María Ángeles García-López, Alfonso Mora, Patricia Corrales, Tirso Pons, Ainhoa Sánchez de Diego, Amaia Talavera Gutiérrez, Karel H. M. van Wely, Gema Medina-Gómez, Guadalupe Sabio, Carlos Martínez-A, & Thierry Fischer.

The prevalence of overweight and obesity continues to rise in the population worldwide. Because it is an important predisposing factor for cancer, cardiovascular diseases, diabetes mellitus, and COVID-19, obesity reduces life expectancy. Adipose tissue (AT), the main fat storage organ with endocrine capacity, plays fundamental roles in systemic metabolism and obesity-related diseases. Dysfunctional AT can induce excess or reduced body fat (lipodystrophy). Dido1 is a marker gene for stemness; gene-targeting experiments compromised several functions ranging from cell division to embryonic stem cell differentiation, both in vivo and in vitro.

Reduced  body temperature in mutant ΔNT mice.
Reduced body temperature in mutant ΔNT mice (Image: Alfonso Mora).

We report that mutant mice lacking the DIDO N terminus show a lean phenotype. This consists of reduced AT and hypolipidemia, even when mice are fed a high-nutrient diet. DIDO mutation caused hypothermia due to lipoatrophy of white adipose tissue (WAT) and dermal fat thinning. Deep sequencing of the epididymal white fat (Epi WAT) transcriptome supported Dido1 control of the cellular lipid metabolic process. We found that, by controlling the expression of transcription factors such as C/EBPα or PPARγ, Dido1 is necessary for adipocyte differentiation, and that restoring their expression reestablished adipogenesis capacity in Dido1 mutants.

Our model differs from other lipodystrophic mice and could constitute a new system for the development of therapeutic intervention in obesity.