Mechanisms of alcoholic pancreatitis remain unknown. Previously, we showed that ethanol feeding sensitizes rats to pancreatitis caused by CCK-8, at least in part, by augmenting activation of the proinflammatory transcription factor NF-kappaB. To elucidate the mechanism of sensitization, here we investigate the effect of ethanol on Ca(2+)- and PKC-mediated pathways of CCK-induced NF-kappaB activation using an in vitro system of rat pancreatic acini incubated with ethanol. Ethanol augmented CCK-8-induced activation of NF-kappaB, similar to our in vivo findings with ethanol-fed rats. In contrast, ethanol prevented NF-kappaB activation caused by thapsigargin, an agent that mobilizes intracellular Ca(2+) bypassing the receptor. Pharmacological analysis showed that NF-kappaB activation by thapsigargin but not by CCK-8 is mediated through the calcineurin pathway and that the inhibitory effect of ethanol on the thapsigargin-induced NF-kappaB activation could be through inhibiting this pathway. Ethanol augmented NF-kappaB activation induced by the phorbol ester PMA, a direct activator of PKC. Inhibitory analysis demonstrated that Ca(2+)-independent (novel and/or atypical) PKC isoforms are involved in NF-kappaB activation induced by both CCK-8 and PMA in cells treated and not treated with ethanol. The results indicate that ethanol differentially affects the Ca(2+)/calcineurin- and PKC-mediated pathways of NF-kappaB activation in pancreatic acinar cells. These effects may play a role in the ability of ethanol to sensitize pancreas to the inflammatory response and pancreatitis.
The main finding of this study is the high prevalence of low HDL-C concentrations in the Iranian population, especially in Iranian women, compared with French women. Explanation of this observation could help in establishing prevention strategies.
Acquired immune deficiency syndrome (AIDS) is a clinical disorder caused by the human immunodeficiency virus (HIV) after development of severe immunosuppressive changes. Chronic ethanol (EtOH) consumption accentuates the severity of murine AIDS (MAIDS). Because hormone production is often suppressed by chronic EtOH intake, as well as retrovirus infection, we investigated whether hormone supplementation during chronic EtOH consumption contributes to slowing immune dysfunction caused by LP-BM5 infection and/or EtOH use. Because dehydroepiandrosterone sulfate (DHEAS) was previously shown to have immune-enhancing properties during MAIDS, we determined whether DHEAS reduced cytokine dysregulation otherwise exacerbated by chronic EtOH intake during MAIDS. Adult female C57BL/6 mice were infected with LP-BM5 murine retrovirus. Some were fed 40% EtOH in drinking water and agar gel for 16 weeks postinfection. EtOH consumption further inhibited T- and B-cell proliferation beyond suppression due to retrovirus infection. Interleukin (IL)-2 release produced by concanavalin A-stimulated splenocytes was reduced by EtOH use by infected and uninfected mice. DHEAS overcame much of the effects induced by retrovirus infection and/or EtOH use. IL-4 secretion and IL-6 secretion were enhanced. Hepatic vitamin E levels were decreased by murine retrovirus infection, as well as by EtOH use in both uninfected and infected mice. In addition, DHEAS (0.01%) supplementation during MAIDS prevented the further dysregulation of cytokines and hepatic lipid peroxidation due to EtOH intake, partially restored T- and B-cell proliferation, and maintained hepatic vitamin E levels to near normal levels.
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