In laboratory mice, the absence of a single immune-produced protein, Granzyme K, was associated with hearts, livers and kidneys that aged more gracefully than those of their peers. The work, carried out by researchers at Monash University and published in the journal Immunity, touches a question people have long asked about the body: whether the immune system's slow decline must drag the organs down with it. Its answer, for now, is tentative, and the animals studied lived their entire lives without the protein, leaving open whether the same protection could be won by stepping in later. What it
Protein Granzyme K Linked to Age-Related Organ Damage in Mice, Opening New Research Path
It gives researchers a new target, not yet a treatment
Mark
So what did the Monash team actually find?
Mimi
Older mice that lacked Granzyme K had better heart function and less fibrosis, which is scarring that hampers an organ. They also showed less age-related damage in the liver and kidneys.
Mark
Granzyme K comes from immune cells, right?
Mimi
Yes, and its levels rise with age in both mice and humans. What wasn't clear was whether it actually contributes to organ damage.
Mark
What did the researchers find most striking?
Mimi
The organs looked less aged even though the immune systems of those mice kept ageing normally. Professor La Gruta said that challenges the idea that organ and immune ageing are inseparable.
Luke
Worth being clear on what that rests on, though. The mice never had the protein at all, their whole lives. That's not the same as treating an older animal.
Mimi
Right, and Professor La Gruta says so herself. They now need to learn whether blocking it later in life helps.
Mark
And the human data? It showed higher levels in heart failure and lupus nephritis.
Luke
Which is an association. The source says it warrants investigation but doesn't show that targeting the protein would prevent damage in people.
Mimi
So it's a new target, not a treatment.
Luke
And nothing yet on a timeline or a drug. Those details simply aren't in the reporting.
Il Polso
- Older mice that never produced Granzyme K kept stronger heart function and showed less scarring than mice that did.
- Their livers and kidneys also aged more slowly, even though their immune systems aged on the normal schedule.
- The finding cuts against the long-held belief that immune aging and organ aging move in lockstep, unsettling a familiar assumption.
- Human data hint at raised Granzyme K levels in heart failure and lupus nephritis, but that link has not yet been proven to cause harm.
- Researchers are now developing ways to block the protein selectively, testing whether late-life blocking can deliver the same benefits.
In laboratory mice, the absence of a single immune-produced protein, Granzyme K, was associated with hearts, livers and kidneys that aged more gracefully than those of their peers. The work, carried out by researchers at Monash University and published in the journal Immunity, touches a question people have long asked about the body: whether the immune system's slow decline must drag the organs down with it. Its answer, for now, is tentative, and the animals studied lived their entire lives without the protein, leaving open whether the same protection could be won by stepping in later. What it offers is a new place to look, not yet a remedy.
Mice raised without a protein called Granzyme K grew old with healthier hearts, livers and kidneys than mice that carried it. The study, from Monash University and published in the journal Immunity, gives researchers a fresh target in the long effort to age well.
Granzyme K is made by immune cells, and its levels rise with age in both mice and people. What remained unknown was whether it actually harms organs over time. The team compared older mice lacking the protein with older mice that had it, and the difference was clear. The animals without it had better heart function, less fibrosis, the scarring that can stiffen an organ and impair it, and fewer signs of damage in the liver and kidneys.
Professor Nicole La Gruta, the senior researcher, explained that organ aging can leave people more vulnerable to heart and kidney disease, and that Granzyme K appears to drive part of that damage. The detail that struck the team most was that these mice's immune systems aged normally, while their organs aged more slowly. That challenges the assumption that the two must decline together, and it suggests a new route to keeping organs healthy longer.
Human datasets showed elevated Granzyme K in patients with inflammatory and fibrotic conditions, including heart failure and lupus nephritis. Those findings merit follow-up, but they do not prove that blocking the protein would protect people.
The key caveat is that these mice lived without the protein from birth. The next question is whether blocking it later in life brings similar benefit, and the team is working on selective ways to do exactly that. Whether the results carry over to humans remains open. The discovery is not a treatment yet, but it marks a promising new direction.
Mice that never made a protein called Granzyme K grew old with healthier hearts, livers and kidneys than mice that did. That is the central result of a study from Monash University, published in the journal Immunity, and it is giving researchers a new target in the search for ways to age more healthily.
Granzyme K is produced by immune cells. Its levels are known to climb significantly with age, in both mice and humans. What no one had pinned down was whether the protein does anything to the organs as time passes. The Monash team set out to compare older mice lacking Granzyme K with older mice that had it.
The animals without the protein showed better heart function and reduced fibrosis, the scarring that can impair how well an organ works. They also showed fewer signs of age-related damage in the liver and kidneys. Professor Nicole La Gruta, the senior researcher, from the Monash Biomedicine Discovery Institute, said organs change with age in ways that can leave people more susceptible to diseases, including heart and kidney disease. In her words, Granzyme K plays an important role in driving some of that damage.
One detail stood out to the team. The organs of the mice without Granzyme K showed fewer signs of ageing even though their immune systems kept ageing normally. Professor La Gruta said this challenges the long-held assumption that organ ageing and immune ageing are inextricably linked. She described it as opening an exciting new avenue for developing treatments that could help people keep their organs healthier for longer.
The researchers also looked at human datasets. They found elevated Granzyme K levels in patients with several inflammatory and fibrotic diseases, including heart failure and lupus nephritis, a condition that affects the kidneys. Those findings warrant further investigation, but they do not establish whether targeting the protein would prevent organ damage in people.
There is a significant caveat built into the mouse work itself. These animals lived their whole lives without Granzyme K. Professor La Gruta said that means researchers now need to understand whether blocking the protein later in life could achieve similar benefits. Her team is investigating ways to selectively block it to test exactly that.
Whether the same benefits could be achieved in humans is a separate question, and she said further research is needed to answer it. The discovery does not yet offer a treatment. What it offers is a new target, and the next studies on late-life blocking will show whether it holds up.
Citazioni salienti
Because these mice have lived their entire lives without Granzyme K, we now need to understand whether blocking the protein later in life could achieve similar benefits.— Professor Nicole La Gruta, Monash Biomedicine Discovery Institute
Vuoi la storia completa?
Leggi l'originale su Have a Go News ↗