Why body fat ages faster than almost any other tissue — and the enzyme that holds it back
Fat tissue ages faster than most other parts of the body. Scientists have now identified the enzyme that keeps that process in check — and what goes wrong when it disappears.
A study published in Aging Cell examines an enzyme called Pck1, a core player in fat cell metabolism. Pck1 is best known for its role in gluconeogenesis — the process by which the liver and some other tissues produce glucose from non-sugar sources. But this research reveals a second, less recognised function: in adipose tissue, Pck1 suppresses the formation of senescent cells. Senescent cells — the so-called zombie cells that stop functioning normally but refuse to die — accumulate in fat tissue with particular speed as we age.
When Pck1 was switched off in fat cells in mouse models, senescent cell formation accelerated sharply. Cells stopped their normal functions earlier, became inflamed, and began secreting substances that damaged surrounding tissue. Insulin sensitivity also declined — an early sign of the metabolic disruption that leads, in humans, to type 2 diabetes and related conditions. The researchers’ conclusion: Pck1 is not just a metabolic enzyme, it is also a guardian against premature ageing of fat tissue.
Fat as the overlooked organ in ageing research
Adipose tissue is often underestimated in ageing research. Yet the study’s authors describe it as ‘one of the most vulnerable tissues’ in the body as we grow older — and for good reason. Fat is not a passive energy store. It is an active endocrine organ that secretes hormones and signalling molecules affecting the entire body. Aged fat tissue produces more pro-inflammatory substances and fewer protective hormones such as adiponectin. That shift contributes to the kind of low-grade chronic inflammation — sometimes called ‘inflammaging’ — increasingly linked to a wide range of age-related diseases.
What makes this research particularly interesting for longevity science is the potential link between metabolic activity and cellular ageing. It suggests that the decline in metabolism many people experience with age is not only a consequence of ageing, but also a cause: reduced Pck1 activity in fat cells may create a self-reinforcing cycle. Lower metabolic activity produces more senescent cells, which in turn further disrupt metabolism.
What this research does not tell us
It is tempting to jump to the conclusion that activating Pck1 could be a longevity therapy. But the study was conducted in mice, and translation to humans is far from guaranteed. Pck1 is also involved in multiple processes simultaneously — activating it without triggering off-target effects elsewhere in metabolism is not straightforward. The study identifies a mechanism, not a solution. Whether this pathway is therapeutically tractable is a question that will take years to answer.