BIOLOGICAL RHYTHM RESEARCH, cilt.57, sa.5, ss.1-14, 2026 (SCI-Expanded, Scopus)
Obesity-related metabolic dysfunction is closely associated with impaired adipose tissue thermogenic capacity; however, the combined effects of time-restricted feeding (TRF) and exercise on thermogenesis-related signaling pathways remain incompletely understood. Therefore, we examined the impact of TRF and low-intensity exercise on the irisin – PGC-1α–UCP-1 axis in a high-fat diet (HFD) – induced obesity mouse model. Male C57BL/6 mice (n = 40) were fed HFD for 20 weeks to induce obesity and subsequently assigned to control, obese, obese+TRF, obese+exercise, or obese+TRF+exercise groups for 8 weeks. Circulating irisin, PGC-1α, and UCP-1 levels were measured using ELISA. Serum irisin levels were significantly elevated in obese and intervention groups compared with controls, with no further increase observed under combined TRF and exercise. PGC-1α levels showed significant group differences, reaching the highest values in the combined intervention group. In contrast, serum UCP-1 levels did not differ significantly among groups, although numerically higher values were observed following TRF and exercise. These findings suggest that TRF and exercise differentially influence circulating thermogenesis-related biomarkers and may modulate components of the irisin – PGC-1α–UCP-1 axis under sustained obesogenic conditions.