Acute Alcohol Inhibits the Induction of Nuclear Regulatory Factor ??B Activation Through CD14/Toll-Like Receptor 4, Interleukin-1, and Tumor Necrosis Factor Receptors: A Common Mechanism Independent of Inhibitory ??B?? Degradation?
Nuclear translocation and DNA binding of the nuclear factor kappaB (NF-kappaB) is an early event in inflammatory cell activation in response to stimulation with bacterial components or cytokines. Cell activation via different receptors culminates in a common pathway leading to NF-kappaB activation and proinflammatory cytokine induction. We have previously shown that acute alcohol inhibits NF-kappaB activation by lipopolysaccharide (LPS) in human monocytes. Here we investigated whether acute alcohol treatment of human monocytes also inhibits NF-kappaB when induced through activation of the interleukin (IL)-1 or tumor necrosis factor (TNF) receptors.
Human peripheral blood monocytes were treated with LPS, TNFalpha, and IL-1beta in the presence or absence of 25mM alcohol for 1 hr. NF-kappaB activation was determined by electrophoretic mobility shift assays using nuclear extracts. Inhibitory kappaB(alpha) (IkappaB(alpha)) was estimated by Western blotting in cytoplasmic extracts. Chinese hamster ovary cells expressing human CD14 were treated with LPS in the presence or absence of alcohol to study NF-kappaB and IkappaB(alpha) regulation.
Our results indicate that acute alcohol inhibits IL-1beta- and TNFalpha-induced NF-kappaB activation. We further show in CD14/toll-like receptor 4-expressing Chinese hamster ovary cells the specificity of alcohol-mediated inhibition of NF-kappaB via the toll-like receptor 4/CD14 receptors. Inhibition of NF-kappaB by acute alcohol was concomitant with decreased levels of the IkappaB(alpha) molecule in the cytoplasm of LPS, IL-1, and TNFalpha-activated monocytes.
These data suggest a unique, IkappaB(alpha)-independent pathway for the inhibition of NF-kappaB activation by acute alcohol in monocytes. Universal inhibition of NF-kappaB by acute alcohol via these various receptor systems suggests a target for the effects of alcohol in the NF-kappaB activation cascade that is downstream from IkappaB(alpha) degradation. Further, these results demonstrate that acute alcohol is a potent inhibitor of NF-kappaB activation by mediators of early (LPS) or late (IL-1, TNF(alpha)) stages of inflammation in monocytes.
"The reasons for the increased sepsis mortality in patients with AUD may partly be explained by the effects of alcohol on cytokine production. Patients with AUD are known to have altered expression of pro-inflammatory cytokines, including interleukin (IL) 6, tumor necrosis factor (TNF) α, and IL1β [14,16,19,20]. Similarly, anti-inflammatory cytokine (IL10) production has been found to be either elevated or decreased in surgical patients with AUD [15,19]. "
[Show abstract][Hide abstract] ABSTRACT: Patients with alcohol use disorders (AUD) are at increased risk of developing sepsis and have higher mortality. AUD are associated with higher cortisol and anti-inflammatory cytokine profile. Higher cortisol increases risk of death in septic patients. The relationship between AUD and cortisol in septic patients is unknown. We aimed to study this relationship and postulated that AUD would be associated with higher cortisol and anti-inflammatory cytokine profile.
This was a prospective cohort study of 40 medical intensive care unit (ICU) patients admitted with sepsis. Cortisol, anti-inflammatory interleukin (IL) 10, and pro-inflammatory IL1β, IL6, tumor necrosis factor (TNF) α were measured.
Thirteen (32%) out of 40 patients had AUD. AUD patients had higher cortisol by univariate (39 microg/dl versus 24, P = 0.04) and multivariable analyses (44 microg/dl versus 23, P = 0.004). By univariate analyses, AUD patients had higher IL10 (198 picog/dl versus 47, P = 0.02) and IL6 (527 picog/ml versus 156, P = 0.048), but similar IL1β and TNFα. By multivariable analyses, AUD patients had higher IL10 (182 picog/dl versus 23, P = 0.049) but similar IL1β, IL6, and TNFα. AUD patients had lower IL1β/IL10 (univariate 0.01 versus 0.10, P = 0.04; multivariable 0.01 versus 0.03, P = 0.04), lower TNFα/IL10 (univariate 0.15 versus 0.52, P = 0.03; multivariable 0.11 versus 0.63, P = 0.01), but similar IL6/IL10.
AUD are common diagnoses among medical ICU patients with sepsis. Patients with AUD have higher cortisol concentrations and have differences in cytokine expression. Future studies should seek to determine if these differences may explain the higher severity of illness seen in patients with sepsis and AUD.
