N,N-Dimethylacetamide Significantly Attenuates LPS- and TNFα-Induced Proinflammatory Responses Via Inhibition of the Nuclear Factor Kappa B Pathway

Abstract

Previously, we have shown that N,N-dimethylacetamide (DMA) prevents inflammation-induced preterm birth in a murine model, inhibits lipopolysaccharide (LPS)-induced increases in placental proinflammatory cytokines and upregulates the antiinflammatory cytokine interleukin-10 (IL-10). However, DMA's mechanism of action remains to be elucidated. In the current study, we investigate how DMA produces its antiinflammatory effect. Using in vitro and ex vivo models, we show that DMA suppresses secretion of proinflammatory cytokines in lipopolysaccharide (LPS)-induced RAW 264.7 cells, TNFα-challenged JEG-3 cells and LPS-stimulated human placental explants. DMA significantly attenuated secretion of TNFα, IL-6, IL-10 and granulocyte macrophage colony stimulating factor (GM-CSF) from LPS-stimulated RAW 264.7 cells; IL-6 secretion from TNFα-stimulated JEG-3 cells; and TNFα, IL-6, IL-10, GM-CSF and Interleukin-8 (IL-8) from LPS-stimulated human placental explants. We further investigated whether DMA's effect on cytokine expression involves the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. DMA (10 mM) significantly inhibited degradation of nuclear factor of kappa light polypeptide gene enhancer in B cell inhibitor α (IκBα) in LPS-stimulated RAW 264.7 cells, but there was no significant change in the expression of phosphorylated or native forms of downstream proteins in the MAPK pathway. In addition, DMA significantly attenuated luciferase activity in cells co-transfected with NF-κB-Luc reporter plasmid, but not with AP-1-Luc or CEBP-Luc reporters. Overall, our findings suggest that the antiinflammatory activity of DMA is mediated by inhibition of the NF-κB pathway via decreased IκBα degradation.

17-α Hydroxyprogesterone Nanoemulsifying Preconcentrate-Loaded Vaginal Tablet: A Novel Non-Invasive Approach for the Prevention of Preterm Birth

“…When DMA was added along with the MCT, the decrease in TNF-α was found to be 60%, showing that DMA further decreased the release of TNF-α. Our results are in agreement with previously reported results showing that DMA inhibits TNF-α release [24,25]. The reduction of cytokine release produced by the MCT and DMA may further enhance the formulation’s efficacy in preventing PTB.…”

Anti-inflammatory effect of diterpenes-enriched fractions from Pterodon polygalaeflorus through inhibition of macrophage migration and cytokine production

“…Also, proinflammatory cytokines, such as IL‐1β and TNF‐α, stimulate iNOS expression through NF‐κB . Inhibition of the NF‐κB pathway can be considered as a possible mechanism for reducing cytokine expression and NO production, as previously described with LPS‐stimulated RAW 264.7 cells . The reduction in these cytokine levels in LPS‐stimulated macrophage, by Fr3 and Fr4, may also be related to inhibition of p38 MAPK as this kinase inhibition has been related to the inhibition mechanism of IL‐β 1 and TNF‐α production for the diterpene lobolide .…”

“…The present study showed that the reduction of IL‐1 β, TNF‐α, IL‐10 and iNOS, in LPS‐stimulated RAW 264.7 macrophages, is probably due to, among other effects, the inhibition of the expressions of these proteins at the mRNA level. Also, proinflammatory cytokines, such as IL‐1β and TNF‐α, stimulate iNOS expression through NF‐κB . Inhibition of the NF‐κB pathway can be considered as a possible mechanism for reducing cytokine expression and NO production, as previously described with LPS‐stimulated RAW 264.7 cells .…”

Sodium Hydrogen Exchanger Regulatory Factor-1 (NHERF1) Regulates Fetal Membrane Inflammation

“…NF-kB is a pleiotropic transcription factor that increases proinflammatory cytokine production, and regulation of its activation is therefore considered one of the approaches to reduce the risk of PTB [ 33 , 34 , 35 ]. Novel therapeutics that reduce inflammation by inhibiting NF-kB using anti-inflammatory drugs [ 36 , 37 , 38 ], cell-penetrating peptides, small molecule inhibitors [ 33 , 39 , 40 ], nonspecific inhibitors [ 41 , 42 , 43 , 44 ], and flavonoids are now being tested [ 45 , 46 ]. However, very few have made it to clinical trials so far and none are in use clinically, likely due to several issues including, but not limited to, the mode of delivery, placental permeability, teratogenicity, and transgenerational effects.…”