September 29, 2023

New Research Links Obesity to Blinding Eye Disease

Macular degeneration is a progressive eye illness that affects the central part of the retina, called the macula. It leads to a loss of main vision, making it tough to read, drive, and acknowledge faces.
A brand-new study from Canada, released in the popular journal Science, has clarified a potential molecular reason for age-related macular degeneration (AMD).
Research conducted at Hôpital Maisonneuve-Rosemont in Montreal has exposed how stress factors of every day life, such as obesity, can alter the body immune system and cause damage to the eye as it ages.
” We wished to know why some individuals with a hereditary predisposition develop AMD while others are spared,” said University of Montreal ophthalmology professor Przemyslaw (Mike) Sapieha, who led the research study with his postdoctoral fellow Dr. Masayuki Hata.

” Although substantial effort has been invested in comprehending the genes accountable for AMD, variations, and anomalies in susceptibility genes just increase the risk of establishing the disease, however do not trigger it,” Sapieha described.
” This observation suggests that we should get a much better understanding of how other factors such as environment and lifestyle contribute to disease development.”
AMD is a major reason for irreparable loss of sight around the world and affected approximately 196 million people in 2020. It comes in two kinds:

dry AMD, identified by the accumulation of fatty deposits at the back of the eye and the death of afferent neuron in the eye,
and damp AMD, which is identified by infected blood vessels that establish in the most delicate part of the sight-generating tissue, called the macula.

Contact with pathogens
It is currently understood that the body immune system in the eye of an individual with AMD becomes dysregulated and aggressive. Normally, immune cells keep the eye healthy, but contact with pathogens such as bacteria and infections can make them go awry.
At the exact same time, immune cells are likewise triggered when the body is exposed to stressors such as excess fat in weight problems, making being obese the top non-genetic risk factor for establishing AMD, after cigarette smoking.
In their study, Sapieha and Hata utilized obesity as a model to accelerate and exaggerate the stress factors experienced by the body throughout life.
They found that short-term obesity or a history of obesity leads to persistent changes in the DNA architecture within immune cells, making them more vulnerable to producing inflammatory molecules.
” Our findings supply crucial information about the biology of the immune cells that trigger AMD and will permit the advancement of more tailored treatments in the future,” stated Hata, now an ophthalmology teacher at Kyoto University, in Japan.
The scientists hope their discovery will lead other scientists to widen their interest beyond obesity-related illness to other diseases identified by increased neuroinflammation, including Alzheimers disease and several sclerosis.
Referral: “Past history of obesity activates persistent epigenetic changes in innate immunity and intensifies neuroinflammation” by Masayuki Hata, Elisabeth M. M. A. Andriessen, Maki Hata, Roberto Diaz-Marin, Frédérik Fournier, Sergio Crespo-Garcia, Guillaume Blot, Rachel Juneau, Frédérique Pilon, Agnieszka Dejda, Vera Guber, Emilie Heckel, Caroline Daneault, Virginie Calderon, Christine Des Rosiers, Heather J. Melichar, Thomas Langmann, Jean-Sebastien Joyal, Ariel M. Wilson and Przemyslaw Sapieha, 5 January 2023, Science.DOI: 10.1126/ science.abj8894.