AMD networks. The next step of this study is to perform quantitative analysis of these genes and how their expression is affected by RORA. Also, we will perform additional conditional RORA knockout models in cone cells and developing retinal cells to further understand the role of RORA in the retina and AMD pathogenesis.