ABSTRACT
Excessive alcohol consumption is one of the most significant causes of morbidity and mortality worldwide. Alcohol is oxidized to toxic and carcinogenic acetaldehyde by alcohol dehydrogenase (ADH) and further oxidized to a non-toxic acetate by aldehyde dehydrogenase (ALDH). There are two major ALDH isoforms, cytosolic and mitochondrial, encoded by ALDH1 and ALDH2 genes, respectively. The ALDH2 polymorphism is associated with flushing response to alcohol use. Emerging evidence shows that Lactobacillus and Bifidobacterium species encode alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) mediate alcohol and acetaldehyde metabolism, respectively. A randomized, double-blind, placebo-controlled crossover clinical trial was designed to study the effects of Lactobacillus and Bifidobacterium probiotic mixture in humans and assessed their effects on alcohol and acetaldehyde metabolism. Here, twenty-seven wild types (ALDH2*1/*1) and the same number of heterozygotes (ALDH2*2/*1) were recruited for the study. The enrolled participants were randomly divided into either the probiotic (Duolac ProAP4) or the placebo group. Each group received a probiotic or placebo capsule for 15 days with subsequent crossover. Primary outcomes were measurement of alcohol and acetaldehyde in the blood after the alcohol intake. Blood levels of alcohol and acetaldehyde were significantly downregulated by probiotic supplementation in subjects with ALDH2*2/*1 genotype, but not in those with ALDH2*1/*1 genotype. However, there were no marked improvements in hangover score parameters between test and placebo groups. No clinically significant changes were observed in safety parameters. These results suggest that Duolac ProAP4 has a potential to downregulate the alcohol and acetaldehyde concentrations, and their effects depend on the presence or absence of polymorphism on the ALDH2 gene.
Subject(s)
Acetaldehyde/blood , Alcohol Drinking/blood , Aldehyde Dehydrogenase, Mitochondrial/genetics , Bifidobacterium/metabolism , Ethanol/blood , Lactobacillus/metabolism , Probiotics/administration & dosage , Adult , Alcohol Drinking/genetics , Cross-Over Studies , Double-Blind Method , Humans , Male , Young AdultABSTRACT
Wnt signaling has been implicated in certain inflammatory diseases. However, the biological role in the inflammatory regulation remains to be characterized. We investigated the regulation by Wnt signaling in endothelial cells, which are active participants and regulators of inflammation. Wnt5a induces cyclooxygenase-2 expression and enhances inflammatory cytokines rapidly, whereas Wnt3a shows limited effects, suggesting a role for beta-catenin-independent Wnt signaling in the inflammatory endothelial activation. Pulse-like treatment of Wnt5a induces cyclooxygenase-2 more efficiently than continuous treatment. Wnt5a and TNF-alpha regulate subsets of cytokines overlapping, only partially, with each other. Calcium ionophore enhances endothelial inflammation similarly, whereas calcium chelators and protein kinase C inhibitor block Wnt5a-induced activation, suggesting a role for the Wnt/Ca(2+)/protein kinase C pathway in endothelial inflammatory regulation. Wnt5a activates RelA nuclear translocation and DNA binding. Activated blood vessels, histiocytes, and synoviocytes express Wnt5a in atherosclerosis and rheumatoid arthritis but not in normal tissue, supporting the role of Wnt5a as an inflammatory mediator in vivo. Our data suggest that endothelial inflammation is regulated by a dual system consisting of beta-catenin-independent Wnt signaling and TNF-alpha-mediated signaling.
Subject(s)
Endothelial Cells/drug effects , Proto-Oncogene Proteins/pharmacology , Signal Transduction/drug effects , Wnt Proteins/pharmacology , beta Catenin/metabolism , Animals , Arthritis, Rheumatoid/metabolism , Atherosclerosis/metabolism , Blotting, Western , Calcium/metabolism , Cell Line , Cell Line, Tumor , Cell Movement/drug effects , Cells, Cultured , Cyclooxygenase 2/genetics , Cyclooxygenase 2/metabolism , Cytokines/genetics , Cytokines/metabolism , Endothelial Cells/immunology , Endothelial Cells/metabolism , Gene Expression/drug effects , HeLa Cells , Humans , Immunohistochemistry , Inflammation/genetics , Inflammation/metabolism , NF-kappa B/metabolism , Protein Kinase C/metabolism , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , Recombinant Proteins/pharmacology , Reverse Transcriptase Polymerase Chain Reaction , Tumor Necrosis Factor-alpha/pharmacology , Wnt Proteins/genetics , Wnt Proteins/metabolism , Wnt-5a ProteinABSTRACT
Endothelial inflammation is regulated by a complex molecular mechanism. TC1(C8orf4) is a novel regulator implicated in cancer and inflammation. It is a small protein conserved well among vertebrates. In zebrafish embryos, it is mostly expressed in angio-hematopoietic system and the overexpression induces edema. In human aortic endothelial cells and umbilical vein endothelial cells, TC1 transfection up-regulates key inflammatory cytokines, enzymes, and adhesion proteins including IL-6, IL-1alpha, COX-2, CXCL1, CCL5, CCL2, IL-8, ICAM1, VCAM1, and E-selectin, while TC1 knockdown down-regulates them. TC1 also enhances inflammatory parameters such as monocyte-endothelial adhesion and endothelial monolayer permeability. TC1 is up-regulated by IL-1beta, TNF-alpha, LPS, and phorbol ester, and the up-regulation is inhibited by I-kappaB-kinase inhibitors. TC1, in turn, enhances the nuclear translocation of RelA and the DNA binding activity, suggesting a biological role of amplifying NF-kappaB signaling via a positive feedback. Our findings suggest that TC1 is a novel endothelial inflammatory regulator that might be implicated in inflammatory vascular diseases.
