Back pain from spinal disc wear: a growth factor and a longevity protein slow the damage in rats
Spinal disc degeneration is one of the most common causes of chronic lower back pain in older people — and so far, there is little to offer beyond painkillers and surgery.
The intervertebral discs — the shock-absorbing cushions between the vertebrae of the spine — lose water, elasticity, and living cells as we age. The result is pain, stiffness, and in severe cases, nerve compression. It is a nearly universal feature of aging, and one of the most frequently targeted conditions in longevity research.
Researchers publishing in Aging Cell focused on two molecules: FGF21, a growth factor normally associated with fat metabolism and energy regulation, and SIRT1, an enzyme from the sirtuin family that has long been linked to aging and cellular health. Sirtuins are proteins that regulate a wide range of cellular processes — from DNA repair to metabolism — and their activity declines as we age. The study showed that FGF21 boosts SIRT1 expression in disc cells, and that this delayed the degeneration of intervertebral disc tissue in a rat model.
From fat metabolism to spinal discs
FGF21’s appearance here is surprising at first glance. This growth factor was originally studied for its role in insulin sensitivity and weight regulation. But FGF21 has receptors in many different tissues, and more recent research suggests it has broader protective effects throughout the body — beyond metabolism alone. The finding that it can influence disc health through SIRT1 adds a new dimension to this molecule’s potential applications.
The critical caveat is that this is a rodent model. Rats are not humans, and the translation from laboratory results to clinical use is rarely straightforward. Several previous promising interventions for disc degeneration have failed to make that leap. Still, this research fits into a growing body of work connecting SIRT1 and sirtuins more broadly to degenerative conditions associated with aging.
What it means for treatment
The study adds to a picture in which intervertebral disc degeneration is not purely mechanical wear, but also reflects a biological aging process that may be pharmacologically addressable. If confirmed in human cells or clinical trials, that would open a very different treatment landscape from the current options — which are largely limited to pain management, physiotherapy, or surgery in severe cases. Whether FGF21 or a derivative will ever play a role in treating back pain remains entirely open.