Study of the Discriminating Power of a Blood Biomarker for Omega-3 Polyunsaturated Fatty Acid Content of the Retina for Age-related Macular Degeneration (AMD)

Age-related macular degeneration is a chronic degenerative retinal disease, which can lead to a progressive loss of visual acuity without affecting peripheral vision. It is a public health problem as it remains the leading cause of visual impairment in people over 50 years of age in industrialized countries.

Age-related macular degeneration has two clinical forms:

• Atrophic or dry form: progressive disappearance of photoreceptors, alteration of the pigmentary epithelium leading to a thinning of the macula.
• Exudative or humid form: development of immature choroidal neo-vessels, leading to the formation of edema or intra or sub-retinal hemorrhage at the origin of the symptoms.

There are still many questions about the pathogenesis of age-related macular degeneration, and there is currently no etiological treatment. The disorder is thought to have a multifactorial, genetic and environmental origin.

Among the environmental risk factors, dietary intake of omega-3 polyunsaturated acids and its effect on the retina are factors that influence both the incidence and progression of the disease. However, intervention studies have not been able to demonstrate the preventive value of omega-3 polyunsaturated fatty acids. It is likely that the precise identification of patients who could benefit from this supplementation is necessary. Currently, the estimation of dietary intake of omega-3 polyunsaturated fatty acids is based on dietary surveys, which implies a number of limits. A blood biomarker of omega-3 polyunsaturated fatty acid content in the retina has been previously identified, which if lowered may be a risk factor for age-related macular degeneration. A low level could also help to identify patients who would best respond to supplementation. A publication has been submitted and a patent has been filed for this biomarker. The objective of this project is to confirm the relationship between this biomarker and the presence of age-related macular degeneration. The analysis will be refined by correlating the discriminating character of the biomarker with factors that may influence the intestinal metabolism of dietary lipids and their bioavailability in the blood. For this purpose, the status of the subjects with regard to their intestinal flora (microbiota) will be evaluated. The relationship between lipid metabolism, microbiota and age-related macular degeneration should also provide a better understanding of the pathophysiological mechanisms that link diet, lipid metabolism and age-related macular degeneration.