Lactate produced by alveolar type II cells suppresses inflammatory alveolar macrophages in acute lung injury

© 2023 Federation of American Societies for Experimental Biology..

Alveolar inflammation is a hallmark of acute lung injury (ALI), and its clinical correlate is acute respiratory distress syndrome-and it is as a result of interactions between alveolar type II cells (ATII) and alveolar macrophages (AM). In the setting of acute injury, the microenvironment of the intra-alveolar space is determined in part by metabolites and cytokines and is known to shape the AM phenotype. In response to ALI, increased glycolysis is observed in AT II cells, mediated by the transcription factor hypoxia-inducible factor (HIF) 1α, which has been shown to decrease inflammation. We hypothesized that in acute lung injury, lactate, the end product of glycolysis, produced by ATII cells shifts AMs toward an anti-inflammatory phenotype, thus mitigating ALI. We found that local intratracheal delivery of lactate improved ALI in two different mouse models. Lactate shifted cytokine expression of murine AMs toward increased IL-10, while decreasing IL-1 and IL-6 expression. Mice with ATII-specific deletion of Hif1a and mice treated with an inhibitor of lactate dehydrogenase displayed exacerbated ALI and increased inflammation with decreased levels of lactate in the bronchoalveolar lavage fluid; however, all those parameters improved with intratracheal lactate. When exposed to LPS (to recapitulate an inflammatory stimulus as it occurs in ALI), human primary AMs co-cultured with alveolar epithelial cells had reduced inflammatory responses. Taken together, these studies reveal an innate protective pathway, in which lactate produced by ATII cells shifts AMs toward an anti-inflammatory phenotype and dampens excessive inflammation in ALI.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:37

Enthalten in:

FASEB journal : official publication of the Federation of American Societies for Experimental Biology - 37(2023), 12 vom: 20. Dez., Seite e23316

Sprache:

Englisch

Beteiligte Personen:

Roy, René M [VerfasserIn]
Allawzi, Ayed [VerfasserIn]
Burns, Nana [VerfasserIn]
Sul, Christina [VerfasserIn]
Rubio, Victoria [VerfasserIn]
Graham, Jessica [VerfasserIn]
Stenmark, Kurt [VerfasserIn]
Nozik, Eva S [VerfasserIn]
Tuder, Rubin M [VerfasserIn]
Vohwinkel, Christine U [VerfasserIn]

Links:

Volltext

Themen:

33X04XA5AT
Acute lung injury
Acute respiratory distress syndrome
Alveolar epithelium
Alveolar macrophage
Anti-Inflammatory Agents
Cytokines
Glycolysis
Hypoxia-inducible factor
Journal Article
Lactate
Lactic Acid
Lipopolysaccharides
Research Support, N.I.H., Extramural
Research Support, N.I.H., Intramural
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 22.11.2023

Date Revised 07.03.2024

published: Print

Citation Status MEDLINE

doi:

10.1096/fj.202301722R

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM364752882