Hesperetin reverses some liver-aging signs in older mice

At 21 months old, healthy male mice began a five-month diet experiment. In the lab, one group received hesperetin—a flavonoid naturally found in citrus—at 100 mg/kg/day, while a control group received a neutral diet. By the end, the treated animals showed fewer signs of age-related liver damage, including fatty liver, inflammation and scar tissue.

The liver’s molecular age shifted too. Sequencing measured the activity of more than 10,000 genes at once, comparing young mice with untreated and hesperetin-treated older mice. The compound moved the aged liver toward a younger profile, reversing about 24% of age-linked gene-expression changes. Mitochondria and the cell machinery responsible for folding proteins also recovered toward a healthier state, while blood markers of liver damage moved closer to normal.

The team identified a mechanism rather than simply an association. Hesperetin stabilized Hmgcs2, enabling it to interact with Pparα; together, they activated production of Cisd2, a protective gene involved in mitochondrial health and cellular balance. Removing Cisd2 specifically from liver cells made hesperetin much less effective, pointing to Cisd2 as the main driver of the repair seen in the mice.

The biology has a human signal, but not yet a human result. In nontumor liver tissue from 80 surgical patients, PPARα and CISD2 both declined with age, and higher PPARα levels tracked with higher CISD2 levels. That finding supports the pathway described in the mouse work, while stopping short of showing that hesperetin benefits patients.

So what changes, concretely? The study offers a route toward a drug or carefully tested nutraceutical for age-related fatty liver disease, rather than a reason to prescribe more citrus. The researchers explicitly make no claim that eating citrus fruit will produce the same effect. The result remains a laboratory finding in aged mice, and no human treatment benefit has been established.