AMD and micronutrients
AMD and micronutrients oxidant scavenging enzymes can normally neutralize the free radicals that are formed. If these protective mechanisms are impaired in their function or the amount of radicals formed exceeds the capacity of the antioxidative mechanisms, a dangerous state of crisis can develop, since damage to the respiratory chain complexes by free radicals further increases radical formation. In the case of AMD, there is an increased formation of free radicals primarily because a component of lipofuscin, the so-called A2E (N-retinylidene-N-retinylethanolamine) has an inhibitory effect on complex IV of the mitochondrial respiratory chain. A2E interrupts the flow of electrons via cytochrome C to complex IV. As a result, more electrons are transferred to oxygen at complex III and more superoxide radicals are formed, which damage proteins and membrane structures (Fig. 3). (2) In addition, coenzyme Q10 is a fat-soluble antioxidant that integrates into cellular and mitochondrial membrane structures and protects them from radical-induced damage. Coenzyme Q10 can regenerate other antioxidants such as vitamin C and vitamin E, which can also scavenge more free radicals. As a result, coenzyme Q10 can protect the body's own structures from oxidative damage both directly and indirectly. Due to the increased oxidative stress, the retina has a relatively high concentration of coenzyme Q10. However, the levels decrease significantly with age (Fig. 4). Due to the decreasing coenzyme Q10 content, H + Superoxide radicals . H + O - 2 . O - 2 Complex Q10 e Q10 Complex I e e e III Complex II NADH NAD+ Succinate Fumarate H + . O - H + 2 Complex IV N A2E OH Fig. 3: A component of lipofuscin, A2E inhibits the transfer of electrons in the mitochondrial respiratory chain. As a result, more electrons are transferred to oxygen. As a result, more oxygen radicals are formed, which damage membrane structures and respiratory chain complexes. Apart from a directly harmful effect of the oxygen radicals, the reduced ATP formation also has serious consequences that promote the further progression of the disease. In the area of the macula, the effect of the concentrated light requires an intensive repair capacity, which is particularly dependent on the availability of energy in the form of ATP. Impaired respiratory chain function ultimately results in a decreased ability to repair photodamage, further deteriorating vision. The influence of micronutrients on the pathogenesis of AMD There is currently no way to treat AMD causally. However, promising studies have shown that the progression of the disease can be stopped or at least slowed down by micronutrients that support antioxidant, anti-inflammatory and mitochondrial function. It could even be shown that micronutrients such as coenzyme Q10, acetyl-L-carnitine, omega-3 fatty acids and lutein can significantly improve vision in people with AMD. Coenzyme Q10 Coenzyme Q10 (ubiquinone) is a quinone with a side chain consisting of 10 isoprene-units that transfers electrons between respiratory chain complexes and can enhance energy production. the antioxidant capacity of the tissues decreases, while the load from oxygen radicals increases. The positive effect of coenzyme Q10 supplementation was confirmed in a clinical study in which 106 participants Coenzyme Q10-content (nmol/g dry weight) 60 50 40 30 20 10 0 ≤ 10 Years Content retina Content choroid ≥ 90 Years Fig. 4: The coenzyme Q10 content of the retina and the choroid lying under the retina decreases with increasing age. 28 No. 1 April/May 2022
AMD and micronutrients with AMD received either a dietary supplement with acetyl-L-carnitine, omega-3 fatty acids and coenzyme Q10 or a placebo. While the visual performance in the placebo group deteriorated significantly in the following 12 months, the participants in the verum group showed a significant improvement in visual functions. (3) Acetyl-L-Carnitine Carnitine is formed from the amino acids lysine and methionine and plays an essential role in the transport of long-chain fatty acids into the mitochondria. In its acetylated form, carnitine can more easily cross cell membranes and act inside the cell. Acetyl- L-carnitine improves mitochondrial energy production and reduces lipofuscin deposition by promoting fat metabolism. In AMD, supplementation together with coenzyme Q10 and omega-3 fatty acids can significantly improve visual parameters and slow down disease progression. (3) Omega-3 fatty acids Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are polyunsaturated fatty acids that belong to the group of omega-3 fatty acids and form structural components of cell membranes. In the eye, high concentrations of DHA are stored in the outer segments of the photoreceptor cells. Omega-3 fatty acids have a beneficial effect on membrane fluidity and the function of membrane-associated proteins. This makes the membranes of the blood cells more flexible. They can pass through the narrow capillaries of our blood vessels more easily and improve tissue oxygenation. In AMD, supplementation with omega-3 fatty acids can significantly improve antioxidant capacity. A clinical study with 172 participants was also able to show a positive influence on the optical density of the macular pigment and a significantly beneficial effect on blood lipid levels. (4) Lutein The carotenoids lutein and zeaxanthin are stored in high concentrations in the macula. They filter out large portions of the high-energy blue-violet light and serve as “natural sunglasses” that mitigate the harmful effects of the radiation. With a reduced carotenoid content in the macula, there is both an increased harmful effect of the lipofuscin deposits and increased exposure to light, which particularly Expert in health ingredients and innovative formulations www.seanova.fr contact@seanova.fr +33(0)2 98 50 41 60 // No. 1 April/May 2022 29
