Key Finding: Researchers at City of Hope have identified a new type of stem cell, named committed preadipocytes, age-specific (CP-As) , that appears during aging and may contribute to increased abdominal fat. The study was published in the journal Science.
Background
Age-related abdominal fat accumulation occurs even when body weight remains stable. Prior knowledge attributed this to enlargement of existing fat cells, but the study suggests a significant role for new fat cell formation.
Experimental Evidence
- Adipocyte progenitor cells (APCs) from older mice, when transplanted into young mice, produced large numbers of new fat cells.
- APCs from young mice, when transplanted into older mice, produced relatively few new fat cells.
- Single-cell RNA sequencing revealed that APCs are relatively inactive in young mice but become highly active in middle-aged mice.
- In middle-aged mice, some APCs transformed into CP-As, a newly identified stem cell population that efficiently produces fat cells.
- The leukemia inhibitory factor receptor (LIFR) signaling pathway was found to be crucial for CP-A proliferation and fat cell development in older mice but not in young mice.
- Human tissue samples contained cells similar to CP-As, with higher numbers in middle-aged individuals, suggesting a comparable process in humans.
Potential Implications
Targeting CP-A cells or LIFR signaling could lead to new therapies for preventing or reducing age-related abdominal fat and associated metabolic disorders such as type 2 diabetes and heart disease.
Further Research
Future studies will track CP-A cells in animals, investigate their behavior in humans, and explore methods to block or eliminate them.