# Granzyme K enzyme found to worsen age-related liver, kidney and heart damage in mice

- Published: 2026-11-14 17:52 UTC
- Section: Life & Health › Biology & biochemistry
- Tags: granzyme K, biological aging, age-related fibrosis, organ damage in mice, aging and immunity, Immunity journal, liver kidney heart aging, chronic inflammation
- URL: https://realtech.media/news/rt-046eaf4fc9d75d84acbe1d47_granzyme_k_enzyme/

**Authors of a mouse study in Immunity report that granzyme K damages organ tissue directly and does not drive the age-related decline of immunity.**

![Granzyme K enzyme found to worsen age-related liver, kidney and heart damage in mice](https://realtech.media/media/2026/11/6703f3887498de49.webp)
*zamin.uz*

Researchers have identified granzyme K, an enzyme that intensifies age-related damage to the liver, kidneys and heart, zamin.uz reports. The results were published in the journal Immunity. [1] The experiments were carried out on mice: genetically modified animals that lack the protein, and ordinary aged mice. [1]

## Aging organs and the immune system

Biological aging affects all body systems. Tissues gradually lose the ability to recover, cellular damage accumulates in them, and chronic inflammation develops. [1]

Until now, specialists considered age-related changes in internal organs and aging of the immune system to be closely linked. With age, immune cells work more slowly but release more substances that amplify inflammation. Granzyme K is one of them. [1] Biologists already knew that its concentration rises markedly in aged mice and in humans, but its exact function remained unknown. [1]

## Results in mice without granzyme K

The researchers used genetically modified mice that had no granzyme K from birth. In both groups, the modified and the ordinary aged mice, the ability to fight infections and tumors weakened to the same degree. [1]

In mice without the protein, age-related fibrosis (scarring) was markedly reduced. Liver damage was lower, the heart kept its normal thickness, and the amount of harmful proteins in the kidneys decreased. [1]

The authors concluded that granzyme K directly destroys the tissue of internal organs and makes it harder, but does not directly affect the age-related weakening of immunity. According to them, the aging of organs and the decline of immunity can thus be separated at the biological level. [1]

The authors note that the protein now offers a defined target for study. In their view, if drugs that block its activity in adults were developed, physicians might be able to protect the heart, kidneys and liver from age-related degeneration and fibrosis. Applying these results to humans fully, however, would require additional large-scale clinical studies. [1]

## Sources

1. [zamin.uz](https://zamin.uz/tibbiyot/227138-qarilikni-toxtatib-boladimi-jigar-va-yurakni-emiruvchi-ferment-fosh-etildi.html)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-046eaf4fc9d75d84acbe1d47_granzyme_k_enzyme/