The differentiation of human monocytes into macrophages is influenced by environmental signals. Here we asked in how far nicotinamide (NAM), a vitamin B3 derivative known to play a major role in nicotinamide adenine dinucleotide (NAD)-mediated signaling events, is able to modulate monocyte differentiation into macrophages developed in the presence of granulocyte macrophage colony-stimulating factor (GM-MO) or macrophage colony-stimulating factor (M-MO). We found that GM-MO undergo biochemical, morphological and functional modifications in response to NAM, whereas M-MO were hardly affected. GM-MO exposed to NAM acquired an M-MO-like structure while the LPS-induced production of pro-inflammatory cytokines and COX-derived eicosanoids were down-regulated. In contrast, NAM had no effect on the production of IL-10 or the cytochrome P450-derived eicosanoids. Administration of NAM enhanced intracellular NAD concentrations; however, it did not prevent the LPS-mediated drain on NAD pools. In search of intracellular molecular targets of NAM known to be involved in LPS-induced cytokine and eicosanoid synthesis, we found NF-kappaB activity to be diminished. In conclusion, our data show that vitamin B3, when present during the differentiation of monocytes into GM-MO, interferes with biochemical pathways resulting in strongly reduced pro-inflammatory features.
PubMed ID: 26385774
Publication type: Not specified
Journal: Innate Immun
Human Diseases: No Human Disease specified
Citation: Innate Immun. 2015 Nov;21(8):813-26. doi: 10.1177/1753425915602545. Epub 2015 Sep 18.
Date Published: 20th Sep 2015
Registered Mode: by PubMed ID
Created: 9th May 2019 at 14:44
Last updated: 7th Dec 2021 at 17:58