Environmental activation of a hypothalamic BDNF-adipocyte IL-15 axis regulates adipose-natural killer cells.
Brain Behav Immun
; 95: 477-488, 2021 07.
Article
in En
| MEDLINE
| ID: mdl-33989745
ABSTRACT
Physical and social environments influence immune homeostasis within adipose tissue, yet the mechanisms remain poorly defined. We report that an enriched environment (EE) housing modulates the immune cell population in white adipose tissue of mice including an increase in the abundance of natural killer (NK) cells. EE upregulates the expression of IL-15 and its receptor IL-15Rα specifically within mature adipocytes. Mechanistically, we show that hypothalamic brain-derived neurotrophic factor (BDNF) upregulates IL-15 production in adipocytes via sympathetic ß-adrenergic signaling. Overexpressing BDNF mediated by recombinant adeno-associated virus (rAAV) vector in the hypothalamus expands adipose NK cells. Conversely, inhibition of hypothalamic BDNF signaling via gene transfer of a dominant negative TrkB receptor suppresses adipose NK cells. In white adipose tissue, overexpression of IL-15 using an adipocyte-specific rAAV vector stimulates adipose NK cells and inhibits the progression of subcutaneous melanoma, whereas local IL-15 knockdown blocks the EE effect. These results suggest that bio-behavioral factors regulate adipose NK cells via a hypothalamic BDNF-sympathoneural-adipocyte IL-15 axis. Targeting this pathway may have therapeutic significance for cancer.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Killer Cells, Natural
/
Adipocytes
/
Brain-Derived Neurotrophic Factor
/
Interleukin-15
Limits:
Animals
Language:
En
Journal:
Brain Behav Immun
Journal subject:
ALERGIA E IMUNOLOGIA
/
CEREBRO
/
PSICOFISIOLOGIA
Year:
2021
Type:
Article
Affiliation country:
United States