The Scary Consequences of Obesity Caused By High-Fat Diet After Weight Loss
Obesity has been associated with age-related macular degeneration, a neuroinflammatory condition that is a leading cause of permanent blindness in older adults.
But it’s not clear how being overweight makes someone more likely to get the disease.
The long-term effect of being overweight on the immune response later in life is also unknown. This may be related.
New research has found that a history of obesity caused by a high-fat diet can lead to changes in innate immunity that promote inflammatory disease. These changes persist even after weight loss and a return to normal metabolism, according to a study conducted in mice. The findings suggest that the impacts of obesity can have long-lasting effects on the body’s immune system and overall health.
If these results are replicated in people, the authors hypothesize that these epigenetic modifications may contribute to the vulnerability to age-related neuroinflammatory disorders linked to obesity.
Obesity has been associated with age-related macular degeneration, a neuroinflammatory condition that is a leading cause of permanent blindness in older adults.
But it’s not clear how being overweight makes someone more likely to get the disease.
The long-term effect of being overweight on the immune response later in life is also unknown. This may be related.
Masayuki Hata and colleagues demonstrate in a series of mouse tests that adipose tissue macrophages from mice given a high-fat diet display epigenetic alterations that result in enhanced expression of genes involved in inflammatory responses.
According to the scientists, this expression persisted even when mice reached their pre-obesity weights and metabolic rates reverted to normal.
Hata et al. say that these long-lasting epigenetic changes happened when macrophages in adipose tissue were changed by fatty acids like steric acid toward a proinflammatory phenotype. This phenotype stays with the cells as they age.
These circulating inflammatory cells cause age-related macular degeneration by setting off an inflammatory response in the eye.
In a related Perspective, Kevin Mangum and Katherine Gallagher note that “The study by Hata et al. raises important questions about the upstream pathways that are responsible for epigenetic reprogramming in macrophages and whether targeting these pathways can reverse epigenetic changes.”
Source: 10.1126/science.abj8894
Image Credit: Getty