PGE2 accounts for bidirectional changes in alveolar macrophage self-renewal with aging and smoking.
Life Sci Alliance
; 3(11)2020 11.
Article
en En
| MEDLINE
| ID: mdl-32820026
ABSTRACT
Alveolar macrophages (AMs) are resident immune cells of the lung that are critical for host defense. AMs are capable of proliferative renewal, yet their numbers are known to decrease with aging and increase with cigarette smoking. The mechanism by which AM proliferation is physiologically restrained, and whether dysregulation of this brake contributes to altered AM numbers in pathologic circumstances, however, remains unknown. Mice of advanced age exhibited diminished basal AM numbers and contained elevated PGE2 levels in their bronchoalveolar lavage fluid (BALF) as compared with young mice. Exogenous PGE2 inhibited AM proliferation in an E prostanoid receptor 2 (EP2)-cyclic AMP-dependent manner. Furthermore, EP2 knockout (EP2 KO) mice exhibited elevated basal AM numbers, and their AMs resisted the ability of PGE2 and aged BALF to inhibit proliferation. In contrast, increased numbers of AMs in mice exposed to cigarette smoking were associated with reduced PGE2 levels in BALF and were further exaggerated in EP2 KO mice. Collectively, our findings demonstrate that PGE2 functions as a tunable brake on AM numbers under physiologic and pathophysiological conditions.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Macrófagos Alveolares
/
Subtipo EP2 de Receptores de Prostaglandina E
Límite:
Animals
Idioma:
En
Revista:
Life Sci Alliance
Año:
2020
Tipo del documento:
Article
País de afiliación:
Estados Unidos