# Circadian feeding promotion by Ninjin’yoeito counteracts frailty in aged mice

## TL;DR

A herbal medicine called Ninjin’yoeito helps reduce frailty in old mice by promoting feeding during a specific time of day.

## Contribution

The study identifies pre-active phase feeding promotion as a novel strategy to counteract aging-related frailty.

## Key findings

- NYT increases food intake in aged and young mice during the pre-active phase (18:00–20:00).
- NYT improves anti-anxiety behavior, memory, and grip strength in aged mice.
- The effects of NYT are blocked when food is restricted during the pre-active phase.

## Abstract

Frailty in aging is a major health challenge, requiring solution. Older people with frailty often exhibit malnutrition and dysregulated feeding. Feeding behavior displays circadian rhythm, while aging and frailty involve rhythm disorders, suggesting possible role of circadian feeding in frailty and treatment. Herbal medicine, Ninjin’yoeito (NYT), reportedly ameliorates frail symptoms. The present study explored impacts of NYT on circadian feeding and psychological/physical functions in aged mice. Here, we report that oral NYT independent of administration timing increases food intake specifically in 18:00–20:00, the pre-active phase, in aged and young mice, an effect mimicked by Chenpi and hesperidin. NYT altered appetite-regulating hormones and neuropeptides in pre-active phase. Repeated NYT administration restored anti-anxiety behavior, memory, and grip strength that declined in aged mice. These effects were blocked by food deprivation and pair-fed to control selectively in 18:00–20:00. These results reveal pre-active phase feeding promotion as a novel avenue to intervene aging-related frailty.

•Circadian feeding promotion by Ninjin’yoeito (NYT) counteracts frailty in old mice.•Critical circadian time for feeding to counteract frailty is the pre-active phase.•NYT alters neurohormones regulating appetite and mind in pre-active phase.•Boosting early morning appetite and breakfast can intervene frailty in old people.•It can be achieved with NYT as medicine and Chenpi/hesperidin as food/supplement.

Circadian feeding promotion by Ninjin’yoeito (NYT) counteracts frailty in old mice.

Critical circadian time for feeding to counteract frailty is the pre-active phase.

NYT alters neurohormones regulating appetite and mind in pre-active phase.

Boosting early morning appetite and breakfast can intervene frailty in old people.

It can be achieved with NYT as medicine and Chenpi/hesperidin as food/supplement.