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Ethanol (EtOH)-induced TGF-?1 and reactive oxygen species production are necessary for EtOH-induced alveolar macrophage dysfunction and induction of alternative activation.

ABSTRACT: Previous studies have shown that chronic ethanol (EtOH) ingestion results in impaired alveolar macrophage function, increased TGF-?(1) production, and decreased antioxidant availability. Similarly, alternative activation (M2 activation) of alveolar macrophages also induces TGF-?(1) production and impairs macrophage function. However, the potential links between EtOH-induced alveolar macrophage derangements, M2 activation, TGF-?(1) production signaling, and oxidant stress have yet to be examined. We hypothesized that EtOH-induced oxidant stress and induction of TGF-?(1) signaling result in alternative activation which subsequently impairs the phagocytic capacity of alveolar macrophages.Primary rat alveolar macrophages and the alveolar macrophages cell line NR8383 were treated with 0.08% EtOH ± the antioxidant glutathione (GSH) or a TGF-?(1) neutralizing antibody for 5 days. Outcome measures included TGF-?(1) production, reactive oxygen species (ROS) production, phagocytic capacity, and expression of markers of M2 activation.Chronic EtOH treatment greatly decreased alveolar macrophage phagocytic function, increased ROS production, increased TGF-?(1) , and increased expression of markers of M2 activation. GSH supplementation and inhibition of TGF-?(1) signaling during EtOH treatment prevented these alterations.EtOH treatment increased oxidant stress, TGF-?(1) production, and alternative activation in NR8383 cells. However, GSH supplementation and ablation of TGF-?(1) signaling prevented these effects. This suggested that the EtOH-induced switch to an M2 phenotype was a result of decreased antioxidant availability and increased TGF-?(1) signaling. Preventing EtOH-induced induction of alternative activation may improve alveolar macrophage function in alcoholic subjects and decrease the risk of respiratory infections.

SUBMITTER: Brown SD

PROVIDER: S-EPMC3414680 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Ethanol (EtOH)-induced TGF-β1 and reactive oxygen species production are necessary for EtOH-induced alveolar macrophage dysfunction and induction of alternative activation.

Brown Sheena D SD Brown Lou Ann S LA

Alcoholism, clinical and experimental research 20120502 11

<h4>Background</h4>Previous studies have shown that chronic ethanol (EtOH) ingestion results in impaired alveolar macrophage function, increased TGF-β(1) production, and decreased antioxidant availability. Similarly, alternative activation (M2 activation) of alveolar macrophages also induces TGF-β(1) production and impairs macrophage function. However, the potential links between EtOH-induced alveolar macrophage derangements, M2 activation, TGF-β(1) production signaling, and oxidant stress ha ...[more]

PMID: 22551312

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Dataset Information

Ethanol (EtOH)-induced TGF-?1 and reactive oxygen species production are necessary for EtOH-induced alveolar macrophage dysfunction and induction of alternative activation.

Publications

Ethanol (EtOH)-induced TGF-β1 and reactive oxygen species production are necessary for EtOH-induced alveolar macrophage dysfunction and induction of alternative activation.

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