Nerve-associated adipose macrophages appear to help restrain aging-related visceral fat inflammation and lipolysis defects.
Evidence
This mouse lifespan study used intravascular labeling, single-cell sequencing, flow cytometry, and CD169 nerve-associated macrophage depletion to map resident and test aged visceral adipose function.
Caveat
The functional evidence comes from mouse CD169 nerve-associated macrophage depletion in visceral adipose tissue, so human relevance and other fat depots remain untested.
Simplified
Age-related inflammation or '' increases disease burden and controls lifespan. (ATMs) are critical regulators of inflammaging; however, the mechanisms involved are not well understood in part because the molecular identities of niche-specific ATMs are unknown. Using intravascular labeling to exclude circulating myeloid cells followed by single-cell sequencing with orthogonal validation via multiparametric flow cytometry, we define sex-specific changes and diverse populations of resident ATMs through lifespan in mice. Aging led to depletion of vessel-associated macrophages, expansion of lipid-associated macrophages and emergence of a unique subset of CD38age-associated macrophages in visceral adipose tissue with inflammatory phenotype. Notably, CD169CD11cATMs are enriched in a subpopulation of nerve-associated macrophages (NAMs) that declines with age. Depletion of CD169NAMs in aged mice increases inflammaging and impairs lipolysis suggesting in visceral adipose tissue. Our findings reveal NAMs are a specialized ATM subset that control adipose homeostasis and link inflammation to tissue dysfunction during aging. + + -+
Key numbers
16-fold
Increase in Monocytes
Observed in aged -DTR mice after NAM depletion.
from 1% to nearly 20%
Expansion of AAMs
AAMs increased in aged male mice.
Full Text
We can’t show the full text here under this license.