In a recent study published in the journal Cell, researchers analyzed the association between human longevity to growth and metabolic pathways.
There has been much research into the relationship between nutrients and cellular responses in humans. There is, however, a need for extensive research to determine the quantity, types, and combinations of nutrients that can promote healthy longevity.
The researchers explored the impact of specific nutrients on response pathways responsible for regulating diseases and aging in humans.
The protein-endocrine axis
Diets comprising increased protein and amino acid levels, such as methionine, were the most effective in improving growth hormone (GH) signaling as well as insulin-like growth factor 1 (IGF-1) levels. This, in turn, reduced the lifespan in rodents by stimulating a pro-aging axis, including increasing the circulating IGF-1 levels. Notably, the levels of IGF-1 in individuals consuming high-protein diets than those reporting low-protein diets. In addition, mutations in the GH and GH receptor that reduced growth gene levels led to extended lifespans of 35% to 40%.
Notably, deficiencies of both GH and GH receptors (GHR) reduced the levels of circulating IGF-1, which served as the main promoter of growth in humans. This stark decline and the reduced insulin levels due to lowered GHR levels could lead to a reduction in GHR signaling, which subsequently results in an extension of longevity. Remarkably, it is observed that in comparison to wild-type mice, mice having one lesser copy of the IGF-1R gene lived 16% to 33% longer, while mice with insulin receptor substrate 1 (IRS-1) mutations also lived 16% to 30% longer.