The Effects of Obesity on Sex, Aging, and Cancer Development in a Longitudinal Study of High-Fat-Diet-Fed C3H/HeJ Mice

(1) Background: Few studies focus on the development of obesity as a chronic disease as opposed to an acute condition. The “general purpose” C3H/HeJ (C3H) mouse strain is an alternative model for obesity development with regards to sex disparities and non-predisposed populations over time. (2) Methods: In this study, 64 female and 64 male C3H mice were separated into two groups (n = 32) and maintained on a control or high-fat diet (HFD) for up to 18 months. At 6-month intervals, a cross-sectional cohort (n = ~8) was censored for evaluation. The mice were monitored for change in total, lean and fat mass, survivability, and tumor incidence. (3) Results: Both sexes in the C3H mouse strain developed diet-induced obesity (DIO). An increase in total mass consistent with a HF diet was observed in both female and male C3H mice. Survivorship at 18 months was the highest in the HF-diet-fed males (~62%) and lowest in the males fed the control diet (~19%). Females showed survivability at ~40%, regardless of diet. Cancer development increased more notably in the males with the HF diet and showed sex bias for liver cancer (males) and ovarian cancer (females) incidence with age. (4) Conclusions: This study establishes a baseline for future use of C3H mice as a strong model for studying obesity as a chronic disease, in both sexes, and as long-term model for age-related diet-induced obesity and cancer development.