Longevity Hormone Can Preserve The Immune System

Increasing levels of hormone FGF-21 extends lifespan in mice by 40% and protects the immune system from decline

Aging is a complex phenomenon linked to many processes and failures occurring across the body, but a universal burden of advancing age is weaker immune system. You can blame that on your thymus, which shrivels, gains fatty tissue and loses its ability to field fresh armies of T Cells as you age.

Losing your adaptive immune system

Naive T Cells built in the thymus are a primary defence against a new enemy, and as the number of these fresh T cells withers away, you're left vulnerable to pathogens you've never been exposed to before. This is bad news for the annual flu bout and many other diseases that the young can brush off with a merely a sniffle.

Credit: The Thymistem project, currently researching stem cell therapies to repair the aging thymus

Enter FGF-21

FGF-21, also known as fibroblast growth factor 21, has been shown to extend the lives of mice up to 40%, and a team at Yale has discovered it can protect against immune system deterioration too. When mice engineered to be deficient in the hormone were compared to those with raised activity, the hormone was able to protect mice from age-related decline. 

"Elevating the levels of FGF21 in the elderly or in cancer patients who undergo bone marrow transplantation may be an additional strategy to increase T cell production, and thus bolster immune function" 

FGF-21 is secreted by the liver when food is scarce, allowing you to burn more fats in response to low glucose. Because of this FGF-21 is also an 'anti-diabetes' hormone, increasing insulin sensitivity and could potentially treating harmful levels of obesity. 

"We will also look to developing a way to mimic calorie restriction to enhance immune function without actually reducing caloric intake"

It's not well understood exactly how FGF-21 is protecting the thymus from deteriorating, but further exploration will establish whether raising FGF-21 levels by pharmacological intervention could be beneficial.

Read more at MedicalXpress