# Exercise and time-restricted and/or dietary feeding jointly improve hepatic lipid homeostasis in diet-induced obese mice

## TL;DR

Combining exercise, time-restricted feeding, and diet helps reduce liver fat and improve liver function in obese mice.

## Contribution

The study reveals distinct and additive effects of combined lifestyle interventions on hepatic lipid composition and gene regulation.

## Key findings

- LFD led to the greatest weight loss and normalized liver enzyme levels.
- Combined interventions reduced liver damage markers even under high-fat diet conditions.
- LFD with TRF and/or TM decreased lipogenic gene expression and altered lipid composition.

## Abstract

Obesity and metabolic syndrome are associated with dysregulated hepatic lipid metabolism, contributing to metabolic dysfunction-associated steatotic liver disease (MASLD). Though lifestyle interventions such as a low-fat diet (LFD), treadmill (TM) exercise, and time-restricted feeding (TRF) reduce hepatic lipid accumulation, their combined effects on hepatic lipid composition and lipid metabolism-related gene regulation remain poorly understood. Here, we examined the individual and combined effects of LFD, TM, and/or TRF on liver function, comprehensive hepatic lipidomics, and lipid metabolism-related gene expression in diet-induced obese mice, thereby extending our previous work through detailed lipid class-specific analyses and assessment of interactive intervention effects. Among all interventions, LFD led to the greatest weight loss and normalized plasma aspartate aminotransferase (AST) as well as alanine aminotransferase (ALT) levels. Combined interventions, including TM and TRF, reduced markers of liver damage even under continued HFD conditions compared to HFD alone. LFD with TRF and/or TM decreased the expression of lipogenic genes (Srebf1, Lxrα, Apoe), while expression of genes further involved in lipid synthesis (Fasn and Hmgcr) tended to be increased when TM was combined with either LFD or HFD. β-oxidation-related genes (Ppara, Acox1, Cpt1a) were most downregulated in the LFD groups vs. the HFD + TM group, likely representing a metabolic adaptation to increased lipid mobilization. For the first time, lipidomics analysis demonstrated that in particular LFD alone or in combination with TM most effectively increased sphingomyelin (SM) and dihydrosphingomyelin (DHSM) as well as lysophosphatidylcholine (LPC) and phosphatidylcholine (PC), potentially reflecting compensatory lipid remodeling. Taken together, these findings highlight distinct and additive effects of combined lifestyle interventions on hepatic lipid composition and gene regulation, clearly delineating the novel contributions of the present study and supporting combined dietary and physical strategies as potential approaches to improve hepatic lipid homeostasis and mitigate MASLD development.

The online version contains supplementary material available at 10.1038/s41598-026-45394-4.