"enhanced the expression of IκB protein and inhibited the binding activity of NF-κB. These results are in accordance with the fact that NFκB activation in most instances is mediated via rapid degradation of cytoplasmic IκB (Mandrekar et al., 2002). In addition, we show that genistein significantly inhibited DG-induced protein expression of the antioxidant enzyme MnSOD in PC12 cells. "
[Show abstract][Hide abstract] ABSTRACT: We investigated the mechanism of D-galactose (DG)-induced oxidative damage and the neuroprotective action of genistein in PC12 cells.
PC12 cells were treated with 40mM DG dissolved in medium containing 85% RPMI1640, 10% HBS and 5% FBS with or without genistein. We measured the protein expression of β-amyloid (Aβ), advanced glycation end products (AGEs), IκB-α and manganese-superoxide dismutase (MnSOD) by western blotting, intracellular reactive oxygen species (ROS) by 2, 7-dichlorofluorescin-diacetate, and the binding activity of nuclear factor kappa B (NF-κB) by electrophortic mobility shift assay.
DG (40mM) completely retarded cell growth after incubation for 72h, and this effect was not due to osmotic changes, as 40mM mannitol had no effect. Mechanistically, we found that DG increased intracellular ROS starting at 4h and increased Aβ and AGEs at 24h. DG treatment for 24h also increased the binding activity of NF-κB but strongly decreased the expression of IκB-α protein. Furthermore, DG treatment for 48h increased MnSOD protein expression. All these effects of DG were effectively inhibited by genistein (0.5-10μM).
The present study indicates that the protection of genistein against DG-induced oxidative stress in PC12 cells, and the effect is likely mediated by decreased intracellular ROS and binding activity of NF-κB.
Life sciences 11/2010; 88(1-2):82-8. DOI:10.1016/j.lfs.2010.10.021 · 2.70 Impact Factor
"Acute EtOH interferes with the innate immune response: in vivo EtOH administration suppresses cytokine responses induced through Toll-like receptor (TLR)-4 (Kolls et al., 1995; Pruett et al., 2004) and inhibits TLR4 signaling (Yamashina et al., 2000; Mandrekar et al., 2002; Goral et al.. 2004; Goral and Kovacs, 2005). Whereas most studies show that acute EtOH suppresses cytokine responses, the situation is more controversial and more complex in case of chronic EtOH. "
[Show abstract][Hide abstract] ABSTRACT: Both binge and chronic heavy drinking can adversely affect the immune system, but the effects seem to be at least partly dependent on the manner of ethanol (EtOH) consumption. Previous study results from several labs have clearly demonstrated that acute administration of EtOH interferes with innate immune responses. Specifically, EtOH has a general inhibitory effect on cytokine and chemokine production induced by various Toll-like receptor (TLR) ligands, and it suppresses signaling on several levels along the TLR signaling pathways. However, it is not clear whether chronic exposure to ethanol has the same effects or not. The purpose of this study was to investigate the difference between the effect of chronic versus acute EtOH exposure on LPS-induced cytokine production and clustering of components of the TLR4 complex, which is an important early signaling event. Some groups of mice received acute EtOH by oral gavage using our binge drinking model and/or chronic administration of EtOH at 20% (w/v) in the drinking water as the sole liquid source for 4 wk. The cellular distribution of CD14 and TLR4 were studied by confocal microscopy following exposure of peritoneal cells to LPS locally in vivo, and cytokine production in peritoneal fluid and serum was measured by ELISA after LPS injection via a tail vein. Chronic EtOH exposure did not consistently cause significant changes in LPS-induced cytokine production. However, mice previously exposed to chronic EtOH treatment became partially resistant to the suppressive effects of acute EtOH administration with regard to cytokine production. As we have reported previously, acute EtOH treatment suppressed the LPS-induced clustering of TLR4 and CD14 in peritoneal macrophages. However, peritoneal cells from mice treated with chronic EtOH exhibited a greater amount of intracellular expression of CD14 instead of CD14/TLR4 clustering on the membrane following LPS exposure. The results demonstrate different effects of chronic versus acute EtOH treatment on LPS-induced cytokine production in mice. Partial tolerance to the effect of acute EtOH administration caused by chronic EtOH treatment suggests a compensatory mechanism is induced by chronic EtOH administration. Acute EtOH exposure acts probably by disrupting the receptor clustering following LPS recognition, whereas adaptations induced by chronic EtOH treatment seem to involve alteration of LPS receptor expression.
Journal of Immunotoxicology 01/2007; 3(4):217-25. DOI:10.1080/15476910601080156 · 2.05 Impact Factor
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