Age-related macular degeneration and macular telangiectasia caused by dysfunctional energy metabolism: Study
Age-related macular degeneration (AMD) and macular telangiectasia may be caused by dysfunctional energy metabolism. Both eye diseases develop from abnormal growth of blood vessels in the eye, which is believed to be triggered by oxygen deprivation. Now the researchers suggest another cause, dysfunctional energy metabolism in the eye, resulting in insufficient energy resources available for the light receptors in the retina.
Senior investigator Lois Smith explained, “They have the highest concentration of mitochondria — the “furnace” of the cell — and use more energy than any other cell in the body. They have to be ‘on call’ all the time to signal light perception and have to recycle their components constantly.”
To explore the resulting fuel starvation, Smith created mouse models in which fatty acids were manipulated so that photoreceptors were unable to get either lipids or glucose. “When blood lipids are elevated, the lipid sensor says, ‘we don’t need glucose, we have enough lipids here,’ and it shuts off glucose uptake inappropriately,” Smith explained.
Energy-starved photoreceptors call for new blood vessels to bring in nutrients by secreting large amounts of vascular endothelial growth factor (VEGF). This signaling protein is known to encourage abnormal blood-vessel formation in macular disease.
VEGF blockers can be used to treat AMD but are associated with certain side effects. The researchers will now explore whether people have lipid sensors similar to those in mice. If this is the case, existing inhibitors could be tried in clinical trials.
Age-relate macular degeneration reversed with laser treatment
Age-related macular degeneration (AMD) in its early stages may be reversed with laser treatment. Researcher Erica L. Fletcher explained, “It is hoped that this study will provide a basis for the clinical use of the low energy nanosecond laser in those with early stage age-related macular degeneration and that such a treatment will limit the progression of the disease to the advanced, sight-threatening forms.”….
Source: Bel Marra Health